Parking brake system and agricultural machine

Abstract

The utility model relates to the field of hydraulic braking, and discloses a parking braking system and agricultural machinery, the parking braking system comprises a parking brake, a first reversing valve, a second reversing valve and an energy accumulator, a working oil port of the first reversing valve is connected with a rod cavity of a brake cylinder of the parking brake, an oil inlet of the first reversing valve is connected with an oil inlet path, and an oil outlet of the second reversing valve is connected with an oil outlet path; an oil return port of the first reversing valve is connected with an oil return path, in a power-off state, a working oil port of the first reversing valve is communicated with the oil return port, an oil outlet of the second reversing valve is connected with the oil return path, in the power-off state, an oil inlet of the second reversing valve is communicated with the oil outlet, and the energy accumulator is connected with the oil inlet of the second reversing valve. According to the parking braking system, the situation that tires are locked when the agricultural machine loses power accidentally in the running process can be avoided, and meanwhile the agricultural machine can be slowly and stably decelerated till the agricultural machine is stopped and parked.

Description

Technical Field

[0001] The utility model belongs to the field of hydraulic braking, and in particular relates to a parking brake system and agricultural machinery applying the parking brake system. Background Art

[0002] The parking brake system of existing agricultural machinery (such as silage loader) usually includes a parking brake and a reversing valve. The reversing valve controls the operation of the parking brake's brake cylinder to switch the parking brake between a braking state and a brake-released state. The specific working method is as follows: when the reversing valve is powered and switched to the first valve position, the spring in the rodless chamber of the brake cylinder is compressed, causing the piston rod to retract, and the parking brake is switched to the brake-released state. When the reversing valve loses power and switches to the second valve position, the spring in the rodless chamber of the brake cylinder resets, causing the piston rod to extend, and the parking brake is switched to the braking state. This working method poses a significant safety hazard. When the agricultural machinery accidentally loses power while driving, the reversing valve will immediately switch to the second valve position, causing the parking brake to immediately switch to the braking state, causing the tires to lock. At this time, safety accidents such as rollover are very likely to occur. Utility Model Content

[0003] In view of the above-mentioned deficiencies or defects in the prior art, the present invention provides a parking brake system and agricultural machinery, aiming to solve the technical problems of the existing parking brake systems of agricultural machinery having large safety hazards and low safety factors.

[0004] To achieve the above objectives, the present invention provides a parking brake system, which includes:

[0005] parking brake;

[0006] Oil return line, including damping components;

[0007] a first reversing valve, wherein the working oil port of the first reversing valve is connected to the rod chamber of the brake cylinder of the parking brake, the oil return port of the first reversing valve is connected to the oil inlet end of the oil return oil circuit, the working oil port of the first reversing valve being in a power-off state being in communication with the oil return port, and the working oil port of the first reversing valve being in a power-on state being in communication with the oil inlet;

[0008] a second reversing valve and an accumulator, wherein the oil inlet of the second reversing valve is connected to the accumulator, the oil outlet of the second reversing valve is connected to the oil return line, and the connection position is located between the oil inlet end of the oil return line and the damping member, the oil inlet and the oil outlet of the second reversing valve are connected in a de-energized state, and the oil inlet and the oil outlet of the second reversing valve are disconnected in a powered state;

[0009] The oil inlet circuit is connected to the oil inlet of the first reversing valve and the accumulator respectively.

[0010] Optionally, the oil inlet circuit includes:

[0011] Hydraulic pumps;

[0012] a one-way valve, wherein the oil inlet of the one-way valve is connected to the output end of the hydraulic pump;

[0013] One end of the first oil circuit is connected to the oil outlet of the one-way valve, and the other end is connected to the oil inlet of the first reversing valve. The first oil circuit is also connected to the accumulator.

[0014] Optionally, the oil inlet circuit further includes a relief valve, and the relief valve is arranged in parallel with the hydraulic pump.

[0015] Optionally, the damping member is a throttle valve.

[0016] Optionally, the first reversing valve is a proportional valve, and the parking brake system further includes a controller, which is communicatively connected to the first reversing valve and is used to control the flow path opening between the working oil port and the return oil port of the first reversing valve to gradually increase after receiving an emergency stop signal.

