JPH05330420A - Adjusting method for jumping characteristic gap in negative pressure boost device - Google Patents

Abstract

PURPOSE:To adjust a brake feeling arbitrarily, easily and stably by easily changing jumping in a simple constitution. CONSTITUTION:In the half built-up state of a negative pressure boost device, a measuring means 17 for detecting the axial displacement is provided on a negative pressure constant pressure chamber ra1. When the interior of the negative pressure constant pressure chamber ra1 is put in the negative pressure state and an input rod 11 is displaced above a specified amount, detection is conducted by the measuring means 17 to perceive the inhibit position of a valve plunger 9, and the distance from the perceived position to the positions of the valve plunger 9 and a reaction disc is taken as a gap (d) for jumping characteristic.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a negative pressure type booster used for a vehicle brake device and the like, and relates to a jumping characteristic.

[0002]

2. Description of the Related Art As a prior art relating to the present invention, there is, for example, the one disclosed in Japanese Utility Model Laid-Open No. 2-102869.

In this prior art, a control valve mechanism which is operated by a push rod and controls the pressure difference between the front and rear chambers of the power piston is incorporated in the power piston, and the power piston moves in the forward direction generated in the power piston by the pressure difference. A large-diameter hole into which the rear end of the output member that takes out thrust is slidably inserted, and a valve plunger in the control valve mechanism that is connected to the front end of the push rod by communicating with the large-diameter hole through the step The front end of the power piston has a small diameter hole slidably fitted between the large diameter hole and the small diameter hole of the power piston. Having a fixed first gap, the rod member is retracted after assembly by using a jig to regulate the rotation of the annular member, and the rod member is arbitrarily moved between the second contact surface and the reaction disc. 2 gaps In Rukoto are those easily adjust the brake feeling jumping amount change arbitrarily and easily.

[0004]

However, the characteristic (jumping characteristic) showing the relation of the output load to the input load of the negative pressure type booster obtained by this type of reaction force mechanism is that the reaction disc outputs at the time of boosting operation. It is compressed by the member and the power piston and elastically deforms in the small diameter hole, and pushes the valve plunger toward the push rod to apply a reaction force to the brake pedal. Therefore, the jumping amount is the same as the second gap at the rear end. , The first end of the valve plunger
It is difficult to adjust the jumping amount because it is determined by the mutual relationship with the gap, the hardness of the rubber, and the like. Also, when using a jig from the outside to adjust the jumping amount,
The jumping amount cannot be adjusted unless the master cylinder is deeply fitted between the front shell and the output member. In other words, the structure that holds the output member and the front shell in an airtight manner does not have a passage for the jig to pass through the output member and cannot change the jumping amount because it holds it in an airtight manner. There was a problem. Therefore, there is a problem that the jumping adjustment of the negative pressure type booster is not suitable for mass production and is not feasible.

Therefore, the present invention solves the above-mentioned problems in a negative pressure type booster, that is, by changing the jumping amount easily with a simple structure and stabilizing the brake feeling arbitrarily and easily. The technical task is to be able to adjust by adjusting.

[0006]

[Constitution of the invention]

[0007]

SUMMARY OF THE INVENTION The technical problem of the present invention taken to solve the above-mentioned technical problem is that the inside of the housing connecting the front shell and the rear shell is the hub member and the outer peripheral part thereof is the housing. Is divided into a negative pressure constant pressure chamber and a variable pressure chamber by a power piston which is airtightly fixed to the hub member and has an inner periphery which is airtightly fixed to the hub member, and is incorporated into the power piston. The output that the differential pressure between the variable pressure chamber and the negative pressure constant pressure chamber is controlled by the operation of the valve mechanism linked to the input rod, and the operating force applied to the valve plunger connected to the input rod is assisted and transmitted by the power piston. In a negative pressure type booster equipped with a rod and a reaction disc that transmits force to the output rod, a hub member and a duct are provided inside the housing. A negative pressure constant pressure chamber is provided with a measuring means for measuring axial displacement in a semi-assembled state in which a yaf ram, a power piston, an input rod, a valve mechanism and a valve plunger are incorporated, and the negative pressure constant pressure chamber is in a negative pressure state. West,
In the negative pressure state, the input rod is displaced in the axial direction by a predetermined amount or more, the stop position of the valve plunger is detected from the measuring means, and the position of the valve plunger and the reaction disc is used for the jumping characteristic from the detected position. It is characterized by having a gap.

