US3529736A - Devices for raising loads to permit the handling thereof - Google Patents

Description

P 22, 1970 c. J. P. LEBRE 3,529,736

DEVICES FOR RAISING LOADS TO PERMIT THE HANDLING THEREOF Filed Dec. 31, 1968 I 3 Sheets-Sheet 1 I [a -\T%, "TIA. i f f 7 27 25 25 24 52 20 8 4 9 F2 12 Z7 Z5 24 25.30 Z8 INVENTOR.

CHARLES TIE/1N PIERRE LEBRE BY 0% WM ATTORN Filed Dec. 31, 1968 p 22, 1910 c. J. P. LEBRE 3,529,736

DEVICES FOR RAISING LOADS TO PERMIT THE HANDLING THEREOF 3 Sheets-Sheet 2 54 53 55 INYENTOR CHARLES .TEAN PIERRE LEBRE HTTORNEYS p 22, 1910 J. P. LEBRE 3,529,736

DEVICES FOR RAISING LOADS TO PERMIT 'IHE HANDLING THEREOF Filed D90. 31, 1968 3 Sheets-Sheet 5 62 It E 64 77 IN ENTOR CHRRLES JEAN PIERRE LEBRE nTToleNeys United States Patent US. Cl. 214-390 8 Claims ABSTRACT OF THE DISCLOSURE A device for raising and handling loads comprises a U-shaped wheel frame for surrounding one portion of the load to be lifted, the side-members of the frame being provided with bevelled members pivoting on vertical pins for being inserted under the load. The frame is extensible laterally and longitudinally and its side members carry adjustable bearing plates to be engaged under the load when said load has been lifted by said bevelled members.

The present invention relates in general to devices, notably wheel-mounted trucks, for raising loads and permitting the convenient handling thereof, and has particular reference to a device of this general character which is designed for heavy-duty operation.

When very heavy loads are to be handled without any possibility of gripping, clamping or otherwise engaging them by means of a conventional hoisting and/or transport device such as hoists, fork-lift trucks and other material handling equipments, these loads must firstly be laid on shims, blocks or the like to permit the proper engagement of the conventional hoisting and/ or transport means therewith. This problem arises more particularly in the handling of very heavy machines and crates.

Fitting shims, blocks and the like under these loads constitutes a difficult, time-robbing and delicate operation. In fact, as a rule this operation is carried out by forcefitting, for example by using a sledge-hammer or the like, triangular-sectioned chokes between the load and the floor supporting same; as these chokes are inserted under the load, the bottom of the load is more or less raised off the floor. It is then possible to insert into the gap thus created any suitable hoisting or lifting means, such as ropes, claws, etc., or alternately transport means such as the forks of a lift truck, rollers, etc.

It is an essential object of the present invention to provide a device capable on the one hand of lifting heavy loads very rapidly, with the maximum safety and reliability, without requiring any significant effort, and on the other hand of transporting the thus lifted load.

This device comprises a U-shaped frame adapted to surround at floor level, at least one portion of the load to be lifted, the side members of the frame being provided at their lower portions with bevelled, independently-controlled members pivotally mounted on vertical pivot pins, whereby the rotation of said bevel ed members causes their bevelled edge to be gradually inserted under the load to raise same off the floor. These side members also carry, at a distance from said bevelled members which is adjustable as a function of the length and also of the handling possibility of the load, retractable bearing plates adapted either automatically or under manual control to engage the load from underneath after the load has been lifted by said bevelled members, in order to balance and fully carry the load.

Advantageously the transverse spacing between the side members of the frame is adjustable by telescopically mounting their central portions constituting together the "ice cross member of the U-shaped frame. The central portions of the two side members of the frame are also adapted to slide telescopically in a tubular member permitting a maximum relative spacing of said side members while preserving a perfect rigidity of the assembly. The length of the side arms is also adjustable by means of a telescopic mounting whereby the device can be adapted for lifting loads of various dimensions.

According to an advantageous form of embodiment, each bevelled member may consist of an elliptic cam r0- tatably mounted on a vertical pivot pin supported by each side member of the frame, the bevelled portion of each cam being spiral-shaped to facilitate its gradual insertion under the load.

