Hydraulic oil temperature control system of boom type aerial work platform

Abstract

The utility model provides a hydraulic oil temperature control system for an arm support type aerial work platform, which comprises a hydraulic oil tank, a hydraulic oil conveying assembly, an arm support working hydraulic system, a platform valve and a controller ECU (electronic control unit), and an electromagnetic proportional overflow valve is mounted on an oil way between a load-sensitive pump and a main control valve group; the platform reversing valve is a three-position five-way electromagnetic valve, and a load-sensitive oil port LS3 of the platform reversing valve is connected with a load-sensitive oil port LS2 of the main control valve group; a temperature sensor is installed in the hydraulic oil tank and connected with the controller ECU through a signal wire harness. The hydraulic oil tank has the beneficial effects that small-pressure and large-flow overflow is realized by utilizing variable characteristics of the load-sensitive pump and liquid resistance formed by the overflow valve, so that the temperature of oil in the hydraulic oil tank is quickly increased, a hydraulic oil heating device is not additionally arranged independently, and the quality of hydraulic oil is not influenced; the problem that the hydraulic oil can be quickly preheated by the aerial work platform in low-temperature or extremely cold weather without increasing energy consumption and cost is solved.

Description

Technical Field

[0001] The utility model relates to a hydraulic oil temperature control system, in particular to a boom type aerial work platform hydraulic oil temperature control system, belonging to the technical field of aerial work devices. Background Art

[0002] Aerial work platforms have been used in various high-altitude work scenarios. Whether they are located in the extremely cold polar regions or in areas with high temperatures all year round, aerial work platforms can be seen everywhere. Hydraulic technology is applied to aerial work platforms as one of the main key technologies. Hydraulic oil is sensitive to temperature changes. The lower the temperature, the greater the viscosity of the hydraulic oil. If the equipment is working at this time, the high-viscosity hydraulic oil will not only flow slowly in the pipes and components, but also affect the running speed of the equipment. At the same time, it will affect the self-priming ability of the pump and damage the hydraulic pump. In order for the hydraulic system to work efficiently and normally, the hydraulic oil in a low-temperature environment needs to be preheated. At present, the commonly used hydraulic oil preheating methods are mainly direct heating of hydraulic oil and overflow heating of hydraulic oil. Although direct heating can preheat hydraulic oil, long-term use of the heating boiler will cause partial carbonization of the oil and affect the quality and service life of the oil. Overflow heating increases the temperature through the friction of the oil itself, which can make the oil heated evenly and not carbonized.

[0003] In order to overcome the shortcomings of the existing technology, make full use of the existing hydraulic components and reduce costs, this patent, based on the overflow heating technology, fully utilizes the characteristics of the load-sensitive pump, combines temperature sensors and controllers, and realizes rapid preheating of the hydraulic system to achieve the normal operating temperature conditions of the hydraulic system. Summary of the invention

[0004] Purpose of the invention: In view of the deficiencies in the prior art, the utility model provides a hydraulic oil temperature control system for a boom-type aerial work platform, which realizes a small pressure and large flow overflow by utilizing the variable characteristics of a load-sensitive pump and the fluid resistance formed by a relief valve, so that the oil in the hydraulic oil tank is quickly heated up, and a hydraulic oil heating device is no longer needed to be added separately, so that the quality of the hydraulic oil is not affected; the problem that the aerial work platform can quickly preheat the hydraulic oil in low temperature or extremely cold weather without increasing energy consumption and cost is solved.

[0005] Technical solution: A hydraulic oil temperature control system for a boom-type aerial work platform, comprising a hydraulic oil tank, a hydraulic oil delivery assembly, a boom working hydraulic system, a platform valve and a controller ECU, characterized in that: the hydraulic oil delivery assembly comprises a load-sensitive pump, an electromagnetic proportional relief valve and a main control valve group, and the controller ECU is electrically connected to the electromagnetic proportional relief valve and the electromagnets of each valve in the main control valve group respectively;

[0006] The electromagnetic proportional relief valve is installed in the oil circuit between the load sensing pump and the main control valve group;

