Dual power brake system and agricultural machinery equipment

Abstract

The present invention relates to a dual power brake system and agricultural machinery equipment, wherein a dual power brake system includes a pressure reducing valve group and a service brake reversing valve group, the oil inlet of the pressure reducing valve group is connected to the pressure oil port of the brake pressure reducing valve for inputting pressure oil, the oil return port of the pressure reducing valve group is connected to the valve oil return port T for connecting to the oil tank, and the two-way oil port of the pressure reducing valve group is connected to the hydraulic trailer brake pilot oil port B, the two-way oil port of the pressure reducing valve group is also connected to the service brake reversing valve group, and the service brake reversing valve group is connected to the service brake control oil port. The technical solution of the present invention can improve the technical problem that the existing tractor increases the braking force by increasing the displacement of the master cylinder, resulting in the intermediate connecting rod force becoming heavier and the driver's feeling becoming worse, and solve the demand for large-displacement braking to achieve hydraulic power braking.

Description

Technical Field

[0001] The present invention relates to the technical field of agricultural machinery and equipment, and in particular to a dual power brake system and agricultural machinery and equipment. Background Art

[0002] With the upgrade of tractor horsepower, the demand for tractor braking is increasing, especially in some countries and regions where the braking reduction ratio is larger than other regions, and the braking force must be increased. In this regard, the current technical solution is to increase the displacement of the brake master cylinder for the problem of a certain cylinder capacity. This method leads to a larger and larger volume, heavier intermediate connecting rod force, and worse driver experience. Summary of the invention

[0003] The present invention aims to solve the technical problem that the existing tractors increase the braking force by increasing the main cylinder displacement, which results in the intermediate connecting rod force becoming heavier and the driver's feeling becoming worse. The present invention provides a dual-power braking system and agricultural machinery equipment, solves the demand for large-displacement braking, and realizes hydraulic power braking.

[0004] The technical solution of the present invention to solve the above technical problems is as follows:

[0005] On the one hand, the present invention provides a dual-power brake system, including a pressure reducing valve group and a service brake reversing valve group, the oil inlet of the pressure reducing valve group is connected to the pressure oil port of the brake pressure reducing valve for inputting pressure oil, the oil return port of the pressure reducing valve group is connected to the valve return oil port T for connecting to the oil tank, and the two-way oil port of the pressure reducing valve group is connected to the hydraulic trailer brake pilot oil port B, the two-way oil port of the pressure reducing valve group is also connected to the service brake reversing valve group, and the service brake reversing valve group is connected to the service brake control oil port.

[0006] The beneficial effects of the present invention are as follows: by arranging a pressure reducing valve group and a service brake reversing valve group, the oil in the oil cylinder is continuously outputted, and when the service brake pedal is stepped on, the pressure reducing valve group is used to proportionally reduce the pressure of the oil input through the pressure oil port of the brake pressure reducing valve, so as to control the braking pressure and improve safety; at the same time, when the service brake pedal is stepped on, the pressure oil is introduced into the service brake control oil port through the service brake reversing valve group to perform service braking, so as to meet the demand for large-displacement braking, realize hydraulic power braking, and improve the technical problem that the existing tractors increase the braking force by increasing the displacement of the master cylinder, resulting in the pedal force becoming heavier and the driver's feeling becoming worse.

[0007] Based on the above technical solution, the present invention can also be improved as follows.

[0008] Further, the pressure reducing valve group includes a rear axle brake pressure reducing valve, the service brake reversing valve group includes a left service brake reversing valve, the brake pressure reducing valve pressure oil port includes a rear axle brake pressure reducing valve pressure oil port A1, and the service brake control oil port includes a left service brake control oil port R2; the oil inlet 2a of the rear axle brake pressure reducing valve is connected to the rear axle brake pressure reducing valve pressure oil port A1, the two-way oil port 2b of the rear axle brake pressure reducing valve is simultaneously connected to the hydraulic trailer brake pilot oil port B and the oil port 1a of the left service brake reversing valve, the oil return port 2c of the rear axle brake pressure reducing valve is connected to the valve oil return port T; the oil port 1c of the left service brake reversing valve is connected to the left service brake control oil port R2.

[0009] The beneficial effect of adopting the above further scheme is: the rear axle brake reducing valve is used to proportionally reduce the pressure of the oil input through the pressure oil port A1 of the rear axle brake reducing valve, so as to control the braking pressure and improve safety. At the same time, the pressure oil is introduced into the left service brake control oil port R2 through the left service brake reversing valve to perform left service braking, so as to solve the large-displacement braking demand, realize hydraulic power braking, and improve the technical problem that the existing tractors increase the braking force by increasing the master cylinder displacement, resulting in heavier pedal force and worse driver experience.

[0010] Further, the pressure reducing valve group also includes a front axle brake pressure reducing valve, the service brake reversing valve group also includes a right service brake reversing valve, the brake pressure reducing valve pressure oil port includes a front axle brake pressure reducing valve pressure oil port A2, and the service brake control oil port includes a right service brake control oil port R1; the oil inlet 3a of the front axle brake pressure reducing valve is connected to the front axle brake pressure reducing valve pressure oil port A2, the two-way oil port 3b of the front axle brake pressure reducing valve is connected to the hydraulic trailer brake pilot oil port B, and the oil return port 3c of the front axle brake pressure reducing valve is connected to the valve oil return port T; the oil port 4c of the right service brake reversing valve is connected to the right service brake control oil port R1; and the two-way oil port 2b of the rear axle brake pressure reducing valve is also connected to the oil port 4a of the right service brake reversing valve, and the oil port 4a of the right service brake reversing valve is also connected to the hydraulic trailer brake pilot oil port B.

