US3719270A

US3719270A - Workpiece transfer device

Info

Publication number: US3719270A
Application number: US00132282A
Authority: US
Inventors: A Budris; L Carrieri
Original assignee: US Industries Inc
Current assignee: Hitachi Zosen Clearing Inc
Priority date: 1971-04-08
Filing date: 1971-04-08
Publication date: 1973-03-06
Anticipated expiration: 1990-03-06
Also published as: GB1347840A; JPS4862064A; IT951229B

Abstract

A transfer device for transferring a workpiece from one station to another in a line of presses utilizing a form of crank driven linkage mechanism which horizontally reciprocates a carriage between two extreme positions while carrying a workpiece. A lift frame on which the carriage reciprocates, raises the carriage and the workpiece at one of said positions and lowers the carriage and workpiece at the other of said positions to deposit the workpiece at the next station.

Description

United States Patent [191 Budris et al.

[ 51 March 6, 1973 WORKPIECE TRANSFER DEVICE [75] Inventors: Albert P. Budris, Oak Lawn; Louis F. Carrieri, La Grange Park, both of 111.

[73] Assignee: U.S. Industries, Inc., New York,

22 Filed: Aprils, 1971 21 Appl. No.: 132,282

[52] US. Cl. ..l98/219 [51 Int. Cl ..B65g 25/04 [58] Field of Search ..198/219, 19

[56] References Cited UNITED STATES PATENTS 3,481,450 12/1969 Umbricht ..l98/219 3,154,191 10/1964 Schmidt ..198/2l9 Primary Examiner-Richard E. Aegerter Attorney-Johnston, Root, OKeeffe, Keil, Thompson & Shurtleff 5 7 ABSTRACT A transfer device for transferring a workpiece from one station to another in a line of presses utilizing a form of crank driven linkage mechanism which horizontally reciprocates a carriage between two extreme positions while carrying a workpiece. A lift frame on which the carriage reciprocates, raises the carriage and the workpiece at one of said positions and lowers the carriage and workpiece at the other of said positions to deposit the workpiece at the next statron.

11 Claims, 12 Drawing Figures PATENTEU MAR 61975 DIRECTION LI F LO ER g RETU RN TRANsF ER LOADER omacnou T RANSFER LOWER .NLOADER INVENTORS.

ALBERT P. BUDRIS LOUIS F. CARRIERI ATT'YS PATENTEU R 61975 719,270

SHEET 20F 5 INVENTORS; ALBERT R BUDRIS LOUIS F. CARRIER! 4 N -w mm 6 E 8 m mm mmm ow vw 9 H mm mm ATT'YS PATEN FIG, 7

TEW 3,719,270

SHEET 30F 5 FIG. 8

INVENTOR$J ALBERT P. BUDRIS LOUIS F. CARRIER! ATT'YS PATENTEDHAR 61975 3' 719,270

SHEET 4 0F 5 FIG. IO

FIG. 9

INVENTORS: g A BERT F? BUDRIS LOUIS F. CARRIERI PATENTEU W 51973 SHEET 5 OF 5 FIG.|2

INVENTORS. ALBERT P. BUDRIS LOUIS F. CARRIERI. law/ 9M?? 1/ flag M 1 fl ATT'YS WORKPIECE TRANSFER DEVICE BACKGROUND OF THE INVENTION The invention relates in general to a transfer device for transferring workpieces between stations in a line of metal forming presses. It may also be used as a loader for placing a workpiece in a press or in a turnover device, as well as an unloader for removing from another press a workpiece which has been formed.

Transfer devices useful for this purpose have been known heretofore, but such prior art devices have had certain disadvantages either from the standpoint of being complex and expensive to manufacture or rather cumbersome and difficult to operate at relatively high speeds. In a line of presses the first press in the line usually is a double action press where the workpiece is initially formed. It is also usual, but not always necessary, that the partially formed workpiece be removed from the double action press and delivered to a turnover device which reverses the position of the workpiece before it is transferred to the single action press. The remaining presses in the line are normally single action presses and the transfer device is utilized to remove the workpiece from the press and to advance it to succeeding stations between adjacent presses, and then to place it in the next succeeding press for the following operation.

