US3459020A

US3459020A - Plate-bending roll for steel plates and the like

Info

Publication number: US3459020A
Application number: US429362A
Authority: US
Inventors: Toshimitsu Morita; Masuo Taki; Maomi Kaneda; Sakae Kohno
Original assignee: Hitachi Zosen Corp
Current assignee: Hitachi Zosen Corp
Priority date: 1965-02-01
Filing date: 1965-02-01
Publication date: 1969-08-05
Anticipated expiration: 1986-08-05

Description

A 1969 TOSHIMITSU MORITA ETAL 3,459,020

PLATE-BENDING ROLL FOR STEEL PLATES AND THE LIKE Filed Feb. 1, 1965 2 Sheets-Sheet 1 mv TORS TOS IMITSUMORITA- AS 0 r, MHO W KANEg A nno' 17K EKQfiNO Aug. 5, 1969 TOSHIMITSU MORITA ETAL I PLATE'BENDING ROLL FOR STEEL PLATES AND THE LIKE Filed Feb. 1, 1965 2 Sheets-Sheet 2 m wm United States Patent US. Cl. 72-22 3 Claims ABSTRACT OF THE DISCLOSURE The present invention relates to a plate-bending roll for steel plates and the like hereinafter referred to as the workpiece. More particularly the present invention relates to a device for shaping and controlling processes for the purpose of automatically manufacturing cylindrical or tubular bodies of a cross-sectional shape composed of more than two continuous arcs.

Background of the invention In the plate-bending roll for steel plates and the like the present invention relates, furthermore particularly, to a device for automatically controlling the bending process onto the leading edge and the trailing edge of workpieces in manufacturing cylindrical or tubular materials composed of, as aforementioned, more than two continuous arcs by bending flat plates.

A conventional steel-plate-bending roll is composed of three or four rolls arranged in a pinch-form or pyramidally; in the case of subjecting to a shaping process pipes having a cross section composed of a group of curved surfaces with different curvatures, such as an elliptical form, it has been a common practice to prepare a gauge of a specific cross section, to set the said gauge successively to a steel plate or the liked worked piece throughout, or partially of, the whole of the plate while confirming the curvatures thereof, and thus to accomplish the bending process. Consequently the said method used not only requires very much time and also to be precise by no means, so as to be quite inefiicient practically as it has ever been.

In the bending process of steel plates and the like by plate-bending roll, the bending work on the both ends of a workpiece is extremely important as it will control the quality and precision of the product. Accordingly the said end-bending work has heretofore been carried out very carefully and in a full time through many a step of process.

Further it has become so important a matter that such a costly device as a press used solely for end bending is called for these days. Hence the present invention has been directed so as to improve as will be disclosed in the present specification in view of the remarkable defects in the foregoing and to eliminate all of them once for all.

In other words, the features of the present invention reside in that it consists of workpiece delivery rolls which rotate mutually reversely and bending rolls which elevates on an axis having a desired angle with the axis of the said delivery rolls; that the delivery amount of a workpiece and the elevation amount of the bending rolls are automatically controlled; and that any specified bending process may be carried out by setting automatically the curvature of a desired cross section composed of one or more continuous arcs of the workpiece according to the relativity of the said delivery amount with the elevation amount.

Description What is characterized by the present invention lies with the fact that the automatic control of the aforementioned delivery amount of a worked piece and the elevation amount of the bending rolls is effected by means of a limit switch group for starting the delivery rolls as well as the bending rolls which are provided so as to work successively following up (synchronously with) the movement of the delivery rolls and the bending rolls and so as to freely regulate the operational periods; and that the setting of each curvature in conformity with the cross section of a worked piece may be carried out by freely regulating the operational periods of the said limit switch group.

Other features of the present invention reside in that: the said automatic control system for the delivery amount of a worked piece and the elevational amount of the bending rolls is further provided with a group of limit switches for starting the drive source of the bendin rolls variable of the operational positions (periods) so as to follow up the delivery of the worked piece and successively operate; further provision is made in a manner such that a group of limit switches for controlling the elevation of the bending rolls variable of the operational positions (periods) is operated synchronously with the elevation of the bending rolls; by these provisions, the elevational control of the bending rolls that have been so arranged as to be driven from the drive source through a stepless speed-change gear may be carried out, and thus a specified shape of worked pieces may be automatically formed by determining the curvature of each arc of a cross sectional shape composed of one or more continuous arcs.

