Bulldozer shovel blade control system and bulldozer

Abstract

The invention discloses a bulldozer shovel blade control system and a bulldozer. The bulldozer shovel blade control system further comprises a hydraulic pump, a multi-way reversing valve and a control valve set. A working port of the multi-way reversing valve is connected with an oil inlet of the control valve group; a working port of the control valve group is respectively connected with a rod cavity and a rodless cavity of the left inclined oil cylinder and a rod cavity and a rodless cavity of the right inclined oil cylinder; wherein the control valve group has a double-cylinder tilting mode and a pitching angle adjusting mode, and when the control valve group is in the double-cylinder tilting mode, the control valve group controls a rod cavity of the left tilting oil cylinder to be connected with a rodless cavity of the right tilting oil cylinder and controls the rodless cavity of the left tilting oil cylinder to be connected with a rod cavity of the right tilting oil cylinder, so that the left tilting oil cylinder and the right tilting oil cylinder act reversely; and in a pitching angle adjusting mode, the control valve group controls the corresponding cavities of the left and right inclined oil cylinders to be connected, so that the left and right inclined oil cylinders act in the same direction. The problems that in the prior art, a hydraulic system is complex in design, the coupling degree of a control system is high, and the reliability of the system is affected are solved.

Description

Technical Field

[0001] This application relates to the field of bulldozer blade control technology, and in particular to a bulldozer blade control system and a bulldozer. Background Technology

[0002] The blade of a bulldozer needs to tilt left and right and pitch forward and backward. In existing technology, a multi-way directional valve is typically used to control the tilt cylinder's movement. Specifically, the multi-way directional valve connects to both the rod-side and rodless sides of the tilt cylinder. By operating the multi-way directional valve, hydraulic oil is supplied to either the rod-side or rodless side, thereby driving the tilt cylinder to extend or retract, thus adjusting the blade's posture.

[0003] However, in the existing technology, the left and right tilt and forward and backward pitch of the blade are all controlled by a multi-way directional valve, which makes the hydraulic system design complex, the control system highly coupled, and affects the reliability of the system. Summary of the Invention

[0004] The purpose of this application is to provide a bulldozer blade control system and a bulldozer, so as to solve the problem that in the prior art, the left and right tilt and forward and backward pitch of the blade are all controlled by a multi-way directional valve, which makes the hydraulic system design complex, the control system highly coupled, and affects the reliability of the system.

[0005] To solve the above-mentioned technical problems, this application adopts the following technical solution:

[0006] In a first aspect, this application provides a bulldozer blade control system, including a left tilt cylinder and a right tilt cylinder, and the control system includes a hydraulic pump, a multi-way directional valve and a control valve group.

[0007] The outlet of the hydraulic pump is connected to the inlet of the multi-way directional valve, the working port of the multi-way directional valve is connected to the inlet of the control valve group, and the working port of the control valve group is connected to the rod chamber and rodless chamber of the left tilting cylinder and the rod chamber and rodless chamber of the right tilting cylinder, respectively.

[0008] The control valve assembly has a dual-cylinder tilt mode and a pitch adjustment mode. In the dual-cylinder tilt mode, the control valve assembly controls the rod chamber of the left tilt cylinder and the rodless chamber of the right tilt cylinder to connect, and the rodless chamber of the left tilt cylinder and the rod chamber of the right tilt cylinder to connect, so that the left tilt cylinder and the right tilt cylinder move in opposite directions. In the pitch adjustment mode, the control valve assembly controls the rod chamber of the left tilt cylinder and the rod chamber of the right tilt cylinder to connect, and the rodless chamber of the left tilt cylinder and the rodless chamber of the right tilt cylinder to connect, so that the left tilt cylinder and the right tilt cylinder move in the same direction.

[0009] Compared with existing technologies, the technical effects achieved by this solution are as follows: by controlling the connection between the rod-side and rodless chambers of the left tilting cylinder and the rod-side and rodless chambers of the right tilting cylinder through the control valve group, the left and right tilting and forward and backward pitching of the blade are controlled, thereby reducing the complexity of the system and improving its reliability. Specifically, the control system includes a hydraulic pump, a multi-way directional valve, and a control valve assembly. The hydraulic pump is connected to the multi-way directional valve to supply hydraulic oil. The working port of the multi-way directional valve is connected to the oil inlet of the control valve assembly to supply oil to the control valve assembly. The control valve assembly has a dual-cylinder tilt mode and a pitch adjustment mode. In the dual-cylinder tilt mode, the control valve assembly controls the connection between the rod chamber of the left tilt cylinder and the rodless chamber of the right tilt cylinder, and the rodless chamber of the left tilt cylinder and the rod chamber of the right tilt cylinder are connected. When the blade needs to tilt to the left, the control valve assembly supplies hydraulic oil to the rod chamber of the left tilt cylinder and the rodless chamber of the right tilt cylinder, causing the left tilt cylinder to retract and the right tilt cylinder to extend, thereby tilting the blade to the left. When the blade needs to tilt to the right, the control valve assembly supplies hydraulic oil to the rodless chamber of the left tilt cylinder and the rod chamber of the right tilt cylinder, causing the left tilt cylinder to extend and the right tilt cylinder to retract, thereby tilting the blade to the right. When in pitch adjustment mode, the control valve group controls the connection of the corresponding chambers of the left and right tilt cylinders. When the blade needs to tilt forward, the control valve group supplies hydraulic oil to the rodless chambers of the left and right tilt cylinders. The left and right tilt cylinders extend synchronously, pushing the blade forward and increasing the pitch angle. When the blade needs to tilt backward, the control valve group supplies hydraulic oil to the rod chambers of the left and right tilt cylinders. The left and right tilt cylinders retract synchronously, pulling the blade backward and increasing the pitch angle.