[0011] The beneficial effect of adopting the above further scheme is: during braking, the front axle brake reducing valve is used to proportionally reduce the pressure of the oil input through the pressure oil port A2 of the front axle brake reducing valve, so as to control the braking pressure and improve safety. At the same time, the pressure oil is introduced into the right service brake control oil port R1 through the right service brake reversing valve to perform right service braking, so as to solve the demand for large-displacement braking, realize hydraulic power braking, and improve the technical problem that the existing tractors increase the braking force by increasing the master cylinder displacement, resulting in heavier pedal force and worse driver experience.

[0012] Furthermore, it also includes a solenoid valve, the two-way oil port 2b of the rear axle brake pressure reducing valve is connected to the oil port 5a of the solenoid valve, the oil port 5b of the solenoid valve is simultaneously connected to the oil port 1b of the left service brake reversing valve and the oil port 4b of the right service brake reversing valve, the oil port 5c of the solenoid valve is connected to the valve oil return port T, when the vehicle speed reaches a preset vehicle speed threshold, the solenoid valve is used to control the two-way oil port 2b of the rear axle brake pressure reducing valve to be simultaneously connected to the oil port 1b of the left service brake reversing valve and the oil port 4b of the right service brake reversing valve.

[0013] The beneficial effect of adopting the above further scheme is: when the vehicle speed reaches the preset vehicle speed threshold, the solenoid valve is de-energized and only the left service brake reversing valve is controlled to start, the two-way oil port 2b of the rear axle brake reducing valve and the two-way oil port 3b of the front axle brake reducing valve are connected, and the pressure oil of the pressure oil port A1 of the rear axle brake reducing valve can act on the right service brake control oil port R1 and the left service brake control oil port R2 at the same time, realizing simultaneous left and right bilateral braking.

[0014] Furthermore, it also includes a hydraulically controlled reversing valve, the oil port 6a of the hydraulically controlled reversing valve is connected to the hydraulic trailer brake pilot oil port B, the oil port 6b of the hydraulically controlled reversing valve is connected to the two-way oil port 3b of the front axle brake pressure reducing valve, and the hydraulically controlled reversing valve controls the oil port 6a and the oil port 6b to be connected, so that the two-way oil port 3b of the front axle brake pressure reducing valve is connected to the hydraulic trailer brake pilot oil port B, and the oil port 6c of the hydraulically controlled reversing valve is connected to the valve oil return port T.

[0015] The beneficial effect of adopting the above further scheme is: by setting a hydraulically controlled reversing valve, when unilateral braking is performed, the front axle is not braked, and when bilateral braking is performed, the front axle has braking pressure; the pressure oil starts from the left service brake control oil port R2 and is conducted to the hydraulic trailer brake pilot oil port B.

[0016] Furthermore, the oil port 1c of the left service brake reversing valve and the oil port 4c of the right service brake reversing valve are also simultaneously connected to the hydraulically controlled reversing valve.

[0017] The beneficial effect of adopting the above-mentioned further scheme is: to enable the braking system to adjust the pressure according to actual needs, to ensure a smooth and reliable braking process; that is, part of the pressure oil derived from the oil port 1c of the left service brake reversing valve and the oil port 4c of the right service brake reversing valve can be respectively introduced into the left and right sides of the hydraulically controlled reversing valve, and the left and right pressures of the hydraulically controlled reversing valve are the same.

[0018] Furthermore, a shuttle valve is included, through which the oil port 6a of the hydraulically controlled reversing valve and the two-way oil port 2b of the rear axle brake pressure reducing valve are both connected to the hydraulic trailer brake pilot oil port B.

[0019] The beneficial effect of adopting the above further scheme is that when braking in service, the front axle brake and the rear axle brake are set to the maximum pressure, that is, the pressure oil from the oil port 6a of the hydraulically controlled reversing valve and the two-way oil port 2b of the rear axle brake pressure reducing valve are compared and selected to perform trailer brake pilot control.

[0020] Furthermore, the shuttle valve is also connected to the front axle service brake oil port F, the hydraulically controlled reversing valve control oil port 6a and oil port 6b are connected, and the two-way oil port 3b of the front axle brake pressure reducing valve is connected to the front axle service brake oil port F through the oil port 6a of the hydraulically controlled reversing valve.

[0021] The beneficial effect of adopting the above further scheme is that when the rear axle brake reducing valve and the front axle brake reducing valve are braked at the same time, the pressure oil at the pressure oil port A2 of the front axle brake reducing valve passes through the front axle brake reducing valve and then reaches the front axle service brake oil port F through the hydraulically controlled reversing valve. At this time, the left and right sides are braked simultaneously, and the front axle is braked, and the hydraulic trailer brake has a pilot pressure.

[0022] Furthermore, the rear axle brake pressure reducing valve and the front axle brake pressure reducing valve are both connected with an intermediate connecting rod, and the left service brake reversing valve and the right service brake reversing valve are both provided with pedals, and the intermediate connecting rod is arranged in linkage with the pedals.

