JP3904396B2 - Actuator spring guide structure - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an operating device for driving a brake device such as a railway vehicle, and more particularly to a structure for guiding a spring of the operating device.
[0002]
[Prior art]
For example, an actuator (electric brake actuator) published in a pamphlet of International Publication No. WO98 / 47750 based on the Patent Cooperation Treaty moves a push rod for driving the brake device in the axial direction based on the rotation of the motor. A service brake mechanism and a safety brake mechanism for driving the piston to move the push rod in the axial direction by releasing the spring held in a compressed state. The spring in the safety brake mechanism portion needs to be arranged coaxially with the piston portion so as to apply a force to the piston portion without deviation. FIG. 4 is a partial sectional view of the actuating device showing the positional relationship between such a piston portion and a spring.
[0003]
In FIG. 4A, a metal-made cylindrical piston portion 101 is axially (vertical direction in the figure) with respect to a spring receiving member 103 which is a fixed portion via a resin sliding contact ring 102. It can move within a predetermined range. On the outer peripheral side of the piston portion 101, a spring (only the end portion of the spring is shown) 104 and a metal ring-shaped spring stopper member 105 that receives the spring 104 are mounted. The stopper members 105 are in sliding contact with each other at the sliding portion A. A retaining ring 106 is fitted on the outer periphery of the piston portion 101, and the spring retaining member 105 is in contact with the retaining ring 106 in the state shown in FIG. Note that the other end (not shown) of the spring 104 is received by the piston portion 101. Therefore, when the piston part 101 moves downward in the figure, the spring stopper member 105 and the spring 104 move in the same direction. At this time, sliding does not occur in the sliding portion A. On the contrary, when the piston part 101 moves upward in the figure, the spring stopper member 105 is already in contact with the spring receiving member 103 and does not move, and only the piston part 101 moves slightly upward as shown in FIG. Moving. At this time, the piston portion 101 slides at the sliding portion A with respect to the spring stopper member 105.
[0004]
In the operating device, when the safety brake mechanism is operated, the piston 101 moves from the state (b) through the state (a) further downward at a stroke, and the spring retaining member 105 is a spring receiving member. Leave 103. On the other hand, when the safety brake mechanism part returns from the operating state, the piston part 101 is pushed back to the state (a), and from here the piston part 101 is pushed against the spring 104, and the state shown in (b). It becomes.
[0005]
[Problems to be solved by the invention]
In the conventional operating device as described above, the service brake mechanism portion normally performs a brake operation, and the safety brake mechanism portion is in a standby state. In this case, the positional relationship between the piston portion 101 and the spring stopper member 105 is as shown in FIG. However, if the safety brake mechanism in the standby state is completely stationary, the operation of the service brake mechanism transmits a vibration with an amplitude of several millimeters and a frequency of several hertz to the piston 101. The part 101 reciprocates in small increments in the axial direction. Therefore, in the sliding portion A between the piston portion 101 and the spring stopper member 105, the sliding contact between the metals is repeated and heat is generated. As a result, seizure wear occurs in the sliding contact portion A, and the sliding resistance increases abruptly, causing malfunction of the piston portion 101.
[0006]
In view of the above-described conventional problems, an object of the present invention is to provide an operating device that prevents seizure wear in a safety brake mechanism.
[0007]
[Means for Solving the Problems]
The present invention is a spring guide structure of an operating device having a service brake mechanism that moves a push rod based on the output of a motor and a safety brake mechanism that moves the push rod based on the output of a spring, A piston part provided as one member of the safety brake mechanism part; a piston part for moving the push rod; and a spring disposed coaxially with the piston part and having one end locked to one end part in the axial direction of the piston part; A spring retaining member that is provided at the other end of the spring, is movable in the axial direction together with the other end, and forms a gap between the piston portion and is non-contact when arranged coaxially with the piston portion. A spring stop auxiliary member that is provided at the other axial end of the piston portion, aligns to a position coaxial with the piston portion by engagement with the spring stop member, and locks, If The stop member is in contact, and a spring receiving member to allow compression of the spring, when the safety brake mechanism is in the standby state, the spring stop assisting member is configured away from said spring holding member (Claim 1).