Another feature of the present invention is found to lie in the mechanism that the elevation as Well as the end bending of the front roll used solely for the end bending of worked pieces may be automatically carried out, and, after the end bending is completely finished, the ordinary bending work thereupon may automatically set out.

Now, as regards the foregoing numerous features of the present invention, preferred exemplary embodiments of the same will be illustrated in details with reference to the drawings, in which:

FIG. 1 is a partial schematic view of the apparatus for the bending of a workpiece into an elliptical formation showing a preferred example of the present invention;

FIG. 2 and FIG. 3 are illustrative views of the bending of a work piece by the present apparatus;

FIG. 4 is a partial plan view showing a modified form of the automatic control system for operation of the present invention;

FIG. 5 is an enlarged detail view taken on the line V-V of FIG. 4; and

FIG. 6 is an illustrative view showing the relationship between the rolls and the limit switches of the system of FIG. 4.

The object of the present invention will be clearly understood from the following detailed disclosure with ref erence to the appended drawings, in which:

In FIG. 1 the delivery rolls for the work piece 3 consist of the upper roll 1 and the lower roll 2. The said

rolls

1 and 2 rotate in opposite directions and at the same peripheral velocity upon being driven by a gear group housed within the housing 4. Thus the work piece 3 is moved when the device is operated.

The rear roll 5 is so arranged, as is shown in FIGS. 2 and 3, that it elevates up and down in the direction of the straight line A-B forming a specified angle to the straight line A-A and that front roll 6, used solely for the end bending operation for the work piece 3, elevates in the direction of the straight line C-C forming a specified angle against the straight line A-A and is fitted on the opposite side of said rear roll 5. 7 is the elevation shaft of rear roll 5 and has one end secured to the rear roll 5 and its other end supported by the elevator 8. Said shaft 7 is driven by the driving shaft 11 connected through the stepless speed-change gear 10 to the drive source 9, and is elevated in the direction of the straight line A-B. The driving shaft 11 is provided with the screw portion 12, which in threaded engagement with the cam for operating the upper-limit switch 13 and the lower-limit switch 14 of the rear roll 5. Said cam 15 is provided with a guide piece (not shown in the drawings) so that it may move along the axial direction of the driving shaft 11 upon the rotation of said driving shaft. The said upper and lower-

limit switches

13 and 14 are mounted on the adjusting screw shaft 16 for changing their positions in relation with the position of said cam 15 so as to freely regulate the upper-limit or lower-limit operation positions or periods respectively, thus making it possible to provide any kind of shaping of the work piece such as elliptical forms and the like.

17 and 18 are limited switches for starting upward the rear-roll

elevation drive source

9 and 19 and 20 are limit switches for starting downward the rear-roll elevation drive source 9. These limit switches have been mounted on the adjusting

screw shafts

21 and 22 so as to have the respective operational positions or periods freely adjustable and further have been arranged in parallel with the screw shaft 24 of the cam 23 for operating said limit switch group. Both ends of the rotation shaft 24 are connected by way of the

clutches

25 and 26, respectively, with the driving shaft 27 extending from the housing 4 and with the transmission shaft 29 of the drive source 28 for the zero-point return of the cam 23.

Further, 30 is the drive source for the front roll 6 through the elevator 32 and the elevation shaft 31 which has one end fixed to the front roll 6 and is driven by the driving shaft 34 from the said drive source 30 through the gear box 33 or this may be a stepless speed-change gear. Said driving shaft 34 is provided with the screw portion 35, which is in threaded engagement with the cam 38 for the elevational starting of the front roll as well as the operation of the

control limit switches

36 and 37 of the

delivery rolls

1 and 2, and said limit switches are mounted on the adjusting screw shaft 39 so as to make their respective positions variable relative to the positions of the cam 38. In addition, the cam 38 has been constrained by a guide piece (not shown in the drawings) so as to move along the axial direction of the driving shaft 34.

40a is a limit switch which is for simultaneously carrying out the descent step of the front roll 6 and is devised so as to operate according to the specified delivery rate of work piece 3 and the stopping of the upper and

lower delivery rolls

1 and 2 and also the throw-in of the clutch 25. 40b is a projection on the workpiece for operating the limit switch 40a and is secured to the position corresponding to the end-bending length on one side of the work piece 3.

