US3446499A - Sheet material handling apparatus - Google Patents

Description

May 27, 1959 .1. s. RlNGLr-:R 3,446,499

SHEET MATERIAL HANDLING APPARATUS Filed Jan. 5, 1968 sheet of INVENTOR. JOHN S. RINGLER ATTORNEYS. I

May-2 7, 1969 J. s. RINGLER 3,446,499

SHEET 'MATERIAL HANDLING APPARATUS Filed Jan. 5. 1968 sheet f3 ors INVENTOR.

JOHN SRINGLER ATTORNEYS.

May 27, 1969 J. s. RINGLER 3,446,499

SHEET MATERIAL HANDLING APPARATUS Filed Jan. s, 196e sheet 3 ar s INVENTOR. JOHN S. RINGLER ATTORNEYS.

United States Patent O 3,446,499 SHEET MATERIAL HANDLING APPARATUS John S. Ringler, Hastings, Mich., assignor to E. W. Bliss Company, Canton, Ohio, a corporation of Delaware Filed Jan. 5, 1968, Ser. No. 695,981 Int. Cl. B65h 5/08, 5/16; B26d 5/22 U.S. Cl. 271-54 8 Claims ABSTRACT F THE DISCLOSURE tacting a subj-acen-t yblank as the working member moves downwardly. Additionally, constraining means are provided lto cause the first member `to move the contacting means horizontally after contacting the blank to thereby move the blank to a final located position.

The present invention is directed ltoward -the art of sheet material handling and, more particularly, to an apparatus for accurately positioning sheets that are in- .termittently fed to a reciprocated Working mechanism.

The invention is especially useful in conjunction with shears or punch presses and will be described with particular reference thereto; however, it is appreciated the invention is capable of broader application and could -be used in associ-ation with -a variety of Ireciprocated sheet material working mechanisms, such as, printing presses, blanking and Ifor-ming machines, etc.

When banks of metal sheet material Aare intermittently fed to scroll shears or punch presses at the high speed required in modern machines, difliculties yare experienced in stopping yand accurately positioning the sheet prior to engagement by the she-ar or punch. As is apparent, the momentum imparted to ythe sheet during the feeding movement causes it to Itend to continue moving after the feed mechanism has ceased acting. In order to overcome 'this problem it has -been ythe practice to permit the feed mechanism to feed the sheet beyond the desired registration point and provide additional mechanism which functions to move the sheet 'back (counter to -the feed direction) against positioning stops.

In general, Ithis additional mechanism included a lever or arm which engaged the forward edge of the sheet and pushed it back. Normally, the arms were driven in time relationship with the shear Iblade or punch, land the tfeeding mechanism, through cam and lever Iarrangements connected -with the main drive of the machine.

Although these prior mechansims performed their intended function satisfactorily, they did have certain drawbacks yand disadvantages. |For example, the arms had to be positioned on the discharge side ofthe machine. In this locati-on the sheet is unsupported Iand droops or bends making orientation for engagement iby the aim difficult. Further, the cam and lever drive arrangements increased the cost of construction of the machine, as well as the maintenance cost.

Other types of pushback mechanisms `we-re utilized which, likewise, were not completely satisfactory. For example, U.S. P-atent 2,339,756 to Aneiros shows an arrangement in which a spring biased carriage and friction wheel arrangement engages the Isheet during its feed movement. The spring is compressed by the forward movement of the sheet and, when the `feed mechanism ceases operating, pushes the sheet back against fixed stops.

The Aneiros arrangement, while eliminating special drive mechanisms, requires readjustment for each change in sheet thickness and lfeed speed. Additionally, lthe adjustments are some what critical 'and time comsuming.

The present invention overcomes the above-described problems and provides a pushback mechanism which d-oes not require special drives. The mechanism is highly simplified and functions without re-adjustment irrespective of sheet thickness or feed speed.

In accordance with the present invention a machine having a vertically reciprocated working member `and means for intermittently feeding blanks to a position beneath the working member is provided with improved means for moving the blanks `to a final located position beneath the working member. The improved means comprise a first member carried by the working member and having la lower end portion extending beneath the working member -when the working member is in its uppermost position. vEngaging means are carried by the lower end portion for contacting a subjacent 'bl-ank as the Working member moves downwardly. Additionally, const-raining means are provided =to Icause `the first member to move the contacting means horizont-ally after contacting `the blank to ythereby move Athe blank to -a final located position.

