Hydraulic systems and rollers

Abstract

The present invention provides a hydraulic system and a road roller. The hydraulic system includes: a pressure oil source; an oil tank; a first control valve, the oil inlet of the first control valve is connected to the pressure oil source; a brake, connected to the working oil port of the first control valve; a manual pumping device, connected between the oil tank and the brake; when the road roller is in a first brake release mode, the pressure oil source supplies oil to the brake; when the road roller is in a second brake release mode, the manual pumping device is connected to the oil tank to supply oil to the brake. The hydraulic system of the present invention can release the parking brake through the manual pumping device when the engine is turned off, making it easy to move the road roller to a safe area or maintenance area by means of a trailer or other equipment. At the same time, it can effectively reduce the potential safety hazards caused by the failure of the brake to obtain the required working oil pressure in time due to damage to the road roller, power failure, etc.

Description

Technical Field

[0001] The present invention relates to the technical field of hydraulic transmission and control, and in particular to a hydraulic system of a road roller and a road roller. Background Art

[0002] In the related art, the front and rear drive wheels of the roller are both provided with parking brakes. In order to release the parking brakes, the machine needs to be started by high-pressure oil from a travel pump. However, if the machine fails or cannot be started, the parking brakes cannot be released and the roller cannot be moved. Summary of the invention

[0003] The present invention aims to at least solve or improve one of the technical problems existing in the prior art or related art.

[0004] To this end, one aspect of the present invention provides a hydraulic system for a road roller.

[0005] A second aspect of the present invention provides a road roller.

[0006] In view of this, one aspect of the present invention proposes a hydraulic system for a road roller, comprising: a pressure oil source; an oil tank; a first control valve, the oil inlet of the first control valve is connected to the pressure oil source; a brake, connected to the working oil port of the first control valve; a manual pumping device, connected between the oil tank and the brake; wherein, when the road roller is in a first brake release mode, the pressure oil source supplies oil to the brake; when the road roller is in a second brake release mode, the manual pumping device is connected to the oil tank to supply oil to the brake.

[0007] The hydraulic system of a road roller provided by the present invention comprises a pressure oil source, an oil tank, a first control valve, a manual pumping device and a brake. Specifically, when the hydraulic system is started, if the road roller is in the first brake release mode, the first control valve is controlled to be turned on, that is, the oil inlet of the first control valve and the working oil port are connected, and the brake is connected to the pressure oil source through the first control valve to control the deceleration component connected to the drive device to perform the release operation of the parking brake. When the road roller is in a stopped state and it is necessary to move the road roller, the road roller can be put into the second brake release mode, then the oil inlet of the first control valve is disconnected from the working oil port, and the brake is supplied with oil through the manual pumping device and the oil tank to realize the release of the parking brake in the stopped state. Through the hydraulic system provided by the present invention, it can be ensured that the road roller can still release the parking brake in time through the manual pumping device when the engine is turned off, so that the road roller can be moved to a safe area or a maintenance area by a trailer and other equipment. At the same time, it can effectively reduce the safety hazards caused by the failure of the brake to obtain the required working oil pressure in time due to damage to the road roller, power failure, etc.

[0008] The hydraulic system of the road roller according to the present invention may also have the following additional technical features:

[0009] In the above technical scheme, further, the manual pumping device includes: a reversing valve, a first oil port of the reversing valve is connected to the working oil port of the first control valve, and a second oil port of the reversing valve is connected to the brake; a manual pump, an oil inlet of the manual pump is connected to the first oil port of the reversing valve and the oil tank through a first one-way valve, the conduction direction of the first one-way valve points to the oil inlet of the manual pump, and an oil outlet of the manual pump is connected to the second oil port of the reversing valve and the brake through a second one-way valve, and the conduction direction of the second one-way valve points to the second oil port of the reversing valve and the brake.

[0010] In this technical solution, the manual pumping device includes a reversing valve, a manual pump, a first one-way valve and a second one-way valve. Specifically, when the roller is in a fault or cannot be started, and the roller needs to be moved, the roller can be controlled to enter the second brake release mode. At this time, the oil inlet of the first control valve is disconnected from the working oil port, and the manual pump is connected to the oil tank. At the same time, the reversing valve is controlled to be in the upper position, so that the oil outlet of the manual pump is disconnected from the oil inlet. The handle of the manual pump is pushed and pulled, and the manual pump sucks oil from the oil tank. The pressure oil is transmitted to the brake through the oil outlet of the manual pump through the second one-way valve. Therefore, the parking brake is released in the stopped state by supplying oil through the manual pump, which is conducive to improving the working efficiency of the roller, and improving the adaptability and extensiveness of the product, which is conducive to improving the product's performance and market competitiveness.

