This Indenturemade the day of between A. B. of, &c., of the one part and C. D. of, &c., of the other partWhereasthe said A. B. is seised (among other hereditaments) of the messuage hereinafter described and hereby conveyed for an estate in fee simple in possession free from incumbrances and has agreed to sell the same to the said C. D. for £100Now this Indenture witnesseththat in pursuance of the said agreement and in consideration of the sum of £100 paid to the said A. B. by the said C. D. (the receipt whereof the said A. B. doth hereby acknowledge) the said A. B. as beneficial owner doth hereby convey unto the said C. D.All thatmessuage or tenement situate &c., and known as, &c.To Holdthe premises unto and to the use of the said C. D. his heirs and assigns [orin fee simple] And the said A. B. doth hereby acknowledge the right of the said C. D. to production and delivery of copies of the following documents of title [mentioning them] and doth undertake for the safe custody thereofIn witness, &c.
This Indenturemade the day of between A. B. of, &c., of the one part and C. D. of, &c., of the other partWhereasthe said A. B. is seised (among other hereditaments) of the messuage hereinafter described and hereby conveyed for an estate in fee simple in possession free from incumbrances and has agreed to sell the same to the said C. D. for £100Now this Indenture witnesseththat in pursuance of the said agreement and in consideration of the sum of £100 paid to the said A. B. by the said C. D. (the receipt whereof the said A. B. doth hereby acknowledge) the said A. B. as beneficial owner doth hereby convey unto the said C. D.All thatmessuage or tenement situate &c., and known as, &c.To Holdthe premises unto and to the use of the said C. D. his heirs and assigns [orin fee simple] And the said A. B. doth hereby acknowledge the right of the said C. D. to production and delivery of copies of the following documents of title [mentioning them] and doth undertake for the safe custody thereofIn witness, &c.
It will be observed that throughout the deed there are no stops, the commencement of the several parts being indicated by capital letters. The draft conveyance having been approved on behalf of the vendor, it is engrossed upon stout paper or parchment, and there remains only the completion of the sale, which usually takes place at the office of the vendor’s solicitor. A purchaser is not entitled to require the vendor to attend personally and execute the conveyance in his presence or that of his solicitor. The practice is for the deed to be previously executed by the vendor and delivered to his solicitor, and for the solicitor to receive the purchase-money on his client’s behalf, since a purchaser is, under the Conveyancing Act 1881, safe in paying the purchase-money to a solicitor producing a deed so executed, when it contains the usual acknowledgment by the vendor of the receipt of the money. Upon the completion, the documents of title are handed over except in the case above referred to, and any claims between the parties in respect of interest upon the purchase-money, apportioned outgoings, or otherwise, aresettled. The conveyance is, of course, delivered to the purchaser, upon whom rests the obligation of affixing the proper stamp—which he may do without penalty within thirty days after execution (Stamp Act 1891). It may be added that, subject to any special bargain, which is rarely made, the costs of the execution by the vendor and other parties whose concurrence is necessary, and of any act required to be done by the vendor to carry out his contract, are borne by the vendor.
Ordinary leases at rack-rents are not generally preceded by a formal agreement, such as is common on a sale of land, or by an investigation into the lessor’s title. As a rule, the principal terms are arranged between the parties, andLeases.embodied with various ancillary provisions in a draft lease, which is prepared by the lessor’s advisers and submitted to the lessee, the ultimate form and contents of the instrument being adjusted by negotiation. If an intending lessee desires to examine the title he must make an express bargain to that effect, for under a contract to grant a lease the intended lessee is not entitled, in the absence of such express stipulation, to call for the title to the freehold (Vendor and Purchaser Act 1874). By the Statute of Frauds all leases, except leases for a term not exceeding three years, and at not less than two-thirds of the rack-rent, were required to be in writing. And now by the Real Property Act 1845, leases required by law to be in writing are voidat lawunless made by deed. An instrument, void as a lease under the act, may, however, be valid as an agreement to take a lease; and since the Judicature Act 1873, under which equitable doctrines prevail in the High Court, a person holding under an agreement for a lease, of which specific performance would be granted, is treated in all branches of that court as if such a lease were already executed. Unless otherwise agreed, a lease is always prepared by a lessor’s solicitor at the expense of the lessee; but the cost of the counterpart (i.e.the duplicate executed by the lessee) is usually borne by the lessor.
Upon the sale and conveyance of a leasehold property substantially the same procedure is observed as above indicated in the case of a freehold. A few additional points, however, may be specially mentioned. Under an openAssignment of leaseholds.contract the vendor cannot be called upon to show the title to the freehold reversion (Vendor and Purchaser Act 1874; Conveyancing Act 1881). Accordingly, the abstract of title begins with the lease, however old; but the subsequent title need not be carried back for more than forty years before the sale. The purchaser, apart from stipulation, must assume, unless the contrary appears, that the lease was duly granted, and upon production of the receipt for the last payment due for rent before completion, that all the covenants and provisions of the lease have been duly performed and observed up to the date of actual completion. The appropriate word of conveyance is “assign,” and a conveyance of leaseholds is generally called an assignment. The vendor’s covenants for title implied by his assigning “as beneficial owner” include, in addition to the covenants implied by those words in a conveyance of freehold, a covenant limited in manner above mentioned, that the lease is valid, and that the rent and the provisions of the lease have been paid and observed up to the time of conveyance (Conveyancing Act 1881). Where the vendor, as is the common case, remains liable after the assignment for the rent and the performance of the covenants, the purchaser must covenant to pay the rent, and perform and observe the covenants and provisions of the lease, and keep the vendor indemnified in those respects.