`In accordance with -a more limited laspect of the invention, the first member comprises a slide member biased downwardly, and the const-raining means include a slideway which carries the slide and is inclined `relative to the path of reciproca-tion of the w-orking member.

As can be seen, because of the relationship between the first member and the constraining means, as the working member moves downwardly, the blank is engaged and moved horizontally Ito a final located position. This arrangement obviates the necessity of providing any special drive means for the locating mechanism and does not require any adjusting means. Further, it functions independent of the speed of feed of the blanks. Addii ltionally, the mechanism is automatically moved in timed relationship with the working member.

Accordingly, a primary object of the present invention is the provision of a highly simplified means for finally locating a lblank beneath a reciprocated working member.

A further object of the present invention is the provision 4of means which function automatically in `response to movement of a reciprocated working member without `requiring special drive mechanism.

Yet another object of the present invention is the provision of a blank or sheet locating mechanism which is especially useful for moving metal sheets to a final position beneath a reciprocated shear or die.

Yet another object of the present invention is the provision of a sheet locating mechanism which has a minimum of moving parts.

These and other objects and advantages will become apparent from the following description when read in conjunction with the accompanying drawings wherein:

FIGURE 1 is a side elevation, somewhat diagrammatic, showing the improved locating means associated with a shear press;

FIGURE 2 is a side elevation similar to FIGURE 1 showing the position of the locating means when the shear press is in its closed or lowermost position;

FIGURE 3 is an enlarged side elevation of the improved positioning means;

FIGURE 4 is a view taken on line 4-4 of and FIGURE 3;

FIGURE 5 is a view taken on line 5-5 of FIGURE 4.

Referring now to the drawings wherein the showings are for the purpose of illustrating a preferred embodiment of the invention only, and not for the purpose of limiting same, FIGURE 1 shows the overall arrangement of a conventional shear press and feeding mechanism A which has mounted thereon, the improved positioning means B formed in accordance with the present invention.

As will become apparent, the actual construction and arrangement of shear press A and its feeding mechanism forms no part of the present invention and has been illustrated merely to show one specific apparatus on which the improved positioning means B isv especially suited for operation. As shown, the shear press includes a lower shearing blade which is mounted in a stationary bolster or bed 12. An upper shearing blade 16 is carried by a vertically reciprocated ram 14 and is arranged to cooperate with blade 10 for shearing material sheets 1 positioned therebetween.

The means for feeding sheets 1 to a position between the blades 10 and 16 includes a conventional horizontally reciprocated feed bar 18 which has a plurality of spaced spring biased feed fingers 20. The feed bar 18 is driven in well-known manner by mechanism not shown, in timed relationship with the reciprocation of the ram. The feed bar functions to feed sheets one at a time to a position between the blades while simultaneously discharging the previously trimmed sheet. A hold down bar 22 is spring biased down to maintain the sheets firmly against the feed table 23 and to maintain the spring fingers 20 down during the reverse reciprocation of the feed bar 18.

In most modern machines the rate of feed of sheets and speed of reciprocation of the ram is quite rapid. For this reason, the momentum gained by the sheets during the feed stroke causes the sheets to tend to move beyond the desired final locating position and/ or make precise locating extremely difficult. Consequently, it has been the practice to overfeed the sheets, that is, to feed them beyond the desired registration or location point and then with the use of separate mechanism push them back against a fixed position adjustable stops, such as spring biased stops 24. A variety of different mechanisms previously discussed have been used for performing the pushback or pullback function. The present invention provides a highly simplified pushback mechanism which does not require special drive connections between it and the feed mechanism or ram.

As best shown in FIGURES 3 through 5, the mechanism includes a first member 30 shown in the form of a slide bar carried in a constraining means 32. The constraining means is in the form of a slideway which, as shown in FIGURE 5, is of generally U-shaped cross-section and closely holds and guides member 30. A transversely extending retainer plate 34 is releasably connected to the slideway by four cap screws 36 and maintains the slide in the slideway.

