Aerial work platform and hydraulic leveling device thereof

Abstract

The utility model discloses an aerial work platform and a hydraulic leveling device thereof. The device comprises a sensor used for detecting the inclination angle of the aerial work platform, a controller, a leveling mechanism, a hydraulic oil tank and a locking valve. The sensor is in communication connection with the controller, the hydraulic oil tank is connected with a leveling valve of the leveling mechanism through a hydraulic pump, and a coil of the leveling valve is connected with the output end of the controller; the locking valve is arranged between the hydraulic pump and the leveling valve, the locking valve is further connected with the hydraulic oil tank, and power on and power off of a coil of the locking valve are controlled by the controller or the sensor. When the inclination angle exceeds the set angle, the aerial work platform is locked at the current position, and the overturning problem caused by continuous increase of the inclination angle of the aerial work platform is avoided.

Description

Technical Field

[0001] The utility model belongs to the technical field of leveling control, and in particular relates to an aerial work platform and a hydraulic leveling device thereof. Background Art

[0002] The aerial work platform is located at the top of the boom of the work vehicle. During the boom amplitude change process, the aerial work platform is in danger of becoming unbalanced and causing tilting or overturning as the boom moves. It must have an automatic leveling function to meet the needs of rescue or work and ensure the safety of the operators.

[0003] At present, the leveling of aerial work platforms usually adopts hydraulic leveling or electric leveling, and the tilt angle of the aerial work platform is detected by the inclination sensor and its leveling and protection are controlled. When the tilt angle exceeds the set angle, due to the lack of locking control function, the arm action can only be stopped by program control (i.e., the leveling output is turned off) and an alarm is sounded, and the leveling mechanism can actually still work; when there is a control (such as a program bug) or line (such as a short circuit between the line and the power supply) or hydraulic oil circuit abnormality (such as a stuck leveling valve), turning off the leveling output cannot turn off or close the hydraulic valve in time, causing the leveling cylinder to continue to extend and retract, and the tilt angle of the aerial work platform will continue to increase, causing the aerial work platform to tilt. Utility Model Content

[0004] The utility model aims to provide an aerial work platform and a hydraulic leveling device thereof, so as to solve the problem that when the tilt angle of the aerial work platform exceeds the set angle, the hydraulic valve cannot be closed or closed in time due to abnormal control or circuit or hydraulic oil circuit, thereby causing the leveling cylinder to continue to operate and cause the work platform to tilt.

[0005] The utility model solves the above technical problems through the following technical solutions: a hydraulic leveling device for an aerial work platform, comprising a sensor for detecting the tilt angle of the aerial work platform, a controller, a leveling mechanism and a hydraulic oil tank; the sensor is communicatively connected to the controller, the hydraulic oil tank is connected to the leveling valve of the leveling mechanism through a hydraulic pump, and the coil of the leveling valve is connected to the output end of the controller; the hydraulic leveling device also includes a locking valve;

[0006] The locking valve is arranged between the hydraulic pump and the leveling valve, and the locking valve is also connected to the hydraulic oil tank. The gain and loss of electricity of the coil of the locking valve is controlled by the controller or the sensor.

[0007] In the hydraulic leveling device of the utility model, when the tilt angle of the aerial work platform does not exceed the set angle, the controller or sensor controls the coil of the locking valve to be energized normally, and the pressure oil provided by the hydraulic pump enters the leveling valve through the locking valve. At the same time, the controller controls the extension and retraction of the leveling cylinder in the leveling mechanism by controlling the coil of the leveling valve to be energized, thereby realizing the leveling action of the aerial work platform; when the tilt angle of the aerial work platform exceeds the set angle, the controller or sensor controls the coil of the locking valve to lose power, and the pressure oil provided by the hydraulic pump directly flows back to the hydraulic oil tank through the locking valve, and the pressure of the hydraulic pipeline is zero. At this time, even if the leveling valve cannot be closed or closed in time, even if the leveling valve is actuated, since there is no pressure in the hydraulic pipeline, the leveling cylinder will not extend or retract, so that the aerial work platform is locked in the current position, thereby avoiding the overturning problem caused by the continuous increase in the tilt angle of the aerial work platform.

