JPH0443413Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a brake hydraulic master cylinder, and more particularly to the structure of a switch case of a stop lamp switch attached to a cylinder body.

[Conventional technology]

For example, in a brake hydraulic master cylinder disclosed in Japanese Utility Model Application Publication No. 63-69095, a piston for generating hydraulic pressure is inserted into a cylinder hole formed in the cylinder body, and the piston is connected to a push lever connected to a brake pedal. A braking action is performed by pushing the piston, and the retraction limit of the piston is regulated by a stopper plate provided near the opening of the cylinder hole.

Further, the stop lamp switch is supported on a bracket bolted to the cylinder body, and when the actuator of the stop lamp switch fixed to the pushing member is separated from the stop lamp switch during braking operation, the stop lamp switch is activated. .

[The problem that the idea attempts to solve]

However, in the above structure, the stopper plate that regulates the retraction limit of the piston, the actuator of the stop lamp switch, and the bracket to which the stop lamp switch is screwed are each assembled to the cylinder body separately, so the number of parts is large. It takes time and effort to assemble and manage it. Furthermore, since the stop lamp switch and actuator are exposed, there is a concern that foreign matter may enter the switch.

Therefore, the present invention reduces the number of parts by integrally assembling these parts attached to the cylinder body, making the assembly and management easier, reducing assembly costs, and further, An object of the present invention is to provide a brake hydraulic master cylinder which prevents foreign matter from entering into a stop lamp switch and stabilizes the performance of the stop lamp switch over a long period of time.

[Means to solve the problem]

In order to achieve the above object, the present invention includes a piston for generating hydraulic pressure that is pushed by a pushing member inserted into a cylinder hole formed in a cylinder body, and a boss portion surrounding a relief port and a supply port is inserted into the cylinder hole. In a hydraulic master cylinder for brakes, a brake hydraulic master cylinder is provided with a switch case attached to a cylinder body, which houses a stop lamp switch that is formed in the body and is operated as the piston is pushed, and the switch case is fitted into the boss portion. A fitting part;
between a stopper protrusion that penetrates the cylinder body and protrudes into the cylinder hole to restrict the retraction limit of the piston, or a convex part that fits into a recess formed in the outer wall of the cylinder body, and the fitting part;
A stop lamp switch storage part is formed integrally with the stop lamp switch storage part, which is arranged to have an operating chamber that allows the movement of an actuator for operating the stop lamp switch, and the cylinder body is engaged with the piston or the pushing member. The actuator moves along
It is characterized in that the actuator is pressed and assembled to the stop lamp switch by a spring compressed between the fitting portion and the actuator in the actuation chamber.

Further, in the brake hydraulic master cylinder configured as described above, a connector communicating with a reservoir for supplying hydraulic fluid into the cylinder hole is integrally formed in the fitting portion of the switch case. It is said that

Furthermore, in the brake hydraulic master cylinder configured as described above, a fitting groove for the dust boot is formed on the outer wall of the stop lamp switch housing portion of the switch case, and the fitting groove is formed in the dust boot. and a fitting part that fits into the side wall of the cylinder body, a cover part that covers the stop lamp switch storage part and the actuator, and a fitting part that fits into the piston or the pushing member. It is said that

[Effect]

Therefore, the present invention has a fitting part fitted into a boss part surrounding the relief port and the supply port, and a stopper protrusion or projection that penetrates the cylinder body and projects into the cylinder hole to restrict the retraction limit of the piston. A stop lamp switch that is arranged with an operating chamber that allows movement of an actuator that operates the stop lamp switch between a convex part that fits into a recess formed in the outer wall of the cylinder body and the fitting part. An actuator that is integrally formed with the housing part and that engages with the piston or its pushing member and moves along the cylinder body is compressed between the fitting part and the actuator in the actuating chamber. By pressing and assembling the stop lamp switch with a spring, the switch case is assembled into a unit, and a connector that communicates with a reservoir that supplies hydraulic fluid into the cylinder hole is integrally formed in the fitting part of the switch case. Therefore, the number of parts attached to the cylinder body can be reduced, and since the dust boot covers the stop lamp switch and the actuator that operates it, it is possible to prevent foreign matter from entering the stop lamp switch.

〔Example〕

Hereinafter, embodiments of the present invention will be described based on the drawings.

FIG. 1 shows a first embodiment of the present invention, in which a brake hydraulic master cylinder 1 has a cylinder body 2 disposed in the vertical direction with a cylinder hole 3 that opens downward. A piston 4 for generating hydraulic pressure is fitted therein in a liquid-tight and movable manner, and a hydraulic chamber 5 is formed between the upper bottom of the cylinder hole 3 and the piston 4.
is defined.

The cylinder body 2 has a boss portion 7 on one side to which a hose 6 from a reservoir (not shown) is connected.
Vehicle body mounting brackets 8, 8 are provided protruding from the other side. A connector 9 for connecting the hose 6 and a switch case 11 of a stop lamp switch 10 are fitted into the boss portion 7, respectively, and are connected to each other through a relief port 12 and a supply port 13 surrounded by the boss portion 7. The cylinder hole 3 is supplied with hydraulic fluid from the reservoir.

