JPH0571564A - Grinding of drum brake shoe lining - Google Patents

Abstract

PURPOSE:To provide a method for grinding a drum brake shoe lining which can improve workability and the yield of products. CONSTITUTION:A shoe assembly body 22 which is constituted by attaching a lining 21 on a shoe 20 is assembled on a jig 24, and the lining 21 is ground by a grinder 11 by revolving the shoe assembly body 22, together with the jig 24, and the outside diameter dimension of the lining 21 is adjusted to a prescribed dimension. A sensor 25 for detecting the surface position of the lining 21 of the shoe assembly body 22 installed on the jig 24 is installed, and grinding is carried out, detecting the position of the outer surface of the lining 21 by the sensor 25, and the position information of the lining 21 which is supplied from the sensor 25 is compared with a standard position which is previously set, and the position of the outer surface of the lining 21 is set within a standard range.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for lining a drum brake shoe.

[0002]

2. Description of the Related Art A drum brake shoe used in a drum brake device has a shoe assembly in which a lining is heated and pressed to adhere to an arc-shaped shoe outer surface, and the outer surface of the lining has the same diameter as the inner surface of the drum of the drum brake device. It is ground so that it is adjusted to obtain a predetermined braking force. Conventionally, when polishing the lining of the shoe assembly, the shoe assembly was assembled to a predetermined jig, rotated together with the jig, and polished by a rotating grindstone to adjust the outer diameter to a predetermined value. The polishing apparatus has a table that can be moved and adjusted in the X, Y, and Z directions with respect to the rotating grindstone, the jig is mounted on the table, and the shoe assembly fixed by this jig is The position of the table is set so as to have a predetermined position and a predetermined cut position with respect to the rotary grindstone, whereby the cut amount of the lining is made constant and the outer diameter dimension of the lining is made constant.

[0003]

Since the lining is made of a resin material mixed with a friction material such as metal fibers, the lining is relatively soft and the rotary grindstone is relatively less worn. However, during polishing of the shoe assembly in a large amount, the rotary grindstone still wears, which causes a problem that the outer diameter of the lining changes. Conventionally, the outer diameter of the shoe assembly is inspected by polishing a predetermined number of the shoe assembly and then performing a sampling inspection for each predetermined lot to confirm the outer diameter of the lining with a dial gauge or the like. However, even if the sampling inspection is performed, it is troublesome, but once a defective product is generated, the shoe assembly of the entire lot to which the defective product belongs may be a defective product, resulting in poor workability and yield.

Therefore, the present invention has been made to solve the above problems, and an object of the present invention is to provide a lining polishing method for a drum brake shoe which can improve workability and product yield. It is in.

[0005]

The present invention has the following constitution in order to achieve the above object. That is, a shoe assembly having a lining adhered to a shoe is assembled to a jig, and the shoe assembly is rotated together with the jig to polish the lining with a grindstone to adjust the outer diameter of the lining to a predetermined diameter. In the lining polishing method, a sensor that detects the position of the lining surface of the shoe assembly assembled to the jig is provided, and polishing is performed while the position of the outer surface of the lining is detected by the sensor, and the position information of the lining from the sensor is stored in advance. The feature is that the lining outer surface position is settled within the reference range as compared with the set reference position. It is preferable to use a sensor having a contactor that comes into contact with the outer surface of the lining such as a dial gauge as the sensor. In this case, it is more preferable to dispose a plurality of contacts in the width direction of the lining and detect the inclination of the lining in the width direction.

[0006]

[Function] Since the polishing status of the lining is constantly checked by the sensor, it is not necessary to inspect each lot with a dial gauge each time as in the conventional method, and workability is improved, while at the same time excessive polishing or insufficient polishing is performed. It is possible to prevent the occurrence of defective products such as, and improve the yield.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 shows a polishing apparatus 10. 1
Reference numeral 1 denotes a rotary grindstone, which is provided on the grindstone base 12 so as to rotate at a high speed in the direction of arrow A shown in the drawing within the vertical plane. Reference numeral 13 is a table, and the rotating grindstone 1 is operated by operating the handle 14.
It is provided movably in the Y direction in the drawing, which is close to and away from the No. 1. The table 13 is arranged on a table 16 that can be moved in the X direction in the figure by operating the handle 15, and this table 16 can be moved in the Z direction (vertical direction) in the figure by operating the handle 17. Since it is arranged on the table 18, the table 13 can be moved and adjusted in each of the X, Y, and Z directions with respect to the rotary grindstone 11 by operating each of these handles.