[0008] Furthermore, the locking valve is a switch valve or a two-position two-way solenoid valve.

[0009] Furthermore, the controller is a PLC controller.

[0010] Furthermore, the gain and loss of power of the coil of the locking valve is controlled by the sensor through a first relay module, the contacts of the first relay module are connected in series with the coil of the locking valve, and the gain and loss of power of the coil of the first relay module is controlled by a processing unit of the sensor.

[0011] When the tilt angle of the aerial work platform does not exceed the set angle, the processing unit of the sensor controls the contact of the first relay module to close by controlling the coil of the first relay module to be energized, so that the coil of the locking valve is energized; when the tilt angle of the aerial work platform exceeds the set angle, the processing unit of the sensor controls the contact of the first relay module to open by controlling the coil of the first relay module to be de-energized, so that the coil of the locking valve is de-energized.

[0012] Furthermore, the first relay module includes two relays connected in series.

[0013] Further, when the gain and loss of power of the coil of the locking valve is controlled by the controller, the input end of the controller is also connected to the contact of the second relay module, and the gain and loss of power of the coil of the second relay module is controlled by the processing unit of the sensor.

[0014] When the tilt angle of the aerial work platform does not exceed the set angle, the processing unit of the sensor controls the closing of the contacts of the second relay module by controlling the coil of the second relay module to be energized, and the controller controls the coil of the locking valve to be energized according to the contact closure signal of the second relay module; when the tilt angle of the aerial work platform exceeds the set angle, the processing unit of the sensor controls the disconnection of the contacts of the second relay module by controlling the coil of the second relay module to be de-energized, and the controller controls the coil of the locking valve to be de-energized according to the contact disconnection signal of the second relay module.

[0015] Furthermore, the second relay module includes two relays connected in series.

[0016] Furthermore, the sensor is communicatively connected to the controller via a CAN bus.

[0017] Based on the same concept, the utility model also provides an aerial work platform, including the hydraulic leveling device as described above.

[0018] Beneficial Effects

[0019] Compared with the prior art, the advantages of the utility model are:

[0020] The utility model adds a locking valve on the basis of the original leveling device. When the tilt angle does not exceed the set angle, the coil of the locking valve is energized, and the pressure oil provided by the hydraulic pump enters the leveling valve normally through the locking valve to realize the leveling function; when the tilt angle exceeds the set angle, the coil of the control locking valve loses power, and the pressure oil provided by the hydraulic pump directly flows back to the hydraulic oil tank through the locking valve, and the pressure of the hydraulic pipeline is zero. Even if the control program, circuit or hydraulic oil circuit is abnormal, the leveling cylinder cannot be extended or retracted due to the lack of pressure in the hydraulic pipeline, so that the aerial work platform is locked in the current position, avoiding the overturning problem caused by the continuous increase of the tilt angle of the aerial work platform. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solution of the present invention, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only one embodiment of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0022] Figure 1 1 is an electrical control schematic diagram of the hydraulic leveling device in Example 1 of the utility model; wherein V+ / V- represents the power supply terminal of the inclination sensor or controller, I1 represents the input terminal of the controller, O1 / O2 / O3 represents the output terminal of the controller, CANH / CANL represents the communication terminal of the inclination sensor or controller, YV2 / YV3 represents the coil of the leveling valve, YV1 represents the coil of the locking valve, and G1 represents the power supply;

[0023] Figure 2 It is a structural schematic diagram of the hydraulic leveling device in Embodiment 1 of the present utility model;

[0024] Figure 3 This is the electrical control principle diagram of the hydraulic leveling device in Embodiment 2 of the present utility model; wherein S1 / S2 represents the contacts of the relay;

[0025] Figure 4This is the electrical control principle diagram of the hydraulic leveling device in Example 3 of the utility model.