[0011] Specifically, the reversing valve may be a manual reversing valve or a solenoid valve. When the reversing valve is a solenoid valve, it is turned on when energized and turned off when energized.

[0012] In any of the above technical schemes, further, the oil return port of the first control valve is connected to the oil tank, and the oil inlet of the manual pump is connected to the first oil port of the reversing valve and the working oil port of the first control valve through the first one-way valve; wherein, when the roller is in the first brake release mode, the oil inlet of the first control valve and the working oil port of the first control valve are connected, and the first oil port of the reversing valve and the second oil port of the reversing valve are connected; when the roller is in the second brake release mode, the working oil port of the first control valve and the oil return port of the first control valve are connected, and the first oil port of the reversing valve and the second oil port of the reversing valve are disconnected.

[0013] In this technical solution, the manual pumping device is connected to the oil tank through the first control valve. Specifically, the oil inlet of the manual pump is connected to the first oil port of the reversing valve and the working oil port of the first control valve through the first one-way valve, so that the switching of the oil supply end is realized by the reversing of the first control valve, simplifying the oil inlet circuit. Among them, based on the roller being in the first brake release mode, the control reversing valve is in the lower position, that is, the first oil port of the reversing valve is connected to the second oil port. At this time, the oil outlet of the manual pump is connected to the oil inlet, and there will be no pressure oil output even if the manual pump handle is pushed or pulled. At the same time, the first control valve is controlled to connect to the pressure oil source and transmit the pressure to the brake to realize the release operation of the parking brake. Based on the roller being in the second brake release mode, the working oil port of the first control valve is controlled to be connected with the oil return port, that is, the oil tank is connected with the manual pump through the first control valve, and the control reversing valve is in the upper position, that is, the first oil port of the reversing valve is disconnected from the second oil port. At this time, the oil outlet of the manual pump is disconnected from the oil inlet, and the handle of the manual pump is pushed and pulled, and the manual pump sucks oil from the oil tank, and the pressure oil is transmitted to the brake through the manual pump oil outlet. Thus, the manual pumping device is used to supply oil, and the parking brake is released in the stopped state, which is conducive to improving the working efficiency of the roller, and improving the adaptability and extensiveness of the product, and is conducive to improving the product's performance and market competitiveness.

[0014] In the above technical solution, further, the hydraulic system of the roller also includes: a first pumping device, connected to the oil tank; a driving device, connected to the first pumping device; a deceleration assembly, connected to the driving device, the deceleration assembly includes a reducer and a gearbox; the brake includes: a front drive brake, connected to the reducer and the manual pumping device; and a rear drive brake, connected to the gearbox and the manual pumping device.

[0015] In this embodiment, after the hydraulic system is started, the first pumping device supplies oil to the driving device to operate the roller. The deceleration assembly is connected to the driving device to realize the deceleration operation of the roller. Specifically, the front wheel of the roller is decelerated by the reducer and the front drive brake, and the rear wheel of the roller is decelerated by the gearbox and the rear drive brake. When the roller is in the second brake release mode, the first control valve is controlled to be disconnected, that is, the pressure oil source is disconnected from the working oil port of the first control valve, and the front and rear brakes are supplied with oil through the oil tank and the manual pumping device to realize the release of the parking brake in the shutdown state. Thereby, it is ensured that the parking brake of the roller can still be released in time through the manual pumping device when the engine is turned off, so that the roller can be moved to a safe area or a maintenance area by a trailer and other equipment. At the same time, it can effectively reduce the safety hazards caused by the failure of the brake to obtain the required working oil pressure in time due to damage to the roller, power failure, etc.

[0016] In any of the above technical solutions, further, the driving device includes: a front drive motor, a first oil port of the front drive motor is connected to the first oil port of the first pumping device, and a second oil port of the front drive motor is connected to the second oil port of the first pumping device; a rear drive motor, a first oil port of the rear drive motor is connected to the first oil port of the first pumping device, and a second oil port of the rear drive motor is connected to the second oil port of the first pumping device.

