Dual-mode transmission with on-site steering and one-side brake steering

Abstract

The present invention provides a dual-mode gearbox with in-situ steering and unilateral braking steering. The gearbox includes a housing, a drive assembly, a speed transmission assembly, a reversing and braking assembly, the drive assembly includes a reversing shaft assembly, a left drive shaft assembly and a right drive shaft assembly, the speed transmission assembly includes a power input shaft assembly, a reverse shaft assembly and a secondary speed change shaft assembly, the reversing and braking assembly includes a brake shaft, a reversing driving gear, a reversing clutch gear, a reversing clutch assembly, a shift fork and a brake assembly; the reversing shaft assembly includes a reversing shaft, a reversing gear, a left drive gear assembly, an intermediate transmission gear and a right drive gear assembly; the left drive gear assembly is provided with a left steering fork; the right drive gear assembly is provided with a right steering fork. Compared with the related art, the gearbox provided by the present invention can realize both in-situ steering and traditional unilateral braking steering, ensuring safe driving on complex terrain.

Description

Technical Field

[0001] The invention relates to the technical field of agricultural machinery, and in particular to a dual-mode gearbox with in-situ steering and single-side braking steering. Background Art

[0002] Existing crawler vehicles all use rubber crawler-type running mechanisms, and their core components are running gearboxes. Steering performance is one of the main indicators for judging the quality of running gearboxes. Currently, the steering mechanisms of crawler vehicle gearboxes are formed in the following ways:

[0003] 1. Hydraulic transmission

[0004] It uses two pumps and two hydraulic motors for transmission. The two tracks are connected to a hydraulic motor respectively, and the hydraulic pump provides power, thus forming a double-flow transmission. The rotation direction of the motor is controlled by a hydraulic valve to achieve forward movement and in-situ steering of the vehicle. This method is costly and the maintenance and repair of hydraulic components are difficult;

[0005] (ii) Using brake steering mechanism

[0006] The steering mechanism generally includes a tooth clutch, a friction brake and an operating device, wherein the friction brake is fixedly connected to the housing of the gearbox to achieve steering by cutting off the power of the tooth clutch on one side and braking the friction brake. When the tracked vehicle is moving straight, the tooth clutch is engaged and the friction brake is disengaged; when turning, the shift fork is operated to cut off the power of the tooth clutch on the steering side, and the brake friction device on that side is engaged, so that the track on that side is braked and stopped, so that one of the two tracks of the tracked agricultural vehicle moves and the other stops, thereby achieving braking steering. The tracked vehicle adopting this method has a low turning speed because it adopts braking steering, so it has a relatively high safety performance when walking and transferring on the rugged roads in the southern hilly and mountainous areas; the full gear mechanical transmission it adopts has a higher transmission efficiency than the hydraulic transmission, low energy loss, and relatively low production and maintenance costs; but when turning, there is a large turning radius, low work efficiency when working in small plots of field, and when turning in paddy fields, because only one side of the track rotates, it is easy to get stuck, and the paddy field passability is poor.

[0007] Existing patents such as announcement number CN205064715U disclose a mechanical in-situ steering gearbox, which can achieve the effect of in-situ steering of a crawler tractor by shifting the differential shift gear to engage the internal meshing tooth clutch of the intermediate transmission gear or the reverse gear; since the reverse gear in this solution is constantly rotating and the reverse gear is a tooth-type rigid clutch, this steering method can only achieve sharp turns and cannot accurately control the turning radius. Turning at high speed and high gear is prone to cause accidents such as rollover.

[0008] For another example, patent announcement number CN207750466U discloses an improved forward and reverse steering structure for a clutch gear of an agricultural machinery transmission. By controlling the two left and right linked gears and the friction clutch, the effect of in-situ steering of the tracked agricultural machinery can be achieved. Since this solution does not have a unilateral brake steering mechanism, it can only rely on forward and reverse turning. Since the two tracks rotate simultaneously, one forward and one reverse, the turning speed is doubled. Turning at high speed and high gear can easily cause accidents such as rollover.

[0009] For another example, patent publication number CN106931090A discloses a crawler gearbox crawler reversing device, which can achieve the effect of crawler agricultural machinery turning in situ by controlling the left and right steering gears and the friction clutch. Since this solution does not have a unilateral brake steering mechanism, it can only rely on forward and reverse turning. Since the two crawlers rotate simultaneously, one forward and one reverse, the turning speed is doubled. Turning at high speed and high gear is prone to cause accidents such as rollover.

[0010] For another example, patent publication number CN112240372A discloses a fixed-axis wheel type mechanical on-the-spot steering gearbox. By setting a control shaft and using a diaphragm clutch to directly control two half-axle gears, the effect of on-the-spot steering of the track can be achieved. This scheme has two disadvantages. First, since this scheme does not have a single-sided brake steering mechanism, turning can only rely on forward and reverse turning. Since the two tracks rotate simultaneously, one forward and one reverse, the turning speed is doubled. Turning at high speed and high gear is prone to cause rollover and other accidents; second, since the diaphragm clutch is used to directly control the two half-axle gears without deceleration through the reduction gear in the middle, the friction force on the solid diaphragm is very large, the friction plate is easy to wear, and it is not durable. Summary of the invention

[0011] The purpose of the present invention is to provide a dual-mode gearbox with in-situ steering and unilateral braking steering, which has both an in-situ steering and walking mode and a braking steering mode of a transmission gearbox, thereby improving mechanical maneuverability and reducing energy consumption.

