CN220147143U

CN220147143U - Hydraulic mechanical comprehensive transmission device of crawler fire truck

Info

Publication number: CN220147143U
Application number: CN202321030612.6U
Authority: CN
Inventors: 张硕荦; 武彦斌; 高淑芳; 陈钰冉; 宋博威; 张珂
Original assignee: Chongxing Technology Co ltd; Hebei Juntan Technology Co ltd
Current assignee: Chongxing Technology Co ltd; Hebei Juntan Technology Co ltd
Priority date: 2023-05-04
Filing date: 2023-05-04
Publication date: 2023-12-08
Anticipated expiration: 2033-05-04

Abstract

The utility model discloses a hydraulic mechanical comprehensive transmission device of a crawler fire truck, which comprises a hydraulic torque converter, a hydraulic system, a speed changing system and a steering system, wherein the hydraulic torque converter is arranged at one end of the comprehensive transmission device, the hydraulic system is used for outputting power, the speed changing system is used for adjusting the advancing speed of the crawler fire truck, the steering system is used for controlling the advancing direction of the crawler fire truck, the hydraulic system is positioned at the output end of the hydraulic torque converter, the speed changing system is arranged at one side of the hydraulic system far away from the hydraulic torque converter, and the steering system is arranged at one side of the speed changing system far away from the hydraulic system.

Description

Hydraulic mechanical comprehensive transmission device of crawler fire truck

Technical Field

The utility model relates to the technical field of tracked vehicle transmission, in particular to a hydraulic mechanical comprehensive transmission device of a tracked fire truck.

Background

In the prior art, the development of the crawler fire-fighting vehicles in China is rapid, most crawler fire-fighting vehicles are reformed by armored vehicles at present, the structure is that an engine is transmitted to driving wheels at two sides through a gearbox and a planetary steering machine, a braking belt is arranged on the planetary steering machine, the left steering machine and the right steering machine are braked by pushing and pulling an operating rod to generate differential speed, steering is realized, the crawler fire-fighting vehicles are used as driving devices of the crawler vehicles and are divided into two types, the first type is generally characterized in that engine power is transmitted to the driving wheels of the crawler vehicles by a fixed-shaft gearbox according to a plurality of fixed transmission ratios to drive the crawler vehicles to rotate, and the steering of the crawler vehicles is generally realized by braking one side crawler or reducing the rotation speed of one side crawler. The second type integrates steering, speed changing and the like to form double-power-flow comprehensive transmission, and consists of a direct-drive power transmission path, a steering power transmission path and an auxiliary output power transmission path, wherein the direct-drive power transmission path transmits power of an internal combustion engine to an input shaft of a speed changing mechanism through a hydraulic torque converter, and after the speed change according to the current gear, the power is output from an output shaft of the speed changing mechanism to a bus gear ring and is transmitted to left and right driving wheels through a bus frame; the steering power transmission path drives a busbar sun gear through the power of the internal combustion engine and is transmitted to the left driving wheel and the right driving wheel through a busbar frame; the auxiliary output power transmission path transmits the power of the internal combustion engine to an output device such as a fan drive. The existing crawler fire-fighting truck is mainly formed by refitting armored vehicles, the transmission system is a structure of a mechanical gearbox and a steering machine, the structure cannot achieve a central steering function, is not easy to control, has poor maneuverability, cannot respond quickly if disaster occurs, has no central steering function, cannot meet the driving requirement of complex road conditions, is relatively backward, is not flexible to operate manually, and increases the physical power consumption of a driver.

The application number is: 201810796940.4 discloses a hydromechanical integrated transmission with parallel input and output axes, comprising: four spiral bevel gears, thirty-two straight gears, five main transmission shafts, five planetary rows, four brakes, four clutches, four hydraulic elements, an axial plunger conjuncted pump motor, six hydraulic pumps and four output ends. However, the hydraulic mechanical comprehensive transmission device with parallel input and output axes cannot realize a central steering function, is not easy to control, has relatively poor maneuverability, is not suitable for a crawler fire truck, cannot quickly respond if a disaster occurs, cannot meet the driving requirement of complex road conditions, has no central steering function, has a relatively backward control system, is not flexible to manually control, and increases the physical power consumption of a driver.

