Hydraulic system of concrete pump truck and concrete pump truck

Abstract

The utility model discloses a hydraulic system of a concrete pump truck and the concrete pump truck. The hydraulic system comprises a controller, a hydraulic oil tank, a gear pump, a pilot-operated overflow valve, a pressure sensor, a reversing valve, an energy accumulator and a swing oil cylinder. When the pressure of the energy accumulator is larger than a first set value, the pilot-operated type overflow valve is powered on, a main valve element of the pilot-operated type overflow valve is unloaded, and an outlet of the gear pump and a hydraulic oil tank channel are communicated. And when the pressure of the energy accumulator is smaller than a second set value, the pilot-operated overflow valve loses power, and an outlet of the gear pump and a hydraulic oil tank passage are closed. According to the hydraulic system, the gear pump is used for providing a pressure oil source, the pressure sensor is used for detecting the pressure of the hydraulic system, unloading of the pilot-operated type overflow valve is controlled through a controller program, normal work of the hydraulic system is guaranteed, and meanwhile the situation that the pressure of the system is too high or too low is avoided. And the pumping capacity and efficiency of the hydraulic system of the concrete pump truck are ensured.

Description

Technical Field

[0001] The utility model relates to the technical field of concrete pump trucks, in particular to a hydraulic system of a concrete pump truck and the concrete pump truck. Background Art

[0002] When a concrete pump truck is operating, its hydraulic system typically uses pressurized oil to propel the cylinder piston back and forth, achieving concrete suction and delivery. The pumping and reversing hydraulic systems play a major role in the operation of a concrete pump truck. The reversing hydraulic system typically utilizes a constant-pressure pump in conjunction with an accumulator, enabling rapid reversing and minimal hydraulic shock, improving pumping stability and efficient delivery. However, the reversing hydraulic system has a complex structure, high manufacturing requirements, and is expensive. It is also sensitive to contamination from the hydraulic medium and requires high technical skills for operation and maintenance. Utility Model Content

[0003] In order to overcome at least one of the defects described in the above-mentioned prior art, the utility model provides a hydraulic system of a concrete pump truck, which adopts a gear pump to provide a pressure oil source, and a pressure sensor to detect the pressure of the reversing hydraulic system. By controlling the unloading of the pilot relief valve, the hydraulic system is ensured to operate normally without the system pressure being too high or too low, thereby ensuring the pumping capacity and efficiency of the hydraulic system of the concrete pump truck.

[0004] In order to overcome at least one of the defects of the prior art described above, the present invention further provides a concrete pump truck. The concrete pump truck uses the hydraulic system of the concrete pump truck described above, so that the concrete pump truck can maintain efficient and stable pumping capabilities.

[0005] The technical solution adopted by the present invention to solve the problem is:

[0006] A hydraulic system of a concrete pump truck includes a controller, a hydraulic oil tank, a gear pump, a pilot relief valve, a pressure sensor, a reversing valve, an accumulator and two swing cylinders;

[0007] The inlet of the gear pump is communicated with the hydraulic oil tank;

[0008] The inlet of the pilot-operated relief valve is connected to the outlet of the gear pump, and the outlet of the pilot-operated relief valve is connected to the hydraulic oil tank;

[0009] The outlet of the reversing valve is connected to the inlet of the swing cylinder;

[0010] The pressure sensor is in signal communication with the controller, and the pressure sensor obtains the accumulator pressure;

[0011] The pressure sensor obtains the accumulator pressure; when the accumulator pressure is greater than a first set value, the pilot relief valve connects the gear pump outlet and the hydraulic oil tank passage; when the accumulator pressure is less than a second set value, the pilot relief valve closes the gear pump outlet and the hydraulic oil tank passage; the first set value is greater than the second set value.