[0007] The pressure oil port P1 of the load sensing pump is connected to the oil inlet P2 of the main control valve group through a hydraulic pipeline, and the load sensing pressure oil port LS1 of the load sensing pump is connected to the load sensing oil port LS2 of the main control valve group;

[0008] The main control valve group includes a boom control valve group and a platform control valve group, the platform control valve group includes a platform reversing valve and a one-way valve, and the platform control valve group is arranged at the tail joint of the main control valve group;

[0009] The boom control valve group is connected to the boom working hydraulic system pipeline, the platform reversing valve is connected to the platform valve pipeline, the platform reversing valve is a three-position five-way solenoid valve, and the load sensitive oil port LS3 of the platform reversing valve is connected to the load sensitive oil port LS2 of the main control valve group;

[0010] An oil return pipeline is connected between the platform valve and the oil cylinder, and the oil return ports of the electromagnetic proportional relief valve and the main control valve group are both connected to the oil return hydraulic pipeline;

[0011] A temperature sensor is installed in the hydraulic oil tank, and the temperature sensor is connected to the controller ECU through a signal harness.

[0012] The utility model sets the relief valve as an electromagnetic proportional relief valve, and adjusts the set pressure value of the electromagnetic proportional relief valve through the controller ECU control, and sets different hydraulic oil processing strategies according to the data of the temperature sensor, and realizes small pressure and large flow overflow by utilizing the variable characteristics of the load sensitive pump and the liquid resistance formed by the relief valve, so that the oil in the hydraulic oil tank is quickly heated up, and no hydraulic oil heating device is added separately, so that the quality of the hydraulic oil is not affected; and the problem that the aerial work platform can quickly preheat the hydraulic oil in low temperature or extremely cold weather without increasing energy consumption and cost is solved.

[0013] When the solenoid on the right side of the platform reversing valve is energized, the valve switches to the right position and is sealed by a one-way valve to prevent oil leakage at port B. At this time, the pressure at the pressure port P1 of the load sensing pump is connected to the pressure at the load sensing pressure port LS1 of the load sensing pump, and the pressure is fed back to the load sensing valve to achieve control. Since there is no oil flow at the valve at this time, the pressure at the pressure port P1 of the load sensing pump is equal to the load sensing pressure, so the function of the load sensing valve is shielded, and the hydraulic oil begins to overflow and heat up at a large flow rate.

[0014] The electromagnetic proportional relief valve is integrated and installed in the main control valve group, and the electromagnetic proportional relief valve is installed at the inner oil inlet near the main control valve group.

[0015] An electromagnetic proportional relief valve is arranged in the existing main control valve group and integratedly installed to facilitate inspection and maintenance, while improving the neatness and appearance of the vehicle structure.

[0016] The electromagnetic proportional relief valve is provided separately and installed at the outer oil inlet near the main control valve group. The pressure oil port P1 of the load sensing pump is connected to the oil inlet P3 of the electromagnetic proportional relief valve. The oil inlet P3 of the electromagnetic proportional relief valve is connected to the oil inlet P2 of the main control valve.

[0017] Installing the electromagnetic proportional relief valve outside the main control valve group is convenient for processing and installation. If it is installed inside the main control valve group, the structural distribution of the main control valve group needs to be readjusted and planned, which increases the production cost. The effect on the work of the hydraulic system is the same. Therefore, it is more advantageous to set up the electromagnetic proportional relief valve separately.

[0018] The platform control valve group also includes a compensation valve arranged on the oil inlet pipeline between the platform reversing valve and the arm control valve group. The return oil port of the compensation valve is connected to the return oil hydraulic pipeline. The load sensitive oil port LS4 of the compensation valve is connected to the hydraulic pipeline between the load sensitive oil port LS2 of the main control valve group and the load sensitive oil port LS3 of the platform reversing valve.

[0019] The compensation valve plays a role in the load-sensitive circuit to ensure that the movement speed of the whole machine will not be affected by the change of load when it is in action. Due to the hydraulic oil preheating stage, the right electromagnet of the platform reversing valve is energized and blocked by the one-way valve. When the oil does not flow here, the pressure of the pressure oil port P1 of the load-sensitive pump is equal to the pressure of the load-sensitive pressure oil port LS1 of the load-sensitive pump, and the system starts to perform large-flow overflow heating on the hydraulic oil; when the hydraulic oil is preheated, the priority of the whole machine action is higher than the preheating of the oil tank oil, the oil flows, and a pressure drop is generated at the compensation valve. At this time, the load-sensitive valve of the load-sensitive pump will work for the platform to work.

