JP6396745B2 - 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)).

  As shown in FIG. 4, the solenoid pump 200 of Patent Document 1 includes a pump housing (fixed core) 201, a movable core 202 provided to be movable with respect to the pump housing 201, and the movable core 202 as an electromagnetic wave. An electromagnetic coil 203 that is moved to the fixed core side by force, a suction valve 205 and a discharge valve 206 that control the inflow and outflow of hydraulic fluid to and from a pressure chamber 204 formed in the pump housing 201, and a piston that increases and decreases the volume of the pressure chamber 204 207.

  In the solenoid pump 200, the O-ring 208 is held in the step portion 211 formed in the through hole 209 using the ring member 212. With this O-ring 208 as a boundary, one end side is a region where the brake fluid exists (pressure chamber 204), and the other end side is a region communicating with the atmosphere.

  In the technique of Patent Document 1, in addition to the step portion 211 that holds the O-ring 208, a step portion 213 that holds (contacts) the ring member 212 is also formed. Since the plurality of step portions 211 and 213 are formed, the diameter of the through-hole 209 on the movable core 202 side is increased, so that the thickness of the peripheral wall of the pump housing (fixed core) 201 is reduced. The cross-sectional area is small. When the electromagnetic coil 203 is excited, the peripheral wall of the pump housing 201 forms an electromagnetic circuit as indicated by an arrow. However, when the thickness of the peripheral wall of the pump housing 201 is reduced, the magnetic loss increases. As a countermeasure against this, if it is attempted to secure the thickness of the peripheral wall of the pump housing (fixed core) 201, the pump housing 201 becomes large, resulting in an increase in the size of the solenoid pump 200.

JP 2013-53632 A

  An object of the present invention is to reduce the size of a solenoid pump while sealing between a pump housing and a piston and reducing magnetic loss.

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 biases the piston toward the movable core, the pump housing includes a through hole through which the piston is inserted and the fixed core. a first member made, the suction valve and the discharge valve is composed of a second member provided, one end side of the side where the second member is disposed The side where the movable core is arranged and the other end, the inner peripheral portion of the first member, together with the return spring is arranged, said and one end side of the coil, wherein the first member and the second A seal member that seals between the second member and the piston is disposed in a space formed between the member, and the pressure chamber includes the suction valve, the discharge valve, the piston, and the seal member. , is formed by the through hole is partitioned, characterized Rukoto disposed on one end side.

  The invention according to claim 2 is characterized in that the second member is formed of a non-magnetic material.

  The invention according to claim 3 is characterized in that one end of the first member is press-fitted into the inner periphery of the second member.

  The invention according to claim 4 is characterized in that a flange portion is formed in the middle of the piston, and one end of the return spring is received by this flange portion.

  In the invention according to claim 5, the intake valve includes a valve seat portion formed on the second member, a valve body seated on the valve seat portion, and a valve spring that biases the valve body in the seating direction. The suction valve is configured to be coaxial with the piston and receives one end of the valve spring at the tip of the piston.

  The invention according to claim 6 is characterized in that a discharge valve is arranged on the outer peripheral side of the suction valve.

In the invention according to claim 1, the pump housing includes a first member that includes a through-hole through which the piston is inserted and serves as a fixed core, and a second member that is provided with the suction valve and the discharge valve. A return spring is disposed on the inner periphery of the. Since a seal member that seals between the second member and the piston is disposed in a space formed at one end side of the coil and between the first member and the second member, a separate member that holds the seal member is provided. This part is unnecessary. For this reason, since only the return spring has to be disposed on the inner peripheral portion of the first member, the through hole of the first member can be made as small as possible. As a result, while maintaining the outer diameter of the peripheral wall, the thickness of the peripheral wall of the first member serving as the fixed core can be ensured thick, and the magnetic loss can be reduced without increasing the outer diameter of the pump housing. . That is, it is possible to reduce the size of the solenoid pump while sealing between the pump housing and the piston and reducing magnetic loss.

  In the invention which concerns on Claim 2, since the 2nd member is formed with the nonmagnetic material, an inexpensive material can be employ | adopted and cost reduction of components can be achieved.