[0010] Furthermore, the control valve assembly includes a second directional valve and a third directional valve; the working port a1 of the second directional valve is connected to the rodless chamber of the left tilting cylinder, the working port a2 of the second directional valve is connected to the rod chamber of the left tilting cylinder, the working port a3 of the second directional valve is connected to the working port b1 of the third directional valve, and the working port a4 of the second directional valve is connected to the working port b2 of the third directional valve; the working port b3 of the third directional valve is connected to the rod chamber of the right tilting cylinder, and the working port b4 of the third directional valve is connected to the rodless chamber of the right tilting cylinder; the working port A of the multi-way directional valve is connected between the rod chamber of the left tilting cylinder and the working port a2 of the second directional valve, and the working port B of the multi-way directional valve is connected between the rodless chamber of the left tilting cylinder and the working port a1 of the second directional valve.

[0011] Compared with existing technologies, the technical effects achieved by this technical solution are as follows: the connection between the rod-side and rodless-side chambers of the left and right tilting cylinders can be controlled by the second and third directional valves; the working ports A and B of the multi-way directional valve are directly connected between the left tilting cylinder and the second directional valve, enabling the multi-way directional valve to supply oil to both the left and right tilting cylinders simultaneously; at the same time, the second and third directional valves and the multi-way directional valve work together, with the second and third directional valves controlling the oil circuit and the multi-way directional valve controlling the oil supply, thereby controlling the movement of the blade.

[0012] Furthermore, when the control valve assembly is in the dual-cylinder tilting mode, the working port a1 of the second directional valve is connected to the working port a3, the working ports a2 and a4 of the second directional valve are connected, the working ports b1 and b3 of the third directional valve are connected, and the working ports b2 and b4 of the third directional valve are connected, so that the rod chamber of the left tilting cylinder and the rodless chamber of the right tilting cylinder are connected in parallel and connected to the working port A of the multi-way directional valve, and the rodless chamber of the left tilting cylinder and the rod chamber of the right tilting cylinder are connected in parallel and connected to the working port B of the multi-way directional valve.

[0013] Compared with existing technologies, the technical effects achieved by this technical solution are as follows: by connecting the rod-side and rodless chambers of the left tilting cylinder and the rodless and rod-side chambers of the right tilting cylinder in parallel and connecting them to a multi-way directional valve, the flow rate of hydraulic oil can synchronously flow into the left and right tilting cylinders when the multi-way directional valve supplies oil to the left and right tilting cylinders, thereby synchronizing the extension and retraction actions of the left and right tilting cylinders and improving the stability of the system.

[0014] Furthermore, the control valve assembly also includes: a flow divider / combiner valve, the inlet of which is connected to the working port B of the multi-way directional valve; the first outlet of which is connected between the rodless chamber of the left tilting cylinder and the working port a1 of the second directional valve; and the second outlet of which is connected between the rodless chamber of the right tilting cylinder and the working port b4 of the third directional valve. When the control valve assembly is in the pitch adjustment mode, the working ports a2 and a3 of the second directional valve are connected, and the working ports b1 and b3 of the third directional valve are connected, so that the rod chambers of the left tilting cylinder and the right tilting cylinder are connected in parallel and connected to the working port A of the multi-way directional valve. The rodless chambers of the left tilting cylinder and the right tilting cylinder are connected in parallel through the flow divider / combiner valve and connected to the working port B of the multi-way directional valve.

[0015] Compared with existing technologies, the technical effects achieved by this solution are as follows: the flow divider / combiner valve can divert hydraulic oil supplied by the multi-way directional valve to the rodless chambers of the left and right tilting cylinders in a fixed ratio, and can also proportionally combine the hydraulic oil returning from the rodless chambers of the left and right tilting cylinders. The flow divider / combiner valve can proportionally control the inlet or outlet flow of the left and right tilting cylinders to ensure their synchronization.

[0016] Furthermore, the control valve assembly also includes: a first directional valve, the working port c1 of which is connected to the second outlet of the flow divider / combiner valve; the working port c2 of which is connected in parallel with the first outlet of the flow divider / combiner valve and then connected between the rodless chamber of the left tilting cylinder and the working port a1 of the second directional valve; and the working port c3 of which is connected between the rodless chamber of the right tilting cylinder and the working port b4 of the third directional valve. When the control valve assembly is in dual-cylinder tilt mode, the working ports c1 and c2 of the first directional valve are connected so that the working port B of the multi-way directional valve is connected between the rodless chamber of the left tilting cylinder and the working port a1 of the second directional valve. When the control valve assembly is in pitch adjustment mode, the working ports c1 and c3 of the first directional valve are connected so that the rodless chambers of the left and right tilting cylinders are connected in parallel and then connected to the working port B of the multi-way directional valve.

