JP2007263116A - Rotary pump and brake apparatus having the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce a loss torque due to the contact of an inner rotor and an outer rotor on the end surfaces of side plates. <P>SOLUTION: In the portion of a rotary pump mechanically sealed in the same manner as between the outer rotor and a second side plate 72, an oil groove 72c is formed to reduce the contact area of the axial end surface of the outer rotor on the second side plate 72 by the area of an oil groove 72c so as to reduce a contact resistance. A discharge pressure is introduced into the oil groove 72c to push back the outer rotor to the first side plate side by the discharge pressure in the oil groove 72c. Since a force with which the outer rotor is pressed against the second side plate 72 is reduced, the loss torque can be reduced. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a rotary pump that sucks and discharges fluid and a brake device using the rotary pump, and is particularly suitable for application to an internal gear pump such as a trochoid pump.

  Conventionally, as an internal gear type rotary pump such as a trochoid pump, there is one disclosed in Patent Document 1. This rotary pump is composed of an inner rotor having outer teeth on the outer periphery, an outer rotor having inner teeth on the inner periphery, a casing for housing these outer rotor and inner rotor, and the like. The inner rotor and the outer rotor are arranged in the casing in a state where the inner teeth and the outer teeth are engaged with each other and a plurality of gaps are formed by these teeth.

  If the line passing through the central axes of the inner rotor and the outer rotor is the center line of the pump, suction ports and discharge ports communicating with the plurality of gaps are provided on both sides of the center line. When the pump is driven, the central axis of the inner rotor is used as a drive shaft, and the inner rotor rotates through the drive shaft, and the outer rotor is also rotated in the same direction due to the meshing of the outer teeth and the inner teeth. At this time, the volume of each gap portion changes in size while the outer rotor and the inner rotor make one rotation, and the oil is sucked from the suction port, and the oil is discharged from the discharge port.

The axial end face of the rotary pump is sealed by a resin member made of resin, and the resin member is pressed by an elastic member made of an elastic body such as rubber to serve as a sealing mechanism. It has become.
Japanese Unexamined Patent Publication No. 2000-179466

  Adopting a sealing method using resin sealing means on both axial end faces as in the above publication causes an increase in cost. For this reason, only one end surface side is sealed with a resin sealing means, and the other end surface side is a mechanical seal that directly presses the inner rotor and outer rotor against the second side plate, thereby reducing costs. Conceivable.

  This mechanical seal has a structure in which a metal inner rotor and an outer rotor are strongly pressed against a metal side plate by an elastic force of a sealing material or the like to seal. Therefore, if the loss torque of the sliding surfaces of the outer rotor, the inner rotor, and the side plate is large, the pump discharge capacity is affected, and the motor size must be increased.

  In addition, if there are parts with large and small rotational torque loss on the sliding surface between the outer rotor and inner rotor and the side plate, heat is generated at the part with large torque loss due to high-speed or long-time rotation of the pump. A negative effect on the pump discharge capacity due to the expansion and expansion of the heat generation part is also considered.

  The present invention has been made in view of the above problems, and uses a rotary pump in which loss torque due to contact between the inner rotor and outer rotor and the end face of the casing (side plate) is reduced and / or the loss torque is made uniform. An object is to provide a brake device.

Therefore, in order to achieve the above object, the following technical means are adopted. In the first aspect of the present invention, an outer rotor having an inner tooth portion (51a) on the inner periphery and an inner rotor (52 having an outer tooth portion (52a) on the outer periphery and rotating about the drive shaft (54). ), And a rotating part in which a plurality of gaps (53) are formed between the meshing between the inner tooth part and the outer tooth part, and a first axially arranged end face side of the rotating part. And a second side plate (72) that is disposed on the other axial end face side of the rotating portion and that has a contact surface with the axial end faces of the outer rotor and the inner rotor for mechanical sealing. A casing (50) formed to cover the rotating part, a suction port (60) provided in the casing for sucking fluid into the rotating part, and a discharge port for discharging fluid from the rotating part (61) and Sealing means for dividing the space in which the rotating part inside the casing is contained into a low-pressure side space connected to the suction port and a high-pressure side space connected to the discharge port, and a shaft of the outer rotor An oil groove (72c) that is provided in a portion that does not overlap the internal tooth portion of the portion of the second side plate that faces the direction end face, and that extends over the high-pressure side space and does not cross over the low-pressure side space. ) .

That is, according to the present invention, the oil groove is formed in at least one of the outer rotor and the second side plate in a portion that is mechanically sealed as between the outer rotor and the second side plate. The contact area between the axial end surface of the outer rotor and the second side plate is reduced. Therefore, the contact resistance between the outer rotor and the second side plate can be reduced.

In addition, as described in claim 2 , the high-pressure side space and the low-pressure side space are provided in both the plurality of gap portions and the portion between the outer circumference of the outer rotor and the casing, and the plurality of gaps. The oil groove may be formed in a range in which the portion of the high pressure side space of the portion and the portion of the high pressure side space between the outer circumference of the outer rotor and the casing overlap in the radial direction of the rotating portion. Good.

