Upper-vehicle leveling control system of excavator and excavator

Abstract

The utility model discloses an excavator upper vehicle leveling control system and an excavator, and the excavator upper vehicle leveling control system comprises a leveling oil cylinder of which one end is hinged with an excavator upper vehicle and the other end is hinged with an excavator lower vehicle, the leveling oil cylinder comprises a front leveling oil cylinder arranged at the front part of the excavator and a rear leveling oil cylinder arranged at the rear part of the excavator; the leveling valve group is respectively connected with the front leveling oil cylinder and the rear leveling oil cylinder, a working port I of the leveling valve group is connected with a large cavity of the front leveling oil cylinder, a working port II of the leveling valve group is connected with a small cavity of the front leveling oil cylinder, a working port III of the leveling valve group is connected with a large cavity of the rear leveling oil cylinder, and a working port IV of the leveling valve group is connected with the small cavity of the rear leveling oil cylinder; and two-way hydraulic control one-way valves are arranged on the hydraulic pipeline between the leveling valve group and the front leveling oil cylinder and the hydraulic pipeline between the leveling valve group and the rear leveling oil cylinder. The pressure of the leveling oil cylinder can be kept stable for a long time, so that the leveling stability of an excavator truck is ensured.

Description

Technical Field

[0001] This utility model belongs to the field of excavator technology, specifically relating to an excavator upper leveling control system and an excavator. Background Technology

[0002] Tracked excavators typically operate in complex conditions, often on uneven ground, and sometimes even on slopes with an angle (usually less than 35°). When the bucket is full of material, turning from the bottom of the slope to the top can be difficult or impossible due to the force of gravity. When turning from the top of the slope to the bottom, the excavator may suddenly stop due to greater inertia than when working on flat ground, making it difficult to stop quickly. This can cause the excavator to become unstable and overturn, creating a dangerous situation.

[0003] In many current applications, when the ground has a slope (usually greater than 10°), the common practice is to reduce the climbing angle by having the excavator level the slope in a zigzag pattern to create a road for climbing. At the turns, a turning platform is excavated and leveled, and a working platform is also excavated and leveled at the work site to ensure the excavator is basically level before commencing work. This approach requires the excavator to level the slope, which generates additional workload and is time-consuming and labor-intensive.

[0004] Currently known excavator leveling schemes include a leveling mechanism that uses a hinge point support at one end and a hydraulic cylinder direct support at the other end to achieve levelness of the excavator's upper body. For example... Figure 1 As shown, this design is simple in structure and stable in operation; however, because it uses a single-end cylinder for direct support, under heavy working loads, internal leakage in the cylinder and hydraulic system makes it impossible to maintain the excavator's upper structure in a stable leveling state for extended periods. Therefore, improvements to the hydraulic system are needed. Utility Model Content

[0005] To address the shortcomings of existing technologies, this utility model provides a leveling control system for an excavator upper structure and an excavator, which can maintain stable pressure of the leveling cylinder for extended periods, thereby ensuring the leveling stability of the excavator upper structure.

[0006] To achieve the above objectives, the technical solution adopted by this utility model is as follows:

[0007] In a first aspect, a leveling control system for an excavator upper carriage is provided, comprising: a leveling cylinder with one end hinged to the excavator upper carriage and the other end hinged to the excavator lower carriage, the leveling cylinder including a front leveling cylinder disposed at the front of the excavator and a rear leveling cylinder disposed at the rear of the excavator; a leveling valve assembly connected to the front leveling cylinder and the rear leveling cylinder respectively, wherein the working port one of the leveling valve assembly is connected to the large chamber of the front leveling cylinder, the working port two is connected to the small chamber of the front leveling cylinder, the working port three is connected to the large chamber of the rear leveling cylinder, and the working port four is connected to the small chamber of the rear leveling cylinder; and a bidirectional hydraulically controlled check valve is installed on the hydraulic lines between the leveling valve assembly and the front leveling cylinder and on the hydraulic lines between the leveling valve assembly and the rear leveling cylinder.

[0008] Furthermore, it also includes a pressure sensor 1 for detecting the pressure in the large chamber of the front leveling cylinder and a pressure sensor 2 for detecting the pressure in the large chamber of the rear leveling cylinder.

[0009] Furthermore, it also includes tilt sensor 1 for detecting the angle between the excavator's upper carriage and the horizontal plane, and tilt sensor 2 for detecting the angle between the excavator's lower carriage and the horizontal plane.