[0012] Furthermore: the reversing valve has an electromagnetic reversing valve and a hydraulically controlled reversing valve, the electromagnetic reversing valve control oil acts on the two ends of the hydraulically controlled reversing valve valve core respectively, the swing cylinder has a first oil port, and the first oil ports of the two swing cylinders are both connected to the oil outlet of the reversing valve.

[0013] Furthermore: the oil port of the accumulator is connected to the inlet of the reversing valve.

[0014] Furthermore, the oil port of the accumulator is also connected to a unloading ball valve, and the outlet of the unloading ball valve is connected to the hydraulic oil tank.

[0015] Furthermore: the pilot-operated relief valve has a solenoid valve, and the solenoid valve controls the on-off of the main valve core of the pilot-operated relief valve.

[0016] Furthermore: the pressure sensor obtains the accumulator pressure. In the standby state or the pumping state, when the accumulator pressure is greater than the first set value, the pilot overflow valve is energized and the main valve core of the pilot overflow valve is unloaded, thereby connecting the outlet of the gear pump and the hydraulic oil tank passage; when the accumulator pressure is less than the second set value, the pilot overflow valve loses power and closes the outlet of the gear pump and the hydraulic oil tank passage.

[0017] Furthermore, the swing cylinder also has a second oil port, and the second oil ports of the two swing cylinders are both connected to the hydraulic oil tank.

[0018] Furthermore, the hydraulic system of the concrete pump truck further includes a one-way valve, the inlet of the one-way valve is connected to the outlet of the gear pump, and the outlet of the one-way valve is connected to the oil port of the accumulator and the inlet of the reversing valve.

[0019] Furthermore, the hydraulic system of the concrete pump truck further includes a pressure gauge, which is arranged at the oil port of the accumulator.

[0020] A concrete pump truck comprises the hydraulic system of the concrete pump truck mentioned above.

[0021] In summary, the hydraulic system of a concrete pump truck provided by the present invention has the following technical effects:

[0022] The gear pump features a simple and compact structure, stable flow, and is suitable for applications requiring stable flow. It is also relatively affordable and highly resistant to hydraulic oil contamination. Furthermore, by combining the gear pump with a pressure sensor, the pressure sensor acquires the accumulator pressure, thereby acquiring the pressure of the hydraulic system. By controlling the unloading of the pilot-operated relief valve, feedback control is provided to the concrete pump truck's hydraulic system, ensuring that the hydraulic system operates within the set pressure range, avoiding excessive or insufficient pressure, and achieving smooth and efficient pumping.

[0023] To sum up, the concrete pump truck provided by the utility model has the following technical effects: the hydraulic system of the aforementioned concrete pump truck is used on the concrete pump truck, so that the concrete pump truck can maintain efficient and stable pumping capabilities. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 The utility model is a schematic diagram of the hydraulic system of a concrete pump truck.

[0025] Figure 2 This is a first working schematic diagram of the hydraulic system of a concrete pump truck in the utility model in a pumping state.

[0026] Figure 3 This is a second working schematic diagram of the hydraulic system of a concrete pump truck in the utility model in a pumping state.

[0027] Figure 4 This is a first working schematic diagram of the hydraulic system of a concrete pump truck in a standby state according to the utility model.

[0028] Figure 5 This is a second working schematic diagram of the hydraulic system of a concrete pump truck in the standby state according to the utility model.

[0029] The meanings of the reference numerals are as follows:

[0030] 1. Hydraulic oil tank; 2. Gear pump; 3. Pressure gauge; 4. Check valve; 5. Unloading ball valve; 6. Accumulator; 7. Pilot-operated relief valve; 71. Solenoid valve; 8. Reversing valve; 81. Solenoid reversing valve; 82. Hydraulic-controlled reversing valve; 9. Swing cylinder; 10. Pressure sensor. DETAILED DESCRIPTION

[0031] For better understanding and implementation, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0032] In the description of the present invention, it should be noted that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they cannot be understood as limiting the present invention.

[0033] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0034] See Figure 1 The utility model discloses a hydraulic system of a concrete pump truck.

