KR20110136914A - Brake booster - Google Patents

Brake booster Download PDF

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Publication number
KR20110136914A
KR20110136914A KR1020100056829A KR20100056829A KR20110136914A KR 20110136914 A KR20110136914 A KR 20110136914A KR 1020100056829 A KR1020100056829 A KR 1020100056829A KR 20100056829 A KR20100056829 A KR 20100056829A KR 20110136914 A KR20110136914 A KR 20110136914A
Authority
KR
South Korea
Prior art keywords
valve
valve body
poppet valve
input shaft
spring
Prior art date
Application number
KR1020100056829A
Other languages
Korean (ko)
Inventor
김태환
Original Assignee
주식회사 만도
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 주식회사 만도 filed Critical 주식회사 만도
Priority to KR1020100056829A priority Critical patent/KR20110136914A/en
Publication of KR20110136914A publication Critical patent/KR20110136914A/en

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
    • B60T13/00—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems
    • B60T13/10—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems with fluid assistance, drive, or release
    • B60T13/24—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems with fluid assistance, drive, or release the fluid being gaseous
    • B60T13/46—Vacuum systems
    • B60T13/52—Vacuum systems indirect, i.e. vacuum booster units
    • B60T13/567—Vacuum systems indirect, i.e. vacuum booster units characterised by constructional features of the casing or by its strengthening or mounting arrangements
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
    • B60T13/00—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems
    • B60T13/10—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems with fluid assistance, drive, or release
    • B60T13/24—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems with fluid assistance, drive, or release the fluid being gaseous
    • B60T13/46—Vacuum systems
    • B60T13/52—Vacuum systems indirect, i.e. vacuum booster units
    • B60T13/57—Vacuum systems indirect, i.e. vacuum booster units characterised by constructional features of control valves
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
    • B60T13/00—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems
    • B60T13/10—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems with fluid assistance, drive, or release
    • B60T13/24—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems with fluid assistance, drive, or release the fluid being gaseous
    • B60T13/46—Vacuum systems
    • B60T13/52—Vacuum systems indirect, i.e. vacuum booster units
    • B60T13/573—Vacuum systems indirect, i.e. vacuum booster units characterised by reaction devices
    • B60T13/575—Vacuum systems indirect, i.e. vacuum booster units characterised by reaction devices using resilient discs or pads
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
    • F16K7/00—Diaphragm valves or cut-off apparatus, e.g. with a member deformed, but not moved bodily, to close the passage ; Pinch valves
    • F16K7/12—Diaphragm valves or cut-off apparatus, e.g. with a member deformed, but not moved bodily, to close the passage ; Pinch valves with flat, dished, or bowl-shaped diaphragm
    • F16K7/14—Diaphragm valves or cut-off apparatus, e.g. with a member deformed, but not moved bodily, to close the passage ; Pinch valves with flat, dished, or bowl-shaped diaphragm arranged to be deformed against a flat seat

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Transportation (AREA)
  • General Engineering & Computer Science (AREA)
  • Braking Systems And Boosters (AREA)

Abstract

PURPOSE: A brake booster is provided to effectively reduce load at the initial step of a brake operation. CONSTITUTION: A brake booster comprises a casing, a valve body, a plunger(65), an input axis(60), a puppet valve(80), a first valve sheet(91), a second valve sheet(92), a first spring(66), a second spring(67), a hiding member(100), and a communicating room(110). The casing is divided into a constant pressure room and a variable pressure room. The valve body comprises an air intake unit communicating with the air. The valve body comprises a constant pressure path to be able to connect the constant pressure room to the variable pressure room in an open state.

Description

Brake Booster {BRAKE BOOSTER}

The present invention relates to a brake booster, and more particularly, to a brake booster provided to effectively reduce an initial braking load without significantly affecting return performance.

In general, a vehicle brake booster is a device that generates a large braking force with a small force by using a pressure difference between the vacuum and the atmosphere, and a master cylinder assembly (not shown) is coupled to the front shell 1 side, thereby amplifying the amplified force. To allow braking hydraulic pressure to form.

