JPS6147739B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention comprises a casing divided into a low pressure chamber and a working chamber by a movable wall movable in a direction along a longitudinal centerline; a reinforcing tube extending in the direction and passing through the movable wall and fixed to the two end walls of the casing with both ends positioned in a direction along the longitudinal centerline; bent toward the low pressure chamber; a rolling diaphragm which moves with the movable wall and keeps the low pressure chamber and the working chamber airtight from each other; a slot formed in the reinforcing tube in the low pressure chamber and extending in a direction along the longitudinal centerline; a radial rib that is integrally provided on the wall, extends radially inward, is inserted into the slot of the reinforcing tube, and moves in the slot along the longitudinal centerline as the movable wall moves; ; has a control valve housing movable along the longitudinal centerline within the reinforcing tube and connected via a push rod to the drive piston of the master cylinder, which is operated from the outside to connect the working chamber and the low pressure; a control valve that isolates communication between the chamber and the working chamber and communicates the working chamber with the atmosphere; a sleeve that is coupled at one end to the control valve housing and to the radial rib at the other end; Regarding boosters.

If the brake booster is conventionally placed between the vehicle's dash panel and the master cylinder of the brake system, a significant portion of the reaction force generated in opposition to the force applied to the brake booster during braking is applied to the brake. It is transmitted from the master cylinder to the dash panel via the booster casing. A concrete proposal for making the construction of the casing lighter by reducing this reaction force applied to the casing is described in German Patent Application No. 2845794, in which the two ends of the casing are A tension-loaded component, shaped like a tie rod, is located between the walls, ie, between the master cylinder and the dash panel. This tie rod extends in a direction along the longitudinal centerline of the brake booster and penetrates the movable wall.
In order to maintain airtightness between the low-pressure chamber and the work chamber, it is necessary to seal the penetrating portion of the movable wall, and this sealing structure not only increases manufacturing and assembly costs, but also increases the cost of the above-mentioned sealing. The configuration for this is easily damaged.

In the brake booster described in DE 2837911.5, the interconnecting member interconnecting the two end walls of the casing is constituted by a reinforcing tube. Here, since the control valve housing is incorporated in the reinforcing tube, in order to transmit force from the movable wall to the control valve housing, a slot extending in the longitudinal direction is formed in the reinforcing tube, and a slot is formed in the reinforcing tube. A connecting member is inserted through the connecting member to connect the movable wall outside the reinforcing tube and the control valve housing inside the reinforcing tube.

The slot of the reinforcing tube is arranged in the region of the working chamber, and the inner edge of the movable wall is sealed along the longitudinal centerline on the outer circumferential surface of the reinforcing tube in the region of the low-pressure chamber where no slot is formed. Move in the direction of the ivy. Since the distance of movement of the movable wall on the outer circumference of the reinforcing tube in the area of the low-pressure chamber is equal to the length of the slot located in the area of the working chamber, the length of the reinforcing tube is equal to the distance of movement of the movable wall. The total length of the brake booster in the direction along the longitudinal centerline is also relatively large.

DE 2918913.7 discloses a brake booster whose overall length in the direction along the longitudinal centerline can be reduced. Here, the sealing member is constituted by a rolling diaphragm, and the rolling portion of the rolling diaphragm is arranged in the gap between the movable wall and the outer peripheral surface of the reinforcing tube on the working chamber side. When the brake is not activated, the rolling portion of the rolling diaphragm is folded on the outer peripheral surface of the reinforcing tube to a length that is half the moving distance of the movable wall. When the brake is applied, the folded rolling portion of the rolling diaphragm extends toward the low pressure chamber on the outer circumferential surface of the reinforcing tube, and when the brake is not applied, the folded rolling portion of the rolling diaphragm extends over the outer circumferential surface of the reinforcing tube located in the low pressure chamber. Duplicate slots.

With such an arrangement, it is desirable to make the slot as narrow as possible to prevent the rolling diaphragm from being damaged by the edges of the slot. In this case, the radial ribs inserted into the slots must also be constructed as thin as possible. However, on the other hand, the radial rib in the direction along the longitudinal centerline is The dimensions of the directional ribs must be relatively large. Increasing the dimensions of the radial ribs along the longitudinal centerline of the brake booster necessarily increases the overall length of the brake booster.

