JP5071227B2 - Pump device - Google Patents

Description

  The present invention relates to a pump device mounted on a vehicle brake control device, and more particularly to a pump device having a drain flow path for discharging brake fluid leaked from a pump chamber to the outside without entering the motor.

  In general, a vehicle brake control device is provided with a pump device that returns brake fluid in a wheel cylinder individually corresponding to each wheel to the master cylinder side. In this pump device, an output shaft of a motor is connected to a pump piston in a motor cam chamber (accommodating chamber) so that power can be transmitted. The pump device increases or decreases the volume of the pump chamber formed on the side opposite to the motor cam chamber as viewed from the pump piston in the process of reciprocating the pump piston in accordance with the rotation of the motor, thereby pumping from the wheel cylinder side. The suction of the brake fluid into the chamber and the discharge of the brake fluid from the pump chamber to the master cylinder side are executed alternately.

  Here, in the pump device, when the pump is driven, the brake fluid in the pump chamber leaks to the motor cam chamber via the clearance between the outer peripheral surface of the pump piston and the inner peripheral surface of the cylinder, and the leaked brake fluid is output to the motor output shaft. There was a risk of entering into the motor. Therefore, it is desirable to discharge the brake fluid leaking into the motor cam chamber to the outside without allowing the brake fluid to enter the motor.

Therefore, conventionally, as shown in Patent Document 1, for example, a drain channel that connects the motor cam chamber and the outside of the apparatus is formed at a position that is the lowest in the direction of gravity in the peripheral wall portion of the pump case, and through this drain passage A technique has been proposed in which brake fluid flows down from the motor cam chamber to the outside of the device by gravity and is discharged. In the pump device described in Patent Document 1, the porous sintered member is disposed in the opening on the lower end side of the drain channel. The sintered member allows the brake fluid in the motor cam chamber to gradually flow out through the fine holes of the sintered member, and fluid other than the brake fluid such as water enters the motor cam chamber via the drain channel. The entry is restricted.
Japanese Patent Laid-Open No. 10-273039

  By the way, for example, when traveling on a rough road where the vehicle body is submerged, the air in the motor cam chamber is suddenly cooled by the submergence due to heat dissipation due to the rotation driving of the motor, and the motor cam chamber In some cases, negative pressure may be generated as the volume of the internal air contracts. In this case, the pump device described in Patent Document 1 has a problem that water flowing into the drain flow path enters the motor cam chamber through the fine holes of the sintered member as the negative pressure is generated.

  The present invention has been made in view of such circumstances, and an object of the present invention is to discharge brake fluid from the storage chamber to the outside of the device with a simple configuration, and from the outside of the device to the storage chamber. An object of the present invention is to provide a pump device that can suppress the ingress of fluid.

  In order to achieve the above object, the pump device of the present invention includes a pump chamber that sucks and discharges brake fluid based on the pump drive of the movable member (17, 37, 40), and the movable member (17, 40). A housing chamber (14) for housing the output shaft (13a) of the motor (13) separated from the pump chamber and coupled to the movable member (17, 40) so as to be capable of transmitting power; 14) A pump device (11) having a drain flow path (18) communicating with the outside from the storage chamber (14) to the outside in the middle of the drain flow path (18). A restricting means (20) for permitting liquid discharge and restricting the entry of fluid from the outside into the storage chamber (14) is provided, and the restricting means (20) is disposed in the drain flow path (18). The formed valve seat (21) Is also urged upward in the gravitational direction based on the fluid pressure acting through the drain flow path (18), and thus the drain flow path (18) with respect to the valve seat (21). ) And a valve body (24) that is in contact with the valve body (24) so as to be closed, and is in sliding contact with the inner surface of the drain passage (18) along the drain passage (18). The valve body (24) can be guided, and at least a sliding contact portion with the drain flow path (18) includes a sliding member (23) made of a material capable of absorbing the brake fluid. .

  According to the above configuration, when brake fluid leaks from the pump chamber side to the storage chamber, the brake fluid is absorbed by the sliding member in the process of flowing down in the drain flow path. Then, the brake fluid absorbed by the sliding member gradually drains according to gravity from the sliding member, and is discharged to the outside of the pump device. On the other hand, when fluid other than brake fluid, such as a small amount of water, enters the drain channel from the outside of the device due to factors such as being exposed to splashing water, the entered fluid is trapped by the sliding member. Fluid does not enter the storage chamber through the drain channel. In addition, when a large amount of fluid enters the drain flow path from the outside of the device due to, for example, traveling on a rough road where the vehicle is submerged, the valve body biased by the fluid pressure of the fluid that has entered. Contacts the valve seat and closes the drain passage. That is, in such a case, the restricting means can exert a waterproof effect adapted to a more severe external environment by the valve body appropriately closing the drain flow path based on the fluid pressure acting from the outside. Further, the sliding member absorbs the brake fluid, so that it is easy to maintain the lubrication state between the sliding member and the inner surface of the drain channel. Furthermore, the sliding member can exhibit a sealing function effectively by becoming liquid-tight due to the absorption of the brake fluid, and the valve body and the sliding member are integrally formed. Therefore, unlike the case where these members have a separate configuration, it is possible to reduce the number of parts and improve the ease of assembly to the apparatus. Therefore, with a simple configuration, it is possible to discharge the brake fluid leaked from the pump chamber to the storage chamber to the outside of the device and to prevent the fluid from entering the storage chamber from the outside of the device.

