Hydraulic parking braking system and road roller

Abstract

The utility model discloses a hydraulic parking brake system and a road roller. The hydraulic parking brake system comprises a hydraulic pump, an overflow valve, an electromagnetic directional valve, a brake oil cylinder and a hydraulic oil tank, an oil inlet of the hydraulic pump is connected with the hydraulic oil tank, an oil outlet of the hydraulic pump is connected with a first oil way and a second oil way which are connected in parallel, the first oil way is connected with the electromagnetic directional valve, the electromagnetic directional valve is connected with the brake oil cylinder and the hydraulic oil tank, the second oil way is connected with an overflow valve, and the overflow valve is connected with the hydraulic oil tank. According to the hydraulic parking braking system, the independent braking oil cylinder is adopted for braking, when the engine is started, the braking oil cylinder relieves braking, and when the engine flames out, parking braking of the whole machine is achieved.

Description

Technical Field

[0001] The utility model relates to a hydraulic parking brake system and a road roller, belonging to the technical field of road roller braking. Background Art

[0002] As an engineering machine with high compaction quality and high compaction efficiency, road rollers are widely used in road construction. At present, the parking brake system of hydraulically driven light road rollers in China is mostly a motor-built brake, which is in a normal braking state. It is necessary to introduce a low-pressure hydraulic oil into the brake chamber to push the spring open and release the brake of the friction plate. The driving system of this type of light road roller is often a closed hydraulic system.

[0003] An existing light roller commonly uses an open hydraulic system, which is composed of a gear pump, a cycloidal motor and a multi-way valve. However, the drive motor does not have a brake and a parking function, and cannot meet the use requirements. Summary of the invention

[0004] In view of the problems existing in the prior art, the utility model provides a hydraulic parking brake system and a road roller.

[0005] In order to achieve the above-mentioned purpose, the utility model adopts a hydraulic parking brake system, including a hydraulic pump, a relief valve, an electromagnetic reversing valve, a brake oil cylinder and a hydraulic oil tank;

[0006] The oil inlet of the hydraulic pump is connected to the hydraulic oil tank, and the oil outlet of the hydraulic pump is connected to a first oil circuit and a second oil circuit in parallel. The first oil circuit is connected to an electromagnetic reversing valve, and the electromagnetic reversing valve is respectively connected to the brake cylinder and the hydraulic oil tank. The second oil circuit is connected to an overflow valve, and the overflow valve is connected to the hydraulic oil tank.

[0007] In some embodiments, the hydraulic pump is a gear pump of an open system.

[0008] In some embodiments, the solenoid reversing valve is a two-position three-way solenoid reversing valve.

[0009] In some embodiments, the brake cylinder is a one-way cylinder.

[0010] In some embodiments, the relief valve is a low-pressure relief valve.

[0011] A second aspect of the utility model provides a road roller, on which the hydraulic parking brake system is installed.

[0012] Compared with the prior art, the hydraulic parking brake system of the utility model adopts an independent brake oil cylinder for braking. When the engine is started, the brake oil cylinder releases the brake, and when the engine is turned off, the whole machine realizes parking brake. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without paying any creative work.

[0014] Figure 1 It is the hydraulic principle diagram of the utility model;

[0015] In the figure: 1. hydraulic pump, 2. overflow valve, 3. solenoid reversing valve, 4. brake cylinder, 5. hydraulic oil tank. DETAILED DESCRIPTION

[0016] In order to make the objectives, technical solutions and advantages of the present invention more clear, the technical solutions of the present application are described in detail below through the accompanying drawings and specific embodiments. It should be understood that the embodiments of the present application and the specific features in the embodiments are detailed descriptions of the technical solutions of the present application, rather than limitations on the technical solutions of the present application. In the absence of conflict, the embodiments of the present application and the technical features in the embodiments can be combined with each other.

[0017] like Figure 1 As shown, a hydraulic parking brake system includes a hydraulic pump 1, a relief valve 2, an electromagnetic reversing valve 3, a brake cylinder 4 and a hydraulic oil tank 5;

[0018] The oil inlet of the hydraulic pump 1 is connected to the hydraulic oil tank 5, and the oil outlet of the hydraulic pump 1 is connected to a first oil circuit and a second oil circuit in parallel. The first oil circuit is connected to an electromagnetic reversing valve 3, and the electromagnetic reversing valve 3 is respectively connected to the brake cylinder 4 and the hydraulic oil tank 5. The second oil circuit is connected to an overflow valve 2, and the overflow valve 2 is connected to the hydraulic oil tank 5.

[0019] In some embodiments, the hydraulic pump 1 is a gear pump, which draws oil from the hydraulic oil tank 5 and outputs high-pressure oil; the high-pressure oil then reaches the electromagnetic reversing valve 3, and at the same time, a relief valve 2 is connected in parallel to the outlet of the gear pump, and the outlet of this relief valve 2 is connected back to the hydraulic oil tank 5 to ensure that the pressure of the entire system does not exceed the set pressure of the relief valve 2.

