Double-clutch engine of straddle type vehicle

Abstract

The present invention relates to a dual clutch engine of a straddle type vehicle, comprising: a first clutch and a second clutch disposed on both left and right sides of an engine case; the main shaft comprises a first input shaft and a second input shaft which are separated from each other and coaxially arranged, the first clutch is connected with the first side of the first input shaft, the second clutch is connected with the second side of the second input shaft, and the first input shaft and the second input shaft are integrally located between the first clutch and the second clutch. According to the scheme, the layout of the first clutch, the second clutch and the gear shifting gear pair is improved, so that troubleshooting is facilitated.

Description

Technical Field

[0001] The present invention relates to the technical field of driving force of a straddle-type vehicle, and in particular to a dual-clutch engine of a straddle-type vehicle. Background Art

[0002] Most motorcycle engines currently sold on the market use a single-clutch structure, with a single shift drum controlling limited gears. This type of gear shifting causes a strong sense of jerkiness when switching gears, and the driving experience is poor.

[0003] Some of them also use dual-clutch engines. As disclosed in the prior art with publication number CN102297247B, people are well aware of the following dual-clutch transmission device: a first clutch and a second clutch for cutting off or engaging the engine power are respectively arranged on a first input shaft (inner shaft) and a second input shaft (outer shaft) arranged coaxially, and a plurality of gear sets for speed change are arranged between the first input shaft, the second input shaft and the output shaft, and the first clutch and the second clutch are alternately cut off or engaged to realize the speed change function.

[0004] In the above-mentioned single-side combined dual-clutch engine, the first input shaft and the second input shaft are nested inside and outside and need to drive different speed gear sets to realize the speed change function. The installation structure is complicated. If a fault occurs, it is not convenient to troubleshoot the fault due to the complicated installation structure. In particular, when one of the clutches fails, the entire engine casing needs to be disassembled for troubleshooting. If parts need to be replaced, the corresponding main shafts and gears of the two clutches need to be completely disassembled and assembled. When a fault occurs, it is difficult to repair and the repair cost is high.

[0005] In addition, in terms of clutch lubrication, most motorcycle clutches currently sold on the market are dry clutches or wet clutches. When the dry clutch is in a semi-clutch state, the friction of the clutch plate is more serious. Overall, it has a shorter life than the wet clutch; the wet clutch can be lubricated, but due to long-term intrusion into the lubricant, there is a certain degree of loss of engine power. The above traditional clutch systems all have shortcomings. Summary of the invention

[0006] In order to solve the above problems, the purpose of the present invention is to provide a dual-clutch engine for a straddle-type vehicle, and to improve the layout of the first clutch, the second clutch and the shift gear pair to facilitate troubleshooting.

[0007] A dual clutch engine for a straddle-type vehicle, comprising: A first clutch and a second clutch for cutting off or connecting the engine power, the first clutch and the second clutch are arranged on the left and right sides of the engine case; The main shaft includes a first input shaft and a second input shaft that are separated from each other and coaxially arranged, the first clutch is connected to a first side of the first input shaft, the second clutch is connected to a second side of the second input shaft, and the first input shaft and the second input shaft are integrally located between the first clutch and the second clutch; The countershaft is arranged parallel to the main shaft, and the main shaft and the countershaft are provided with gear pairs that cooperate with each other to form a plurality of different gear shift positions; A first shift drum, driven by a first shift motor, drives a plurality of shift forks connected to the first shift drum to switch the engagement state of the odd-numbered shift gear pairs; The second shift drum is driven by the second shift motor to drive a plurality of shift forks connected to the second shift drum to switch the engagement state of the even-numbered shift gear pairs.

[0008] Preferably, the output shaft of the first shift motor, the rotating shaft of the first shift drum and the main shaft are arranged parallel to each other, the first shift drum is located on the side of the main shaft close to the first clutch, and the first shift motor and the rotating shaft of the first shift drum are connected by a reduction gear group; the output shaft of the second shift motor, the second shift drum and the main shaft are arranged parallel to each other, the second shift drum is located on the side of the main shaft close to the second clutch, and the second shift motor and the rotating shaft of the second shift drum are connected by a reduction gear group; the connecting end of the first shift drum and the reduction gear group is close to the first clutch, and the connecting end of the second shift drum and the reduction gear group is close to the second clutch.

