Chassis floating control system and method for aerial work platform

Abstract

The invention discloses an aerial work platform chassis floating control system and method, and the system comprises a hydraulic oil supply valve group, an oil inlet control valve, an energy accumulator, an oil pressure control oil supply valve group, a detection assembly, a floating oil cylinder oil supply valve group, and a three-way flow valve group. The energy accumulator is connected with an oil outlet of the oil inlet control valve, the oil pressure control oil supply valve set is arranged between the energy accumulator and the oil inlet control valve, the detection assemblies are arranged on an oil outlet way of the energy accumulator and an oil outlet way of the oil pressure control oil supply valve set respectively, and an oil inlet of the floating oil cylinder oil supply valve set is connected with an oil outlet of the oil pressure control oil supply valve set. An oil inlet of the three-way flow valve bank is connected with an oil outlet of the hydraulic oil supply valve bank, and a control end of the three-way flow valve bank is connected with a pilot oil way of the oil pressure control oil supply valve bank or a pilot oil way of the main valve. The use frequency of the hydraulic pump is effectively reduced, invalid operation time of the hydraulic pump is avoided, the service life of the hydraulic pump is prolonged, oil can be supplied to the floating oil cylinder preferentially, and stable operation of the floating oil cylinder is ensured.

Description

Technical Field

[0001] The present invention belongs to the technical field of chassis floating control, and in particular relates to a chassis floating control system and method for an aerial work platform. Background Art

[0002] To ensure a level chassis, self-propelled aerial work platforms typically utilize a floating cylinder, floating control valve, and hydraulic pump control system. The main pump operates and remains on standby whenever the vehicle is in motion. When uneven ground triggers the floating cylinder to activate, the pump promptly supplies pressurized oil, ensuring the proper function of the floating function. However, this control system leaves the pump in an inactive state even when the floating cylinder is not in need of oil. This inactive operation accounts for approximately 70% of the total operating time, leaving the hydraulic pump active only approximately 30%. Given a given vehicle's range, this significantly reduces operating time, wastes energy, and shortens the life of the pump and motor. Summary of the Invention

[0003] In order to at least partially solve the technical problems existing in the above-mentioned prior art, the present invention provides a chassis floating control system and method for an aerial work platform.

[0004] The floating control system for the aerial work platform chassis of the present invention includes a hydraulic oil supply valve group, an oil inlet control valve, an accumulator, an oil pressure control oil supply valve group, a detection component, a floating cylinder oil supply valve group and a three-way flow valve group. The oil inlet of the oil inlet control valve is connected to the oil circuit of the oil outlet of the hydraulic oil supply valve group, which is used to control the hydraulic oil supply valve group to supply oil to the floating cylinder or the main valve. The accumulator is connected to the oil circuit of the oil inlet control valve outlet, which is used to store high-pressure oil. The oil pressure control oil supply valve group is arranged between the accumulator and the oil circuit of the oil inlet control valve. It is used to switch the oil supply mode of the floating cylinder oil supply valve group according to the change of the accumulator oil pressure. The detection components are respectively arranged on the accumulator oil outlet oil circuit and the oil pressure control oil supply valve group oil outlet oil circuit, and are used to detect the oil circuit pressure and provide control information to the controller. The oil inlet of the floating cylinder oil supply valve group is connected to the oil circuit of the oil pressure control oil supply valve group outlet, the oil inlet of the three-way flow valve group is connected to the oil circuit of the hydraulic oil supply valve group outlet, and the control end of the three-way flow valve group is connected to the pilot oil circuit of the oil pressure control oil supply valve group or the pilot oil circuit of the main valve, wherein:

[0005] The oil pressure control oil supply valve group includes a first valve, a second valve, a third valve, a damper, a first one-way valve, a solenoid valve, a first shuttle valve and a second shuttle valve. The oil inlet of the second valve is connected to the oil circuit of the oil outlet of the first valve, the oil inlet of the third valve is connected to the oil circuit of the oil outlet of the pilot oil circuit of the second valve, and the oil outlet of the third valve is connected to the oil circuit of the control end of the second valve. The damper is arranged on the oil circuit between the oil outlet of the third valve and the control end of the second valve, the oil inlet of the first one-way valve is connected to the oil circuit of the oil outlet of the second valve, and the oil outlet of the first one-way valve is connected to the oil circuit of the oil outlet of the second valve. The oil outlet is connected to the accumulator oil circuit, the solenoid valve oil inlet is respectively connected to the first one-way valve oil outlet and the accumulator oil circuit, the first oil inlet of the first shuttle valve is connected to the solenoid valve oil outlet oil circuit, the second oil inlet of the first shuttle valve is connected to the oil inlet control valve outlet oil circuit, the first shuttle valve oil outlet is connected to the floating cylinder oil supply valve group oil inlet oil circuit, the two oil inlets of the second shuttle valve are respectively connected to the floating cylinder oil supply valve group outlet oil circuit, and the second shuttle valve oil outlet is connected to the first valve control end.

