JP2548278Y2 - Brake cylinder with automatic clearance adjustment device - Google Patents

Description

[Detailed description of the invention]

[0001]

The brake cylinder with an automatic clearance adjusting device according to the present invention is assembled on a back plate constituting a drum brake to constitute a braking device for an automobile, and the lining of a brake shoe is worn out. When the gap between the lining and the inner peripheral surface of the drum tends to increase, the brake shoe is moved toward the inner peripheral surface of the drum to prevent the clearance from becoming too large. .

[0002]

2. Description of the Related Art For example, in the case of a drum brake for braking an automobile, a pair of brake shoes are mounted on a back plate provided inside wheels so as to be freely displaceable in a radial direction, and also on the back plate. It is configured by fixing the brake cylinder. At the time of braking, the pair of brake shoes are pushed radially outward by supply of pressure oil to the brake cylinder, and the outer peripheral surface of the lining provided on each brake shoe is moved to the inner peripheral surface of the drum that rotates together with the wheels. And the braking force is obtained by the frictional force acting between both sides.

When the lining of the brake shoe is worn due to repetition of braking and the gap between the outer peripheral surface of the lining and the inner peripheral surface of the brake drum is increased, if the gap is left as it is, The amount of displacement of the brake shoes required until the outer peripheral surface of the brake shoe and the inner peripheral surface of the drum friction with each other increases. As a result, the amount of depression of the brake pedal required at the time of braking increases, and not only does the interval at the time of braking become worse, but also when sufficient, sufficient braking cannot be performed.

In order to solve such inconvenience, conventionally,
If the lining of the brake shoe wears and the gap between the lining and the inner peripheral surface of the drum tends to increase, move the brake shoe toward the inner peripheral surface of the drum, and 2. Description of the Related Art A brake cylinder with an automatic clearance adjusting device (so-called auto slack adjuster) for preventing the size from becoming too large has been widely used.

FIGS. 6 and 7 show a first example of a brake cylinder with an automatic clearance adjusting device conventionally used for the above-described purpose. Reference numeral 1 denotes a cylinder body, which is formed in a cylindrical shape with both ends opened. This cylinder body 1
The pair of brake shoes (not shown) is fixed to the back plate between the ends of the pair.

[0006] A pair of piston bodies 2 are inserted into the cylinder body 1 from both ends of the cylinder body 1. A packing 3 is mounted on the outer peripheral surface of the inner end of each piston main body 2 (the end near the center of the cylinder main body 1), and the oil tightness between the inner peripheral surface of the cylinder main body 1 and the outer peripheral surface of each piston main body 2 is provided. I am trying to keep it. Each piston body 2 is formed in a cylindrical shape with a bottom, and a bottomed circular hole 5 is provided inside, and the opening of the circular hole 5 faces the outside of the cylinder body 1.

An oil supply port 4 is provided at the center of the cylinder body 1 so that pressure oil can be sent into the cylinder body 1 freely. That is, by sending pressure oil into the cylinder body 1 from the oil supply port 4, the pair of piston bodies 2 can be pushed out of the cylinder body 1.

An adjusting cylinder 6 is rotatably mounted inside the circular hole 5 of each piston body 2. A female screw 7 is formed on the inner peripheral surface of each adjusting cylinder 6, and an adjusting bolt 8 is screwed onto the female screw 7.
The tip of each adjusting bolt 8 is projected from the outer end of the adjusting cylinder 6.
An edge of a web (not shown) constituting the brake shoe is engaged. In this way, by engaging the edge of the web with the engagement recess 9, the adjustment bolt 8 is made unrotatable.