To permit the transport of the load lifted by the device, the U-shaped frame of the device is provided with retractable wheels adapted, when tilted and caused to engage the floor, to raise the load-supporting frame and therefore to move the load freely. Preferably, a carrier wheel is mounted at the end of each side member of the frame which is opposite said cross member, and a third carrier wheel is mounted on the outer tubular member constituting said cross member, said third wheel being movable along this tubular member so that it can be positioned approximately in the plane containing the center of gravity of the load. Preferably, this third wheel consists of a caster in order to facilitate the steering of the assembly.

The function of the bearing plates carried by the side members of the U-fra-me is to properly balance the load after the latter has been lifted by said bevelled members; these bearing plates may advantageously be pivotally mounted and adapted to be retracted by resilient means when a force is exerted thereon in any direction. These bearing plates may be movable along the side members of the frame so that they can be locked to these members at the location best suited for the load to be lifted.

Each bearing plate comprises a vertical pivot pin mounted for free rotation in the corresponding side member of the frame or in a strap slidably mounted to this arm (according as the bearing plate is fixed or movable therealong), and a foot or base plate rigid 'with said pivot pin and adapted to carry one fraction of the load. The bearing plates are retracted and returned automatically to their operative position by a traction spring anchored with one end to said base plate and with the other end to the side member of the vehicle or to the sliding strap, accordingly as the bearing plate is fixed or movable therealong.

It will be readily understood that according to a specific form of embodiment of the device each side member of the U-shaped frame may comprise two retractable pivoting bearing plates, the bearing plate nearest to the cross member of the frame having a bevelled base plate and being adapted to be actuated for example by means of a hand lever so as to insert said base plate under the load supported directly by the floor. This apparatus is also suitable for easily lifting loads having their bottom face not in direct bearing engagement with the floor, for example crates already separated from the supporting floor by means of shims, blocks or the like. In this case, the side arms of the device are disposed on either side of the crate, the bearing plates collapsing or receding as they clear the shims or blocks, and returning automatically to their operative position so as to project under the bottom of the crate.

According to another form of embodiment, the side members of the U-frame may comprise a convenient gantry-type hoist system adapted to engage the upper end of a hollow portion of the load to be lifted, so as to provide an additional point of engagement for raising 3 the load. This hoist system advantageously consists of two identical and registering members, each rigid with one of the side members of the U-frame of the device, each hoist member comprising a pair of vertical uprights formed with rack teeth and relevant runners provided with spring-urged lock pawls, one of said runners having a manual control lever controlling the lifting motion pivotally mounted thereon, this control lever being opera tively connected to the other runner carrying a suitable cross bar engageable into the hollow portion of the load.

A better understanding of this invention will be had as the following description proceeds if reference is made to the accompanying drawings illustrating diagrammatically by way of example typical forms of embodiment of the invention. In the drawings:

FIG. 1 is a plane view from above showing a first form of embodiment of the device of this invention;

FIG. 2 is a side elevational view of the same device;

FIG. 3 is a longitudinal fragmentary section illustrating diagrammatically the telescopic mounting of the frame of the device;

FIG. 4 is a section showing on a larger scale the bevelled cam member equipping the device of FIGS. 1 and 2;

FIG. 5 is a plane view from above showing a modified form of embodiment of the device of this invention;

FIG. 6 is a side elevational view, with parts shown in section of the device of FIG. 5

FIG. 7 is a plane view from above showing a collapsible pivoting bearing plate provided with a bevelled base plate, and,

FIG. 8 is a side elevational view of the collapsible bearing plate of FIG. 7.

Referring first to FIGS. 1 and 2 illustrating a first form of embodiment of the hoisting device of this invention, this device comprises essentially a U-shaped frame consisting of two L-shaped metal members of rectangular cross-sectional configuration, although any other suitable polygonal cross-sectional shape may be used if desired.

One of these L-shaped members comprises a hollow cross member 1 and a side member 2, and the other L- shaped member comprises a cross member 3 slidably mounted in cross member 1, and a side member 4 similar to side member 2. A central tubular sleeve 5 permits the free sliding movements of the two telescopic cross members 1 and 3 of the frame and comprises at one endsee FIG. 3an inner flange or like peripheral projection 6 adapted to engage the tubular cross member 3 to compensate the difference in thickness between tubular member 1 and tubular member 3, in order to properly guide and preserve the rigidity of the U-frame. The relative spacing of the side members 2, 4 is controlled and adjusted by means of a screw rod 7 engaging with one end an internally screw-threaded tube 8 rigid with the side member 2. The opposite end 9 of screw rod 7 extends through the other side member 4 and is axially rigid therewith but allowed to rotate freely therein. This end of screw rod 7 projects somewhat from side member 4 and is square-sectioned to permit its engagement by a corresponding spanner (not shown).

