JP4417187B2 - Master cylinder - Google Patents

Description

  The present invention relates to a master cylinder capable of reducing costs.

Some master cylinders include a cylinder body, a piston that is slidable on the cylinder body and forms a pressure chamber with the cylinder body, and a piston spring that is disposed in the pressure chamber and biases the piston. . In such a master cylinder, in order to make it easy to dispose the piston spring in the pressure chamber with a predetermined set length, a spring retainer having a predetermined set length by locking both ends while allowing the contraction of the piston spring. (For example, refer to Patent Document 1).
Japanese Utility Model Publication No. 6-83529

  The above-described spring retainer of Patent Document 1 includes two divided bodies, and these divided bodies need to engage the end portions of the piston springs at one end side and engage the other end sides so as to be movable relative to each other. For this reason, one of the divided bodies has a large diameter at the intermediate portion, and the other divided body has a small diameter at the intermediate portion. Thus, since the division body of a different shape must be manufactured, there existed a problem that a number of parts would be large and manufacturing cost and management cost would increase.

  Therefore, an object of the present invention is to provide a master cylinder capable of reducing manufacturing costs and management costs.

  In order to achieve the above object, an invention according to claim 1 is provided in a cylinder main body, a piston slidably provided on the cylinder main body and forming a pressure chamber with the cylinder main body, and the pressure chamber. In the master cylinder having a piston spring that urges the piston and a spring retainer that engages both ends of the piston spring while allowing expansion and contraction of the piston spring, one end side of the spring retainer is an end of the piston spring. The other end side is formed of a pair of same-shaped divided bodies that are engaged with each other so as to be movable in the axial direction of the piston spring.

  The invention according to claim 2 is the invention according to claim 1, wherein the divided body includes a flange portion that locks an end portion of the piston spring, and an extension direction extending from the flange portion toward a tip end side. What is the first disposition portion formed with a claw portion protruding in a different direction and the first disposition portion at a circumferential position different from the first disposition portion extending from the flange portion? And a second disposing portion formed with a locking portion that extends from different radial positions and is locked so that the claw portion is movable in the axial direction. Engaging the claw portion of the other divided body with the claw portion of the other divided body, and engaging the claw portion of the other divided body with the locking portion of the one divided body. It is a feature.

  According to a third aspect of the present invention, in the first aspect of the invention, the divided body includes a flange portion that locks the end portion of the piston spring, and extends from the flange portion and protrudes toward the center axis on the distal end side. The outer arrangement part in which the inner claw part is formed and a position different from the outer arrangement part of the flange part and extend from the central axis side than the outer arrangement part, and are opposite to the central axis on the tip side. And an inner disposition portion formed with an outer claw portion projecting to the side, the inner claw portion of one of the divided bodies is engaged with the outer claw portion of the other divided body, and the one The inner claw portion of the other divided body is engaged with the outer claw portion of the other divided body.

  According to the first aspect of the present invention, the spring retainer has a pair of identically shaped divisions in which one end side engages the end of the piston spring and the other end is engaged with each other so as to be movable in the axial direction of the piston spring. Since it consists of a body, it is only necessary to manufacture and manage one type of divided body. Therefore, manufacturing cost and management cost can be reduced.

  According to the second aspect of the present invention, the claw portion formed in the first arrangement portion of the one divided body has a circumferential position different from that of the first arrangement portion of the other divided body and the first portion. The engaging portion formed in the second disposing portion of one of the divided bodies is engaged with the engaging portion formed in the second disposing portion provided at the radial position different from the disposing portion. By engaging the claw portion formed in the first disposition portion of the other divided body, the spring retainer locks the end portion of the piston spring with the flange portion on one end side and the other end side mutually. The piston spring is engaged so as to be movable in the axial direction. Thus, since a pair of division body can be made into a simple structure, manufacturing cost can be reduced further.

