US3528318A

US3528318A - Feed control means

Info

Publication number: US3528318A
Application number: US738947A
Authority: US
Inventors: Walter R Huston; Paul D Limpach
Original assignee: Automatic Feed Co
Current assignee: Automatic Feed Co
Priority date: 1968-06-21
Filing date: 1968-06-21
Publication date: 1970-09-15
Anticipated expiration: 1987-09-15

Description

Sept. 15", 1970 W. R. HUSTON FEED common MEANS Filed June 21, 1968 3 Sheets-Sheet 1 7 53 POSITIONING AND LOCKING I 1'6 zo INVENTO WALTER R. HUSTO E PAUL D. LIMPACH Sept. 15, 1970 w, HUSTQN ET AL 3,528,318

FEED CONTROL MEANS Filed June 21, 1968 3 Sheets-Sheet 2 INVENTORS WALTER R. HUSTON PAupD. L-IMPACH Sept. 15, 1970 wQR, HUSTON ETAL 3,528,318

FEED CONTROL MEANS Filed June. 21, 1968 v V r 3 Sheets-Sheet 5 l VENTORS. v HUSTDN v N WALTER R. PAUL. D LlMPACH United States Patent 3,528,318 FEED CONTROL MEANS Walter R. Huston and Paul D. Limpach, Napoleon, Ohio, assignors to Automatic Feed Company, Napoleon, Ohio, a corporation of Ohio Filed June 21, 1968, Ser. No. 738,947 Int. Cl. Fl6c 3/28; F16h 21/20 U.S. Cl. 74-600 7 Claims ABSTRACT OF THE DISCLOSURE An automatically operated mechanism for adjusting the length of the stroke of a reciprocating driven shaft or rack member of a strip stock feeding apparatus. The length of the stroke of the drive shaft or rack is controlled by adjusting the position of a crank pin on a throw block of a metal working machine. Once the desired position of the crank pin has been established, a remotely controlled pressure fluid actuated camming mechanism is energlzed to effectively lock the crank pin in the desired position.

BACKGROUND OF THE INVENTION Field of the invention Apparatus for advancing material of indeterminate length having means for advancing material in a stepby-step manner, including advancing an increment of material and stopping movement thereof, whereby the position of one end of the driving shaft may be varied on the associated throw block and may be automatically locked in position by a remotely controlled cam actuated locking means.

Description of the prior art In the art of metal working, it has been known that metal working machines, such as stamping or punch presses, which perform repetitive operations on material feed in strip form, have been provided with feeding mechanisms which synchronize the advance of the strip stock material into the working area of the machine with the machine in operation, such that the strip material is advanced intermittently at a time when the working faces of the machine are separated from the work upon which they are operating. Typically, the feeder mechanism is driven by means of a reciprocating rack operatively coupled, as by a crank pin, to the throw block of the main drive shaft of the metal Working machine. The advancement of the strip stock material is frequently determined by the stroke of the reciprocating rack. A number of expedients has been employed to adjust the length of the stroke, by adjusting the position of a crank pin, to which one end of the reciprocating rack is pivotally connected. Crank pin position has been established by adjusting the eccentricity of the crank pin on a throw block of the main drive shaft and by adjusting the crank pin position along the length of an arm pivotally mounted for symmetrical oscillatory motion or for shaper motion. One such apparatus is illustrated and described in U.S. Pat. No. 2,728,571, entitled Strip Stock Feeders, Alvin F. Groll. The apparatus illustrated therein involves positioning the crank pin of the throw block connected to the drive shaft in a manner to provide a given degree of eccentricity of the pin with respect to the axis of the drive shaft, and pivotally connecting one end of the rack arm thereto, so that the reciprocation is imparted to the remote end of the rack arm, in accordance with the degree of eccentricity of the crank pin.

None of the known systems is effective to automatically lock the crank pin and the associated driven shaft relative to the throw block. The present invention relates to 3,528,318 Patented Sept. 15, 1970 a means for automatically locking the crank pin eccentricity relative to the throw block.