To illustrate examples of some of the prior art structures, reference is made to the Bannon U.S. Pat. No. 3,233,751 wherein a carriage is provided with grippers or jaws at each end thereof. In this arrangement the carriage is elevated after the jaws grip the workpiece and is then moved to the next station where the jaws release the workpiece. The jaws at one end of the carriage member remove a workpiece from one press and the jaws at the other end of the carriage member deposit the workpiece in the next succeeding press. One problem with this arrangement, however, is that the entire mechanism is raised and lowered as well as being reciprocated longitudinally, which requires considerably weight to be moved, and a problem of inertia in starting and stopping the mechanism is encountered.

The U.S. Pat. to Young, No. 3,890,043 utilizes a movable frame member which merely moves up and down, and has a carriage which moves up and down with the frame but also reciprocates horizontally with respect to the frame. The carriage there is provided with rails which will support a workpiece as it is transferred between stations, and is also provided with grippers or jaws at each end thereof which are used to grip the workpiece and lift it out of the die in one press and deposit it in the die in the next succeeding press. Again, however, the operating mechanism is rather complex and thus expensive to manufacture and maintain.

Other prior art patents relating to this same general subject matter include, for example, the I-lallahan U.S. Pat. No. 2,836,280, and the Danly U.S. Pat. No. 3,199,439.

SUMMARY OF THE INVENTION The invention incorporates a lift frame which is raised and lowered by cam means. A carriage is mounted on the lift frame for longitudinal reciprocating movem n and is guided in such movement by guide rails. A linkage arrangement operated by crank means is utilized for imparting the reciprocating movement to the carriage. The carriage is provided with guide means in the form of a vertically positioned slotted member in which one end of the link is located. Longitudinal reciprocating movement of the carriage is caused by a similar movement of the end of the link confined within the slot. The slot enables the carriage to be raised and lowered with the lift frame during which time the end of the link will traverse such slot. The linkage is driven by means of a crank fixed to a pinion which is caused to rotate by meshing with an oscillating gear segment. Movement of the gear segment in one direction will rotate the pinion in mesh therewith as well as the crank thereon, and move the end of the link together with the carriage from one extreme position to the other. Restraining means are provided for the ends of the link to insure proper operation thereof.

OBJECTS OF THE INVENTION The present invention is designed as an improvement over the mechanisms of this type heretofore known, and it is, therefore, one of the primary objects of the present invention to provide a relatively simple and economical mechanism for transferring a workpiece between presses or between stations in a line of presses.

A further object of the invention is to provide a simplified workpiece transfer device wherein a novel link age arrangement is utilized as the drive mechanism for reciprocating the carriage supporting the workpiece between two extreme positions.

Another object of the invention is to provide a transfer device wherein a carriage supporting a workpiece is reciprocated on a lift frame by a novel linkage arrangement driven by a crank.

A still further and more specific object of the invention is to provide a novel drive means for the reciprocating carriage of a workpiece transfer device which includes a linkage arrangement actuated by a crank means driven by cooperating pinion and gear segment means.

A still further and specific object of the invention is to provide a novel drive means for the reciprocating carriage of a workpiece transfer device, which utilizes a linkage arrangement and wherein the carriage is supported on a lift frame which raises and lowers the carriage therewith, and wherein the lift frame moves with respect to the linkage arrangement.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a somewhat diagrammatic illustration in plan of a transfer device embodying the present invention;

FIG. 2 is a diagrammatic illustration in elevation showing the transfer device of the present invention being used as a loader for one press and as an unloader for another press, and illustrating the path of movement of the workpiece as it is being transferred;

FIG. 3 is a transverse vertical sectional view of the device of the present invention taken substantially along the plane of line 3-3 of FIG. 1;

FIG. 4 is a longitudinal view partly in section and partly in elevation of the device embodying the present invention taken along the plane of line 4-4 of FIGS. 1 and 3;