[0023] The beneficial effect of adopting the above further solution is that when only the left service brake reversing valve is stepped on, the two-way oil port 2b of the rear axle brake pressure reducing valve and the two-way oil port 3b of the front axle brake pressure reducing valve are connected through the middle connecting rod.

[0024] On the other hand, the present invention provides an agricultural mechanical equipment, comprising the dual power braking system. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 is a structural diagram of the dual power brake system of the present invention;

[0026] Figure 2 It is a structural diagram of the working condition 1 of the dual power brake system of the present invention;

[0027] Figure 3 It is a structural diagram of the working condition 2 of the dual power brake system of the present invention;

[0028] Figure 4 It is a structural diagram of working condition 3 of the dual power brake system of the present invention;

[0029] Figure 5 It is a structural diagram of working condition 4 of the dual power brake system of the present invention;

[0030] Figure 6 It is a structural diagram of working condition 5 of the dual power brake system of the present invention.

[0031] In the accompanying drawings, Figures 2 to 6 The thick solid line with an arrow in the middle indicates the direction of the pressure oil, and the thin solid line with an arrow indicates the direction of the pressure oil return.

[0032] In the accompanying drawings, the components represented by the reference numerals are listed as follows:

[0033] 1. Left service brake reversing valve; 2. Rear axle brake pressure reducing valve; 3. Front axle brake pressure reducing valve; 4. Right service brake reversing valve; 5. Solenoid valve; 6. Hydraulic control reversing valve; 7. Shuttle valve; 8. Intermediate connecting rod. DETAILED DESCRIPTION

[0034] The principles and features of the present invention are described below. The examples given are only used to explain the present invention and are not used to limit the scope of the present invention.

[0035] On the one hand, the present invention provides a dual power braking system, as described in detail below.

[0036] Example 1

[0037] like Figure 1 A dual-power brake system includes a pressure reducing valve group and a service brake reversing valve group, the oil inlet of the pressure reducing valve group is connected to the pressure oil port of the brake pressure reducing valve for inputting pressure oil, the oil return port of the pressure reducing valve group is connected to the valve return oil port T for connecting to the oil tank, and the two-way oil port of the pressure reducing valve group is connected to the hydraulic trailer brake pilot oil port B, the two-way oil port of the pressure reducing valve group is also connected to the service brake reversing valve group, and the service brake reversing valve group is connected to the service brake control oil port.

[0038] The beneficial effects of this embodiment are as follows: by providing a pressure reducing valve group and a service brake reversing valve group, the oil in the oil cylinder is continuously outputted, and when the service brake pedal is stepped on, the pressure reducing valve group is used to proportionally reduce the pressure of the oil input through the pressure oil port of the brake pressure reducing valve, thereby controlling the braking pressure and improving safety; at the same time, when the service brake pedal is stepped on, the pressure oil is introduced into the service brake control oil port through the service brake reversing valve group for service braking, thereby solving the demand for large-displacement braking, realizing hydraulic power braking, and improving the technical problem that the existing tractors increase the braking force by increasing the displacement of the master cylinder, resulting in the pedal force becoming heavier and the driver's feeling becoming worse.

[0039] Example 2

[0040] like Figure 1 and Figure 2On the basis of Example 1, the pressure reducing valve group includes a rear axle brake pressure reducing valve 2, the service brake reversing valve group includes a left service brake reversing valve 1, the brake pressure reducing valve pressure oil port includes a rear axle brake pressure reducing valve pressure oil port A1, and the service brake control oil port includes a left service brake control oil port R2; the oil inlet 2a of the rear axle brake pressure reducing valve 2 is connected to the rear axle brake pressure reducing valve pressure oil port A1, the two-way oil port 2b of the rear axle brake pressure reducing valve 2 is simultaneously connected to the hydraulic trailer brake pilot oil port B and the oil port 1a of the left service brake reversing valve, the oil return port 2c of the rear axle brake pressure reducing valve is connected to the valve oil return port T; the oil port 1c of the left service brake reversing valve is connected to the left service brake control oil port R2.

[0041] The beneficial effect of adopting the preferred scheme in the above embodiment is that when the service brake pedal is stepped on, the rear axle brake reducing valve 2 is used to proportionally reduce the pressure of the oil input through the rear axle brake reducing valve pressure oil port A1 to control the brake pressure and improve safety. At the same time, when the left service brake pedal is stepped on, the pressure oil is introduced into the left service brake control oil port R2 through the left service brake reversing valve 1 to perform left service braking, so as to meet the demand for large-displacement braking, realize hydraulic power braking, and improve the technical problem that the existing tractors increase the braking force by increasing the master cylinder displacement, resulting in the pedal force becoming heavier and the driver's feeling becoming worse.

[0042] Among them, the left service brake reversing valve 1 is a two-position three-way control valve. When the left brake pedal is stepped on, the valve reverses, the oil port 1a of the left service brake reversing valve 1 is connected with the oil port 1c of the left service brake reversing valve, and the oil port 1b of the left service brake reversing valve is closed, and the pressure oil is introduced into the left service brake control oil port R2 to perform left service braking; when the pedal is not stepped on, the oil port 1b of the left service brake reversing valve is connected with the oil port 1c of the left service brake reversing valve, and the oil port 1a of the left service brake reversing valve 1 is closed.