  Further, in the pump device of the present invention, the regulating means (20) is configured such that the sliding member (23) is located in the housing chamber (14) more than the valve body (24) in the middle of the drain flow path (18). It is provided so that it may be located on the opposite side.

  According to the said structure, the valve body is arrange | positioned at the storage chamber side used as the back | inner side of a drain flow path rather than a sliding member. Therefore, when the sliding member traps foreign matter such as dust that has entered the drain flow path, it is possible to restrict the foreign matter from reaching the valve body and the valve seat. Therefore, it can suppress that the sealing function of a valve body falls with a foreign material adhering to a valve body or a valve seat.

  Further, in the pump device of the present invention, the regulating means (20) is configured such that the sliding member (23) is located in the housing chamber (14) more than the valve body (24) in the middle of the drain flow path (18). It is provided so that it may be located in the side.

  According to the said structure, the sliding member is arrange | positioned at the storage chamber side used as the back | inner side of a drain flow path rather than a valve body. Therefore, the fluid can be restricted from reaching the storage chamber by trapping the fluid that attempts to enter the storage chamber through the position where the valve element is disposed.

  Further, in the pump device of the present invention, the drain flow path (18) is formed to communicate with the outside vertically downward from a position at the lowest position in the gravitational direction in the storage chamber (14), The valve body (24) is biased upward based on the fluid pressure acting from the outside through the drain flow path (18), so that the valve seat (21) of the drain flow path (18) And contact with the valve seat (21) of the drain channel (18) according to gravity.

  According to the above configuration, when a fluid pressure acts via the drain flow path, the valve body closes the drain flow path by urging the valve body upward by the fluid pressure. On the other hand, when the fluid pressure does not act through the drain channel, the valve body is arranged at a position separated from the valve seat of the drain channel according to gravity to open the drain channel. That is, the configuration in which the valve body appropriately closes the drain flow path based on the fluid pressure acting from the outside of the apparatus can be easily realized while reducing the number of parts.

In the pump device of the present invention, the restricting means (20) is made of a material having a specific gravity lighter than the specific gravity of the fluid.
According to the said structure, the material of specific gravity lighter than the specific gravity of the fluid which enters into a drain flow path is applied to the valve body and sliding member which comprise a control means. Therefore, when the fluid suddenly enters the drain channel, the drain channel can be closed by promptly moving the valve element upward. Further, when the fluid gradually enters the drain channel, the drain channel can be closed by moving the valve body according to the fluctuation of the fluid surface by buoyancy.

Further, in the pump device of the present invention, the drain channel (18) is formed with locking portions (22, 25) that can be locked with respect to the regulating means (20) from below in the direction of gravity.
According to the said structure, it can suppress by a latching | locking part that a control means falls out from the inside of a drain flow path.

  Further, in the pump device of the present invention, a lid capable of covering the opening (18a) of the drain channel (18) at a position spaced below the locking portion (25) in the drain channel (18). A member (26) is provided, and a small hole (27) that allows the brake fluid to pass therethrough is formed through the lid member (26).

  According to the said structure, the cover member which can cover the opening is provided below the latching | locking part in a drain flow path. For this reason, the lid member can restrict the entry of such fluid into the drain channel when the fluid containing the foreign substance enters from the outside through the opening of the drain channel. The brake fluid flowing down along the inner surface of the drain flow path can be allowed to be discharged to the outside through a small hole.

  In the pump device of the present invention, the movable member (17) is a piston (17) that reciprocates so as to increase or decrease the volume of the pump chamber, and the storage chamber (14) is the piston (17). And is separated from the pump chamber.

  In the pump device of the present invention, the movable member (37, 40) includes a drive gear (40) coupled to the output shaft (13a) of the motor (13) so as to be capable of transmitting power, and the drive gear. The pump chamber is defined by a meshing space between the drive gear (40) and the driven gear (37), and the storage chamber is formed by the driven gear (37) meshing with (40). The volume of the pump chamber increases and decreases with the rotation of the output shaft (13a) of the motor (13), which is separated from the pump chamber via a drive gear (40).

<First Embodiment>
Hereinafter, a first embodiment in which the present invention is embodied in a pump device mounted on a vehicle brake control device will be described with reference to FIGS. 1 and 2.