[0006] Furthermore, in the above-mentioned chassis floating control system for aerial work platforms, the hydraulic oil supply valve group includes a hydraulic pump, a relief valve and a second one-way valve, the hydraulic pump oil inlet is connected to the oil tank, the hydraulic pump oil outlet is respectively connected to the relief valve oil inlet and the second one-way valve oil inlet oil circuit, and the relief valve overflow port is connected to the oil tank.

[0007] Furthermore, in the above-mentioned chassis floating control system for aerial work platforms, the detection component includes a first pressure sensor and a second pressure sensor, the first pressure sensor is connected to the oil outlet of the accumulator, and the second pressure sensor is connected to the oil outlet of the third valve.

[0008] Furthermore, in the above-mentioned chassis floating control system for aerial work platforms, the three-way flow valve group includes a three-way flow valve and a third shuttle valve, the first oil inlet of the third shuttle valve is connected to the oil outlet of the third valve, the second oil inlet of the third shuttle valve is connected to the pilot oil circuit of the main valve, and the oil outlet of the third shuttle valve is connected to the control end of the three-way flow valve.

[0009] Furthermore, in the above-mentioned floating control system for the aerial work platform chassis, the floating cylinder oil supply valve group includes a pressure reducing valve, a constant flow valve, a floating multi-way valve and two balancing valves. The oil inlet of the pressure reducing valve is connected to the oil circuit of the first shuttle valve oil outlet, the oil inlet of the constant flow valve is connected to the oil circuit of the pressure reducing valve oil outlet, the oil inlet of the floating multi-way valve is connected to the oil circuit of the constant flow valve oil outlet, and the two oil outlets of the floating multi-way valve are respectively connected to the floating cylinder oil circuit through the two balancing valves.

[0010] Furthermore, in the above-mentioned floating control system for the aerial work platform chassis, one of the oil outlet oil circuits of the floating multi-way valve is connected to the first oil inlet oil circuit of the second shuttle valve, and the other oil outlet oil circuit of the floating multi-way valve is connected to the second oil inlet oil circuit of the second shuttle valve.

[0011] Furthermore, in the above-mentioned floating control system for the aerial work platform chassis, the set pressure of the third valve is the maximum filling pressure of the accumulator, and the maximum filling pressure of the accumulator is less than the set pressure of the relief valve.

[0012] Furthermore, in the above-mentioned floating control system for the aerial work platform chassis, the set pressure of the second valve is greater than the maximum working pressure of the floating cylinder.

[0013] In addition, in another aspect of the present invention, a method for controlling the floating of an aerial work platform chassis implemented by using the above-mentioned aerial work platform chassis floating control system is provided, wherein the method for controlling the floating of an aerial work platform chassis comprises:

[0014] When the main valve and accumulator are not working, the third shuttle valve does not detect the feedback pressure. At this time, the hydraulic oil of the hydraulic oil supply valve group returns to the oil tank through the three-way flow valve. When the main valve and accumulator are working, the third shuttle valve controls the highest value of the main valve load pressure and the accumulator feedback pressure to the control end of the three-way flow valve, so that the three-way flow valve is cut off from the oil tank circuit.

[0015] When the accumulator is charged, the pressure is first collected through the detection component and uploaded to the controller. When the controller reads that the pressure of the first pressure sensor is lower than the set pressure of the second valve, the controller controls the hydraulic pump to work, and the accumulator feedback pressure acts on the control end of the three-way flow valve through the third shuttle valve, and the three-way flow valve is cut off. At this time, the hydraulic oil passes through the first valve, the second valve and the first check valve in sequence through the oil inlet control valve to charge the accumulator. When the accumulator pressure rises to be higher than the set pressure of the third valve, the third valve is switched. After the third valve is switched, the oil circuit of the second valve control end is connected to the return oil circuit. As the control pressure decreases, the second valve will be switched under the action of the accumulator pressure. After the switch, the accumulator oil is locked by the oil circuit, and the accumulator enters the pressure maintaining state. When the second pressure sensor detects that the pressure of the control oil circuit drops below the pressure value set by the program, the controller controls the hydraulic pump to stop, completing the charging of the accumulator.