[0043] In the initial position, there is no braking, and the pedal is not pressed at this time. The pressure oil at the pressure oil port A1 of the rear axle brake reducing valve is cut off at the inlet 2a of the rear axle brake reducing valve 2; at this time, all oil ports are not braked.

[0044] Example 3

[0045] like Figure 1On the basis of embodiments 1 and 2, the pressure reducing valve group further includes a front axle brake pressure reducing valve 3, the service brake reversing valve group further includes a right service brake reversing valve 4, the brake pressure reducing valve pressure oil port includes a front axle brake pressure reducing valve pressure oil port A2, and the service brake control oil port includes a right service brake control oil port R1; the oil inlet 3a of the front axle brake pressure reducing valve 3 is connected to the front axle brake pressure reducing valve pressure oil port A2, the two-way oil port 3b of the front axle brake pressure reducing valve 3 is connected to the hydraulic trailer brake pilot oil port B, and the oil return port 3c of the front axle brake pressure reducing valve 3 is connected to the valve oil return port T; the oil port 4c of the right service brake reversing valve 4 is connected to the right service brake control oil port R1; and the two-way oil port 2b of the rear axle brake pressure reducing valve 2 is also connected to the oil port 4a of the right service brake reversing valve 4, and the oil port 4a of the right service brake reversing valve 4 is also connected to the hydraulic trailer brake pilot oil port B.

[0046] The beneficial effect of adopting the preferred scheme in the above embodiment is that, when not braking, the pressure oil entering from the rear axle brake reducing valve pressure oil port A1 and the front axle brake reducing valve pressure oil port A2 is respectively terminated at the oil inlet 2a of the rear axle brake reducing valve 2 and the oil inlet 3a of the front axle brake reducing valve 3; at this time, all oil ports are not braking; when braking, when stepping on the service brake pedal, the front axle brake reducing valve 3 is used to proportionally reduce the pressure of the oil input through the front axle brake reducing valve pressure oil port A2 to control the braking pressure and improve safety. At the same time, when stepping on the right service brake pedal, the pressure oil is introduced into the right service brake control oil port R1 through the right service brake reversing valve 4 to perform right service braking, so as to solve the large-displacement braking demand, realize hydraulic power braking, and improve the technical problem that the existing tractors increase the braking force by increasing the master cylinder displacement, resulting in the pedal force becoming heavier and the driver's feeling becoming worse.

[0047] When the left pedal or the right pedal is pressed, the oil inlet 2a of the rear axle brake reducing valve 2 and the two-way oil port 2b of the rear axle brake reducing valve 2 are connected, and the pressure of the two-way oil port 2b of the rear axle brake reducing valve 2 is proportional to the displacement of the reducing valve core. The greater the displacement, the greater the pressure, and the excess oil is returned to the valve return oil port T through the return oil port 2c of the rear axle brake reducing valve 2.

[0048] When the left pedal or the right pedal is pressed, the oil inlet 3a of the front axle brake reducing valve 3 and the two-way oil port 3b of the front axle brake reducing valve 3 are connected, and the pressure of the two-way oil port 3b of the front axle brake reducing valve 3 is proportional to the displacement of the reducing valve valve core. The greater the displacement, the greater the pressure, and the excess oil is returned to the valve return oil port T through the return oil port 3c of the front axle brake reducing valve 3.

[0049] The right service brake reversing valve 4 is a two-position three-way control valve. When the right brake pedal is stepped on, the valve is reversed, the oil port 4a of the right service brake reversing valve 4 is connected with the oil port 4c of the right service brake reversing valve 4, and the oil port 4b of the right service brake reversing valve 4 is closed, and the pressure oil is introduced into the right service brake control oil port R1 to perform left service braking; when the pedal is not stepped on, the oil port 4b of the right service brake reversing valve 4 is connected with the oil port 4c of the right service brake reversing valve 4, and the oil port 4a of the right service brake reversing valve 4 is closed.

[0050] Example 4

[0051] like Figure 1 and Figure 3 On the basis of embodiments 1-3, the dual power brake system further includes a solenoid valve 5, the two-way oil port 2b of the rear axle brake pressure reducing valve 2 is connected to the oil port 5a of the solenoid valve 5, the oil port 5b of the solenoid valve 5 is simultaneously connected to the oil port 1b of the left service brake reversing valve 1 and the oil port 4b of the right service brake reversing valve 4, the oil port 5c of the solenoid valve 5 is connected to the valve return oil port T, when the vehicle speed reaches a preset vehicle speed threshold, the solenoid valve 5 is used to control the two-way oil port 2b of the rear axle brake pressure reducing valve 2 to be simultaneously connected to the oil port 1b of the left service brake reversing valve 1 and the oil port 4b of the right service brake reversing valve 4.

[0052] The beneficial effect of adopting the preferred scheme in the above embodiment is that when the vehicle speed reaches the preset vehicle speed threshold, the solenoid valve 5 is de-energized and only the left service brake reversing valve 1 is controlled to start, the two-way oil port 2b of the rear axle brake reducing valve 2 and the two-way oil port 3b of the front axle brake reducing valve 3 are connected, and the pressure oil in the pressure oil port A1 of the rear axle brake reducing valve can act on the right service brake control oil port R1 and the left service brake control oil port R2 at the same time, realizing simultaneous left and right bilateral braking.