[0017] In this technical solution, the first pumping device and the front-drive and rear-drive motors can form a closed system, and a single pumping device is used to supply oil to the dual-drive motors. The hydraulic oil output by the first pumping device is freely distributed to the oil circuits where the two drive motors are located, thereby driving the front and rear wheels of the roller at the same time, improving the stability of the roller, facilitating the roller to climb slopes, and thereby improving safety.

[0018] In any of the above technical solutions, it further includes: a diverter valve, the inlet of the diverter valve is connected to the first oil port of the first pumping device, the first outlet of the diverter valve is connected to the first oil port of the front drive motor, and the second outlet of the diverter valve is connected to the first oil port of the rear drive motor; a second control valve, the inlet of the second control valve is connected to the pressure oil source, the working oil port of the second control valve is connected to the control oil port of the diverter valve, and the second control valve is configured to control the diverter valve to switch between natural diversion mode and forced diversion mode.

[0019] In this technical solution, a diverter valve and a second control valve are arranged between the first pumping device and the drive motor, wherein the inlet of the diverter valve is connected to the first oil port of the first pumping device, and the two outlets of the diverter valve are respectively connected to the first oil ports of the front drive motor and the rear drive motor, so that the hydraulic oil enters the front drive motor and the rear drive motor respectively through the diverter valve, thereby driving the dual motors to work. The inlet of the second control valve is connected to the pressure oil source, the working oil port of the second control valve is connected to the control oil port of the diverter valve, and the return oil port of the second control valve is connected to the oil tank. When the second control valve is powered off, the diverter valve is in a natural diversion mode and only plays a connecting role. The hydraulic oil is reasonably distributed according to the change of the external load, that is, the power is pursued when the load is large, and the economy is pursued when the load is light or no load, so as to maximize the efficiency of the roller. When the second control valve is energized, the diverter valve enters the forced diverter mode, and the hydraulic oil is strictly distributed to the two drive motors according to the preset flow ratio, so that the front and rear drive motor speeds are output proportionally, thereby preventing the roller from slipping on one side, improving the roller's adaptive performance, and improving the roller's operating efficiency. At the same time, it also reduces the hydraulic shock of the hydraulic system, which is beneficial to extending the service life of hydraulic components.

[0020] In any of the above technical solutions, the hydraulic system further includes: a first speed sensor connected to the front drive motor; a second speed sensor connected to the rear drive motor; a controller connected to the first speed sensor, the second speed sensor and the second control valve, and the controller is also configured to control the reversing of the second control valve.

[0021] In this technical solution, a first speed sensor is connected to the front drive motor for collecting the speed signal of the front drive motor, and a second speed sensor is connected to the rear drive motor for collecting the speed signal of the rear drive motor. A controller receives the speed signal and outputs a corresponding control signal according to a predetermined control strategy to control the on and off of the second control valve to control the switching of the second control valve, so that the diverter valve can switch between the natural diverter mode and the forced diverter mode, thereby realizing the synchronization or constant proportional performance of the front drive motor and the rear drive motor in the hydraulic system.

[0022] Specifically, after the controller obtains the speed signals of the front drive motor and the rear drive motor, it calculates the speed difference between the front drive motor and the rear drive motor, and determines whether the speed difference exceeds the preset speed range. When the speed difference meets the preset speed range, it indicates that the roller has not experienced unilateral slippage, and the diverter valve works in natural diversion mode; when the speed difference exceeds the preset speed range, it indicates that the roller has experienced unilateral slippage, the second control valve is energized, and the diverter valve works in forced diversion mode.

[0023] Furthermore, the first control valve and the second control valve may be arranged in an integrated manner or independently.

[0024] In any of the above technical solutions, further, the second control valve is an electromagnetic reversing valve.

[0025] In this technical solution, the second control valve is an electromagnetic reversing valve. When the second control valve is energized, the diverter valve is in a forced diverter mode. When the second control valve is de-energized, the diverter valve is in a natural diverter mode.

[0026] Specifically, the second control valve is in a power-off state by default, that is, the diverter valve is in a natural diverter mode.

[0027] In any of the above technical solutions, further, the first pumping device is a closed variable pump.

[0028] In this technical solution, the first pumping device is configured as a closed variable pump, so that the output characteristics can be adjusted within a certain range according to work requirements, thereby facilitating natural diversion operation.

