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Publication numberUS3044819 A
Publication typeGrant
Publication dateJul 17, 1962
Filing dateMay 19, 1961
Priority dateMay 21, 1960
Publication numberUS 3044819 A, US 3044819A, US-A-3044819, US3044819 A, US3044819A
InventorsPierre Simon
Original AssigneePierre Simon
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Sheet-metal handling apparatus
US 3044819 A
Abstract  available in
Images(2)
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Claims  available in
Description  (OCR text may contain errors)

July 17, 1962 s. PIERRE SHEET-METAL HANDLING APPARATUS 2 Sheets-Sheet 1 Filed May 19, 1961 July 17, 1962 s. PIERRE SHEET-METAL HANDLING APPARATUS 2 Sheets-Sheet 2 Filed May 19, 1961 United States atet 3,044,819 Patented July 17, 1962 SHEET-METAL HANDLING APPARATUS Simon Pierre, 17 Ave. des Violettes, Montfermeil, France Filed May 19, 1961, Ser. No. 111,233 Claims priority, application France May 21, 1960 Cnims.l (Cl. 294-88) The conveying and hoisting of cumbersome objects and products, for example by using travelling cranes, gantry cranes, jib cranes, hoists and the like is attended by complicated problems concerning notably the stowing and steadying operations involving necessarily long handlings and the intervention of several operators.

It is the essential object of this invention to avoid these drawbacks and tol provide to this end a gripping apparatus adapted to be used in conjunction with a hoisting and/ or conveying machine, this apparatus being characterized in that it comprises hook-carrying arms grouped in face to face relationship to constitute two assembiies each comprising at least one pair of arms and one pair of parallel link-systems connecting said arms to a frame supporting afpower unit having its output shaft coupled to a mechanism adapted to move said assemblies toward and away from each other, said frame being furthermore provided with means for suspending it from a hoisting or Iconveying apparatus.

With these combined arrangements there is obtained an apparatus adapted to be remote controlled from a central station for gripping a load, displacing it and iinally laying it down without necessitating any manual intervention, but its essential advantage resides in the fact that the two assemblies cooperate with each other like jaws which, due to the provision of the aforesaid parallel-link systems, move in directions parallel to themselves instead of travelling along curved paths as in conventional arrangements using jaws ulcrumed albout a common axis. Thus, the gripping hooks have always the same inclination irrespective of the relative spacing of the two assemblies.

Other features and advantages of this invention will appear vas the following description proceeds with reference to the accompanying drawings, it being understood that changes in the precise embodiment of the invention herein disclosed may |be made within the scope of what is claimed without departing from the spirit of the invention.

In the drawings:

FIGURE l is a perspective view showing an apparatus constructed according to the teachings of this invention;

FIGURE 2 is another perspective view showing the apparatus during the lifting of a stack of metal sheets or plates, the gripping larms being designed dierently;

FIGURE 3 is a cross-sectional view showing a gripping arm of the apparatus illustrated in FIG. 2;

FIGURE 4 is a fragmentary perspective view of a modified embodiment of the 'apparatus of this invention; and

FIGURE 5 is a longitudinal section showing the coupling device provided between the power unit or motor and the gripping mechanism.

As illustrated in the drawings, the apparatus of this invention comprises arms 1, 2 and 3, 4 bent at right angles Iat their upper portions to profvide corresponding horizontal members 1a, 2a, 3a, 4a. At their lower ends these arms terminate with hook-like portions 5, 6 and 7, 8 and are grouped in face to face relationship to constitute two identical assemblies. Pairs of parallel links 9 and 10, 11 and 12, 13 and 14, 15 and 16, .are pivoted on the one hand on the upper portion-s 1a, 2a, 3a, 4a of the arms, by means of pivot pins 26, 27, 28 and 29, and on the other'hand on a frame 17, each pair of links constituting a parallel motion system.

Mounted on the frame' 17 is an electromotor 1'8 rotatably driving through a coupling device to be described presently with reference to FIG. Sfa screw 19, a' reducing gear also acting as a stress limiter as will be explained presently. Engaging the screw 19 is a nut-forming socket 21 provided with ears 22 on which are pivotally mounted relatively short links 23, 24 each connected toan arm and parallel-link assembly. The short links 23, 24 are pivotally attached to pairs `of divergent arms 23a, 2317 and 24a, 24b respectively, the outer ends of these divergent arms being welded -by pairs on cylindrical hollow sleeves 3S, 36. These sleeves engage respectively cylindrical rods 37, 38 interconnecting homologous links 9, 11 and 13, 1'5 of the parallel-link systems of eac-h assembly.