In the spring guide structure of the actuating device configured as described above, one end of the spring is locked to one end in the axial direction of the piston portion, and the other end is provided by a spring stop member and a spring stop auxiliary member engaged with the spring stop member. Locked. Further, the spring stopper member is aligned to a position coaxial with the piston portion by engagement with the spring stopper auxiliary member, and the spring stopper member is in a non-contact relationship with the piston portion. When the safety brake mechanism is in the standby state, the spring stopper auxiliary member is separated from the spring stopper member.
[0008]
Further, in the spring guide structure, the spring stop member has a tapered portion, by spring stop auxiliary member engages the tapered portion, is aligning to the spring stop member is a piston portion coaxially positions (Claim 2).
In this case, the engagement between the tapered portion and the spring stop auxiliary member, the tapered portion is moved so as to be cardiac adjusted to spring stop auxiliary member, the spring stop member is aligning the piston portion coaxially positions .
[0009]
Further, in the spring guide structure (claim 2), the spring receiving member may be one having a tapered portion for guiding so that the spring stop member to the piston portion coaxially position (claim 3).
In this case, the taper portion of the spring receiving member maintains the spring stopper member at a position coaxial with the piston portion.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a cross-sectional view showing a spring guide structure of an operating device according to an embodiment of the present invention. In the figure, the actuating device drives a motor in the housing 1 (however, partially protruding) constituted by a housing body 1a, an upper cover 1b, and a lid 1c attached to the upper cover 1b. And a safety brake mechanism unit 3 using a spring force as a driving source, and a push bar mechanism unit 4 driven by these mechanism units with the horizontal direction in the figure as an axial direction. ing. The safety brake mechanism 3 operates as an emergency brake only when the motor is not usable or when a power failure occurs.
[0011]
In the push rod mechanism 4, the guide tube 401 is held by the housing 1 so as to be slidable in the axial direction. The push rod 402 inserted into the guide tube 401 has a cylindrical shape except for the left end portion, and can slide in the axial direction with respect to the guide tube 401. The push rod 402 incorporates a ball screw, and a screw 403 constituting the ball screw is held so as to be rotatable around an axis. A pair of push rod rollers 404 are rotatably attached to both side surfaces of the guide tube 401. When the push rod roller 404 moves in the axial direction of the screw 403, the guide tube 401 moves accordingly. The pair of housing rollers 405 are attached to the housing 1 and are rotatable at the illustrated positions. A return spring (not shown) is mounted on the outer periphery of the guide tube 401. When the guide tube 401 moves to the left in the figure, the return spring is stored, and the guide tube 401 is biased in the return direction (right). The
On the other hand, the service brake mechanism 2 is provided with a motor 200. The screw 403 is rotated by a rotational output of the motor 200 via a power transmission mechanism (not shown).
[0012]
Further, in the safety brake mechanism section 3, a cylindrical guide sleeve 301 is provided on the inner peripheral side of the upper cover 1b. A metal spring receiving member 302 having a cylindrical portion 302a and a collar-like portion 302b is fitted on the guide sleeve 301 and is engaged with the upper cover 1b. The metal wedge piston 303 includes a cylindrical piston portion 303a that is externally inserted into the spring receiving member 302, a substantially disc-shaped spring support portion 303b, and a pair of wedge portions that are spaced apart from each other in a direction perpendicular to the paper surface. 303c. The lower ends of the two large and small springs 304 and 305 are locked to the spring support portion 303 b of the wedge piston 303. The upper end of the spring 304 is locked to the hook-shaped portion 302 b of the spring receiving portion 302. The upper end of the spring 305 is fixed to a ring-shaped spring stopper member 306. When the spring 305 is compressed (the state shown in the figure), the spring stopper member 306 is in contact with the flange portion 302b.
[0013]
A screw shaft 307 is screwed into a female screw formed at the center of the spring support portion 303b of the wedge piston 303, and the two constitute a relationship like a ball screw. A cylindrical pin support 308 is attached to the upper end side of the screw shaft 307. The cylindrical member 309 attached to the spring receiving member 302 has the same outer diameter as the pin support 308. A thrust bearing 310 is mounted between the pin support 308 and the cylindrical member 309. The locking sleeve 311 is inserted into the guide sleeve 301 with a gap in the radial direction. The locking spring 312 is wound around the outer periphery of the pin support 308 and the cylindrical member 309, and one end thereof is locked to the locking sleeve 311. An electromagnet 314 is attached to the lower end surface of the support ring 313 attached to the inner peripheral side of the guide sleeve 301, and the electromagnet 314 can electromagnetically attract the upper end portion 311 a of the locking sleeve 311. .