[0026] Explanation of the reference numerals: 1 - inclination sensor, 2 - controller, 3 - locking valve, 31 - coil of locking valve, 4 - leveling valve, 41 / 42 - coil of leveling valve, 5 - leveling cylinder, 6 - hydraulic oil tank, 7 - hydraulic pump. DETAILED DESCRIPTION

[0027] The following is a clear and complete description of the technical solution in the utility model in conjunction with the drawings in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0028] Example 1

[0029] like Figure 1 and Figure 2 As shown, a hydraulic leveling device for an aerial work platform provided in this embodiment includes an inclination sensor 1, a controller 2, a leveling mechanism, a hydraulic oil tank 6 and a locking valve 3; the inclination sensor 1 is connected to the controller 2 via a CAN bus communication to transmit the inclination angle of the aerial work platform detected by the inclination sensor 1 to the controller 2; the hydraulic oil tank 6 is connected to the leveling valve 4 of the leveling mechanism via a hydraulic pump 7, the coil 41 / 42 of the leveling valve is connected to the output end of the controller 2, and the controller 2 controls the gain and loss of electricity of the coil 41 / 42 of the leveling valve; the locking valve 3 is arranged between the hydraulic pump 7 and the leveling valve 4, the locking valve 3 is also connected to the hydraulic oil tank 6, the coil 31 of the locking valve is connected to the output end of the controller 2, and the controller 2 controls the gain and loss of electricity of the coil 31 of the locking valve.

[0030] The controller 2 receives the tilt angle of the aerial work platform transmitted by the tilt sensor 1, and determines whether the tilt angle of the aerial work platform exceeds the set angle; when the tilt angle of the aerial work platform does not exceed the set angle, the controller 2 directly controls the coil 31 of the locking valve to be energized normally, and the pressure oil provided by the hydraulic pump 7 enters the leveling valve 4 through the locking valve 3. At the same time, the controller 2 controls the coil 41 / 42 of the leveling valve to be energized to control the extension and retraction of the leveling cylinder 5 in the leveling mechanism to achieve the leveling action of the aerial work platform; when the tilt angle of the aerial work platform exceeds the set angle, the controller 2 directly controls the coil 31 of the locking valve to lose power, and the pressure oil provided by the hydraulic pump 7 flows directly back to the hydraulic oil tank 6 through the locking valve 3, and the hydraulic pipeline pressure is zero. At this time, even if the leveling valve 4 cannot be closed or closed in time, even if the leveling valve 4 is actuated, since there is no pressure in the hydraulic pipeline, the leveling cylinder 5 will not extend or retract, so that the aerial work platform is locked in the current position, avoiding the overturning problem caused by the continuous increase in the tilt angle of the aerial work platform.

[0031] In the embodiment of the utility model, the locking valve 3 is a switch valve or a two-position two-way solenoid valve; and the controller 2 is a PLC controller 2 .

[0032] Example 2

[0033] like Figure 2 and Figure 3 As shown, a hydraulic leveling device for an aerial work platform provided in this embodiment includes an inclination sensor 1, a controller 2, a leveling mechanism, a hydraulic oil tank 6, a first relay module and a locking valve 3; the inclination sensor 1 is connected to the controller 2 via a CAN bus communication to transmit the inclination angle of the aerial work platform detected by the inclination sensor 1 to the controller 2; the hydraulic oil tank 6 is connected to the leveling valve 4 of the leveling mechanism via a hydraulic pump 7, and the coil 41 / 42 of the leveling valve is connected to the output end of the controller 2, and the controller 2 controls the gain and loss of electricity of the coil 41 / 42 of the leveling valve; the locking valve 3 is arranged between the hydraulic pump 7 and the leveling valve 4, and the locking valve 3 is also connected to the hydraulic oil tank 6, the coil 31 of the locking valve is connected in series with the contacts of the first relay module, and the coil of the first relay module is connected to the output end of the processing unit of the inclination sensor 1, that is, the gain and loss of electricity of the coil of the first relay module is controlled by the processing unit of the inclination sensor 1.

