US3282076A

US3282076A - Brakes for forming plate or sheet workpieces

Info

Publication number: US3282076A
Application number: US332202A
Authority: US
Inventors: Jr Percy L Cady
Original assignee: Delaval Turbine California Inc
Current assignee: IMO Industries Inc; Delaval Turbine California Inc
Priority date: 1963-12-20
Filing date: 1963-12-20
Publication date: 1966-11-01
Anticipated expiration: 1983-11-01
Also published as: DK108521C; DE1452748A1; NL6414670A; FR1417915A; CH445419A

Description

BRAKES FOR FORMING PLATE OR SHEET WORKPIEGES Filed Dec. 20, 1963 P. L. CADY, JR

Nov. 1, 1966 5 Sheets-Sheet l N &

INVENTOR Perm A. C/wv J).

-Way, ATTORNEYS Nov. 1, 1966 Filed Dec. 20, 1963 P. L. CADY, JR 3,282,076

BRAKES FOR FORMING PLATE OR SHEET WORKPIECES 5 Sheets-Sheet 2 INVENTOR Paecr L. @wr

WWMM

ATTORNEY6 Nov. 1, 1966 P. L. CADY, JR 3,282,076

BRAKES FOR FORMING PLATE OR SHEET WORKPIECES Filed Dec. 20, 1963 5 Sheets-Sheet 5 f/ ATTORN EYS United States Patent 3,282,076 BRAKES FOR FORMING PLATE 0R SHEET WORKPIECES Percy L. Cady, In, Media, Pa., assignor, by mesne assignments, to De Laval Turbine Inc., Trenton, N.J., a corporation of Delaware Filed Dec. 20, 1963, Ser. No. 332,202 13 Claims. (Cl. 72-35) This invention relates to brakes for forming plate or sheet workpieces, and more particularly for the cold bending of metal plate and the like.

In a typical machine of this character, the workpiece, for example a long piece of steel plate, is placed upon the top or working surfaces of a pair of working members or aprons which lie in parallel vertical planes and extend horizontally from end to end of the machine and at the two ends are pivotally supported by hearing means mounted in vertical columns of the framing of the machine. Above the working members is a clamping ram, in the form of a thick plate, lying in a vertical plane containing the axis of the apron pivots, which ram also extends from one of said columns to the other. In such a machine, the ram, equipped with a forming mandrel along its bottom edge, is movable vertically, upwards to permit insertion of the workpiece, and downwards to clamp it in place upon the working surfaces of the aprons. The clamping position to which the ram is moved must be adjustable to suit the particular mandrel employed.

For certain types of operations the total travel of the clamping ram must be substantial, and yet the finallyadjusted clamping position must be quite accurate and must be accurately and firmly held as against the substantial upward pressures exerted through the workpiece by the working operations of the aprons therebeneath.

The present invention relates to the operation of the clamping ram, especially in machines such as briefly described above, and more particularly relates to the mechanism for effecting the movements and clamping action of the ram, inclusive of the means for establishing various clamping positions for the ram.

The principal object of the invention is to render the variation, the setting, and the maintenance of the clamping position of the ram, very simple and at the same time reliable.

Another object of the inventtion is to reduce undesired stresses upon and undesired deformations of the machine and the workpiece upon which it is operating.

A further object is to facilitate and speed up the operation of metal forming brake machines.

Still another object is to provide greater uniformity of pressure upon the clamping ram of such machines for the different positions over a given range of travel of the ram.

It is a further object of the invention to accomplish the above-stated objects by improved brake mechanism, and particularly by improvements in the mechanism for operating the ram, the mechanism for variably fixing the clamping position of the ram, the mechanism for indicating the desired ram stop adjustments, the mechanism for guiding and seating the ram; and parts embodied in or associated with those mechanisms.

How the foregoing and other objects, with attendant advantages, are attained by this invention will appear from the following description, with the accompanying drawings, of brake mechanism incorporating the presently preferred embodiment of the invention.

In the drawings:

FIGURE 1 is a front elevational view of a brake for forming plate or sheet workpieces, with the left-hand column structure of the frame of the machine shown in section to expose interior parts;

FIGURE 2 is a vertical cross section taken on the line 22 of FIGURE 1;

FIGURE 3 is an enlarged fragmentary vertical crosssection taken on the line 33 of FIGURE 1 with the cylinder appearing in elevation;

FIGURE 4 is a fragmentary enlarged plan section taken on the line 4-4 of FIGURE 2;

FIGURE 5 is an enlarged section taken approximately on the line 55 of FIGURE 1 illustrating adjustable stop mechanism associated with the clamping ram of the machine, a part of the ram being shown in a lowered position, in engagement with an aligning seat on a part of the stop mechanism;

FIGURE 6 is a plan section taken on the line 66 of FIGURE 5; and

FIGURE 7 is a vertical section taken on the line 7-7 of FIGURE 5.