It is clear that the actuation of the end 9 of screw rod 7 permits of adjusting as will the depth of engagement of said rod 7 into the internally screw-threaded tube 8, and therefore the relative spacing of side members 2 and 4.

Each side member 2, 4 carries in the vicinity of the corner or elbow formed thereby with the relevant cross member 1, 3 an inner strap 10 having pivotally mounted thereon a bevelled member consisting of a rotary elliptic cam 11 underlying said strap 10. This cam 11 has a flat bottom face (see FIG. 4) and a helical cam face 12 connecting the edge 13 at floor level to a wider flat face 14 located at a higher level. This cam is rigid with a vertical eccentric pin 15 rotatably mounted in a socket 16 fitted in a corresponding bore of strap 10. A nut 17 en- 4 gaging the threaded upper projection portion of pivot pin 15 locks this pin 15 against axial move-ment in the socket 16. Overlying said nut 17 is the square-sectional tip 18 of pivot pin 15 which is engageable by a relevant spanner 19 for rotating the pivot pin 15 and therefore the cam 11.

The side members 2, 4 are hollow and have telescopically mounted therein corresponding arms 20 adapted to support retractable carrier wheels for transporting the loads to be lifted. In order properly to support the load on the frame structure, auxiliary load supporting means are provided which are retractably mounted to the end of the telescopic arms 20 in bosses 21 adapted to receive the vertical pivot pins 22 of these supports, of which the horizontal bearing plates 23 rigid with the lower end of pivot pins 22 are adapted to be inserted under the load. These bearing plates 23 are adapted to recede resiliently under the telescopic arms 20 by rotating about their pivot pins 22 and to be locked in their projecting position towards the axial center line of the frame illustrated in FIG. 1 through any suitable means (not shown). At their free end each one of the telescopic arms 20 carries a horizontal pivot pin 24 having pivotally mounted thereon a pair of links 25 having one end provided with a horizontal axle 26 of a carrier wheel 27.

At the opposite end of each pair of links 25 another pivot pin 28 carries a strap 29 supporting a pivot or axle 31 of a roller 30. The strap 29 carries at its end opposite to said roller a hexagonal pin 32 adapted to be engaged by a suitable spanner (not shown).

It is clear than when this spanner is rotated in the direction to pull the hexagonal pin 32 upwards, the strap 29 is pivoted until the roller 30 engages the arm of the load-supporting frame. Continuing this movement will lift the strap 29 and lower the wheel 27 against the floor due to the pivotal movement of links 25 about their horizontal pivot pins 24, the reaction taking place against the rollers 30. When the strap 29 reaches a vertical position the rollers 30 are beneath the pivot pins 28 and the frame of the device is lifted to a height suflicient to permit the displacement of the loaded device on its wheels 27. Of course, to prevent the frame from falling back, the roller 30 must be moved to a position beyond the vertical plane containing the axes of pivot pins 28 and locked in this position by any suitable and known means (not shown), such as a stop carried by one link 25.

A third wheel is provided for imparting the necessary stability to the device. To this end, a slide member 33 is slidably mounted on the frame sleeve 5 so that it can be positioned at any suitable location along this sleeve, this feature being advantageous when transporting a load having its center of gravity somewhat eccentric in relation to the frame structure. This slide member 33 comprises two parallel bracket plates 34 between which a pair of parallel links 37, 38 are pivotally mounted at 35, 36, these links being pivoted in turn at 40, 41 to a vertical caster body 39. The pivot pins 35, 36, 40 and 41 constitute a parallel motion permitting the vertical movements of the caster body in relation to said bracket plates 34 or vice versa.

A vertical pintle 42 is mounted for free rotation in the caster body 34, the lower end of this pintle being rigid with a strap 43 in which the caster 45 is mounted on a horizontal axle 44. A steering bar 46 is pivotally mounted on a pair of links 47 rigid with caster axle 44, the actuation of this steering bar 46 permitting of orienting the caster in the desired direction, i.e. the direction in which it is desred to drive the device.

With this mounting, the caster 45 is constantly in engagement with the floor and the frame is adapted to be lowered or raised with respect to said caster 45 by actuating a hexagonal-sectioned rod 48 carried by the upper ends of links 37.

