JPH0220464B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a traction type booster for assisting operating force in a brake or clutch device of a vehicle or the like.

[Conventional technology]

Conventionally, this type of device includes a movable body that is movably inserted into the internal space of the main body with a low pressure chamber on one side and a high pressure chamber on the other side, and an input that extends from one side of the movable body to the outside of the main body. a member, an output member extending from the other side of the movable body to the outside of the main body, and disposed between the output member and the input member, the output member being arranged to supply the low pressure chamber and the high pressure chamber in response to input from the input member. A valve device that is opened and closed to generate a differential pressure that biases the movable body toward the one side, and a sealing member disposed on the outer surface of the main body forming a hole through which the input member passes, the sealing member It is known to have an outer circumferential portion fixed to the main body and an inner circumferential portion slidably in close contact with the input member.
(For example, see Japanese Patent Application Laid-Open No. 51-140074.) [Problems to be Solved by the Invention] However, in such devices, when the input member is directly connected to the pedal, if the input member swings during operation, Because the inner circumference of the sealing member deforms significantly relative to the outer circumference as it is pulled toward the input member's swinging side, in some cases the adhesion force to the input member increases to an extreme degree, causing wear and damage to the inner circumference. In some cases, the inner circumferential portion separates from the input member on the opposite side, creating a gap between the two. When something like this happens,
There is a problem in that due to poor sealing between the input member and the main body, pressure leaks from the low pressure chamber to the outside, making it impossible to obtain the desired boosting effect.

The present invention has been made in view of the above-mentioned problems, and prevents excessive deformation of the inner peripheral portion of the sealing member.
The primary purpose is to securely seal between the input member and the main body, and to prevent the desired boosting effect from being lost due to swinging of the input member. By further improving the followability to the input member,
The second purpose is to ensure sealing between the input member and the main body so that the desired boosting effect is not lost.

[Means of the present invention]

In order to achieve the above first object, the present invention has the following features:
The sealing member is provided with a flexible portion that allows displacement of the inner circumferential portion with respect to the outer circumferential portion and connects these two portions, and the input member is provided between the inner circumferential portion and the outer surface of the main body. A sliding plate is provided that slides on the outer surface of the main body in accordance with the swinging motion of the main body.

In addition to the above configuration, in order to achieve the second object, the inner circumferential portion may include a portion located between the sliding plate and the flexible portion so as to be slidable on the outer surface of the main body. A seal portion is provided which abuts and seals the hole, and the seal portion forms a passageway communicating the space defined between the flexible portion and the outer surface of the main body with outside air.

[Effect]

When the input member swings, firstly, the sliding plate follows the input member and slides on the outer surface of the main body, causing deformation of the flexible portion of the sealing member and causing damage to the inner peripheral portion. can be freely displaced with respect to the outer circumference, and the inner circumference is further displaced together with the sliding plate without receiving large frictional resistance from the outer surface of the main body. Excessive deformation that locally changes the adhesion force to the member does not occur. Secondly, the space between the flexible part and the outer surface of the main body is cut off from the low pressure chamber and communicated with the outside air, so that the flexible part is exposed to the differential pressure that occurs between the outside and the low pressure chamber. Because it is easily deformed according to the sliding of the sliding plate without receiving resistance from .

[Effects of the present invention]

In this way, according to the present invention, even if the input member oscillates, it is possible to reliably prevent abrasion damage to the inner circumferential portion and sealing failure due to the occurrence of a gap, thereby achieving the desired boost. The effect can be maintained reliably.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS The traction type booster of the present invention will be explained in detail below based on illustrated examples.

FIG. 1 is a side sectional view of a traction type booster which is an embodiment of the present invention.

In the figure, the towed booster has a total of 1
It has a main body 4 formed by joining together a pot-shaped rear shell 2 and a dish-shaped front shell 3, and a space 5 is formed in the main body 4.