  As shown in FIGS. 1 and 2, the pump device 11 according to the present embodiment includes a pump case 12 and a motor 13 assembled to a side surface of the pump case 12. A motor cam chamber 14 is formed in the pump case 12 as a storage chamber for accommodating the distal end side of the output shaft 13 a of the motor 13, and the output shaft 13 a of the motor 13 is located at a boundary portion between the motor cam 14 and the motor 13. A bearing 15 that rotatably supports the shaft 15 is disposed. Further, an eccentric cam 16 is attached to the tip of the output shaft 13a of the motor 13 in the motor cam chamber 14, and the eccentric cam 16 is connected to the end of a piston 17 as a movable member so as to be able to transmit power. . That is, when the output shaft 13a rotates as the motor 13 is driven, the eccentric cam 16 reciprocates the piston 17 in the horizontal direction (direction orthogonal to the paper surface in FIG. 1), thereby causing a pump chamber (not shown). ) Volume increases or decreases. In the process of increasing or decreasing the pressure in the pump chamber, the brake fluid in the wheel cylinder corresponding to each wheel is sucked into the pump chamber and the brake fluid sucked into the pump chamber is returned to the master cylinder side. It has become.

  Further, from the position at the lowest position in the direction of gravity in the motor cam chamber 14, the drain flow path 18 having a circular cross section that communicates the inside of the motor cam chamber 14 and the outside of the pump case 12 (that is, the outside of the apparatus) is vertically downward It is formed towards. On the lower end side of the drain flow path 18, a large volume valve chamber 19 having a larger cross-sectional shape than other portions in the drain flow path 18 is formed enlarged. In the valve chamber 19, the brake fluid leaked from the pump chamber side to the motor cam chamber 14 is discharged to the outside of the pump case 12, and the regulation for restricting the ingress of fluid other than brake fluid such as water from the outside. A valve member 20 that functions as a means is accommodated.

  Further, a tapered surface 21 having a truncated cone shape is formed on the upper inner surface of the valve chamber 19 to gradually reduce the cross-sectional shape of the valve chamber 19 toward the motor cam chamber 14 in the axial direction (vertical direction) of the drain flow path 18. ing. In the present embodiment, the tapered surface 21 functions as a valve seat for seating (contacting) the valve member 20 from below. Note that support claws 22 serving as locking portions that form protrusions toward the radial center from a plurality of circumferential locations (two locations in the figure) in the opening 18a on the lower end side of the drain channel 18 are provided. The valve member 20 is supported by the support claw 22 so as to be prevented from falling out of the drain flow path 18.

Next, the valve member 20 which is a main part of the present invention will be described in detail.
As shown in FIGS. 1 and 2, the valve member 20 includes a sliding member 23 that slides against the inner surface of the drain channel 18 while sealing the motor cam chamber 14 side of the drain channel 18, and the sliding member. A valve body 24 that is positioned above 23 and that can contact the tapered surface 21 of the valve chamber 19 to close the drain flow path 18 is integrally formed.

  The sliding member 23 is made of a porous and flexible rubber sponge or the like, and can absorb and hold the brake fluid in a gap formed by fine holes. Therefore, the sliding member 23 can maintain a liquid-tight state in which the gap is filled with the brake fluid leaked from the pump chamber side to the motor cam chamber 14.

  The valve body 24 is formed in a hemispherical shape having a diameter slightly larger than the diameter of the drain flow path 18. The valve body 24 moves upward together with the sliding member 23 that receives the fluid pressure of the fluid such as water that has entered the drain flow path 18, and the upper spherical surface is formed on the tapered surface 21 of the valve chamber 19. It is possible to close the drain flow path 18 by contact. The sliding member 23 can smoothly slide with respect to the inner surface of the valve chamber 19 because the brake fluid absorbed and held functions as lubricating oil. The sliding member 23 and the valve body 24 are made of a material having a specific gravity that is lighter than the specific gravity of the fluid entering the drain channel 18 (for example, a synthetic resin material).

  Then, next, focusing on the action of the valve member 20 provided in the drain flow path 18 of the pump device 11 with respect to the action of the pump device 11 mounted on the vehicle brake control device configured as described above. This will be described below.

  In the vehicle brake control device, when the pump is driven, the brake fluid in the pump chamber may leak into the motor cam chamber 14 through the clearance between the outer peripheral surface of the piston 17 and the inner surface of the cylinder (not shown). If the brake fluid leaks in this way, the brake fluid collects at a position at the lowest position in the direction of gravity in the motor cam chamber 14, that is, a position where the drain flow path 18 is formed.

  Then, the brake fluid collected at the lowermost position in the motor cam chamber 14 flows down along the inner surface of the drain flow path 18 and then reaches the valve chamber 19. Then, the brake fluid that has reached the position where the valve member 20 is disposed is absorbed by the sliding member 23. Furthermore, when the total amount of the brake fluid absorbed by the sliding member 23 exceeds the void volume of the sliding member 23, the brake fluid gradually oozes out from the sliding member 23 according to gravity, and is discharged and discharged to the outside.

