US3554533A

US3554533A - Sheet material-handling apparatus

Info

Publication number: US3554533A
Authority: US
Inventors: Jack E Cox
Original assignee: Gulf & Western Ind Prod Co
Current assignee: EW Bliss Co Inc
Priority date: 1969-04-15
Filing date: 1969-04-15
Publication date: 1971-01-12
Anticipated expiration: 1988-01-12
Also published as: GB1300425A

Abstract

A blank locating device for use with machines having a vertically reciprocable working member designed to register blanks below the working member against fixed rearward positioning stops. The device includes a mounting bracket which is carried on a side of the working member, an arm pivotable on the mounting bracket about a horizontal axis, and a downwardly extending rod which is supported by and vertically slidable within the arm. The rod has at its lowermost end a vacuum cup or other means for engaging the blanks while the working member and rod thereon are in downward motion but still above the blanks. After engagement with a blank, downward movement of the rod stops, and a cam surface on the rod contacts a cooperating surface on the still moving working member as the latter continues in its downward direction. This relative movement of the working member and rod forces the rod lowermost end rearwardly, the length of the rearward positioning stroke depending upon the shape of the cam. Also provided to change the rearward stroke is an adjustment which varies the normal inclination of the rod and thus the starting point for the stroke. The device further includes a third adjusting means for varying the pressure with which the rod engages the blank.

Description

United States Patent [72] Inventor Jack E. Cox

Hastings, Mich.

[21] Appl. No. 816,197

[22] Filed Apr. 15, 1969 Jan. 12, 1971 GU -Western Industrial Products Company,

Grand Rapids, Mich.

a corporation of Delaware by mesne assignments [45] Patented [73] Assignee [54] SHEET MATERIAL-HANDLING APPARATUS 6 Claims, 5 Drawing Figs.

[52] U.S. Cl 271/54, 271/60, 214/1.1, 83/228 [51] Int. Cl B65h 9/10 [50] Field ofSearch 83/278,

253,254,228, 268;214/1.1,1.2,1.3,1.4,1.5,1.6, 1S; 226/(Inquired); 271/54, 60

3,400,838 9/1968 eisetal. 3,446,499 5/1969 Ringler ABSTRACT: A blank locating device for use with machines having a vertically reciprocable working member designed to register blanks below the working member against fixed rearward positioning stops. The device includes a mounting bracket which is carried on a side of the working member, an arm pivotable on the mounting bracket about a horizontal axis, and a downwardly extending rod which is supported by and vertically slidable within the arm. The rod has at its lowermost end a vacuum cup or other means for engaging the blanks while the working member and rod thereon are in downward motion but still above the blanks. After engagement with a blank, downward movement of the rod stops, and a cam surface on the rod contacts a cooperating surface on the still moving working member as the latter continues in its downward direction. This relative movement of the working member and rod forces the rod lowermost end rearwardly, the length of the rearward positioning stroke depending upon the shape of the cam. Also provided to change the rearward stroke is an adjustment which varies the normal inclination of the rod and thus the starting point for the stroke. The device further includes a third adjusting means for varying the pressure with which the rod engages the blank.

PATENTEU 1mm! 3554533 SHEU 1 0F 2 FIG. 2

r g gs 24 g I 20 22 INVENTOR. JACK E. COX

W %M ATTORNEYS.

SHEET MATERIAL-HANDLING APPARATUS The present invention relates to the art of sheet material handling, and more particularly to an apparatus for accurately positioning sheets which are intermittently fed to a vertically reciprocated working member.

The invention is especially useful in conjunction with scroll shears or punch presses, and will be described with particular reference thereto, although it will be appreciated that the invention has broader application and could be used in association with a variety of reciprocated sheet material working mechanisms, such as printing presses, and blanking and forming machines.