The above-described apparatus can be hoisted and dis-V placed by means of any suitable apparatus such as a hoist 39 of which the hook 4t) engagesa loop 41, the side branches 41a of this loop extending downwards and being surrounded by coil compression springs 41b disposed between the top of frame 17 and relevantV end nuts 41C. Thus, when the apparatus lifts a load, the springs 41h are compressed and may actuate electric switch means (not shown) inserted in the energizing circuit of the motor 18 to avoid any untimely or faulty operation by opening this circuit automatically when the apparatus is loaded.

The hoist 39 is provided with a current outlet 42 fed through a conductor 43. The motor 18 is supplied with current through another cable 44 provided wit-h a plug 45 tting in the outlet 42.

To impart a sutiicient rigidity to the apparatus, the pairs of links 9 and 1110 and 12, 14 and 116, 13and 15 are interconnected through rods 26, 27 and Z8, 29. For the same purpose, the rods 27, 28 receive bracing members 30, 31 and 32, 33 each adapted to stillen one member of the parallel-link system.

In the alternate embodiment illustrated in FIGS. 2 and 3 of the drawings the arms v1, 2, 3 land 4 are provided with aV plate 67 bolted thereon at 68, the inner vertical edgeg67a of each plate 67 being recessed in relation to the hook 5 and projecting somewhat from the arm face which is to engage the load to be hoisted and conveyed. Thus, when the registering pairs ofarms of the apparatus are moved toward each other for hoisting a load, the edge 67a `of each arm engage the load and prevent it ffrom moving longitudinally. In fact, it is a frequent occurrence that the load slips and falls when the apparatus is moved horizontally, for example by means of a gantry crane, for the load supported by the apparatus has a considerable inertia in relation to the travelling hoisting uni-t of the gantry crane and therefore travels with a certain time lag, thus causing the load suspended from a cable or chain to swing more or less.

In certain applications of the apparatus of this invention, it is advantageous to move the arms of a same assernbly toward or away from each other in `order to ada-pt them to loads of different dimensions, for example in the case `of stacks of metal sheets or plates wherein wooden strips separate the superposed sheets or plates. This result may -be obtained with the `embodiment illustrated in FIG. 4. In this 'case the branches of each parallel-link system consist of a plurality of -sections pivotally interconnected about axes extending at right angles to the sections and located in the plane of the parallel-link system concerned, the arms of a same assembly being interconnected through extensible means.

Thus, as shown in FIG. 4,- the links 9, 10 are each divided into three sections 9a, 9b and 10a, 10b, 10c, and likewise the links 13 and 14, are divided into three sections 13a, 13b, 13a and 14a, 14b, 14e. The sections of a same link are pivotally interconnected about pinsi50, 51, 52, 53, `54, 55, S6 and 57. The arms pertaining to a same assembly (1, 2 onV the one hand and 3, 4 on thek 9 other hand) are interconnected through cross members 58, 59 (the cross members rigid with arms 3 and 4 are not shown to simplify the figure) each rigid with the ar-ms and sliding by pairs in `a sleeve 60, 61 of corresponding configuration.

When it is desired to spread apart the arms of a same assembly, the operator acts manually upon these arms and the branches of the parallel-link systems assume for example the position shown in chain-dotted lines. The cross member `53 slides within the sleeve 60 and the arms may be locked in this different selected position through any known and suitable means.

According to a `modified embodiment the upper portions 1a, 2a, 3a, 4a of arms 1,2, 3, 4 are not secured on the rods 26, 27, 28, 29 but formed with two holes each engaged by these rods so that the arms may slide therealong, their axial movements being limited on one side by the links of the parallel link systems and on the other side by the bracing members 30-33. Since each assembly comprises two arms mounted on the aforesaid rods 2649, the permissible range of adjustment is equal to twice the distance between the links and the -bracing members. The arms are at their minimum relative spacing when each of them engages a bracing member, and at their maximum relative spacing when each of them engages the links of the parallel-link Systems.