[0020] In some embodiments, the electromagnetic reversing valve 3 adopts a two-position three-way electromagnetic reversing valve. The control end of the electromagnetic reversing valve 3 is controlled by the power on and off of the electromagnetic valve. When the electromagnetic valve is energized, the reversing valve works in the left position, the pressure oil communicates with the brake cylinder 4, and the whole machine releases the brake; when the electromagnetic valve is de-energized, the hydraulic oil in the brake cylinder 4 communicates with the hydraulic oil tank 5, and the whole machine realizes parking brake.

[0021] In some embodiments, the brake cylinder 4 adopts a one-way cylinder. When the pressure oil enters the cylinder body, the spring of the brake cylinder 4 is pushed open and the brake is released; when the hydraulic oil in the cylinder body returns to the hydraulic oil tank 5, the cylinder piston extends out under the thrust of the spring and the whole machine is braked. The elastic force of this spring is not large, so this cylinder is only used for parking brake.

[0022] In some embodiments, the overflow valve 2 is a low-pressure overflow valve. When the pressure is higher than a certain value, the pressure oil entering the brake system directly returns to the hydraulic oil tank 5 to protect the entire parking brake system.

[0023] A second aspect of the utility model provides a road roller, on which the hydraulic parking brake system is installed.

[0024] When using:

[0025] The hydraulic pump 1 sucks oil from the hydraulic oil tank 5 and outputs high-pressure oil; the high-pressure oil reaches the electromagnetic reversing valve 3. When the electromagnetic valve is energized, the reversing valve works in the left position. At this time, the high-pressure oil reaches the cylinder body of the brake cylinder 4 through the electromagnetic reversing valve 3. At this time, the pressure oil acts on the bottom surface of the piston rod of the cylinder body, pushing the piston rod to the left, pushing open the spring of the rodless chamber of the cylinder, and releasing the brake;

[0026] When the solenoid valve is powered off, the reversing valve works in the right position. At this time, the high-pressure oil is disconnected from the reversing valve. At this time, the rod chamber of the brake cylinder 4 is connected to the hydraulic oil tank 5. The hydraulic oil in the rod chamber returns to the hydraulic oil tank 5 under the thrust of the spring in the rodless chamber. At this time, the high-pressure oil is depressurized, and the piston of the brake cylinder 4 is pushed out under the thrust of the spring force, and the brake cylinder 4 realizes braking.

[0027] At the same time, in order to ensure the smooth and safe running of the whole machine, this electromagnetic reversing valve 3 is energized when the engine of the whole machine is started, and the parking brake is released at this time; when the whole machine is turned off, this electromagnetic valve is de-energized, and the parking brake of the whole machine is implemented at this time.

[0028] The hydraulic parking brake system of the utility model adopts an independent brake oil cylinder for braking. When the engine is started, the brake oil cylinder releases the brake, and when the engine is turned off, the whole machine realizes parking brake.

[0029] In addition, those skilled in the art will understand that, although some embodiments described herein include certain features included in other embodiments but not other features, the combination of features of different embodiments also means being within the scope of protection of the present utility model and forming different embodiments. For example, in the above embodiments, those skilled in the art can use them in combination according to the known technical solutions and the technical problems to be solved by the present application.

Claims

1. A hydraulic parking brake system, characterized in that: It comprises a hydraulic pump (1), a relief valve (2), an electromagnetic reversing valve (3), a brake oil cylinder (4) and a hydraulic oil tank (5); The oil inlet of the hydraulic pump (1) is connected to the hydraulic oil tank (5), and the oil outlet of the hydraulic pump (1) is connected to a first oil circuit and a second oil circuit connected in parallel. The first oil circuit is connected to an electromagnetic reversing valve (3), and the electromagnetic reversing valve (3) is respectively connected to a brake cylinder (4) and a hydraulic oil tank (5). The second oil circuit is connected to an overflow valve (2), and the overflow valve (2) is connected to the hydraulic oil tank (5).

2. A hydraulic parking brake system according to claim 1, characterized in that: The hydraulic pump (1) is a gear pump of an open system.

3. A hydraulic parking brake system according to claim 1, characterized in that: The electromagnetic reversing valve (3) is a two-position three-way electromagnetic reversing valve.

4. A hydraulic parking brake system according to claim 1, characterized in that: The brake oil cylinder (4) is a one-way oil cylinder.

5. The hydraulic parking brake system according to claim 1, characterized in that: The relief valve is a low-pressure relief valve.

6. A road roller, characterized in that: The road roller is installed with the hydraulic parking brake system according to any one of claims 1 to 5.

Images