WO2020129586A1

WO2020129586A1 - Atmospheric booster device

Info

Publication number: WO2020129586A1
Application number: PCT/JP2019/046972
Authority: WO
Inventors: 啓一齋脇
Original assignee: 日立オートモティブシステムズ株式会社
Priority date: 2018-12-19
Filing date: 2019-12-02
Publication date: 2020-06-25
Also published as: CN113165625A; JPWO2020129586A1; JP7019076B2

Abstract

This atmospheric booster device has a connection part formed so as to connect a constant pressure chamber with a thick part storage chamber which stores a thick part in a state where a power piston advances and a part of a diaphragm abuts against the inner peripheral surface of a front shell. Thus, in a step for detecting airtightness leakage, a folding part or the like of the diaphragm is bitten-in during assembling of the atmospheric booster device even in the state where the power piston advances and a part of the diaphragm abuts against the inner peripheral surface of the front shell. If the airtight state of the constant pressure chamber is not maintained, a route which enables the constant pressure chamber to be connected with the outside of a housing via the thick part storage chamber is secured. Thus, detection of airtightness leakage can be ensured. As a result, the detection accuracy of the airtightness leakage can be improved, and reliability can be improved.

Description

Pneumatic booster

The present invention relates to a pneumatic booster.

As a pneumatic booster, a constant pressure chamber and a variable pressure chamber are defined by a power piston in a housing having at least two shells, and a plunger arranged in a valve body connected to the power piston is moved by an input rod. As a result, the valve device is opened and working gas (atmospheric pressure) is introduced into the variable pressure chamber to generate a pressure difference between the constant pressure chamber where the engine negative pressure is introduced and the variable pressure chamber. There is a structure in which a thrust force generated in a piston is caused to act on an output rod via a reaction member, and a part of an output reaction force acting on the reaction member from the output rod is transmitted to an input rod via a plunger. For example, Patent Document 1 discloses a pneumatic booster having such a structure, in which a circumferential direction regulating portion for positioning the shell in the circumferential direction is formed to facilitate positioning of the shell. There is.

Further, FIG. 7 shows a cross section around the outer peripheral portion of the power piston 100 of the pneumatic booster having the above-described structure. As shown in FIG. 7, the power piston 100 that defines the inside of the housing 102 into a constant pressure chamber 104 and a variable pressure chamber 106 has a diaphragm 108 having a thick portion 110 at the outer edge, and the thickness of the diaphragm 108 is increased. By accommodating the part 110 between the outer peripheral part of the shell 112 and the outer peripheral part of the shell 114, the constant pressure chamber 104 and the variable pressure chamber 106 are sealed from the outside of the housing 102 to be airtight. Note that FIG. 7 shows a state in which a pressure difference is generated between the constant pressure chamber 104 and the variable pressure chamber 106 and the power piston 100 is advanced to the left side in FIG. 7.

Japanese Patent Laid-Open No. 2018-127090

By the way, at the time of assembling the pneumatic booster as described above, the folded portion 108a of the diaphragm 108 of the power piston 100 or the like is caught, and there is a problem that negative pressure leaks from that portion. Such a defect is an event to be detected in the airtight leak detection step of actually generating a pressure difference between the constant pressure chamber 104 and the variable pressure chamber 106 to check the airtight leak after the pneumatic booster is assembled. Is. However, when a pressure difference is generated between the constant pressure chamber 104 and the variable pressure chamber 106, as shown in FIG. 7, the power piston 100 advances and a part of the folded portion 108a of the diaphragm 108 influences the pressure difference. Since it is pulled by and comes into contact with the inner peripheral surface of the shell 112, the constant pressure chamber 104 becomes airtight even if the diaphragm 108 is caught. As described above, the airtightness is prevented by an unintended method, and there is a problem that the airtightness leak detection step cannot detect the leak.

The object of the present invention is to improve the detection accuracy of the airtight leak of the pneumatic booster and improve the reliability.

One embodiment of the present invention includes at least two shells and a power piston disposed between the two shells to define two chambers and having a diaphragm, the wall thickness of which constitutes an outer edge of the diaphragm. Is a pneumatic booster that is housed between the outer peripheries of the two shells and seals the two chambers, wherein the power piston advances to cause a portion of the diaphragm to One of the two chambers formed by the shell disposed on the forward side and the power piston in a state of being in contact with the inner peripheral surface of the shell disposed on the forward side of the shell; It is characterized in that a communication portion is formed for communicating with the thick portion accommodation chamber in which the thick portion is accommodated.

According to the embodiment of the present invention, it is possible to improve the detection accuracy of the airtight leak of the pneumatic booster and improve the reliability.

It is sectional drawing which shows the whole structure of the pneumatic booster which concerns on the 1st Embodiment of this invention. FIG. 2 is a front view of a single diaphragm of the pneumatic booster of FIG. 1. It is sectional drawing which shows the thick part periphery of the diaphragm of the pneumatic booster of FIG. 1 in the state which the front power piston advanced. It is a front view of a single diaphragm of a pneumatic booster according to a second embodiment of the present invention. It is sectional drawing which shows the thick part periphery of the diaphragm in the state which the power piston advanced of the pneumatic booster which concerns on the 3rd Embodiment of this invention. It is sectional drawing which shows the thick part periphery of the diaphragm of the pneumatic booster which concerns on the 4th Embodiment of this invention in the state which the power piston advanced. FIG. 11 is a cross-sectional view showing the vicinity of the thick portion of the diaphragm of the conventional pneumatic booster when the power piston has advanced.