  The flow of the fluid between the outer rotor and the second side plate that are mechanically sealed includes the fluid pressure at the plurality of gap portions and the fluid pressure at the portion between the outer circumference of the outer rotor and the casing. In a portion where there is no differential pressure, there is no lubrication other than the movement of the fluid along the polishing bars or the movement of the fluid by the centrifugal force of the rotating body. Conversely, a portion where there is a differential pressure between the fluid pressure at the plurality of gap portions and the fluid pressure at the portion between the outer circumference of the outer rotor and the casing, that is, the high-pressure side space and the low-pressure side space When the positions in the radial direction overlap each other, the fluid moves through the part that is mechanically sealed from the high pressure side to the low pressure side by this differential pressure. Therefore, it is considered that the portion where there is no differential pressure between the fluid pressure in the plurality of gap portions and the fluid pressure in the portion between the outer circumference of the outer rotor and the casing is considered to be the least lubricated. If this is provided, the contact resistance between the outer rotor and the second side plate can be more effectively reduced.

The rotary pump according to the present invention, as shown in claim 3, the brake fluid pressure generating means for generating a brake fluid pressure (1-3) on the basis of the pedaling force, the braking force to the wheel based on the brake fluid pressure Is connected to the braking force generating means (4, 5) and the brake fluid pressure generating means, and is connected to the main pipeline (A) for transmitting the brake fluid pressure to the braking force generating means, and the brake fluid pressure generating means, In order to increase the braking force generated by the braking force generating means, in a brake device having an auxiliary pipeline (D) for supplying brake fluid to the main pipeline side, the suction port is connected to the brake fluid pressure generating means side brake through the auxiliary pipeline. The liquid can be sucked, and the discharge port is arranged so as to discharge the brake liquid toward the braking force generating means through the main pipeline.

  In addition, the code | symbol in the bracket | parenthesis of each said means shows the correspondence with the specific means as described in embodiment mentioned later.

  An embodiment of the present invention will be described. In each embodiment described below, the first embodiment is a reference example, and the second to fourth embodiments correspond to the embodiments of the invention described in the claims.

(First embodiment)
Hereinafter, embodiments shown in the drawings will be described. In FIG. 1, the brake piping schematic of the brake device which applied the trochoid pump as a rotary pump is shown. Hereinafter, the basic configuration of the brake device will be described with reference to FIG. In the present embodiment, the brake device according to the present invention is applied to a vehicle constituting an X-pipe hydraulic circuit having a right front wheel-left rear wheel and a left front wheel-right rear wheel piping system in a front-wheel drive four-wheel vehicle. An example will be described.

  As shown in FIG. 1, the brake pedal 1 is connected to a booster device 2, and the brake pedal force and the like are boosted by the booster device 2. The booster 2 has a push rod or the like that transmits the boosted pedaling force to the master cylinder 3, and the push cylinder presses a master piston disposed in the master cylinder 3 to thereby master cylinder. Pressure is generated. The brake pedal 1, the booster 2, and the master cylinder 3 correspond to brake fluid pressure generating means.

  The master cylinder 3 is connected to a master reservoir 3 a that supplies brake fluid into the master cylinder 3 and stores excess brake fluid in the master cylinder 3.

  The master cylinder pressure is transmitted to the wheel cylinder 4 for the right front wheel FR and the wheel cylinder 5 for the left rear wheel RL via an antilock brake device (hereinafter referred to as ABS). In the following description, the right front wheel FR and the left rear wheel RL side will be described. However, since the same applies to the left front wheel FL and the right rear wheel RR side which are the second piping system, the description will be omitted.

  The brake device is provided with a pipe line (main pipe line) A connected to the master cylinder 3, and the pipe line A is provided with a proportional control valve (PV: proportioning valve) 22. The proportional control valve 22 divides the pipe A into two parts. That is, the pipe A is divided into a pipe A1 that receives the master cylinder pressure between the master cylinder 3 and the proportional control valve 22, and a pipe A2 between the proportional control valve 22 and the wheel cylinders 4 and 5.

  The proportional control valve 22 normally has an action of transmitting the reference pressure of the brake fluid to the downstream side with a predetermined damping ratio when the brake fluid flows in the forward direction. Then, as shown in FIG. 1, by connecting the proportional control valve 22 in reverse, the pipe A2 side becomes the reference pressure.

  Further, in the pipeline A2, the pipeline A is branched into two, one of which is provided with a pressure increase control valve 30 for controlling the increase of the brake fluid pressure to the wheel cylinder 4, and the other is the wheel cylinder. A pressure increase control valve 31 for controlling the increase of the brake fluid pressure to 5 is provided.

  These pressure-increasing control valves 30 and 31 are configured as two-position valves that can control the communication / blocking state by an ABS electronic control unit (hereinafter referred to as ECU). When the two-position valve is controlled to be in communication, the master cylinder pressure or the brake fluid pressure generated by discharging the brake fluid from the pump can be applied to the wheel cylinders 4 and 5. These pressure-increasing control valves 30 and 31 are controlled to be always in communication during normal braking when ABS control is not executed.

  The pressure increase control valves 30 and 31 are provided with safety valves 30a and 31a, respectively, so that brake fluid is removed from the wheel cylinders 4 and 5 side when the brake depression is stopped and the ABS control is finished. It has become.