As a second means, a hollow member forming a negative pressure constant pressure chamber in a semi-assembled state in which a hub member, a diaphragm, a power piston, an input rod, a valve mechanism and a valve plunger are incorporated in a housing. A hollow cylindrical member, a sliding member that can slide in the hollow cylindrical member in the axial direction, a seal member that hermetically holds the outer circumference of the hollow cylindrical member and the inner circumference of the sliding member, and A rod that penetrates the shaft and is inserted into the through hole, and a displacement meter that detects the displacement of the disk contact surface of the hub member and the valve plunger by fixing one side of the rod to the valve plunger and fixing the other side to the sliding member. It is connected to.

A third means is characterized in that the jumping characteristic gap can be adjusted to any desired position by using some reaction disks.

A fourth means is characterized in that the jumping characteristic gap can be adjusted to an arbitrary position by a number of valve plungers.

[0011]

According to the above-mentioned technical means of the present invention, the negative pressure constant pressure chamber is in a semi-assembled state in which the hub member, the diaphragm, the power piston, the input rod, the valve mechanism and the valve plunger are incorporated in the housing. A measuring means for measuring the axial displacement is installed in the negative pressure constant pressure chamber, and the measuring means detects when the input rod is displaced by a specified amount or more in the negative pressure state, and the valve plunger is stopped from the valve plunger stop position. By detecting the gap between the reaction disc and the reaction disc and selecting that reaction disc from several reaction discs so that it will be at an arbitrary position, that is, the gap, the jumping amount can be changed easily and arbitrarily Can be easily and stably adjusted.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments embodying the technical means of the present invention will be described in detail below with reference to the accompanying drawings.

First, in FIG. 1, a normal cross-sectional view is shown when the present invention is applied to a single type negative pressure type booster for a brake, and a housing 1 of this negative pressure type booster 30 has a cup shape. And a plate-shaped rear shell 3 that is airtightly attached to the rear end of the front shell 2 and is attached to a vehicle dashboard (not shown) at the rear. The power piston 4 and the diaphragm 5 partition the pressure chamber ra1 as a front chamber Ra and the variable pressure chamber rb1 as a rear chamber Rb.

The power piston 4 is formed by integrally connecting a hub member 6 made of a resin material and a metal power plate 7. The outer peripheral portion of the diaphragm 5 is hermetically held by the joint portion of the front shell 2 and the rear shell 3. The inner peripheral portion of the diaphragm 5 is hermetically held by the inner peripheral edge of the power piston 4 and the hub member 6.

The constant pressure chamber ra1 is connected to an intake manifold (not shown) of the engine from a port 8 provided in the housing 1 via a check valve (not shown), and is always under negative pressure during operation of the engine.

The valve mechanism 20 is operated by a well-known operation and selectively communicates the variable pressure chamber rb1 with the constant pressure chamber ra1 or the atmosphere, and is constituted by a valve plunger 9, a control valve 10 and the like.

The valve plunger 9 is connected to the tip end of an input rod 11 which interlocks with a brake pedal (not shown) at its rear end (on the right side in the figure), and the output rod 13 is axially moved through a reaction disc 12 described later. It is movable. One end of the output rod 13 extends through the front shell 2 in an airtight manner to the housing 1, and is connected to a master cylinder (not shown). Further, the rear (right side in the figure) tip forms a storage portion 13a for storing the reaction disc 12,
Are arranged. In the non-actuated position shown, between the valve plunger 9 and the reaction disc 12,
A predetermined gap d is formed.

Further, in FIG. 2, which is the present invention shown in FIG. 2 for improving the brake feeling relating to the jumping characteristic by keeping the gap d constant, the negative pressure booster 30 is completed, that is, the reaction disk. Before mounting the 12, the output rod 13 and the front shell 2 on the rear shell, a hollow cylindrical member 14 used as a substitute for the front shell 2 is provided and fixed to the rear shell 3 in an airtight manner. The hollow cylindrical member 14 is provided with a port 18 so as to pressurize the atmosphere and communicates with the vacuum 19.

