JP2007147041A - Disc brake device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a disc brake device for reducing braking noises in a direct face mode or a one-circumferential-node mode. <P>SOLUTION: The disc brake device 1 thrusts brake pads 19, 20 against a disc rotor 5 to brake a vehicle. It thrusts the brake pads 19, 20 at their outer and inner periphery sides beyond an approximately center C of a slide width A, against the disc rotor 5. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a disc brake device for a vehicle.

  Disc brake devices are used to brake automobiles and railway vehicles. A disc brake device generates frictional force by pressing a disc (disc rotor) that rotates together with wheels from both sides with a brake pad, and converts kinetic energy of the vehicle into heat energy to brake the vehicle. It is known that so-called brake squeal occurs due to friction between the brake pad and the disc rotor, and various disc brake devices have been devised to reduce this brake squeal.

  A disc brake device provided with a plurality of pistons for pressing a brake pad has been proposed (see, for example, Patent Document 1). The disc brake device described in Patent Document 1 reduces uneven wear of the brake pad by pressing the brake pad vertically by a plurality of pistons, thereby reducing brake squeal.

Further, a disc brake device has been proposed in which the surface pressure distribution of the brake pad with respect to the disc rotor is set so that at least one of the inner peripheral side and the outer peripheral side in the radial direction of the disc rotor is higher than the middle part (for example, a patent Reference 2). In the disk brake device described in Patent Document 2, the surface pressure distribution in the radial direction of the disk rotor is made non-uniform so that the surface pressure on the leading side (the disk rotor entrance side with respect to the brake pad) is caused by uneven wear or thermal deformation. Even if it gets higher, we try to prevent brake noise.
Japanese Utility Model Publication No. 63-160446 JP 2004-347095 A

  By the way, a face-to-face mode is known as a mode for generating brake squeal. FIG. 1A is a diagram showing a vibration state of the disc rotor 1 when a brake squeal is generated in the perpendicular mode. The perpendicular mode is a generation mode in which nodes are generated in the circumferential direction of the disc rotor, causing the disc rotor to vibrate and causing a brake squeal. Since the disk rotor is not deformed at the nodes 1a to 1h and the disk rotor is slightly deformed between the nodes, in the perpendicular mode, the disk rotor undulates in the circumferential direction to generate brake noise. In FIG. 1A, the abdomen indicated by “+” vibrates toward the front side of the paper, the abdomen indicated by “−” vibrates toward the back side of the paper, and the hatched portion indicates a portion with relatively large deformation.

  It is said that such a brake squealing in the perpendicular mode may be achieved by increasing the surface pressure on the outer peripheral side in the radial direction of the disk rotor. However, when the surface pressure on the outer peripheral side in the radial direction of the disc rotor is increased, a brake squeal may occur due to the one-circular joint mode as shown in FIG. The one-circular joint mode is a mode for generating a brake squeal in which the disk rotor vibrates by generating a node 1k in the radial direction of the disk rotor. When the 1-circular node mode occurs, the perpendicular mode also occurs. Therefore, in FIG. 1 (b), in addition to the vibration in the perpendicular mode of FIG. 1 (a), the inner periphery side of the node 1k is the outer periphery around the node 1k. It vibrates in the opposite phase to the side.

  Therefore, in order to reduce the brake squeal, it is necessary to reduce the brake squeal in the face-to-face mode or the one-circular joint mode. However, in the disc brake device described in Patent Document 1 or Patent Document 2, these brakes Cannot effectively suppress squeal.

  In view of the above problems, an object of the present invention is to provide a disc brake device that reduces brake squealing in a face-to-face mode or a one-circle mode.

  In order to solve the above-described problems, the present invention provides a disc brake device that brakes a vehicle by pressing a brake pad against a disc rotor, and is provided on an outer peripheral side and an inner peripheral side with respect to a substantially center of a sliding width of the brake pad relative to the disc rotor. Each is characterized in that a brake pad is pressed.

  According to the present invention, it is possible to reduce brake squeal in the face-straight mode and the one-circular joint mode by pressing the outer peripheral side and the inner peripheral side with the brake pads.

  More preferably, the disc brake device presses the brake pad including substantially the center of the sliding width. Since the approximate center of the sliding width is pressed at a plurality of locations, the braking force is increased and brake noise can be reduced.

  Moreover, in one form of this invention, it has the 1st piston which presses the outer peripheral side of a brake pad, and the 2nd piston which presses the inner peripheral side of a brake pad, It is characterized by the above-mentioned.

  According to the present invention, since the first piston presses the outer peripheral side and the second piston presses the inner peripheral side, the brake squeal in the plane mode and the one-circular joint mode can be reduced.