Disclosure of Invention

The utility model aims to provide a hydraulic mechanical comprehensive transmission device of a crawler fire truck.

In order to achieve the above purpose, the technical scheme provided by the utility model is as follows:

the hydraulic mechanical comprehensive transmission device of the crawler fire truck comprises a hydraulic torque converter, a hydraulic system for outputting power, a speed changing system for adjusting the traveling speed of the crawler fire truck and a steering system for controlling the traveling direction of the crawler fire truck, wherein the hydraulic system is positioned at the output end of the hydraulic torque converter, the speed changing system is arranged on one side, far away from the hydraulic torque converter, of the hydraulic system, and the steering system is arranged on one side, far away from the hydraulic system, of the speed changing system.

The hydraulic system comprises an oil supply pump, a first straight gear, a second straight gear, a third straight gear and a fourth straight gear, wherein the oil supply pump is configured on one side of the hydraulic torque converter and is arranged at intervals with the hydraulic torque converter, the first straight gear and the second straight gear are arranged at the input end of the hydraulic torque converter and are connected with an engine of the crawler fire truck, the third straight gear and the fourth straight gear are arranged at the input end of the oil supply pump and are connected with the engine of the crawler fire truck, and the first straight gear, the second straight gear, the third straight gear and the fourth straight gear are connected with the engine of the crawler fire truck through a fifth shaft.

The hydraulic torque converter further comprises a fifth straight gear and a sixth straight gear, wherein the fifth straight gear and the sixth straight gear are arranged at the output end of the hydraulic torque converter.

The speed change system comprises a first shaft, a second shaft, a first planetary row and a second planetary row, wherein the first shaft is arranged at the output end of the hydraulic torque converter and is connected with the output end of the hydraulic torque converter through an input assembly, the second shaft is parallel to the first shaft, and the first planetary row and the second planetary row are symmetrically arranged at two ends of the second shaft.

The input assembly comprises an input shaft, a seventh bevel gear and an eighth bevel gear, wherein the input shaft is arranged between the first shaft and the sixth straight gear, one end of the input shaft is fixedly connected with the sixth straight gear, the seventh bevel gear is arranged at one end, far away from the sixth straight gear, of the input shaft, and the eighth bevel gear is arranged at the middle part of the first shaft and meshed with the seventh bevel gear.

The clutch is characterized by further comprising a first gear clutch, a reverse gear clutch, a second gear clutch, a third gear clutch and a fourth gear clutch, wherein the first gear clutch, the reverse gear clutch, the second gear clutch, the third gear clutch and the fourth gear clutch are arranged on the first shaft in parallel and at intervals.

The gear transmission mechanism further comprises a first gear set, a reverse gear set, a second gear set, a third gear set and a fourth gear set, wherein the first gear set is composed of a ninth straight gear and a nineteenth straight gear which are respectively arranged on the first shaft and the second shaft, the ninth straight gear is meshed with the nineteenth straight gear, the reverse gear set is composed of a tenth straight gear and a twenty-second gear which are respectively arranged on the first shaft and the second shaft, the tenth straight gear is meshed with the twenty-second straight gear through a seventeenth straight gear, the second gear set is composed of a fourteenth straight gear and a twenty-first straight gear which are respectively arranged on the first shaft and the second shaft, the fourteenth straight gear is meshed with the twenty-first straight gear, the third gear set is composed of a fifteenth straight gear and a twenty-second straight gear which are respectively arranged on the first shaft and the second shaft, the fifteenth straight gear is meshed with the twenty-second gear, and the fourth gear is composed of a sixteenth straight gear and a sixteenth straight gear which are respectively arranged on the first shaft and the second shaft, and the twenty-second gear is meshed with the twenty-second straight gear.

The gear box further comprises an eighteenth speed change gear and a twenty-fourth speed change gear, and the eighteenth speed change gear and the twenty-fourth speed change gear are symmetrically arranged at two ends of the second shaft.

