JPS6025840A - Pneumatic booster - Google Patents

Abstract

PURPOSE:To enlarge the boosting ratio and consequently facilitate the jumping- in adjustment by a structure wherein a first and a second power pistons are independently arranged in a main body in tandem from output side to input side. CONSTITUTION:A pneumatic booster main body 1 is composed of a front shell 2 and a rear shell 8 so as to form spaces respectively therein. A first power piston 4, a center plate 5 serving as a partition wall and a second power piston 6 are independently disposed in an array in tandem from output side to input side in the main body 1 and partition the main body 1 into chambers A, B, C and D successively from output side to input side. A return spring 29 to energize the first power piston rearwards is arranged in the chamber A between the front shell 2 and the first power piston 4 so as to limit the rearward displacement of the piston 4 beyond a predetermined value.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a pressure booster used in brake devices, clutch devices, etc.

(Prior art) Generally speaking, a tandem pressure booster, which utilizes the engine's intake pipe negative pressure to double the pedal force on the flake pedal and transmit it to the mask cylinder, uses a diaphragm as shown in Figure 1. 1', 2' (!:, the diaphragm 1', 2'
The front and rear power pistons 4' and 5' are integrally connected by a cylindrical member 3', and the center grating 6' is disposed between the front and rear power pistons 4' and 5'. Thus, four chambers A are formed in the main body 7' from the output side to the input side (from the left side to the right side in FIG. 1).

B, C, and D, and actuate the rod 8' to create a differential pressure between chambers A, B1, and C, and the thrust generated in the front and rear power pistons 4' and 5' is The signal is transmitted to the output shaft 9'.

In this type of air pressure booster, the front and rear power screws (4r, 5/) are displaced forward (to the left in Figure 1), and as a result receive the thrust of both power screws (4', 5'). The output shaft 9' is used to create a master cylinder, but the resulting reaction force is caused by the output shaft 9', the reaction disk 10' made of an elastic member, the plunger 11', and the rotor]-8'. The reaction force transmitted to the brake pedal at that time is such that the diameter of the flange portion 9a' of the output shaft 9' is D+, and the diameter of the plunger 11 is D+.
'The diameter of the tip (diameter of the left end in Figure 1) is D! given that,
The reaction force J/(Da/Ds of the total thrust Fa applied to the output shaft 9'
It becomes p.

By the way, (D+/D*)* is called the boost ratio,
It is desired that this boost ratio can be set to a large value. However, as mentioned above, the boost ratio is determined by only two component dimensions: the diameter DI of the 72-inch section 9a' of the output shaft 9' and the diameter DI of the tip of the glazer 11'. It was not possible to set the ratio above a certain value.

Further, as shown in FIG. 2, the input/output characteristics of the air pressure booster is such that jump-in FO+ occurs when the human power F1jJ1 is constant. This jump-in FO+ is generally an output generated before the reaction force is transmitted to the rod 8', that is, in a pressure booster as shown in FIG. This is the output required to exceed the clearance δ. Therefore, the jump-in/FO+ is determined only by the clearance δ, and the only way to change the jump-in is to change the clearance δ.

(Object of the Invention) The present invention is intended to solve the above-mentioned problems, and its purpose is to make it possible to set a large boost ratio.

Another object of the present invention is to easily perform january adjustment by means other than changing the clearance between the reaction disk and the granger.

(Structure of the Invention) In order to achieve the above object, the present invention has the following features.
Second power pistons are provided independently in sequence from the output side to the input side within the main body, a tenth piston protruding outward from the main body is attached to the first power piston, and a first power piston is attached to the second power piston. The 20th cylinder that contacts the power piston is movably held, and the 20th cylinder is connected to the second power piston.
This configuration includes a reaction force mechanism that receives a reaction force of zero.

With the above configuration, when setting the boost ratio, xi,
It is now possible to involve the effective force of the diaphragm attached to each of the second power pistons, and the boost ratio is set larger than the conventional boost ratio determined by the diameter of the output shaft and the tip diameter of the glazer. It becomes possible to do so.

In addition, due to the influence of the effective diameter of the diaphragm on the boost ratio,
By changing the effective diameter of the diaphragm, it is possible to adjust the boost ratio.

Furthermore, since the return force of the return spring acts on the reaction force mechanism via the 20th node of the second power piston, it is possible to adjust the jump-in by changing the set load of the return spring. It can be done.

(Example) Embodiments of the present invention will be described below based on the drawings.

