JP3745084B2 - Disc brake device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a disc brake device used in a railway vehicle or the like, and more particularly, to an improvement in an adjuster mechanism for a control device.
[0002]
[Prior art]
In a railway vehicle or the like, for example, a disc brake device as shown in FIG. 2 is provided for each wheel to brake the vehicle.
[0003]
As shown in the figure, the brake caliper 1 of the disc brake device is slidably attached via brackets 1A and 1B to a mounting portion 8 fixed on the vehicle body side via a support pin 9. The support pin 9 is disposed in parallel with the brake disc 3 of the disc brake device, and the brake caliper 1 is movable along the support pin 9.
[0004]
On the other hand, the pair of arms 2A, 2B of the brake caliper 1 are provided with braker support portions 4A, 4B at the tips, and these braker support portions 4A, 4B are provided on both side surfaces of the brake disc 3 that rotates integrally with each vehicle wheel. 4B wraps around. The control members 4A and 4B support the control devices 5A and 5B, respectively. These control devices 5A and 5B sandwich the side surface of the brake disc 3 from both sides, and each have a planar friction surface. The friction surface is made substantially parallel to both sides of the brake disk 3.
[0005]
Further, as shown in FIG. 3 which is a partial cross-sectional view perpendicular to the paper surface of FIG. 2, a pair of pistons 10 is incorporated in parallel in one of the restrictor support portions 4A, and the restrictor 5A includes these pistons 10 It is supported at the tip via a support member 11.
[0006]
These pistons 10 are supplied with hydraulic pressure through a hydraulic pressure introduction port 7 disposed on the arm 2A on the same side and extend toward the brake disc 3 to press the brake member 5A against the brake disc 3 side. In this case, since the brake caliper 1 can move along the support pin 9, the brake members 5A and 5B eventually sandwich the brake disk 3 from both sides, and the brake disk 3 is caused by the friction force generated at this time. Is braked.
[0007]
Further, the adjuster support portion 4A is provided with an adjusting mechanism 13 as shown in FIG.
[0008]
As shown in the figure, the adjuster piston 14 of the adjuster mechanism 13 is slidably accommodated in a sleeve 15 fixed to the frame 12 of the restrictor support portion 4A, and is supported by being locked to the flange portion 14A at the tip. The member 11 is supported.
[0009]
A hole 14B extending from the base end side is formed on the center axis of the adjuster piston 14, and an adjuster pin 16 is inserted into the hole 14B. Further, the friction spring 17 is press-fitted between the adjuster piston 14 and the adjuster pin 16 on the base end side where the diameter of the hole 14B is expanded. Thus, in the normal state, the adjuster piston 14 and the adjuster pin 16 are integrally held by the frictional force of the friction spring 17 so as not to move relative to each other. The washer 18 of the friction spring 17 is locked by a ring spiral 19 and is integrated with the adjuster pin 16.
[0010]
Further, a receiving member 20 that is movable with respect to the frame 12 is provided on the base end side of the adjuster piston 14, and the adjuster pin 16 is fixed to the receiving member 20. A predetermined interval (an interval substantially equal to the total amount of movement of the control members 5A and 5B during braking) is provided between the receiving member 20 and the end portion of the sleeve 15, and the adjuster piston 14 is supported by the support member 11 during braking. At the same time, when it moves to the brake disc 3 side, the receiving member 20 comes into contact with the end of the sleeve 15. A return spring 21 is provided between the receiving member 20 and the flange portion 15A on the outer periphery of the sleeve 15, and after braking, the return spring 21 pulls the adjuster piston 14 and the support member 11 back to predetermined positions. Yes.
[0011]
By the way, the friction surfaces of the restrictors 5A and 5B are worn by friction with the brake disc 3, but in this adjusting mechanism 13, the position of the restrictor 5A is moved to the brake disc 3 side, and the restrictor 5A and the brake disc 3 are moved. The responsiveness of the brake operation is kept constant by keeping the interval of the constant.