[0017] Compared with existing technologies, the technical effects achieved by this technical solution are as follows: The first directional valve is used to switch the connection object of the working port B of the multi-way directional valve. Specifically, when in the dual-cylinder tilt mode, the hydraulic oil flowing out from the second outlet of the diverter valve passes through the working ports c1 and c2 of the first directional valve and is connected in parallel with the first outlet of the diverter valve, so that all the hydraulic oil is delivered to the rodless chamber of the left tilt cylinder and the working port a1 of the second directional valve; when in the pitch adjustment mode, the hydraulic oil flowing out from the second outlet of the diverter valve passes through the working ports c1 and c3 of the first directional valve and is delivered to the rodless chamber of the right tilt cylinder.

[0018] Furthermore, the control valve assembly also has a single-cylinder tilt mode; when the control valve assembly is in the single-cylinder tilt mode, the working port b1 of the third directional valve is disconnected from the working port b3, and the working port b2 of the third directional valve is disconnected from the working port b4, so that the rod chamber of the left tilt cylinder is connected to the working port A of the multi-way directional valve, and the rodless chamber of the left tilt cylinder is connected to the working port B of the multi-way directional valve.

[0019] Furthermore, the control valve assembly includes a first control valve, a second control valve, and a third control valve; the outlet of the first control valve is connected to the control port of the second directional valve, the outlet of the second control valve is connected to the control port of the third directional valve, and the outlet of the third directional valve is connected to the control port of the first directional valve.

[0020] Furthermore, it also includes a pilot control valve assembly and a pilot pump; the oil outlet of the pilot pump is connected to the oil inlet of the pilot control valve assembly, and the oil outlet of the pilot control valve assembly is connected to the inlet of the first control valve, the inlet of the second control valve, and the inlet of the third control valve, respectively.

[0021] Secondly, this application also provides a bulldozer, which includes a bulldozer blade control system as described in any of the foregoing claims.

[0022] Furthermore, the bulldozer includes: a blade; a left push rod and a right push rod, the left push rod being connected to the blade via a second pivot, and the right push rod being connected to the blade via a first pivot; a left tilting cylinder and a right tilting cylinder, the piston rod end of the left tilting cylinder being connected to the blade, and its cylinder end being connected to the left push rod; the piston rod end of the right tilting cylinder being connected to the blade, and its cylinder end being connected to the right push rod.

[0023] Compared with the prior art, the beneficial effects achieved by this application are as follows:

[0024] 1. By controlling the connection between the rod-side and rodless chambers of the left tilting cylinder and the rod-side and rodless chambers of the right tilting cylinder through the control valve group, the left and right tilting and forward and backward pitching of the blade are controlled, which reduces the complexity of the system and improves the reliability of the system.

[0025] 2. The flow divider valve can be used to control the oil inlet or outlet of the left and right tilting cylinders in a certain proportion to ensure the synchronization of the left and right tilting cylinders. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in the embodiments of this disclosure or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this disclosure. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0027] Figure 1 This is a system diagram of an embodiment of a bulldozer blade control system provided in this application.

[0028] Figure 2 This is a structural diagram of the bulldozer blade provided in this application.

[0029] Figure 3 This is a system diagram of the electrical control system provided in this application.

[0030] Explanation of reference numerals in the attached figures:

[0031] 1. Blade; 2. Right push rod; 3. Frame; 4. Connecting rod; 5. Left push rod; 6. First pivot; 7. Second pivot; 8. Right tilt cylinder; 9. Left tilt cylinder; 10. Control valve assembly; 11. Third pivot; 12. Fourth pivot; 13. Fifth pivot; 14. Sixth pivot;

[0032] 15. Return oil filter; 16. Suction oil filter; 17. Hydraulic pump; 18. Multi-way directional valve; 19. Pilot control valve assembly; 20. Pilot pump; 21. Hydraulic oil tank; 22. Divider / combiner valve; 23. First directional valve; 24. First control valve; 25. Second directional valve; 26. Third directional valve; 27. Second control valve; 28. Third control valve;

[0033] 29. CAN switch panel; 30. Operating handle; 31. LCD display; 32. Controller; 33. Switch button; 34. Single cylinder tilt mode button; 35. Pitch angle adjustment mode button; 36. Self-reset toggle. Detailed Implementation

[0034] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit this application or its application or use.

[0035] Example 1:

[0036] This embodiment provides a bulldozer blade control system, which controls the left tilt cylinder 9 and the right tilt cylinder 8, such as... Figure 1 As shown, the control system includes a hydraulic oil tank 21, a hydraulic pump 17, a multi-way directional valve 18, and a control valve group 10.