[0016] When supplying oil to the floating cylinder, if the accumulator pressure is greater than the set pressure of the second valve, the solenoid valve is energized, and the accumulator pressure oil enters the floating multi-way valve through the solenoid valve, the first shuttle valve, the pressure reducing valve and the constant flow valve in sequence, and is distributed by the balancing valve to supply oil to the floating cylinder;

[0017] When the vehicle is in a moving state and encounters an uneven road surface, and the pressure of the accumulator used as a power source decreases, the controller reads a pressure less than the set pressure of the second valve through the first pressure sensor, and the controller controls the solenoid valve to switch to close the accumulator and supply oil to the floating cylinder. At this time, the hydraulic oil enters the first shuttle valve through the oil inlet control valve, and the hydraulic oil passes through the pressure reducing valve, the constant flow valve and the floating multi-way valve in sequence through the oil outlet of the first shuttle valve, and enters the second shuttle valve through one of the outlets of the floating multi-way valve, and enters the first valve control end through the oil outlet of the second shuttle valve to control the first valve to switch, thereby cutting off the oil supply circuit to the accumulator. At this time, the oil is distributed by the balancing valve and supplied to the floating cylinder.

[0018] The chassis floating control system and method for an aerial work platform of the present invention have the following advantages and beneficial effects:

[0019] The accumulator is automatically supplied with oil through the hydraulic oil supply valve group and the oil pressure control oil supply valve group, so that the accumulator serves as a power source to provide pressurized oil for the floating cylinder, thereby effectively reducing the frequency of use of the hydraulic oil supply valve group, thereby avoiding the ineffective operation time and energy loss of the hydraulic oil supply valve group, and extending the effective service life of the pump and motor. At the same time, when the accumulator and the floating cylinder require oil at the same time through the oil pressure control oil supply valve group, the system can give priority to supplying oil to the floating cylinder, effectively ensuring that the floating cylinder supply valve group can stably supply oil to the floating cylinder. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for the embodiments or the description of the prior art. Obviously, the drawings described below are only used to further understand the embodiments of the present invention and constitute part of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative work. In the drawings:

[0021] Figure 1 This is the hydraulic principle diagram of the chassis floating control system for aerial work platforms.

[0022] Description of reference numerals:

[0023] 1: Hydraulic oil supply valve group, 11: Hydraulic pump, 12: Overflow valve, 13: Second one-way valve;

[0024] 2: Oil inlet control valve; 3: Accumulator;

[0025] 4: Oil pressure control oil supply valve group, 41: First valve, 42: Second valve, 43: Third valve, 44: Damping, 45: First check valve, 46: Solenoid valve, 47: First shuttle valve, 48: Second shuttle valve;

[0026] 5: detection component, 51: first pressure sensor, 52: second pressure sensor;

[0027] 6: floating cylinder oil supply valve group, 61: pressure reducing valve, 62: constant flow valve, 63: floating multi-way valve, 64: balancing valve;

[0028] 7: Three-way flow valve group, 71: Three-way flow valve, 72: Third shuttle valve. DETAILED DESCRIPTION

[0029] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below in conjunction with specific embodiments of the present invention and corresponding drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0030] like Figure 1 As shown, the floating control system for the chassis of the aerial work platform of the present invention includes a hydraulic oil supply valve group 1, an oil inlet control valve 2, an accumulator 3, an oil pressure control oil supply valve group 4, a detection component 5, a floating cylinder oil supply valve group 6 and a three-way flow valve group 7. The oil inlet of the oil inlet control valve 2 is connected to the oil outlet oil circuit of the hydraulic oil supply valve group 1, which is used to control the hydraulic oil supply valve group 1 to supply oil to the floating cylinder or the main valve. The accumulator 3 is connected to the oil outlet oil circuit of the oil inlet control valve 2 for storing high-pressure oil. The oil pressure control oil supply valve group 4 is arranged between the accumulator 3 and the oil inlet control valve The oil circuit of the valve 2 is used to switch the oil supply mode of the floating cylinder oil supply valve group 6 according to the change of the oil pressure of the accumulator 3. The detection component 5 is respectively arranged on the oil outlet oil circuit of the accumulator 3 and the oil outlet oil circuit of the oil pressure control oil supply valve group 4, and is used to detect the oil circuit pressure and provide control information to the controller. The oil inlet of the floating cylinder oil supply valve group 6 is connected to the oil outlet oil circuit of the oil pressure control oil supply valve group 4, the oil inlet of the three-way flow valve group 7 is connected to the oil outlet oil circuit of the hydraulic oil supply valve group 1, and the control end of the three-way flow valve group 7 is connected to the pilot oil circuit of the oil pressure control oil supply valve group 4 or the pilot oil circuit of the main valve, wherein:

[0031] The oil pressure control oil supply valve group 4 includes a first valve 41, a second valve 42, a third valve 43, a damper 44, a first one-way valve 45, a solenoid valve 46, a first shuttle valve 47 and a second shuttle valve 48. The oil inlet of the second valve 42 is connected to the oil outlet of the first valve 41, the oil inlet of the third valve 43 is connected to the oil outlet of the pilot oil circuit of the second valve 42, the oil outlet of the third valve 43 is connected to the oil circuit of the control end of the second valve 42, the damper 44 is arranged on the oil circuit between the oil outlet of the third valve 43 and the control end of the second valve 42, the oil inlet of the first one-way valve 45 is connected to the oil outlet of the second valve 42 The oil outlet of the first one-way valve 45 is connected to the oil circuit of the accumulator 3, the oil inlet of the solenoid valve 46 is respectively connected to the oil outlet of the first one-way valve 45 and the oil circuit of the accumulator 3, the first oil inlet of the first shuttle valve 47 is connected to the oil circuit of the oil outlet of the solenoid valve 46, the second oil inlet of the first shuttle valve 47 is connected to the oil circuit of the oil outlet of the oil inlet control valve 2, the oil outlet of the first shuttle valve 47 is connected to the oil inlet oil circuit of the floating cylinder oil supply valve group 6, the two oil inlets of the second shuttle valve 48 are respectively connected to the oil outlet oil circuit of the floating cylinder oil supply valve group 6, and the oil outlet of the second shuttle valve 48 is connected to the control end of the first valve 41.

[0032] Furthermore, in the above-mentioned chassis floating control system for aerial work platforms, the hydraulic oil supply valve group 1 includes a hydraulic pump 11, a relief valve 12 and a second one-way valve 13. The oil inlet of the hydraulic pump 11 is connected to the oil tank, and the oil outlet of the hydraulic pump 11 is respectively connected to the oil inlet of the relief valve 12 and the oil inlet of the second one-way valve 13, and the overflow port of the relief valve 12 is connected to the oil tank.

[0033] Furthermore, in the above-mentioned chassis floating control system for aerial work platforms, the detection component 5 includes a first pressure sensor 51 and a second pressure sensor 52 , the first pressure sensor 51 is connected to the oil outlet of the accumulator 3 , and the second pressure sensor 52 is connected to the oil outlet of the third valve 43 .

[0034] Furthermore, in the above-mentioned floating control system for the aerial work platform chassis, the three-way flow valve group 7 includes a three-way flow valve 71 and a third shuttle valve 72, the first oil inlet of the third shuttle valve 72 is connected to the oil outlet of the third valve 43, the second oil inlet of the third shuttle valve 72 is connected to the pilot oil circuit of the main valve, and the oil outlet of the third shuttle valve 72 is connected to the control end of the three-way flow valve 71.

[0035] Furthermore, in the above-mentioned floating control system for the aerial work platform chassis, the floating cylinder oil supply valve group 6 includes a pressure reducing valve 61, a constant flow valve 62, a floating multi-way valve 63 and two balancing valves 64. The oil inlet of the pressure reducing valve 61 is connected to the oil circuit of the oil outlet of the first shuttle valve 47, the oil inlet of the constant flow valve 62 is connected to the oil circuit of the oil outlet of the pressure reducing valve 61, the oil inlet of the floating multi-way valve 63 is connected to the oil circuit of the oil outlet of the constant flow valve 62, and the two oil outlets of the floating multi-way valve 63 are respectively connected to the floating cylinder oil circuit through two balancing valves 64.

[0036] Furthermore, in the above-mentioned floating control system for the aerial work platform chassis, one of the oil outlet oil circuits of the floating multi-way valve 63 is connected to the first oil inlet oil circuit of the second shuttle valve 48, and the other oil outlet oil circuit of the floating multi-way valve 63 is connected to the second oil inlet oil circuit of the second shuttle valve 48.