[0009] Preferably, a gear position sensor for detecting the current gear position is provided between the first gear shift drum and the second gear shift drum.

[0010] Preferably, the gear position sensor includes a rotor and a housing, the rotor includes a magnet, the housing is installed between the first gear shift drum and the second gear shift drum, the two rotors are respectively installed on the rotating shafts of the first gear shift drum and the second gear shift drum and are arranged toward the housing, and the rotation angles of the two gear shift drums are detected by cooperating with the two magnets through the same housing.

[0011] Preferably, the engine case includes a detachable first side cover and a detachable second side cover, the first clutch is located in the first side cover, and the second clutch is located in the second side cover.

[0012] Preferably, the engine case also includes a bottom shell, a first upper shell and a second upper shell that are detachably connected to each other, the bottom shell is divided into a first half and a second half along the axial direction of the main shaft, the first input shaft and the odd-numbered gear shifting gear pair are located in the installation space formed by the first half of the bottom shell and the first upper shell, and the second input shaft and the even-numbered gear shifting gear pair are located in the installation space formed by the second half of the bottom shell and the second upper shell.

[0013] Preferably, at least two support plates are provided on the engine case corresponding to the first input shaft and the second input shaft respectively. The at least two support plates are located at both ends of the first input shaft or the second input shaft in the axial direction and are provided with bearings for mounting the first input shaft or the second input shaft.

[0014] Preferably, it also includes: a fuel injection pump and an ECU. Fuel injection pumps are respectively arranged on the engine housing corresponding to the first clutch and the second clutch. The fuel injection nozzles of the fuel injection pumps are aimed at the clutch plate gaps of the corresponding clutches. The ECU is used to control the corresponding fuel injection pumps to inject fuel into the clutch plate gaps of the clutches during clutch action.

[0015] Preferably, a detection device for detecting whether the clutch is in an engaged state or a disengaged state is included, wherein the detection device is connected to an ECU, and the ECU is used for controlling an injection pump corresponding to the clutch to inject oil when the clutch is in a disengaged state.

[0016] Preferably, the fuel injection nozzle of the fuel injection pump is located directly above the corresponding clutch.

[0017] Due to the above scheme, the present invention places the first clutch and the second clutch on opposite sides of the engine housing, splits the main shaft into two independent first input shafts and second input shafts, and arranges them in a straight line side by side and separated from each other between the two clutches. The shift gear pairs on the first input shaft and the second input shaft can be arranged regularly and orderly, so that the clutch and the shift gear pair do not need to be disassembled to conveniently perform maintenance. In addition, the first clutch controls the odd-numbered gear position, and the second clutch controls the even-numbered gear position. The first shift drum and the first shift motor cooperate with the first clutch to automatically switch the odd-numbered gear position, and the second shift drum and the second shift motor cooperate with the second clutch to automatically switch the even-numbered gear position, so that gapless shifting can be achieved; and the two shift drums are independently controlled by the two shift motors, and the two shift drums can act simultaneously, so that the shift gap can be further shortened and the smoothness of the shifting can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a schematic diagram of the installation structure of this application; Figure 2 This is a transmission schematic diagram of this application; Figure 3 It is a transmission structure diagram of the gear-changing motor; Figure 4 Schematic diagram of the fuel injection pump setting position; Figure 5 for Figure 4 Schematic diagram of the structure after hiding part of the engine case.

[0019] Reference numerals: 1st clutch 1, 2nd clutch 2, 1st shift motor 031, 2nd shift motor 032, reduction gear set 4, 1st shift drum 5, 2nd shift drum 6, shift fork shaft 7, shift fork 8, 1st input shaft 9, 2nd input shaft 10, 6th speed drive gear 13, 4th speed drive gear 14, 8th speed drive gear 15, 2nd speed drive gear 16, 7th speed drive gear 17, 3rd speed drive gear 18, 5th speed drive gear 19, 1st speed drive gear 20, countershaft 21, 1st speed driven gear 22, 5th speed Driven gear 23, 3rd speed driven gear 24, 7th speed driven gear 25, 2nd speed driven gear 26, 8th speed driven gear 27, 4th speed driven gear 28, 6th speed driven gear 29, countershaft output gear 30, output transition gear 31, output shaft 33, small sprocket 34, gear position sensor 35, rotor 351, bottom shell 41, first side cover 42, second side cover 43, first upper shell 44, second upper shell 45, support plate 46, bearing 47, fuel injection pump 51, fuel injection nozzle 52, and fuel inlet pipe 53. DETAILED DESCRIPTION

[0020] The embodiments of the present invention are described in detail below.