[0017] Optionally, the parking brake system also includes a vehicle speed detector, and the controller is communicatively connected to the vehicle speed detector and is used to control the flow path opening between the working oil port and the return oil port of the first reversing valve to gradually increase according to the vehicle speed information detected by the vehicle speed detector after receiving an emergency stop signal.

[0018] Optionally, the vehicle speed detector is a tire speed sensor.

[0019] Optionally, the first reversing valve is a two-position three-way direct-acting reversing valve.

[0020] Optionally, the second reversing valve is a two-position two-way direct-acting reversing valve.

[0021] The utility model also provides an agricultural machine, which comprises the above-mentioned parking brake system.

[0022] Through the above technical solution, the parking brake system of the present invention can be applied to agricultural machinery. When the agricultural machinery accidentally loses power during driving, resulting in a power loss in the parking brake system, the first reversing valve and the second reversing valve are both in a power-off state at the same time. The working oil port of the first reversing valve is connected to the return oil port so that the rod chamber of the brake cylinder of the parking brake is connected to the return oil circuit. At the same time, the oil inlet and oil outlet of the second reversing valve are connected so that the accumulator is connected to the return oil circuit. At this time, under the hydraulic damping action of the damping member, the rod chamber of the brake cylinder can be prevented from instantaneously releasing pressure through the return oil circuit. At the same time, the accumulator can provide hydraulic energy to the brake cylinder through the return oil circuit and the first reversing valve for a period of time, preventing the hydraulic oil in the rod chamber of the brake cylinder from flowing back, thereby avoiding the situation where the parking brake is immediately braked to lock the tire and cause a safety accident when the power is accidentally lost. Moreover, as the hydraulic energy provided by the accumulator gradually decreases, the hydraulic oil in the rod chamber of the brake cylinder will gradually and slowly flow back through the return oil line, and the parking brake will perform parking braking more smoothly and slowly, so that the agricultural machinery can be parked smoothly. That is, when the agricultural machinery loses power accidentally during driving, the parking brake system can prevent the agricultural machinery tires from locking and can make the agricultural machinery slow down more slowly and steadily until it stops. In this way, the safety factor in the event of accidental power failure is effectively further improved.

[0023] Other features and advantages of the present invention will be described in detail in the subsequent specific embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the following specific embodiments, they are used to explain the present invention but do not constitute a limitation of the present invention. In the accompanying drawings:

[0025] Figure 1 It is a structural diagram of the parking brake system in a specific embodiment of the present utility model.

[0026] Description of reference numerals:

[0027] 1 Brake cylinder 2 First reversing valve

[0028] 3 Second reversing valve 4 Accumulator

[0029] 5 Hydraulic pump 6 Check valve

[0030] 7 First oil circuit 8 Relief valve

[0031] 9 Second oil circuit 10 Damping element

[0032] 11 Third Oil Line DETAILED DESCRIPTION

[0033] The following is a detailed description of the specific embodiments of the present invention in conjunction with the accompanying drawings. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present invention and are not intended to limit the present invention.

[0034] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features therein can be combined with each other.

[0035] In the present invention, unless otherwise specified, directional words such as "up, down, top, bottom" are usually used to describe the relative positions of components in the directions shown in the drawings or in the vertical, perpendicular or gravity directions.

[0036] The present invention will be described in detail below with reference to the accompanying drawings and in combination with embodiments.

[0037] The utility model first provides a parking brake system.

[0038] In one embodiment, referring to the attached Figure 1 As shown, the parking brake system includes:

[0039] parking brake;

[0040] The oil return circuit includes a damping member 10;

[0041] The first reversing valve 2, the working oil port of the first reversing valve 2 is connected to the rod chamber of the brake cylinder 1 of the parking brake, the return oil port of the first reversing valve 2 is connected to the oil inlet end of the return oil circuit, the working oil port of the first reversing valve 2 in the de-energized state is connected to the return oil port, and the working oil port of the first reversing valve 2 in the energized state is connected to the oil inlet;

[0042] The second reversing valve 3 and the accumulator 4, the oil inlet of the second reversing valve 3 is connected to the accumulator 4, the oil outlet of the second reversing valve 3 is connected to the oil return line, and the connection position is located between the oil inlet end of the oil return line and the damping member 10. In the de-energized state, the oil inlet and the oil outlet of the second reversing valve 3 are connected, and in the energized state, the oil inlet and the oil outlet of the second reversing valve 3 are disconnected;

[0043] The oil inlet circuit is connected to the oil inlet of the first reversing valve 2 and the accumulator 4 respectively.

