WO2022116334A1

WO2022116334A1 - Rear power take-off assembly, engineering vehicle, and control method for engineering vehicle

Info

Publication number: WO2022116334A1
Application number: PCT/CN2020/140743
Authority: WO
Inventors: 马东岭; 崔志勇; 邵磊; 张成国; 范向阳
Original assignee: 潍柴动力股份有限公司
Priority date: 2020-12-01
Filing date: 2020-12-29
Publication date: 2022-06-09
Also published as: CN112594385A

Abstract

A rear power take-off assembly (100), an engineering vehicle (500), and a control method for the engineering vehicle (500). The rear power take-off assembly (100) comprises: a housing (10); a gear shaft (20), the gear shaft (20) being arranged in the housing (10) in a penetrating manner, and the gear shaft (20) being used for being connected to an output end of an engine; an output flange (30), wherein the output flange (30) is sleeved on the gear shaft (20), an accommodating cavity (50) is formed among the housing (10), the output flange (30) and the gear shaft (20), and an air intake hole in communication with the accommodating cavity (50) is provided in the housing (10); and a pneumatic clutch mechanism (40), the pneumatic clutch mechanism (40) being arranged in the accommodating cavity (50), and the pneumatic clutch mechanism (40) being used for controlling the gear shaft (20) and the output flange (30) to be switched between a connected state and a disconnected state.

Description

Rear power take-off assembly, construction vehicle and control method for construction vehicle

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the priority of the Chinese patent application with the application number of 202011387102.5 and the title of "rear power take-off assembly, construction vehicle and control method of construction vehicle" submitted to the State Intellectual Property Office of China on December 01, 2020 and rights, the entire contents of which are incorporated herein by reference.

technical field

The invention belongs to the technical field of engines, and in particular relates to a rear power take-off assembly, an engineering vehicle and a control method for the engineering vehicle.

Background technique

The powder tanker is a general-purpose vehicle for transporting powder materials. The existing powder tanker usually needs to be driven by an engine when it is loaded. In order to save costs, the existing rear power take-off assembly is usually used to drive it. However, because the rear power take-off assembly and the engine crankshaft are directly connected through gears, the rear power take-off assembly outputs power with the rotation of the engine, and the interruption of power output cannot be realized, resulting in the body-mounted air compressor device always in working state, which is difficult to meet the requirements of the whole vehicle. Working demands of driving conditions.

SUMMARY OF THE INVENTION

It is an object of the present invention to at least solve the problem of difficulty in interrupting the power output of the engine to the rear power take-off. This purpose is achieved through the following technical solutions:

A first aspect of the present invention proposes a rear power take-off assembly, the rear power take-off assembly includes:

case;

a gear shaft, the gear shaft is penetrated through the casing, and the gear shaft is used to connect the output end of the engine;

an output flange, the output flange is sleeved on the gear shaft, a accommodating cavity is formed between the casing, the output flange and the gear shaft, and the casing is provided with the accommodating cavity The air inlet hole communicated with the cavity;

A pneumatic clutch mechanism is provided in the accommodating cavity, and the pneumatic clutch mechanism is used to control the gear shaft and the output flange to switch between a connected state and a disconnected state.

According to the rear power take-off assembly of the embodiment of the present invention, the connection or disconnection between the gear shaft and the output flange is controlled by the pneumatic clutch mechanism, so as to realize the interruption of the power output of the engine, effectively control the output power of the engine, and avoid loading air pressure on the body The machine is always in working condition.

In addition, the rear power take-off assembly according to the embodiment of the present invention may also have the following technical features:

In some embodiments of the present invention, the rear power take-off assembly further includes a sealing member, the sealing member is connected to an end of the output flange close to the casing, and the sealing member is along the circumference of the casing. Abutting against the housing, the seal is used for sealing the lubricating oil in the accommodating cavity.