A sleeve 10 is provided on the outer peripheral surface of the adjusting cylinder 6.
However, only the displacement in the axial direction of the adjusting cylinder 6 (the left-right direction in FIG. 6) is freely fitted. That is, the engagement protrusion 1 is provided on the inner peripheral edge of one end (the right end in FIG. 6) of the sleeve 10.
The engaging projection 11 is engaged with an engaging groove 12 provided in the outer peripheral surface of the adjusting cylinder 6 in the axial direction.
The first ratchet teeth 13 are provided on the outer peripheral surface of the sleeve 10 in the circumferential direction. The first ratchet teeth 13 are inclined with respect to the axial direction.
Further, a compression spring 14 is provided between a flange 22 formed on the outer peripheral edge of the outer end of the adjusting cylinder 6 and the outer peripheral edge of the sleeve 10 so as to apply an inward elastic force to the sleeve 10. doing.

On the other hand, a long hole 15 extending in the axial direction is provided at a position on the side surface of the piston body 2 where the first ratchet tooth 13 is aligned. A guide hole 16 is provided in a part of the cylinder main body 1 which is aligned with the elongated hole 15 in a radial direction of the cylinder main body 1 (vertical direction in FIG. 6). A ratchet pin 17 is fitted in the guide hole 16 via a sleeve 18 so as to be freely displaceable in the radial direction of the cylinder body 1, and a distal end portion (a lower end portion in FIG. 6) of the ratchet pin 17 is attached to the guide hole 16. And the slot 15.

The ratchet pin 17 has a second ratchet tooth 19 formed on the distal end face thereof so as to be able to mesh with the first ratchet tooth 13. Further, a compression spring 21 is provided between the lid 20 that closes the outer end opening of the guide hole 16 and the ratchet pin 17, and the tip end face of the ratchet pin 17 faces the first ratchet tooth 13. Pressing.

The first and second ratchet teeth 1
By appropriately setting the inclination directions of the screw 3 and 19, and the screw direction of the female screw 7 formed on the inner circumferential surface of the adjusting cylinder 6 and the adjusting bolt 8 screwed with the female screw 7, the outer circumferential surface of the lining can be adjusted. The gap between the drum and the inner peripheral surface is adjustable.

That is, by supplying and discharging pressure oil into the cylinder body 1 through the oil supply port 4, the piston body 2
Is moved in a direction protruding from the cylinder body 1, the inclined surfaces of the first and second ratchet teeth 13 and 19 slide with each other, thereby causing the two ratchet teeth 13 and 19 to slide.
Does not mesh with each other, but when the brake shoe is released, the interval between the brake shoes is reduced by the elasticity of the return spring, and when the piston body 2 is pushed into the cylinder body 1, the two ratchet teeth 13 , 19 are inclined with each other so that the ratchet teeth 13, 19 are inclined with each other.

The first and second ratchet teeth 13 and 19 are engaged with each other in accordance with the release of braking, and the adjusting cylinder 6 is rotated. In this case, the amount of protrusion of the adjusting bolt 8 from the adjusting cylinder 6 is determined to be increased based on the screwing of the adjusting bolt 8 with the female screw 7 on the inner peripheral surface of the adjusting cylinder 6.

In the case of the brake cylinder with the automatic clearance adjusting device constructed as described above, when braking is performed, pressure oil is supplied into the cylinder body 1 through an oil supply port 4 provided at the center of the cylinder body 1. Send in. As a result, the cylinder body 1
The interval between the pair of piston bodies 2 fitted inside is widened,
Each piston body 2 is pushed out of the cylinder body 1.
The tip of the adjusting bolt 8 supported by each piston body 2 via the adjusting cylinder 6 is abutted against the pair of brake shoe webs as described above, so that the piston body 2 is pushed out. As a result, the interval between the pair of brake shoes is widened, and the outer peripheral surface of the lining of each brake shoe is strongly pressed against the inner peripheral surface of the drum to perform braking.

