US2757756A - Hoists - Google Patents

Description

Aug. 7, 1956 R. F. WARRY 2,757,755

HoIsTs Filed NOV. l2. 1952 Sheets-Sheet, l

. REGlNALp FRANK wARRy 7 BY Z0. E

AGENTS Aug 7, 195e R. F. WARRY M5755@ HOISTS Filed Nov. l2, 1952 5 Sheets-Sheet 2 /NVNToR l Rial-NA@ FRANK WARRy l AGENTS Aug. 7, 1956 R. F. WARRY 2,757,755

HOISTS Filed NOV. l2, 1952 b' SheetsSheet 5 /NVENTDR REemA-Lp FRAM wARRy AGENTS Aug. 7, 1956 R. F. WARRY HOISTS Sheets-Sheet 4 Filed NOV. l2.A 1952 R rS M T W m M ,../r

.AM .MM Cl p/ N K m7 GB E R RA F. WARRY Aug. 7, 1956 HOISTS 5 Sheets-Sheet 5 Filed NOV. l2, 1952 REGINA@ .FRANK WARRY By AGENTS United States Patent O HOISTS n Reginald Frank Warry, Feltham,-England, assignor to R. F. Warry Limited, Feltham, England, a British company i Application November 12, 1952, Serial No. 319,948

Claims priority, application Great Britain November 13, 1951 4 Claims. (Cl. 187-11) supports a horizontal load carrying platform under the control of a power unit carried by the hoist.

In known types of transportable-hoists the means employed for bringing the column to the upright position and l maintaining it therein constitutes quite a substantial portion of the cost of the hoist, vvand one object of the present invention is to provide a transportable hoist `which can be erected for use and lowered for transport by aquite simple operation without the necessity of expensive accessoriesl for obtaining the desired result. i' f A further object of the present invention is to obviate the necessity of jacks, foldable struts and other expensive accessories for maintaining the column in the operative upright position.

A still further object of the present invention is to provide a hoist which can handle loads such as required in building and like workl to a useful height and yet can be manhandled easily into operative position easily lowered in comfort by two men. v

Briefly, in accordance with the invention, a able .hoist comprises a column with a base framepositioned on one end to support the column in a vertical position. A power driven platform is sldablyaixed to the column and wheels are provided on an axle positioned onthe column for permitting the hoist to be moved. The wheels and axles operate with other means as fulcra which zontal and vice versa. i

lIn order that the invention may be clearly understood andreadilycarried into effect drawings are appended heretorillustrating an embodiment thereof, and wherein:

Figure l is a front perspective view and in operation. n.

Figure 2 is a broken perspective side elevation. view showing the hoist being lowered, andin which the hoist isA shown supported by two fulcrum points.

Figures 3, 4 and 5 are diagrammatic side elevation views `showing three of the dilerent positions of the hoist during raising or lowering.

v Figure 6 is a front elevationand Figure 7 a planof the top ofthe hoist. 1

Figure 8 is a section on the line VIII-VIII of Figure6.

`Figures 9 and 10 are rear and sideelevation-'views respectively of the platform structure, and

Figure l1 is a detail broken perspective view showing the safety device for the hoist platform.

.Referring to the drawings, the column comprises four angle section bars, a front pair'of which 1, 1 are truly of the hoisterected perpendicular to a base frame y2, the remaining pair 1a, 1a being preferably converged at a small angle upwardly to-- a transverse oblong top frame 3.of the hoistcolmn,

and :equally transportrice the column being strengthened by transverse and diagonal struts 4 and 5 respectively. The four angle section bars of the column are welded to an intermediate pair of forwardly projecting channel or double angle section stiftening bars4 2l) of the rectangular base frame 2 composed of angle section bars and having a rear transverse member 2b substantially co-planar with, and having joined thereto, the rear angle section bars la of the hoist, the base frame projecting bilaterally symmetrically relatively to the hoist and having aquite pronounced forward overhang, the arrangement being such that the front transverse bar 2c and the two side bars 2a of the base frame are substantially in the same vertical planes as the front and side edges respectively of the platform 7 which is carried up and down the front angle bars 1 of the hoist column. Diagonal side struts 6 extend from the rear angle section bars of the column to the rear corners of the base frame.