In FIGURE 1, I have illustrated a brake of the type generally illustrated in my prior Patent 3,044,526, dated July 17, 1962, but embodying, in presently preferred form, the improvements of the present invention.

The machine, in general, comprises framing lying in a substantially vertical plane, including two upright end column structures 8 and 9, rigidly joined at the top by a horizontal frame structure 10, which may conveniently be formed of a pair of channel members (i.e. of U- section) extending nearly the full length of the machine, and joined at their ends to said column structures by suitable brackets 11, 11. Bottom horizontal framing, fragmentarily shown at 12 in FIGURE 2, rigidly joins the lower ends of the upright structures 8 and 9.

As seen in FIGURES 1 and 2, the machine incorporates a pair of aprons or

wings

13 and 14, extending substantially the length of the machine, which at their upper edges have reinforcing angle-

bars

15, 15, and carry wear-plates or forming-

blades

16, 16. The wings may be vertically stiffened, as by plates 14'. Each of the wing members is mounted, at each end, for vertical adjustment in a massive hinge body, the hinge bodies for the wing or apron 13, being shown at 17, and those for the apron 14 being shown at 18. These hinge bodies are mounted by interdigitating

knuckles

19 and 20 respectively, upon the pivots 21, the axis of which constitutes the axis about which the forming-blades 16 must move during the forming operations.

It will be observed from FIGURE 2, that, in the position of the parts there shown, the upper or working surfaces of the forming blades 16 are co-planar, and the upper edge of contact of these two surfaces is on the axis of the pivot pins 21. However, from the position shown in that figure, the

wings

13 and 14, and thus the forming

blades

16, 16 may be adjusted downwardly, eitherseparately or together, by means of the screw mechanism 22, worm wheels 23, and worms 24, one at each end of the adjusting shaft 25, in the manner illustrated and described more fully in my said prior patent, and for the purposes fully set forth therein. The rocking of the wing or

apron members

13, 14, and their associated parts hereinabove described, about the pivot means 21, may be effected, independently with respect to each of the wings, or conjointly, through controllable power means, such as the piston and

cylinder assemblies

26, 27, in the manner set out fully in said prior patent. It will be understood that the thickness of the sheet or plate to be worked upon, the use of a stepped configuration of workpiece, the type of forming operation being performed, and the configuration of the mandrel being used in the machine, are factors in the determination of the adjustments to be made in the positions of the forming assemblies (

wings

13 and 14 an associated parts including the blades 16) relative to the axis of the pivot pins 21. This need not be elaborated upon at this point, since the adjustments and ice ea operation of those assemblies may be carried out in the same manner as that which is fully disclosed in my said patent.

For co-operation with the mechanism just described, the machine comprises a mandrel-equipped clamping ram. This preferably comprises a pair of members, one being a heavy metal plate 28 of considerable vertical depth (as shown in FIGURES 1 and 2), extending from endto-end of the machine, and another being the mandrel 29, running along the bottom edge of the plate 28, and conveniently secured thereto by means of a rabbet or shoulder, and a retaining plate 31 having any suitable fastening means (not shown).

The mandrel 29 herein illustrated comes almost to a knife edge, as shown at 32, which is particularly suitable for the forming of sharp bends. Bends of various radii, however, are of course obtainable by applying different mandrels to the clamping ram, as will be apparent from inspection of my said prior patent, and particularly FIG- URES 15 to 27 thereof, which illustrate the use of a variety of mandrels in forming various bends, in several different forms of sheet or plate members.

The axis of the radius of curvature of the mandrel employed, the axis of the curvature imposed upon the workpiece, and the axis of the pivots 21 for the swinging of the wings must all be substantially coincident, as is fully brought out in my said prior patent. Accordingly, the clamping position of the ram must be adjustable to suit the configuration of the mandrel which is being employed. Accurately adjustable fixing of the downward limit of the clamping ram must accordingly be had. At the same time, ay such bottom limit of the movement of the ram must be rigidly held as against the upward thrusts imposed by the action of the working surfaces 16 (on the top of the wings) when they are bending the workpiece around the curved edge of the mandrel. It is also important that the necessary adjustments may be easily, quickly and accurately made, and that the motion of the clamping ram from an upper position (providing ample room for inserting, manipulating, and removing the workpieces) downwardly to the selected clamping position should be rapid, and yet positively limited so as to avoid damage to the machine or the workpieces. The features now to be described are constructed and arranged to accomplish these and other advantageous purposes.