  In the invention which concerns on Claim 3, since the one end side of the 1st member is press-fit in the inner periphery of the 2nd member, even if it does not use a fastening member, a 1st member and a 2nd member can be easily fitted can do.

  In the invention which concerns on Claim 4, since the flange part is formed in the middle of a piston, it can receive a return spring with a simple shape.

  In the invention according to claim 5, the intake valve includes a valve seat portion formed on the second member, a valve body seated on the valve seat portion, and a valve spring that biases the valve body in the seating direction. Composed. The suction valve is arranged coaxially with the piston and receives one end of the valve spring at the tip of the piston, so that a part for receiving the valve spring becomes unnecessary and the number of parts can be reduced. .

  In the invention which concerns on Claim 6, since the discharge valve is arrange | positioned at the outer peripheral side of the suction valve, the dimension of the axial direction of a pump housing can be shortened, and size reduction of a solenoid pump can be achieved.

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 disassembled perspective view of the solenoid pump shown in FIG. It is sectional drawing of the solenoid pump which concerns on a prior art.

  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 second member 47 that is the insertion portion 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 and 3, the solenoid pump 40 includes a cylindrical pump housing 41, at least a part of which is a fixed core 46, and a bottomed cylindrical shape fixed to the other end of the pump housing 41. A guide pipe 42 and a piston 51 inserted through a through hole 45 penetrating the pump housing 41 are provided.

  The pump housing 41 includes a through-hole 45 through which the piston 51 is inserted and is formed separately from the first member 46 serving as the fixed core 46, and the first member 46, and the suction valve 70 and the discharge valve 80 are provided. The second member 47 is provided.

  A pressure chamber 60 is formed in the pump housing 41. The solenoid pump 40 is arranged so as to be able to advance and retreat in the guide pipe 42, presses the piston 51 toward the pressure chamber 60, a coil 44 sheathed on the pump housing 41 and the guide pipe 42, and pressurizes the hydraulic fluid. A suction valve 70 that opens when sucking into the chamber 60 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 first member (fixed core) 46 on the other end side of the pump housing 41 is made of a magnetic material that is an iron-based material and has a cylindrical shape. A second member (insertion portion) 47 on one end side of the pump housing 41 is inserted in a liquid-tight manner through a sealing material 92 into a mounting hole 91 formed in a base body 90 serving as a base. A guide pipe 42 is attached to the outer periphery of the first member 46. 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 first member 46 includes a first flange portion 46a formed on the outer periphery of the end portion on one end side, and a convex portion 46b formed on the end portion on the one end side.

  Further, in the first member 46, the through hole 45 includes a large-diameter portion 45a formed on the other end side, a small-diameter portion 45b formed on one end side and having a smaller diameter than the large-diameter portion 45a, and a large-diameter portion 45a. And a step portion 45c formed between the small diameter portion 45b. A return spring 64 that urges the piston 51 toward the movable core 43, a piston 51 that is movable in the axial direction, and a cylinder that guides the piston 51 are formed in the large-diameter portion 45 a that forms the inner peripheral portion of the first member 46. A guide member 65 is arranged.

  The second member 47 includes a second flange portion 47a formed on the outer periphery of the end portion on the other end side, and a concave portion 47b formed on the inner periphery on the other end side and into which the convex portion 46b is press-fitted. Since one end side of the first member 46 is press-fitted into the inner periphery of the second member 47, the first member 46 and the second member 47 can be easily fitted without using a fastening member. . The second member 47 is formed of a nonmagnetic material. For this reason, inexpensive materials, such as resin, can be employ | adopted and cost reduction of components can be achieved.

  Further, in the second member 47, the through hole 45 is provided with a seal arrangement hole 45d in which the seal member 56 is arranged from the other end side, a pressure chamber 60, a suction communication hole 45e for guiding hydraulic fluid, and a filter 61. A filter arrangement hole 45f, and a support step 45g formed between the seal arrangement hole 45d and the pressure chamber 60.