[0029] According to a second aspect of the present invention, a road roller is provided, comprising an engine and the hydraulic system of the road roller provided in the first aspect, wherein the hydraulic system is connected to the engine.

[0030] The road roller provided by the present invention, by adding a manual pumping device, can still supply oil to the brake through the manual pumping device when the engine of the road roller is turned off, thereby releasing the parking brake, thereby facilitating the movement of the road roller to a safe area or maintenance area by means of equipment such as a trailer. At the same time, it can effectively reduce the safety hazard caused by the brake being unable to obtain the required working oil pressure in time due to damage to the road roller, power outage, etc.

[0031] Additional aspects and advantages of the present invention will become apparent from the following description or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0033] Figure 1 A schematic structural diagram of a hydraulic system of a road roller according to an embodiment of the present invention is shown;

[0034] Figure 2 A schematic structural diagram of a hydraulic system of a road roller according to another embodiment of the present invention is shown;

[0035] Figure 3 A schematic structural diagram of a hydraulic system of a road roller according to another embodiment of the present invention is shown;

[0036] Figure 4 A schematic diagram of a diverter valve according to an embodiment of the present invention is shown;

[0037] Figure 5 A schematic diagram of the structure of a manual pump according to a specific embodiment of the present invention is shown.

[0038] in, Figures 1 to 5 The corresponding relationship between the reference numerals and component names in the figure is:

[0039] 110 pressure oil source, 120 first pumping device, 130 first control valve, 140 manual pumping device, 142 reversing valve, 144 manual pump, 146 first one-way valve, 148 second one-way valve, 150 driving device, 152 front drive motor, 154 rear drive motor, 156 first speed sensor, 158 second speed sensor, 160 diverter valve, 162 second control valve, 170 brake, 172 front drive brake, 174 rear drive brake, 182 reducer, 184 rear axle, 190 oil tank, 200 engine, 1442 handle part, 1444 pump body. DETAILED DESCRIPTION

[0040] In order to more clearly understand the above-mentioned purpose, features and advantages of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that the embodiments of the present application and the features in the embodiments can be combined with each other without conflict.

[0041] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Therefore, the protection scope of the present invention is not limited to the specific embodiments disclosed below.

[0042] Refer to the following Figures 1 to 5 A hydraulic system of a road roller and a road roller according to some embodiments of the present invention are described.

[0043] Embodiment 1:

[0044] like Figures 1 to 3 As shown, an embodiment of the first aspect of the present invention provides a hydraulic system for a road roller, including: a pressure oil source 110, an oil tank 190, a first pumping device 120, a first control valve 130, a manual pumping device 140 and a brake 170.

[0045] In detail, the oil inlet of the first control valve 130 is connected to the pressure oil source 110. The brake 170 is connected to the working oil port of the first control valve 130. The manual pumping device 140 is connected between the oil tank 190 and the brake 170. When the roller is in the first brake release mode, the pressure oil source 110 supplies oil to the brake 170; when the roller is in the second brake release mode, the manual pumping device 140 is connected to the oil tank 190 to supply oil to the brake 170.

[0046] In this embodiment, when the hydraulic system is started, if the roller is in the first brake release mode, the first control valve 130 is controlled to be turned on, that is, the inlet of the first control valve 130 is connected to the working oil port, the brake 170 is connected to the pressure oil source 110 through the first control valve 130, and the brake 170 is fed with oil to perform the release operation of the parking brake. When the roller is in a stopped state and needs to be moved, the roller can be put into the second brake release mode, at this time, the first control valve 130 is controlled to be disconnected, and the oil inlet of the first control valve 130 is disconnected from the working oil port, and the brake 170 is supplied with oil through the manual pumping device 140 and the oil tank 190, so as to realize the release of the parking brake in the stopped state. The hydraulic system can ensure that the parking brake of the roller can be released through the manual pumping device 140 when the engine is turned off, thereby facilitating the roller to be moved to a safe area or maintenance area by means of a trailer or other equipment. At the same time, it can effectively reduce the safety hazard of being unable to move the roller due to the brake 170 being unable to obtain the required working oil pressure in time when the roller is damaged or power is off.