[0020] The load-sensitive pump includes a one-way variable pump whose oil suction port is connected to the hydraulic oil tank, and also includes a pressure cut-off valve and a load-sensitive valve. The one-way variable pump is connected to a power source through a transmission shaft. A speed sensor is provided on the power source, and the speed sensor is connected to a controller ECU through a signal harness.

[0021] By setting a speed sensor at the power source and monitoring the running time of the speed sensor through the controller ECU; the one-way variable pump adjusts different opening sizes according to the oil temperature and running time to achieve flow control.

[0022] The pressure cut-off valve mainly plays a protective role. That is, when the pressure reaches the set value, the pressure oil acts on the variable mechanism, making the pump displacement smaller, so that it protects the pump from exceeding the rated pressure and prolongs the life of the pump.

[0023] The pressure cut-off valve and the load sensing valve are both two-position three-way valves, and the load sensing oil port LS5 of the load sensing valve is connected to the load sensing oil port LS1 of the load sensing pump.

[0024] The load-sensing pump plays a role in load-sensitive control, which is an energy-saving design of the pump. In order to make the load-sensitive valve ineffective during the hydraulic oil preheating stage and to be able to adapt to the oil flow strategy of the entire machine and play a role in time after the hydraulic oil reaches the working temperature, the load-sensitive oil port LS5 of the load-sensitive valve is connected to the load-sensitive oil port LS1 of the load-sensitive pump.

[0025] In order to preheat the low-temperature hydraulic oil, the platform reversing valve is a three-position five-way reversing solenoid valve with a "Y" type mid-position function. The solenoid valve is closed in the mid-position, and the valve core can output the feedback pressure signal to the load-sensitive oil port LS4 of the compensation valve, thereby controlling the load-sensitive valve of the load-sensitive pump. The platform reversing valve is designed with electromagnets Y1 and Y2 respectively. When Y2 is energized, the platform reversing valve switches to the right position to work.

[0026] Beneficial effect: The utility model sets the relief valve as an electromagnetic proportional relief valve, and adjusts the set pressure value of the electromagnetic proportional relief valve through the controller ECU. At the same time, different hydraulic oil processing strategies are set according to the data of the temperature sensor. By utilizing the variable characteristics of the load-sensitive pump and the fluid resistance formed by the relief valve, a small pressure and large flow overflow is achieved, so that the oil in the hydraulic oil tank is quickly heated up, and there is no need to add a separate hydraulic oil heating device, which does not affect the quality of the hydraulic oil. The utility model solves the problem that the aerial work platform can quickly preheat the hydraulic oil in low temperature or extremely cold weather without increasing energy consumption and cost.

[0027] The insulation function can be realized. When the device is not in action, when the temperature sensor detects that the temperature is lower than the set temperature, the insulation function starts. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings in the following description are only embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0029] Figure 1 This is a hydraulic principle diagram of the electromagnetic proportional relief valve of the utility model integrated in the main control valve group.

[0030] Figure 2 This is a hydraulic principle diagram of the electromagnetic proportional relief valve of the utility model which is separately arranged outside the main control valve group.

[0031] Figure 3 This is the hydraulic principle diagram of the electromagnetic proportional relief valve of the utility model.

[0032] Figure 4This is the hydraulic principle diagram of the platform reversing valve of the utility model.

[0033] Figure 5 This is a schematic diagram of the signal input and output targets of the controller ECU of the utility model.

[0034] Figure 6 The utility model is a flow chart of a control method for preheating hydraulic oil. DETAILED DESCRIPTION

[0035] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions 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 in 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.

