JP2017144905A - Fluid-pressure master cylinder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fluid-pressure master cylinder in which a return spring is provided between a retainer which is contacted with a piston and a stopper which is contacted with a wall part that faces a liquid chamber, formed in a cylinder body, from the opposite side of the piston, and a guide pin for regulating the maximum interval between the retainer and the stopper is arranged between the retainer and the stopper, which can reduce man-hours for assembling the guide pin to the stopper to reduce costs.SOLUTION: A long hole 38 extending long along one diameter line of a guide pin 36 is formed in a stopper 35, and an engagement part 39 which can switch between a state where the part can be inserted through the long hole 38 and a state where the part can be engaged with a surface facing a wall part 11a of the stopper 35, in response to turning of the guide pin 36 relative to the stopper 35 is provided at an end part, near the stopper 35, of the guide pin 36 restricted from moving relative to the retainer 34 in a direction along a shaft line of a cylinder hole 12.SELECTED DRAWING: Figure 1

Description

  The present invention enables a cylinder body having a cylinder hole, a piston slidably fitted in the cylinder hole, and a volume to be changed according to sliding of the piston in the cylinder hole. A wall facing the hydraulic chamber formed in the cylinder body from the opposite side of the piston; a retainer that contacts the piston in the hydraulic chamber; and a wall that contacts the wall in the hydraulic chamber. A hydraulic pressure master, a retainer and a return spring provided between the stopper, and a guide pin disposed between the retainer and the stopper so as to regulate a maximum distance between the retainer and the stopper. Regarding cylinders.

  A retainer is brought into contact with a piston that is slidably fitted into a cylinder hole of the cylinder body, and a stopper is brought into contact with a wall portion facing from a side opposite to the piston to a hydraulic chamber formed in the cylinder body. A hydraulic master cylinder in which a return spring is provided between the retainers and the maximum distance between the retainer and the stopper is regulated by a guide pin is already known from Patent Document 1, for example.

Japanese Patent No. 4658916

  In the one disclosed in Patent Document 1, the end portion on the stopper side of the guide pin is caulked and coupled to the stopper in order to receive the load applied to the stopper by the return spring, and the assembly man-hour is increased by caulking, It was a factor of cost increase.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a hydraulic master cylinder capable of reducing the man-hours for assembling the guide pin to the stopper and reducing the cost.

  In order to achieve the above object, the present invention provides a cylinder body having a cylinder hole, a piston slidably fitted in the cylinder hole, and a volume corresponding to the sliding of the piston in the cylinder hole. A wall that faces the hydraulic chamber formed in the cylinder body from the opposite side to the piston, a retainer that contacts the piston in the hydraulic chamber, and the hydraulic chamber The stopper is in contact with the wall portion, the return spring provided between the retainer and the stopper, and the retainer and the stopper are disposed between the retainer and the stopper so as to restrict the maximum distance between the retainer and the stopper. In the hydraulic master cylinder including the guide pin, the stopper is formed with a long hole extending along a diameter line of the guide pin. The guide pin, which is restricted in relative movement with the retainer in the direction along the axis of the hole, is connected to the stopper-side end so that it can be inserted into the long hole and the surface of the stopper facing the wall. A first feature is that an engaging portion is provided that is capable of switching a state that can be matched according to the rotation of the guide pin with respect to the stopper.

  According to the present invention, in addition to the configuration of the first feature, a rotation restricting means for restricting rotation of the guide pin with respect to the stopper in a state where the engaging portion is engaged with the stopper. A second feature is that it is provided between the engaging portions.

  In addition to the configuration of the first or second feature, the present invention is configured such that the rotation restricting means engages a restricting protrusion provided on one of the stopper and the engaging portion, and the restricting protrusion. The third feature is that it is composed of a restriction hole or a restriction recess provided in the other of the stopper and the engaging portion.

  According to the first feature of the present invention, the engaging portion provided on the guide pin can be inserted through a long hole formed in the stopper so as to extend long along one diameter line of the guide pin, and the stopper The guide pin can be assembled to the stopper with a simple operation that eliminates the caulking process. The cost can be reduced by reducing the number of assembling steps. In addition, since the caulking process is not required, the guide pin can be made of any material, regardless of metal or resin, and the choice of materials can be expanded.

  According to the second feature of the present invention, since the rotation of the guide pin with respect to the stopper is restricted by the rotation restricting means with the engaging portion engaged with the stopper, the engagement state of the guide pin with respect to the stopper Can be reliably maintained.