[0053] As a specific solution of the above embodiment, the preset vehicle speed threshold may be preset to 20-40 km / h, such as 40 km / h.

[0054] In the prior art, as the tractor's driving speed continues to increase, the tractor's unilateral braking function becomes more and more dangerous when driving at high speed. Currently, some technical solutions are to manually install a locking device to ensure that unilateral braking does not occur. However, when unilateral braking is required, the locking device must be manually released, and the steps are very cumbersome.

[0055] For the above problem, in this embodiment, when the vehicle speed is higher than the threshold value (such as 40km / h), the solenoid valve 5 is not energized, and when only the left pedal is pressed, the oil path flows as follows: Figure 3At this time, the pressure oil at the pressure port A1 of the rear axle brake pressure reducing valve passes through the rear axle brake pressure reducing valve 2, reaches the solenoid valve 5, and then changes direction through the left service brake reversing valve 1, acting on the left service brake control oil port R2. At the same time, the pressure oil passes through the right service brake reversing valve 4, reaches the right service brake control oil port R1, and then reaches port B. Although only the left pedal is stepped on at this time, the left and right brakes are applied at the same time, and there is pressure oil at the hydraulic trailer brake pilot oil port B.

[0056] Through the above scheme, the solenoid valve 5 is a two-position three-way solenoid valve, and its function is to lose power when the vehicle speed reaches a threshold value (such as 40km / h), the oil port 5a of the solenoid valve 5 and the oil port 5b of the solenoid valve 5 are connected, the oil port 5c of the solenoid valve 5 is closed, and the unilateral braking function is automatically switched to bilateral braking; when the vehicle speed is lower than the threshold value (such as 40km / h), it is energized, the oil port 5b of the solenoid valve 5 and the oil port 5c of the solenoid valve 5 are connected, the oil port 5a of the solenoid valve 5 is closed, and the unilateral braking function is restored.

[0057] Example 5

[0058] like Figure 1 On the basis of embodiments 1-4, the dual-power brake system further includes a hydraulically controlled reversing valve 6, the oil port 6a of the hydraulically controlled reversing valve 6 is connected to the hydraulic trailer brake pilot oil port B, the oil port 6b of the hydraulically controlled reversing valve 6 is connected to the two-way oil port 3b of the front axle brake pressure reducing valve 3, and the hydraulically controlled reversing valve 6 controls the oil port 6a and the oil port 6b to be connected so that the two-way oil port 3b of the front axle brake pressure reducing valve 3 is connected to the hydraulic trailer brake pilot oil port B, and the oil port 6c of the hydraulically controlled reversing valve 6 is connected to the valve return oil port T.

[0059] The beneficial effect of adopting the preferred solution in the above embodiment is that by setting the hydraulically controlled reversing valve 6, when unilateral braking is performed, the front axle is not braked, and when bilateral braking is performed, the front axle has braking pressure; the pressure oil starts from the left service brake control oil port R2 and is conducted to the hydraulic trailer brake pilot oil port B.

[0060] The hydraulically controlled reversing valve 6 can adopt a three-position three-way hydraulically controlled reversing valve. When there is pressure in the left service brake control oil port R2 and there is no pressure in the right service brake control oil port R1, the valve core is at the far left, that is, the oil port 6a of the hydraulically controlled reversing valve 6 and the oil port 6b of the hydraulically controlled reversing valve 6 are connected, and the oil port 6c of the hydraulically controlled reversing valve 6 is closed; when there is pressure in both the left service brake control oil port R2 and the right service brake control oil port R1, the valve core is in the middle position, that is, the oil port 6a of the hydraulically controlled reversing valve 6 and the oil port 6b of the hydraulically controlled reversing valve 6 are connected, and the oil port 6c of the hydraulically controlled reversing valve 6 is closed; when there is no pressure in the left service brake control oil port R2 and there is pressure in the right service brake control oil port R1, the valve core is at the far right, that is, the oil port 6a of the hydraulically controlled reversing valve 6 and the oil port 6c of the hydraulically controlled reversing valve 6 are connected, and the oil port 6b of the hydraulically controlled reversing valve 6 is closed.

[0061] On the basis of the above-mentioned embodiment 4, when the pressure oil passes through the right service brake reversing valve 4 and reaches the right service brake control oil port R1, it reaches the B port through the hydraulic control reversing valve 6.

[0062] Example 6

[0063] like Figure 1 On the basis of Embodiments 1-5, the oil port 1c of the left service brake reversing valve 1 and the oil port 4c of the right service brake reversing valve 4 are also connected to the hydraulically controlled reversing valve 6 at the same time.

[0064] The beneficial effect of adopting the preferred solution in the above embodiment is that the brake system can adjust the pressure according to actual needs to ensure a smooth and reliable braking process. That is, part of the pressure oil derived from the oil port 1c of the left service brake reversing valve 1 and the oil port 4c of the right service brake reversing valve 4 can be respectively introduced into the left and right sides of the hydraulic control reversing valve 6, and the left and right pressures of the hydraulic control reversing valve 6 are the same.

[0065] Example 7

[0066] like Figure 1 On the basis of embodiments 1-6, the dual power brake system further includes a shuttle valve 7, and the oil port 6a of the hydraulically controlled reversing valve 6 and the two-way oil port 2b of the rear axle brake pressure reducing valve 2 are both connected to the hydraulic trailer brake pilot oil port B through the shuttle valve 7.

