JPS62266234A - Spring brake cylinder - Google Patents

Abstract

PURPOSE:To easily effect the operation of a spring brake, by moving a transmitting rod in a braking direction under the condition where a second cylinder member remains engaged with a first cylinder member by a clutch. CONSTITUTION:When a pressure air is supplied from a suction/exhaust port 34, a second cylinder member 32 is moved rightward to engage a clutch 39. Simultaneously, the pressure air is supplied through a passage 35 into a second pressure chamber 48. As a result, a spring 36 is compressed to move a piston 33 leftward and also move a transmitting rod leftward, thus making a spring brake into a released condition by the air pressure. Accordingly, when the suction/exhaust port 34 is opened to the atmosphere, the spring 36 is expanded to move the transmitting rod 37 rightward, thereby effecting the operation of the spring brake. Thus, the spring brake can be easily attained.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a spring brake cylinder that applies a brake to the wheels, discs, etc. of a vehicle using a spring force, and particularly relates to a spring brake cylinder that can be manually released from a spring brake operating state. This spring brake cylinder is used by being incorporated into a brake unit, or by being connected to a basic brake device via a lever.

<Prior art> As a conventional technology of this kind, Japanese Patent Application Laid-Open No. 51-41157
There is one described in Publication No. 6. Its schematic structure is shown in FIG.
and a brake spring 3 that presses the piston 2 in one direction, and is fixed to the piston 2.

A piston sleeve 5 that rotatably holds a nut 4 is provided in the inner hole, and a threaded spindle 6 that is screwed onto the nut 4 is provided so that the nut 4 rotates with the outer periphery of the extended portion and is axially relative to the nut 4. A movably fitted control ring 7 is provided, and is constrained from radially outward via a spring 8 against teeth provided on the outer periphery of the control ring 7 and inclined to one side to rotate in one direction. A permissively engaged plunger 9 is provided. The cylindrical part 10°11 in the figure is a guide for the axial movement of the piston sleeve 5,
One end of the threaded spindle 6 is fitted airtightly and slidably into the inner hole 18 of the cylindrical portion 10, and the post 20 of the spindle/L/6 is engaged with the groove 19 of the inner hole 18 to rotate around the shaft. Rotation is not restricted. 12 is a pressure air supply/discharge port, 13 is a cylinder chamber, and 14 is a bull ring. This spring brake cylinder 15 is provided with a service brake cylinder 16 adjacent to the cylinder chamber 13, and one end of the threaded spindle 6 abuts against a service brake piston 17 in a brake release state.

When pressurized air is supplied to the cylinder chamber 13, the piston 2 moves to the right in the figure against the spring 3 and reaches the brake release position shown in the figure. When the pressurized air is discharged, the action of the spring 3 The piston 2 moves to the left and reaches the braking position. In this brake action state, the piston 2 moves to the left together with the piston sleeve 5, nut 4, and spindle 6, and one end of the spindle 6 pushes the service brake piston 17 to the left.

When this brake is applied, that is, the brake system as a whole is in a state where the pressure air in the service brake cylinder 16 is discharged and the brake is released, and the spring brake cylinder 1
When the pressurized air 5 is discharged and the spring brake by the spring 3 is applied, the brake is released by manually pulling the bull ring 14. When the bull ring 14 is pulled, the control ring 7 and nut 4 are released from the restraint by the plunger 9 and become rotatable, and the service brake piston 17
The spindle 6, which is being pushed back from the side, moves to the right while rotating the nut 4 and control ring 7 via the threaded portion, and the service brake piston 17 returns to the position shown. This will prevent the brakes from loosening. When pressurized air is supplied to the cylinder chamber 13 in this manually released state of the spring brake, the piston 2 is pushed to the right, so the piston sleeve 5 pushes the nut 4 in the axial direction, and the nut 4 together with the control ring 7 which is rotatable in this direction and moves along the threaded portion of the spindle 6 back to the state shown.

<Problems to be Solved by the Invention> The conventional spring brake cylinder described above has a part that converts a linear force into a rotational force in the middle of the transmission path of a huge force for braking, and is quite complicated. It is a mechanism. Therefore, in order to ensure smooth operation with the conversion part, that is, relative movement between the piston and the spindle/L/A, the threads of the spindle and nut must be elaborate multi-thread threads, and bearings must be provided. It is also necessary to have the strength to be able to transmit a very large force. Further, in such a configuration, since there are many mechanical contact parts for transmitting force, consideration must be given to wear between the control ring and the plunger, including the engagement part thereof. Therefore, in order to manufacture a spring brake cylinder that satisfies these requirements.

There is a problem that it is expensive and that it is difficult to ensure durability.