The steering system comprises a steering pump, a zero shaft and a steering motor, wherein the input end of the steering pump is connected with the first shaft through an eleventh straight gear, a twelfth straight gear and a thirteenth straight gear, the zero shaft and the second shaft are arranged in parallel, a thirty-first straight gear is arranged in the middle of the zero shaft, the input end of the steering motor is meshed with the thirty-first straight gear through a thirty-second straight gear and a thirty-first straight gear, a twenty-seventh straight gear and a twenty-ninth straight gear are symmetrically arranged at two ends of the zero shaft, and the twenty-seventh straight gear and the twenty-ninth straight gear are meshed with the corresponding first planetary row and the second planetary row through idler gears.

The idler gears include a twenty-fifth idler gear, a twenty-sixth idler gear, and a twenty-eighth idler gear, the twenty-fifth idler gear and the twenty-sixth idler gear being disposed between the first planet row and the twenty-seventh spur gear, the twenty-eighth idler gear being disposed between the second planet row and the twenty-ninth spur gear.

The beneficial effects of the utility model are as follows:

the hydraulic system, the speed changing system and the steering system are matched to form a hydraulic transmission and hydrostatic transmission composite device, so that the hydraulic transmission and hydrostatic transmission composite device has good maneuvering performance, the response time of the fire truck for treating various emergencies can be effectively shortened, property loss is reduced, the control is easy, the center steering can be realized, the fire truck can cope with various emergencies in complex and changeable forest road conditions, electrohydraulic manual gear shifting is adopted, the control is easy, and the load of a driver is lightened.

Drawings

FIG. 1 is a schematic diagram of the connection of the components of the present utility model.

In the figure: 1. a first straight gear; 2. a second spur gear; 3. a third spur gear; 4. a fourth spur gear; 5. a fifth spur gear; 6. a sixth spur gear; 7. a seventh bevel gear; 8. an eighth bevel gear; 9. a ninth spur gear; 10. a tenth spur gear; 11. an eleventh spur gear; 12. a twelfth spur gear; 13. a thirteenth spur gear; 14. a fourteenth spur gear; 15. a fifteenth spur gear; 16. sixteenth spur gear; 17. seventeenth straight gear; 18. eighteenth speed change gear; 19. nineteenth spur gear; 20. a twenty-fifth spur gear; 21. a twenty-first straight gear; 22. a twenty-second spur gear; 23. a twenty-third spur gear; 24. a twenty-fourth speed change gear; 25. a twenty-fifth idler; 26. a twenty-sixth idler; 27. a twenty-seventh spur gear; 28. a twenty-eighth idler; 29. a twenty-ninth spur gear; 30. a thirty-first spur gear; 31. a thirty-first straight gear; 32. a thirty-second spur gear; TC, torque converter; p1, an oil supply pump; i, a first shaft; II, a second shaft; III, zero axis; IV, an input shaft; v, a fifth shaft; PGS1, first row of satellites; PGS2, second planet row; c1, a first gear clutch; c2, a reverse clutch; c3, a second gear clutch; c4, a three-gear clutch; c5, a fourth gear clutch; PM, steering pump; p2, steering motor.

Detailed Description

The utility model is described in further detail below with reference to the accompanying drawings,

the utility model discloses a hydraulic mechanical comprehensive transmission device of a crawler fire truck, which comprises a hydraulic torque converter TC, a hydraulic system for outputting power, a speed changing system for adjusting the travelling speed of the crawler fire truck and a steering system for controlling the travelling direction of the crawler fire truck, wherein the hydraulic torque converter TC is arranged at the output end of the hydraulic torque converter TC, the speed changing system is arranged at one side of the hydraulic system far away from the hydraulic torque converter TC, the steering system is arranged at one side of the speed changing system far away from the hydraulic system, and the connection relation schematic diagram of all components of the hydraulic mechanical comprehensive transmission device is shown in figure 1.