  According to the invention according to claim 3, the inner claw portion formed in the outer arrangement portion of one of the divided bodies has the inner arrangement portion provided on the center axis side than the outer arrangement portion of the other divided body. The outer claw portion formed on the first divided body is engaged, and the outer claw portion formed on the inner arrangement portion of one divided body is engaged with the inner claw portion formed on the outer arrangement portion of the other divided body. Thus, the spring retainer is engaged with the end portion of the piston spring by the flange portion at one end side, and the other end side is engaged with each other so as to be movable in the axial direction of the piston spring. Thus, since a pair of division body can be made into a simple structure, manufacturing cost can be reduced further.

  A master cylinder according to an embodiment of the present invention will be described with reference to the drawings.

  Reference numeral 11 in FIG. 1 denotes a master cylinder of the present embodiment that generates brake fluid pressure with a force corresponding to an operation amount of a brake pedal introduced via a brake booster (not shown). Is provided with a reservoir R (only part of which is shown in FIG. 1) for supplying and discharging brake fluid.

  The master cylinder 11 is formed by processing a single material into a bottomed cylindrical shape having a bottom portion 13 and a cylindrical portion 14 and is disposed in the vehicle in a posture along the lateral direction, and the cylinder main body 15. A tandem type piston having a primary piston (piston) 18 slidably inserted into the opening 16 side and a secondary piston 19 slidably inserted into the bottom 13 side of the primary piston 18 of the cylinder body 15. Is. The primary piston 18 and the secondary piston 19 are slidably guided by a sliding inner diameter portion 20 having a circular cross section perpendicular to the central axis (hereinafter referred to as a cylinder shaft) of the cylindrical portion 14 of the cylinder body 15. .

  The cylinder body 15 is formed with a locking projection 21 that protrudes in the cylinder axial direction inside the bottom portion 13.

  The cylinder body 15 has a pair of mounting bosses 22 and 23 that protrude outward in the radial direction of the cylindrical portion 14 (hereinafter referred to as the cylinder radial direction) and are spaced apart in the cylinder axial direction. Hereinafter, the mounting holes 24 and 25 for attaching the reservoir R to the mounting boss portions 22 and 23 are formed at predetermined positions in the circumferential direction of the cylinder portion 14. Are formed to match. Here, the mounting seals 26 and 27 for fitting the reservoir R and sealing the gap with the reservoir R are fitted inside the mounting holes 24 and 25.

  The sliding inner diameter portion 20 of the cylinder body 15 includes a plurality of, specifically, four annular seal circumferential grooves 30, seal circumferential grooves 31, and seal circumferential grooves 32 that are recessed outward in the cylinder radial direction by shifting positions in the cylinder axial direction. The seal circumferential groove 33 is formed in order from the bottom 13 side.

  The seal circumferential groove 30 on the most bottom 13 side of the cylinder body 15 is formed close to the mounting hole 24 on the bottom 13 side, and a piston seal 35 is fitted in the seal circumferential groove 30. The piston seal 35 is a cup seal having a C-shaped cross section, and is attached to the seal circumferential groove 30 in a state where the opening side of the C-shaped cross section is disposed on the bottom 13 side.

  The sliding inner diameter of the cylinder portion 14 is such that a communication hole 36 drilled from the mounting hole 24 on the bottom portion 13 side is opened in the cylinder portion 14 on the opening portion 16 side of the seal body groove 30 in the cylinder body 15. An annular opening groove 37 that is recessed from the portion 20 to the outside in the cylinder radial direction is formed. Here, the opening groove 37 and the communication hole 36 mainly constitute a secondary supply path 38 that connects the cylinder body 15 and the reservoir R so that they can communicate with each other and always communicates with the reservoir R.

  The sliding inner diameter portion 20 of the cylinder body 15 has an eccentric groove portion in which a part on the mounting boss portion 22 side in the cylinder circumferential direction extends from the seal circumferential groove 30 side toward the bottom 13 side while communicating with the seal circumferential groove 30. 41 is formed to be recessed outward in the cylinder radial direction.