In some embodiments of the present invention, the pneumatic clutch mechanism includes:

Main friction plate, the main friction plate is sleeved on the intermediate shaft in a sliding manner relative to the intermediate shaft, the intermediate shaft is sleeved on the gear shaft, the accommodating cavity is formed in the housing, the between the flange and the intermediate shaft;

Auxiliary friction plate, the auxiliary friction plate is internally connected to the output flange in a slidable manner relative to the output flange, and when the gear shaft and the output flange are in a disconnected state, the main friction plate There is a gap between the plate and the auxiliary friction plate, and when the gear shaft and the output flange are in a connected state, the main friction plate is tightly combined with the auxiliary friction plate;

A push assembly, the push assembly is disposed in the accommodating cavity in a slidable manner relative to the accommodating cavity, and the push assembly can move and push toward the main friction plate and the auxiliary friction plate under the action of gas the main friction plate is combined with the auxiliary friction plate;

a reset piece, the reset piece is arranged on the intermediate shaft, and the reset piece is used to push the push assembly to reset.

In some embodiments of the present invention, the inner edge of the main friction plate is provided with first inner teeth, the outer edge of the intermediate shaft is provided with first outer teeth matched with the first inner teeth, the auxiliary The outer edge of the friction plate is provided with second outer teeth, and the output flange is provided with second inner teeth matched with the second outer teeth.

In some embodiments of the present invention, both the main friction plates and the auxiliary friction plates are plural, and the main friction plates and the auxiliary friction plates are arranged at intervals.

In some embodiments of the present invention, the push assembly includes:

A piston, an intake port is formed on the housing, the intake port communicates with the accommodating cavity, a groove is provided at one end of the piston close to the intake port, and the piston is far from the intake port. One end is provided with a first limit block and a second limit block;

a piston bearing, which is sleeved on the first limit block;

A push block, the push block is sleeved on the piston bearing, and one end of the push block close to the main friction plate is provided with a blocking arm, and the blocking arm is used to contact the main friction plate or the auxiliary friction plate, so The push block is provided with a guide groove for guiding the reset piece;

A push bearing is sleeved on the push block, and the push bearing is clamped between the second limit block and the push block along the radial direction of the gear shaft.

A second aspect of the present invention provides an engineering vehicle, the engineering vehicle comprising:

engine;

a rear power take-off assembly, the rear power take-off assembly is used to connect the output end of the engine;

an air supply system, the air supply system is used to provide air for the rear power take-off assembly;

an ECU, the ECU is respectively electrically connected to the engine and the rear power take-off assembly, and the ECU controls the rear power take-off assembly to be connected to the engine through the air supply system.

According to the construction vehicle of the embodiment of the present invention, the vehicle speed and the engine speed are obtained through the ECU. If the vehicle speed is 0 and the engine speed is greater than 0, the ECU controls the air supply system to supply air to the rear power take-off assembly, so that the gear shaft is connected with the output flange , the ECU controls the air supply system to stop supplying air to the rear power take-off assembly according to the information such as engine flameout, so as to disconnect the gear shaft from the output flange. Thereby, the output power of the engine is effectively controlled, and the body-mounted air compressor device is prevented from working all the time.

A third aspect of the present invention provides a control method for an engineering vehicle. The control method is used to control the engineering vehicle according to any one of the above embodiments. The control method includes:

S1: Get the speed of the vehicle;

S2: Get the engine speed;

S3: Get the running state of the engine;

S4: Get the status of the solenoid valve;

S5: According to the vehicle speed equal to 0, the engine speed greater than 0, the engine running state is normal and the solenoid valve running state is normal, obtain the opening signal of the PTO activation switch;

S6: control the engine speed to be not less than the first speed threshold and not greater than the second speed threshold;

S7: Obtain the opening signal of the PTO safety switch, and control the air supply system to supply air to the rear power take-off assembly.

According to the control method of the construction vehicle according to the embodiment of the present invention, the ECU judges that the vehicle is in a stopped state according to the vehicle speed being 0, and judges that the engine is in a running state according to the engine speed being greater than 0. At this time, the ECU controls the speed of the engine to be within the first threshold range, In order to prevent the output flange from being damaged because the gear shaft rotates too fast when the gear shaft is connected with the output flange.

