Heavy-duty vehicle gearbox

Abstract

The invention discloses a gearbox for a heavy-duty vehicle, belonging to the field of gearboxes. The gearbox comprises an input shaft, an odd-numbered gear transmission shaft, an even-numbered gear transmission shaft and an output shaft, wherein an input gear is arranged on the input shaft, a transmission gear A and an odd-numbered gear set are arranged on the odd-numbered gear transmission shaft, the input gear is meshed with the transmission gear A and the transmission gear B respectively, a transmission gear B and an even-numbered gear set are arranged on the even-numbered gear transmission shaft, a driven gear set corresponding to the odd-numbered gear set and the even-numbered gear set is arranged on the output shaft, and the odd-numbered gear transmission shaft and the even-numbered gear transmission shaft are respectively provided with a first one-way clutch and a second one-way clutch. The invention adopts the method of not disconnecting the clutch first when shifting gears, but changing to a high gear while allowing the low gear to continue to operate to maintain the forward speed, and then disconnecting the low gear after the high gear operates normally, thereby avoiding the speed loss caused by the original method and smoothly realizing the switching from the low gear to the high gear.

Description

Technical Field

[0001] The present invention belongs to the technical field of gearboxes, and in particular, relates to a gearbox for a heavy-duty vehicle. Background Art

[0002] Agricultural machinery such as tractors, trucks and other load-bearing vehicles, construction machinery, etc., are mainly characterized by heavy loads and are not easy to shift. For example, tractors usually work in fields. Its gear shift is generally from low gear to high gear. First, use the first gear to start, then accelerate and step on the accelerator to make the engine reach a higher speed. When the engine speed is high, the output power margin is relatively large, so it is necessary to shift to a high gear. The existing manual transmission requires the clutch to be pressed, the engine and the output end are disconnected, the shift lever separates the low gear gear set, and then closes the high gear gear set, and then releases the clutch pedal to reconnect the engine and the output end.

[0003] However, since the tractor is very heavily loaded, once the clutch is pressed, the tractor's forward speed will drop rapidly, or even stop immediately, and the original inertia cannot maintain a high forward speed. In this case, shifting to the second gear will cause great damage to the gearbox. Normal operation requires re-engaging the first gear to start, which makes it difficult to use the appropriate gear during work, resulting in low speed and high rotation, wasting fuel, and low operating efficiency.

[0004] Cars usually travel on better roads and have lighter loads, so at the moment of clutch disconnection and gear shifting, the speed inertia is still relatively large, and the gear shift to a higher gear can still be carried out smoothly. Because of this feature, it is relatively easy to shift gears in cars. It is even common to see cars with automatic gear shifting, which does not require manual gear shifting. However, heavy-loaded vehicles rarely have automatic gear shifting. It is precisely because of this feature of such vehicles that the same automatic gear shifting technology is difficult to implement under such conditions. Summary of the invention

[0005] The invention aims to provide a heavy-duty vehicle gearbox to overcome the defects in the prior art that when the clutch of the heavy-duty vehicle gearbox is depressed, a new gear needs to be engaged to start the vehicle, resulting in wasted fuel and low operating efficiency.

[0006] The present invention is achieved by adopting the following technical solutions:

[0007] A heavy-duty vehicle gearbox comprises a power input shaft, an even-numbered gear transmission shaft, an odd-numbered gear transmission shaft and a power output shaft, wherein an input gear is arranged on the power input shaft, an odd-numbered gear set is arranged on the odd-numbered gear transmission shaft, and an even-numbered gear set is arranged on the even-numbered gear transmission shaft. The gearbox also comprises a transmission shaft A, a transmission shaft B, a first one-way clutch and a second one-way clutch, wherein a transmission gear A is arranged on the transmission shaft A, and a transmission gear B is arranged on the transmission shaft B, wherein the input gear meshes with the transmission gear A and the transmission gear B respectively, and an even-numbered gear driven gear set and an odd-numbered gear driven gear set corresponding to the odd-numbered gear set and the even-numbered gear set are arranged on the power output shaft, wherein the odd-numbered gear transmission shaft is connected to the transmission shaft A via a second one-way clutch, and the even-numbered gear transmission shaft is connected to the transmission shaft B via a first one-way clutch.

[0008] Furthermore, a reverse gear driving gear is fixedly provided on the even-numbered gear transmission shaft, a bridge gear assembled thereon through a bearing or a sleeve is provided on the odd-numbered gear transmission shaft, a reverse gear driven gear is provided on the output shaft, the reverse gear driving gear meshes with the bridge gear, and the bridge gear meshes with the reverse gear driven gear.

[0009] Furthermore, a synchronizer is provided between the driven gears of the even-numbered gear driven gear set and the driven gears of the odd-numbered gear driven gear set.