As shown, the slideway forming member 32 is directly connected to the ram 14 by a pair of cap screws 38. As best shown in FIGURE l, the slide member 3f) is arranged so that its lower end position extends below the end of punch 16 when the ram is in its uppermost position. The member 30 is biased in this position by a pair of springs 40 which are positioned in longitudinally extending openings 42 formed in the slide member. The outer ends of the springs engage an end plate 44 connected to the upper end of the slideway forming member 32 by screws 46. A pin 48 extends transversely through the slide member 30 and limits the lower range of movement of the slide member by engaging the bottom of a groove or slot 50 formed in the slideway forming member 32.

Engaging means are carried at the lower end of slide member 30 for engaging the subjacent sheet as the ram moves downwardly during the working stroke. As will become apparent from the following description, the engaging means could take a variety of forms; however, as shown in FIGURES 3 through 5 the engaging means are preferably in the form of a vacuum cup unit 54 which includes a resilient cup member 56 fitted in a conicallyshaped opening 58 formed in the end of the slide member. 'Ille resilient member 56 is maintained in opening 58 by a large screw 60 which extends vertically through the member. An opening 62 extends through screw 60 and connects with a second opening 64 formed through the side of the slide member. Opening 64 is connected with a source of vacuum which, in a manner to subsequently be described, is selectively connected with the opening and the vacuum cup in timed relationship with the movement of the ram.

The function of the improved positioning or pullback mechanism can best be described by reference to FIG- URES 1 and 2. With a sheet or blank of material positioned between the die in an Overfed location, the ram 14 begins moving downwardly. When the vacuum cup unit 54 engages the sheet a vacuum is pulled on the cup and it firmly grips the sheet. (The control of the vacuum could be by ya variety of mechanisms, such as a valve operated by a cam carried on the main press drive shaft.) With the sheet firmly gripped by the vacuum cup assembly, continued downwardly movement of the ram causes the slide 30 to be moved horizontally under the constraining influence of the slideway 32. Because the slide is biased firmly downward by the spring 40, the blank is moved to the right against stop 24 by its final located position. Should the horizontal movement of the vacuum cup assembly be greater than is needed to bring the blank into engagement with stop 24, the vacuum cup simply slides on the blank. Consequently, at the time the shear blades engage the sheet the sheet is precisely located.

As is apparent, the amount of horizontal movement available can be controlled by varying the angle of inclination of the slideway. In the embodiment shown, the slideway is at an angle of approximately 45 with the path of movement of the ram 14. This gives adequate horizontal movement and additionally allows the slide to move relatively freely in response to :a force against the lower end of the suction cup unit.

Although the preferred embodiment utilizes a suction cup assembly it is obvious that, depending upon the type of material and its surface characteristics, other types of engaging means could be utilized. For example, these engaging means could be a simple friction surface formed from rubber or some other material having good friction characteristics. Likewise, if the sheet or blank material is steel, the engaging means could be a simple magnet.

The invention has been described in great detail sufficient to enable one of ordinary skill in the material handling art to make and use the same. Obviously, modifications and alterations of the preferred embodiment will occur to others upon a reading and understanding of the specification.

Having thus described my invention, I claim:

1. In a machine having a vertically reciprocated working member and means for intermittently feeding blanks to a position beneath said working member, improved means for moving the blanks to a final located position beneath said working member, said improved means comprising:

a first member carried by said working member and having a lower end portion extending beneath said working member when said working member is in its uppermost position;

engaging means carried by said lower end portion for contacting the blank as said working member moves downwardly; and

constraining means for causing said first member to move said contacting means horizontally after contacting said blank to thereby move said blank to a final located position.

first member comprises a slide member and said engaging 5 means comprises a vacuum cup.

4. The improvement as defined in claim 1 wherein said constraining means comprises :a slideway having at least a portion of said first member slideably mounted therein.

5. The improvement as defined in claim 1 wherein said engaging means includes a vacuum cup.

6. The improvement as defined in claim 1 wherein said engaging means includes a magnet.

7. The improvement as defined in claim 1 wherein said engaging means includes a friction surface.

8. The improvement as dened in claim 2 including spring means biasing said slide member downwardly.

References Cited UNITED STATES PATENTS 1/1944 Aneiros 271-60 8/ 1949 MacPheat 83-228 X 10 GERALD M. EoRLENZA, Primary Examiner.

GEORGE F. ABRAHAM, Assistant Examiner.

US. Cl. X.'R.

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