United States Patent  Inventors Erwin B. Byam Wolcott; Gregory L. Klein, Cheshire, both of Conn.  Appl. No. 885,835  Filed Dec. 17, 1969  Patented Jan. 11, 1972  Assignee Textron, Inc.
 TRANSFER MECHANISM 13 Claims, 8 Drawing Figs.
 11.8. C1 2l4/1 BC, 72/422, 214/1 Q  lnt.Cl 321d 43/10  Field of Search 21411 BC, 1 BD, 1 Q; 72/422  References Cited UNITED STATES PATENTS 3,120,770 2/1964 Hoyt 214/1 B4X Primary ExaminerGerald M. Forlenza Assistant Examiner-George F. Abraham Attorney- Delio and Montgomery ABSTRACT: A transfer mechanism capable of transferring and rotating workpieces from one die station to another in a header or similar apparatus, comprising first lever means pivotally mounted to the frame of the machine and bracket means pivotally connected to the first lever means. Sliding and rotating means having finger means thereon, are mounted on the bracket means. Pivotal means act on said sliding and rotating means to raise and lower the finger means to open and closed positions, respectively. First and second drive means are provided to reciprocate the bracket means and actuate the pivotal means in timed relationship to the bracket means.
PATENTED mu 1 1972 SHEET 1 [1F 3 lrllr (5mm 8. Bwam mm m K W w Z me 6D m PATENTED JAM 1 1972 saw 3 OF 3 INVENTORS mn iwm BK A ELM mw w mwqw amf 6 e D M TRANSFER MECHANISM This invention relates to a transfer mechanism for a variety of part-forming machines or headers and, more particularly, to means for transferring a workpiece from one die station to another in machines having a plurality of stations.
The present transfer mechanism may be employed either in a multistation machine where a number of tools operate successively upon the workpiece, or in a two-station machine where the workpiece is conveyed from a first to a second die station.
In headers and in many part-forming machines, it is necessary to have a transfer mechanism convey the workpiece from one station to the next so as to accurately center the workpiece on the die at the station to which it is transferred. It is desirable that the workpiece be correctly positioned axially at the die station to prevent breakage or undue wear of the tools. In some applications, it is desirable that the workpiece be rotated or turned through an angle of 180 between die stations.
In prior art machines in which rotation of the workpiece is accomplished, the finger means for gripping the workpiece are usually tilted or raised, so that thereis sufficient clearance when the finger means are rotated. In the case where the finger means are tilted, as substantially large number of parts have to be placed on a single movable frame member which is moved in coordination with the other operations of the machine.
In most transfer mechanisms, once the workpiece is transferred to the next adjacent station, the finger means must open to release the workpiece so that it may be positioned in the die. This is accomplished by raising the finger means out of position so that the work-forming punch may act on the workpiece without smashing the finger means.
In the past, finger means constructed from intricate parts were used. These finger means had the singular disadvantage in that they could not be locked in an open raised position. As a result, constant pressure had to be applied by appropriate connecting means to maintain the finger means open against the force of biasing springs which acted to close the finger means. Further, intricate linkage means acted on the connecting means to maintain the finger means in a raised open position during the return of the finger means to their initial die station. As a result, part of the linkage means had to travel between two positions in order to maintain the finger means in a raised open position.
Accordingly, it is an object of this invention to provide a new and improved transfer mechanism having finger means which can be maintained in a raised locked position without the use of expensive linkage means.
Another object of the invention is to provide a new and improved transfer mechanism having simple pivotal means for moving the finger means to an open or closed position.
A further object of the invention is to provide a new and improved transfer mechanism having rotating means to rotate the workpiece while it is being transferred from one die station to another, wherein the finger means describe an arcuate path away from the face of the die as it moves from one die station to another.
Still another object of the invention is to provide a new and improved transfer mechanism having rack means which are engaged by gear means connected to the finger means, such that the rack means and the gear means remain in constant contact.
Yet a further object of the invention is to provide a new and improved transfer mechanism which is mounted on a movable frame member so that the transfer mechanism can be positioned for small or large workpieces.
Still other objects and advantages of the invention will in part be obvious and will in part appear from the specification.