[0037] Furthermore, in the above-mentioned floating control system for the aerial work platform chassis, the set pressure of the third valve 43 is the maximum filling pressure of the accumulator 3, and the maximum filling pressure of the accumulator 3 is less than the set pressure of the relief valve 12.

[0038] Furthermore, in the above-mentioned floating control system for the aerial work platform chassis, the set pressure of the second valve 42 is greater than the maximum working pressure of the floating cylinder.

[0039] Specifically, the set pressure P1 of the third valve 43 is the upper limit pressure of the accumulator 3, which is slightly lower than the set pressure of the relief valve 12. The set pressure P2 of the second valve 42 is the lower limit pressure of the accumulator 3, which is higher than the maximum pressure requirement when the chassis floats normally. The first pressure sensor 51 and the second pressure sensor 52 upload the collected pressure to the controller. The high pressure value of the actuator load pressure controlled by the third shuttle valve 72 and the feedback pressure of the accumulator 3 acts on the spring chamber of the three-way flow valve 71, ensuring that the oil can be supplied normally regardless of other actions controlled by the main valve or when the chassis floats, while also having a low-pressure standby function. When the controller reads that the pressure of the first pressure sensor 51 is lower than the set pressure P2 of the second valve 42 (that is, the pressure of the accumulator 3 is lower than the lower limit pressure), the controller will control the hydraulic pump 11 to start, and the three-way flow valve 71 is in the left position to cut off the oil circuit under the combined action of the outlet pressure, feedback pressure and spring force. The oil inlet control valve 2 is in the lower position under the action of the spring force, the first valve 41 is in the upper position under the action of the spring force, the third valve 43 is in the upper position under the action of the spring force, the second valve 42 is in the lower position under the combined action of the spring force and the control pressure, and the solenoid valve 46 is in the lower position under the action of the spring force. The pressure of the accumulator 3 is transmitted to the three-way flow valve 71 through the third valve 43 and the third shuttle valve 72, and the three-way flow valve 71 remains in the left position to cut off. At this time, the hydraulic pump 11 charges the accumulator 3 through the second one-way valve 13, the oil inlet control valve 2, the first valve 41, the second valve 42 and the first one-way valve 45. When the accumulator 3 pressure rises above the set pressure of the third valve 43, the third valve 43 switches to the down position. Pressure in the control oil circuit between the third valve 43 and the three-way flow valve 71 is released to port T through the damper 44 in the lower position of the third valve 43, reducing the pressure to the return oil pressure. The second valve 42, losing its upper control pressure, also switches to the down position. When the second pressure sensor 52 detects that the pressure has dropped to the programmed set value, the controller issues a control signal to stop the hydraulic pump 11, completing the filling process. During vehicle travel when the accumulator 3 pressure exceeds the lower pressure limit, the solenoid valve 46 is energized and switches to the up position. Accumulator 3 pressure oil flows through the solenoid valve 46, the first shuttle valve 47, the pressure reducing valve 61, and the constant flow valve 62 to port P of the float multi-way valve 63. This chassis floating mechanism is consistent with current mainstream floating mechanisms. When the vehicle encounters uneven road conditions, the swinging of the axle opens the float multi-way valve 63, allowing pressure oil to enter the float cylinder to ensure proper floating function. When the accumulator 3 is at its upper pressure limit, the pressure relief valve 61 minimizes pressure surges, and the constant flow valve 62 regulates the speed of the floating cylinder. When the accumulator 3 pressure is above the lower pressure limit, the solenoid valve 46 remains energized, supplying pressurized oil to the floating cylinder. When the accumulator 3 is used as a power source, the pressure decreases. When the controller reads the pressure at the first pressure sensor 51 and it is lower than the set pressure P2 of the second valve 42, the controller de-energizes the solenoid valve 46 and switches it to the lower position. The controller then activates the hydraulic pump 11 to charge the accumulator 3.If the vehicle is moving at this time and encounters an uneven road surface, the floating multi-way valve 63 is opened. At this time, no matter whether the oil is discharged from port A or port B of the floating multi-way valve 63, the load pressure will be transmitted to the lower end of the first valve 41 through the selection of the second shuttle valve 48. The first valve 41 switches to the lower position. At this time, the oil circuit leading to the accumulator 3 is cut off, and the pressure oil of the oil inlet control valve 2 flows through the first shuttle valve 47 into the pressure reducing valve 61 and flows to the floating cylinder to ensure the normal operation of the floating function. After the floating multi-way valve 63 is closed, the pressure at the lower end of the first valve 41 gradually decreases, and the first valve 41 will switch to the upper position under the action of the spring force, and the oil circuit of the hydraulic pump 11 to the accumulator 3 is reconnected to continue to charge the accumulator 3.