In addition, the control method for the construction vehicle according to the embodiment of the present invention may also have the following technical features:

In some embodiments of the present invention, after controlling the air supply system to supply air to the rear power take-off assembly according to the engine speed not being greater than the third speed threshold value, the following steps are further included:

Obtain the air pressure value of the rear power take-off assembly;

According to the air pressure value of the rear power take-off assembly being greater than the air pressure threshold, the engine speed is controlled to be less than the second speed threshold.

In some embodiments of the present invention, the second rotational speed threshold is smaller than the third rotational speed threshold.

Description of drawings

Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The drawings are for the purpose of illustrating preferred embodiments only and are not to be considered limiting of the invention. Also, the same components are denoted by the same reference numerals throughout the drawings. In the attached image:

1 is a schematic diagram of the overall structure of an embodiment of an engineering vehicle of the present invention;

Figure 2 is a cross-sectional view of the overall structure of the rear power take-off assembly shown in Figure 1;

Fig. 3 is a partial enlarged view A shown in Fig. 2;

Figure 4 is a schematic exploded schematic diagram of the partial structure of the rear power take-off assembly shown in Figure 2;

FIG. 5 is a control flow chart of the construction vehicle control method of the present invention.

The symbols in the accompanying drawings are indicated as follows:

100: Rear power take-off assembly;

10: shell, 11: intake port;

20: gear shaft, 21: intermediate shaft, 211: first external tooth;

30: output flange;

40: Pneumatic clutch mechanism, 41: Main friction plate, 411: First inner tooth, 42: Auxiliary friction plate, 421: Second outer tooth, 43: Push component, 431: Piston, 4311: Groove, 4312: First Limit block, 4313: Second limit block, 432: Piston bearing, 4321: Stop arm, 433: Push block, 4331: Guide groove, 44: Reset piece, 441: Guide sleeve, 45: Locating bearing, 46: Stop Plate, 47: Limit ring, 48: Limit bearing;

50: accommodating cavity;

60: seal, 61: fastener;

200: engine;

300: Air supply system, 301: Solenoid valve, 302: Air supply pipeline;

400: ECU;

500: Construction vehicles.

Detailed ways

Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be embodied in various forms and should not be limited by the embodiments set forth herein. Rather, these embodiments are provided so that the present disclosure will be more thoroughly understood, and will fully convey the scope of the present disclosure to those skilled in the art.

It is to be understood that the terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting. As used herein, the singular forms "a," "an," and "the" can also be intended to include the plural forms unless the context clearly dictates otherwise. The terms "comprising", "comprising", "containing" and "having" are inclusive and thus indicate the presence of stated features, steps, operations, elements and/or components, but do not preclude the presence or addition of one or Various other features, steps, operations, elements, components, and/or combinations thereof.

Although the terms first, second, third, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be restricted by these terms. These terms may only be used to distinguish one element, component, region, layer or section from a second region, layer or section. Terms such as "first," "second," and other numerical terms when used herein do not imply a sequence or order unless clearly indicated by the context. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of example embodiments.

For ease of description, spatially relative terms such as "inner", "outer", "inner" may be used to describe the relationship of one element or feature relative to a second element or feature as shown in the figures. ", "outside", "below", "below", "above", "above", etc. This spatially relative term is intended to include different orientations of the device in use or operation other than the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as "below" or "beneath" other elements or features would then be oriented "above" or "above the other elements or features" above features". Thus, the example term "below" can encompass both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

As shown in FIGS. 1 to 3 , an embodiment of the first aspect of the present invention provides a rear power take-off assembly 100 . The rear power take-off assembly 100 includes: a casing 10 , a gear shaft 20 , an output flange 30 and a pneumatic The clutch mechanism 40 , specifically, the gear shaft 20 is passed through the casing 10 , the gear shaft 20 is used for connecting the output end of the engine, the output flange 30 is sleeved on the gear shaft 20 , the casing 10 , the output flange 30 and the gear shaft 20 A accommodating cavity 50 is formed therebetween, the housing 10 is provided with an air intake hole communicating with the accommodating cavity 50 , the pneumatic clutch mechanism 40 is arranged in the accommodating cavity 50 , and the pneumatic clutch mechanism 40 is used to control the gear shaft 20 and the output flange 30 Toggle between connected and disconnected states.

