KR0170814B1 - Method and apparatus for producing brake shoe - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a brake shoe for a drum brake assembly, and to a manufacturing apparatus suitable for the method, wherein the friction lining is laminated with an adhesive material on the shrim, the laminate is pressed, and the electrode A circular arc with two ends facing the friction lining is made by energizing the brake shoe body so that the brake shoe body is heated evenly while the brake shoe body is energized through a pair of electrodes pressed against both ends of the brake shoe. And a metal brake shoe body consisting of a curved rim and a parallel flange projecting radially inward from the edge end of the rim.

Description

Brake shoe manufacturing method and apparatus for manufacturing same

1 is a plan view showing one embodiment of a brake shoe body used in the method of the present invention.

FIG. 2 is a side view of the brake shoe main body of FIG. 1 seen from the direction of arrow X. FIG.

3 is a partially enlarged side view of the brake shoe main body of FIG. 1 seen in the direction of an arrow Y. FIG.

4 is a plan view of a laminate-composite used in the method of one embodiment of the present invention.

FIG. 5 is a side view of the laminate in FIG. 4 as seen in the direction of arrow X. FIG.

6 is a perspective view of the laminate of FIG.

7 is a side view of the brake shoe body used in the method of one embodiment of the present invention.

8 is a plan view of the apparatus of one embodiment of the present invention.

9 is a partial cross-sectional view of the apparatus of FIG.

FIG. 10 is another partial cross-sectional view of the FIG. 8 device.

11 is a partial side view of the FIG. 8 device.

12 is a bottom view of the device of FIG. 10 as viewed from the direction of arrow A. FIG.

* Explanation of symbols for main parts of the drawings

1: brake shoe body 11: shrim

12 flange 13 cross section

2: adhesive 3: friction lining

4: fixing means 411: support member

5: energization means 51: electrode for direct energization

52: pressure clamp 6: press means

61 pressure band 7: support means

The present invention relates to a method for manufacturing brake shoes for a drum brake assembly and a manufacturing apparatus suitable for the method.

In the prior art, a method for producing a brake shoe for a drum brake assembly by attaching friction linings to a brake shoe body with a thermosetting adhesive is applied to the brake shoe body and the friction lining, respectively, and after drying, the brake shoe The main body and the friction lining are compressed together with a pressure jig, and the brake shoe main body and the friction lining are treated by hot air heating in a heating furnace.

The treatment of thermosetting adhesives by the hot air heating method is difficult due to its low thermal conductivity and that other parts, including crimp clamps, rolling mechanisms and furnace walls, are also heated to prevent efficient and partial heating of the coated parts. Involve the problem.

As a means of solving this problem and enabling the downsizing and rapid heat treatment of the equipment, Japanese Patent Laid-Open No. 61-153026 proposes a high frequency induction heating method. This method enables fast heat treatment, but has a problem of low thermal efficiency because it is an indirect heating method by eddy current. Another problem is that the shape and facilities of the coil are complicated to uniformly heat the brake shoe body having a complicated shape.

One method is disclosed in Japanese Patent Laid-Open No. 7-179824 as a method of bonding a brake shoe body and a friction lining at a low cost using a small and simple device. A metal brake shoe body including a friction lining and a shoe rim is provided. The heat of the brake shoe body generates heat of Joule by energizing the brake shoe body through two electrodes pressed at both ends of the shoe rim when heated and compressed with the adhesive placed between them for adhesion. . A problem in the method of causing the brake shoe body to generate heat by direct energization is a high heat generation near the contact point where contact between the two electrodes and the brake shoe body is insufficient, thereby preventing uniform heating due to contact resistance. Conversely, even if the contact resistance is reduced as low as possible, the heating may not be uniform depending on the structure of the device for supporting the heat conduction or the brake shoe body with the electrodes.

The object of the present invention is to bond the friction lining to the brake shoe body with the shrim by heating and compressing the adhesive between the friction inning and the shrim, so that it can be made in a short time with high thermal efficiency and the uniform heating can be easily performed. To provide a way to make it work. Another object of this invention is to provide a manufacturing apparatus suitable for the method.