The hollow cylindrical member 14 is provided with a sliding member 15 which is slidable in the axial direction. A seal member 21 that hermetically holds the inner circumference of the hollow cylindrical member 14 and the outer circumference of the sliding member 15 is fixed to the hollow cylindrical member 14.
In the shaft center of the sliding member 15, the valve plunger 9 is penetrated, and the rod 16 is inserted into the passage.
Above the rod 16 in the figure, a displacement gauge 17 such as a dial gauge that detects axial displacement is attached to the sliding member 15 by fixing the rod 16 with a nut or the like. Further, the lower part of the rod 16 in the drawing always indicates the valve plunger 9
Is in contact with.

The value detected by the displacement meter 17 is the gap d. As shown in the figure, the displacement gauge 17 is in a state where A is filled with negative pressure. In B, the stroke of the input rod 11 causes the sliding member 15 to slide upward, and the valve mechanism 2
The process in which 0 is balanced with the differential pressure generated by the sliding member 15 is shown. This differential pressure is set to be approximately the same as the return spring load (not shown) when the negative pressure type booster 30 is assembled. In C, the valve plunger 9 pushes up the rod 16,
The valve mechanism 20 balances the differential pressure and the input load applied to the input rod 11 to balance the valve plunger 9 and the rod 1.
6 and the sliding member 15 are stopped to make a stable state.
At this time, if the stroke of the input rod 11 is equal to or greater than the specified amount (equal to or greater than the control valve stroke), a stable numerical value is exhibited. (Also, here, the gap d of the required jumping amount is set to 1 mm, and the vacuum 19
Is set to 500 mmHg. ) Therefore, the gap d for the jumping characteristic of the negative pressure type booster 30 in the partially assembled state
In the adjusting method, for example, the non-operating position in which a negative pressure of 500 mmHg is press-fitted into the constant pressure chamber ra1 from the vacuum 19 through the port 18 and the constant pressure chamber ra1 is filled with the negative pressure is shown by the displacement gauge 17. As shown by A, the rod 16 pushes the input rod 11 and the like downward via the valve plunger 9 and the control valve 10. At this time, there is no pressure difference between the constant pressure chamber ra1 and the variable pressure chamber rb1, and the pressures in both chambers are equal.

Further, when the input rod 11 is stroked, the tension of the displacement gauge 17 shows C shown in the figure, and the valve plunger 9 pushes the rod 16 upward. When the input rod 11 is further stroked to reach a prescribed amount or more, the atmosphere is gradually supplied to the variable pressure chamber rb1 so that the valve mechanism 20 balances with the differential pressure of the sliding member 15, and both chambers ra1 and ra2.
A pressure difference between 1 and rb1 occurs. Along with that, the tension of the displacement gauge 17 gradually approaches in the direction B shown in the drawing, the pressure difference between the two chambers ra1 and rb1 balances with the differential pressure of the sliding member 15, and the sliding member 15, the valve plunger 9 and the rod 16 are balanced. Will stop. Along with that, the position of the tension is B
When stabilized at the position of, the gap d related to the jumping characteristic is
To detect. (That is, an input load is applied to the negative pressure type booster 30 to detect d in an unloaded state in which a reaction force does not work.) In the drawing shown in FIG. 3, when the value detected by the displacement gauge and the gap d do not match, In other words, the value of the displacement gauge is over,
Alternatively, it is an embodiment in which the reaction disk 12 can be adjusted when the value is negative.
The reaction disk 12 is made of rubber and has elasticity. In addition, here, the convex portion 12a and the concave portion 12
Five reaction disks a1, a flat portion 12b, a concave portion 12c, and a concave portion 12c1 are provided.

As a method of selecting the reaction disk 12, for example, the convex portion 12a is formed with a thickness of 0.2 mm. The portion of the convex portion 12a1 is formed with 0.1 mm. The recess 12c is formed to have a thickness of 0.1 mm. The portion of the recess 12c1 is formed with a thickness of 0.2 mm.