When the lining of the pair of brake shoes has little wear and the gap between the outer peripheral surface of the lining and the inner peripheral surface of the drum is narrow, the amount of movement of the piston body 2 during braking is small. The first and second ratchet teeth 13 and 19 remain in contact with each other.
That is, even if the adjusting cylinder 6 provided with the first ratchet teeth 13 on the outer peripheral surface via the sleeve 10 is displaced together with the piston main body 2, the amount of the displacement is small, so that the adjusting main body 6 does not displace in the axial direction of the cylinder main body 1. The second ratchet teeth 19 on the tip end face of the ratchet pin 17 are the peaks (teeth) of the first ratchet teeth 13.
Never exceed. Therefore, even if the piston main body 2 is pushed into the cylinder main body 1 with the release of braking, the sleeve 10 and the adjusting cylinder 6 do not rotate, and the amount of protrusion of the adjusting bolt 8 is the same as that before braking. Will be kept as is.

When the lining wears due to the repetition of braking, and the distance between the outer peripheral surface of the lining and the inner peripheral surface of the drum increases, the amount of movement of the piston body 2 at the time of braking increases. Along with the sleeve 1 on the outer surface
When the adjusting cylinder 6 provided with the first ratchet teeth 13 is displaced together with the piston main body 2 through the first ratchet teeth 0, the second ratchet teeth 19 on the tip end face of the ratchet pin 17 which do not displace in the axial direction of the cylinder main body 1 Mountain of teeth 13 (teeth)
Beyond.

Therefore, when the piston main body 2 is pushed into the cylinder main body 1 with the release of the braking, the second ratchet teeth 19 mesh with a mountain different from the mountain which had meshed before (before braking). I do. As a result, when the piston main body 2 is pushed into the cylinder main body 1 with the release of braking, the sleeve 10 and the adjusting cylinder 6 rotate. As a result of the rotation of the adjusting cylinder 6, the amount of protrusion of the adjusting bolt 8 is increased as compared to the state before the braking, and the gap between the outer peripheral surface of the lining of each brake shoe and the inner peripheral surface of the drum is reduced.

In the case of the structure shown in FIGS. 6 and 7, the first ratchet teeth 13 are not formed directly on the outer peripheral surface of the adjusting cylinder 6, but only the axial displacement of the adjusting cylinder 6 is allowed. The first ratchet tooth 1
And forming the sleeve 10 with a compression spring 14
To press the piston body 2 toward the inner end thereof. The elasticity of the compression spring 14 is made slightly weaker than the elasticity of the return spring for returning the pair of brake shoes to the non-braking state.

Therefore, after braking is performed in a state in which the gap between the outer peripheral surface of the lining and the inner peripheral surface of the drum is widened, the sleeve 10 is once compressed (by the elastic force of the return spring). Move toward the outer end of the piston body 2 against the elasticity of the piston body 2. Then, after each brake shoe returns to the original position by the elasticity of the return spring, the sleeve 10 moves toward the inner end of the piston body 2 by the elasticity of the compression spring 14 while the adjusting cylinder 6 To increase the amount of protrusion of the adjustment bolt 8.

However, even if the first ratchet teeth 13 are formed directly on the outer peripheral surface of the adjusting cylinder 6, the lining is similarly formed except that the adjusting cylinder 6 is rotated at the same time when the piston body 2 is pushed by the return spring. The gap between the outer peripheral surface of the drum and the inner peripheral surface of the drum can be adjusted.

FIG. 8 shows a second example of a conventionally used brake cylinder with an automatic clearance adjusting device. In the case of the structure of the second example, by sending pressure oil into the cylinder body 1 during normal braking, the interval between the pair of piston bodies 2, 2 fitted in the cylinder body 1 is expanded, At the time of parking, the space between the pair of piston bodies 2, 2 can be expanded by pushing the wedge 23.

That is, the inner surfaces of the pair of piston bodies 2 and 2 are formed with inclined surfaces 24 and 24 inclined in opposite directions to each other. At right angles to the auxiliary cylinder 25
A rod 26 is provided in the sub-cylinder portion 25 so as to be displaceable in the axial direction of the sub-cylinder portion 25, and the wedge 23 is fixed to the tip of the rod 26. Then, both side surfaces of the wedge 23 are brought into contact with the pair of inclined surfaces 24, 24 via rollers 27, 27, respectively.