[0040] In addition, in another aspect of the present invention, a chassis floating control method for an aerial work platform is provided, which is implemented using the above chassis floating control system for an aerial work platform. The chassis floating control method for an aerial work platform includes:

[0041] When the main valve and accumulator 3 are not working, the third shuttle valve 72 does not detect the feedback pressure. At this time, the hydraulic oil in the hydraulic oil supply valve group 1 returns to the oil tank through the three-way flow valve 71. When the main valve and accumulator 3 are working, the third shuttle valve 72 applies the highest value of the controlled main valve load pressure and the accumulator 3 feedback pressure to the control end of the three-way flow valve 71, so that the three-way flow valve 71 is cut off from the oil tank circuit.

[0042] When the accumulator 3 is charged, the pressure is first collected by the detection component 5 and uploaded to the controller. When the controller reads that the pressure of the first pressure sensor 51 is lower than the set pressure of the second valve 42, the controller controls the hydraulic pump 11 to work, and the feedback pressure of the accumulator 3 acts on the control end of the three-way flow valve 71 through the third shuttle valve 72. The three-way flow valve 71 is cut off. At this time, the hydraulic oil passes through the first valve 41, the second valve 42 and the first check valve 45 in sequence through the oil inlet control valve 2 to charge the accumulator 3. When the pressure of the accumulator 3 rises to greater than the set pressure of the third valve 43, the third valve 43 switches position. After the switching of the third valve 43, the oil circuit of the control end of the second valve 42 is connected to the return oil circuit. As the control pressure decreases, the second valve 42 will switch position under the action of the pressure of the accumulator 3. After the switching, the oil in the accumulator 3 is locked by the oil circuit, and the accumulator 3 enters a pressure-maintaining state. When the second pressure sensor 52 detects that the pressure of the control oil circuit drops below the pressure value set by the program, the controller controls the hydraulic pump 11 to stop, completing the charging of the accumulator 3.

[0043] When the floating cylinder is supplied with oil, if the pressure of the accumulator 3 is greater than the set pressure of the second valve 42, the solenoid valve 46 is energized, and the pressure oil of the accumulator 3 enters the floating multi-way valve 63 through the solenoid valve 46, the first shuttle valve 47, the pressure reducing valve 61 and the constant flow valve 62 in sequence, and is distributed by the balancing valve 64 to supply the floating cylinder with oil.

[0044] When the vehicle is in a moving state and encounters an uneven road surface, and the pressure of the accumulator 3 used as a power source decreases, the controller reads a pressure less than the set pressure of the second valve 42 through the first pressure sensor 51, and the controller controls the solenoid valve 46 to switch to close the accumulator 3 and supply oil to the floating cylinder. At this time, the hydraulic oil enters the first shuttle valve 47 through the oil inlet control valve 2, and the hydraulic oil passes through the oil outlet of the first shuttle valve 47 in sequence through the pressure reducing valve 61, the constant flow valve 62 and the floating multi-way valve 63, and enters the second shuttle valve 48 through one of the outlets of the floating multi-way valve 63, and enters the first valve 41 through the oil outlet of the second shuttle valve 48. The control end controls the first valve 41 to switch, thereby cutting off the oil supply to the accumulator 3. At this time, the oil is distributed through the balance valve 64 and supplies oil to the floating cylinder.

[0045] To sum up, compared with the existing technology, the floating control system and method for the aerial work platform chassis of the present invention has the following advantages and beneficial effects: automatic oil supply to the accumulator is achieved through the hydraulic oil supply valve group and the oil pressure control oil supply valve group, so that the accumulator serves as a power source to provide pressurized oil for the floating cylinder, thereby effectively reducing the frequency of use of the hydraulic oil supply valve group, thereby avoiding the ineffective operation time and energy loss of the hydraulic oil supply valve group, and extending the effective service life of the pump and motor. At the same time, when the accumulator and the floating cylinder require oil at the same time through the oil pressure control oil supply valve group, the system can give priority to supplying oil to the floating cylinder, effectively ensuring that the floating cylinder supply valve group stably supplies oil to the floating cylinder.

