US3048213A - Machine and method of forming bands - Google Patents

Description

1962 R. DISTEL ETAL 3,048,213

FORMING BANDS Aug. 7, 1962 R. DISTEL ETAL MACHINE AND METHOD OF FORMING BANDS 3 Sheets-Sheet 2 Filed July 6, 1959 INVENTOR.

RICHARD DISTEL BY CHARLES F. HAUTAU ATTORNEY.

Aug. 7, 1962 R. DISTEL ETAL 3,048,213

MACHINE AND METHOD OF FORMING BANDS Filed July 6, 1959 3 Sheets-Sheet 3 ATTORNEY This invention relates to a method of forming circul-ar bands from sheet metal and to machinery for practicing this method. More particularly it relates to a method and machinery for forming circular brake bands.

Automatic transmissions usedon many contemporary vehicles incorporate circular bands of sheet metal which are coated with a high friction material on their interior surfaces and act as brake bands. In certain types of brakes it is desirable that the band form an are somewhat smaller than a complete circle. The need for the band being absolutely circular in both instances is apparent, since it must mate with a circular member (brake drum) which has a friction coating on its outer surface. Any

irregularities in the circular shape of the band will pro-.

duce greater wear in particular spots and greatly shorten the life of the band.

The present invention contemplates a method of forming circular brake bands in an economical manner from sheet steel. It also contemplates machinery for practicing this method.

In one embodiment of the invention, which will subsequently be described in detail, the band is formed from a strip of steel by two rolling operations. In the first operation one end of a strip of steel of the proper dimensions is pushed through sets of rollers which are adjusted so as to produce a circular bend which has a slightly larger diameter than the desired finished band. This circular bend is continued through something less than 360 degrees of arc. The bent section is then cut oif from the main strip along a line transverse to the axis of the strip at a point adjacent to where the bend commences. The partially formed band is then inserted in a second set of rollers which are powered .so as to causethe band it brace int to be rotated through them and rebent so as to slightly decrease the diameter ends of the band to meet so that a complete circular band is formed.

It has been determined that it is initially necessary to form the circular band by pushing a strip through passive rolls so that the exact measurement of the length of the material incorporated in the band may be made. Rolling the band to something less than a complete circular arc allows a cut-off to be made without disturbing the circularity of the band. If the band had been formed into a complete circle from a predetermined length of steel strip it would be extremely difficult to avoid fiattening its ends. Similarly, if it were necessary to cut off the band before inserting it into the roll, expensive ma terial handling techniques would be necessary.

The machine may be considered as consisting of four sections. The first section, generally indicated at 16, received an elongated strip 12 of sheet metal from a coil or similar supply source (not shown). is operative to straighten the strip 12 through a series of rolls and to feed a precisely measured length of the strip into a passive roll section, generally indicated at 14. The passive roll section 14 forms the strip 12 into an incomplete -(preferably approximately 320 degrees) circular section having a radius greater than that of the desired finished roll. The passive roll section 14 also provides a cut-oil device which separates the partially formed band from the strip 12 and delivers it to the poweredroll section of the machine, generally indicated at 16, by means of a delivery chute 18. The section 16 includes means for properly orienting the partially formed band, for feeding the band to a series of powered rolls, and for rerolling The section .10

the partially formed hands into a complete circular band of smaller radius.

The straightening and feeding portion of the machine 10 is generally supported on a base 20 which is formed of welded sheet steel as the major portion of the supporting structure to be described. The base 20 supports an electric motor 22 and an hydraulic pump 24 driven by the motor. This source of hydraulic power energizes the entire machine. The connecting hydraulic lines are not shown in the drawings or described as their nature is well known to those skilled in the art. A hydraulic flow control valve 28 is provided which may be manually adjusted to provide the desired full volume.

Similarly the electrical circuitry, which is housed in a control cabinet 26 supported on the base 20, is of the type generally associated with such machinery and the particular electrical inter-connections will not be described.

It is therefore seen to be an object of the present invention to provide a method of forming circular bands of sheet steel which will allow a complete closed band to be formed with no deviations from true circular form.

Another object is to provide machinery to economically practice such method.

A further object of the present invention is to provide a method of forming complete circular bands of sheet steel which comprises the steps of initially forming a partial circular band of a greater radius than the desired finished band from an elongated strip of stock, cutting oil the partial circular band from the remainder of the stock, and rerolling the band to diminish its radius and form a complete circle.

Another object of the present invention is to form a completely circular band through the method of initially pressing a strip of stock through a series of passive rolls in order to form a partial circular band having a greater diameter than that of the desired finished band, cutting off the partially formed band from the remainder of the strip of stock, and rerolling the partially formed band through powered rolls in such manner as to diminish the diameter and form a complete circular band.

Another object of the present invention is to provide apparatus in accordance with the above objects which includes means for correcting the tendency of the passive rolls for warping the material about an axis transverse to its length.

Another object of the present invention is to provide apparatus in accordance with the previous objects wherein the material is automatically handled between operations.

A further object is to provide apparatus in accordance wtih the previous object utilizing means for precisely measuring the length of strip which is fed through the passive rolls in order to form partial circular form which is then rerolled to form the final enclosed form.

