US1493641A - Spring cushion - Google Patents

Description

0. G. NILSON SPRING CUSHION Filed Aug. 29. 1921 2 Shams-Sheet 1 O. G. NILSON SPRING CUSHION Filed Auz. 29 1921 2 mints-Sheet 2 -l 7606 Rio? 0Z0 6. Jilson,

Patented May 13, 1924.

OLOF G. NILSON, OF CHICAGO, ILLINOIS, ASSIGNOR TO MARQUETTE TOOL &. MANUFAC- TURING COMPANY. OF CHICAGO; ILLINOIS, A CORPORATION OF ILLINOIS.

SPRING CUSHION. I

Application filed August 29, 1921.

cago, in the county of Cook and State ofv Illinois, have invented certain new and useful Imprm'ements in Spring Cushions, of

, which the following is a specification.

This invention relates to improvements in spring cushions particularly adapted, though not necessarily limited in its use, for metal drawing. In machines of this character" the metal while being operated upon or drawn is usually held by means of' a draw ring, which ring must exert sutlicient pressurcupon the metal to prevent itfrom wrinkling at the beginning of the stroke and which pressure must not be so great as to cause the metal to tear toward the end of the stroke.

Heretofore the use of springs for yieldingly holding the draw ring has been unsatisfactory by reason of thefact that when used there would be an increase in the resistance caused by the springs as they are compressed towards the end of the stroke, thereby increasing 'to an undesirable extent the gripping action of the draw ring upon the metal which would result in the metal tearing near the end ofthestroke.

Should the springs however be adjusted so as tdprevent the metal from being torn near the end of the stroke the pressure will not be sutlicientat the beginning of the.

stroke to prevent the metal. from wrinkling.

To overcome these difficulties and objections and to provide an in'iproved spring cushion of this type by means of which a substantially constant or even pressure may be obtained throughout the entirestroke or operation upon the work. is one of the objects of the present invention.

A further object is to provide improved means whereby the action of the spring upon the draw ring may be controlled. thereby causing the draw ring to act with an increased or decreased resistance toward the end of the stroke, as may be desired.

A further object is to provide an improved device of this character which is of a simple, durable. cheap and compact construction, adapted to be readily applied to a press and asreadily removed therefrom.

To the attainment of these ends and the accomplishment of other new and useful objects as will appear, the invention con- Serial No. 496,316.

sists in the features of novelty in substantlally the construction, combination and arrangement of the several parts hereinafter more fully described and claimed and shown in the accompanying drawings illustrating this invention and. in which Figure 1 is a top plan View of the cushion.

Figure 2 is a view partly in side elevation, partly in section, and partly broken away, showlng this cushion as applied to a die press.

Figure 3 is a detail sectional View taken on line 33, Figure 1.

Figure t is a perspective view of the spring housing.

Figure 5 is a detail perspective view of the controlling cam or collar.

Referring more particularly to the drawings the numeral 10 indicates the bolster plate of a punch press of any ordinary and well-known construction and mounted upon this plate is a die or forming member 11, co-operating with which die is a draw ring 12, between which ring and the punch 13,

' well-known construction.

The spring cushion which controls the gripping action of the draw ring 12 upon the materialf consists essentially of a housing 15 which is preferably of a cylindrical configuration having a closed end 16. the lower end thereof being open, and the housing is provided with ny i d number of laterally projecting cars 17, each of which cars is provided with a threaded opening 18 therethrough, the body of the housing being preferably cut away as at 19 for the sake of lightness. This housing 15 may be of any desired length and diameter and is provided with an opening 20 through the closed end thereof, around which openin; and Within the housing is preferably provided a boss or projection 21. Arranged below the housing 15 is a supporting element 22, which is connected with the housing preferably by means of a series of bolts 23 which pass loosely through openin 24: in the support '22 and heads 25 on the olts limit the movement of the bolts in one direction with respect to the support. The threaded portions of the bolts 23 engage in the threaded openings 18 of the cars 17- and the bolts are of a length to project above the cars 17 the extremities of the bolts preferably terminating in the reduced smooth portions 26, for a purpose to be hereinafter set forth. Carried by the support 22 are a suitable number of arms 27 pivotally connected to each of the arms and intermediate its ends, as at 28 is a lever 29. The extremity 30 of each of these levers 29 is disputed beneath the housing and above the support 22 and resting upon these extremities 30 of the levers 29 is a plate 31 againstwhich plate one extremity of a coil spring 32 rests and which spring is ar ranged within the housing 15. the other extremity of the spring abutting the inner face of the closed end 16 of the housing 1.) and encompassing the lug or projection 21 on said end.

Throughout the specification and claims the term spring will be employed to designate the element 32, but it is to be understood that this term is not to be considered as a term of limitation, as a spring. rubber, elastic, or any other resilient element may be employed with equal efficiency.

