CN216112112U

CN216112112U - Power shift transmission and hydraulic control device thereof

Info

Publication number: CN216112112U
Application number: CN202120151287.3U
Authority: CN
Inventors: 胡建飞; 史源; 陈程; 胡建华
Original assignee: Hangzhou Advance Gearbox Group Co Ltd
Current assignee: Hangzhou Advance Gearbox Group Co Ltd
Priority date: 2021-01-20
Filing date: 2021-01-20
Publication date: 2022-03-22
Anticipated expiration: 2031-01-20

Abstract

The utility model discloses a power gear shifting transmission and a hydraulic control device thereof, wherein the device comprises a hydraulic control oil path and a control valve group, wherein the hydraulic control oil path is connected with an oil source and comprises a main oil path and at least three oil distribution paths communicated with the main oil path; the control valve group comprises a first electromagnetic directional valve, a second electromagnetic directional valve, a third electromagnetic directional valve, a fourth electromagnetic directional valve, a first hydraulic directional valve, a second hydraulic directional valve, a third hydraulic directional valve, a fourth hydraulic directional valve, a first proportional valve and a second proportional valve. The hydraulic control device can dynamically control the starting and gear shifting process of the transmission, so that the starting and gear shifting process of the transmission is more stable.

Description

Power shift transmission and hydraulic control device thereof

Technical Field

The utility model relates to a control device of a transmission, in particular to a power gear shifting transmission and a hydraulic control device thereof.

Background

Heavy engineering vehicles, such as road rollers and the like, have large dead weight, are combined with application environments, have high requirements on climbing gradient and large variation range of walking driving torque, and are difficult to meet the requirements even though a hydraulic driving system with a large speed change range is adopted.

The traditional road roller power transmission device is composed of a main clutch and a power box or a power box with a torque converter or directly the power box with the torque converter, the required performance requirement is ensured, but the main clutch needs to be operated manually, the labor intensity of a driver is high, the driver needs skilled technology to have good performance, and the service life of the main clutch is short; the power box with the torque converter has the functions of buffering and improving torque, but has low efficiency and high cost.

SUMMERY OF THE UTILITY MODEL

Based on the technical problems, the utility model aims to provide a hydraulic control device, and the transmission structure is beneficial to realizing automation of a starting and gear shifting process and can also carry out dynamic starting and gear shifting control, so that the starting and gear shifting process is more stable.

A second object of the present invention is to provide a transmission in which the above-described hydraulic control apparatus is provided.

In order to achieve the above object, the present invention provides a hydraulic control device, which includes a hydraulic control oil path connected to an oil source and a control valve group, wherein the hydraulic control oil path includes a main oil path and at least three oil distribution paths communicated with the main oil path, an oil pump is disposed on the main oil path, and the control valve group is disposed on the oil distribution paths and used for controlling the on-off of each oil distribution path;

the control valve group comprises a first electromagnetic reversing valve, a second electromagnetic reversing valve, a third electromagnetic reversing valve, a fourth electromagnetic reversing valve, a first hydraulic reversing valve, a second hydraulic reversing valve, a third hydraulic reversing valve, a fourth hydraulic reversing valve, a first proportional valve and a second proportional valve, wherein the first electromagnetic reversing valve, the second electromagnetic reversing valve, the third electromagnetic reversing valve and the fourth electromagnetic reversing valve are respectively connected to the downstream of the first oil distributing passage; the first hydraulic reversing valve is connected to the downstream of the second oil distributing passage, and the third hydraulic reversing valve is communicated with the first hydraulic reversing valve; the first proportional valve and the second proportional valve are respectively communicated with the third hydraulic reversing valve; the fourth hydraulic reversing valve is connected to the downstream of the third oil dividing passage, and the second hydraulic reversing valve is communicated with the fourth hydraulic reversing valve, wherein the first proportional valve is used for being connected with a first directional clutch of the power shift transmission, and the second proportional valve is used for being connected with a second directional clutch of the power shift transmission; the first electromagnetic directional valve, the second electromagnetic directional valve, the third electromagnetic directional valve and the fourth electromagnetic directional valve are communicated with each other and carry out combined control on a first gear shifting clutch, a second gear shifting clutch and a third gear shifting of the power gear shifting transmission.