  Furthermore, according to the third feature of the present invention, the rotation restricting means is composed of one restricting projection of the stopper and the engaging portion and the other restricting hole or restricting recess of the stopper and the engaging portion. The rotation restricting means can be configured with a simple structure.

It is a longitudinal cross-sectional view of the tandem hydraulic master cylinder of the first embodiment. FIG. 2 is an enlarged view of a portion indicated by an arrow 2 in FIG. 1. FIG. 3 is a view taken in the direction of arrow 3 in FIG. 2. FIG. 4 is a sectional view taken along line 4-4 of FIG. It is a figure corresponding to FIG. 3 of 2nd Embodiment.

  Hereinafter, an embodiment of the present invention will be described with reference to FIG. 1 to FIG. 4. First, in FIG. 1, the hydraulic master cylinder is a tandem master cylinder for a hydraulic brake of a vehicle. The cylinder body 11 of this hydraulic master cylinder has a bottomed cylinder hole 12 with a wall 11a integrally formed in the cylinder body 11 as a closed end. In the cylinder hole 12, a first hydraulic pressure chamber 13 is formed between the wall portion 11 a and the first hydraulic pressure chamber 13. A second hydraulic pressure chamber 14 is formed between the first piston 15. A first return spring 17 that urges the first piston 15 toward the side away from the wall portion 11 a is slidably fitted to the second piston 16. The second hydraulic pressure chamber 14 accommodates a second return spring 18 that urges the second piston 16 to move away from the first piston 15. The second piston 16 is connected to a push rod 19 that operates in response to an operation of a brake pedal (not shown). The cylinder body 11 has a first output port 21 that communicates with the first hydraulic pressure chamber 13. And a second output port 22 communicating with the second hydraulic pressure chamber 14 is provided.

  The first piston 15 is provided integrally with a first cylindrical portion 15a and an axially intermediate portion of the first cylindrical portion 15a, and a first partition wall portion 15b that divides the inside of the first cylindrical portion 15a in the front-rear direction. The second piston 16 is provided integrally with the second cylindrical portion 16a and the axially intermediate portion of the second cylindrical portion 16a so that the inside of the second cylindrical portion 16a is moved back and forth. It forms so that it may have the 2nd division wall part 16b to divide.

  First and second boss portions 23, 24 are integrally projected on the upper portion of the cylinder body 11, and a reservoir 27 is inserted into the boss portions 23, 24 via grommet seals 25, 26. Mounted. The first boss portion 23 is provided with a first communication hole 28 that communicates with the reservoir 27 so that the inner end thereof opens to the inner peripheral surface of the cylinder hole 12. A second communication hole 29 communicating with the reservoir 27 is provided so that an inner end thereof is opened on the inner peripheral surface of the cylinder hole 12. A pair of cup seals 30 and 31 sandwiching the first communication hole 28 between each other are elastically formed on the inner peripheral surface of the cylinder hole 12 on the outer periphery of the first cylindrical portion 15 a of the first piston 15. A pair of cup seals 32 and 33 that are mounted so as to contact each other and sandwich the second communication hole 29 therebetween elastically contact the outer periphery of the second cylindrical portion 16a of the second piston 16. It is attached in this way.

  In the first hydraulic chamber 13, the first retainer 34 is brought into contact with the first partition wall portion 15 b of the first piston 15, and the cylinder body 11 is in contact with the first hydraulic chamber 13. A first stopper 35 is in contact with the wall portion 11a, and the first return spring 17 is provided between the first retainer 34 and the first stopper 35, and the first retainer 34 and the first stopper 35 are provided. A first guide pin 36 that restricts the maximum distance therebetween is disposed between the first retainer 34 and the first stopper 35.

  The first retainer 34 has a bottomed cylindrical portion formed such that one end portion on the first stopper 35 side is closed by the end wall 34a and becomes slightly larger in diameter as it approaches the first partition wall portion 15b. 34b and a flange portion 34c projecting radially outward from the other end portion of the bottomed cylindrical portion 34b so as to be in contact with the first partition wall portion 15b. The first stopper 35 includes a dish-shaped part 35a that opens toward the wall 11a side of the cylinder body 11, and a radial direction from the opening end of the dish-shaped part 35a so as to contact the wall 11a. The first return spring 17 is formed so as to integrally have a flange portion 35b projecting outward. The first return spring 17 includes the flange portion 34c of the first retainer 34 and the flange portion 35b of the first stopper 35. Between.