Furthermore, since the amount of force that must be transferred from the movable wall to the control valve housing through the radial ribs inserted through the slots in the reinforcing tube is considerable, the sleeves attached to the control valve housing from the radial ribs are The force transmitting member formed in the sleeve in order to transmit force to the brake booster also has to have a relatively large length along the longitudinal center line, which also increases the overall length of the brake booster. It contributes greatly to this.

The present invention has been made based on the above circumstances, and an object of the present invention is to not only prevent the sealing member necessary between the movable wall and the reinforcing tube from being damaged by the slot formed in the reinforcing tube. An object of the present invention is to provide a brake booster for an automobile that has a simple mechanism for transmitting force from a coupling member to a control valve housing, can reduce weight, and can have a small overall length.

The object of the invention is to provide a casing which is divided into a low pressure chamber and a working chamber by a movable wall movable in the direction along the longitudinal centerline; a reinforcing tube that penetrates the movable wall and is fixed to two end walls of the casing with both ends located in a direction along the longitudinal centerline; bent toward the low pressure chamber and moved with the movable wall; A rolling diaphragm that keeps the low pressure chamber and the working chamber airtight from each other; formed into a reinforcing tube in the low pressure chamber, extending in the direction along the longitudinal center line, and extending from one end near the rolling diaphragm before braking. A slot whose distance to the bending part of the rolling diaphragm is set to be at least half of the travel distance of the movable wall; inserted,
a radial rib that moves along the longitudinal centerline in the slot due to the movement of the movable wall; a radial rib that is movable along the longitudinal centerline within the reinforcing tube and that drives the master cylinder's drive piston via a push rod; a control valve housing connected to the control valve housing, the control valve being operated from the outside to cut off communication between the working chamber and the low pressure chamber and communicating the working chamber with the atmosphere; a sleeve whose other end is joined to the radial rib; and the sleeve is bent radially outward from the other end in a direction along the longitudinal centerline. a radial collar that engages the radial rib from the side of the low pressure chamber; a protrusion that engages the radial rib from the side and couples the other end of the sleeve with the radial rib; each of the radial ribs and the radial collar of the sleeve is the same in plurality; the number of radial collar portions are provided, and the length in the circumferential direction of each of the plurality of radial collar portions is set to be approximately equal to the length in the circumferential direction of each of the plurality of radial ribs of the same number, and the sleeve is The plurality of radial collar portions have a longitudinal collar portion extending from a circumferential end of each of the plurality of radial collar portions in a direction along the longitudinal center line toward one end of the sleeve; A slot is formed in one of the pair of longitudinal collar portions extending from the circumferential ends of each of the plurality of longitudinal collar portions for allowing relative movement of the radial rib in the circumferential direction with respect to the sleeve. a distance in the circumferential direction between the pair of longitudinal collar portions extending from each circumferential end of the radial collar portion is greater than a length in the circumferential direction of each of the plurality of radial ribs; This is achieved by an automobile brake booster characterized by:

In other words, with this configuration, the rolling diaphragm does not roll onto the slot extending in the longitudinal direction of the reinforcing tube during braking, so even if the longitudinal slot is made very wide, the rolling diaphragm will not be damaged. .

Furthermore, by forming the longitudinal slot of the reinforcing tube wide, the radial rib of the movable wall can also be configured relatively wide, so that the dimension of the radial rib in the direction along the longitudinal centerline can be made relatively wide. Even if they are small, the radial ribs can transmit a large amount of force applied to the movable wall and can shorten the overall length of the brake booster in the direction along the longitudinal centerline, also reducing the weight can do.

Further, in the automotive brake booster according to the present invention, the sleeve is bent radially outward from the other end and engaged with the radial rib from the low pressure chamber side in a direction along the longitudinal centerline. The radial collar portion engages the radial rib from the side of the working chamber to clamp the radial rib in cooperation with the radial collar portion in a direction along the longitudinal centerline, and the other end of the sleeve is radially The provision of the projections for coupling with the ribs greatly simplifies the construction of the fixing means for achieving fixation along the longitudinal center line of the radial ribs relative to the sleeve. Although this protrusion is capable of transmitting only a relatively small force, the radial collar of the sleeve of the control valve housing that receives the force from the radial rib has a dimension along the longitudinal centerline that is equal to the thickness of the sleeve. Instead of being made as small as possible, it can be made very wide, so that the sleeve connected to the control valve housing can be loaded from the movable wall through the radial ribs and the radial collar without any hindrance. The entire length of the brake booster along the longitudinal centerline can be further reduced, and the weight can be reduced.

