JP6389722B2 - Solenoid pump - Google Patents

Description

  The present invention relates to a solenoid pump including a piston that slides in response to movement of a movable core within a pump housing.

  For example, some automobiles, motorcycles, and the like include a hydraulic brake, and a brake hydraulic pressure control device that optimizes the braking of the hydraulic brake is put into practical use. The brake fluid pressure control device has a pump that increases the hydraulic fluid of the brake. As such a pump, a solenoid pump is known in which a piston in a pump housing is slid by a solenoid to increase or decrease the volume of a pressure chamber (see, for example, Patent Document 1 (FIG. 2)).

  The solenoid pump disclosed in Patent Document 1 includes a pump housing as a fixed core, a movable core provided to be movable with respect to the pump housing, a coil for moving the movable core toward the fixed core by electromagnetic force, and a pump. A suction valve and a discharge valve that control the inflow and outflow of the hydraulic fluid to and from the pressure chamber formed in the housing, and a piston that increases and decreases the volume of the pressure chamber.

  The suction valve includes a valve seat member provided in the pump housing and having a suction port; a suction valve body formed in a spherical shape and seated on the valve seat member; and a suction valve provided on the valve seat member and formed in a cup shape A retainer that houses the spring, and a suction valve spring that is provided in the retainer and biases the suction valve body toward the valve seat member.

  However, since the retainer is attached to the valve seat member by press-fitting, the valve seat member and the retainer are required to have high dimensional accuracy. For this reason, the processing cost and assembly cost of the suction valve are increased, and the cost of parts is increased.

JP 2013-53632 A

  It is an object of the present invention to provide a solenoid pump that does not require high dimensional accuracy in a valve seat member and a retainer, eliminates a press-fitting process at the time of assembling the retainer, and can reduce component costs.

In the invention according to claim 1, a fixed core, a movable core provided so as to be movable with respect to the fixed core, a coil for moving the movable core toward the fixed core, a cylindrical pump housing, A pressure chamber formed in the pump housing, a suction valve and a discharge valve for controlling the inflow and outflow of the hydraulic fluid to the pressure chamber, and slides in accordance with the movement of the movable core in the pump housing, and the pressure In a solenoid pump including a piston that increases or decreases the volume of the chamber and a return spring that is disposed in the pressure chamber and biases the piston toward the movable core, the suction valve is disposed coaxially with the piston. , A valve seat member fitted into the pump housing, a valve body seated on the valve seat member, a cup-shaped retainer, and the retainer and the valve body Is composed of a valve spring disposed in the back opposite piston side of the spring is in contact with the retainer, the retainer by the biasing force of the return spring is retained, the piston includes a body portion, the body A spring contact portion that is provided on one end side of the portion and contacts the other end side of the return spring, and a spring seat that is provided on the spring contact portion and supports the return spring. It has a communication groove that is larger than the diameter of the main body and communicates with one end side and the other end side of the spring contact portion on the outer peripheral portion of the spring contact portion .

  In the invention according to claim 2, the retainer includes a flange portion against which the return spring abuts, and the flange portion is urged by the return spring to abut against the valve seat member.

  In the invention according to claim 3, the side surface of the retainer is formed with a liquid passage hole communicating with the inside and the outside, and the pump housing is formed with a communication hole orthogonal to the piston shaft, and at least of the liquid passage hole and the communication hole. It is arranged so that a part may overlap.

  The invention according to claim 4 is characterized in that a discharge valve is arranged on the outer periphery of the suction valve.

  In the invention which concerns on Claim 5, the inner peripheral part of the pump housing is formed in the step shape which diameter-expands sequentially toward a reverse side from a movable core, It is characterized by the above-mentioned.

In the invention according to claim 1, the suction valve is arranged coaxially with the piston, and a valve seat member fitted in the pump housing, a valve body seated on the valve seat member, a cup-shaped retainer, The retainer and a valve spring disposed between the valve bodies are configured. Since the non-piston side of the return spring is in contact with the retainer and the retainer is held by the urging force of the return spring, it is not necessary to press-fit the retainer into the valve seat member. As a result, high dimensional accuracy in the valve seat member and the retainer is not necessary, and the press-in process at the time of assembling the retainer is eliminated, so that the part cost can be reduced.
In addition, the piston has a main body portion and a spring contact portion having a diameter larger than that of the main body portion. The spring contact portion is formed with a communication groove communicating with one end side and the other end side on the outer peripheral portion. ing. With this communication groove, it is possible to freely move the hydraulic fluid between the one end side and the other end side of the spring contact portion, and to smoothly move the piston in the axial direction.