  In the cylinder body 15, a seal circumferential groove 31 is formed on the side opposite to the seal circumferential groove 30 of the opening groove 37 in the cylinder axial direction, that is, on the opening 16 side. Is fitted. The partition seal 40 is also a cup seal having a C-shaped cross section, and is attached to the seal circumferential groove 31 in a state where the opening side of the C-shaped cross section is arranged on the opening 16 side.

  An eccentric groove portion 42 in which a part of the mounting boss portion 23 side in the cylinder circumferential direction communicates with the seal circumferential groove 32 is provided on the opening 16 side of the sliding inner diameter portion 20 of the cylinder body 15 in the cylinder circumferential direction. It is formed so as to be recessed outward in the radial direction.

  A seal circumferential groove 32 is formed closer to the opening 16 than the eccentric groove 42 in the cylinder body 15, and a piston seal 45 is fitted into the seal circumferential groove 32. The piston seal 45 is a cup seal having a C-shaped cross section, and is attached to the seal circumferential groove 32 in a state where the opening side of the C-shaped cross section is disposed on the bottom 13 side.

  The cylinder portion 14 is slid so that a communication hole 46 formed from the mounting hole 25 on the opening portion 16 side is opened in the cylinder portion 14 on the opening portion 16 side of the seal circumferential groove 32 in the cylinder body 15. An annular opening groove 47 is formed that is recessed from the inner diameter portion 20 to the outside in the cylinder radial direction. Here, the opening groove 47 and the communication hole 46 mainly constitute a primary supply path 48 that connects the cylinder body 15 and the reservoir R so that they can communicate with each other and always communicates with the reservoir R.

  A seal circumferential groove 33 is formed on the cylinder body 15 on the opposite side of the opening groove 47 with respect to the seal circumferential groove 32, that is, on the opening 16 side, and a partition seal 50 is fitted in the seal circumferential groove 33. The partition seal 50 is also a cup seal having a C-shaped cross section, and is attached to the seal circumferential groove 33 in a state where the opening side of the C-shaped cross section is disposed on the bottom 13 side.

  A secondary discharge passage 52 and a primary discharge passage 53 to which a brake pipe (not shown) for supplying brake fluid to a brake device (not shown) is attached are formed on the side of the cylinder portion 14 of the cylinder body 15. Note that the secondary discharge path 52 and the primary discharge path 53 are formed by shifting the positions in the cylinder axial direction in a state where the positions in the circumferential direction of the cylindrical portion 14 are matched. One secondary discharge path 52 is formed between the bottom 13 and the seal circumferential groove 30 and in the vicinity of the bottom 13, and the other primary discharge path 53 is formed of the seal circumferential groove 31 in the eccentric groove 42. It is formed at a position that becomes the vicinity.

  The secondary piston 19 fitted to the bottom portion 13 side of the cylinder body 15 has a bottomed cylindrical shape having a cylindrical portion 55 and a bottom portion 56 formed on one side in the axial direction of the cylindrical portion 55. The cylinder portion 55 is slidably fitted to the sliding inner diameter portion 20 of the cylinder body 15 in a state where the cylinder portion 55 is disposed on the bottom 13 side of the cylinder body 15. An annular stepped portion 59 having a slightly smaller diameter than the other portions is formed on the outer peripheral side of the end portion opposite to the bottom portion 56 of the cylindrical portion 55. In addition, the step portion 59 of the cylindrical portion 55 is formed with a plurality of radially extending ports 60 penetrating in the cylinder radial direction on the bottom portion 56 side.

  The bottom portion 56 of the secondary piston 19 is formed with a locking projection 61 that protrudes toward the primary piston 18 along the cylinder axial direction at the radial center position.