  Incidentally, the pump device 11 in the vehicle brake control device is disposed at the bottom of the vehicle. For this reason, for example, a fluid other than a small amount of brake fluid (for example, splash water) may enter the drain flow path 18 from the outside due to factors such as being exposed to the splash water during traveling of the vehicle. If a fluid such as water flows into the drain channel 18 as described above, the fluid is trapped by the sliding member 23 and then discharged to the outside of the drain channel 18 according to gravity. Since the brake fluid leaked into the motor cam chamber 14 is always held in the gap of the sliding member 23, the sliding member 23 always reliably traps the ingress of fluid such as water from the outside. Is possible.

  In addition, a large amount of fluid such as water may suddenly enter the drain flow path 18 from the outside due to factors such as traveling on a rough road where the vehicle is submerged. If a large amount of fluid such as water suddenly enters the drain flow path 18 in this way, the sliding member 23 on which the high-pressure fluid pressure is applied is supported by the support claw 22 at the lower end position of the valve chamber 19. The inside of the valve chamber 19 is quickly raised by sliding along the inner surface of the valve chamber 19 from the state of being supported by (FIG. 2A).

  Then, the valve body 24 moves upward together with the sliding member 23 and quickly closes the drain flow path 18 when it rises to a position where it contacts the tapered surface 21 of the valve chamber 19 (FIG. 2B). ). Therefore, a fluid such as water that has entered the drain channel 18 is blocked at a position below the tapered surface 21 of the valve chamber 19, and then flows down to the outside along the inner surface of the drain channel 18 according to gravity. Is done.

  Also, a large amount of fluid may enter the drain channel 18 from the outside little by little without accompanying a high fluid pressure. If a large amount of fluid gradually enters the drain channel 18 in this way, the sliding member 23 and the valve body 24 are made of a material having a specific gravity lighter than the specific gravity of the fluid. From the state of being supported by the support claw 22 at the lower end position of the valve chamber 19 (FIG. 2A), the inside of the valve chamber 19 is gradually moved by floating on the fluid surface of the fluid entering the drain channel 18. To rise.

  Then, when the fluid amount reaches a predetermined value (that is, when the fluid surface reaches a position directly below the tapered surface 21 of the valve chamber 19), the valve body 24 comes into contact with the tapered surface 21 of the valve chamber 19 and drains. The flow path 18 is closed (FIG. 2B). Therefore, the fluid that has entered the drain channel 18 is blocked at a position below the tapered surface 21 of the valve chamber 19, and then flows down to the outside along the inner surface of the drain channel 18 according to gravity.

  As described above, the valve member 20 can exert a waterproof effect adapted to a more severe external environment by appropriately closing the drain passage 18 by the valve body 24 based on the fluid pressure acting from the outside. It has become.

According to the present embodiment, the following effects can be obtained.
(1) In the above embodiment, when brake fluid leaks from the pump chamber side to the motor cam chamber 14, the brake fluid is absorbed by the sliding member 23 in the process of flowing down in the drain flow path 18. The brake fluid absorbed by the sliding member 23 is discharged to the outside by gradually oozing out from the sliding member 23 according to gravity. On the other hand, when a fluid (for example, water) other than a small amount of brake fluid enters the drain channel 18 from the outside of the pump device 11 due to factors such as being exposed to splashing water, the fluid that has entered is trapped by the sliding member 23. Therefore, such a fluid does not enter the motor cam chamber 14 through the drain flow path 18. In addition, when a large amount of fluid enters the drain passage 18 from the outside due to, for example, traveling on a rough road where the vehicle is submerged, the valve body 24 urged upward by the fluid pressure of the entering fluid. Contacts the tapered surface 21 of the valve chamber 19 to close the drain flow path 18. That is, the valve member 20 can exhibit a waterproof effect adapted to a more severe external environment by the valve body 24 appropriately closing the drain flow path 18 based on the fluid pressure acting from the outside. Moreover, the sliding member 23 can trap the fluid more effectively by absorbing the brake fluid and becoming liquid-tight. Moreover, since the sliding member 23 and the valve body 24 are integrally formed, the valve member 20 can reduce the number of parts compared with the case where these members are provided separately, and the pump apparatus 11. Assembling property can be improved. Therefore, with a simple configuration, the brake fluid leaking from the pump chamber to the motor cam chamber 14 is discharged to the outside of the device, and the entrance of fluid other than brake fluid such as water to the motor cam chamber 14 from the outside of the device is suppressed. Can do.

  (2) In the above embodiment, the valve body 24 is disposed on the motor cam chamber 14 side which is the back side (upper side) of the drain flow path 18 with respect to the sliding member 23. Therefore, when the sliding member 23 located below the valve body 24 traps foreign matter such as dust that has entered the drain flow path 18, the foreign matter can be prevented from reaching the position where the valve body 24 is disposed. . Therefore, it can suppress that the sealing function of the valve body 24 falls with a foreign material adhering to the valve body 24 or the taper surface 21. FIG. Since the brake fluid leaked into the motor cam chamber 14 is always absorbed and held in the sliding member 23 in the course of flowing down the drain flow path 18, the brake fluid makes the sliding member 23 liquid-tight. The sealing function of the sliding member 23 can be enhanced.