  In the invention which concerns on Claim 2, a retainer is provided with the flange part which a return spring contacts. Since the flange portion is biased by the return spring and is in contact with the valve seat member, the retainer can be held with a simple configuration, and the cost of parts can be reduced.

  In the invention which concerns on Claim 3, the liquid passage hole which connects inside and outside is formed in the side surface of a retainer, and the communicating hole orthogonal to a piston shaft is formed in a pump housing. Since the liquid passage hole and the communication hole are arranged so that at least a part thereof overlaps in the direction of the communication hole, the working fluid that has come out of the retainer's fluid passage hole flows linearly into the communication hole, and the working fluid flows smoothly. It can be distributed.

  In the invention according to claim 4, since the discharge valve is arranged on the outer periphery of the suction valve, it is not necessary to provide the discharge valve in the axial direction of the piston, and the size of the axial direction is reduced to reduce the size of the solenoid pump. be able to.

  In the invention according to claim 5, since the inner peripheral portion of the pump housing is formed in a stepped shape that gradually increases in diameter from the movable core toward the opposite side, all of the stepped shape portions of the pump housing are formed from one direction. Can be processed. For this reason, compared with the case where it processes from the axial direction both sides of a pump housing, a process man-hour can be shortened and the manufacturing cost of a pump housing can be reduced.

FIG. 3 is a hydraulic circuit diagram of a brake hydraulic pressure control device employing a solenoid pump according to the present invention. It is sectional drawing of the solenoid pump which concerns on this invention. It is a principal part enlarged view of the solenoid pump shown in FIG. It is a disassembled perspective view of the solenoid pump shown in FIG. It is an effect | action figure of the solenoid pump which concerns on this invention.

  Embodiments of the present invention will be described below with reference to the accompanying drawings. The drawings are viewed in the direction of the reference numerals.

First, a hydraulic fluid circuit of a brake hydraulic pressure control device 10 for a bar handle vehicle to which a solenoid pump according to an embodiment of the present invention is applied will be described.
As shown in FIG. 1, the brake hydraulic pressure control device 10 is suitably employed in a bar handle type vehicle such as a motorcycle equipped with a hydraulic brake and an all-terrain vehicle (ATV). The solenoid pump according to the embodiment of the present invention can also be applied to a brake fluid pressure control device for a four-wheeled vehicle. Hereinafter, the brake fluid pressure control device 10 for the front wheels of the motorcycle will be described. The brake hydraulic pressure control device 10 includes a brake system 20 for the front wheels, and can control the braking force applied to the wheel brakes 11 provided on the front wheels by the control device 12, thereby enabling antilock brake control of the wheel brakes 11. To do.

  The brake fluid pressure control device 10 includes a brake operator 14 provided on the bar handle 13, a master cylinder 15 that is activated by the operation of the brake operator 14, and a reservoir 16 that stores hydraulic fluid to be sent to the master cylinder 15. The brake system 20 transmits the hydraulic pressure from the master cylinder 15 to the wheel brake 11, and the control device 12 controls the braking force applied to the wheel brake 11.

  The brake system 20 brakes the wheel brake 11 by operating the brake operator 14. The brake system 20 has a main flow path from the inlet port 21 to the outlet port 22 that leads to the master cylinder 15, and a subport that leads directly from the main flow path to the reservoir 16. 23 sub-flow paths are provided. The master cylinder 15 and the inlet port 21 are connected by a first pipe 24, the outlet port 22 and the wheel brake 11 are connected by a second pipe 25, and the sub-port 23 and the reservoir 16 are connected by a third pipe. 26.

  The master cylinder 15 has a cylinder to which a reservoir 16 for storing hydraulic fluid (brake fluid) is connected, and the hydraulic fluid is slid in the cylinder axial direction by the operation of the brake operator 14 in the cylinder. An outflowing piston is provided.

  The brake system 20 includes an inlet valve 31, an outlet valve 32, and a solenoid pump 40. The inlet valve 31 and the outlet valve 32 are electromagnetic valves, the opening / closing of which is controlled by the control device 12, and the operation / stop of the solenoid pump 40 is also controlled by the control device 12.