  Here, the portion surrounded by the bottom portion 13 of the cylinder body 15 and the bottom portion 13 side of the cylinder portion 14 and the secondary piston 19 is a secondary pressure chamber 63 that supplies hydraulic pressure to the secondary discharge passage 52 (in other words, The secondary piston 19 slidably provided in the cylinder body 15 forms a secondary pressure chamber 63 with the cylinder body 15). The secondary pressure chamber 63 communicates with the secondary supply path 38 when the secondary piston 19 is in a position for opening the port 60 into the opening groove 37. On the other hand, the piston seal 35 provided in the seal circumferential groove 30 on the bottom 13 side of the cylinder body 15 is in sliding contact with the outer peripheral side of the secondary piston 19. As a result, in the state where the secondary piston 19 positions the port 60 on the bottom 13 side with respect to the piston seal 35, it is possible to seal between the secondary supply path 38 and the secondary pressure chamber 63, that is, the secondary pressure chamber 63 and the secondary pressure chamber 63 The communication with the supply path 38 and the reservoir R can be blocked. Here, the piston seal 35 blocks communication between the secondary pressure chamber 63, the secondary supply path 38, and the reservoir R when the hydraulic pressure in the secondary pressure chamber 63 becomes larger than the hydraulic pressure in the secondary supply path 38 (that is, atmospheric pressure). On the other hand, when the hydraulic pressure in the secondary pressure chamber 63 becomes smaller than the hydraulic pressure in the secondary supply path 38, the secondary pressure chamber 63, the secondary supply path 38, and the reservoir R are communicated to supply liquid to the secondary pressure chamber 63.

  An initial state in which there is no input from the brake pedal side (the right side in FIG. 1) between the secondary piston 19 and the bottom 13 of the cylinder body 15, that is, the secondary pressure chamber 63 (the positions of the respective parts at this time are defined as initial positions). A piston spring 65 is provided which determines these intervals in the following and urges the secondary piston 19 to return the secondary piston 19 when the secondary piston 19 moves toward the bottom 13 of the cylinder body 15. The piston spring 65 is provided with a spring retainer 100 that locks both ends while allowing expansion and contraction to determine a set length (extension direction limit length) (details will be described later). The piston spring 65 is positioned in the cylinder radial direction by disposing the locking projection 21 of the cylinder bottom 13 inside the spring retainer 100 that locks the piston spring 65 at one end, and the cylindrical portion 55 of the secondary piston 19 at the other end. Through the inside, it is brought into contact with the bottom portion 56 via a spring retainer 100.

  The primary piston 18 fitted to the opening 16 side of the cylinder body 15 includes a first cylindrical portion 67, a bottom portion 68 formed on one side in the axial direction of the first cylindrical portion 67, and a first cylinder of the bottom portion 68. It has a shape having a second cylindrical portion 69 formed on the opposite side to the portion 67, and is inserted into the cylinder body 15 in a state where the first cylindrical portion 67 is disposed on the secondary piston 19 side in the cylinder body 15. Has been. Here, an output shaft of a brake booster (not shown) is inserted inside the second cylindrical portion 69, and this output shaft presses the bottom portion 68.

  On the outer peripheral side of the end opposite to the bottom 68 of the first cylindrical portion 67, an annular recess 73 having a slightly smaller diameter than the other portions is formed. Furthermore, a plurality of ports 74 are formed radially in the recess 73 of the first cylindrical portion 67 so as to penetrate the bottom portion 68 in the radial direction.