A mortgage is prepared by the solicitor of the mortgagee, and the mortgagor bears the whole expenses of the transaction. It is seldom that there is any preliminary agreement, because (1) a contract to lend money is not specificallyMortgages.enforceable; and (2) inasmuch as the primary object of a mortgagee is to have his money well secured, he is not, generally, willing to submit to restrictions as to title or evidence of title which might give rise to difficulty or expense in the event of a sale of the mortgaged property. An intending mortgagor is accordingly required to show a title easily marketable, and to verify it at his own cost. A mortgage follows the same general form as a conveyance on sale, the principal points of difference being that the conveyance of the property is preceded by a covenant for the payment of the mortgage money and interest, and followed by a proviso for reconveyance upon such payment, and by any special provisions necessary or proper in the circumstances, such as a covenant for insurance and repairs where the security comprises buildings. The covenants for title implied by a mortgagor conveying “as beneficial owner” are the same as in the case of a vendor, but they are absolute and not qualified in the manner above pointed out.
The beneficial operation of the Conveyancing Act 1881 in shortening conveyances is well illustrated by a modern mortgage. For, by virtue of the act, a mortgagee by deed executed after its commencement has, subject to any contrary provisions contained in the deed, the following powers to the like extent as if they had been conferred in terms: (1) a power of sale exercisable after the mortgage money has become due (a) if notice requiring payment has been served and not complied with for three months, (b) if any interest is in arrear for two months, or (c) there has been a breach of some obligation under the deed or the act other than the covenant for payment of the mortgage money or interest; (2) a power to insure subject to certain restrictions; (3) a power, when entitled to sell, to appoint a receiver; and (4) a power while in possession to cut and sell timber. The act contains ancillary provisions enabling a mortgagee upon a sale to convey the property for such estate or interest as is the subject of the mortgage, and to give a valid receipt for the purchase-money, and the purchaser is amply protected against any irregularities of which he had no notice. There are also large powers of leasing conferred by the act upon mortgagor and mortgagee while respectively in possession, and a power for the mortgagor, whilst entitled to redeem, to inspect and take copies of title-deeds in the mortgagee’s possession. The elaborate provisions for all these purposes which were formerly inserted in mortgage deeds are now omitted; but sometimes the operation of the act is modified in certain respects. The procedure upon a sale by a mortgagee is the same as in the case of any other vendor. He conveys, however, “as mortgagee,” these words implying only a covenant by him against incumbrances arising from his own acts.
The beneficial operation of the Conveyancing Act 1881 in shortening conveyances is well illustrated by a modern mortgage. For, by virtue of the act, a mortgagee by deed executed after its commencement has, subject to any contrary provisions contained in the deed, the following powers to the like extent as if they had been conferred in terms: (1) a power of sale exercisable after the mortgage money has become due (a) if notice requiring payment has been served and not complied with for three months, (b) if any interest is in arrear for two months, or (c) there has been a breach of some obligation under the deed or the act other than the covenant for payment of the mortgage money or interest; (2) a power to insure subject to certain restrictions; (3) a power, when entitled to sell, to appoint a receiver; and (4) a power while in possession to cut and sell timber. The act contains ancillary provisions enabling a mortgagee upon a sale to convey the property for such estate or interest as is the subject of the mortgage, and to give a valid receipt for the purchase-money, and the purchaser is amply protected against any irregularities of which he had no notice. There are also large powers of leasing conferred by the act upon mortgagor and mortgagee while respectively in possession, and a power for the mortgagor, whilst entitled to redeem, to inspect and take copies of title-deeds in the mortgagee’s possession. The elaborate provisions for all these purposes which were formerly inserted in mortgage deeds are now omitted; but sometimes the operation of the act is modified in certain respects. The procedure upon a sale by a mortgagee is the same as in the case of any other vendor. He conveys, however, “as mortgagee,” these words implying only a covenant by him against incumbrances arising from his own acts.
The frame of a strict settlement of real estate, which is usually made either on marriage or by way of resettlement on a tenant in tail under an existing settlement attaining twenty-one, has been much simplified; but such settlements stillSettlements.remain the most technical and most complicated of legal instruments. By virtue of the Settled Land Acts 1882 to 1890, tenants for life and many other limited owners have extensive powers of sale, of leasing, and of doing numerous other acts required in a due course of management. These powers cannot be excluded or fettered by settlors. They are, as a rule, considered in practice to be sufficient, and the corresponding elaborate provisions formerly inserted in settlements are now omitted, the operation of the acts being merely supplemented, where desirable, by some extension of the statutory powers, in relation,e.g., to the investment and application of capital money. To complete the statutory machinery it is desirable that persons should be nominated by the settlement trustees for the purposes of the acts. Since the Conveyancing Act 1881, provisions for the protection of jointresses or persons entitled under settlements to rent charges or annual sums issuing out of the land are no longer required, as all such persons have now powers of distress and entry, and of limiting terms to secure their respective interests. Terms for raising portions must still, however, be expressly created. The Conveyancing Act 1881 also confers large powers of management during the minorities of infants beneficially entitled upon persons either appointed for the purpose by the instrument or being such trustees such as are mentioned in § 42. An estate in tail may now be limited by the use of the words “in tail” without the words “heirs of the body” formerly necessary. And a settlor generally conveys “as settlor,” by which only a covenant for further assurance is implied under the Conveyancing Act 1881. Personal settlements are most often made upon marriage. The settled property is vested in trustees, either by the settlement itself, or in the case of cash, mortgage debts, stocks or shares, by previous delivery or transfer, upon trusts declared by the instrument.
The normal trusts after the marriage are (1) for investment; (2) for payment of the income of the husband’s property to him for life, and of the wife’s property to her for life for her separate use without power of anticipation whilst under coverture; (3) forpayment to the survivor for his or her life of the income of both properties; (4) after the death of the survivor, both as to capital and income, for the issue of the marriage as the husband and wife shall jointly by deed appoint, and in default of joint appointment as the survivor shall by deed or will appoint, and in default of such appointment for the children of the marriage who attain twenty-one, or being daughters marry, in equal shares, with the addition of a clause (called the hotchpot clause) precluding a child who or whose issue takes a part of the fund by appointment from sharing in the unappointed part without bringing the appointed share into account. Then follows a power for the trustees with the consent of the parents whilst respectively living to raise a part (usually a half) of the share of a child and apply it for his or her advancement or benefit. Power to apply income, after the death of the life tenants, for the maintenance and education of infants entitled in expectancy, is conferred upon trustees by the Conveyancing Act 1881. The ultimate trusts in the event of there being no children who attain vested interests are (1) of the husband’s property for him absolutely; and (2) of the wife’s property for such persons as she shall when discovert by deed, or whether covert or discovert by will, appoint, and in default of appointment, for her absolutely if she survive the husband, but if not, then for her next of kin under the Statute of Distributions, excluding the husband. For all ordinary purposes the trustees have now under various statutes sufficient powers and indemnities. They may, however, in some cases need special protection against liability. A power of appointing new trustees is supplied by the Trustee Act 1893. It is usually made exercisable by the husband and wife during their joint lives, and by the survivor during his or her life.