FIG. 5 is a transverse vertical sectional view through the device with the carriage in the lower position as shown in FIG. 4 but with the linkage arrangement in the position illustrated in FIG. 7 where the bottom of the linkage is in its lowermost position;

FIG. 6 is a view similar to FIG. 4 but showing the positions of the linkage arrangement and drive means therefor about one-fourth of the way through the cycle in moving the carriage from one extreme position to the other and with the carriage in its raised position;

FIG. 7 is a view similar to FIG. 6 but showing the positions of the same parts half way through the cycle of moving the carriage from one extreme position to the other;

FIG. 8 is a view similar to FIGS. 4, 6 and 7 but showing the positions of the same parts when the carriage has reached the opposite extreme position and has been lowered;

FIG. 9 is a longitudinal sectional view partly in elevation showing the lift frame and the means for actuating it and taken substantially along the plane of line 9-9 of 20 FIGS. 1 and 3, and showing the lift frame in its lower position;

FIG. 10 is a fragmentary vertical transverse sectional view taken substantially along the plane l 10 of FIG. 9;

FIG. 1 1 is a view similar to FIG. 9 but showing the lift frame in its upper position; and

FIG. 12 is a somewhat diagrammatic illustration in side elevation showing the manner in which a workpiece may be moved through successive stations and from one single action press to the next.

DETAILED DESCRIPTION Referring now more particularly to the drawings, and especially to FIGS. 1 and 2, the transfer device of the present invention comprises an outer stationary frame 1, an inner stationary frame 2, and an intermediate movable or lift frame 3. A carriage 4 is mounted for longitudinal reciprocating movement on suitable guide bars mounted along the upper part of the lift frame and the manner of raising and lowering the lift frame and reciprocating the carriage will be described in greater detail hereinafter.

As mentioned heretofore, the transfer device may be used either as a loader or an unloader, and in FIG. 1 it is illustrated as an unloader whereby, when the carriage is at the left side of the frame it will be actuated to lift a workpiece from the press 5 and then carry it toward the right to another station.

The device is preferably driven by a direct connection to the drive of the press itself which is adjacent thereto so that the carriage will be actuated in synchronized timed relation with the operation of the press. To this end a gear box 6 is provided with suitable connections to the press drive, and from which extends a shaft on which is mounted a drive pinion 7. This pinion meshes with a gear 8 on a shaft 9 which also has mounted thereon the lift cam 10 and the transfer cam 11. As will be seen hereinafter, the lift cam is actuated to raise and lower the lift frame 3 and the transfer cam 11 is operable to actuate the drive mechanism which reciprocates the carriage. A cam follower 12 is maintained in contact with the contoured edge of lift cam 10, and a cam follower 13 is maintained in contact with the transfer cam 1 l.

In FIG. 2 the stationary frame 1 of the transfer device when used as an unloader is shown as being on the right side of the press 5. In this position the press 5 would normally be a single action press and the last press in the line from which the workpiece will be unloaded and transferred to a final station where it will be removed and either have further operations performed thereon, or may be packed for shipment.

As mentioned above, the first press in a press line is normally a double action press. The stamped or formed workpiece may be removed from such press by using the transfer device as an unloader and placing the workpiece in a turnover device. From the turnover device the workpiece, after being reversed, may then be removed, whereupon the device may be used as a loader as shown in FIG. 2 to place the partially formed workpiece in the first single action press in the line which may be indicated by the numeral 5a.

As will be noted, it is assumed that in FIG. 2 the workpiece advances toward the right, and the motion of the carriage supporting the workpiece is as illustrated therein where the carriage is in its upper position as it moves toward the right and in the lower position as it returns toward the left.