Furthermore, in the automotive brake booster according to the present invention, the same number of the radial ribs and the radial collar portions of the sleeve are provided, and each of the radial collar portions of the plurality of radial collar portions is the same number. The length in the circumferential direction is set to be approximately equal to the length in the circumferential direction of each of the plurality of radial ribs having the same number, and the sleeve extends from the circumferential end of each of the plurality of radial collar portions to the longitudinal center line. a radius of the movable wall that overlaps the radial collar of the sleeve in a direction along the longitudinal centerline; Circumferential fixation can be achieved between a pair of longitudinal collars by bringing the directional rib into circumferential contact with the other non-slotted longitudinal collar. Therefore, it is possible to simplify the construction of the rotation locking mechanism for determining a predetermined relative position in the circumferential direction between the radial collar portion of the sleeve and the radial rib of the movable wall.

In the automotive brake booster of the present invention, one of the pair of longitudinal collar portions extending from the circumferential end of each of the plurality of radial collar portions has a radial rib relative to the sleeve in the circumferential direction. A slot is formed to allow movement in the plurality of radial directions, and a distance in the circumferential direction between the pair of longitudinal collar portions extending from each peripheral end of the plurality of radial collar portions is equal to Since it is larger than the length of each rib in the circumferential direction,
The radial collar portion of the sleeve and the radial ribs of the movable wall can be connected by bayonet connection, making the connection operation extremely easy. In addition, the connection between the radial collar and the radial rib is such that the protrusion of the sleeve cooperates with the radial collar of the sleeve to clamp the radial rib of the movable wall, so that no rotational movement occurs thereafter. No loosening occurs.

Further, in the automobile brake booster of the present invention configured as described above, a plurality of radial collar portions of the sleeve are provided with a direction extending along the longitudinal collar portion from the other end of the sleeve toward one end. forming a pair of extending openings;
Another one is connected to the longitudinal collar portion at each longitudinally extending end of the pair of openings and extends outward in the radial direction.
Preferably, two radial collars are formed.

With such a configuration, the plurality of openings can provide a space for assembling the screws necessary to secure the master cylinder and the reinforcing tube to the end wall of the housing. At the same time, however, the structure of the sleeve, weakened by the formation of the plurality of openings, can be reinforced by the additional radial collar.

Further, in the automobile brake booster of the present invention, the movable wall has a diaphragm plate, and the radial rib can be formed integrally with the diaphragm plate. Such an arrangement not only significantly reduces the weight of the brake booster, but also ensures a stable transmission of force via the radial ribs from the movable wall to the sleeve of the control valve housing.

Furthermore, in the automotive brake booster of the present invention, instead of the above-described structure, the movable wall may include a diaphragm plate and a spacer ring coupled to the diaphragm plate, and the spacer ring may be provided with radial ribs. . With this configuration, the diaphragm plate can be made thin regardless of the total amount of force applied to the radial ribs.

Furthermore, in the automotive brake booster of the present invention, the movable wall extends from the diaphragm plate into the low pressure chamber in a direction along the longitudinal centerline at a position radially outward from the diaphragm plate and the reinforcing tube. The radial rib is integrally formed on the extending end of the hub member, and the rolling diaphragm, which is bent toward the low pressure chamber on the inner peripheral surface of the hub member, is brought into close contact with the rolling diaphragm before the braking operation. A generally cylindrical insert may be provided that contacts the.

With such a configuration, the rolling diaphragm can also transmit the differential pressure in the housing to the movable wall at the contact portion with the substantially cylindrical insert, thereby improving the operating efficiency of the brake booster.

The above and other features and objects of the present invention will become more apparent from the following description with reference to the accompanying drawings.

The brake booster for a motor vehicle shown in FIG. 1 has a casing 1 which is divided into a working chamber 3 and a low-pressure chamber 4 by a movable wall 2 which is movable along the longitudinal centerline. A reinforcing tube 5 is arranged concentrically in the casing 1, and the reinforcing tube 5 extends in the direction along the longitudinal center line, and both ends of the reinforcing tube 5 are connected to the two parts of the casing 1 by bolts 8 and 9.
It is fixed to the end walls 6, 7.