The normal trusts after the marriage are (1) for investment; (2) for payment of the income of the husband’s property to him for life, and of the wife’s property to her for life for her separate use without power of anticipation whilst under coverture; (3) forpayment to the survivor for his or her life of the income of both properties; (4) after the death of the survivor, both as to capital and income, for the issue of the marriage as the husband and wife shall jointly by deed appoint, and in default of joint appointment as the survivor shall by deed or will appoint, and in default of such appointment for the children of the marriage who attain twenty-one, or being daughters marry, in equal shares, with the addition of a clause (called the hotchpot clause) precluding a child who or whose issue takes a part of the fund by appointment from sharing in the unappointed part without bringing the appointed share into account. Then follows a power for the trustees with the consent of the parents whilst respectively living to raise a part (usually a half) of the share of a child and apply it for his or her advancement or benefit. Power to apply income, after the death of the life tenants, for the maintenance and education of infants entitled in expectancy, is conferred upon trustees by the Conveyancing Act 1881. The ultimate trusts in the event of there being no children who attain vested interests are (1) of the husband’s property for him absolutely; and (2) of the wife’s property for such persons as she shall when discovert by deed, or whether covert or discovert by will, appoint, and in default of appointment, for her absolutely if she survive the husband, but if not, then for her next of kin under the Statute of Distributions, excluding the husband. For all ordinary purposes the trustees have now under various statutes sufficient powers and indemnities. They may, however, in some cases need special protection against liability. A power of appointing new trustees is supplied by the Trustee Act 1893. It is usually made exercisable by the husband and wife during their joint lives, and by the survivor during his or her life.
The form and contents of wills are extremely diverse. A will of, perhaps, the commonest type (a) appoints executors and trustees; (b) makes a specific disposition of a freehold or leasehold residence; (c) gives a few legacies orWills.annuities; and (d) devises and bequeaths to the executors and trustees the residue of the real and personal estate upon trust to sell and convert, to invest the proceeds (after payment of debts and funeral and testamentary expenses) in a specified manner, to pay the income of the investments to the testator’s widow for life or until another marriage, and subject to her interest, to hold the capital and income in trust for his children who attain twenty-one, or being daughters marry, in equal shares, with a power of advancement. Daughters’ shares are frequently settled by testators upon them and their issue on the same lines and with the same statutory incidents as above mentioned in the observations upon settlements; and sometimes a will contains in like manner a strict settlement of real estate. It is a point often overlooked by testators desirous of benefiting remote descendants that future interests in property must, under what is known as the rule against perpetuities, be restricted within a life or lives in being and twenty-one years afterwards. In disposing of real estate “devise” is the appropriate word of conveyance, and of personal estate “bequeath.” But neither word is at all necessary. “I leave all I have to A. B. and appoint him my executor” would make an effectual will for a testator who wished to give all his property, whether real or personal, after payment of his debts, to a single person. By virtue of the Land Transfer Act 1897, Part I., real estate of an owner dying after 1897 now vests for administrative purposes in his executors or administrators, notwithstanding any testamentary disposition.
It remains to mention that by the Land Transfer Act 1897 a system of compulsory registration of title, limited to the county of London, was established. (SeeLand Registration.)
Conveyancing counsel to the court(i.e.to the chancery division of the High Court) are certain counsel, in actual practice as conveyancers, of not less than ten years’ standing, who are appointed by the lord chancellor, to the number of six, under s. 40 of the Master in Chancery Abolition Act 1852. They are appointed for the purpose of assisting the court in the investigation of the title to any estate, and upon their opinion the court or any judge thereof may act. Any party who objects to the opinion given by any conveyancing counsel may have the point in dispute disposed of by the judge at chambers or in court. Business to be referred to conveyancing counsel is distributed among them in rotation, and their fees are regulated by the taxing officers.
Conveyancing counsel to the court(i.e.to the chancery division of the High Court) are certain counsel, in actual practice as conveyancers, of not less than ten years’ standing, who are appointed by the lord chancellor, to the number of six, under s. 40 of the Master in Chancery Abolition Act 1852. They are appointed for the purpose of assisting the court in the investigation of the title to any estate, and upon their opinion the court or any judge thereof may act. Any party who objects to the opinion given by any conveyancing counsel may have the point in dispute disposed of by the judge at chambers or in court. Business to be referred to conveyancing counsel is distributed among them in rotation, and their fees are regulated by the taxing officers.
United States.—American legislation favours the general policy of registering all documents in the contents of which the public have an interest, and its tendency has been steadily towards more and more full registration both of documents and statistics. From the early days of the colonial era it has been customary to record wills and conveyances of real estate in full in public books, suitably indexed, to which free access was given. During the last decade of the 19th century, three states—Illinois, Massachusetts, and Ohio—adopted the main features of the Torrens or Prussian system for registering title to land rather than conveyances under which title may be claimed. These are the ascertainment by public officers of the state of the title to some or all of the parcels of real estate which are the subject of individual property within the state; the description of each parcel (giving its proper boundaries and characteristics) on a separate page of a public register, and of the manner in which the title is vested; the issue of a certificate to the owner that he is the owner; the official notation on this register of each change of title thereafter; and a warranty by the government of the title to which it may have certified. To make the system complete it is further requisite that every landowner should be compelled to make use of it, and that it should be impossible to transfer a title effectually without the issue of such a government certificate in favour of the purchaser.
