JP4804491B2 - Brake device - Google Patents

Description

  The present invention relates to a brake device capable of executing anti-lock control during braking (hereinafter referred to as ABS control) and stable control for controlling traction and vehicle yaw rate by braking force, and in particular, has a pump driven by a motor. The present invention relates to a brake device.

Conventionally, a brake device capable of executing ABS control and stability control has a hydraulic pressure control valve capable of reducing, maintaining, and increasing the wheel cylinder pressure, and brake fluid drained to a reservoir when the hydraulic pressure control valve is depressurized. A pump is known that includes a pump that sucks and discharges upstream of a hydraulic control valve, a damper that reduces discharge pulsation of the pump, and a motor that drives the pump. As such a brake device, the thing of patent document 1 is known, for example. In this conventional brake device, a plunger constituting a pump is slidably accommodated in a housing in a direction orthogonal to the rotation axis of the motor, and a damper and a reservoir are provided in the housing. A motor is attached to one side of the housing. The motor mounting structure is such that a fixing bolt is provided in a direction parallel to the rotation axis of the motor and orthogonal to the axial direction of the plunger, and the fixing bolt is formed in a fastening screw hole opened on the side of the housing. In contrast, the structure is fastened.
JP-A-2-231253

By the way, when the pump is driven by rotating the motor, the reaction force of the hydraulic pressure is received in the pump shaft direction during the compression stroke of the pump plunger, and further, this reaction force is perpendicular to the rotation shaft of the motor from the plunger. As a result, the rotating shaft vibrates, and noise and vibration are generated in the apparatus. In this case, as the fixing point for fixing the motor to the housing moves away from the axis of the pump in the direction orthogonal to the axis, the support rigidity of the motor becomes lower, which is disadvantageous for noise and vibration. Therefore , providing the motor fixing point on the plunger axis increases the motor support rigidity and is advantageous for noise and vibration. However, the housing accommodates the screw hole for fastening the fixing bolt and the plunger. The holes are aligned in the axial direction of the motor rotation shaft, and it is necessary to have a dimension that allows a screw hole to be provided between the side surface of the housing and the hole that accommodates the plunger. .
In addition, when dampers and reservoirs are provided in the housing, the closer the components are, the smaller the overall volume of the housing can be reduced. There is a problem that it is difficult to secure a necessary volume in the reservoir and to provide a screw hole for fastening the fixing bolt at an optimal position.
The present invention has been made paying attention to the above-mentioned conventional problems, and the first is to arrange the fixing point by the fixing bolt of the motor at the optimum position for noise and vibration and to reduce the size of the housing. The second object is to secure the necessary volume of the damper and the reservoir and to provide the motor fixing point at the optimum position while reducing the size of the housing.

  In order to achieve the first object described above, the present invention provides two screw holes formed in a housing substantially in parallel with a motor rotation shaft and opened at an end surface of the housing, and fastened to the screw holes to mount the motor. A fixing bolt for fixing to the end face of the housing, and the projection of the two screw holes in the axial direction of the screw hole overlaps or is close to the pump hole as long as it does not overlap with the axis of the pump hole. Then, the axial center of the pump hole is sandwiched, and the depth of the screw hole in the axial direction reaches the pump hole as viewed from the axial direction of the pump hole.

  When the motor is rotated, the plunger reciprocates in the direction orthogonal to the motor rotation axis, sucking in the brake fluid and discharging it to the brake circuit. At this time, a hydraulic reaction force acts on the plunger, and this reaction force is input in a direction orthogonal to the motor rotation shaft. The reaction force input to the motor rotation shaft is supported by a fixing bolt. At this time, since the fixing bolt and the screw hole are arranged at a position overlapping or close to the pump hole in the projection direction, higher support rigidity can be obtained compared to the case where the fixing bolt and the screw hole are provided away from the pump hole. In addition, since the screw hole is arranged at a position that does not overlap with the axis of the pump hole in the projection direction, the wall thickness from the end face of the housing to the pump hole is smaller than when the screw hole is overlaid on the axis of the pump hole. The thickness can be reduced, and the size of the housing can be reduced accordingly.