In FIG. 3, reference numeral 1 denotes a main body of the air pressure booster, and the main body 1 is configured to have a space inside by a front nonyl 2 and a rear shell 3. Inside the main body 1, a first power piston 4, a center grate 5 as a partition wall, and a second power piston 6 are arranged independently and in sequence from the output side to the human power side (from the left side to the right side in Fig. 3). has been
As a result, chambers A, B, C, and D are sequentially defined in the main body 1 from the output side to the input side.

One end side of the diaphragm 7 is attached to the first power piston 4, and the other end side of the diaphragm 7 is attached to the front shell 2.
and the rear shell 3. A hole 8 is bored in the center of the first power piston 4, and one end of a cylindrical member 9 passes through the hole 8. The cylindrical member 9 has a small diameter portion 9a at one end thereof, and the small diameter portion 9a
A large diameter portion 9b, which is larger in diameter than the small diameter portion 9a, is formed toward the other end. The small diameter portion 9a has its outer circumference l.
The cylindrical member 9 is fixed to the first power piston 4 by screwing a nut 11 into the male thread of the small diameter portion 9a. frJ-shaped part column member 9
An output shaft 10 as a rod is inserted from the output side toward the input side, and the output shaft 10 has a 7272 portion 10a formed approximately in the center in the axial direction of the nut 1.
It is attached to the first power piston 4 by fixing it to the first power piston 1 with a screw 12. The output shaft 10 has a front end (left end in FIG. 3) protruding outside the main body 1,
A piston of a mask cylinder (not shown) is coupled to its front end. On the other hand, the rear end portion (the right end portion in FIG. 3) of the output shaft 10 passes through the small diameter portion 9a and faces the large diameter portion 9b, and the rear end portion is directed toward the second power piston 6. A recess 10b that opens 1" is formed.

Here, the output shaft 10 passes through the inside of the small diameter part 9a in a loosely fitted state, and there is a space between the output shaft 10 and the inner wall of the small diameter part 9a.
A passage 13 communicating with is formed.

Therefore, chamber A and chamber C are in communication. Note that the chamber A is connected to a negative pressure generating section, such as an engine/engine intake pipe (not shown), for example.

The center grate 5 has one end extended to the outer periphery of the large diameter portion 9b of the cylindrical member 9, and a seal member 14 is attached to the one end, and this seal member 14 is airtightly attached to the outer periphery of the large diameter portion 9b. are in contact.

The other end of the center plate 5 is branched, one of which is fixedly held by the asinyl 3, and the other extends parallel to the asiel peripheral wall l toward the second power piston/6. Therefore, the cylindrical member 9 extends in the left-right direction (hereinafter referred to as the front-back direction) in FIG. 3 of the first power piston 4.
It slides airtightly against the center grate 5 with the displacement movement.

One end side of a diaphragm 15 is attached to the second power piston 6, and the other end side of the diaphragm 15 is fitted and held between the inner wall of the other assiel 3 on the one end side of the center plate 5. A passage 16 is formed at the other end to communicate the chamber B with the chamber. The second power piston 6 has its rear end connected to the rear shell 3.
It extends outside the booklet 1 through the rear shell 3, and is maintained in an airtight manner so as to be slidable in the front and rear directions relative to the rear shell 3. The second power piston 6 has a through hole 17 in its axial direction.
A grunger 19 is fitted into a cylinder portion 18 forming a part of the through hole 17 . A spherical end, which is one end of the rod 20, is fitted into the recess 9a of the granger 19, and a brake pedal (not shown) is connected to the other end of the rod 20. 20 constitutes an input shaft. Valve seats 18a and 19b are formed at the rear ends of the cylinder portion 18 and the plunger 9, respectively, and the valve seats 18a +
A poppet pulp 21 is provided in the through hole 17 behind the valve seat 19b, and the poppet pulp 21 is urged by a spring 22 so as to be able to come into contact with and separate from the valve seats 18a and 19b. When the valve is not in operation, the poppet pulp 21 is in contact with the valve seat 191) as shown in the figure, but is spaced apart from the valve seat 18a. The second power piston 6 has one end open to the chamber C and the other end located inside the through hole 17 rearward of the valve seat 18a and forward of the attachment part of the poppet pulp 21 to the second power piston 6. A passage 23 opens to the valve seat 18a, and a passage 24 opens to the chamber at one end and opens into the through hole 17 forward of the valve seat 18a at the other end. Therefore, when not in operation, that is, when the poppet pulp 21 and the valve seat 19'b are in close contact and the poppet pulp 21 and the valve seat 18a are apart, the chamber C and the chamber are connected via the passage 23.24. On the other hand, both chambers C and D are cut off from the atmosphere (the inside of the through hole 17 communicates with the atmosphere at the rear of the poppet pulp 21).