Embodiments will be described below with reference to the drawings. 1 to 6, the common parts are denoted by the same reference numerals, and in FIGS. 1, 3, 5, and 6, the left side of each figure is the front side (front side), The right side is shown as the rear side (rear side).
FIG. 1 schematically shows a configuration of a pneumatic booster 50 according to a first embodiment of the present invention. As shown, the pneumatic booster 50 according to the first embodiment of the present invention is of a tandem type including two

power pistons

7 and 8, and includes a front shell 1 and a rear shell 2. The inside of the housing 3 is divided into two chambers on the front side and the rear side by the center shell 4.

Furthermore, the front chamber is divided into a constant pressure chamber 9 and a variable pressure chamber 11 by a power piston 7 equipped with a diaphragm 5. On the other hand, the rear chamber is partitioned into a constant pressure chamber 10 and a variable pressure chamber 12 by a power piston 8 having a diaphragm 6. Each

power piston

7, 8 has a structure supported by the valve body 13. Further, the thick portion 70 formed on the outer edge of the diaphragm 5 of the power piston 7 is accommodated in the annular thick portion accommodation chamber 72 formed between the outer peripheral portion of the front shell 1 and the outer peripheral portion of the center shell 4. Thus, the constant pressure chamber 9 and the variable pressure chamber 11 are sealed from the outside of the housing 3 to be airtight (see also FIG. 3). Similarly, the thick portion 74 formed on the outer edge of the diaphragm 6 of the power piston 8 is accommodated in the annular thick portion accommodation chamber 76 formed between the outer peripheral portion of the center shell 4 and the outer peripheral portion of the rear shell 2. Thus, the constant pressure chamber 10 and the variable pressure chamber 12 are sealed from the outside of the housing 3 to be airtight.

The valve body 13 is slidably and slidably inserted into the center shell 4 and the rear shell 2, and the rear end portion extends to the outside of the housing 3. The rear shell 2 has a small-diameter cylindrical portion 2a in which the valve body 13 is inserted, and a dust boot 14 is attached to the small-diameter cylindrical portion 2a. The dust boot 14 covers the hollow shaft portion 13b of the valve body 13 extending from the housing 3. The valve body 13 includes a cup-shaped main body portion 13a and a hollow shaft portion 13b, which are connected to each other. The main body portion 13a serves as a sliding portion for the center shell 4, and the hollow shaft portion 13b for the rear shell 2. Each is configured as a sliding portion. Further, a substantially cylindrical hollow boss portion 13c is formed on the cup-shaped bottom portion of the main body portion 13a. In the main body portion 13a of the valve body 13, two

constant pressure chambers

9 and 10 are communicated with each other, and each

constant pressure chamber

9 and 10 is connected to a valve device 22 provided in the hollow shaft portion 13b.

Passages

15a and 15b are provided. Further, the main body portion 13a of the valve body 13 is provided with a first atmosphere passage 16 that connects the rear pressure changing chamber 12 to the valve device 22 in the hollow shaft portion 13b.

On the other hand, in the constant pressure chamber 10 on the rear side, a plurality of (two in the present embodiment) communication pipes 18 having a cylindrical shape are arranged. A second atmosphere passage 17 that connects the front side with the variable pressure chamber 11 is provided. Further, one end of each of the communication pipes 18 is press-fitted and fixed to the center shell 4, and the other end thereof is hermetically and slidably inserted into the power piston 8 on the rear side to be close to the rear shell 2. It has been extended to the part. A penetrating rod 41 is inserted into each of the communication pipes 18 so as to extend through the front shell 1 and the rear shell 2 in an airtight manner and the power piston 7 on the front side in an airtight manner.

Stud bolts

42 and 43 are integrally provided at both ends of the penetrating rod 41. The

stud bolts

42 and 43 are arranged upright on the rear surface of the rear shell 2 and the front surface of the front shell 1. There is. The through rod 41 and the

stud bolts

42 and 43 are provided at two intervals of 180 degrees in the circumferential direction, but the rear shell 2 and the front shell 1 are different in 90 degree phase from these stud bolts. Two general-purpose stud bolts 44 are erected at the position. On the other hand, for example, an engine negative pressure is introduced into the front side constant pressure chamber 9 through a pipe joint 19 provided in the front shell 1, and this negative pressure is transmitted through the

negative pressure passages

15a and 15b to the rear side. It is also introduced into the constant pressure chamber 10.

The valve device 22 interlocks with the input rod 24 as an input shaft that moves forward and backward with respect to the front shell 1 and the rear shell 2, and switches the

variable pressure chambers

11 and 12 to communicate with the

constant pressure chambers

9 and 10 or the outside air. 25, poppet valve 27, negative pressure valve 29, atmosphere valve 31, and valve spring 32. The plunger 25 is fitted in the hollow inside of the hollow boss portion 13c of the valve body 13 so as to be slidable along the axial direction, and is connected to an input rod 24 that works together with a brake pedal (not shown). The rear end of the poppet valve 27 is fixed to the inner peripheral surface of the hollow shaft portion 13b of the valve body 13 by a pressing member 26.

