US3684145A

US3684145A - Rectilinear feed apparatus

Info

Publication number: US3684145A
Application number: US89704A
Authority: US
Inventors: Carlton G Jenkins
Original assignee: Sylvania Electric Products Inc
Current assignee: GTE Sylvania Inc
Priority date: 1970-11-16
Filing date: 1970-11-16
Publication date: 1972-08-15
Anticipated expiration: 1989-08-15

Abstract

An apparatus for feeding strip material in a rectilinear direction utilizing a pair of opposed stationary cams having substantially parallel dwell portions which contact pairs of cam followers located within the housings of pairs of opposed clamping assemblies. The cam followers are in direct contact with the jaws of the clamping assemblies and cause the jaws to engage the material once contact is made between the followers and the dwell portions of the stationary cams. The opposed clamping assemblies are affixed at predetermined distances to a pair of chain members which in turn are driven by sprockets affixed to a rotary drive shaft. An external power source provides the method of driving the apparatus.

Description

[451 Aug. 15,1972

. United States Patent Jenkins [57] ABSTRACT An apparatus for feeding strip material in a rectilinear [54] RECTILINEAR FEED APPARATUS direction utilizing a pair of opposed stationary cams having substantially parallel dwell portions which con- Nov. 16, 1970 tact pairs of cam followers located within the housings of pairs of opposed clamping assemblies. The cam fol- [21] Appl. No.: 89,704

lowers are in direct contact with the jaws of the clamping assemblies and cause the jaws to engage the material once contact is made between the followers and the dwell portions of the stationary cams. The op- 343 new one .5 W 6 "B2 m l r C QML Um UH Ur i 0f posed lamping assemblies are affixed at predet ermined distances to a pair of chainmembers which in [56] References Clted turn are driven by sprockets affixed to a rotary drive UNITED STATES PATENTS shaft. An external power source provides the method of driving the apparatus.

3,143,269 8/1964 Eldik.........................226/l72 1,746,221 2/1930 Matteson...................226/l73 9 Claims, 4 Drawing Figures Primary Examiner-Allen N. Knowles Assistant ExaminerGene A. Church AttorneyNorman J. OMalley, Donald R. Castle and William H. McNeill as BUMP-UM 6 m ma w Fr m PATENTED AUG 15 1912 SHEET 1- 0F 2 JNVENTOR. N G. JENKINS A TORNEY RECTILINEAR FEED APPARATUS BACKGROUND OF THE INVENTION This invention relates to feed apparatus and more .particularly to an apparatus for providing a substantially rectilinear feed of strip material from an established source to a designated work station.

Previously known apparatus for feeding strip material to work stations vary from a simple rotating spool pulling the material past the station to a pair of pinch type rollers positioned either before or after the station, depending on the functions of the machine. Another example is a clamp type oscillating feed device in which the material is clamped at one position and moved to another whereby the jaws of the clamp are released and returned to the original position. The jaws then grip the material once again and the cycle repeats itself.

One particular problem regarding apparatus of the clamp or pinch type has been the inability of the apparatus to compensate for changes of material, which has often resulted in physical deformation of the material. A particular problem with the simple rotating spool type, or variation thereof, has been the slippage, or non-continuous transport, of the material.

The above-mentioned problems have resulted in the need for continuous adjustment of the apparatus involved and, when slippage occurred, the rejection of several pieces of material due to variations in overall dimensions.

It is, therefore, believed that an apparatus for providing a continuous rate of feed of strip material to a work station, as well as one which would compensate for alterations in the material without causing physical deformation to that material, would be an advancement in the art.

OBJECTS AND SUMMARY OF THE INVENTION Consequently, it is an object of this invention to provide an improved means for transporting strip material.

It is a further object of the invention to provide an apparatus for transporting strip material which would compensate for dimensional changes in the material without causing physical deformation.

It is a still further object of this invention to provide an apparatus which would provide a continuous nonslipping feed of material.

In accordance with one aspect of this invention there is provided an apparatus for moving strip material in a substantially rectilinear path, as well as insuring that the material will move in a continuous manner, free from possible physical deformation. The apparatus comprises a plurality of individual pairs of clamping assemblies attached to a pair of chain members, the chain members in turn being attached to a series of sprockets. To drive the'apparatus, an external power source is provided which drives a rotary shaft which in turn is connected to the sprockets. Each of the pairs of clamping assemblies has a pair of cam followers, each positioned at opposing ends of the assembly. As the assembly is moved about the apparatus, the cam followers eventually contact the dwell portions of an opposed pair of stationary cams. When this occurs, the 1 cam followers, being in direct contact with the sliding jaws of the clamping assembly, cause the jaws to move together and engage the material. The assembly then continues its movement in a substantially rectilinear I direction until the rise portions of the opposed stationary cams are encountered. At this point, spring members located within the housings of the assembly, and in direct contact with the sliding jaws, force the jaws outward, thereby releasing the material. This releasing however, does not occur until at least one other pair of clamping assemblies has engaged the material at approximately the same position in which the original pair initially made contact.