In accordance with the above objects, the transfer mechanism of this invention for a header finger similar apparatus comprises first lever means pivotally connected to the frame of the apparatus. Bracket means for supporting the positioning means are pivotally mounted on the first lever means. First drive means act upon the bracket means to reciprocate the bracket means along an arcuate path. Rotating and sliding means having finger means thereon are mounted on the bracket means. Pivotal means engaged by second cam drive means act upon the rotating and sliding means to raise or lower the finger means to an open or closed position. Rack means are connected to the first lever means, such that the first lever means can slide with respect to the rack means. Upon reciprocation of the bracket means, the rack means move only in a direction essentially perpendicular to its longitudinal axis so as to remain in constant contact with a rotating gear on the rotating and sliding means. The finger means comprise two finger members pivotally mounted on the rotating and sliding means. The finger members are spring biased at one end so that their free ends are forced toward each other for gripping a workpiece. The rotating and sliding means comprise a first hollow shaft slidably mounted on a central shaft having detent surfaces at its lower end, so that when the hollow shaft is in a raised position protruding portions on the finger members pass into the detent surfaces to lock the first hollow shaft in a raised position.
The invention accordingly comprises the features of construction, combination of elements and arrangement of parts which will be exemplified in the construction hereinafter set forth and the scope of the invention will be indicated in the claims.
For a fuller understanding of the nature and objects of the invention, reference is had to the following description taken in connection with the accompanying drawings, in which FIG. 1 is a front view of the transfer mechanism;
FIG. 2 is a partial top view of the transfer mechanism;
FIG. 3 is a sectional view taken along line 3-3 of FIG. 2;
FIG. 4 is a sectional view taken along line 4-4 of FIG. 3;
FIG. 5 is a sectional view taken along line 5-5 of FIG. 1;
FIG. 6 is a sectional view taken along line 6-6 of FIG. 5;
FIG. 7 is a side view similar to FIG. 6; and
FIG. 8 is a sectional view taken along line 8-8 of FIG. 7.
Referring to FIGS. l-4, the transfer mechanism of this invention is shown mounted on a header or like apparatus. A main drive shaft 10 has cam plates 12 and 14 thereon which act on followers 16 and 18 to pivot a lever member 20 pivotally mounted at 22 to the frame 24 of the apparatus. The lever 20 reciprocates a rod 26 which is pivotally connected to the lever 20 through pivotal link 28. The rod 26 reciprocates a bracket support member 30 through pivotal connection 31. The drive shaft 10 also drives a shaft 32 through bevel gear connection 33. Shaft 32 is connected to cam shaft 34 by means of a flexible coupling 35 so as to continually rotate cam plates 36 mounted thereon. The flexible coupling 35 permits shaft 34 to move in a direction transverse to its longitudinal axis with respect to shaft 32 for reasons that will be explained below. A cam plate is provided for each work station and workpiece positioning means are supported on bracket member 30. The cam plates 36 are positioned on rod 34 by support plates 38. The cam plates 36 engage the pivotal means shown in detail in FIG. 5, which will be explained in detail below.
In FIGS. 2-5, the bracket member 30 is shown pivotally connected to lever members 40 by means of pins 42 which levers, in turn, are pivotally connected to the movable frame member 43 by means of pins 44. The movable frame member 43 is supported on stationary frame member 24 by bolts 43a passing through slots 43b. In this manner, the frame member 43 may be positioned so that the transfer mechanism supported thereon can accommodate the transfer and rotation of either large or small workpieces from one die station to the next.