According to the rear power take-off assembly 100 of the embodiment of the present invention, the connection or disconnection between the gear shaft 20 and the output flange 30 is controlled by the pneumatic clutch mechanism 40, so as to realize the interruption of the power output of the engine and effectively control the output power of the engine, Avoid the bodywork air compressor unit being in working condition all the time.

In some embodiments of the present invention, the rear power take-off assembly 100 further includes a sealing member 60, and the sealing member 60 is connected to the end of the output flange 30 close to the housing 10 through fasteners (eg, bolts) 61. Specifically, the sealing member 60 is sealed The member 60 is an annular member, the sealing member 60 abuts against the outer side of the casing 10 along the circumferential direction of the casing 10 , the sealing member 60 is located at the joint of the output flange 30 and the casing 10 , and the sealing member 60 can prevent Lubricating oil leaks. When the output flange 30 is connected to the gear shaft 20, the gear shaft 20 drives the output flange 30 to rotate, and the output flange 30 drives the seal 60 to rotate. At this time, the housing 10 remains stationary, and the seal 60 is opposite to the housing 10 turns.

In some embodiments of the present invention, as shown in FIG. 3 , the pneumatic clutch mechanism 40 includes: a main friction plate 41 , an auxiliary friction plate 42 , a pushing component 43 and a reset member 44 . Specifically, the main friction plate 41 can be relatively middle The shaft 21 is sleeved on the intermediate shaft 21 in a sliding manner. The intermediate shaft 21 is connected to the gear shaft 20 through its internal teeth and the external teeth of the gear shaft 20 . The auxiliary friction plate 42 is internally connected to the output flange 30 in a slidable manner relative to the output flange 30. When the gear shaft 20 and the output flange 30 are in a disconnected state, there is a gap between the main friction plate 41 and the auxiliary friction plate 42. , when the gear shaft 20 and the output flange 30 are in a connected state, the main friction plate 41 and the auxiliary friction plate 42 are tightly combined. The connection or disconnection between the gear shaft 20 and the output flange 30 is realized by the cooperation between the main friction plate 41 and the auxiliary friction plate 42 . The accommodating cavity 50 is formed between the housing 10 , the output flange 30 and the intermediate shaft 21 , the pushing assembly 43 is disposed in the accommodating cavity 50 in a slidable manner relative to the accommodating cavity 50 , in addition, the reset member 44 is disposed on the intermediate shaft 21 . In the embodiment of the present invention, the accommodating cavity 50 on the side of the push assembly 43 close to the main friction plate 41 is filled with lubricating oil to ensure the lubrication between the main friction plate 41 and the auxiliary friction plate 42 and avoid the main friction plate 41 and the auxiliary friction plate. Abnormal noise occurs when the sheet 42 contacts.

The working principle of the pneumatic clutch mechanism 40: the push component 43 can move to the main friction plate 41 and the auxiliary friction plate 42 under the action of the gas and push the main friction plate 41 and the auxiliary friction plate 42 to combine, that is, the gas is moved away from the output flange 30. One end enters the accommodating cavity 50, and makes the push assembly 43 move in the direction of the main friction plate 41 and the auxiliary friction plate 42. As more and more gas enters the accommodating cavity 50, the push assembly 43 contacts the main friction plate 41 or the auxiliary friction plate 42. plate 42 and pushes the main friction plate 41 to be tightly combined with the auxiliary friction plate 42 , thereby ensuring the driving connection between the gear shaft 20 and the output flange 30 . When the output power of the engine 200 is no longer required, the air supplied to the accommodating chamber 50 is exhausted, and the push assembly 43 moves away from the main friction plate 41 and the auxiliary friction plate 42 through the action of the reset member 44 provided on the intermediate shaft 42, Until the push assembly 43 is reset, the main friction plate 41 and the auxiliary friction plate 42 are reset.