[0021] This embodiment discloses a dual-clutch engine for a straddle-type vehicle, comprising a first clutch 1 and a second clutch 2 for cutting off or combining engine power. Figure 1 and Figure 2 As shown, the first clutch 1 and the second clutch 2 are arranged on the left and right sides of the engine case.

[0022] like Figure 2 As shown, the dual clutch engine includes: a main shaft composed of a first input shaft 9 and a second input shaft 10; a secondary shaft arranged parallel to the main shaft; a shift gear pair arranged across the main shaft and the secondary shaft; the first clutch 1 and the second clutch 2 coaxially arranged at the left and right ends of the main shaft; and a hydraulic supply device for supplying working hydraulic pressure to the first clutch 1 and the second clutch 2. The ECU cooperates with the hydraulic supply device to control the operation of the first clutch 1 and the second clutch 2.

[0023] Different from the dual-clutch engine in the prior art, the first input shaft 9 and the second input shaft 10 of the main shaft of this embodiment are separated from each other and coaxially arranged, the first clutch 1 is connected to the first side of the first input shaft 9, the second clutch 2 is connected to the second side of the second input shaft 10, and the first input shaft 9 and the second input shaft 10 are located between the first clutch 1 and the second clutch 2 as a whole. Specifically, the second input shaft 10 is located on the extension line of the first input shaft 9, and there is no inner and outer nesting relationship between the two. According to the switching of the first clutch 1 and the second clutch 2 cutting off or combining the engine power state, the first clutch 1 drives the first input shaft 9 to rotate or the second clutch 2 drives the second input shaft 10 to rotate to realize the power transmission of the engine. The first input shaft 9 and the second input shaft 10 are equipped with a plurality of driving gears 13-20 in the gearshift gear pair, and the secondary shaft is equipped with a plurality of driven gears 21-29 in the gearshift gear pair. Each driving gear 13-20 and the driven gear 21-29 are meshed with each other between each gearshift position to form a gearshift gear pair corresponding to each gearshift position.

[0024] In a specific embodiment, the dual-clutch engine realizes 1-n speed gear shifting, where n is an even number, so that the first clutch 1 is used to control the odd-numbered gears, and the second clutch 2 is used to control the even-numbered gears, so as to shorten the shifting gap. In order to realize the above-mentioned gear control, in this embodiment, the driving gears 17-20 for realizing the odd-numbered gear ratio are arranged on the first input shaft 9, and the driving gears 13-16 for realizing the even-numbered gear ratio are arranged on the second input shaft 10. Taking the dual-clutch engine realizing 1-8 speed gear shifting as an example, the driving gears 17-20 for realizing the 1st, 3rd, 5th, and 7th speed gear ratios in the multiple gear shifting gear pairs are arranged on the first input shaft 9, and the driving gears 13-16 for realizing the 2nd, 4th, 6th, and 8th speed gear ratios are arranged on the second input shaft 10.

[0025] The secondary shaft is arranged parallel to the main shaft, and the driven gear thereon corresponds to the driving gear one by one. The clutch controls upshifting and downshifting by switching the gear pair of the corresponding gear. In simple terms, the driving gear and the driven gear of the gear pair include a free gear and a spline gear. The free gear can rotate freely relative to the input shaft, and the free gear cannot directly transmit the rotation to the input shaft. The spline gear can directly transmit the power to the input shaft, and the spline gear can slide left and right along the axial direction of the input shaft. After the spline gear is connected to the free gear, the power can be transmitted according to the transmission ratio of the free gear to achieve gear shifting. The structure and principle of the gear switching between the driving gear and the driven gear are conventional technical means in the field, and will not be described in detail again. The main improvement of the present invention lies in the layout of the first clutch 1, the second clutch 2, the first input shaft 9, the second input shaft 10 and the gear pair. Through the above arrangement, the gear pairs of each gear are arranged in an orderly and regular manner between the two clutches, and the main shaft parts and the gear pair controlled by the two clutches are separated from each other, which is convenient for inspection and maintenance. Specifically, Figure 1 As shown, the first clutch 1 and the second clutch 2 are configured in the engine case as follows: the first clutch 1, the first input shaft 9, and the odd-numbered gear drive gear for the odd-numbered gears are arranged as a whole in the left half of the engine case, and the second clutch 2, the second input shaft 10, and the even-numbered gear drive gear for the even-numbered gears are arranged as a whole in the right half of the engine case.