  (3) In the above embodiment, when a fluid pressure such as water entering from the outside via the drain flow path 18 acts, the valve body 24 is biased upward by the fluid pressure and is a tapered surface of the valve chamber 19. The drain channel 18 is closed by abutting on the channel 21. On the other hand, the valve body 24 is arranged at a position separated from the tapered surface 21 of the valve chamber 19 according to gravity when fluid pressure such as water entering from the outside via the drain flow path 18 does not act. 18 is released. Therefore, a configuration in which the valve body 24 appropriately closes the drain flow path 18 based on the fluid pressure acting from the outside can be easily realized while reducing the number of components.

  (4) In the said embodiment, the valve member 20 is formed with the material of specific gravity lighter than the specific gravity of the fluid which approachs from the outside. Therefore, when a fluid such as water suddenly enters the drain channel 18 from the outside, the drain channel 18 can be closed by rapidly moving the valve body 24 by buoyancy. In addition, when a fluid such as water gradually enters the drain channel 18 from the outside, the drain channel 18 can be closed by moving the valve body 24 in accordance with the fluctuation of the fluid surface.

<Second Embodiment>
Next, a second embodiment of the present invention will be described with reference to FIG. The second embodiment is different from the first embodiment in the following points. That is, in the pump device 11 in the present embodiment, the lid member 26 is attached to the opening 18 a on the lower end side of the drain flow path 18. Therefore, members having the same configurations as those of the first embodiment are denoted by the same reference numerals, and redundant description thereof is omitted.

  As shown in FIG. 3A and FIG. 3B, in the pump device 11 of the present embodiment, the valve chamber 19 protrudes from a midway in the up-down direction toward the radially inner side. A step portion 25 is formed as a locking portion, and the step portion 25 supports the sliding member 23 from below. A flat lid member 26 is attached to the opening 18a on the lower end side of the valve chamber 19 so as to cover the opening 18a. The lid member 26 connects the inside and outside of the drain passage 18 with each other. A small hole 27 communicating therewith is formed in the vertical direction.

  Therefore, in this embodiment, the brake fluid leaked from the pump chamber side to the motor cam chamber 14 flows down along the inner surface of the drain flow path 18 and then reaches the position where the valve member 20 is disposed, and then the sliding member 23. It is absorbed more and makes the sliding member 23 liquid-tight. Then, the brake fluid gradually oozes from the sliding member 23 according to gravity, thereby further flowing down along the inner surface of the valve chamber 19, and is discharged to the outside through the small hole 27 of the lid member 26.

  In addition, when a fluid such as water containing foreign matter tries to enter the drain channel 18 from the outside, the entry of such fluid is restricted by the lid member 26. Therefore, when such fluid enters the drain flow path 18, the lid member 26 prevents the occurrence of a situation in which foreign matter contained in the fluid causes clogging in the gap of the sliding member 23. Is done. The sliding member 23 is supported by the step portion 25 of the valve chamber 19 at a position spaced upward in the axial direction (vertical direction) with respect to the opening 18 a on the lower end side of the drain flow path 18. Therefore, even if a fluid such as water containing foreign matter enters the drain channel 18 (in this case, the valve chamber 19) from the outside through the small hole 27 of the lid member 26, It is possible to suppress the fluid from reaching the position where the sliding member 23 is locked to the step portion 25.

Therefore, according to the present embodiment, in addition to the effects (1) to (4) in the first embodiment, the following effects can be further obtained.
(5) In the above embodiment, the lid member 26 is provided on the lower end side of the drain flow path 18 so as to cover the opening 18a. Therefore, the lid member 26 can restrict the fluid such as water containing foreign matter from entering the drain channel 18. On the other hand, since the small hole 27 is formed through the lid member 26, the brake fluid flowing down along the inner surface of the drain flow path 18 can be discharged to the outside through the small hole 27.

  (6) In the above-described embodiment, the valve chamber 19 is formed with the step portion 25 projecting radially inward, and the sliding member 23 is more axial than the opening 18 a on the lower end side of the drain flow path 18. The step portion 25 is supported at a position spaced upward in the direction (vertical direction). Therefore, even if a fluid such as water containing foreign matter enters the drain channel 18 (inside the valve chamber 19) from the outside through the small hole 27 of the lid member 26, such fluid does not slide. It can suppress reaching to the arrangement position of the moving member 23.

<Third Embodiment>
Next, a third embodiment of the present invention will be described with reference to FIGS. The configuration of the third embodiment is different from the first embodiment in the following points. That is, the pump device 11 in the present embodiment applies a gear pump mechanism as a pump mechanism for sucking and discharging brake fluid, and the sliding member 23 is disposed closer to the motor cam chamber 14 than the valve body 24 in the drain flow path 18. Has been. Therefore, members having the same configurations as those of the first embodiment are denoted by the same reference numerals, and redundant description thereof is omitted.

  As shown in FIGS. 4 and 5, the pump device 11 according to the present embodiment includes a pump case 12 and a motor 13 assembled to a side surface of the pump case 12. In the pump case 12, a first block 31 having a columnar shape, a second block 32 having a columnar shape, and a disk-like plate 33 sandwiched between the blocks 31 and 32 are integrated by welding. Has a configuration.