[0012]
This action will be described in more detail. When the friction surfaces of the control members 5A and 5B are worn down, the adjuster piston 14 is integrated with the adjuster pin 16 until the receiving member 20 and the end of the sleeve 15 come into contact with each other during braking. Even when moved, the brake members 5A and 5B do not contact the brake disc 3. In this case, the receiving member 20 in contact with the sleeve 15 and the adjuster pin 16 integral with the receiving member 20 cannot move any further. However, since the piston 10 further pushes out the support member 11 until the control member 5A comes into contact with the brake disc 3, the adjuster piston 14 integrated with the support member 11 overcomes the frictional force of the friction spring 17, and further the brake disc. It moves further to the side 3 by the wear of the control members 5A and 5B.
[0013]
In this way, the adjuster piston 14 is displaced relative to the adjuster pin 16 by the wear of the control members 5A and 5B. However, even if the adjuster piston 14 and the adjuster pin 16 are pulled back by the return spring 21 after braking. The state in which the adjuster piston 14 and the adjuster pin 16 are relatively displaced is held by the frictional force of the friction spring 17. Accordingly, the initial position of the support member 11 is shifted toward the brake disk 3 by the relative displacement of the adjuster piston 14 and the adjuster pin 16, that is, by the wear of the restrictors 5A and 5B, and eventually the restrictors 5A and 5B. The distance between the brake disc 3 and the brake disc 3 is kept constant.
[0014]
[Problems to be solved by the invention]
As described above, in the conventional disc brake device, an adjustment mechanism having a complicated structure is employed, which causes a high cost due to an increase in the number of parts.
[0015]
The present invention has been made paying attention to such problems, and an object of the present invention is to provide a disc brake device that can simply configure an adjustment mechanism that keeps a proper distance between a brake disc and a brake disc with a small number of parts. And
[0016]
[Means for Solving the Problems]
A first invention includes a brake disc that rotates integrally with each wheel of the vehicle, and a brake caliper that is attached to the vehicle side so as to be movable in the direction of the rotation axis of the brake disc. The brake caliper includes the brake disc. A disc brake device comprising: a pair of brake members sandwiching the shaft from both sides; a piston that pushes one of the pair of brake members toward the brake disc side; and a piston cylinder that accommodates the piston. Comprises a base end side piston capable of sliding in the piston cylinder from an initial position on the base end side to a sliding limit on the brake disc side, and urges the base end side piston to an initial position on the base end side. A first biasing means is provided, and hydraulic oil is supplied to the base end side piston base end side of the piston cylinder during braking. The base end side piston is moved from the initial position to the sliding limit by operating oil flowing into the first oil chamber during braking, and the base end side piston is formed. The housing portion coaxially houses the front end side piston, supports the control member on the front end side of the front end side piston, and defines a second oil chamber between the housing portion and the front end side piston, A check valve that allows only hydraulic oil to flow from the first oil chamber to the second oil chamber, and the pressure that the check valve presses and opens is applied to the biasing means when the proximal piston slides. It was set larger than the urging force.
[0017]
In the second aspect of the invention, the length from the initial position where the base end side piston moves to the sliding limit is made to coincide with the initial distance between the control wheel and the disc brake.
[0018]
In a third aspect of the invention, the check valve is built in the base end side piston.
[0019]
According to a fourth aspect of the present invention, a lid member that seals a side surface of the first oil chamber opposite to the base end side piston is fixed to the piston cylinder, and the first oil chamber is arranged on the center axis of the base end side piston. A through hole reaching from the oil chamber side to the second oil chamber is formed, and a shaft portion extending from the lid member is passed through the through hole, and oil reaching the tip end portion of the shaft portion is passed through the lid member. A drain hole was formed, and a stopper for closing the end of the oil drain hole was provided.
[0020]
According to a fifth aspect of the present invention, a predetermined gap is provided between the inner periphery of the piston cylinder and the outer periphery of the proximal end side piston, a predetermined gap is provided between the inner periphery of the housing portion and the outer periphery of the distal end side piston, A predetermined gap was provided between the hole inner periphery and the shaft outer periphery.
