Brake hydraulic pressure controller

A brake hydraulic pressure controller (20) configured to control a hydraulic pressure in a brake hydraulic pressure circuit, the brake hydraulic pressure controller (20) comprising:

• a housing (130) having therein a channel (111b, 113b),
• a motor (96) that has a motor shaft (96a);
• a skew plate (125) that is fixed to a tip of the motor shaft (96a) and is arranged in a manner to be inclined with respect to an axial direction of the motor shaft (96a);
• and
• a pump element (44) that is driven by rotation of the motor shaft (96a) and the skew plate (125), the pump element (44) being arranged in the housing (130), wherein
• the pump element (44) has:
• a piston (150) that reciprocates in parallel with the axial direction of the motor shaft (96a) in conjunction with the rotation of the skew plate (125);
• an accommodation chamber (161) that accommodates a part of the piston (150) and into which a brake fluid is introduced;
• a suction valve (170) that introduces the brake fluid into the accommodation chamber (161);
• a release valve (180) that releases the brake fluid from the accommodation chamber (161);
• and
• a sleeve (191) defining a pressure damper chamber (190) that is provided in a reciprocal direction of the piston (150) and into which the brake fluid released from the release valve (180) flows, the sleeve (191) being positioned in the housing (130),
• wherein the sleeve (191) has an open end fitted to the release valve (180), a closed end opposite the open end, and a wall which extends from the open end of the sleeve (191) to the closed end of the sleeve (191) and which surrounds the pressure damper chamber (190), the wall having therein a through hole (193) through which the brake fluid is released from the pressure damper chamber (190) to the channel (111b, 113b),
• wherein an accommodation member (161) defines the accommodation chamber (160) and includes a tapered hole (163) which communicates with the accommodation chamber (161) and which is formed as a seat section, wherein the release valve (180) includes a valve body (181), a support member (185) having a through hole (187), and a spring (183) which is held in a compressed state between the support member (185) and the valve body (181) and which urges the valve body (181) toward the seat section, wherein the open end of the sleeve (191) is fitted on the support member (185) such that the pressure damper chamber (190) communicates with the through hole (187) of the support member (185), wherein, when the valve body (181) is moved away from the seat section, the brake fluid is released from the accommodation chamber (161) through the through hole (163) of the accommodation member (161) and is delivered to the pressure damper chamber (190) through the through hole (187) of the support member (185),
• wherein the pump element (44) is accommodated in an accommodation hole (131a, 131b) that is formed in the housing (130), a cylindrical inner surface of the housing (130) defining the accommodation hole (131a, 131b),
• wherein the open end of the sleeve (191) engages a shoulder on the support member (185) and the wall of the sleeve (191) has a cylindrical outer surface extending from the open end of the sleeve (191), and
• wherein the cylindrical outer surface of the sleeve (191) is spaced from the cylindrical inner surface of the housing (130).

A brake hydraulic pressure controller (20) configured to control a hydraulic pressure in a brake hydraulic pressure circuit, the brake hydraulic pressure controller (20) comprising:

• a housing (130) having therein a channel (111b, 113b),
• a motor (96) that has a motor shaft (96a);
• a skew plate (125) that is fixed to a tip of the motor shaft (96a) and is arranged in a manner to be inclined with respect to an axial direction of the motor shaft (96a);
• and
• a pump element (44) that is driven by rotation of the motor shaft (96a) and the skew plate (125), the pump element (44) being arranged in the housing (130), wherein
• the pump element (44) has:
• a piston (150) that reciprocates in parallel with the axial direction of the motor shaft (96a) in conjunction with the rotation of the skew plate (125);
• an accommodation chamber (161) that accommodates a part of the piston (150) and into which a brake fluid is introduced;
• a suction valve (170) that introduces the brake fluid into the accommodation chamber (161);
• a release valve (180) that releases the brake fluid from the accommodation chamber (161);
• and
• a sleeve (191) defining a pressure damper chamber (190) that is provided in a reciprocal direction of the piston (150) and into which the brake fluid released from the release valve (180) flows, the sleeve (191) being positioned in the housing (130),
• wherein the sleeve (191) has an open end fitted to the release valve (180), a closed end opposite the open end, and a wall which extends from the open end of the sleeve (191) to the closed end of the sleeve (191) and which surrounds the pressure damper chamber (190), the wall having therein a through hole (193) through which the brake fluid is released from the pressure damper chamber (190) to the channel (111b, 113b),
• wherein an accommodation member (161) defines the accommodation chamber (160) and includes a tapered hole (163) which communicates with the accommodation chamber (161) and which is formed as a seat section, wherein the release valve (180) includes a valve body (181), a support member (185) having a through hole (187), and a spring (183) which is held in a compressed state between the support member (185) and the valve body (181) and which urges the valve body (181) toward the seat section, wherein the open end of the sleeve (191) is fitted on the support member (185) such that the pressure damper chamber (190) communicates with the through hole (187) of the support member (185), wherein, when the valve body (181) is moved away from the seat section, the brake fluid is released from the accommodation chamber (161) through the through hole (163) of the accommodation member (161) and is delivered to the pressure damper chamber (190) through the through hole (187) of the support member (185),
• wherein the open end of the sleeve (191) engages a shoulder on the support member (185) and the wall of the sleeve (191) has a cylindrical inner surface extending from the open end of the sleeve (191), the cylindrical inner surface surrounding and engaging an outer surface of the support member (185) extending from the shoulder toward the closed end of the sleeve (191), and the wall of the sleeve (191) has a cylindrical outer surface extending from the open end of the sleeve (191), and
• wherein the pump element (44) is accommodated in an accommodation hole (131a, 131b) in the housing (130) and the cylindrical outer surface of the sleeve (191) is spaced from a cylindrical inner surface of the housing (130), the inner cylindrical surface defining the accommodation hole (131a, 131b).