  In the center of the surface of the first block 31 facing the plate 33, a recess 31a for receiving the tip of the output shaft 13a of the motor 13 is formed. A through hole 34 through which the output shaft 13 a of the motor 13 passes is formed at the center of the second block 32, and a recess 35 having a larger diameter than the through hole 34 is formed on the base end side of the output shaft 13 a of the through hole 34. Is formed. A bearing 15 for rotatably supporting the output shaft 13a of the motor 13 is fitted to the base end side (left side in FIG. 4) in the recess 35. In the present embodiment, the recess 31 a of the first block 31, the through hole 34 of the second block 32, and the recess 35 form a storage chamber for storing the output shaft 13 a of the motor 13.

  A rotor chamber 36 having a diameter larger than that of the output shaft 13a of the motor 13 is formed in the center of the plate 33, and an outer gear 37 as a driven gear having inner teeth formed on the inner peripheral surface is formed in the rotor chamber 36. It is housed rotatably. On the other hand, a key groove 38 is formed at a position corresponding to the rotor chamber 36 on the outer peripheral surface of the output shaft 13 a of the motor 13, and a key 39 is fitted in the key groove 38. An inner gear 40 as a drive gear having external teeth formed on the outer peripheral surface via the key 39 is supported by the output shaft 13a of the motor 13 so as to be integrally rotatable in a state of meshing with the outer gear 37.

  The outer gear 37 and the inner gear 40 are configured such that a plurality of meshing spaces 41 are formed between the inner gear 40 and the outer gear 40 when the inner gear and the outer gear mesh with each other. As the output shaft 13a of the motor 13 rotates, the volume of the meshing space 41 between the two increases and decreases, and the brake fluid is sucked from the suction pipe 42 formed in the first block 31 in the meshing space 41. The brake fluid is discharged from the meshing space 41 to the discharge conduit 43 formed in the second block 32. In this respect, the outer gear 37 and the inner gear 40 function as a movable member that rotates in conjunction with the output shaft 13a of the motor 13, and the meshing space 41 functions as a pump chamber.

  Further, from the position at the lowest position in the direction of gravity in the recess 35, the drain flow path 18 having a circular cross section that communicates the inside of the recess 35 and the outside of the pump case 12 (that is, the outside of the apparatus) is vertically downward. It is formed towards. A valve member 19 as a restricting means is accommodated in the valve chamber 19 formed on the lower end side of the drain flow path 18.

Next, the valve member 20 that is a main part of the present invention will be described in detail.
As shown in FIGS. 5A and 5B, also in the pump device 11 of the present embodiment, the valve member 20 can block the drain flow path 18 by contacting the tapered surface 21 of the valve chamber 19. The valve body 24 and the sliding member 23 that slides against the inner surface of the drain channel 18 while sealing the recess 35 side of the drain channel 18 are integrally formed.

  The valve body 24 is designed to have a substantially truncated cone shape in which the diameter on the lower end side is larger than the diameter of the drain flow path 18, and receives the fluid pressure of the fluid that has entered the drain flow path 18. The drain flow path 18 can be closed by moving upward and contacting the tapered surface 21 of the valve chamber 19 with the inclined surface 24a having a conical surface. In addition, from a plurality of circumferential locations (only one location is shown in the figure) in the opening 18a on the lower end side of the valve chamber 19, projecting pawls 22 projecting toward the center in the radial direction are provided. The valve member 20 is prevented from coming off by the valve body 24 being supported by the support claws 22.

  From the upper surface of the valve body 24, a rod portion 28 having a cylindrical shape smaller than the inner diameter of the drain channel 18 is erected upward so as to be inserted into the drain channel 18. In addition, a neck portion 28a having a smaller diameter than other portions of the rod portion 28 is formed in the vicinity of the upper end portion of the rod portion 28, and the sliding member 23 is attached to the neck portion 28a.

  The sliding member 23 is designed so as to form an annular shape having substantially the same diameter as that of the drain flow path 18. The sliding member 23 is attached to the neck portion 28 a of the rod portion 28 extending upward from the valve body 24, thereby sealing the region above the sliding member 23 in the drain channel 18. is doing. In addition, the sliding member 23 is comprised by the felt which laminated | stacked the fiber excellent in the liquid absorptivity, and can absorb and hold | maintain a brake fluid. Therefore, the sliding member 23 can maintain a state containing brake fluid leaking from the pump chamber.

  Then, next, focusing on the action of the valve member 20 provided in the drain flow path 18 of the pump device 11 with respect to the action of the pump device 11 mounted on the vehicle brake control device configured as described above. This will be described below.