[0035] A hydraulic system of a concrete pump truck includes a controller, a hydraulic oil tank 1, a gear pump 2, a pilot-operated overflow valve 7, a pressure sensor 10, a reversing valve 8, an accumulator 6, and a swing cylinder 9.

[0036] The inlet of the gear pump 2 is communicated with the hydraulic oil tank 1 .

[0037] The inlet of the pilot-operated relief valve 7 is connected to the outlet of the gear pump 2 , and the outlet of the pilot-operated relief valve 7 is connected to the hydraulic oil tank 1 .

[0038] The outlet of the reversing valve 8 is connected to the inlet of the swing cylinder 9.

[0039] The pressure sensor 10 is connected to the controller signal, and the pressure sensor 10 obtains the pressure of the accumulator 6, that is, the pressure of the hydraulic system.

[0040] Pressure sensor 10 detects the pressure in accumulator 6. When the pressure in accumulator 6 exceeds a first set value, solenoid valve 71 is energized, unloading the main spool of pilot-operated relief valve 7. Pilot-operated relief valve 7 then opens the passage between the outlet of gear pump 2 and hydraulic oil tank 1. When the pressure in accumulator 6 falls below a second set value, solenoid valve 71 is de-energized, and pilot-operated relief valve 7 closes the passage between the outlet of gear pump 2 and hydraulic oil tank 1. The first set value is greater than the second set value.

[0041] When the hydraulic system is working, in the pumping state, the gear pump 2 delivers hydraulic oil to the accumulator 6 and the reversing valve 8, and finally the hydraulic oil enters the swing cylinder 9 through the reversing valve 8, driving the swing cylinder 9 to work and realize the pumping function.

[0042] The specific working process is as follows: Figure 1In the pumping state, the pressure oil of gear pump 2 enters the reversing valve 8 and accumulator 6. When DT1 on the electromagnetic reversing valve 81 is energized, the electromagnet pushes the valve core of the electromagnetic reversing valve 81 to the right. The pilot oil acts on the left end of the valve core of the hydraulic control reversing valve 82, pushing the valve core of the hydraulic control reversing valve 82 to the right. Then the pressure oil enters the rodless chamber of the swing cylinder 9R from port B, pushing the piston rod of the swing cylinder 9R to extend; the piston rod of the other swing cylinder 9L retracts, and the hydraulic oil in its rodless chamber returns to the hydraulic oil tank 1 through the reversing valve 8. Figure 2 In the figure, the thick solid line shows the pressure oil circuit, the double-dash line shows the pilot oil circuit, and the single-dash line shows the return oil circuit.

[0043] Similarly, in the pumping state, the pressure oil of gear pump 2 enters the reversing valve 8 and accumulator 6. When DT2 on the electromagnetic reversing valve 81 is energized, the electromagnet pushes the valve core of the electromagnetic reversing valve 81 to the left, and the pilot oil acts on the right end of the valve core of the hydraulic control reversing valve 82, pushing the valve core of the hydraulic control reversing valve 82 to the left. Then the pressure oil enters the rodless chamber of the swing cylinder 9L from port A, pushing the piston rod of the swing cylinder 9L to extend; the piston rod of the other swing cylinder 9R retracts, and the hydraulic oil in its rodless chamber returns to the hydraulic oil tank 1 through the reversing valve 8. Figure 2 In the figure, the thick solid line shows the pressure oil circuit, the double-dash line shows the pilot oil circuit, and the single-dash line shows the return oil circuit.

