MATERIALS HANDLING WITH GRIPPER ARM.docx

8/10/2019 MATERIALS HANDLING WITH GRIPPER ARM.docx

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GRIPPER MECHANISM FOR MATERIAL HANDLING DEVICE:

In the extraction of parts from a press, die casing machine, or the like, the use of mechanical handling

equipment has become widespread. Such equipment generally comprises a frame or arm which is

movable toward and away from the press, and a jaw assembly which is actuated to engage the part prior

to its extraction. Such jaw assemblies commonly utilize a freely pivotal finger which depends from the

rcciprocable carriage, the carriage being actuated by a fluid pressure cylinder and the finger being closed

to a gripping position by its abutment with a fixed stop on the carriage slide. The finger and carriage are

provided with parts-engaging pads or points which can readily engage a projection on the part which lies

in the plane of movement of the carriage. However, the heretofore utilized jaw assemblies are not

adaptable for the extraction of parts in which the projection lies vertically or in any plane other than that in

which the carriage reciprocates.

The present invention provides a new and improved gripper mechanism or jaw assembly for part

extraction machinery generally. More specifically, this invention provides a gripping mechanism whichmakes possible the extraction of a part having a flange or projection which lies askew to the plane of

movement of the material handling apparatus associated with the gripping mechanism.

structurally, the device of the present invention comprises a reciprocable carriage which forms a first

gripping element movable in a planar path into engagement with the part and a second gripping element

carried by the carriage and movable both horizontally and vertically with respect thereto. in the retracted

position of the gripping mechanism, the second gripping element is angularly disposed with respect to the

carriage, so that the part engaging portions thereof are vertically disposed with respect to the similar

portions of the carriage. In the event the part is provided with an upstanding flange which must be

grasped to remove the part, the second gripping element generally overlies the carriage. 'Ihe carriage and

the second gripping element are comovable until the gripping portions thereof are disposed on opposite

sides of the plane of the flange and approximately equidistant therefrom. The carriage and the sec ond

gripping means are now moved relatively so that the gripping portions thereof approach the flange from

opposite sides with the gripping portions finally engaging opposite portions of the flange. Actuation of the

material handling mechanism associated with the gripper assembly can now extract the part from the

machine.

It is, therefore, an important object of this invention to provide a new and improved gripper mechanism for

a material handling device.

atent G p 2,910,321 Patented Oct, 27, 1959 Another important object is the provision of a gripper

mechanism for utilization in the extraction of a part from a press or the like.

It is a further object of this invention to provide an improved gripper mechanism adapted to engage a

flange angularly disposed to the direction of movement of the gripper mechanism.


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Yet another important object is the provision of a material handling mechanism for removing a part from a

press or the like and having a gripping mechanism including a pair of gripper elements relatively movable

both longitudinally and vertically into engagement with opposing sides of a part flange or the like lying

askew to the path of movementof the material handling mech- 'anism.

It is a still further object to provide a gripper mechanism having a longitudinally reciprocable carriage and

a gripping element angularly disposed with respect thereto and interconnected with the carriage through

cam means operative to effect abutment of the carriage and the engaging means with opposite sides of a

flange disposed angularly with respect to the path of movement of the carriage.

On the drawings:

Figure 1 is a side elevational view of a material handling apparatus provided with a gripper mechanism of

the present invention;

Figure 2 is a View similar to Figure 1 illustrating the apparatus in an adjusted position wherein the

gripping mechanism is closed for engagement with a part;

Figure 3 is an enlarged fragmentary side elevational view, with parts broken away and in section,

illustrating the gripper mechanism;

Figure 4 is a sectional view, with parts shown in elevation, taken along planes 4-4 of Figure 3; and

Figure 5 is a sectional view taken along the plane 55 of Figure 3. l

in the drawings: 1

In Figure 1, reference numeral 10 refers generally to a material handling apparatus of the type disclosed

in our earlier-filed, pending applications Serial No.'555, 413 (now issued Patent No. 2,781,136, dated

February 12, 1957), and No. 636,826, filed in the United States Patent Office on December 27, 1955, and

January 28, 1957, respectively, and both assigned to the asignee of this invention.

Generally, the material handling apparatus 10 comprises a fixed frame element 11 carrying a

longitudinally extending guide rod 12 upon which is slidably disposed a second or movable frame 13. The

frames 11 and 13 are relatively telescopically movable through the actuation of a fluid pressure cylinder14, the piston rod 15 of which carries a pinion 16 engageable with a reaction rack 17 on the frame 11 and

an output rack 18 on the frame 13. Actuation of the cylinder 1 1 will effect reciprocation of the frame 13 to

an extent greater than the extent of movement of the rod 15, because of the overspeed gearset 16, 17

and 18, as described in detail in the earlier of our above-identified patent applications.


