Transmission structure with wet clutch

Abstract

The utility model relates to a transmission structure with wet clutch, which is accommodated in a crankcase of an engine and driven by a cylinder head and a cylinder of the engine. The crankcase includes a left crankcase and a right crankcase. The transmission structure with wet clutch includes a crankshaft, a wet clutch and a drive shaft. The crankshaft is connected to a piston in the cylinder through a connecting rod. The wet clutch is sleeved on one end of the crankshaft and has oil flowing through the inside. The drive shaft is coaxial with the crankshaft and pivoted in the wet clutch, and can be selectively separated from or combined with the crankshaft under the control of the wet clutch. The right crankcase is provided with a clutch case shell, so that the wet clutch is accommodated in a clutch case chamber formed by the right crankcase and the clutch case shell. Thus, the performance stability can be improved, the shaking problem can be solved, the service life can be prolonged, the center of gravity of the vehicle can be moved forward, and the controllability can be improved.

Description

Technical Field

[0001] This utility model relates to a transmission structure with a wet clutch, and more particularly to a transmission structure with a wet clutch suitable for scooter motorcycles. Background Technology

[0002] In recent years, stringent environmental regulations and the energy crisis worldwide have prompted automakers to actively develop low-pollution, low-fuel-consumption, and high-performance engines. Among these technologies, high transmission efficiency is crucial for improving fuel economy and performance, effectively reducing power transmission losses. The wet clutch structure is one such high transmission efficiency technology, contributing to the achievement of low fuel consumption and high-performance engines.

[0003] Traditional mid-to-large scooters mostly use a dry clutch transmission structure due to their more affordable cost and simpler mechanical structure. Figure 1 This diagram illustrates a transmission structure with a dry clutch in a conventional mid-to-large-sized scooter. The transmission structure 900 with a dry clutch is housed in a crankcase 92 of an engine 91 and is driven by a cylinder head 911 and a cylinder 912 of the engine 91. The crankcase 92 includes a left crankcase 921 and a right crankcase 922. The dry clutch transmission structure 900 includes a crankshaft 913, a dry clutch 93, and an output shaft 98. The crankshaft 913 drives the output shaft 98 via the dry clutch 93, which in turn rotates a wheel 99. The dry clutch 93 is air-cooled, as shown by the air-cooling path W indicated by the arrow in the diagram. However, under heavy loads or excessive engine output, conventional mid-to-large-sized scooters experience overheating due to the limited effectiveness of air cooling, leading to unstable torque transmission and engine vibration. Therefore, the design of a wet clutch is a way to cool the engine oil, which improves the problem of high operating temperature, increases the torque capacity of the clutch, thereby improving performance stability, reducing vibration and extending service life.

[0004] In view of this, in response to the market demand for sporty handling, the recent product trend for mid-to-large-sized scooters is to combine a fixed engine with a wet clutch technology to achieve sporty handling similar to large-class motorcycles while also retaining the convenience of a scooter. Figure 2This diagram illustrates a conventional transmission structure with a wet clutch in a large-to-medium-sized scooter. The diagram shows a conventional transmission structure 900' with a wet clutch, including a crankshaft 913', a wet clutch 93', a continuously variable transmission (CVT) 95', and an output shaft 98'. The crankshaft 913' drives the output shaft 98' via the CVT 95' and the wet clutch 93' through a gear set 97', which in turn drives a wheel (not shown). However, the wet clutch 93' is located at the rear drive end of the CVT 951' of the engine, requiring a larger clutch and a more complex cooling system (oil reservoir 94' and oil path O'). This prevents a compact engine structure, thus limiting the provision of more storage space and the handling characteristics of a short wheelbase.

[0005] Driven by this, and in the spirit of active invention, the inventor sought a transmission structure with a wet clutch that could solve the above problems. After several research and experiments, the inventor finally completed this utility model. Utility Model Content

[0006] The main objective of this invention is to provide a transmission structure with a wet clutch. By placing the wet clutch at the front of the continuously variable transmission (CVT) drive shaft and housing it between the left crankcase and the clutch housing, the friction of the clutch plates is increased through engine oil cooling, achieving high torque capacity power output. This improves the smoothness of engine power engagement, prevents the vibration problem of dry clutches, and offers advantages such as better starting acceleration, sporty re-acceleration, less risk of burnout during two-person hill climbing, and longer service life. Furthermore, due to the front-mounted wet clutch, the transmitted torque is lower, allowing for a more compact engine mechanical structure and weight. Compared to existing technologies, this eliminates the need for additional mechanical space and saves on the space required for the clutch structure and complex cooling system. This also allows for a forward shift of the vehicle's center of gravity, resulting in larger storage space, shorter wheelbase handling, and better fuel economy.