[0010] Furthermore, the leveling valve assembly includes: a switching valve, the inlet of which is connected to the inlet of the leveling valve assembly, and the outlet of which is connected to the inlet of directional valve one and the inlet of directional valve two, respectively; the outlet one of directional valve one is connected to the working port one of the leveling valve assembly through throttle valve one, the outlet two of directional valve one is connected to the working port two of the leveling valve assembly through throttle valve two, the outlet one of directional valve two is connected to the working port four of the leveling valve assembly through throttle valve three, and the outlet two of directional valve two is connected to the working port three of the leveling valve assembly through throttle valve four.

[0011] Furthermore, the leveling valve assembly also includes: overflow valve one and overflow valve two, overflow valve one being connected in parallel with throttle valve one, and overflow valve two being connected in parallel with throttle valve four.

[0012] Furthermore, when the switch valve is in the connected position, directional valve one is in the left position, and directional valve two is in the left position, hydraulic oil enters the small chamber of the front leveling cylinder through the switch valve, directional valve one, throttle valve two, and two-way hydraulic control check valve. The piston rod of the front leveling cylinder retracts. At the same time, hydraulic oil enters the large chamber of the rear leveling cylinder through the switch valve, directional valve two, throttle valve four, and two-way hydraulic control check valve. The piston rod of the rear leveling cylinder extends, and the upper excavator rotates relative to the lower excavator, entering the leveling state.

[0013] Furthermore, when the switch valve is in the connected position, directional valve one is in the right position, and directional valve two is in the right position, hydraulic oil enters the large chamber of the front leveling cylinder through the switch valve, directional valve one, throttle valve one, and two-way hydraulic control check valve. The piston rod of the front leveling cylinder extends. At the same time, hydraulic oil enters the small chamber of the rear leveling cylinder through the switch valve, directional valve two, throttle valve three, and two-way hydraulic control check valve. The piston rod of the rear leveling cylinder retracts, and the upper excavator rotates relative to the lower excavator, entering the return-to-center state.

[0014] Furthermore, when the pressure value detected by pressure sensor 1 is less than the set pressure threshold 1, the switch valve is in the connected position and the directional valve 1 is in the right position. The hydraulic oil enters the large chamber of the front leveling cylinder through the switch valve, directional valve 1, throttle valve 1, and two-way hydraulic check valve to replenish the pressure of the front leveling cylinder until the pressure value detected by pressure sensor 1 is not less than the set pressure threshold 2.

[0015] Furthermore, when the pressure value detected by pressure sensor 2 is less than the set pressure threshold 1, the switch valve is in the connected position and the reversing valve 2 is in the left position. The hydraulic oil enters the large chamber of the rear leveling cylinder through the switch valve, reversing valve 2, throttle valve 4, and two-way hydraulic check valve to replenish the pressure of the rear leveling cylinder until the pressure value detected by pressure sensor 2 is not less than the set pressure threshold 2.

[0016] In a second aspect, an excavator is provided, the excavator being equipped with the excavator leveling control system described in the first aspect.

[0017] Compared with the prior art, the beneficial effects achieved by this utility model are as follows:

[0018] (1) This utility model uses a leveling cylinder that is hinged to the upper part of the excavator at one end and to the lower part of the excavator at the other end, and a leveling valve group that is connected to the front leveling cylinder and the rear leveling cylinder respectively. The working port 1 of the leveling valve group is connected to the large cavity of the front leveling cylinder, the working port 2 is connected to the small cavity of the front leveling cylinder, the working port 3 is connected to the large cavity of the rear leveling cylinder, and the working port 4 is connected to the small cavity of the rear leveling cylinder. Two-way hydraulic control check valves are installed on the hydraulic pipeline between the leveling valve group and the front leveling cylinder and the hydraulic pipeline between the leveling valve group and the rear leveling cylinder. The pressure of the leveling cylinder can be kept stable for a long time, thereby ensuring the leveling stability of the upper part of the excavator.

[0019] (2) This utility model detects the pressure in the large chamber of the leveling cylinder by means of a pressure sensor. When the pressure is lower than a certain value, pressure is added to the large chamber of the leveling cylinder to realize automatic detection and automatic pressure replenishment of the pressure in the large chamber of the leveling cylinder.