Constitutional provisions have been found to prevent or embarrass legislation in these directions in some of the states, but it is believed that they are nowhere such as cannot be obeyed without any serious encroachment on the principles of the new system (Peoplev.Chase, 165 Illinois Reports, 527;Statev.Guilbert, 56 Ohio State Reports, 575;Peoplev.Simon, 176 Illinois Reports, 165;Tylerv.Judges, 173 Massachusetts Reports; 55 North-Eastern Reporter, 812;Hamiltonv.Brown, 161 United States Reports, 256).
Conveyances which have been duly recorded become of comparatively little importance in the United States. The party claiming immediately under them, if forced to sue to vindicate his title, must produce them or account for their loss; but any one deriving title from him can procure a certified copy of the original conveyance from the recording officer and rely on that. Equitable mortgages by a deposit of title-deeds are unknown.
The general prevalence of public registry systems has had an influence in the development of American jurisprudence in the direction of supporting provisions in wills and conveyances, which, unless generally known, might tend to mislead and deceive, such as spendthrift trusts (Nicholsv.Eaton, 91 United States Reports, 716).
Conveyances of real estate are simple in form, and are often prepared by those who have had no professional training for the purpose. Printed blanks, sold at the law-stationers, are commonly employed. The lawyers in each state have devised forms for such blanks, sometimes peculiar in some points to the particular state, and sometimes copied verbatim from those in use elsewhere. Deeds intended to convey an absolute estate are generally either of the form known aswarranty deedor of that known asrelease deed. The release deed is often used as a primary conveyance without warranty to one who has no prior interest in the land. Uniformity in deeds is rendered particularly desirable from the general prevalence of the system of recording all conveyances at length in a public office. Record books are printed for this purpose, containing printed pages corresponding to the printed blanks in use in the particular state, and the recording officer simply has to fill up each page as the deed of similar form was filled up. One set of books may thus be kept for recording warranty deeds, another for recording release deeds, another for recording mortgage deeds, another for leases, &c.
Authorities.—Davidson,Precedents and Forms in Conveyancing(London, 1877 and 1885); Key and Elphinstone,Compendium of Precedents in Conveyancing(London, 1904); Elphinstone,Introduction to Conveyancing(London, 1900); Prideaux,Precedents in Conveyancing(1904); Pollock,The Land Laws(London, 1896).
Authorities.—Davidson,Precedents and Forms in Conveyancing(London, 1877 and 1885); Key and Elphinstone,Compendium of Precedents in Conveyancing(London, 1904); Elphinstone,Introduction to Conveyancing(London, 1900); Prideaux,Precedents in Conveyancing(1904); Pollock,The Land Laws(London, 1896).
(S. Wa.; S. E. B.)
CONVEYORS.“Conveyor” (for derivation seeConveyance) is a term generally applied to mechanical devices designed for the purpose of moving material in a horizontal or slightly inclined direction; in this article, however, are included a variety of appliances for moving materials in horizontal, vertical and combined horizontal and vertical directions. The material so handled may be conveyed in a practically uninterrupted stream,as in the case of worms, bands and pushplate conveyors, or elevators carrying grain or coal, &c.; or it may be conveyed from one point to another, intermittently, that is to say in a succession of separate loads, as happens with single bucket elevators, furnace hoists, rope and chain haulage, and also in the case of ropeways and aerial cableways. Some of these devices are of great antiquity, others are of quite modern origin. The principles of their construction are simple and easy of understanding, but by variations in the details of their construction the engineer has adapted these few appliances to the most varied work. At one end of the scale they may be used for such light duties as conveying the goods purchased by a customer to the packers and bringing them back made up into a parcel or for taking his money to the cashier and returning the change. At the other they are adopted for handling large quantities of heavy material at a minimum expenditure of human labour. Coal, for instance, a more or less friable substance, the value of which is seriously diminished by fracture, may be mechanically handled with a minimum risk of breakage. The difficult problem of handling the contents of gas retorts and coke ovens, and of simultaneously quenching and conveying the glowing material, has been solved. Perhaps an even more astonishing piece of work is the manipulation of the iron from the blast furnace; for instance, liquid metal is drawn from a furnace into pouring pots which in their turn discharge it to and distribute it over a pig-iron casting machine, which is practically a conveyor for liquid metal, consisting of a strand of moving moulds from which the solidified pigs, after cooling in water, are automatically removed after reaching the loading terminal over the railway trucks. Certain types of conveyors may be made to combine efficiently, with their primary work of transport, complex sorting, sifting, drying and weighing operations.
Worm Conveyors.—The worm conveyor, also known as the Archimedean screw, is doubtless the most ancient form of conveyor. It consists of a continuous or broken blade screw set on a spindle. This spindle is made to revolve in a suitable trough, and as it revolves any material put in is propelled by the screw from one end of the trough to the other. Such conveyors have been used in flour-mills for centuries. The writer has seen in an East Anglian mill which was over 250 years old disused screw conveyors, probably as old as the mill, consisting of spindles of octagonal shape, made of not too hard wood, around which a broken blade screw was formed by the insertion at regular intervals of small blades of hard wood (fig. 1). Modern worm conveyors usually consist of a spindle formed of a length of wrought iron piping, to which is fitted either a broken or continuous worm. In the former case (fig. 2) the worm is composed of a series of blades or paddles arranged like a spiral round the spindle; each blade is fixed, by means of its shank, in a transverse hole in the spindle, and the shank is held in position by being tapped and fitted with a nut. In this way is formed, out of separate blades, a practically complete screw, technically known as a “paddle worm.” The lengths or sections of the worm run to about 8 ft., the various lengths being coupled by turned gudgeons, which also serve as journals for the bearings. In the so-called continuous worm conveyors the screw is formed of a continuous sheet-iron spiral (fig. 3). Sometimes a narrow groove is cut in spiral form on the spindle, and in this groove the sheet-iron spiral is secured.