[0026] Combination Figure 2 and Figure 3The dual-clutch engine includes an automatic shift mechanism, which includes a first shift drum 5, which is driven by a first shift motor 031, and drives a plurality of shift forks 8 connected to the first shift drum 5 to switch the engagement state of the odd-numbered shift gear pair; a second shift drum 6, which is driven by a second shift motor 032, and drives a plurality of shift forks 8 connected to the second shift drum 6 to switch the engagement state of the even-numbered shift gear pair. The first shift motor 031 and the second shift motor 032 are controlled by an ECU to achieve automatic shifting. One end of the shift fork 8 is slidably connected to a slideway on the outer periphery of the shift drum, and the other end of the shift fork 8 is arranged adjacent to a spline gear in the shift gear pair. When the shift drum rotates, the shift fork 8 connected thereto moves along the slideway where it is located, and the shape of the slideway is arranged to drive the shift fork 8 to drive the adjacent spline gear to move left and right in the axial direction to change the connection state between the spline gear and the adjacent sliding gear, thereby achieving gear switching. In this embodiment, the first shift drum 5 and the second shift drum 6 are respectively connected to a plurality of shift forks 8 to access the shift gear sets with different transmission ratios. In the above scheme of the present application, the first shift drum 5 and the first shift motor 031 cooperate with the first clutch 1 to automatically realize the shifting of odd gears, and the second shift drum 6 and the second shift motor 032 cooperate with the second clutch 2 to automatically realize the shifting of even gears, which can realize gapless shifting; and the two shift drums are independently controlled by the two shift motors, and the two shift drums can act at the same time, so as to further shorten the shifting gap and improve the smoothness of the shifting.

[0027] The countershaft is provided with a countershaft output gear 30, which rotates synchronously with the countershaft. The countershaft output gear 30 transmits power to the output shaft 33 through the output transition gear 31, and drives the small sprocket 34 thereon to rotate through the output shaft 33 to realize power output.

[0028] The shifting action of the dual-clutch engine of a straddle-type vehicle will be further explained below using 8-speed shifting as an example.

[0029] After the engine is started, the crankshaft transmission gear drives the first clutch 1 and the second clutch 2 on both sides to rotate. The clutch state of the electronically controlled clutch determines whether the clutch gears on both sides drive the first input shaft 9 and the second input shaft 10 to rotate. Figure 1 As shown in the figure, the red arrow on the left side indicates the power transmission path of the 1st gear, and the green arrow on the right side indicates the power transmission path of the 2nd gear. The following two examples are combined to illustrate the action process of shifting gears.

[0030] Example 1: The initial gear is N gear. During the process of shifting to 1 gear, the first clutch 1 is first switched to the disengaged state by the external action mechanism. The motorcycle ECU processes the upshift signal and gives the upshift power-on signal to the first shift motor 031. The first shift motor 031 drives the first shift drum 5 to rotate, causing the shift fork to slide to the left. The shift fork speed forces the transmission pin on the left side of the 5-speed driven gear 23 on the secondary shaft to connect to the 1-speed driven gear 22, so that the 1-speed driven gear 22 can rotate synchronously with the secondary shaft 21, and then the first clutch 1 is closed. At this time, the engine power transmission sequence is: engine crankshaft → clutch left gear → first clutch 1 → first input shaft → 1-speed driving gear 20 → 1-speed driven gear 22 → engine secondary shaft 21 → secondary shaft output gear 30 → output transition gear 31 → output shaft transmission gear → output shaft 33 → small sprocket 34.

[0031] Example 2: When switching to the 2nd gear, the second clutch 2 is switched to the disengaged state by the external action mechanism, the motorcycle ECU processes the upshift signal, gives the second shift motor 032 an upshift power-on signal, and the second shift motor 032 drives the second shift drum 6 to rotate so that the shift fork 8 shifts the 8th-speed driving gear 15, so that its left transmission pin is connected to the 2nd-speed driving gear 16, and then the first clutch 1 is switched to the disengaged state, and the second clutch 2 is switched to the engaged state. At this time, the engine power transmission sequence is: engine crankshaft→clutch right gear→second clutch 2→second input shaft→2nd-speed driving gear 16→2nd-speed driven gear 26→engine countershaft 21→countershaft output gear 30→output transition gear 31→output shaft transmission gear→output shaft 33→small sprocket 34.