[0044] In the pumping state, the pressure value on the accumulator 6 obtained by the pressure sensor 10 is compared with the set pressure value:

[0045] Assume that the first set value is P1, the second set value is P2, and P1>P2; the pressure sensor 10 obtains the pressure P on the accumulator 6. When P>P1, that is, the real-time pressure value P of the hydraulic system obtained by the pressure sensor 10 is greater than the set maximum pressure value P1, the pressure of the hydraulic system needs to be controlled to prevent it from continuing to rise. Therefore, the solenoid valve 71 is energized, unloading the main valve core of the pilot relief valve 7, connecting the outlet of the gear pump 2 and the hydraulic oil tank 1, and the hydraulic oil of the gear pump 2 returns to the hydraulic oil tank 1 through the pilot relief valve 7. During this process, the hydraulic oil delivered by the gear pump 2 returns to the hydraulic oil tank 1 through the pilot relief valve 7, and the pressure oil in the accumulator 6 enters the swing cylinder 9 through the reversing valve 8 to work, thereby reducing the pressure on the accumulator 6.

[0046] Assume that the first set value is P1, the second set value is P2, and P1>P2; the pressure sensor 10 obtains the pressure on the accumulator 6 as P. As shown in Figure 2, when P<P2, that is, the real-time pressure value P of the hydraulic system obtained by the pressure sensor 10 is less than the set minimum pressure value P2, at this time, it is necessary to control the pressure of the hydraulic system to increase the system pressure. Therefore, the solenoid valve 71 loses power, closing the outlet of the gear pump 2 and the passage between the hydraulic oil tank 1, allowing the hydraulic oil output by the gear pump 2 to enter the reversing valve 8 and the accumulator 6, so that the pressure on the accumulator 6 increases, and the pressure oil enters the swing cylinder 9 through the reversing valve 8 to work, realizing the pumping operation.

[0047] As can be seen from the above technical solution, assuming that the first set value is P1 and the second set value is P2, and P1>P2; the pressure sensor 10 obtains the pressure on the accumulator 6 as P. When P<P2, the outlet of the gear pump 2 and the passage between the hydraulic oil tank 1 are closed, causing the system pressure to increase; when P>P1, the outlet of the gear pump 2 and the passage between the hydraulic oil tank 1 are open, causing the system pressure to decrease.

[0048] The above-described technical solution utilizes a gear pump 2 to deliver hydraulic oil, resulting in a simple and compact structure and stable flow rate, suitable for applications requiring stable flow rates. It is also relatively inexpensive and highly resistant to hydraulic oil contamination. Furthermore, the gear pump 2 is combined with a pressure sensor 10, which detects the pressure of the accumulator 6 and, therefore, the pressure of the hydraulic system. This controller program controls the unloading of the pilot-operated relief valve 7, providing feedback control of the concrete pump truck's hydraulic system, ensuring that the hydraulic system operates within the set pressure range, avoiding excessive or insufficient pressure, and achieving smooth and efficient pumping.

[0049] In the above technical solution, the pressure of the accumulator 6 is obtained in real time through the pressure sensor 10, that is, the pressure of the hydraulic system is obtained, and the flow direction of the hydraulic oil output by the gear pump 2 is controlled to ensure the pumping operation of the system, so that the hydraulic oil is delivered smoothly and the pumping operation is maintained efficiently.

[0050] In this technical solution, the reversing valve 8 comprises an electromagnetic reversing valve 81 and a hydraulically controlled reversing valve 82. The control oil of the electromagnetic reversing valve 81 acts on both ends of the valve core of the hydraulically controlled reversing valve 82. The swinging cylinder 9 has a first oil port. The first oil ports of both swinging cylinders are connected to the oil outlet of the reversing valve 8. The control of the reversing valve 8 is achieved through the electromagnetic reversing valve 81 and the hydraulically controlled reversing valve 82, which is fast, convenient, and precise.

[0051] In this technical solution, the swing cylinder 9 also has a second oil port, and the second oil ports of the two swing cylinders 9 are both connected to the hydraulic oil tank 1 to achieve oil return and oil replenishment.

[0052] In this technical solution, the oil port of the accumulator 6 is connected to the inlet of the reversing valve 8. The gear pump 2 fills the accumulator 6 with oil. During pumping, the oil in the accumulator 6 enters the swing cylinder 9 through the reversing valve 8 to realize pumping and ensure smooth pumping.