As a result of the research to solve the problem, the inventors made the metal brake shoe main body to generate heat by direct energization through the electrodes pressed at both ends, and the contact point was properly controlled through the pressure at which the electrode was pressed to the main body. It has been found that the brake shoe body can be heated evenly by adjusting the contact resistance of. Furthermore, the inventors further found that the thermal tool passing through the contact surface and the temperature difference between the parts near the contact surface are fixed by fixing the brake shoe body by means of a fixing device made of insulating material either electrically or in temperature during the compression and compression process. It has been found that this can be reduced by reducing the contact area of the brake shoe body with as little as possible. Based on this finding, this invention was completed.

In other words, the invention is a frictional lining that is metal and is substantially arcuately curved, a substantially arcuately curved shoe rim with two substantially opposite ends, and radially inwardly from both edges of the shrim. Consisting of a pair of parallel flanges extending outwardly, which are arranged to place the brake shoe body at both ends of the arc with end surfaces comprising separate planes facing each other. Contacting the flange contacting the folded shrim in two radially inward directions at each of the two ends, the method comprising: applying at least one friction lining to the radial outer circumferential surface of the shrim with an adhesive interposed to form a locus laminating, a pair of electrodes at both ends of the brake shoe body such that the electrodes contact at least two planes of two cross sections of the brake shoe body. In order to press the poles and to ensure that all parts of the brake shoe body generate uniform heat, the worms are squeezed and the electrodes are squeezed at both ends of the brake shoe body and the pressure is adjusted and the brake shoe body is energized. Provided is a method for removing a brake shoe for a drum brake that adheres a friction lining to a brake shoe body which is electrically charged.

The present invention also provides a suitable apparatus for implementing the above method.

That is, the apparatus of this invention is a device which manufactures the brake shoe for drum brakes by apply | coating at least 1 friction lining to the brake shoe main body with the adhesive agent interposed, and heating and crimping | compressing the red body, This brake shoe main body Is made of metal and bent substantially arc-shaped,

A substantially arc-shaped bent seam having two substantially opposite ends, and

Consisting of a pair of parallel pulleys projecting radially inwardly from both edges of the shrim, the shrim having, at each of its ends, both cross sections including respective planes facing each other at both ends of an arc; Fold radially inwards with the flange contacting the shrim to provide a brake male body, the friction lining is applied to the radial outer surface of the shrim and the adhesive interposed between them to form a locus; Is for supporting the chuck body horizontally with the outer side of any of the flanges facing downwards, the flange of which is made of steel, thermally sprayed ceramic, and facing down at the plural pats of the antler. A plurality of erected support members each having an outer surface and a respective upper surface in contact with the outer surface of the friction lining supporting means consisting of blocks; For holding the supported locust in place, it is made of steel and has a ceramic flame-coated plurality of locking members and a plurality of locking members at radial portions of the brake shoe body, respectively, in the radial direction of the flange. Locking means consisting of members boiling out radially from the inside of the arc of the brake shoe body to contact the inner edge and releasing the locking member from the edge of the flange to disengage the locking; And a pair of energizing electrodes, a pressing device, and a power supply means to which the electrodes are connected, wherein the electrodes can contact a plane of the cross section of the brake shoe body, and the pressing tools of the electrode The electrode from the end face of the brake shoe body in order to approach the plane in contact with the plane of the cross section of the brake shoe body of the fixed locust, and to press and release the contact of the electrode against the plane of the cross section of the brake shoe body under adjustable pressure. The power supply means for electrically energizing the brake shoe body to generate heat while the electrode is pressed against the plane of the cross section of the brake shoe body; And pressing means located radially outwardly of the brake shoe body of the fixed worm body and pressing the friction lining of the worm body against the radially outer surface of the shoe rim.

The brake shoe body used in this invention is part of the drum brake assembly and has a substantially arcuate form extending in a substantially near circle shape.

1 is a plan view of a brake shoe body used in the implementation of this invention.