[0014]
The wedge piston 303 is movable in the axial direction when the screw shaft 307 rotates around the axis. A sliding contact ring 315 is attached to the inner periphery of the piston portion 303 a of the wedge piston 303, and this is in sliding contact with the cylindrical portion 302 a of the spring receiving member 302. Further, a slidable contact ring 316 is also mounted on the outer periphery of the spring support portion 303 b and slidably contacts the inner wall of the housing 1. The slidable contact rings 315 and 316 are made of a resin having high heat resistance and wear resistance and a relatively small friction coefficient.
[0015]
FIG. 2A is an enlarged cross-sectional view of the vicinity of the tip of the piston portion 303a shown in FIG. In (a), a ring-shaped spring stopper auxiliary member 317 is attached on the outer periphery in the vicinity of the tip of the piston portion 303a. The spring retaining auxiliary member 317 is formed such that the upper side inner circumference is larger than the lower side inner circumference so that a stepped portion 317a is formed on the inner circumferential surface. On the other hand, a circumferential groove 303d is formed on the outer peripheral surface of the piston portion 303a, and a retaining ring 318 is attached thereto.
[0016]
On the other hand, the aforementioned spring stop member 306 is fixed to the end of the spring 305. The spring retaining member 306 has a ring-like shape as a whole and includes a cylindrical portion 306a and an annular portion 306b, and the entire circumference of the corner portion between the inner surface side of the cylindrical portion 306a and the inner surface side of the annular portion 306b. In addition, a tapered portion 306c is formed. The tapered portion 306 c is shaped like a part of a conical surface, and the center line of the virtual cone coincides with the central axis of the spring stopper member 306.
[0017]
Further, the diameter of the circle drawn in the circumferential direction by the intersection P on the paper surface of the tapered portion 306c and the inner surface of the annular portion 306b in FIG. Further, the inner diameter of the annular portion 306b of the spring stopper member 306 is formed larger than the outer diameter of the piston portion 303a. Therefore, when the spring stopper member 306 is disposed coaxially with the piston portion 303a, a gap G is formed between them.
[0018]
Further, the upper end surface of the cylindrical portion 306a of the spring stopper member 306 is a tapered portion 306d. This tapered portion 306 d is also shaped like a part of a conical surface, and the center line of the virtual cone coincides with the central axis of the spring stopper member 306. On the other hand, a tapered portion 302c is also formed on the spring receiving member 302 with which the tapered portion 306d abuts. The tapered portion 302c is formed wider than the tapered portion 306d. The tapered portion 302c is also shaped like a part of a conical surface, and the center line of the virtual cone coincides with the central axis of the spring receiving member 302 and the central axis of the piston portion 303a.
[0019]
In order to attach the spring stopper auxiliary member 317 as described above, as shown in FIG. 5B, the spring 305 is compressed and the spring stopper member 306 is pressed, and the spring stopper auxiliary member 317 is externally fitted to the piston portion 303a. Push it back from the position. In this state, the retaining ring 318 is attached to the circumferential groove 303d, and then the spring 305 is released. As a result, the spring stop member 306 biased by the spring 305 contacts the spring stop auxiliary member 317, the spring stop auxiliary member 317 is pushed, and the retaining ring 318 and the step portion 317a are engaged (see (c)). ). Therefore, the spring stopper auxiliary member 317 does not move any further, and the spring stopper member 306 is locked by the spring stopper auxiliary member 317. Further, in the change from (b) to (c), when the tapered portion 306c of the spring stopper member 306 contacts the spring stopper auxiliary member 317, the spring stopper member 306 is guided (aligned) to the spring stopper auxiliary member 317. It is arranged coaxially with the spring stopper auxiliary member 317 and the piston part 303a. Therefore, a constant gap G is secured around the entire circumference between the spring stopper member 306 and the piston portion 303a.