  Here, a portion surrounded by the opening 16 side of the cylinder portion 14 of the cylinder body 15, the primary piston 18 and the secondary piston 19 is a primary pressure chamber 76 for supplying hydraulic pressure to the primary discharge passage 53 ( In other words, the primary piston 18 slidably provided in the cylinder body 15 forms a primary pressure chamber 76 with the secondary piston 19 and the cylinder body 15), and the primary piston 18 opens the port 74. When in a position to be opened in the groove 47, it communicates with the primary supply path 48. On the other hand, the piston seal 45 provided in the seal circumferential groove 32 of the cylinder body 15 has an inner circumference that is in sliding contact with the outer circumference side of the primary piston 18, and the primary piston 18 connects the port 74 to the bottom 13 side of the piston seal 45. In a state where the primary supply passage 48 and the primary pressure chamber 76 are sealed, the primary supply chamber 48 can be blocked from communicating with the primary supply passage 48 and the reservoir R. Here, when the hydraulic pressure in the primary pressure chamber 76 becomes higher than the hydraulic pressure in the primary supply path 48 (that is, atmospheric pressure), the piston seal 45 blocks communication between the primary pressure chamber 76 and the primary supply path 48 and the reservoir R. On the other hand, when the hydraulic pressure in the primary pressure chamber 76 becomes smaller than the hydraulic pressure in the primary supply path 48, the primary pressure chamber 76, the primary supply path 48, and the reservoir R are communicated to supply the primary pressure chamber 76 with liquid.

  The partition seal 40 provided in the seal circumferential groove 31 is in sliding contact with the secondary piston 19 to seal between the secondary supply path 38 and the primary pressure chamber 76, and the partition seal 50 provided in the seal circumferential groove 33. Slidably contacts the primary piston 18 to seal the primary replenishment passage 48 against the outside air.

  The interval between the secondary piston 19 and the primary piston 18, that is, the primary pressure chamber 76, is determined in an initial state in which there is no input from the brake pedal side (the right side in FIG. 1) (not shown). A piston spring 78 is provided for biasing in a direction to return the side when it moves relative to the side. The piston spring 78 is provided with a spring retainer 101 that determines the set length (extension direction limit length) by locking both ends while allowing the contraction thereof (details will be described later). The piston spring 78 is positioned in the cylinder radial direction by disposing the locking projection 61 of the secondary piston 19 inside the spring retainer 101 that locks the piston spring 78 at one end, and the other end is the first cylinder of the primary piston 18. It passes through the part 67 and is brought into contact with the bottom part 68 via a spring retainer 101.

  Next, the spring retainer 100 for the secondary-side piston spring 65 and the spring retainer 101 for the primary-side piston spring 78 will be further described. The spring retainer 100 for the piston spring 65 is sized according to the piston spring 65, and the spring retainer 101 for the piston spring 78 is sized according to the piston spring 78. There is no.

  The spring retainer 100 includes a pair of identically shaped divided bodies 103 that engage the end of the piston spring 65 at one end and are engaged with the other end so as to be movable in the axial direction of the piston spring 65. The spring retainer 101 also includes a pair of identically shaped divided bodies 103 that engage the end of the piston spring 78 at one end and are engaged with the other end so as to be movable in the axial direction of the piston spring 78. Yes.

  The above-described divided body 103 has a shape shown in FIGS. 2 and 3, and has an annular flange portion 104 for locking one end of the corresponding one of the piston springs 65 and 78 on one end side. is doing. Further, the divided body 103 includes a pair of protrusions 105 having the same shape that protrude from the equally divided position in the circumferential direction of the flange portion 104, specifically, from the bisector position to the center axis side by a certain distance, and these protrusions 105 The extension part 106 of the same shape extended in one direction along the central axis from the front end edge part of the center axis side of this, and the same shape of the extension part 106 which protrudes on the opposite side to the center axis line And an outer claw portion 107. The continuous protruding portion 105, the extending portion 106, and the outer claw portion 107 constitute an inner arrangement portion 108. As a result, a pair of the inner arrangement portions 108 of the same shape are equally arranged in the circumferential direction of the flange portion 104. The distribution position is specifically formed at a bisection position.