[0034] The inclination sensor 1 includes a detection unit and a processing unit. The detection unit is used to detect the inclination angle, and the processing unit is used to determine whether the inclination angle detected by the detection unit exceeds the set angle, and transmit the inclination angle to the controller 2. The controller 2 receives the inclination angle of the aerial work platform transmitted by the inclination sensor 1, and determines whether the inclination angle of the aerial work platform exceeds the set angle; when the inclination angle of the aerial work platform does not exceed the set angle, the processing unit of the sensor controls the closure of the contacts of the first relay module by controlling the coil of the first relay module to be energized, so that the coil 31 of the locking valve is energized, and the pressure oil provided by the hydraulic pump 7 enters the leveling valve 4 through the locking valve 3. At the same time, the controller 2 controls the extension and retraction of the leveling cylinder 5 in the leveling mechanism by controlling the coil 41 / 42 of the leveling valve to be energized, thereby realizing the leveling action of the aerial work platform. When the tilt angle of the aerial work platform exceeds the set angle, the processing unit of the sensor controls the contact of the first relay module to disconnect by controlling the coil of the first relay module to lose power, so that the coil 31 of the locking valve loses power, and the pressure oil provided by the hydraulic pump 7 flows directly back to the hydraulic oil tank 6 through the locking valve 3, and the pressure of the hydraulic pipeline is zero. At this time, even if the leveling valve 4 cannot be closed or closed in time, even if the leveling valve 4 is activated, since there is no pressure in the hydraulic pipeline, the leveling cylinder 5 will not extend or retract, so that the aerial work platform is locked in the current position, avoiding the overturning problem caused by the continuous increase in the tilt angle of the aerial work platform.

[0035] The controller 2 can control the power supply and loss of the coil 41 / 42 of the leveling valve according to the judgment result of whether the inclination angle of the aerial work platform exceeds the set angle, or the series branch of the contact of the first relay module and the coil 31 of the locking valve is connected to the input end of the controller 2, and the controller 2 controls the power supply and loss of the coil 41 / 42 of the leveling valve according to the disconnection or connection of the series branch.

[0036] This embodiment uses the inclination sensor 1 to control the power supply and loss supply of the coil 31 of the locking valve through the first relay module, thereby reducing the control link of the locking valve 3, enabling timely locking control, avoiding the control link transmission problem that causes the locking control to fail, and having higher reliability.

[0037] In an embodiment of the utility model, the first relay module includes two relays connected in series to achieve redundancy and have higher reliability.

[0038] Example 3

[0039] like Figure 2 and Figure 4As shown, a hydraulic leveling device for an aerial work platform provided in this embodiment includes an inclination sensor 1, a controller 2, a leveling mechanism, a hydraulic oil tank 6, a second relay module and a locking valve 3; the inclination sensor 1 is connected to the controller 2 via a CAN bus communication to transmit the inclination angle of the aerial work platform detected by the inclination sensor 1 to the controller 2; the hydraulic oil tank 6 is connected to the leveling valve 4 of the leveling mechanism via a hydraulic pump 7, the coil 41 / 42 of the leveling valve is connected to the output end of the controller 2, and the controller 2 controls the gain and loss of electricity of the coil 41 / 42 of the leveling valve; the locking valve 3 is arranged between the hydraulic pump 7 and the leveling valve 4, the locking valve 3 is also connected to the hydraulic oil tank 6, the coil 31 of the locking valve is connected to the output end of the controller 2, and the controller 2 controls the gain and loss of electricity of the coil 31 of the locking valve; the input end of the controller 2 is also connected to the contact of the second relay module, and the gain and loss of electricity of the coil of the second relay module is controlled by the processing unit of the sensor.

[0040] The inclination sensor 1 includes a detection unit and a processing unit. The detection unit is used to detect the inclination angle, and the processing unit is used to determine whether the inclination angle detected by the detection unit exceeds the set angle, and transmit the inclination angle to the controller 2. The controller 2 receives the inclination angle of the aerial work platform transmitted by the inclination sensor 1, and determines whether the inclination angle of the aerial work platform exceeds the set angle; when the inclination angle of the aerial work platform does not exceed the set angle, the processing unit of the sensor controls the closure of the contacts of the second relay module by controlling the coil of the second relay module to be energized, and the controller 2 controls the coil 31 of the locking valve to be energized according to the contact closure signal of the second relay module, and the pressure oil provided by the hydraulic pump 7 enters the leveling valve 4 through the locking valve 3. At the same time, the controller 2 controls the extension and retraction of the leveling cylinder 5 in the leveling mechanism by controlling the coil 41 / 42 of the leveling valve to be energized, thereby realizing the leveling action of the aerial work platform. When the tilt angle of the aerial work platform exceeds the set angle, the processing unit of the sensor controls the disconnection of the contacts of the second relay module by controlling the de-energization of the coil of the second relay module. The controller 2 controls the de-energization of the coil 31 of the locking valve according to the contact disconnection signal of the second relay module. The pressure oil provided by the hydraulic pump 7 flows directly back to the hydraulic oil tank 6 through the locking valve 3, and the pressure of the hydraulic pipeline is zero. At this time, even if the leveling valve 4 cannot be closed or closed in time, even if the leveling valve 4 is activated, since there is no pressure in the hydraulic pipeline, the leveling cylinder 5 will not extend or retract, so that the aerial work platform is locked in the current position, avoiding the overturning problem caused by the continuous increase in the tilt angle of the aerial work platform.