Thespiraloranti-frictionconveyor (fig. 4) was introduced about 1887. In this case a narrow spiral, which passes concentrically round the spindle, with a space between both, is fixed to it at set intervals by small blades, each of which is itself fixed by its shank and a nut to the spindle. The spiral may be made of almost any section, from a round bar about ½ in. in diameter to L or T section, but is preferably a flat bar. Worms are fitted into wooden or iron troughs leaving a clearance of1⁄8to1⁄4in. The spindle must be supported at suitable intervals by bearings, preferably of the bush type. A continuous worm, being more rigid than a paddle worm, needs fewer supports. The lid of the worm trough should be loose, not screwed on, because in case of an accumulation of feed through a choke in a delivery spout the paddles of a paddle worm would be broken, or a continuous worm stripped, unless the material could throw off the lid and relieve the worm. The ratios of the pitch of the worm to the diameter must be regulated by the nature of the material to be conveyed, and will vary from one-third to a pitch equal to, or even exceeding, the diameter. The greater the pitch the larger the capacity, but also the greater the driving power required, at the same speed. For handling materials of greater specific gravity, such as cement, &c., it is advisable to use a smaller pitch than for substances of lower specific gravity, such as grain. The capacity of a continuous worm exceeds that of either a paddle or spiral conveyor of the same diameter, pitch and speed. As regards the relative efficiency of paddle and spiral conveyors a series of careful tests made by the writer indicated that, run at a slow speed the paddle worm, but at a high speed the spiral worm, has the greater efficiency. There is of course a speed at which the efficiency of both types is about equal, and that is at 150 revolutions per minute for conveyors 4 to 6 in. in diameter.
The power necessary to drive worm conveyors under normal conditions is very considerable; a continuous worm of 18 to 20 in. diameter running at 60 revolutions per minute will convey 50 tons of grain per hour over a distance of a hundred feet at an expenditure of 18½ to 19 H.P. A material like cement would require rather more power because of the greater friction of the cement against the blades and the trough. Delivery from a worm conveyor can be effected at any desired point, all that is necessary being to cut an outlet, which should preferably be as wide as the diameter of the worm, because the worm delivers only on its leading side, and is practically empty on the other side, so that a smaller outlet might only give exit to a portion of the feed, unless it was on the leading side.
A special form of worm conveyor is thetubular(fig. 5), which consists of an iron tube with a continuous spiral fitted to its innerperiphery, or of iron or wooden tubes of square sections fitted with fixed baffle plates inside. In working it revolves bodily on suitable rollers. This type is more costly than the ordinary worm conveyors, and also requires more power. Its efficiency is, moreover, easily impaired if run at too high a speed, because the centrifugal force asserts itself and counteracts the propulsion, which in this case is effected by gravity. Some experiments made in 1868 by George Fosbery Lyster, engineer of the Liverpool docks, gave convincing results (seeProc. Inst. Mech. Eng., August 1869). The tubular worm conveyor is suitable where a granular material has to be moved over a comparatively short distance, say from one building to another on the same level, and where no bridge is available for the installation of any other kind of conveyor. Conveyors of this type have, however, come into use for conveying hard and cutting substances over considerable lengths. Ordinary worm conveyors are practically debarred from use for such substances on account of the short life of the intermediate bearings, which are not necessary with externally supported tubular worms.
To sum up, worm conveyors are of the simplest construction and of small prime cost. The terminals again are much less expensive than those of most other kinds of conveyors. When the distance to be traversed by the material is short, the worm conveyor has this advantage, that it is cheaper than other kinds of conveyors. If it be desired not only to convey but also to mix two or more materials, such as cement and sand in a dry state, or poultry food, this appliance is thoroughly well adapted for the work. On the other hand, there is a grinding action exercised on any material conveyed, and when hard or cutting substances are handled the wear and tear on the conveyor blades, trough and bearings is very great, and the power absorbed by a worm conveyor is a sensible item.
Band Conveyors.—The inventor of band conveyors for the handling of grain and minerals was G. F. Lyster, who, as already mentioned, in 1868 carried out exhaustive experiments at the Liverpool docks, where he established the band conveyor as a grain-handler. For granaries the band conveyor is an ideal appliance. Its capacity is great, and it can be run at relatively high speeds with a moderate expenditure of power. The band conveyor of to-day is an endless belt of canvas or more often india-rubber with insertion, and when fitted with the usual receiving and delivery appliances can be used to handle grain from or into granaries and also to feed bins or sections of a warehouse. The endless bands run over terminal pulleys, and are also supported on their way by a series of guide rollers, which are in greater number on the loaded than on the empty strand. The band is usually run quite flat, except that at the point or points where the grain is fed on it is slightly hollowed for a few feet, by means of two curving rolls which are set obliquely so as to make it trough-shaped. The supporting or guide rollers are 4 in. to 6 in. in diameter, and are sometimes made of wood, but more often consist of steel tubes to which spindles with conical end gudgeons are secured. The gudgeons generally run in suitable bush-bearings, which should be well lubricated. Band conveyors should be driven on the delivery and not the receiving terminal, as the tight side of the band is the flattest. The guide rollers, for ordinary grain conveyors, are fitted to the upper or working side of the band at intervals of about 6 ft., and at distances of 12 ft. on the lower or return strand. In cases where both strands of the band are used for carrying grain, the lower strand must be supported by as many rollers as the upper. Under such conditions, terminal pulleys must be of larger diameter than usual, the object being to throw the two strands farther apart, so as to give sufficient space between the two strands to spout the feed in and out again at the other end. The two strands can be run any distance apart by the use of two additional pulleys for the terminals. This arrangement would be in place where it was desired, as it might be, to run one strand of the band along the top floor of the granary to distribute, while the other strand travelled along the ground-floor or basement to withdraw, the grain.