When blanks of metal sheet material are intermittently fed to a scroll shear or a punch press at the high speeds required in modern machines, difficulties are experienced in stopping and accurately positioning the blanks prior to engagement by the shear or punch. As is apparent, the momentum imparted to the blank during the feeding movement causes it to continue moving after the feed mechanism has biased acting. In order to overcome this problem, it has been the practice to permit the feed mechanism to feed the blank beyond the desired registration point, and to provide an additional mechanism which functions to move the sheet rearwardly (counter to the feed direction) against fixed rearward positioning stops.

This additional mechanism included a lever or arm which engaged the forward edge of the sheet and pushed it back. The ann was driven in timed relationship with the shear blade or punch, and with the feeding mechanism, through linkages connected with the main drive of the machine.

Although these prior mechanisms performed their intended function, they had certain drawbacks. For example, the arms had to be positioned on the discharge side of the machine, and in this location, the sheet is unsupported and droops or bends making orientation for engagement by the arm difficult. Further, the complex linkages required between the arm and main drive increased the initial cost of the machine, as well as its maintenance costs.

Copending application Ser. No. 695,981, now U.S. Pat. No. 3,446,499 issued May 27, 1969, applied for by John S. Ringler and assigned to assignee of the present application, describes an improved blank locating device which overcomes the above problems and others. This device comprises a slideway carried by the working member, a rod member movable in the slideway, the latter guiding the rod member so that the lower end portion thereof extends beneath the working member when the working member is in its upper most position. A vacuum cup or other engaging means is carried by the lower end of the rod member contacting a blank as the working member moves downwardly. The slideway is so oriented that as the working member continues downwardly after contact, the vacuum cup or other blank-engaging means is constrained to move rearwardly in a positioning stroke moving the blank against the fixed stops.

Although the device of this copending application offered certain advantages. no provision was made for adjustment of the length of the rearward positioning stroke by the vacuum cup or other blank-engaging means, nor for adjustment of the force of engagement with the blank; with the result that the vacuum cup or of the other blank engaging means tended to war unduly during use.

In accordance with the present invention, this disadvantage is overcome by providing, in a blank-locating device of the general character described including a bracket for mounting the device on the side of a vertically reciprocable working member, and a vacuum cup or other blank-engaging means to register a blank rearwardly against fixed stops; the improvement comprising an arm pivotable about a horizontal axis mounted on said mounting bracket; a downwardly extending rod slidable within said arm, the vacuum cup or blank-engaging means being at the lowermost end of said rod; cam means on said rod engageable with the downwardly moving working em member as the member continues downwardly after contact of the vacuum cup or blank-engaging engaging means with a blank, to force the rod lowermost end rearwardly in a positioning stroke; the cam means being removable and replaceable with a differently shaped cam to vary the length of the positioning stroke; further comprising adjusting means to vary the initial inclination of the rod to also vary the length of the positioning stroke; and additional adjusting means to vary the pressure with which the vacuum cup or blank-engaging means contacts the blank.

Preferably the first-mentioned adjusting means comprises a relatively fixed reference surface, a surface movable away from said reference surface with rearward movement of the rod lowermost end; and spacing means to adjust the normal spacing between the reference surface and the movable surface and this thus the initial inclination of the rod.

In particular, the mounting bracket defines a vertically extending reference surface below the plane of the arm pivot axis, the arm defining a cooperating surface also below the plane of the pivot axis spaced from the reference surface, the spacing means comprising an adjustable setscrew threaded into one of said surfaces and engaging the other surface; the

adjusting means further comprising cooperating surfaces above the plane of the pivot axis of said mounting bracket and arm, and biasing spring means under compression between said last-mentioned cooperating surfaces.

Preferably, the device further comprises a spring means compressible with upward movement of the rod relative the mounting bracket, and means to adjust the amount of precompression of the spring means and thus the force with which the rod lowermost end engages a blank.

Accordingly, it is an object of the present invention to provide a further improved and simplified means for locating a blank against rearward fixed stops, and in particular to provide an improved means of the character described which functions automatically in response to movement of the reciprocating working member, without the need for a special drive mechanism, wherein the length of the positioning stroke of the device is adjustable, as well as the force with which the device engages a blank.