During the reciprocation of bracket member 30, the travel of levers 40 is limited by stops 46 so as to correctly position the bracket member 30 in its terminal positions. The reciprocation of the bracket member 30 connected to levers 40 which are pivotally connected to the frame 24, will cause the bracket member 30 to describe an arcuate path during its movement, as shown by the arrows 48. It can also be appreciated that the radius of the arcuate path will depend on the length of the levers 40. The bracket member 30 has a plurality of contoured. surfaces 50 for supporting members 52 by means of clamps 54, as seen in FIGS. 6 and 7. The members 52 support therein a central stationary shaft 56, about which is slidably mounted a hollow shaft 58. The position of the support member 52 as well as the shafts mounted thereon, can be adjusted vertically by loosening clamps 54 and adjusting a threaded bolt 60. The hollow shaft 58 is maintained in position by bearing surfaces 62 so that it can slide against their surfaces. The bearing surfaces 62 and roller bearings 64 are positioned to permit the hollow shaft to rotate with a minimum of friction. The hollow shaft 58 rests on support member 52 by means of nut members 66 threadably engaging the end of shaft 58. The nut members 66 rest on washer 68 which, in turn, rests on a bearing surface 70. The bearing surface 70 slides on rollers 72 which, in turn, can slide on bearing surface 74 The bearing surface 74 is supported on a sleeve 76 which rests on roller bearings 64. As a result of this arrangement, when the hollow shaft 58 is rotated (in the position shown in FIG. 6), the washer 68 will rotate with the shaft 58 with a minimum of friction. A sleeve 78 is positioned adjacent the upper portion of the hollow shaft 58. A gear 80 is mounted on the sleeve 78 by means of bolts 82. The sleeve 78 and central shaft 56 are maintained in a stationary position relative to each other by means of an elongated pin 84. The pin 84 also passes through longitudinal slots 86 in shaft 58 so that the shaft 58 can move along its longitudinal axis relative to gear 80 and central shaft 56. However, the presence of pin 84 in slots 86 causes the shafts 56 and 58 to rotate in unison with gear 80. The lower end of the shaft 58 is formed with an extending flange section 88 and enlarged supporting sections 89 on which are pivotally mounted finger members 90. Protruding roller members 92 are mounted at the lower end of finger members 90. Gripping members 93 are located on the external side of the finger members 90 by means of pins 94, so that they can grip the workpiece. Adjusting threaded members 96 are positioned on the gripping members 93 so that the position of the gripping members relative to finger members 90 can be adjusted. Extending members 98 are attached to the upper end of finger members by means of a bolt 100. The members 98 are acted on by springs 102 seated in openings 104. Biasing springs 102 act on extending members 98 to force the gripping members 93 sufficiently close to each other to grip a workpiece. Spring metal strips 106 are also attached to the finger members 90 by means of bolts 100 so that the strips can maintain pins 94 in place during the normal operation of the apparatus. However, if the apparatus should malfunction so that the punch strikes the gripping members 93, the members 93 will be torn loose from finger members 90 and damage to the rest of the apparatus will be avoided.
When the lifting means, shown in FIG. 5, acts on the flange 88 to raise the hollow shaft 58, the lower end of the stationary central shaft 56 will force finger members 90 apart to an open position. The rollers 92 permit the finger members to slide over the shaft 56 with a minimum of friction. When the shaft 58 has been raised to the position shown in FIG. 7, rollers 92 pass into the detent surfaces 108 in the central shaft 56. The force of the springs 102 acting on the finger members 90, is sufiicient to lock hollow shaft 58in the raised position with no other means acting upon it. The lifting means, clearly seen in FIG. 5, comprises a lever 110 pivotally mounted on the frame 24 of the apparatus. The lever 110 has a follower 112 thereon which is forced against cam 36 by means of biasing springs 114. The biasing springs 114 are connected at one end to a rod 116 mounted on frame 24 and at the other end to one side of lever 110 by means of a pin 118. The cam plate 36 causes lever 110 to pivot in timed relation to the reciprocation of the bracket member 30. The other end of the ever 110 is formed with an abutment member 120 for abutting the lower side of the flange 88 to raise shaft 58. An upper abutment member 122 is pivotally mounted to lever by means of a pin 124 which can slide in slot 126. A spring-biased plunger 128 acts on one side of abutment member 122 to maintain it in an open position with respect to member 120. The open position of abutment member 122 is limited by the side of member 122 abutting shoulder 130 on the lever 110. In this position the abutment member 122 can engage the upper portion of flange 88 to lower the hollow shaft 58 to the position shown in FIG. 6.
If the apparatus should malfunction, so that abutment member 122 is located below the flange 88 when hollow shaft 58 is in a raised position, then the abutment member 122 will not break when lever 110 is pivoted. The member 122 pivots and slides along slot 126 against the force of spring plunger 128. This prevents the breakage of lever 110 so that the operator can shut down the machine and correct the condition without extensive repairs. Further, since the finger members 90 can lock shaft 58 in a raised position, it is not necessary for lever 110 to follow the raised shaft from one die station to another. As a result, the lever 110 does not move with the reciprocation of bracket member 30.