The apparatus described hereinabove with reference to two forms of embodiment operates as follows:

This hoisting apparatus equipped with a hoist or like device 39 and a hook 40 `is brought yabove the apparatus of this invention. The hook 40 engages the loop 41 and the plug is inserted into the current outlet 42. Thus, the apparatus is brought above the load to be hoisted and/or conveyed and the motor 18 is energized -in order to rotate the screw 19 in the direction corresponding to the upward travel of the socket 21, so that the short links 23 and 24 move the rods 37, 38 toward each other. These rods cause the links of the parallel-link systems to pivot, and thus the two assemblies comprising the arms 1, 2, and 3, 4 and their hooks are moved toward each other. On the other hand, when the motor 18 and screw 19 are rotated in the opposite direction .the pairs of hooks are moved away from each other. It is Worth pointing out that the Karms remain constantly parallel to themselves when they move outwardly or inwardly, so thatthe hooks remain horizontal and the load transported by the apparatus is constantly supported with the same efficiency, irrespective of the degree of relative spacing of the arms.

Now reference will be made to FIG. 5 to describe the coupling device interposed between the motor and the gripping mechanism. In fact, during the conveying of the load, for example a stack of metal sheets or plates, the

` arm assemblies 1, 2 and 3, 4 tend to move toward each other under the influence of the weight of this load, so that the gripping mechanism produces a self-clamping action. This increase in the clamping force makes it necessary to exert a considerable torque on the motor shaft when releasing the load. With this device the arms and load `are safely released.

In FIG. 5 the motor (not shown) drives through a set of belts 71 a bell-shaped member 72 constituting the driving member of the coupling device. Inside this bellshaped member 72 is a ball-bearing 73 retained in position by set screws 74, this ball-bearing being carried on the other hand by an intermediate sleeve 75 secured on the frame 17 of the apparatus by means of screws 77.

Mounted inside the sleeve 75 are a pair of ball-bearings 78, 79 carrying the shaft 80 rigid with the screw 19. The upper end of shaft 80 projects within the frame 17 and has wedged thereon a handwheel 81 for manually controlling the rotation of the screw 19 for example when it is desired to release the arms by hand, in case of motor or current failure.

A disk 82 solid with the shaft 8f? carries on its outer periphery a radial lug 83 engageable by a pin 84 screwed in the bottom of the bell-shaped member 72 driven from the engine. This disk 82 constitutes the driven member of the coupling device.

When the load has been clamped between the arms, the pin 84 contacts the lug 83 on one side thereof in order drivingly to rotate the screw 19. When it is desired to release the load, the electromotor is fed in a direction to cause the bell-shaped member 72 and therefore the pin 84 to revolve firstly alone, as the pin 84 moves away from the face of lug 83 which it had previously engaged.

After the pin 84 has revolved through almost a complete revolution it engages the other face of lug 83 and the shock thus applied to the disk 82 and therefore to the screw 19 releases the device instantaneously and therefore permits the unclamping movement of the arms.

The safety feature obtained during the hoisting and conveying movements ,as well as the certainty of properly holding the objects to be transported result from the weight of these objects themselves. As a matter of fact, no accidental movement of the arms away from each other can take place due to their specific shape and to the direction in which the gravity forces are exerted. Even an accidental starting of the motor will not divaricate the arms since the screw 19` is driven through belts calculated to slip when the gravity effort exceeds a predetermined value.

The apparatus according to this invention may be used for transporting rigid or semi-rigid objects, such as sheet metal stacks, steel bars, tubes, paper rolls, logs, vehicles, etc. With this apparatus, cold or hot, fragile or sturdy objects can be handled indifferently while eliminating any risk of scoring or damaging them as frequently observed when conventional cable hoisting means are used.

Of course, this invention is not limited to the few forms of embodiment shown and described, as many 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 is:

l. A gripping apparatus comprising pivoted arms for conveying and hoisting different loads, notably sheet metal stacks, which comprises a frame, hook-carrying arms supported by said frame and grouped in face to face relationship into two assemblies, each assembly comprising at least one pair of arms, deformable parallel-link systems pivoted on the one hand on said frame and on the other hand on each one of said arms, a motor carried by said frame, means operated from said motor for moving said two arm assemblies toward and away from each other in order to grip and release the load respectively, and a coupling device disposed between said motor and said means for moving said arm assemblies toward and away from each other, said coupling device comprising a driving member actuated from said motor and a driven member operating said means, said driving and driven members being such that they permit a free relative rotation through an angle suflicient to cause said motor, when the coupling takes place, t0 attain under no-load conditions a speed suicient to release the arms previously clamped on the load transported by the apparatus.