  In the vehicular brake control device, when the pump is driven, the brake fluid sucked into the meshing space 41 between the inner gear 40 and the outer gear 37 has a clearance between the inner gear 40 and both the blocks 31 and 32, and There is a possibility of leakage into the recess 35 through a clearance between the inner peripheral surface of the through hole 34 of the two blocks 32 and the outer peripheral surface of the output shaft 13 a of the motor 13. If the brake fluid leaks into the recess 35 in this way, the brake fluid flows down along the inner surface of the drain flow path 18 and then reaches the position where the sliding member 23 is disposed in the valve member 20. It is absorbed by the sliding member 23 at the time. The brake fluid gradually oozes out from the sliding member 23 according to gravity, thereby flowing down along the inner surface of the drain channel 18 and finally flowing down and discharged to the outside.

  Further, when a fluid other than a small amount of brake fluid enters the drain passage 18 from the outside, the fluid is trapped by the sliding member 23 that seals the concave portion 35 side in the drain passage 18 and is subjected to gravity. It is discharged to the outside of the drain channel 18. Since the brake fluid that has flowed down along the inner surface of the drain channel 18 after leaking into the recess 35 is always absorbed and held in the sliding member 23, the sliding member 23 is made liquid-tight. It is possible to always reliably trap the entry of fluid from the outside.

  Further, when a large amount of fluid suddenly enters the drain flow path 18, high pressure fluid pressure acts on the valve body 24 from below, so that the valve body 24 is supported at the lower end position of the valve chamber 19. The valve chamber 19 is quickly raised from the state supported by the valve 22 (FIG. 5A). Then, the valve body 24 quickly closes the drain flow path 18 when the inclined surface 24a rises to a position where it contacts the tapered surface 21 of the valve chamber 19 (FIG. 5B). Therefore, the fluid that has entered the drain channel 18 is blocked at a position below the tapered surface 21 of the valve chamber 19, and then flows down to the outside along the inner surface of the drain channel 18 according to gravity. The valve body 24 is appropriately supplied with brake fluid absorbed and held by the sliding member 23 so that the airtightness (sealability) of the valve body 24 is enhanced.

  When a large amount of fluid enters the drain flow path 18 little by little without high fluid pressure, the sliding member 23 and the valve body 24 are materials having a specific gravity lighter than the specific gravity of the entering fluid. Therefore, by floating on the fluid surface of the fluid entering the drain channel 18 from the state supported by the support claw 22 at the lower end position of the valve chamber 19 (FIG. 5A). The valve chamber 19 is gradually raised. The valve body 24 has a slant surface 24 a that contacts the tapered surface 21 of the valve chamber 19 when the fluid amount reaches a predetermined value (that is, when the fluid surface reaches the tapered surface 21 of the valve chamber 19). The drain channel 18 is closed by contact (FIG. 5B). Therefore, the fluid that has entered the drain channel 18 is blocked at a position below the tapered surface 21 of the valve chamber 19, and then flows down to the outside along the inner surface of the drain channel 18 according to gravity.

According to the present embodiment, the following effects can be further obtained.
(7) In the above-described embodiment, the sliding member 23 is disposed on the recessed portion 35 side which is the back side (upper side) of the drain channel 18 than the valve body 24. Therefore, the fluid can be restricted from reaching the recess 35 by trapping the fluid that passes through the position where the valve body 24 is disposed and enters the recess 35. The sliding member 23 always absorbs and holds the brake fluid that has flowed down along the inner surface of the drain passage 18 after leaking from the meshing space 41 between the inner gear 40 and the outer gear 37 to the concave portion 35 side. Thus, the airtightness (sealability) of the valve body 24 can be improved by appropriately supplying brake fluid from the liquid-tight sliding member 23 to the lower valve body 24.

In addition, you may change the said embodiment as follows.
In the first and second embodiments, the valve member 20 may be configured such that the sliding member 23 is disposed closer to the motor cam chamber 14 than the valve body 24.

In the third embodiment, the valve member 20 may be configured such that the valve body 24 is disposed closer to the concave portion 35 than the sliding member 23.
In each of the above embodiments, the material constituting the sliding member 23 is not limited to sponge or felt, and may be other materials as long as the material has liquid absorbency.

  -In the said 2nd Embodiment, without providing the level | step-difference part 25 which latches the sliding member 23 of the valve member 20 from the downward direction in the valve chamber 19, as a latching | locking part with which the cover member 26 supports the valve member 20 It may be configured to function.

  In the third embodiment, a lid member 26 is provided on the lower end side of the valve chamber 19 so as to cover the opening 18a, and the lid member 26 penetrates through the small hole 27 that communicates the inside and outside of the drain flow path 18. It is good also as a structure to form.

In each of the above embodiments, the valve body 24 may be made of a material having a specific gravity heavier than the specific gravity of the fluid entering the drain flow path 18.
In each of the above embodiments, the drain flow path 18 may communicate between the motor cam chamber 14 and the outside in a non-linear shape or an oblique shape with respect to the vertical direction.

  In the first and second embodiments, the valve chamber 20 shown in FIGS. 5A and 5B may be disposed in the valve chamber 19, and in the third embodiment, the valve member 20 shown in FIG. (B) or the valve member 20 shown in FIGS. 3 (a) and 3 (b) may be provided.