  A flow path (oil path) from the inlet port 21 to the inlet valve 31 is an output hydraulic pressure path 33, and a flow path from the inlet valve 31 to the outlet port 22 is a wheel hydraulic pressure path 34. A flow path from the first branch portion 34a of the wheel hydraulic pressure path 34 to the outlet valve 32 is a branch path 35, and a flow path from the outlet valve 32 to the second branch section 36a in the middle of the subport 23 is an open path 36. A flow path from the second branch part 36 a to the subport 23 is referred to as a shared path 37. A flow path from the second branch part 36 a to the solenoid pump 40 is referred to as a suction hydraulic pressure path 38, and a flow path from the solenoid pump 40 to the first branch part 34 a is referred to as a discharge hydraulic pressure path 39.

  The brake fluid pressure control device 10 has a function of switching between a normal state, a pressure-reducing state during ABS control (anti-lock brake control), a holding state during ABS control, or a pressure-increasing state during ABS control. In the normal state, the output hydraulic pressure path 33 and the wheel hydraulic pressure path 34 are communicated (the inlet valve 31 is opened), and the branch path 35 and the open path 36 are blocked (the outlet valve 32 is closed). State. In the depressurized state during the ABS control, the output hydraulic pressure path 33 and the wheel hydraulic pressure path 34 are blocked (the inlet valve 31 is closed), and the branch path 35 and the open path 36 are communicated (the outlet valve 32 is opened). ). In the holding state during ABS control or the pressure increasing state during ABS control, the output hydraulic pressure path 33 and the wheel hydraulic pressure path 34 and the branch path 35 and the open path 36 are blocked (inlet valve 31 and outlet valve 36, respectively). The valve 32 is closed).

  The inlet valve 31 is a normally open type electromagnetic valve provided between the output hydraulic pressure passage 33 and the wheel hydraulic pressure passage 34. The inlet valve 31 is open in a normal state, thereby allowing the hydraulic fluid pressure from the master cylinder 15 to be transmitted from the output hydraulic pressure passage 33 to the wheel brake 11 via the wheel hydraulic pressure passage 34. . Further, the inlet valve 31 is closed by a signal from the control device 12 when the front wheel is about to be locked, and the hydraulic fluid pressure from the master cylinder 15 is transferred from the output hydraulic pressure passage 33 via the wheel hydraulic pressure passage 34 to the wheel brake 11. It is blocked from being transmitted to.

  The outlet valve 32 is a normally closed electromagnetic valve provided between the wheel hydraulic pressure path 34 and the open path 36 via the branch path 35. The outlet valve 32 is closed in a normal state. The outlet valve 32 is released by a signal from the control device 12 when the front wheel is about to be locked, and releases the hydraulic fluid pressure acting on the wheel brake 11 from the wheel hydraulic pressure passage 34 to the release passage 36 via the branch passage 35. Furthermore, the hydraulic fluid released to the open path 36 temporarily flows into the reservoir 16 through the dual-purpose path 37. In this way, the pressure is reduced during ABS control.

  The solenoid pump 40 is provided between the suction fluid pressure passage 38 and the discharge fluid pressure passage 39, and is operated by the movable core 43, the coil 44 (see FIG. 2), etc. The hydraulic fluid stored in the reservoir 16 is sucked through the passage 38 and discharged to the discharge hydraulic pressure passage 39. For this reason, the hydraulic fluid pressure can be increased with respect to the wheel brake 11. The solenoid pump 40 operates in a pressure-increasing state during ABS control by a signal from the control device 12. When the solenoid pump 40 is in operation (in a pressure-increasing state), the control device 12 closes the inlet valve 31 and the outlet valve 32, and between the output hydraulic pressure path 33 and the wheel hydraulic pressure path 34, the branch path 35, The connection with the open passage 36 is blocked, and the hydraulic fluid from the discharge hydraulic pressure passage 39 flows into the wheel hydraulic pressure passage 34.

  The reservoir 16 sends to the tank for storing the working fluid for the master cylinder 15, the tank for releasing the working fluid from the wheel fluid pressure passage 34 in the pressure-reduced state during ABS control, and the solenoid pump in the pressure-increasing state during ABS control. It also serves as a tank for storing hydraulic fluid.

  The dual-purpose path 37 is a flow path for sending hydraulic fluid from the wheel hydraulic pressure path 34 in a reduced pressure state during ABS control to the reservoir 16, and a flow path for sending hydraulic fluid from the reservoir 16 in a pressure increase state during ABS control to the solenoid pump. Doubles as The control device 12 controls each device of the brake fluid pressure control device 12 based on measurement values from a front wheel speed sensor (not shown).