[0012] The technical scheme of the present invention is: a dual-mode gearbox with in-situ steering and single-side braking steering comprises a housing and a driving assembly and a speed transmission assembly installed in the housing, the driving assembly comprises a left driving shaft assembly for realizing left steering and a right driving shaft assembly for realizing right steering, the speed transmission assembly comprises a power input shaft assembly, a reverse gear shaft assembly and an auxiliary speed transmission shaft assembly, the dual-mode gearbox with in-situ steering and single-side braking steering also comprises a reverse and brake assembly, the reverse and brake assembly comprises a brake shaft, and a reverse driving gear, a reverse clutch gear, a reverse clutch assembly, a shift fork and a brake brake assembly sequentially installed on the brake shaft; the reverse clutch gear is constantly meshed with a corresponding gear in the reverse gear shaft assembly, the reverse clutch gear is installed on the brake shaft through a bearing, and the reverse clutch assembly is fixed on the reverse clutch gear;

[0013] The driving assembly also includes a countershaft assembly, which includes a countershaft and a counter gear, a left driving gear assembly, an intermediate transmission gear and a right driving gear assembly sequentially mounted on the countershaft; the left driving gear assembly is provided with a left steering fork capable of controlling the sliding of the countershaft along the countershaft; the right driving gear assembly is provided with a right steering fork capable of controlling the sliding of the countershaft along the countershaft; the counter gear is meshed with the counter driving gear; the left driving gear assembly is meshed with the corresponding gear on the left driving shaft assembly, and the right driving gear assembly is meshed with the right driving shaft assembly; the intermediate transmission gear is constantly meshed with the corresponding gear on the auxiliary transmission shaft assembly.

[0014] Preferably, the left driving gear assembly comprises a left return spring and a left driving gear, one end of the left return spring is sleeved in the left driving gear, and the other end is in contact with a first bearing provided in the reversing gear; one end of the left driving gear away from the left return spring is connected to the intermediate transmission gear;

[0015] The right driving gear assembly comprises the right driving gear, a right return spring and a right rotating wheel; one end of the right driving gear is connected to the intermediate transmission gear, and the other end is provided with the right return spring; the right rotating wheel is arranged at intervals beside the right driving gear, and a second bearing is arranged in the right rotating wheel, and the second bearing abuts against the right return spring;

[0016] The left drive gear and the right drive gear can rotate and slide freely along the counter shaft respectively; the left drive gear is meshed with the corresponding gear on the left drive shaft assembly, and the right drive gear is meshed with the right drive shaft assembly.

[0017] Preferably, a toothed insert that is pressed into engagement with the end side of the counter gear is provided on the end side of the left driving gear; and a toothed insert that is pressed into engagement with the end side of the right rotating wheel is provided on the end side of the right driving gear.

[0018] Preferably, internal teeth are provided on both sides of the intermediate transmission gear; external teeth meshing with the internal teeth on one side of the intermediate transmission gear are provided on the outer circumferential surface of the left driving gear; and external teeth meshing with the internal teeth on the other side of the intermediate transmission gear are provided on the outer circumferential surface of the right driving gear.

[0019] Preferably, the reversing gear and the right-turning wheel are respectively mounted on the reversing shaft via splines or flat keys; and the intermediate transmission gear is mounted in the middle of the reversing shaft via a bearing or a steel sleeve.

[0020] Preferably, the power input shaft assembly comprises an input shaft and a third gear driving gear, a reverse gear driving gear, a second gear driving gear and a first gear driving gear sequentially mounted on the input shaft; the first gear driving gear slides along the input shaft;

[0021] The speed transmission assembly further includes a shift shaft assembly, which includes a shift shaft and a third-gear and reverse-gear shift gear, a second-gear driven gear, a secondary-speed driving gear, and a first-gear driven gear sequentially mounted on the shift shaft; the third-gear and reverse-gear shift gear slides along the shift shaft, and when sliding, the third-gear and reverse-gear shift gear meshes with the third-gear driving gear, or the third-gear and reverse-gear shift gear meshes with the reverse-gear driving gear; the second-gear driving gear meshes with or does not mesh with the second-gear driven gear when sliding;

[0022] The reverse gear shaft assembly comprises a reverse gear shaft and a reverse gear intermediate gear mounted on the reverse gear shaft;

[0023] The auxiliary speed-change shaft assembly comprises an auxiliary speed-change shaft, an auxiliary speed-change shift gear and an auxiliary speed-change low-speed gear driven gear which are sequentially mounted on the auxiliary speed-change shaft; the auxiliary speed-change shift gear slides along the auxiliary speed-change shaft to mesh with the auxiliary speed-change low-speed gear driven gear or with the second-speed gear driven gear; the intermediate transmission gear is constantly meshed with the auxiliary speed-change shift gear;

[0024] The second gear driven gear is constantly meshed with the second gear driving gear; the auxiliary speed driving gear is constantly meshed with the auxiliary speed low speed gear driven gear; the reverse gear intermediate gear is constantly meshed with the third gear and reverse gear shift gears; the reverse gear intermediate gear is constantly meshed with the reverse gear driving gear; the reverse gear intermediate gear is constantly meshed with the reverse clutch gear.