The invention, objects and advantages will become apparent from the following specification, with reference to the accompanying drawings, in which:

FIG. 1 is an elevation front view of a blank locating device in accordance with the present invention with the working member in an elevated position;

FIG. 2 is an elevation front view of the device of FIG. 1 with the working member in a lower position;

FIG. 3 is a side detailed elevation view of the device of FIG.

FIGS. 4 and 5 are detailed elevation front views of the blank locating device in the positions of FIGS. 1 and 2, respectively.

Referring to the drawings, wherein the showings are for the purpose of illustrating the preferred embodiment of the invention only and not for the purpose of limiting the same, the FIGS. show a machine A in the form of a scroll shear press having a vertically reciprocable working member B, and a feeding mechanism C, the working member having mounted thereon the improved locating means D in accordance with the present invention invention.

The actual construction and arrangement of the shear press A and its feeding mechanism C form no part of the present invention, and they are illustrated herein simply to show one specific apparatus in which the improved locating means D can be used, and for which it is especially suited. As shown, the shear press includes a lower shear blade 10 which is mounted in a stationary bolster of bed 12. An upper shear blade 14 is carried by a vertically reciprocated ram 16 and is arranged to cooperate with the blade 10 for shearing material blanks 18 positioned therebetween.

The feeding mechanism C feeds the blanks 18 into a position between the

blades

10 and 14, and to accomplish this, comprises a conventional horizontally reciprocable feed bar 20 which has a plurality of spaced apart spring biased feed fingers 22. The feed bar 20 is driven in a well-known manner by a mechanism not shown, in timed relationship with reciprocation of the ram 16. It functions to feed the blanks one at a time into a position beneath the ram 16, between the blades, and in this operation, discharges previously trimmed or but cut blanks from the machine. A holddown bar 24 is spring biased downwardly to maintain the blanks firmly against the feed table. I

In most modern machines, the rate of reciprocation of the ram 16 is vary rapid. For this reason the momentum gained by the blanks during the feed stroke causes the blanks to move beyon d the ir desired final location making precise final location extrem'ely-difficfilti'consequently, it has been the practice to overfeed the blanks, that is to feed then beyond the desired registration or location point, and then with the use of a separate mechanism push then them rearwardly against relatively fixed or adjustable'stop s, such as the spring biased stop 26 shown in FIGS Land 2. A variety of different mechanisms, previously discussed, have been used for performing the pushback or pullback function. The present invention provides a simplified pushbackmechanism which automatically registers the blanks against the biased stops 26, and in particular a mechanism by which the. -positioning rearward stroke is adjustable in lengthj'as well as the force with which the pushback means engages a blank.

As best shown in FlGS. 3-5, the blank-locating device in accordance with the present invention comprises a mounting bracket 30which is mounted on a side surface 32 of the working member B, thebracket having upper and

lower flanges

34 and 36 through'which bolts 38 extend threaded into the surface 32 to hold the bracket onto the working member. lntermediate between the upper and lower flanges, the mounting bracket is provided with outwardly extending, spaced-apart mounting arms 40., grtending outwardly from the plane of the flanges, the arms having horizontally aligned openings 42 into which or through which a pivot pin 44. extends. Pivotably held between the arms 40, rotatable on the pivot pin, is a pivot arm 46 provided with an outwardly projecting extension 48 terminating'in a rounded end portion 50. The rounded end portion is sufficiently large in cross section and length to define a substantially vertically oriented elongated circular slideway 52.

Vertically 'reciprocable in the slideway 52 is a positioning rod assembly 53 comprising a downwardly extending positioning rod 54, which positioning rod is threaded into the upper end (at 56) of a three piece arm 57. The latter includes a downwardly extending first piece 58 aligned with the positioning rod and into which the rod is threaded; a generally horizontally and forwardly extending second piece 60 bolted to the lower end of the first piece, and a cam member 62 bolted to the side 64 of the first piece 58 which faces the ram 16, abouthalfway between the upper and lower ends of the piece 58. The arm horizontal second piece extends until it is partly or almost below the ram 16.