Reference will now be made particularly to FIGS. 3 through 8. FIG. 4 shows the transfer cam l l on its shaft 9 and shows the cam follower 13 bearing against the contoured edge thereof. As will be described more specifically hereinafter, the rotation of the cam will impart a reciprocating movement to the carriage 4. The carriage may be provided with any suitable guide means, but in FIGS. 4 and 5 these have been illustrated as a guide bar 14 extending longitudinally of the carriage and mounted on the lift frame 3 by means of a bracket 15. Upper and lower pairs of spaced apart rollers 16 and 17 are provided at one side of the carriage and are mounted on suitable pins in the apron 17a extending downwardly at one side of the carriage. These rollers 16 and 17 contact the upper and lower sides of the rail 14 and the carriage is guided thereby.

At the opposite side of the carriage a different type of guide means is preferably provided which comprises the rod 18, also mounted on the lift frame 3, and which has a tubular guide member 19 with ball bearings therein which receives the rod 18. Thus, as the carriage is reciprocated the guide bar 14 and the rod 18 at opposite sides of the carriage will guide it in this movement.

At the center of the carriage and extending downwardly therefrom is a slotted member 20 which has a vertically extending slot 21 therein. A link 22 has a roller 23 at one end thereof (FIG. 5) which is mounted on a pin 24 passing through the end of the link 22. When thelink 22 is actuated to move the roller 23 in a horizontal direction it will cause movement of the carriage due to its confinement within the slot of the member 20.

Also mounted on the pin 24 at opposite ends thereof are

rollers

25 and 26. The purpose of these rollers will become evident presently, and it may be stated briefly here that they cooperate with restraining means adjacent the extreme positions of the carriage for proper operation of the device.

The link 22 is elongated and at substantially the mid point along the length thereof a stub shaft 27 passes therethrough. This shaft extends through the link and beyond the sides thereof to support one end of a crank member generally indicated at 28, and which consists of the spaced

side members

29 and 30. The other end of the crank 28 is mounted for rotation about an axis which consists of the stub shafts 31 and 32. The side 29 of the crank is connected to the inner end of shaft 31 and the opposite side 30 is connected to the inner end of the other shaft 32, as may be more clearly seen in FIG. 5. A pinion 33 is also secured on the stub shaft 32, and it will be evident that rotation of such pinion, together with its shaft, will cause a rotation of the crank 28. The pinion 33 is caused to rotate by being in mesh with a gear segment 34 mounted for pivotal movement about the pivot pin 35. The cam follower 13 is mounted on a bracket 36 secured to the gear segment 34 so that as the transfer cam 11 rotates and the follower l3 follows the contour thereof, an oscillating motion will be imparted to the gear segment 34.

The lower end of the gear segment 34 extends beyond the pivot point 35 and has secured thereto the outer end of a piston rod 37. The inner end of this rod has a piston thereon and is adapted to reciprocate within the cylinder 38. Suitable fluid pressure within the cylinder creates a pull on the lower end of gear segment 34, thereby urging the cam follower 13 into engagement with the edge of the cam 1 1.

As the cam 11 rotates in a clockwise direction, as viewed in the various figures of the drawings, it will cause the gear segment 34 to move from its one extreme position shown in FIG. 4, to its opposite extreme position shown in FIG. 8, and in so doing will move through the intermediate positions illustrated, for example, in FIGS. 6 and 7. As the gear segment 34 moves from the position shown in FIG. 4 to the position shown in F IG. 8, the pinion 33 will rotate the crank 28 through approximately 180, and in so doing will move the roller 23 on the end of link 22 from one end of the inner stationary frame to the other, and by reason of its association with slot 21 it will likewise cause a similar movement to be imparted to the carriage 4.

It is necessary that the outer ends of the link 22 be restrained at all times in order properly to control the movement of the'link. To this end a plurality of U- shaped guide members are provided, the pairs of

guide members

39 and 40 being horizontally positioned at each end of the inner stationary frame 2 and the guide member 41 being vertically positioned near the bottom of said frame.

It will be noted in FIG. 4, where the carriage is illustrated as being in one of its extreme positions, that the

rollers

25 and 26 are received within the pair of U- shaped guide members 39. In the absence of such control, the end of the link might drop downwardly in the slot 21 and would fail to perform its function properly.