[0025] Preferably, the auxiliary transmission low-speed gear driven gear is mounted on the auxiliary transmission shaft via a bearing, and the auxiliary transmission low-speed gear driven gear is provided with internal teeth, which mesh with part of the external teeth of the auxiliary transmission shift gear.

[0026] Preferably, the reverse gear is meshed with the reverse driving gear via a reverse transfer gear, and the reverse transfer gear is mounted on the box body via a reverse transfer shaft.

[0027] Preferably, the reverse clutch assembly includes a reverse clutch cover, a reverse clutch friction plate, a reverse clutch steel plate, a reverse clutch spline hub and a reverse clutch pressure plate, the reverse clutch cover and the reverse clutch pressure plate cover each other to form a cavity, within the cavity, the reverse clutch steel plate is mounted on the brake shaft through the reverse clutch spline hub; the brake assembly has the same structure as the reverse clutch assembly, and the two are symmetrically arranged; the brake assembly is mounted on the housing on a side away from the reverse clutch assembly.

[0028] Preferably, the left drive shaft assembly includes a left output shaft and a left gear mounted on the left output shaft; the right drive shaft assembly includes a right output shaft and a right gear mounted on the right output shaft; the left gear meshes with the left drive gear, and the right gear meshes with the right drive gear.

[0029] Compared with the related art, the present invention has the following beneficial effects:

[0030] 1. The in-situ steering is achieved by controlling the reverse clutch assembly, and the switching of the two modes of unilateral braking steering is achieved by controlling the brake assembly. Both the in-situ steering and the unilateral braking steering of the traditional gearbox can be achieved, ensuring the safe driving of the vehicle in complex terrain conditions such as hilly and mountainous areas, and preventing rollover due to high-speed turning.

[0031] Second, the brake steering and forward and reverse steering are both operated by the joystick driving the shift fork, which is consistent with the steering operation of the traditional mechanical gearbox, simple and convenient, and does not increase the operating steps;

[0032] 3. The reverse clutch assembly and the brake assembly transmit power to the output shaft drive gear after multi-stage deceleration, reducing the torque of the clutch and brake assemblies and making the friction plates on the reverse clutch assembly and the brake assembly more wear-resistant and durable. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 A schematic structural diagram of a dual-mode transmission with in-situ steering and single-side braking steering provided by the present invention;

[0034] Figure 2 for Figure 1 Schematic diagram of the internal three-dimensional structure;

[0035] Figure 3 for Figure 2 The left schematic diagram of

[0036] Figure 4 For along Figure 1 AA cross-sectional view of ;

[0037] Figure 5 For along Figure 1 BB cross-sectional view;

[0038] Figure 6 for Figure 5 A schematic diagram of the structure of the reversing and braking components;

[0039] Figure 7 for Figure 5 Schematic diagram of the structure of the reverse shaft component in the drive component.

[0040] In the attached drawings: 1, input shaft; 11, third gear driving gear; 12, reverse gear driving gear; 13, second gear driving gear; 14, first gear driving gear; 2, shift shaft; 21, third gear and reverse gear shift gear; 22, second gear driven gear; 23, auxiliary speed driving gear; 24, first gear driven gear; 3, reverse shaft; 31, reverse intermediate gear; 4, auxiliary speed shaft; 41, auxiliary speed shift gear; 42, auxiliary speed low gear driven gear; 5, brake shaft; 51, reverse driving gear; 52, reverse clutch gear; 53, reverse clutch assembly; 54, shift fork; 55, brake assembly; 56, reverse clutch cover; 57, reverse clutch friction plate; 58, reverse clutch steel plate; 59, reverse clutch spline hub; 510, reverse Clutch pressure plate; 511, reverse clutch thrust bearing; 512, brake pressure plate; 513, brake friction plate; 514, brake steel plate; 515, brake hub; 516, brake thrust bearing; 517, brake spline hub; 6, reverse transfer shaft; 61, reverse transfer gear; 7, reverse shaft; 71, reverse gear; 72, first bearing; 73, left return spring; 74, left drive gear; 75, left steering fork; 76, intermediate transmission gear; 77, intermediate bearing; 78, right steering fork; 79, right drive gear; 710, right return spring; 711, second bearing; 712, right steering wheel; 8, left output shaft; 81, left gear; 9, right output shaft; 91, right gear; 10, housing. DETAILED DESCRIPTION

[0041] The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments. It should be noted that the embodiments of the present invention and the features in the embodiments can be combined with each other without conflict. For the convenience of description, if the words "upper", "lower", "left" and "right" appear in the following, they only indicate that the upper, lower, left and right directions are consistent with the drawings themselves, and do not limit the structure.

[0042] like Figure 1~Figure 3 As shown, the dual-mode transmission with in-situ steering and single-side braking steering provided in this embodiment includes a housing 10 and a drive assembly, a speed transmission assembly, a reverse and brake assembly installed in the housing 10.