The positioning rod assembly parts including the rod 54 and the armpieces 58 and 60 are hollowed out or bored axially to form a vacuum passageway terminating at the upper end of the positioning rod in an air connection 66, and at the lower end in a vacuum cup 68. To support the latter, the second armpiece 60 is L-shaped having a downwardly extending portion 70.

Also provided in connection with the positioning rod assembly 53 is a locknut 72 which locks the positioning rod 54 to the firstar'ir'tpieceSScd'rrhected thereto, and an upper nut 74 threaded onto the upper end of the rod 54 adjacent the upper surface .76 of the pivot arm 46. A compression spring 78 is seated between the lower surface 80 of the pivot arm and an adjusting nut 82 threaded onto the positioning rod 54 just above the locknut 72. This compression spring biases the positioning rod assembly'downwardly so that the stop nut 74 normally is held against the upper surface 76, the mount of compression in the spring 78 being adjustable by varying the axial position of the adjusting nut 82 on the positioning rod.

Adjacent the lower end of the shear ram, on the side 32,

bracket 84 is provided with two outwardly extending arms 86 between which a pin 88 extends, the pin supportinga cam role roller 90. The dimensions of the bracket 84 and roller 90 are such that the roller normally is slightly spaced from or contacts the front surface 64 of the positioning arm armpiece 58, and on downward movement of the shear ram relative the positioning rod assembly, rollingly engages the cam member 62 forcing the positioning rod assembly rearwardly away from the shear ram an amount dependent upon the shape of the cam.

FIGS. 1 and 4 show the roller 90 above the cam 62, and FIGS. 2 and 5 show the roller 90 against the cam. The guideway 52 is sufficiently long in a vertical direction to con-' strain the movement of the positioning rod to one of outward or rearward pivoting in the latter views about a pivot point defined by the pivot pin 44. During the pivot movement of the positioning rod, the armpiece 58 is guided by 23 extending bracket arms 86 of bracket 84.

Above and below the pivot center of the pivot arm 46, defined by the pin 44, the arm is provided with upper and

lower portions

92 and 94 which are opposite from and face the upper and

lower flanges

34 and 36 of the mounting bracket. A compression coil spring 96 is placed between the complementary upper surfaces (flange 34 and upper portion 92), and a setscrew 98 extends between the complementary lower surfaces (lower flange 36 and lower portion 94). The setscrew is adjustably threaded into a nut 102 welded or otherwise affixed to the lower portion 94, and by turning the setscrew, the spacing between the lower complementary surfaces is varied. This in turn varies the normal inclination of the positioning rod assembly, including the rod 54 and armpiece 58.

Since the setscrew 98 and compression spring 96 are on opposite sides of the pivot pin 44, increasing the spacing between the lower complementary surfaces causes the spring to compress, and decreasing the spacing causes the spring to relax. Obviously, with respect to the position of the vacuum cup 68 or positioning rod assembly lower end, the compression spring biases the vacuum cup or lower end in the direction of the shear rarn.

Operation of the blank locating device should now be apparent. As the shear ram moves downwardly, the positioning rod assembly initially is in the position and has the inclination shown in FIGS. 1 and 4, with the positioning rod substantially vertically oriented. Further movement of the shear ram brings the vacuum cup into contact with a blank on the feeding mechanism table, which blank has previously been advanced forwardly so that part of it extends between the shear blades. Still; further movement of the shear ram causes the cam roller 90 to move downwardly relative to the positioning rod, the

latter sliding upwardly within the pivot arm slideway 52. When the cam roller 90 contacts the cam 62,the positioning rod is pivoted rearwardly against the force of biasing spring 96. This rearward movement in turn forces the blank 18 rearwardly until it comes into contact with the stops 26, accurately registering the foremost end of the blank between the shear blades.

By using a differently shaped cam 62, the vacuum cup can be caused to make a greater or shorter rearward stroke. Accordingly, if the relatively fixed stops 26 are moved forwardly rearwardly from the position shown, a suitably shaped cam can be used to obtain the correct stroke length, avoiding sliding of the vacuum cup across the surface of the blank.