For a better understanding of the present invention, together with other and further objects, advantages and capabilities thereof, reference is made to the following specification and appended claims in connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an isometric view of the present invention;

F IG, 2 is an elevational view, in section, of one of the clamping assemblies prior to engaging the material;

FIG. 3 is an elevational view, in section, of that same clamping assembly as it has engaged the material; and

FIG. 4 is an isometric view, partially in section, of the locking mechanism of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS As previously mentioned, there is provided an ap paratus which gives a continuous rate of flow to a strip material and also provides a means whereby such material is transported without the possibility of physical deformation, should slight dimensional alterations in the material occur. A plurality of pairs of clamping assemblies, spaced apart on a pair of revolving chains,

are revolved about the apparatus until they contact an opposed pair of stationary cams. Carn followers, located within each pair of the clamping assemblies, contact the dwell portions of the stationary cams and in turn, being in direct contact with the jaws of the assemblies, cause the jaws to move and engage the material.

To more fully illustrate the previously described apparatus, a detailed description of the drawings is provided.

Referring first to FIG. 1, there is shown an isometric view of the present invention. Feed apparatus 11 has an upper and lower block member, 13 and 15, respectively. Lower block member 15 is firmly affixed to table 12. The power for apparatus 11 is provided by an external source (not shown) which drives pulley 17 by belt 18. Pulley 17 in turn is attached to rotary drive shaft 19 which extends through table 12 and lower block member 15, and on into upper block 13, where it terminates. To insure that rotary drive shaft 19 maintains rigid alignment within the apparatus, upper bushing 21 and lower bushing 21 are provided. Upper bushing 21 is attached to the under surface of upper block member 13 whereas lower bushing 21' is attached to the upper surface of lower block 15.

Attached to rotary drive shaft 19 is a pair of

sprocket members

25 and 25 respectively, which in turn drives

chain members

29 and 29.

An idler shaft 33, similar to rotary drive shaft 19 but not having an external drive means attached is positioned at the opposite end of the apparatus 11 from drive shaft 19 and has components similar to those described for drive shaft 19, those being a pair of bushings and corresponding pair of sprocket members. For reasons of clarity as to the working procedures of the remaining components of feed apparatus 11, these bushings and sprocket members are not shown in the drawing. The sprockets on idler shaft 33 are spaced apart the same distance as sprockets and 25' on drive shaft 19, thereby assuring that

chain members

29 and 29 will revolve with an equally spaced relationship throughout the operation of the apparatus.

Attached to

chain members

29 and 29 are a plurality of pairs of clamping assemblies which sequentially engage and disengage strip material 37 as they revolve about. The pairs of clamping assemblies 35 are spaced at equal intervals on the chain members, and each comprise an opposing pair of housings 39 and 39'. These housings have

cam followers

41 and 41 positioned at each end which are in direct contact with sliding

jaws

43 and 43 respectively. As the pair of clamping assemblies 35 revolve about, they approach on one side of the feed apparatus a pair of opposed

stationary cams

45 and 47. These cams, as shown, have similar opposed fall portions 49 and 49', dwell

portions

51 and 51, and rise

portions

53 and 53, respectively.

Dwell portions

51 and 51 are opposed in a substantially parallel spaced relationship. Rise portion 53 of stationary cam 45 is drawn in phantom to more clearly show the various stages of operation of the pairs of clamping assemblies 35. In like manner, one of the pairs of clamping assemblies is drawn in phantom to more clearly show how

chain members

29 and 29 are engaged with

sprockets

25 and 25 respectively.

When the clamping assemblies reach a certain position during the operation, cam followers 41 and 41' contact the

dwell portions

51 and 51 of

stationary cams

45 and 47 respectively. In doing so, they are each depressed against their respective sliding jaws, causing them to close together. After closing together a preadjusted distance, the jaws engage strip material 37 and clamp it firmly. The assemblies continue to move the entire length of the dwell portions until the opposed rise portions 53 and 53' are encountered. Once this occurs, the pressure against the cam followers is released and they return to their original position before contacting the stationary cams. This return is made possible by internal springs which act directly against the jaws which in turn push the cam followers outward. The operation of these springs will be more clearly shown in FIGS. 2 and 3.

A locking mechanism 57 is shown and will be explained later in the specification during the description of FIG. 4. Also shown is the adjusting mechanism 58, to be likewise explained with the description of FIG. 4.

Jaw apparatus 11 may be driven either intermittently or non-intermittently, depending on the type of machine which it serves. Both methods of driving the apparatus may be used without altering any of its components.