[0021]
In a sixth aspect of the present invention, a predetermined gap is provided between the inner periphery of the piston cylinder and the outer periphery of the proximal end side piston, and a predetermined gap is provided between the inner periphery of the housing portion and the outer periphery of the distal end side piston.
[0022]
Operation and effect of the invention
In the first and second inventions, when braking the vehicle, the hydraulic oil is supplied to the first oil chamber, and the base end side piston slides and extends from the initial position to the sliding limit, whereby the front end side piston The brake device supported by the is pushed out to the brake disc side. In this case, since the brake caliper can move in the direction of the rotation axis of the brake disc, the pair of brake members that have advanced by the amount of movement of the base end side piston eventually presses the brake disc between both sides, The wheel integrated with the brake disc is braked by the frictional force generated at this time. On the other hand, when the friction surface of the brake is worn down by such a braking operation, the brake does not reach the brake disc side only by the sliding amount of the base end side piston. As a result of the fact that the first oil chamber behind the piston cannot be expanded, the hydraulic pressure in the first oil chamber increases, the check valve is pressed open, and hydraulic oil flows from the first oil chamber to the second oil chamber. Inflow. As a result, the front end side piston is relatively displaced toward the brake disk side with respect to the base end side piston by an amount corresponding to the enlargement of the second oil chamber, and this relative displacement compensates for the wear of the restrictor. Further, since the backflow of the hydraulic oil from the second oil chamber to the first oil chamber is prohibited, the relative displacement between the front end side piston and the base end side piston is maintained even after the braking operation is completed. As a result, the distance between the disc brake and the disc brake that has advanced to the disc brake side by this relative displacement does not change from the initial state before wear of the disc brake, and the response of the brake operation is always constant and stable. It becomes. In addition, since the present invention is configured to have both the piston mechanism and the adjusting mechanism in the disc brake device, the configuration is remarkably simplified, the number of parts can be greatly reduced, and the cost is reduced. it can. In addition, the hydraulic oil filled in the first and second oil chambers also exhibits a heat insulating effect, and can suppress the transmission of high heat from the control wheel that becomes high temperature due to friction with the brake disc to the brake caliper side.
[0023]
In the third aspect of the invention, since the check valve is built in the proximal end side piston, the configuration can be further simplified.
[0024]
In the fourth aspect of the invention, if the plug of the oil drain hole is removed and the oil is drained from the second oil chamber, the tip side piston can be easily returned to the initial position before the wear of the control device without disassembling the piston. it can.
[0025]
In the fifth invention, since a gap is also provided between the inner periphery of the oil drain hole and the outer periphery of the shaft portion, the base end side piston can be inclined with respect to the lid member and the piston cylinder, and the front end side piston is Because it can tilt with respect to the proximal piston, this tilt can absorb the eccentric load applied to the piston and the tilt between the brake caliper and the brake disc. It is possible to prevent uneven wear due to the slanting contact with the brake disc.
[0026]
In the sixth aspect of the invention, the front end side piston is largely inclined by the double gap between the inner periphery of the piston cylinder and the outer periphery of the base end side piston and the gap between the inner periphery of the housing portion and the outer periphery of the front end side piston. This tilt can absorb the unbalanced load on the piston and the tilt of the brake caliper and brake disc. The piston and piston cylinder can be twisted, and the brake can be tilted and contact the brake disc. Uneven wear can be prevented.
[0027]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. The entire configuration of the disc brake device is the same as that shown in FIG.
[0028]
As shown in FIG. 1, the piston cylinder 31 is formed so as to penetrate the frame of the brake supporter support portion 4A. The proximal end side (left side in the figure) of the piston cylinder 31 is sealed with a lid member 33 via a seal member 32. On the other hand, on the distal end side (the right side in the figure) of the piston cylinder 31 facing the brake disk 3, the proximal piston 34 has a predetermined clearance (gap) between the inner peripheral surface of the piston cylinder 31. Hold it slidably.