Preferably, a pressure control valve is further provided upstream of the second oil distribution passage, and a downstream of the second oil distribution passage is further communicated with a fourth hydraulic directional control valve and a second hydraulic directional control valve for finely adjusting an oil pressure of an oil passage communicating the first hydraulic directional control valve, the second hydraulic directional control valve, the third hydraulic directional control valve and the fourth hydraulic directional control valve.

Preferably, the output end of the oil pump is further connected with a fourth oil dividing line, a pressure measuring device is arranged at a junction of the upstream of the four oil dividing lines, and a main pressure valve is arranged on the fourth oil dividing line and used for draining redundant oil pressure when the pressure at the junction is too limited, so that the oil pressure of the first oil dividing line, the second oil dividing line and the third oil dividing line is maintained within a limited pressure range.

Preferably, the limiting pressure is in the range of 1.3-1.7 MPa.

Preferably, a third throttle valve is disposed downstream of the fourth oil dividing passage.

Preferably, a cooler is further provided between the main pressure valve and the third throttle valve of the fourth oil distribution passage.

Preferably, a first check valve and a second check valve are provided in a passage through which the second branch oil passage communicates with the first hydraulic directional control valve and the fourth hydraulic directional control valve, respectively.

Preferably, a first throttle valve and a second throttle valve are provided upstream of the second branch passage and the third branch passage, respectively.

Preferably, the output end of the oil pump is further provided with a safety valve.

In another aspect of the utility model, a power shift transmission is provided, which comprises a box body and a transmission device arranged in the box body, wherein the box body is also provided with the hydraulic control device.

Compared with the prior art, the utility model has the beneficial effects that:

the utility model can be applied to a power gear shifting transmission, and dynamically controls the starting and gear shifting processes of the transmission by adjusting the control oil pressure of different valves in the control valve group, so that the starting and gear shifting processes are more stable.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments of the application and, together with the description, serve to explain the application and are not intended to limit the application.

FIG. 1 is a schematic illustration of the gearing of a powershift transmission in an embodiment of the present invention;

FIG. 2 is a coupling configuration diagram of a hydraulic control device in a powershift transmission according to an embodiment of the present invention;

FIG. 3 is a schematic illustration of the linkage arrangement of the control system of the powershift transmission in an embodiment of the present invention;

FIG. 4 is a flow chart of a method of controlling a powershift transmission in an embodiment of the present invention;

FIG. 5 is a pressure control curve during a flat launch or shift of the powershift transmission in an embodiment of the present invention;

FIG. 6 is a pressure control curve during hill start of the powershift transmission in an embodiment of the present invention;

FIG. 7 is a frame diagram of the drive train of a single drum roller;

FIG. 8 is a flow chart of a method of starting shift control for a single drum road roller;

FIG. 9 is a graph of the change in speed of the engine N1 and the powershift transmission N2 during a launch shift of the single-drum compactor in accordance with an embodiment of the present invention;

wherein, 1, a power shift transmission; 2. a hydraulic control device; 3. a controller; 4. an operating handle; 5. a sampling unit; 6. a gear display unit;

101. a transmission input shaft; 102. a first drive shaft; 103. a second drive shaft; 104. a third drive shaft; 105. a transmission output shaft; 106. a first input gear; 107. a second input gear; 108. a first directional clutch; 109. a first drive gear; 110. a first gear clutch; 111. a first output gear; 112. a third input gear; 113. a second directional clutch; 114. a second transmission gear; 115. a second gear clutch; 116. a second output gear; 117. a third output gear; 118. a third transmission gear; 119. a third gear clutch; 120. a fourth output gear; 121. a fifth output gear; 122. a sixth output gear;

201. a first oil distribution path; 202. a second oil distribution path; 203. a third oil distribution path; 204. a fourth oil distribution passage; 205. a source of oil; 206. A first electromagnetic directional valve; 207. a second electromagnetic directional valve; 208. a third electromagnetic directional valve; 209. a fourth electromagnetic directional valve; 210. a first hydraulic directional control valve; 211. a second hydraulic directional control valve; 212. a third hydraulic directional control valve; 213. a fourth hydraulic directional control valve; 214. a first proportional valve; 215. a second proportional valve; 216. a pressure control valve; 217. a pressure measuring device; 218. a first check valve; 219. a second one-way valve; 220. a first throttle valve; 221. a second throttle valve; 222. a third throttle valve; 223. A cooler; 224. a safety valve; 225. an oil pump; 226. a fine filter; 227. a primary pressure valve.

