Title: A device for releasinq and bendinq a substrate from a base plate

Technical Field

The present invention relates to a device for the preparation of a substrate adhered onto a surface of a plate, such as a shim adhered to a disc brake pad, where said preparation may comprise releasing and bending, and it may occur before an adhesion strength between the shim and the disc brake pad is subsequently tested using tensile testing.

Background Art

A disc brake pad comprises a steel plate where on the one side, a lining is facing the disc e.g. a rotating disc connected to the wheel, and on the other side often comprising a shim, i.e. a material for damping of noise during a brake application. Such shims are mostly glued onto the disc brake pad besides being riveted in order to adhere sufficiently to the disc brake pad. One of the quality tests of the disc brake pad is the testing of the strength of this glue connection. The glue connection is tested by conventional tensile testing. However, before being able to carry out this tensile testing of the glue connection, part of the shim is released from the disc brake pad to be able to grab around part of the shim in order to pull the shim off the disc brake pad.

The preparation of a shim before a tensile testing is at present carried out by hand by using hammer and chisel. First, the pad and the shim are fixed in a vice or like apparatus for fastening. The shim is then partly released by placing the chisel between the shim and the disc brake pad and then applying a force to one end of the chisel by swinging the hammer to hit that end of the chisel. When swinging the hammer, the chisel is given a certain force in order to wedge in under the shim and release it from the disc brake pad. The shim is to be released up to a predetermined straight line across the shim and then the released part of the shim is bent to an upright position being orthogonal to the plane of the disc brake pad.

In this upright position the shim is placed in equipment for tensile testing, and the released part of the shim is pulled upwards while holding down the rest of the shim. In this way, the adhesion between the shim and the disc brake pad is tested.

The chisel is held by hand, and when the chisel is wedged in under the shim, the aforementioned line is occasionally overstepped due to the fact that the blade of the chisel is not held parallel to the plane of the disc brake pad, or the cutting edge of the chisel is held at an angle to the aforementioned line. In this way the strength of the glue connection may to some extent be decreased before the actual tensile testing, leading to fluctuating strength results which are not representative for the actual strength of the glue connection.

Disclosure of Invention

An object of the present invention is at least partly to overcome the disadvantages of prior art and to provide a device for an improved preparation of a shim of a disc brake pad before being tested by the use of tensile testing.

The object of the present invention and other advantages appearing from the descrip- tion below are obtained by a device for preparation of a substrate such as a shim adhered onto a surface of a plate such as a disc brake pad, where said preparation occurs before an adhesion strength between the substrate and the plate is tested, said device comprises a fastening means for clamping the plate and part of the substrate during the preparation, and a releasing part having an edge for releasing the substrate from the plate, wherein the device further comprises a guide means for guiding the edge along the surface of the plate onto which the substrate has been adhered.

By providing a device of the present invention, an improved preparation of a substrate adhered onto a plate is obtained in that the releasing motion is controlled by the guide means so that the releasing of part of the substrate is performed sufficiently and in the same manner every time. Subsequently, the bending action is performed in the same way ensuring a sufficiently bending or at least the same bending every time a substrate is prepared by the device according to the present invention.

In another embodiment of the present invention, the guide means may guide the edge so that the edge is substantially orthogonal to a line defining a longitudinal extension of

the plate. Hereby it is obtained that the edge of the releasing part comes in parallel to the edge of the block of the fixing vice and ensures a proper bend.

Furthermore, the releasing part may be rotationally connected to the guide means ac- cording to the present invention.

Additionally, the releasing part according to the present invention may be rotationally connected to the guide means in at least two separated positions of the releasing part.

In yet another embodiment of the invention, the releasing part may be rotationally connected to the guide means by means of two sets of guide parts, wherein each set of guide parts may comprise a first guide part 8 rotationally connected to a second guide part 11 by means of a first axle 9, wherein the two sets of guide parts may be connected by means of the same first axle.

The device according to the invention may further comprise a torque arm for moving the releasing part.

Additionally, the torque arm may in another embodiment be pressed towards the first axle when the torque arm is moved for moving the releasing part.

Furthermore, the device may comprise a bending means for bending a partly released substrate to an upright position according to the present invention.

In one embodiment, the bending means may comprise a bending arm being fixedly connected to the releasing part and rotationally connected to the guide means; so when moving the bending arm, the releasing part is pressing towards the substrate from underneath the substrate.

In another embodiment, the device may further comprise a ground plate onto which the plate is placed, and onto which ground plate the guide means and the torque arm are rotationally connected by means of a second axle.

Advantageously, the device may in another embodiment further comprise a slide onto which the plate is positioned, and wherein the slide is movable in a transitional direction of a longitudinal extension of the ground plate.