For operating the device shown in FIGS. 1 and 2 the following procedure may advantageously be adhered to.

Assuming the device in the position shown in FIG. 2, i.e. with the frame supported by the floor through the bevelled cams 11 and the auxiliary bearing plates 23, the device is engaged around the load, after adjusting the longitudinal and transverse dimensions of the frame as a function of the load dimensions. Under these conditions the bevelled cams 11 are retracted and the auxiliary bearing plates 23 are likewise retracted under the frame. Then the two cams 11 are actuated in succession. It will be readily understood that the rotation of each cam 11 causes each cam face 12 to be inserted under the load. After a rotation of about 90 of said cam, the fiat top face 14 thereof is inserted under the load. Then the hexagonal rod 48 is actuated in order to raise the right-hand portion of the frame (as seen in FIG. 1) with respect to the front caster 45. This upward movement of the frame, together with the load carried thereby, by means of the cams 11, is sufficient to form between the floor and the underface of the load a space sufficient for permitting the resilient insertion of the auxiliary bearing plates 23 under the load, these plates 23 being then locked in their operative position.

It will be seen that if the gap thus formed between the floor and the underface of the load were not sufiicient to permit the insertion of plates 23, it would only be necessary, after raising the right-hand portion of the frame as explained hereinabove, to insert a' shim, block or like member under the load at a point located substantially mid-way between earns 11 and plates 23. Thus when the hexagonal rod 48 is operated in the opposite direction, the right-hand portion of the frame will be lowered so as to cause the load to tilt about the shim or block, thus freeing a space suflicient for inserting the plates 23. Then, another actuation of rod 48 will be sufiicient for raising again the right-hand portion of the frame which is now supporting the load. To lift the load completely it is only necessary to lower the wheels 27 by rotating the hexagonal pins 32.

If desired, collapsible auxiliary bearing plates 23 may be used, and in this case the plates 23 recede resiliently by pivoting when an effort is exerted thereon in any direction. The cam members 11 may also be replaced by such collapsible bearing plates provided with a bevelled base plate to permit its insertion under the load. FIGS. 7 and 8 illustrate thus collapsible bearing plate 50 of which the vertical pivot pin 51 can rotate freely within a bearing strap 52 rigid with the frame side member. A traction spring 53 is attached at one end to a point 54 of the base plate 50 and at the opposite end to a projection 55 provided to this end on the frame structure side member 2. The base plate 50 has a bottom face 56 of greater surface area formed along its periphery with a bevelled edge 57 adapted, as already explained, to be inserted under the load when the bearing plate is rotated under the control of a suitable spanner engaging the upper hexagonal-sectioned portion 58 of the bearing plate pivot pin 51.

It will also be understood that these bearing plates, whether of the bevelled or auxiliary type described hereinabove, can move along the side members of the frame so that they can be locked thereto in the position best suited to support the load. These movable bearing plates are mounted somewhat like the plates 50 described hereinabove, except that they are mounted on slide members movable along the side members of the frame and adapted to be locked thereto at any desired location. The use of movable bearing plates is advantageous in that they can be set at properly selected points of 'said side members where they can efficiently hold the load to be lifted, said movable bearing plates being interconnected by an adjustable tension chain parallel to the frame members 1 and 3, thus imparting a sufficient rigidity to the frame when the bevelled bearing plates are subsequently inserted under the load.

FIGS. and 6 of the drawings illustrate another form of embodiment of the device of this invention; in this modified construction the device is equipped with a gantry adapted to engage hollow portions of the load to be lifted. In this specific structure each telescopic side arm 20 constituting the extension of side members 2, 4 of the U-frame has secured thereto by bolting, welding or otherwise a pair of vertical parallel uprights 60, 61 provided or formed with rack teeth having the same spacing and horizontal alignment on both uprights. Each upright 60, 61 has slidably mounted thereon a runner 62, 63 on which a spring-loaded pawl 64, 65 is pivotally mounted (the pawl springs being omitted from the drawing for the sake of clarity), the lower end of these pawls being each urged by said springs into a hollow formed between two adjacent teeth of the rack on the relevant upright, so as to position the runner. The front and rear faces of each runner 62 have welded thereto a pair of brackets 66, 67 having secured therein parallel tubular sleeves 68, 69 extending at right angles to the frame side members 2, 4. The sleeves 68 of each one of the two frame side members are interconnected by a squaresectioned bar 70 slidably mounted in said sleeves 68 to accommodate changes in the frames width. Similarly a square-sectioned bar 71 parallel to bar 70 is slidably mounted in the other sleeves 69.