Detailed Description

The utility model is further described with reference to the following figures and examples.

It should be noted that the following detailed description is exemplary and is intended to provide further explanation of the disclosure. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments according to the present application. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, and it should be understood that when the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof, unless the context clearly indicates otherwise.

In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "clockwise", "counterclockwise", and the like, indicate orientations and positional relationships based on those shown in the drawings, and are used only for convenience of description and simplicity of description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, are not to be construed as limiting the present invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, unless otherwise specified, "a plurality" means two or more unless explicitly defined otherwise.

In the present invention, unless otherwise expressly specified or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In the present invention, unless otherwise expressly stated or limited, "above" or "below" a first feature means that the first and second features are in direct contact, or that the first and second features are not in direct contact but are in contact with each other via another feature therebetween. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly on and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature includes the first feature being directly under and obliquely below the second feature, or simply meaning that the first feature is at a lesser elevation than the second feature.

A power shifting transmission comprises a hydraulic control device 2 and a transmission device, wherein the transmission device comprises a transmission input shaft 101, a first transmission shaft 102, a second transmission shaft 103, a third transmission shaft 104 and a transmission output shaft 105 which are arranged side by side, wherein a first input gear 106 is arranged on the transmission input shaft 101; a second input gear 107, a first direction clutch 108, a first transmission gear 109, a first gear clutch 110 and a first output gear 111 are sequentially mounted on the first transmission shaft 102 from left to right, and the second input gear 107, the first transmission gear 109 and the first output gear 111 are all connected with the first transmission shaft 102 through bearings; a third input gear 112, a second directional clutch 113, a second transmission gear 114, a second gear clutch 115, a second output gear 116 and a third output gear 117 are sequentially mounted on the second transmission shaft 103 from left to right, and the third input gear 112, the second transmission gear 114, the second output gear 116 and the third output gear 117 are all connected with the second transmission shaft 103 through bearings; a third transmission gear 118, a third gear clutch 119, a fourth output gear 120 and a fifth output gear 121 are sequentially mounted on the third transmission shaft 104 from left to right, and the third transmission gear 118, the fourth output gear 120 and the fifth output gear 121 are all connected with the third transmission shaft 104 through bearings; a sixth output gear 122 is mounted on the transmission output shaft 105;

the first input gear 106 is meshed with the second input gear 107, so that the rotation speed of the transmission input shaft 101 is transmitted into the transmission through the second input gear 107; at the same time, the first input gear 106 meshes with the third input gear 112, so that the rotational speed of the transmission input shaft 101 can be reversely transmitted into the transmission through the third input gear 112;

one side of the second transmission gear 114 is meshed with the first transmission gear 109, and the other side of the second transmission gear 114 is meshed with the third transmission gear 118, so that the first transmission gear 109, the second transmission gear 114 and the third transmission gear 118 are linked, the first output gear 111 is meshed with the second output gear 116, the second output gear 116 is linked with the third output gear 117, the third output gear 117 is meshed with the fourth output gear 120, and the fourth output gear 120 is linked with the fifth output gear 121; therefore, the output speed ratios of different gears of the transmission are adjusted by setting the root circle diameters of the gears corresponding to the different gears to different specifications and combining the control of the clutch. The transmission structure removes the traditional structure of a main clutch and a torque converter, adopts a transmission structure of two-direction clutches and three-gear clutches, applies a hydraulic valve group for control, sets the root circle diameters of the gears corresponding to different gears into different specifications, and adjusts the output speed ratios of the different gears of the transmission by combining the electromagnetic and hydraulic combined control of the clutches; the automatic starting and gear shifting control system is beneficial to realizing the automation of the starting and gear shifting process, and can also carry out dynamic starting and gear shifting control, so that the starting and gear shifting process is more stable.