[0020]
Further, when the tapered portion 306d of the spring retaining member 306 arranged coaxially with the piston portion 303a as described above comes into contact with the tapered portion 302c of the spring receiving member 302 (see FIG. 3A), the spring retaining member is provided. The member 306 is stably held by the spring receiving member 302 at the coaxial position. Further, from this state, the spring 305 received by the spring receiving member 302 can be compressed. Thereafter, when the piston portion 303 a further pushes against the spring 305, the state shown in FIG. 2A is obtained, and the spring stopper auxiliary member 317 is separated from the spring stopper member 306. Even in this state, a constant gap G is secured on the entire circumference between the spring stopper member 306 and the piston portion 303a. Thus, the spring stopper member 306 is disposed coaxially and non-contactingly with respect to the piston portion 303a.
[0021]
The operation of the actuator configured as described above will be described.
First, the service brake operation will be described. When the motor 200 rotates in a predetermined direction from the state shown in FIG. 1 (brake release state), the screw 403 rotates and the push rod 402 moves forward in the left direction in the figure. As the push rod 402 advances, a brake device (not shown) is activated. When the motor 200 rotates in the reverse direction, the push rod 402 moves backward and the brake is released.
[0022]
Next, the safety brake operation will be described. In the state shown in FIG. 1, the springs 304 and 305 are energized. Accordingly, the spring support portion 303b of the wedge piston 303 is urged downward, whereby the screw shaft 307 is urged in the rotational direction corresponding to the downward movement of the wedge piston 303. Accordingly, the locking sleeve 311 is also urged in a predetermined rotational direction via the pin support 308 and the locking spring 312. However, normally, the upper end portion 311 a of the locking sleeve 311 is electromagnetically attracted to the electromagnet 314. Accordingly, the locking sleeve 311 cannot rotate.
[0023]
From the above state, when the electromagnet 314 is demagnetized based on the safety brake command, the locking sleeve 311 is released and starts rotating. Following this, the pin support 308 and the screw shaft 307 also rotate, and the wedge piston 303 descends. When the wedge portion 303c of the descending wedge piston 303 enters between the push rod roller 404 and the housing roller 405, the movable push rod roller 404 moves to the left. Along with this, the guide tube 401 advances to the left together with the push rod 402. Thus, a brake device (not shown) is actuated by the push rod 402 that moves forward.
[0024]
As the wedge piston 303 descends, the spring stop assisting member 317 moves together with the piston portion 303a. Thereby, the spring stop member 306 changes from the state shown in FIG. 2A to the state shown in FIG. 3B through the state shown in FIG. 3A, and further moves together with the piston portion 303a. To do. In the change from FIG. 2A to FIG. 3A, the spring stop member 306 in FIG. 2A is not in the coaxial position with respect to the spring stop auxiliary member 317 and the piston portion 303a. Even when the taper portion 306c is guided (aligned) against the spring stop assisting member 317 and reaches the state shown in FIG. And it is coaxial with respect to the piston part 303a. Further, as described above, since the diameter of the circle drawn by the intersection point P (see FIG. 2A) is equal to the outer diameter of the spring stopper auxiliary member 317, the spring stopper member 306 after being guided is in the radial direction. No misalignment.
[0025]
In order to return the safety brake mechanism 3 once operated, the motor 200 can be operated and then rotated in a predetermined direction, and the screw 403 is rotated in the braking direction. At this time, since the push rod 402 has already been advanced by a predetermined stroke and applied the brake, it cannot be further advanced. Therefore, the rotational force of the screw 403 is converted into a force for retracting the screw 403 itself, and a force in the retracting direction is applied to the guide tube 401 and the push rod roller 404. When a force in the backward direction is applied to the push rod roller 404, a force in the upward direction is applied to the wedge piston 303. As a result, the wedge piston 303 rises while rotating the screw shaft 307, compresses the springs 304 and 305 again, and returns to the position shown in FIG.
