SU1428630A1 - Double-duty master brake cylinder - Google Patents

Abstract

The invention relates to the field of transport engineering and concerns the design of the main brake cylinders of hydraulic systems for controlling the brakes of an automobile and valve devices of the metering type. The purpose of the invention is to increase the speed. In the housing 1 there is a piston separating the working 4 and the rod cavity in the housing, and a valve assembly 17 for communicating the working cavity 4 with the rod one, having a spring-loaded locking element. A washer 18 is coaxially mounted in the lid 10 with a throttle bore 19 communicating with the cavity 4 of the cylinder, and a stepped piston 20, the rod part of which is spring-loaded relative to the clamps 10, and the shut-off element of the relief valve is equipped with a pusher placed in the rod cavity 25 above the piston 20. As the check valve of the bypass valve is used a swing-type check valve 23, the shank of which protrudes into the cavity 25. 2 Cp f-ly, 3 ill. (L

Description

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W 2S

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W 2S 21 22

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FIG. 2

one

The invention relates to the field of mechanical engineering and concerns the construction of main brake cylinders of hydraulic brake control systems for automobiles and metering valve devices.

The purpose of the invention is to increase the speed.

Figure 1 shows a dual-brake master brake cylinder, general view; figure 2 - node I in figure 1; on fig.Z same option.

The dual-mode brake master cylinder comprises a housing 1 in which a piston 2 is installed with a stem 3, a working 4 in the housing and a rod 5 of a cavity. A cuff 6 is installed in front of the piston 2, a spring 7. is pressed to it, and is located between the piston 2 and the washer 8, mounted on the stem of the rod 3. and the spring 9 pressed to it. In the cover 10 there is an opening 11 communicating with the wheel cylinders (brake cylinders The rod cavity is sealed to the housing with a ring 12 and communicates with the brake fluid reservoir 13 through a pumping valve 14 mounted in the housing 15 and spring-loaded spring 16. The working cavity 4 and the rod cavity 5 are interconnected through a plug element of the valve assembly 17 mounted 10 in valve assembly (FIG. 2) consists of washers 18c coaxially installed in KpbmjKe 10 with a throttle bore 19 communicating with the working cavity 4, and a stepped piston 20 whose rod part is spring-loaded with a spring 21 relative to the top cover 22. The locking element of the valve assembly 17 is made in the form of a swing-type check valve 23, spring-loaded spring 24 and installed in the valve block housing 17 so that the shank of the swing-valve 23 projects in the rod cavity 25 of the valve assembly 17 above the step 26 of the piston 2 0. The stepped piston 20 is sealed in the housing with a sealing ring 27, and in the sleeve 28 with a ring 29, and has an abutment 30 for limiting the maximum movement of the piston 20 in order to prevent the swinging shank of the swing valve 13. The rod 25 has a hollow through pipe 31 associated with the rod end 5 of the master brake cylinder. Locking element

one

ten

15

20

25

,

ZO 55

4286302

valve block 17 (FIG. 3) is made in the form of a spring-loaded spring 32 of a ball check valve 33, equipped with a ball pusher 34 installed in valve block 17 protruding in the rod cavity 25 above the piston step 35, having a tapered surface 36. The stepped piston 35 is equipped with an abutment to limit the movement of the pusher 34 from the check valve 33, made in the form of a cylindrical surface 37.

The main brake cylinder operates as follows.

When moving the rod 3 rests on the piston 2 and moves it to the right, the liquid is displaced from the working cavity 4 into the wheel brake cylinders. In this case, the cuff 6 provides sealing of the working cavity 4, separating it from the rod cavity 5. In the latter, when the rod is moved to the right, the brake fluid flows from the reservoir 13 through the check valve 14 due to the discharge that exists here. When pressure in the cavity 4 is determined by the spring 21 and the piston 20 area, the piston 20 moves while compressing the spring 21, while in the throttle bore 19 the fluid entering the working cavity of the piston 20 is throttled. As the pressure increases in the cavity 4, the piston 2Q all the way into the shank of the swinging valve 23, the shut-off valve 23 opens and communicates the working cavity 4 with the cavity 25 and then with the rod cavity 5. The pressure in the rod cavity 5 increases until the pressure on the bottom of the piston 20 is balanced, the pressure in the rod end 25, the actual 1m-step-sided end face of the pistons 20, and the force of the spring 21. Thus, the following action of the valve assembly 17 is performed. Due to the fact that in the cavity 5 there appears an excess pressure of the working fluid the gear ratio of the master brake cylinder changes and the pressure in the working brake cylinders r increases. In the case of the valve assembly 17 in accordance with the embodiment of FIG. 3, when the piston 20 moves, the conical surface 36 displaces the pusher 34 to the non-return valve 33, the non-return valve 33 opens and informs the working cavity

35

40

45

50

4 with the rod end 5. The valve block is designed to operate as described.

The proposed brake master cylinder works reliably with both smooth and abrupt (shock) depressing the brake pedal, since the throttle bore 19 causes the fluid entering the working cavity of the piston 20 to be throttled, which ensures the required delay time of the valve unit 17 required to increase the pressure in the wheel brake cylinders to a certain level.

Claims (3)

1. A dual-mode brake master cylinder comprising a housing in which a piston separating the working and rod cavities is installed, and a valve assembly for communicating the working cavity with the rod, having a spring-loaded locking element of the relief valve, a spring-loaded piston coaxially fitted with a washer with the throttle, communicating the working cavity with a step, limiting the movement between the washer and the spring of the pusher into the rod of the cavity-filled piston, is different from the beginning of the body part. / S / s In order to improve speed, the spring-loaded piston is made stepped with a rod and installed in a separate body part rigidly connected to the body, in which a bypass channel communicating the rod cavity in the body part with the working cavity is made, the bypass channel and is made with a pusher protruding into the rod end of the body part for interacting with a spring-loaded piston, while the rod spaces of the body part and the body are interconnected oh through an external bypass pipeline. 2. The cylinder of claim 1, wherein the relief valve is of the swing-type check valve. 3. The POP.1 cylinder, which is also distinguished by the fact that the spring-loaded stepped piston is made with a conical surface for interaction with the pusher, made between the larger piston stage and its smaller iO FIG. f Compiled S.Makarov Editor L.Gratillo Tehred A.Kravchuk Proofreader. M.Sharoshi Order 5084/21 Circulation 569 VNIIPI USSR State Committee for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5 Fig.Z Subscription