By suitable dimensioning of the base frame 2 and other parts yof the hoist framework and the platform, the hoist,

, onceerected, will remain upright during raising and lowering of the loaded platform, as the centre of gravity of the loaded platform 7 will pass through the base frame in advance of the vertical plane containing the front angle bars 1 of the column.

As indicated in they preamble of this specification the hoist has a number of fulcra which are used in a given sequence to afford a number of fulcra about which the hoist is manhandled from the erected to the substantially horizontal position and vice versa, and in the example now 'being described the fulcra can comprise (A) the rear transverse edge of the base frame i. e. the lower rear corner of the angle bar member 2b, (B) a transverse` horizontal bar 8 spaced in rear of the column and above the plane of the base frame, and (C) the axle 9 of a pair l of road lwheels 10 disposed above and in rear of the secv permit the hoist to be tilted 4from the vertical to the horiond mentioned fulcrum integer, so that in lowering the hoist for it to become supported by the road wheels, it is necessary only to manhandle the hoist about the first mentioned fulcrum (A) rearwardly until the second mentioned fulcrum (B) as shown in Figure 2 also engages the ground, and this can be done easily by one man lifting at the front of the base frame 7 and one man pulling rearwardly on the column, with a hoist up to as high as forty feet and designed so as to be capable of handling 'easily loads for the normal requirements of building, e. g. l

' for raising by its travelling platform in the neighbourhood often hundredweight.

InV the ylatter mentioned position of inclination of the hoist lthe hoist will remain at the rearwardly inclined position supported on fulcra (A) and (B), and thereupon by further easy manhandling the hoist will be tilted further rearwardly about the secon-d mentioned fulcrum (B)L so as to raise the first mentioned fulcrum (A) off the ground andto bring into contact with the ground the pair of road y"wheels 10 as shown in Figure 3, so that the hoist will now bes'upported by the road wheels 10 and the second mentioned fulcrum (B) v as shown in Figure 4, and only a slight manual effort will be required to lift the second mentioned fulcrum (B) clear of the ground into the position shownin Figure 5. The hoist can now be towed or pushed along the ground supported upon the wheels as shown in Figure 3, it being understood that when the hoist is in u se the wheels and the fulcrum (B). are disposed in rear of the hoist column clear of the ground as shown in Figure l.

By way of example, assuming the hoist column hasa minimum height of about twenty-three feet and is in the plane containing the second mentioned fulcrum (B) can PatentedvAug. 7, 19561 be about one foot four inches above ground level and about seventeen inches in rear of the column, this being obtained by welding to the rear angle bars of the column a pair of horizontal side bars 11 of about seventeen inches long and strutting the side bars by diagonal angle bars 12 extending upwardly and rearwardly from the rear corner of the base frame to the free ends of the side bars, additional strutting being obtained by upwardly and forwardly inclined angle bars 13 welded to the said pair of side bars and to higher positions along the rear angle bars of the hoist column. The said pair of side bars are spanned by the transverse horizontal bar 8 comprising fulcrum (B) which engages the ground at the completion of the first tilting operation, this bar having the additional advantage of affording a foot-rest for an operator to stand on when pulling the hoist rearwardly so as to lend his weight to the rearward inclining of the hoist column.

The third mentioned fulcrum (C), i. e. the said axle 9 of the two road wheels is, in the erected position of the hoist, in a horizontal plane about four feet two inches above ground level, and the axle bar 9 is spaced about two feet four inches from the rear of the column, the axle bar 9 being supported by triangulated side struts 15 and 16, it being preferred to weld the lower two members 15 of these triangulated side struts 15 and 16 to the hoist frame at positions close to the junction of the upper ends of the upwardly and forwardly inclined struts 13 connected across the bar 8, i. e. the second mentioned fulcrum (B) and the rear of the hoist column, the remaining two members 16 of the triangulated strutting for the wheel axle extending upwardly and forwardly from the axle to the hoist column at about 60 to the lower elements of the triangulated strutting.

The distance across the said two wheels 10 is preferably greater than the length of the bar 8 so that the Wheels project symmetrically opposite sides of the column and are located in vertical planes outside the sides of the hoist column, e. g. as shown, approximately midway between the ends of the bar 8 and the outer side members of the base frame, and consequently the said triangulated strutting for the wheel axle is diverged rearwardly outwardly away from the column.