When the parking brake is operated, the wedge 23 is pushed between the pair of piston bodies 2 by pushing the rod 26 downward in FIG.
The interval between the piston bodies 2, 2 is widened. At the time of braking during normal running, pressure oil is fed into the cylinder body 1 through an oil supply port (not shown). If the lining of the brake shoe is worn,
7, the adjusting cylinder 6 is rotated, and the amount of protrusion of the adjusting bolt 8 from the adjusting cylinder 6 is increased.

[0025]

By the way, the conventional brake cylinder with an automatic clearance adjusting device constructed and operated as described above is composed of the piston bodies 2 and
2 cannot always be sufficiently secured.

That is, the stroke amount of each of the piston bodies 2, 2 is limited to a range in which the sleeve 18 and the ratchet pin 17 can be displaced inside the elongated holes 15 formed on the respective side surfaces. On the other hand, semicircular portions 15a, 15a are inevitably formed at both front and rear ends (left and right ends in FIG. 9) of the elongated hole 15 as shown in FIG. On the other hand, the curvatures of the front and rear sides of the sleeve 18 and the ratchet pin 17 are the same as those of the semi-circular portions 15a,
It is inevitable that the curvature becomes considerably larger than the curvature of 15a. This is because the ratchet pin 17 originally having a circular cross section is flattened on both side surfaces so that the tip of the ratchet pin 17 is displaced inside the elongated hole 15 in the longitudinal direction of the elongated hole 15. This is because it is necessary to disable rotation inside the long hole 15.

However, as described above, the sleeve 18 and the ratchet pin 17 having the relatively large curvatures at the front and rear sides are formed by the semicircular portions 15a, 15a of the long hole 15.
You can't get inside. Therefore, the sleeve 18
In addition, the stroke amount l in which the ratchet pin 17 can move inside the long hole 15 is considerably shorter than the length L of the long hole 15. The amount by which each of the piston bodies 2 protrudes from the cylinder body 1 to displace the brake shoe is:
Since the stroke amount l is limited, it is not preferable that the stroke amount l is limited.

In particular, when a large gap exists between the outer peripheral surface of the lining and the inner peripheral surface of the drum, for example, immediately after replacement of the brake shoe, pressure oil is fed into the cylinder body 1;
When each piston body 2 is largely displaced, the sleeve 18 and the ratchet pin 17
Of the ratchet pin 17
May be deformed.

The brake cylinder with an automatic clearance adjusting device according to the present invention has been devised in view of the above-mentioned circumstances.

[0030]

Each of the brake cylinders with an automatic clearance adjusting device according to the present invention has a cylindrical cylinder body having at least one open end, similarly to the above-mentioned conventional brake cylinder with an automatic clearance adjusting device. Inside the cylinder body, a bottomed cylindrical piston body fitted with an opening oil-tight with the opening facing the outside of the cylinder body, and formed on the outer peripheral surface of the piston body over the entire circumference thereof. A locking concave groove, which is mounted in the locking concave groove, the outer peripheral edge of which is slidably contacted with the inner peripheral surface of the cylinder main body, whereby the outer peripheral surface of the piston main body and the inner peripheral surface of the cylinder main body are A packing for maintaining oil tightness between the cylinder body and an oil supply port provided in a part of the cylinder body for sending pressure oil into the cylinder body and pushing the piston body out of the cylinder body;
A circular hole having one end opened at the center of the outer end surface of the piston body, an adjusting cylinder rotatably mounted inside the circular hole and having a female screw formed on an inner peripheral surface thereof, and an inner peripheral surface of the adjusting cylinder. By screwing into the female screw of the above, the tip protruding from the outer end of the adjusting cylinder is engaged with the end of the brake shoe, so that the adjusting bolt is made non-rotatable and the outer peripheral surface of the adjusting cylinder. A first ratchet tooth provided in a state inclined with respect to the axial direction in the circumferential direction, and an elongated hole in the axial direction provided in the piston body in a state aligned with the first ratchet tooth. A guide hole provided in a part of the cylinder main body, which is aligned with the elongated hole, in a radial direction of the cylinder main body; Part into the above-mentioned slot, loosen the second ratchet tooth A ratchet pin is freely serial first ratchet teeth meshing comprises a distal end face of the ratchet pins from the spring to press toward the first ratchet teeth,
By supplying and discharging pressurized oil into and from the cylinder body through the oil supply port, when the piston body is moved in and out of the cylinder body, the adjusting cylinder is adjusted based on engagement and disengagement of the first and second ratchet teeth. Rotate, and the directions of the first and second ratchet teeth and the female screw are determined so that the amount of protrusion of the adjustment bolt from the adjustment cylinder increases.