  The first guide pin 36 is provided with an enlarged diameter portion 37 disposed at an end portion on the first retainer 34 side. The enlarged diameter portion 37 is accommodated in the bottomed cylindrical portion 34b so as to be movable between the end wall 34a of the bottomed cylindrical portion 34b and the first partition wall portion 15b. The first guide pin 36 is restricted from moving relative to the first retainer 34 in the direction along the axis of the cylinder hole 12 within a range defined by the end wall portion 34a and the first partition wall portion 15b. The

  Referring to FIGS. 2 and 3 together, a long hole 38 that extends long along one diameter line of the first guide pin 36 is formed in the dish-shaped portion 35 a of the first stopper 35. Further, the end of the first guide pin 36 on the first stopper 35 side can be inserted into the long hole 38 as shown by a chain line in FIG. 3, and as shown by a solid line in FIGS. A state where the surface of the first stopper 35 facing the wall portion 11a, that is, the surface of the dish-shaped portion 35a that can be engaged with the surface facing the wall portion 11a is set to the rotation of the first guide pin 36 relative to the first stopper 35. An engaging portion 39 that can be switched according to the movement is provided, and this engaging portion 39 is formed in a cross shape with the first guide pin 36 so as to be along the one diameter line of the first guide pin 36. And provided integrally with the first guide pin 36.

  By the way, the engaging portion 39 of the first guide pin 36 is inserted through the first retainer 34 so as to penetrate the end wall portion 34a of the first retainer 34, as shown in FIG. In addition, an elongated insertion hole 40 extending along one diameter line of the first guide pin 36 is provided in the first retainer 34 so as to penetrate the engaging portion 39 and disable the insertion of the enlarged diameter portion 37. The end wall 34a is formed.

  In FIG. 1 again, the second retainer 41 is brought into contact with the second partition wall portion 16 b of the second piston 16 in the second hydraulic pressure chamber 14, and the second hydraulic pressure chamber 14 A second stopper 42 is brought into contact with the first partition wall 15b of the first piston 15, and the second return spring 18 is provided between the second retainer 41 and the second stopper 42, The second guide pin 43 that restricts the maximum distance between the second retainer 41 and the second stopper 42 is disposed between the second retainer 41 and the second stopper 42. 43 is the same structure as the relative movement restricting structure of the first guide pin 36 relative to the first retainer 34 in the direction along the axis of the cylinder hole 12, and the second in the direction along the axis of the cylinder hole 12. Relative movement with respect to the retainer 41 With the braking, it is engaged with the second stopper 42 in the same structure as the engagement structure of the first guide pin 36 to the first stopper 35. That is, an enlarged diameter portion 37 is provided at an end portion of the second guide pin 43 on the second retainer 41 side, and an engaging portion 39 is provided at an end portion of the second guide pin 43 on the second stopper 42 side. The second retainer 41 is formed with a long hole-like insertion hole 40 extending along one diameter line of the second guide pin 43, and the second stopper 42 has one of the second guide pins 43. A long hole 38 extending long along the diameter line is formed.

  Next, the operation of this embodiment will be described. The first and second stoppers 35 and 42 are formed with elongated holes 38 extending long along one diameter line of the first and second guide pins 36 and 43. The first and second guide pins 36 and 43 of the first and second guide pins 36 and 43 whose relative movement with the first and second retainers 34 and 41 in the direction along the axis of the cylinder hole 12 of the cylinder body 11 is restricted. 2 at the end on the side of the stoppers 35 and 42, a state in which the elongated hole 38 can be inserted, the surface of the first stopper 35 facing the wall 11a of the cylinder body 11, and the first piston 15 has. The state in which the second stopper 42 can be engaged with the surface of the partition wall 15b is determined according to the rotation of the first and second guide pins 36, 43 relative to the first and second stoppers 35, 42. Switch Since the effective engaging portion 39 is provided, the first and second guide pins 36 and 43 can be assembled to the first and second stoppers 35 and 42 by a simple operation that does not require a caulking process. Man-hours can be reduced and costs can be reduced. In addition, since the caulking process is not required, the first and second guide pins 36 and 43 can be manufactured using any material, regardless of metal or resin, and the choice of materials can be expanded.

  FIG. 5 shows a second embodiment of the present invention. The parts corresponding to those of the first embodiment are indicated by the same reference numerals, and detailed description thereof is omitted.