At each end of the main plate 28 of the ram, there is an extended tongue 28a, as seen in most of the figures of the drawings. One tongue extends into each of the re spective columns 8 and 9 of the framing, and each tongue is coupled by a pivot 33 and clevis 34 to the threaded end 35 of the piston rod of piston 36 in a hydraulic cylinder 37, which is in turn mounted by trunnions 38 in bosses 39 fastened to the column structure of the framing. Upper and lower

fluid pressure lines

41, 42 serve for the admission an exhaust of hydraulic or other fluid under pressure for the raising and lowering of the clamping ram. (The fluid-pressure system to be coupled to the

lines

41 and 42, and the electrical control system therefor, if such be used, are not illustrated herein, as they may follow the form shown in my said patent, or a suitable modification thereof, or may be in the form of some other available system.)

In the raising and lowering of the clamping ram, the tongues 28a are guided, so as to hold the ram plate 28 in its intended vertical plane, by guiding means such as shown in FIGURE 4, comprising wear strips 43 fixed to the member 28a, anti-friction guide members 44, and adjusting screws 45 held in lugs 46 fastened on the column structure of the framing. Besides allowing for vertical motion of the ram, this assembly also permits endwise and angular motions of the ram, within the vertical plane. The extent of these motions, however, is limited by the clearance between the arcuate end surfaces 47 of the ram plate extensions 28a and the bearing plates 48 fixed within the upright columns 8 and 9. The capability for slight endwise and rocking motions of the ram in the vertical plane is desirable, especially to accommodate certain differences in adjustment of the stop mechanisms at the two ends of the machine, which differences may from time-totime be required because of differences in thickness of one end of a workpiece compared with the opposite end.

Turning now to the stop mechanism, the essential parts of this and of the associated indicator devices, will be seen in FIGURES 1, 2, 5, 6 and 7. For the most part, the description will refer to the stop mechanism and indicator at the right-hand end of the machine in FIGURE 1, although a duplicate mechanism is utilized at the left-hand end.

A fixed block 49 is secured to the tension members constituting the main walls of the column 9, and also secured by several compression members such as shown at 51, 52 to the pivot assembly 21. On top of block 49 is a fixed seat 53 having a guideway 54 in its upper surface, to receive a movable wedge member 55. The sloping upper surface 56 of this wedge member engages the sloping lower surface 57 of a second wedge member 58, which is fixed as against horizontal movement, but is guided for vertical movement, by means of the fixed vertical pins 59.

Wedge member 55 is horizontally moved to various positions, by means of the screw 61 which is threaded into the wedge member. When the ram is raised, the screw 61 may readily be adjusted by hand, from outside of the column 9, by means of the knob 62, which is fixed on the outer end of screw 61. A retaining ring 63 is fixed on the screw, at the inner side of the associated wall of the column 9. Thus, the screw 61 has no appreciable axial motion, and when it is turned by knob 62 the wedge 55 must move backward or forward; which can be done when the ram is raised.

On top of the upper wedge member 58 is a concave seat 64, receiving a convex alignment member 65, having a flat upper surface 66. The bottom face of the extension or tongue 28a of the main ram plate 28 seats on the surface 66, when the clamping ram moves down. A firm and square seating will be assured, no matter what may be the adjustment of the two stops at the opposite ends of the ram, since the curved mating surfaces of the

parts

58 and 65 will accommodate any angularity of the ram in the vertical plane, due to such difference in adjustment of the two stops. Accordingly, the concavoconvex seats need not be spherical, but may be cylindrical, as shown, with the axis of the cylinder extending transversely to the general plane of the ram. For similar reasons, the axis of the pivot 38 for the operating cylinder 37, and the axis of the pin 33 securing the piston to the ram, are made parallel to each other and to the axis of the cylindrical seating surfaces.