Further, in the brake cylinder with an automatic clearance adjusting device according to the first aspect, the long hole is formed in a long U-shaped notch shape which opens on the inner end surface side of the piston body. Wherein the locking concave groove is formed between a deep end of the long hole and an outer end surface of the piston body.

Further, in the brake cylinder with the automatic clearance adjusting device according to the present invention, the adjusting cylinder is disposed inside the circular hole so as to be displaceable in the axial direction, and is provided on the outer peripheral surface of the adjusting cylinder. It is characterized in that it is mounted in a state where oil tightness between the circular hole and the inner peripheral surface thereof is maintained, and the inner end of the circular hole is communicated with the inside of the cylinder body.

[0033]

The brake cylinder with the automatic clearance adjusting device according to the present invention having the above-described structure operates when the brake shoe is pressed against a member rotating together with the wheel during braking, and the lining wears. The effect of preventing the gap between the surface of the lining and the surface of the rotating member from becoming too large is the same as that of the above-described conventional brake cylinder with an automatic gap adjusting device.

In particular, in the case of the brake cylinder with the automatic clearance adjusting device according to the present invention, the brake shoe can be largely displaced.

That is, in the case of the invention described in claim 1,
Since the long hole into which the tip of the ratchet pin fits is formed in the shape of a long U-shaped notch that opens toward the inner end surface side of the piston body, the piston body has moved toward the opening of the cylinder body. In this case, the tip of the ratchet pin does not interfere with the end of the long hole. Therefore, it is possible to increase the displacement of the piston body within a range in which the tip of the ratchet pin does not come out of the inside of the elongated hole.

Further, in the case of the invention described in claim 2, after the piston main body cannot be displaced with respect to the cylinder main body, the adjustment provided inside the circular hole provided in the piston main body. The cylinder is displaced in the axial direction, so that the brake shoe whose end is abutted against the adjustment cylinder via the adjustment bolt can be largely displaced.

[0037]

1 and 2 show a first embodiment of the present invention corresponding to the invention described in claim 1. FIG. The feature of the present invention is that the displacement amount of the piston main body 2 with respect to the cylinder main body 1 is increased, and other configurations and operations are the same as those of the above-described conventional brake cylinder with an automatic clearance adjusting device. The duplicate description will be omitted, and only the features of the present invention will be described below.

A long hole 28 is formed in the side surface of the cylindrical piston body 2 in the axial direction of the piston body 2 (the left-right direction in FIGS. 1 and 2). This long hole 28
Are the long holes 1 in the conventional structure (see FIGS. 6, 8 and 9).
As shown in FIG. 5, both ends in the longitudinal direction are not closed, but are formed in a long U-shaped notch shape that opens on the inner end surface side (the right end surface side in FIGS. 1 and 2) of the piston body 2. I have.

In order to mount a packing 3 for maintaining oil tightness between the outer peripheral surface of the piston main body 2 and the inner peripheral surface of the cylinder main body 1, a lock formed on the outer peripheral surface of the piston main body 2 is provided. A concave groove 29 is formed between the deep end of the long hole 28 and the outer end surface (the left end surface in FIGS. 1 and 2) of the piston body 2.