[0043] The speed transmission assembly includes a power input shaft assembly, a reverse gear shaft assembly, a secondary speed change shaft assembly and a shift shaft assembly. Power is input to the drive assembly in two ways from the power input shaft, the first way is input from the speed transmission assembly, and the second way is input from the reverse and brake assembly.

[0044] The driving assembly includes a countershaft assembly, a left driving shaft assembly for realizing left steering, and a right driving shaft assembly for realizing right steering.

[0045] like Figure 5 As shown, the reverse and brake assembly includes a brake shaft 5, and a reverse driving gear 51, a reverse clutch gear 52, a reverse clutch assembly 53, a shift fork 54 and a brake assembly 55 which are sequentially installed on the brake shaft 5.

[0046] like Figure 5 , Figure 6 As shown, the reverse clutch assembly 53 includes a reverse clutch cover 56, a reverse clutch friction plate 57, a reverse clutch steel plate 58, a reverse clutch spline hub 59 and a reverse clutch pressure plate 510, and the reverse clutch cover 56 and the reverse clutch pressure plate 510 are covered to form a cavity. In the cavity, the reverse clutch steel plate 58 is installed on the brake shaft 5 through the reverse clutch spline hub 59. The reverse clutch friction plate 57 is a wet friction plate, which is embedded in the reverse clutch cover 56 and rotates together with the reverse clutch cover 56. The reverse clutch pressure plate 510 can slide along the axial direction of the brake shaft 5. The reverse driving gear 51 is fixedly connected to the reverse clutch cover 56 by bolts.

[0047] The brake assembly 55 has the same structure as the reverse clutch assembly 53, and the two are symmetrically arranged. Specifically, the brake assembly 55 includes a brake pressure disc 512, a brake friction pad 513, a brake steel pad 514, a brake hub 515 and a brake spline hub 517. The brake hub 515 and the brake pressure disc 512 are covered to form a cavity. In the cavity, the brake friction pad 513 is installed on the brake hub 515; the brake steel pad 514 is installed on the brake shaft 5 through the brake spline hub 517. The brake hub 515 is installed on the box 10. The brake friction pad 513 is a wet friction pad. The brake pressure disc 512 can slide along the axial direction of the brake shaft 5.

[0048] A reverse clutch thrust bearing 511 is mounted on one end of the reverse clutch pressure plate 510 away from the reverse clutch cover 56. A brake thrust bearing 516 is mounted on one end of the brake pressure cover 512 away from the brake hub 515. The shift fork 54 is arranged between the reverse clutch thrust bearing 511 and the brake thrust bearing 516. A bearing is arranged at the mounting position of the brake shaft 5 and the housing 10.

[0049] like Figure 5 , Figure 7 As shown, the driving assembly further comprises a countershaft 7 and a counter gear 71, a left driving gear assembly, an intermediate transmission gear 76 and a right driving gear assembly which are sequentially mounted on the countershaft 7. The counter gear 71 is a toothed gear.

[0050] The left driving gear assembly is provided with a left steering fork 75 capable of controlling the sliding of the reverse shaft 7. The right driving gear assembly is provided with a right steering fork 78 capable of controlling the sliding of the reverse shaft 7. The reverse gear 71 is meshed with the reverse driving gear 51.

[0051] The reverse gear 71 is fixedly mounted on the reverse shaft 7, and a first bearing 72 is provided inside the reverse gear 71 and is sleeved on the reverse shaft 7. The right steering wheel 712 is fixedly mounted on the reverse shaft 7, and a second bearing 711 is provided inside the right steering wheel 712 and is sleeved on the reverse shaft 7. The intermediate transmission gear 76 is mounted on the reverse shaft 7 through an intermediate bearing 77.

[0052] The left driving gear assembly includes a left return spring 73 and a left driving gear 74. One end of the left return spring 73 is sleeved in the left driving gear 74, and the other end is in contact with the first bearing 72 in the counter gear 71. The left steering fork 75 is used to drive the left driving gear 74 to slide along the counter shaft 7.

[0053] One end of the left driving gear 74 away from the left return spring 73 is connected to the intermediate transmission gear 76. The connection mode can be: both sides of the intermediate transmission gear 76 are provided with internal teeth, and the outer circumferential surface of the left driving gear 74 is provided with external teeth meshing with the internal teeth on one side of the intermediate transmission gear 76.

[0054] The right driving gear assembly includes the right driving gear 79, a right return spring 710 and a right turning wheel 712. The right turning wheel 712 is a toothed wheel. One end of the right driving gear 79 is connected to the intermediate transmission gear 76, and the other end is provided with the right return spring 710. The right turning wheel 712 is arranged at intervals beside the right driving gear 79, and the right return spring 710 abuts against the second bearing 711 in the right driving gear 79. Similarly, the outer circumferential surface of the right driving gear 79 is provided with external teeth that mesh with the internal teeth on the other side of the intermediate transmission gear 76. The right steering fork 78 is used to drive the right steering wheel 712 to slide along the reversing shaft 7. The first bearing 72 and the second bearing 711 are both thrust bearings.