The hydraulic system comprises an oil supply pump P1, a first spur gear 1, a second spur gear 2, a third spur gear 3 and a fourth spur gear 4, wherein the oil supply pump P1 is arranged on one side of the hydraulic torque converter TC and is arranged at intervals with the hydraulic torque converter TC, the first spur gear 1 and the second spur gear 2 are arranged at the input end of the hydraulic torque converter TC and are connected with an engine of the crawler fire engine, the third spur gear 3 and the fourth spur gear 4 are arranged at the input end of the oil supply pump P1 and are connected with the engine of the crawler fire engine, the first spur gear 1, the second spur gear 2, the third spur gear 3 and the fourth spur gear 4 are connected with the engine of the crawler fire engine through a fifth shaft V, the hydraulic system is matched with the hydraulic torque converter TC through the oil supply pump P1, the first spur gear 1, the second spur gear 2, the third spur gear 3 and the fourth spur gear 4 to form a power output part of the crawler fire engine, wherein the oil supply pump P1 is used for working under the action of the engine, the third spur gear 3 and the fourth spur gear 2 are used as power input gears of the hydraulic torque converters P1 and are used as power input gears of the engine, and the fourth spur gears 2 are used for receiving the power input from the engine P1 and are used as power input gears of the engine.

The hydraulic torque converter further comprises a fifth spur gear 5 and a sixth spur gear 6, wherein the fifth spur gear 5 and the sixth spur gear 6 are arranged at the output end of the hydraulic torque converter TC, and the fifth spur gear 5 and the sixth spur gear 6 are used as output end gears of the hydraulic torque converter TC.

The speed change system comprises a first shaft I, a second shaft II, a first planetary gear PGS1 and a second planetary gear PGS2, wherein the first shaft I is arranged at the output end of the hydraulic torque converter TC and is connected with the output end of the hydraulic torque converter TC through an input assembly, the second shaft II is arranged parallel to the first shaft I, the first planetary gear PGS1 and the second planetary gear PGS2 are symmetrically arranged at two ends of the second shaft II, the speed change system is matched with the first shaft I, the second shaft II, the first planetary gear PGS1 and the second planetary gear PGS2 to adjust the travelling speed of the crawler firefighting vehicle, the first shaft I and the second shaft II jointly form a transmission shaft structure in the comprehensive transmission device, the first planetary gear PGS1 and the second planetary gear PGS2 are busbar planetary gears which are used for being connected with the steering system, when the crawler firefighting vehicle runs normally, and the steering system is in a locking state, and the first planetary gear PGS1 and the second planetary gear PGS2 are directly output.

The input assembly comprises an input shaft IV, a seventh bevel gear 7 and an eighth bevel gear 8, wherein the input shaft IV is arranged between the first shaft I and the sixth straight gear 6, one end of the input shaft IV is fixedly connected with the sixth straight gear 6, the seventh bevel gear 7 is arranged at one end of the input shaft IV, which is far away from the sixth straight gear 6, the eighth bevel gear 8 is arranged in the middle of the first shaft I and is meshed with the seventh bevel gear 7, the input assembly is matched with the seventh bevel gear 7 and the eighth bevel gear 8 through the input shaft IV, the seventh bevel gear 7 and the eighth bevel gear 8 to connect a speed changing system with a hydraulic system, the input shaft IV is connected with a sixth gear at the output end of the hydraulic torque converter TC, and the seventh bevel gear 7 and the eighth bevel gear 8 are used for forming a transmission gear structure between the input shaft IV and the first shaft I to realize connection of the speed changing system and the hydraulic system.

The hydraulic gear shifting device further comprises a first gear clutch C1, a reverse gear clutch C2, a second gear clutch C3, a third gear clutch C4 and a fourth gear clutch C5, wherein the first gear clutch C1, the reverse gear clutch C2, the second gear clutch C3, the third gear clutch C4 and the fourth gear clutch C5 are arranged on the first shaft I at intervals side by side, the first gear clutch C1, the reverse gear clutch C2, the second gear clutch C3, the third gear clutch C4 and the fourth gear clutch C5 form five hydraulic clutch structures on the first shaft I together, and the combination and the separation of the clutches are controlled through a hydraulic system, so that the switching between five gears of four positive gears and one reverse gear can be realized.