[0047] Specifically, the first control valve can be a solenoid valve. When the first control valve is energized, the oil inlet of the first control valve and the working oil port of the first control valve are connected. When the first control valve is de-energized, the working oil port of the first control valve and the oil return port of the first control valve are connected. This facilitates switching of the oil supply circuit between the pressure oil source and the brake and the oil replenishment circuit between the manual pumping device and the brake, so that the roller can still release the brake in the event of a failure or inability to start, thereby improving the adaptability and extensiveness of the product. In addition, the first control valve can also be set as a proportional control valve. During the conduction or shutdown process of the first control valve, the oil supply of the pressure oil source is controlled by controlling the opening of the first control valve.

[0048] Embodiment 2:

[0049] like Figure 1 As shown, according to an embodiment of the present invention, it includes the features defined in any of the above embodiments, and further: the manual pumping device 140 includes: a reversing valve 142, a manual pump 144, a first one-way valve 146 and a second one-way valve 148.

[0050] In detail, the first oil port of the reversing valve 142 is connected to the working oil port of the first control valve 130, and the second oil port of the reversing valve 142 is connected to the brake 170; the oil inlet of the manual pump 144 is connected to the first oil port of the reversing valve 142 and the oil tank 190 through the first check valve 146, and the oil outlet of the manual pump 144 is connected to the second oil port of the reversing valve 142 and the brake 170 through the second check valve 148. The conducting direction of the first check valve 146 points to the oil inlet of the manual pump 144, and the conducting direction of the second check valve 148 points to the second oil port of the reversing valve 142 and the brake 170.

[0051] In this embodiment, when the roller is in a fault or cannot be started, and the roller needs to be moved, the roller can be controlled to enter the second brake release mode, at which time the oil inlet of the first control valve 130 is disconnected from the working oil port, the manual pump 144 is connected to the oil tank 190, and the reversing valve 142 is controlled to be in the upper position, so that the oil outlet of the manual pump 144 is disconnected from the oil inlet, and the handle of the manual pump 144 is pushed and pulled, and the manual pump 144 sucks oil from the oil tank 190, and the pressure oil is transmitted to the brake 170 from the oil outlet of the manual pump 144 through the second one-way valve 162. Thus, the manual pump 144 is used to supply oil, and the parking brake is released in the stopped state, which is conducive to improving the working efficiency of the roller, and improving the adaptability and extensiveness of the product, and is conducive to improving the product's performance and market competitiveness.

[0052] Specifically, the reversing valve 142 may be a manual reversing valve or a solenoid valve. When the reversing valve 142 is a solenoid valve, the reversing valve 142 is connected when it is energized, and is disconnected when it is de-energized.

[0053] Embodiment 3:

[0054] like Figure 2 and Figure 3 As shown, according to an embodiment of the present invention, it includes the features defined in any of the above embodiments, and further: the return oil port of the first control valve 130 is connected to the oil tank, and the oil inlet of the manual pump 144 is connected to the first oil port of the reversing valve 142 and the working oil port of the first control valve 130 through the first one-way valve 146.

[0055] In detail, the roller is in the first brake release mode, the oil inlet of the first control valve 130 and the working oil port of the first control valve 130 are connected, and the first oil port of the reversing valve 142 and the second oil port of the reversing valve 142 are connected; the roller is in the second brake release mode, the working oil port of the first control valve 130 and the oil return port of the first control valve 130 are connected, and the first oil port of the reversing valve 142 and the second oil port of the reversing valve 142 are disconnected.

[0056] In this embodiment, the manual pumping device 140 is connected to the oil tank 190 through the first control valve 130, wherein the oil inlet of the manual pump 144 is connected to the first oil port of the reversing valve 142 and the working oil port of the first control valve 130 through the first one-way valve 146, thereby realizing the switching of the oil supply end through the reversing of the first control valve 130, thereby simplifying the oil inlet circuit.

[0057] Specifically, based on the roller being in the first brake release mode, when the control reversing valve 142 is in the lower position, that is, the first oil port of the reversing valve 142 is connected to the second oil port, the oil outlet and the oil inlet of the manual pump 144 are connected, and there will be no pressure oil output even if the handle of the manual pump 144 is pushed or pulled. At the same time, the first control valve 130 is controlled to connect the pressure oil source 110 and transmit the pressure to the brake 170 to realize the release operation of the parking brake. Based on the roller being in the second brake release mode, the working oil port of the first control valve 130 is controlled to be connected to the oil return port, that is, the manual pumping device 140 is connected to the oil tank 190. At the same time, the control reversing valve 142 is in the upper position, and the oil outlet and the oil inlet of the manual pump 144 are disconnected. At this time, the handle of the manual pump 144 is pushed or pulled, and the manual pump 144 sucks oil from the oil tank 190, and the pressure oil at the outlet of the manual pump 140 is transmitted to the brake 170 from the oil outlet of the manual pump 144. Thus, oil is supplied through the manual pumping device 140 to release the parking brake in the stopped state, which is beneficial to improving the working efficiency of the roller, and improves the adaptability and extensiveness of the product, which is beneficial to improving the product's performance and market competitiveness.