A guide hole 1 is formed in a side surface of the cylinder body 1 so as to extend in a radial direction of the cylinder body 1.
The tip of the ratchet pin 17 fitted to be displaceable in the radial direction is fitted inside the elongated hole 28, and the distal end face of the ratchet pin 17 (FIG. 1) is compressed by the compression spring 21. 2) is pressed against the outer peripheral surface of the sleeve 10 which is non-rotatably fitted to the adjustment cylinder 6.

A ridge 30 is provided on the outer peripheral surface of the intermediate portion of the adjusting cylinder 6.
The adjusting cylinder 6 is formed by engaging the ridge 30 with the step 31 on the inner peripheral surface of the piston body 2.
From the outside end face side opening. or,
A lid plate 32 is fixed inside the inner end opening of the piston main body 2, and the lid plate 32 prevents the adjusting cylinder 6 from coming out of the inner end surface side opening of the piston main body 2. Therefore, the adjusting cylinder 6 is mounted inside the piston main body 2 so as to be rotatable only.

In the case of the brake cylinder with the automatic clearance adjusting device of the present invention configured as described above, the piston body 2
The ratchet pin 17 formed in the axial direction is formed into a long U-shaped cutout opening at the inner end surface side of the piston body 2 where the tip end of the ratchet pin 17 fits. Even when the piston body 2 is moved toward the opening of the cylinder body 1 by sending the pressure oil into the cylinder body 1, the tip of the ratchet pin 17 and the end of the elongated hole 28 are separated. There is no interference.

Accordingly, the displacement of the piston body 2 can be increased within a range in which the tip of the ratchet pin 17 does not come out of the long hole 28.

Next, FIG. 3 shows a second embodiment of the present invention in which the invention described in claim 1 and the invention described in claim 2 are combined.

In the case of this embodiment, the ridges 30 on the outer peripheral surface of the adjusting cylinder 6, the step 31 on the inner peripheral surface of the piston body 2, and the lid plate 32 on the inner end surface (FIGS. 2) is omitted. Therefore, in the case of the present embodiment, the adjusting cylinder 6 fitted in the circular hole 5 of the piston main body 2 can be displaced with respect to the piston main body 2 in the axial direction (the left-right direction in FIG. 3). Become.

With this configuration, in the case of this embodiment, the displacement of the piston body 2 itself can be increased without interference between the tip of the ratchet pin 17 and the end of the elongated hole 28. In addition, after the piston main body 2 cannot be displaced with respect to the cylinder main body 1, that is, when the piston main body 2 is further displaced, the piston main body 2
Since the packing 3 on the outer peripheral surface is exposed outside the cylinder body 1, after the displacement of the piston body 2 is restricted by a stopper mechanism (not shown), the adjustment is performed by the pressure oil sent into the cylinder body 1. The cylinder 6 is displaced in the axial direction so as to be pushed out of the circular hole 5.

As a result, it is possible to greatly displace the brake shoe whose end is abutted against the adjusting cylinder 6 via the adjusting bolt 8 screwed to the center of the adjusting cylinder 6.

FIGS. 4 and 5 show a third embodiment of the present invention corresponding to the invention described in claim 2. FIG.

In this embodiment, the adjusting cylinder 6 is fitted inside the circular hole 5 of the piston body 2 so as to be freely displaceable in the axial direction, and the through hole 33 formed in the piston body 2 is provided.
The pressure oil can be freely fed into the recess of the circular hole 5 through the hole. An inclined surface 24 is formed on the inner end surface of the piston body 2, and the inclined surface 24 and the wedge 23 are in contact with each other via a roller 27. The elongated hole 15 into which the tip end of the ratchet pin 17 is fitted is not a long U-shaped notched shape as in the first and second embodiments, but both ends as shown in FIG. The part is closed.