The gear further comprises a first gear set, a reverse gear set, a second gear set, a third gear set and a fourth gear set, wherein the first gear set consists of a ninth straight gear 9 and a nineteenth straight gear 19 which are respectively arranged on a first shaft I and a second shaft II, the ninth straight gear 9 is meshed with the nineteenth straight gear 19, the reverse gear set consists of a tenth straight gear 10 and a twentieth straight gear 20 which are respectively arranged on the first shaft I and the second shaft II, the tenth straight gear 10 is meshed with the twentieth straight gear 20 through a seventeenth straight gear 17, the second gear set consists of a fourteenth straight gear 14 and a twenty first straight gear 21 which are respectively arranged on the first shaft I and the second shaft II, the fourteenth straight gear 14 is meshed with the twenty first straight gear 21, the third gear set consists of a fifteenth spur gear 15 and a twenty-second spur gear 22 which are respectively arranged on a first shaft I and a second shaft II, the fifteenth spur gear 15 is meshed with the twenty-second spur gear 22, the fourth gear set consists of a sixteenth spur gear 16 and a twenty-third spur gear 23 which are respectively arranged on the first shaft I and the second shaft II, the sixteenth spur gear 16 is meshed with the twenty-third spur gear 23, the first gear set is controlled by a first gear clutch C1, the reverse gear set is controlled by a reverse gear clutch C2, the second gear set is controlled by a second gear clutch C3, the third gear set is controlled by a third gear clutch C4, and the fourth gear set is controlled by a fourth gear clutch C5, namely, the meshing and the separating of gears in the corresponding gear sets are controlled by the clutches, so that the switching between five gears of four normal gears and one reverse gear is realized.

The eighteenth speed change gear 18 and the twenty-fourth speed change gear 24 are symmetrically arranged at two ends of the second shaft ii, wherein the eighteenth speed change gear 18 and the twenty-fourth speed change gear 24 are used as speed change gear structures at the end parts of the second shaft ii.

The steering system comprises a steering pump PM, a zero shaft III and a steering motor P2, wherein the input end of the steering pump PM is connected with a first shaft I through an eleventh straight gear 11, a twelfth straight gear 12 and a thirteenth straight gear 13, the zero shaft III and a second shaft II are mutually parallel, a thirty-first straight gear 30 is arranged in the middle of the zero shaft III, the input end of the steering motor P2 is meshed with the thirty-first straight gear 30 through a thirty-second straight gear 32 and a thirty-first straight gear 31, a twenty-seventh straight gear 27 and a twenty-ninth straight gear 29 are symmetrically arranged at two ends of the zero shaft III, the twenty-seventh straight gear 27 and the twenty-ninth straight gear 29 are meshed with a corresponding first planetary gear PGS1 and a second planetary gear PGS2 through idler gears, the steering system is matched with the steering pump PM, the zero shaft III and the steering motor P2 to realize left and right steering of the crawler firefighting vehicle, the steering pump PM is used for working under the action of the first shaft I, the zero shaft is used for connecting the steering motor P2 with the first planetary gear PGS1 and the second planetary gear PGS2 to realize left and right steering of the crawler firefighting vehicle through the idler gears PGS1 and the second planetary gear PGS 2.

The idler gears include a twenty-fifth idler gear 25, a twenty-sixth idler gear 26, and a twenty-eighth idler gear 28, the twenty-fifth idler gear and the twenty-sixth idler gear 26 being disposed between the first planet row PGS1 and the twenty-seventh spur gear 27, the twenty-eighth idler gear 28 being disposed between the second planet row PGS2 and the twenty-ninth spur gear 29, wherein the twenty-fifth idler gear 25 and the twenty-sixth idler gear 26 are configured to connect the twenty-seventh spur gear 27 at one end of the zero axis iii with the first planet row PGS1, and the twenty-eighth idler gear 28 is configured to connect the twenty-ninth spur gear 29 at one end of the zero axis iii with the second planet row PGS 2.