Specifically, when the reset member 44 is in the original state, one end of the reset member 44 is disposed in the groove 211 of the intermediate shaft 21 , the other end of the reset member 44 is located at the outer end of the intermediate shaft 21 , and the other end of the reset member 44 is on the A guide sleeve 441 is provided, and the guide sleeve 441 is used to guide the reset member 44 . The reset member 44 is a spring.

In some embodiments of the present invention, as shown in FIG. 4 , the inner edge of the main friction plate 41 is provided with first inner teeth 411 , and the outer edge of the intermediate shaft 21 is provided with first outer teeth matched with the first inner teeth 411 211 , the main friction plate 41 and the intermediate shaft 21 are slidably connected through the cooperation of the first inner teeth 411 and the first outer teeth 211 , while ensuring that the main friction plate 41 and the intermediate shaft 21 do not move along the radial direction of the main friction plate 41 . The outer edge of the auxiliary friction plate 42 is provided with a second outer tooth 421 , the output flange 30 is provided with a second inner tooth matched with the second outer tooth 421 , and the auxiliary friction plate 41 and the output flange 30 pass through the second outer tooth 421 A sliding connection is achieved with the second inner teeth, and at the same time, it is ensured that the auxiliary friction plate 42 and the output flange 30 do not have positions along the radial direction of the auxiliary friction plate 42 .

In some embodiments of the present invention, there are multiple main friction plates 41 and multiple auxiliary friction plates 42 , and multiple main friction plates 41 and multiple auxiliary friction plates 42 are provided with multiple main friction plates 41 and multiple auxiliary friction plates at intervals. 42 are arranged at intervals to increase the contact area between the main friction plate 41 and the auxiliary friction plate 42 , thereby improving the tightness of the combination of the main friction plate 41 and the auxiliary friction plate 42 .

In some embodiments of the present invention, the push assembly 43 includes: a piston 431 , a piston bearing 432 , a push block 433 and a push bearing 434 . Specifically, the housing 10 is formed with an air inlet 11 , the air inlet 11 and the accommodating cavity 50 is connected, one end of the piston 431 close to the intake port 11 is provided with a groove 4311 , and the air supply system 300 supplies gas through the intake port 11 like the accommodating cavity 50 to push the piston 431 to move in the direction of the main friction plate 41 . One end of the piston 431 away from the intake passage 11 is provided with a first limiting block 4312 , the piston bearing 432 is sleeved on the first limiting block 4312 , and the radial direction of the piston 431 is limited by the piston bearing 432 . The push block 433 is sleeved on the piston bearing 432 , the push bearing 434 is sleeved on the push block 433 , and the push bearing 434 is clamped between the second limit block 4313 and the push block 433 along the radial direction of the gear shaft 20 . The push block 433 is limited in the radial direction of the intermediate shaft 21 . One end of the push block 433 close to the main friction plate 41 is provided with a blocking arm 4321. The blocking arm 4321 is used to contact the main friction plate 41 or the auxiliary friction plate 42. When the gas pushes the piston 431 to move to the main friction plate 41, the piston 431 drives the blocking arm 4321 move to the main friction plate 41 together, and the blocking arm 4321 pushes the main friction plate 41 to contact and combine with the auxiliary friction plate 42 . The lower end of the push block 433 is provided with a guide groove 4331 for guiding the reset member 44 , and the reset member 44 is guided by the cooperation of the guide sleeve 441 and the guide groove 4331 .

In some embodiments of the present invention, the intermediate shaft 21 and the gear shaft 20 are connected through the cooperation of internal teeth and external teeth. The rear power take-off assembly 40 also includes a positioning bearing 45, which is arranged between the housing 10 and the gear shaft 20, and the intermediate shaft 21 is opened between the positioning bearing 45 and the output flange 30, so as to position the intermediate shaft 21 , to prevent the intermediate shaft 21 from sliding along the gear shaft 20 .