FIG. 2 is a side view of the brake shoe main body of FIG. 1 seen from the direction of arrow X. FIG. The brake shoe body 1 is substantially curved in the form of an arc and has a pair of parallel flanges protruding radially inwardly on both sides of the shrim 11 with both ends in an opposing position, 12). At each end of both ends the shrim 11 is folded in two radially inwards to contact the flange 12. FIG. 3 is a partial band side view of the brake shoe main body 1 of FIG. 1 viewed in the direction of arrow Y, and is a cross section in which the folded shoe rim 11 forms an M shape together with the flange 12. The brake shoe body 1 therefore has two cross sections 13 with respective planes 14 facing each other.

The brake shoe produced by the method of the invention in a drum brake assembly is secured in the drum by its ends 13 being fitted at both openings of the tubular sleeve. The tubular sleeve includes an actuating mechanism capable of expansion and contraction, which actuates an end face 13 of the brake shoe body 1 to cause the brake shoe to expand and contract radially in response to the expansion and contraction of the actuation mechanism. Has grooves at both ends. The dean of the operating mechanism causes the friction lining to contact the inner surface of the drum to extend the brake shoe and activate the drum brake, and the hydrangea of the operating mechanism to disengage the extension of the brake shoe and to bring the brake into operation. The friction lining that was in contact with the drum's inner surface is retracted. The brake shoe body is therefore preferably made of a metal, such as mild steel, with high rigidity and sufficient elasticity.

In the method according to this invention, at least one friction lining is first radially deposited on the outer surface of the shoe rim of the brake shoe body with an adhesive material therebetween in order to obtain a red worm. FIG. 4 is a plan view of the red larva of the present invention, FIG. 5 is a side view of the red larva of FIG. 4 seen from the X direction, and FIG. 6 is a perspective view of the red larva of FIG. Although the red worm body of the present invention is composed of a brake shoe body 1 and two friction linings in which a thin film is radially covered on the outer surface of the shoe rim 11 of the brake shoe body 1 with an adhesive 2 between the friction linings ( The number and shape of 3) may be modified by such things as the conditions or appliances that will be required for the next heating and pressing process. When the side edges of the shrim 11 are rounded, it is preferable to cover the thin film only partially without enclosing the friction lining 3 as shown in FIG.

Friction linings provide a friction surface to the brake shoe and are made of non-conductive nonmetallic material. Friction linings, for example, are made by mixing short fibers of asbestos, glass or plastic with adhesives such as thermosets, heating them and pressing them into a mixture in a bent plate that radially fits on the outer surface of the shrim.

In general, lamination is applied radially on the outer surface of the brake shoe body and the inner surface of the frictional lining of the brake shoe, and the adhesive is dried with hot air, and then the frictional lining on the shoerim is applied to the adhesive layer applied therebetween. Appropriate. Examples of suitable adhesives are thermosetting resins such as phenolic resins and epoxy resins that are highly resistant to impact, refraction and peeling.

When carrying out the method of the invention it is preferred to use a plurality of fixing members made of steel and coated with ceramic to hold the red worm in place. In one embodiment of this method, the locust is fixed by squeezing a plurality of holding members of a plurality of portions of the radially inner edge of the flange. Fixing a plurality of holding members by contacting a plurality of holding members at edges of the flange tends to contact a contact surface between the holding member and the brake shoe body, thereby effectively preventing the temperature unevenness of the brake shoe body due to thermal conduction to the holding member. The holding member made of steel is strong enough to withstand the pressure applied to the red worm when pressed, and the insulating and heat resistant ceramic coating prevents the holding member from being filled or heat-conducted.

A pair of electrodes for electric charging is pressed on both ends of the brake shoe body in order to minimize contact of the electrodes to both fixed cross-sectional surfaces of the brake shoe body of the fixed red body. The brake shoe body is then charged directly to generate heat while the locust is squeezed. The electrodes can be pressed against the ends of the brake shoe body so that the electrodes only adhere to the planes of both cross sections of the brake shoe body. The thermosetting adhesive is treated with the heat generated by energization and the friction lining is strongly adhered to the shrim.