A rotary table 19 which rotates in the direction of arrow B shown in the drawing in a horizontal plane by a rotating mechanism (not shown) is provided at a position on the table 13 substantially facing the rotary grindstone 11. As shown in FIG. 2, a shoe assembly 22 in which a lining 21 is adhered to the outer surface of an arc-shaped shoe 20 is opposed to and fixed to the turntable 19 by two tightening plates 23 so as to face each other. The rotary table 19 and the tightening plate 23 form a jig 24. Reference numeral 25 denotes a sensor made up of a dial gauge, which is provided on the table 13, and its contactor comes into elastic contact with the outer surface of the lining 21 of the shoe assembly 22 fixed by the jig 24. A current corresponding to the contact position of the contactor with the outer surface of the lining 21 is input to a comparator provided in the operation panel 26, and this comparator compares it with a reference value input in advance. .. When the lining 21 is polished by the rotary grindstone 11, the contact moves by the amount of the polishing, and the current value input to the comparator fluctuates according to this movement, and when the input value matches the reference value, the operation panel 26 The display lamp on the display panel 27 is turned on. The operation panel 26 includes a rotary grindstone 11 and a rotary base 1.
A start switch such as 9 is provided. Reference numeral 28 is a hood that covers the side surface and the upper surface of the rotary grindstone 11, and sucks and removes the polishing powder.

Explaining the polishing work, an operator first fixes the shoe assembly 22 on the table 13 with a jig 24. Then, the handles 14, 15 and 17 are operated to initialize the table 13 so that the table 13 is at a predetermined position with respect to the rotary grindstone 11. Next, the start switch is pressed to rotate the rotary grindstone 11 and the rotary table 19 to start polishing the lining. When the lining 21 is ground by a predetermined amount and the contact moves and the display lamp on the operation panel 27 is turned on, the rotary grindstone 11 and the rotary base 19 are stopped, the shoe assembly 22 is removed from the jig 24, and separately. Check the polishing status of the lining with a dial gauge or the like, and if the outer diameter of the lining is the desired value, the above initial settings are correct, so continue the polishing work of the next shoe assembly. In this continuous polishing, since the polishing state of the lining 21 is always checked, it is not necessary to inspect each lot with a dial gauge each time as in the conventional case, and workability is improved, and at the same time excessive polishing or insufficient polishing is performed. It is possible to prevent the occurrence of defective products such as the above and improve the yield. If the initial settings are not correct, the position of the table 13 and the position of the dial gauge 25 may be reset.

In the above, the indicator lamp is turned on when the polishing amount reaches the predetermined amount, and the operator stops the rotary grindstone 11, the rotary table 19 and the like, but when the polishing amount reaches the predetermined amount. Alternatively, the rotary grindstone 11 and the rotary base 19 may be automatically stopped so as to notify the end of polishing by a buzzer or the like. Further, it is preferable to automatically stop the rotary grindstone 11 and the like even when excessive polishing occurs. Further, if a timer is provided and the display lamp does not light up even after a lapse of a predetermined time after the start of polishing, it is possible that the rotary grindstone 11 is worn. FIG. 3 shows an example in which three dial gauges are arranged. In the present embodiment, the contacts of each dial gauge are brought into contact with each other in the width direction of the lining 21 at the upper part, the central part and the lower part, and the polishing condition of each part is detected. If the polishing status of each part is the same and each indicator lamp lights up almost at the same time, it is confirmed that normal polishing is being performed. If it is confirmed that the lighting status of each lamp has a predetermined variation, it is considered that the rotating grindstone 11 is unevenly distributed, and the wear status of the rotating grindstone is confirmed. As a result, the inclination of the lining 21 in the width direction can be confirmed, and polishing can be performed more accurately. Although the dial gauge having the contactor is used as the sensor in the above embodiment, a non-contact laser sensor, an infrared sensor or the like may be used.

Although the present invention has been variously described with reference to the preferred embodiments, the present invention is not limited to these embodiments, and many modifications can be made without departing from the spirit of the invention. Of course.

[0012]

As described above, according to the present invention, since the polishing is carried out while confirming the polishing state of the lining by the constant sensor during polishing, the outer diameter of the lining can be discriminated during polishing, and the work can be performed. In addition to improving productivity, product defects are eliminated and yield is improved.

[Brief description of drawings]

FIG. 1 is a perspective view of a polishing device.

FIG. 2 is a front view of a shoe assembly.

FIG. 3 is an explanatory diagram of an embodiment in which three dial gauges are arranged.

[Explanation of symbols]

 10 Polishing Device 11 Rotating Grinding Stone 13 Table 23 Jig 25 Sensor 26 Control Panel

Claims (3)

[Claims] 1. A drum for assembling a shoe assembly having a lining adhered to a shoe to a jig, rotating the shoe assembly together with the jig and polishing the lining with a grindstone to adjust the outer diameter of the lining to a predetermined diameter. In a lining polishing method for a brake shoe, a sensor is provided for detecting the position of the lining surface of the shoe assembly assembled to the jig, and polishing is performed while detecting the position of the outer surface of the lining by the sensor, and the position of the lining from the sensor. Compare the information with the preset reference position,
A method for polishing a lining of a drum brake shoe, wherein the outer surface position of the lining is set within a reference range. 2. The lining polishing method for a drum brake shoe according to claim 1, wherein a sensor having a contact for contacting an outer surface of the lining such as a dial gauge is used as the sensor. 3. The lining polishing method for a drum brake shoe according to claim 2, wherein a plurality of contacts are arranged in the width direction of the lining and the inclination of the lining in the width direction is detected.