Therefore, when the gap d detected by the displacement gauge 17 does not reach the predetermined value, for example, the gap d is set to 1 mm here, and therefore the numerical value of the gap d exceeds the predetermined value of 1 mm by +0.2 mm. If so, the housing portion 13a of the output rod 13 is fitted by using (1) of FIG. The value of the gap d is 0.1 mm from the predetermined value of 1 mm
If it is protruding, (2) in FIG. 3 is used. If the numerical value of the gap d is equal to the predetermined value, (3) in FIG. 3 is used.
If the value of the gap d is 0.1 less than the predetermined value of 1 mm,
(4) of FIG. 3 is used. The value of the gap d is 1m, which is the specified value
If it is 0.2 mm less than m, (5) in FIG. 3 is used.

Further, the variation amount of the gap d is determined by the hub member 6,
It occurs depending on the length of the valve plunger 9 and the amount of the rubber parts of the valve mechanism 20 that bite into it. However, if this amount is investigated in advance, the optimum range of unevenness and the type of disk can be determined. Along with that, a stable gap d can be obtained.

Further, although the single type booster is used, the tandem type negative pressure booster can also be used.

Further, in another embodiment as a method of adjusting the gap d, only a part of the structure of the negative pressure booster is different, and the structure excluding the part is a known technique. ,
Since it can be understood by those skilled in the art, the description of the configuration except a part is omitted.

A hub member 100, which is hollow in part, is provided.
A valve plunger 101 that is movable in the axial direction is provided inside, but a first valve plunger 101a that connects the valve plunger 101 to the tip of a control valve 102 that interlocks with a brake pedal (not shown), and a reaction disc 103. The second valve plunger 101a1 which is interlocked with the output rod 104 via the second rod plunger 101a1 is divided into two parts. The gap d is divided into two parts by adjusting the length of the second valve plunger 101a1. First valve plunger 101a and second valve plunger 1
01a1 is an engagement relationship. Second valve plunger 1
A gap d relating to the jumping characteristic is formed between 01a1 and the reaction disk 102.

Therefore, the negative pressure type booster 30 in a partially assembled state
In the method of adjusting the gap for the jumping characteristic, referring to FIG. 4, δ−gap d1 = 13, and the reaction disk 103 and the second valve plunger 10 are obtained from the equation.
If the gap 1a1 is measured and the gap d that has been determined is not satisfied or if it is overfilled and excessively exceeded, the optimum second valve plunger 101a1 is selected and assembled so that the gap d is determined. To

Further, referring to FIG. 5, in the method of dividing into two, in FIG. 4, the first valve plunger 101a and the second valve plunger 101a1 are not connected,
Since the lengths of the guide portions 100a and 100b that divide into two in a limited space become short, resistance may occur between the inner circumference of the hub member 100 and the outer circumference of the valve plunger 101. Therefore, in order to reduce the sliding resistance by defining the hub member 100 and the guide portions 100a and 101b of the valve plunger 101, the first valve plunger 101
The second valve plunger 101a1 and the second valve plunger 101a1 are connected by an elastic member 105 which is elastic and formed into a substantially C-ring tubular shape. This makes it possible to slide without causing resistance.

The method described above can also be used for both a single-type negative pressure booster and a tandem-type negative pressure booster. Further, according to the method using the displacement gauge 17, the valve mechanism 20 due to the difference in the shape of the hub valve seat of the valve mechanism 20 and the difference in the load of the spring of the valve mechanism 20.
Since the variation in the bite amount, the variation in the valve plunger length, and the variation in the length of the hub member are absorbed, the jumping amount can be adjusted stably.

[0031]

As described above, according to the present invention, in the housing, the hub member, the diaphragm, the power piston, the input rod, the valve mechanism and the valve plunger are assembled in a semi-assembled state. The pressure constant pressure chamber is provided with a measuring means for measuring with displacement in the axial direction, and the negative pressure constant pressure chamber is in a negative pressure state and the input rod is displaced by a predetermined amount or more, and the measuring means performs detection to detect the valve plunger. The clearance between the valve plunger and the reaction disk is detected from the stop position, and the reaction disk is selected from several reaction disks so that the desired position, that is, the clearance, can be selected to easily and arbitrarily change the jumping amount. As a result, the brake feeling can be adjusted easily and stably, and the intended purpose can be achieved.