Preferably, the root circle diameters of the first output gear 111 and the third output gear 117 are smaller than the root circle diameter of the second output gear 116 engaged therewith, the root circle diameter of the third output gear 117 is smaller than the root circle diameter of the fourth output gear 120, and the root circle diameter of the fifth output gear 121 is smaller than the root circle diameter of the fourth output gear 120; when the transmission is set to the first-gear output, four-stage continuous speed reduction is formed among the first output gear 111, the second output gear 116, the third output gear 117, the fourth output gear 120 and the fifth output gear 121 to obtain a first-gear speed;

when the transmission is set to two-gear output, two-stage continuous speed reduction is formed among the third output gear 117, the fourth output gear 120 and the fifth output gear 121 to obtain a second gear speed;

when the transmission is set to a three speed output, the output speed of the transmission is close to or the same as the input speed of the transmission.

Preferably, the gear ratio of the first gear is Q1, the gear ratio of the second gear is Q2, and the gear ratio of the third gear is Q3, which have the following value ranges: Q1E [5.521, 8.936], Q2E [2.807, 4.543], Q3E [1.719, 1.900 ].

In particular, the transmission ratio is preferably as shown in table 1 for 4 sets of parameters:

TABLE 1 Transmission ratios

As a preferred embodiment, the transmission further includes a box, and the first transmission shaft 102, the second transmission shaft 103, the third transmission shaft 104, and the gears and clutches on the transmission shafts are all disposed in the box.

As a preferred embodiment, the hydraulic control device 2 is disposed in a box and connected to the first direction clutch 108, the second direction clutch 113, the first gear clutch 110, the second gear clutch 115 and the third gear clutch 119 respectively for driving them to engage or disengage, so as to determine the rotation speed and the rotation direction of the transmission output shaft 105. Specifically, the method comprises the following steps: the hydraulic control device 2 realizes the switching among all gears by controlling the on-off combination of all gear clutches; the dynamic control of the clutch combination process in the corresponding direction is adopted to realize the smooth starting and gear shifting of the transmission, thereby realizing the change of speed and direction.

The embodiment further provides a hydraulic control device 2 of a transmission, where the hydraulic control device 2 may be applied to the power shift transmission 1, and includes a hydraulic control oil path connected to the oil source 205 and a control valve group, where the hydraulic control oil path includes a main oil path and at least three oil distribution paths communicated with the main oil path, the main oil path is provided with an oil pump 225, and the control valve group is disposed on the oil distribution paths and is used to control on/off of each oil distribution path; preferably: the control valve group is respectively connected with the first direction clutch, the second direction clutch, the first gear clutch, the second gear clutch and the third gear clutch, and switching among gears is realized by controlling on-off of each gear clutch; the transmission is stably started and shifted by dynamically controlling the clutch combination process in the corresponding direction.

As shown in fig. 2, the valve group includes a first electromagnetic directional valve 206, a second electromagnetic directional valve 207, a third electromagnetic directional valve 208, a fourth electromagnetic directional valve 209, a first hydraulic directional valve 210, a second hydraulic directional valve 211, a third hydraulic directional valve 212, a fourth hydraulic directional valve 213, a first proportional valve 214, and a second proportional valve 215, where the first electromagnetic directional valve 206, the second electromagnetic directional valve 207, the third electromagnetic directional valve 208, and the fourth electromagnetic directional valve 209 are respectively connected to the downstream of the first oil distribution path 201 (it is to be noted that, it is assumed here that the direction of the oil path close to the oil source 205 is the upstream, and the direction of the oil path far from the oil source 205 is the downstream); the first hydraulic directional valve 210 is connected downstream of the second branch oil passage 202, and the third hydraulic directional valve 212 is communicated with the first hydraulic directional valve 210; the first proportional valve 214 and the second proportional valve 215 are respectively communicated with the third hydraulic directional valve 212; the fourth hydraulic directional valve 213 is connected to the downstream of the third oil dividing passage 203, the second hydraulic directional valve 211 is communicated with the fourth hydraulic directional valve, wherein the first proportional valve 214 is connected with the first directional clutch 108 and is used for controlling the connection or disconnection between the first directional clutch 108 and the transmission shaft where the first directional clutch is located, and the second proportional valve 215 is connected with the second directional clutch 113 and is used for controlling the connection or disconnection between the second directional clutch 113 and the transmission shaft where the second directional clutch is located; the first electromagnetic directional valve 206, the second electromagnetic directional valve 207, the third electromagnetic directional valve 208 and the fourth electromagnetic directional valve 209 are communicated with each other and perform combined control on the first shifting clutch, the second shifting clutch and the third shifting, so that the combined regulation of the rotating direction and the output speed of the transmission is realized through the combined control of the control valve group.