In FIG. 6 it will be noted that the crank 28 has been rotated through approximately 45 degrees and the

rollers

25 and 26 about it leave the confines of the slot in the guide members 39. The opposite end of the link, however, is provided with a similar roller 42, which at this point is entering the vertical slot in the guide member 41. Continued movement of the crank in a counterclockwise direction will move the various parts to their intermediate positions shown in FIG. 7 where the roller 42 on link 22 is near the bottom of the slot in the guide member 41. Continued rotation of the crank in a counterclockwise direction will move the upper end of the link and the rollers thereon toward the right and by the time the roller 42 moves upwardly and leaves the slot in its guide member the

rollers

25 and 26 will have entered the slots in the guide members 40. Thus, at all times the link is being guided and restrained at one or the other ends thereof.

It is evident, of course, that the carriage will have a vertical component of movement, and the slot 21 in the member 20 will permit the carriage to be elevated as shown in FIGS. 6 and 7, whereupon the member 20 will move upwardly and the roller 23 will traverse the slot 21.

The mechanism for raising and lowering the lift frame 3 is illustrated more clearly in FIGS. 9, l0 and 11. The lift cam 10 is shown as mounted on the cam shaft 9 and has the cam follower 12 in contact therewith. The lift frame is moved through the operation of two pairs of bell crank levers, one of which is mounted at one side of the inner stationary frame 2 and the outer stationary frame 1. These are connected together by a link. A stub shaft 43 is mounted at one side of the inner stationary frame and the bell crank lever 44 is mounted thereon and secured thereto for rotation therewith. The bell crank lever is provided with two

arms

45 and 46. The end of arm 46 is provided with a pivot 47 on which is mounted one end of a leg 48 connected to the lift frame 3 in such a way that a counterclockwise rotation of the bell crank lever 44 will raise the leg 48 and the lift frame as well as the carriage 4 mounted thereon.

The arm 45 of the bell crank lever is connected to one end of a link 49 by means of a pivot pin 50. The other end of link 49 is connected at 51 to one leg 52 of a second bell crank lever which is pivotally mounted to the inner stationary frame at 53. The other arm 54 of the bell crank is pivotally connected to a leg 55 by means such as the pivot pin 56. The leg 55 is likewise connected to the lift frame and cooperates with the leg 48 to raise and lower the frame.

A pinion 57 is mounted on the shaft 43 and is secured thereto so that rotation of the pinion will rotate the shaft and bell crank levers by reason of the connecting link 49.

The cam follower 12 is mounted on a gear segment 58 rotatably mounted on a pin or stub shaft 59 on the inner stationary frame. The gear segment 58 is in mesh with the pinion 57 so that oscillation or rotation of the gear segment will likewise rotate the pinion 57.

FIG. 9 shows the lift frame on which the carriage is mounted in the lowered position thereof. As viewed in FIGS. 9 and 10, the shaft 9 and cam 10 will rotate in a clockwise direction. It will be noted that as the cam 10 rotates from its position in FIG. 9 the high part of the cam will bear against the cam follower 12 and rotate the gear segment 58 in a clockwise direction. This will cause a counterclockwise rotation of the pinion 57 and the two bell crank levers so that the

arms

46 and 54 thereof will raise the

legs

48 and 55 and thereby elevate the lift frame and the carriage to the position shown in FIG. 11.

It will be evident that the transfer cam 1 1 and the lift cam 10 are so designed as to cause the lift frame and carriage to be raised when the carriage is in one of its extreme positions and to be lowered when the carriage reaches its other extreme position.

The carriage for transferring the workpiece will normally be provided with elongated support rails such as those indicated by the numeral 60 in FIGS. 4 and 5 with one such rail positioned at each side of the carriage. Each rail is provided with a nest consisting of the shoes 61. These may vary with the shape and size of the piece part being transferred, but, in general, they support the part between them and the part nests therein to prevent longitudinal movement thereof.

A pair of stationary rails 62 is positioned above the carriage and outwardly of the movable rails 60. These stationary rails also are provided with similar nests 63 spaced apart along the length thereof in the manner shown in FIG. 4.