In FIG. 2 can be seen one of the pairs of clamping assemblies 35 prior to engaging the strip material (not shown). Cam followers 41 and 41' are shown in their respective positions within the housings 39 and 39'. From FIG. 2 it is clear to see that one pair of clamping assemblies comprise several similar opposing components.

Cam followers

41 and 41, housings 39 and 39' and

jaws

43 and 43 are all substantially similar in structure and function throughout the apparatus. This not only provides ease of maintenance, but also allows for greater interchangeability of parts. Because of the similarity of parts, it is only necessary to describe one side of the pair 35 and how the components on this side function during the operation. It is understood that the components comprising the opposing side of the pair are acting in similar manner and at the same time period as those on the first mentioned side.

Cam follower 41 is in direct contact with sliding jaw 43 at all times during the operating of the apparatus, and is guided in its travel by arms 59 and 60 which move within

channels

61 and 63 respectively, once contact is made with dwell surface 51 (shown in phantom). When this occurs as shown in FIG. 3, cam follower 41 is pressed against sliding jaw 43 which in turn moves downward. Sliding jaw 43 is also moving upward at the same period of time.

To assure that the sliding jaws 43 and 43' return to their original positions after contact with the stationary cams has terminated, a pair of

springs

65 and 65" are provided. These springs are in direct contact with the jaws and continually exert pressure against them. Piston 67, besidesproviding a base for the springs to act against the jaws also provides a means whereby proper alignment of the jaws is maintained. The piston is fitted within a cylindrically shaped channel 69 which has as its walls the sliding

jaws

43 and 43 as well as a stationary base member 70. This piston assures that the jaws will mate in proper alignment with the strip material. Misalignment of these parts could cause physical deformation to the material, as well as an erratic feed pattern. The pair of clamping assemblies 35 is affixed to chain members 29 and 29' by two pairs of opposing L-shaped members 71. Although many methods of afiixing these assemblies is possible, welding is the method shown here.

In FIG. 3 is shown the pair of clamping assemblies 35 as it has engaged the strip material 37. Contact has been made between the dwell portions 51 and 51' of the stationary earns 45 and 47 and the

cam followers

41 and 41 respectively, causing the jaws to move together. Should the pressure of this clamping be too great for the material, a relief feature is provided within each pair of assemblies, this feature being a pair of opposing dish-shaped washers 73 and 73'. These pairs of washers, being resilient, will compress together and relieve the excessive pressure. In FIG. 3 can also be seen the positions of the springs 65 and 65' as they have been compressed within cylindrical shaped channel 69.

FIG. 4 is an isometric view, partly in section, showing the locking mechanism 57 as well as the adjusting mechanism 58. Adjusting mechanism 58 comprises a threaded shaft 75 extending through base member 77 and into a recessed area 79 of a dovetail member 80. The procedure for lowering the upper cam 45 down until the proper amount of clamping pressure is determined is first to loosen the two screws 81 which are threaded into a retaining dovetail member 83. Two other screws (not shown) are threaded into a second retaining dovetail member 83 and must be loosened also. Once this is completed, the retaining pressure against the dovetail member is released allowing it to move freely. Nut 85 is then loosened, and with an Allen wrench or similar tool, threaded shaft 75 is turned against the lower surface 87 forcing the dovetail member 80 downward. This, in turn, forces cam 45 downward, because the cam and the dovetail member 80 are directly joined by common shaft 95.

Once the cam is lowered sufficiently to act against the pairs of clamping assemblies so that the jaws of the assemblies are engaging the strip material, nut 85 is tightened down, thereby restricting any further movement of threaded shaft 75. Screws 81 and those threaded into second retaining dovetail member 83, are then tightened, and dovetail member 80 is firmly retained. It is important to note that arm 89 of locking mechanism 57 is in the lock position during this operation, as distinguished by the lettering on the face of stationary cam 45. To disengage the strip material the only step necessary is to raise arm 89 which in turn raises cam 45. This is made possible due to block member 91 having a cylindrical end 93 which has a central axis non-concentric with the axis of shaft 95. Therefore, when arm 89, being firmly attached to block member 91, is turned upward, cylindrical end 93 rotates about common shaft 95, and in doing so, moves the thicker walled portion of cylindrical end 93 to the upper side of the shaft. Because the shaft is firmly attached to the now stationary dovetail member 80, cam 45 is forced upward. The pressure is now relieved on the material. This locking mechanism makes threading and unthreading the machine substantially easier.

Holding screw 97, being threaded into common shaft 95, acts against surface 99 of the shaft, and in doing so holds block member 91 and arm 80 firmly-in position.

To assure a proper vertical movement of cam 45 during locking and unlocking, guide rails 100 and 100' are provided. To also assure that cam 45 is held against upper block member 13 at all times, holding bolt 101 is provided. This bolt is kept loose enough, however, to allow the cam to move vertically without excessive fn'ction. An additional holding bolt 101' on the opposing side of the locking mechanism 57 is provided but not shown in FIG. 4 so as to more clearly show the components of the locking and adjusting mechanism. It may be seen in FIG. 1, however.

