US2710062A

US2710062A - Hold-down devices for side trimming shears

Info

Publication number: US2710062A
Application number: US270680A
Authority: US
Inventors: Carl T Lanstrom
Original assignee: United States Steel Corp
Current assignee: United States Steel Corp
Priority date: 1952-02-08
Filing date: 1952-02-08
Publication date: 1955-06-07
Anticipated expiration: 1972-06-07

Description

June 7, 1955 c. T. LANsTRoM 2,710,062

HOLD-DOWN DEvIES FOR SIDE TRIMMING SHEARS Filed Feb. 8, 1952 2 sheets-sheet 1 INVENToR: Cna 7,'4/1/57/90/14,

June 7,l 1955 c. T. LANsTRoM 2,710,062

HOLD-DOWN DEVICES FOR SIDE TRIMMING sHEARs Filed Feb. 8, 1952 2 Sheets-Sheet 2 f FISE- HOLD-DOWN DEVICES FR SIDE TRIMMING SHEARS Cari T. Lanstrom, Concord, Calif., assignor t United States Steel Corporation, a corporation of New Jersey Application February 8, 19452, Serial No. 270,680

7 Claims. (Cl. 164-60) This invention relates to improved devices for holding down metal strip while passing through side trimming shears.

The practice in manufacturing metal strip is to trim its side edges so that they are uniform in the finished product. This side trimming is accomplished by feeding the strip past shears which have rotatable knives situated adjacent each side edge of the strip. Such shears require hold-down devices for retaining the strip, and previous hold-downs with which I am familiar have been in the form of lixed shoes that contact both the upper and lower faces of the strip. For steel strip the shoes are of a softer metal, such as brass, in order not to scratch the strip surface. These shoes have the disadvantage that on one face of the strip small particles produced during cutting tend to lodge between the shoe and the strip surface and seriously scratch the latter. o minimize the chance for such particles to get under the shoes, the shoes are spaced a considerable distance inwardly f of the shear knives, where they do not retain the strip properly and do not always prevent cobbling and torn edges.

An object of the present invention is to provide improved hold-down devices which overcome the foregoing disadvantages; that is, they can engage the strip closely adjacent its edges to furnish proper holding action and yet eliminate the possibility of scratching the strip surface.

A more specific object is to provide improv-ed holddown devices which include adjustably mounted rotatable wheels engageable with the upper face of the strip adjacent its opposite side edges, whereby any particles caught on the wheel surface at most dent the strip surface without scratching it and the particles easily can be removed. p

. In accomplishing these and other objects of the invention', I have provided improved details of structure, a

preferred form of which is shown in the accompanying` drawings, in which:

Figure 1 is a top plan View of side trimming shears which are equipped with an improved hold-down device embodying features of thepresent invention;

Figure 2 is a front elevational view of the structure shown in Figure 1;

Figure 3 is a vertical sectional view taken substantially on line III-IH of Figure 1;

Figure 4 is a horizontal sectional view taken substantially on line IV-IV of Figure 5;

Figure 5 is a vertical sectional view taken substantially on line V-V of Figure 4; and

Figure 6 is a vertical sectional view taken substantially on line VI-VI of Figure 5.

Figures l and 2 show somewhat schematically a pair of side trimming shears which include spaced apart

housings

10 and 12. One or both of these housings are adjustable toward and away from the center line of the strip to accommodate strip of different widths. Each housing carries lower and upper

rotatable knives

13 and 14. A continuous strip S is fed through the space between said housings and is supported on its underside by the usual shoes 15 (Figure 2). The shear and feed means are not United States Patent C shown in detail since they can be of any standard or desired construction. The lower knives are offset inwardly with respect to the upper knives. Consequently any loose cuttings or other particles beneath the strip tend to move outwardly away from the strip and do not lodge between the shoes 15 and the bottom surface of the strip. The lower knives in fact act as barriers against such particles reaching the shoes. However, loose particles above the strip tend to move inwardly over the strip surface where they ordinarily can lodge under the hold-down device.