  The second member 47 and the seal disposing hole 45d which is a space formed between the first member 46 and the second member 47 at a position deviating from the inner diameter direction of the coil 44 (one end side from the coil 44). A seal member 56 that seals between the piston 51 is disposed. The seal member 56 is, for example, an O-ring.

  The convex portion 46b of the first member 46 is press-fitted into the concave portion 47b of the second member 47, and the first flange portion 46a overlaps the second flange portion 47a. The first flange portion 46 a is fixed to the opening of the attachment hole 91 by a ring-shaped retaining member 93. As a result, the first member 46 and the second member 47 are both fixed to the mounting hole 91. In the embodiment, the pump housing 41 composed of the first member 46 and the second member 47 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 is press-fitted or caulked. It can be fixed.

  On one end side of the second member 47, a filter arrangement hole 45 f is opened toward the suction fluid pressure path 38 formed at the bottom of the mounting hole 91 of the base body 90. A suction valve 70 is provided at the center of the second member 47, and a filter 61 is provided at one end of the suction valve 70.

  In addition, a communication hole 62 is formed in the outer peripheral portion of the second member 47 to communicate the discharge hydraulic pressure path 39 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.

  The pressure chamber 60 is disposed on one end side. The pressure chamber 60 is formed by partitioning the through-hole 45 with a suction valve 70, a discharge valve 80, and a piston 51 (O-ring 56).

  The piston 51 includes a main body 52 that is movably inserted into the through hole 45, a flange 53 that is formed in the middle of the main body 52 and receives one end of the return spring 64, and a valve formed at the tip of the main body 52. And a spring seat 54 for receiving one end of the spring 73. Since only the flange portion 53 is formed in the middle of the piston 51, the return spring 64 can be received with a simple shape.

  The diameter of the flange 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 flange portion 53. The communication groove 55 makes it possible to freely move the air between the one end side and the other end side of the flange portion 53 and to smoothly move the piston 51 in the axial direction.

  A return spring 64 that urges the piston 51 toward the movable core 43 is disposed in the large-diameter portion 45 a of the first member 46. The return spring 64 is a coil spring, one end of which is received by the flange portion 53 and the other end is received by the step portion 45c.

  The piston 51 is inserted into the through hole 45 of the pump housing 41 through the seal member 56 so as to be slidable in the axial direction, and is configured such that one end portion thereof protrudes and retracts from 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. Note that the piston 51 does not have an opening serving as a passage for the hydraulic fluid in a portion facing the pressure chamber 60, and the hydraulic fluid does not flow through the piston 51.

  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 suction valve 70 includes a valve seat portion 71 formed on the second member 47, a spherical valve body 72 seated on the valve seat portion 71, and a valve spring 73 that biases the valve body 72 in the seating direction. It consists of and.

  The valve body 72 is biased by a valve spring 73 so as to be seated on the valve seat portion 71. 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.

  The suction valve 70 is arranged coaxially with the piston 51 and receives one end of the valve spring 73 at the tip end (spring seat 54) of the piston 51, so that a part for receiving the valve spring 73 is not necessary. The number of parts can be reduced.

  The return spring 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.

  Further, since the discharge valve 80 is disposed on the outer peripheral side 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 is reduced to reduce the size of the solenoid pump 40. be able to.

  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 portion 81 formed in the communication hole 62 of the second member 47, a spherical discharge-side valve body 82 seated on the discharge-side valve seat portion 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. The discharge side retainer 83 is press-fitted into the communication hole 62. 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 urged by the discharge side valve spring 84 so as to be seated on the discharge side valve seat portion 81. 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 in 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 to the other end side of the first member (fixed core) 46 of the pump housing 41 from the outside, and is fixed to the first member 46 by welding, for example. The fixing method is not limited to welding, and may be press-fitting or caulking.