  Further, an ABS ECU is provided in a pipeline B connecting the pipeline A between the first and second pressure increase control valves 30, 31 and the wheel cylinders 4, 5 and the reservoir hole 20a of the reservoir 20. Depressurization control valves 32 and 33 that can control the communication / blocking state are respectively provided. These pressure reduction control valves 32 and 33 are always cut off in the normal brake state (when the ABS is not operating).

  A rotary pump 10 is disposed between safety valves 10a and 10b in a pipe C connecting the proportional control valve 22, the pressure increase control valves 30 and 31 of the pipe A, and the reservoir hole 20a of the reservoir 20. A motor 11 is connected to the rotary pump 10, and the rotary pump 10 is driven by the motor 11. A detailed description of the rotary pump 10 will be given later.

  In addition, a damper 12 is disposed on the discharge side of the rotary pump 10 in the pipe C in order to reduce the pulsation of the brake fluid discharged by the rotary pump 10. A pipe line (auxiliary pipe line) D is provided so as to connect between the reservoir 20 and the rotary pump 10 and the master cylinder 3, and the rotary pump 10 is connected to the pipe line via the pipe line D. By sucking the brake fluid A1 and discharging it to the pipe A2, the wheel cylinder pressure in the wheel cylinders 4 and 5 is made higher than the master cylinder pressure to increase the wheel braking force. The proportional control valve 22 holds a differential pressure between the master cylinder pressure and the wheel cylinder pressure at this time.

  A control valve 34 is provided in the pipeline D, and the control valve 34 is always cut off during normal braking.

  In addition, a check valve 21 is disposed between the connection part of the pipe C and the pipe D and the reservoir 20 so as not to flow backward from the pipe C to the reservoir 20 due to the hydraulic pressure transmitted from the pipe D at this time. Has been.

  Further, a control valve 40 is provided between the connection point of the pipeline A and the proportional control valve 22 in the pipeline A. The control valve 40 is a two-position valve that is normally in communication. When the master cylinder pressure is lower than a predetermined pressure, the control valve 40 is shut off when the wheel cylinders 4 and 5 are suddenly braked or TRC. The differential pressure between the cylinder side and the wheel cylinder side is maintained.

  Next, FIG. 2A shows a schematic view of the rotary pump 10, and FIG. 2B shows a cross-sectional view taken along the line AA of FIG. 2A. First, the structure of the rotary pump 10 will be described with reference to FIGS. 2 (a) and 2 (b).

  In the rotor chamber 50a of the casing 50 in the rotary pump 10, the outer rotor 51 and the inner rotor 52 are assembled and stored with their respective central axes (points X and Y in the figure) being eccentric. Yes. The outer rotor 51 includes an inner tooth portion 51a on the inner periphery, and the inner rotor 52 includes an outer tooth portion 52a on the outer periphery. The outer rotor 51 and the inner rotor 52 are meshed with each other by forming a plurality of gap portions 53 by the tooth portions 51a and 52a. As can be seen from FIG. 2A, the rotary pump 10 according to the present embodiment is a partition in which a gap portion 53 is formed by the inner tooth portion 51 a of the outer rotor 51 and the outer tooth portion 52 a of the inner rotor 52. It is a multi-tooth trochoid type pump without a plate (crescent). Further, in order to transmit the rotational torque of the inner rotor 52, the inner rotor 52 and the outer rotor 51 have a plurality of contact points.

  As shown in FIG. 2 (b), the casing 50 includes a first side plate portion 71 and a second side plate portion 72 arranged so as to sandwich both rotors 51 and 52 from both sides, and the first, A central plate portion 73 is provided between the second side plate portions 71 and 72 and is provided with a hole for accommodating the outer rotor 51 and the inner rotor 52, thereby forming a rotor chamber 50a. Yes.

  In addition, center holes 71a and 72a communicating with the interior of the rotor chamber 50a are formed at the center of the first and second side plates 71 and 72, and the drive shaft 54 is fitted into these center holes 71a. Yes. The outer rotor 51 and the inner rotor 52 are rotatably disposed in the hole of the central plate portion 73. In other words, the rotating portion composed of the outer rotor 51 and the inner rotor 52 is rotatably incorporated in the rotor chamber 50a of the casing 50, the outer rotor 51 rotates about the point X, and the inner rotor 52 sets the point Y. It will rotate as an axis.

  Furthermore, when a line passing through the point X and the point Y serving as the respective rotation axes of the outer rotor 51 and the inner rotor 52 is a center line Z of the rotary pump 10, the center line Z is sandwiched between the first side plate portions 71. On the left and right sides, a suction port 60 and a discharge port 61 communicating with the rotor chamber 50a are formed. The suction port 60 and the discharge port 61 are disposed at positions that communicate with the plurality of gaps 53. The brake fluid from the outside can be sucked into the gap 53 through the suction port 60 and the brake fluid in the gap 53 can be discharged to the outside through the discharge port 61.

  Among the plurality of gap portions 53, the closed portion 53a having the maximum volume and the closed portion 53b having the minimum volume are configured not to communicate with either the suction port 60 or the discharge port 61. The closed portions 53a and 53b hold the differential pressure between the suction pressure at the suction port 60 and the discharge pressure at the discharge port 61.