2. Apparatus as set forth in claim 1, comprising at least one horizontal longitudinal member on which said hook-carrying arms are slidably mounted independently of one another.

3. Apparatus as set forth in claim 2, wherein the movable sides of said parallel-link systems are mounted on the ends of said horizontal longitudinal members on which the hook-carrying arms are slidably mounted.

4. Apparatus as set forth in claim 2, wherein each longitudinal member is common to the homologous movable sides of the parallel-link systems of a same assembly.

5. Apparatus as set forth in claim 1, wherein each hand control wheel mounted externallyrof said frame arm is provided with .a vertical, relatively sharp edge and rigid with said driven member. recessed from the relevant hookl and projecting somewhat from the arm face which is to co-act with the loads References Cited in the file 0f this Patent tobelfxranspotrted. t f th l 1 h b u 5 UNITED STATES PATENTS ppara us as se or 1n calm W erem a e shaped member rotatably driven from said motor has ler a pin secured in its bottom, .a radial lug rigid with said 2284238 Todd Ma 26 1942 driven member being adapted to be engaged on one or 2355086 Lang Ag 1944 the ofhefsidebysaidpm 10 217323248 aegefiJan. '24, 1956 7. Apparatus as set forth in claim 1, comprising a

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US1832409 *Aug 10, 1929Nov 17, 1931Mueller HansBattery carrier
US2229800 *Mar 20, 1939Jan 28, 1941William T DeanTongs
US2284238 *Sep 16, 1941May 26, 1942Todd John WHoist grab
US2355086 *Oct 27, 1943Aug 8, 1944Lang Walter BMarine salvage device
US2732248 *May 27, 1953Jan 24, 1956The Jaeger Machine CompanyLifting device
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3154339 *Sep 14, 1962Oct 27, 1964Louis G KaplanArticulated lifter with substantially constant jaw gripping factor
US3237980 *Apr 6, 1964Mar 1, 1966Country Engineering IncCylindrical object clamping devices
US3796332 *Jul 14, 1972Mar 12, 1974T KawamuraCargo handling equipment by gripping and suspending materials
US4678220 *Feb 14, 1986Jul 7, 1987Gabriel Edwin ZShovel-like coupling devices with automatic material handling features
US5184860 *Mar 12, 1991Feb 9, 1993Potain (Societe Anonyme)Motorized remote-controlled load gripping device
US5403114 *Jun 10, 1994Apr 4, 1995James; Danny L.Barrier module lifting clamp
US6000904 *Feb 16, 1999Dec 14, 1999Schluesselbauer; JohannApparatus for storing and conveying standing, tubular workpieces made of concrete
US6138846 *Mar 17, 1998Oct 31, 2000Mi-Jack Products, Inc.Adjustable expansible load lifting device
US6592320May 7, 2002Jul 15, 2003Diamond Tank Rentals, IncQuick connect/disconnect tank lifting brace and method of use
US6749392Feb 22, 2001Jun 15, 2004Ben A. AdamsQuick connect/disconnect tank lifting brace and method of use
US7134701 *Dec 30, 2003Nov 14, 2006Ronning James MFrame for lifting beams and other elongated loads
US7537427 *Oct 22, 2003May 26, 2009Tygard Machine & Manufacturing CompanyClamping apparatus
US8079799 *May 9, 2007Dec 20, 2011Petersen Industries, IncApparatus and method for lifting containers
US8142131May 11, 2009Mar 27, 2012Tygard Machine & Manufacturing CompanyClamping apparatus
US8328258 *Sep 16, 2009Dec 11, 2012Rolls-Royce Marine AsGripping tool for a crane
US9181067 *Jun 17, 2014Nov 10, 2015The United States Of America, As Represented By The Secretary Of The ArmySuspended payload stability device
US9446933Jan 29, 2015Sep 20, 2016Vacuworx Global, LLCLifter and method for moving traffic barriers
US20040115035 *Oct 22, 2003Jun 17, 2004Edward TygardClamping apparatus
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US20100117390 *May 11, 2009May 13, 2010Tygard Machine & Manufacturing CompanyClamping apparatus
US20110204666 *Sep 16, 2009Aug 25, 2011Andreas KjolCrc tool
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CN105819328A *May 30, 2016Aug 3, 2016黄石市华天自动化设备有限公司Claw-type lifting device
Classifications
U.S. Classification294/198, 294/81.51, 294/62
International ClassificationB66C1/32
Cooperative ClassificationB66C1/32
European ClassificationB66C1/32