[0007] To achieve the above objectives, this utility model provides a transmission structure with a wet clutch, housed within a crankcase of an engine and driven by a cylinder head and a cylinder of the engine. The crankcase includes a left crankcase and a right crankcase. The transmission structure with the wet clutch includes a crankshaft, a wet clutch, and a drive shaft. The crankshaft is connected to a piston in the cylinder via a connecting rod to convert the chemical energy of fuel into the kinetic energy of the crankshaft. The wet clutch is fitted onto one end of the crankshaft, and its interior is circulated with engine oil to cool the wet clutch and ensure a constant operating temperature. The drive shaft is coaxially mounted with the crankshaft and pivotally mounted within the wet clutch, and can be selectively disengaged or engaged with the crankshaft under the control of the wet clutch. The right crankcase is fitted with a clutch housing, allowing the wet clutch to be housed within a clutch chamber formed by the right crankcase and the clutch housing.

[0008] The aforementioned drive shaft can be driven by a continuously variable transmission to drive a transmission shaft, which in turn can drive an output shaft via a gear set. The output shaft can then drive a wheel to rotate, thereby propelling the vehicle forward.

[0009] The aforementioned clutch housing can be located between the wet clutch and the continuously variable transmission (CVT).

[0010] The aforementioned wet clutch can be a normally open type. When the crankshaft speed is less than a certain value, the drive shaft can be separated from the crankshaft. When the crankshaft speed reaches a certain value, the drive shaft can be engaged with the crankshaft.

[0011] The aforementioned wet clutch can be a multi-plate clutch.

[0012] The aforementioned wet clutch may include a clutch cover and a fixing plate fixed to the clutch cover by a buckle plate. Between the clutch cover and the fixing plate, there may be a plurality of rolling elements, a first clutch cover pressure plate, a clutch center guide, a plurality of clutch buffer plates, a plurality of clutch plates, a clutch friction plate, a second clutch cover pressure plate, a disc spring and a plurality of clutch springs, for performing the function of power transmission.

[0013] The aforementioned engine may be a fixed engine, locked to a fixed frame.

[0014] The aforementioned fixed frame may include a first right main frame, a second right main frame, a first right subframe, and a second right subframe surrounding the engine when viewed from the right side, and a first left main frame, a second left main frame, a first left subframe, and a second left subframe surrounding the engine when viewed from the left side, and the engine may be locked to the fixed frame at multiple locking points.

[0015] The above overview and the following detailed description are illustrative in nature and are intended to further illustrate the scope of the present invention. Other objects and advantages of the present invention will be described in the subsequent detailed embodiments and accompanying drawings. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the transmission structure with a dry clutch in a conventional medium-to-large scooter.

[0017] Figure 2 This is a schematic diagram of the transmission structure with a wet clutch in a conventional medium-to-large scooter.

[0018] Figure 3 This is a right-side view of a vehicle with a transmission structure featuring a wet clutch, according to a preferred embodiment of the present invention.

[0019] Figure 4 for Figure 3 AA sectional view.

[0020] Figure 5 This is an assembly diagram of a transmission structure with a wet clutch according to a preferred embodiment of the present invention.

[0021] Explanation of key component symbols:

[0022] 1 engine

[0023] 100 transmission structure

[0024] 11 cylinder head

[0025] 12-cylinder

[0026] 13 crankshaft

[0027] 14-link

[0028] 15-piston

[0029] 2 crankcases

[0030] 21 Left crankcase

[0031] 211 Left Crankcase Housing

[0032] 22 Right Crankcase

[0033] 221 Right Crankcase Housing

[0034] 3 wet clutch

[0035] 31 Clutch housing

[0036] 32 Clutch housing

[0037] 33 Clutch Cover

[0038] 34-panel

[0039] 35 fixed plate

[0040] 361 scrolling

[0041] 362 First Clutch Outer Cover Pressure Plate

[0042] 363 Clutch Center Guide

[0043] 364 clutch buffer plate

[0044] 365 clutch disc

[0045] 366 clutch friction plate

[0046] 367 Second Clutch Outer Cover Pressure Plate

[0047] 368 disc spring

[0048] 369 Clutch Spring

[0049] 4 drive shafts

[0050] 5-speed continuously variable transmission

[0051] 6 drive shafts

[0052] 7 gear sets

[0053] 71 Gearbox Housing

[0054] 8 output shafts

[0055] 9 wheels

[0056] 10 Fixed locking frame

[0057] 101 First Right Mainframe

[0058] 102 Second Right Mainframe

[0059] 103 First Right Subframe

[0060] 104 Second Right Subframe

[0061] 105 lock points

[0062] 900, 900' transmission structure

[0063] 91 Engine

[0064] 911 cylinder head

[0065] 912 cylinder

[0066] 913, 913' crankshaft

[0067] 92 crankcase

[0068] 921 left crankcase

[0069] 922 right crankcase

[0070] 93, 93' clutch

[0071] 94' oil storage chamber

[0072] 95' continuously variable transmission

[0073] 951' Continuously Variable Transmission

[0074] 97' gear set

[0075] 98, 98' output shaft

[0076] 99 wheels

[0077] O, O' oil path

[0078] R Mechanical Space

[0079] W air cooling path Detailed Implementation

[0080] Please see Figures 3 to 4 These are, respectively, the right side view of a vehicle with a transmission structure featuring a wet clutch according to a preferred embodiment of the present invention and... Figure 3 A cross-sectional view (AA) is shown in the figure. A transmission structure 100 with a wet clutch is shown, housed within a crankcase 2 of an engine 1 and driven by a cylinder head 11 and a cylinder 12 of the engine 1. The crankcase 2 includes a left crankcase 21 and a right crankcase 22. The transmission structure 100 of this invention includes a crankshaft 13, a connecting rod 14, a piston 15, a wet clutch 3, a drive shaft 4, a continuously variable transmission (CVT) 5, a transmission shaft 6, a gear set 7, and an output shaft 8. The right crankcase 22 is equipped with a clutch housing 31, which is located between the wet clutch 3 and the CVT 5, such that the wet clutch 3 is housed within a clutch chamber 32 formed by the right crankcase 22 and the clutch housing 31. Furthermore, the wet clutch 3 is fitted onto one end of the crankshaft 13, and its interior is circulated by oil from the cylinder head 11 or the crankshaft 13, as indicated by the arrow in the diagram, to cool the wet clutch 3 and ensure a constant operating temperature. The continuously variable transmission 5 is housed between the right crankcase 22 and a right crankcase housing 221. The gear set 7 is housed in a gearbox housing 71 and is located on the left side of the continuously variable transmission 5. In this embodiment, the engine 1 is a fixed-lock engine, which is locked to a fixed-lock frame 10. The fixed-lock frame 10 includes a first right main frame 101, a second right main frame 102, a first right subframe 103, and a second right subframe 104 surrounding the engine 1 when viewed from the right side, and a first left main frame (not shown), a second left main frame (not shown), a first left subframe (not shown), and a second left subframe (not shown) surrounding the engine 1 when viewed from the left side. The engine 1 is locked to the fixed-lock frame 10 with a plurality of locking points 105.

[0081] like Figure 3 and Figure 4As shown, the transmission structure 100 with a wet clutch in this embodiment transmits power as follows: the crankshaft 13 is connected to the piston 15 in the cylinder 12 via a connecting rod 14, which converts the chemical energy of the fuel explosion into the kinetic energy of the crankshaft 13. The drive shaft 4 is coaxially mounted with the crankshaft 13 and pivotally mounted in the wet clutch 3. It can be selectively disengaged from or engaged with the crankshaft 13 under the control of the wet clutch 3. The operation of the wet clutch 3 will be described in detail below. When the drive shaft 4 is disengaged from the crankshaft 13, the kinetic energy of the crankshaft 13 cannot drive the drive shaft 4. When the drive shaft 4 is engaged with the crankshaft 13, the kinetic energy of the crankshaft 13 can further drive the drive shaft 4. The drive shaft 4 drives the transmission shaft 6 via a continuously variable transmission 5. The transmission shaft 6 drives the output shaft 8 via a gear set 7. The output shaft 8 drives the wheels 9 to rotate, thereby driving the vehicle forward.