While compressing the outer peripheral bead 10 of the diaphragm 9 between the stepped portion 6 of the rear shell 2 and the flange 7 and cylindrical portion 8 of the front shell 3, the flange 7 of the front shell 3 is engaged with the protrusion 11 of the rear shell 2. In this way, both shells 2 and 3 are connected.

A dish-shaped synthetic resin movable body 14 in which the inner peripheral bead 12 of the diaphragm 9 is fitted into the groove 13 is movably inserted into the space 5, and a negative pressure chamber 15 is provided on the rear shell 2 side, and a negative pressure chamber 15 is provided on the front shell side. Transformer room 1 on 3 side
6 are each divided into sections.

A hub portion 18 that slidably fits into the opening 17 of the front shell 3 is integrally molded in the center of the movable body 14, and the movable body 14 including the hub portion 18
A stepped through hole 19 is bored in the axial direction.

Fitted into the left end of the through hole 19 is an input member 21 which extends through the rear shell 2 and has a clevis 20 screwed onto the outer end of which is connected to a clutch pedal (not shown). A plunger 22 slidably connected to the member 21 is slidably fitted into a medium diameter portion 23 and a small diameter portion 24 on the left side of the through hole 19 .

On the right side of the plunger 22, a relatively long and small diameter stem 25 that extends toward the right is integrally provided, and a head 26 formed at the end of the stem 25 is provided.
A top-shaped casing 27 that can be engaged with the head 26 is slidably fitted into the casing 27 by positioning the head 26 inside the casing 27 through a hole 27a. Between the casing 27 and the main body of the plunger 22, there is a valve spring 30 formed integrally with a conical coil spring portion 28 and a cylindrical coil spring portion 29, and a valve seat 31 formed on the plunger 22 by the valve spring 30. and a valve member 33 made of rubber that is biased to be seated on a valve seat 32 formed on the inner wall of the through hole 19. The right end of the conical coil spring portion 28 of the valve spring 30 is supported by the casing 27, and the left end of this portion 28 is supported by the poppet-shaped valve member 3.
3 is pressed against the stepped portion 34 of the through hole 19. Further, the cylindrical coil spring portion 29 is configured to press the seat portion 35 at the left end of the valve member 33 toward each of the valve seats 31 and 32. 36 and 37 are spring receivers.

Inside the casing 27, in order from the left side, a plate ring 38, a rubber disk 39, and a plate ring 4 are installed.
0 are movably inserted in order, and are prevented from coming out by a plurality of protrusions 41 formed on the right end of the casing 27. One end of the output member 42 is fitted into the casing 27 by passing through each member disposed inside the casing 27, and the output member 42 is fitted into the casing 27.
A head 43 formed at the left end of the plate ring 38 is in spherical contact with the plate ring 38.

A cylindrical portion 45 of a synthetic resin block 44 fitted into the opening of the through hole 19 is movably fitted between the outer periphery of the output member 42 and the plate ring 40 and abuts against the right end surface of the disk 39. This block 44 is supported by a stopper member 46 fitted onto the outer periphery of the end of the hub portion 18. A plate ring-shaped reinforcing member 47 having an inner hole approximately equal to the outer diameter of the output member 42 is integrally arranged in a part of the disk 39 facing the gap between the cylindrical portion 45 and the output member 42. Furthermore, a reinforcing member 4
The outer diameter of 7 is larger than the inner hole at the left end of the cylindrical part 45. In other words, the cylindrical part 45 and the output member 4
The gap between the disc 2 and the disc 39 is sufficiently large so that it does not directly oppose the disc 39. The stopper member 46 has a substantially cup-like shape and includes a bottom plate portion 48 that contacts the block 44 and a cylindrical portion 49 that fits onto the hub portion 18. A large number of claws 51 that can be engaged with the grooves 50
and a large number of claws 52 extending radially outward.