The hold-down device of the present invention comprises brackets 16 and 17 mounted on the entry ends of the two

housings

10 and 12. A pair of rods 18 and 19 are iixedly supported in bracket 16 and adjustably supported in bracket 17 so as not to interfere with sidewise adjustment of the housings. Three supporting

arms

20, 21 and 22 are slidably mounted on rods 18 and 19. Adjusting bolts 24 are Xed to brackets 16 and 17 and are adjustably received in openings through the outside arms and 22 (Figure 3). Positioning nuts 25 are threadedly engaged with said bolts for holding the arms in adjusted position. Once the outside arms are adjusted with respect to the housings, it is unnecessary to vary their adjustment except to position them for knives of different thickness, although of course these arms move with the housings as the latter are adjusted to accommodate strip of different widths. During such adjustment arm 22 can move back and forth along the rods 18 and 19 with the housing 12. The central arm 21 has a locking screw 26 engageable with one of the rods 1S 0r 19 (Figure l). Normally this arm is adjusted to a position over the center line of the strip, which position varies with the width of strip.

Each of the

arms

20, 21 and 22 extends from the rodsv 18 and 19 to a position over the axes of rotation of the

knives

13 and 14, and each carries a

wheel

27, 2S and 29 respectively. Each of the wheels has a tire that en gages the strip S opposite one of the shoes 15. As shown in Figure 6, the line of contact between the tire 30 of the wheel 29 and the upper surface of the strip S lies in the same vertical plane a-a as the axes of rotation of the upper and lower knives. The lines of contact between the tires 30 of the

wheels

27 and 28 and the strip also lie in this same vertical plane. The tires are of smooth non-abrasive material, such as hard ber, and do not scratch the strip surface. The Aouter faces of the

outside wheels

27 and 29 are dished to receive the knife hubs as shown in Figure 5, and the tires are relatively wide to furnish a relatively long line of contact with the strip.

Figures 4, 5 and 6 show in detail the mounting means for the wheel 29 on the arm 22, the mounting means for the wheels on the other arms being similar. This mounting means includes a vertically movable slide 31 which rides in a groove 32 in the face of the arm, where it is held by gibs 33. The slide carries a wheel bearing 34 which extends through a slot 35 in the arm and in which the wheel shaft is rotatably journaled. l The upper part of the slide carries a nut 36. An adjusting screw 37 is journaled in the upper part of the arms and threadedly engages nut 36, so that manual rotation of the screw raises or lowers the slide, wheel bearing and wheel.

In setting up the hold-down device, the

outside arms

20 and 22 are adjusted on the rods 18 and 19 for the particular knives used in the shears. The adjustment is such that the

outside wheels

27 and 29 lie closely adjacent the upper knives 14 and preferably their edges overlap the edges of the lower knives 13, as Figure 5 shows. Next the

housings

10 and 12 are positioned so that the spacing between their knives correspond with the desired strip width in accordance with usual practice. The central arm 21 then is moved to a position such that its wheel 28 lies directly over the center line of the strip. The three wheels are raised by rotation of their adjusting screws 37 and the strip is threaded through the shears and holddown. The wheels then are lowered by rotation of screws 37 in the opposite direction until they bear against the upper surface of the strip with the desired pressure. The strip now can be fed through the shears.

It is seen that the three wheels function as hold-downs for the strip and that the outside wheels are situated closely adjacent the knives where they prevent cobbles and torn edges. Any cuttings from the strip which come against the wheel surfaces either are thrown off by centrifugal force or easily can be cleaned od. There is no likelihood of such particles scratching the strip surface.

While I have shown and described only a single embodirnent of the invention, it is apparent that modifications may arise. Therefore, I do not wish to be limited to the disclosure set forth but only by the scope of the appended claims.

I claim:

1. In a side trimming shear for metal strip which includes a pair of spaced apart housings, lower and upper rotatable knives carried by each of said housings and adapted to trim the strip edges, and shoes for supporting the strip on its underside, the combination with said housings of a hold-down device which comprises support means carried by the housings, a pair of arms carried by said support means, each of said arms being adjacent a different one of said housings and spaced inwardly thereof, wheel bearings carried by each of said arms, means on each of said arms for individually adjusting the wheel bearing thereon in a vertical direction, wheels mounted in each of said wheel bearings for rotation on axes which are independent of the axes of rotation of said knives, said wheels having smooth non-abrasive surfaces engageable with the upper face of the strip opposite said shoes and closely adjacent said knives, and additional means engageable with the upper face of the strip at its center line.

2. A combination as defined in claim 1 in which said additional means includes an arm carried by said support means, and a wheel rotatably supported by said last named arm.