In the case of this embodiment constructed as described above, the stroke amount of the piston body 2 itself is not large as compared with the conventional structure, but the piston body 2 can be displaced with respect to the cylinder body 1. After disappearing, the adjusting cylinder 6 is axially displaced by the pressure oil sent into the cylinder body 1 so as to be pushed out of the circular hole 5, and is screwed into the center of the adjusting cylinder 6. It is possible to greatly displace the brake shoe whose end is abutted against the adjusting cylinder 6 via the adjusted adjusting bolt 8.

In the case of this embodiment, when braking is performed in a state where the gap between the outer peripheral surface of the brake shoe lining and the inner peripheral surface of the drum is large, the tip of the ratchet pin 17 and the end of the long hole 15 However, in this state, the adjusting cylinder 6 protrudes from the inside of the piston main body 2, and the adjusting cylinder 6 projects between the brake shoe and the piston main body 2. Therefore, at the tip of the ratchet pin 17,
A large force is not applied to deform the ratchet pin 17.

[0052]

The brake cylinder with the automatic clearance adjusting device according to the present invention is constructed and operates as described above. Therefore, the displacement amount of the adjusting cylinder for pressing the brake shoe via the adjusting bolt is ensured, so that the drum can be used. The lining of the brake shoe can be sufficiently pressed against the inner peripheral surface.

Further, since no large force is applied to the tip of the ratchet pin based on the interference between the tip of the ratchet pin and the end of the long hole, the ratchet pin is not deformed, and the automatic clearance is not changed. The reliability and durability of the adjustment mechanism are improved.

Although the above description has focused on the drum brake, the present invention can also be applied to a brake cylinder with an automatic clearance adjusting device for a disc brake.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional view showing a first embodiment of the present invention in a non-braking state.

FIG. 2 is a partial cross-sectional view similarly showing a state during braking.

FIG. 3 is a partial cross-sectional view showing the second embodiment in a non-braking state.

FIG. 4 is a partial cross-sectional view showing the third embodiment in a non-braking state.

FIG. 5 is a partial cross-sectional view similarly showing a state during braking.

FIG. 6 is a front view showing a first example of a conventional brake cylinder with an automatic clearance adjusting device, partially cut away;

FIG. 7 is a view as viewed from below in FIG. 6;

FIG. 8 is a sectional view showing a second example of a conventional brake cylinder with an automatic clearance adjusting device.

FIG. 9 is a sectional view taken along line AA of FIG. 8;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cylinder main body 2 Piston main body 3 Packing 4 Oil supply port 5 Circular hole 6 Adjustment cylinder 7 Female screw 8 Adjustment bolt 9 Engagement recess 10 Sleeve 11 Engagement protrusion 12 Engagement groove 13 First ratchet tooth 14 Compression spring 15 Long hole 15a Half Arc portion 16 Guide hole 17 Ratchet pin 18 Sleeve 19 Second ratchet tooth 20 Lid 21 Compression spring 22 Flange 23 Wedge 24 Inclined surface 25 Secondary cylinder portion 26 Rod 27 Roller 28 Long hole 29 Locking groove 30 Step 31 Part 32 Cover plate 33 Through hole

Claims (2)