An annular portion 54 of a boot 53 disposed to cover the entire hub portion 18 is fitted into the claw 52 of the stopper member 46, and the boot 53 is held by the stopper member 46. More boots 5
A cup-shaped housing part 55 is integrally formed on the right side of the annular part 54 of No. 3, and a plurality of filters 5 are disposed between the housing part 55 and the stopper member 46.
6 has been inserted. Further, a retractable bellows portion 57 is integrally provided on the left side of the annular portion 54 of the boot 53, and a hub portion 18 is provided at the left end of the bellows portion 57.
A lip-shaped seal portion 5 is fitted with a retainer 58 between the front shell 3 and the opening 17 of the front shell 3.
9 is provided integrally. A sliding ring 61 is disposed on the left side of the seal portion 59 and is prevented from coming off by a retaining ring 60.

The through hole 19 of the hub portion 18 is connected to a large number of grooves 62 formed on the side periphery of the block 44 and the stopper member 46.
A large number of holes 63 are formed in the side circumference of the filter 56 and the boot 53 allows communication with the atmosphere through the holes in the filter 56 and the boot 53. Furthermore, the variable pressure chamber 16 communicates with the space around the plunger 22 through a hole 64 provided along the radial direction of the hub portion 18, and the negative pressure chamber 15 communicates with the space around the plunger 22 through a hole 65 extending along the axial direction. It communicates with the space around the member 33. The negative pressure chamber 15 is connected to a negative pressure source (engine intake manifold, vacuum pump, etc.) through a connector 66 welded near a corner of the rear shell 2.

The movable body 14 is biased to the right by a preload spring 67 arranged between the movable body 14 and the rear shell 2.

A sealing device 69 is disposed between the input member 21 and the rear shell 2 and is located within the recess 68 of the rear shell 2. This sealing device 69 is connected to the input member 2
1, and a rubber sealing member 71 that covers the entire left side of the slide plate 70. combined and integrated. The slide plate 70 is slidable on the bottom surface of the recess 68 and on the input member 21,
The sealing member 71 has a lip part 72 that comes into elastic contact with the input member 21 at its inner peripheral end, and a fixing part 73 with a mandrel that is press-fitted into the corner of the recess 68 at its outer peripheral end. A flexible communication portion 74 is provided between the inner circumferential portion including the lip portion 72 and the fixing portion 73, and a flexible communication portion 74 is provided to enable displacement of the inner circumferential portion. The connecting portion 74 is prevented from coming off, and the outer peripheral side portion of the connecting portion 74 is held down.

Furthermore, a second lip portion 72a that fits on the outer periphery of the slide plate 70 is in close elastic contact with the bottom surface of the recess 68 in a slidable manner, and is also in close elastic contact with the fixing portion 73 and the lip portion 7.
The space 68a between the connecting portion 2a and the connecting portion 2a communicates with the outside air through a small hole 74a formed in the connecting portion 74 and having a relatively small passage surface. In addition, each lip portion 72, 7
A plurality of annular protrusions are formed on 2a, and the seal is achieved by bringing these protrusions into elastic contact.

In addition, in FIG. 1, reference numeral 76 indicates a lip-type sealing member attached to the plunger 22, and reference numeral 77 indicates a plurality of bolts provided for attaching the entire device 1 to the vehicle body. Further, the output member 42 is connected to a clutch wire at a portion (not shown) so as to be interlocked with a clutch operating arm of a clutch device (not shown). 78 is a retaining ring.

The functions of the device 1 will be described below.

Assume that it is currently in an inactive state. Then, the casing 27 is moved to the right by the tension of the portion 28 of the valve spring 30 to the position where it abuts against the block 44, and as a result, the plunger 22 is moved to the right via the stem 25 by the tension of the valve spring 30. It is sitting on the valve member 33 and moving while winning. At this time, since the valve seat 32 and the valve member 33 are separated and the valve seat 31 and the valve member 33 are seated, each chamber 15, 16 is isolated from the atmosphere and mutually As a result, the same negative pressure is introduced into both chambers 15 and 16. Since there is no pressure difference between the two chambers 15 and 16, the movable body 14 moves to the right against the leftward biasing force that the hub portion 18 receives from the atmosphere due to the tension of the preload spring 67, and the front ciel 3
and are in contact with each other with the diaphragm 9 interposed therebetween.