If an electric current passes through the brake shoe main body in a state where the electrode is insufficient in contact with the plane of the cross section of the brake shoe main body, the end of the brake shoe main body surrounded by the dashed-dotted line A of FIG. 4 generates high heat, thereby providing uniform heating. Could not be performed. If the contact area is too large, overheating due to contact resistance is reduced, but the temperature of the part A will be lowered by the heat conduction to the electrode, and uniform heating cannot be achieved.

If the brake shoe body is not heated evenly, the friction lining cannot be evenly bonded. The brake shoe body is generally coated with a variety of paints such as corrosion-proof primers. Another problem that can occur in overheated areas is the deterioration and discoloration of the paint, which worsens the quality of the brake shoe product.

According to this invention, the pressure at which the electrode is pressed against the brake shoe body is controlled to regulate the contact between the electrode and the plane of the end surface of the brake shoe body, thereby enabling uniform heating.

Since the brake shoe main body used in the present invention has a substantially arc-shaped path that is close to a circle, the brake shoe main body has a large electric resistance due to a long electric circuit between both end surfaces of the arc shape through which current passes. It is also useful in that it generates heat easily. Moreover, the folded cross section of the brake shoe body facilitates the formation of a plane used for uniform contact with the electrode.

The red worm is squeezed while the brake shoe body generates heat by direct energization.

The current passing through the brake shoe body may vary depending on the type of adhesive and the material of the brake shoe body, and generally 2 to 20 V and 800 to 1,500 for the entire brake shoe body to be uniformly heated between 220 ° C and 280 ° C. A current of A is preferred. The pressure applied to the antagonist is generally 7 kg / cm 2 or more, and 7 to 20 kg / cm 2 is preferable.

For example, when a current of 3 V / 1000 A passes through the brake shoe body and the locust is pressed at a pressure of 10 kg / cm 2, the thermosetting adhesive is treated for 2 to 5 minutes with the heat generated by the brake shoe body and exhibits sufficient adhesion. Although pressure and heat may stop at the same time, it is desirable to continue pressing until one to two minutes after the end of heating to smooth out the curing distortion of the adhesive.

In the heating and pressing process, the radial outer surface of the non-friction lining can be applied with the same thermal conductive coating as the friction lining to prevent the temperature increase of the brake shoe body in this part.

Made of ceramic or iron and made of ceramic, at least in part, on the exposed part of the adhesive layer and flange when contacting the friction lining with one or both sides of the flange of the locust to prevent slippage of the friction lining during heating and pressing Electrically or thermally insulated, thermally resistant caps, such as a stopper, can be applied. In such a case, it is desirable to apply a large number of small plugs to each receding portion in order to minimize the total contact area and to minimize the temperature difference of the brake shoe body due to the contact, rather than to completely plug along the flange of the laminated part. Do.

In the method according to the invention, only the brake shoe body is heated by the heat of Joule generated by direct energization and the brake shoe body is uniformly heated by adjusting the pressure at which the electrodes for charging are pressed onto the brake shoe body. High thermal efficiency In addition, since the contact area between the brake shoe body and the fixing member is small and the fixing members are coated with ceramic having excellent heat insulating properties, a uniform temperature of the brake shoe body can be maintained during the heating and pressing process. Therefore, according to the method of the present invention, the friction lining on the brake shoe body can be carried out efficiently, uniformly and quickly. In addition, the method of the present invention is excellent in execution efficiency because the crimped state can be easily made and kept stable.

8, 9, 10, 11 and 12 show various forms of one embodiment according to the invention suitable for this invention.

8 is a plan view of the device of one embodiment according to the present invention, in which a locking means 4 comprising a plurality of fastening members 411 used as ceramics, and an energization comprising a direct current transfer electrode 51 are shown. Means 5 and two pressing means 6. FIG. 9 is a partial cross-sectional view illustrating the fixing means 4 of the apparatus shown in FIG. 8 and the supporting means for leveling the locust, and the supporting means and the fixing means 4 present in different cross-sections for convenience of explanation. Are displayed together. 10 is a partial cross-sectional view illustrating the energization means 5.