[0058] Specifically, Figure 5 As shown, the manual pump 144 includes a handle portion 1422 and a pump body 1444 .

[0059] Embodiment 4:

[0060] like Figure 3 As shown, according to one embodiment of the present invention, a hydraulic system of a road roller is proposed, including: a pressure oil source 110, an oil tank 190, a first pumping device 120, a first control valve 130, a manual pumping device 140, a front drive brake 172, a rear drive brake 174, a reducer 182, a rear axle 184, a drive device 150, a diverter valve 160, a second control valve 162, and a controller (not shown in the figure).

[0061] In detail, the first pumping device 120 is connected to the oil tank 190. The driving device 150 includes a front drive motor 152 and a rear drive motor 154. The front drive motor 152 is mounted on a reducer 182, and a front drive brake 172 is installed on the reducer 182. The first oil port A of the front drive motor 152 is connected to the first oil port A of the first pumping device 120, and the second oil port B of the front drive motor 152 is connected to the second oil port B of the first pumping device 120. The rear drive motor 154 is mounted on a rear axle 184, and a rear drive brake 174 and a gearbox (not shown in the figure) are installed on the rear axle 184. The first oil port A of the rear drive motor 154 is connected to the first oil port A of the first pumping device 120, and the second oil port B of the rear drive motor 154 is connected to the second oil port B of the first pumping device 120. As shown in FIG. Figure 4 As shown, the inlet P of the diverter valve 160 is connected to the outlet of the first pumping device 120, the first outlet A of the diverter valve 160 is connected to the first oil port A of the front drive motor 152, and the second outlet B of the diverter valve 160 is connected to the first oil port A of the rear drive motor 154. The inlet of the second control valve 162 is connected to the pressure oil source 110, and the working oil port of the second control valve 162 is connected to the control oil port X of the diverter valve 160. The second control valve 162 can control the diverter valve 160 to switch between the natural diverting mode and the forced diverting mode, wherein the second control valve 162 is an electromagnetic reversing valve, and the reversing of the second control valve is controlled by the controller.

[0062] In this embodiment, the front wheels of the roller are decelerated by the reducer 182 and the front drive brake 172, and the rear wheels of the roller are decelerated by the gearbox and the rear drive brake 174. In addition, the first pumping device 120 and the front and rear drive motors 154 can form a closed system, and a single pump is used to supply oil to the dual drive motors. The hydraulic oil output by the first pumping device 120 is freely distributed to the oil circuits where the two drive motors are located, thereby driving the front and rear wheels of the roller at the same time, improving the stability of the roller, facilitating the roller to climb a slope, and thus improving safety.

[0063] In addition, a diverter valve 160 and a second control valve 162 are arranged between the first pumping device 120 and the driving motor, wherein the inlet P of the diverter valve 160 is connected to the first oil port A of the first pumping device 120, and the two outlets of the diverter valve 160 are respectively connected to the first oil ports A of the front drive motor 152 and the rear drive motor 154, so that the hydraulic oil enters the front drive motor 152 and the rear drive motor 154 respectively through the diverter valve 160, thereby driving the dual motors to work.

[0064] Specifically, when the second control valve 162 is powered off, the diverter valve 160 is in a natural diversion mode and only serves as a connection. The hydraulic oil is reasonably distributed according to the changes in the external load, that is, power is pursued when the load is large, and economy is pursued when the load is light or no load, so as to maximize the efficiency of the roller; when the second control valve 162 is energized, the diverter valve 160 enters a forced diversion mode, and the hydraulic oil is strictly distributed to the two drive motors according to a preset flow ratio, so that the speeds of the front drive motor 152 and the rear drive motor 154 are output proportionally, thereby preventing the roller from slipping on one side, improving the adaptive performance of the roller, and improving the operating efficiency of the roller. At the same time, it also reduces the hydraulic shock of the hydraulic system, which is beneficial to extending the service life of the hydraulic components.