The schematic sectional drawing of the pump apparatus in 1st Embodiment. (A) The principal part expanded sectional view of the pump apparatus in 1st Embodiment when a valve member is valve-opening, (b) is the principal part expanded cross section of the pump apparatus of 1st Embodiment when a valve member is valve closing. Figure. (A) The principal part expanded sectional view of the pump apparatus of 2nd Embodiment when a valve member is valve opening, (b) is the principal part expanded cross section of the pump apparatus of 2nd Embodiment when a valve member is valve closing. Figure. The schematic sectional drawing of the pump apparatus in 3rd Embodiment. (A) The principal part expanded sectional view of the pump apparatus of 3rd Embodiment when a valve member is valve opening, (b) is the principal part expanded cross section of the pump apparatus of 3rd Embodiment when a valve member is valve closing. Figure.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 11 ... Pump apparatus, 13 ... Motor, 13a ... Output shaft, 14 ... Motor cam chamber as a storage chamber, 17 ... Piston as a movable member, 18 ... Drain flow path, 18a ... Opening, 20 ... Valve member as regulation means, DESCRIPTION OF SYMBOLS 21 ... Tapered surface as a valve seat, 22 ... Bearing claw as a latching part, 23 ... Sliding member, 24 ... Valve body, 25 ... Step part as a latching part, 26 ... Lid member, 27 ... Small hole, Reference numeral 31a: a concave portion constituting the accommodating chamber, 34: a through hole constituting the accommodating chamber, 35: a concave portion constituting the accommodating chamber, 37: an outer gear as a movable member, 40: an inner gear as a movable member.

Claims (9)

A pump chamber that sucks and discharges brake fluid based on a pump drive of the movable member (17, 37, 40) is separated from the pump chamber via the movable member (17, 40), and the movable member (17, 40). ) Including a storage chamber (14) for storing the output shaft (13a) of the motor (13) coupled so as to be capable of transmitting power, and a drain channel (18) communicating from the storage chamber (14) to the outside. Pump device (11),
A restriction that allows the brake fluid to be discharged from the storage chamber (14) to the outside and restricts the entry of fluid from the outside to the storage chamber (14) at a midpoint of the drain flow path (18). Means (20) are provided,
The regulating means (20)
The valve seat (21) formed in the drain channel (18) is positioned below the gravitational direction and is biased upward in the gravitational direction based on the fluid pressure acting through the drain channel (18). A valve body (24) that comes into contact with the valve seat (21) so as to close the drain passage (18);
The valve body (24) is formed integrally with the inner surface of the drain channel (18), can slide along the inner surface of the drain channel (18), and can guide the valve body (24) along the drain channel (18). A pump device comprising a sliding member (23) made of a material capable of absorbing the brake fluid in a sliding contact portion with the drain flow path (18). The pump device according to claim 1,
The regulating means (20) is arranged so that the sliding member (23) is located on the opposite side of the accommodating chamber (14) from the valve body (24) in the middle of the drain flow path (18). A pump device characterized by being provided. The pump device according to claim 1,
The regulating means (20) is provided so that the sliding member (23) is positioned closer to the storage chamber (14) than the valve body (24) in the middle of the drain flow path (18). A pump device characterized by. In the pump device according to any one of claims 1 to 3,
The drain channel (18) is formed so as to communicate with the outside vertically downward from a position that is the lowest in the direction of gravity in the storage chamber (14),
The valve body (24) is biased upward based on the fluid pressure acting from the outside through the drain flow path (18), so that the valve seat (21) of the drain flow path (18) And a pump device characterized in that the pump device is separated from the valve seat (21) of the drain flow path (18) according to gravity. In the pump device according to any one of claims 1 to 4,
The pump device according to claim 1, wherein the regulating means (20) is made of a material having a specific gravity lighter than a specific gravity of the fluid. In the pump device according to any one of claims 1 to 5,
The pump device characterized in that the drain channel (18) is formed with locking portions (22, 25) that can be locked to the regulating means (20) from below in the direction of gravity. The pump device according to claim 6,
A lid member (26) capable of covering the opening (18a) of the drain channel (18) is provided at a position spaced below the locking portion (25) in the drain channel (18), A pump device characterized in that a small hole (27) allowing passage of the brake fluid is formed through the lid member (26). In the pump device according to any one of claims 1 to 7,
The movable member (17) is a piston (17) that reciprocates to increase or decrease the volume of the pump chamber,
The pump device according to claim 1, wherein the storage chamber (14) is separated from the pump chamber via the piston (17). In the pump device according to any one of claims 1 to 7,
The movable members (37, 40) are connected to a drive gear (40) capable of transmitting power to the output shaft (13a) of the motor (13);
A driven gear (37) meshing with the drive gear (40),
The pump chamber is defined by a meshing space between the drive gear (40) and the driven gear (37), and the storage chamber is separated from the pump chamber via the drive gear (40),
The pump device characterized in that the volume of the pump chamber increases or decreases as the output shaft (13a) of the motor (13) rotates.

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