  Hereinafter, embodiments of the present invention will be described based on examples shown in the drawings.

  1 to 5 show the brake device of the first embodiment. FIG. 1 is a front view of the brake unit, FIG. 2 is a side view of the brake unit, FIG. 3 is a plan view of the brake unit, and FIG. Sectional drawing (S4-S4 sectional drawing of FIG. 2) and FIG. 5 are circuit diagrams of a brake device.

  First, the overall configuration of the brake device will be briefly described with reference to FIG. 5. This brake device is configured to be able to execute ABS control. In FIG. It is a master cylinder as a fluid pressure generating means for generating fluid pressure. The master cylinder 1 has wheel cylinders 4 and 4 as braking operation parts by a brake circuit 3 (only two wheel cylinders are shown in the figure, and the other two wheel wheel cylinders 4 and 4 connected to the brake circuit 3). Are not shown). In the middle of the brake circuit 3, a hydraulic pressure control valve 5 capable of reducing, maintaining and increasing the brake hydraulic pressure of the wheel cylinder 4 is provided. The hydraulic pressure control valve 5 is connected to a drain circuit 7 that discharges brake fluid to the reservoir 6 when the pressure is reduced. The reservoir 6 is connected to the suction circuit 9 of the pump 8, and the discharge circuit 10 of the pump 8 is located on the master cylinder side (this is called upstream) of the hydraulic control valve 5 of the brake circuit 3. When the pump 8 is driven by being connected to the position and rotating the motor 11, the brake fluid in the reservoir 6 is returned to the brake circuit 3. The discharge circuit 10 is provided with a damper 12 that absorbs the discharge pulsation of the pump 8. The suction circuit 9 and the discharge circuit 10 are provided with a backflow prevention suction valve 9a and a discharge valve 10a, respectively.

  Further, a normally open gate valve 13 that is closed during ABS control is provided upstream of the connection point of the discharge circuit 10 in the brake circuit 3. In the embodiment, the master cylinder 1 is shown as the hydraulic pressure generating means. However, the hydraulic pressure generating means is a means for generating the brake hydraulic pressure in response to the driver's braking operation. It may be a means for detecting and forming the hydraulic pressure of the hydraulic pressure source by electrical control based on the detected value.

  Among the configurations shown in FIG. 5 described above, the configuration surrounded by the alternate long and short dash line A1 is included in the brake unit of the brake device to which the present invention shown in FIGS. 1-4, 21 is a housing in the figure. Inside the housing 21, two pump holes 22 and 22 having one end opened on the side surfaces 21b and 21b of the housing 21 are formed on the same axis (see FIG. 4). In the figure, reference numeral 22a denotes a pump shaft that is the axis of the pump hole. Further, a cylinder 23 and a cap 24 are sequentially inserted into each pump hole 22, and a nut 25 is fastened to the opening end of the pump hole 22 to fix the cap 24 and the cylinder 23.

  Plungers 26 are accommodated in the cylinders 23, and the plungers 26 are urged by springs 27 in a direction protruding from the cylinders 23, and the tip portions of the plungers 26 are in contact with the cam surfaces 28. Therefore, when the cam surface 28 rotates, each plunger 26 reciprocates on the line of the pump shaft 22a, and the brake fluid is sucked into the pressure chamber 29, compressed and discharged.

The cam surface 28 is formed on the outer periphery of a motor rotating shaft 30 that is a rotating shaft of the motor 11. That is, the motor rotary shaft 30 is inserted into the two drive holes 31 drilled in the housing 2 1 in a direction perpendicular to the pump bore 22 at a location between the pump bore 22. In the figure, reference numeral 30a denotes a rotation axis that is the axis of the motor rotation axis.