[0036] In the description of the present invention, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and 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 orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0037] In the present utility model, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0038] like Figures 1 to 5 As shown, a hydraulic oil temperature control system for a boom-type aerial work platform includes a hydraulic oil tank 1, a hydraulic oil delivery assembly, a working hydraulic system 2, a platform valve 3 and a controller ECU, characterized in that: the hydraulic oil delivery assembly includes a load-sensitive pump 4, an electromagnetic proportional relief valve 5 and a main control valve group 6, and the controller ECU is electrically connected to the electromagnetic proportional relief valve 5 and the electromagnet of each valve in the main control valve group 6 respectively;

[0039] The electromagnetic proportional relief valve 5 is installed in the oil circuit between the load sensing pump 4 and the main control valve group 6;

[0040] The pressure oil port P1 of the load sensing pump 4 is connected to the oil inlet P2 of the main control valve group 6 through a hydraulic pipeline, and the load sensing pressure oil port LS1 of the load sensing pump 4 is connected to the load sensing oil port LS2 of the main control valve group 6;

[0041] The main control valve group 6 includes a working control valve group 61 and a platform control valve group 62. The platform control valve group 62 includes a platform reversing valve 621 and a one-way valve 622. The platform control valve group 62 is arranged at the tail of the main control valve group 6.

[0042] The working control valve group 61 is connected to the working hydraulic system 2 pipeline, the platform reversing valve 621 is connected to the platform valve 3 pipeline, the platform reversing valve 621 is a three-position five-way solenoid valve, and the load sensitive oil port LS3 of the platform reversing valve 621 is connected to the load sensitive oil port LS2 of the main control valve group 6;

[0043] An oil return pipeline is connected between the platform valve 3 and the oil cylinder, and the oil return ports of the electromagnetic proportional relief valve 5 and the main control valve group 6 are both connected to the oil return hydraulic pipeline;

[0044] A temperature sensor 8 is installed in the hydraulic oil tank 1 , and the temperature sensor 8 is connected to the controller ECU through a signal harness.

[0045] The utility model sets the relief valve as an electromagnetic proportional relief valve 5, and adjusts the set pressure value of the electromagnetic proportional relief valve 5 through the controller ECU control, and sets different hydraulic oil processing strategies according to the data of the temperature sensor 8, and realizes small pressure and large flow overflow by utilizing the variable characteristics of the load sensitive pump 4 and the liquid resistance formed by the relief valve, so that the oil in the hydraulic oil tank 1 is quickly heated up, and no hydraulic oil heating device is added separately, so that the quality of the hydraulic oil is not affected; the problem that the aerial work platform can quickly preheat the hydraulic oil in low temperature or extremely cold weather without increasing energy consumption and cost is solved.

[0046] When the electromagnet on the right side of the platform reversing valve 621 is energized, the valve switches to the right position and is sealed by the one-way valve 622 to prevent oil leakage at port B. At this time, the pressure at the pressure port P1 of the load-sensing pump 4 is connected to the pressure at the load-sensing pressure port LS1 of the load-sensing pump 4, and the pressure is fed back to the load-sensing valve 43 to achieve control. Since there is no oil flow at the valve at this time, the pressure at the pressure port P1 of the load-sensing pump 4 is equal to the load-sensing pressure, so the function of the load-sensing valve 43 is shielded, and the hydraulic oil begins to overflow and heat up at a large flow rate.

[0047] like Figure 1 As shown, the electromagnetic proportional relief valve 5 is integrated in the main control valve group 6 , and the electromagnetic proportional relief valve 5 is installed near the inner oil inlet of the main control valve group 6 .

[0048] The electromagnetic proportional relief valve 5 is arranged in the existing main control valve group 6, and the integrated installation is convenient for inspection and maintenance, and at the same time improves the neatness and beauty of the vehicle structure.

[0049] like Figure 2 As shown, the electromagnetic proportional relief valve 5 is provided separately, and the electromagnetic proportional relief valve 5 is installed at the outer oil inlet near the main control valve group 6, the pressure oil port P1 of the load sensing pump 4 is connected with the oil inlet P3 of the electromagnetic proportional relief valve 5, and the oil inlet P3 of the electromagnetic proportional relief valve 5 is connected with the oil inlet P2 of the main control valve.