[0065] Furthermore, a filter is provided on the oil supply circuit between the oil tank 190 and the first pumping device 120, and the contaminants in the hydraulic oil are intercepted by the filter, so that the hydraulic oil remains clean, ensuring that the hydraulic system can work normally and extending the service life of the pumping device.

[0066] In addition, the first pumping device 120 may be a closed variable displacement pump, which can adjust output characteristics within a certain range according to work requirements, thereby facilitating natural diversion operation.

[0067] Embodiment 5:

[0068] like Figures 1 to 3 As shown, according to an embodiment of the present invention, it includes the features defined in any of the above embodiments, and further: the hydraulic system of the roller also includes: a first rotation speed sensor 156 and a second rotation speed sensor 158.

[0069] In detail, the first speed sensor 156 is connected to the front drive motor 152 for collecting the speed signal of the front drive motor 152 , and the second speed sensor 158 is connected to the rear drive motor 154 for collecting the speed signal of the rear drive motor 154 .

[0070] In this embodiment, the controller receives a speed signal and outputs a corresponding control signal according to a predetermined control strategy to control the on and off power of the second control valve 162 to control the reversing of the second control valve 162, so that the diverter valve 160 can switch between a natural diversion mode and a forced diversion mode, thereby achieving synchronization or constant ratio performance of the front drive motor 152 and the rear drive motor 154 in the hydraulic system.

[0071] Specifically, after the controller obtains the speed signals of the front drive motor 152 and the rear drive motor 154, it calculates the speed difference between the front drive motor 152 and the rear drive motor 154, and determines whether the speed difference exceeds the preset speed range. When the speed difference meets the preset speed range, it indicates that the roller has not slipped on one side, and the diverter valve 160 works in the natural diversion mode; when the speed difference exceeds the preset speed range, it indicates that the roller has slipped on one side, and the diverter valve 160 works in the forced diversion mode.

[0072] Embodiment 6:

[0073] like Figures 1 to 3 As shown, an embodiment of the second aspect of the present invention proposes a road roller, comprising: an engine and the hydraulic system of the road roller proposed in the embodiment of the first aspect, wherein the first pumping device 120 of the hydraulic system is connected to the engine 200 .

[0074] In detail, by adding a manual pumping device 140, the roller can still supply oil to the brake through the manual pumping device 140 when the engine is turned off, thereby releasing the parking brake, thereby facilitating the roller to be moved to a safe area or maintenance area by means of a trailer or other equipment. At the same time, it can effectively reduce the safety hazard caused by the brake being unable to obtain the required working oil pressure in time due to damage to the roller, power outage, etc. Specific embodiment:

[0076] like Figure 3 As shown, the fully hydraulic dual-drive single steel wheel hydraulic system includes a travel pump (first pumping device 120), a brake release solenoid valve (first control valve 130), a manual pump 144, a solenoid valve (second control valve 162), a diverter valve 160, a front drive brake 172, a front drive motor 152, a rear drive motor 154, and a rear drive brake 174.

[0077] In detail, the travel hydraulic system of the fully hydraulic dual-drive single steel wheel roller is driven by a single variable oil pump + dual variable motor. The rear drive motor 154 is installed on the rear axle 184, and a gearbox is provided on the rear axle 184 for rear wheel drive. The front drive motor 152 is installed on the front steel wheel reducer 182, that is, the front drive motor 152 and the front steel wheel reducer 182 are integrated for front wheel drive. The travel pump is a closed variable pump, in which the hydraulic oil output from one working oil port of the oil pump passes through the diverter valve 160, and then enters the front drive motor 152 and the rear drive motor 154 respectively through the diverter valve 160, thereby driving the dual travel motors to work. When the solenoid valve is not energized, the diverter valve 160 has no diversion function and only plays a connecting role. When the solenoid valve is energized, the hydraulic oil entering the diverter valve 160 is strictly distributed to the two motors according to the set flow ratio. When the machine is working, the front drive brake 172 and the rear drive brake 174 are released by the high-pressure oil output after the brake release valve is energized. When the machine is in a stopped state and needs to be moved, the manual pump 144 is used to supply oil to the brake 170 to release the parking brake in the stopped state.