  The base 11 of the cover 11a of the motor 11 has flanges 11b and 11b formed at two points symmetrical with respect to the rotational axis, and fixing bolts 32 are inserted into the flanges 11b. The fixing bolt 32 opens to one side surface of the housing 21 (hereinafter, this surface is referred to as a front surface 21a) and is fastened to a screw hole 33 formed in the housing 21 so that the motor 11 is fixed to the front surface 21a of the housing 21. Has been.

  The screw hole 33 is substantially parallel to the rotation axis 30a and is provided at a position very close to the pump hole 22 although it does not overlap the pump hole 22 when projected in the axial direction. As shown in FIG. 1, both fixing bolts 32 and both screw holes 33 are arranged at point-symmetric positions around the rotation axis 30a, and a line a connecting the screw hole axes 33a is It is provided on a line inclined by 20 ° with respect to the pump shaft 22a (θ = 20 °). Further, as shown in FIG. 2, the depth of the screw hole 33 is formed to reach the pump hole 22 if the screw hole 33 is provided on the pump shaft 22a line.

  In the figure, 34 and 34 are mount insulators for attaching the housing 21 to the vehicle body when the vehicle is mounted on the vehicle.

  Next, the operation of the first embodiment will be described. When the motor 11 is driven and the motor rotating shaft 30 is rotated, the plungers 26 and 26 are reciprocated by the cam surface 28 to suck and discharge the brake fluid. At this time, hydraulic reaction forces F1 and F2 (see FIG. 4) act on the plungers 26 and 26 in the axial direction. It is transmitted in the orthogonal direction. The reaction forces F1 and F2 input to the motor rotating shaft 30 are finally supported by fixing bolts 32 and 32.

  At this time, in the first embodiment, the fixing bolt 32 and the screw hole 33 are arranged at symmetrical positions with the rotation axis 30a as the center, and the axis 33a is inclined only by 20 ° with respect to the pump shaft 22a. Since the screw holes 33 are projected and arranged so as to be close to the pump holes 22, high support rigidity can be obtained. That is, as the fixing point by the fixing bolt 32 and the screw hole 33 is further away from the pump shaft 22a, the moment due to the reaction forces F1 and F2 acting on the plunger 26 increases, and the fixing point becomes the rotational axis 30a. If they are not symmetrically arranged, the moment that the input to the motor rotating shaft 30 acts on the fixed point increases.

  Further, in the first embodiment, as described above, the screw hole 33 is arranged close to the pump hole 22 at the projection position so as to increase the support rigidity so as not to overlap the pump shaft 22a and the pump hole 22 at the projection position. Therefore, the thickness of the housing 21 can be reduced (the size of the portion B in FIG. 2 is reduced) compared to the case where the screw hole 33 is disposed so as to overlap the pump shaft 22a, and the housing 21 is formed more compact accordingly. be able to. That is, when the screw hole 33 is arranged so as to overlap the pump shaft 22a, the screw hole 33 penetrates the pump hole 22 if the thickness of the housing 21 is the same as that of the first embodiment. It is necessary to move away from the front surface 21a of the housing 21 (increase the dimension B in FIG. 2), and the thickness of the housing 21 increases accordingly, and the housing 21 increases in size.

  As described above, in the first embodiment, the overall configuration is ensured by ensuring the support rigidity of the motor 11 against the reaction forces F1 and F2 of the hydraulic pressure acting on the plunger 26 and reducing the thickness of the housing 21. The effect that it is possible to achieve both compactness is obtained.

  Next, the brake device of Example 2 will be described. In the description of the second embodiment, the same components as those of the first embodiment are denoted by the same reference numerals as those of the first embodiment, and the description thereof is omitted.

