A snow thrower and a hydraulic system power control device thereof

Abstract

The application discloses a snow thrower and a hydraulic system power control device thereof, and the hydraulic system power control device comprises a working pump, a walking pump, a control module, an engine, a rotating speed detection module and a pressure detection module. The output end of the engine is connected with the input end of the working pump and the input end of the walking pump, the output end of the engine is connected with the rotating speed detection module, the rotating speed detection module is connected with the control module, the output end of the working pump is connected with the pressure detection module, the pressure detection module is connected with the control module, a rotating speed adjusting instruction receiving module and a displacement adjusting instruction receiving module are connected with the control module, and the control module is connected with the displacement control end of the working pump and the displacement control end of the walking pump. The power control device can control the displacement of the walking pump and the displacement of the working pump at will under the premise of preventing the engine from overspeeding or extinguishing, thereby ensuring that the power of the two pumps is controlled at will, the performance of the two pumps is fully exerted, and the working efficiency of the snow thrower is improved.

Description

Technical Field

[0001] This application relates to the field of snowplow technology, and particularly to a hydraulic system power control device. This application also relates to a snowplow incorporating the hydraulic system power control device. Background Technology

[0002] A snow blower is a type of engineering machinery used to clear thick snow. One characteristic of its hydraulic system is that both the traveling pump and the working pump are powered by an engine and need to operate synchronously. For hydraulic systems like those in snow blowers, where a single power source drives multiple oil pumps, engine anti-stalling control and improving equipment efficiency are issues worthy of continued research.

[0003] In practical applications of existing construction machinery, power control of the hydraulic system is generally not implemented. This can lead to engine over-powering, speed reduction, or stalling due to improper operation. How to control or distribute the power of the hydraulic system directly affects the equipment's performance and efficiency. To solve the problem of engine over-powering and stalling, a common practice is to use a variable displacement pump's power valve to control the hydraulic system with constant power. However, for multi-pump hydraulic systems, the drawback of using this mechanical constant power valve is that the constant power value is always fixed. This means that when one pump is operating at a low load while another is operating at a high load, the power of the high-load pump is limited and cannot function further, thus reducing the equipment's efficiency.

[0004] In view of the above problems, there are existing solutions that employ electronic power control. This involves using a control device to calculate the total power of the entire hydraulic system in real time and compare it with the engine power, then using this comparison to control variable pumps, etc. For example, the solution described in "A Multi-Pump Hydraulic System and Its Power Control Method" uses a concrete pump truck as an example. When the total power of the hydraulic system exceeds the available engine power, the hydraulic system power is reduced by decreasing the displacement of the first variable pump, thus preventing the engine from stalling due to over-power. When the hydraulic system power is less than the available engine power, the engine speed is reduced and the displacement of the first variable pump is increased, thereby improving engine power utilization. However, this solution prioritizes the power of the main pump only when the system experiences excessive power during complex actions, and cannot arbitrarily prioritize the power of the main pump and the first variable pump, thus limiting the performance of the first variable pump. Furthermore, due to the real-time detection of load changes, the system's computational load is correspondingly large.

[0005] Therefore, it is necessary for those skilled in the art to provide a hydraulic system power control device that can guarantee arbitrary priority control of the power of each variable pump while solving the problem of engine over-power shutdown. Summary of the Invention

[0006] The purpose of this application is to provide a snow blower and its hydraulic system power control device, which can ensure that the power of the traveling pump and the working pump can be arbitrarily prioritized, so as to give full play to the performance of the traveling pump and the working pump and improve the working efficiency of the snow blower.

[0007] To achieve the above objectives, this application provides a hydraulic system power control device for use in a snow blower, comprising a working pump, a traveling pump, a control module, an engine, a speed detection module, and a pressure detection module;

[0008] The engine output is connected to the input of the working pump and the input of the traveling pump. The engine output is connected to the speed detection module, which is connected to the control module. The working pump output is connected to the pressure detection module, which is connected to the control module. The control module is connected to the displacement control of the working pump and the displacement control of the traveling pump.

[0009] It also includes a speed adjustment command receiving module and a displacement adjustment command receiving module connected to the control module. The speed adjustment command receiving module transmits the received engine speed adjustment command to the control module to control the engine speed and the displacement of the working pump. The displacement adjustment command receiving module transmits the received travel pump displacement adjustment command to the control module to control the travel pump displacement.