Suppose that in this state, a clutch pedal (not shown) is depressed in order to disconnect the clutch. Then, the input member 21 is pulled to the left, so the plunger 22 and the casing 27
The valve spring 30 overcomes the tension of the portion 28 and moves to the left, and as a result, the valve member 33 seats on the valve seat 32 of the hub portion 18, cutting off communication between the chambers 15 and 16, and the plunger 22 is moved to the left. By further moving, the valve seat 31 separates from the valve member 33 and the atmosphere is supplied to the variable pressure chamber 16.

This causes a pressure difference between the chambers 15 and 16, and this pressure difference causes the movable body 14 to move to the left.

In this way, when the casing 27 moves to the left due to the traction of the input member 21 and the movable body 14 moves to the left due to the differential pressure, the casing 27
Inside, as the casing 27 moves to the left, the protrusion 41 comes into contact with the disk 39 via the plate ring 40, transmitting the input from the input member 21 to the disk 39, and also transmits the input from the input member 21 to the movable body 14. The moving force is transmitted by the cylindrical portion 45 of the block 44 coming into contact with the disk 39.

The leftward acting force transmitted to the disk 39 is transmitted to the output member 42 via the plate ring 38 as a total output. The clutch is disconnected by the output member 42 to which the output is transmitted.

At this time, if the input from the input member 21 is kept at a constant value, in other words, if the input member 21 is moved to the left by the desired distance, the movement of the plunger 22 is also stopped, and this The valve member 33 moves together with the movable body 14 and while seated on the valve seat 32 so as to approach relatively to the stopped plunger 22, and finally the valve member 33 moves toward both valve seats 32.
sit down. As a result, the flow of air into the variable pressure chamber 16 is stopped, so the pressure within the variable pressure chamber 16 becomes constant, and therefore the differential pressure between the two chambers 15 and 16 becomes constant. In this state, the sum of the input from the input member 21 and the moving force of the movable body 14 is in balance with the output. In other words, due to the elastic deformation of the disk 39, a part of the output and the input are balanced, and the rest of the output and the moving force of the movable body 14 are balanced, and furthermore, the input and the moving force are balanced at a predetermined level. Balance in relationships.

That is, the relationship between each acting force is as follows.

Assuming that the disk 39 is deformed uniformly, F ₁ /S ₁ =F ₂ /S _2The sum of the input and moving force corresponds to the output, so F ₃ = (1+S ₁ /S ₂ )F _1However , F ₁ : Input from input member 21 F ₂ : Moving force of movable body 14 F ₃ : Output of output member 42 S ₁ : Elastic contact area between plate ring 40 and disk 39 S ₂ : Cylindrical part 45 and disk 39 In the case of a large input that causes the valve seat 31 and the valve member 33 to remain apart, the moving force of the movable body 14 becomes maximum, so the following relationship is established.

F ₃ =F ₁ +F ₂ max However, F ₂ max: Maximum moving force of the movable body 14 After this state, in order to connect the clutch,
In other words, if we gradually reduce the input F ₁ ,
When the clutch pedal is gradually released, the input member 21 also moves to the right. As a result, the tension in the portion 28 of the valve spring 30 also acts on the valve seat 31 and the valve member 3.
The valve seat 32 and the valve member 33 are separated while the valve member 3 remains seated, the atmosphere in the variable pressure chamber 16 moves toward the negative pressure chamber 15, and the differential pressure between the chambers 15 and 16 gradually decreases.
Finally, it returns to the non-operating position, and the atmosphere in the variable pressure chamber 16 is sufficiently sucked into the negative pressure source, eliminating the differential pressure between the two chambers 15 and 16. At this time, the clutch device changes from a disconnected state to a half-clutch state to a fully connected state.

The effects of the device 1 having the above functions will be described below.