The other end 33 of each of the levers 29 carries a freely rotatable element 3 which latter contacts with the inclined surface 33 of a collar 36 which loosely surrounds the housing 15 and which collar and housing 15 are movable relatively with relation to each other in a direction lengthwise of the housing. The collar may be provided with recesses 37 opening through its lower face 38 and these recesses 37 receive the extremities 26 of the respective bolts 23, so that the collar will be supported by the bolts.

The cushion is supported and held in position upon the press by means of an anchor bolt or rod 39, the end 41 of which passesthrough an opening 42 in the sup port 22 and the extremity of this portion 41 is threaded as at 43 to receive a nut or collar 44 which engages the support 22. This anchor bolt passes loosely through the plate 31and also loosely through the opening 20 in the end 16 of the housing 15, the spring 32 which is arranged within the housing 15 being coiled about the anchor bolt 39. The upper extremity of the anchor bolt 39 is threaded as at 15 and this threaded portion 45 is provided as a means for securing the cushion to the bolster plate 10 of the press. and the support 22 rests upon the nut or collar 44.

When the cushion is thus secured in position the'closed end 16 will be disposed in proximity to the under face of the bolster plate 10 so that the pins 46 which pass loosely through the bolster. plate 10 and which support the draw ring 12 will engage and rest upon the housing 15. so that when the draw ring 12 is depressed bv means of the punch 13 the housing 15 will be shifted so as to compress the spring 32.

'ing will tend to shift the plate 3]. through the medium of the spring 32. The plate 31, however, being supported by the extremities of the levers 29 will tend to rock the levers 29 about their pivots 28 but, as the levers 29 are moved in this manner about their pivots 28. such movement will be retarded by reason of the fact that the rollers 3t contacting with the inclined face of the collar 36 will retard the levers in their pivotal movement and the extent of pivotal movement of the levers will. be controlled by the collar 36. As the rollers 34 are forced against the face 35 of the collar the collar will be caused to move downwardly with. the housing 15 and through the medium of the collar 36 and levers 29 it will be manifest that the action out the spring upon the draw ring 12 will be controlled and the spring will be caused to produce a substantially constant pressure throughout the stroke or operation upon the work. It will be manifest that any tend cncy to cause an increase in the resistance of the draw ring influenced by the spring 32 toward the end of the stroke will be compensated or counteracted by the operation of the rollers 34 upon the face 35'of the collar 36.

It will be manifest that inasmuch as the collar 36 is supported by the bolts 23 the collar will move with the housing 15, and during such movement of the housing the bolts 23 will slide through the support 22. By adjusting the housing 15 with respect to the support 22 through the medium of the nut t4.- the resistance of the spring 32 may be varied at will. After such adjustment and in order to cause the cam or collar 36 to assume its normal relative position with respect to the rollers 34, the bolts 23 should .be adjusted so that their heads 25 will engage the bottom of the support By removing the collar 36 and interwhanging the same for another collar having a different angle of inclination of its face 35. a variation in the leverage of the levers 29 may be obtained.

During operation and asthe housing 15 moves downward the spring 32, will also move bodily downward and the tension on the spring will remain normal during the first portion of the stroke. As the housing 15 moves further downwards the cam 36 travels with it allowing the rollers 34: to move toward the smaller diameter of the cam 36 and by reason of the difierent lengths between the center of the pivot 28 of the levers 29 to the center of the axis of the rollers 34:, and from the center of the pivot had 28 to the extremities 30 of the levers 29, the

31 to recede so that the tension of the spring will be relieved in proportion, and this operation preserves the spring \Vith this improved construction it will be manifest that there is provided a selfcontained spring cushion which may be readily applied to any press and may as readily be removed, and at the same time there is provided a spring cushion in which a substantially constant or even pressure of the draw ring may be obtained throughout theentire stroke or operation upon the work,

and this pressure as well as the leverage of thecontrollin levers may be varied as desired and according to the nature of the work to be performed. It will be further manifest that with this improved construction the device will retain the spring pressure to which it has been adjusted, whether the cushion is applied to the press ordetached therefrom.

While the preferred form of the invention has been herein shown and described. it is to be understood that various'changes may be made in the details of construction and in the combination and arrangement of the several parts, within the scope of the claims. without departing from the spirit of this invention.

What is claimed as new is 1. A spring cushion embodying a reciprocating member. and means embodying a spring, a lever influenced by the spring and a cam device with which the lever cooperates for yieldingly opposing movement of the said member in one direction.

2. A spring cushion embodying a movable member. and means embodying a spring. a lever influenced by the spring and a ram device with which the lever co operates for vieldingl v opposing movement ot'said member in one direction. the said lever and the said cam device being one fixed and the other movable with and with respect to the said member. 7

3. A spring cushion embodying a reciprocating member. means embodying 'aspring. a lever influenced by the spring and a cam device with which the lever co-operates for yieldinglv, opposing movement of the said member in one direction. and means whereby the tension of the said spring may be varied at will.