In a preferred embodiment, a pressure control valve 216 is further provided upstream of the second oil distribution passage 202, the fourth hydraulic directional control valve 213 and the second hydraulic directional control valve 211 are further communicated downstream of the second oil distribution passage 202, and the pressure control valve 216 is used for fine adjustment of the oil pressure in the oil passages communicating the first hydraulic directional control valve 210, the second hydraulic directional control valve 211, the third hydraulic directional control valve 212 and the fourth hydraulic directional control valve 213.

In a preferred embodiment, a fourth oil dividing path 204 is further connected to the output end of the oil pump 225, a pressure measuring device 217 is disposed at the junction of the upstream of the four oil dividing paths, and a main pressure valve 227 is disposed on the fourth oil dividing path, and the main pressure valve 227 is configured to drain off excess oil pressure when the pressure at the junction is too limited, so as to maintain the oil pressure of the first oil dividing path 201, the second oil dividing path 202 and the third oil dividing path 203 within a limited pressure range.

As a preferred embodiment, the limiting pressure is in the range of 1.3 to 1.7 MPa.

In a preferred embodiment, a first check valve 218 and a second check valve 219 are provided in a passage in which the second branch oil passage 202 communicates with the first hydraulic directional valve 210 and the fourth hydraulic directional valve 213, respectively.

In a preferred embodiment, a first throttle valve 220 and a second throttle valve 221 are provided upstream of the second branch passage 202 and the third branch passage 203, respectively.

As a preferred embodiment, the output end of the oil pump 225 is further provided with a relief valve 224.

As a preferred embodiment, a third throttle valve 222 is disposed downstream of the fourth oil distribution passage 204.

As a preferred embodiment, a cooler 223 is further disposed between the main pressure valve 227 and the third throttle valve 222 of the fourth oil distribution passage 204.

The powershift transmission 1 is preferably used on a road roller, and therefore the embodiment also provides a road roller with the powershift transmission 1.

The present embodiment also provides a control system of a powershift transmission 1, as shown in fig. 3, including: controller 3, operating handle 4, sampling unit 5, fender position display unit 6 and hydraulic control device 2, controller 3 respectively with operating handle 4, sampling unit 5, fender

position display unit

6 and 2 electric connection of hydraulic control device, wherein:

the operating handle 4 is used for sending direction, gear shifting, hill starting and vibration starting signals;

the sampling unit 5 is used for acquiring the current output rotating speed of the transmission and the inclination angle of the vehicle;

the gear display unit 6 is used for displaying the output gear, the direction and the diagnosis information of the current transmission;

the hydraulic control device 2 comprises a main oil path connected with the oil source 205 and at least three oil distribution paths communicated with the main oil path, the control valve group is arranged on the oil distribution paths, the control valve group is respectively connected with a directional clutch and a gear clutch in the power gear shifting transmission 1, and the output transmission ratio of the transmission is adjusted by controlling the connection or disconnection of each gear clutch and a corresponding transmission shaft; the dynamic adjustment of the torque transmitted by the directional clutch is realized by dynamically controlling the combination process of the main driving disc and the auxiliary driving disc of the directional clutch, so that the starting and gear shifting process is smoother;

and the controller 3 responds to a starting or gear shifting signal, adjusts the on-off of the control oil pressure of the gear clutch and continuously adjusts the control oil pressure of the directional clutch.