To keep the centre of gravity as low as possible and thereby assist in maintaining the column upright, the power unit, which can be a low horse power internal combustion engine 17 as shown, or an electric motor, with a winch drum 18 driven by the engine, is supported on an engine bearer 19 secured across fore-and-aft channel sec-` tion bars 20 between the front and rear angle bars 1 and 2, so that the predominating mass of the power unit and winch drum can be regarded as bounded by the planes joining the angle section members of the column, although there may be a slight uni-lateral overhang of the engine and petrol tank 21 as shown, care being taken however to keep the centre of gravity of the assembly of engine, winch drum, associated clutch gear 22 as near the vertical centre line of the column as possible,

The platform 7 is pulled upwards along the front angle bars of the hoist column by a cable 23 fed from the winch drum 18 of the power unit and carried over a grooved pulley 24 supported in a fork bracket 25 carried at one end of a locating bar 26 (see Figures 6, 7, and 8) fitted snugly between transverse frame members 3a and 3b of the top frame part 3 and clamped in position by a centre bolt 26a passed through a centre cross-bar 3c welded across the bars 3a and 3b and fitted with a lever type head, or alternatively nut, 26a. The fork 24 has a base plate 24a welded to one end of the bar 26, the other end of this bar having welded across it an angle bar 27 carrying on its inner face a channelled arch 28 over which is guided the track of the winch cable 23 after it has passed from the pulley 24 under a pulley 29 carried by the frame of the platform 7, and from which arch the cable is carried to anchorage means in rear of the hoist. anchorage means can comprise a pair of horns 30 on a bar 31 welded at its inner end tothe rear end of the angle bar 27 and carrying at its outer end a pllley 32 over which is guided a manually controlled pull-cable 33 pulled at one end by an operator standing on the ground for controlling the raising and lowering of the platform. It is preferred to provide a substantial surplus of cable 23 and 33 which can be wound upon the anchorage means 30 and pegs 34 or other suitable means reqeetively to enable the height of the column to be adjusted by tho addition thereto of one or more extensions, it being understood that the first mentioned pulley 24 and the arcuate guide 28 by being carried in a detachable manner enables them to be removed and then applied to the extension alxed to the column.

The platform 7 is carried by a pair of angle bars 35 welded at their inner ends to a pair of solid side bars 36 welded to and projecting forwardly from a pair of upstanding angle bars 37 (see Figures 9 and l0) bridged at their upper ends by a cross bar 38, the solid bars 36 projecting rearwardly of the bars 37 to receive struts 39 welded at their upper ends to blocks 40 welded to the inner faces of the angle bars 37 in which are located journal bushes for spindles of two flanged rollers 4l which track against the rear faces of the outwardly directed limbs of the angle bars l of the column. Another, and lower, pair of flanged rollers 41a carried by a shaft 42 supported in bushes in the uprights 37 of the platform frame roll against the front faces of the two angle section bars'at the front of the column.

A safety device is provided to arrest descent of the platform in the event of the cable 23 breaking, and this comprises a loose substantially horizontal bar 43 nor mally abutted against a fixed horizontal angle bar 44 of the vertical frame of the platform frame, the ends of this loose bar being apertured or provided with eyes to receive the upper ends of two coiled tension springs 43 anchored at their lower ends to the lower part of the platform frame, and the cable pulley 29 being carried by the forked upperend 46a of a rod 46 slidable through the bar 44 and` another bar 47 and fitted at its lower end with a nut 46b abutting against the loose bar 43. By this means, normally the springs 45 are overcome by the tension on the cable 23 due to the load of the platform, but will reassert themselves upon such tension being released due to thecable breaking or coming adrift to pull the loose bar 43 to the position shown in Figure 9. One end of this spring loaded bar 43 is connected by a link 48 to a vertical solid rectangular section friction bar 49 abutted at its front facel against a pair of short angle bars 50 welded to the inner face of one of the uprights 37 and slideable against the front face of the adjacent hoist angle bar 1, a depending lug 51` of the cross bar 38 acting as a lateral stop for the friction bar 49, the top of bar 4 normally abutting against the cross bar 38. A boss 52 is welded transversely across the mid-vertical position of the vertical elongated oblong bar 49 and in this boss is journalled n stout pin 53 fixed to and projecting laterally from the front end of a thick square-section block 54x, a diamond or square section lateral boss 35 projecting laterally-froml the rear end of this block 54. The block 54 rocks by its lower face on a fulcrum pin 54a welded to the upright of the platform frame. The square boss 5S acts as a diamond or square cross-section wedge member for` wedging by one edge against the rear face of the hoist member l.