[0078] In this embodiment, the anti-skid mode can be switched by adding the solenoid valve and the diverter valve 160, which solves the problem that the roller is prone to slipping when going uphill or in working conditions with poor adhesion. The parking brake can be released when the roller is stopped by adding the manual pump 144, which improves the working efficiency of the roller and is conducive to improving the performance and market competitiveness of the product.

[0079] In the present invention, the term "plurality" refers to two or more than two, unless otherwise clearly defined. The terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; "connected" can be a direct connection or an indirect connection through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0080] In the description of this specification, the description of the terms "one embodiment", "some embodiments", "specific embodiments", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0081] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A hydraulic system for a road roller, characterized in that: include: Pressure oil source; tank; a first control valve, wherein an oil inlet of the first control valve is connected to a pressure oil source; a brake connected to a working oil port of the first control valve; a manual pumping device connected between the oil tank and the brake; A first pumping device is connected to the oil tank; a filter is provided on the oil supply circuit between the oil tank and the first pumping device; a driving device connected to the first pumping device; A reduction assembly connected to the driving device, the reduction assembly comprising a reducer and a gearbox; The brake comprises: a front drive brake connected to the speed reducer and the manual pumping device; a rear drive brake connected to the gearbox and the manual pumping device; Wherein, the roller is in the first brake release mode, and the pressure oil source supplies oil to the brake; the roller is in the second brake release mode, and the manual pumping device is connected to the oil tank to supply oil to the brake; The manual pumping device comprises: a reversing valve, wherein a first oil port of the reversing valve is connected to a working oil port of the first control valve, and a second oil port of the reversing valve is connected to the brake; A manual pump, wherein the oil inlet of the manual pump is connected to the first oil port of the reversing valve and the oil tank through a first one-way valve, the conducting direction of the first one-way valve points to the oil inlet of the manual pump, and the oil outlet of the manual pump is connected to the second oil port of the reversing valve and the brake through a second one-way valve, and the conducting direction of the second one-way valve points to the second oil port of the reversing valve and the brake; The oil return port of the first control valve is connected to the oil tank, and the oil inlet of the manual pump is connected to the first oil port of the reversing valve and the working oil port of the first control valve through the first one-way valve; Among them, the road roller is in the first brake release mode, the oil inlet of the first control valve and the working oil port of the first control valve are connected, and the first oil port of the reversing valve and the second oil port of the reversing valve are connected; the road roller is in the second brake release mode, the working oil port of the first control valve and the oil return port of the first control valve are connected, and the first oil port of the reversing valve and the second oil port of the reversing valve are disconnected.

2. The hydraulic system of a road roller according to claim 1, characterized in that: The driving device comprises: A front drive motor, wherein a first oil port of the front drive motor is connected to a first oil port of the first pumping device, and a second oil port of the front drive motor is connected to a second oil port of the first pumping device; A rear drive motor, wherein a first oil port of the rear drive motor is connected to a first oil port of the first pumping device, and a second oil port of the rear drive motor is connected to a second oil port of the first pumping device.

3. The hydraulic system of a road roller according to claim 2, characterized in that: Also includes: A diverter valve, wherein the inlet of the diverter valve is connected to the first oil port of the first pumping device, the first outlet of the diverter valve is connected to the first oil port of the front drive motor, and the second outlet of the diverter valve is connected to the first oil port of the rear drive motor; A second control valve, wherein the inlet of the second control valve is connected to the pressure oil source, the working oil port of the second control valve is connected to the control oil port of the diverter valve, and the second control valve is configured to control the diverter valve to switch between a natural diversion mode and a forced diversion mode.

4. The hydraulic system of a road roller according to claim 3, characterized in that: Also includes: A first speed sensor connected to the front drive motor; A second speed sensor connected to the rear drive motor; A controller is connected to the first rotation speed sensor, the second rotation speed sensor and the second control valve, and the controller is also configured to control the switching of the second control valve.

5. The hydraulic system of a road roller according to claim 3, characterized in that: The second control valve is an electromagnetic reversing valve.

6. The hydraulic system of a road roller according to claim 1, characterized in that: The first pumping device is a closed variable displacement pump.

7. A road roller, characterized in that: include: engine; The hydraulic system of a road roller according to any one of claims 1 to 6, wherein the hydraulic system is connected to the engine.

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