Now the operational steps will be described for the shaping of a tubular material having an approximate-elliptical cross section by a device in accordance with the present mvention:

In the first plate the

limit switches

13, 14, 17, 18, 19, 20, 36, 37, and 40 must have been adjusted to positions where a specified cross-sectional form of work piece Will be shaped. An edge of a work piece 3 is placed by hydraulic means or some other mechanism (not shown) between the

delivery rolls

1 and 2 in a securely pinched condition, and the drive source 30 of the front roll 6 is started by a push-button control so as to begin the bending work. Thereupon the front roll 6 starts to elevate and operates to bend the workpiece as is shown in FIG. 3, and it stops elevating when the cam 38 shifts as the driving shaft 34 rotates, so that the limit switch 36 is placed in action, and

at the same time the upper and

lower delivery rolls

1 and 2 are operated so that the work piece 3 is delivered while also being bent. And when the projection 40b puts the limit switch 40a into action, the

delivery rolls

1 and 2 come to a stop and the end-bending work thus come to an end.

Whereas, when the front roll 6 starts to descent at the same time the

delivery rolls

1 and 2 come to a stop and the cam 38 puts the limit switch 37 in action, the front roll 6 will come to a stop and also the rotation shaft 24 will start to rotate starting the upper and

lower delivery rolls

1 and 2 at the same time the clutch 25 is thrown in, and by the said starting will advance of the process into the succeeding main stage; and in addition, the clutch 26 is opened. Accordingly, the cam 23 will shift as the rotation shaft 24 rotates, so as to activate the limit switch 17 and will start the drive source 9 so as to elevate the rear roll 5. At this instant the workpiece 3 is delivered while also being bent, and the smooth shaping thereof may be achieved on the connection of the greaterdiameter portion and the smaller-diameter portion of an approximate ellipse. The cam 15 will then move rightward as the driving shaft 12 rotates and said cam 15 will put the limit switch 13 in action, when the rear roll 5 comes to a stop and arcs of a certain curvature are shaped on account of the delivery of the workpiece 3 by the rotation of the

delivery rolls

1 and 2.

The cam 23 thenceforward puts the limit switch 19 in action, when a reverse starting of the drive source 9 is carried out and the rear roll 5 starts to lower, so that the formation of a next connection of the smaller-diameter portion and the greater-diameter portion begins. Then the rear roll 5 stops its descent upon operation of the limit switch 14 by the movement of the cam 15 to the left. For forming the connection turns in the shaping of an arciform portion of a certain curvature; the limit switch 18 is activated by the cam 23 so as to start the elevation of the rear roll 5 and again a next arciform shaping of the connection of the greater diameter and the smaller diameter comes into effect; the cam 15 again shifts to the right so as to put the limit switch 13 in action, when the rear roll 5 comes to a stop and the shaping of a next arc of a certain curvature takes its turn; the cam 23 activates the limit switch 20 so that the rear roll 5 again is lowered, thus the shaping of the last arciform connection of the smaller diameter and the greater diameter is effectuated. When the cam' 15 shifts to the left and the limit switch 14 is activated, the shaping of the last arc of a certain curvature is carried out by delivery of the workpiece 3 so as to complete the tubular formation of an approximate elliptical profile; and the cam 23 reaching the right end, a stop switch (not shown in the drawings) of the

delivery rolls

1 and 2 is operated so as to stop the delivery rolls, while the cam 23 is returned to its starting position by opening the clutch 25 and b throwing-in the clutch 26 as well as by starting the drive source for zero-point return 28. In this way, each stage of the process is finished automatically and any specified cross-sectional shape is obtainable subsequent to the starting of the bending process of elliptical formation primarily by means of push-button control.

Furthermore, the end-bending work of any desired curvature may be possibe, automatically and reliably, if and when the setting of the respective operational positions of the

limit switches

36, 37, and 40 has been preliminarily carried out by end-bending dimension, and the like in accordance with the cross-sectional curvature of the workpiece. Consequently it is needless to say that the device of the present invention is fitted to what is composed of the three rolls of the upper and lower delivery rolls and the rear roll in case the end-bending operation is carried out by a different machine used exclusively therefor, and it is as well possible that the front roll 6 can be manually operated as has been conventionally done, even by a bending machine composed of four rolls, so that there is that a wide range of use of the present device.