Band conveyors are kept tight, when the band is not very long, by a tightening gear, similar to that used on elevators, and consisting of two screws which push or better pull the two pedestals of one terminal pulley farther away from the other terminal. If the band is of such length that an adjustment of 4 to 5 ft. on the tightening gear is not sufficient, it is advisable to use in place of screws a tightening pulley, over which the belt passes, but which is itself held in tension by weights. The choice of the exact tightening gear will depend on various considerations, the length of the belt, the type of throw-off carriage used, and the quality of the belt all being factors to be considered. The throw-off carriage (fig. 6), which serves to withdraw material from the band at any desired point, is a simple but ingenious appliance consisting essentially of guide pulleys which by raising one part of the band and lowering the other have the effect of causing the grain to quit the surface of the band at the point where it is deflected upwards. The grain is thus cast clear of the band, and into the air, being caught as it falls in a hopper and spouted in any desired direction. Throw-off carriages differ in certain details, but the principle is the same. For feeding a band conveyor it is important to give the material a horizontal velocity, approaching that of the band. The grain should therefore be fed through a spout rather less in breadth than half of the width of the band, and set at an incline of 42½° to the horizontal. Band conveyors run at a speed of 400 to 600 ft. per minute, according to the nature of the material; oats, for instance, would be liable to be blown off the band at a speed in excess of 500, which would be suitable for wheat. Nuts, maize and the heavier seeds could be carried at 600. The power consumption by a grain-laden band compares favourably with any other form of conveyor. An 18-in. band 100 ft. in length running 500 ft. per minute would carry 50 tons per hour at an expenditure of only 4.5 H.P.
Band conveyors are kept tight, when the band is not very long, by a tightening gear, similar to that used on elevators, and consisting of two screws which push or better pull the two pedestals of one terminal pulley farther away from the other terminal. If the band is of such length that an adjustment of 4 to 5 ft. on the tightening gear is not sufficient, it is advisable to use in place of screws a tightening pulley, over which the belt passes, but which is itself held in tension by weights. The choice of the exact tightening gear will depend on various considerations, the length of the belt, the type of throw-off carriage used, and the quality of the belt all being factors to be considered. The throw-off carriage (fig. 6), which serves to withdraw material from the band at any desired point, is a simple but ingenious appliance consisting essentially of guide pulleys which by raising one part of the band and lowering the other have the effect of causing the grain to quit the surface of the band at the point where it is deflected upwards. The grain is thus cast clear of the band, and into the air, being caught as it falls in a hopper and spouted in any desired direction. Throw-off carriages differ in certain details, but the principle is the same. For feeding a band conveyor it is important to give the material a horizontal velocity, approaching that of the band. The grain should therefore be fed through a spout rather less in breadth than half of the width of the band, and set at an incline of 42½° to the horizontal. Band conveyors run at a speed of 400 to 600 ft. per minute, according to the nature of the material; oats, for instance, would be liable to be blown off the band at a speed in excess of 500, which would be suitable for wheat. Nuts, maize and the heavier seeds could be carried at 600. The power consumption by a grain-laden band compares favourably with any other form of conveyor. An 18-in. band 100 ft. in length running 500 ft. per minute would carry 50 tons per hour at an expenditure of only 4.5 H.P.
While the band conveyor is an ideal conveyor in warehouses and mills, it is also capable of rendering good service in handling such heavy materials as coal and minerals. Of course for such purposes the band and its fittings must be of much more substantial construction. The central portions of the band carrying the load, being subjected to great wear and tear, are often madeof solid india-rubber extending to nearly half the thickness of the band in the middle, and tapering off towards the edges, while the surface facing the guide rollers is of insertion coated with india-rubber. Bands properly prepared and stretched will bear a strain of 3 tons to the square inch. Balata bands may be used in place of india-rubber, but though less expensive are not so lasting. Bands that have to carry coal or minerals are usually curved along the entire length of the upper or loaded strand into a trough shape by guide rollers (fig. 7). Bands of woven wire are sometimes used with coal-washing plants, but have the disadvantage of lack of durability. They are more liable to stretch and are high in price. They may be run as high as about 600 ft. per minute, but to ensure proper grip-driving terminals must either be faced with leather or made of wood.
The speed of band conveyors loaded with coal or minerals greatly depends on the size of the fragments; the proper speed for large pieces would be 150-200 ft. per minute, while smaller material could be carried at a maximum velocity of 700-750 ft. Band conveyors will carry in an upward direction, up to 24 degrees, without any loss of capacity. They can be used not only to carry light and heavy bodies, such as grain and coal, in a continuous stream, but also to convey relatively large bodies such as sacks of flour, or cement, &c., intermittently. Thus a band 26 in. wide and 350 ft. long is used at a flour-mill in York to load sacks of flour into railway trucks; by this means 12 wagons can be loaded by two men in 1 hour. Band conveyors are not necessarily fixed in one place. A portable model has rendered good service in tunnel-cutting, mining and quarrying. This band is mounted in a light steel frame, itself fitted with small wheels, so as to be readily put in any required position, and is entirely self-contained, being provided with tightening gear, a small motor, &c. If required, several lengths can be joined together, or one band can deliver upon another at a lower level. The same advantages that attend the use of the band-conveyor for handling grain may be claimed for this appliance when carrying coal and heavy bodies, namely the demand for relatively small power, smooth and noiseless work, and gentle handling of material. On the other hand the feed cannot be withdrawn at intermediate points except by means of a throw-off carriage. The numerous bearings of the guide rollers require careful lubrication, and the rubber bands should be protected as much as possible from changes of temperature.
Themetal bandor belt conveyor, a modification of the rubber or canvas band conveyors, is an endless belt composed of iron plates connected to endless chains, usually of malleable cast iron, running under the plates. Such appliances, being obviously more cumbrous than band conveyors, are only used in handling material of a hard and cutting nature. They usually deliver only at the end, but if intermediate delivery be desired a scraper may be so fixed across the band at a given point, at an angle of 45°, as to scrape the whole or part of the feed into a shoot, or a scraper may be mounted obliquely on a suitable carriage which can be moved to any points at which delivery may be required. In some bands of this type supporting rollers are attached to the links and travel with them, or are fixed to the framing so that the band runs over them, an arrangement which has the advantage of economizing driving power and of promoting smooth running. Metal band conveyors are tightened in the same way as textile or rubber bands, and may run at a speed of 60 to 120 ft. per minute. The driving gear must always be placed at the delivery terminal, so that the loaded strand is in tension. Such appliances are often used as sorting tables or picking bands, for instance, for coal, cement, minerals, &c.