SUMMARY BRIEF DESCRIPTION OF THE DRAWINGS Other objects and advantages of the invention, as well as a complete understanding thereof, will become readily apparent to those skilled in the art from reading the following detailed description of an embodiment of the invention when considered in the light of the accompanying drawing, in which:

FIG. 1 is a fragmentary side elevational view of the upper portion of a press having a reciprocating drive rack arm for the actuation of a feeder mechanism coupled to its main drive shaft through a linkage including an oscillatory throw block and shows the front View of the crank pin adjusting means of the invention;

FIG. 2 is an enlarged sectional View of a portion of the throw block, the crank pin and the associated locking means therefor taken along the line 2-2 of FIG. 1, with the crank pin retracted to the vicinity of the throw block pivot for purposes of illustration; and

FIG. 3 is a sectional view in a different scale of the apparatus illustrated in FIG. 2, taken along line 33 thereof.

DESCRIPTION OF THE PREFERRE EMBODIMENT Referring to the drawings, the improved crank pin locking means of the invention is illustrated as employed in a mechanically operated punch press. Such a press structure is usually constructed with a frame 10, such as is shown in FIG. 1. A crank shaft and connecting rod, not shown in the figure, are typically included in the upper portion of the press and are arranged to drive a punch carrier 12, which is of the nature of the crosshead, carried in ways in the front upper face of the frame 10. The lower face of the punch carrier 12 is fitted to receive a chuck 14 in which various punches or other tools may be mounted. A bolster 16 is securely mounted from the bottom portion of the frame 10 in such position that it may support a die plate and die (not shown) in position to cooperate with a work punch (not shown) carried by the chuck 14.

A feeder assembly 18 for advancing stock into the working faces of the punch and die is represented in general form in FIG. 1. This feeder can be of the type illustrated and described in U.S. Pat. No. 2,728,571, entitled Strip Stock Feeder, Alvin F. Groll. It typically comprises a U-shaped frame 20, in which feeder rolls 22 and 24 are mounted on heavy shafts (not shown). These rolls are rotated intermittently in timed sequence with respect to the reciprocation of the punch carrier 12 by the rotation of a drive shaft 26 coupled by means of spiral gears (not shown) to the shafts supporting the

feed rolls

22 and 24.

The drive shaft 26, within the limits of the frame 20, carries an over-running clutch and gear assembly (not shown) which meshes with a rack 28. The rack 28 is carried by a connecting rod 30, which at its upper end 32 (FIG. 2) is pivotally connected to a sleeve 34 by self aligning roller bearing means 36. A retainer 35 is suitably secured to rack end 32 to clamp the bearing means 36. The sleeve 34 surrounds the outer peripheral surface of 3 the crank pin 38 in such a fashion that limited relative reciprocal movement can be effected therebetween. The crank pin 38 is provided with an enlarged head portion 40, which slidably fits within a channel formed by inwardly extending edges 41 and 41', in a throw block 42 mounted on the frame of the press on pivot shaft 43.

In accordance with the structure of this invention, the crank pin 38 can be moved with respect to the pivot shaft 43 on the press to adjust the effective length of the stroke of the rack 28, as will be described in greater detail hereinafter. During movement of the crank pin within the channel formed in the throw block 42, the lower surface of the sleeve 34 rides against the outer adjacent surface of the edges 41 and 41 of the throw block 42 in the region of the channel formed therein, while the upper surface of the enlarged head portion 40 of the crank pin 38 rides against the opposite surface of the edges 41 and 41' of the throw block 42 in the regions of the channel formed therein.

A rack guide 44 is pivotally mounted on the drive shaft 26 on a bushing concentric therewith, and serves to hold the rack 28 in mesh with the gear of the drive shaft 26, even though the rack rod executes a connecting rod motion because of its connection to the throw block 42.

Oscillation is imparted to the throw block 42 in synchronism with the motion of the punch carrier 12 by means of connecting rod 31. A throw block 33 mounted for rotating with the drive shaft for the press is pivotally connected to the upper end of rod 31 by trunnion 35 eccentrically mounted with respect to the axis of rotation of the shaft and throw block 33. The lower end of rod 31 is coupled to a trunnion 37 secured to throw block 42 at a point spaced from its mounting pivot 43 so that the connecting rod motion of rod 31 oscillates throw block 42 around to pivot 43.