The fastening means 4 comprise a central block 42 which is moved up and down by the air cylinder 43, the central part 42 having a larger diameter lower shell 421, a smaller one. It has a fixed cylindrical shell structure including an upper shell 423 of diameter and a taper shell 422 connecting the upper shell 423 and the lower shell 421. A plurality of pins 41 inserted into the cylinder 43 around the center portion 42 are arranged radially, each pin 41 constitutes one end and the fixing member 411 in contact with the structure of the center portion 42 To have one end. The plurality of fixing members 411 come into contact with the flange edges of the brake shoe body to fix the red worm in place. Radial to the room indicated by the sliding in the cylinder 43 as the diameter of the structure causing the fixing member 411 to contact or fall off the edge of the flange by moving the center portion 42 up and down. The pin 41 moves.

In this embodiment the support means consists of a plurality of supporting blocks 7 of fixed structure, which are made of steel and are arranged along a substantially arc of the locus. Each support 7 is coated with at least the upper surface 71 of a thermally sprayed ceramic and the locust supports the friction lining 3, the exposed surface 2 of the adhesive layer and the partial surface in contact with the upper surface 71. One flange and further contacting the bottom surface of the locust is maintained horizontally by the support member. The support 7 in contact with a plurality of portions of the bottom surface of the locust also prevents the upper surface 71 from slipping or scratching in the width direction during the heating and pressing process for the friction lining adhesive treatment. That is, the support 7 also serves as the plug mentioned above.

As shown in FIG. 9, the apparatus of the present invention includes an upper stopper for reliably preventing slippage of the friction lining or scratching in the width direction. FIG. 11 is a partial side view of the top plug 9 and FIG. 12 is a bottom view of the top plug 9 of FIG. 11 as seen from the arrow A direction. The top closure 9 is made of steel and at least the bottom surface 911 comprises a plurality of stopper blocks 91 which are thermally sprayed with ceramic, on which the friction lining 3 and the antagonist are placed horizontally. The flanges on the top surface will partially touch. The upper stopper 9 is moved up and down by the air cylinder 92. When the upper stopper 9 is lowered, the bottom surface 911 of the stopper 91 comes into contact with a plurality of parts of the worm to hold the friction lining in place, and the contact is made by the upper stopper 9 being It is released by moving up. In FIG. 12, the red worm that comes into contact with the stopper 91 is shown by a dashed-dotted line.

The electricity supply means is connected to and attached to the lower end of the electrode 51 to the power supply means. At its upper end, one side of each electrode faces the cross section of the brake shoe body and the other opposite sides of the electrode are between the electrodes 51 and the pressing jig 52. It is fixed to two plate clamps 52 which are arranged parallel to each other and extends toward the radially outer side of the stack together with two heat insulating plates 56 respectively placed on each other. The two press clamps 52 are connected by springs 54 loosely plugged into two cavities made at opposite positions. When the brake shoe main body 1 is not energized, the contact between the end of the electrode 51 and the end surface 14 of the brake shoe main body 1 is released by the force of the spring. When the pressing clamp 52 is pressed radially outwardly from the spring 54 by a pair of air cylinders 53 at a pressure perpendicular to the surface of the plate, the two support portions 55 serve as support points. The electrodes 51 are in contact with the end surface 14 of the brake shoe body 1, respectively. In this embodiment, the crimping tool of the device of the invention comprises a crimp clamp 52, a heat insulation plate 56, a spring 54 and an air cylinder 53 and a support 55. The contact between the electrodes 51 and the plane 141 of the cross section 14 of the brake shoe body 1 can be adjusted by adjusting the pressure applied by the air cylinder 53.

Each pressing means 6 comprises a pressure band 61 and a pressure band 61 made of a spring material and having a curved portion for forming a surface corresponding to the radially outer surface of the friction lining 3 of the worm body. The holder 62 for holding, the pressure band fitted to the holder 62 to apply pressure, contact the friction lining 3 from the radial outside of the brake shoe body and push the pressure band 61 there from to release the pressure. A pair of hydraulic cylinders 63 for loading, and a pair for supplementing the pressure applied at both ends of the friction lining 3, has a hydraulic cylinder 64. The brake shoe body 1 is directly charged by the energizing means 5 to generate heat when the locust is pressurized by the compression means 6 so that the brake shoe body 1 and the friction lining 3 It is strongly attached by the adhesive agent 2.