  The first side plate portion 71 is provided with a conduction path 73a that connects the outer circumference of the outer rotor 51 and the suction port 60, and further, conduction paths 73b and 73c that communicate the outer circumference of the outer rotor 51 and the discharge port 61. Yes. The conduction path 73a is disposed at a position of about 90 degrees from the center line Z toward the suction port 60 with the point X serving as the rotation axis of the outer rotor 51 as the center. The conduction path 73b is formed so as to communicate the gap 53 closest to the confining part 53a and the outer periphery of the outer rotor 51 among the plurality of gaps 53 communicating with the discharge port 61. The conduction path 73 c is formed so as to communicate the gap 53 closest to the confinement part 53 b and the outer periphery of the outer rotor 51 among the plurality of gaps 53 communicating with the discharge port 61. The conduction path 73b and the conduction path 73c are arranged at a position of about 22.5 degrees from the center line Z toward the discharge port 61 with the point X as the center.

  Further, the wall surface of the central plate 73 that forms the hole of the central plate 73 and at a position about 45 degrees from the center line Z toward the suction port 60 with the point X serving as the rotation axis of the outer rotor 51 as the center. A recess 73d and a recess 73e are formed, and seal members 80 and 81 for suppressing the flow of brake fluid on the outer periphery of the outer rotor 51 are provided in the recesses 73d and 73e. Specifically, the seal members 80 and 81 are disposed between the conduction path 71b and the conduction path 71d, and seal the portion where the brake hydraulic pressure is low and the portion where the brake hydraulic pressure is high on the outer periphery of the outer rotor 51. It is supposed to be.

  The seal member 80 includes a substantially cylindrical rubber member 80a and a rectangular parallelepiped Teflon (registered trademark) resin member 80b. The resin member 80 b is pressed by the rubber member 80 a and comes into contact with the outer rotor 51. That is, a slight error occurs in the size of the outer rotor 51 due to a manufacturing error or the like, and this error can be absorbed by the rubber member 80a having an elastic force.

  Further, as shown in FIG. 2B, a groove portion 71 b is formed in the first side plate portion 71. As shown by a two-dot chain line in FIG. 2A, the groove 71b is formed in an annular shape surrounding the drive shaft 54 and has a structure in which the groove width is widened in a predetermined region. Specifically, the center of the groove portion 71 b is eccentric to the suction port 60 side (left side of the drawing) with respect to the shaft center of the drive shaft 54.

  As a result, the groove 71 b passes between the discharge port 61 and the drive shaft 54 and is disposed so as to pass through the portion where the closing portions 53 a and 53 b and the seal members 80 and 81 seal the outer rotor 51. . The groove portion 71b assumes a line connecting the axis of the drive shaft 54 and the center of the groove portion 71b, and the inner rotor 51 and the outer rotor 52 are located at a position where the line intersects the suction port 60 or the discharge port 61. The groove width is increased so as to overlap both. In addition, the groove 71b has a larger groove width in the groove portions 71b and 72b even at the portions overlapping the closed portions 53a and 53b.

  Seal members 100 each having a shape similar to the shape of the groove 71b are disposed in the groove 71b having such a configuration. A schematic diagram of these sealing members 100 is shown in FIG. As shown in this figure, the seal member 100 is configured by forming a predetermined region of an annular member wide.

  The wide portion 100C and the wide portion 100D that are formed to be wide are configured to have a width so as to completely cover the closed portion 53a and the closed portion 53b, respectively, and mainly brake fluid in the closed portions 53a and 53b. Serves as a seal to prevent leakage. Further, the wide portion 100 </ b> C and the wide portion 100 </ b> D also serve to eliminate axial displacement of the outer rotor 51 and the inner rotor 52.

  These seal members 100 are constituted by an elastic member 100a made of an elastic body such as rubber and a resin member 100b made of resin. The resin member 100b is disposed so as to be in contact with the inner rotor 52, the outer rotor 51, and the center plate 73. The elastic member 100a disposed on the bottom side of the groove 71b with respect to the resin member 100b and the discharge pressure introduced into the groove 71b. It is configured to perform a sealing function when pressed by the brake fluid. The elastic member 100a and the resin member 100b press the outer rotor 51 in the upward direction in FIG. 2A with an elastic force to bring the outer rotor 51 and the inner rotor 52 into close contact with the side plate 72.

  By the seal member 100 arranged in this way, the high-pressure discharge port 61 and the low-pressure drive shaft are formed in the gap between the lower end surface in the axial direction of the inner rotor 52 and the outer rotor 51 and the first side plate portion 71. The gap between 54 and the inner rotor 52 and the suction port 60 can be sealed.