[0044] The parking brake system of this embodiment can be applied to agricultural machinery. When the agricultural machinery is switched to a driving gear, first reversing valve 2 is energized, and the working oil port of first reversing valve 2 is connected to the oil inlet port, thereby connecting the rod chamber of brake cylinder 1 of the parking brake to the oil inlet circuit. This configuration allows the oil inlet circuit to continuously supply hydraulic energy to brake cylinder 1 through first reversing valve 2, keeping the parking brake in the released state.

[0045] When the agricultural machinery loses power unexpectedly during driving, causing the parking brake system to lose power, the first reversing valve 2 and the second reversing valve 3 are both in a power-off state at the same time. The working oil port of the first reversing valve 2 is connected to the return oil port so that the rod chamber of the brake cylinder 1 of the parking brake is connected to the return oil circuit. At the same time, the oil inlet and oil outlet of the second reversing valve 3 are connected so that the accumulator 4 is connected to the return oil circuit. At this time, under the hydraulic damping action of the damping member 10, the rod chamber of the brake cylinder 1 can be prevented from instantaneously releasing pressure through the return oil circuit. At the same time, the accumulator 4 can provide hydraulic energy to the brake cylinder 1 through the return oil circuit and the first reversing valve 2 for a period of time, so that the rod chamber of the brake cylinder 1 maintains high pressure, preventing the hydraulic oil in the rod chamber of the brake cylinder 1 from flowing back, and avoiding the situation where the parking brake is immediately braked and the tire is locked when power is accidentally lost, thereby causing a safety accident. Moreover, as the hydraulic energy provided by the accumulator 4 gradually decreases, the hydraulic oil in the rod chamber of the brake cylinder 1 will gradually and slowly flow back through the return oil circuit, and the parking brake will perform parking braking more smoothly and slowly, so that the agricultural machinery can be parked smoothly. That is, when the agricultural machinery loses power unexpectedly, the parking brake system can prevent the agricultural machinery tires from locking while allowing the agricultural machinery to slow down more slowly and steadily until it stops. In this way, the safety factor in the event of an accidental power failure is effectively further improved.

[0046] In order to ensure that the second reversing valve 3 can lose power synchronously with the loss of power to the first reversing valve 2, the second reversing valve 3 and the first reversing valve 2 can be set in the same control circuit, or a controller can be set to communicate with the second reversing valve 3 and the first reversing valve 2 respectively. When it is determined that the first reversing valve 2 loses power, the controller will promptly control the second reversing valve 3 to lose power synchronously.

[0047] Specifically, the first reversing valve 2 can be a two-position three-way reversing valve and the valve core has a first valve position and a second valve position. In the de-energized state, the valve core of the first reversing valve 2 is in the first valve position driven by the elastic force of the spring, and the working oil port of the first reversing valve 2 is connected to the return oil port. In the energized state, the valve core of the first reversing valve 2 overcomes the elastic force of the spring under the action of the electromagnet and switches to the second valve position, and the working oil port of the first reversing valve 2 is connected to the oil inlet.

[0048] Specifically, the return oil circuit may also include a second oil circuit 9 and a third oil circuit 11. One end of the second oil circuit 9 is connected to the return oil port of the first reversing valve 2, and the other end is connected to one port of the damping element 10. One end of the third oil circuit 11 is connected to the other port of the damping element 10, and the oil outlet of the second reversing valve 3 is connected to the second oil circuit 9.

[0049] Specifically, the first reversing valve 2 and the second reversing valve 3 may be solenoid reversing valves or electric reversing valves or other valves that can be controlled electrically.

[0050] In this embodiment, the oil inlet circuit is connected to the oil inlet of the first reversing valve 2 and the accumulator 4, respectively. When the first reversing valve 2 is energized, the working oil port of the first reversing valve 2 communicates with the oil inlet. With this arrangement, when the agricultural machine is switched to a driving gear, the first reversing valve 2 is energized, and the working oil port of the first reversing valve 2 communicates with the oil inlet. This allows the accumulator 4 to simultaneously store energy when the rod chamber of the parking brake cylinder 1 is connected to the oil inlet circuit.

[0051] In actual application, the input end of the oil inlet circuit and the output end of the oil return circuit can be connected to the hydraulic oil tank to realize oil supply and oil return.