Due to the rise of the wedge piston 303, the piston portion 303a, the spring stopper auxiliary member 317, and the spring stopper member 306 are changed from the state shown in FIG. 3B to the state shown in FIG. Return to state. At this time, since the spring stopper member 306 is maintained in advance in the same position as the auxiliary spring stopper member 317 and the piston portion 303a, a gap G between the piston portion 303a and the spring stopper member 306 is secured. Even if the spring stop assisting member 317 is separated from the spring stop member 306, the coaxial position of the spring stop member 306 is maintained by the contact between the tapered portion 302c of the spring receiving member 302 and the tapered portion 306d of the spring stop member 306. Maintained stably.
[0026]
On the other hand, when the safety brake mechanism unit 3 is in the standby state shown in FIG. 1, when the service brake mechanism unit 2 operates, the vibration accompanying the operation is also transmitted to the wedge piston 303. At this time, the wedge piston 303 vibrates little by little in the axial direction. However, as shown in FIG. 2A, there is a gap G between the piston portion 303a and the spring stopper member 306, and they are not in contact with each other, so there is no fear of heat generation due to sliding contact. Further, due to the presence of the sliding contact rings 315 and 316, the sliding contact between the metal between the wedge piston 303 and the housing 1 and between the wedge piston 303 and the spring receiving member 302 does not occur. Therefore, seizure wear does not occur.
[0027]
【The invention's effect】
The present invention configured as described above has the following effects.
According to the spring guide structure of the actuating device of claim 1, since the spring stopper member is aligned with the piston portion by engagement with the spring stopper auxiliary member, the spring stopper member is in non-contact relation with the piston portion. It becomes. Further, when the safety brake mechanism is in the standby state, the spring stopper auxiliary member is separated from the spring stopper member. Therefore, even if the piston portion vibrates in the axial direction, no friction is generated between the piston portion and the spring stopper member, and seizure wear does not occur.
[0028]
According to the spring guide structure of the actuating device according to claim 2, it is possible in easy easy structure, and cardiac adjust the spring stop member.
[0029]
According to the spring guide structure of the actuating device according to claim 3, the tapered portion of the spring receiving member, the spring stop member can be maintained in the sure fruit piston portion coaxially positions.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a spring guide structure of an actuator according to an embodiment of the present invention.
2A is an enlarged cross-sectional view showing the vicinity of a tip of a piston portion in the spring guide structure, and FIGS. 2B and 2C are cross-sectional views showing a mounting process of a spring stopper auxiliary member and the like. It is.
FIG. 3A is a cross-sectional view showing a state immediately before the spring retaining member in the spring guide structure is separated from the spring receiving member, or when the spring retaining member is in contact with the spring receiving member; ) Is a cross-sectional view showing a state where the spring stopper member is separated from the spring receiving member.
FIG. 4 is a partial sectional view showing a spring guide structure of a conventional actuator.
[Explanation of symbols]
2 Common brake mechanism part 3 Safety brake mechanism part 302 Spring receiving member 302c Taper part 303a Piston part 305 Spring 306 Spring stopper member 306c Taper part 306d Taper part 317 Spring stopper auxiliary member 402 Push rod

Claims (3)

A spring guide structure of an operating device having a service brake mechanism for moving a push rod based on an output of a motor and a safety brake mechanism for moving the push rod based on an output of a spring;
Provided as one member of the safety brake mechanism, and a piston for moving the push rod;
A spring disposed coaxially with the piston portion, one end of which is locked to one axial end portion of the piston portion;
A spring retaining member that is provided at the other end of the spring, is movable in the axial direction together with the other end, and forms a gap between the piston portion and is non-contact when arranged coaxially with the piston portion. When,
A spring stop auxiliary member that is provided at the other axial end of the piston part, aligns and coordinates with the piston part by engagement with the spring stop member, and
A spring receiving member that abuts on the spring stop member and compresses the spring;
The spring guide structure of an operating device, wherein the spring stop auxiliary member is separated from the spring stop member when the safety brake mechanism is in a standby state. The spring stop member has a taper portion, and the spring stop member is aligned with the piston portion so that the spring stop member is coaxial with the taper portion when the spring stop auxiliary member is engaged with the taper portion. The spring guide structure of the actuator described. The spring guide structure for an operating device according to claim 2, wherein the spring receiving member has a tapered portion that guides the spring stopping member so as to be coaxial with the piston portion.

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