4. A spring cushion embodying areciproeating member. means embodying a spring, a lever influenced by the spring and a cam device withwhich the lever co operates for yieldinglv opposing movement ofthe said member in one direction, and a single anchoring device for the cushion.

5. A spring cushion embodying a movable member, a fixed member, a lever and cam device interposed between the members,

and a spring interposed between the said movable member and the said lever and operating upon both for converting the variable resistance of said spring into a substan tially invariable resistance to movement of I said movable member.

.6. A spring cushion embodying a movable member, a fixed member. a lever and cam device interposed between the members. a

spring interposed between the said movable member and the said lever and operating upon both for converting the variable 1e sistance of'said spring into a substantially invariable resistance to movement of said movable member. and means whereby the tension of the said spring may be varied at will.

7. A spring cushion embodying a movable member. a fixed member, a plurality of levers and 'cam device interposed between the said members. a spring interposed between the said movable member and the said levers and operating upon both for converting the variable resistance of said spring into a substantially invariable resistance to movement of said movable member. said cam device being movable with the said movable member. and means for adjusting the cam device with respect to the last recited member.

8. A spring cushion embodying a movable memher. a fixed member. a plurality of levels and cam device interposed between the said members. a spring interposed between the said movable member and the said levers and operating upon .both for converting the variable resistance of said spring into a substantially invariable resistance to movement of said movable member. said cam device being movable with the said movable. member. and means removably supporting the cam device.

9. A spring cushion embodying a movable member. a fixed member. a plurality of levers and cam device interposed between the said members. a spring interposed between the said movable member and the said levers andoperating upon both for converting the variable resistance of said spring into a substantially invariable resistance to movement of said movable member. and means for adjusting the cam device with respect to the last recited-member. the last recited means being adapted to vary the tension of the said spring.

10. A spring cushion embodying a movable member. a fixed member. a plurality of levers and cam device interposed between the said members. a spring between the said movable member and the said levers and operating upon both for converting the-variable resistance of said spring into a submovable with the movable member, and means for varying the relative normal po sition of the cam device with respect to the said movable member, while the relative movement of the cam device and lever remains constant.

11. A spring cushion embodying a movable member, a fixed member, a plurality of levers pivotally connected intermediate their ends with the fixed member, a spring interposed between the members and operating upon the movable member and also upon one end of the said levers and tending to move the levers about their pivots to cause the other ends of the levers to approach the movable member, and a cam device interposed between the movable member and the said other ends of the levers to retard the action of the spring upon the levers, said cam and levers operating totransform the variable tension of the said spring into a substantially invariable resistance to movement of the said movable member.

12. A spring cushion embodying a movable member, a fixed. member, a plurality of levers pivotally connectedintermediate their ends with the fixed member. a spring interposed between the members and operating upon the movable member and also upon one end of the said-levers and tending to move the levers about their pivot-s to cause-the other ends of the levers to approach the movable member. a cam device interposed between the movable member and the said other'ends ofthe levers to retard the action of the spring upon the levers, said cam and levers operating to transform the variable tension of the said spring into a substantially invariable resistance to movement of the said movable member, and means for varying at will the tension of the said spring.

13. A spring cushion embodying a mov able-member, a fixed member. a plurality of levers pivotally connected intermediate their ends with the fixed member, a spring interposed between the members and operating upon the movable member and also upon one end of the said levers and-tending to move the levers about their pivots to cause the other ends of the levers to approach the movable member, a cam device interposed between the movable member and the said other ends of the levers to retard the action of the spring upon the levers, said cam and levers operating to transform the variable tension of the said spring into a substantially invariable resistance to movement of the said movable member, and means supporting the cam device for moveto cause the other ends of the levers toap proach the movable member, a cam device interposed between the movable member and the said other ends'of the levers to retard the action of the spring upon the levers, said cam and levers operating to transform the variable tension of the said spring into a substantially invariable resistance to movement of the said movable member, and means supporting the cam device for movement with the movable member, the last recited means being adapted to adjust the cam device with respect to the movable member and also connect the said members for relative movement.

15. A spring die cushion embodying a member adapted to be fixed to a stationary part of a press, a member adapted to be attached to a movable part of said press, levers pivoted intermediate their ends and interposed between said members, a spring arranged to resist movement of the movable member and also operating upon one end of the levers to move the other ends of the levers towards the movable member, anda cam device movable with the movable member and interposed between the said other ends of the levers and the last recited member.

16. A spring die cushion embodying a member adapted to be fixed to a stationary part of a press, a member adapted to be attached to a movable part of said press, levers pivoted intermediate their ends and interposed between said members, a spring arranged to resist movement of the movable member and also operating upon one end of the levers to move the other endsof the levers towards the movable member, a cam device movable with the movable member and interposedbetween the said other ends of the levers and the last recited member, and means for varying at will the normal relative position of the cam device and the said movable member.

In testimony whereof I have signed my name to this specification on this 26th day of August, A. D. 1921.

OLOF G. NILSON.

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