[Brief description of drawings]

FIG. 1 is a cross-sectional view before applying the present invention.

FIG. 2 is a sectional view showing an embodiment of the present invention.

FIG. 3 is a structural diagram of a reaction disc showing an embodiment of the present invention.

FIG. 4 is a partial cross-sectional view showing another embodiment of the present invention.

FIG. 5 is a partial cross-sectional view showing another embodiment of the present invention.

[Explanation of symbols]

1 Housing 2 Front Shell 3 Rear Shell 4 Power Piston 5 Diaphragm 6 Hub Member, 100 Hub Member 7 Power Plate 8 Port 9 Valve Plunger 10 Control Valve 11, 102 Input Rod 12, 12a, 12a1, 12b, 12c, 12c1
Reaction disk 13,104 Output rod, 13a Storage part 14 Hollow cylindrical member 15 Sliding member 16 Rod 17 Displacement meter 18 Port 19 Vacuum 20 Valve mechanism 30 Negative pressure booster 101 Valve plunger, 101a First valve plunger 101a1 Second valve Plunger, 101b Guide part 105 Elastic member Ra Front chamber Rb Rear chamber ra1 Constant pressure chamber rb1 Transformer chamber

Claims (4)

[Claims] 1. A hub member and an outer peripheral portion thereof are airtightly fixed to the housing, and an inner periphery thereof is airtightly fixed to the hub member in a housing connecting a front shell and a rear shell. A power piston composed of one diaphragm divides the negative pressure constant pressure chamber and the variable pressure chamber into a negative pressure constant pressure chamber and a variable pressure chamber, and a valve mechanism incorporated in the power piston and interlocked with an input rod operates between the variable pressure chamber and the negative pressure constant pressure chamber. An output rod having a differential pressure controlled so that an operating force applied to a valve plunger connected to the input rod is transmitted by being assisted by the power piston, and a negative electrode provided with a reaction disc for transmitting the force to the output rod. In the pressure type booster, the hub member, the diaphragm, and the power piston are provided in the housing. In the semi-assembled state in which the input rod, the valve mechanism and the valve plunger are assembled, a measuring means for measuring the displacement in the axial direction is provided in the negative pressure constant pressure chamber, and the negative pressure constant pressure chamber is placed in the negative pressure state, In the negative pressure state, the input rod is displaced in the axial direction by a predetermined amount or more, and the stop position of the valve plunger is detected from the measuring means, and the position between the valve plunger and the reaction disk is jumping characteristic from the detected position. A method for adjusting a gap for a jumping characteristic in a negative pressure type booster, which is characterized in that the gap is used for a purpose. 2. The negative pressure constant pressure chamber in a semi-assembled state in which the hub member, the diaphragm, the power piston, the input rod, the valve mechanism and the valve plunger are incorporated in the housing. A hollow hollow cylindrical member to be formed, a sliding member that can slide in the hollow of the hollow cylindrical member in the axial direction, and an outer periphery of the hollow cylindrical member and an inner periphery of the sliding member are hermetically held. A seal member, a rod penetrating the axis of the sliding member and inserted into the penetrating member, and one side of the rod abutting against the valve plunger and the other side fixed to the sliding member of the hub member. 2. The negative pressure type booster according to claim 1, which is connected to a displacement gauge for measuring the axial displacement of the disk contact surface and the valve plunger. 3. The adjustment of the jumping characteristic gap in a negative pressure type booster according to claim 1, wherein the jumping characteristic gap can be adjusted by some reaction discs so that it is located at an arbitrary position. Method. 4. The method for adjusting the jumping characteristic gap in the negative pressure type booster according to claim 3, wherein the jumping characteristic gap can be adjusted by using several valve plungers so that the jumping characteristic gap is located at an arbitrary position.