  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. 2, when the coil 44 is excited, a magnetic circuit is formed as shown by an arrow, and the movable core 43 is drawn toward one end side. Pressed by the movable core 43, the piston 51 moves to the pressure chamber 60 side. As the volume of the pressure chamber 60 is reduced, the pressure chamber 60 is increased in pressure, the discharge side valve element 82 is moved outward, and the discharge valve 80 is opened. The hydraulic fluid in the pressure chamber 60 flows to the discharge valve 80 and further flows out from the discharge liquid passage 85 to the discharge liquid pressure path 39.

  Subsequently, when the coil 44 is demagnetized, the piston 51 and the movable core 43 are moved to the other end side 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 moves to the pressure chamber 60 side, and the discharge valve 80 closes. When the pressure chamber 60 is further depressurized, the valve body 72 moves to the pressure chamber 60 side, and the suction valve 70 is opened. The working fluid flows from the suction fluid pressure path 38 to the suction valve 70 and is further sucked into the pressure chamber 60. Subsequently, the valve body 72 moves to one end side, and the suction valve 70 is closed. By repeating such an operation, the working fluid is continuously sucked and discharged.

  In the solenoid pump 40, the seal member 56 is disposed using a seal disposition hole 45 d that is a space formed between the first member 46 and the second member 47 at a position deviated from the inner diameter direction of the coil 44. Therefore, a separate part for holding the seal member 56 is not required. For this reason, since only the return spring 64 has to be disposed on the inner peripheral portion of the first member 46, the through hole 45 of the first member 46 can be made as small as possible. As a result, the thickness of the peripheral wall of the first member 46 serving as the fixed core can be ensured thick while maintaining the outer diameter of the peripheral wall of the first member 46. Even if the outer diameter of the pump housing 41 is not increased, the sectional area on the magnetic circuit can be increased and the magnetic loss can be reduced. That is, it is possible to reduce the size of the solenoid pump 41 while sealing between the pump housing 41 and the piston 51 and reducing magnetic loss.

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.

Further, the seal member 56 is not limited to the O-ring, and may have other shapes.
In the embodiment, one end of the valve spring 73 is received by the tip of the piston 51. However, a retainer that receives one end of the valve spring 73 may be provided.
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.

  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 ... Pump housing, 43 ... Movable core, 44 ... Coil, 45 ... Through-hole, 45d ... Seal arrangement | positioning hole (between the 1st member 46 and the 2nd member 47) 46 ... first member (fixed core), 47 ... second member (insertion portion), 51 ... piston, 53 ... flange portion, 56 ... sealing member (O-ring), 60 ... pressure chamber, 64 ... Return spring, 70... Suction valve, 71... Valve seat, 72.

Claims (6)

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;
In a solenoid pump including a return spring that biases the piston toward the movable core,
The pump housing includes a first member that has a through-hole through which the piston is inserted and serves as the fixed core, and a second member that is provided with the suction valve and the discharge valve, and the second member is disposed. The side where the movable core is disposed is the one end side, and the side where the movable core is disposed is the other end side,
The return spring is disposed on the inner periphery of the first member,
A seal member that seals between the second member and the piston is disposed in one end side of the coil and in a space formed between the first member and the second member ,
Said pressure chamber, said at the seal member and the piston and the suction valve and the discharge valve, wherein the through hole is formed in the can separated, solenoid pumps, wherein Rukoto disposed on one end side.
The solenoid pump according to claim 1, wherein
The solenoid pump according to claim 1, wherein the second member is made of a non-magnetic material. The solenoid pump according to claim 1 or 2,
A solenoid pump, wherein one end of the first member is press-fitted into an inner periphery of the second member. The solenoid pump according to any one of claims 1 to 3,
A solenoid pump characterized in that a flange portion is formed in the middle of the piston, and one end of the return spring is received by the flange portion. The solenoid pump according to any one of claims 1 to 4,
The suction valve includes a valve seat portion formed on the second member, a valve body seated on the valve seat portion, and a valve spring that biases the valve body in a seating direction.
The solenoid pump, wherein the suction valve is arranged coaxially with the piston and receives one end of the valve spring at a tip portion of the piston. The solenoid pump according to any one of claims 1 to 5,
A solenoid pump, wherein the discharge valve is disposed on an outer peripheral side of the suction valve.

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