[0067] The beneficial effect of adopting the preferred scheme in the above embodiment is that when the vehicle is braked, the front axle brake and the rear axle brake are set to the maximum pressure, that is, the pressure oil from the oil port 6a of the hydraulically controlled reversing valve 6 and the two-way oil port 2b of the rear axle brake pressure reducing valve 2 are compared and selected to perform trailer brake pilot control.

[0068] Based on the above embodiment 5, when the pressure oil passes through the right service brake reversing valve 4 and reaches the right service brake control oil port R1, it reaches the shuttle valve 7 through the hydraulic control reversing valve 6 and then reaches the hydraulic trailer brake pilot oil port B.

[0069] In the prior art, when the tractor needs to brake the front axle, the current technical solution can only be an external reverse shuttle valve, and the pipeline is very complicated. And if the tractor has the function of hydraulic trailer braking, the current technical solution is only an external shuttle valve, which makes the pipeline of the whole vehicle bloated.

[0070] In the embodiment of the present invention, the shuttle valve 7 is arranged between the hydraulically controlled reversing valve 6 and the hydraulic trailer brake pilot oil port B, which realizes hydraulic braking while simplifying the pipeline.

[0071] Example 8

[0072] like Figure 1On the basis of Examples 1-7, the shuttle valve 7 is also connected to the front axle service brake oil port F, the hydraulically controlled reversing valve 6 controls the oil port 6a and the oil port 6b to be connected, and the two-way oil port 3b of the front axle brake pressure reducing valve 3 is connected to the front axle service brake oil port F through the oil port 6a of the hydraulically controlled reversing valve 6.

[0073] The beneficial effect of adopting the preferred scheme in the above embodiment is that when the rear axle brake reducing valve 2 and the front axle brake reducing valve 3 are braked at the same time, the pressure oil at the pressure oil port A2 of the front axle brake reducing valve passes through the front axle brake reducing valve 3 and then reaches the front axle service brake oil port F through the hydraulically controlled reversing valve 6. At this time, the left and right sides are braked simultaneously, and the front axle is braked, and the hydraulic trailer brake has a pilot pressure.

[0074] Example 9

[0075] like Figure 1 On the basis of embodiments 1-8, the rear axle brake pressure reducing valve 2 and the front axle brake pressure reducing valve 3 are simultaneously connected with the intermediate connecting rod 8, and the left service brake reversing valve 1 and the right service brake reversing valve 4 are both provided with pedals linked with the intermediate connecting rod 8.

[0076] The beneficial effect of adopting the preferred solution in the above embodiment is that when only the left service brake reversing valve is stepped on, the two-way oil port 2b of the rear axle brake pressure reducing valve and the two-way oil port 3b of the front axle brake pressure reducing valve are connected through the middle connecting rod 8.

[0077] The working conditions of the dual power brake system of the present invention are described in detail below.

[0078] Working condition 1: Initial position, the vehicle is not braking, the pedal is not pressed, and the oil path is as follows Figure 2 In the figure, the thick solid line with arrow indicates the direction of pressure oil, and the thin solid line with arrow indicates the direction of pressure oil return. The rear axle brake pressure reducing valve 2 and the front axle brake pressure reducing valve 3 are not opened, and the pressure oil in the pressure oil port A1 of the rear axle brake pressure reducing valve and the pressure oil port A2 of the front axle brake pressure reducing valve are cut off at the oil inlet 2a of the rear axle brake pressure reducing valve 2 and the oil inlet 3a of the front axle brake pressure reducing valve 3; at this time, all oil ports are not braked, and the right service brake control oil port R1, the left service brake control oil port R2, the front axle service brake oil port F and the hydraulic trailer brake pilot oil port B are all without pressure.

[0079] Working condition 2: The vehicle speed is higher than the threshold (such as 40km / h), the speed sensor transmits the speed signal to the controller, and the controller controls the solenoid valve 5 to be de-energized. When only the left pedal is pressed, the middle connecting rod 8 connects the two-way oil port 2b of the rear axle brake pressure reducing valve 2 and the two-way oil port 3b of the front axle brake pressure reducing valve 3. The oil path is as follows: Figure 3In the figure, the thick solid line with arrow indicates the direction of pressure oil, and the thin solid line with arrow indicates the direction of pressure oil return. Starting from the rear axle brake pressure reducing valve pressure oil port A1, it is connected to the right service brake control oil port R1, the left service brake control oil port R2 and the hydraulic trailer brake pilot oil port B. Since the left and right valve core pressures of the hydraulic control reversing valve 6 are the same, starting from the front axle brake pressure reducing valve pressure oil port A2, it is connected to the front axle service brake oil port F. At this time, the right service brake control oil port R1, the left service brake control oil port R2, the front axle service brake oil port F and the hydraulic trailer brake pilot oil port B all have pressure, forming bilateral control, front axle control and trailer brake pilot control. The brake pressure is controlled in proportion to the pedal stroke. The greater the pedal stroke, the greater the brake pressure.

[0080] The vehicle speed is detected by a speed sensor and the signal is transmitted to a controller. The controller controls the solenoid valve 5, which is a conventional technical means in the art and will not be elaborated in detail here.