  Further, in order to seal the high pressure portion and the low pressure portion in the gap between the axial end surfaces of the inner rotor 52 and the outer rotor 51 and the first side plate portion 71, the seal member 100 is provided with the discharge port 61. And the drive shaft 54, and between the discharge port 61 and the suction port 60, and to reach the outer periphery of the outer rotor 51. On the other hand, in the present embodiment, in the seal member 100, the region from the seal member 80 through the drive shaft 54 and the discharge port 61 to the seal member 81 has a high-pressure portion and a low-pressure portion. It becomes an area | region required in order to seal a part. Therefore, on the axial end surface side, the portions where the confining portions 53a and 53b and the seal members 80 and 81 are present are the portions that are most required to be sealed, and in this portion, the resin member 100b is the side plate 72 and the outer rotor. 51, the inner rotor 52 is configured to come into strongest contact. In other words, the number of portions in contact with the inner rotor 52 and the outer rotor 51 in other areas where sealing is not required is negligibly small. Thus, the contact resistance is reduced by the seal member 100, and the mechanical loss between the first side plate 71 and the rotors 51 and 52 is reduced.

  On the other hand, as shown in FIG. 2B, of the outer rotor 51 and the inner rotor 52, the axial end faces 51b and 52b located on the upper side of the drawing are the end faces 51b and 52b that are the axes of the second side plate. It has a mechanical seal structure that slides in a state where it is pressed against the directional end surface 72b at a high pressure by the elastic force of the seal member 100 on the opposite side and seals the high pressure and the low pressure.

  The processing surfaces of the end faces 51b, 52b, 72b of the outer rotor 51, the inner rotor 52, and the second side plate 72 that perform this mechanical seal function are normal linear polishing streaks or circumferential shapes as shown in FIG. A radial polishing streak as shown in FIG. In this embodiment, the polishing bars in the second side plate 72, the outer rotor 51, and the inner rotor 52 are curved and curved radial bars extending from the axial center.

  The polishing streaks shown here are formed using a grindstone, and are obtained by rotating a grindstone having a circular polishing surface and simultaneously rotating the workpiece side. The curvature of the polishing bar is formed in accordance with the curvature of the outer periphery of the grindstone, and becomes smaller if the curvature of the grindstone is reduced.

  The polishing of the outer rotor 51 and the inner rotor 52 may be performed in an integrated state in which the outer rotor 51 and the inner rotor 52 are combined, or may be performed separately.

  Next, the operation of the brake device and the rotary pump 10 configured as described above will be described.

  The control valve 34 provided in the brake device is appropriately connected when a large braking force is required, for example, when a braking force corresponding to the brake depression force cannot be obtained or when the operation amount of the brake pedal 1 is large. The The high pressure master cylinder pressure generated by the depression of the brake pedal 1 through the pipe D is applied to the rotary pump 10.

  In the rotary pump 10, the inner rotor 52 rotates according to the rotation of the drive shaft 54 by driving the motor 11, and the outer rotor 51 also rotates in the same direction due to the meshing of the inner tooth portion 51 a and the outer tooth portion 52 a. To do. At this time, since the volume of each gap portion 53 changes in size while the outer rotor 51 and the inner rotor 52 make one rotation, the brake fluid is sucked from the suction port 60 and is directed from the discharge port 61 toward the pipeline A2. Exhale brake fluid.

  As described above, the rotary pump 10 performs the basic pumping operation of sucking the brake fluid from the suction port 60 and discharging the brake fluid from the discharge port 61 as the rotors 51 and 52 rotate. The wheel cylinder pressure is increased by the brake fluid discharged by the pump 10.

  In this pump operation, the suction port 60 side of the outer periphery of the outer rotor 51 is set to the suction pressure by the brake fluid sucked through the conduction path 73a, and the discharge port 61 side of the outer periphery of the outer rotor 51 is connected through the conduction paths 73b and 73c. The discharge pressure is set by the sucked brake fluid. For this reason, a low pressure portion and a high pressure portion are generated on the outer periphery of the outer rotor 51. Even in the gaps between the axial end surfaces of the inner rotor 52 and the outer rotor 51 and the first and second side plate portions 71, 72, the low-pressure discharge port 60 and the drive shaft 54 are connected to the inner rotor 52. The low pressure portion and the high pressure portion are generated by the gap and the high pressure discharge port 61.

  On the other hand, since the seal members 80 and 81 and the seal member 100 are provided, the outer periphery of the outer rotor 51 or the gap between the axial end surface of the outer rotor 51 and the inner rotor 52 and the first side plate 71 is provided. Through this, it is possible to prevent oil leakage from the high pressure side to the low pressure side. In FIG. 2, the seal member 100 does not seem to contact the outer rotor 51 and the inner rotor 52, but the seal member 100 bends as the discharge port 61 becomes high pressure, and is completely in contact with the outer rotor 51 and the inner rotor 52. Performs a sealing function.

  The axial end surfaces of the outer rotor 51 and the inner rotor 52 are directly pressed against the second side plate 72 to constitute a mechanical seal mechanism. For this reason, it is possible to prevent oil leakage from the high-pressure side to the low-pressure side through the gap between the axial end surfaces of the outer rotor 51 and the inner rotor 52 with the second side plate 2.

  In addition, due to the seal members 80 and 81, the suction port 60 side of the outer periphery of the outer rotor 51 becomes a low pressure, and the pressure is the same as that of the gap 53 communicating with the suction port 60. The discharge port 61 side has a high pressure, which is the same pressure as the gap portion 53 communicating with the discharge port 61. For this reason, the pressure balance inside and outside of the outer rotor 51 is maintained, and the pump can be driven stably.