The negative pressure valve 29 is configured such that the outer peripheral edge portion of the front end portion of the poppet valve 27 and the negative pressure valve seat 28 formed on the inner peripheral surface of the hollow shaft portion 13b (hollow boss portion 13c) of the valve body 13 are in contact with each other. It is configured so as to be in contact with and separated from each other. The atmosphere valve 31 is configured such that an inner peripheral edge portion of the front side end portion of the poppet valve 27 and an annular atmosphere valve seat 30 formed at the rear side end portion of the plunger 25 are in contact with and separated from each other. Is. One end of the valve spring 32 is locked to the input rod 24 and constantly urges the poppet valve 27 in the valve closing direction. A return spring 33 is interposed between the pressing member 26 and the input rod 24, and the plunger 25 is operated by the return spring 33 when the plunger 25 is inactive when there is no input from the brake pedal. The state where the atmosphere valve seat 30 is abutted against the inner peripheral edge of the front end of the poppet valve 27 is maintained.

A small diameter portion 60 having a diameter smaller than the inner diameter of the hollow inside of the hollow boss 13c is provided at the tip end portion of the plunger 25. By providing the small diameter portion 60, the tip end surface of the plunger 25 has a small diameter. It is composed of a first tip surface 25a located at the tip of the portion 60 and a second tip surface 25b that extends radially outward from the base end of the small diameter portion 60. The first tip end surface 25a faces the reaction member 35, which will be described later, in contact with it, and the second tip end surface 25b faces the reaction member 64, which will be described later, in contact therewith. Further, in the present embodiment, an annular engaging groove 62 having a predetermined width is formed on the outer peripheral portion on the rear end side of the plunger 25.

A stop key 39 as a retracting end regulating member is inserted from the radial direction of the hollow boss portion 13c, that is, a substantially boundary portion between the main body portion 13a of the valve body 13 and the hollow shaft portion 13b. In this state, one end of the stop key 39 projects into the hollow interior of the hollow boss portion 13c, and the other end projects into the rear-side transformer chamber 12, and one end of the stop key 39 that projects into the hollow interior of the hollow boss portion 13c. The side is engaged with a locking groove 62 provided in the plunger 25 which is one component of the valve device 22. The stop key 39 moves in the axial direction together with the valve body 13 or the input rod 24 to define the retracted ends of the valve body 13 and the input rod 24, and is provided in the small-diameter cylindrical portion 2 a of the rear shell 2. The position in contact with the step portion 40 is the original position. Further, the stop key 39 regulates the relative movement amount between the valve body 13 and the plunger 25.

Further, a counterbore portion 68 is formed at the tip end side opening of the hollow boss portion 13c of the valve body 13, and a reaction member 64 is slidable in the counterbore portion 68 along the axial direction. It is arranged. In the present embodiment, the reaction force member 64 has an annular shape, and one surface 65 faces a reaction member 35, which will be described later, based on the sliding direction of the reaction force member 64, and a part of the other surface 66 is the first side of the plunger 25. 2 is opposed to the tip surface 25b. The remaining portion of the other surface 66 of the reaction force member 64 faces the bearing surface of the counterbore portion 68 of the hollow boss portion 13c so as to be able to come into contact therewith. On the other hand, a reaction member 35 made of an elastic body such as rubber and a large diameter portion 36a of the output rod 36 are arranged at the tip of the hollow boss portion 13c of the valve body 13, and the plunger 25 and the reaction force member 64 are provided. It can come into contact with the back surface of the reaction member 35.

A return spring 37 for returning the valve body 13 to its original position is provided in the cup-shaped main body 13a of the valve body 13 in the constant pressure chamber 9 on the front side. The return spring 37 has one end on the front side on the rear part of the recess 1a of the front shell 1 and the other end on the rear side via a rod holder 38 on the cup bottom (hollow boss) of the main body 13a of the valve body 13. The parts 13c) are arranged so as to be in contact with each other. That is, the rod holder 38 is pressed and fixed to the valve body 13 by the return spring 37.

The rod holder 38 has a cup portion 38a that partially covers the large-diameter portion 36a of the output rod 36 and a collar portion 38b with which the return spring 37 abuts, and the entire rod holder 38 is formed in a hat shape. .. An insertion hole 47 having a diameter larger than the outer diameter of the rod portion 36b, into which the rod portion 36b of the output rod 36 is inserted, is formed in the central portion of the bottom surface portion 38c of the cup portion 38a. The space formed by the cup portion 38a of the rod holder 38 and the output rod 36 serves as a negative pressure passage 15c that connects the constant pressure chamber 9 to the valve device 22, and the insertion hole 47 and the rod portion of the output rod 36. The annular space formed between 36 b and 36 b is a negative pressure passage 15 d that connects the constant pressure chamber 9 to the valve device 22. Further, the annular space formed between the outer periphery of the flange portion 38b of the rod holder 38 and the inner peripheral surface of the main body portion 13a of the valve body 13 serves as a negative pressure passage 15e connecting the constant pressure chamber 9 to the valve device 22. Has become. Here, the negative pressure passage 15 is composed of the respective

negative pressure passages

15a, 15b, 15c, 15d and 15e, and the negative pressure passage 15 constitutes the communication passage in the present embodiment. The valve body 13 is constantly urged by the return spring 37 toward the rear side (return direction). The rod holder 38 also functions as a retainer that prevents the reaction member 35 and the output rod 36 from coming off the valve body 13.