Working principle:

when the crawler fire truck works, the engine drives the hydraulic torque converter TC to work, meanwhile, the oil supply pump P1 is driven to cool the hydraulic torque converter TC, the hydraulic torque converter TC drives the first shaft I to rotate through the input component, the combination and the separation of the corresponding gear clutch are controlled through the hydraulic system, so that the engagement and the separation of gears in the corresponding gear set are controlled, the first shaft I and the second shaft II are connected through the corresponding gear set, further, the switching between five gears of four positive gears and one reverse gear is realized, when the truck normally runs, the steering system is in a locking state, the first planetary gear PGS1 and the second planetary gear PGS2 are directly output, due to the differential arrangement of idler wheels, when the crawler fire truck steers, the output rotation speeds of the first planetary gear PGS1 and the second planetary gear PGS2 are different, the steering function of the crawler fire truck is realized through controlling the selection direction of the steering motor P2, and when the crawler fire truck is in a neutral gear, the steering function is realized through the output of the first planetary gear PGS1 and the second planetary gear PGS 2.

The hydraulic transmission and hydrostatic transmission combined device has the advantages that the hydraulic system, the speed change system and the steering system are matched to form the hydraulic transmission and hydrostatic transmission combined device, the hydraulic transmission and hydrostatic transmission combined device has good maneuvering performance, the response time of the fire truck for treating various emergencies can be effectively shortened, property loss is reduced, the control is easy, the center steering can be realized, the fire truck can cope with various emergencies in complex and changeable forest road conditions, the electrohydraulic manual gear shifting is adopted, the control is easy, and the load of a driver is reduced.

The foregoing describes one embodiment of the present utility model in detail, but the disclosure is only a preferred embodiment of the present utility model and should not be construed as limiting the scope of the utility model. All equivalent changes and modifications within the scope of the present utility model are intended to be covered by the present utility model.

Claims

1. The hydraulic mechanical comprehensive transmission device of the crawler fire truck comprises a hydraulic Torque Converter (TC), wherein the hydraulic Torque Converter (TC) is arranged at one end of the comprehensive transmission device, and the hydraulic mechanical comprehensive transmission device is characterized by further comprising a hydraulic system for outputting power, a speed changing system for adjusting the traveling speed of the crawler fire truck and a steering system for controlling the traveling direction of the crawler fire truck, wherein the hydraulic system is positioned at the output end of the hydraulic Torque Converter (TC), the speed changing system is arranged at one side of the hydraulic system far away from the hydraulic Torque Converter (TC), and the steering system is arranged at one side of the speed changing system far away from the hydraulic system.

2. The hydraulic mechanical integrated transmission device of the crawler fire truck according to claim 1, wherein the hydraulic system comprises an oil supply pump (P1), a first spur gear (1), a second spur gear (2), a third spur gear (3) and a fourth spur gear (4), the oil supply pump (P1) is configured at one side of the hydraulic Torque Converter (TC) and is arranged at intervals with the hydraulic Torque Converter (TC), the first spur gear (1) and the second spur gear (2) are arranged at the input end of the hydraulic Torque Converter (TC) and are connected with an engine of the crawler fire truck, the third spur gear (3) and the fourth spur gear (4) are arranged at the input end of the oil supply pump (P1) and are connected with the engine of the crawler fire truck, and the first spur gear (1), the second spur gear (2), the third spur gear (3) and the fourth spur gear (4) are connected with the engine of the crawler fire truck through a fifth shaft (v).

3. A crawler fire truck hydromechanical integrated transmission according to claim 2, further comprising a fifth spur gear (5) and a sixth spur gear (6), the fifth spur gear (5) and the sixth spur gear (6) being arranged at the output of the Torque Converter (TC).

4. A crawler fire truck hydromechanical integrated transmission as claimed in claim 3, wherein the transmission system comprises a first shaft (i), a second shaft (ii), a first planetary row (PGS 1) and a second planetary row (PGS 2), the first shaft (i) being arranged at the output of the Torque Converter (TC) and connected to the output of the Torque Converter (TC) via an input assembly, the second shaft (ii) being arranged parallel to the first shaft (i), the first planetary row (PGS 1) and the second planetary row (PGS 2) being arranged symmetrically at both ends of the second shaft (ii).