[0037] Specifically, the hydraulic pump 17 is a piston pump. The oil inlet of the hydraulic pump 17 is connected to the hydraulic oil tank 21, and the oil outlet of the hydraulic pump 17 is connected to the oil inlet of the multi-way directional valve 18. The working port A of the multi-way directional valve 18 is connected to the oil inlet A of the control valve group 10, the working port B of the multi-way directional valve 18 is connected to the oil inlet B of the control valve group 10, and the control port LS of the multi-way directional valve 18 is connected to the control port LS of the hydraulic pump 17. The working port A1 of the control valve group 10 is connected to the rodless chamber of the left tilting cylinder 9, the working port B1 of the control valve group 10 is connected to the rod chamber of the left tilting cylinder 9, the working port A2 of the control valve group 10 is connected to the rodless chamber of the right tilting cylinder 8, and the working port B2 of the control valve group 10 is connected to the rod chamber of the left tilting cylinder 9.

[0038] The control valve assembly 10 has a dual-cylinder tilt mode and a pitch adjustment mode: When in dual-cylinder tilt mode, the control valve assembly 10 controls the rod chamber of the left tilt cylinder 9 and the rodless chamber of the right tilt cylinder 8 to connect, and the rodless chamber of the left tilt cylinder 9 and the rod chamber of the right tilt cylinder 8 to connect, so that the left tilt cylinder 9 and the right tilt cylinder 8 move in opposite directions; when in pitch adjustment mode, the control valve assembly 10 controls the rod chamber of the left tilt cylinder 9 and the rod chamber of the right tilt cylinder 8 to connect, and the rodless chamber of the left tilt cylinder 9 and the rodless chamber of the right tilt cylinder 8 to connect, so that the left tilt cylinder 9 and the right tilt cylinder 8 move in the same direction.

[0039] Furthermore, the control valve assembly 10 includes a second directional valve 25 and a third directional valve 26. The working port a1 of the second directional valve 25 is connected to the rodless chamber of the left tilting cylinder 9 through the working port A1 of the control valve assembly 10. The working port a2 of the second directional valve 25 is connected to the rod chamber of the left tilting cylinder 9 through the working port B1 of the control valve assembly 10. The working port a3 of the second directional valve 25 is connected to the working port b1 of the third directional valve 26. The working port a4 of the second directional valve 25 is connected to the working port b2 of the third directional valve 26. The working port b3 of the third directional valve 26 is connected to the rod chamber of the right tilting cylinder 8 through the working port B2 of the control valve assembly 10. The working port b4 of the third directional valve 26 is connected to the rodless chamber of the right tilting cylinder 8 through the working port A2 of the control valve assembly 10. The working port A of the multi-way directional valve 18 is connected to the oil inlet A of the control valve assembly 10. The working port B of the multi-way directional valve 18 is connected to the oil inlet B of the control valve assembly 10.

[0040] Furthermore, the control valve assembly 10 also includes a flow divider / combiner valve 22 and a first directional valve 23. The inlet of the flow divider / combiner valve 22 is connected to the oil inlet B of the control valve assembly 10. The first outlet of the flow divider / combiner valve 22 is connected between the working port A1 of the control valve assembly 10 and the working port a1 of the second directional valve 25. The second outlet of the flow divider / combiner valve 22 is connected to the working port c1 of the first directional valve 23. The working port c2 of the first directional valve 23 is connected in parallel with the first outlet of the flow divider / combiner valve 22 and is connected between the working port A1 of the control valve assembly 10 and the working port a1 of the second directional valve 25. The working port c3 of the first directional valve 23 is connected between the working port A2 of the control valve assembly 10 and the working port b4 of the third directional valve 26.

[0041] Specifically, the flow divider / combiner valve 22 can be configured to divide the inlet flow rate to make the output flow rate of the first outlet and the second outlet 1:1; it can also be configured to combine the flow rates of the first outlet and the second outlet to make the input flow rate of the first outlet and the second outlet 1:1. The flow divider / combiner valve 22 can make the oil inlet or outlet flow rate of the left and right tilting cylinders the same, so as to ensure the synchronicity of the left and right tilting cylinder actions.

[0042] Specifically, the first directional valve 23, the second directional valve 25, and the third directional valve 26 are hydraulically controlled directional valves. The spring ports of the first directional valve 23, the second directional valve 25, and the third directional valve 26 are respectively connected to the T port of the control valve assembly 10, and the T port of the control valve assembly 10 is connected to the hydraulic oil tank 21.

[0043] Specifically, the normal position of the first directional valve 23 is that working ports c1 and c2 are connected; the normal position of the second directional valve 25 is that working ports a1 and a3 are connected, and working ports a2 and a4 are connected; the normal position of the third directional valve 26 is that working ports b1, b2, b3, and b4 are all disconnected.