Finally, the guide means may in another embodiment be movable for an adjustment in the longitudinal direction of the ground plate.

Brief Description of the Drawinq(s)

The invention is explained in detail below with reference to the drawing(s), in which

Fig. 1 shows one embodiment of the device of the present invention where a substrate has been released from a plate and bent to an upright position,

Fig. 2 shows a section of the device in Fig. 1 in a first position where the plate with an unreleased substrate has been clamped ready for the preparation,

Fig. 3 shows a section of the device in Fig. 1 in a second position where the substrate has been partly released from the plate,

Fig. 4 shows a section of the device in Fig. 1 in a third position in which position the substrate has been bent to an upright position,

Fig. 5 shows a section of the device in Fig. 1 in a fourth position in which position the preparation of the substrate has ended,

Fig. 6 shows a front view of the fastening means of the device.

Detailed description of the preferred embodiments

In Fig. 1, a device 1 according to an embodiment of the present invention is shown having a plate, such as a disc brake pad, positioned after a preparation in which preparation the substrate, such as a shim, has been partly released and subsequently bent to an upright position. In Fig. 2, the disc brake pad 2 having a shim 3 glued onto its one surface is shown in its fastened position. The shim and the disc brake pad are fastened to a ground plate 13 of the device by means of a fastening means 4 as shown in Fig. 6. In the first position, the shim is still glued or in another way adhered onto the disc brake pad. In this un-released position of the shim, the shim may either be completely or par-

tially adhered onto the disc brake pad. The device has a wedge part 5 having an edge 6 being out of contact with the shim 3. One end of the wedge part 5 is fixedly connected along a first end part of a bending arm 7. The wedge part 5 is further rotationally connected to a first guide part 8. The bending arm 7 is at its first end part rotationally connected to another first guide part 8. The two first guide parts 8 are in this embodiment shown as two separate parts, however the first guide parts 8 may in another embodiment be comprised in one first guide part 8 having a fork-like shape for connection to the bending arm 7 and the wedge part 5.

The first guide parts 8 are also rotationally connected to a first axle 9, around which first axle, a ball bearing 10 is fixedly connected so that the first axle 9 penetrates the centre of the ball bearing 10. The first axle 9 is further rotationally connected to a second guide part 11. In this embodiment, the first axle 9 is rotationally connected to a first end part of two second guide parts 11. In another embodiment of the present invention, the two second guide parts 11 are made in one part having a fork-like shape for connection to the first axle 9 in two separated positions of the first axle 9.

The two second guide parts 11 are each rotationally connected at their second end part to a second axle 12. The second axle 12 further penetrates a protrusion 14 of the ground plate 13 and one end part of a torque arm 15. The torque arm 15 abuts against the outside of the bail bearing 10 so that when the torque arm 15 is pressed down towards the ground plate 13 of the device 1 , the torque arm 15 rolls in relation to the first axle 9 transmitting almost all the pressing force applied from the torque arm 15 via the ball bearing 10 to the first axle 9. The first axle 9 is then pressed down towards the ground plate 13, and the first end part of each second guide part 11 is pressed down and the edge 6 of the wedge part 5 is then pressed towards the shim 3 and disc brake pad 2. In this way by pulling down the torque arm 15, the shim 3 is released from the disc brake pad 2 in that the edge 6 is wedged in under the shim 3 for releasing the shim 3. In Figs. 3, 4 and 5, the shim 3 is shown in a partly released position.

In the Figs, the edge 6 is shown as guided by a guide means comprising the two first guide parts 8, the second guide parts 11 , the first axle 9 and the second axle 12. The guide means guides the releasing edge so that the releasing edge 6 during this guiding is orthogonal to a line defining a longitudinal extension of the disc brake pad, whereby the releasing edge is parallel to an edge 23 of the fastening means facing the part of the shim to be released.

When a sufficient part of the shim 3 has been released from the disc brake pad 2, the edge 6 of the wedge part 5 has reached a certain predefined line and the wedging stops. Subsequently, the bending arm 7 is pulled down towards the ground plate 13 in order to bend the shim 3, as shown in Fig. 4. In this way, the wedge part 5 is rotated around the edge 5 by the pulling in the second end of the bending arm 7. When the bending arm 7 has been pulled sufficiently down towards the ground plate, the shim 3 is bent to an upright position as shown in Figs. 4 and 5. In the upright position of the shim 3, the shim 3 has been bent 90°-95°. In case the shim 3 is bent less than 90°, the later tensile testing of the shim is influenced in the way that some of the force used in the initial part of the tensile testing is used for bending the shim up to the 90°. Additionally, most shims are partly made from a metal such as steel which when bent has a tendency to swing back resulting in a smaller angle than the bending angle. Thus, it is important that the shim has been bent 90° or slightly more.