[0055] The end side of the left driving gear 74 is provided with a toothed insert that is pressed into engagement with the end side of the counter gear 71. The end side of the right driving gear 79 is provided with a toothed insert that is pressed into engagement with the end side of the right rotating wheel 712.

[0056] The left driving gear 74 and the right driving gear 79 can rotate and slide freely along the reversing shaft 7. The left return spring 73, the intermediate transmission gear 76 and the right return spring 710 can rotate freely along the reversing shaft 7. Free rotation means slipping without transmitting power.

[0057] The counter gear 71 and the right wheel 712 are respectively mounted on the counter shaft 7 through splines or flat keys. In other embodiments, the intermediate transmission gear 76 can also be mounted in the middle of the counter shaft 7 through a steel sleeve.

[0058] The counter-rotating intermediate gear 61 is always meshed with the counter-rotating gear 71. The rotation direction of the counter-rotating shaft 7 is opposite to the rotation direction of the intermediate transmission gear 76.

[0059] The switching between the reverse steering mode and the brake steering mode is realized by controlling the shift fork 54 to press the reverse clutch pressure plate 510 or the brake pressure plate 512. The reverse clutch assembly 53 and the brake assembly 55 are in a normally disengaged state. When the shift fork 54 presses the reverse clutch pressure plate 510, the reverse clutch assembly 53 is closed, and the reverse clutch spline hub 59 and the reverse clutch cover 56 rotate together, driving the reverse driving gear 51 on the brake shaft 5 to rotate. The reverse driving gear 51 is normally meshed with the reverse transfer gear 61.

[0060] Under the action of external force, the shift fork 54 leaves the reverse clutch pressure plate 510, the reverse clutch assembly 53 is in a disengaged state, the brake shaft 5 is in a stationary state, and similarly, the reverse shaft 7 is also in a stationary state. The brake steering or braking of the crawler track is achieved by combining the teeth on the reverse gear 71 and the right steering wheel 712.

[0061] like Figure 5As shown, the left drive shaft assembly includes a left output shaft 8 and a left gear 81 mounted on the left output shaft 8. The right drive shaft assembly includes a right output shaft 9 and a right gear 91 mounted on the right output shaft 9. The left gear 81 is constantly meshed with the left drive gear 74, and the right gear 91 is constantly meshed with the right drive gear 79.

[0062] like Figure 5 , Figure 7 As shown, the parts where the reversing shaft 7 and the housing 10 are installed are connected via end covers and bearings.

[0063] like Figure 2~Figure 4 As shown, the power input shaft assembly includes an input shaft 1 and a third gear driving gear 11, a reverse gear driving gear 12, a second gear driving gear 13 and a first gear driving gear 14 which are sequentially mounted on the input shaft 1; the first gear driving gear 14 slides along the input shaft 1. The input shaft 1 is both a power input shaft and a shift shaft of the second and third gear transmission. The third gear driving gear 11 and the reverse gear driving gear 12 are an integral part, and the second gear driving gear 13 and the first gear driving gear 14 are an integral part.

[0064] The shift shaft assembly includes a shift shaft 2 and a third-gear and reverse shift gear 21, a second-gear driven gear 22, a secondary speed driving gear 23 and a first-gear driven gear 24 which are sequentially mounted on the shift shaft 2. The third-gear and reverse shift gear 21 slides along the shift shaft 2, and when sliding, the third-gear and reverse shift gear 21 meshes with the third-gear driving gear 11, or the third-gear and reverse shift gear 21 meshes with the reverse driving gear 12; when the second-gear driving gear 13 slides, it meshes with or does not mesh with the second-gear driven gear 22.

[0065] The reverse gear shaft assembly includes a reverse gear shaft 3 and a reverse gear intermediate gear 31 mounted on the reverse gear shaft 3 .

[0066] The auxiliary speed-change shaft assembly includes an auxiliary speed-change shaft 4, and an auxiliary speed-change shift gear 41 and an auxiliary speed-change low-speed gear driven gear 42 which are sequentially mounted on the auxiliary speed-change shaft 4. The auxiliary speed-change shift gear 41 slides along the auxiliary speed-change shaft 4 to mesh with the auxiliary speed-change low-speed gear driven gear 42, or meshes with the second-speed gear driven gear 22. The intermediate transmission gear 76 is constantly meshed with the auxiliary speed-change shift gear 41.

[0067] The second gear driven gear 22 is constantly meshed with the second gear driving gear 13. The auxiliary speed driving gear 23 is constantly meshed with the auxiliary speed low gear driven gear 42. The reverse gear intermediate gear 31 is constantly meshed with the third gear and reverse gear shift gear 21. The reverse gear intermediate gear 31 is constantly meshed with the reverse gear driving gear 12. The reverse gear intermediate gear 31 is constantly meshed with the reverse clutch gear 52.

[0068] The auxiliary low-speed gear driven gear 42 is installed on the auxiliary speed-change shaft 4 through a bearing. The auxiliary low-speed gear driven gear 42 is provided with internal teeth, and the internal teeth are constantly meshed with part of the external teeth of the auxiliary speed-change shift gear 41 .