In transferring a workpiece from one station to another, the workpiece will be resting upon the stationary rails 62 within a nest. It will have been placed there from the press either by movable rails such as those indicated at 60 or by jaws or grippers which will have gripped the piece in the press and lifted it therefrom. If the transfer device is being utilized as an unloader, as in FIG. 1, the carriage will be in its lower position as shown in FIG. 4 but in the extreme position thereof away from the press. In this situation the carriage will remain in its lower position during its return travel to the press in accordance with the diagrammatic showing of the carriage movement for the unloader in FIG. 2.

When it reaches the other extreme position it will be elevated with the lift frame by action of the lift cam. If there is a workpiece on the stationary rails, the rails on the carriage will pick it up as the carriage is elevated and it will then be transferred to the next station as the carriage moves to its other extreme position. When it reaches that point the carriage is lowered and as it moves downwardly through the stationary rails 62 the work piece will be deposited thereon at the next station.

It is customary to utilize grippers or jaws to grasp the workpiece and lift it out of the die in one press and other jaws to grip the workpiece at another station and deposit it in the die area of the next press. In order that the presses may be located sufficiently far apart in the press line there will normally be several stations between adjacent presses. FIG. 12 illustrates somewhat diagrammatically a transfer device wherein jaws 64 are mounted at one end of the carriage and will grip the workpiece so that when the carriage is elevated the workpiece will likewise be elevated off of the die and be ready to be removed from the machine.

FIG. 12 also illustrates the adaptability of the present drive system for use either as a loader or unloader, or as a device for transferring workpieces between stations from one press to another. In FIG. 12, for example, the numeral 1 identifies the outer stationary frame of the transfer device which has been described above. For use between adjacent presses the frame may be lengthened as much as is necessary by the addition of a length thereto as shown at 1a. The internal mechanism within the frame 1 will remain the same, but the invention adapts itself so that the guide rails 14 and 18 may be elongated to extend above and beyond the additional portion 1a. Likewise, the stationary support rails 62 may be elongated as much as may be necessary to provide the desired number of stations between the presses.

In devices heretofore known, it would have been necessary to make the carriage 4 longer, but by the use of the present invention the same result can be obtained by the addition of a second carriage which may be identified as 4a. The movable support rails 60 will then extend across the two carriages as shown in FIG. 12, and the secondary carriage 4a will have another set of jaws 65 mounted thereon. The presses are diagrammatically illustrated and are identified as 66 and 67, each having a die 68 and 69 thereon. The workpiece in the die 68 is identified by the letter W.

There are three intermediate stations between the

presses

66 and 67, and the workpieces thereon are identified as W1, W2 and W3. The workpiece within the press 67 is indicated at W4.

When the carriages are raised the jaws 64 will raise the workpiece W out of the die and at the same time carriage 4 will pick up workpiece W1 and carriage 4a will pick up workpiece W2. The jaws 65 will pick up workpiece W3, and at the same time workpiece W4 in the press 67 will have been grasped by similar jaws mounted on the transfer device between press 67 and the next succeeding press. On the other hand, W4 could be picked up by the unloader of FIG. 2 if it happens to be the last press in the line.

In the uppermost position of the carriages it will move toward the right as indicated by the dot dash lines with arrows in FIG. 12 to the opposite extreme position of the carriage. The lift cam at this point will then have reached the place on its contour where the lift frame will lower, whereupon each workpiece will be deposited at the next succeeding station on the stationary rails 62.

The arrangement disclosed herein lends itself to diversification and enables it to be used as a loader or an unloader, or as an elongated transfer device between adjacent presses. The drive means is relatively simple and uncomplicated compared to mechanisms in the prior art which have been used in an attempt to accomplish the same purpose.

Changes may be made in the form, construction and arrangement of parts from those disclosed herein without in any way departing from the spirit of the invention or sacrificing any of the attendant advantages thereof, provided, however, that such changes fall within the scope of the claims appended hereto.