[0029]
A step portion 34E facing the distal end side of the piston cylinder 31 is formed on the outer periphery of the proximal end side piston 34. From the opening at the distal end of the piston cylinder 31, the diameter of the tip portion of the proximal end side piston 34 from the step portion 34E is increased. The reduced tip portion 34F protrudes. Further, an annular locking portion 49 protruding to the inner peripheral side is formed at the opening at the tip of the piston cylinder 31. A clearance y is provided between the stepped portion 34E and the locking portion 49 in the sliding direction of the base end side piston 34, and the base end side piston 34 is where the stepped portion 34E contacts the locking portion 49. Up to the brake disk 3 side can be moved. This clearance y is set equal to the amount of movement of the control wheels 5A and 5B during braking.
[0030]
On the other hand, a shaft portion 33 </ b> A protrudes from the base end side lid member 33 of the base end side piston 34 toward the base end side piston 34. The shaft portion 33A is fitted into a through hole 34A formed on the central axis of the base end side piston 34 with a predetermined clearance, and the tip reaches an oil chamber 43 to be described later. A step portion 33B is formed at the base end of the shaft portion 33A, and a bottom surface 34A of the base end side piston 34 is supported in contact with the step portion 33B during non-braking.
[0031]
Further, a taper portion 33C that spreads outward is formed at the base of the step portion 33B of the lid member 33, and an oil chamber 35 is defined between the taper portion 33C and the bottom surface 34B. The oil chamber 35 is supplied with hydraulic oil from an oil passage 36 during braking. Thereby, the base end side piston 34 is pushed out to the brake disc 3 side against the return spring 40 provided between the step part 34D of the outer periphery of the base end side piston 34 and the frame of the brake supporter support part 4A. It is like that.
[0032]
A seal member 37 is provided between the outer periphery of the proximal piston 34 and the inner periphery of the piston cylinder 31, and a seal member 38 is provided on the outer periphery of the shaft portion 33A and the inner periphery of the through hole 34A, respectively, so that the oil chamber 35 is sealed. ing.
[0033]
A housing portion 34C is formed on the base end side piston 34 on the brake disk 3 side (right side in the drawing), and a coaxial front end side piston 41 is housed in the housing portion 34C. This front end side piston 41 supports the control wheel 5A via the heat insulating plate 42 at the front end. A predetermined clearance is provided between the inner periphery of the accommodating portion 34C and the outer periphery of the front end side piston 41 so that the axis of the front end side piston 41 can be slightly inclined with respect to the axis of the base end side piston 34. It has become.
[0034]
An oil chamber 43 is defined between the base end of the front end side piston 41 and the bottom of the accommodating portion 34C. The oil chamber 43 is interposed between the outer periphery of the front end side piston 41 and the inner periphery of the accommodating portion 34C. The seal member 44 is sealed. The hydraulic oil from the oil chamber 35 flows into the oil chamber 43 only through the check valve 45 built in the base end side piston 34.
[0035]
As a result, since the brake members 5A and 5B are worn, even if the base end side piston 34 is moved to the full movement range at the time of braking, that is, until it moves by the clearance y and contacts the locking portion 49, the brake member 5A is braked. When the oil does not reach the disk 3, the check valve 45 is pressed and opened by the increase of the oil pressure in the oil chamber 35, and the working oil flows into the oil chamber 43, and the oil chamber 43 is enlarged. That is, the cracking pressure of the check valve 45 is set to be larger than the spring force of the return spring 40 when the proximal end side piston 34 moves between the clearances y. Then, when the base end side piston 34 slides to the full sliding range and hydraulic oil further flows into the oil chamber 35 that can no longer be expanded, the hydraulic pressure in the oil chamber 35 is changed to the cracking pressure of the check valve 45 for the first time. The hydraulic oil flows into the oil chamber 43 beyond the above. In this manner, the front end side piston 41 is displaced relative to the base end side piston 34 toward the brake disc 3 side by an amount corresponding to the enlargement of the oil chamber 43, and the control member 5 </ b> A contacts the brake disc 3.