[0053] In this technical solution, the oil port of the accumulator 6 is also connected to the unloading ball valve 5, and the outlet of the unloading ball valve 5 is connected to the hydraulic oil tank 1. The function of the unloading ball valve 5 is to open the unloading ball valve 5 to release the high-pressure oil in the accumulator when the reversing hydraulic system components are repaired.

[0054] In this technical solution, the pilot-operated relief valve 7 includes a solenoid valve 71, which controls the opening and closing of the main valve core of the pilot-operated relief valve 7. Control via the solenoid valve 71 provides convenient and quick control. In this technical solution, a pressure sensor 10 detects the pressure of the accumulator 6. When the pressure of the accumulator 6 exceeds a first set value, the pilot-operated relief valve 7 opens the passage between the outlet of the gear pump 2 and the hydraulic oil tank 1. When the pressure of the accumulator 6 falls below a second set value, the pilot-operated relief valve 7 closes the passage between the outlet of the gear pump 2 and the hydraulic oil tank 1.

[0055] In the standby state, the reversing valve does not work and does not deliver hydraulic oil to the swing cylinder 9. However, part of the hydraulic oil delivered by the gear pump 2 will enter the accumulator 6 to charge the accumulator 6 and prepare for the rapid start of the pumping working state.

[0056] like Figure 4 As shown, assuming that the first set value is P1, the second set value is P2, and P1>P2; the pressure sensor 10 obtains the pressure on the accumulator 6 as P. As shown in Figure 4, when P>P1, that is, the real-time pressure value P of the hydraulic system obtained by the pressure sensor 10 is greater than the set maximum pressure value P1, at this time it is necessary to control the pressure of the hydraulic system to prevent it from continuing to rise, so the solenoid valve 71 is energized to unload the main valve core of the pilot relief valve 7, and connect the outlet of the gear pump 2 and the hydraulic oil tank 1. The hydraulic oil of the gear pump 2 returns to the hydraulic oil tank 1 through the pilot relief valve 7 to prevent the pressure in the accumulator 6 from being too high. Figure 4 In the figure, the thick solid line shows the system's pressure oil circuit in standby mode. At this time, the oil in accumulator 6 is connected to reversing valve 8, but reversing valve 8 does not deliver oil to swing cylinder 9. The dashed line shows the return oil circuit for the hydraulic oil delivered by gear pump 2 through pilot relief valve 7. During this process, all the hydraulic oil delivered by gear pump 2 returns to hydraulic oil tank 1 through pilot relief valve 7, preventing the pressure in accumulator 6 from further increasing.

[0057] like Figure 5As shown, assuming that the first set value is P1, the second set value is P2, and P1>P2; the pressure sensor 10 obtains the pressure on the accumulator 6 as P. As shown in Figure 5, when P<P2, that is, the real-time pressure value P of the hydraulic system obtained by the pressure sensor 10 is less than the set minimum pressure value P2, it is necessary to control the pressure of the hydraulic system to increase the system pressure. Therefore, the solenoid valve 71 loses power at this time, closing the outlet of the gear pump 2 and the passage of the hydraulic oil tank 1, so that the hydraulic oil output by the gear pump 2 enters the reversing valve 8 and the accumulator 6, but the reversing valve 8 will not deliver the pressurized oil to the swing cylinder 9 at this time. Figure 5 In the figure, the thick solid line shows the hydraulic oil circuit in the standby state, and the double-dotted line shows the pilot oil circuit.

[0058] In this technical solution, the hydraulic system of the concrete pump truck also includes a check valve 4. The inlet of check valve 4 is connected to the outlet of gear pump 2. The outlet of check valve 4 is connected to the oil port of accumulator 6 and the inlet of reversing valve 8. The function of check valve 4 is to prevent the pressurized oil in accumulator 6 from being discharged back to the hydraulic oil tank through pilot-operated relief valve 7 when the pilot-operated relief valve 7 is unloaded.