The operative connection between the rack 28 and the throw block 42, is, in part, effected by means of a lead screw mechanism including a lead screw 46 journalled within a bearing 48 mounted on the throw block 42, and a coupling means 50, which permits the lead screw to the coupled to a power driven means generally designated by reference numeral 52. Drive 52 can be a piston air motor of commercial form supplied through flexible hose 51 valves 53 which advantageously may be solenoid actuated by a positioning and locking control 55. The threaded portion of the lead screw 46 is adapted to be received within an internally threaded bore in the enlarged head portion 40 of the crank pin 38. By turning the lead screw 46 the crank pin 38 may be moved along the length of the lead screw in a direction determined by the direction of rotation thereof. It will be appreciated that the crank pin 38 and its associated sleeve 34 are adapted to be moved within a slot formed in the throw block 42- to effectively adjust the position of the crank pin 38 relative to the center rotation of the throw block 42 at shaft 43.

Aflixed to the upper end of the crank pin 38, by means of a threaded fastener 56, is a fixed frame 58 having a depending peripheral wall portion 60, which contains two pairs of opposed back-up

rollers

62 and 64 respectively mounted for rotation on stub shafts 61 and 63 extending inwardly from the skirts 60 in which they are threadedly mounted.

A fluid pressure actuated cylinder 66 is secured to the fixed frame 58, and has a piston rod 68 extending outwardly therefrom. The piston of cylinder 66 (not shown) is positively driven in both directions of reciprocation to lock the crank pin on extension of rod 68 and unlock the pin on retraction of the rod. Fluid is supplied by solenoid actuated valves 65 mounted on the press frame 10 and passed to the cylinder by flexible hoses 67. The solenoid actuated valves 65 are coupled to the positioning and locking controls 55 through suitable lines whereby the desired actuation thereof is achieved. A wedge block 70 of frame form embracing crank pin 38 is mounted on the distal end portion of the piston rod 68. The elongate reciprocal open center of block receives the extension of the crank pin 38 and permits movement of the wedge block 70 transverse of the axis of the crank pin 38. The flat upper surface of the wedge frame 70 is normal to the axis of crank pin 38. The upper surface of frame sides 71 parallel to the direction of reciprocation of wedge block 70 and are adapted to contact the lower surfaces of the pairs of back-up

rollers

62 and 64. The lower surfaces 72 of the sides 71 are formed to have inclined surfaces diverging from the upper surface along their length to effect a wedging action, as will be described in greater detail hereinafter.

Immediately below the wedge block 70 there is a locking sleeve 74, which surrounds the crank pin 38 and is provided with opposed recesses 75 into which are disposed

cam follower rollers

76 and 78, rotatably mounted on

stub shafts

77 and 79 threadedly secured in tapped bores in the wall of the locking sleeve 74. The

cam follower rollers

76 and 78 are adapted to roll against the respective inclined surfaces 72 of the sides 71 of the wedge block 70.

To militate against any relative rotational movement between the locking sleeve 74 and the crank pin 38, there is a key 73 mounted to extend inwardly from the outer wall of the crank pin 38. The outmost portion of the key 73 is adapted to be received in a key way 73 formed in the inner surface of the locking sleeve 74. As mentioned above, the key 73 and the associated key way 73' cooperate to prevent relative rotational movement between. the locking sleeve 74 and the crank pin 38, while the same permits certain limited relative axial movement therebetween.

The fixed frame 58 of the assembly also has attached thereto a depending guide member 80, having an enlarged foot 82 at the distal end thereof, provided to ride within a slot on throw block 42 formed of the rails 81 superposed on the outer longitudinal margins of the upper face of the throw block. This guide member and the elements of frame 58, including base 83 for cylinder 66, are rigidly joined by webs 84 straddling piston rod 68.