While there have been shown and described what are presently considered the preferred embodiments of this invention, it is obvious to those skilled in the art that various changes and modifications may be made therein without departing from the scope of the invention as defined by the appended claims.

lclaim:

1. An apparatus for rectilinearly moving strip material through the agency of sequentially engaging and disengaging substantially similar pairs of opposed clamping assemblies being operated in a sequentially continuous manner, said apparatus comprising:

means for initially engaging a free end of said material between the jaws of a first pair of said opposed clamping assemblies said means comprising a pair of opposed stationary cams having dwell portions established thereon which contact a pair of cam followers, each of said cam followers located within a housing of each of said first pair of said opposed clamping assemblies and being in direct contact with each of said jaws of said first pair of said clamping assemblies, said cam followers causing said jaws to move to engage said material when contact between said cam followers and said dwell portions of said opposed stationary cams is accomplished;

means for moving said first pair of said opposed clamping assemblies a given distance in a substantially rectilinear direction;

means for engaging a second pair of said clamping assemblies with said material while said first pair of said clamping assemblies is still engaged; and

means for subsequently disengaging said first pair of said opposed clamping assemblies, said means comprising a pair of resilient members located within said housings of said first pair of said clamping assemblies which in turn act against said jaws, causing them to move away from said material when contact between said cam followers and said opposed stationary cams is terminated.

2. The apparatus according to claim 1 in which said means for engaging said second pair of said opposed clamping assemblies with said material is accomplished in like manner to that as prescribed in claim 1 for said first pair of said opposed clamping assemblies.

3. The apparatus according to claim 1 in which said means for moving said first pair of said opposing clamping assemblies a given distance in a substantially rectilinear direction comprises a pair of chain members, each of said chain members being driven by a rotating sprocket member, said clamping assemblies being attached to said chain members in a predetermined spaced relationship.

4. The apparatus according to claim 3 in which said pair of chain members are vertically spaced in a substantially parallel arrangement whereby said sprocket members for driving said chains are attached to and driven by a rotating shaft, said rotating shaft in turn being driven by a power source located externally from said apparatus.

5. The apparatus according to claim 1 in which said resilient members located within said housings of said clamping assemblies comprise a plurality of springs, said springs acting directly against said jaws of said clamping assemblies.

6. The apparatus according to claim 1 in which a relief feature is provided within each pair of said opposed clamping assemblies to thereby relieve possible excessive pressure exerted against said material by said jaws of said clamping assemblies during engagement of said material by said jaws.

7. The apparatus according to claim 6 in which said relief feature comprises a pair of opposing resilient dish-shaped washers, said washers thereby able to com-' press when said excessive pressure is exerted on said material.

8. The apparatus according to claim 1 in which an adjusting mechanism is provided for moving one of said opposed stationary cams prior to operation-of said apparatus to thereby control the amount of pressure exerted on said material by said jaws of said clamping assemblies.

9. The apparatus according to claim 8 in which said adjusting mechanism comprises a threaded shaft extending through a stationary base member and acting against a movable dovetail member, said dovetail member directly joined to said cam.

Claims

1. An apparatus for rectilinearly moving strip material through the agency of sequentially engaging and disengaging substantially similar pairs of opposed clamping assemblies being operated in a sequentially continuous manner, said apparatus comprising: means for initially engaging a free end of said material between the jaws of a first pair of said opposed clamping assemblies said means comprising a pair of opposed stationary cams having dwell portions established thereon which contact a pair of cam followers, each of said cam followers located within a housing of each of said first pair of said opposed clamping assemblies and being in direct contact with each of said jaws of said first pair of said clamping assemblies, said cam followers causing said jaws to move to engage said material when contact between said cam followers and said dwell portions of said opposed stationary cams is accomplished; means for moving said first pair of said opposed clamping assemblies a given distance in a substantially rectilinear direction; means for engaging a second pair of said clamping assemblies with said material while said first pair of said clamping assemblies is still engaged; and means for subsequently disengaging said first pair of said opposed clamping assemblies, said means comprising a pair of resilient members located within said housings of said first pair of said clamping assemblies which in turn act against said jaws, causing them to move away from said material when contact between said cam followers and said opposed stationary cams is terminated.

7. The apparatus according to claim 6 in which said relief feature comprises a pair of opposing resilient dish-shaped washers, said washers thereby able to compress when said excessive pressure is exerted on said material.

8. The apparatus according to claim 1 in which an adjusting mechanism is provided for moving one of said opposed stationary cams prior to operation of said apparatus to thereby control the amount of pressure exerted on said material by said jaws of said clamping assemblies.