As a preferred embodiment, as shown in fig. 2, the hydraulic control device 2 includes a main oil path and at least three branch oil paths communicated with the main oil path, an oil pump 225 is disposed on the main oil path, and the control valve set is disposed on the branch oil paths and is used for controlling on/off of each branch oil path;

the control valve group comprises a first electromagnetic directional valve 206, a second electromagnetic directional valve 207, a third electromagnetic directional valve 208, a fourth electromagnetic directional valve 209, a first hydraulic directional valve 210, a second hydraulic directional valve 211, a third hydraulic directional valve 212, a fourth hydraulic directional valve 213, a first proportional valve 214 and a second proportional valve 215, wherein the first electromagnetic directional valve 206, the second electromagnetic directional valve 207, the third electromagnetic directional valve 208 and the fourth electromagnetic directional valve 209 are respectively connected to the downstream of the first oil distribution passage 201 (it needs to be explained, it is assumed here that the direction of the oil passage close to the oil source 205 is the upstream, and the direction of the oil passage far away from the oil source 205 is the downstream); the first hydraulic directional valve 210 is connected downstream of the second branch oil passage 202, and the third hydraulic directional valve 212 is communicated with the first hydraulic directional valve 210; the first proportional valve 214 and the second proportional valve 215 are respectively communicated with the third hydraulic directional valve 212; the fourth hydraulic directional valve 213 is connected to the downstream of the third oil dividing passage 203, and the second hydraulic directional valve 211 is communicated with the fourth hydraulic directional valve, wherein, as shown in fig. 2, the first proportional valve 214 is connected with the first directional clutch 108 for controlling the connection or disconnection between the first directional clutch 108 and the transmission shaft where the first directional clutch is located, and the second proportional valve 215 is connected with the second directional clutch 113 for controlling the connection or disconnection between the second directional clutch 113 and the transmission shaft where the second directional clutch is located; the first electromagnetic directional valve 206, the second electromagnetic directional valve 207, the third electromagnetic directional valve 208 and the fourth electromagnetic directional valve 209 are communicated with each other and perform combined control on the first shifting clutch, the second shifting clutch and the third shifting, so that the combined regulation of the rotating direction and the output speed of the transmission is realized through the combined control of the control valve group.

In a preferred embodiment, a pressure control valve 216 is further provided upstream of the second oil distribution passage 202, a fourth hydraulic directional control valve 213 and a second hydraulic directional control valve 211 are further communicated downstream of the second oil distribution passage 202, and the pressure control valve 216 is used for fine adjustment of the oil pressure in the oil passage communicating with the first hydraulic directional control valve 210, the second hydraulic directional control valve 211, the third hydraulic directional control valve 212 and the fourth hydraulic directional control valve 213.

In a preferred embodiment, a fourth oil dividing path 204 is further connected to an output end of the oil pump 225, a pressure measuring device 217 is disposed at a junction upstream of the four oil dividing paths, and a main pressure valve 227 is disposed on the fourth oil dividing path, and the main pressure valve 227 is configured to drain off excess oil pressure when the pressure at the junction is too high to limit the pressure, so that the oil pressures of the first oil dividing path 201, the second oil dividing path 202, and the third oil dividing path 203 are maintained within a limited pressure range.

The gear control logic of the control valve group is shown in table 2:

TABLE 2 Shift control logic for control valve group

In a preferred embodiment, the operating handle 4 is provided with a plurality of control buttons for inputting operating requirements.

As a preferred embodiment, the sampling unit includes angular velocity sensors respectively disposed on the input shaft and the output shaft of the powershift transmission 1 and a gradient sensor disposed at the bottom of the powershift transmission 1.

In a preferred embodiment, the gear display unit 6 is used for displaying the output gear, the traveling direction and the diagnosis information of the current transmission.

The embodiment also provides a control method based on the power shift transmission, as shown in fig. 4, the method includes the following steps:

responding to a starting or gear shifting demand, applying pressure to a corresponding gear clutch to realize setting of a speed gear;

applying a first control oil pressure P1 to the control valve of the clutch in the corresponding direction to quickly eliminate the clearance of a main driving disc and a driven disc to prepare for sliding grinding;

rapidly reducing the control oil pressure of the control valve to be close to the effective sliding grinding pressure, so that the main driving disc and the auxiliary driving disc of the directional clutch start sliding grinding;

gradually and gently increasing the control oil pressure of the control valve to gradually increase the transmitted torque of the clutch in the driving direction of the control valve and the main driving disc and gradually approach the rotating speed of the gear connected with the main driving disc and the auxiliary driving disc;

when the control oil pressure of the control valve is increased to the full pressure P, the direction clutch master-slave driving disks are completely combined, so that the gear connected with the direction clutch rotates synchronously.