In operation, the desired position of the crank pin 38 with respect to the throw block 42 is initially effected by rotating screw 46 by the means 52 in the desired direction to cause the crank pin 38 to move within the slot formed in the throw block 42. It will be observed that as the crank pin is moved thereby, simultaneous movement of the fixed frame 58 and the associated pressure fluid actuated cylinder 66, guide member 80, and the enlarged foot 82, are also moved thereby. Once the positioning is thereby achieved, the pressure fluid actuated cylinder is actuated by admitting pressure fluid to the cylinder, causing the associated piston to move outwardly, effecting simultaneous movement of the piston rod 68 and the associated cam-' ming wedge block 70. As the wedge block 70 moves outwardly (to the left in FIG. 2), the upper surface thereof rolls against the back-up

rollers

62 and 64, while the inclined surfaces 72 thereof roll against the

cam follower rollers

76 and 78, which, in effect, cause movement of the locking sleeve 74 relative to crank pin 38 along the axis of the pin and downward against the inner race of the selfaligning bearing means 36, as viewed in FIGS. 2 and 3. The inner race 85 of the bearing in turn applies a downward pressure against the drive sleeve 34 at the seat 86 therein, which imparts a pressure against the upper surface of the inwardly extending edge portions of the 41 and 41 of the throw block 42. Simultaneously the back-up

rollers

62 and 64 cause the fixed frame 58 and the associated crank pin 38 to move upwardly, thereby clamping the inner edges 41 and 41' of the throw block 42 between the enlarged head 40 and the base 87 of the drive sleeve 34. It will be manifest that such pinching action caused by the actuation of pressure fluid actuated cylinder 66 effectively locks the crank pin 38 in position.

When it is desired to adjust the position of the crank pin 38 relative to the throw block 42, the pressure fluid within the cylinder 66 on the locking side of the piston is released and fluid pressure is applied to the release side of the piston to retract piston rod 68 and wedge block 70, thereby causing lower surfaces 72 to retreat from

rollers

76 and 78 and release the clamping of flanges 41 and 41 by the base 40 of the crank pin and the base of drive sleeve 34, and the means 52 is operated to effect rotation of the lead screw 46 in the desired direction causing simultaneous movement of the crank pin 38.

According to the patent statutes, We have explained the principles and mode of operation of our invention, and have illustrated and described what we now consider to represent its best embodiment. However, we desired to have it understood that, Within the scope of the appended claims, the invention may be practiced otherwise than as specifically illustrated and described. For example, while an oscillatory mounting of the throw block supporting the adjustable crank pin has been shown, suitable structural modifications of the lock can be made to incorporate it in an adjustable crank pin for a rotating throw block.

What we claim is:

1. An adjustable crank pin-throw block combination comprising: i

a throw block;

means for mounting said throw block for pivotal movement about a pivotal movement about a pivotal axis; means for imparting pivotal movement about said axis;

a crank pin on said throw block;

means for shifting said crank pin relative to the pivotal axis of said throw block; and

remotely controlled power actuated locking means for locking the position of said crank pin on said throw block relative to said pivotal axis.

2. The invention defined in claim 1 wherein said power actuated locking means includes a reciprocatively mounted wedge member to cam said crank pin in tight frictional engagement with said throw block to militate against any relative movement therebetween.

3. The invention defined in claim 2 wherein said power actuated locking means includes a pressure fluid actuated motor.

4. The invention defined in claim 3 wherein said throw block includes a slot for slidingly receiving said crank pin.

5. The invention defined in claim 4 wherein said crank pin includes an enlarged head portion received within the slot of said throw block.

6. The invention defined in claim 2 wherein said crank pin includes an enlarged head portion; and said throw block includes a slot slidingly receiving the head portion of said crank pin.

7. The invention defined in claim 6 including backup roller means afiixed to said crank pin and in rolling engagement with one surface of said wedge member; cam follower means in selective engagement with an opposite surface of said wedge member; and means associated with said cam follower means for engagement with a portion of said throw block whereby when said wedge member is moved in one direction the enlarged head of said crank pin and the last mentioned means are caused by the back-up roller means and the cam follower means respectively to tightly engage said throw block.

References Cited UNITED STATES PATENTS 372,666 11/1887 Giles 74571 2,319,485 5/ 1943 Alabrune 74-600 2,795,968 6/1957 Eriksson 74-571 3,090,250 5/1963 Budlong 74600 3,216,277 11/1965 Groll 74600 1,190,764 7/1916 Hazen 74-600 WESLEY S. RATLIFF, JR., Primary Examiner US. 01. X.R 7