The through hole 17 of the second power piston 6 is formed with an enlarged diameter portion 17a on the chamber C side.
A cylindrical body 25 is fitted into the cylinder portion 18 from above. That is, the cylindrical body 25 includes a small diameter portion 25a and a large diameter portion 25b, and the large diameter portion 25b is formed with a flange portion 25c that expands in diameter toward the outside in the radial direction of the large diameter portion 25b. This cylindrical body 25 has a small diameter portion 25a fitted into the cylinder portion 18 and a large diameter portion 25b fitted into the enlarged diameter portion 17a.
It is attached by pressing and fixing the flange portion 25c to the second power piston 6 via the plate 26. Inside the large diameter portion 25, an action disk 27 formed of an elastic member such as rubber is held, and the reaction disk 27 is a step formed between the large diameter portion 251) and the small assembly portion 25a. 25d, and its position in the rearward direction is restricted from this point. Here, the cylindrical body 25 and the reaction disk 27 constitute a reaction force mechanism.

28 is an M20 rod, and a flange portion 28a is formed at the rear end of the 20th rod 28;
1L is slidably fitted into the large diameter portion 25b. The tip of the 20th node 28 extends in the axial extension direction of the rod 20, and the tip comes into contact with the output shaft 10 in the recess formed at the rear end of the output shaft 10. are in contact with each other.

A return spring 29 is provided between the front shell 2 and the first power piston 4 in the chamber AP3t to bias the first power piston 4 backward.

Note that the rod 20 is urged rearward by a spring 30, and the rod 20 is biased backward by a spring 30. The second power piston 4゜6 returns from the return spring 29ζ (rightward in Fig. 3)
When inactive, the plunger 19 is held in the state shown in the figure, and furthermore, the plunger 19 is prevented from being displaced beyond a predetermined value by a stopper 31.

Next, the operation will be explained.

When a forward thrust is applied to the rod 20 by depressing the brake pedal, the plunger 19 and the poppet valve 21 pushed by the spring 22 move forward inside the stationary second power piston 6. , the poppet valve 21 comes into contact with the valve seat 18a of the cylinder portion 18, and communication between the chamber C and the chamber is cut off.

When the rod 20 is further pressed, the valve seat 19b of the granger 19 is separated from the surface of the poppet valve 19, and at the same time, the atmosphere enters the chamber through the gap and the passage 24. Atmospheric air also enters chamber B through passage 23. This introduction of atmospheric air creates differential pressures between chambers A and B, and between chambers C and chambers, causing the diaphragm 7 and the first power piston 4, the diaphragm 15 and the second power piston 6 to move forward, respectively. Thrust is generated and boost operation is started. At this time, the thrust of the first power piston 4 is directly applied to the output shaft 10.
On the other hand, the thrust of the second (warpist/6) is
The thrust is transmitted to the 20th shaft 28 via the reaction disk 27, and then transmitted to the output shaft 10 attached to the 20th shaft 28 and the first power piston 4.

At this time, chambers A and C are under negative pressure from the negative pressure generating section.

The rearward reaction force is transmitted to the reaction disk 27 via the 20th tube 28. Therefore, the reaction disk 27 is elastically deformed and comes into contact with the plunger 19, and as a result, the reaction force is transmitted to the brake pedal via the plunger 19 and the rod 20.

Second power piston 6 due to forward movement of diaphragm 15
The forward movement of the poppet valve 21 causes the poppet valve 21 to sit on the valve seat 19b of the granger 19 and become stationary, but if the brake pedal is further depressed, the same operation will occur.

When the brake pedal is released, the rearward reaction force from the output shaft IO is transmitted from the granger 19 force to the poppet valve 21, and the poppet valve 21
It is separated from the valve seat 18a of No.8. Therefore, the atmosphere in the chamber B is divided into the passage 16, the chamber D, the passage 24, the cylinder part 18, and the passage 2.
3. The atmosphere in the chamber flows through the chamber C, the cylindrical member 9, the passage 13, and the passage 24, the cylinder part 18, and the passage 23.
, flows out into the chamber A through the passage 13 inside the cylindrical member 9 of the chamber C1. Therefore, as the pressures in chambers B and D decrease, the differential pressures between chambers A and B and between chambers C and C decrease, respectively, and the return spring 29 causes the first. The second power pistons 4 and 6 return to their original positions as shown in Fig.
, D are all kept at the same pressure, and the first. 2nd power piston 4
, 6 are not displaced (see Figure 3).