In some embodiments of the present invention, the rear power take-off assembly 40 further includes a baffle 46 , the baffle 46 is an annular baffle, the annular baffle 46 is sleeved on the gear shaft 20 , and the baffle 46 is arranged inside the output flange 30 , the baffle 46 is located between the intermediate shaft 21 and the output flange 30 along the axial direction of the gear shaft 20, the limit ring 47 and the limit bearing 48 are sleeved on the gear shaft 21, and the output flange 30 is sleeved on the limit bearing 48. The output flange 30 restricts the limit bearing 48 from moving away from the push assembly 40. Both sides of the limit ring 47 are in contact with the limit bearing 48 and the baffle 46 respectively, and the two ends of the intermediate shaft 21 are respectively in contact with the positioning bearing 45. Abutting against the baffle 46 , that is, the intermediate shaft 21 is positioned through the cooperation of the positioning bearing 45 , the baffle 46 , the limiting ring 47 and the limiting bearing 48 . The baffle plate 46 is also used to limit the position of the intermediate shaft 21 along the axial direction of the gear shaft 20 and the positions of the main friction plate 41 and the auxiliary friction plate 42, so as to prevent the main friction plate 41 and the auxiliary friction plate 42 from contacting the output flange 40, and to avoid contact with the output flange 40. The output flange 40 causes wear. In addition, in the embodiment of the present invention, sealing rings are provided between the intermediate shaft 21 and the baffle plate 46 and between the piston 431 and the housing 10 to prevent the leakage of lubricating oil or gas.

An embodiment of the second aspect of the present invention proposes an engineering vehicle 500 . The engineering vehicle 500 includes an engine 200 , a rear power take-off assembly 100 , an air supply system 300 and an ECU 400 , and the rear power take-off assembly 100 is used to connect the engine 200 . At the output end, the air supply system 300 is used to provide gas for the rear power take-off assembly 100. The ECU 400 is electrically connected to the engine 200 and the rear power take-off assembly 100 respectively. The ECU 400 controls the rear power take-off assembly 100 and the engine 200 through the air supply system 300. connect.

According to the construction vehicle 500 of the embodiment of the present invention, the vehicle speed and the engine speed are obtained through the ECU 400. If the vehicle speed is 0, the engine speed is greater than 0, the engine is running normally, and the solenoid valve is not faulty, the ECU 400 controls the air supply system 300 to be the rear power take-off assembly 100 Air is supplied to connect the gear shaft 20 with the output flange 30 , and the ECU 400 controls the air supply system 300 to stop supplying air to the rear power take-off assembly 100 according to information such as engine shutdown, so as to disconnect the gear shaft 20 from the output flange 300 . Thereby, the output power of the engine is effectively controlled, and the body-mounted air compressor device is prevented from working all the time.

In some embodiments of the present invention, the rear power take-off assembly 100 further includes a PTO activation switch (not shown in the figure), a PTO safety switch, a PTO switch+ and a PTO switch-, wherein the PTO activation switch is a part of the solenoid valve 302 . Activation switch, PTO safety switch is the activation switch of the rear power take-off assembly, PTO switch + is the control switch for engine speed up, PTO switch - is the control switch for engine deceleration. The air supply system 300 further includes a solenoid valve 301 , the solenoid valve 301 is arranged on the air supply pipeline 302 , and the solenoid valve 302 is electrically connected to the ECU 400 .

As shown in FIG. 5 , an embodiment of the third aspect of the present invention provides a control method for an engineering vehicle. The control method is used to control the engineering vehicle according to any of the above embodiments, and the control method includes the following steps:

S1: Get the speed of the vehicle;

S2: Get the engine speed;

S3: Get the running state of the engine;

S4: Get the status of the solenoid valve;

Specifically, the ECU obtains the turn-on signal of the PTO (power take off) activation switch according to the vehicle speed equal to 0 (that is, the construction vehicle is in a stopped state), the engine speed is greater than 0, the engine running state is normal and the solenoid valve running state is normal, After the PTO activation switch is turned on, the solenoid valve can be connected. The ECU controls the engine speed to be not less than the first speed threshold and not greater than the second speed threshold according to the turn-on signal of the PTO activation switch. When the engine speed is between the first speed threshold and the second speed threshold, the rear power take-off assembly will not be The speed is too fast to engage or cause some damage after engagement. The ECU obtains the opening signal of the PTO safety signal according to the engine speed not less than the first speed threshold and not greater than the second speed threshold. After the PTO safety signal is turned on, the solenoid valve can be opened, and then the ECU controls the solenoid valve of the air supply system to open to Let the gas enter the rear power take-off assembly, and then control the combination of the gear shaft and the output flange.