[0081] Working condition 3: The vehicle speed is lower than the threshold (such as 40km / h), the speed sensor transmits the speed signal to the controller, and the controller controls the solenoid valve 5 to be energized. When only the left pedal is pressed, the middle connecting rod 8 connects the two-way oil port 2b of the rear axle brake pressure reducing valve 2 and the two-way oil port 3b of the front axle brake pressure reducing valve 3. The oil path is as follows: Figure 4 In the figure, the thick solid line with arrow indicates the direction of pressure oil, and the thin solid line with arrow indicates the direction of pressure oil return. Starting from the pressure oil port A1 of the rear axle brake pressure reducing valve, it is connected to the left service brake control oil port R2 and the hydraulic trailer brake pilot oil port B. Since there is pressure on the left side of the valve core of the hydraulic control reversing valve 6 and no pressure on the right side, the valve core of the hydraulic control reversing valve 6 is at the leftmost position (on the contrary, if only the right side is stepped on, the valve core of the hydraulic control reversing valve 6 is at the rightmost position), and the pressure of the pressure oil port A2 of the front axle brake pressure reducing valve cannot be connected to the front axle service brake oil port F. At this time, there is pressure in the left service brake control oil port R2 and the hydraulic trailer brake pilot oil port B, while there is no pressure in the right service brake control oil port R1 and the front axle service brake oil port F. Only the pressure of the left unilateral brake and the hydraulic trailer brake pilot control brake is proportional to the pedal stroke. The greater the pedal stroke, the greater the brake pressure.

[0082] Working condition 4: The vehicle speed is lower than the threshold (such as 40km / h), the speed sensor transmits the speed signal to the controller, and the controller controls the solenoid valve 5 to be energized. When the left and right brake pedals are pressed at the same time, the oil path flows as follows: Figure 5In the figure, the thick solid line with arrow indicates the direction of pressure oil, and the thin solid line with arrow indicates the direction of pressure oil return. At this time, the middle connecting rod 8 drives the two-way oil port 2b of the rear axle brake pressure reducing valve 2 and the two-way oil port 3b of the front axle brake pressure reducing valve 3 to be connected, starting from the pressure oil port A1 of the rear axle brake pressure reducing valve, it is connected to the right service brake control oil port R1, the left service brake control oil port R2 and the hydraulic trailer brake pilot oil port B. Since the valve core of the hydraulic control reversing valve 6 has the same pressure on the left and right, the valve core of the hydraulic control reversing valve 6 is in the middle position, so starting from the pressure oil port A2 of the front axle brake pressure reducing valve, it is connected to the front axle service brake oil port F. At this time, the right service brake control oil port R1, the left service brake control oil port R2, the front axle service brake oil port F and the hydraulic trailer brake pilot oil port B all have pressure, forming bilateral control, front axle control and trailer brake pilot control. The brake pressure is proportional to the pedal stroke. The greater the pedal stroke, the greater the brake pressure.

[0083] Working condition 5: The vehicle speed is higher than the threshold (such as 40km / h), the speed sensor transmits the speed signal to the controller, and the controller controls the solenoid valve 5 to be de-energized. When the left and right brake pedals are pressed at the same time, the middle connecting rod 8 connects the two-way oil port 2b of the rear axle brake pressure reducing valve 2 and the two-way oil port 3b of the front axle brake pressure reducing valve 3. The oil path is as follows: Figure 6 In the figure, the thick solid line with arrow indicates the direction of pressure oil, and the thin solid line with arrow indicates the direction of pressure oil return. Starting from the pressure oil port A1 of the rear axle brake pressure reducing valve, it is connected to the right service brake control oil port R1, the left service brake control oil port R2 and the hydraulic trailer brake pilot oil port B. Since the valve core of the hydraulic control reversing valve 6 has the same pressure on the left and right sides, the valve core of the hydraulic control reversing valve 6 is in the middle position. Starting from the pressure oil port A2 of the front axle brake pressure reducing valve, it is connected to the front axle service brake oil port F. At this time, the right service brake control oil port R1, the left service brake control oil port R2, the front axle service brake oil port F and the hydraulic trailer brake pilot oil port B all have pressure, forming bilateral control, front axle control and trailer brake pilot control. The brake pressure is controlled in proportion to the pedal stroke. The greater the pedal stroke, the greater the brake pressure.

[0084] By adopting the above solution, 1. the demand for large-displacement braking is solved and hydraulic power braking is realized;

[0085] 2. When the vehicle speed is higher than the threshold of 40km / h, the unilateral braking function automatically switches to the bilateral braking function, and when the threshold is lower than 40km / h, the unilateral braking function automatically returns to the unilateral braking function;

[0086] 3. While providing rear axle braking, it can also provide front axle braking to increase braking force;

[0087] 4. When the tractor has hydraulic trailer brake function, pilot control pressure can be provided.

[0088] On the other hand, the present invention provides an agricultural mechanical equipment, as described in detail below.

[0089] Example 10

[0090] An agricultural mechanical equipment includes the dual power braking system described in Examples 1-9.

[0091] Agricultural machinery and equipment can be tractors, harvesters, and harvesters, etc.