In another modification of the metal band conveyor, thetravelling troughconveyor, the sides of each plate are turned up so as to form the conveying surface of the band into a continuous trough. With this arrangement intermediate delivery is impossible, as the sides of the trough will not allow the use of a scraper. As compared with push-plate conveyors (which consist of scrapers mounted on endless travelling chains that run usually in troughs), travelling trough conveyors are gentle handlers of material.
A conveyor which is capable of dealing with many different kinds of material is known as thevibrating troughconveyor. It is so far like the band and travelling trough conveyor that the material it conveys from one point to another is conveyed without the use of any stirring or pushing agent, such as belong to worm, push-plate and cable trough conveyors. For materials requiring gentle treatment, this type of conveyor is eminently suitable. There are different kinds of vibrating trough conveyors. In one type the trough is caused to make a reciprocating motion by means of a crank and connecting rod, the trough itself being supported on rollers. In another type the trough is actuated by a cam, or by cranks with some kind of quick return motion. In the appliance known as the Zimmer or swinging conveyor the trough is supported in its reciprocating motion by means of laminated spring legs set obliquely to the trough. These legs are securely bolted at one end to the floor or any other solid support, and at the other end to the trough itself; hence no lubrication is required, as would be the case with supporting rollers. Moreover the combined action of the reciprocating motion of the crank and the rocking of the spring legs has the effect of causing the material to travel faster in the trough with a given stroke of the crank than would be the case with any other support. The material to be conveyed is not carried along with its support as in the case of a band or travelling trough conveyor, but is caused to move in a series of hops, to use popular language.
The action will be sufficiently explained by the appended diagram (fig. 8), which, however, is exaggerated to give a clearer idea of the actual movements, which are on quite a small scale. The line AB represents the bottom of the trough, while CC are two of the spring legs; the full lines indicate the spring legs at the extreme backward position of the crank, while the dotted lines show the spring legs and bottom of the trough at the extreme forward position of the crank D. The material to be conveyed, represented by E, is thrown forward by the forward movement of the crank, and describes a short parabolic curve; it is thrown at about a right angle to the inclined legs CC, but before it has time to complete its parabolic course, the trough has been moved by the crank into its original position. As soon as the material has dropped down, the trough makes another forward movement, whereupon the material is thrown forward another stage, and this process, which is continually repeated, as indicated by the letters E1, E2, E3, has the effect of carrying or conveying the material in the direction desired. It is important to note that the actual movement both of trough and material is within narrow bounds; the horizontal movement of the trough is only about 1 in., while the vertical or upward movement is about1⁄8in. The material is conveyed by this vibrating trough with a minimum of friction, as it is evident that the material is carried forward without any contact with the trough, while the very nature of the motion precludes injurious friction between the particles themselves. When the trough is full the material will move as it were in a solid mass.An important improvement in this type of vibrating trough conveyor is the balanced conveyor, in which the trough is made in two sections, one being placed at a slightly lower level than the other, so that one-half may deliver into the other half. The two sections are driven by triple or quadruple cranks set at an angle of about 180° to one another. In this case one-half of the conveyor will move forward while the other moves backward, thus balancing each other (fig. 9). At the same time the material keeps moving in the same direction because all the spring legs are of the same inclination. It is usual to drive balanced conveyors at or near the centre of their length, but they may also be driven from one end,in which case the balancing of the conveyor would be effected by a powerful volute spring which is compressed and released by a crank and connecting rod, in place of being connected to one-half of the conveyor. Two sections of a Zimmer conveyor can be made to run in opposite directions by merely reversing the inclination of the spring legs; in such a case the sections of a trough would be connected by a flexible coupling. Conveyors of this type have been used in lengths up to 500 ft., and in widths of over 6 ft. The feed can be received or discharged at any desired point in the length; for drawing off material at intermediate points it is only necessary to open a slide in the bottom of the trough. If a great increase be desired in the capacity of this conveyor the connecting rod may be attached, not to the trough at all, but to the spring legs at a point of about a third or half-way from the base, so that the free ends of the legs can swing the trough backward and forward; by this means the stroke is amplified and consequently the capacity is increased, while the driving power required is practically the same.Fig. 9.The power absorbed by the Zimmer conveyor is comparatively small; a length of 100 ft. conveying a load of 50 tons per hour takes 8.75 h.p. With a speed of 300-370 revolutions per minute of the conveyor, the material will traverse 40-70 ft. per minute. The gentle action of this appliance has caused it to be largely used in dealing with friable materials, such as coal. The simplicity of the mechanism leaves little to get out of order, and the entire absence of travelling gear, such as supporting rollers, is a valuable feature. The capacity of the conveyor may be sensibly increased by running it on a downward gradient, while the capacity will be correspondingly diminished by working in an upward direction. Among many purposes for which this type of conveyor has been found suitable is that of a drainer in connexion with coal-washing plants. A perforated plate at the head will allow the water to escape, while the coal is carried to the other end. A slight upward slant permits the water left with the coal to run back and escape. In colliery work this conveyor makes a suitable picking table. The motion of the trough, while not so fast as to baffle the pickers, has the advantage of uniformly spreading the lumps of coal. This apparatus also lends itself to the grading of coal. All that is necessary is to fit the trough with a sieve which divides it into an upper and lower deck. The coarser material passes along the top of the sieve, while the finer coal, sifted out by the perforations, travels along the bottom of the trough till discharged. In spite of the gentle propelling action of this conveyor, it has a thorough sifting action; a perforated plate from 10 to 12 ft. long is usually sufficient to separate any desired grade, and at a certain Belgian colliery a conveyor of this type fitted with grading sieves feeds seven trucks standing in a row, but each on a different siding, and each taking coal of a different size. This conveyor has been found useful both as a drying and cooling appliance. Several substances of a sticky nature, such as moist sugar, which are difficult to deal with mechanically, can be efficiently handled by the swinging conveyor.