  Between the first stopper 35 and the engaging portion 39 of the first guide pin 36, the first guide for the first stopper 35 in a state where the engaging portion 39 is engaged with the first stopper 35. A rotation restricting means 45 for restricting the rotation of the pin 36 is provided.

  The rotation restricting means 45 includes a restricting projection 46 provided on one of the first stopper 35 and the engaging portion 39, and the first stopper 35 and the engaging portion so as to engage the restricting projection 46. In this embodiment, a pair of restricting projections 46 projecting from the dish-like portion 35a of the first stopper 35, The rotation restricting means 45 is constituted by a pair of restricting recesses 47 provided in the engaging portion 39 so that the restricting protrusions 46 are engaged.

  Also, a rotation restricting means similar to the above-described rotation restricting means 45 is provided between the second guide pin 43 and the second stopper 42.

  According to the second embodiment, rotation of the first guide pin 36 relative to the first stopper 35 is performed by the rotation restricting means 45 in a state where the engaging portion 39 is engaged with the first stopper 35. Since the rotation of the second guide pin 43 that is regulated and similarly engaged with the second stopper 42 with respect to the second stopper 42 is regulated, the first and second guide pins 36 and 42 The engaged state with respect to the first and second stoppers 35 and 42 can be reliably maintained.

  Moreover, the rotation restricting means 45 engages the restricting protrusion 46 provided on one of the first stopper 35 and the engaging portion 39 (the first stopper 35 in this embodiment) with the restricting protrusion 46. Thus, the rotation restricting means 45 can be simplified by the restriction hole or the restriction recess 47 provided in the other one of the first stopper 35 and the engaging portion 39 (the engaging portion 39 in this embodiment). Can be configured with a structure.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various design changes can be made without departing from the present invention described in the claims. Is possible.

  For example, in the above-described embodiment, the case where the present invention is applied to a tandem hydraulic master cylinder has been described. However, the present invention may be applied to a hydraulic master cylinder in which one piston is slidably fitted into a cylinder hole. Is possible.

DESCRIPTION OF SYMBOLS 11 ... Cylinder body 11a ... Wall part 12 ... Cylinder hole 13, 14 ... Hydraulic pressure chamber 15, 16 ... Piston 15b ... Partition wall part 17, 18, which is a wall part Return springs 34, 41 ... Retainers 35, 42 ... Stoppers 36, 43 ... Guide pins 38 ... Long holes 39 ... Engaging portions 45 ... Rotation restricting means 46 ... Restriction protrusion 47 ... recessed recess

Claims (3)

  A cylinder body (11) having a cylinder hole (12), pistons (15, 16) slidably fitted in the cylinder hole (12), and the piston (15 in the cylinder hole (12)) 16), the volume can be changed according to the sliding of the cylinder body (11), and the hydraulic chamber (13, 14) formed in the cylinder body (11) faces from the opposite side to the piston (15, 16). A wall (11a, 15b), a retainer (34, 41) in contact with the piston (15, 16) in the hydraulic chamber (13, 14), and an interior of the hydraulic chamber (13, 14) A stopper (35, 42) abutted on the wall (11a, 15b), a return spring (17, 18) provided between the retainer (34, 41) and the stopper (35, 42), The retainer (34, 41) and A hydraulic pressure comprising a retainer (34, 41) and a guide pin (36, 43) disposed between the stopper (35, 42) so as to regulate the maximum distance between the stoppers (35, 42). In the master cylinder, a long hole (38) extending long along one diameter line of the guide pin (36, 43) is formed in the stopper (35, 42), and the direction along the axis of the cylinder hole (12) is formed. The guide pin (36, 43) restricted in relative movement with the retainer (34, 41) at the end of the stopper (35, 42) side can be inserted into the elongated hole (38). In addition, the state in which the stopper (35, 42) can engage with the surface facing the wall (11a, 15b) is switched according to the rotation of the guide pin (36, 43) with respect to the stopper (35, 42). Hydraulic pressure master cylinder, characterized in that the ability engagement portion (39) is provided.   A rotation restricting means (45) for restricting the rotation of the guide pins (36, 43) relative to the stopper (35, 42) in a state where the engaging portion (39) is engaged with the stopper (35, 42). 2 is provided between the stopper (35, 42) and the engaging portion (39).   The rotation restricting means (45) engages the restricting protrusion (46) provided on one of the stopper (35, 42) and the engaging portion (39) with the restricting protrusion (46). 3. The hydraulic master cylinder according to claim 2, comprising a restriction hole or a restriction recess provided in the other of the stopper (35, 42) and the engagement part (39).

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