The movable wall 2 has a diaphragm plate 10 and a diaphragm 11 supported by the diaphragm plate 10, and the diaphragm 11 is arranged between the outer peripheral edge of the diaphragm plate 10 and the inner surface of the peripheral wall of the casing 1. An outer rolling diaphragm 12 and a diaphragm plate 1 that make the gap between the outer periphery and the inner surface airtight
The inner rolling diaphragm 13 is disposed between the inner circumferential edge of the reinforcing tube 5 and the outer circumferential surface of the reinforcing tube 5 and makes the gap between the inner circumferential edge and the outer circumferential surface airtight. 4
It is bent towards the front. The working chamber 3 and the low pressure chamber 4 in the casing 1 are made airtight from each other by the diaphragm 11.

Control valve 1 driven by piston rod 14
Reinforcement tube 5 on the side where 5 is close to the work chamber 3
The control valve 15 is located at the end of the control valve piston 16 connected to the piston rod 14.
have. Before the braking operation shown in FIG. 1 is started, that is, before the piston rod 14 is pressed, the control valve 15 opens the valve hole in the control valve housing 17 to move the working chamber 3 into the low pressure chamber. It communicates with 4. When a braking operation is started, that is, when the piston rod 14 is moved to the left in the figure along the longitudinal center line by being pressed by a brake pedal (not shown), the control valve 15 closes the valve hole. As a result, communication between the low pressure chamber 4 and the working chamber 3 is cut off and the working chamber 3 is communicated with the atmosphere, so that the movable wall 2 pressed by atmospheric pressure moves toward the low pressure chamber 4.

The control valve housing 17 is movable within the reinforcing tube 5 along its longitudinal center line and includes a push rod 18 which acts on the drive piston of the master cylinder (not shown) of the brake unit. are connected. The master cylinder is fixed to the end of the reinforcing tube 5 on the side closer to the low pressure chamber 4 by bolts 9. A compression spring 19 supported between one end wall 7 of the casing 1 on the side of the low pressure chamber 4 and the diaphragm plate 10 moves the movable wall 2 into the working chamber 3 in the illustrated position before the start of the brake operation. It is biased toward the other end wall 6 of the side casing 1.

In the illustrated embodiment, the control valve housing 17 is made of plastic and has a radially outwardly extending flange 20 at its end adjacent to the working chamber 3. A sleeve 21 extending from the control valve housing 17 toward the low pressure chamber side of the movable wall 2 is integrally engaged with the flange 20, and the extending end of the sleeve 21 is bent radially outward. It has two first radial collars 22. These first radial collars 22
is a radially inwardly extending end of the hub member 24, which is a tap-shaped, substantially cylindrical, formed on the inner circumferential edge of the diaphragm plate 10 and extends into the low pressure chamber 4. From the side of the working chamber 3 it engages a radial rib 23 which is configured as a flat tongue and inserted into two longitudinal slots 29 of the reinforcing tube 5. Here, the radial rib 23, the hub member 24 and the diaphragm plate 1
0 is integrally formed from a thin sheet metal.

A longitudinal collar portion 25 (FIG. 2) extends from the circumferential end of each of the two first radial collar portions 22 of the sleeve 21 in the direction of the working chamber 3 along the longitudinal center line. A second radial collar portion 26 extends radially outward from the extending end of the directional collar portion 25 . Also sleeve 21
Between the pair of first radial collar portions 22,
A pair of openings are formed along the longitudinal collar 25 from the extending end of the sleeve 21 to the second radial collar 26 . One of the pair of longitudinal collar parts 25 connected to the peripheral ends of each of the pair of first radial collar parts 22 has a section extending from the first radial collar part 22 along the longitudinal center line. A lateral insertion slot 27 is provided at a position with a slight gap in the longitudinal direction. Sleeve 21-2
Since the circumferential distance between the two first radial collar portions 22 is set slightly larger than the circumferential distance between the two radial ribs 23 of the diaphragm plate 10, the sleeve 21 When connecting the diaphragm plate 10 and the diaphragm plate 10, first the two radial ribs 23 of the diaphragm plate 10 are connected between the two first radial collars 22.
The sleeve 21 is moved in the direction along the longitudinal center line relative to the diaphragm plate 10 with the side insertion slot 27 and the two radial ribs 23 arranged in the same plane. , the sleeve 21 is then rotated 90 degrees circumferentially relative to the diaphragm plate 10 to push the radial ribs 23 of the diaphragm plate 10 into the lateral insertion slots 27 so that the two first radial It overlaps with the collar part 22. In this position, the radial rib 23 of the diaphragm plate 10 connects the sleeve 21 with the protrusion 28 projecting radially outward from the outer peripheral surface of the sleeve 21.
diaphragm plate 10 does not move relative to sleeve 21 in the direction along the longitudinal centerline.