Other objects, advantages and applications of the present invention will be made apparent by the following detailed description of a preferred embodiment of the invention. The description makes reference to the accompanying drawings in which:

FIGURE 1 is a perspective view of a machine embodying the present invention;

FIGURE 2 is a plan view of a portion of the machinery which initially rolls the band;

FIGURE 3 is a plan view of the machinery of FIG- URE 2 taken along lines 33 of that figure;

FIGURE 4 is a plan view of the machinery which re rolls the bend in such a manner as to complete it;

FIGURE 5 is an elevation view of the machinery of FIGURE 4; and

FIGURE 6 is a perspective view of a partially formed band.

An electric push button panel provides selective start and stop control over all of the elements of the machine as well as allowing start and stop control over an automatic routine whereby the operations which will be subsequently described are performed automatically in their proper sequence.

The strip 12 first enters the machine through a pair of locating rolls 34 which are supported on a sub-base 32. These rolls maintain the strip 12 in general vertical alignment for feeding through the machine. The strip 12 then passes between two horizontal guide blocks 36 which may be adjusted along a bar 38 extending transversely to the direction of feed of the strip 12 and having a T slot 40 in which the blocks 36 move.

The strip 12 then passes through a series of straightening rolls 42 which are disposed in a support member 44. These rolls act to remove any kinks from the strip. After passing through the roll housing 44 the strip 12 is again aligned in a horizontal plane by a pair of transversely adjustable guides 46 which are supported in a block as having a T slot 50 along which the guides 46 may be moved. The strip 12 next passes through a pair of longitudinally disposed retaining blocks 52. The blocks 52 are disposed parallel to one another and have recesses cut in their opposed surfaces. The edges of the strip 12 passes through these recesses so that the blocks 52 act to guide the strip over a portion of its length.

After passing through the guide blocks 52 the strip 12 passes between a pair of passive warping rollers 54 and 56 which have conjugate surfaces that are slightly lower at their center point than at their ends. That is, the lower roller 56 is concave while the upper roller 54 is convex. The spacing between the rollers may be adjusted by means of an adjustment nut 58 which moves the upper roller 54 in a vertical plane. These rollers therefore give the strip 12 a bowed cross-section with a low point at the center. This action corrects for the tendency for the subsequent rolls to how the strip with the high point at the center. It produces a completely rolled strip that is absolutely fiat in the transverse direction.

The strip next passes between a fixed lower roll 60 and two adjustable upper rolls 62. The rolls 62 are supported in a block 64. Spacing of this block 64 with relation to the rest of the machine may be adjusted by moving a wedge-shaped block 66 in a transverse direction through use of a hand wheel 68. The shaft of the wheel 63 is threaded and is attached to the block 66 by means of a connecting bar 72. Therefore, when the hand wheel 68 is rotated the shaft 70 moves transversely within its supporting block 74 and moves the wedge 66 which adjusts the block 64 in a direction perpendicular to the strip 12. The position of the roller 62 may be locked by means of a second hand wheel 76 which also threads on the shaft 70 and looks it against block 74.

The lower roll 60 extends into the space between the upper rolls 62 in such a manner as to bend the strip in a downward direction as it is forced between the rolls. By adjusting the exact height of the rolls 62 by means of the hand wheel 68 the exact diameter of the bend may be controlled.

The mechanism which forces the strip through the various rolls which have been indicated will now be described. Two hardened and ground shafts 86 are supported along opposite sides of the guide strips 52 at approximately the same height as the guides. The shafts 80 are fixedly supported above the sub base 32 by support members 82. Ball bushing guide members 84 surround each of the shafts and act to support a bridge member 86 between them. The bridge member 86 has a central aperture through which the guide bars 52 pass. On the top side of the bars it supports a hydraulic cylinder 88 which has shaft 90 journaled in a bushing 92. The shaft 99 has a flattened section 94 at its lower end which passes between the guide strips 52. The lower side of the bridge carries a block member 96. When the cylinder 98 is actuated so as to extend its rod 90 the strip 12 is captured between the lower end 94 of the rod 96 and the block 96. The entire bridge assembly 86 is then moved along the shafts 30 under the influence of a hydraulic cylinder 98 which has its rod 100 connected to the bridge member 86. The cylinder 93 is disposed in an aperture beneath the rolls 34- and 44 on the sub base 32. When the cylinder 98 extends its rod 160 the entire bridge assem bly moves toward the left as viewed in FIGURES 1, 2 and 3. The cylinder 88 has its rod extended at that time and it moves the strip 12 with it, passing the strip through various rolls.

At the left termination of the guides 52 another hydraulic cylinder 102 is disposed with its rod 104 in a vertical position. The cylinder 102 is supported above the guides 52 on a block 1136. When the rod of the cylinder 162 extends it captures the strip 12 against a lower bearing block 108.

The manner in which the initial roll is formed in the strip is therefore as follows. The bridge member 86 and its cylinder 88 are initially disposed in their far right position, that is, with the rod 160 of the cylinder 23 fully retracted. The control circuitry then directs a fluid flow to the cylinder 88 causing to extend its rod 90 so as to capture the strip 12 between the'rod section 94 and the block 96.