[0044] Further, the control valve assembly 10 includes a first control valve 24, a second control valve 27, and a third control valve 28. The first control valve 24, the second control valve 27, and the third control valve 28 are electrically controlled directional valves. Port 1 of the first control valve 24 and the third control valve 28 is connected to the X port of the control valve assembly 10, port 2 of the first control valve 24 and the third control valve 28 is connected to the T port of the control valve assembly 10, port 3 of the first control valve 24 is connected to the control port of the second directional valve 25, and port 3 of the third control valve 28 is connected to the control port of the first directional valve 23. Port 1 of the second control valve 27 is connected to the T port of the control valve assembly 10, port 2 of the second control valve 27 is connected to the X port of the control valve assembly 10, and port 3 of the second control valve 27 is connected to the control port of the third directional valve 26. Ports 3 of the first control valve 24, the second control valve 27, and the third control valve 28 are all outlets.

[0045] Specifically, the normal position of the first control valve 24 is that ports 2 and 3 are connected, the normal position of the second control valve 27 is that ports 2 and 3 are connected, and the normal position of the third control valve 28 is that ports 2 and 3 are connected.

[0046] Furthermore, the blade control system also includes a pilot control valve assembly 19 and a pilot pump 20; the oil outlet of the pilot pump 20 is connected to the oil inlet of the pilot control valve assembly 19, and the oil outlet of the pilot control valve assembly 19 is connected to the X port of the control valve assembly 10.

[0047] Furthermore, such as Figure 3 As shown, this embodiment also includes an electrical control system, which is used to control the blade control system. The electrical control system includes a CAN switch panel 29, an operating handle, an LCD display, and a controller. The CAN switch panel 29 includes a switch button, a single-cylinder tilt mode button, and a pitch angle adjustment mode button. The controller receives the output signals from the CAN switch panel 29 and the operating handle, and sends corresponding control signals to the multi-way directional valve 18, the pilot control valve group 19, and the control valve group 10 to control the blade control system.

[0048] Specifically, the working principle of the bulldozer blade control system in this embodiment of the invention is as follows:

[0049] Dual-cylinder tilt mode: Pressing the switch button 33 on the CAN switch panel 29 starts the blade control system. After receiving the input signal, the controller 32 outputs the corresponding signal to the pilot control valve group 19. The valve core of the pilot control valve group 19 reverses, and the hydraulic oil output by the pilot pump 20 flows through the pilot control valve group 19, the X port of the control valve group 10, the 2 and 3 ports of the second control valve 27, and enters the control port of the third directional valve 26, pushing the third directional valve 26 to perform a reversing action. The working ports b1 and b3 of the third directional valve 26 are connected, and the working ports b2 and b4 are connected. At this time, the rod chamber of the left tilt cylinder 9 is connected to the rodless chamber of the right tilt cylinder 8, and the rodless chamber of the left tilt cylinder 9 is connected to the rod chamber of the right tilt cylinder 8. The LCD display 31 shows that it is in dual-cylinder tilt mode. If the operating handle 30 is swung to the left at this time, the controller 32 receives the input signal and outputs the corresponding signal to the multi-way directional valve 18. The valve core of the multi-way directional valve 18 is reversed, and the hydraulic oil output by the hydraulic pump 17 flows through the oil inlet and working port A of the multi-way directional valve 18, the oil inlet A of the control valve group 10, the working port B1 and working port A2 of the control valve group 10, and enters the rod chamber of the left tilting cylinder 9 and the rodless chamber of the right tilting cylinder 8. The piston rod of the left tilting cylinder 9 retracts, and the piston rod of the right tilting cylinder 8 extends. When the blade 1 is subjected to the right-side thrust and the left-side pull, the blade 1 tilts to the left. If the operating handle 30 is swung to the right at this time, the controller 32 receives the input signal and outputs the corresponding signal to the multi-way directional valve 18. The valve core of the multi-way directional valve 18 is reversed, and the hydraulic oil output by the hydraulic pump 17 flows through the oil inlet and working port B of the multi-way directional valve 18, the oil inlet B of the control valve group 10, the working port A1 and working port B2 of the control valve group 10, and enters the rodless chamber of the left tilting cylinder 9 and the rod chamber of the right tilting cylinder 8. The piston rod of the left tilting cylinder 9 extends, and the piston rod of the right tilting cylinder 8 retracts. When the blade 1 is subjected to the left-side thrust and the right-side pull, the blade 1 tilts to the right.