[0059] In this technical solution, the hydraulic system of the concrete pump truck also includes a pressure gauge 3, which is arranged at the oil port of the accumulator. The position of the pressure gauge 3 can quickly and clearly know the pressure value of the accumulator 6.

[0060] In the present technical solution, a concrete pump truck includes the aforementioned hydraulic system of the concrete pump truck, so that the concrete pump truck can maintain efficient and stable pumping capabilities.

[0061] The technical means disclosed in the present invention are not limited to those disclosed in the above-mentioned embodiments, but also include technical solutions composed of any combination of the above-mentioned technical features. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and such improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A hydraulic system for a concrete pump truck, characterized by: It includes a controller, a hydraulic oil tank, a gear pump, a pilot-operated relief valve, a pressure sensor, a reversing valve, an accumulator and two swing cylinders; The inlet of the gear pump is communicated with the hydraulic oil tank; The inlet of the pilot-operated relief valve is connected to the outlet of the gear pump, and the outlet of the pilot-operated relief valve is connected to the hydraulic oil tank; The outlet of the reversing valve is connected to the inlet of the swing cylinder; The pressure sensor is in signal communication with the controller, and the pressure sensor obtains the accumulator pressure; The pressure sensor obtains the accumulator pressure; when the accumulator pressure is greater than a first set value, the pilot relief valve connects the gear pump outlet and the hydraulic oil tank passage; when the accumulator pressure is less than a second set value, the pilot relief valve closes the gear pump outlet and the hydraulic oil tank passage; the first set value is greater than the second set value.

2. The hydraulic system of a concrete pump truck according to claim 1, characterized in that: The reversing valve has an electromagnetic reversing valve and a hydraulically controlled reversing valve. The control oil of the electromagnetic reversing valve acts on the two ends of the valve core of the hydraulically controlled reversing valve respectively. The swing cylinder has a first oil port. The first oil ports of the two swing cylinders are both connected to the oil outlet of the reversing valve.

3. The hydraulic system of a concrete pump truck according to claim 1, characterized in that: The oil port of the accumulator is communicated with the inlet of the reversing valve.

4. The hydraulic system of a concrete pump truck according to claim 1, characterized in that: The oil port of the accumulator is also connected to a unloading ball valve, and the outlet of the unloading ball valve is communicated with the hydraulic oil tank.

5. The hydraulic system of a concrete pump truck according to claim 1, characterized in that: The pilot-operated relief valve comprises a solenoid valve, which controls the on-off of a main valve core of the pilot-operated relief valve.

6. The hydraulic system of a concrete pump truck according to claim 1 or 5, characterized in that: The pressure sensor obtains the accumulator pressure. In the standby state or the pumping state, when the accumulator pressure is greater than a first set value, the pilot relief valve is energized and the main valve core of the pilot relief valve is unloaded, thereby connecting the outlet of the gear pump and the hydraulic oil tank passage; when the accumulator pressure is less than a second set value, the pilot relief valve is de-energized, closing the outlet of the gear pump and the hydraulic oil tank passage.

7. The hydraulic system of a concrete pump truck according to claim 2, characterized in that: The swing cylinder also has a second oil port, and the second oil ports of the two swing cylinders are both connected to the hydraulic oil tank.

8. The hydraulic system of a concrete pump truck according to claim 1, characterized in that: It also includes a one-way valve, the inlet of the one-way valve is connected to the outlet of the gear pump, and the outlet of the one-way valve is connected to the oil port of the accumulator and the inlet of the reversing valve.

9. The hydraulic system of a concrete pump truck according to claim 1, characterized in that: The device also includes a pressure gauge, which is arranged at the oil port of the accumulator.

10. A concrete pump truck, characterized in that: A hydraulic system for a concrete pump truck comprising any one of claims 1 to 9.

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