5. The hydraulic mechanical integrated transmission device of a crawler fire truck according to claim 4, wherein the input assembly comprises an input shaft (iv), a seventh bevel gear (7) and an eighth bevel gear (8), the input shaft (iv) is disposed between the first shaft (i) and the sixth spur gear (6) and one end of the input shaft is fixedly connected with the sixth spur gear (6), the seventh bevel gear (7) is disposed at one end of the input shaft (iv) far away from the sixth spur gear (6), and the eighth bevel gear (8) is disposed in the middle of the first shaft (i) and is meshed with the seventh bevel gear (7).

6. The hydraulic mechanical integrated transmission device of the crawler fire truck according to claim 4, further comprising a first gear clutch (C1), a reverse gear clutch (C2), a second gear clutch (C3), a third gear clutch (C4) and a fourth gear clutch (C5), wherein the first gear clutch (C1), the reverse gear clutch (C2), the second gear clutch (C3), the third gear clutch (C4) and the fourth gear clutch (C5) are arranged on the first shaft (i) at intervals side by side.

7. A hydraulic mechanical integrated transmission for a crawler fire truck according to claim 6, further comprising a first gear set, a reverse gear set, a second gear set, a third gear set and a fourth gear set, wherein the first gear set is composed of a ninth spur gear (9) and a nineteenth spur gear (19) which are respectively arranged on the first shaft (I) and the second shaft (II), the ninth spur gear (9) is meshed with the nineteenth spur gear (19), the reverse gear set is composed of a tenth spur gear (10) and a twenty-first spur gear (20) which are respectively arranged on the first shaft (I) and the second shaft (II), the tenth spur gear (10) is meshed with the twenty-first spur gear (17) through the seventeenth spur gear, the second gear set is composed of a fourteenth spur gear (14) and a twenty-first spur gear (21) which are respectively arranged on the first shaft (I) and the second shaft (II), the fourteenth spur gear (14) is meshed with the twenty-first spur gear (15) and the twenty-first spur gear (22) is meshed with the twenty-first spur gear (15) and the twenty-first spur gear (21) is respectively arranged on the twenty-second shaft (II), the fourth gear set is composed of a sixteenth straight gear (16) and a twenty-third straight gear (23) which are respectively arranged on the first shaft (I) and the second shaft (II), and the sixteenth straight gear (16) is meshed with the twenty-third straight gear (23).

8. The hydraulic and mechanical integrated transmission device of a crawler fire truck according to claim 7, further comprising an eighteenth speed change gear (18) and a twenty-fourth speed change gear (24), wherein the eighteenth speed change gear (18) and the twenty-fourth speed change gear (24) are symmetrically arranged at both ends of the second shaft (ii).

9. The hydraulic mechanical integrated transmission device of a crawler fire truck according to claim 8, wherein the steering system comprises a steering Pump (PM), a zero shaft (iii) and a steering motor (P2), an input end of the steering Pump (PM) is connected with the first shaft (i) through an eleventh spur gear (11), a twelfth spur gear (12) and a thirteenth spur gear (13), the zero shaft (iii) and the second shaft (ii) are arranged in parallel with each other, a thirty-first spur gear (30) is arranged in the middle of the zero shaft (iii), an input end of the steering motor (P2) is meshed with the thirty-first spur gear (30) through a thirty-second spur gear (32) and a thirty-first spur gear (31), twenty-seventh spur gears (27) and twenty-ninth spur gears (29) are symmetrically arranged at two ends of the zero shaft (iii), and the twenty-seventh spur gears (27) and the twenty-ninth gears (29) are meshed with the corresponding twenty-first row (s 1) and the second planet row (s 2) through idler gears.

10. A track fire truck hydromechanical integrated transmission as claimed in claim 9, wherein the idler wheels comprise a twenty-fifth idler wheel (25), a twenty-sixth idler wheel (26) and a twenty-eighth idler wheel (28), the twenty-fifth idler wheel and the twenty-sixth idler wheel (26) being disposed between the first planet row (PGS 1) and the twenty-seventh spur gear (27), the twenty-eighth idler wheel (28) being disposed between the second planet row (PGS 2) and the twenty-ninth spur gear (29).