The radially outer side of the locust is provided with a tool 8 for contacting the thermally conductive contact member 81 which is about the same as the thermal conductivity of the friction lining to the radially outer surface portion of the shrim without friction lining. The tool 8 comprises an air cylinder 82 which brings the contact member 81 and the contact surface of the contact member into contact with the radially outer surface of the shrim and drop to release the contact. During the heating and pressing process, the contact member 81 maintains contact with the exposed portion of the radial outer surface of the shrim to prevent the temperature of this portion from rising above the temperature of the other accumulated portions.

Claims (3)

A substantially arc-shaped bent rim having a metal and substantially arcuate shape and having two substantially opposing ends, and a pair of parallel flanges extending radially inward from both edges of the shrim; flange, which is folded in two radially inward directions at each of its ends to place the brake shoe body at both ends of the arc having both end surfaces including separate planes facing each other. The brake shoe body in contact with the flange in contact with the shrim is a method of adhering a friction lining, the method comprising applying at least one friction lining to the radial outer circumferential surface of the shrim with an adhesive sandwiched therebetween to form an impeller. laminating, so that the electrodes contact at least the two planes of the two cross sections of the brake shoe body. Pressing a pair of electrodes on both ends of the brake and in order for all parts of the brake shoe body to generate uniform heat, the worms are squeezed and the electrodes are pressed on both ends of the brake shoe body and the pressure is adjusted. And a brake shoe for drum brakes, wherein the brake shoe body is electrically charged. 2. The method of claim 1, wherein a plurality of fastening members made of steel and thermally sprayed with ceramic are formed by laminating a friction lining with an adhesive material sandwiched therebetween on a radial outer surface of the shrim to form a locust. Locking the locust by contacting a plurality of portions of a basal inner edge, pressing the electrode against two flat faces of both end faces of the brake shoe body, and squeezing the locust And electrically charging the brake shoe body to heat, by regulating the pressure that is pressed against the two planes of both end surfaces of the brake shoe body so that all parts of the brake shoe body heat up uniformly. A device for manufacturing a brake shoe for a drum brake by applying at least one friction lining to a brake shoe body with an adhesive sandwiched therebetween and heating and compressing the load body, the brake shoe body being made of metal and substantially It consists of an arcuate bent, substantially arcuate curved rim having two ends, and a pair of parallel flanges projecting radially inwardly from both edges of the rim, Radially folding in two radially with a flange in contact with the shrim to provide a brake shoe body having both cross-sections having respective cross-sections facing each other at both ends of the arc at each end, forming the friction lining antagonist To the radial outer surface of the shrim and the adhesive placed between them for This device is intended to support the chuck body horizontally with the outer side of any of the flanges facing downwards, which is made of steel, thermally sprayed into the ceramic membrane, and below the plural parts of the enemy body. Supporting means, consisting of a plurality of supporting blocks of erect form, each having an upper surface which is in contact with the outer surface of the facing flange and the outer surface of the friction lining; For holding the supported locust in place, a plurality of locking members made of steel and flame-coated ceramic and a plurality of portions of the brake shoe body, each of which is radially oriented on the flanges. Locking means consisting of members boiling out radially from the inside of the arc of the brake shoe body to contact the inner edge and releasing the locking member from the edge of the flange to disengage the locking; And a pair of energizing electrodes, a pressing device, and a power supply means to which the electrodes are connected, wherein the electrodes can contact a plane of the cross section of the brake shoe body, and the pressing tools of the electrode The electrode from the end face of the brake shoe body to approach the plane in contact with the plane of the cross section of the brake shoe body of the fixed locust, and to press and release the contact of the electrode against the plane of the egg surface of the brake shoe body under adjustable pressure. The power supply means for electrically energizing the brake shoe body to generate heat while the electrode is pressed against the plane of the cross section of the brake shoe body; And pressing means located radially outwardly of the brake shoe body of the fixed worm body and pressing the friction lining of the worm body against the radially outer surface of the shoe rim. Manufacturing equipment.