  In the embodiment, the hydraulic circuit described above is used. However, the present invention is not limited to this, and a reservoir for the master cylinder, a reservoir for releasing the hydraulic fluid from the wheel hydraulic pressure passage 34 and sending the hydraulic fluid to the solenoid pump 40, May be a separate hydraulic circuit, and other forms may be used as long as the hydraulic circuit incorporates the solenoid pump 40.

Next, normal brake control by the brake fluid pressure control device 10 will be described.
In normal brake control, the brake system 20 is in a state where the flow path from the master cylinder 15 to the wheel brake 11 is communicated via the output hydraulic pressure path 33, the inlet valve 31, and the wheel hydraulic pressure path 34. When the brake operation element 14 is operated, the working hydraulic pressure acts on the wheel brake 11 via the output hydraulic pressure path 33, the inlet valve 31, and the wheel hydraulic pressure path 34, and the front wheels can be braked. When the brake operator 14 is returned, the hydraulic fluid that has acted on the wheel brake 11 is returned to the master cylinder 15 via the wheel hydraulic pressure passage 34, the inlet valve 31, and the output hydraulic pressure passage 33.

Next, ABS control by the brake fluid pressure control device 10 will be described.
The ABS control is executed when the front wheels are likely to be locked, and controls the inlet valve 31, the outlet valve 32 and the solenoid pump 40 to reduce, increase and maintain the hydraulic fluid pressure acting on the wheel brake 11. Is executed. Based on the measured value from a wheel speed sensor (not shown) for the front wheels, the controller 12 controls the pressure reduction, pressure increase and holding.

  In the reduced pressure state, the inlet valve 31 is closed to shut off the output hydraulic pressure path 33 and the wheel hydraulic pressure path 34, and the outlet valve 32 is opened to open the gap between the wheel hydraulic pressure path 34 and the release path 36. Then, the solenoid pump 40 is stopped. The hydraulic fluid in the wheel hydraulic pressure passage 34 communicating with the wheel brake 11 flows into the reservoir 16 through the branch passage 35, the release passage 36, and the dual-use passage 37, and the hydraulic fluid pressure acting on the wheel brake 11 is reduced. .

  In the holding state, when the inlet valve 31 is closed, the output hydraulic pressure path 33 and the wheel hydraulic pressure path 34 are blocked, and when the outlet valve 32 is closed, the wheel hydraulic pressure path 34 (branch path 35) and the open path 36 are closed. And the solenoid pump 40 is stopped. The hydraulic fluid is confined in the flow path closed by the wheel brake 11, the inlet valve 31, the outlet valve 32, and the solenoid pump 40, and the hydraulic fluid acting on the wheel brake 11 is kept constant.

  In the pressure increasing state, the inlet valve 31 is closed to shut off the output hydraulic pressure path 33 and the wheel hydraulic pressure path 34, and the outlet valve 32 is closed to close the gap between the wheel hydraulic pressure path 34 and the open path 36. The solenoid pump 40 is activated by being shut off. By the operation of the solenoid pump 40, the working fluid is sucked from the reservoir 16 through the dual-purpose passage 37 and the suction fluid pressure passage 38, and enters the flow path closed by the wheel brake 11, the inlet valve 31, the outlet valve 32, and the solenoid pump 40. Then, the hydraulic fluid is sent from the discharge hydraulic pressure passage 39, the pressure in the flow passage is increased, and the wheel brake 11 is operated.

Next, the solenoid pump 40 will be described. For convenience, the side where the insertion portion 41A of the pump housing 41 of the solenoid pump 40 is disposed is referred to as “one end side”, and the side where the movable core 43 is disposed is referred to as “the other end side”.
As shown in FIGS. 2 to 4, the solenoid pump 40 includes a cylindrical pump housing 41, at least a part of which is a fixed core, and a bottomed cylindrical guide fixed to the other end side of the pump housing 41. A pipe 42 and a piston 51 inserted through a through hole 45 penetrating the pump housing 41 are provided.