Even when the input member 21 swings in response to depression of the pedal, the slide plate 70 slides on the bottom surface of the recess 68, and this sliding can be easily performed by deforming the communication portion 74 of the sealing member 71. The inner circumferential portion including the lip 72 is connected to the fixing portion 7.
3. Since the input member 21 is displaced without receiving any resistance from the bottom surface of the recess 68 that would cause deformation, it is possible to reliably prevent sealing failures due to swinging of the input member 21.

A pressure difference between the atmosphere and negative pressure acts on the portion between the slide plate 70 and the lip portions 72, 72a of the sealing member 69, and presses these portions to the right. ,72a
The elastic contact force is relatively strong, and sufficient sealing force can be obtained during rocking.

Since a space 68a is formed and this space 68a is communicated with the outside air through the small hole 74a, the communication portion 74 is not subjected to the differential pressure described in the previous section, and the slide plate 7
It is easily deformed in response to the sliding movement of the inner circumferential portion, and is maintained so that the inner circumferential portion can be easily displaced.

Since the slide plate 70 is made of synthetic resin,
The sliding resistance is small and the response to the swinging of the input member 21 is good.

Although the above embodiments have various effects, the present invention can be practiced without being limited to the illustrated examples.

That is, an example in which the small hole 74a is deleted from the illustrated example,
Modifications to the first invention, such as an example in which the lip portion 72a and the small hole 74a are deleted and the fixing portion 73 and the lip portion 72 are sealed, or the shapes of the communication portion 74 and the slide plate 70 are changed. Examples are given, and the specific structure and shape of other parts can of course be changed to various other things, not just the illustrated examples.

[Brief explanation of drawings]

FIG. 1 is a side sectional view of a traction type booster which is an embodiment of the present invention. 1... Traction type booster, 4... Main body, 21...
Input member, 69... Sealing device, 70... Slide plate, 71... Sealing member, 72, 72a... Lip part, 73... Fixing part, 74... Communication part, 74a...
...Small hole.

Claims (1)

[Claims] 1. A movable body movably inserted into the internal space of the main body with a low pressure chamber on one side and a high pressure chamber on the other side;
an input member extending from one side of the movable body to the outside of the main body; an output member extending from the other side of the movable body to the outside of the main body; and an input member disposed between the output member and the input member, a valve device that opens and closes in response to an input to generate a differential pressure in the low pressure chamber and the high pressure chamber that biases the movable body toward the one side; and an outer surface of the main body having a hole through which the input member passes. and a sealing member disposed, the sealing member having an outer circumferential portion fixed to the main body and an inner circumferential portion slidably adhering to the input member. a flexible portion that allows displacement of the inner circumferential portion relative to the outer circumferential portion and connects these two portions; and between the inner circumferential portion and the outer surface of the main body,
A towing type booster comprising a sliding plate that slides on the outer surface of the main body in accordance with the swinging of the input member. 2. A movable body that is movably inserted into the internal space of the main body with a low pressure chamber on one side and a high pressure chamber on the other side;
an input member extending from one side of the movable body to the outside of the main body; an output member extending from the other side of the movable body to the outside of the main body; and an input member disposed between the output member and the input member, a valve device that opens and closes in response to an input to generate a differential pressure in the low pressure chamber and the high pressure chamber that biases the movable body toward the one side; and an outer surface of the main body having a hole through which the input member passes. a sealing member disposed, the sealing member having an outer circumferential portion fixed to the main body, an inner circumferential portion slidably in close contact with the input member, and a displacement of the inner circumferential portion with respect to the outer circumferential portion. a flexible portion that allows these two portions to communicate with each other, and a sliding member that slides on the outer surface of the main body in response to the swinging of the input member, between the inner circumferential portion and the outer surface of the main body. In the towing type booster provided with a moving plate, the inner circumferential portion is located between the sliding plate and the flexible portion and slidably abuts on the outer surface of the main body, and is in contact with the hole. A tractable booster comprising: a seal portion for sealing; the seal portion forms a passageway communicating a space defined between the flexible portion and the outer surface of the main body with outside air;