In the state shown in Fig. 1 before the start of brake operation,
The distance a between the inner rolling diaphragm 13 and one end of the longitudinal slot 29 on the side adjacent to the working chamber 3 is set to at least half the travel distance of the movable wall 2. Therefore, even when the movable wall 21 is closest to the end wall 7 of the casing 1 on the low pressure chamber 4 side during brake operation,
The inner rolling diaphragm 13 does not overlap entirely over the longitudinal slot 29.

In the area of the inner rolling diaphragm 13, the end of the hub member 24 of the diaphragm plate 10 which is close to the working chamber 3 has a cylindrical shape and a radial extension between the hub member 24 and the diaphragm plate 10. A radially outwardly curved plastic insert 30 is inserted along the border and supports the inner rolling diaphragm 13.

When assembling the automobile brake booster according to the embodiment as described above, first the radial rib 23 of the diaphragm plate 10 is inserted into the longitudinal slot 2 of the reinforcing tube 5 from the low pressure chamber side.
It is inserted into 9. The control valve 15, on which the sleeve 21 has already been fitted by preassembly, is then inserted into the reinforcing tube 5. and then the diaphragm plate 10 until the radial rib 23 of the diaphragm plate 10 overlaps the first radial collar 22 of the sleeve 21 as described above.
The sleeve 21 is rotated 90 degrees in the circumferential direction relative to 0. Next, by forming the protrusion 28 on the sleeve 21, the connection between the sleeve 21 and the diaphragm plate 10 is reliably maintained.

In FIG. 3, the outer shapes of the hub member 24 and the radial ribs 23 are shown by dashed lines.

In the modification shown in FIG. 4, the extending end portion 32 of the hub member 24 of the diaphragm plate 10 is
spacer ring 3 formed independently from 4;
1, and a radial rib 23 is formed on the inner peripheral surface of this spacer ring 31. The diaphragm plate 10 and the hub member 24 are integrally formed of thin sheet metal. The extending end portion 32 of the hub member 24 supports the outer peripheral surface 33 of the spacer ring 31, and is formed on the end surface of the extending end portion 32.
The spacer ring 31 is fixed to the hub member 24 by engaging a tongue-shaped portion 34 bent inward in the radial direction with a recess formed in the outer peripheral surface of the spacer ring 31.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional view showing a brake booster for an automobile based on an embodiment of the present invention; FIG.
A side view showing only the sleeve connected to the control valve housing in the automobile brake booster shown in the figure; FIG. 3 is a sectional view taken along the - line in FIG. 2; FIG. 4 is a radial direction of the diaphragm plate. It is a longitudinal cross-sectional view which shows the modification of a rib. DESCRIPTION OF SYMBOLS 1... Casing, 2... Movable wall, 3... Working chamber, 4... Low pressure chamber, 5... Reinforcement tube, 10...
...Diaphragm plate, 11...Diaphragm, 12...Outer rolling diaphragm, 13...
... Inner rolling diaphragm, 14 ... Piston rod, 15 ... Control valve, 16 ... Control valve piston, 17 ... Control valve housing, 18 ... Push rod, 19 ... Compression spring, 20 ... Flange, 21
... sleeve, 22 ... first radial collar section, 23 ... radial rib, 24 ... hub member,
25... Longitudinal store collar portion, 26... Second radial collar portion, 27... Lateral insertion slot, 28
...Protrusion, 29...Longitudinal slot, 30...
Insert, 31...Spacer ring, 32...Extending end, 33...Outer peripheral surface, 34...Tongue-shaped part.