[0082] Please see Figure 5 This is an assembly diagram of the transmission structure with a wet clutch according to a preferred embodiment of the present invention. As shown in the figure, the wet clutch 3 in this embodiment is a multi-plate clutch, which includes a clutch cover 33 and a fixing plate 35 fixed to the clutch cover 33 by a buckle plate 34. Between the clutch cover 33 and the fixing plate 35 are sandwiched a plurality of rolling elements 361, a first clutch cover pressure plate 362, a clutch center guide 363, a plurality of clutch buffer plates 364, a plurality of clutch plates 365, a clutch friction plate 366, a second clutch cover pressure plate 367, a disc spring 368, and a plurality of clutch springs 369. In this embodiment, the wet clutch 3 is a normally open structure. When the rotational speed of the crankshaft 13 is less than a specific value, the drive shaft 4 is separated from the crankshaft 13. When the rotational speed of the crankshaft 13 reaches the specific value, the drive shaft 4 is engaged with the crankshaft 13. However, the present invention is not limited to this; the wet clutch 3 can also be a normally closed structure. Specifically, when the drive shaft 4 is disengaged from the crankshaft 13, the clutch cover 33 rotates freely, so the kinetic energy of the crankshaft 13 cannot drive the drive shaft 4; when the drive shaft 4 is engaged with the crankshaft 13, the kinetic energy of the crankshaft 13 is transmitted to the clutch cover 33 of the wet clutch 3. The clutch cover 33 drives multiple rolling elements 361, causing the multiple rolling elements 361 to be thrown apart by centrifugal force and push the first clutch cover pressure plate 362, thereby driving multiple clutch buffer plates 364, multiple clutch plates 365, clutch friction plates 366, the second clutch cover pressure plate 367, disc springs 368 and multiple clutch springs 369, buckle plate 34, fixing plate 35, and further transmitting the kinetic energy to the clutch center guide 363 and the drive shaft 4 to perform the function of power transmission.

[0083] Through the above design, the wet clutch 3 of the transmission structure 100 with wet clutch of this utility model can be placed in front of the drive shaft 4 of the continuously variable transmission 5 and housed between the right crankcase 22 and the clutch housing 31. Cooled by engine oil, the friction of the clutch plates is increased, achieving high torque capacity power output, thereby improving the smoothness of engine power engagement, preventing the problem of dry clutch vibration, and offering advantages such as better starting acceleration, sporty re-acceleration, less risk of burnout during two-person hill climbing, and longer service life. Furthermore, because the wet clutch 3 is front-mounted, its transmitted torque is smaller, allowing for a more compact mechanical structure and weight of the engine 1. Compared to existing technologies, it saves on additional mechanical space R and reduces the space required for the clutch structure and complex cooling system. Therefore, the vehicle's center of gravity can be shifted forward, resulting in larger storage space, shorter wheelbase handling, and better fuel economy.

[0084] The above embodiments are merely illustrative examples for ease of explanation. The scope of the rights claimed by this utility model should be determined by the scope of protection claimed in the patent application documents, and not limited to the above embodiments.

Claims

1. A transmission structure with a wet clutch, housed within a crankcase of an engine and driven by a cylinder head and a cylinder of the engine, the crankcase comprising a left crankcase and a right crankcase, characterized in that, The transmission structure with a wet clutch includes: A crankshaft connected to a piston inside the cylinder by a connecting rod; A wet clutch, fitted onto one end of the crankshaft and through which engine oil flows; and A drive shaft is coaxially mounted with the crankshaft and pivotally mounted in the wet clutch, and can be selectively separated from or engaged with the crankshaft under the control of the wet clutch; The right crankcase is equipped with a clutch housing, so that the wet clutch is housed in a clutch chamber formed by the right crankcase and the clutch housing.

2. The transmission structure with a wet clutch as described in claim 1, characterized in that, The drive shaft is driven by a continuously variable transmission (CVT) to drive a transmission shaft, which in turn drives an output shaft via a gear set, which in turn drives a wheel to rotate.

3. The transmission structure with a wet clutch as described in claim 2, characterized in that, The clutch housing is located between the wet clutch and the continuously variable transmission.

4. The transmission structure with a wet clutch as described in claim 1, characterized in that, The wet clutch is a normally open type. When the crankshaft speed is less than a certain value, the drive shaft is disengaged from the crankshaft. When the crankshaft speed reaches the certain value, the drive shaft is engaged with the crankshaft.

5. The transmission structure with a wet clutch as described in claim 1, characterized in that, This wet clutch is a multi-plate clutch.

6. The transmission structure with a wet clutch as described in claim 5, characterized in that, The wet clutch includes a clutch cover and a fixing plate fixed to the clutch cover by a buckle plate. Between the clutch cover and the fixing plate are a plurality of rolling elements, a first clutch cover pressure plate, a clutch center guide, a plurality of clutch buffer plates, a plurality of clutch plates, a clutch friction plate, a second clutch cover pressure plate, a disc spring and a plurality of clutch springs.

7. The transmission structure with a wet clutch as described in claim 1, characterized in that, The engine is a fixed-mount engine, locked to a fixed-mount frame.

8. The transmission structure with a wet clutch as described in claim 7, characterized in that, The fixed frame includes a first right main frame, a second right main frame, a first right subframe, and a second right subframe surrounding the engine when viewed from the right side, and a first left main frame, a second left main frame, a first left subframe, and a second left subframe surrounding the engine when viewed from the left side, and the engine is secured to the fixed frame by a plurality of locking points.

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