3. In a side trimming shear for metal strip which includes a pair of spaced apart housings adjustable toward and away from each other, lower and upper rotatable knives carried by each of said housings and adapted to trim the strip edges, and shoes for supporting the strip on its underside, the combination with said housings of a hold-down device which comprises a support extending therebetween and being adjustably mounted on one of said housings, outside arms and a central arm mounted on said support and extending over the knife axes, wheel bearings carried by each of said arms, means on each of said arms for individually adjusting the wheel bearing thereon in a vertical direction, and wheels carried by said wheel bearings for rotation on axes which are independent of the axes of rotation of said knives, said wheels having smooth non-abrasive surfaces engageable with the upper face of the strip opposite said shoes, the wheels on said outside arms lying closely adjacent said upper knives, said central arm being adjustable along said support to enable the wheel thereon to be placed over the center line of the strip.

4. In a side trimming shear for metal strip which includes a pair of spaced apart housings adjustable toward and away from each other, lower and upper rotatable knives carried by cach of said housings and adapted to trim the strip edges, and shoes for supporting the strip on its underside, the combination with said housings of a hold-down device which comprises a pair of rods xed to one housing and adjustably mounted on the other and extending between the two housings, outside arms and a central arm mounted on said rods for adjustment therealong and extending over the knife axes, wheel bearings carried by each of said arms, means on each of said arms for individually adjusting the wheel bearing thereon in a vertical direction, and wheels carried by said wheel bearings for rotation on axes which are independent of the axes of rotation of said knives, said wheels having smooth non-abrasive surfaces engageable with the upper face of the strip opposite said shoes, the wheels on said outside arms lying closely adjacent said upper knives and having their outer faces dished to receive the knife hubs, adjustment of said central arrn along said rods enabling the wheel thereon to be placed over the center line of the strip.

5. In a side trimming shear for metal strip which in cludes a pair of spaced apart housings adjustable toward and away from each other, lower and upper rotatable knives carried by each of said housings and adapted to trim the strip edges, said lower knives being odset inwardly with respect to said upper knives, and shoes for supporting the strip on its underside, the combination with said housings of a hold-down device which com. prises a pair of rods fixed to one housing and adjustably mounted on the other and extending between the two housings, outside arms and a central arm mounted on said rods for adjustment therealong and extending over the knife axes, wheel bearings carried by each of said arms, means on each of said arms for individually adjusting the wheel bearing thereon in a vertical direction, and wheels carried by said wheel bearings for rotation on axes which are independent or" the axes of rotation of said knives, said wheels having smooth non-abrasive surfaces engageable with the upper face of the strip opposite said shoes, the wheels carried by said outside arms lying closely adjacent said upper knives and having their outer faces dished to receive the knife hubs and their edges overlapping said lower knives, adjustment of said central arm along said rods enabling the wheel thereon to be placed over the center line of the strip.

6. In a side trimming shear for metal strip which includes a pair of spaced apart housings adjustable toward and away from each other, lower and upper rotatable knives carried by each of said housings and adapted to trim the strip edges, and shoes for supporting the strip on its underside, the combination with said housings of a hold-down device which comprises a support extending therebetween and being adjustably mounted on one of said housings, outside arms and a central arm mounted on said support and extending over the knife axes and having vertical slideways formed therein, wheel bearings mounted in said slideways for individual vertical adjustment, rotatable adjusting screws connecting each of said arms with the bearings mounted therein, and wheels carried by said wheel bearings for rotation on axes which are independent of the axes of rotation of said knives, said wheels having smooth non-abrasive surfaces engageable with the upper face of the strip opposite said shoes, the wheels on the outside arms lying closely adjacent said upper knives, said central arm being adjustable along said support to enable the wheel carried thereby to be placed over the center line of the strip,

7. A combination as dened in claim 6 in which the wheels carried by said outside arms have dished outer faces receiving the knife hubs.

References Cited in the tile of this patent UNITED STATES PATENTS 824,694 Irwin June 26, 1906 1,291,931 Kornas Ian. 2l, 1919 2,014,248 Evans Sept. 10, 1935 2,097,636 Moore Nov. 2, 1937 2,204,904 Moore June 18, 1940 FOREIGN PATENTS 371,794 Great Britain Apr. 28, 1932