The action will be sufficiently explained by the appended diagram (fig. 8), which, however, is exaggerated to give a clearer idea of the actual movements, which are on quite a small scale. The line AB represents the bottom of the trough, while CC are two of the spring legs; the full lines indicate the spring legs at the extreme backward position of the crank, while the dotted lines show the spring legs and bottom of the trough at the extreme forward position of the crank D. The material to be conveyed, represented by E, is thrown forward by the forward movement of the crank, and describes a short parabolic curve; it is thrown at about a right angle to the inclined legs CC, but before it has time to complete its parabolic course, the trough has been moved by the crank into its original position. As soon as the material has dropped down, the trough makes another forward movement, whereupon the material is thrown forward another stage, and this process, which is continually repeated, as indicated by the letters E1, E2, E3, has the effect of carrying or conveying the material in the direction desired. It is important to note that the actual movement both of trough and material is within narrow bounds; the horizontal movement of the trough is only about 1 in., while the vertical or upward movement is about1⁄8in. The material is conveyed by this vibrating trough with a minimum of friction, as it is evident that the material is carried forward without any contact with the trough, while the very nature of the motion precludes injurious friction between the particles themselves. When the trough is full the material will move as it were in a solid mass.
An important improvement in this type of vibrating trough conveyor is the balanced conveyor, in which the trough is made in two sections, one being placed at a slightly lower level than the other, so that one-half may deliver into the other half. The two sections are driven by triple or quadruple cranks set at an angle of about 180° to one another. In this case one-half of the conveyor will move forward while the other moves backward, thus balancing each other (fig. 9). At the same time the material keeps moving in the same direction because all the spring legs are of the same inclination. It is usual to drive balanced conveyors at or near the centre of their length, but they may also be driven from one end,in which case the balancing of the conveyor would be effected by a powerful volute spring which is compressed and released by a crank and connecting rod, in place of being connected to one-half of the conveyor. Two sections of a Zimmer conveyor can be made to run in opposite directions by merely reversing the inclination of the spring legs; in such a case the sections of a trough would be connected by a flexible coupling. Conveyors of this type have been used in lengths up to 500 ft., and in widths of over 6 ft. The feed can be received or discharged at any desired point in the length; for drawing off material at intermediate points it is only necessary to open a slide in the bottom of the trough. If a great increase be desired in the capacity of this conveyor the connecting rod may be attached, not to the trough at all, but to the spring legs at a point of about a third or half-way from the base, so that the free ends of the legs can swing the trough backward and forward; by this means the stroke is amplified and consequently the capacity is increased, while the driving power required is practically the same.
The power absorbed by the Zimmer conveyor is comparatively small; a length of 100 ft. conveying a load of 50 tons per hour takes 8.75 h.p. With a speed of 300-370 revolutions per minute of the conveyor, the material will traverse 40-70 ft. per minute. The gentle action of this appliance has caused it to be largely used in dealing with friable materials, such as coal. The simplicity of the mechanism leaves little to get out of order, and the entire absence of travelling gear, such as supporting rollers, is a valuable feature. The capacity of the conveyor may be sensibly increased by running it on a downward gradient, while the capacity will be correspondingly diminished by working in an upward direction. Among many purposes for which this type of conveyor has been found suitable is that of a drainer in connexion with coal-washing plants. A perforated plate at the head will allow the water to escape, while the coal is carried to the other end. A slight upward slant permits the water left with the coal to run back and escape. In colliery work this conveyor makes a suitable picking table. The motion of the trough, while not so fast as to baffle the pickers, has the advantage of uniformly spreading the lumps of coal. This apparatus also lends itself to the grading of coal. All that is necessary is to fit the trough with a sieve which divides it into an upper and lower deck. The coarser material passes along the top of the sieve, while the finer coal, sifted out by the perforations, travels along the bottom of the trough till discharged. In spite of the gentle propelling action of this conveyor, it has a thorough sifting action; a perforated plate from 10 to 12 ft. long is usually sufficient to separate any desired grade, and at a certain Belgian colliery a conveyor of this type fitted with grading sieves feeds seven trucks standing in a row, but each on a different siding, and each taking coal of a different size. This conveyor has been found useful both as a drying and cooling appliance. Several substances of a sticky nature, such as moist sugar, which are difficult to deal with mechanically, can be efficiently handled by the swinging conveyor.
Thegravityortilting bucketconveyor can be used as a combined elevator and conveyor. It consists essentially of two endless chains or ropes held at fixed distances apart by suitable bars which are fitted with small rollers at each end. Every link, or second link, carries a bucket, and the whole forms an endless chain of buckets. But these buckets, unlike elevator buckets, which are bolted on to a band or chain, are free to move on the axis on which they are suspended above their centre of gravity. When the conveyor is at work the buckets will always be in an upright position, whether the motion be vertical or horizontal. Each bucket carries its load to the point at which delivery is required, where an adjustable tippling device is ready to catch and tilt the bucket, thus emptying it. This type of conveyor is chiefly used in connexion with coal stores and boiler houses, where it has undeniable advantages. For instance, in feeding overhead bunkers a well-designed gravity bucket conveyor may do the work of (1) a horizontal conveyor in bringing coal from the railway siding, (2) a vertical elevator in raising it to the bunkers, and (3) a horizontal conveyor in distributing it to the respective bunkers. In some cases the returning empty strand of buckets is used to clear the ashes from under the boilers.
Conveyors of this type run at a mean rate of 40 ft. per minute, and if it be desired to attain a given capacity the size of the buckets must be adapted to the increased load as an increase of speed for a higher capacity is impracticable. The power absorbed is not great, the heaviest demand on the motive force being made by the elevating operation. Such conveyors have the merit of handling the material gently, while feeding and discharging can take place at any point. There are many journals to be looked after, but in the most approved systems their lubrication is effected automatically. Whilst such a plant has the advantage of requiring only one driving gear, a breakdown at one point of the installation means the stoppage of the whole.