[0052] In this embodiment, the oil inlet and oil outlet of the second reversing valve 3 are disconnected when the machine is powered. This arrangement prevents some hydraulic oil in the oil inlet circuit from entering the oil return circuit through the second reversing valve 3 when the agricultural machine is switched to a driving gear.

[0053] Specifically, the second reversing valve 3 can be a two-position two-way reversing valve and the valve core has a first valve position and a second valve position. In the de-energized state, the valve core of the second reversing valve 3 is in the first valve position driven by the elastic force of the spring, and the oil inlet and oil outlet of the second reversing valve 3 are connected. In the energized state, the valve core of the second reversing valve 3 overcomes the elastic force of the spring under the action of the electromagnet and switches to the second valve position, and the oil inlet and oil outlet of the second reversing valve 3 are disconnected.

[0054] In one embodiment, the oil inlet circuit includes:

[0055] Hydraulic pump 5;

[0056] A one-way valve 6, the oil inlet of the one-way valve 6 is connected to the output end of the hydraulic pump 5;

[0057] A first oil circuit 7, one end of which is connected to the oil outlet of the one-way valve 6, and the other end of which is connected to the oil inlet of the first reversing valve 2. The first oil circuit 7 is also connected to the accumulator 4;

[0058] In actual application, the input end of the hydraulic pump 5 can be connected to the hydraulic oil tank.

[0059] In this embodiment, when the hydraulic pump 5 stops unexpectedly, the one-way valve 6 can prevent the accumulator 4 from being depressurized, and the hydraulic oil in the brake cylinder 1 from being instantly backflowed and depressurized, thereby maintaining the pressure of the brake cylinder 1 in a short period of time, and preventing the parking brake from being immediately applied and locking the tire when the hydraulic pump 5 stops.

[0060] In one embodiment, the oil inlet circuit further includes a relief valve 8, which is arranged in parallel with the hydraulic pump 5. In this arrangement, the relief valve 8 can prevent the input hydraulic pressure of the hydraulic pump 5 from being too high.

[0061] Specifically, the overflow valve 8 can be a manual adjustment structure or an electric adjustment structure.

[0062] In one embodiment, the damping member 10 is a throttle valve. In this configuration, the hydraulic damping effect is achieved through the throttling action of the throttle valve.

[0063] Of course, in other embodiments, the damping member 10 may also be a speed regulating valve or a damping valve.

[0064] In one embodiment, the first reversing valve 2 is a proportional valve, and the parking brake system also includes a controller, which is communicated with the first reversing valve 2 and is used to control the flow path opening between the working oil port and the return oil port of the first reversing valve 2 to gradually increase after receiving an emergency stop signal.

[0065] As will be appreciated, agricultural machinery is generally equipped with an emergency stop switch, which can be used to quickly shut down the agricultural machinery's engine in an emergency. At this point, the hydraulic pump 5 will also shut down simultaneously. In this embodiment, the first reversing valve 2 is configured as a proportional valve. Upon receiving an emergency stop signal generated by pressing the emergency stop switch, the controller controls the flow path opening between the working oil port and the return oil port of the first reversing valve 2 to gradually increase. With this configuration, based on the characteristics of the proportional valve, after the hydraulic pump 5 shuts down, the first reversing valve 2 can be controlled by the controller to gradually increase the flow path opening between the working oil port and the return oil port, thereby controlling the return oil speed of the brake cylinder 1 and enabling the brake cylinder 1 to release pressure more slowly. This prevents the brake cylinder 1 from releasing pressure instantly, causing the parking brake to immediately apply and lock the tires. This allows the agricultural machinery to smoothly and slowly apply the parking brake even in emergency situations.

[0066] Of course, in some other embodiments, the second reversing valve 3 may also be a servo valve.

[0067] In one embodiment, the parking brake system further includes a vehicle speed detector. The controller is communicatively connected to the vehicle speed detector and is configured to, upon receiving an emergency stop signal, gradually increase the opening of the flow path between the working oil port and the return oil port of the first reversing valve 2 based on vehicle speed information detected by the vehicle speed detector. This arrangement allows the opening of the flow path between the working oil port and the return oil port of the first reversing valve 2 to be adjusted accordingly based on the actual vehicle speed, ensuring that the braking force of the parking brake matches the vehicle speed, further improving the reliability of the smooth and gentle parking brake application of the agricultural machinery in emergency stops.