Here, FIG. 2 shows a front view of a single unit of the diaphragm 5 of the power piston 7. As shown in the figure, the folded-back portion 78 of the diaphragm 5 is provided with a plurality of ridges 82 as communication portions 80 at intervals in the circumferential direction of the diaphragm 5. More specifically, these ridges 82 are provided in the region of the diaphragm 5 that comes into contact with the inner peripheral surface 1b of the front shell 1 when the power piston 7 is advanced, as will be described later with reference to FIG. ing. In addition, each of the ridges 82 extends along the area of the diaphragm 5 that comes into contact with the inner peripheral surface 1b of the front shell 1 when the power piston 7 moves forward, in a direction orthogonal to the circumferential direction of the diaphragm 5 (in the plane of FIG. 3). It is formed so as to extend in the parallel direction) and project toward the constant pressure chamber 9 side. Further, as shown in FIG. 2, the diaphragm 5 is provided with two insertion holes 84 into which the penetrating rod 41 is inserted and a mounting hole 86 into which the valve body 13 is mounted. Note that, as shown in FIG. 1, the diaphragm 6 of the power piston 8 is also provided with a plurality of ridges 82 as communication portions 80 at intervals in the circumferential direction of the diaphragm 6. Each of these ridges 82 extends in a direction orthogonal to the circumferential direction of the diaphragm 6 along the region of the diaphragm 6 that comes into contact with the inner peripheral surface of the center shell 4 when the power piston 8 advances, and the constant pressure chamber It is formed so as to project toward the 10 side.

The pneumatic booster 50 is connected to a vehicle body (not shown) and a master cylinder (not shown) via

stud bolts

42, 43 on both ends of the penetrating rod 41 and a general-purpose stud bolt 44. At this time, as shown in FIG. 1, a master cylinder (not shown) is coupled to the recess 1a provided in the front surface of the front shell 1. The cylindrical body 48 of the master cylinder is hermetically inserted into the bottom of the recess 1a and extends into the main body 13a of the valve body 13. Then, the rod portion 36b of the output rod 36 extends into the cylindrical body 48 and is connected to the piston (not shown) of the master cylinder.

Next, the operation of the pneumatic booster 50 according to the first embodiment of the present invention will be described.
With reference to FIG. 1, when the brake pedal is depressed, the plunger 25 moves forward together with the input rod 24, and the atmosphere valve seat 30 at the rear end of the plunger 25 moves to the inner peripheral edge of the front end of the poppet valve 27. The atmosphere valve 31 is opened apart from the part. As a result, the atmosphere flows into the hollow shaft portion 13b of the valve body 13 through the silencer and the filter, and this atmosphere is introduced into the rear-side variable pressure chamber 12 through the first atmosphere passage 16 and the inside of the communication pipe 18. It is also introduced into the front-side variable pressure chamber 11 through the second atmosphere passage 17. As a result, a pressure difference is promptly generated between the front and rear

pressure changing chambers

11 and 12 in which the atmosphere is introduced and the front and rear

constant pressure chambers

9 and 10 in which the negative pressure is introduced. To do. Then, due to this pressure difference, the

power pistons

7 and 8 on the front side and the rear side are propelled, and the thrust force from the tip of the hollow boss portion 13c of the valve body 13 via the reaction member 35 and the output rod 36 to the master cylinder. Is output to the side.

On the other hand, when the depression force on the brake pedal is released, the input rod 24 retracts due to the spring force of the return spring 33, and the plunger 25 also retracts. As a result, the atmosphere valve seat 30 of the plunger 25 comes into contact with the inner peripheral edge of the front side end of the poppet valve 27 to close the atmosphere valve 31, while the poppet valve 27 is lifted by the plunger 25 and the valve The negative pressure valve 29 is opened apart from the negative pressure valve seat 28 of the body 13, and the negative pressure is changed through the

negative pressure passages

15a and 15b and the first and

second atmosphere passages

16 and 17 into the variable pressure chamber 11 on the front side and the rear side. Introduced in 12, the pressure difference is eliminated. Then, with a time lag from the input rod 24, the valve body 13 is retracted by the return spring 37 in the constant pressure chamber 9 on the front side, and the stop key 39 abutting on the valve body 13 is moved to the step portion 40 in the rear shell 2. The negative pressure valve 29 is closed by returning to the abutting original position.

On the other hand, in the pneumatic booster 50 according to the first embodiment of the present invention, as one of the inspection steps after the assembly, for example, when the atmospheric pressure is introduced into the variable pressure chamber 11, the negative pressure is applied to the constant pressure chamber 9. Pressure is applied and an airtight leak detection step is performed to check for airtight leaks. At this time, when a pressure difference is generated between the constant pressure chamber 9 and the variable pressure chamber 11 and the power piston 7 advances, as shown in FIG. 3, among the folded-back portions 78 of the diaphragm 5, the inner peripheral surface of the front shell 1 is formed. The area of the region facing 1b increases, and due to the pressure difference, the region abuts the inner peripheral surface 1b of the front shell 1. Here, in the region of the diaphragm 5 that contacts the inner peripheral surface 1b of the front shell 1, a plurality of ridge portions 82 (communication portions 80) are formed at intervals in the circumferential direction of the diaphragm 5. Therefore, the portions of the diaphragm 5 located on both sides in the extending direction of the protruding portion 82 communicate with the constant pressure chamber 9 and the thick portion accommodation chamber 72 without contacting the inner peripheral surface 1b of the front shell 1. A passage is secured. As a result, when the folded-back portion 78 of the diaphragm 5 or the like is caught during the assembly of the pneumatic booster 50, the constant pressure chamber 9 is provided outside the housing 3 via the passage secured by the protruding portion 82. Airtight leak is detected in communication with.