As shown in FIG. 1, a conventional brake booster for a vehicle includes a casing 1 in which a front shell 1a and a rear shell 1b are hermetically coupled to each other, and a positive pressure chamber 2 and a transformer chamber in the casing 1. Diaphragm 4 and power piston 5 partitioned by (3), one end is combined with the diaphragm 4 and power piston (5) and the other end penetrates the rear shell (1b) to control the air inlet It includes a valve body 6, an input shaft (7) interlocked by a brake pedal (not shown) and an output shaft (8) receiving a displacement force in accordance with its operation.

The valve body 6 slides integrally with the diaphragm 4 and the power piston 5, the other end of which consists of an air intake 6a in communication with the atmosphere.

Inside the valve body 6, a constant pressure passage 6b for communicating the constant pressure chamber 2 and the transformer chamber 3, a transformer passage 6c for communicating the atmosphere and the transformer chamber 3, and an end of the input shaft 7 Combined with the plunger 6d for sliding in the axial direction, disposed between the plunger 6d and the output shaft 8, the reaction disk 6e for doubling the applied force, and according to the operation of the input shaft 7 The poppet valve 6f which controls the inflow of air is arrange | positioned.

The poppet valve 6f is provided in the form of a corrugated pipe, and the rear end thereof is firmly fixed to the air intake portion 6a of the valve body 6 through the fixing member 6g, and the front end thereof is the positive pressure passage 6b and the transformer passage 6c. Will be selectively opened and closed. A first valve seat 6h is provided at the inner circumference of the valve body 6 corresponding to the front end of the poppet valve 6f, and performs a vacuum valve function by the mutual combination thereof. In addition, the second valve seat 6i is formed at the rear end of the plunger 6d to perform the air valve function in combination with the front end of the poppet valve 6f, thereby controlling the inflow of external air. That is, when the tip of the poppet valve 6f is seated on the first valve seat 6h, the positive pressure passage 6b is closed, and when the seat of the poppet valve 6f is seated on the second valve seat 6i, the transformer passage 6c is closed and the transformer chamber 3 is closed. ) Is blocking the inflow of air.

In addition, first and second springs 6j and 6k are provided in the air suction portion 6a of the valve body 6. The first spring 6j supports between the fixing member 6g and the input shaft 7 to return the input shaft 7 to the rear side when the brake is released, and the second spring 6k returns the poppet valve 6d to the first. And elastically support the second valve seats 6h and 6i.

On the other hand, in order to improve the feeling of pedaling by the initial brake driver (not shown), it is desirable to reduce the initial braking load acting on the input shaft 7, and to reduce the mounting load of the first spring 6j. Advantageously, the conventional brake booster, in which the poppet valve 6f is elongated in the form of a corrugated pipe so that a large area between the front end and the rear end of the poppet valve 6f is exposed to the atmospheric pressure of the air suction part 6a, has a first valve seat 6h. The tip end of the poppet valve 6f in a state seated on the side of the poppet valve is difficult to be separated from the first valve seat 6h, thereby reducing the mounting load of the first spring 6j.

SUMMARY OF THE INVENTION The present invention has been made to solve this problem, and an object of the present invention is to provide a brake boosting device provided to reduce an initial braking load without significantly affecting return performance.

In order to solve this problem, the brake booster includes: a casing having an interior divided into a constant pressure chamber and a transformer chamber; An air suction unit built in one side of the casing and communicating with the atmosphere, a positive pressure passage configured to communicate the positive pressure chamber and the transformer chamber in an open state, and the air suction unit and the transformer chamber in an open state; A valve body having a transformer passage provided to allow the valve body to be provided; A plunger installed in the front end of the valve body so as to move forward and backward; An input shaft provided to advance the plunger in the center of the air suction unit; A poppet valve provided in a ring shape provided to be retractable along the longitudinal direction of the input shaft in the air suction portion around the input shaft to control the air inflow; A first valve seat formed on an inner wall of the air suction part of the valve body to close the positive pressure passage in contact with the tip of the poppet valve; A second valve seat provided at a rear end of the plunger to close the transformer passage in contact with the front end of the poppet valve; A first spring having one end supported by the input shaft for the return of the input shaft; A second spring elastically supporting the poppet valve toward the first and second valve seats; A cover member provided to support the other end of the first spring and surround the poppet valve rear side; And a communication chamber provided between the poppet valve, the cover member, and the inner wall of the valve body to receive the second spring, the communication chamber communicating with the transformer flow passage through a connection channel passing through the inner wall of the valve body. .