[0050] Pitch Adjustment Mode: Press the switch button 33 and the pitch adjustment mode button 35 on the CAN switch panel 29. After receiving the input signal, the controller 32 outputs the corresponding signal to the pilot control valve group 19, the control valve group 10, and the LCD display 31. The valve cores of the pilot control valve group 19, the first control valve 24, and the third control valve 28 reverse. The hydraulic oil output by the pilot pump 20 flows through the pilot control valve group 19 and enters the X port of the control valve group 10, where it is divided into three paths. The first path of hydraulic oil passes through ports 2 and 3 of the second control valve 27 and enters the control port of the third directional valve 26, pushing the third directional valve 26 to perform a reversing action, causing the third... Working ports b1 and b3 of directional valve 26 are connected, and working ports b2 and b4 are connected. Second hydraulic oil flows through working ports c1 and c3 of the first control valve 24 to the control port of the second directional valve 25, pushing the second directional valve 25 to perform a reversing action, connecting working ports a2 and a3 and disconnecting working ports a1 and a4. Third hydraulic oil flows through working ports c1 and c3 of the third control valve 28 to the control port of the first directional valve 23, pushing the first directional valve 23 to perform a reversing action, connecting working ports c1 and c3. At this time, the rod chamber of the left tilt cylinder 9 is connected to the rod chamber of the right tilt cylinder 8, the rodless chamber of the left tilt cylinder 9 is connected to the first outlet of the flow divider / combiner valve 22, and the rodless chamber of the right tilt cylinder 8 is connected to the second outlet of the flow divider / combiner valve 22. The LCD display 31 shows that it is in pitch adjustment mode.If the self-reset switch 36 on the operating handle 30 is moved forward at this time, the controller 32 receives the input signal and outputs the corresponding signal to the multi-way directional valve 18. The valve core of the multi-way directional valve 18 reverses, and the hydraulic oil output by the hydraulic pump 17 flows through the inlet and working port B of the multi-way directional valve 18, the inlet B of the control valve group 10, and enters the inlet of the diverter valve 22. The diverter valve 22 evenly distributes the flow to the first outlet and the second outlet. Half of the hydraulic oil flows through the working port A1 of the control valve group 10 into the rodless chamber of the left tilting cylinder 9. Half of the hydraulic oil flows through the working port c1 and working port c3 of the first directional valve 23, the working port A2 of the control valve group 10, and enters the rodless chamber of the right tilting cylinder 8. The piston rods of the left and right tilting cylinders extend synchronously, and the blade 1 is pushed by the left and right sides. The blade 1 tilts forward, and the tilt angle increases. If the self-reset switch 36 on the operating handle 30 is moved backward, the controller 32 receives the input signal and outputs the corresponding signal to the multi-way directional valve 18. The ... After receiving the input signal, the controller 32 outputs a corresponding signal to the multi-way directional valve 18. The valve core of the multi-way directional valve 18 reverses, and the hydraulic oil output by the hydraulic pump 17 flows through the inlet and working port A of the multi-way directional valve, the inlet A of the control valve group 10, the B1 and working port B2 of the control valve group 10, and enters the rod chamber of the left and right tilting cylinders. The piston rods of the left and right tilting cylinders retract. The return oil from the rodless chamber of the left tilting cylinder 9 flows through the working port A1 of the control valve group 10 and enters the first outlet of the flow divider and combiner valve 22. The return oil from the rodless chamber of the right tilting cylinder 8 flows through the working port A2 of the control valve group 10, the working port c3 and working port c1 of the first directional valve 23, and enters the second outlet of the flow divider and combiner valve 22. The flow divider and combiner valve 22 evenly distributes the flow of the first outlet and the second outlet. The blade 1 is pulled by the left and right sides, and the blade 1 will tilt backward, increasing the elevation angle.

[0051] Single-cylinder tilt mode: Press the switch button 33 and the single-cylinder tilt mode button 34 on the CAN switch panel 29. After receiving the input signal, the controller 32 outputs the corresponding signal to the pilot control valve group 19, the control valve group 10, and the LCD display 31. The valve cores of the pilot control valve group 19 and the second control valve 27 switch directions. The hydraulic oil output by the pilot pump 20 passes through the pilot control valve group 19 and enters the X port of the control valve group 10 to wait. The working port a1 of the second control valve 27 is connected to the working port a3. The valve core of the third reversing valve moves to the normal position, and the working ports b1, b2, b3, and b4 are all disconnected. At this time, the rodless chamber and the rod chamber of the right tilt cylinder 8 are disconnected from the oil circuit, and the LCD display 31 shows that it is in single-cylinder tilt mode. If the operating handle 30 is swung to the left at this time, the controller 32 receives the input signal and outputs the corresponding signal to the multi-way directional valve 18. The valve core of the multi-way directional valve 18 is reversed, and the hydraulic oil output by the hydraulic pump 17 flows through the oil inlet and working port A of the multi-way directional valve 18, the oil inlet A of the control valve group 10, and the working port B1 of the control valve group 10, and enters the rod chamber of the left tilting cylinder 9. The piston rod of the left tilting cylinder 9 retracts, the piston rod of the right tilting cylinder 8 remains stationary, and the blade 1 is pulled by the left side, causing the blade 1 to tilt to the left. If the operating handle 30 is swung to the right, the controller 32 receives the input signal and outputs the corresponding signal to the multi-way directional valve 18. The valve core of the multi-way directional valve 18 is reversed, and the hydraulic oil output by the hydraulic pump 17 flows through the inlet and working port B of the multi-way directional valve, the inlet B of the control valve group 10, and the working port A1 of the control valve group 10, and enters the rodless chamber of the left tilting cylinder 9. The piston rod of the left tilting cylinder 9 extends, while the piston rod of the right tilting cylinder 8 remains stationary. The blade 1 is pushed by the left side, and the blade 1 tilts to the right.

[0052] Furthermore, the blade control system also includes a suction filter 16 and a return filter 15. The inlet of the suction filter 16 is connected to the hydraulic oil tank 21, and its outlet is connected to the inlet of the hydraulic pump 17. The inlet of the return filter 15 is connected to the return port T of the multi-way directional valve 18, and its outlet is connected to the hydraulic oil tank 21.