In the eventof the cable 23 breaking or coming adrift the said spring loaded har 43 will tend to move away from the cross bar 44 of the platform frame and this gives a tilting lead to the said square section block 54 vin the aforesaid linkV 48, thus causing the diamond section abutment 55 at rear end of the pivoted block 54 to bite hard against the rolt face of the appropriate upright 1 of the columatbe additional gripping or seizing action beine obtained by reason of the` aforesaid oblong s bar 49 which bears against the front face of the flange of this upright. Immediately following the initiating ofV thev gripping or biting action of the diamond section wedging member 55 and the oblong member 49 upon the said upright, the said loose horizontal bar 43 has imparted to it a slight tilt about the spring loaded end remote-from the end connected by the said link 48 to the bar 49, and this results in a highly elicient .gripping action of members 49 and 55 against the column member 1. The platform will drop slightly until the top cross bar 38 abuts against the top of the vertical bar 49. The gripping action is enhanced in proportion to the load on the platform and consequently affords perfect security against accidental descent of the platform due to the cable breaking or coming adrift.

To enable the safety device to be actuated by hand to lock the platform 7 in a selected raised position, e. g. at the top of the column when fitting an extension to the column, the rear end of the block 54 is fitted with a handgrip 56 by which the safety device may be brought into operation.

It is preferred to control the ascent and descent of the platform from ground level, and for this purpose a clutch lever 56 of the power unit is operated by a substantially horizontal pull rope 57 which is pulled slightly in advance of the rope 33 by an operator standing alongside the hoist to couple the power unit to the winch on which the platform cable is wound, these two ropes being connected to a common handle, with normally a slight slack in the rope 33. To obtain a positive stopping of the drive of the switch when the platform reaches nearly the top of the hoist or any other predetermined position, one of the uprights of the platform carries a lateral or rearwardly extending guide bar which is apertured to receive the rope 33 which near the top of the column has fitted thereon a collar adjustable along it to serve as a normally fixed abutment to be engaged by the member on the platform which slides over the cable so as to positively operate the clutch to disconnect the engine from the winch drum.

The proportions and vertical dimension of hoist column and the base frame and distribution of masses as hereinbefore described and illustrated, are, without any extension to the top of the column, such that during a tilting operation the centres of gravity will, in the positions shown in Figures l to 4, pass approximately along the broken vertical line G shown in each figure. Thus very little strain is thrown on an operator in raising or lowering the column as shown in Figure 2, whilst by reason of the forward overhang of the base frame a convenient additional leverage during raising, and restrainlng effort during lowering of the hoist, is afforded for an additional workman holding the front cross bar of the base frame. Also, as previously indicated, the cross bar 8 comprising the fulcrum integer (B) affords a convenient footrest for an operator to stand on when about to pull the hoist rearwardly from its upright position.

I claim:

l. A transportable hoist comprising a column, a base frame rigidly connected to one end of said column for resting on the ground to support said column in an upright position, a power driven platform slidable up and down the column, a pair of wheels to support the hoist at a point towards that end of said column to' which the base frame is connected and at least one means between said wheels and said end of said column providing at least one fulcrum point about which the column may be tilted during movement from the horizontal to the upright position and vice versa.

2. A transportable hoist of the type including a vertical column with a base frame for resting on the ground when the column is upright and a power driven platform slidable up and down the column, comp-rising three rearwardly disposed ground engaging fulcra spaced vertically from each other at the lower part of the column for the 6 manual erecting and lowering of the column, said fulcra being spaced: rearwardly relatively to each other that, when theV hoist is tilted from a vertical to a substantially horizontal position of the column and vice versa, the fulcraare successively Lbrought into positions at which said fulcra are in Aturn supported from the ground whereby `during a complete raising or lowering operation the column acts as a lever of the rst order, the longer limb of the lever for each fulcrum in use being the part of the column from the top of the vcolumn to the fulcrum in use, the first of said fulcra about which the hoist is tilted during the operation ofraising the hoist to an upright position being inthe 'formof a wheel axle and a pair of wheels mounted onsaid axle to support the hoist during the transport of tlie hoist from one'site to another, the final fulcrum about which the hoist is tilted during the operation being at the rear edge of said base frame, and the third of saidfulcra being located intermediate said first and l final fulcra.