  A pressure chamber 60 is formed in the pump housing 41. The solenoid pump 40 is disposed in the guide pipe 42 so as to be able to advance and retreat, and a movable core 43 that presses the piston toward the pressure chamber 60; a coil 44 that is externally mounted on the pump housing 41 and the guide pipe 42; 60, a suction valve 70 that opens when suctioning, and a discharge valve 80 that opens when hydraulic fluid is discharged from the pressure chamber 60 are provided. The coil 44 is an electromagnetic coil.

  The pump housing 41 has a cylindrical shape made of a magnetic material that is an iron-based material, and includes an insertion portion 41A on one end side and a body portion 41B on the other end side. The insertion portion 41A is liquid-tightly inserted into a mounting hole 91 formed in the base body 90 serving as a base via a sealing material 92. A guide pipe 42 is attached to the outer periphery of the trunk portion 41B. A through hole 45 through which the piston 51 is inserted is formed in the pump housing 41 along the axis of the pump housing 41. The insertion portion 41 </ b> A is fixed to the opening of the attachment hole 91 by a ring-shaped retaining member 93. In the embodiment, the pump housing 41 is fixed to the mounting hole 91 by the retaining member 93. However, the present invention is not limited to this, and the pump housing 41 may be fixed by press fitting or caulking.

  An inner peripheral portion of the pump housing 41 is formed in a stepped shape that gradually increases in diameter from the movable core 43 toward the opposite side, and sequentially from the movable core 43 side, the through hole 45, the seal holding hole 46, and the suction valve holding. A hole 47 and a suction port 48 are formed. A pressure chamber 60 is formed using a part of the seal holding hole 46 and a part of the suction valve holding hole 47.

  By forming the inner peripheral portion of the pump housing 41 into a stepped shape that sequentially increases in diameter from the movable core 43 toward the opposite side, the stepped shape portion of the pump housing 41 can be processed entirely from one direction. For this reason, compared with the case where it processes from the axial direction both sides of the pump housing 41, a process man-hour can be shortened and the manufacturing cost of the pump housing 41 can be reduced.

  On one end side of the insertion portion 41A, a suction port 48 opens toward a suction fluid pressure path 38 (see FIG. 1) formed in the bottom of the mounting hole 91 of the base body 90. A suction valve 70 is provided on one end side of the suction valve holding hole 47, and a filter 61 is provided on one end side of the suction valve 70.

  In addition, a communication hole 62 is formed in the outer peripheral portion of the insertion portion 41 </ b> A to connect the discharge hydraulic pressure path 39 (see FIG. 1) formed on the side wall of the mounting hole 91 of the base body 90 and the pressure chamber 60. A discharge valve 80 is provided inside the opening of the communication hole 62. A communication port 63 of the discharge valve 80 is provided on the side wall of the pump housing 41 facing the pressure chamber 60.

  The pressure chamber 60 is disposed on one end side. The pressure chamber 60 is formed by partitioning the seal holding hole 46 and the suction valve holding hole 47 by the suction valve 70, the discharge valve 80 and the piston 51 (O-ring 56).

  The piston 51 includes a main body 52 that is movably inserted into the through hole 45, a spring abutting portion 53 that is provided on one end of the main body 52 and abuts on the other end of the return spring 64, and the spring abutting portion. 53 and a spring seat 54 that supports the return spring 64. The diameter of the spring contact portion 53 is larger than the diameter of the main body portion 52, and a communication groove 55 that connects the one end side and the other end side is formed in the outer peripheral portion of the spring contact portion 53. The communication groove 55 makes it possible to freely move the hydraulic fluid between the one end side and the other end side of the spring contact portion 53, and to smoothly move the piston 51 in the axial direction.

A return spring 64 that biases the piston 51 toward the movable core 43 is disposed in the pressure chamber 60. The return spring 64 is a coil spring.
The seal holding hole 46 is provided with an O-ring 56 that seals the piston 51 and the inner peripheral portion of the pump housing 41. The O-ring 56 is held in the seal holding hole 46 by a ring member 57 press-fitted into the seal holding hole 46.

  The piston 51 is inserted through the through-hole 45 of the pump housing 41 through the O-ring 56 so as to be slidable in the axial direction, and is configured such that one end thereof protrudes and retracts with respect to the pressure chamber 60 by sliding. Yes. That is, the volume of the pressure chamber 60 is reduced when the piston 51 slides to one end side and one end portion of the piston 51 projects into the pressure chamber 60, and the piston 51 slides to the other end side. The volume increases as one end of the sunk from the pressure chamber 60.