According to the control method of the construction vehicle according to the embodiment of the present invention, the ECU obtains the turn-on signal of the PTO activation switch according to the information that the vehicle speed is 0, the engine speed is greater than 0, the engine running state is normal, and the solenoid valve has no fault, and then the ECU controls the engine speed to not be When it is less than the first rotational speed threshold and not greater than the second rotational speed threshold, the solenoid valve is controlled to be connected, so that the air supply system supplies air to the rear power take-off assembly.

In some embodiments of the present invention, the following steps are also included after S7:

S71: Obtain the air pressure value of the rear power take-off assembly;

S72: Control the engine speed to be less than the third speed threshold according to the air pressure value of the rear power take-off assembly being greater than the air pressure threshold.

According to the pressure in the receiving chamber of the rear power take-off assembly is greater than the air pressure threshold, it is judged that the main friction plate and the auxiliary friction plate are in close contact. At this time, the engine speed is controlled according to the power demand of the output power mechanism, but the engine speed should be less than or equal to the third speed Threshold, the third speed threshold is the maximum speed threshold that the rear power take-off assembly can bear, so as to prevent the pneumatic clutch mechanism from being damaged due to excessive engine speed.

In some embodiments of the invention, the second rotational speed threshold is smaller than the third rotational speed threshold.

The second rotational speed threshold is the speed at which the rear power take-off assembly transitions from the disconnected state to the connected state. At this time, a lower speed is required to prevent damage to the rear power take-off assembly caused by increasing the speed. When the air pressure of the rear power take-off assembly is greater than the air pressure threshold, the pneumatic clutch mechanism is closely combined. At this time, the engine speed can be increased according to the demand of power output. Therefore, the third speed threshold is when the pneumatic clutch mechanism is tightly coupled, the pneumatic clutch mechanism can withstand the maximum speed.

Get the off signal of the PTO safety switch;

Get the close signal of the PTO activation switch;

Get the engine flameout signal;

The solenoid valve is controlled to be disconnected according to the shutdown signal of the PTO safety fire, the shutdown signal of the PTO activation switch or the engine shutdown signal.

When the PTO safety switch is turned off, the PTO activation switch is turned off or the engine is turned off, the solenoid valve should be disconnected to disconnect the rear power take-off assembly, thereby controlling the output flange to stop rotating.

In some embodiments of the present invention, S6 and S72 further comprise the following steps:

Get the open signal of PTO switch +;

Control the engine speed to increase.

Get the open signal of the PTO switch-;

Control the engine speed to decrease.

In some embodiments of the invention, neither the PTO switch+ nor the PTO switch- signals are deactivated when the signal of the PTO activation switch is OFF.

The above are only preferred specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art who is familiar with the technical scope disclosed by the present invention can easily think of changes or substitutions, All should be included within the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claims.

Claims

A rear power take-off assembly, characterized in that the rear power take-off assembly comprises:

case;

a gear shaft, the gear shaft is penetrated through the casing, and the gear shaft is used to connect the output end of the engine;

an output flange, the output flange is sleeved on the gear shaft, a accommodating cavity is formed between the casing, the output flange and the gear shaft, and the casing is provided with the accommodating cavity The air inlet hole communicated with the cavity;

A pneumatic clutch mechanism is provided in the accommodating cavity, and the pneumatic clutch mechanism is used to control the gear shaft and the output flange to switch between a connected state and a disconnected state.
The rear power take-off assembly according to claim 1, wherein the rear power take-off assembly further comprises a sealing member, the sealing member is connected to an end of the output flange close to the housing, the The sealing member abuts against the housing along the circumferential direction of the housing, and the sealing member is used for sealing the lubricating oil in the accommodating cavity.
The rear power take-off assembly according to claim 1 or 2, wherein the pneumatic clutch mechanism comprises:

Main friction plate, the main friction plate is sleeved on the intermediate shaft in a sliding manner relative to the intermediate shaft, the intermediate shaft is sleeved on the gear shaft, the accommodating cavity is formed in the housing, the between the flange and the intermediate shaft;

Auxiliary friction plate, the auxiliary friction plate is internally connected to the output flange in a slidable manner relative to the output flange, and when the gear shaft and the output flange are in a disconnected state, the main friction plate There is a gap between the plate and the auxiliary friction plate, and when the gear shaft and the output flange are in a connected state, the main friction plate is tightly combined with the auxiliary friction plate;

A push assembly, the push assembly is disposed in the accommodating cavity in a slidable manner relative to the accommodating cavity, and the push assembly can move and push toward the main friction plate and the auxiliary friction plate under the action of gas the main friction plate is combined with the auxiliary friction plate;

a reset piece, the reset piece is arranged on the intermediate shaft, and the reset piece is used to push the push assembly to reset.
The rear power take-off assembly according to claim 3, wherein the inner edge of the main friction plate is provided with a first inner tooth, and the outer edge of the intermediate shaft is provided with a first inner tooth. A first external tooth, the outer edge of the auxiliary friction plate is provided with a second external tooth, and the output flange is provided with a second internal tooth matched with the second external tooth.
The rear power take-off assembly according to claim 3, wherein there are multiple main friction plates and the auxiliary friction plates, and the plurality of main friction plates and the plurality of auxiliary friction plates are arranged at intervals.
The rear power take-off assembly according to claim 3, wherein the pushing assembly comprises:

A piston, an intake port is formed on the housing, the intake port communicates with the accommodating cavity, a groove is provided at one end of the piston close to the intake port, and the piston is far from the intake port. One end is provided with a first limit block and a second limit block;

a piston bearing, which is sleeved on the first limit block;

A push block, the push block is sleeved on the piston bearing, and the end of the push block close to the main friction plate is provided with a blocking arm, and the blocking arm is used to contact the main friction plate or the auxiliary friction plate, so The push block is provided with a guide groove for guiding the reset piece;

A push bearing is sleeved on the push block, and the push bearing is clamped between the second limit block and the push block along the radial direction of the gear shaft.
An engineering vehicle, characterized in that the engineering vehicle comprises:

engine;

a rear power take-off assembly, the rear power take-off assembly is used to connect the output end of the engine, and the rear power take-off assembly is the rear power take-off assembly according to any one of claims 1 to 6;

an air supply system, the air supply system is used to provide air for the rear power take-off assembly;

The ECU is electrically connected to the engine and the rear power take-off assembly, respectively, and the ECU controls the rear power take-off assembly to be connected to the engine through the air supply system.
A control method for an engineering vehicle, the control method is used to control the engineering vehicle according to claim 7, wherein the control method comprises:

get the speed;

Get the engine speed;

Get the running state of the engine;

Get the status of the solenoid valve;

According to the vehicle speed equal to 0, the engine speed greater than 0, the normal operating state of the engine and the normal operating state of the solenoid valve, the turn-on signal of the PTO activation switch is obtained;

controlling the engine speed to be not less than the first speed threshold and not greater than the second speed threshold;

Obtain the open signal of the PTO safety switch, and control the air supply system to supply air to the rear power take-off assembly.
The control method for a construction vehicle according to claim 8, wherein the control of the air supply system to supply air to the rear power take-off assembly according to the engine speed not greater than the first speed threshold value further comprises the following steps:

Obtain the air pressure value of the rear power take-off assembly;

According to the air pressure value of the rear power take-off assembly being greater than the air pressure threshold, the engine speed is controlled to be less than the third speed threshold.
The control method of an engineering vehicle according to claim 9, wherein the second rotational speed threshold is smaller than the third rotational speed threshold.