[0032] like Figure 2 As shown, in order to simplify the installation structure of the shift fork 8, a shift fork shaft 7 parallel to the main shaft and the secondary shaft is provided between the two clutches in this embodiment, and all the shift forks 8 are installed on the shift fork shaft 7 together. The shift forks 8 can rotate relative to the shift fork shaft 7, so that when the shift drum drives other shift forks 8 to rotate around the shift fork shaft 7, the remaining shift forks 8 can remain in the current position.

[0033] like Figure 2As shown, in this embodiment, the output shaft 33 of the first shift motor 031, the rotating shaft of the first shift drum 5, and the main shaft are arranged in parallel with each other, the first shift drum 5 is located on the side of the main shaft close to the first clutch 1, and the first shift motor 031 and the rotating shaft of the first shift drum 5 are connected by a reduction gear set 4; the output shaft 33 of the second shift motor 032, the second shift drum 6, and the main shaft are arranged in parallel with each other, the second shift drum 6 is located on the side of the main shaft close to the second clutch 2, and the second shift motor 032 and the rotating shaft of the second shift drum 6 are connected by a reduction gear set 4, the connection end of the first shift drum 5 and the reduction gear set 4 is close to the first clutch 1, and the connection end of the second shift drum and the reduction gear set 4 is close to the second clutch 2. In this way, the two shift motors and the shift drums are arranged side by side and located between the two clutches, the automatic shift mechanism is located on one side of the shift gear pair as a whole, and the reduction gear set 4 is arranged close to the clutch, and the installation structure is compact.

[0034] In order to realize the speed control of the ECU, it is necessary to detect the current gear position. Therefore, in this embodiment, a gear position sensor 35 for detecting the current gear position is provided between the first gear shift drum 5 and the second gear shift drum 6. The current gear position is obtained by detecting the positions of the first gear shift drum 5 and the second gear shift drum 6. The gear position sensor 35 is arranged in this way, and no additional installation space is required. The gear position sensor 35 in this embodiment includes a rotor 351 and a housing. The rotor 351 includes a magnet. The housing is installed between the first gear shift drum 5 and the second gear shift drum 6. The two rotors 351 are respectively installed on the rotating shafts of the first gear shift drum 5 and the second gear shift drum 6 and are arranged toward the housing. The rotation angles of the two gear shift drums are detected by cooperating with the same housing and the two rotors. The above arrangement detects the rotation angles of the rotating shafts of the two gear shift drums through the same housing, and uses the same gear position sensor 35 to detect the gear shift drums on both sides, and the detection results are highly consistent.

[0035] The left and right sides of the engine housing are detachably connected with a first side cover 42 and a second side cover 43, which serve as clutch covers. The first side cover 42 is provided with a first clutch 1, and the second side cover 43 is provided with a second clutch 2. Figure 1The first side cover 42 and the second side cover 43 are respectively fixed in a detachable manner by multiple bolts, so as to facilitate the maintenance of the clutch. The engine housing also includes a bottom shell 41, a first upper shell 44 and a second upper shell 45 which are detachably connected to each other. The bottom shell 41 is divided into a first half and a second half along the axial direction of the main shaft. The first input shaft 9 and the odd-numbered gear shifting gear pair are located in the installation space formed by the first half of the bottom shell 41 and the first upper shell 44, and the second input shaft 10 and the even-numbered gear shifting gear pair are located in the installation space formed by the second half of the bottom shell 41 and the second upper shell 45. In this way, one or more of the first side cover 42, the second side cover 43, the first upper shell 44 and the second upper shell 45 can be opened according to the specific clutch and the specific gear shifting gear pair to be maintained. At least two support plates 46 are respectively provided on the engine case corresponding to the first input shaft 9 and the second input shaft 10. The at least two support plates 46 are located at the two ends of the first input shaft 9 or the second input shaft 10 in the axial direction, and bearings 47 for mounting the first input shaft 9 or the second input shaft 10 are provided thereon, so that the first input shaft 9 and the second input shaft 10 are respectively mounted by the two support plates 46 and the two bearings 47. In this embodiment, the installation of the first input shaft 9 is taken as an example. Support plates 46 are respectively provided at the two ends of the left half of the case close to the first input shaft 9. In an optional embodiment, the support plates 46 are detachably mounted in the engine case by a plurality of bolts; in another optional embodiment, the support plates 46 are integrally formed in the engine case. Further, optionally, a portion of a support plate 46 is arranged on the bottom shell 41, and another portion is arranged on the first upper shell 44. After the first upper shell 44 and the bottom shell 41 are installed, the support plates 46 on the bottom shell 41 and the first upper shell 44 are assembled into a complete support plate 46. The two ends of the first input shaft 9 are mounted on the support plates 46 by bearings 47. The installation of the second input shaft 10 refers to the first input shaft 9 .