[0046] It should be noted that, in this document, unless otherwise expressly specified or limited, the term "connected" or its synonyms should be interpreted broadly. For example, "connected" can mean a fixed or removable connection; a mechanical or electrical connection; a direct connection or an indirect connection through an intermediate medium; or the internal communication between two elements or the interaction between two elements. A person of ordinary skill in the art will understand the specific meanings of these terms in the present invention based on the specific circumstances. Furthermore, expressions such as "first" and "second" are used solely to distinguish one entity or operation from another and do not necessarily require or imply any actual relationship or order between these entities or operations. Furthermore, the terms "comprise," "include," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, article, or apparatus comprising a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus. Furthermore, the terms "front," "rear," "left," "right," "upper," and "lower" herein are used with reference to the positions shown in the accompanying drawings.

[0047] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A floating control system for the chassis of an aerial work platform, arranged between the floating oil cylinder, the main valve and the oil tank, characterized in that: The floating control system for the aerial work platform chassis includes a hydraulic oil supply valve group, an oil inlet control valve, an accumulator, an oil pressure control oil supply valve group, a detection component, a floating cylinder oil supply valve group and a three-way flow valve group. The oil inlet of the oil inlet control valve is connected to the oil circuit of the oil outlet of the hydraulic oil supply valve group, which is used to control the hydraulic oil supply valve group to supply oil to the floating cylinder or the main valve. The accumulator is connected to the oil circuit of the oil inlet control valve outlet for storing high-pressure oil. The oil pressure control oil supply valve group is arranged between the accumulator and the oil circuit of the oil inlet control valve. In order to switch the oil supply mode of the floating cylinder oil supply valve group according to the change of the accumulator oil pressure, the detection components are respectively arranged on the accumulator oil outlet oil circuit and the oil pressure control oil supply valve group oil outlet oil circuit, and are used to detect the oil circuit pressure and provide control information to the controller. The oil inlet of the floating cylinder oil supply valve group is connected to the oil circuit of the oil pressure control oil supply valve group outlet, the oil inlet of the three-way flow valve group is connected to the oil circuit of the hydraulic oil supply valve group outlet, and the control end of the three-way flow valve group is connected to the pilot oil circuit of the oil pressure control oil supply valve group or the pilot oil circuit of the main valve, wherein: The oil pressure control oil supply valve group includes a first valve, a second valve, a third valve, a damper, a first one-way valve, a solenoid valve, a first shuttle valve and a second shuttle valve. The oil inlet of the second valve is connected to the oil circuit of the oil outlet of the first valve, the oil inlet of the third valve is connected to the oil circuit of the oil outlet of the pilot oil circuit of the second valve, and the oil outlet of the third valve is connected to the oil circuit of the control end of the second valve. The damper is arranged on the oil circuit between the oil outlet of the third valve and the control end of the second valve, the oil inlet of the first one-way valve is connected to the oil circuit of the oil outlet of the second valve, and the oil outlet of the first one-way valve is connected to the oil circuit of the oil outlet of the second valve. The oil outlet is connected to the accumulator oil circuit, the solenoid valve oil inlet is respectively connected to the first one-way valve oil outlet and the accumulator oil circuit, the first oil inlet of the first shuttle valve is connected to the solenoid valve oil outlet oil circuit, the second oil inlet of the first shuttle valve is connected to the oil inlet control valve outlet oil circuit, the first shuttle valve oil outlet is connected to the floating cylinder oil supply valve group oil inlet oil circuit, the two oil inlets of the second shuttle valve are respectively connected to the floating cylinder oil supply valve group outlet oil circuit, and the second shuttle valve oil outlet is connected to the first valve control end.

2. The chassis floating control system for aerial work platforms according to claim 1 is characterized in that: The hydraulic oil supply valve group includes a hydraulic pump, a relief valve and a second one-way valve. The hydraulic pump oil inlet is connected to the oil tank, and the hydraulic pump oil outlet is respectively connected to the oil circuits of the relief valve oil inlet and the second one-way valve oil inlet, and the relief valve overflow port is connected to the oil tank.

3. The chassis floating control system for aerial work platforms according to claim 1, characterized in that: The detection assembly includes a first pressure sensor and a second pressure sensor. The first pressure sensor is connected to the oil outlet of the accumulator, and the second pressure sensor is connected to the oil outlet of the third valve.