[0010] In some embodiments, the system further includes a first electro-proportional displacement valve, which is connected to the displacement control terminal of the working pump, and the control terminal of the first electro-proportional displacement valve is connected to the control module.

[0011] In some embodiments, a second electro-proportional displacement valve is further included, which is connected to the displacement control terminal of the traveling pump, and the control terminal of the second electro-proportional displacement valve is connected to the control module.

[0012] In some embodiments, the speed adjustment command receiving module is a speed adjustment knob.

[0013] In some embodiments, the displacement adjustment command receiving module is a displacement adjustment knob.

[0014] In some embodiments, a working motor is also included, with the output of the working pump connected to the input of the working motor.

[0015] In some embodiments, a travel motor is also included, with the output end of the travel pump connected to the input end of the travel motor.

[0016] This application also provides a snow blower, including the hydraulic system power control device of any of the above.

[0017] Compared to the aforementioned background technology, the hydraulic system power control device provided in this application embodiment is applied to a snow blower, including a working pump, a traveling pump, a control module, an engine, a speed detection module, a pressure detection module, a speed adjustment command receiving module, and a displacement adjustment command receiving module. The engine's output end is connected to the input ends of the working pump and the traveling pump, and the engine drives both pumps. The engine's output end is connected to the speed detection module, which is connected to the control module, and the speed detection module provides real-time feedback of the engine's current speed to the control module. The working pump's output end is connected to the pressure detection module, which is connected to the control module, and the pressure detection module provides real-time feedback of the working pump's current pressure to the control module. The speed adjustment command receiving module and the displacement adjustment command receiving module are connected to the control module, and the control module is connected to the displacement control ends of the working pump and the traveling pump. Thus, the speed adjustment command receiving module transmits the received engine speed adjustment command to the control module, enabling the control module to control the engine speed and the working pump's displacement. Similarly, the displacement adjustment command receiving module transmits the received traveling pump displacement adjustment command to the control module, enabling the control module to control the traveling pump's displacement.

[0018] It should be noted that the hydraulic system power control device provided in this application embodiment can be applied to a snow blower. When the snow blower is working, the constant power value P2 of the working pump controlled by the control module is variable, and its value is equal to the available power of the engine P0 minus the maximum power P1 of the travel pump. The maximum power P1 of the travel pump is calculated from the current displacement V1 of the travel pump, the current engine speed n, and the snow blower's slippage travel pressure p1. Using the slippage travel pressure p1 for calculation here significantly reduces the system's computational load compared to using a pressure sensor to detect load changes in real time.

[0019] When a snow blower is working, its travel speed and snow-throwing speed need to be adjusted according to the actual situation. When an increase in travel speed is required, the displacement adjustment command receiving module transmits a command to the control module to increase the travel pump's displacement. The control module then calculates the travel pump's maximum power P1 and simultaneously reduces the working pump's constant power value P2, thus ensuring the travel pump's performance is fully utilized and preventing engine stalling due to over-power. Conversely, when a decrease in travel speed is required, the displacement adjustment command receiving module transmits a command to the control module to decrease the travel pump's displacement. The control module then calculates the travel pump's maximum power P1 and simultaneously increases the working pump's constant power value P2, thus ensuring the working pump's performance is fully utilized. This can lead to a relative improvement in the snow blower's working efficiency. When it is necessary to increase the snow-throwing speed, the speed adjustment command receiving module transmits the received command to increase the engine speed to the control module, thereby increasing the engine speed and the displacement of the working pump. If it is found that the snow-throwing speed has not been significantly improved, that is, the power of the working pump is limited by a constant power value, the displacement of the travel pump can be reduced to improve the performance of the working pump. When it is necessary to decrease the snow-throwing speed, the speed adjustment command receiving module transmits the received command to decrease the engine speed to the control module, thereby reducing the engine speed and the displacement of the working pump. At this time, the performance of the travel pump can be relatively improved, and the travel speed can be further increased.

[0020] In summary, the aforementioned hydraulic system power control device, while preventing engine over-power loss or stalling, can control the displacement of the travel pump and the working pump respectively through the displacement adjustment command receiving module and the speed adjustment command receiving module. This allows for arbitrary priority control of either the travel pump's or the working pump's displacement, ensuring optimal power control and maximizing their performance, thus improving the snow blower's efficiency. Simultaneously, the working pump's constant power value is variable but unaffected by changes in travel or working load pressure. This characteristic reduces the system's real-time calculation load and improves operational stability. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of this application. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of the connection of the hydraulic system power control device in the embodiments of this application.