Here, the input to the rod 20 is Fl, the reaction force of the total thrust applied to the output shaft 10 when differential pressure is generated is Fo, and the reaction force transmitted from the flange portion 28a to the reaction disk 27 is F'0'. , the effective diameters of diacrums 7 and 15 are cl,,d!, respectively. , the diameter of the flange portion 28a is D+, gra/
When the diameter of the tip of the jar 19 is D2, Fo' is approximately (
Fo' is equal to the conventional -V(d,
! +d doubles.

At this time, the boost ratio is the ratio of Fo and yl at that time, so it is approximately ((1, s + tilting force, ') (D,
/D,) Represented by spirit +1. therefore,'("
From the relationship of 10d, s)/d, x
By changing the boosting ratio (D+/Dt)x (see Fig. 1), the boosting ratio (Lm, (b) can be set larger than 4. It acts on the reaction disk 27 via the 20th node 28, and therefore,
By changing the set load of the return spring 29, the jump-in can be adjusted.

Next, other embodiments will be described. In the following embodiments, the same components will be denoted by the same reference numerals, and the explanation thereof will be omitted.

FIG. 4 shows a second embodiment, in which a pressure introduction port 32 is opened to chamber B in place of the passage 16 in the first embodiment, and a pressure introduction port 33 is opened to chamber Di. , the pressure introduction port 32 and the pressure introduction port 33 are connected via a switching valve 34. This switching valve 34 is connected to both chambers B
, D are in communication with each other, and a state in which both chambers B and D are shut off and chamber B is opened to the atmosphere can be arbitrarily switched.

Therefore, when both chambers B and D are communicated with each other by the switching valve 34, if the rod 20 is operated by the brake pedal, the same operation as in the first embodiment is performed.

Furthermore, if both chambers B and D are shut off by the switching valve 34 and chamber B is opened to the atmosphere, the atmosphere will be introduced into chamber B4, and chamber A, which is in communication with the negative pressure generating section, will be introduced. A pressure difference will be generated between the chamber B and the chamber B. Therefore, forward thrust is generated only in the diaphragm 7 and the first power piston 4, and the output shaft 10 operates the mask cylinder.

Since the rear end of the second power piston 6 protrudes outside the main body 1, a pressure difference is generated between the rear end of the second power piston and the chamber C. 2
The power piston 6 is also displaced in conjunction with the first power piston 4, and the brake pedal is also displaced forward.
By observing this state, it can be confirmed that the switching valve 34 is operating.

FIG. 5 shows a third embodiment, in which a return spring 35 is interposed between the center plate 5 and the second power piston 6 in the second embodiment. Therefore, due to the switching valve 31, both chambers B, D) f
: When the chamber B is shut off and opened to the atmosphere, the second power piston/6 is urged rearward by the return spring 35 and will not be displaced. Further, when both chambers B and D are communicated with each other by the switching valve 34, the operation by the brake pedal is as described in the first. This is the same as the second embodiment.

Similarly, the return spring 29 acting on the first power piston 4 may be omitted.

FIG. 6 shows a fourth embodiment. In this fourth embodiment, the inner wall ζ of the rear shell 3 is a support plate 36.
are provided, and rods 37 and 38 sandwiched between the support grate 36 and the asiel 3 pass through the second power piston 6, the first power piston 4, and the front shell 2, respectively, and their tips end in the main body 1. A nut 40 is screwed into a threaded portion 39 that extends outward and is formed at the tip of the rods 37, 38. Each of these rods is 37.38? The inside of the chamber is surrounded by bellows 41 and 42, each of which has a front end fixed to the inner wall of the front shell 2 and a rear end fixed to the first power piston 4. The inside of each bellows 41, 42 communicates with chamber B.

On the other hand, in the chamber C, each rod 37.3B is surrounded by a bellows 43.44, the front end of each bellows 43.44 is fixed to the center plate 5, and the rear end of each of the bellows 43.44 is surrounded by a second bellows 43.44. It is fixed to the power piston 6, and the inside of each bellows 43, 44 communicates with the chamber. A communication hole 45 is formed in the rod 37 in its axial direction, one end of the communication hole 45 opens into the bellows 43, and the other end of the communication hole 45 extends to the tip of the rod 37. . The rod 38 also has a communication hole 4 in its axial direction.
6 is formed, one end of the communication hole 46 opens into the bellows 42, and the other end of the communication hole 46 extends to the tip of the rod 38. The tips of each rod 37 and 38 are connected via a switching valve 34.