  Further, in one embodiment of the present invention, a shim is interposed between the brake pad and a piston that presses the brake pad, and the shim is on the leading side from the substantially half on the trailing side and the half on the outer circumferential side. Each of the shims has a notch, or the shim has a notch on the leading side from the approximately half on the inner peripheral side and a notch on the trailing side from the approximately half on the outer peripheral side.

  According to the present invention, since the shim has cutouts on the inner and outer peripheral sides, the inner and outer peripheral sides of the disk rotor can be pressed, respectively, and braking in the plane mode and the one-circular joint mode is possible. The noise can be reduced.

  It is possible to provide a disc brake device that reduces brake squeal in the face-to-face mode or the one-circle mode.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

  FIG. 2 is a front view of the disc brake device according to the present embodiment as viewed from the outer side. FIG. 3 is a cross-sectional view taken along line AA in FIG. The disc brake device of FIGS. 2 and 3 is a counter-type disc brake device, and has pistons 10a and 10b on the inner side and pistons 11a and 11b on the outer side.

  The disc brake device 1 includes a disc-like disc rotor 5 that rotates integrally with a wheel, a brake pad having an inner pad 19 and an outer pad 20 that are disposed to face each other with the disc rotor 5 interposed therebetween, and straddles the outer peripheral edge of the disc rotor 5. A caliper 2 is provided.

  The caliper 2 has, on the inner side, a cylinder 11a and a piston 11a that slides in the cylinder 13a, and a cylinder 11b and a piston 11b that slides in the cylinder 13b. The caliper 2 has, on the outer side, a cylinder 12a and a piston 10a that slides in the cylinder 12a, and a piston 10b that slides in the cylinder 12b and the cylinder 12b.

  The pistons 11 a and 11 b are linked to the inner pad 20, and the pistons 10 a and 10 b are linked to the outer pad 19.

  The caliper 2 includes a brake fluid oil chamber 15a for pushing the piston 11a and a brake fluid oil chamber 15b for pushing the piston 11b on the inner side, and an oil inlet 17 communicates with the oil chamber 15b. The oil chambers 15a and 15b communicate with each other through a communication path.

  Similarly, the caliper 2 includes a brake fluid oil chamber 16a for pushing the piston 10a and a brake fluid oil chamber 16b for pushing the piston 10b on the outer side, and an oil inlet 18 communicates with the oil chamber 16a. ing. The oil chambers 16a and 16b communicate with each other through a communication path 16c.

  Brake hoses are connected to the oil inlet 17 and the oil inlet 18, respectively, and brake fluid flows into the oil chambers 15b and 16a during braking. The brake fluid that has flowed into the oil chamber 15b flows through the communication path and flows into the oil chamber 15a, and the brake fluid that flows into the oil chamber 16a flows through the communication path and flows into the oil chamber 16b.

  The inner pad 20 is composed of the friction material 7 and a back metal 9 that holds the friction material 7. The outer pad 19 is constituted by the friction material 6 and a back metal 8 that holds the friction material 6.

  The arrangement of the piston will be described. Since the outer pad 19 and the inner pad 20 slide on the disk rotor 5 during braking, a sliding width A is formed. The sliding width A is, for example, the length from the outer edge of the disk rotor 5 to the end of the friction material 7 or 6 in the short direction.

  In this embodiment, the cylinder center of the piston 10a is arranged in the outer circumferential direction with respect to the center C of the sliding width A, and the cylinder center of the piston 10b is arranged in the inner circumferential direction with respect to the center C of the sliding width A. . The opposed inner piston 11 a is configured such that its cylindrical center is substantially opposed to the piston 10 a via the disk rotor 5, and the piston 11 b is substantially opposed to the piston 10 b via the disk rotor 5. Configured to do.

  The piston 10a and the piston 10b form a pressing surface so that at least one of them includes the center C of the sliding width A.

  In the disc brake device 1 configured as described above, when the brake fluid is supplied to each oil chamber, the pistons 11a and 11b and the pistons 10a and 10b are pushed, and the inner pad 20 and the outer pad 19 are connected to the disc rotor. By holding 5, the vehicle is braked.

  In the disc brake device 1 of the present embodiment, since the pistons 10a and 11a press the outer peripheral side of the center C of the sliding width A during braking, the vibration in the perpendicular mode occurring near the outer periphery can be effectively suppressed. . Further, since the pistons 10b and 11b press the inner peripheral side with respect to the center C of the sliding width A, it is possible to effectively suppress the vibration of the one-circular joint mode generated in the vicinity of the inner periphery. Therefore, it is possible to reduce the brake squeal that is generated by the coupling of the plane mode and the one-circular joint mode and the one-circular joint mode and another vibration mode.