[0020] (3) This utility model can control the upper excavator to perform stepless leveling within a certain angle range relative to the lower excavator by using the tilt angle sensors of the upper and lower excavators and the throttle valve in the leveling valve group. Attached Figure Description

[0021] Figure 1 This is a diagram of the leveling structure in existing technology;

[0022] Figure 2 This is a schematic diagram of the principle of a leveling control system for an excavator upper structure provided in an embodiment of this utility model;

[0023] Figure 3 This is a schematic diagram of the overall vehicle layout according to an embodiment of the present utility model;

[0024] Figure 4 This is a leveling control logic diagram in an embodiment of this utility model;

[0025] In the diagram: V1, Switch valve; V2, Directional control valve 1; V3, Directional control valve 2; V4, Relief valve 1; V5, Throttle valve 1; V6, Throttle valve 2; V7, Throttle valve 3; V8, Throttle valve 4; V9, Relief valve 2; V10, Two-way hydraulic check valve 1; V11, Two-way hydraulic check valve 2; V12, Two-way hydraulic check valve 3; V13, Two-way hydraulic check valve 4; F1, Pressure sensor 1; F2, Pressure sensor 2. Detailed Implementation

[0026] The present invention will be further described below with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and should not be used to limit the scope of protection of the present invention.

[0027] Example 1

[0028] like Figures 1-4 As shown, a leveling control system for an excavator upper carriage includes: a leveling cylinder with one end hinged to the excavator upper carriage and the other end hinged to the excavator lower carriage; the leveling cylinder includes a front leveling cylinder located at the front of the excavator and a rear leveling cylinder located at the rear of the excavator; a leveling valve assembly connected to the front and rear leveling cylinders respectively; the working port 1 of the leveling valve assembly is connected to the large chamber of the front leveling cylinder, the working port 2 is connected to the small chamber of the front leveling cylinder, the working port 3 is connected to the large chamber of the rear leveling cylinder, and the working port 4 is connected to the small chamber of the rear leveling cylinder; and a two-way hydraulically controlled check valve is installed on the hydraulic lines between the leveling valve assembly and the front leveling cylinder, and on the hydraulic lines between the leveling valve assembly and the rear leveling cylinder.

[0029] like Figures 1-3As shown, this utility model includes two front leveling cylinders and two rear leveling cylinders. The hydraulic lines of the two front leveling cylinders are respectively equipped with a bidirectional hydraulic control check valve (V10) and a bidirectional hydraulic control check valve (V11), while the hydraulic lines of the two rear leveling cylinders are respectively equipped with a bidirectional hydraulic control check valve (V12) and a bidirectional hydraulic control check valve (V13). The bidirectional hydraulic control check valves can maintain the pressure of the leveling cylinders for extended periods, supporting the leveling mechanism and the upper part of the excavator. Alternatively, the bidirectional hydraulic control check valves can be replaced with bidirectional balance valves, which can also maintain the pressure in the large and small chambers of the leveling cylinders for a long time. Pressure sensor F1 is used to detect the pressure in the large chamber of the front leveling cylinder. Pressure sensor F2 is used to detect the pressure in the large chamber of the rear leveling cylinder. Tilt sensor I is used to detect the angle between the upper part of the excavator and the horizontal plane, and tilt sensor II is used to detect the angle between the lower part of the excavator and the horizontal plane. The leveling angle can be controlled by detecting the angles of the upper and lower parts relative to the horizontal ground.

[0030] The leveling valve assembly includes: a switching valve V1, the inlet of which is connected to the inlet of the leveling valve assembly, and the outlet of which is connected to the inlet of directional valve one V2 and the inlet of directional valve two V3 respectively; the outlet one of directional valve one V2 is connected to the working port one of the leveling valve assembly through throttle valve one V5; the outlet two of directional valve one V2 is connected to the working port two of the leveling valve assembly through throttle valve two V6; the outlet one of directional valve two V3 is connected to the working port four of the leveling valve assembly through throttle valve three V7; and the outlet two of directional valve two V3 is connected to the working port three of the leveling valve assembly through throttle valve four V8.

[0031] Relief valve 1 V4 is connected in parallel with throttle valve 1 V5, and relief valve 2 V9 is connected in parallel with throttle valve 4 V8; relief valve 1 V4 and relief valve 2 V9 are used to protect the system safety.

[0032] Switch valve V1 is a two-position, two-way directional control valve, serving as the switch for the leveling control system. Directional control valves V2 and V3 are three-position, four-way directional control valves, controlling the reversing of the front and rear leveling cylinders. Throttle valves V5, V6, V7, and V8 control the hydraulic oil flow rate to prevent excessive leveling speed and improve the excavator's leveling stability. Two-way hydraulic control check valves V10 to V13 maintain stable pressure in the large and small chambers of the leveling cylinders over extended periods.