[0069] The reverse gear 71 is meshed with the reverse driving gear 51 via a reverse transfer gear 61 , and the reverse transfer gear 61 is mounted on the box body 10 via a reverse transfer shaft 6 .

[0070] The speed changing method of the gearbox provided by the present invention is as follows:

[0071] First gear: Slide the third gear and reverse gear shift gear 21 to the neutral position, then slide the second gear driving gear 13 and the first gear driving gear 14, so that the first gear driving gear 14 is meshed with the first gear driven gear 24 to achieve first gear shift.

[0072] Second gear: Slide the third gear and reverse gear shift gear 21 to the neutral position, then slide the second gear driving gear 13 and the first gear driving gear 14, so that the second gear driving gear 13 and the second gear driven gear 22 are meshed to achieve second gear shifting.

[0073] Third gear: Slide the second gear driving gear 13 and the first gear driving gear 14 to the neutral position, and then slide the third gear and reverse gear shift gear 21 to make the third gear and reverse gear shift gear 21 mesh with the third gear driving gear 11 to achieve third gear shifting.

[0074] Reverse gear: Slide the second gear driving gear 13 and the first gear driving gear 14 to the neutral position, and then slide the third gear and reverse gear shift gear 21 to make the third gear and reverse gear shift gear 21 mesh with the reverse gear intermediate gear 31 to achieve reverse gear shifting.

[0075] Auxiliary transmission high speed gear: The auxiliary transmission shift gear 41 is moved to make it mesh with the second gear driven gear 22 to achieve high speed gear shifting.

[0076] Auxiliary transmission low speed gear: The auxiliary transmission shift gear 41 is moved to make it mesh with the internal teeth of the auxiliary transmission low speed gear driven gear 42 to achieve low speed gear shifting.

[0077] The auxiliary speed change gear 41 on the auxiliary speed change shaft 4 and the intermediate transmission gear on the counter shaft 7 are constantly meshed, so that the power after the speed change is transmitted to the left drive assembly and / or the right drive assembly.

[0078] The power transmission route of the gearbox is divided into two paths. The first path is the transmission of the speed change transmission component to the drive component (such as Figure 4 The second path reverse gear intermediate gear 31 is transmitted to the reverse and brake assembly and then to the left drive assembly and / or the right drive assembly (as shown); Figure 5 as shown).

[0079] When the vehicle is traveling in a straight line: there is no external force to operate the left driving gear 74 and the right driving gear 79, and the power output from the auxiliary speed change gear of the speed change transmission assembly of the gearbox is transmitted to the inner teeth on the left and right sides of the intermediate transmission gear 76. At this time, the intermediate transmission gear 76 is meshed with the left driving gear 74 and the right driving gear 79 respectively. The left power is transmitted from the left driving gear 74 to the left gear 81, then to the left output shaft 8, and finally to the left crawler. The right power is transmitted from the right driving gear 79 to the right gear 91, then to the right output shaft 9, and finally to the right crawler. Since the left output shaft 8 and the right output shaft 9 are in the same direction and at the same speed, the crawler vehicle travels in a straight line.

[0080] Braking mode steering and forward and reverse mode steering:

[0081] Switching of steering modes: when the shift fork 54 is pressed against the brake pressure plate 512 by external force, it is the brake steering mode; when the shift fork 54 is pressed against the reverse clutch pressure plate 510 by external force, it is the forward and reverse steering mode.

[0082] Left turn and left forward and reverse turn: Start the left steering fork 75, and perform the following steps in sequence: Step 1, first move the left drive gear 74 to the left, the left drive gear 74 and the left inner engaging teeth of the intermediate transmission gear 76 are separated, the power of the left drive gear 74 and the intermediate transmission gear 76 is interrupted, and the left drive wheel 74 rotates slowly under the action of the machine inertia. Step 2, the left drive gear 74 continues to move to the left, the left tooth of the left drive gear 74 is embedded in the groove on the right side of the reverse driven gear 71, the left drive gear 74 and the reverse gear 71 are combined, and the reverse or braking force is transmitted to the reverse driving gear 51 through the brake shaft 5 and then to the reverse transfer gear 61, and then to the reverse gear, and then to the left drive gear 74 and then to the left gear 81, and finally to the left track through the left output shaft 8.

[0083] Braking left turn: At this time, when the fork 54 is pressed against the brake pressure plate 512 by external force, the brake assembly 55 is in a braking state, the brake shaft 5 is in a stationary state, and the reverse gear 71 and the left drive gear 73 both stop rotating, thereby realizing the stop of the left track brake and realizing a left turn.

[0084] Forward and reverse left steering: when external force causes the shift fork 54 to press the reverse clutch pressure plate 510, the reverse clutch assembly 53 is in working condition, and the brake shaft 5 rotates driven by the reverse clutch. Since the force transmitted to the reverse gear 71 is one level higher than the force of the intermediate transmission gear 76, the reverse gear 71 and the intermediate transmission gear 76 rotate in opposite directions. The reverse gear 71 rotates in the opposite direction relative to the intermediate transmission gear 76, the left drive gear 74 also rotates in the opposite direction, and the right drive gear 79 rotates forward, thereby realizing the reversal of the left track and the forward rotation of the right track, realizing in-situ steering or small radius steering.