In the present invention, moreover, it is possible to choose an elevational velocity of the bending rolls freely and steplessly so that smooth curved surfaces may be shaped without giving rise to a collapsedportion by virtue of having a stepless speed-change gear interposed between the driving shaft and the drive source of the elevator for the bending rolls that is the front roll and rear roll.

Now the second embodiment of the present invention will be described in reference to FIGS. 4, 5 and 6 as follows:

The delivery rolls for the workpieces 3 is entirely similar to that of the foregoing first embodiment. That is to say the upper roll 1 and the lower roll 2 are so arranged that the rotation force is transmitted by a gear group located within the housing 4 and they rotate mutually in the opposite directions and at the same peripheral velocity so that the workpiece 3 may be conveyed. The bending roll 5b is also so arranged as to elevate in the direction of the straight line AB forming a specific angle to the straight line AA as shown in FIG. 6 and is moved and controlled by a hydraulic means or the like so that work piece may be bent into a cylinder or pipe of a specified cross-sectional shape. It is so devised that the rotational control of the upper roll 1 and the lower roll 2 or the control of the speed of the delivery of the workpiece 3 is carried out by means of the roll-driving control device 41, and the control of elevation of the bending roll 5b is as well carried out through said control device 41 by controlling a hydraulic circuit (not shown in the drawings) for driving the bending roll 5b.

The aforementioned control device 41 is so composed that the

limit switches

47, 48, 49, and 50 are activated by means of the cams 43, 44, 45 and 46 having a specified shape and secured to the cam shaft 42.

The limit switches 47, 48, 49 and 5t), furthermore, are so arranged that they are respectively secured to the

larger bevel gear

51, 52, 53, and 54 and are capable of having their positions freely adjusted relative to the earns 43, 44, 45, and 46 by means of the

handles

59, 60, 61 and 62 for adjusting the limit switch positions mounted respectively onto each shaft of the

smaller bevel gears

55, 56, 57, and 58 in mesh with said larger bevel gears. In other words, by changing the positions against the cams 43-46 for the limit switches 47-50, a rotational stop or lowspeed operation of the

rolls

1 and 2 is elfectuated at the same time the hydraulic circuit of the bending roll 5]; is opened in the direction of elevation or descent and thus activated so as to start to elevate or lower the bending roll 5b and the changeover from elevation to descent may also be thereby carried out. It is further so devised that the both ends of the bending roll 5b are provided with the limit switches 63, 64, 65 and 66 for stopping the bending roll 5b as well as for starting the

rolls

1 and 2, which may be activated following the movement of the bending roll 5b. The said limit switches 63-66 may be activated directly or indirectly by the bending roll 5b. Said limit switches 47-50 and 63-66 are capable for forming cylinders or pipes having cross sections of numerous aggregated curved surfaces by providing any desired number of them. The number of the cams 43-46 to be provided also may be as many as there are limit switches 47-50, and the shapes may as well be determined freely so as to be adaptable to varied objectives. The driving of the cam shaft 42 of the control device 41 is carried out through the gears 67 and 68 secured to the roll 2, the stepless speed change gear 69 and the zero-point returning device 70 of the said control means 41.

And the control device 41 is regulated to zero point from both sides by the zero-

point returning devices

70 and 71 and the home point of the cams 43-50 is so arranged as to be precisely set.

The forming operation of a tubular product having an approximate elliptical cross-sectional contour by means of the aforementioned device is explained a follows:

Firstly the leading edge of a work piece 3 is inserted between the

rolls

1 and 2 and the zero-point adjustment of the automatic control system is carried out. Thereafter the regulation handles 59-62 are rotated and thereby the operational position of each of the limit switches 47-50 is set so a to correspond to the arciform length of the curved surface of a specified cross section of the work piece with the home point of each of the cams 43-46 as reference. Further the rotation number of the cam shaft 42 is regulated by means of the stepless speed-change gear 70 and the operational positions of the limit switches 63-66 are also regulated and thus the setting for a specified cross-sectional shape is finished. With the start of rotation of the

rolls

1 and 2, the work piece 3 is delivered forth onto the bending roll 5b as far as the required distance when the cam 43 puts the limit switch 47 in action so as to make the

rolls

1 and 2 stop or lower in speed, so that the bending roll 5b starts to elevate and it will come to a stop after, for instance, the limit switch 65 has been activated. A curved surface, one arc, of the work piece 3 will be formed during this process. With the stop of the bending roll 5b, the

rolls

1 and 2 come into an ordinary delivery speed from the halt or lower-speed condition to carry out the delivery of the work piece 3, activating successively the limit switches 48-50 and 64-66, thus ending in the completion of the bending process.