A rack member 132 is mounted on the forward end of the levers 40 so that it constantly engages gears 80 to rotate shafts 56 and 58 during reciprocation of the bracket member 30, It is necessary that the gear 80 remain in constant contact with rack 132. During reciprocation of bracket 30, gear 80 and shafts 56 and 58 describe an arcuate path away from the face of the dies. This permits finger members 90 to rotate 180 as the workpiece is transferred from one die station to the other without necessitating tilting or raising of finger members 90 in order to provide sufficient clearance for the rotation. In order for the rack member 132 to stay in constant contact with gear 80, it is necessary that the rack move with the gear when the bracket member 30 is reciprocated. Also, to obtain accurate rotation of the shafts 56 and 58, it is necessary that the rack member 132 remain stationary relative to gear 80, so that the gears rotate along a relatively stationary rack. This is accomplished by positioning rack member 132 about recessed sections 134 of the sleeve members 136. The sleeve members 136 are located on the forward end of levers 40 about pins 42. The rack member 132 has slots 138 therein along which sleeve members 136 can slide. Further, rack member 132 is connected to frame 24 by means of a pivotal member 140. The member 140 is pivotally connected to the frame 24 at one end by a pin 142 and to rack member 132 at its other end by a pin 144, as viewed in FIGS. 3 and 4. When rack member 132 is at its innermost position, such that it abuts stops 146 on frame 24, the pin connection 142 is forward of pin connection 144. Thus, when the levers 40 are pivoted to the right, the rack member 132 will only move forward and back in a direction perpendicular to the longitudinal axis of the rack, as shown by the arrows 148. This movement will be repeated when levers 40 move from right to left. It can be appreciated that, with this means for supporting rack member 132, the gears 80 will stay in constant contact with rack member 132. Further, rack member 132 will remain stationary relative to the rotation of the gears. It can also be appreciated that, by simply eliminating the gear 80 about some of the shaft 56, 58 such modified shafts should be secured so that they will not rotate when a work piece is transferred by them from station to station.
The present apparatus may, therefore, be used with a machine when it is desirable to transfer between certain stations without rotation but to rotate or turn the workpiece between other stations. A header or like machine may be constructed in accordance with the present invention, wherein either type of transfer mechanism may be provided selectively at any or all of the several stations by a relatively simple substitution of parts. The transfer mechanism may be adapted to rotate the workpiece between any two adjacent stations where rotation is desired and to effect transfer of a workpiece with rotation between other stations.
It can be further appreciated that the transfer mechanism disclosed is constructed from fewer and simpler parts which operate in a more efficient manner than the transfer mechanisms of the prior art. Moreover, if it is desired, the transfer mechanism is mounted on movable frame member 43, as explained previously. By simply loosening bolts 43a, the frame member 43 can be moved to the desired position and the bolts tightened so as to lock frame member 43 onto frame 24. Thus, by this simple means, the initial distance of transfer fingers 94) from the frame of the dies may be adjusted to accommodate the rotational transfer of either small or large workpieces,
It will thus be seen that the objects set forth above, among those made apparent from the preceding description, are efficiently attained and since certain changes may be made in the above construction without departing from the spirit and scope of the invention, it is intended that all matter contained in the foregoing description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.
What is claimed is:
l. A transfer mechanism capable of moving workpieces from one station to another in a header or similar apparatus having a frame, comprising a. first lever means pivotally mounted to said frame,
b. bracket means pivotally mounted to said first lever means,
c. sliding and rotating means located on said bracket means and having finger means thereon,
d. pivotal means for raising and lowering said sliding and rotating means,
e. a locking means for holding said finger means and in an open raised position, when said pivotal means is not operatively acting upon said sliding and rotating means.
2. The transfer mechanism of claim 1, wherein said sliding and rotating means comprises a first hollow shaft having an extending flange at its were end and slidably mounted on a second central shaft having detent surfaces at its lower end, a gear member mounted on said shafts such that said shafts rotate integrally with said gear member, and wherein said finger means comprises two finger members pivotally mounted at the lower end of said hollow shaft and acted upon by biasing springs to force the lower ends of said finger members toward each other to a workpiece-contacting position.