[0085] Right turn and right forward and reverse turn: start the right steering fork 78, and perform the following steps in sequence: Step 1, the right drive gear 79 moves to the right, the right drive gear 79 and the right inner engaging teeth of the intermediate transmission gear 76 are separated, the power of the right drive gear 79 and the intermediate transmission gear 76 is interrupted, and the right drive gear 79 rotates slowly under the action of the machine inertia; Step 2, the right drive gear 79 continues to move to the right, the right side tooth of the right drive gear 79 is embedded in the groove of the right steering wheel 712, the right drive gear 79 and the right reverse tooth wheel 712 are combined, and the braking force is transmitted to the reverse driving gear 51 through the brake shaft 5 and then to the reverse transfer gear 61, and then to the reverse gear 71, and the reverse gear 71 is transmitted to the right steering wheel 72 through the reverse shaft 7, and then the power is transmitted to the right drive gear 79 through the right steering wheel 72, and then to the right gear 91, and finally to the right crawler through the right output shaft 9.

[0086] Braking right turn: At this time, when the fork 54 is pressed against the brake pressure plate 512 by external force, the brake assembly 55 is in a braking state, the brake shaft 5 is in a stationary state, the transmission shaft 7 connected to the brake shaft 5 through multiple gears stops rotating, and the right steering wheel 712 and the right driving gear 79 also stop rotating, thereby realizing the right track brake stopping rotation and realizing a right turn.

[0087] Forward and reverse right steering: when external force causes the shift fork 54 to press the reverse clutch pressure plate 510, the reverse clutch assembly 53 is in working condition, and the brake shaft 5 rotates driven by the reverse clutch. Since the power transmitted to the reverse gear 71 is one level higher than the power of the middle transmission gear 76, the rotation directions of the reverse gear 71 and the intermediate transmission gear 76 are opposite, and the reverse gear 71 rotates in the opposite direction relative to the intermediate transmission gear 76. The reverse gear 71 drives the reverse transmission shaft 7 to reverse through the spline, and the right steering wheel 712 also rotates in the opposite direction, and the right drive gear 79 also rotates in the opposite direction, and the left drive gear 74 rotates forward, thereby realizing the forward rotation of the left track and the reverse rotation of the right track, and realizing the in-situ steering or small radius steering of the machine.

[0088] Braking: In the braking steering mode, external force acts on the left steering fork and the right steering fork at the same time to separate the left driving gear 74, the right driving wheel 79 and the intermediate transmission gear 76, and respectively mesh with the reverse gear 71 and the right steering wheel 712 to achieve braking.

[0089] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A dual-mode gearbox with in-situ steering and single-side braking steering, comprising a housing (10) and a drive assembly and a speed transmission assembly installed in the housing (10), wherein the drive assembly comprises a left drive shaft assembly for realizing left steering and a right drive shaft assembly for realizing right steering, and the speed transmission assembly comprises a power input shaft assembly, a reverse gear shaft assembly and an auxiliary speed transmission shaft assembly, characterized in that: It also includes a reverse and brake assembly, which includes a brake shaft (5), and a reverse driving gear (51), a reverse clutch gear (52), a reverse clutch assembly (53), a shift fork (54) and a brake assembly (55) which are sequentially mounted on the brake shaft (5); the reverse clutch gear (52) is constantly meshed with a corresponding gear in the reverse gear shaft assembly, the reverse clutch gear (52) is mounted on the brake shaft (5) via a bearing, and the reverse clutch assembly (53) is fixed on the reverse clutch gear (52); The drive assembly further comprises a countershaft assembly, the countershaft assembly comprising a countershaft (7) and a counter gear (71), a left drive gear assembly, an intermediate transmission gear (76) and a right drive gear assembly which are sequentially mounted on the countershaft (7); the left drive gear assembly is provided with a left steering fork (75) which can control the left drive gear assembly to slide along the countershaft (7); the right drive gear assembly is provided with a right steering fork (78) which can control the right drive gear assembly to slide along the countershaft (7); the countershaft gear (71) is meshed with the counter driving gear (51); the left drive gear assembly is meshed with a corresponding gear on the left drive shaft assembly, and the right drive gear assembly is meshed with the right drive shaft assembly; the intermediate transmission gear (76) is constantly meshed with a corresponding gear on the auxiliary transmission shaft assembly; The left driving gear assembly comprises a left return spring (73) and a left driving gear (74); one end of the left return spring (73) is sleeved in the left driving gear (74), and the other end is in contact with a first bearing (72) provided in the counter gear (71); one end of the left driving gear (74) away from the left return spring (73) is connected to the intermediate transmission gear (76); The power input shaft assembly comprises an input shaft (1) and a third gear driving gear (11), a reverse gear driving gear (12), a second gear driving gear (13) and a first gear driving gear (14) which are sequentially mounted on the input shaft (1); the first gear driving gear (14) slides along the input shaft (1); The reverse clutch assembly (53) comprises a reverse clutch cover (56), a reverse clutch friction plate (57), a reverse clutch steel plate (58), a reverse clutch spline hub (59) and a reverse clutch pressure plate (510), wherein the reverse clutch cover (56) and the reverse clutch pressure plate (510) are combined to form a cavity, and within the cavity, the reverse clutch steel plate (58) is mounted on the brake shaft (5) via the reverse clutch spline hub (59); the brake assembly (55) has the same structure as the reverse clutch assembly (53), and the two are symmetrically arranged; the brake assembly (55) is mounted on the housing (10) at a side away from the reverse clutch assembly (53); The left drive shaft assembly comprises a left output shaft (8) and a left gear (81) mounted on the left output shaft (8); the right drive shaft assembly comprises a right output shaft (9) and a right gear (91) mounted on the right output shaft (9); the left gear (81) meshes with the left drive gear (74), and the right gear (91) meshes with the right drive gear (79).