[0050] Installing the electromagnetic proportional relief valve 5 outside the main control valve group 6 is convenient for processing and installation. If it is installed inside the main control valve group 6, the structural distribution of the main control valve group 6 needs to be readjusted and planned, which increases the production cost. The effect on the operation of the hydraulic system is the same. Therefore, it is more advantageous to set the electromagnetic proportional relief valve 5 separately.

[0051] The platform control valve group 62 also includes a compensation valve 623 arranged on the oil inlet pipeline between the platform reversing valve 621 and the working control valve group 61, the return oil port of the compensation valve 623 is connected to the return oil hydraulic pipeline, and the load sensitive oil port LS4 of the compensation valve 623 is connected to the hydraulic pipeline between the load sensitive oil port LS2 of the main control valve group 6 and the load sensitive oil port LS3 of the platform reversing valve 621.

[0052] It plays a role in the load-sensitive circuit to ensure that the movement speed of the whole machine will not be affected by changes in the load when it moves. Due to the hydraulic oil preheating stage, the right electromagnet of the platform reversing valve 621 is energized and blocked by the one-way valve 622. When the oil does not flow here, the pressure of the pressure oil port P1 of the load-sensitive pump 4 is equal to the pressure of the load-sensitive pressure oil port LS1 of the load-sensitive pump 4, and the system starts to perform large-flow overflow heating on the hydraulic oil; when the hydraulic oil is preheated, the priority of the whole machine action is higher than the mailbox oil preheating, the oil flows, and a pressure drop is generated at the compensation valve 623. At this time, the load-sensitive valve 43 of the load-sensitive pump 4 will work for the platform to work.

[0053] The load-sensitive pump 4 includes a one-way variable pump 41 whose oil suction port is connected to the hydraulic oil tank 1, and also includes a pressure cut-off valve 42 and a load-sensitive valve 43. The one-way variable pump 41 is connected to the power source 7 through a transmission shaft. A speed sensor 71 is provided on the power source 7, and the speed sensor 71 is connected to the controller ECU through a signal harness.

[0054] By setting a speed sensor 71 on the power source 7 and monitoring the running time of the speed sensor 71 through the controller ECU; the one-way variable pump 41 adjusts different opening sizes according to the oil temperature and the running time to achieve flow control.

[0055] The pressure cut-off valve 42 mainly plays a protective role. That is, when the pressure reaches the set value, the pressure oil acts on the variable mechanism to reduce the pump displacement, thereby protecting the pump from exceeding the rated pressure and extending the life of the pump.

[0056] The pressure cut-off valve 42 and the load sensing valve 43 are both two-position three-way valves. The load sensing oil port LS4 of the load sensing valve 43 is connected to the load sensing oil port LS1 of the load sensing pump 4 .

[0057] The load-sensing pump 4 plays a load-sensitive control role, which is an energy-saving design of the pump. In order to make the load-sensing valve 43 ineffective during the hydraulic oil preheating stage and to be able to adapt to the oil flow strategy of the entire machine in time and play a role after the hydraulic oil reaches the working temperature, the load-sensing oil port LS4 of the load-sensing valve 43 is connected to the load-sensing oil port LS1 of the load-sensing pump 4.

[0058] The platform reversing valve 621 is a three-position five-way reversing solenoid valve with a "Y" type mid-position function. The solenoid valve is closed in the mid-position, and the valve core can output a feedback pressure signal to the load-sensitive oil port LS4 of the compensation valve 623, thereby controlling the load-sensitive valve 43 of the load-sensitive pump 4. The platform reversing valve 621 is designed with electromagnets Y1 and Y2 respectively. When Y2 is energized, the platform reversing valve 621 switches to the right position to work.

[0059] The hydraulic oil heating control method of this scheme is as follows:

[0060] like Figure 6 As shown, in this hydraulic system, after the engine is started, if no button of the machine is operated, the load-sensitive pump 4 will operate at low pressure and small flow. At this time, the flow generated by the load-sensitive pump 4 is only used to maintain the lubrication and leakage of the pump itself, and there is no oil output to the system. When the whole machine enable switch is operated, the controller detects the signal of the enable switch, and according to the operation action, the corresponding electromagnet is powered. At this time, since the load-sensitive pump 4LS1 end receives the control signal, the load-sensitive pump 4 starts to supply oil to the system. Regardless of whether the enable switch is operated, when the engine has a speed output and the oil tank meets the relevant temperature range, the preheating system starts automatically.