[0023] in:

[0024] 1-Working pump, 2-Working motor, 3-Travel pump, 4-Travel motor, 5-Control module, 6-Engine, 7-Speed ​​detection module, 8-Pressure detection module, 9-Speed ​​adjustment command receiving module, 10-Displacement adjustment command receiving module, 11-First electro-proportional displacement valve, 12-Second electro-proportional displacement valve. Detailed Implementation

[0025] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0026] To enable those skilled in the art to better understand the present application, the present application will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0027] Please refer to Figure 1 , Figure 1 This is a schematic diagram of the connection of the hydraulic system power control device in the embodiments of this application.

[0028] The hydraulic system power control device provided in this application embodiment is applied to a snow blower and includes a working pump 1, a working motor 2, a travel pump 3, a travel motor 4, a control module 5, an engine 6, a speed detection module 7, a pressure detection module 8, a speed adjustment command receiving module 9, and a displacement adjustment command receiving module 10.

[0029] The output end of the working pump 1 is connected to the input end of the working motor 2 to form a closed working circuit. The output end of the traveling pump 3 is connected to the input end of the traveling motor 4 to form a closed working circuit. The output end of the engine 6 is connected to the input ends of the working pump 1 and the traveling pump 3. The engine 6 is used to provide a power source to drive the working pump 1 and the traveling pump 3.

[0030] The output of engine 6 is connected to speed detection module 7, which is connected to control module 5. Speed ​​detection module 7 is used to feed back the current speed of engine 6 to control module 5 in real time.

[0031] The output end of the working pump 1 is connected to the pressure detection module 8, which is connected to the control module 5. The pressure detection module 8 is used to feed back the current pressure of the working pump 1 to the control module 5 in real time.

[0032] Preferably, the speed detection module 7 is an engine speed sensor used to detect the speed of the engine 6, and the pressure detection module 8 is a pressure sensor used to detect the outlet pressure of the working pump 1.

[0033] Control module 5 is connected to the displacement control terminal of working pump 1 and the displacement control terminal of traveling pump 3. Speed ​​adjustment command receiving module 9 is connected to control module 5 to control engine speed 6 and displacement of working pump 1. Displacement adjustment command receiving module 10 is connected to control module 5 to control displacement of traveling pump 3.

[0034] In other words, the engine speed adjustment command received by the speed adjustment command receiving module 9 is transmitted to the control module 5 so that the control module 5 can control the speed of the engine 6 and the displacement of the working pump 1. The displacement adjustment command received by the displacement adjustment command receiving module 10 is transmitted to the control module 5 so that the control module 5 can control the displacement of the travel pump 3.

[0035] It should be noted that the hydraulic system power control device provided in this application embodiment can be applied to a snow blower. When the snow blower is working, the constant power value P2 of the working pump 1 controlled by the control module 5 is variable, and its value is equal to the available power P0 of the engine 6 minus the maximum power P1 of the travel pump 3. The maximum power P1 of the travel pump 3 is calculated from the current displacement V1 of the travel pump 3, the current speed n of the engine 6, and the snow blower's slippage travel pressure p1. Using the slippage travel pressure p1 for calculation here significantly reduces the system's computational load compared to using a pressure sensor to detect load changes in real time. The remaining parameter values ​​and control relationships are shown in Table 1 below.

[0036] Table 1. Snow Thrower Power Control Parameters and Control Relationships

[0037]

[0038]

[0039] When using a snow blower for snow removal, the travel speed and snow-throwing speed need to be adjusted according to the actual situation.

[0040] When it is necessary to increase the walking speed, the displacement adjustment command receiving module 10 transmits the received command to increase the displacement of the walking pump 3 to the control module 5 to increase the displacement of the walking pump 3. At this time, the control module 5 calculates the maximum power P1 of the walking pump 3 and then synchronously reduces the constant power value P2 of the working pump 1 to ensure that the performance of the walking pump 3 can be fully utilized and to prevent the engine 6 from over-powering and stalling. When it is necessary to decrease the walking speed, the displacement adjustment command receiving module 10 transmits the received command to decrease the displacement of the walking pump 3 to the control module 5 to decrease the displacement of the walking pump 3. At this time, the control module 5 calculates the maximum power P1 of the walking pump 3 and synchronously increases the constant power value P2 of the working pump 1 to relatively improve the performance of the working pump 1 and improve the working efficiency of the snow blower.