A pivoted control lever 72 is fulcrumed at 73 on runner 63 and has one end pivoted at 74 to a link 75 fulcrumed in turn, at one end, to a strap 76 rigid with the other runner 62. The function of bars 70 and 71 is to be introduced into or beneath a hollow portion of the load to be lifted, and then to be raised until the upper end of said'hollow portion engages the bars 70 and 71. This upward movement of bars 70, 71 and therefore of runner 62 is obtained by lowering the control lever 72 which, by reacting against the pivot pin 73, causes the upward movement of runner 62 along its upright 60. A traction spring (not shown) connects the lower end of runner 63 to the upper end of runner 62 in order automatically to exert a return action thereon and restore the control lever 72 and runner 63 to their upper positions after each upward movement of runner 62. The bars 70 and 71 can be lowered by alternately releasing the pawls 64 and 65. This release may be obtained for example by pulling cables 77 having one end attached to the upper end of pawls 64, 65 and the other end anchored to said control lever 72.

It will be readily understood that this description should not be construed as limiting the scope of the invention since various modifications and variations may be brought thereto without departing from the spirit and scope of the invention as set forth in the appended claims.

What I claim as new is:

1. A device for lifting and handling very heavy loads, consisting of a U-shaped frame including a cross member and telescopic side members adjustable both longitudinally and transversely as a function of the dimensions of the load to be lifted, the free end of each side member carrying a collapsible wheel, means for raising and lowering each wheel relative to its respective side member, a third wheel slidably mounted on the cross member of the frame, the side members of said frame carrying, in the vicinity of their connection to said cross member bevelled members disposed at the floor level, lift means operating in conjunction with said bevelled members to tilt the load about its rear end, means operated in succession for inserting said bevelled members by rotation under the load, and auxiliary collapsible bearing plates shiftable on said side members to any desired and suitable points along said side members and to be inserted under said load when said load has been lifted in order to properly balance the load.

2. A device according to claim 1, wherein the adjustment of the transverse spacing of the side members of said U-shaped frame is obtained by causing cross members each rigid with, and extending at right angles to, one of said side members, to slide in each other, a sleeve provided externally of said cross members being adapted to slide along said cross members and formed with an inner peripheral projection or flange adapted to engage said inner cross members for stiffening the frame structure regardless of the relative spacing of said side members.

3. A device according to claim 1, wherein said bevelled members have the configuration of elliptic cam members adapted to revolve about eccentric axes, each cam being controlled separately for rotation about the relevant eccentric axis.

4. A device according to claim 1, wherein said bevelled members consist of bearing plates each having their foot portion bevelled along its outer peripheral edge, said bearing plates being resiliently connected to the relevant side member of the frame so as to extend normally to said side member in their operative position and to recede resiliently in any direction when they engage an obstacle, said bearing plates being adapted to be actuated manually for inserting their bevelled foot portion under the load.

5. A device according to claim 1, wherein the auxiliary bearing plates which are designed for supporting the load are resiliently connected to the side members of the frame and adapted to extend normally to these side members in their operative position and to recede in any direction when they engage an obstacle.

6. A device according to claim 1, wherein the aforesaid bevelled members are displaceable along the side members of said U-shaped frame and adapted to be locked on said member at a suitable and selected position as required by the shape and dimensions of the load to be lifted, said bevelled members being interconnected by an adjustable tension member for preserving the frame rigidity when said bevelled members are inserted under the load.

7. A device according to claim 1, wherein each one of said side members of said U-frame carries a pair of rackforming vertical parallel uprights on which runners are adapted to slide, one runner constituting a bearing member for actuating a control lever adapted to cause the other runner to rise along the relevant upright, said other runner carrying telescopic bars extending at right angles to the frame side members and adapted to co-act with a hollow portion of the load to be lifted.

8. A device according to claim 7, wherein said runners react or bear against the teeth of said rack-forming uprights through the medium of pawls resiliently urged to their locked position.

References Cited UNITED STATES PATENTS 1,239,771 9/1917 Collis. 3,145,864 8/1964 Arnold

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