[0010] Furthermore, the odd-numbered gear set includes a 1st gear and a 3rd gear, and the even-numbered gear set includes a 2nd gear and a 4th gear.

[0011] Compared with the prior art, the beneficial effect of the present invention is that the present invention does not disconnect the clutch first when shifting gears, but instead allows the low gear to continue to operate to maintain the forward speed and then shifts to the high gear, and then disconnects the low gear after the high gear operates normally, thus avoiding the speed loss caused by the original method and smoothly realizing the switching from low gear to high gear. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a top view of the structural principle of the present invention;

[0013] Figure 2 It is a structural schematic diagram of the reverse gear in the present invention.

[0014] In the figure: 1. transmission shaft A; 2. transmission gear A; 3. power input shaft; 4. input gear; 5. transmission shaft B; 6. transmission gear B; 7. first one-way clutch; 8. 2nd gear; 9. 4th gear; 10. reverse gear driving gear; 11. even gear transmission shaft; 12. even gear driven gear set; 13. power output shaft; 14. synchronizer; 15. odd gear transmission shaft; 16. 3rd gear; 17. 1st gear; 18. bridge gear; 19. reverse gear driven gear; 20. second one-way clutch; 21. odd gear driven gear set. DETAILED DESCRIPTION

[0015] The present invention will be further described below in conjunction with the accompanying drawings.

[0016] like Figure 1 As shown, the heavy-duty vehicle gearbox of the present invention comprises a power input shaft 3, an even-numbered gear transmission shaft 11, an odd-numbered gear transmission shaft 15 and a power output shaft 13, an input gear 4 is arranged on the power input shaft 3, an odd-numbered gear set is arranged on the odd-numbered gear transmission shaft 15, and an even-numbered gear set is arranged on the even-numbered gear transmission shaft 11. The heavy-duty vehicle gearbox also comprises a transmission shaft A1, a transmission shaft B6, a first one-way clutch 7 and a second one-way clutch 20, a transmission gear A2 is arranged on the transmission shaft A1, a transmission gear B6 is arranged on the transmission shaft B5, the input gear 4 is respectively meshed with the transmission gear A2 and the transmission gear B6, an even-numbered gear driven gear set 12 and an odd-numbered gear driven gear set 21 corresponding to the odd-numbered gear set and the even-numbered gear set are arranged on the power output shaft 13, the odd-numbered gear transmission shaft 15 and the transmission shaft A1 are connected via the second one-way clutch 20, and the even-numbered gear shaft 11 and the transmission shaft B5 are connected via the first one-way clutch 7.

[0017] Among them, the first one-way clutch 7 and the second one-way clutch 20 are both one-way deep groove ball bearings, that is, they can only transmit in one direction. When the power source transmits the passive element, only one direction is transmitted. If the power source changes direction, such as clockwise to counterclockwise, the transmission work of the passive element will stop transmitting. The one-way clutch function of the first one-way clutch 7 and the second one-way clutch 20 is controllable. Only when the gear is shifted, the one-way clutch function is opened. In the normal operation state after the gear shift is completed, this function is closed. At this time, the function is exactly the same as that of an ordinary clutch. Sometimes a heavy truck needs to be put in a low gear when going downhill, and the engine is used to control the vehicle's sliding. This clutch can also complete it.

[0018] Further, such as Figure 2 As shown, a reverse gear driving gear 10 is fixedly provided on the even-numbered gear transmission shaft 11, a bridge gear 18 assembled thereon through a bearing or a sleeve is provided on the odd-numbered gear transmission shaft 15, a reverse gear driven gear 19 is provided on the output shaft 13, the reverse gear driving gear 10 is meshed with the bridge gear 18, and when the reverse gear is engaged, the bridge gear 18 is meshed with the reverse gear driven gear 19.

[0019] Furthermore, a synchronizer 14 is provided between the driven gears of the even-numbered gear driven gear set 12 and the odd-numbered gear driven gear set 21 .

[0020] Furthermore, the odd-numbered gear set includes the 1st gear 17 and the 3rd gear 16, and the even-numbered gear set includes the 2nd gear 8 and the 4th gear 9. The gearbox of this embodiment has four forward gears, and can also be designed as a structure with other gear numbers.

[0021] Working principle of the present invention:

[0022] The 1st gear set described below includes the 1st gear 17 and a driven gear corresponding to the 1st gear 17 , and the same is true for the 2nd gear set.

[0023] In neutral, the first one-way clutch 7 and the second one-way clutch 20, as well as the gear sets of each gear position, are all in a disengaged state, and no power is transmitted from the input end to the output end.