  In the second embodiment, the configuration of the portion surrounded by the alternate long and short dash line A2 in the configuration shown in FIG. 5 is provided in the brake unit shown in FIGS. A damper 12 is added. That is, in the housing 21 of the second embodiment, a first reservoir 61 and a first damper 121, and a second reservoir 62 and a second damper 122 are respectively provided to two plungers 26 (not shown in FIGS. 6 to 9). (It is to be noted that two reservoirs and two dampers are provided, so that the reference numerals are changed from those in FIG. 5). Both dampers 121, 122 and both reservoirs 61, 62 are configured by opening damper holes 121a, 122a and reservoir holes (not shown) in the bottom surface 21c of the housing 21, respectively, and as shown in FIG. The thickness of the housing 21 is reduced by disposing the line 12a connecting the axes of the dampers 121 and 122 and the line 6b connecting the axes of the reservoirs 61 and 62 in the direction of the rotation axis 30a of the motor 11. The dimension in the direction of the rotation axis 30a is reduced. In the second embodiment, the positions where the screw holes 33 and the fixing bolts 32 are provided are the same as those in the first embodiment.

  Incidentally, in the second embodiment, the shapes of the damper holes 121a and 122a of the first damper 121 and the second damper 122 are different. That is, the opening ends of both damper holes 121a and 122a are formed to have the same diameter. Therefore, when the required volume is secured in the shape in which both holes 121a and 122a have the same diameter over the entire length, the dimension in the axial direction of the damper hole 121a of the first damper 121 is obtained. However, when the damper hole 122 a of the second damper 122 is formed in the same shape as that of the first damper 121, the screw hole 33 arranged on the right side in FIG. 6, that is, between the pump shaft 22 a and the second damper 122. The space for forming the screw hole 33 disposed between them is lost. Therefore, the second damper 122 forms the damper hole 122a to the full length that does not reach the screw hole 33, and as shown in FIGS. 6, 8, and 9 (cross-sectional view of S9-S9 in FIG. 7), the damper hole 122a is formed. Two enlarged portions 122 b are provided on the side surface of the first damper 121, and the entire volume is the same as the damper hole 121 a of the first damper 121.

  Since the second embodiment is configured as described above, the following effects can be obtained in addition to the effects of the first embodiment. In the second embodiment, the screw hole 33 for fastening the fixing bolt 32 for fixing the cover 11a of the motor 11 is disposed at a point-symmetrical position about the rotation axis 30a, and the hydraulic pressure is applied to the motor rotation shaft 30 from the plunger 26. In order to obtain a high support rigidity when the reaction force is input, a space in which the screw hole 33 can be formed between the pump hole 22 and the second damper 122 of the housing 21 is ensured. In this case, while keeping the entire length of the damper hole 122a of the second damper 122 short, the enlarged portion 122b was provided in the radial direction of the damper hole 122a, and the same volume as the first damper 121 having a long total length could be secured. Therefore, it is possible to obtain a desired damper performance while reducing the vertical dimension of the housing 21 in FIG.

  In the second embodiment, the positions of the lines 6b and 12a connecting the axial centers of the reservoirs 61 and 62 and the dampers 121 and 122 are shifted from the same line. The effect that the dimension in the direction of the core 30a can be reduced to be compact can be obtained.

[Effect of Example]
As described above, the brake device according to the first embodiment is arranged at a position that overlaps or is close to the pump hole as long as the screw hole is projected in the axial direction so as not to overlap the axial center of the pump hole. Since it is configured, it supports the reaction force of the hydraulic pressure acting on the plunger to be transmitted to the motor with high rigidity, reduces the thickness from the end surface of the housing to the pump hole, and reduces the size of the housing, There is an effect that it is possible to achieve both miniaturization of the apparatus.
In addition, since the fixing bolt and the screw hole are provided at a point-symmetrical position about the axis of the motor rotation shaft, when the reaction force of the hydraulic pressure is input to the motor rotation shaft in the direction perpendicular to the axis, There is an effect that a moment is hardly generated at a fixed point of the motor and higher support rigidity can be obtained.
In addition, since the line connecting the axis of the fixing bolt and screw hole and the axis of the pump hole is arranged at an angle of 20 °, the moment at the motor fixing point is the same as above. Is less likely to occur and high support rigidity is obtained.
In the second embodiment, one of the two screw holes is formed at a position between the pump hole and the second damper hole, and in order to secure a space for forming the screw hole, the axial dimension of the second damper hole is determined. While securing the damper performance by reducing the length of the housing, the second damper hole is provided with an enlarged portion in the radial direction so as to have substantially the same volume as the first damper hole. Therefore, the apparatus can be reduced in size without deteriorating the damper performance.