By virtue of the aformentioned operation, any finished shape of the cross-section of work pieces 3, such as true circle, approximate ellipse and the like, even any profile consisting of continuous arcs, may be preferred and determined freely by properly setting the operational positions of the limit switches of any desired number provided for specified respective objectives and further by regulatin the rotation speed of the cam shaft 42 through the stepless peed-change gear 70. Accordingly, cylinders or pipes of any desired cross-sectional shapes may be formed automatically by setting, as the foregoing descrip tion has said, the shapes of cross-section preliminarily.

Such being the present invention, the operation of the present device is capable of manufacturing, automatically, articles with high precision having exact and smooth curved surfaces with any cross-sectional shape composed of continuou arcs. Said device as a whole being simple and low in cost and almost free from trouble and therefore very economical, so that it will contribute tremendously to the reduction of production costs, to say nothing of its working eificiency, and thus much can be expected from its availability.

We claim:

1. In a plate-bending roll for steel plates and the like comprising a pair of superposed workpiece delivery rolls, means for rotating said rolls in opposite directions, a front roll, a rear roll, means for moving said front and rear rolls each on a straight line having a specified angle to the straight line connecting both axes of said delivery rolls, and a workpiece end-bending control device characterized by an elevating shaft supporting said front roll, an elevator for elevating said elevating shaft, a driven shaft for operating said elevator and having a threaded portion, a cam in threaded engagement with said driven shaft threaded portion, adjustable limit switches controlling said rotating means and said driven shaft for elevating and stopping said front roll and starting said delivery rolls, further adjustable limit switches also controlling said rotating means and said driven shaft for stopping the descent of said front roll and starting said delivery rolls and positioned in parallel with said driven shaft so as to enable their setting positions to be freely adjusted, both limitswitch groups being arranged so as to be activated upon the moving of said cam along said driven shaft upon the rotation of said driven shaft, and limit switches positioned alongside the workpiece for temporarily stopping the rotating means for said delivery rolls and arranged so as to be activated according to any set initial portion of the workpiece.

2. A plate-bending roll for steel plates and the like comprising a pair of superposed workpiece delivery rolls, means for rotating said rolls in opposite directions, bending rolls, means for elevating said bending rolls each on a straight line having a specified angle to the straight line connecting the both axes of the said delivery rolls, adjustable means for automatically controlling the initial amount of delivery of the workpiece as well as the amount of elevation of the bending rolls, and automatically carrying out a specified series of bending operations on the workpiece, by presetting the desired curvature of each of the one or more continuous arcs, by relating amount of delivery of the workpiece to said amount of elevation.

3. In a plate-bending roll for steel plates and the like so devised as to automatically carry out specified bending of a workpiece by controlling the delivery amount of the workpiece and the amount of elevation of bending rolls, an automatic control system for carrying out this operation comprising a pair of superposed workpiece delivery rolls, means for rotating said rolls in opposite directions, bending rolls, means for elevating said bending rolls on a straight line having a desired angle to the straight line connecting both axes of said delivery rolls, a limit switch group for controlling said delivery rolls and said bending rolls adjustably mounted so as to have their respective operational positions freely adjustable, said limit switch group being arranged so as to be successively activated synchronously with the movement of said delivery rolls, and determining the curvature of each arc of a cross section, composed of one or more continuous arcs of the workpiece by regulating the operational positions of said limit switch group.

References Cited UNITED STATES PATENTS 2,038,305 4/1936 Mikaelson 72-134 2,742,078 4/1956 Williams 72-171 2,995,171 8/1961 Hausler 72171 FOREIGN PATENTS 1,0783,425 1/1960 Germany 20 CHARLES W. LANHAM, Primary Examiner A. L. HAVIS, Assistant Examiner