Hitachi, Ltd.

Hitachi Automotive Systems, Ltd.

Honda Motor Co., Ltd.

Keisuke Nanri

Tomoji Sato

Junichi Nagasawa

Kimiyasu Kono

Jun Takahashi

Yoshimasa Matsui

Yuichi Kobayashi

Hidetoshi Toyoda

Masayuki Fujita

Shinichi Kuwahara

Takashi Sano

Kiyotaka Nomura

A disc brake includes a pair of end-side connector parts that connect a pair of cylinder parts across over a disc rotor, and an intermediate connector part that is installed between the end-side connector parts and that connects the pair of cylinder parts across over the disc rotor and brake pads. The brake pads are provided with protrusion segments that are formed at positions that are outer end sides in a rotor radial direction and that protrude in directions separated from middle portions of the brake pads in a rotor rotational direction, and the end-side connector parts are provided with pad engaging faces on which inner regions in the rotor radial direction of the protrusion segments are oppositely disposed and which are formed of the same member as a caliper main body.

Disc brake

A disc brake includes a caliper main body configured to have a pad assembling space that is disposed across over a disc rotor and opens toward an approximate middle thereof in a rotor radial direction and a connector part that crosses the pad assembling space in a rotor axial direction, and a pad spring that is engaged with the connector part of the caliper main body by a pair of claw portions facing each other, is installed on the caliper main body, and biases the brake pads in a rotor rotational outlet direction and inward in the rotor radial direction. The pad spring has a symmetrical shape with respect to the center in a longitudinal direction thereof, and the pair of claw portions are engaged with the connector part in a state in which the center in the longitudinal direction is offset in a rotor rotational direction with respect to the center in the rotor rotational direction of the brake pads.

A disk brake is provided which is free from problems attributed to the obverse-reverse orientation of a cover member as installed. A cylinder portion () slidably accommodating a piston is formed from a plate-shaped cover member () constituting the bottom thereof and a caliper body main part () having an opening () that is closed with the cover member (). The cover member () is joined to the caliper body main part () to close the opening (). A projection () is provided on one side of the cover member () that faces inside the cylinder portion (), and a blind hole () is provided on the other side of the cover member (). When the cover member () has been installed in the normal orientation, the blind hole () remains after the outer surface of the bottom of the caliper body has been subjected to face cutting after the installation of the cover member ().

Disk brake and method of producing the same

A disk brake having a cylinder apparatus wherein although an opening of a cylinder body is closed by a covering member, processing and parts' costs are reduced, fluid leakage is prevented, and the apparatus can be reduced in size. A piston () is caused to slidingly move in a bore () of a cylinder () of the cylinder apparatus. The cylinder () includes a covering member () provided in a bottom portion () of the cylinder (), and a cylinder body () having an opening that is closed by the covering member (). The covering member () is friction stir welded to the cylinder body ().

Cylinder apparatus and disk brake

A disk brake including: a brake pad; a piston; a cylinder bore; an annular sealing groove formed on the cylinder bore; and a rectangular piston seal fitted into the sealing groove sealing between the piston and the cylinder bore, wherein the sealing groove includes: a bottom surface portion inclined as the sealing groove expands its diameter; a lateral surface portion that extends from one end of the bottom surface portion, the one end being a side where the sealing groove has the maximum diameter; and a chamfered portion, and wherein an inclined angle of the bottom surface portion is 2 to 8 degrees, an angle between the bottom surface portion and the lateral surface portion is 82 to 89 degrees, and with the piston installed into the cylinder bore, the piston seal abuts against the bottom surface portion and the lateral surface portion of the sealing groove.

Disk brake

The bottom surface of a seal groove provided in a cylinder bore has a first slant portion and a second slant portion. A transition point between the first slant portion and the second slant portion is located closer to the opening of the cylinder bore than the center in the cylinder bore axial direction of the seal groove. A gap is formed between the outer peripheral surface of a piston seal member and the bottom surface of the seal groove, and the surface pressure applied to the bottom surface of the seal groove from the piston seal member is higher at the cylinder-bottom-side end of the piston seal member than at the cylinder-opening-side end thereof. Thus, it is possible to suppress the movement of the piston toward the cylinder bore bottom due to thermal expansion of the piston seal member.

A method of manufacturing a cylinder apparatus wherein although an opening of a cylinder body is closed by a covering member, processing and parts costs are reduced, fluid leakage is prevented, and the apparatus can be reduced in size. The cylinder apparatus includes a piston () which is caused to slidingly move in a bore () of a cylinder (). The cylinderincludes a covering member () provided in a bottom portion () of the cylinder (), and a cylinder body () having an opening that is closed by the covering member (). The covering member () is friction stir welded to the cylinder body ().

A disk brake has a flange portion formed on the outer periphery of a portion of a caliper body main body where an opening is formed. The opening is used for insertion of a cutting tool for machining of a cylinder bore. The outer diameter of the flange portion is larger than that of a general surface of the outer peripheral wall of the bore formed in the caliper body main body. A lid member is secured to the opening by friction stir welding. The flange portion ensures a sufficient welding margin. The overall weight of the disk brake is reduced by minimizing the wall thickness of the general surface of the outer peripheral wall of the bore.

A method of manufacturing a disc brake in which a pair of pads are disposed on opposite sides of a disc. A caliper body extends over the disc. The method includes forming, in the caliper body, a prepared hole for a bore into which a piston is slidably fitted and a recess extending from a bottom portion of the prepared hole outwardly in a radial direction of the prepared hole. The bore and recess are formed by means of a core during casting. A linear passage opening is formed by cutting from an exterior surface of the caliper body so as to communicate with the recess. Thus, an opening for forming a brake fluid passage can be easily formed by machining, and the position of the opening can be determined with a high degree of freedom.

Method of manufacturing a disc brake

A radially mounted disk brake has a caliper body secured to a support member secured to a vehicle body. The caliper body has mounting holes extending in a direction perpendicular to the axis of rotation of a disk rotor. Large-diameter hole portions are formed at the openings of the mounting holes on the side thereof closer to the support member. The large-diameter hole portions are fitted with the side wall surfaces of cylindrical step portions provided on the support member in such a manner that gaps are formed between the bottoms of the large-diameter hole portions and the distal end surfaces of the step portions. The center of the axial length of each mounting hole is positioned radially outward of the disk rotor in the axial direction of the mounting hole with respect to a shortest-distance portion of the caliper body at which the distance between the center of a cylinder bore and the mounting hole is shortest.

Growing community of inventors

Minami-Alps, Japan

Keisuke Nanri