It is a front view which shows the brake unit of the brake device of Example 1. FIG. It is a side view of the brake unit. It is a top view of the brake unit. It is S4-S4 sectional drawing of FIG. 1 is an overall view of a brake device according to an embodiment. It is a front view which shows the brake unit of the brake device of Example 2. FIG. It is a side view of the brake unit. It is a bottom view of the brake unit. It is S9-S9 sectional drawing of FIG.

Explanation of symbols

1 Master cylinder (hydraulic pressure generating means)
2 Brake pedal 3 Brake circuit 4 Wheel cylinder (braking actuator)
5 Fluid pressure control valve 6 Reservoir 6a Reservoir hole 6b Line 7 connecting the shaft center Drain circuit 8 Pump 9 Suction circuit 9a Suction valve 10 Discharging circuit 10a Discharge valve 11 Motor 11a Cover 11b Flange portion 12 Damper 12a Line 13 connecting the shaft center Valve 21 Housing 22 Pump hole 22a Pump shaft 23 Cylinder 24 Cap 25 Nut 26 Plunger 27 Spring 28 Cam surface 29 Pressure chamber 30 Motor rotating shaft 30a Rotating shaft 31 Driving hole 32 Fixing bolt 33 Screw hole 33a Screw hole shaft center 34 Mount insulator 61 First reservoir 62 Second reservoir 121 First damper 121a Damper hole 122 Second damper 122a Damper hole 122b Enlarged portion

Claims (13)