It will now be apparent that by a proper selection of the angle of the wedge surfaces 56 and 57 and of the travel of the wedge member 55, there may be provided a range of adjustment of the clamping position of the ram such as will take care of the range of bending radii for which the machine is to be adapted (as by the substitution of different mandrels 29). For the quick preliminary setting of the clamping position, there is provided a direct reading indicator at each of the two adjustable stop assemblies. This is clearly shown in FIGURES 5 and 6. On the column 9 is pivotally mounted an indicating pointer 67, pivoted at 68 and having an extension 69 engaging the pin 70 on wedge member 58. The right-hand end of pointer 67 (as seen in FIGURE 5) is heavier than the portion 69, so that the latter is maintained in contact with pin 70. The tip 71 of the pointer moves in proximity to a scale plate 72 which is fixed on the frame. This plate carries indicia 73, which may be graduated to give a direct reading in fractions of an inch, representing the dimension of the radius of curvature of the mandrel which is to be employed. When initially setting the adjustable stops, for use with a particular mandrel, the wedge at each end of the machine may be first so set that the pointed indicates a radius such as will provide a slight clearance with respect to the workpiece (after the radial adjustment of the Working surfaces 16 of the aprons has been made). Thereafter, with a workpiece in place in the machine, and the clamping ram brought down against the stop seats 66, a further, fine, adjustment may be made by the same knurled knobs 62 used for the initial setting of the wedgesuntil the working surface of the mandrel has made a line contact with the upper surface of the workpiece. In this way, the exact clamping action desired is quickly obtained, with a minimum risk of damage to the workpiece or strain upon the machine. Identical workpieces can then be run through the machine, one after another, with little or no further adjustment. A firm seating of the tongues 28a of the clamping ram upon the fixed stops is assured, and these stops take the major pressure from the cylinders 37.

From the foregoing description, it is believed that it will be apparent how the objects and advantages hereinbefore set out are obtained.

I claim:

1. In a brake, for forming plate or sheet workpieces, having a frame and a mandrel-equipped clamping ram adapted to cooperate with a working surface of a pivotally-mounted working member in the clamping and forming of a workpiece, and wherein the ram is movable so as to dispose the forming axis of the mandrel on, or at a distance from, the pivot axis of said pivotallymounted working member, the combination, with said ram, of mechanism for moving and holding it comprising a movable stop positioned to limit the stroke of the ram relative to the frame and having an adjustable wedge device for variably setting it to determine the clamping position of the ram, and a fluid-pressure device having a cylinder element and a piston element, one of which elements acts against the frame and the other acts against and moves with the ram so as to urge the ram against the stop and hold it there, by fluid pressure, in its workpiece clamping position.

2. In a brake, for forming plate or sheet workpieces, having a frame and a mandrel-equipped clamping ram adapted to cooperate with a working surface of a pivotally-mounted working member in the clamping and forming of a workpiece, and wherein the ram is movable so as to dispose the forming axis of the mandrel on, or at a distance from, the pivot axis of said pivotallymounted working member, the combination, with said ram, of mechanism for moving and holding it comprising a movable stop positioned to limit the stroke of the ram relative to the frame and having an adjustable wedge device for variably setting it to determine the clamping position of the ram, and a fluid-pressure device having a cylinder element and a piston element, one of which elements acts against the frame and the other acts against and moves with the ram so as to urge the ram against the stop and hold it there, by fluid pressure, in its workpiece clamping position, and means for accommodating angular changes of position of the clamping ram relative to the frame.

3. The construction of claim 2 wherein the last-named means comprises a convex bearing member and a concave seat therefor.

4. The construction of claim 2 wherein the last-named means comprises a pivotal mounting for one element of the cylinder-and-pi'ston device.

5. In a brake, for forming plate or sheet workpieces, having a frame and a mandrel-equipped clamping ram adapted to cooperate with a working surface of a pivotallymounted working member in the clamping and forming of a workpiece, and wherein the ram is movable so as to dispose the forming axis of the mandrel on, or at a distance from, the pivot axis of said pivotally-mounted working member, the combination, with said ram, of

mechanism for moving and holding it comprising, stop means for the ram for limiting the stroke of the ram relative to the frame, said stop means being adjustable to set selectable locations for the clamping position of the ram, and mechanism adapted to move said ram to and hold it against said stop means, comprising a fluid-pressure device having a cylinder element and a piston element, one of which elements acts against the frame and the other acts against and moves with the ram so as to urge the ram against the stop and hold it there, by fluid pressure, in its workpiece clamping position.

6. In a brake, for forming plate or sheet workpieces, having a frame and a mandrel-equipped clamping ram adapted to cooperate with a working surface of a pivotallymounted working member in the clamping and forming of a workpiece, and wherein the ram is movable so as to dispose the forming axis of the mandrel on, or at a distance from, the pivot axis of said pivotally-mounted working member, the combination, with said ram, of mechanism for moving and holding it comprising, stop means for the ram for limiting the stroke of the ram relative to the frame, said stop means being adjustable to set selectable locations for the clamping position of the ram, and mechanism adapted to move said ram to and hold it against said stop means, comprising a fluid-pressure device having a cylinder element and a piston element, one of which elements acts against the frame and the other acts against and moves with the ram so as to urge the ram against the stop and hold it there, by fluid pressure, in its workpiece clamping position, and a scale device associated with the stop means so that the adjustment of the latter gives a direct indication of ram clamping position relative to the pivot axis of the working member.