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The movable frame 13 carries a vertically adjustable side plate 20 upon which is disposed an upper pivot

plate 21. Pivotally connected to the plate 21, as through a pivot pin 22, is a lower pivot plate 23 carrying a

jaw assembly indicated generally at 25. The upper and lower pivot plates 21 and 23 are relatively pivotal

about the 7 axis of the pin 22 and are normally maintained in their generally parallel relation (as illustrated

in Figure 1) by a compression spring 24 interposed between the plates and an adjustable stop 26 carried

by the lower plate 23 and abutting the upper plate 21.

Retraction of the piston 15 within thecylinder 14 will move the frame 13 forwardly upon the guide rod 12,

thus advancing the jaw assembly 25 toward the press or other production machine with which it is being

utilized. At the forward end of the retraction stroke of the piston 15, a roller 27 carried by the lower pivot

plate 23 will abut a swingable abutment arm 28 carried by the fixed frame and having a saddle block 29

disposed in the path of movement of the roller. Abutment between the roller 27 and the block 29 will

cause pivotal movement of the arm 28 about its pivot axis, indicated generally at 3%), and the roller 27

will be depressed to move the plates 21 and 23 from their parallel position to the relatively tilted positionof Figure 2. At the same time, the jaw assembly- 25 will be tilted'to its position illustrated in Figure 2.

Upon retraction of the movable frame 13, as upon extension of the piston rod 15, the jaw assembly will be

swung vertically through the coaction of the arm 28 and the roller 27, so that a part is removed vertically

from the machine. Further extension of the piston rod 15 will remove the roller 27 from the arm saddle 29,

so that further movement of the frame 13 will occur with the jaw assembly tilted and the plates 21 and 23

parallel, as indicated in Figure l. This operation of the mechanism and the tilting of the jaw assembly are

described in detail in the latter of our prior above-identified patent applications.

As best illustrated in Figures 1, 2 and 3, the jaw assembly comprises an upper support rod 31 which is

clamped in a longitudinally and pivotally adjusted position by a clamping bracket indicated generally at 32

and carried by the pivot plate 23. This rod 31 carries at its forward end a depending bracket 33 which

encompasses the forward end of the fluid pressure actuated cylinder 34. The lower end of the bracket 33

fixedly engages a guide rod 35 which projects generally longitudinally of the material handling apparatus

10 and parallel to the cylinder 34. At the forward end of the guide rod 35 an abutment block 36 is

positioned, this block being adjustable longitudinally of the rod 35 through an adjusting screw 37 and

having an upper, rearwardly facing, concave abutment surface 38.

Disposed upon the rod 35 in surrounding relation and adapted for sliding movement therealong is a

tubular sleeve 39 which has superimposed thereon and affixed thereto a carriage indicated generally at

40. This carriage 40 comprises a pair of transversely spaced side plates 41 and 42 (Figures 4 and

adapted to receive therebetween the forward end 43 of a piston rod 44 reciprocably actuatable by the

cylinder 34. Side plates 41 and 42 and the end 43 of the rod 44 are secured together by a transverse

locking pin 45. Intermediate the side plates and generally forwardly of the pin 45 is a generally

rectangular spring saddle block 46 provided with a central slot 47 for a purpose to be hereinafter more

fully described.


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The carriage 40 is provided at its extreme forward end with a pair of gripping pads 48 secured by suitable

means, as by nuts 49, to a transverse plate 50 welded or otherwise secured to the forward ends of the

side plates 41 and 42.

A gripping element or finger 55 is generally superimposed over the carriage 40 with its rear portion,

indicated at 56, being interposed between the side plates 41 and 42. A transverse cam or guide pin 57

secured to the side plates 41 and 42 and projecting through an arcuate guide or cam slot 58 in the arm

cooperates with a lower transverse guide pin 59 to retain the gripper element 55 in position upon the

carriage. interposed between the element 55 and the block 46 is a coiled compression spring 60, the

spring extending into a slot 61 formed in the rear portion 56 of the arm 55.

The forward end 62 of the arm 55 lies substantially normal to the remainder of the arm and depends

therefrom into vertically and longitudinally spaced relation to the plate 50. This end 62 of the arm 55

carries a transverse plate 63 similar to the plate 50 and provided A: with laterally spaced gripper pads 64

which are secured to the plate 63, as by nuts 65. r

The operation of the gripper mechanism would be obvious from a study of Figures 1, 2 and 3. During

initial stages of actuation of the cylinder 34 to extend the rod '44, the carriage 4e and the arm 55 will be

moved forward jointly. The compression spring 60 will maintain the arm 55 in its forwardmost position with

the transverse pin 57 bottomed at the rear end of the slot 58. However, when the lower end 56 of the arm

55 abuts the concave surface 38 of the abutment 36, further longitudinal forward displacement of the arm

55 will be prevented, while the carriage 40 will be free to move forwardly, although impeded by the

compression ot the spring 60.