[0061] This solution is mainly aimed at preheating the hydraulic oil when the temperature is low. When the engine is in a low temperature environment, it needs to be started and preheated. At this time, the engine drives the load-sensitive pump 4 to start working. At this time, the load-sensitive pump 4 is in a low-pressure and low-flow self-lubricating state. When time passes, t 0, the load-sensing pump 4 is fully lubricated and the air in the pump housing is removed. At this time, the controller controls the electromagnet Y2 end of the platform reversing valve 621 in the main control valve to be energized, and the load-sensing pump 4 begins to receive variable signals. At the same time, the controller ECU adjusts the set pressure of the electric proportional relief valve according to the definition.p 1 ( p 0 < p 1 < p s ), at this time, the load-sensitive pump 4 starts to overflow at low pressure and large flow rate, and starts to preheat the hydraulic oil in the hydraulic oil tank 1.

[0062] Note:

[0063] p 0 — The set pressure of the load-sensitive valve 43 of the load-sensitive pump 4;

[0064] p 1 — The set pressure of the electro-hydraulic proportional relief valve;

[0065] p s — The pressure cut-off set pressure of the load-sensitive pump 4.

[0066] When after time t1, when the temperature sensor 8 of the hydraulic oil tank 1 detects that the temperature of the hydraulic oil reaches or exceeds the minimum operating temperature T1 of the load-sensitive pump 4, the controller ECU adjusts the set pressure of the electro-hydraulic proportional relief valve according to the definition p 2 ( p 1 < p 2 < p s ), at this time, the load-sensitive pump 4 starts to overflow at medium-high pressure and large flow rate, and the temperature of the hydraulic oil in the hydraulic oil tank 1 rises rapidly.

[0067] When after time t 2, when the temperature of the hydraulic oil tank 1 rises to the preset temperature range T2~T3 of the controller, the preheating of the hydraulic oil is completed at this time.

[0068] When the temperature sensor 8 detects that the oil temperature of the hydraulic oil tank 1 is lower than the preset temperature T2 of the controller, at this time, the preheating function of the oil in the tank has a higher priority than the actions of the whole machine. When the temperature of the hydraulic oil tank 1 exceeds T3, at this time, the actions of the whole machine have a higher priority than the preheating of the oil in the tank, that is, the system first executes the one with higher priority, and then executes the subsequent actions after the one with higher priority is completed.

[0069] When the temperature of the hydraulic oil tank 1 is within the range of T2~T3, at this time, the hydraulic oil tank 1 is in a heat preservation state. If other hydraulic systems are working at this time, the preheating function of the hydraulic oil tank 1 is in a silent state; if other hydraulic systems are not working at this time, the preheating function of the hydraulic oil tank 1 is in a wake-up standby state. As long as the oil temperature is lower than T2, at this time, the load-sensitive pump 4 starts to overflow at medium-high pressure and large flow rate, and always maintains the tank temperature within the range of T2~T3 for heat preservation. The settings of T1, T2 and T3 above are determined according to different regions. Because in different regions, the values will be different, but generally follow the principle of T1 < T2 < T3.

[0070] Through the thermal insulation measures of hydraulic oil, it can be avoided that during the working process in a low-temperature environment, the temperature of the hydraulic oil will not drop again to a temperature that is not suitable for the working system after the preheating is completed and provided to the working system for operation, which will affect the normal operation of the hydraulic system and further affect the construction progress and even the safety of personnel; by keeping the temperature of the hydraulic oil under control, the hydraulic oil is kept in a suitable state from beginning to end after preheating, ensuring stable work and being able to adapt well to work in a low-temperature environment.