[0041] When it is necessary to increase the snow-throwing speed, the speed adjustment command receiving module 9 transmits the received command to increase the engine speed of engine 6 to the control module 5, thereby increasing the engine speed of engine 6 and the displacement of working pump 1. If it is found that the snow-throwing speed is not significantly improved, that is, the power of working pump 1 is limited by a constant power value, the displacement of traveling pump 3 can be reduced to improve the performance of working pump 1. When it is necessary to decrease the snow-throwing speed, the speed adjustment command receiving module 9 transmits the received command to decrease the engine speed of engine 6 to the control module 5, thereby reducing the engine speed of engine 6 and the displacement of working pump 1. At this time, the performance of traveling pump 3 can be relatively improved, and the traveling speed can be further increased.

[0042] In summary, the aforementioned hydraulic system power control device, while preventing engine 6 from over-powering and slowing down or stalling, can control the displacement of the travel pump 3 and the working pump 1 respectively through the displacement adjustment command receiving module 10 and the speed adjustment command receiving module 9. This ensures that the power of the travel pump 3 and the working pump 1 can be arbitrarily prioritized, fully utilizing their performance and improving the working efficiency of the snow blower. Simultaneously, the working pump 1's constant power value is variable but unaffected by changes in load pressure; this characteristic reduces the real-time calculation load of the system and improves the stability of system operation.

[0043] In some embodiments, the hydraulic system power control device further includes a first electro-proportional displacement valve 11, which is connected to the displacement control terminal of the working pump 1. The control terminal of the first electro-proportional displacement valve 11 is connected to the control module 5 for signal transmission and is controlled by the speed of the engine 6.

[0044] In some embodiments, the hydraulic system power control device further includes a second electro-proportional displacement valve 12, which is connected to the displacement control terminal of the traveling pump 3. The control terminal of the second electro-proportional displacement valve 12 is connected to the control module 5 to realize signal transmission.

[0045] Preferably, the speed adjustment command receiving module 9 is a speed adjustment knob used to control the engine speed 6 and the displacement of the working pump 1.

[0046] Preferably, the displacement adjustment command receiving module 10 is a displacement adjustment knob used to control the displacement of the walking pump 3.

[0047] Understandably, when the displacement of the travel pump 3 is reduced by adjusting the displacement knob, the maximum power P1 of the travel pump 3 calculated by the control module 5 decreases accordingly. At this time, the constant power value P2 of the working pump 1 increases accordingly, thereby ensuring that the performance of the working pump 1 is fully utilized and improving the working efficiency of the snow blower. Correspondingly, when it is necessary to increase the performance of the travel pump 3, i.e., by increasing the displacement of the travel pump 3 by adjusting the displacement knob, the maximum power P1 of the travel pump 3 calculated by the control module 5 increases accordingly, and the constant power value P2 of the working pump 1 decreases accordingly, thereby ensuring that the engine 6 will not overpower and stall. At the same time, in this scheme, the maximum power P1 of the travel pump 3 is calculated by the displacement V1 of the travel pump 3, the engine speed n of the engine 6, and the travel slip pressure p1 (P1 = p1 × V1 × n / η1, where η1 is the total efficiency of the travel pump 3). That is, the constant power value P2 of the working pump 1 is not affected by changes in load pressure, but is only controlled by the displacement V1 of the travel pump 3 and the engine speed n of the engine 6. This characteristic reduces the real-time calculation load of the system and can improve the stability of system operation.

[0048] The snow blower provided in this application includes the hydraulic system power control device described in the above specific embodiments; other parts of the snow blower can be referred to the prior art, and will not be elaborated here.

[0049] In summary, the snow blower and its hydraulic system power control device provided in this application embodiment can bring the following beneficial effects in a control scheme for driving multiple variable pumps from a single power source:

[0050] 1) The hydraulic system power control device of this application embodiment can ensure that the power of the travel pump 3 and the working pump 1 can be arbitrarily prioritized by manually adjusting the displacement adjustment knob of the travel pump 3 and the speed adjustment knob of the engine 6, so as to give full play to the performance of each variable pump and improve the working efficiency of the snow blower, while preventing the engine 6 from overpowering and slowing down or shutting down.