[0041] In the embodiment of the utility model, the second relay module includes two relays connected in series to achieve redundancy and have higher reliability.

[0042] The utility model adds a locking valve 3. When the aerial work platform works normally (i.e. the tilt angle of the aerial work platform does not exceed the set angle), the locking valve 3 is energized and can perform normal leveling action. The controller 2 controls the coil 41 / 42 of the leveling valve to be energized, and the pressure oil provided by the hydraulic pump 7 can enter the leveling valve 4, and the leveling action of the aerial work platform is realized by controlling the extension and contraction of the leveling cylinder 5. When the tilt angle of the aerial work platform exceeds the set angle due to various reasons, the locking valve 3 loses power. Even if the control logic has a bug or the coil 41 / 42 of the leveling valve is short-circuited with the power supply or the leveling valve 4 is stuck, the pressure oil directly flows back to the hydraulic oil tank 6, and the leveling cylinder 5 stops moving due to lack of power. The leveling action will be locked, realizing the tilt protection function of the aerial work platform. At the same time, the controller 2 makes an alarm prompt and stops the current boom action, limiting the boom to operate only in the direction of the aerial work platform tending to be horizontal, and other actions that increase the tilt angle will be prohibited from output.

[0043] The above disclosure is only a specific implementation method of the utility model, but the protection scope of the utility model is not limited thereto. Any technician familiar with the technical field can easily think of changes or modifications within the technical scope disclosed in the utility model, which should be included in the protection scope of the utility model.

Claims

1. A hydraulic leveling device for an aerial work platform, comprising a sensor for detecting the tilt angle of the aerial work platform, a controller, a leveling mechanism and a hydraulic oil tank; the sensor is communicatively connected to the controller, the hydraulic oil tank is connected to the leveling valve of the leveling mechanism through a hydraulic pump, and the coil of the leveling valve is connected to the output end of the controller; characterized in that: The hydraulic leveling device also includes a locking valve; The locking valve is arranged between the hydraulic pump and the leveling valve, and the locking valve is also connected to the hydraulic oil tank. The gain and loss of electricity of the coil of the locking valve is controlled by the controller or the sensor.

2. The hydraulic leveling device for an aerial work platform according to claim 1, characterized in that: The locking valve is a switch valve or a two-position two-way solenoid valve.

3. The hydraulic leveling device for an aerial work platform according to claim 1, characterized in that: The controller is a PLC controller.

4. The hydraulic leveling device for an aerial work platform according to any one of claims 1 to 3, characterized in that: The gain and loss of power of the coil of the locking valve is controlled by the sensor through a first relay module, the contacts of the first relay module are connected in series with the coil of the locking valve, and the gain and loss of power of the coil of the first relay module is controlled by a processing unit of the sensor.

5. The hydraulic leveling device for an aerial work platform according to claim 4, characterized in that: The first relay module includes two relays connected in series.

6. The hydraulic leveling device for an aerial work platform according to any one of claims 1 to 3, characterized in that: When the gain and loss of power of the coil of the locking valve is controlled by the controller, the input end of the controller is also connected to the contact of the second relay module, and the gain and loss of power of the coil of the second relay module is controlled by the processing unit of the sensor.

7. The hydraulic leveling device for an aerial work platform according to claim 6, characterized in that: The second relay module includes two relays connected in series.

8. The hydraulic leveling device for an aerial work platform according to any one of claims 1 to 3, characterized in that: The sensor is communicatively connected with the controller via a CAN bus.

9. An aerial work platform, characterized in that: The platform comprises the hydraulic leveling device according to any one of claims 1 to 8.

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