  The suction valve 70 is a one-way valve that opens and closes the flow path between the suction fluid pressure path 38 and the pressure chamber 60, and is arranged coaxially with the axis of the piston 51. The intake valve 70 includes a valve seat member 71 fitted in the pump housing 41, a spherical valve body 72 seated on the valve seat member 71, a cup-shaped retainer 73, the retainer 73 and the valve body 72. And a valve spring 74 disposed therebetween.

  The valve body 72 is biased by a valve spring 74 so as to be seated on the valve seat 71c. As the piston 51 moves in the direction of increasing the volume of the pressure chamber 60 (the direction toward the other end side), the valve body 72 is opened by the pressure chamber 60 being depressurized, and the pressure from the suction fluid pressure path 38 is increased. The working fluid flows into the chamber 60. Further, the valve body 72 is closed by increasing the pressure of the pressure chamber 60 as the piston 51 moves in the direction of reducing the volume of the pressure chamber 60 (the direction toward the one end side). From flowing out to the suction fluid pressure passage 38.

  Note that the force that the return spring 64 biases the retainer 73 is greater than the force that the valve spring 74 biases the valve body 72. For this reason, even if the valve body 72 is separated from the valve seat member 71, the retainer 73 maintains contact with the valve seat member 71. The return pin 64 has a biasing force that biases the piston 51 to the non-actuated position when it is not actuated. For this reason, when the coil 44 described later is demagnetized, the piston 51 slides in the direction away from the pressure chamber 60 (the movable core 43 side) by the return force of the return spring 64.

  The retainer 73 includes a flange portion 75 against which one end side of the return spring 64 abuts. The flange portion 75 is urged by the return spring 64 and abuts against the valve seat member 71. The return spring 64 has an anti-piston 51 side (one end side) in contact with the flange portion 75 of the retainer 73, and a piston 51 side (other end side) in contact with the spring contact portion 53 of the piston 51. The retainer 73 is held by the urging force.

  The valve seat member 71 includes a large-diameter portion 71a fitted into the intake valve holding hole 47, a small-diameter portion 71b formed with a smaller diameter than the large-diameter portion 71a and fitted with the retainer 73, and an end of the small-diameter portion 71b. It has a valve seat 71c formed in a tapered shape at which the valve body 72 is seated, and a suction through-hole 71d formed inside and through which hydraulic fluid passes. The axial direction of the retainer 73 can be supported by the large diameter portion 71a, and the radial direction of the retainer 73 can be supported by the small diameter portion 71b.

  As described above, since the retainer 73 is held by the urging force of the return spring 64, it is not necessary to press-fit the retainer 73 into the valve seat member 71 during assembly. As a result, high dimensional accuracy in the valve seat member 71 and the retainer 73 is not required, and a press-fitting process at the time of assembling the retainer 73 is eliminated, so that the part cost can be reduced. Further, since the flange portion 75 is urged by the return spring 64 and is in contact with the valve seat member 71, the retainer 73 can be held with a simple configuration, and the cost of parts can be reduced. Furthermore, the retainer 73 itself formed in a cup shape can also serve as the spring seat of the return spring 64.

  On the side surface of the retainer 73, a plurality of liquid passage holes 76 communicating between the inside and the outside are formed. The communication hole 62 and the communication port 63 of the pump housing 41 are disposed orthogonal to the piston shaft. As viewed from the communication hole 62 side, at least one of the at least one liquid communication hole 76 and the communication hole 62 is disposed so as to overlap. For this reason, in the direction of the communication hole, the liquid passage hole 76 and the communication hole 62 are arranged so that at least a part thereof overlaps, so that the hydraulic fluid that has come out of the liquid passage hole 76 of the retainer 73 linearly communicates with the communication hole 62. The working fluid can be circulated smoothly.

  Further, since the discharge valve 80 is disposed on the outer periphery of the suction valve 70, it is not necessary to provide the discharge valve 80 in the axial direction of the piston 51, and the size of the axial direction can be reduced to reduce the size of the solenoid pump 40. Can do.