[0036] In this embodiment, the first clutch 1 and the second clutch 2 are electronically controlled clutches, and are hydraulic clutches that cut off or connect the engine power by hydraulically controlling the pressure plate to shift in the axial direction. Figure 4 and Figure 5The dual clutch engine of this embodiment further includes an injection pump 51. The injection pump 51 is respectively arranged on the engine housing corresponding to the first clutch 1 and the second clutch 2. The injection nozzle 52 of the injection pump 51 is aimed at the clutch plate gap of the corresponding clutch; the ECU is used to control the corresponding injection pump 51 to spray oil into the clutch plate gap of the clutch during the clutch operation. During the clutch operation, the injection pump 51 sprays the lubricating oil into the clutch plate gap in the clutch through the injection nozzle 52, so that the clutch plate can be fully lubricated before the clutch is engaged, and the heat generated by the friction of the clutch plate can be transferred to the lubricating oil to the maximum extent, so that the service life of the clutch friction plate is extended; and compared with the wet clutch in the prior art, it is not necessary to immerse the part in the lubricating oil, and there can be less power loss. Therefore, the injection pump 51 has the advantages of both dry clutch and wet clutch according to the above arrangement, which not only ensures a higher power transmission efficiency, but also has the long service life of the wet clutch. The injection pump 51 in this embodiment is an electronic injection pump 51, and whether to spray oil is controlled by the ECU. The bottom of the engine case is an oil pan 41 for storing the refluxed engine oil. The oil inlet of the fuel injection pump 51 is connected to the oil pan 41 through the oil inlet pipe 53, and the engine oil in the oil pan 41 is extracted to be used as the lubricating oil for the clutch. The oil outlet of the fuel injection pump 51 nozzle 52 is located in the engine case and is aligned with the clutch plate gap of the corresponding clutch, so that the filtered lubricating oil enters the fuel injection pump 51 through the fuel inlet pipe 53 of the fuel injection pump 51, and enters the clutch plate gap through the fuel injection nozzle 52, and the fuel injection pump 51 can apply lubricating oil to the corresponding clutch.

[0037] In specific use, the fuel injection pump 51 can be detachably fixed on the engine case, and the fuel injection pump 51 and the fuel inlet pipe 53 are located outside the engine case, and the engine case is provided with an opening for the fuel injection nozzle 52 of the fuel injection pump 51 to extend into. In this way, the fuel injection pump 51 and the fuel inlet pipe 53 are externally arranged, and do not need to occupy the space in the engine case, which is convenient for maintenance. It is only necessary to set a structure for fixing the fuel injection pump 51 on the engine case. In a specific embodiment, according to the structure of the fuel injection pump 51 used, a structure for fixing the fuel injection pump 51 is set on the engine case. For example, a fixing seat matching the pump body shape of the fuel injection pump 51 is provided on the engine case, or the fuel injection pump 51 is provided with a threaded connection part, and a corresponding threaded connection hole is provided on the engine case.

[0038] In a preferred embodiment, the oil injection nozzle 52 of the oil injection pump 51 is located directly above the corresponding first clutch 1 and second clutch 2. Therefore, the lubricating oil sprayed by the oil injection nozzle 52 enters the clutch plate gap from directly above, and the coverage rate of the lubricating oil is relatively higher.

[0039] The above-mentioned embodiment structure of the present invention is easy to maintain and has the advantages of both dry clutch and wet clutch by improving the layout of the first clutch 1 and the second clutch 2 and improving the setting method of the clutch injection pump 51.