  In FIG. 2, the cylinder 10a on the trailing side (the inlet side of the disc rotor 5 with respect to the inner pad) is arranged on the outer peripheral side, and the cylinder 10b on the leading side (the outlet side of the disc rotor 5 with respect to the inner pad) is arranged on the inner peripheral side. However, the trailing cylinder 10a may be disposed on the inner circumferential side and the leading cylinder 10b may be disposed on the outer circumferential direction. Moreover, as shown in FIG. 4, the number of pistons may differ on the outer peripheral side and the inner peripheral side. In FIG. 4, two pistons 21a and 21b are arranged on the outer peripheral side, and one piston 21c is arranged on the inner peripheral side. In addition, each oil chamber of piston 21a-21c is connected. The cylindrical centers of the pistons 21a and 21b are on the outer peripheral side with respect to the center C of the sliding width A, and the cylindrical center of the piston 21c is on the inner peripheral side with respect to the center C of the sliding width A. Inner pistons are arranged at positions facing the respective pistons.

  During braking, the pistons 21a and 21b are opposed to the piston C and the piston C opposed to the center C of the sliding width A, and the piston opposed to the piston 21c is urged to the inner circumference of the sliding width A from the center C. . Therefore, it is possible to reduce the brake squeal that is generated by the coupling of the plane mode and the one-circular joint mode and the one-circular joint mode and another vibration mode.

  The number of pistons in the inner circumferential direction may be larger than that in the outer circumferential direction, and the number of pistons in the outer circumferential direction or the inner circumferential direction may be three or more.

  Further, while FIG. 2 has been described based on the opposed type disc brake device in which the pistons are respectively arranged on the inner side and the outer side, this embodiment also applies to the disc brake device 1 of a floating caliper having a piston only on the inner side. The arrangement of the piston can be suitably applied.

  The disc brake device of the present embodiment presses the outer peripheral side and the inner peripheral side of the center C of the sliding width A in order to reduce the perpendicular mode and the one-circular joint mode. As a configuration for this purpose, in the first embodiment, pistons are provided on the outer peripheral side and the inner peripheral side of the center C of the sliding width A, respectively, but in this embodiment, the outer peripheral side and the inner peripheral side of the center C of the sliding width A by shims. Respectively.

  FIG. 5 shows a front view of the disc brake device as viewed from the outer side in the present embodiment. 6 shows a cross-sectional view taken along line BB of FIG. In FIG. 5 or FIG. 6, the same components as those in FIG. 2 or FIG.

  The disc brake device 1 of this embodiment is different from that of the first embodiment in that the pistons 31a and 31b have their cylindrical centers arranged at positions that are not biased with respect to the center C of the sliding width A. Inner side pistons 34a and 34b are arranged at positions facing the piston 31a and the piston 31b via the disk rotor 5, respectively.

  Further, the disc brake device 1 of this embodiment includes a shim 35 between the inner side pistons 34 a and 34 b and the inner pad 20, and a shim 30 between the outer side pistons 31 a and 31 b and the inner pad 19.

  The shim has a vibration damping effect of the brake pad or the disc rotor 5 during braking. The shim is a metal plate such as stainless steel and is applied to the back surface of the inner pad 20 or the outer pad 19. In order to obtain a greater vibration damping effect, rubber coating may be applied, or a shim in which a metal shim and rubber are stacked may be used. Although only the outer side shim 30 is shown in FIG. 5, the shim 35 has the same shape as seen in a plan view from the outer side.

  The shims 30 and 35 of this embodiment are obtained by cutting out a part of the longitudinal direction of the shim having a longitudinal direction in the circumferential direction. In FIG. 5, the outer peripheral side on the trailing side from approximately half in the longitudinal direction and the inner peripheral side on the leading side from approximately half in the longitudinal direction are cut out in a rectangular shape. The same applies to the inner shim 35.

  The shims 30 and 35 form a pressing surface so that at least one of them includes the center C of the sliding width A.

  If it is the shape of the shim shown in FIG. 5, as shown in FIG. 6, the piston 31b and the piston 34b will pinch the disk rotor 5 through the shim with the inner peripheral side cut away. On the other hand, the piston 31a and the piston 34a sandwich the disk rotor 5 through a shim with the outer peripheral side cut out.

  In the disc brake device 1 configured as described above, when the brake fluid is supplied to each oil chamber, the pistons 31a and 31b and the pistons 34a and 34b are respectively pushed, and the inner pad 20 and the outer pad 19 are connected to the disc rotor. By holding 5, the vehicle is braked.