The cylinder 96 is then energized to cause its rod 1% to extend and to move the bridge toward the left, to the position shown in FIGURES 2 and 3. As this is done the strip 12 is drawn from its supply reel through the straightening rolls 42. The guides 34 and 36 act to maintain it in a proper disposition for entry into the straightening rolls. Its other end is passed through the warping rolls 54 and 56 and the bend rolls 6!} and 62. The end which has passed through the bending rolls 69 and 62 is bent in a downward, counter clockwise direction so as to partially surround the form which supports the roll 69.

The end of motion of the bridge 86 is signaled by a limit switch 112 which is tripped by an arm 114 extending from the bridge, the switch 112 acts through the control circuitry to halt the motion of the cylinder rod 196. Similarly, in the extreme right position the arm 114 actuates the limit switch 116. The distance between these limit switches is equal to the length of the strip which is passed through the rolls by one motion of the bridge 66.

When the bridge has reached its extreme left position the hydraulic cylinder 162 is energized and extends its rod to clamp the strip 12. The cylinder 88 is then de-energized and the cylinder 98 is energized so as to retract its rod and bring the bridge 86 back to its initial position. During this time the strip is maintained in position by the cylinder 102.

After the bridge 86 has moved a section of the strip through the rolls 6t and 62, that rolled section may be cut off from the main strip. This is done by a cutter 113 (FIGURE 3) which is carried in a support 114 which is hollowed for weight reduction and actuated by rod 116 of a hydraulic cylinder 118. The cylinder 118 acts in conjunction with a cylinder 120 in an hydraulic intensifier circuit such as is well known to those skilled in the hydraulic art to give a powerful stroke to the cutter 113. The cut-off of the strip 12 is at right angles to its length.

After the paritally formed band, indicated at 122, is cut off from the strip 12, it falls over the form 111] and is gravity fed into the chute 18. As its left most edge strikes the angle 124 of the chute it is pivoted about its lower point so that it rolls down the final section of the chute.

At the end of the chute it comes to rest'on a pair of bars 126 which are supported in parallel position across an opening 128 in the base 130 of the rerolling section 16 of the machine. As the partially formed band rests on the bars 126 it contacts a pair of rubber rollers 132 which may be revolved by an electric motor 134 through enclosed belt arrangement 136.

The rolls 132 cause the partially formed band to rotate in a clockwise direction as viewed from the left of the figures. The motor is so controlled that the rotation continues for 360 degrees. At some point in this rotation the edge of the partially performed band abuts against a stop block 138 which is pivotably supported on an arm 140 above the base 130. The stop prevents the band from rotating further and causes it to frictionally slide over the rolls 132. During this rotation a plate 142 which is also supported on the arm 140 prevents the band from falling to the left in the drawing. The band is supported on the right by a pusher plate 144.

The stop 138 acts to orient the band with respect to the machine. After the orientation has been accomplished the pusher block 144, which rides on two horizontal rods 146 that are supported in bushings 148, is moved to the left in the drawings under the influence of an hydraulic cylinder 150. The cylinder 150 is supported on a shelf 152 on the end of the base 130.

The pusher block 144 acts to move the band to the left in the drawings along the shafts 126. One end of the band thereby comes to rest between a power roller 154 and three passive rollers 156. The passive rollers are arranged about the powered roller so that a band rolled between them will assume their final proper diameter.

The three passive rollers may be moved between an operating position wherein they are disposed in close proximity to the power roller 154, and an open position wherein they are removed from the power roller 154 so that a band may be inserted or removed from between them, by a hydraulic cylinder 158. The two side pas sive rollers 156 may be independently adjusted as to their closed position by a hand wheel 160. The wheel operates through gearing (not shown) to move the two outside rollers independently of the center roller so as to vary the diameter band which will be formed between the rollers.

The roll 154 is powered by a motor 162 which acts through a right angle reducer drive 164. The output shaft 166 of the drive 164 is connected to the roller 154 through the circumference of the desired finished hand through a plurality of passive rolls adapted to form a circle of greater radius than said desired finished band; severing said rolled portion from said strip at a point which has been passed through said passive rolls; transferring said cut off large radius band to a plurality of powered rolls; and rerolling said large radius band so as to reduce its radius.

2. The method of forming complete circular bands of metal strip from length of strip stock which is longer than the circumference of the finished band, comprising: passing a predetermined length of strip stock equal to the circumference of the desired finished band through the aperture presented by a first pair of passive rollers at one side of the stock and a second passive roller on the other side of said stock so as to form a circle of greater radius than said desired finished band; severing said rolledportion from said strip at a point which has been passed through said rolls; and rerolling said large radius band so as to reduce its radius.

References Cited in the file of this patent UNITED STATES PATENTS 1,783,047 Marshall NOV. 25, 1930 1,791,257 Ziler Feb. 3, 1931 1,939,577 Sneed Dec. 12, 1933 1,973,436 Hjort Sept. 11, 1934 2,742,078 Williams Apr. 17, 1956

Images