2. The dual-mode transmission with in-situ steering and one-side brake steering according to claim 1, characterized in that: The right driving gear assembly comprises the right driving gear (79), a right return spring (710) and a right rotating wheel (712); one end of the right driving gear (79) is connected to the intermediate transmission gear (76), and the other end is provided with the right return spring (710); the right rotating wheel (712) is arranged at intervals beside the right driving gear (79); a second bearing (711) is arranged in the right rotating wheel (712), and the second bearing (711) abuts against the right return spring (710); The left drive gear (74) and the right drive gear (79) can respectively rotate and slide freely along the countershaft (7); the left drive gear (74) is meshed with a corresponding gear on the left drive shaft assembly, and the right drive gear (79) is meshed with the right drive shaft assembly.

3. The dual-mode transmission with in-situ steering and single-side brake steering according to claim 2, characterized in that: The end side of the left driving gear (74) is provided with a toothed insert that is pressed into engagement with the end side of the counter gear (71); the end side of the right driving gear (79) is provided with a toothed insert that is pressed into engagement with the end side of the right rotating wheel (712).

4. The dual-mode transmission with in-situ steering and single-side brake steering according to claim 2, characterized in that: Internal teeth are provided on both sides of the intermediate transmission gear (76); external teeth meshing with the internal teeth on one side of the intermediate transmission gear (76) are provided on the outer circumferential surface of the left drive gear (74); and external teeth meshing with the internal teeth on the other side of the intermediate transmission gear (76) are provided on the outer circumferential surface of the right drive gear (79).

5. The dual-mode transmission with in-situ steering and single-side brake steering according to claim 2, characterized in that: The counter gear (71) and the right-turning wheel (712) are respectively mounted on the counter shaft (7) via splines or flat keys; the intermediate transmission gear (76) is mounted in the middle of the counter shaft (7) via a bearing or a steel sleeve.

6. The dual-mode transmission with in-situ steering and one-side brake steering according to claim 1, characterized in that: The speed transmission assembly further comprises a shift shaft assembly, the shift shaft assembly comprising a shift shaft (2) and a third gear and reverse gear shift gear (21), a second gear driven gear (22), a secondary speed driving gear (23) and a first gear driven gear (24) which are sequentially mounted on the shift shaft (2); the third gear and reverse gear shift gear (21) slides along the shift shaft (2), and when sliding, the third gear and reverse gear shift gear (21) meshes with the third gear driving gear (11), or the third gear and reverse gear shift gear (21) meshes with the reverse gear driving gear (12); when the second gear driving gear (13) slides, it meshes with or does not mesh with the second gear driven gear (22); The reverse gear shaft assembly comprises a reverse gear shaft (3) and a reverse gear intermediate gear (31) mounted on the reverse gear shaft (3); The auxiliary speed change shaft assembly comprises an auxiliary speed change shaft (4), and an auxiliary speed change shift gear (41) and an auxiliary speed change low-speed gear driven gear (42) which are sequentially mounted on the auxiliary speed change shaft (4); the auxiliary speed change shift gear (41) slides along the auxiliary speed change shaft (4) so ​​as to mesh with the auxiliary speed change low-speed gear driven gear (42) or mesh with the second-speed gear driven gear (22); the intermediate transmission gear (76) is constantly meshed with the auxiliary speed change shift gear (41); The second gear driven gear (22) is constantly meshed with the second gear driving gear (13); the auxiliary speed driving gear (23) is constantly meshed with the auxiliary speed low speed driven gear (42); the reverse gear intermediate gear (31) is constantly meshed with the third gear and reverse gear shift gear (21); the reverse gear intermediate gear (31) is constantly meshed with the reverse gear driving gear (12); and the reverse gear intermediate gear (31) is constantly meshed with the reverse clutch gear (52).

7. The dual-mode transmission with in-situ steering and one-side brake steering according to claim 6, characterized in that: The auxiliary low-speed gear driven gear (42) is mounted on the auxiliary speed change shaft (4) via a bearing, and the auxiliary low-speed gear driven gear (42) is provided with internal teeth, which mesh with part of the external teeth of the auxiliary speed change gear (41).

8. The dual-mode transmission with in-situ steering and one-side brake steering according to claim 1, characterized in that: The reverse gear (71) is meshed with the reverse driving gear (51) via a reverse transfer gear (61), and the reverse transfer gear (61) is mounted on the box body (10) via a reverse transfer shaft (6).

Images