[0092] In the description of the present invention, it is to be understood that the terms “center”, “longitudinal”, “lateral”, “length”, “width”, “thickness”, “up”, “down”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “clockwise”, “counterclockwise”, “axial”, “radial”, “circumferential”, etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0093] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0094] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0095] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0096] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. 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 may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0097] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A dual power brake system, characterized in that: It includes a pressure reducing valve group and a service brake reversing valve group, the oil inlet of the pressure reducing valve group is connected to the pressure oil port of the brake pressure reducing valve for inputting pressure oil, the oil return port of the pressure reducing valve group is connected to the valve return oil port T for connecting to the oil tank, and the two-way oil port of the pressure reducing valve group is connected to the hydraulic trailer brake pilot oil port B, the two-way oil port of the pressure reducing valve group is also connected to the service brake reversing valve group, and the service brake reversing valve group is connected to the service brake control oil port; The pressure reducing valve group comprises a rear axle brake pressure reducing valve (2), the service brake reversing valve group comprises a left service brake reversing valve (1), the brake pressure reducing valve pressure oil port comprises a rear axle brake pressure reducing valve pressure oil port A1, and the service brake control oil port comprises a left service brake control oil port R2; the oil inlet 2a of the rear axle brake pressure reducing valve (2) is connected to the rear axle brake pressure reducing valve pressure oil port A1, the bidirectional oil port 2b of the rear axle brake pressure reducing valve (2) is simultaneously connected to the hydraulic trailer brake pilot oil port B and the oil port 1a of the left service brake reversing valve (1), the oil return port 2c of the rear axle brake pressure reducing valve (2) is connected to the valve oil return port T; the oil port 1c of the left service brake reversing valve (1) is connected to the left service brake control oil port R2; The pressure reducing valve group further comprises a front axle brake pressure reducing valve (3), the service brake reversing valve group further comprises a right service brake reversing valve (4), the brake pressure reducing valve pressure oil port comprises a front axle brake pressure reducing valve pressure oil port A2, and the service brake control oil port comprises a right service brake control oil port R1; the oil inlet 3a of the front axle brake pressure reducing valve (3) is connected to the front axle brake pressure reducing valve pressure oil port A2, the bidirectional oil port 3b of the front axle brake pressure reducing valve (3) is connected to the hydraulic trailer brake pilot oil port B, and the oil return port 3c of the front axle brake pressure reducing valve (3) is connected to the valve oil return port T; the oil port 4c of the right service brake reversing valve (4) is connected to the right service brake control oil port R1; and the bidirectional oil port 2b of the rear axle brake pressure reducing valve (2) is also connected to the oil port 4a of the right service brake reversing valve (4), and the oil port 4a of the right service brake reversing valve (4) is also connected to the hydraulic trailer brake pilot oil port B; It also comprises a solenoid valve (5), wherein the bidirectional oil port 2b of the rear axle brake pressure reducing valve (2) is connected to the oil port 5a of the solenoid valve (5), and the oil port 5b of the solenoid valve (5) is simultaneously connected to the oil port 1b of the left service brake reversing valve (1) and the oil port 4b of the right service brake reversing valve (4), and the oil port 5c of the solenoid valve (5) is connected to the valve oil return port T, and when the vehicle speed reaches a preset vehicle speed threshold, the solenoid valve (5) is used to control the bidirectional oil port 2b of the rear axle brake pressure reducing valve (2) to be simultaneously connected to the oil port 1b of the left service brake reversing valve (1) and the oil port 4b of the right service brake reversing valve (4); It also includes a hydraulically controlled reversing valve (6), wherein the oil port 6a of the hydraulically controlled reversing valve (6) is connected to the hydraulic trailer brake pilot oil port B, the oil port 6b of the hydraulically controlled reversing valve (6) is connected to the two-way oil port 3b of the front axle brake pressure reducing valve (3), and the hydraulically controlled reversing valve (6) controls the oil port 6a and the oil port 6b to be connected so that the two-way oil port 3b of the front axle brake pressure reducing valve (3) is connected to the hydraulic trailer brake pilot oil port B, and the oil port 6c of the hydraulically controlled reversing valve (6) is connected to the valve oil return port T; The oil port 1c of the left service brake reversing valve (1) and the oil port 4c of the right service brake reversing valve (4) are also connected to the hydraulically controlled reversing valve (6); It also comprises a shuttle valve (7), through which the oil port 6a of the hydraulically controlled reversing valve (6) and the two-way oil port 2b of the rear axle brake pressure reducing valve (2) are both connected to the hydraulic trailer brake pilot oil port B.

2. A dual power brake system according to claim 1, characterized in that: The shuttle valve (7) is also connected to the front axle service brake oil port F, the hydraulically controlled reversing valve (6) controls the oil port 6a and the oil port 6b to be connected, and the bidirectional oil port 3b of the front axle brake pressure reducing valve (3) is connected to the front axle service brake oil port F through the oil port 6a of the hydraulically controlled reversing valve (6).

3. A dual power brake system according to claim 1, characterized in that: The rear axle brake pressure reducing valve (2) and the front axle brake pressure reducing valve (3) are simultaneously connected to an intermediate connecting rod (8), and the left service brake reversing valve (1) and the right service brake reversing valve (4) are both provided with pedals, and the intermediate connecting rod (8) is arranged in linkage with the pedals.

4. An agricultural machinery and equipment, characterized in that: Comprising a dual power braking system as described in any one of claims 1-3.

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