(57) [Scope of request for utility model registration] 1. A cylindrical cylinder body having at least one end opened, a bottomed cylindrical piston body fitted inside the cylinder body with an opening oil-tight with an opening directed to the outside of the cylinder body. A locking groove is formed on the outer peripheral surface of the piston body over the entire circumference thereof, and is mounted in the locking groove, and its outer peripheral edge is slidably contacted with the inner peripheral surface of the cylinder body. In order to maintain oil tightness between the outer peripheral surface of the piston main body and the inner peripheral surface of the cylinder main body, and to send pressure oil into the cylinder main body to push out the piston main body from the cylinder main body, An oil supply port provided in a part of the cylinder body, a circular hole having one end opened at the center of the outer end surface of the piston body, and a female screw is rotatably mounted inside the circular hole and has an inner peripheral surface. And the inner circumference of this adjustment cylinder An adjusting bolt that is screwed into the female screw of the surface and that is engaged with the end of the brake shoe so that the tip protruding from the outer end of the adjusting cylinder is disabled to rotate, and the outer peripheral surface of the adjusting cylinder A first ratchet tooth provided in a state of being inclined with respect to the axial direction in the circumferential direction, and an axially long length provided in the piston body in a state of being aligned with the first ratchet tooth. A hole, a guide hole provided in a part of the cylinder main body which is aligned with the elongated hole, and a guide hole provided in a radial direction of the cylinder main body; A ratchet pin having a distal end portion loosely fitted in the elongated hole and a second ratchet tooth provided on the distal end surface being freely engageable with the first ratchet tooth, and a distal end surface of the ratchet pin pressed toward the first ratchet tooth. And the oil supply port Through it By supplying and discharging pressurized oil into the cylinder body, if allowed to enter and exit the piston body from the cylinder body, the first,
The direction of the first and second ratchet teeth and the female screw is adjusted so that the adjusting cylinder rotates based on the engagement and disengagement of the second ratchet teeth and the amount of protrusion of the adjustment bolt from the adjusting cylinder increases. In the brake cylinder with an automatic clearance adjusting device, the long hole is formed in a long U-shaped notch shape that opens on the inner end face side of the piston body, and the locking groove is Is formed between the innermost end of the elongated hole and the outer end surface of the piston body. 2. A cylindrical cylinder body having at least one end opened, a bottomed cylindrical piston body fitted inside the cylinder body with an opening oil-tight with the opening facing the outside of the cylinder body. A locking groove is formed on the outer peripheral surface of the piston body over the entire circumference thereof, and is mounted in the locking groove, and its outer peripheral edge is slidably contacted with the inner peripheral surface of the cylinder body. In order to maintain oil tightness between the outer peripheral surface of the piston main body and the inner peripheral surface of the cylinder main body, and to send pressure oil into the cylinder main body to push out the piston main body from the cylinder main body, An oil supply port provided in a part of the cylinder body, a circular hole having one end opened at the center of the outer end surface of the piston body, and a female screw is rotatably mounted inside the circular hole and has an inner peripheral surface. And the inner circumference of this adjustment cylinder An adjusting bolt which is screwed to the female screw on the surface and which is engaged with the end of the brake shoe, which protrudes from the outer end of the adjusting cylinder, so as not to rotate, and the outer peripheral surface of the adjusting cylinder A first ratchet tooth provided in a state of being inclined with respect to the axial direction in the circumferential direction, and an axially long length provided in the piston body in a state of being aligned with the first ratchet tooth. A hole, a guide hole provided in a part of the cylinder main body, which is aligned with the elongated hole, provided in a radial direction of the cylinder main body; A ratchet pin having a distal end portion loosely fitted in the elongated hole and a second ratchet tooth provided on the distal end surface being freely engageable with the first ratchet tooth, and a distal end surface of the ratchet pin pressed toward the first ratchet tooth. And the oil supply port Through it By supplying and discharging pressurized oil into the cylinder body, if allowed to enter and exit the piston body from the cylinder body, the first,
The direction of the first and second ratchet teeth and the female screw is adjusted so that the adjusting cylinder rotates based on the engagement and disengagement of the second ratchet teeth, and the amount of protrusion of the adjustment bolt from the adjusting cylinder increases. In the brake cylinder with an automatic clearance adjusting device, the adjusting cylinder is disposed inside the circular hole so as to be displaceable in the axial direction, and between the outer peripheral surface of the adjusting cylinder and the inner peripheral surface of the circular hole. A brake cylinder with an automatic clearance adjustment device, wherein the brake cylinder is mounted while maintaining oil tightness, and the inner end of the circular hole is communicated with the cylinder body.