7. The construction of claim 6 wherein the indicator provides a zero reading when the stop device is adjacent its uppermost normal operating position.

8. The construction of claim 5, wherein the mechanism recited is duplicated at each end of the brake.

9. In a brake, for forming plate or sheet workpieces, having a frame and a mandrel-equipped clamping ram adapted to cooperate with a working surface of a pivotally-mounted working member in the clamping and forming of a workpiece, and wherein the ram comprises an elongated member lying in a generally vertical plane and having its ends extended to regions adjacent to a pair of vertical columns of the frame, and said ram being movable in said generally vertical plane as as to dispose the forming axis of the mandrel on, or at a distance from the pivot axis of said pivotally-mounted working member, the combination of power means for raising and lowering the ram, a device for separately setting the lower limit of motion of each end of the ram, with respect to the frame, and adjustable-angle seating means adapted to accommodate different angularities of the ram accompanying the variations in setting of the limits of motion at the two ends of the ram.

10. In a brake, for forming plate or sheet workpieces, having a frame and a mandrel-equipped clamping ram adapted to cooperate with a working surface of a pivotally-mounted working member in the clamping and forming of a workpiece, and wherein the ram comprises an elongated member lying in a generally vertical plane and having its ends extended to regions adjacent to a pair of vertical columns of the frame, and said ram being movable in said generally vertical plane so as to dispose the forming axis of the mandrel on, or at a distance from, the pivot axis of said pivotally-mounted working member, the combination of power means for raising and lowering the ram, a device for separately setting the lower limit of motion of each end of the ram with respect to the frame, and guideways for the ram holding it in said generally vertical plane and constructed and arranged to permit it to be moved vertically and angularly in a vertical plane.

11. The construction of claim 10, having means providing for a limited endwise motion of the ram.

12. The construction of claim 10, wherein the ends of the ram have surfaces curved about axes extending transversely of the ram, and the frame has guideways cooperating with said curved surfaces.

13. In a brake, for forming plate or sheet workpieces, having a frame and a mandrel-equipped clamping ram adapted to cooperate with a working surface of a pivotally-mounted working member in the clamping and forming of a workpiece, and wherein the ram comprises an elongated member lying in a generally vertical plane and having its ends extended to regions adjacent to a pair of vertical columns of the frame, and said ram being movable in said generally vertical plane so as to dispose the forming axis of the mandrel on, or at a distance from, the pivot axis of said pivotally-mounted working memher, the combination of power means for raising and lowering the ram, a device for separately setting the lower limit of motion of each end of the ram with respect to the frame, the power means comprising a piston-andcylinder assembly at each end of the ram, and a connection from each said assembly to the associated end of the ram including pivot means with a pivot axis extending transversely of the vertical plane of the ram.

References Cited by the Examiner UNITED STATES PATENTS CHARLES W. LANHAM, Primary Examiner.

R. D. GREFE, Assistant Examiner.

Claims

1. IN A BRAKE, FOR FORMING PLATE OR SHEET WORKPIECES, HAVING A FRAME AND A MANDREL-EQUIPPED CLAMPLING RAM ADAPTED TO COOPERATE WITH A WORKING SURFACE OF A PIVOTALLYMOUNTED WORKING MEMBER IN THE CLAMPING AND FORMING OF A WORKPIECE, AND WHEREIN THE RAM IS MOVABLE SO AS TO DISPOSE THE FORMING AXIS OF THE MANDREL ON, OR AT A DISTANCE FROM, THE PIVOT AXIS OF SAID PIVOTALLY-MOUNTED WORKING MEMBER, THE COMBINATION, WITH SAID RAM, OF MECHANISM FOR MOVING AND HOLDING IT COMPRISING A MOVABLE STOP POSITIONED TO LIMIT THE STROKE OF THE RAM RELATIVE TO THE FRAME AND HAVING AN ADJUSTABLE WEDGE DEVICE FOR VARIABLY SETTING IT TO DETERMINE THE CLAMPING POSITION OF THE RAM, AND A FLUID-PRESSURE DEVICE HAVING A CYLINDER ELEMENT AND A PISTON ELEMENT, ONE OF WHICH ELEMENTS ACTS AGAINST THE FRAME AND THE OTHER ACTS AGAINST AND MOVES WITH THE RAM SO AS TO URGE THE RAM AGAINST THE STOP AND HOLD IT THERE, BY FLUID PRESSURE, IN ITS WORKPIECE CLAMPING POSITION.