[0068] In one embodiment, the vehicle speed detector is a tire speed sensor.

[0069] In this embodiment, the vehicle speed detector determines the traveling speed of the agricultural machinery by detecting the rotation speed of the tires of the agricultural machinery.

[0070] Of course, in some other embodiments, the vehicle speed detector may also be a GPS speedometer.

[0071] The present invention also provides an agricultural machine including the parking brake system described above. The specific structure of the parking brake system is described with reference to the above embodiments. Since the present agricultural machine utilizes all of the technical solutions of all of the above embodiments, it at least has all of the beneficial effects brought about by the technical solutions of the above embodiments, and therefore, no further details will be given here.

[0072] In addition, the agricultural machinery may be, for example, a forage machine, a tractor, or the like.

[0073] In the description of this utility model, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature specified as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of this utility model, "plurality" means at least two, for example, two, three, etc., unless otherwise specifically defined.

[0074] In this utility model, unless otherwise specified or limited, the terms "installed," "connected," "connect," "fixed," etc. should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection, or communication; direct connection or indirect connection through an intermediate medium; internal communication between two elements or interaction between two elements, unless otherwise specified. For those skilled in the art, the specific meanings of the above terms in this utility model can be understood according to specific circumstances.

[0075] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and features of different embodiments or examples without contradiction.

[0076] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are illustrative and cannot be understood as limitations on the present invention. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A parking brake system, characterized in that: The parking brake system comprises: parking brake; An oil return line including a damping member (10); a first reversing valve (2), wherein a working oil port of the first reversing valve (2) is connected to a rod chamber of a brake cylinder (1) of the parking brake, a return oil port of the first reversing valve (2) is connected to an oil inlet end of the return oil circuit, the working oil port of the first reversing valve (2) in a power-off state is communicated with the return oil port, and the working oil port of the first reversing valve (2) in a power-on state is communicated with the oil inlet; a second reversing valve (3) and an accumulator (4), wherein the oil inlet of the second reversing valve (3) is connected to the accumulator (4), the oil outlet of the second reversing valve (3) is connected to the oil return line, and the connection position is located between the oil inlet end of the oil return line and the damping member (10); the oil inlet and the oil outlet of the second reversing valve (3) are connected in a power-off state, and the oil inlet and the oil outlet of the second reversing valve (3) are disconnected in a power-on state; The oil inlet circuit is connected to the oil inlet of the first reversing valve (2) and the accumulator (4) respectively.

2. The parking brake system according to claim 1, characterized in that: The oil inlet circuit includes: Hydraulic pump (5); a one-way valve (6), wherein the oil inlet of the one-way valve (6) is connected to the output end of the hydraulic pump (5); A first oil circuit (7) has one end connected to the oil outlet of the one-way valve (6) and the other end connected to the oil inlet of the first reversing valve (2). The first oil circuit (7) is also connected to the accumulator (4).

3. The parking brake system according to claim 2, characterized in that: The oil inlet circuit further comprises a relief valve (8), and the relief valve (8) is arranged in parallel with the hydraulic pump (5).

4. The parking brake system according to claim 1, characterized in that: The damping member (10) is a throttle valve.

5. The parking brake system according to claim 1 or 2, characterized in that: The first reversing valve (2) is a proportional valve. The parking brake system further comprises a controller, which is in communication with the first reversing valve (2) and is used to control the flow path opening between the working oil port and the return oil port of the first reversing valve (2) to gradually increase after receiving an emergency stop signal.

6. The parking brake system according to claim 5, characterized in that: The parking brake system further comprises a vehicle speed detector, the controller being in communication with the vehicle speed detector and being used to control the flow path opening between the working oil port and the return oil port of the first reversing valve (2) to gradually increase according to the vehicle speed information detected by the vehicle speed detector after receiving an emergency stop signal.

7. The parking brake system according to claim 6, characterized in that: The vehicle speed detector is a tire speed sensor.

8. The parking brake system according to claim 1, characterized in that: The first reversing valve (2) is a two-position three-way direct-acting reversing valve.

9. The parking brake system according to claim 1, characterized in that: The second reversing valve (3) is a two-position two-way direct-acting reversing valve.

10. An agricultural machine, characterized in that: The agricultural machine comprises a parking brake system according to any one of claims 1 to 9.

Images