The poppet valve includes an inner diameter inner sealing lip provided to be guided to the screening member, an outer diameter outer sealing lip provided to be guided to the inner wall of the valve body, and a body connecting the inner sealing lip and the outer sealing lip. Characterized in that.

The screen member includes a fixing part fixed to the inner wall of the valve body, the fixing part is provided with a mounting groove, the mounting groove is mounted with a sealing member for sealing between the valve body inner wall and the fixing part. It features.

As described above, the brake booster according to the present invention has a structure of a poppet valve provided in a ring shape and a cover member provided to cover and cover the rear side of the poppet valve. The area of the exposed poppet valve is reduced, so that the tip of the poppet valve is easily separated from the first valve seat, thereby improving the return performance of returning the input shaft. Therefore, even if the brake booster according to the present invention reduces the mounting load of the first spring to reduce the initial braking load acting on the input shaft does not significantly affect the return performance of returning the input shaft relative to the conventional.

1 is a cross-sectional view showing the overall structure of a conventional brake booster.
2 is a cross-sectional view showing the structure of a brake booster according to an embodiment of the present invention.
3 is an enlarged cross-sectional view of the valve body structure of FIG. 2 showing an initial state of the brake booster.

Next, a brake booster according to an exemplary embodiment of the present invention will be described in detail with reference to FIGS. 2 and 3.

2 and 3, the brake booster according to the present embodiment includes a casing 10 in which the front shell 11 and the rear shell 12 are hermetically coupled, and a positive pressure chamber in front of the casing 10. The pressure piston 41 and the diaphragm 42 partitioned into the transformer chamber 30 at the rear and the rear, and the pressure piston chamber is disposed so as to slide freely to move the central portion of the power piston 41 and the diaphragm 42. 20 and the valve main body 50 which controls the inflow of air to the transformer chamber 30, the input shaft 60 which operates the valve main body 50 by operation of a brake pedal (not shown), and doubles by differential pressure. The output shaft 70 is provided with a reaction disk 71 between the input shaft 60 so as to receive the applied force. Here, the pipe 11a installed on the front of the casing 10 is connected to an external negative pressure source (such as an intake manifold of the vehicle), whereby the positive pressure chamber 20 is maintained at low pressure. For reference, reference numeral 13 is a return spring for elastically supporting the valve body 50.

The valve body 50 has a multi-stage stepped cylindrical shape, one end of which is coupled to the center of the power piston 41 and the diaphragm 42. The other end of the valve body 50 passes through the center portion of the rear shell 12 to form an air suction part 61 in communication with the outside atmosphere. The input shaft 60 is located at the center of the air intake 61.

In addition, the valve main body 60 has a positive pressure passage 62 provided to communicate the constant pressure chamber 20 and the transformer chamber 30, and a transformer passage 63 provided to communicate the transformer chamber 30 with the atmosphere. One end of the cylinder 64 is provided in the axial direction. The cylinder 64 is provided with a plunger 65 in such a manner as to be retractable so as to slide in the axial direction in association with the end of the input shaft 60.

The positive pressure passage 62 communicates the positive pressure chamber 20 and the transformer chamber 30 in an open state, and the air pressure passage 63 opens the air suction part 61 and the transformer chamber 30 in an open state. To communicate with. In addition, the plunger 65 is moved forward by the input shaft 60 when braking, and the input shaft 60 which has been moved forward returns to the rear side through the elastic restoring force of the first spring 66 when the brake is released. The first spring 66 is formed in a truncated cone shape, and the rear end of the first spring 66 is supported around the outer surface of the input shaft 60 on which the step is formed, and the front end is supported by the screening member 100 to be described later.

In addition, the inside of the valve body 50 is provided with a poppet valve 80 that substantially controls the inflow of air by the operation of the input shaft 60 toward the inner wall of the air intake portion 61 which becomes the circumference of the input shaft 60. The poppet valve 80 is provided in a ring shape through an elastic material so that the poppet valve 80 can be moved forward and backward along the longitudinal direction of the input shaft 60, and inner inner sealing lip 81, outer outer sealing lip 82, and It is configured to include a body 83 for connecting the inner sealing lip 81 and the outer sealing lip 82.