In addition, in this embodiment, the first power screw
The entire circumference of the cylindrical member 9 is fixed by graze welding, and the output shaft 10 is connected to the first member using the fastening member 47.
They are each connected to the power piston 4 by caulking. Therefore, the operation by operating the switching valve 34 is the same as in the second embodiment. Thus, this embodiment utilizes existing rods 37, 38, so no additional parts are required.

FIG. 7 shows a fifth embodiment, which is a modification of the fourth embodiment. In this fifth embodiment, the rod 38 is formed with a communicating hole 48 whose distal end opens to the atmosphere and extends in the axial direction from the distal end to the chamber C. 42
Opening 1: J49.5 where the inside and communication hole 48 communicate with each other
0 is formed on the rod 38. The communication hole 48 is the opening 4
The diameter is reduced between 9.50 mm and a stepped portion 51 is therefore formed within the communicating hole 48 . A rod 52 is inserted into the communication hole 48 so as to be movable in the front-rear direction, and a valve body 5 made of an elastic body or the like is attached to the rear end of the rod 52.
3 is installed. Therefore, the stepped portion 51 becomes a valve seat, and the stepped portion 51 and the valve body 53 form an on-off valve 54. A driving device 55 that reciprocates the rod 52 in the front-back direction is connected to the tip of the rod 52, and this driving device 55 is attached to the rod 38 that protrudes outside the main body 1 via a mounting plate 56. . helmet, 57 is rod 52
is a spring that urges the valve body 53 in a direction away from the stepped portion 51. This spring 57 prevents the rod 52 from moving backward due to a pressure difference that may occur before and after the valve body 53. ing. Therefore, in the air pressure booster having such a configuration, when the valve body 53 is separated from the stepped portion 51, the opening 49 and the opening 50 communicate with each other, and the chamber B and the chamber communicate with each other. If the plagier pedal is operated, the same operation as in the second to fourth embodiments will be performed.

Further, when the valve body 53 is brought into contact with the stepped portion 51 by the drive device 55, the atmosphere is introduced only into the chamber B.
A forward thrust is generated only in the first power piston 4, and the output shaft 10 operates the master cylinder.

FIG. 8 shows a sixth embodiment, and this sixth embodiment is as follows:
Pressure inlet 32° 33 switching valve 34 in fg2 embodiment
This is a modification example. In this sixth embodiment, 58
is a rod, and the rear end of this rod 58 is fixed to the inner wall of the asinyl 3, and the tip extends to the outside of the main body 1 through the second power piston 6, center plate 5, first power piston 4, and front shell 2. ing. The rod 58 has
A communication hole 59 is formed in the axial direction from the tip to the rear end, and the portion of the communication hole 59 in the chamber B has a larger diameter than the other portions of the communication hole 59 to form an enlarged diameter portion 60. There is. For this reason, there are stepped portions 61 before and after the enlarged diameter portion 60.
, 62 are respectively formed. This rod 5
18 is also an opening 63 through which the enlarged diameter portion 60 and the chamber B communicate with each other.
At the rear end of the rod 58, an open roller 4 is formed, through which the chamber and the communication hole 59 communicate. A rod 65 is inserted into the communication hole 59 so as to be movable in the front-rear direction, and the rear end of the rod 65 faces the enlarged diameter portion 60 . In the enlarged diameter portion 60, a valve body 66 made of an elastic member or the like is attached to the rear end of the rod 65, and the valve body 66 is loosely fitted in the enlarged diameter portion 60 and can be displaced in the front-rear direction. It has become. Therefore, the stepped portions 61 and 62 each serve as a valve seat, and the stepped portions 61 and 62 and the valve body 66 constitute an on-off valve 67. On the other hand, rod 65
A driving device 55 for reciprocating the rod 65 in the front and back direction is connected to the front end thereof, as in the fifth embodiment. installed. The diaphragm 15, the seal member 68, the diaphragm 7, and the seal member 69 maintain airtightness between the rod 58 and each member 6.5.4.2 through which the rod 58 passes.
7 biases the rod 65 in a direction in which the valve body 66 is always in contact with the stepped portion 62, and prevents the rod 65 from being displaced rearward due to a pressure difference that may occur before and after the valve body 66. ing.