The device 1 of the present invention may be used for a variety of types and sizes of disc brake pads 2 having a shim 3 adhered onto one of its surfaces 16. The disc brake pad 2 is in this embodiment placed on a slide 17 being movable in a transverse direction in relation to the longitudinal extension of the ground plate 13. The slide 17 may in this way be adjusted in the transverse direction in order to fit a large variety of disc brake pads 2 in relation to the width of the disc brake pads. Furthermore, the device 1 is adjustable in order to fit different lengths of the disc brake pad 2. An adjustment of the device 1 in the longitudinal direction may be performed by moving that part of the device 1 comprising the wedge part 5, such as the protrusion part connected to the guide means and the torque arm. In another embodiment the slide 17 may further be movable in the longitudinal direction of the extension of the ground plate 13 in order to be able to adjust the device to prepare different lengths of disc brake pads.

An adjustment of the device 1 to fit and prepare different lengths and widths of the disc brake pads 2 may be performed either in steps or ungraduated. The ground plate 13 may be equipped with a ruler, a scale or the like indication for an indication of the position of the slide for fitting a specific size of the disc brake pad 2. Additionally, the fastening means 4 is adjustable in the same way in order to fasten the disc brake pad 2 in the right position depending on the length of the disc brake pad 2. The foundation of the fastening means 4 or the ground plate 13 of the device 1 may in the aforementioned way be equipped with a ruler, a scale or the like for a quicker adjustment of the

device 1 in preparation of a disc brake pad 2 having a different size than the latter disc brake pad 2 having been prepared before a tensile testing.

In Fig. 6, the fastening means 4 for clamping of the disc brake pad is partly shown. The fastening means comprises an adjustable clamping arm 18 and is at its one end rota- tionally connected to a block 19 for contacting and clamping the shim 3. The block has an edge 23 facing that part of the shim which is to be released. The shim 3 may be riveted besides being glued to a surface of the disc brake pad as shown in Fig. 1. These rivets 20 may in some cases protrude from the surface of the shim 3 opposite the disc brake pad 2, and therefore the block 19 for clamping of the disc brake pad 2 has a recess for receiving the rivets 20 protruding the surface of the shim 3. Additionally, the edge of block 19 facing the shim 3 during clamping of the disc brake pad has a rounding radius in the range of 0.1 -4.0mm (RO.1mm - R4.0mm). This rounding radius corresponds to the rounding radius of the bend of the shim after part of the shim has been bent to an upright position.

Furthermore, the surface of the block 19 facing the upright part 21 of the shim 3 is preferably inclined inwardly by an angle up to 10°, more preferably by an angle up to 5°. First in the preparation of the shim, the wedge part 5 wedges in under part of the shim, and the bending arm 7 is then pulled towards the ground plate so that the surface of the wedge part facing the shim is pressed up against the aforementioned inclined surface of the block 18. In this way, the shim is bent a little more than 90° due to the fact that the surface of the block is inclined inwardly. This complies with the fact that since the shim comprises a metal plate, the shim has a tendency to swing backwards again after being bent more than 90° resulting in a smaller angle.

As can be seen in Fig. 6, the fastening means clamps the disc brake pad and only part of the shim since the other part of the shim must be available for wedging of the edge of the wedge part in the preparation of the shim before the tensile testing. The surface of the disc brake pad onto which the shim adheres may have some recesses (not shown). When clamping part of the shim, the edge of the block 19 facing the shim must be free of these recesses so that the block abuts against that part of the surface of the disc brake pad without the recesses.

The wording "disc brake pad" in this context may also be a brake pad, a disc brake pad or any kind of pad assembly for providing a braking action when pressed towards a

moving element. The device according to the present invention is here shown to partly release a shim from a disc brake pad for an illustrative purpose, only, and the present invention is not limited to such preparation. The device of the present invention may also be used to release other kinds of substrate adhered to another substrate, such as a plate, before the adhesive connection between the two substrates is tested in some kind of bonding testing such as tensile testing. The device may furthermore be used to bend the substrate to an upright position before the subsequent testing of the adhesive bonding.

According to an embodiment of the present invention, the releasing part 5 is formed having a wedge shape. In another embodiment, the releasing part may be in form of a blade having a cutting edge 6. The cutting edge 6 may be serrated or in the form of a straight line. The edge of the releasing part has in one embodiment of the present invention a width equal or larger than a radial width of the disc brake pad.