The piston 4 is urged in a non-braking direction by a return spring 14 contracted in a hydraulic chamber 5 above the head 4a, and a pushing member connected to a brake pedal 15 is provided at the lower end of the shaft portion 4b. A certain push rod 16 is in contact.

The switch case 11 includes a ring-shaped fitting portion 11a that is fitted into the boss portion 7, and an iron plate 17 that penetrates the cylinder body 2 and projects into the cylinder hole 3 to restrict the retraction limit of the piston 4. The stopper protrusion 11b molded with the fitting part 1
1a, the stop lamp switch 10
An operating chamber 1 that allows movement of an actuator 18 that operates the
1d and a stop lamp switch housing 11c disposed in the working chamber 11d.
The stop lamp switch 10 is pressed and assembled into a unit by a spring 20 compressed between the fitting part 11a and the actuator 18.

Furthermore, a fitting groove 11e for a dust boot 19 is formed in the outer wall of the stop lamp switch storage section 11c of the switch case 11.

The actuator 18 has a switch operating piece 18b bent toward the outer circumference of the cylinder hole 3 at one end of a connecting portion 18a disposed along the stop lamp switch housing 11c, and a switch actuating piece 18b bent toward the inside of the cylinder hole 3 at the other end. A piston engaging piece 18c is formed, and the switch actuating piece 18b is pressed against the stop lamp switch 10 by a spring 20 disposed within the actuating chamber 11d.

The aforementioned unitized switch case 11
The ring-shaped fitting part 11a is fitted into the boss part 7, and the stopper protrusion 11b penetrates the side wall of the cylinder body 2 and projects into the cylinder hole 3 to restrict the retraction limit of the piston 4. The piston engaging piece 18c of the actuator 18 is arranged on the side of the cylinder body 2 of the plump switch 10, and the piston engaging piece 18c of the actuator 18
The cylinder body 2 is assembled into the cylinder body 2 by engaging with the switch plate 21 fitted onto the shaft portion 4b. In this case, the connector 9 may be integrally formed with the ring-shaped fitting portion 11a.

As a result, the actuator 18 moves the brake pedal 1
When the piston 4 is pushed upward through the push rod 16 by the rotation of the cylinder body 2, it moves upward in the working chamber 11d along the side wall of the cylinder body 2, and the switch operating piece 18b operates the stop lamp switch. The stop lamp switch 10 is operated at a distance from the stop lamp switch 10. Note that the actuator 18 may be pushed by the push rod 16.

Therefore, when the unitized switch case 11 is assembled to the cylinder body 2, the stopper protrusion 11b penetrates the side wall of the cylinder body 2 and protrudes into the cylinder hole 3, so that the switch case 11 is attached to the cylinder body 2. The piston 4 is prevented from rotating, and the retraction limit of the piston 4 can be restricted by the stopper protrusion 11b. By reducing the number of these parts, assembly and management can be facilitated, and assembly costs can be reduced.

Further, the stop lamp switch 10 and the actuator 18 are covered by a dust boot 19 disposed between the cylinder body 2 and the shaft portion 4b of the piston 4.

This dust boot 19 has a fitting part 19b that fits into a fitting groove 11e of the switch case 11 and a fitting groove 2a of the cylinder body 2 on the upper part of a cover part 19a that covers the stop lamp switch 10 and the actuator 18. , a fitting part 19c that fits into the shaft part 4b of the piston 4 is formed in the lower part, and water, sand,
Prevents foreign matter such as dust from entering and prevents the actuator 18 from entering.
It is possible to prevent the stop lamp switch 10 from malfunctioning due to flying stones or the like while driving, and to operate the stop lamp switch 10 stably for a long period of time.

FIG. 2 shows a second embodiment of the present invention, in which a piston 4 is fitted into a cylinder hole 3 of a cylinder body 2.
The retracting limit is restricted by a stopper ring 30 provided near the opening of the cylinder hole 3, and is urged in the non-braking direction by a return spring 31 compressed between the stopper ring 30 and the switch plate 21.

Further, the switch case 32 disposed on the side of the cylinder body 2 has a fitting part 32a fitted to the boss part 7, and a convex part 32b fitted to the recess 2a formed on the outer wall of the cylinder body 2. A stop lamp switch storage part 32c is integrally formed between the fitting part 32a and the stop lamp switch storage part 32c, which has an operating chamber 32d that allows movement of the actuator 18 that operates the stop lamp switch 10. At the same time, the piston 4 is engaged with the cylinder body 2.
The actuator 18, which moves along the actuator 18, is pressed and assembled to the stop lamp switch 10 by a spring 20 compressed between the fitting portion 32a and the actuator 18 in the actuation chamber 32d. ing. Further, a connector 9 is integrally formed in the fitting portion 32a, and the stop lamp switch storage portion 3
A fitting groove 32 for the dust boot 19 is provided on the outer wall of 2c.
e is formed.