[0024] When starting from neutral, the 1st gear set is connected, and then the second one-way clutch 20 is closed, and the power of the power input shaft 3 is transmitted through the transmission shaft A1 and the odd-numbered gear transmission shaft 15, and then transmitted to the power output shaft 13 through the already connected 1st gear set.

[0025] When shifting from 1st gear to 2nd gear, the connection state of the 1st gear gear set and the second one-way clutch 20 remains unchanged, but at the same time the 2nd gear set is connected and the first one-way clutch 7 is connected. At this time, the power output shaft 13 has the power transmitted by the 1st gear set and the power transmitted by the 2nd gear set, and the speed transmitted by the 2nd gear set is higher than the speed transmitted by the 1st gear set. At this time, the role of the one-way clutch is reflected. The first one-way clutch 7 and the second one-way clutch 20 can both separate at both ends when the output end speed is greater than the input end speed. In the current situation, the second one-way clutch 20 is automatically separated because the output end speed is greater than the input end, so only the 2nd gear set is actually driven on the power output shaft 13. After the power output shaft 13 is driven by the 2nd gear set and operates normally, the second one-way clutch 20 is disconnected under the control of the operating mechanism, the 1st gear set is disconnected, and the shifting process is completed.

[0026] The other gear shifting processes to higher gears are the same.

[0027] When downshifting, the process is just the opposite of upshifting. For example, when downshifting from 2nd gear to 1st gear, first keep the 2nd gear gear set and the first one-way clutch 7 connected, then connect the 1st gear gear set and the second one-way clutch 20. Obviously, the output end is still driven by the 2nd gear set. At this time, the 2nd gear set and the first one-way clutch 7 are disconnected, and the connected 1st gear gear set and the second one-way clutch 20 start to work, and the speed is reduced to the 1st gear state.

[0028] When the gear is reversed, the output end has the opposite direction of rotation, so a bridge transmission is required. The input power is transmitted to the even-numbered gear transmission shaft 11, and then transmitted to the bridge gear 18 on the odd-numbered gear transmission shaft 15 by the reverse gear driving gear 10. The bridge gear 18 has no transmission effect on the odd-numbered gear transmission shaft 15, and is assembled on the odd-numbered gear transmission shaft 15 by bearings or sleeves, and only plays a supporting role. The bridge gear 18 then transmits the power to the power output shaft 13 through the reverse gear driven gear 19 to achieve reverse reverse gear.

[0029] Compared with the simple process of pressing the clutch, shifting the gear lever, and releasing the clutch during the ordinary clutch shifting process, the technology of the present invention is much more complicated and is not suitable for manual completion. Therefore, the starting point of this technology is to set up each step of the operation process and complete it with an electronic control system. The operator only needs to issue an instruction, and the electronic control system can complete each step of the operation in sequence until the gear shift is completed. Since there is electronic control, it is possible to automatically detect parameters such as engine speed, automatically increase or decrease gears, and realize automatic gears for this type of vehicle equipment, which further liberates the driving operator and improves comfort.

Claims

1. A heavy-duty vehicle gearbox, comprising a power input shaft (3), an even-numbered gear transmission shaft (11), an odd-numbered gear transmission shaft (15) and a power output shaft (13), wherein the power input shaft (3) is provided with an input gear (4), the odd-numbered gear transmission shaft (15) is provided with an odd-numbered gear set, and the even-numbered gear transmission shaft (11) is provided with an even-numbered gear set, characterized in that: The invention also comprises a transmission shaft A (1), a transmission shaft B (5), a first one-way clutch (7) and a second one-way clutch (20); the transmission shaft A (1) is provided with a transmission gear A (2); the transmission shaft B (5) is provided with a transmission gear B (6); the input gear (4) is meshed with the transmission gear A (2) and the transmission gear B (6) respectively; the power output shaft (13) is provided with an even-numbered gear driven gear set (12) and an odd-numbered gear driven gear set (21) corresponding to the odd-numbered gear set and the even-numbered gear set; the odd-numbered gear transmission shaft (15) is connected to the transmission shaft A (1) via the second one-way clutch (20); and the even-numbered gear transmission shaft (11) is connected to the transmission shaft B (5) via the first one-way clutch (7); A reverse gear driving gear (10) is fixedly provided on the even-numbered gear transmission shaft (11), a bridge gear (18) mounted thereon via a bearing or a sleeve is provided on the odd-numbered gear transmission shaft (15), a reverse gear driven gear (19) is provided on the power output shaft (13), and the reverse gear driving gear (10) is meshed with the bridge gear (18); A synchronizer (14) is provided between the driven gears of the even-numbered gear driven gear set (12) and the odd-numbered gear driven gear set (21); The odd-numbered gear set comprises a 1st gear (17) and a 3rd gear (16), and the even-numbered gear set comprises a 2nd gear (8) and a 4th gear (9).

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