The invention is hereby claimed as follows:

1. A transfer device for transferring a workpiece between stations in a line of metal forming presses comprising,

a. a lift frame member mounted for movement between raised and lowered positions,

b. a carriage adapted to carry a workpiece and mounted on said lift frame for movement therewith between the raised and lowered positions thereof, and with respect thereto in a substantially horizontal plane between two extreme positions,

c. a link having at one end thereof a sliding connection with said carriage permitting the raising and lowering of said lift frame and carriage with respect to said one end of said link,

d. means including a crank connected at one end thereof to said link and mounted at the other end thereof on supporting pins for rotation about an axis substantially midway between said two extreme positions of said carriage thereby to reciprocate said carriage, and

e. means to raise said lift frame and the carriage thereon while said carriage is in one of said extreme positions, and to lower said lift frame and carriage while said carriage is in the other of said extreme positions.

2. A transfer device as defined in claim 1, and means to rotate said crank including a pinion on said axis connected to said crank, a toothed member meshing with said pinion, and means to actuate said toothed member to rotate said pinion.

3. A transfer device as defined in claim 2, wherein said toothed member is a gear segment, and said means to actuate said toothed member includes a cam and a cam follower on said gear segment.

4. A transfer device as defined in claim 1, wherein the elements defined in paragraph (e) thereof includes a plurality of bell crank levers, a leg connected to one arm of each of said levers and to said lift frame, whereby rotation of said levers in one direction will raise said lift frame and rotation thereof in the other direction will lower said lift frame, and means to rotate said levers.

5. A transfer device for transferring a workpiece between stations in a line of metal forming presses comprising,

a. a stationary outer frame,

b. a stationary inner frame,

c. a movable lift frame between said inner and outer frames,

d. means for raising and lowering said lift frame,

e. a carriage mounted on said lift frame and movable therewith to the raised and lowered positions thereof and with respect thereto in a horizontal reciprocating motion, and adapted to carry a workpiece therewith,

f. means for reciprocating said carriage on said lift frame between two extreme positions including 1. a link connected at one end to said carriage,

2. crank means pivotally secured at one end to said link and mounted for rotation at the other end on said inner frame,

g. means for rotating said crank and imparting to said one end of said link and to the carriage to which it is connected a reciprocating movement relative to said lift frame, and

h. restraining means cooperating with said link to guide said one end thereof in a horizontal path during reciprocation of said carriage.

6. A transfer device as defined in claim 5, wherein said restraining means includes slotted members mounted on said inner frame and rollers on said link adapted to be received by said slotted members during movement of said carriage.

7. A transfer device as defined in claim 5, wherein said restraining means includes a slotted member on said inner frame adjacent each extreme position of said carriage and rollers on said one end of said link adapted to be received in said slots as the carriage approaches each of its extreme positions.

8. A transfer device as defined in claim 5, wherein said restraining means includes a slotted member adjacent each extreme position of said carriage, rollers on said one end of said link adapted to be received in said slots as the carriage approaches each of its extreme positions, a slotted member intermediate the two extreme positions of said carriage, and a roller on the other end of said link adapted to be received in said last named slotted member as said carriage moves through intermediate positions between the two extreme positions thereof.

9. A transfer device for transferring a workpiece between stations in a line of metal forming presses comprising,

d. means to move said one end of said link in a generally horizontal direction thereby to reciprocate said carriage,

e. means to raise said lift frame and the carriage thereon while said carriage is in one of said extreme positions, and to lower said lift frame and carriage while said carriage is in the other of said extreme positions, and

f. restraining means cooperating with said link to control the movement thereof and guide said one end thereof in a horizontal path of movement during reciprocation of said carriage, including rigidly mounted slotted members, and rollers on said link adapted to be received by said slotted members.

10. A transfer device for transferring a workpiece between stations in a line of metal forming presses comprising,

0. a link having at one end thereof a sliding connection with said carriage permitting the raising and lowering of said lift frame and carriage with respect to said one end of said link,

e. a plurality of bell crank levers, a leg connected to one arm of each of said levers and to said lift frame, whereby rotation of said levers in one direction while said carriage is in one of said extreme positions will raise said lift frame and rotation thereof in the other direction while said carriage is in the other of said extreme positions will lower said lift frame, and

f. means to rotate said levers, including a pinion on the axis of rotation of one of said levers, a toothed member in mesh with said pinion, and means to actuate said toothed member to rotate said pinion.