The same applies to the diaphragm 6 of the power piston 8, and when the power piston 8 advances, the area of the folded portion of the diaphragm 6 facing the inner peripheral surface of the center shell 4 increases, and the pressure difference is further increased. Due to the influence, the region comes into contact with the inner peripheral surface of the center shell 4. However, in the region of the diaphragm 6 that abuts the inner peripheral surface of the center shell 4, since a plurality of protrusions 82 (communication portions 80) are formed at intervals in the circumferential direction of the diaphragm 6, the diaphragm 6 of the diaphragm 6 is formed. The portions of the ridges 82 located on both sides in the extending direction are provided with passages that connect the constant pressure chamber 10 and the thick portion accommodation chamber 76 without contacting the inner peripheral surface of the center shell 4. As a result, if the folded-back portion of the diaphragm 6 or the like is caught at the time of assembling the pneumatic booster 50, the constant pressure chamber 10 is connected to the outside of the housing 3 via the passage secured by the convex strip 82. Communication, airtight leak is detected.

As described above, in the pneumatic booster 50 according to the first embodiment of the present invention, the power piston 7 is generated due to the pressure difference between the two chambers (the constant pressure chamber 9 and the variable pressure chamber 11). In the following state in which the chamber has advanced, a communication portion 80 is formed for communicating between one chamber 9 of the two

chambers

9 and 11 and the thick portion accommodation chamber 72. Specifically, as shown in FIG. 3, in the communication portion 80, the power piston 7 moves forward so that a part of the diaphragm 5 is the inner circumference of the front shell 1 arranged on the forward side of the two

shells

1, 4. The constant pressure chamber 9 formed by the front shell 1 and the power piston 7 and the thick portion accommodating chamber 72 in which the thick portion 70 of the diaphragm 5 is accommodated are communicated with each other while being in contact with the surface 1b. .. Alternatively, as shown in FIG. 1, the communication portion 80 includes the center piston 4 and the power piston 8 in a state where the power piston 8 advances and a part of the diaphragm 6 is in contact with the inner peripheral surface of the center shell 4. The constant pressure chamber 10 formed by the above is communicated with the thick portion accommodating chamber 76 in which the thick portion 74 of the diaphragm 6 is accommodated.

As a result, in the airtight leak detection step performed after the pneumatic booster 50 is assembled, for example, a negative pressure is applied to the

constant pressure chambers

9 and 10 in a state where the atmospheric pressure is introduced into the

variable pressure chambers

11 and 12, and the constant pressure chamber 9 is 10, a pressure difference is generated between the

variable pressure chambers

11 and 12, the

power pistons

7 and 8 move forward, and a part of the

diaphragms

5 and 6 become the inner peripheral surface 1b of the front shell 1 (center shell 4). Even in the abutting state, the

constant pressure chambers

9 and 10 can communicate with the thick-

walled chambers

72 and 76. Therefore, if the folded portions of the

diaphragms

5 and 6 are bitten during the assembly of the pneumatic booster 50 and the

constant pressure chambers

9 and 10 are not kept airtight, the airtight leak detecting step described above is performed. In the above, since the path through which the

constant pressure chambers

9 and 10 communicate with the outside of the housing 3 via the thick-

walled chambers

72 and 76 is ensured, the airtight leak can be reliably detected. As a result, the airtight leak detection accuracy of the pneumatic booster 50 can be increased, and the reliability can be improved.

Further, in the pneumatic booster 50 according to the first embodiment of the present invention, as shown in FIG. 2 and FIG. 3, the communication portion 80 causes the diaphragm 5 of the power piston 7 to move forward when the power piston 7 advances. It is a ridge portion 82 formed in a region in contact with the inner peripheral surface 1b of the front shell 1. As can be seen in FIG. 3, the ridge 82 extends along a region where the diaphragm 5 contacts the inner peripheral surface 1b of the front shell 1 in a direction orthogonal to the circumferential direction of the diaphragm 5 (parallel to the paper surface of FIG. 3). (I.e., different directions), and also protrudes toward the constant pressure chamber 9 side. Further, as shown in FIG. 1, the ridge portion 82 as the communicating portion 80 provided on the diaphragm 6 of the power piston 8 on the rear side has the diaphragm 6 and the inner peripheral surface of the center shell 4 when the power piston 8 advances. Along the contacting area, the diaphragm 6 extends in a direction orthogonal to the circumferential direction of the diaphragm 6 (direction parallel to the paper surface of FIG. 1), and projects toward the constant pressure chamber 10 side.