[0036]
In addition, since the hydraulic oil flowing into the oil chamber 43 is prevented from flowing back to the oil chamber 35 by the check valve 45, the oil chamber 43 is once expanded, and the front end side piston 41 is compared with the base end side piston 34. After the relative displacement, the relative displacement is maintained unless the hydraulic oil in the oil chamber 43 is extracted from the oil drain hole 33D that penetrates the central axis of the lid member 33 and reaches the tip of the shaft portion 33A. . The oil drain hole 33D is a hole for draining the oil from the oil chamber 43 (or air at the time of manufacture) in this way, and the base end side is usually sealed with a plug 39.
[0037]
Next, the operation will be described.
[0038]
When braking the railway vehicle, hydraulic oil introduced from the hydraulic pressure inlet 7 according to the brake signal is supplied into the oil chamber 35 through the oil passage 36 in the brake supporter support portion 4A. As a result, the oil chamber 35 is expanded, and the base end side piston 34 is disposed on the brake disk 3 side, and the length of the clearance y between the step portion 34E of the base end side piston 34 and the engaging portion 49 of the piston cylinder 31 opening. The control wheel 5A, which is pushed out by a length equal to the initial distance between the control wheels 5A, 5B and the brake disk 3, and supported by the tip side piston 41 is pressed against the brake disk 3 together with the control wheel 5B on the opposite side. The wheels are braked by the frictional force generated at this time.
[0039]
By the way, when the friction surfaces of the control members 5A and 5B are worn down by such a braking operation, the wear and the distance between the control members 5A and 5B and the brake disk 3 are widened. Therefore, even if the base end side piston 34 moves by the length of the clearance y, that is, in the full sliding range, the control members 5A and 5B do not come into contact with the brake disc 3.
[0040]
In this case, the oil pressure in the oil chamber 43 that can no longer be increased exceeds the cracking pressure of the check valve 45, the check valve 45 is pressed and opened, and the hydraulic oil flows into the oil chamber 43. When the hydraulic oil flows into the oil chamber 43 in this way, the distal end side piston 41 is displaced relative to the proximal end side piston 34, and the brake 5 </ b> A supported at the distal end of the distal end side piston 41 contacts the brake disc 3. It will be pushed out until it touches. That is, the front end side piston 41 is relatively displaced with respect to the base end side piston 34 by an amount corresponding to an increase in the distance between the control members 5A and 5B and the brake disk 3.
[0041]
On the other hand, since the hydraulic oil in the oil chamber 43 is prevented from flowing back into the oil chamber 35 by the check valve 45, the relative displacement of the front end side piston 41 with respect to the base end side piston 34 is maintained even after the end of the braking operation. . Therefore, the distance between the brake members 5A and 5B extending forward by the relative displacement and the brake disk 3 eventually returns to the distance equal to the length of the clearance y.
[0042]
As described above, according to the present invention, since the initial interval between the control members 5A and 5B and the brake disk 3 is always kept constant, it is possible to always give a constant and stable response to the brake operation.
[0043]
Further, in the present invention, the adjustment mechanism of the disc brake device can be simply configured with a small number of parts together with the piston mechanism, so that the cost can be reduced.
[0044]
Further, in the present invention, since the oil chamber 35 and the oil chamber 43 are filled with the working oil, the working oil has a heat insulating effect, and from the control 5A that becomes high temperature due to friction with the brake disc 3. There is an advantage that the heat is not easily transmitted to the control member support 4A side.
[0045]
Further, in the present invention, the proximal piston 34 is inclined with respect to the piston cylinder 31 and the lid member 33 and the distal piston 41 is inclined with respect to the proximal piston 34 by a clearance provided therebetween. Therefore, even if an uneven load is applied to the pistons 34 and 41 and the pistons 34 and 41 are to be bent with respect to the piston cylinder 31, this can be absorbed by the inclination of the front end side piston 41 and the base end side piston 34. It is possible to prevent twisting between the end side piston 34 and the piston cylinder 31.