  The discharge valve 80 is a one-way valve that opens and closes the flow path between the pressure chamber 60 and the discharge hydraulic pressure path 39, and is provided in the inner space of the opening of the communication hole 62. The discharge valve 80 includes a discharge-side valve seat member 81 fitted in the communication hole 62 of the pump housing 41, a spherical discharge-side valve body 82 seated on the discharge-side valve seat member 81, and a cup-shaped discharge side. The retainer 83 and a discharge side valve spring 84 disposed between the discharge side retainer 83 and the discharge side valve body 82 are configured. The discharge side retainer 83 is formed with a discharge liquid passage hole 85 communicating between the inside and the outside, and the opening end of the discharge side retainer 83 is crimped to the discharge side valve seat member 81. The discharge valve 80 is arranged so that the opening / closing direction of the discharge-side valve element 82 is perpendicular to the axial direction of the piston 51.

  The discharge side valve element 82 is biased by the discharge side valve spring 84 so as to be seated on the discharge side valve seat 81a. As the piston 51 moves in the direction of reducing the volume of the pressure chamber 60 (the direction toward the one end side), the pressure chamber 60 is increased in pressure and opened, and the hydraulic fluid passes from the pressure chamber 60 to the discharge hydraulic pressure passage 39. Leaks. Further, the discharge side valve element 82 is closed as the pressure chamber 60 is depressurized as the piston 51 moves in the direction in which the volume of the pressure chamber 60 increases (the direction toward the other end). The hydraulic fluid is prevented from flowing into the pressure chamber 60 from the hydraulic pressure path 39.

  The movable core 43 is made of a magnetic material, and moves in the axial direction inside the guide pipe 42 in a state where one end face thereof is in contact with the other end of the piston 51. The movable core 43 is attracted to the pump housing 41 by exciting the coil 44 and moves to one end side against the urging force of the return spring 64. When the movable core 43 moves to one end side, the piston 51 is also pushed to one end side, and one end portion of the piston 51 protrudes into the pressure chamber 60. As a result, the volume of the pressure chamber is reduced and the pressure chamber is increased.

  A communication groove 43 a is formed on the outer peripheral portion of the movable core 43 along the axial direction of the movable core 43. One end side of the communication groove 43a communicates with a space between one end surface of the movable core 43 and the other end surface of the pump housing 41, and the other end side of the communication groove 43a is connected to the other end surface of the movable core 43 and the guide pipe. It communicates with the space between the inside.

  The guide pipe 42 has a bottomed cylindrical shape, is fitted from the outside to the other end of the body 41B of the pump housing 41, and is fixed to the body 41B by welding, for example. The fixing method is not limited to welding, and may be press-fitting or caulking. An outside air introduction hole 42 a for introducing the atmosphere is formed at the bottom of the guide pipe 42. Air is introduced into the space between the other end surface of the movable core 43 and the inner surface of the guide pipe 42 through the outside air introduction hole 42 a, and further, the one end surface of the movable core 43 and the pump housing 41 are communicated through the communication groove 43 a of the movable core 43. Atmosphere is introduced into the space between the other end surface of the slab. For this reason, air freely enters and leaves the space between the one end surface of the movable core 43 and the other end surface of the pump housing 41, and smooth sliding of the movable core 43 and the piston 51 in the axial direction can be ensured.

  The coil 44 is mounted with a resin bobbin 44a, and a yoke 44b that forms a magnetic path is provided outside the bobbin 44a.

Next, the operation of the solenoid pump 40 described above will be described.
As shown in FIG. 5A, when the coil 44 (see FIG. 2) is excited, the movable core 43 is drawn toward one end, and the piston 51 indicated by the imaginary line is positioned at the position of the piston 51 indicated by the solid line. Moving. As the volume of the pressure chamber 60 is reduced, the pressure chamber 60 is increased in pressure, the discharge side valve element 82 indicated by the imaginary line moves to the position of the discharge side valve element 82 indicated by the solid line, and the discharge valve 80 opens. The hydraulic fluid in the pressure chamber 60 flows from the communication port 63 to the discharge valve 80 as indicated by an arrow (1), and further flows out from the discharge liquid passage 85 to the discharge hydraulic pressure path 39 as indicated by an arrow (2).

  Subsequently, when the coil 44 is demagnetized, the piston 51 and the movable core 43 move to the other end side as indicated by an arrow (3) by the biasing force of the return spring 64. As the volume of the pressure chamber 60 increases, the pressure chamber 60 is depressurized, the discharge side valve element 82 indicated by the solid line moves as indicated by the arrow (4), and the discharge valve 80 is closed. When the pressure chamber 60 is further depressurized, the valve body 72 moves as indicated by the arrow (5), and the suction valve 70 is opened.