3. fA transportable hoist of the type comprising a vertical ycolumn with a base frame for resting on the ground when the columny is upright, comprising a column, a platform slidable up and down the front side of the column, a power unit at the base of the column to drive the platform, a base frame projecting forwardly from and xed to the 'lower end of the colunm, so that the hoist structure is of elongated L shape in side elevation and the centre of gravity due to the load of and any load carried by the platform must pass through the base frame between the front of the base frame and the column whereby the hoist is self-supporting when its base frame rests on the ground, and fulcra integral with the hoist located so as to serve as successive supporting fulcra for the hoist about which the hoist can be tilted to the upright position from a substantially horizontal position and vice versa, said fulcra being respectively formed by the rear edge of said base frame, a transverse bar disposed to the rear of said column in a plane parallel to said base frame and passing through said power unit and a transverse axle disposed to the rear of said column in a plane which is parallel to, and spaced upwardly from, the rst mentioned plane and a pair of wheels rotatably mounted on said axle and dimensioned to contact the ground when the hoist is lowered about the fulcrum formed by said transverse bar and said rear edge of the base frame is raised from the ground and to serve, when the hoist is further lowered to raise said transverse bar from the ground, as the sole support for the hoists, said axle being disposed so that the vertical plane through the center of gravity of the hoist passes substantially through said axle when the hoist is solely supported by said wheels and said column is horizontally disposed.

4. A transportable hoist of the type comprising a vertical column with a base frame resting on the ground when the column is upright, comprising a column, a platform slidable up and down the front side of the column, a power unit at the base of the column to drive the platform, a base frame projecting forwardly from and fixed to the lower end of the column, so that the hoist structure is of elongated L shape in side elevation and the centre of gravity due to the load of and any load carried by the platform must pass through the base frame between the front of the base frame and the column whereby the hoist is self-supporting when its base frame rests on the ground, and fulcra integral with the hoist located so as to serve as successive supporting fulcra for the hoist about which the hoist can be tilted to the upright position from a substantially horizontal position and vice versa, said column including uprights at the front corners thereof, rollers on said platform in rolling contact with said front corner uprights, cable means driven by said power unit to effect movement of said platform along said column, and a safety device for arresting the movement of said platform including a normally horizontal bar, a fixed abutment, on said platform, means connected to said cable means and bar to urge the latter to its normally horizontal position against said abutment in response to tension in said cable means, spring means connected to said bar and yieldably urging the latter to a tilted position away from said abutment, said spring means being normally Overcome by the tension in saidcable means, a verticall frie-` tion bar disposed adjacent and parallel to a` face of one of said corner uprights, a braking member pivoted at one end on said friction bar and extending transversely across said one comer upright, a wedge-likeI projection extending from the other end of said braking member into close proximityy to the' face of said one upright opposite the first mentioned face of the latter and adapted to wedge against said proximately located face of the upright so that the latter is disposed between said friction bar andy wedgelike projection, means forming a pivot for said braking member on said platform, another abutment on said platform against which said friction bar normally abuts 11pwardly, means connecting said normally horizontal bar to said friction bar so that the tilting of said horizontal bar, in response to the failure of tension in said cable 20 means, lowers said friction bar and rocks said braking member to firmly press friction bar and wedge-like member against the opposite faces of said corner upright, the platform then dropping slightly so that said other abutment again engages said friction bar and the weight 0f the platform further maintains the gripping engagement of said friction bar and wedge-like member with said one corner upright.

References Cited in the le of this patent UNITED STATES PATENTS 1,208,117 Frost Dec. 12, 1916 1,408,522 Laue Mar. 7, 1922 1,542,327 Slingsby June 16, 1925 1,558,042 Druschel Feb. 7, 1928 2,277,302 Chcnette Mar. 24, 1942 2,482,211 Reichardt Sept. 20, 1949 2,493,824 Moros Jan. 10, 1950 FOREIGN PATENTS 676,191 Great Britain July 23 1952

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