[0040] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A dual-clutch engine for a straddle-type vehicle, characterized in that: include: A first clutch and a second clutch for cutting off or connecting the engine power, the first clutch and the second clutch are arranged on the left and right sides of the engine case; The main shaft includes a first input shaft and a second input shaft that are separated from each other and coaxially arranged, the first clutch is connected to a first side of the first input shaft, the second clutch is connected to a second side of the second input shaft, and the first input shaft and the second input shaft are integrally located between the first clutch and the second clutch; The countershaft is arranged parallel to the main shaft, and the main shaft and the countershaft are provided with gear pairs that cooperate with each other to form a plurality of different gear shift positions; A first shift drum, driven by a first shift motor, drives a plurality of shift forks connected to the first shift drum to switch the engagement state of the odd-numbered shift gear pairs; The second shift drum is driven by the second shift motor to drive a plurality of shift forks connected to the second shift drum to switch the engagement state of the even-numbered shift gear pairs.

2. The dual clutch engine for a straddle-type vehicle according to claim 1, characterized in that: The output shaft of the first shift motor, the rotating shaft of the first shift drum, and the main shaft are arranged parallel to each other, the first shift drum is located on the side of the main shaft close to the first clutch, and the first shift motor and the rotating shaft of the first shift drum are connected by a reduction gear set; the output shaft of the second shift motor, the second shift drum, and the main shaft are arranged parallel to each other, the second shift drum is located on the side of the main shaft close to the second clutch, and the second shift motor and the rotating shaft of the second shift drum are connected by a reduction gear set; the connecting end of the first shift drum and the reduction gear set is close to the first clutch, and the connecting end of the second shift drum and the reduction gear set is close to the second clutch.

3. The dual clutch engine for a straddle-type vehicle according to claim 2, characterized in that: A gear position sensor for detecting the current gear position is arranged between the first gear shift drum and the second gear shift drum.

4. The dual clutch engine for a straddle-type vehicle according to claim 3, characterized in that: The gear position sensor includes a rotor and a shell. The rotor contains a magnet. The shell is installed between the first gear shift drum and the second gear shift drum. The two rotors are respectively installed on the rotating shafts of the first gear shift drum and the second gear shift drum and are arranged toward the shell. The rotation angles of the two gear shift drums are detected by cooperating with the two magnets through the same shell.

5. The dual clutch engine for a straddle-type vehicle according to claim 1, characterized in that: The engine case comprises a detachable first side cover and a detachable second side cover. The first clutch is located in the first side cover, and the second clutch is located in the second side cover.

6. The dual clutch engine for a straddle-type vehicle according to claim 5, characterized in that: The engine case also includes a bottom shell, a first upper shell and a second upper shell that are detachably connected to each other. The bottom shell is divided into a first half and a second half along the axial direction of the main shaft. The first input shaft and the odd-numbered gear shifting gear pair are located in an installation space formed by the first half of the bottom shell and the first upper shell, and the second input shaft and the even-numbered gear shifting gear pair are located in an installation space formed by the second half of the bottom shell and the second upper shell.

7. The dual clutch engine for a straddle-type vehicle according to claim 1, characterized in that: At least two support plates are respectively provided on the engine case corresponding to the first input shaft and the second input shaft. The at least two support plates are located at both ends of the first input shaft or the second input shaft in the axial direction and are provided with bearings for mounting the first input shaft or the second input shaft.

8. The dual clutch engine for a straddle-type vehicle according to claim 1, characterized in that: Also includes: A fuel injection pump and an ECU are provided on the engine housing corresponding to the first clutch and the second clutch, respectively, and the fuel injection nozzles of the fuel injection pumps are aimed at the clutch plate gaps of the corresponding clutches; the ECU is used to control the corresponding fuel injection pumps to inject fuel into the clutch plate gaps of the clutches during clutch action.

9. The dual clutch engine for a straddle-type vehicle according to claim 8, characterized in that: The invention comprises a detection device for detecting whether the clutch is in an engaged state or a disengaged state, wherein the detection device is connected to an ECU, and the ECU is used for controlling an injection pump corresponding to the clutch to inject oil when the clutch is in a disengaged state.

10. The dual clutch engine for a straddle-type vehicle according to claim 1, characterized in that: The injection nozzle of the fuel injection pump is located directly above the corresponding clutch.

Images