As a preferred embodiment, the step setting is realized by applying pressure to the corresponding step clutch, specifically: oil pressure is applied to a reversing valve connected with the gear clutch, so that the control valve pushes the gear clutch to combine with the driving and driven discs, and gears connected with the driving and driven discs can synchronously rotate.

In a preferred embodiment, the first oil pressure P1E [1/4P, 2/5P ]. When the total pressure is 20bar, P1 is preferably 6 bar.

As a preferred embodiment, as shown in fig. 5, when the starting gear shift demand is a flat ground starting or a flat ground gear shift, the time t1 required for increasing the control oil pressure of the control valve to the full pressure is 2-3s, and the process is a gentle boosting process, so that the starting or gear shift process is smooth.

As a preferred embodiment, as shown in fig. 6, when the starting requirement is hill starting, the step of increasing the control oil pressure of the control valve to full pressure specifically includes a gap elimination step and a rapid combination step, where t2 of the gap elimination step is 40-100ms, and t3 of the rapid combination step is 60-100ms, which are faster than those of flat starting, and the purpose is to rapidly combine the main clutch and the secondary clutch of the corresponding directional clutch, and to rapidly synchronize the gears connected to the corresponding directional clutch, so as to ensure rapid starting of heavy machinery such as a road roller, and avoid slope slipping.

As a preferred embodiment, the effective sliding pressure corresponds to the control oil pressure P2E [1/5P, 1/4P ].

As a preferred embodiment, the method further comprises the steps of responding to a power reversing demand, controlling the clutch in the current direction to be disconnected, and controlling the clutch in the other direction to be gently combined to execute a reverse smooth starting action when the output speed of the power shifting transmission is lower than the set safe reversing speed.

As a preferred embodiment, the directional clutch is controlled to be disconnected in response to a brake signal until the brake signal is cancelled, and the same gear is started if the current gear is 1 or 2; and if the current gear is the 3-gear, starting from the 2-gear and then increasing to the 3-gear.

The embodiment also provides a single-steel-wheel road roller which is provided with the starting gear-shifting control system.

The embodiment provides a starting and gear shifting control method for a single-drum road roller, which comprises the following steps as shown in fig. 7 and 8:

in response to a starting signal or a gear shifting signal, disconnecting the engine from a transmission part of the transmission, and reducing the rotating speed of the engine from the accelerator control rotating speed to a set starting gear shifting speed within the time T1 and keeping the rotating speed;

applying pressure to a corresponding gear clutch in the power gear shifting transmission 1 to realize the setting of a speed gear; applying pressure to the directional clutch of the powershift transmission 1 to progressively establish a connection with the engine output shaft during time T2 to increase the transmission output speed to a first speed attained at the gear ratio;

the rotating speed of the engine is controlled to be increased to the control rotating speed of the crude throttle within the time T3, the rotating speed of the transmission is increased to the output speed of the set gear along with the control rotating speed, wherein T1 is more than or equal to 200ms and less than or equal to 500ms, T2 is more than or equal to 2s and less than or equal to 3s, and T3 is more than or equal to 2s and less than or equal to 3 s. When starting or gear shifting starts, the engine is controlled to be decelerated to a set starting gear shifting speed, so that the loss when the clutch is combined is reduced, and smooth starting and gear shifting are facilitated; after starting and gear shifting are finished, the engine is controlled to gradually accelerate to the control rotating speed of the crude throttle, and the power gear shifting transmission 1 accelerates along with the control rotating speed, so that the starting and gear shifting process of the vehicle can be stable through combined control of the engine and the transmission, and the vehicle can stably accelerate along with the gentle speed recovery of the engine.

As a preferred embodiment, the throttle control speed of the engine is generally 1000-2200r/min, and the set starting gear shifting speed is 800-900 r/min.

As a preferred embodiment, the set starting shift speed is preferably set to 850 r/min.

In a preferred embodiment, the T1 is preferably 350ms, the T2 is preferably 2.5s, and the T3 is preferably 2.5 s.