[0033] When the leveling cylinder is stationary in any position, the electromagnet Y1 of the switching valve V1, the electromagnets Y2 and Y3 of the reversing valve one V2, and the electromagnets Y4 and Y5 of the reversing valve two V3 are all de-energized.

[0034] When electromagnets Y1, Y2, and Y4 are energized, switch valve V1 is in the connected position, directional valve one V2 is in the left position, and directional valve two V3 is in the left position. Hydraulic oil enters the small chamber of the front leveling cylinder through switch valve V1, directional valve one V2, throttle valve two V6, and the two-way hydraulic control check valve. The piston rod of the front leveling cylinder retracts. At the same time, hydraulic oil enters the large chamber of the rear leveling cylinder through switch valve V1, directional valve two V3, throttle valve four V8, and the two-way hydraulic control check valve. The piston rod of the rear leveling cylinder extends, and the upper excavator rotates relative to the lower excavator, entering the leveling state.

[0035] When electromagnets Y1, Y3, and Y5 are energized, switch valve V1 is in the connected position, directional valve one V2 is in the right position, and directional valve two V3 is in the right position. Hydraulic oil enters the large chamber of the front leveling cylinder through switch valve V1, directional valve one V2, throttle valve one V5, and the two-way hydraulic control check valve. The piston rod of the front leveling cylinder extends. At the same time, hydraulic oil enters the small chamber of the rear leveling cylinder through switch valve V1, directional valve two V3, throttle valve three V7, and the two-way hydraulic control check valve. The piston rod of the rear leveling cylinder retracts, and the upper excavator rotates relative to the lower excavator, entering the return-to-center state.

[0036] When the pressure value detected by pressure sensor F1 is less than the set pressure threshold 1 (set to 200 bar in this invention), the electromagnet Y1 of the switching valve V1 is energized, and the switching valve V1 is in the connected position. The electromagnet Y3 of the reversing valve V2 is energized, and the reversing valve V2 is in the right position. The hydraulic oil enters the large chamber of the front leveling cylinder through the switching valve V1, the reversing valve V2, the throttle valve V5, and the two-way hydraulic control check valve to replenish the pressure of the front leveling cylinder until the pressure value detected by pressure sensor F1 is not less than the set pressure threshold 2 (set to 300 bar in this invention). Then, electromagnet Y1 and electromagnet Y3 are de-energized.

[0037] When the pressure value detected by pressure sensor F2 is less than the set pressure threshold 1, the solenoid Y1 of the switching valve V1 is energized, and the switching valve V1 is in the connected position. The solenoid Y4 of the reversing valve V3 is energized, and the reversing valve V3 is in the left position. The hydraulic oil enters the large chamber of the rear leveling cylinder through the switching valve V1, the reversing valve V3, the throttle valve V8, and the two-way hydraulic check valve to replenish the pressure of the rear leveling cylinder until the pressure value detected by pressure sensor F2 is not less than the set pressure threshold 2. Then, the solenoid Y1 and the solenoid Y4 are de-energized.

[0038] In this invention, the large and small chambers of the two sets of front leveling cylinders are interconnected, ensuring equal pressure in both chambers and avoiding uneven force distribution due to unequal pressure. Similarly, the large and small chambers of the two sets of rear leveling cylinders are interconnected, ensuring equal pressure in both chambers and avoiding uneven force distribution due to unequal pressure.

[0039] Example 2

[0040] Based on the excavator upper leveling control system described in Embodiment 1, this embodiment provides an excavator equipped with the excavator upper leveling control system described in Embodiment 1.

[0041] The above description is only a preferred embodiment of the present utility model. 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 the present utility model, and these improvements and modifications should also be considered within the protection scope of the present utility model.

Claims

1. A backhoe loader on-vehicle leveling control system, characterized by, include: A leveling cylinder, one end of which is hinged to the upper part of the excavator and the other end of which is hinged to the lower part of the excavator, the leveling cylinder including a front leveling cylinder located at the front of the excavator and a rear leveling cylinder located at the rear of the excavator. The leveling valve group is connected to the front leveling cylinder and the rear leveling cylinder respectively. The working port 1 of the leveling valve group is connected to the large chamber of the front leveling cylinder, the working port 2 is connected to the small chamber of the front leveling cylinder, the working port 3 is connected to the large chamber of the rear leveling cylinder, and the working port 4 is connected to the small chamber of the rear leveling cylinder. Two-way hydraulic control check valves are installed on the hydraulic lines between the leveling valve assembly and the front leveling cylinder, as well as on the hydraulic lines between the leveling valve assembly and the rear leveling cylinder.