The technical problem of this invention is to simplify the mechanism and ensure reliability and durability so as not to impair the original function.

<Means for Solving the Problems> The means of the present invention includes a first cylinder body, which is slidably housed in the first cylinder body in the form of a piston, and has a first pressure on one side within the first cylinder body. a second cylinder body forming a chamber, and a piston housed in the second cylinder body so as to partition the first pressure chamber side in the second cylinder body into a spring chamber and the other side into a second pressure chamber. , a pressure air supply/discharge port provided for the first pressure chamber, a communication path communicating the first pressure chamber and the second pressure chamber, and a spring brake spring housed in the spring chamber. a brake force transmission rod extending from the piston to one side along the axis and passing through an end wall of the second cylinder body and an end wall of the first cylinder body to reach the outside; and a second cylinder body. a cylinder guide protruding along the axis from one end wall of the first cylinder body and entering a guide hole provided in the end wall of the first cylinder body; and a cylinder guide provided between the cylinder guide and the end wall of the first cylinder body. The second cylinder body is provided with a clutch having an external manual operation portion that locks the second cylinder body in a movement position when pressurized air acts on the first pressure chamber and releases the lock.

<Function> In the above means, when pressurized air is supplied to the first pressure chamber from the supply/discharge port, the clutch moves to the first pressure chamber at a position where the second cylinder body moves to the end opposite to the first pressure chamber of the first cylinder body. Since the second cylinder body is locked to the cylinder body and pressurized air is supplied to the second pressure chamber via the communication path, the piston compresses the spring and moves. This state is the brake release state. If it is necessary for the transmission rod to move back toward the first cylinder body when the brake is released, the transmission rod should be configured to extend from the piston to the side opposite to the spring, so that the transmission rod can move back toward the first cylinder body when the brake is released. If it is necessary to advance outward from the piston, the transmission rod may be configured to extend from the piston toward the spring side.

When the supply and exhaust ports are opened to the atmosphere from this brake-released state, the spring brake is activated. That is, the second cylinder body remains locked to the first cylinder body by the clutch, and the pressure in the second pressure chamber becomes atmospheric pressure, causing the spring to expand and move the transmission rod in the direction of brake application via the piston. From this, the splash brake is activated. In addition, when pressurized air is supplied from the supply/discharge port from this brake application state, the original brake release state is restored.

When the clutch is manually released from the brake applied state,
The second one, which supported one end of the spring that gave the braking action,
Since the cylinder body is released from the first cylinder body, it is displaced toward the first pressure chamber and the brake is released.

<Example> A first example is shown in FIGS. 1 to 3. In the figure, 3
0 indicates the entire spring brake cylinder, 31 is the first cylinder body, 32 is the second cylinder body, 33 is the piston, 34
35 is a communication passage, 36 is a spring for a spring brake, 37 is a transmission rod, 38 is a cylinder guide, and 39 is a clutch.

The first cylinder body 31 has both end walls 40 and 41, and the end walls 40 are provided with a supply/discharge port 34 and a clutch 39. .

The second cylinder body 32 is slidably provided in the first cylinder body 31 in a piston-like manner, and has both end walls 42 and 43,
A piston rod-shaped cylinder guide 38 extends from the end wall 42 and reaches into an inner hole 44 provided in the end wall 40 of the first cylinder body 31, forming a part of a clutch 39 to be described later. There is. 45 in the figure is a sealing member,
A first pressure chamber 46 communicates with the supply/discharge port 34 .

A first pressure chamber 46 partitioned by the piston 33 is a spring chamber 47, and the other is a second pressure chamber 48. The second pressure chamber 48 and the first pressure chamber 46 are always in communication through a communication path 35 formed of a groove and a hole provided in the second cylinder body 32. In the figure, 49 is a sealing member, and 50 is a stopper protruding from the piston 33 side.

The spring 36 is a strong claw-type coil spring housed in a compressed state in the spring chamber 47, and constantly presses the piston 33 to the right in the figure.

The transmission rod 37 has one end coupled to the piston 33, and the other end hermetically extends to the outside through the end wall 43 of the second cylinder body 32. Although not shown, the transmission rod 37 is pressed by the brake system to transmit braking force. It is related to the part that occurs.

The clutch 39 is a ball type clutch that locks the axial movement of the cylinder guide 38 to the first cylinder body 3 side. The clutch 39 is fixedly provided to a ball engaging groove 51 formed on the outer periphery of the end of the cylinder guide 38, a pawl 52, and an end wall 40 of the first cylinder body 31, and is fixedly provided to the end wall 40 of the first cylinder body 31.
The cylindrical part 55 has a cylindrical shape with an inner hole 53 into which the pole 52 is fitted, and is provided with a ball holding hole 54 that holds the pole 52 so that it can be displaced in the radial direction.
A control member 59 having an inner circumferential surface 56 and a groove 58 with a tapered portion 57 for controlling the state of protruding from the inner circumferential surface of the coil spring 5 and the state of protruding from the inner circumferential surface of the coil spring to the outer circumferential surface without protruding from the inner circumferential surface of the control member 59; 60, it is composed of a lid body 61 holding a control member 59. In the figure, 62 is a rubber man bar, and 63 is a sealing member.