With the above-described configuration, in the airtight leak detecting step, a pressure difference is generated between the

constant pressure chambers

9 and 10 and the

variable pressure chambers

11 and 12, the

power pistons

7 and 8 move forward, and part of the

diaphragms

5 and 6 are moved. Even when the abutting contact with the inner peripheral surface 1b of the front shell 1 (center shell 4), at least the portions of the

diaphragms

5 and 6 located on both sides in the extending direction of the ridge portion 82 of the front shell 1 (center shell 4). It is possible to form a passage that allows the

constant pressure chambers

9 and 10 and the thick-

walled chambers

72 and 76 to communicate with each other without contacting the inner peripheral surface 1b. Therefore, if the folded-back portions of the

diaphragms

5 and 6 are engaged, the airtight leak can be detected more reliably in the airtight leak detection step, and the reliability can be further improved. ..

Next, FIG. 4 shows a front view of a single body of the diaphragm 5 used in the pneumatic booster according to the second embodiment of the present invention. A feature of the diaphragm 5 is that the folded-back portion 78 is provided with a plurality of concave streak portions 88 as communication portions 80 at intervals in the circumferential direction of the diaphragm 5. More specifically, these recessed portions 88 are provided in the region of the diaphragm 5 that comes into contact with the inner peripheral surface 1b of the front shell 1 when the power piston 7 is advanced as shown in FIG. Further, each of the recessed portions 88 extends along the region of the diaphragm 5 that comes into contact with the inner peripheral surface 1b of the front shell 1 when the power piston 7 moves forward, in a direction orthogonal to the circumferential direction of the diaphragm 5 (in the plane of FIG. 3). It is formed so as to extend in the parallel direction) and is recessed toward the variable pressure chamber 11 side. Further, although not shown, in the pneumatic booster according to the second embodiment of the present invention, a plurality of diaphragms 6 of the power piston 8 are provided as communicating portions 80 at intervals in the circumferential direction of the diaphragm 6. The concave streak portion 88 is provided. Each of these ridges 88 extends in the direction orthogonal to the circumferential direction of the diaphragm 6 along the region of the diaphragm 6 that comes into contact with the inner peripheral surface of the center shell 4 when the power piston 8 advances, and the variable pressure chamber It is formed so as to be recessed toward the 12 side.

With the configuration as described above, the pneumatic booster according to the second embodiment of the present invention causes a pressure difference between the

constant pressure chambers

9 and 10 and the

variable pressure chambers

11 and 12 in the airtight leak detection step. Then, even if the

power pistons

7 and 8 move forward and a part of the

diaphragms

5 and 6 come into contact with the inner peripheral surface 1b of the front shell 1 (center shell 4), the inner surface of the recessed line portion 88 is It is possible to form a passage that communicates between the

constant pressure chambers

9 and 10 and the thick

portion storage chambers

72 and 76 without contacting the inner peripheral surface 1b of the center shell 4). Therefore, as in the pneumatic booster 50 according to the first embodiment of the present invention in which the communicating portion 80 is the convex portion 82, the folded portions of the

diaphragms

5 and 6 and the like may be engaged. If so, the airtight leak can be detected more reliably in the airtight leak detection step, and the reliability can be further improved.

Further, FIGS. 5 and 6 illustrate the vicinity of the thick portion 70 of the diaphragm 5 in the state where the power piston 7 is advanced in the pneumatic booster according to the third and fourth embodiments of the present invention. ing. First, in the pneumatic booster according to the third embodiment of the present invention shown in FIG. 5, a region of the inner peripheral surface 1b of the front shell 1 that comes into contact with the folded-back portion 78 of the diaphragm 5 when the power piston 7 advances. A ridge portion 90 is provided as the communication portion 80. The ridge portion 90 extends along the inner peripheral surface 1b of the front shell 1 in a direction orthogonal to the circumferential direction of the front shell 1 (direction parallel to the paper surface of FIG. 5) and faces the constant pressure chamber 9 side. Are formed so as to project. Further, although not shown, the pneumatic booster according to the third embodiment of the present invention is provided on the inner peripheral surface of the center shell 4 in a region where it abuts the folded portion of the diaphragm 6 when the power piston 8 advances. A ridge portion 90 is provided as the communication portion 80. The ridge portion 90 extends along the inner peripheral surface of the center shell 4 in a direction orthogonal to the circumferential direction of the center shell 4 and is formed to project toward the constant pressure chamber 10 side.

Next, in the pneumatic booster according to the fourth embodiment of the present invention shown in FIG. 6, the inner peripheral surface 1b of the front shell 1 comes into contact with the folded-back portion 78 of the diaphragm 5 when the power piston 7 advances. A groove 92 is provided in the area as the communication portion 80. The groove 92 extends along the inner peripheral surface 1b of the front shell 1 in the direction orthogonal to the circumferential direction of the front shell 1 (the direction parallel to the paper surface of FIG. 6) and extends toward the outside of the housing 3. It is formed in a concave shape. Further, although not shown, the pneumatic booster according to the fourth embodiment of the present invention is provided in an area of the inner peripheral surface of the center shell 4 that abuts the folded portion of the diaphragm 6 when the power piston 8 advances. A groove 92 is provided as the communication portion 80. The groove 92 extends along the inner peripheral surface of the center shell 4 in a direction orthogonal to the circumferential direction of the center shell 4, and is formed in a manner recessed toward the outside of the housing 3.