[0053] Specifically, in order to precisely control the left and right tilt angles and front and back pitch angles of the blade 1, in this embodiment, the multi-way directional valve 18 is an electro-proportional multi-way directional valve. The controller 32 outputs a proportional signal to the electromagnet of the multi-way directional valve 18 based on the input signal from the operating handle 30. The valve core of the multi-way directional valve 18 exhibits different opening degrees, adjusting the oil flow rate entering the left and right tilt cylinders. More specifically, the greater the amplitude of the operating handle 30's movement, the greater the current output by the controller 32, the greater the opening degree of the multi-way directional valve 18, the greater the oil flow rate entering the left and right tilt cylinders, and the faster the left and right tilt cylinders move, and vice versa.

[0054] Specifically, to prevent misoperation, when the switch button 33 is not activated, the controller 32 will not output a control signal if the operating handle 30 is swung or the self-reset switch 36 on the operating handle 30 is toggled.

[0055] Example 2:

[0056] This embodiment provides a bulldozer, which includes a control system for the bulldozer blade 1 as shown in Embodiment 1.

[0057] like Figure 2 As shown, the bulldozer further includes a blade 1, a left push rod 5, a right push rod 2, a frame 3, a connecting rod 4, a first rotating shaft 6, a second rotating shaft 7, a third rotating shaft 11, a fourth rotating shaft 12, a fifth rotating shaft 13 and a sixth rotating shaft 14, as well as a left tilting cylinder 9 and a right tilting cylinder 8 as in Embodiment 1.

[0058] Specifically, the blade 1 is rotatably connected to the right push rod 2 and the left push rod 5 via the first rotating shaft 6 and the second rotating shaft 7, respectively. The two ends of the connecting rod 4 are connected to the blade 1 and the frame 3, respectively. The piston rod end of the right tilting cylinder 8 is rotatably connected to the blade 1 via the third rotating shaft 11. The cylinder end of the right tilting cylinder 8 is rotatably connected to the right push rod 2 via the fourth rotating shaft 12. The piston rod end of the left tilting cylinder 9 is rotatably connected to the blade 1 via the fifth rotating shaft 13. The cylinder end of the left tilting cylinder 9 is rotatably connected to the right push rod 2 via the sixth rotating shaft 14. The control valve group 10 is installed on the blade 1.

[0059] Furthermore, the terms "first," "second," etc., 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 defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "a plurality of" means two or more.

[0060] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; and they can refer to connections within two components. Those skilled in the art will understand the specific meaning of the above terms in this application based on the specific circumstances.

[0061] The above description is only a preferred embodiment of this application. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of this application, and these improvements and modifications should also be considered within the scope of protection of this application.

Claims

1. A bulldozer blade control system, comprising a left tilt cylinder (9) and a right tilt cylinder (8), characterized in that, It also includes a hydraulic pump (17), a multi-way directional valve (18), and a control valve assembly (10). The outlet of the hydraulic pump (17) is connected to the inlet of the multi-way directional valve (18), the working port of the multi-way directional valve (18) is connected to the inlet of the control valve group (10), and the working port of the control valve group (10) is connected to the rod chamber and rodless chamber of the left tilting cylinder (9) and the rod chamber and rodless chamber of the right tilting cylinder (8), respectively. The control valve group (10) has a dual-cylinder tilt mode and a pitch adjustment mode. When in the dual-cylinder tilt mode, the control valve group (10) controls the rod chamber of the left tilt cylinder (9) and the rodless chamber of the right tilt cylinder (8) to connect, and the rodless chamber of the left tilt cylinder (9) and the rod chamber of the right tilt cylinder (8) to connect, so that the left tilt cylinder (9) and the right tilt cylinder (8) move in opposite directions. When in the pitch adjustment mode, the control valve group (10) controls the rod chamber of the left tilt cylinder (9) and the rod chamber of the right tilt cylinder (8) to connect, and the rodless chamber of the left tilt cylinder (9) and the rodless chamber of the right tilt cylinder (8) to connect, so that the left tilt cylinder (9) and the right tilt cylinder (8) move in the same direction.

2. The bulldozer blade control system according to claim 1, characterized in that, The control valve group (10) includes a second directional valve (25) and a third directional valve (26). The working port a1 of the second reversing valve (25) is connected to the rodless chamber of the left tilting cylinder (9), the working port a2 of the second reversing valve (25) is connected to the rod chamber of the left tilting cylinder (9), the working port a3 of the second reversing valve (25) is connected to the working port b1 of the third reversing valve (26), and the working port a4 of the second reversing valve (25) is connected to the working port b2 of the third reversing valve (26). The working port b3 of the third directional valve (26) is connected to the rod chamber of the right tilting cylinder (8), and the working port b4 of the third directional valve (26) is connected to the rodless chamber of the right tilting cylinder (8). The working port A of the multi-way directional valve (18) is connected between the rod chamber of the left tilting cylinder (9) and the working port a2 of the second directional valve (25), and the working port B of the multi-way directional valve (18) is connected between the rodless chamber of the left tilting cylinder (9) and the working port a1 of the second directional valve (25).