1 and 2 show the clutch engaged state, in which the inner circumferential surface 56 of the control member 59 restricts the state in which the pawl 52 is engaged with the pawl engaging groove 51, and from this state, the outer surface of the cover 62 is When the control member 59 is pushed to the right against the spring 60, the position of the groove 58 coincides with the position of the pawl 52, and the ball 52 is displaced toward the groove 58 by the axial movement force of the cylinder guide 38. The clutch will not disengage, and the result will be as shown in Figure 3. In the state shown in the figure, the control member 59 is connected to the spring 60.
Since the cylinder guide 38 is biased to the left by
moves to the right and when the groove 51 matches the position of the ball 52, the pawl 52 is pushed by the tapered portion 57 of the groove 58 and is displaced toward the groove 51, and the clutch automatically returns to the above-mentioned engaged state. .

When this spring brake cylinder 30 is supplied with pressurized air from the supply/discharge port 34, the second cylinder body 32 moves to the right as shown in FIG. 1, the clutch 39 becomes engaged, and the second pressure Pressurized air is also supplied into the chamber 48 through the passage 35, compressing the spring 36, causing the piston 33 to move to the left, and the transmission rod 37 to move to the left. This is a pneumatic spring brake release condition.

When the supply/discharge port 34 is opened from this brake released state, the spring 36 is expanded and the transmission rod 37 is pressed to the right, resulting in a spring brake action state as shown in FIG.

From this braking state, when the control member 59 is manually depressed to the right to disengage the clutch 39, the second cylinder body 32 moves to the left and the position supporting the spring 36 moves backward. , the transmission rod 37 moves back to the left and the brake is released. The kneading is in a state where the spring brake is manually released.

In this relaxed state, when pressurized air is supplied from the supply/discharge port 34, the spring brake is returned to the air pressure released state shown in FIG.

A second embodiment is shown in FIG. This spring brake cylinder 7o has a transmission rod 37 that protrudes in the same direction as in the first embodiment.
The brake lever a is configured to generate a braking force by retracting to the left, and its direction of action is opposite to that of the first embodiment.

The main differences in the structure are the supply/discharge port 34a and the communication path 35a.
, first pressure chamber 46b1 spring chamber 47a1 second pressure chamber 48a
, the seal member 45a, the stopper 50a, etc. are provided on the opposite sides from those of the first embodiment. Since the other parts are the same as those in the first embodiment, the same parts are given the same reference numerals in the drawings and their explanation will be omitted.

The state shown in FIG. 4 of this spring brake cylinder 70 is a state in which the spring brake is loosened by pressure pneumatics supplied with pressurized air, and when the pressure air is discharged, the spring 36 expands to the left and the piston 33 moves as shown in the figure. Move to the left and press the transmission rod 37a.
moves to the left to enter the spring brake applied state, and when the control member 59 is manually depressed to the right, the clutch 39 is disengaged and the second cylinder body 32 moves to the right to enter the spring brake manual release state. Become.

A third embodiment is shown in FIGS. 5 and 6. The spring brake cylinder 80 of this embodiment has a configuration in which the transmission rod 37b, which protrudes in the opposite direction to that of the first embodiment in FIG. 5, retracts to the right and generates a braking force. The main difference in structure compared to the first embodiment is that the transmission rod 37b passes through the center of the clutch 39b, and the control member 59b of the clutch 39b can be rotated.

The transmission rod 37b passes through the center of the spring 36 from the piston 33, passes through the center hole formed in the cylinder guide 38b in an airtight manner, and comes out to the outside.

In the clutch 391), the cylindrical portion 55t) is formed slightly shorter, the groove 58b of the control member 59b is formed along the axial direction corresponding to each ball 52, and one inner surface has an inclined surface s+.
b, and a lever 81 for turning operation is provided on a part of the outer periphery, and one end of the lever 81 protrudes to the outside through a long hole provided in the lid body 6xb that allows a predetermined turning to operate a handle 82. It is provided.

Further, the spring 60'b is biased with a rotational force in a direction to restore the stiffness to a predetermined operating direction of the lever 81 (clockwise in FIG. 6). Since the other parts are the same as those in the first embodiment, the same parts are given the same reference numerals in the drawings and their explanation will be omitted.