In the pneumatic boosters according to the third and fourth embodiments of the present invention having the above-described configuration, the pressure difference between the

constant pressure chambers

9 and 10 and the

variable pressure chambers

11 and 12 in the airtight leak detection step. Occurs, the

power pistons

7, 8 move forward, and even if a part of the

diaphragms

5, 6 come into contact with the inner peripheral surface 1b of the front shell 1 (center shell 4), at least both sides in the extending direction of the ridge 90 are extended. The diaphragm 5 is not in contact with the inner peripheral surface 1b of the front shell 1 (center shell 4) located on the inner surface of the front shell 1 (center shell 4) or the inner surface of the concave portion 92, and the

constant pressure chambers

9 and 10 and the meat. It is possible to form a passage that communicates with the thick

part accommodation chambers

72 and 76. Therefore, as in the pneumatic boosters according to the first and second embodiments of the present invention, if the folded-back portions of the

diaphragms

5 and 6 are engaged, the airtightness is detected in the airtightness leak detection step. Leakage can be detected more reliably, and reliability can be further improved.

Here, in each of the above-described embodiments, the ridges 82 and 90 and the

ridges

88 and 92 provided on the

diaphragms

5 and 6 and the

shells

1 and 4 as the communication portion 80 are the

diaphragms

5 and 6 and the shell 1. Although it is preferable to arrange them uniformly in the circumferential direction of 4, it may be arranged at any position. Further, the number of the ridges 82, 90 and the

ridges

88, 92 may be plural or one for each of the

diaphragms

5, 6 or the

shells

1, 4. Further, as the communicating portion 80, the convex streak portions 82, 90 and the

concave streak portions

88, 92 may simultaneously exist in one

diaphragm

5, 6 or the

shells

1, 4. In addition, the lengths, widths, heights or depths of the ridges 82 and 90 and the

ridges

88 and 92 are the same as those of the

constant pressure chambers

9 and 10 when the

power pistons

7 and 8 are advanced. The size is set to an appropriate size so that a passage communicating with the

partial accommodation chambers

72 and 76 can be secured.
In each embodiment, the invention is applied to the tandem type pneumatic booster including the two

power pistons

7 and 8, but is naturally applied to the pneumatic booster including one power piston. It is also possible.

As the pneumatic booster 50 based on this embodiment described above, for example, the following modes are conceivable.
The first aspect defines at least two shells (1, 2, 4) and two chambers (9, 10, 11, 12) arranged between the two shells (1, 2, 4). And a power piston (7, 8) having a diaphragm (5, 6), and a thick portion (70, 74) forming an outer edge of the diaphragm (5, 6). A pneumatic booster (50) housed between the outer peripheries of the power pistons (7, 8) for sealing the two chambers (9, 10, 11, 12). ) Moves forward, and a part of the diaphragm (5, 6) becomes the inner peripheral surface (1b) of the shell (1, 4) arranged on the forward side of the two shells (1, 2, 4). One of the two chambers (9, 10, 11, 12) formed by the shells (1, 4) arranged on the forward side and the power piston (7, 8) in the abutting state. A communication portion (80) is formed for communicating between the chambers (9, 10) and the thick portion storage chambers (72, 76) in which the thick portions (70, 74) are stored. ..

A second aspect is the first aspect, wherein the two chambers (9, 10, 11, 12) include a shell (1, 4) arranged on the advance side and the power piston (7, 8). Constant pressure chamber (9, 10) formed by the power piston (7, 8) and the shell (2, 4) disposed on the side opposite to the forward side of the two shells (1, 2, 4). ) And a variable pressure chamber (11, 12) formed by a plunger (25) arranged in a valve body (13) connected to the power piston (7, 8) by an input rod (24). By moving it, the valve device (22) is opened to introduce working gas into the variable pressure chamber (11, 12), and between the constant pressure chamber (9, 10) and the variable pressure chamber (11, 12). A pressure difference is generated, and the thrust force generated in the power piston (7, 8) by the pressure difference is applied to the output rod (36) via the reaction member (35), and the output rod (36) outputs the thrust. A pneumatic booster (50) that transmits a part of the reaction force acting on the reaction member (35) to the input rod (24) via the plunger (25), and the communication section (80) is , A region of the diaphragm (5, 6) that comes into contact with the inner peripheral surface (1b) of the shell (1, 4) arranged on the forward side when the power piston (7, 8) advances, The ridges (82, 90) are formed so as to extend in a direction orthogonal to the circumferential direction of the diaphragms (5, 6) and project toward the constant pressure chambers (9, 10). ..

A third aspect is the second aspect, wherein the ridge (82) is provided on the diaphragm (5, 6).
A 4th aspect is a 2nd aspect. WHEREIN: The said convex-line part (90) is provided in the shell (1, 4) arrange|positioned at the said advance side.