A starting and gear shifting control system for a single drum roller, as shown in fig. 3, comprising: controller 3, operating handle 4, sampling unit 5, fender position display unit 6 and hydraulic control device 2, controller 3 respectively with operating handle 4, sampling unit 5, fender

position display unit

6 and 2 electric connection of hydraulic control device, wherein:

the operating handle 4 is used for sending direction, gear shifting, hill starting and oscillation starting signals;

the sampling unit 5 is used for acquiring the current output rotating speed of the engine and the transmission and the inclination angle of the vehicle;

the gear display unit 6 is used for displaying the output gear of the current transmission, the transmission direction of the transmission and diagnostic information;

the controller 3 responds to a starting or gear shifting signal, controls the clutch in the corresponding direction in the transmission to be disconnected with the engine, and controls the rotating speed of the engine to be reduced to a starting gear shifting set speed from the accelerator control rotating speed within T1 time;

the engine speed is controlled to be increased to the throttle control speed in the T3 time, and the transmission speed is increased to the output speed of the set gear along with the increase of the engine speed.

As a preferred embodiment, the hydraulic control device 2 includes a main oil path and at least three branch oil paths communicated with the main oil path, an oil pump 225 is disposed on the main oil path, and the control valve group is disposed on the branch oil paths and used for controlling on-off of the branch oil paths;

As a preferred embodiment, the sampling unit 5 includes an angular velocity sensor disposed on the input shaft and the output shaft of the powershift transmission 1, respectively, and a gradient sensor disposed on the bottom of the powershift transmission 1.

In a preferred embodiment, the gear display unit 6 is used for displaying the output gear, direction and diagnostic information of the current transmission.

The present embodiment also provides a computer-readable storage medium, in which a computer program is stored, and when the computer program is processed and executed, the method for controlling a starting gear shift is implemented.

Further, it should be noted that:

in the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the utility model. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

Although the embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and not to be construed as limiting the present invention, and those skilled in the art can make changes, modifications, substitutions and alterations to the above embodiments without departing from the principle and spirit of the present invention, and any simple modification, equivalent change and modification made to the above embodiments according to the technical spirit of the present invention still fall within the technical scope of the present invention.

Claims

1. A hydraulic control device is characterized by comprising a hydraulic control oil path and a control valve group, wherein the hydraulic control oil path is connected with an oil source and comprises a main oil path and at least three oil distribution paths communicated with the main oil path, an oil pump is arranged on the main oil path, and the control valve group is arranged on the oil distribution paths and used for controlling the on-off of each oil distribution path;

2. The hydraulic control apparatus according to claim 1, wherein a pressure control valve is further provided upstream of the second branch passage, and a downstream of the second branch passage is further communicated with a fourth hydraulic directional control valve and a second hydraulic directional control valve for finely adjusting an oil pressure in an oil passage communicating with the first hydraulic directional control valve, the second hydraulic directional control valve, the third hydraulic directional control valve, and the fourth hydraulic directional control valve.

3. The hydraulic control device according to claim 1, wherein a fourth branch oil passage is connected to the output end of the oil pump, a pressure measuring device is provided at a junction upstream of the fourth branch oil passage, and a main pressure valve is provided on the fourth branch oil passage and is configured to drain off excess oil pressure when the pressure at the junction is too high to limit the pressure, so that the oil pressures of the first branch oil passage, the second branch oil passage, and the third branch oil passage are maintained within a limited pressure range.

4. A hydraulic control arrangement according to claim 3, characterised in that the limiting pressure is in the range 1.3-1.7 MPa.

5. A hydraulic control apparatus according to claim 3, wherein a third throttle valve is provided downstream of the fourth oil dividing passage.

6. A hydraulic control apparatus according to claim 3, wherein a cooler is further provided between the main pressure valve and the third throttle valve of the fourth branch passage.

7. The hydraulic control apparatus according to claim 1, wherein a first check valve and a second check valve are provided in a passage through which the second branch oil passage communicates with the first hydraulic directional control valve and the fourth hydraulic directional control valve, respectively.

8. The hydraulic control apparatus according to claim 1, wherein a first throttle valve and a second throttle valve are provided upstream of the second branch oil passage and the third branch oil passage, respectively.

9. The hydraulic control apparatus of claim 1, wherein the output of the oil pump is further provided with a relief valve.

10. A power shift transmission comprising a housing and a transmission disposed within the housing, wherein the hydraulic control apparatus of any one of claims 1-9 is further disposed within the housing.