In this spring brake cylinder 80, the state shown in FIG. 5 is a state in which the spring brake is released by pressurized air, and when the pressure air is discharged, the spring 36 expands and the piston 33 moves to the right in the figure, and the transmission rod 37b also moves to the right and enters the spring brake applied state, and when the handle 82 is manually operated and the control member 59b is rotated clockwise in FIG. 6 via the lever 81, the clutch 39b becomes disengaged. The second piston body 32 moves to the left in FIG. 5, and thereby the transmission rod 37b also moves to the left to enter the spring brake manual release state. If pressurized air is supplied from the supply/discharge port 34 in this state, the system automatically returns to the state in which the spring brake is loosened by pressurized air as shown in FIG.

As in the third embodiment, the clutch portion 39b is connected to the transmission rod 37.
b is a penetrating type, and in order for the transmission rod 37b to act as a spring brake by pushing action, the supply/discharge port 34, the communication passage 35, the first pressure chamber 46, the spring chamber 47, and the second pressure chamber in the same embodiment are required. Chamber 48, seal member 45, stopper 50
．． 63 etc. should be provided with the right and left sides reversed as in the second embodiment. The explanation about the kneading will be omitted.

<Effects of the Invention> According to the present invention, although the spring brake cylinder has a configuration with a manual loosening function as in the conventional spring brake cylinder, it does not require a multi-thread screw or the like, and the parts that require high-precision machining as a whole can be used. It has a simple structure with almost no problems, and therefore has extremely high reliability and durability.

In addition, the brake force transmission rod can be made to protrude to either side along the axis of the first cylinder body and the clutch provided at one end thereof, and the braking force can be applied to the first cylinder body and the clutch provided at one end thereof. It is possible to select either the pushing direction or the pulling direction of the transmission rod. Kneading expands the types of brake devices that can be applied.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional side view of a first embodiment of the invention, FIGS. 2 and 3 are longitudinal sectional views of the same embodiment in different states from FIG. 1, and FIG. 4 is a longitudinal sectional view of the second embodiment of the invention. FIG. 5 is a longitudinal sectional view of the third embodiment, FIG. 6 is a sectional view taken along line A-A in FIG. 5, and FIG. 7 is a partial longitudinal sectional view showing an example of a conventional spring brake cylinder. It is a front view. 30, 70.80... Spring brake cylinder, 31
...First cylinder body, 32...Second cylinder body, 3
3... Piston, 34.34a... Supply/discharge port, 35
, 35a... Communication path, 36... Spring for spring brake, 37. 37a, 371)... Transmission rod, 38.
38a, :sab...Sender guide, 3
9.39b...Clutch, 46.46al...1st
Pressure chamber, 47.47a... Spring chamber, 48.48a...
・Second pressure chamber. Patent applicant: Japan Air Brake Co., Ltd. Agent
Tetsu Shimizu and 2 other famous confections, 1 illustration of iris, 20 iris, 3M father-in-law, 5 illustrations, 7 illustrations of father-in-law, Supplementary IF book (1 shot) January 1981, 811 4IF, ;'l Director-General Kuro 111 Akio-dono
'l ・Display of 11 patent applications 1986-109172 2 Name of the invention Spring Flexi Linta 3 Person making the supplementary market・Relationship with 1 Listed Patent applicant 4 Agent Zip code R365+ Address Kumoi, Chuo-ku, Kobe City Street 7-chome El 1-] Name
(6299) Ill Hiroshi Naka・””1. ,,
), near 1, :゛address same 1-・'' 5 Column ``Detailed Description of the Invention 14 If J'' of the specification to be amended. 6 Correct the words and phrases in the description of the amendment as per the dotted line errata. Next

Claims (1)

[Claims] (1) A first cylinder body, a second cylinder body that is slidably accommodated in the first cylinder body in the shape of a piston and forms a first pressure chamber on one side within the first cylinder body; A piston housed in the second cylinder body so as to partition the first pressure chamber side in the second cylinder body into a spring chamber and the other side into a second pressure chamber, and a pressure provided to the first pressure chamber. An air supply/exhaust port, a communication path communicating the first pressure chamber and the second pressure chamber, a spring for a spring brake housed in the spring chamber, and a spring extending from the piston to one side along the axis. a brake force transmission rod that extends and extends through the end wall of the second cylinder body and the end wall of the first cylinder body to reach the outside;
A cylinder guide protrudes along the axis from one end wall of the cylinder body and enters a guide hole provided in the end wall of the first cylinder body, and a cylinder guide provided between the cylinder guide and the end wall of the first cylinder body. A spring brake cylinder, comprising: a clutch having an external manual operation part that locks and releases the second cylinder body in a moving position when pressurized air acts on the first pressure chamber.