A braking actuator that generates braking force by brake fluid pressure at the wheel;
A brake circuit formed in the housing and connected to the braking actuator;
A pump provided in the housing for supplying hydraulic pressure to the brake circuit;
A hydraulic control valve capable of controlling a brake hydraulic pressure supplied to the braking operation unit;
A volume chamber provided on the brake circuit;
A motor for driving the pump;
A motor rotating shaft inserted into the housing and having a cam surface formed on the outer periphery;
Accommodating the contacting plunger with the cam surface, a pump hole formed in said motor shaft and straight intersects axis on in the housing,
Is formed on the motor rotation shaft and a flat row in the housing, and two screw holes opened to the end surface of the housing,
A fixing bolt fastened to the screw hole and fixing the motor to an end face of the housing;
The projection of the two screw holes in the axial direction of the screw hole overlaps or is close to the pump hole as long as it does not overlap the volume chamber and does not overlap the axis of the pump hole. brake and wherein the and Nde squeezing the axis. 2. The brake device according to claim 1, wherein the volume chamber is formed on an axis extending in a direction perpendicular to the axis of the pump hole and the motor rotation axis in the housing . The volume chamber is a reservoir that is connected to the suction side of the pump and stores brake fluid discharged from the braking operation unit, or a damper that is connected to the discharge side of the pump and absorbs discharge pulsation of the pump. The brake device according to claim 1 or 2, wherein The brake device according to any one of claims 1 to 3, wherein a depth of the screw hole in the axial direction reaches the pump hole as viewed from an axial direction of the pump hole . The brake device according to any one of claims 1 to 3 , wherein the screw hole is formed to a depth overlapping with the pump hole in an axial direction of the screw hole . The brake device according to any one of claims 1 to 5, wherein a depth in the axial direction of the screw hole reaches the volume chamber when viewed from an axial direction of the pump hole . The volume chamber, Ri damper der to absorb discharge pulsation of the pump is connected to the discharge side of the pump,
Two each of the plunger and the pump hole are provided,
A first damper hole corresponding to the first plunger and a second damper hole corresponding to the second plunger are arranged so that the axes of both the damper holes are orthogonal to the axis of the pump hole and the motor rotation axis. In the same surface of the housing,
When viewed from the axial direction of the screw hole, one of the two screw holes is disposed on the opposite side of the first damper hole across the pump hole, and the other screw hole is connected to the pump hole and the second hole. Place between the damper hole and
Forming the same opening diameter dimension of both damper holes, forming the axial dimension of the second damper hole shorter than the axial dimension of the first damper hole,
The brake device according to claim 6, wherein an enlarged portion that expands the volume in the radial direction is provided on a side surface of the second damper hole, and both the damper holes are formed in the same volume . The brake device according to any one of claims 1 to 7 , wherein an axial center of the pump hole is shifted to the motor side with respect to a center position of the housing in the motor rotation axis direction . In the end surface of the housing where the screw hole is opened, the two screw holes are provided at point-symmetric positions around the motor rotation axis,
The brake device according to any one of claims 1 to 8 , wherein a line connecting the shaft centers of the two screw holes has a predetermined angle with respect to the shaft center of the pump hole . The brake device according to claim 9 , wherein the predetermined angle is 20 ° or less . The volume chamber is a reservoir that is connected to the suction side of the pump and stores brake fluid discharged from the braking operation unit, and a damper that is connected to the discharge side of the pump and absorbs discharge pulsation of the pump. ,
A reservoir hole and a damper hole are provided that open in a plane perpendicular to the end surface of the housing to which the motor is fixed and parallel to the axis of the pump hole,
The reservoir hole and the damper hole axis are provided in a direction perpendicular to the pump hole axis and the motor rotation axis,
And axis of the damper hole to the axis of the reservoir hole, according to any one of claims 1 to 10, characterized in that is arranged offset in the motor rotation axis direction and the axial direction of the pump hole Brake device. A brake circuit formed in the housing and connected to a wheel cylinder provided on the wheel;
A pump provided in the housing for supplying hydraulic pressure to the brake circuit;
A hydraulic control valve capable of controlling the brake hydraulic pressure supplied to the wheel cylinder;
A volume chamber provided on the brake circuit;
A motor for driving the pump;
A motor rotating shaft inserted into the housing and having a cam surface formed on the outer periphery;
A pump hole that houses a plunger that contacts the cam surface and is formed on an axis perpendicular to the motor rotation axis in the housing;
Two screw holes formed in the housing in parallel to the motor rotation shaft and open to an end surface of the housing;
A fixing bolt fastened to the screw hole and fixing the motor to an end face of the housing;
The projection of the two screw holes in the axial direction of the screw hole overlaps or is close to the pump hole as long as it does not overlap the volume chamber and does not overlap the axis of the pump hole. features and be Lube rake device that across the axis. Hydraulic pressure generating means for generating brake hydraulic pressure by the driver's braking operation;
A brake actuating part connected to the hydraulic pressure generating means via a brake circuit to generate a braking force at the wheel;
Hydraulic pressure control means provided in the middle of the brake circuit and capable of reducing, maintaining and increasing the brake hydraulic pressure in the braking operation unit;
A pump that sucks in brake fluid discharged at the time of pressure reduction by the hydraulic pressure control means and discharges it to the hydraulic pressure generation means side of the hydraulic pressure control means of the brake circuit;
A motor that is a drive source of the pump;
A motor rotation shaft inserted into a drive hole formed in the housing and having a cam surface formed on the outer periphery;
A volume chamber provided in the housing in the middle of the brake circuit,
The pump has a pump hole symmetrically arranged on the same axis perpendicular to the motor rotation axis with a cam surface interposed therebetween, and a tip of the pump abutting on the cam surface to be accommodated in the pump hole and rotating the motor rotation shaft. And a plunger that reciprocates along with,
In the brake device in which the motor is fixed to the end surface of the housing by fastening a fixing bolt to two screw holes formed in the housing in parallel with the motor rotation shaft,
The two screw holes are disposed on different sides across the axis of the pump hole as viewed from the axial direction of the screw hole,
The features and be Lube rake device that axial projection is in or proximate overlaps the pump bore in a range that does not overlap with the axial center of the overlap is not and the pump bore and the volume chamber of each screw hole.

Images