2. The excavator upper structure leveling control system of claim 1, wherein, It also includes pressure sensor 1 (F1) for detecting the pressure in the large chamber of the front leveling cylinder and pressure sensor 2 (F2) for detecting the pressure in the large chamber of the rear leveling cylinder.

3. The excavator upper structure leveling control system of claim 2, wherein, It also includes tilt sensor 1 for detecting the angle between the excavator's upper carriage and the horizontal plane, and tilt sensor 2 for detecting the angle between the excavator's lower carriage and the horizontal plane.

4. The excavator upper structure leveling control system of claim 3, wherein, The leveling valve assembly includes: a switching valve (V1), the inlet of which is connected to the inlet of the leveling valve assembly, and the outlet of which is connected to the inlet of directional valve one (V2) and the inlet of directional valve two (V3), respectively; the outlet one of directional valve one (V2) is connected to the working port one of the leveling valve assembly through throttle valve one (V5), the outlet two of directional valve one (V2) is connected to the working port two of the leveling valve assembly through throttle valve two (V6), the outlet one of directional valve two (V3) is connected to the working port four of the leveling valve assembly through throttle valve three (V7), and the outlet two of directional valve two (V3) is connected to the working port three of the leveling valve assembly through throttle valve four (V8).

5. The excavator upper structure leveling control system of claim 4, wherein, The leveling valve assembly also includes: overflow valve one (V4) and overflow valve two (V9), overflow valve one (V4) is connected in parallel with throttle valve one (V5), and overflow valve two (V9) is connected in parallel with throttle valve four (V8).

6. The excavator upper structure leveling control system of claim 4, wherein, When the switch valve (V1) is in the connected position, the directional valve one (V2) is in the left position, and the directional valve two (V3) is in the left position, the hydraulic oil enters the small chamber of the front leveling cylinder through the switch valve (V1), the directional valve one (V2), the throttle valve two (V6), and the two-way hydraulic control check valve. The piston rod of the front leveling cylinder retracts. At the same time, the hydraulic oil enters the large chamber of the rear leveling cylinder through the switch valve (V1), the directional valve two (V3), the throttle valve four (V8), and the two-way hydraulic control check valve. The piston rod of the rear leveling cylinder extends, and the upper excavator rotates relative to the lower excavator, entering the leveling state.

7. The excavator upper vehicle leveling control system according to claim 4, characterized in that, When the switch valve (V1) is in the connected position, the directional valve one (V2) is in the right position, and the directional valve two (V3) is in the right position, the hydraulic oil enters the large chamber of the front leveling cylinder through the switch valve (V1), the directional valve one (V2), the throttle valve one (V5), and the two-way hydraulic control check valve. The piston rod of the front leveling cylinder extends. At the same time, the hydraulic oil enters the small chamber of the rear leveling cylinder through the switch valve (V1), the directional valve two (V3), the throttle valve three (V7), and the two-way hydraulic control check valve. The piston rod of the rear leveling cylinder retracts, and the excavator upper vehicle rotates relative to the excavator lower vehicle, entering the return-to-center state.

8. The excavator upper structure leveling control system of claim 4, wherein, When the pressure value detected by pressure sensor 1 (F1) is less than the set pressure threshold 1, the switch valve (V1) is in the connected position and the directional valve 1 (V2) is in the right position. The hydraulic oil enters the large chamber of the front leveling cylinder through the switch valve (V1), directional valve 1 (V2), throttle valve 1 (V5), and two-way hydraulic check valve to replenish the pressure of the front leveling cylinder until the pressure value detected by pressure sensor 1 (F1) is not less than the set pressure threshold 2.

9. The excavator upper structure leveling control system of claim 4, wherein, When the pressure value detected by pressure sensor 2 (F2) is less than the set pressure threshold 1, the switch valve (V1) is in the connected position and the reversing valve 2 (V3) is in the left position. The hydraulic oil enters the large chamber of the rear leveling cylinder through the switch valve (V1), reversing valve 2 (V3), throttle valve 4 (V8), and two-way hydraulic check valve to replenish the pressure of the rear leveling cylinder until the pressure value detected by pressure sensor 2 (F2) is not less than the set pressure threshold 2.

10. An excavator characterized by comprising: The excavator is equipped with the excavator leveling control system as described in any one of claims 1 to 9.

Images