  Furthermore, in the present embodiment, normal linear or circumferential polishing is performed on the finished surfaces of the end surfaces 51b, 52b, and 72b of the outer rotor 51, the inner rotor 52, and the second side plate 72 that perform the mechanical seal function. Radial polishing streaks are applied instead of streaks.

  As described above, the polishing streaks on the axial end surfaces of the inner rotor 52 and the outer rotor 51 are also made radial so that the gap 50a formed by the hole of the central plate 73 and the outer periphery of the outer rotor 51, the outer rotor 51, and the inner rotor 52 are formed. The gap 53 formed by the above is communicated by a minute groove formed by a polishing bar, and the gap 53 and the shaft hole 52b of the inner rotor 52 are also communicated by a minute groove. For this reason, oil is supplied and held on the sliding surfaces of the outer rotor 51 and the inner rotor 52 and the second side plate 72, and the loss torque can be reduced. In particular, since the pressure distribution of the rotary pump 10 is represented in FIG. 7, in the configuration of the rotary pump, a pressure difference is generated at both ends of the minute radial groove, and on the sliding surface. The presence effect of minute grooves communicating between the gaps is amplified.

  Furthermore, since the centrifugal force acts in the radial direction on the brake fluid existing in the minute groove portion of the polishing bar as the gear rotates, the direction of the centrifugal force and the direction of the minute groove can be determined by making the polishing bar radial. And oil is easily supplied to the sliding surface along the minute groove.

  As described above, by applying radial polishing bars to the end surfaces 51b, 52b, 72b of the outer rotor 51, the inner rotor 52, and the second side plate 72 that perform the mechanical seal function, oil is applied to the sliding surface. The supply can be promoted, and hence the friction coefficient of the sliding surface can be reduced, and the loss torque of the rotary pump 10 can be reduced.

(Second Embodiment)
FIG. 8A shows a front view of a rotary pump according to the second embodiment of the present invention, and FIG. 8B shows a cross-sectional view taken along line AA in FIG. 8A. In the first embodiment, radial polishing streaks are formed on the finished surfaces of the end surfaces in the axial direction of the outer rotor 51, the inner rotor 52, and the second side plate 72. On the other hand, in this embodiment, as indicated by an arrow in FIG. 8A, the normal linear polishing in the direction connecting the discharge port and the suction port with the finished surface of the axial end surface of the second side plate. In the second side plate, an oil groove 72c is provided at a position where the polishing bars of the outer rotor 51 and the inner rotor 52 extend along the polishing bars of the second side plate 72. The linear polishing bars are formed in a straight line over the entire surface of the outer rotor 51 and the inner rotor 52, and the second side plate 72 also includes a portion facing the outer rotor 51. It is formed in a straight line over the entire surface over a wider range.

  Of the portion facing the outer rotor in the second side plate 72, the portion where the oil groove 72C is provided is in a rotating state where the polishing bars of the outer rotor 52 and the polishing bars of the second side plate are in the same direction. The outer rotor 52 is opposed to the portion where the polishing bars remain in the outer rotor 52 in a straight line without being interrupted by the gap from the outer periphery. This portion is the portion where the loss torque is highest because the supply of oil from the gap portion is reduced. Therefore, when the oil groove 72C is provided so that the contact area between the outer rotor 51 and the second side plate 72 is reduced in the portion where the loss torque is highest as in the present embodiment, the contact friction resistance can be reduced. And loss torque can be reduced. The provision of the oil groove 72c not only reduces the contact area, but also provides an effect of reducing the loss torque by supplying the oil accumulated in the oil groove 72c to a nearby sliding surface.

  In this embodiment, the polishing streaks in the second side plate 72 are taken as an example in the horizontal direction of the paper in FIG. 8A. However, the polishing streaks in the second side plate 72 can be changed in the vertical direction of the paper. However, the site where the oil groove should be provided can be specified. That is, the portion of the second side plate that opposes the portion having the largest loss torque when the direction of the polishing streak in the portion where the loss torque is the largest in the outer rotor coincides with the direction of the polishing streak in the second side plate. Is a portion where an oil groove should be provided.

  Further, the oil groove may be provided on the outer rotor 51 side. In this case, regardless of the direction of the polishing bar in the second side plate, the portion where the polishing bar remains in a straight line without being interrupted by the gap from the outer periphery to the outer periphery in the outer rotor 51 produces the most loss torque. By the way, an oil groove may be provided at this portion.

(Third embodiment)
In the present embodiment, the finished surface of the end surface of the second side plate 72 is a radial polishing bar, and the finished surfaces of the end surfaces of the outer rotor 51 and the inner rotor 52 are circumferential polishing bars.