  Here, the leading edge of each protrusion 105 has an arc shape with the same diameter centered on the central axis, and as a result, each extending portion 106 extending from each leading edge also has a central axis. It has a cylindrical surface with the same diameter as the center. Further, each outer claw portion 107 has an outer end surface 109 opposite to the central axis line having an arc shape with the same diameter and the same width centered on the central axis line, and is opposite to the flange portion 104 of the outer claw portion 107. On the outer diameter side, a tapered surface 110 having a smaller diameter as the distance from the flange portion 104 is increased.

  The divided body 103 is an evenly distributed position in the circumferential direction of the flange portion 104, specifically, a bisecting position, and a position (circumferential position) that is 90 degrees different from the above-described inner arrangement portion 108 and has a different diameter. Extending portions 116 having the same shape extending from the inner peripheral edge portion in the direction position along the central axis in the same direction as the inner arrangement portion 108, and having the same shape protruding from the distal end side of these extending portions 116 toward the central axis side Inner claw portion 117. The continuous extension portion 116 and the inner claw portion 117 constitute an outer arrangement portion 118, and as a result, a pair of the outer arrangement portions 118 of the same shape are equally distributed in the circumferential direction of the flange portion 104. Is formed at a position that is bisected and different from the inner arrangement portion 108.

  Here, each extending portion 116 extending from the inner peripheral edge portion of the flange portion 104 has a cylindrical surface shape having the same diameter and the same width with the central axis as the center. In addition, each inner claw portion 117 has an inner end surface 119 on the central axis side having an arc shape with the same diameter centering on the central axis, and the inner claw portion 117 has an inner diameter side opposite to the flange portion 104 on the inner diameter side. A tapered surface 120 having a larger diameter as the distance from the flange portion 104 increases.

  In the outer arrangement portion 118, the extension portion 116 extends directly from the inner peripheral edge portion of the flange portion 104, while the inner arrangement portion 108 has the extension portion 106 in the center from the inner peripheral edge portion of the flange portion 104. Since it extends from the tip edge portion of the protruding portion 105 protruding to the axial side, the inner arrangement portion 108 extends from the central axis (inner diameter) side than the outer arrangement portion 118 in the flange portion 104.

  Here, the outer diameter of the extension portion 106 of the inner arrangement portion 108 is smaller than the outer diameter of the extension portion 116 of the outer arrangement portion 118, and the inner claw portion 117 of the outer arrangement portion 118. The inner end surface 119 is substantially the same diameter as the outer diameter. Further, the inner diameter of the extending portion 116 of the outer arrangement portion 118 is substantially the same as the outer diameter of the outer end surface 109 of the outer claw portion 107 of the inner arrangement portion 108. In addition, the lengths in the axial direction of the extending portion 106 of the inner disposing portion 108 and the extending portion 116 of the outer disposing portion 118 are the same.

  The inner arrangement portion 108 and the outer arrangement portion 118 of the pair of split bodies 103 having the same shape are inserted into the piston spring 65 in the spring retainer 100 and the piston spring 78 in the spring retainer 101 from opposite directions. . Subsequently, as shown in FIG. 4A, the outer surface 118 of one divided body 103 and the inner surface 108 of the other divided body 103 are opposed to each other with the taper surfaces 120 and 110 facing each other. The inner surface portion 108 of the divided body 103 and the outer surface portion 118 of the other divided body 103 are opposed to each other with the taper surfaces 110 and 120 facing each other, and the divided body 103 is further pushed in the close proximity direction. Then, the tapered surfaces 110 and 120 come into contact with each other, and the extending portion 106 is elastically deformed to the central axis side while being displaced toward the central axis side by the force received by the outer claw portion 107 of each inner arrangement portion 108 at the tapered surface 110. At the same time, the extending portion 116 is elastically deformed to the opposite side to the central axis while being displaced to the opposite side to the central axis by the force received by the tapered surface 120 on the inner claw portion 117 of each outer arrangement portion 118. The outer claw portion 107 and the inner claw portion 117 get over each other in the central axis direction. Then, as shown in FIG. 4B, the outer claw portion 107 of each inner arrangement portion 108 returns to the side opposite to the central axis by the return of the extension portion 106, and the inner claw portion 117 of each outer arrangement portion 118. Is returned to the central axis side by the return of the extending portion 116.