Therefore, in the air pressure booster having such a configuration, when the valve body 66 is brought into contact with the stepped portion 62ζ by the drive device 55, the opening 63 and the opening 64 communicate with each other.
Since the chamber B and the chamber communicate with each other, when the brake pedal is operated, the same operation as in the second embodiment occurs.

Further, when the valve body 66 is brought into contact with the stepped portion 61 by the drive device 55, the atmosphere is introduced only into the chamber B through the communication hole 59 and the opening 63, and the first power piston 4
A forward thrust is generated, and the output shaft 10 operates the mask cylinder.

In this way, this fifth. In the sixth embodiment, since the switching means is built into the main body 1, it is possible to improve the ease of mounting on a vehicle.

Each of the above embodiments provides the following effects. That is, (1) Since the front power piston and the rear power piston are not connected as in the conventional case, a design with sufficient strength is possible.

■ Since (l mushroom V(d4" + at") < 1, the reaction force applied to the reaction force mechanism (the reaction disk 27 and the cylinder body 25 in each embodiment) can be made smaller than before, and the reaction force The strength and durability of the mechanism can be improved.

■ Conventionally, in order to prevent the output shaft 10 from being pulled out from the cylindrical body 25 during transportation, a special pull-out prevention member 12' was required (see Fig. 1), but in this embodiment,
The output shaft 10 is mechanically fixed to the first power piston 4, and the 20th node 28 is enclosed in a recess 10bζ formed at the rear end of the output shaft 10. Therefore, in each embodiment,
Unlike the conventional method, there is no need for a special pull-out prevention member.

Furthermore, in the second to sixth embodiments, it is possible to generate output without operating the brake pedal. As a result, when keeping a vehicle stopped, manual or automatic control can be used, especially as a means of stopping the vehicle on a slope, or as a means of absorbing shock when the vehicle is put into drive range in a vehicle using an automatic transmission. , can be used. In addition, the switching valve 3
4 or the drive device 55 with a function of controlling the introduction of atmospheric air, it is also possible to obtain an appropriate output when the vehicle is stopped.

In the above embodiments, a pressure booster has been described in which chambers A and B, and chambers C and C have a vacuum-atmosphere relationship. It can also be applied to a pressure booster that has a relationship similar to the atmosphere. Furthermore, the reaction force mechanism can be applied to a link machine #l equipped with a reaction lever and a reaction grate, without using the reaction disk 27 made of an elastic member or the like. Furthermore, within the main body 1, a plurality of sets may be provided, each including the first power piston 4 and the second power piston 6.

(Effects of the Invention) As described above, the present invention allows the boosting ratio to be set larger than in the past, and also allows adjustment of the boosting ratio. You can easily adjust the jump-in by changing .

[Brief explanation of drawings]

Fig. 1 is a vertical cross-sectional view showing a pneumatic booster according to the prior art, Fig. 2 is an input/output characteristic diagram showing the human output of the gas booster, and Fig. 3 is a pneumatic pressure booster according to the first embodiment of the present invention. Fig. 4 is a longitudinal sectional view of the pressure booster according to the ig2 embodiment J; Fig. 5 is a longitudinal sectional view of the air pressure booster according to the third embodiment; Fig. 6 is a longitudinal sectional view of the pressure booster according to the third embodiment; FIG. 7 is a longitudinal cross-sectional view of the air pressure booster according to the fifth embodiment; FIG. 8 is a longitudinal cross-sectional view of the air pressure booster according to the sixth embodiment. It is a front view. 1... Air pressure booster main body 4... First power piston 5... Center plate 6... Second power piston 7... Diaphragm 1o... Output shaft 15... Diaphragm 25 ... Cylinder body 27 ... Reaction disk section ... 20th throat CBl cl D ... Chamber Patent applicant TOKICO CO., LTD.

Claims (1)

[Claims] (1) Inside the main body, there is a diaphragm, and a first diaphragm to which the diaphragm is attached. the second power piston and the first power piston; In the air pressure booster in which four chambers are defined from the output side to the input side by a partition wall arranged between the second power pistons b, the first. A second power piston is provided in the main body sequentially and independently from the output side toward the input end, a No. 1 rod protruding toward the outside of the main body is attached to the first power piston, and a second power piston is attached to the second power piston. , an air pressure multiplier characterized in that a 20th point that contacts the first power piston is movably held, and a reaction force mechanism for receiving the reaction force of the 20th point is provided on the second power piston. power device.