The stroke length can also be changed by means of the setscrew 98. Adjusting the setscrew changes the normal inclination of the positioning rod 54. If the setscrew is turned to increase the spacing between flange 36 and portion 94, the positioning rod is moved rearwardly and the rearward movement of the rod effected by cam 62 is correspondingly decreased, reducing the stroke length. The effect of the cam is increased by decreasing the spacing between the flange 36 and portion 94.

As a further aspect of the invention, the adjusting nut 82 on the positioning rod 54 can be moved upwardly or downwardly to vary the precompression in spring 78 and thus the pressure of the vacuum cup 68 against a blank. By moving the adjusting nut upwardly, this increases the precompression in the spring, increasing the force exerted by the vacuum cup.

Although the preferred mbodiment of the invention utilizes a suction cup, it is obvious, that depending upon the type of material being registered, and its surface characteristics, other types of engaging means can be utilized. For example, a simple friction surface of rubber or some other material having good friction characteristics can be used, or the engaging means could be a magnet.

Although the invention has been described with respect to a specific embodiment, variations and embodiments within the scope of the following claims will be apparent to those skilled in the art.

I claim:

1. A blank-locating device for use with a machine having a vertically reciprocable working member designed to register forwardly advanced blanks within the machine rearwardly against relatively fixed stops comprising:

a mounting bracket adapted to be mounted on a side of the vertically reciprocable working member;

a bracket arm pivotably mounted on a horizontal axis on said mounting bracket;

a downwardly extending positioning rod assembly vertically slidable within said bracket arm;

blank engaging means at the lowermost end of said positioning rod assembly engageable with a blank while the working member is in downward motion;

cam means on said assembly engageable with the downwardly moving working member to force the assembly lowermost end rearwardly after engagement thereof with a blank; and

means for varying the rearward stroke of the assembly.

2. The blank positioner of claim 1 wherein said last-mentioned means comprises means for removably fastening the cam means to the positioning rod assembly the cam means being replaceable with differently shaped cam surfaces.

3. The positioner of claim 1 wherein said last mentioned means comprises;

a reference surface;,

a surface movable away from said reference surface with rearward movement of the positioning rod assembly lowermost end; and

spacing means to adjust the normal spacing of the reference surface from the movable surface and thus the stroke of the positioning rod lowermost end.

4. The positioner of claim 3 wherein said spacing means comprises an adjustable setscrew extending between said reference surface and movable surface.

S. The positioner according to claim 4 including compres sion spring means biasing said reference surface and movable surface together.

6. The positioner of claim I further comprising compression spring means downwardly biasing said positioning rod assembly, including adjusting means to increase or decrease the precompression in said compression spring means

Claims

1. A blank-locating device for use with a machine having a vertically reciprocable working member designed to register forwardly advanced blanks within the machine rearwardly against relatively fixed stops comprising: a mounting bracket adapted to be mounted on a side of the vertically reciprocable working member; a bracket arm pivotably mounted on a horizontal axis on said mounting bracket; a downwardly extending positioning rod assembly vertically slidable within said bracket arm; blank engaging means at the lowermost end of said positioning rod assembly engageable with a blank while the working member is in downward motion; cam means on said assembly engageable with the downwardly moving working member to force the assembly lowermost end rearwardly after engagement thereof with a blank; and means for varying the rearward stroke of the assembly.

3. The positioner of claim 1 wherein said last mentioned means comprises: a reference surface; a surface movable away from said reference surface with rearward movement of the positioning rod assembly lowermost end; and spacing means to adjust the normal spacing of the reference surface from the movable surface and thus the stroke of the positioning rod lowermost end.

5. The positioner according to claim 4 including compression spring means biasing said reference surface and movable surface together.

6. The positioner of claim 1 further comprising compression spring means downwardly biasing said positioning rod assembly, including adjusting means to increase or decrease the precompression in said compression spring means.