A first valve seat 91 is provided on the inner wall of the valve body 50 so as to perform a vacuum valve function in combination with the tip of the poppet valve 80, so that the tip of the poppet valve 80 is seated on the first valve seat 91. When the positive pressure passage 62 is closed. A second valve seat 92 is provided at the rear end of the plunger 65 to perform an air valve function in combination with the front end of the poppet valve 80, and the front end of the poppet valve 80 is connected to the second valve seat 92. When seated, the transformer passage 63 is closed to block communication between the atmosphere and the transformer chamber 30. The poppet valve 80 is elastically supported toward the first and second valve seats 91 and 92 through the second spring 67 installed at the rear.

On the other hand, the brake booster according to the present embodiment is improved in the structure of the poppet valve 80 to reduce the initial braking load without significantly affecting the return performance.

First, the cover member 100 is provided on the inner diameter side and the rear side of the poppet valve 80 to cover and cover the rear side of the poppet valve 80, and the poppet valve 80, the cover member 100, and the cover member ( The connection between the inner wall of the valve body 50 receives the second spring 67 and penetrates the inner wall of the valve body 50 along the longitudinal direction of the input shaft 60 toward the outer diameter of one side of the poppet valve 80. A communication chamber 110 communicating with the transformer flow passage 63 through the flow passage 68 is provided.

The shielding member 100 includes a guide part 101 provided on the inner diameter side of the poppet valve 80 so as to be parallel to the inner wall of the valve body 50 so as to guide the inner sealing lip 81 when the poppet valve 80 operates. A spring support portion 102 extending vertically from the guide portion 101 to support the rear end of the two springs 67, and a fixing portion provided at the end of the spring support portion 102 to be fixed to the inner wall of the valve body 50 ( 103). A mounting groove 103a is provided in the fixing part 103 and a sealing member 120 is mounted in the mounting groove 103a for sealing between the screen member 100 and the inner wall of the valve body 50.

In addition, the outer sealing lip 82 of the poppet valve 80 is guided to the inner wall of the valve body 50 opposite to the guide portion 101 of the cover member 100 when the poppet valve 80 operates. The tip of the spring 66 is provided to be supported by the obstruction member 100 between the spring support portion 102 and the fixing portion 103.

Therefore, the brake booster according to the present embodiment is the first valve of the poppet valve 80 through the cover member 100 provided to cover and cover the rear side of the poppet valve 80 and the poppet valve 80 provided in a ring shape. The area of the poppet valve 80 exposed to the atmospheric pressure of the air intake portion 61 in the state seated on the seat 91 is reduced to facilitate the separation of the tip of the poppet valve 80 from the first valve seat 91. As a result, the return performance of returning the input shaft 60 is improved. Therefore, the brake booster provided in this way has a great influence on the return performance of returning the input shaft 60 relatively compared to the related art even though the mounting load of the first spring 66 is reduced so that the initial braking load acting on the input shaft 60 is reduced. Will not affect.

In addition, the communication chamber 110 in communication with the transformer passage 63 through the connection passage 68 forms the same negative pressure as the transformer chamber 30 in a state in communication with the transformer chamber 30, thereby poppet valve (80) Since the front and the rear is in the state of pressure equilibrium, at this time, only the spring force of the second spring 67 acts as a force pushing the poppet valve 80 toward the front side, so that the return action of the input shaft 60 is further made. It's easy.

The following describes the operation of the brake booster configured as described above.

In the initial state as shown in FIGS. 2 and 3, when the driver steps on the brake pedal (not shown) and the input shaft 60 moves forward, the plunger 65 is pushed toward the reaction disc 71 so that the second valve seat 92 and the poppet are pushed. The tip of the valve 80 is spaced apart so that the transformer passage 63 is opened. Accordingly, the atmosphere is introduced into the vacuum transformer chamber 30 through the transformer passage 63 and the diaphragm 42 and the power piston 41 are pushed to the output shaft 70 together with the valve body 50. The output is transmitted to the master cylinder assembly through the reaction disk 71 and the output shaft 70 to generate a braking pressure.