[0046]
In the present invention, even when the brake disc 3 is tilted with respect to the brake supporter support portion 4A, such as during cornering, the control wheel 5A supported by the tip side piston 41 has the tip based on the double clearance described above. The inclination of the side piston 41 with respect to the control member 4A is absorbed by the control member 4A and the brake disk 3 so that the control member 5A and the brake disk 3 come into contact with each other without any inclination. Can prevent uneven wear.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing an embodiment of the present invention.
FIG. 2 is a front view showing the overall configuration of the disc brake device.
FIG. 3 is a cross-sectional view showing a conventional example.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Brake caliper 2A Arm 2B Arm 3 Brake disc 4A Brake supporter 4B Brake supporter 5A Brake 5B Brake 7 Hydraulic introduction hole 8 Mounting part 9 Support pin 31 Piston cylinder 32 Seal member 33 Lid member 33A Shaft 33B Step Part 33C Taper part 33D Oil drain hole 34 Base end side piston 34A Through hole 34B Bottom face 34C Housing part 35 Oil chamber 36 Oil passage 37 Seal member 38 Seal member 39 Plug 40 Return spring 41 Tip side piston 43 Oil chamber 44 Seal member 45 Check valve

Claims (6)

A brake disc that rotates integrally with each wheel of the vehicle, and a brake caliper that is mounted on the vehicle side so as to be movable in the direction of the rotation axis of the brake disc. A pair of brake calipers that sandwich the brake disc from both sides. A disc brake device comprising: a control device; a piston that pushes one of the pair of control devices toward the brake disc side; and a piston cylinder that accommodates the piston. A base end side piston capable of sliding in the piston cylinder from a position to a sliding limit on the brake disc side, and a biasing means for biasing the base end side piston to an initial position on the base end side; Defining a first oil chamber to which hydraulic oil is supplied during braking on the base end side piston base end side of the piston cylinder; When the hydraulic oil flows into the first oil chamber during operation, the base end side piston moves from the initial position to the sliding limit, and the housing formed on the base end side piston has a distal end side. A piston is accommodated coaxially, the control member is supported on the distal end side of the distal end side piston, a second oil chamber is defined between the accommodating portion and the distal end side piston, and the first oil chamber is formed. Provided with a check valve that allows only hydraulic oil to flow into the second oil chamber, and the pressure that the check valve presses and opens is set to be larger than the biasing force of the biasing means when the proximal piston slides A disc brake device characterized by that. 2. The disc brake device according to claim 1, wherein a length from an initial position at which the base end side piston moves to a sliding limit is made equal to an initial interval between the restrictor and the disc brake. The disc brake device according to claim 1 or 2, wherein the check valve is built in the base end side piston. A lid member that seals the side surface of the first oil chamber opposite to the base end side piston is fixed to the piston cylinder, and the first oil chamber side from the first oil chamber side is fixed to the center axis of the base end side piston. Forming a through hole reaching the second oil chamber, penetrating a shaft portion extending from the lid member through the through hole, and forming an oil drain hole reaching the tip portion of the shaft portion in the lid member; The disc brake device according to any one of claims 1 to 3, further comprising a stopper for closing an end of the oil drain hole. A predetermined gap is provided between the inner periphery of the piston cylinder and the outer periphery of the piston on the proximal end side, a predetermined gap is provided between the inner periphery of the housing portion and the outer periphery of the distal end side piston, and the inner periphery of the through hole and the shaft portion The disc brake device according to claim 4, wherein a predetermined gap is provided between the outer periphery and the outer periphery. 2. A predetermined gap is provided between the inner periphery of the piston cylinder and the outer periphery of the proximal end side piston, and a predetermined gap is provided between the inner periphery of the housing portion and the outer periphery of the distal end side piston. The disc brake device according to any one of claims 1 to 3.

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