[0071] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0072] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A hydraulic oil temperature control system for a boom-type aerial work platform, comprising a hydraulic oil tank (1), a hydraulic oil delivery assembly, a working hydraulic system (2), a platform valve (3) and a controller ECU, characterized in that: The hydraulic oil delivery assembly comprises a load-sensitive pump (4), an electromagnetic proportional relief valve (5) and a main control valve group (6), and the controller ECU is electrically connected to the electromagnetic proportional relief valve (5) and the electromagnet of each valve in the main control valve group (6); The electromagnetic proportional relief valve (5) is installed in the oil circuit between the load sensing pump (4) and the main control valve group (6); The pressure oil port P1 of the load sensing pump (4) is connected to the oil inlet port P2 of the main control valve group (6) through a hydraulic pipeline, and the load sensing pressure oil port LS1 of the load sensing pump (4) is connected to the load sensing oil port LS2 of the main control valve group (6); The main control valve group (6) comprises a working control valve group (61) and a platform control valve group (62); the platform control valve group (62) comprises a platform reversing valve (621) and a one-way valve (622); the platform control valve group (62) is arranged at the tail connection of the main control valve group (6); The working control valve group (61) is connected to the pipeline of the working hydraulic system (2), the platform reversing valve (621) is connected to the pipeline of the platform valve (3), the platform reversing valve (621) is a three-position five-way solenoid valve, and the load-sensitive oil port LS3 of the platform reversing valve (621) is connected to the load-sensitive oil port LS2 of the main control valve group (6); An oil return pipeline is connected between the platform valve (3) and the oil cylinder, and the oil return ports of the electromagnetic proportional relief valve (5) and the main control valve group (6) are both in communication with the oil return hydraulic pipeline; A temperature sensor (8) is installed in the hydraulic oil tank (1), and the temperature sensor (8) is connected to a controller ECU via a signal harness.

2. The hydraulic oil temperature control system for a boom-type aerial work platform according to claim 1, characterized in that: The electromagnetic proportional relief valve (5) is integrated and installed in the main control valve group (6), and the electromagnetic proportional relief valve (5) is installed near the inner oil inlet of the main control valve group (6).

3. The hydraulic oil temperature control system of the boom-type aerial work platform according to claim 1 is characterized in that: The electromagnetic proportional relief valve (5) is provided separately and is installed at an outer oil inlet close to the main control valve group (6). The pressure oil port P1 of the load sensing pump (4) is connected to the oil inlet port P3 of the electromagnetic proportional relief valve (5), and the oil inlet port P3 of the electromagnetic proportional relief valve (5) is connected to the oil inlet port P2 of the main control valve.

4. The hydraulic oil temperature control system for a boom-type aerial work platform according to claim 3 is characterized in that: The platform control valve group (62) further comprises a compensation valve (623) arranged on the oil inlet pipeline between the platform reversing valve (621) and the working control valve group (61); the oil return port of the compensation valve (623) is connected to the oil return hydraulic pipeline; the load sensitive oil port LS4 of the compensation valve (623) is connected to the hydraulic pipeline between the load sensitive oil port LS2 of the main control valve group (6) and the load sensitive oil port LS3 of the platform reversing valve (621).

5. The hydraulic oil temperature control system for a boom-type aerial work platform according to claim 1, characterized in that: The load-sensitive pump (4) comprises a one-way variable displacement pump (41) whose oil suction port is connected to the hydraulic oil tank (1), and also comprises a pressure cut-off valve (42) and a load-sensitive valve (43). The one-way variable displacement pump (41) is connected to a power source (7) via a transmission shaft. A speed sensor (71) is provided on the power source (7). The speed sensor (71) is connected to a controller ECU via a signal harness.

6. The hydraulic oil temperature control system for a boom-type aerial work platform according to claim 5, characterized in that: The pressure cut-off valve (42) and the load sensing valve (43) are both two-position three-way valves, and the load sensing oil port LS5 of the load sensing valve (43) is connected to the load sensing oil port LS1 of the load sensing pump (4).

7. The hydraulic oil temperature control system for a boom-type aerial work platform according to claim 4, characterized in that: The platform reversing valve (621) is a three-position five-way reversing solenoid valve with a "Y" type mid-position function. The solenoid valve is closed in the mid-position, and the valve core can output a feedback pressure signal to the load-sensitive oil port LS4 of the compensation valve (623), thereby controlling the load-sensitive valve (43) of the load-sensitive pump (4). The platform reversing valve (621) is designed with electromagnets Y1 and Y2 respectively. When Y2 is energized, the platform reversing valve (621) switches to the right position for operation.

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