  In the disc brake device 1 of the present embodiment, the inner pad 20 and the outer pad 19 are entirely pressed against the disc rotor 5 at the time of braking, but the pressure of the portions where the shims 30 and 35 are not cut out is cut out. It becomes stronger than the part. That is, on the leading side, the outer peripheral side of the center C of the sliding width A is pressed more strongly than the inner peripheral side by the pistons 31b and 34b, and the vibration in the perpendicular mode that occurs near the outer periphery can be effectively suppressed. Further, on the trailing side, the inner peripheral side of the center C of the sliding width A is pressed more strongly than the outer peripheral side by the pistons 31a and 34a, and the vibration of the one-circular joint mode generated in the vicinity of the inner periphery is effectively performed. Can be suppressed. Therefore, it is possible to reduce the brake squeal generated by the coupling of the perpendicular mode and the one-circular joint mode and the one-circular joint mode and another vibration mode.

  In FIG. 5, the outer peripheral side of the trailing shim is cut out and the inner peripheral side of the leading shim is cut out, but the inner peripheral side of the trailing shim is cut out and the outer peripheral side of the leading shim May be cut off.

  Further, in this embodiment, the cylinder center of the piston is arranged so as not to be biased with respect to the center line C. However, as shown in FIG. 7A, the cylinder center of the piston is arranged on the side without the shim notch. May be. That is, the leading piston is disposed on the outer peripheral side, and the trailing piston is disposed on the inner peripheral side. By arranging the shim and the piston as shown in FIG. 7A, the outer peripheral side and the inner peripheral side of the disc rotor can be pressed more strongly, and the brake squeal in the face-to-face mode and the one-circular joint mode can be generated. Can be reduced.

  Moreover, as shown in FIG.7 (b), you may press the shim which has a notch on the inner peripheral side and outer peripheral side with one piston. With the configuration as shown in FIG. 7B, the pressure at the shim-attached portions (inner peripheral side and outer peripheral side) increases, so that brake squeal in the face-to-face mode and the one-circular joint mode can be reduced. Further, the cost can be reduced because only one piston is required.

  The cutouts of the shims 30 and 35 do not have to be rectangular, and may be semicircular or U-shaped. The shim cutout of the present embodiment is such that the approximate center of the remaining shim area on the trailing side and the leading side is closer to the outer peripheral side and the inner peripheral side than the center C of the sliding width A. What is necessary is just to be biased.

  In FIG. 4, the description has been made based on the opposed type disc brake device in which the pistons are arranged on the inner side and the outer side, respectively. However, even in the floating caliper disc brake device 1 having the piston only on the inner side, the present embodiment. The shim can be suitably applied.

  As described above, in the disc brake device according to the present embodiment, it is possible to reduce brake squeal in the face-to-face mode and the one-circular joint mode.

It is a figure which shows the generation | occurrence | production mode of the brake squeal by the face-straight mode and 1-circle mode. It is the front view seen from the outer side of the disc brake device in Example 1. FIG. 3 is a sectional view taken along line AA in FIG. 2. It is a top view of the disc brake from which the number of pistons differs in the outer peripheral side and the inner peripheral side. It is the front view seen from the outer side of the disc brake device in Example 2. FIG. 6 is a sectional view taken along line BB in FIG. 5. In Example 2, it is a figure which shows the modification of arrangement | positioning of a piston.

Explanation of symbols

1 Disc brake device
5 Disc rotor 10a, 10b, 11a, 11b, 31a, 31b, 34a, 34b Piston 19 Outer pad 20 Inner pad 30, 35 Shim

Claims (4)

In a disc brake device that brakes a vehicle by pressing a brake pad against a disc rotor,
Each of the outer peripheral side and the inner peripheral side of the brake pad with respect to the disc rotor is pressed from the substantially center of the sliding width, and the brake pad is pressed.
A disc brake device characterized by that.   The disc brake device according to claim 1, wherein the brake pad is pressed including substantially the center of the sliding width. A first piston that presses the outer peripheral side of the brake pad;
A second piston that presses the inner peripheral side of the brake pad;
The disc brake device according to claim 1, wherein: A shim interposed between the brake pad and a piston that presses the brake pad;
The shim has a notch on the trailing side from the approximately half on the inner peripheral side and the leading side from the approximately half on the outer peripheral side, or
The shim has a notch on the leading side from the approximately half on the inner peripheral side and on the trailing side from the approximately half on the outer peripheral side,
3. The disc brake device according to claim 1, wherein the disc brake device is a disc brake device.

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