  In this case, the polishing bars of the second side plate 72 and the polishing bars of the outer rotor 51 and the inner rotor 52 intersect at substantially right angles in all regions during rotation. Therefore, when the polishing bars intersect, the actual contact area between the surface of the second side plate 72 and the surfaces of the outer rotor 51 and the inner rotor 52 becomes non-abnormally small due to the unevenness of the polishing bars. In this embodiment, the opposing surface of the outer rotor 51 is necessarily smaller than the contact resistance of the portion where the loss torque is provided with the oil groove 72C in the second embodiment. That is, the contact resistance of the present embodiment is equivalent to the case where the polishing bar direction of the second side plate 72 and the polishing bar direction of the rotated outer rotor 51 do not follow in the second embodiment. The contact resistance in the present embodiment is equivalent to the portion excluding the portion where the oil groove 72C is formed because the loss torque is the highest in the second embodiment, but the entire surface is equivalent when considering the resistance due to polishing. It has the merit that it can be contact resistance. In other words, when the resistance due to the polishing streak reaches the entire surface and the contact resistance is equivalent, there is no part where the contact resistance is large, that is, the part where the extra load is applied with rotation, and it is possible to suppress scraping of the contact surface due to friction. The performance degradation due to the expansion of the metal due to heat can be suppressed, which is advantageous in terms of pump performance.

  On the contrary, the finished surface of the end surface of the second side plate 72 is a circumferential polishing bar, and the finished surface of each end surface of the outer rotor 51 and the inner rotor 52 is a radial polishing bar. The same effect as described above can be obtained.

(Fourth embodiment)
About each said embodiment, an oil groove is provided in the site | part (site | part equivalent to the wide parts 100C and 100D of the sealing member 100) which opposes the closure parts 53a and 53b among the axial direction end surfaces 72b of the 2nd side plate 72. You may make it provide. In this portion, the seal member 100 is directly in contact with the outer rotor 51 and the inner rotor 52 for sealing, and sliding on the second side plate 72 side becomes severe. For this reason, by installing an oil groove, lubrication can be assisted and loss torque can be reduced.

  Further, the rotation is not limited to the above-described embodiments, and the polishing bars on the axial end surfaces 51b and 52b of the outer rotor 51 and the inner rotor 52 and the axial end surface 72b of the second side plate 72 are linear or circumferential. If the oil groove as in the present embodiment is also provided for the pump 10, it is possible to obtain an effect of reducing the loss torque.

Further, in the first embodiment, the polishing bars formed on the axial end surfaces of the second side plate 72, the outer rotor 51, and the inner rotor 52 have a curved shape . ), And may be a radial shape extending straight from the axial center position. In this case, the same effect as the effect by the centrifugal force in the first embodiment can be exhibited.

Further, as shown in FIGS. 10A and 10B , the axial end face of one of the second side plate 72, the outer rotor 51, and the inner rotor 52 is a curved radial polishing streak, and the other is used. It is also possible to use a linear radial polishing bar. Also in this case, the same effect as that of the first embodiment can be obtained. Further, in addition to the effects of the first embodiment, the polishing bars of the second side plate 72 and the polishing bars of the outer rotor 51 and the inner rotor 52 do not overlap each other and always intersect with each other. The contact area is reduced by the unevenness of the polishing streaks, and the contact resistance and loss torque are reduced. Further, as shown in FIG. 11 , the curvature of the curved surface of the radial polishing bar of the curved surface of the sliding surface of the second side plate 72 and that of the curved surface of the sliding surface of the outer rotor 51 and the inner rotor 52 are curved. The same effect can be obtained even when facing in the opposite direction. In addition, the solid line in FIG. 11 shows the polishing streaks in the outer rotor 51 and the inner rotor 52, and the dotted line shows the polishing streaks in the second side plate. Further, as shown in FIG. 12 , both the radial radial reinforcing bars on the sliding surface of the second side plate 72 and the radial radial reinforcing bars on the sliding surfaces of the outer rotor 51 and the inner rotor 52 are radial. A similar effect can be obtained by shifting the center positions of the polishing bars so that they do not overlap. In addition, the solid line in FIG. 12 shows the polishing streaks in the outer rotor 51 and the inner rotor 52, and the dotted line shows the polishing streaks in the second side plate.

  In the above-described embodiment, the oil groove 72c is formed at the position shown in FIG. 8A in view of the linear polishing streaks applied to the second side plate 72. The oil groove 72c may be formed simply for the purpose of reducing the contact area on the mechanical seal surface between the axial end surface of the outer rotor 51 and the second side plate 72 as described below.

  That is, in the second side plate 72, the oil groove 72c is provided in a portion of the second side plate 72 facing a portion that does not interfere with the internal tooth portion 51a on the axial end surface of the outer rotor 51. At this time, the high pressure portion and the low pressure portion exist in the pressure distribution related to the outer circumference of the outer rotor shown in FIG. 7, but the oil groove 72c is formed so as not to straddle the high pressure portion and the low pressure portion. That is, the pressure difference is prevented from being eliminated through the oil groove 72c.

  Note that the oil groove 72c is preferably provided on the second side plate 72 side at a portion in contact with the high pressure portion of the outer circumference of the outer rotor in FIG. That is, even if the low-pressure part side is sealed with the sealing members 100, 80, 81, 100% complete sealing cannot be achieved, and the oil flows from the high-pressure part side to the low-pressure part side. This is because there is a possibility that the seal portion is lubricated, but the flow of oil to the mechanical seal portion due to a pressure difference cannot be expected in the high pressure portion. When the oil groove 72c is provided corresponding to the high-pressure portion of the outer circumference of the outer rotor in this way, the oil groove 72c may be provided in a range that coincides with the portion of the high-pressure portion of the gap portion in the radial direction. The outer circumferential portion of the outer rotor that is the low pressure portion and in the same radial direction may be provided within the range of the high pressure portion. When the oil groove 72c is provided as in the former, the contact area is reduced by the area of the oil groove 72c at the portion where the rate of lubrication due to the pressure difference is the smallest in the mechanical seal portion. Therefore, the frictional resistance can be reduced by the reduced contact area. In addition, when the oil groove 72c is provided as in the latter case, not only the contact area corresponding to the oil groove 72c is reduced, but also the oil groove 72c accumulates in a portion where the lubrication is most performed in the mechanical seal portion by the differential pressure action. With oil, the flow of oil can be further increased, and overall lubrication can be enhanced.