11. A transfer device as defined in claim 10, wherein said toothed member is a gear segment, and said means to actuate said toothed member is a cam, and a cam follower on said gear segment.

Claims

1. A transfer device for transferring a workpiece between stations in a line of metal forming presses comprising, a. a lift frame member mounted for movement between raised and lowered positions, b. a carriage adapted to carry a workpiece and mounted on said lift frame for movement therewith between the raised and lowered positions thereof, and with respect thereto in a substantially horizontal plane between two extreme positions, c. a link having at one end thereof a sliding connection with said carriage permitting the raising and lowering of said lift frame and carriage with respect to said one end of said link, d. means including a crank connected at one end thereof to said link and mounted at the other end thereof on supporting pins for rotation about an axis substantially midway between said two extreme positions of said carriage thereby to reciprocate said carriage, and e. means to raise said lift frame and the carriage thereon while said carriage is in one of said extreme positions, and to lower said lift frame and carriage while said carriage is in the other of said extreme positions.

1. a link connected at one end to said carriage,

2. crank means pivotally secured at one end to said link and mounted for rotation at the other end on said inner frame, g. means for rotating said crank and imparting to said one end of said link and to the carriage to which it is connected a reciprocating movement relative to said lift frame, and h. restraining means cooperating with said link to guide said one end thereof in a horizontal path during reciprocation of said carriage.

5. A transfer device for transferring a workpiece between stations in a line of metal forming presses comprising, a. a stationary outer frame, b. a stationary inner frame, c. a movable lift frame between said inner and outer frames, d. means for raising and lowering said lift frame, e. a carriage mounted on said lift frame and movable therewith to the raised and lowered positions thereof and with respect thereto in a horizontal reciprocating motion, and adapted to carry a workpiece therewith, f. means for reciprocating said carriage on said lift frame between two extreme positions including

9. A transfer device for transferring a workpiece between stations in a line of metal forming presses comprising, a. a lift frame member mounted for movement between raised and lowered positions, b. a carriage adapted to carry a workpiece and mounted on said lift frame for movement therewith between the raised and lowered positions thereof, and with respect thereto in a substantially horizontal plane between two extreme positions, c. a link having at one end thereof a sliding connection with said carriage permitting the raising and lowering of said lift frame and carriage with respect to said one end of said link, d. means to move said one end of said link in a generally horizontal direction thereby to reciprocate said carriage, e. means to raise said lift frame and the carriage thereon while said carriage is in one of said extreme positions, and to lower said lift frame and carriage while said carriage is in the other of said extreme positions, and f. restraining means cooperating with said link to control the movement thereof and guide said one end thereof in a horizontal path of movement during reciProcation of said carriage, including rigidly mounted slotted members, and rollers on said link adapted to be received by said slotted members.

10. A transfer device for transferring a workpiece between stations in a line of metal forming presses comprising, a. a lift frame member mounted for movement between raised and lowered positions, b. a carriage adapted to carry a workpiece and mounted on said lift frame for movement therewith between the raised and lowered positions thereof, and with respect thereto in a substantially horizontal plane between two extreme positions, c. a link having at one end thereof a sliding connection with said carriage permitting the raising and lowering of said lift frame and carriage with respect to said one end of said link, d. means to move said one end of said link in a generally horizontal direction thereby to reciprocate said carriage, e. a plurality of bell crank levers, a leg connected to one arm of each of said levers and to said lift frame, whereby rotation of said levers in one direction while said carriage is in one of said extreme positions will raise said lift frame and rotation thereof in the other direction while said carriage is in the other of said extreme positions will lower said lift frame, and f. means to rotate said levers, including a pinion on the axis of rotation of one of said levers, a toothed member in mesh with said pinion, and means to actuate said toothed member to rotate said pinion.