Claims (1)

[Scope of Claims] 1. A casing divided into a low pressure chamber and a working chamber by a movable wall movable in a direction along the longitudinal centerline; a reinforcing tube that penetrates the movable wall and has both ends fixed to two end walls of the casing located in a direction along the longitudinal center line; is bent toward the low pressure chamber and moves with the movable wall; and a rolling diaphragm that keeps the low pressure chamber and the working chamber airtight from each other; a reinforcing tube is formed in the low pressure chamber, extends in a direction along the longitudinal center line, and extends from one end near the rolling diaphragm before braking. a slot whose distance to the bending part of the rolling diaphragm is set to at least half of the travel distance of the movable wall; and a slot of a reinforcing tube that is integrally provided in the movable wall and extends radially inward; a radial rib that is inserted through the reinforcing tube and moves in a direction along the longitudinal centerline through the slot due to movement of the movable wall; a control valve having a control valve housing connected to a driving piston of the cylinder, the control valve being operated from the outside to cut off communication between the working chamber and the low pressure chamber and communicating the working chamber with the atmosphere; a sleeve having one end coupled to the housing and the other end coupled to the radial rib; the sleeve being bent radially outwardly from the other end along the longitudinal centerline; a radial collar that engages the radial rib from the low pressure chamber side in the longitudinal direction; and a radial collar that cooperates with the radial collar to clamp the radial rib in the longitudinal direction a projection that engages the radial rib from the working chamber side and couples the other end of the sleeve with the radial rib; each of the radial rib and the radial collar of the sleeve; are provided in the same number, and the circumferential length of each of the plurality of radial collar portions is set to be approximately equal to the circumferential length of each of the plurality of the same number of radial ribs,
the sleeve has a longitudinal collar extending from a circumferential end of each of the plurality of radial collars in a direction along a longitudinal centerline toward one end of the sleeve; A slot is formed in one of the pair of longitudinal collar portions extending from each circumferential end of the directional collar portion to allow relative movement of the radial rib in the circumferential direction with respect to the sleeve; A distance in the circumferential direction between a pair of longitudinal collar portions extending from a circumferential end of each of the plurality of radial collar portions is greater than a length in the circumferential direction of each of the plurality of radial ribs. An automobile brake booster characterized by: 2. The brake booster for an automobile according to claim 1, wherein the movable wall has a diaphragm plate, and the radial rib is integrally formed with the diaphragm plate. 3. The movable wall comprises a diaphragm plate and a spacer ring connected to the diaphragm plate, and the radial rib is formed on the spacer ring. The mentioned automotive brake booster. 4. The movable wall includes a diaphragm plate and a hub member extending from the diamond frame plate into the low pressure chamber in a direction along the longitudinal centerline at a position radially outward from the reinforcing tube. , the radial rib is integrally formed on the extending end of the hub member, and the inner circumferential surface of the hub member is in close contact with a rolling diaphragm bent toward the low pressure chamber before the braking operation. 2. A brake booster for a motor vehicle according to claim 1, further comprising a contacting generally cylindrical insert. 5. An opening extending from the other end of the sleeve toward the one end along the longitudinal collar is formed between the plurality of radial collars of the sleeve, and the opening extends from the other end of the sleeve toward the one end. Claim 1, characterized in that each longitudinally extending end is formed with another radial collar portion that is connected to the longitudinal collar portion and extends radially outward. The mentioned automotive brake booster. 6. The automobile brake booster according to claim 5, wherein the movable wall has a diaphragm plate, and the radial rib is integrally formed with the diaphragm plate. 7. Claim 5, characterized in that the movable wall has a diaphragm plate and a spacer ring connected to the diaphragm plate, and the radial rib is formed on the spacer ring. The mentioned automotive brake booster. 8. The movable wall has a diaphragm plate and a hub member extending from the diaphragm plate into the low pressure chamber in a direction along the longitudinal centerline at a position radially outward from the reinforcing tube, The radial rib is integrally formed on the extending end of the hub member, and the inner peripheral surface of the hub member is in close contact with a rolling diaphragm that is bent toward the low pressure chamber prior to braking operation. 6. A brake booster for an automobile according to claim 5, further comprising a substantially cylindrical insert having a substantially cylindrical shape.