3. The transfer mechanism of claim 2, wherein said finger members each have a protruding portion thereon such that when said first hollow shaft is raised, said protruding portions pass into said detent surfaces on said second shaft under the force of said biasing springs to maintain said finger members in an open position and said first shaft in a raised locked position.
4. The transfer mechanism of claim 2, wherein said pivotal means comprises a second lever pivotally mounted on said frame and spring biased such that one end of said second lever has upper and lower abutment members thereon located adjacent said flange on said first hollow shaft so that said abutment members can abut said flange to lower and raise said first hollow shaft.
5. The transfer mechanism of claim 4, wherein the lower abutment member is formed as part of said second lever and wherein the upper abutment member comprises a third lever pivotally and slidably mounted on said second lever and biased by plunger means located in said second lever.
6. The transfer mechanism of claim 4, further comprising first drive means which reciprocate said bracket means from a first to second position and second cam drive means which act on said second lever to cause said lever to pivot so as to lower and raise said first hollow shaft in coordination with said first drive means.
7. The transfer mechanism of claim 2, further including rack means positioned on said first lever means such that the first lever means can slidably move relative to said rack means.
8. The transfer mechanism of claim 7, wherein said rack means remain in constant contact with said gear member positioned on said first and second shafts, such that upon rotation of said gears said shafts are correspondingly rotated.
9. The transfer mechanism of claim 8, wherein said rack means comprises a rack member mounted on said first lever means by pin members which pass through slots in said rack member, such that said first lever can slide relative to said rack member, and wherein said rack member is pivotally con nected to said frame by a pivotal member which is pivotally connected at one to said rack member and pivotally connected at the other end to said frame such that upon reciprocation of said bracket means said rack member moves only in a direction perpendicular to the longitudinal axis of the rack member to continually stay in contact with the gear member on said first and second shafts so that said shafts and finger members thereon are correctly rotated.
10. The transfer mechanism of claim 7, wherein said first lever means comprises two U-shaped members, wherein the two arms of said members are pivotally connected to said bracket means and the central portion of said members is pivotally connected to said frame such that upon reciprocation of said U-shaped members said members alternately abut stop means on said frame to accurately position said bracket means.
11. A header, former or similar apparatus having a frame, a die bed carried by said frame and having a plurality of dies on its face, means for transferring the workpieces between adjacent dies, comprising in combination a. first lever means pivotally mounted on said frame,
b. bracket means pivotally mounted on said first lever means,
c. drive means for swinging said bracket means from a firs to a second position,
(1. rotating and sliding means having a gear thereon supported on said bracket means,
e. finger means mounted on said rotating and sliding means and capable of being in a workpiece-contacting closed position or an open locked position,
f. lifting means pivotally mounted on said frame for acting on said rotating and sliding means, and
g. cam means for engaging said lifting means to alternately move said finger means from a closed workpiece-contacting position to a raised locked position.
12. The header apparatus of claim ll, further including rack means positioned on said first lever means such that said first lever means are capable of sliding relative to said rack means, pivotal means for connecting said rack means to said frame so that upon swinging of said bracket means, said rack means moves only in a direction perpendicular to its longitudinal axis to continually remain in contact with said gear on said rotating and sliding means.
13. The transfer mechanism of claim 8, wherein there are a plurality of sliding and rotating means each having finger means thereon and wherein at least one of said sliding and rotating means does not have said gear member so that it will not rotate in transferring a workpiece from one die station to the next.
@2 3 UNITED STATES rATnNr OFFKQE CERTIFIQATE OF CORECHN Patent No. 3,633,766 Dated January 1 197 Inventor(s) Erwin B. Byam and Gregory L; Klein It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown "below:
Column 1, line 25, change "as" to "a"; line 73 change "finger" to read "or". Column 3, line 19,-after "bearing; surface 7 1", first occurrence, insert Column 5 line 3, after "mechanism" insert --can accurately rotate a workpiece through any desired angle as it is transferred from station to station.
The transfer mechanismline 29, after insert --and--; line 30 after "means" second occurrence, delete "and" line 35, "were" should read "lower". Y
Y Signed and sealed this 22nd 'day of August 1972.
EDWARD MELETCHERJR. ROBERT GOTTSCHALK Attesting Officer j Commissioner of Patent