[0051] 2) During the power control process of the hydraulic system power control device in this application embodiment, the maximum power P1 of the walking pump 3 and the constant power value P2 of the working pump 1 are not affected by the changes in walking and working load pressure, but are only controlled by the displacement V1 of the walking pump 3 and the speed n of the engine 6. This characteristic reduces the real-time calculation of the system and can improve the stability of the system operation.

[0052] 3) In actual operation, the hydraulic system power control device of this application embodiment adjusts the available power of engine 6 at different speeds and the constant power value of working pump 1 according to the power curve of engine 6, thereby improving the power utilization rate of engine 6.

[0053] It should be noted that in this specification, relational terms such as first and second are used only to distinguish one entity from several other entities, and do not necessarily require or imply any such actual relationship or order between these entities.

[0054] The snow thrower and its hydraulic system power control device provided in this application have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this application. The descriptions of the embodiments above are only for the purpose of helping to understand the solution and core ideas of this application. It should be noted that those skilled in the art can make several improvements and modifications to this application without departing from the principles of this application, and these improvements and modifications also fall within the protection scope of the claims of this application.

Claims

1. A hydraulic system power control device, applied to a snow blower, characterized in that, It includes a working pump, a traveling pump, a control module, an engine, a speed detection module, and a pressure detection module; The output end of the engine is connected to the input end of the working pump and the input end of the traveling pump. The output end of the engine is connected to the speed detection module. The speed detection module is connected to the control module. The output end of the working pump is connected to the pressure detection module. The pressure detection module is connected to the control module. The control module is connected to the displacement control end of the working pump and the displacement control end of the traveling pump. It also includes a speed adjustment command receiving module and a displacement adjustment knob connected to the control module. The speed adjustment command receiving module transmits the received engine speed adjustment command to the control module to control the engine speed and the displacement of the working pump. The displacement adjustment knob transmits the received travel pump displacement adjustment command to the control module to control the travel pump displacement. While preventing the engine from overpowering and slowing down or stalling, the displacement of the travel pump and the displacement of the working pump can be controlled separately through the displacement adjustment knob and the speed adjustment command receiving module, ensuring that the power of the travel pump and the working pump can be controlled arbitrarily with priority. When the displacement of the travel pump is reduced by adjusting the displacement knob, the maximum power P1 of the travel pump calculated by the control module decreases accordingly. At the same time, the constant power value P2 of the working pump increases accordingly, ensuring that the performance of the working pump is fully utilized and improving the working efficiency of the snow blower. Conversely, when the performance of the travel pump needs to be increased (i.e., the current displacement is increased by adjusting the displacement knob), the maximum power P1 of the travel pump calculated by the control module increases accordingly, and the constant power value P2 of the working pump decreases accordingly, ensuring that the engine does not over-power and stall. The maximum power P1 of the travel pump is determined by the travel pump... The current displacement V1, the current engine speed n, and the slip pressure p1 are calculated. The slip pressure p1 is input to the control module based on the experimental test value. P1 = p1 × V1 × n / η1, where η1 is the total efficiency of the travel pump. The constant power value of the working pump P2 = P0 - P1, where P0 is the available power of the engine. The available power of the engine P0 is input to the control module based on the engine power curve. That is, the maximum power P1 of the travel pump and the constant power value P2 of the working pump are not affected by changes in travel and working load pressure, but are only controlled by the current displacement V1 of the travel pump and the current engine speed n.

2. The hydraulic system power control device as described in claim 1, characterized in that, It also includes a first electro-proportional displacement valve, which is connected to the displacement control terminal of the working pump, and the control terminal of the first electro-proportional displacement valve is connected to the control module.

3. The hydraulic system power control device as described in claim 1, characterized in that, It also includes a second electro-proportional displacement valve, which is connected to the displacement control terminal of the traveling pump, and the control terminal of the second electro-proportional displacement valve is connected to the control module.

4. The hydraulic system power control device as described in claim 1, characterized in that, The speed adjustment command receiving module is a speed adjustment knob.

5. The hydraulic system power control device as described in claim 1, characterized in that, It also includes a working motor, with the output end of the working pump connected to the input end of the working motor.

6. The hydraulic system power control device as described in claim 1, characterized in that, It also includes a walking motor, with the output end of the walking pump connected to the input end of the walking motor.

7. A snow thrower, characterized in that, Includes the hydraulic system power control device as described in any one of claims 1-6.

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