This unitized switch case 32 is
The ring-shaped fitting part 11a with which the connector 9 is integrally formed is fitted into the boss part 7, and the convex part 32b is fitted into the recess 2a formed in the outer wall of the cylinder body 2, so that the switch case 32 is inserted into the cylinder. The stop lamp switch 10 is placed on the side of the cylinder body 2, and the piston engaging piece 18c of the actuator 18 is engaged with the switch plate 21 fitted to the piston 4. , is assembled to the cylinder body 2. Note that the actuator 18 may be pushed by the push rod 16.

Therefore, when the unitized switch case 32 is assembled to the cylinder body 2, the convex portion 32
The switch case 32 is prevented from rotating with respect to the cylinder body 2 by fitting into the recess 2a, and the connector 9 is integrally formed in the fitting part 32a.By reducing the number of these parts, Its assembly and management can be facilitated, and assembly costs can be reduced.

Note that the ring-shaped fitting portion 32a and the connector 9
It may be formed separately.

[Effect of idea]

As described above, in the present invention, a piston for generating hydraulic pressure that is pushed by a pushing member is fitted into a cylinder hole formed in a cylinder body, and is fitted into a boss portion surrounding a relief port and a supply port. a stopper protrusion that penetrates the cylinder body and protrudes into the cylinder hole to restrict the retraction limit of the piston, or a convex part that fits into a recess formed on the outer wall of the cylinder body; A stop lamp switch storage part is integrally formed between the parts and has an operating chamber that allows movement of the actuator for operating the stop lamp switch, and also engages with the piston or its pushing member to form a cylinder body. The switch case is made into a unit by pressing and assembling the actuating element that moves along the stop lamp switch with a spring compressed between the fitting part and the actuating element in the operating chamber. Therefore, when the switch case is assembled to the cylinder body, the stopper protrusion penetrates the side wall of the cylinder body and protrudes into the cylinder hole, or the convex part fits into the recess formed on the outer wall of the cylinder body. is fixed to the cylinder body so that it is securely attached to the cylinder body, and by reducing the number of these parts, assembly and management can be facilitated and assembly costs can be reduced.

Furthermore, by integrally forming a connector communicating with a reservoir that supplies hydraulic fluid into the cylinder hole in the fitting portion of the switch case, the number of parts attached to the cylinder body can be further reduced.

Furthermore, by covering the stop lamp switch and the actuator that operates it with a dust boot, it is possible to prevent foreign matter from entering the stop lamp switch, and prevent the actuator from malfunctioning due to flying stones while driving. In addition to preventing this, the stop lamp switch can be operated stably for a long period of time.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional front view of a master cylinder showing a first embodiment of the present invention, and FIG. 2 is a cross-sectional front view of a master cylinder showing a second embodiment. 1... Brake hydraulic master cylinder, 2...
Cylinder body, 2a... recess, 3... cylinder hole, 4... piston, 7... boss, 9... connector, 10... stop lamp switch, 11,
32... Switch case, 11a, 32a... Fitting part, 11b... Stopper protrusion, 11c, 32c
...Storage lamp switch storage section, 11d,
32d... Working chamber, 11e, 32e... Dust boot fitting groove, 12... Relief port, 13...
...Supply port, 16... Pushrod, 1
8... Actuator, 19... Dust boot, 32b...
...Protrusion.

Claims (1)

[Claims for Utility Model Registration] 1. A piston for generating hydraulic pressure that is pushed by a pushing member is fitted into a cylinder hole formed in a cylinder body, and a boss portion surrounding a relief port and a supply port is inserted into the cylinder hole. In a hydraulic master cylinder for brakes, the switch case is attached to the cylinder body and houses a stop lamp switch that is formed in the cylinder body and operates as the piston is pushed. a stopper protrusion that penetrates the cylinder body and protrudes into the cylinder hole to restrict the retraction limit of the piston, or a convex part that fits into a recess formed in the outer wall of the cylinder body; A stop lamp switch storage part is integrally formed between the part and the stop lamp switch storage part, which is disposed with an operating chamber that allows movement of an actuator for operating the stop lamp switch, and The actuator, which is engaged and moves along the cylinder body, is pressed and assembled to the stop lamp switch by a spring compressed between the fitting part and the actuator in the actuating chamber. A brake hydraulic master cylinder characterized by: 2. The brake hydraulic master cylinder according to claim 1, wherein the fitting portion of the switch case is integrally formed with a connector that communicates with a reservoir that supplies hydraulic fluid into the cylinder hole. 3. A fitting groove for a dust boot is formed on the outer wall of the stop lamp switch storage section of the switch case, and the dust boot has a fitting part that fits into the fitting groove and a side wall of the cylinder body, and a fitting part for fitting the dust boot. 3. The hydraulic master cylinder for brakes according to claim 1, further comprising a cover portion that covers the plump switch storage portion and the actuator, and a fitting portion that fits into the piston or the pushing member.