  In this way, the pair of divided bodies 103 are engaged, and as shown in FIG. 1, the piston spring 65 is provided between the flange portions 104 in the spring retainer 100, and the piston spring 65 is provided between the flange portions 104 in the spring retainer 101. The spring 78 is interposed.

  The inner claw portion 117 constitutes a locking portion with respect to the outer claw portion 107 (claw portion), and the outer claw portion 107 constitutes a locking portion with respect to the inner claw portion 117 (claw portion). become.

  Here, as shown in FIG. 4 (b), the pair of divided bodies 103 has a surface 123 on the flange portion 104 side of the outer claw portion 107 of one divided body 103 and an inner claw portion 117 of the other divided body 103. The surface 124 on the flange portion 104 side of the inner claw portion 117 of one divided body 103 is in contact with the surface 124 on the flange portion 104 side of the other divided body 103, and the surface 123 on the flange portion 104 side of the outer claw portion 107 of the other divided body 103. The spring retainer 100 has a set length of the piston spring 65 (extension direction limit length), and the spring retainer 101 has a set length of the piston spring 78 (extension direction limit). Length) will be decided.

  Further, when the pair of divided bodies 103 are moved in the central axis direction so as to separate the surface 123 on the flange portion 104 side of the outer claw portion 107 from the surface 124 on the flange portion 104 side of the inner claw portion 117, The distance between the flange portions 104 is reduced in the axial direction, the piston spring 65 is contracted in the spring retainer 100, and the piston spring 78 is contracted in the spring retainer 101.

  Here, when the outer claw portion 107 moves away from the inner claw portion 117, the outer end surface 109 of the outer claw portion 107 is guided to the inner peripheral surface 126 of the extension portion 116 of the outer arrangement portion 118, and the inner claw The inner end surface 119 of the portion 117 is guided to the outer peripheral surface 127 of the extending portion 106 of the inner arrangement portion 108. In this way, the pair of divided bodies 103 slide relative to each other in the central axis direction. In addition, even if a pair of division body 103 tries to rotate relative to each other, the relative rotation is restricted and the disengagement between the division bodies 103 is restricted by the inner claw portions 117 and the outer claw portions 107 coming into contact with each other in the rotation direction. become.

  According to the present embodiment described above, the spring retainers 100 and 101 lock the ends of the piston springs 65 and 78 at one end and the other ends can move in the axial direction of the piston springs 65 and 78 with respect to each other. Since the pair of the same-shaped divided bodies 103 engaged with each other is provided, one type of divided body 103 may be manufactured and managed. Therefore, manufacturing cost and management cost can be reduced.

  Further, the inner claw portion 117 formed on the outer arrangement portion 118 of one divided body 103 is formed on the inner arrangement portion 108 provided on the center axis side of the outer arrangement portion 118 of the other divided body 103. The outer claw portion 107 is engaged, and the outer claw portion 107 formed on the inner arrangement portion 108 of the one divided body 103 is engaged with the inner claw portion 117 formed on the outer arrangement portion 118 of the other divided body 103. In the spring retainer 100, the end portion of the piston spring 65 is locked at one end side, and the other end sides are engaged with each other so as to be movable in the axial direction of the piston spring 65. In the retainer 101, the end of the piston spring 78 is locked at one end side, and the other end is engaged with each other so as to be movable in the axial direction of the piston spring 78. . Thus, since the pair of divided bodies 103 can have a simple structure, the manufacturing cost can be further reduced.