3. The bulldozer blade control system according to claim 2, characterized in that, When the control valve group (10) is in the dual-cylinder tilt mode, the working port a1 of the second reversing valve (25) is connected to the working port a3, the working port a2 of the second reversing valve (25) is connected to the working port a4, the working port b1 of the third reversing valve (26) is connected to the working port b3, and the working port b2 of the third reversing valve (26) is connected to the working port b4, so that the rod chamber of the left tilting cylinder (9) and the rodless chamber of the right tilting cylinder (8) are connected in parallel and connected to the working port A of the multi-way reversing valve (18), and the rodless chamber of the left tilting cylinder (9) and the rod chamber of the right tilting cylinder (8) are connected in parallel and connected to the working port B of the multi-way reversing valve (18).

4. The bulldozer blade control system according to claim 2, characterized in that, The control valve assembly (10) also includes: The flow divider and combiner valve (22) has its inlet connected to the working port B of the multi-way directional valve (18), and its first outlet connected between the rodless chamber of the left tilting cylinder (9) and the working port a1 of the second directional valve (25). The first outlet of the flow divider and combiner valve (22) is connected between the rodless chamber of the right tilting cylinder (8) and the working port b4 of the third directional valve (26). When the control valve group (10) is in the pitch adjustment mode, the working port a2 of the second reversing valve (25) is connected to the working port a3, and the working port b1 of the third reversing valve (26) is connected to the working port b3, so that the rod chamber of the left tilting cylinder (9) and the rod chamber of the right tilting cylinder (8) are connected in parallel and connected to the working port A of the multi-way reversing valve (18). The rodless chamber of the left tilting cylinder (9) and the rodless chamber of the right tilting cylinder (8) are connected in parallel through the flow divider and combiner valve (22) and connected to the working port B of the multi-way reversing valve (18).

5. The bulldozer blade control system according to claim 4, characterized in that, The control valve assembly (10) also includes: The first reversing valve (23) has its working port c1 connected to the second outlet of the diverter valve (22). The working port c2 of the first reversing valve (23) is connected in parallel with the first outlet of the diverter valve (22) and then connected between the rodless chamber of the left tilting cylinder (9) and the working port a1 of the second reversing valve (25). The working port c3 of the first reversing valve (23) is connected between the rodless chamber of the right tilting cylinder (8) and the working port b4 of the third reversing valve (26). When the control valve group (10) is in the dual-cylinder tilt mode, the working port c1 of the first reversing valve (23) is connected to the working port c2, so that the working port B of the multi-way reversing valve (18) is connected between the rodless chamber of the left tilting cylinder (9) and the working port a1 of the second reversing valve (25); when the control valve group (10) is in the pitch adjustment mode, the working port c1 of the first reversing valve (23) is connected to the working port c3, so that the rodless chamber of the left tilting cylinder (9) and the rodless chamber of the right tilting cylinder (8) are connected in parallel and connected to the working port B of the multi-way reversing valve (18).

6. The bulldozer blade control system according to claim 2, characterized in that, The control valve assembly (10) also has a single-cylinder tilt mode; When the control valve group (10) is in single-cylinder tilt mode, the working port b1 of the third directional valve (26) is disconnected from the working port b3, and the working port b2 of the third directional valve (26) is disconnected from the working port b4, so that the rod chamber of the left tilt cylinder (9) is connected to the working port A of the multi-way directional valve (18), and the rodless chamber of the left tilt cylinder (9) is connected to the working port B of the multi-way directional valve (18).

7. The bulldozer blade control system according to claim 5, characterized in that, The control valve group (10) also includes a first control valve (24), a second control valve (27) and a third control valve (28). The outlet of the first control valve (24) is connected to the control port of the second reversing valve (25), the outlet of the second control valve (27) is connected to the control port of the third reversing valve (26), and the outlet of the third reversing valve (26) is connected to the control port of the first reversing valve (23).

8. The bulldozer blade control system according to claim 7, characterized in that, It also includes a pilot control valve assembly (19) and a pilot pump (20); The oil outlet of the pilot pump (20) is connected to the oil inlet of the pilot control valve group (19), and the oil outlet of the pilot control valve group (19) is connected to the inlet of the first control valve (24), the inlet of the second control valve (27), and the inlet of the third control valve (28), respectively.

9. A bulldozer, characterized in that, The bulldozer includes a bulldozer blade control system as described in any one of claims 1 to 8.

10. The bulldozer according to claim 9, characterized in that, include: Shovel (1); Left push rod (5) and right push rod (2), the left push rod (5) is connected to the blade through the second pivot (7), and the right push rod (2) is connected to the blade through the first pivot (6); The piston rod end of the left tilting cylinder (9) is connected to the shovel (1), and its cylinder end is connected to the left push rod (5); the piston rod end of the right tilting cylinder (8) is connected to the shovel (1), and its cylinder end is connected to the right push rod (2).

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