  In the embodiments described above, the first confinement portion (53a) is defined as having the maximum volume among the plurality of gap portions, but may not strictly be the maximum due to the design of the pump. is there. Similarly, the second confinement part (53b) stipulates that the volume of the plurality of gaps is the smallest, but it may not be strictly the smallest due to the design of the pump. However, in the present invention, there are at least two gap portions for dividing the plurality of gap portions into the suction side and the discharge side, and the closed portion in the vicinity where the volume is maximized is defined as the first closed portion and the volume. The confinement portion in the vicinity where the value is minimum is defined as the second confinement portion.

It is a pipe line lineblock diagram of a brake equipment provided with a rotary pump in a 1st embodiment. It is a figure which shows the specific structure of the rotary pump 10 in FIG. It is a schematic diagram of the sealing member 100 shown in FIG. It is the figure which showed the linear grinding | polishing streak. It is a figure which shows the grinding | polishing line | wire provided on the axial direction end surface of the outer rotor 51 of the rotary pump 10 in FIG. 1, the inner rotor 52, and the 2nd side plate 72. FIG. It is the figure which expanded the sliding surface of the outer rotor 51 and the inner rotor 52, and the 2nd side plate 72. FIG. It is the figure which showed the pressure distribution of the rotary pump 10 in FIG. It is a figure which shows the specific structure of the rotary pump 10 in 2nd Embodiment of this invention.   It is the schematic of the grinding | polishing reinforcement | strengthening given to the outer rotor, inner rotor, and 2nd side plate in other embodiment.   It is the schematic of the grinding | polishing reinforcement | strengthening given to the outer rotor, inner rotor, and 2nd side plate in other embodiment.     It is the schematic of the grinding | polishing reinforcement | strengthening given to the outer rotor, inner rotor, and 2nd side plate in other embodiment.   It is the schematic of the grinding | polishing reinforcement | strengthening given to the outer rotor, inner rotor, and 2nd side plate in other embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 50 ... Casing , 51 ... Outer rotor, 51a ... Inner tooth part, 52 ... Inner rotor, 52a ... Outer tooth part, 53 ... Space | gap part, 53a, 53b ... Close-up part, 54 ... Drive shaft, 60 ... Inlet port, 61 ... discharge port, 71, 72 ... first and second side plates, 72c ... oil groove, 80 ... sealing member (sealing means) .

Claims (3)

An outer rotor having an inner tooth portion (51a) on the inner periphery, and an inner rotor (52) having an outer tooth portion (52a) on the outer periphery and rotating about the drive shaft (54). A rotating part in which a plurality of gaps (53) are formed between meshing with the external tooth part,
A first side plate (71) disposed on one axial end surface side of the rotating portion; and an axial end surface of the outer rotor and the inner rotor disposed on the other axial end surface side of the rotating portion. A second side plate (72) whose contact surface mechanically seals, and a casing (50) formed to cover the rotating part;
A suction port (60) provided in the casing for sucking fluid into the rotating part; and a discharge port (61) for discharging fluid from the rotating part;
Sealing means for dividing a space in which the rotating part inside the casing is enclosed into a low-pressure side space connected to the suction port and a high-pressure side space connected to the discharge port; An oil groove provided in a portion that does not overlap the internal tooth portion of the portion of the second side plate that faces the axial end surface, and that extends across the high-pressure side space and does not straddle the low-pressure side space ( 72c)
A rotary pump comprising: The high-pressure side space and the low-pressure side space are provided in both the plurality of gap portions and the portion between the outer circumference of the outer rotor and the casing, The oil groove is formed in a range where a space portion and a space portion on the high pressure side between the outer circumference of the outer rotor and the casing overlap in the radial direction of the rotating portion. The rotary pump according to claim 1. Brake fluid pressure generating means (1-3) for generating brake fluid pressure based on the pedal effort;
Braking force generating means (4, 5) for generating a braking force on the wheel based on the brake fluid pressure;
A main line (A) connected to the brake fluid pressure generating means and transmitting the brake fluid pressure to the braking force generating means;
In the brake device having an auxiliary line (D) connected to the brake fluid pressure generating unit and supplying brake fluid to the main line side in order to increase the braking force generated by the braking force generating unit,
The rotary pump according to claim 1 or 2 , wherein the suction port can suck the brake fluid on the brake fluid pressure generating means side through the auxiliary conduit, and the discharge port is connected to the braking force generating means through the main conduit. A brake device comprising a rotary pump, wherein the brake device is arranged so that the brake fluid can be discharged toward the vehicle.

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