  In the above, a case where the outer arrangement portion 118 is provided at the bisecting position in the circumferential direction of the flange portion 104 of the divided body 103 and the inner arrangement portion 108 is provided at another bisecting position in between. As explained by way of example, if the outer arrangement portion 118 is provided at a plurality of equally divided positions in the circumferential direction of the flange portion 104 of the divided body 103 and the inner arrangement portion 108 is provided at another plurality of equally divided positions. good. For example, it is possible to provide the outer arrangement portion 118 at a three-divided position in the circumferential direction of the flange portion 104 of the divided body 103 and to provide the inner arrangement portion 108 at another three-divided position in between.

  Further, the inner claw portion 107 and the outer claw portion 117 protrude in the radial direction from the extending portions 106 and 116, respectively, but either one protrudes on the same surface as the extending portions 106 and 116. Also good.

  Further, one of the claw portions 107 and 117 is abolished, and a slit (locking portion) is formed in the extension portion on the side where the claw portion is abolished, so that the claw portion and the slit are engaged with each other. Anyway.

It is sectional drawing which shows the master cylinder of one Embodiment of this invention. It is a perspective view which shows the division body of the spring retainer used for the master cylinder of one Embodiment of this invention. FIG. 2 shows a split body of a spring retainer used in the master cylinder of one embodiment of the present invention, (a) is a cut end view passing through the outer arrangement portion, (b) is a view of (a) seen from the left side, (C) is the figure which looked at (a) from the right side, (d) is the cutting | disconnection end elevation which passes along an inner side arrangement | positioning part. The spring retainer used for the master cylinder of one embodiment of the present invention is shown, (a) is a cut end view before the division body is engaged, and (b) is a cut end view after the division body is engaged. .

Explanation of symbols

11 Master cylinder 15 Cylinder body 18 Primary piston (piston)
19 Secondary piston (piston)
63 Secondary pressure chamber (pressure chamber)
65 Secondary piston spring (piston spring)
76 Primary pressure chamber (pressure chamber)
78 Primary piston spring (piston spring)
100, 101 Spring retainer 103 Divided body 104 Flange part 107 Outer claw part (claw part, locking part)
108 Inner arrangement part (first arrangement part, second arrangement part)
117 Inner claw part (locking part, claw part)
118 Outside arrangement part (second arrangement part, first arrangement part)

Claims (3)

A cylinder body, a piston slidably provided on the cylinder body and forming a pressure chamber with the cylinder body, a piston spring disposed in the pressure chamber and biasing the piston, and expansion and contraction of the piston spring In a master cylinder having a spring retainer that locks both ends of the piston spring while allowing,
The spring retainer includes a pair of identically-shaped divided bodies whose one end side engages the end of the piston spring and whose other end side is engaged with each other so as to be movable in the axial direction of the piston spring. Master cylinder. The divided body is
A flange portion for locking an end portion of the piston spring;
A first disposition part formed with a claw part extending from the flange part and projecting in a direction different from the extending direction on the leading end side;
The claw portion is movably engaged in the axial direction by extending from a circumferential position different from the first arrangement portion extending from the flange portion and from a radial position different from the first arrangement portion. A second disposition portion formed with a locking portion to be stopped,
The pair of divided bodies engages the claw portions of one of the divided bodies with the locking portions of the other divided body, and the locking portions of the one divided body engage with the locking portions of the other divided body. The master cylinder according to claim 1, wherein the claw portion is engaged. The divided body is
A flange portion for locking an end portion of the piston spring;
An outer arrangement portion formed with an inner claw portion extending from the flange portion and projecting toward the central axis on the tip side;
An inner arrangement in which an outer claw portion is formed at a position different from the outer arrangement portion of the flange portion and extending from the central axis side than the outer arrangement portion and projecting on the tip end side opposite to the central axis line. And has a section,
Engage the inner claw portion of one divided body with the outer claw portion of the other divided body, and engage the outer claw portion of the one divided body with the inner claw portion of the other divided body. The master cylinder according to claim 1, wherein:

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