During this braking operation, the return spring 13 and the first spring 66 are compressed to elastically support the output shaft 70, the valve body 50, and the input shaft 60. The second spring 67 elastically supports the poppet valve 80 in the forward direction of the input shaft 60 so that the tip of the poppet valve 80 is in contact with the first valve seat 91.

When the driver releases the brake pedal (not shown), the plunger 65 and the input shaft 60 are restored by the elastic restoring force of the return spring 13 and the first spring 66 and at the same time the tip of the poppet valve 80. Is pushed backward by the second valve seat 92, in which the air is formed through the cover member 100 provided to cover and cover the rear side of the poppet valve 80 and the poppet valve 80 provided in a ring shape. The poppet valve 80 having a small area exposed to the atmospheric pressure of the suction part 61 is easily spaced apart from the first valve seat 91, whereby the positive pressure passage 62 and the transformer passage 63 communicate with each other to change the pressure. Air in the chamber 30 exits to the constant pressure chamber 20 in a vacuum state. Subsequently, this air is forced out through the pipe 11a associated with the negative pressure source, so that the brake booster is returned to its initial state.

50: valve body 60: input shaft
61: air suction portion 62: constant pressure passage
63: transformer passage 65: plunger
66: first spring 67: second spring
68: connection path 70: output shaft
80: poppet valve 81: inner sealing lip
82: outer sealing lip 83: body
91: first valve seat 92: second valve seat
100: cover member 101: guide portion
102: spring support 103: fixed portion
103a: mounting groove 110: communication room
120: sealing member

Claims (3)

A casing in which the inside is divided into a constant pressure chamber and a transformer chamber; An air suction unit built in one side of the casing and communicating with the atmosphere, a positive pressure passage configured to communicate the positive pressure chamber and the transformer chamber in an open state, and the air suction unit and the transformer chamber in an open state; A valve body having a transformer passage provided to allow the valve body to be provided; A plunger installed in the front end of the valve body so as to move forward and backward; An input shaft provided to advance the plunger in the center of the air suction unit; A poppet valve provided in a ring shape provided to be retractable along the longitudinal direction of the input shaft in the air suction portion around the input shaft to control the air inflow; A first valve seat formed on an inner wall of the air suction part of the valve body to close the positive pressure passage in contact with the tip of the poppet valve; A second valve seat provided at a rear end of the plunger to close the transformer passage in contact with the front end of the poppet valve; A first spring having one end supported by the input shaft for the return of the input shaft; A second spring elastically supporting the poppet valve toward the first and second valve seats; A cover member provided to support the other end of the first spring and surround the poppet valve rear side; And a communication chamber provided between the poppet valve, the screening member, and the inner wall of the valve body to receive the second spring, the communication chamber communicating with the transformer flow passage through a connection channel penetrating through the inner wall of the valve body. Brake booster. The method of claim 1,
The poppet valve includes an inner diameter inner sealing lip provided to be guided to the screening member, an outer diameter outer sealing lip provided to be guided to the inner wall of the valve body, and a body connecting the inner sealing lip and the outer sealing lip. Brake booster, characterized in that. The method of claim 1,
The screening member has a fixing part fixed to the inner wall of the valve body, the fixing portion is provided with a mounting groove, the mounting groove is mounted with a sealing member for sealing between the valve body inner wall and the fixing portion Featuring a brake booster.
KR1020100056829A 2010-06-16 2010-06-16 Brake booster KR20110136914A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
KR1020100056829A KR20110136914A (en) 2010-06-16 2010-06-16 Brake booster

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
KR1020100056829A KR20110136914A (en) 2010-06-16 2010-06-16 Brake booster

Publications (1)

Publication Number Publication Date
KR20110136914A true KR20110136914A (en) 2011-12-22

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Family Applications (1)

Application Number Title Priority Date Filing Date
KR1020100056829A KR20110136914A (en) 2010-06-16 2010-06-16 Brake booster

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20180065537A (en) 2016-12-08 2018-06-18 주식회사 만도 Brake booster for vehicle

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20180065537A (en) 2016-12-08 2018-06-18 주식회사 만도 Brake booster for vehicle
KR101868842B1 (en) * 2016-12-08 2018-06-21 주식회사 만도 Brake booster for vehicle

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