A fifth aspect is the first aspect, wherein the two chambers (9, 10, 11, 12) include a shell (1, 4) arranged on the advance side and the power piston (7, 8). Constant pressure chamber (9, 10) formed by the power piston (7, 8) and the shell (2, 4) disposed on the side opposite to the forward side of the two shells (1, 2, 4). ) And a variable pressure chamber (11, 12) formed by a plunger (25) arranged in a valve body (13) connected to the power piston (7, 8) by an input rod (24). By moving it, the valve device (22) is opened to introduce working gas into the variable pressure chamber (11, 12), and between the constant pressure chamber (9, 10) and the variable pressure chamber (11, 12). A pressure difference is generated, and the thrust force generated in the power piston (7, 8) by the pressure difference is applied to the output rod (36) via the reaction member (35), and the output rod (36) outputs the thrust. A pneumatic booster (50) that transmits a part of the reaction force acting on the reaction member (35) to the input rod (24) via the plunger (25), and the communication section (80) is , A region of the diaphragm (5, 6) that comes into contact with the inner peripheral surface (1b) of the shell (1, 4) arranged on the forward side when the power piston (7, 8) advances, A groove (88, 92) extending along a direction orthogonal to the circumferential direction of the diaphragm (5, 6) and formed to be recessed toward the variable pressure chamber (11, 12). ..

A sixth aspect is the fifth aspect, wherein the recessed portion (88) is provided on the diaphragm (5, 6).
In a seventh aspect according to the fifth aspect, the groove (92) is provided in the shell (1, 4) arranged on the advance side.

It should be noted that the present invention is not limited to the above-described embodiment, and various modifications are included. For example, the above-described embodiments have been described in detail in order to explain the present invention in an easy-to-understand manner, and are not necessarily limited to those having all the configurations described. Further, a part of the configuration of one embodiment can be replaced with the configuration of another embodiment, and the configuration of another embodiment can be added to the configuration of one embodiment. Further, it is possible to add/delete/replace other configurations with respect to a part of the configurations of the respective embodiments.

The present application claims priority based on Japanese Patent Application No. 2018-237558 filed on December 19, 2018. The entire disclosure of Japanese Patent Application No. 2018-237558, filed December 19, 2018, including the specification, claims, drawings, and abstract, is incorporated herein by reference in its entirety.

1: front shell, 1b: inner peripheral surface, 2: rear shell, 4: center shell, 5, 6: diaphragm, 7, 8: power piston, 9, 10: constant pressure chamber, 11, 12: variable pressure chamber, 13: valve Body, 22: valve device, 24: input rod, 25: plunger, 35: reaction member, 36: output rod, 50: pneumatic booster, 70, 74: thick portion, 72, 76: thick portion accommodation Chamber, 78: folded portion, 80: communicating portion, 82, 90: convex strip portion, 88, 92: concave strip portion

Claims

A pneumatic booster, the pneumatic booster comprising:
At least two shells,
A power piston having a diaphragm disposed between the two shells to define two chambers,
A thick portion forming the outer edge of the diaphragm is housed between the outer peripheral portions of the two shells to seal the two chambers,
The power piston is moved forward and a part of the diaphragm is disposed on the forward side of the two chambers in a state of being in contact with an inner peripheral surface of a shell of the two shells disposed on the forward side. And a communicating portion for communicating between one chamber formed by the shell and the power piston and the thick-walled chamber containing the thick-walled portion. Pneumatic booster.
The pneumatic booster according to claim 1,
The two chambers are a constant pressure chamber formed by the shell arranged on the advance side and the power piston, and a shell arranged on the opposite side to the advance side of the two shells and the power piston. Is a transformer room that is formed,
By moving the plunger arranged in the valve body connected to the power piston by the input rod, the valve device is opened to introduce the working gas into the variable pressure chamber, and the constant pressure chamber and the variable pressure chamber are connected. A pressure difference is generated between them, and a thrust force generated in the power piston due to the pressure difference is caused to act on the output rod via the reaction member, and a part of the reaction force acting on the reaction member from the output rod, Is transmitted to the input rod through the plunger,
The communication portion extends in a region of the diaphragm that abuts the inner peripheral surface of the shell disposed on the forward side when the power piston moves forward, and extends in a direction orthogonal to the circumferential direction of the diaphragm along the region. The pneumatic booster is characterized in that it is a ridge portion formed so as to project toward the constant pressure chamber side.
The pneumatic booster according to claim 2,
The pneumatic booster, wherein the ridge portion is provided on the diaphragm.
The pneumatic booster according to claim 2,
The pneumatic booster, wherein the convex portion is provided on the shell arranged on the forward side.
The pneumatic booster according to claim 1,
The two chambers are a constant pressure chamber formed by the shell arranged on the advance side and the power piston, and a shell arranged on the opposite side to the advance side of the two shells and the power piston. Is a transformer room that is formed,
By moving the plunger arranged in the valve body connected to the power piston by the input rod, the valve device is opened to introduce the working gas into the variable pressure chamber, and the constant pressure chamber and the variable pressure chamber are connected. A pressure difference is generated between them, and a thrust force generated in the power piston due to the pressure difference is caused to act on the output rod via the reaction member, and a part of the reaction force acting on the reaction member from the output rod, Is transmitted to the input rod through the plunger,
The communication portion extends in a region of the diaphragm that abuts the inner peripheral surface of the shell disposed on the forward side when the power piston moves forward, and extends in a direction orthogonal to the circumferential direction of the diaphragm along the region. The pneumatic booster, which is a concave streak portion formed to be recessed toward the variable pressure chamber side.
The pneumatic booster according to claim 5,
The pneumatic booster, wherein the recessed portion is provided on the diaphragm.
The pneumatic booster according to claim 5,
The pneumatic booster, wherein the recessed portion is provided in the shell arranged on the forward side.