4. The chassis floating control system for aerial work platforms according to claim 2, characterized in that: The three-way flow valve group includes a three-way flow valve and a third shuttle valve, the first oil inlet of the third shuttle valve is connected to the oil outlet of the third valve, the second oil inlet of the third shuttle valve is connected to the pilot oil circuit of the main valve, and the oil outlet of the third shuttle valve is connected to the control end of the three-way flow valve.

5. The chassis floating control system for aerial work platforms according to claim 1, characterized in that: The floating cylinder oil supply valve group includes a pressure reducing valve, a constant flow valve, a floating multi-way valve and two balancing valves. The oil inlet of the pressure reducing valve is connected to the oil circuit of the first shuttle valve oil outlet, the oil inlet of the constant flow valve is connected to the oil circuit of the pressure reducing valve oil outlet, the oil inlet of the floating multi-way valve is connected to the oil circuit of the constant flow valve oil outlet, and the two oil outlets of the floating multi-way valve are respectively connected to the floating cylinder oil circuit through the two balancing valves.

6. The chassis floating control system for aerial work platforms according to claim 5, characterized in that: One oil outlet oil circuit of the floating multi-way valve is connected to the first oil inlet oil circuit of the second shuttle valve, and the other oil outlet oil circuit of the floating multi-way valve is connected to the second oil inlet oil circuit of the second shuttle valve.

7. The chassis floating control system for aerial work platforms according to claim 2, characterized in that: The third valve setting pressure is the maximum filling pressure of the accumulator, and the maximum filling pressure of the accumulator is less than the relief valve setting pressure.

8. The chassis floating control system for aerial work platforms according to claim 7, characterized in that: The setting pressure of the second valve is greater than the maximum working pressure of the floating oil cylinder.

9. A control method implemented by using the chassis floating control system for an aerial work platform according to any one of claims 1 to 8, characterized in that: The floating control method for the chassis of an aerial work platform includes: When the main valve and accumulator are not working, the third shuttle valve does not detect the feedback pressure. At this time, the hydraulic oil of the hydraulic oil supply valve group returns to the oil tank through the three-way flow valve. When the main valve and accumulator are working, the third shuttle valve controls the highest value of the main valve load pressure and the accumulator feedback pressure to the control end of the three-way flow valve, so that the three-way flow valve is cut off from the oil tank circuit. When the accumulator is charged, the pressure is first collected through the detection component and uploaded to the controller. When the controller reads that the pressure of the first pressure sensor is lower than the set pressure of the second valve, the controller controls the hydraulic pump to work, and the accumulator feedback pressure acts on the control end of the three-way flow valve through the third shuttle valve, and the three-way flow valve is cut off. At this time, the hydraulic oil passes through the first valve, the second valve and the first check valve in sequence through the oil inlet control valve to charge the accumulator. When the accumulator pressure rises to be higher than the set pressure of the third valve, the third valve is switched. After the third valve is switched, the oil circuit of the second valve control end is connected to the return oil circuit. As the control pressure decreases, the second valve will be switched under the action of the accumulator pressure. After the switch, the accumulator oil is locked by the oil circuit, and the accumulator enters the pressure maintaining state. When the second pressure sensor detects that the pressure of the control oil circuit drops below the pressure value set by the program, the controller controls the hydraulic pump to stop, completing the charging of the accumulator. When supplying oil to the floating cylinder, if the accumulator pressure is greater than the set pressure of the second valve, the solenoid valve is energized, and the accumulator pressure oil enters the floating multi-way valve through the solenoid valve, the first shuttle valve, the pressure reducing valve and the constant flow valve in sequence, and is distributed by the balancing valve to supply oil to the floating cylinder; When the vehicle is in a moving state and encounters an uneven road surface, and the pressure of the accumulator used as a power source decreases, the controller reads a pressure less than the set pressure of the second valve through the first pressure sensor, and the controller controls the solenoid valve to switch to close the accumulator and supply oil to the floating cylinder. At this time, the hydraulic oil enters the first shuttle valve through the oil inlet control valve, and the hydraulic oil passes through the pressure reducing valve, the constant flow valve and the floating multi-way valve in sequence through the oil outlet of the first shuttle valve, and enters the second shuttle valve through one of the outlets of the floating multi-way valve, and enters the first valve control end through the oil outlet of the second shuttle valve to control the first valve to switch, thereby cutting off the oil supply circuit to the accumulator. At this time, the oil is distributed by the balancing valve and supplied to the floating cylinder.

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