Further movement of the carirage 40 will effect relative movement between the arm 55 and the carriage,

such movement being controlled by contact of the cam pin 57 with the edges of the cam slot 58. As a

result, the arm 55 is displaced rearwardly relative to the carriage 49 against the compression of the spring

60 and the gripping pads 64 of the arm 55 and 48 of the carriage 40 will approach one another both

vertically and longitudinally. The contour of the slot 53 is such that abutment of the pin 57 with the edges

of the slot will move the depending end 62 of the arm 55 both vertically and longitudinally into substantial

longitudinal alignment with the corresponding end of the carriage 40. The distance between the pads 48

and 64 is such that the pads 64 and 48 are preferably disposed on opposite sides of the plane through

the flange or other portion of the part to be engaged by the pads, at the time of abutment between the

arm 55 and the abutment surface 38. In this manner, the part flange is approached by the pads 64 and 48

from opposite sides, while at the same time the pad 6 4 is moving downwardly into alignment with the

forward end of the carriage 4d. Obviously, the exact path of movement of the pad 64 may be varied by

varying the contour of the slot 58.

Once the part flange has been engaged by the pads 48 and 64, the cylinder rod 15 can be extended to

retract the entire frame 13, jaw assembly 25, and the part from the press. Upon retraction of the jaw

assembly cylinder rod 44, the rear end 56 of the arm 55 is removed from its contact with the abutment


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surface 38 and the spring 66 returns the arm 55 to its position illustrated in Figure 3 of the drawings, thus

releasing the part from the pads 48 and 64. The material handling apparatus is then conditioned for

another cycle.

While a preferred embodiment of my invention has been described above in detail, it will be understood

that numerous modifications may be resorted to without de' parting from the scope of the following claims.

We claim:

1. In a material handling mechanism for the removal of parts from a press, a gripper mechanism for

engaging a vertical flange on the part, comprising a first vertically faced gripping element longitudinally

movable in a planar path into substantially normal engagement with the part flange, a second gripping

element carried by said first element for initial movement therewith through a part only of the path of

movement of said first element, joint movement of said elements being sufiicient to dispose said elements

on the opposite sides, respectively, of the vertical plane of said flange, said second element beingvertically spaced from said first element, spring means urging said elements to their vertical and

longitudinally spaced separation, pin means laterally extending from one of said elements and a cam slot

being formed in the other of said elements, said pin means being engageable in said cam slot, one of

said elements having a pivot pin extending laterally therefrom and the other element having a longitudinal

surface engageable by said pivot pin so that said arms are pivotally and longitudinally movable relative

one another with said pivotal and longitudinal movement being dependent on the configuration of said

cam slot, and means to move said pivot pin along said longitudinal surface against said spring means.

2. In a gripper mechanism for engaging a part flange, a guide means extending longitudinally toward the

flange, a carriage movable along said guide means and having a first terminal vertically faced flange

engaging element, means for actuating said carriage for movement along said guide means, a gripping

finger having a second terminal flange engaging element, pivot means for pivotally connecting said finger

to said carriage, said pivot means being longitudinally movable relative one of said finger and carriage,

cam means for directing relative longitu-v dinal and pivotal movement of said finger flange engaging

element, means on said guide means for engaging said finger as said carriage is moved along said guide

means so that said cam means is operable to cause said relative movement between said finger and said

carriage to first lower said finger means into gripping alignment with said carriage terminal and then bring

said elements toward each other in a flange gripping relation. 7

3. A gripper mechanism for a material handling device comprising guide means, a carriage longitudinally

movable along said guide means, a first vertically faced gripping element at one end of said carriage

positioned for substantially normal abutting engagement with a workpiece part flange in the longitudinal

path of said carriage, a member displaceably mounted on said carriage having a second gripping

element, connecting means between said member and said carriage accommodating both relative pivotal

and longitudinal movement therebetween,


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resilient means interposed between said member and carriage urging said member to one extreme of

pivotal and longitudinal movement wherein said gripping elements are both longitudinally and vertically

spaced, abutment means fixed relative to said guide means engageable by said member at an

intermediate position in the longitudinal travel of said carriage adapted to arrest the longitudinal

movement of said member during the subsequent longitudinal movement of said carriage, said

connecting means including cam means for inducing controlled pivotal movement of said member to bring

said gripping elements into opposed cooperating gripping relation during said subsequent longitudinal

travel of said carriage, and means for moving said carriage longitudinally along said guide means to

produce initially a conjoint longitudinal movement of said carriage and member, next a continued

longitudinal movement of said carriage and pivotal movement of said member, and finally a gripping

longitudinal movement of said carriage.

MATERIALS HANDLING WITH GRIPPER ARM.docx

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