  Then, as shown in FIG. 5B, the working fluid flows from the suction fluid pressure path 38 to the suction valve 70 as indicated by an arrow (6), and further sucked into the pressure chamber 60 as indicated by an arrow (7). . Subsequently, the valve body 72 moves as indicated by an arrow (8), and the intake valve 70 is closed. By repeating such an operation, the working fluid is continuously sucked and discharged.

In the embodiment, the hydraulic circuit is a circuit sharing the reservoir 16 for the master cylinder 15, the outlet valve 32, and the solenoid pump 40. However, the invention is not limited to this, and the reservoir for the master cylinder, A circuit in which the reservoir 16 for the outlet valve 32 and the solenoid pump 40 is separated may be used, and if the solenoid pump 40 is incorporated, another hydraulic circuit may be used.
Further, the present invention is not limited to the above-described embodiment, and the volume of the pressure chamber 60, the diameter of the piston 51, and the discharge amount of the piston 51 may be changed as appropriate, and the discharge amount of the hydraulic fluid may be different. There is no problem.

In the embodiment, the return spring 64 is received by the flange portion 75 of the retainer 73. However, the present invention is not limited to this, and the return spring 64 may be received by the end face on the other end side of the retainer 73. In this case, the flange portion 75 may not be provided.
The liquid passage hole 76 and the communication hole 62 may not partially overlap each other.
Further, the discharge valve 80 may be arranged not in the outer periphery of the suction valve 70 but in an axial direction with respect to the suction valve 70.
Further, the inner peripheral portion of the pump housing 41 may not be sequentially enlarged from the movable core 43 side toward the opposite side.

  The solenoid pump of the present invention is suitable for a vehicle brake fluid pressure control device.

DESCRIPTION OF SYMBOLS 10 ... Brake hydraulic pressure control apparatus, 40 ... Solenoid pump, 41 ... Fixed core (pump housing), 43 ... Movable core, 44 ... Coil, 51 ... Piston, 52 ... Main-body part, 53 ... Spring contact part, 54 ... Spring Seat, 55 ... Communication groove, 60 ... Pressure chamber, 62 ... Communication hole, 64 ... Return spring, 70 ... Suction valve, 71 ... Valve seat member, 72 ... Valve body, 73 ... Retainer, 74 ... Valve spring, 75 ... Flange Part, 76 ... liquid passage hole, 80 ... discharge valve.

Claims (5)

A fixed core;
A movable core provided movably with respect to the fixed core;
A coil for moving the movable core toward the fixed core;
A cylindrical pump housing;
A pressure chamber formed in the pump housing;
A suction valve and a discharge valve for controlling the inflow and outflow of the hydraulic fluid to the pressure chamber;
A piston that slides in accordance with the movement of the movable core in the pump housing and increases or decreases the volume of the pressure chamber;
A solenoid pump including a return spring disposed in the pressure chamber and biasing the piston toward the movable core;
The intake valve is disposed coaxially with the piston;
It comprises a valve seat member fitted in the pump housing, a valve body seated on the valve seat member, a cup-shaped retainer, and a valve spring disposed between the retainer and the valve body. ,
The non-piston side of the return spring is in contact with the retainer, and the retainer is held by the biasing force of the return spring ,
The piston includes a main body portion, a spring abutting portion provided on one end side of the main body portion and abutting on the other end side of the return spring, and a spring seat provided on the spring abutting portion and supporting the return spring. Have
The spring contact portion is larger than the diameter of the main body portion, and has a communication groove that communicates one end side and the other end side of the spring contact portion on the outer peripheral portion of the spring contact portion. A featured solenoid pump.
The solenoid pump according to claim 1, wherein
The retainer includes a flange portion with which the return spring abuts,
The solenoid pump, wherein the flange portion is urged by the return spring and is in contact with the valve seat member. The solenoid pump according to claim 1 or 2,
The side surface of the retainer is formed with a liquid passage hole that communicates inside and outside,
The pump housing is formed with a communication hole orthogonal to the piston shaft,
A solenoid pump, wherein the liquid passage hole and the communication hole are arranged so that at least a part thereof overlaps. The solenoid pump according to any one of claims 1 to 3,
A solenoid pump, wherein the discharge valve is disposed on an outer periphery of the suction valve. The solenoid pump according to any one of claims 1 to 4,
The solenoid pump according to claim 1, wherein an inner peripheral portion of the pump housing is formed in a stepped shape that gradually increases in diameter from the movable core toward the opposite side.

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