JPH04201691A - Two-wheel drive motorcycle - Google Patents

Abstract

PURPOSE:To reduce the quantity of components, the area of a machining surface and cost by housing front and rear continuously variable V-belt transmissions, and front and rear centrifugal clutches respectively in a belt chamber constituted of a left side engine case and a clutch cover. CONSTITUTION:Right and left engine cases 3 and 2 are mated to each other and tightened at the section of a crank chamber 4. The section of the left engine case 2 outside the crank chamber 4 is extended up and aft approximately in an L-shape, and front and rear clutch shafts 6 and 7 are axially supported on the front and rear sides of a crankshaft 5. The clutch shafts 6 and 7 are fitted with centrifugal clutches 8 and 9, and continuously variable V-belt transmissions 10 and 11 are provided between and coupled to the crankshaft 5 and the centrifugal clutches 8 and 9. A clutch cover 12 is mated to the external side of the left engine case 2 and secured. The clutch shafts 6 and 7 are projected inside the left engine case 2, and coupled with gear reducers 13 and 14. In addition, gear reducers 15 and 16 are aligned with and secured to connection surfaces 17 and 18 formed at the inner side of the left engine case 2.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to a front and rear wheel drive motorcycle.

(Prior Art) Some motorcycles can run by driving both the front and rear wheels with an engine, which has the advantage of being able to run smoothly even on slippery roads such as sandy areas.

Generally, a motorcycle uses an engine to drive the rear wheels, and a front-wheel drive motorcycle is manufactured by adding a front wheel drive device to a motorcycle that drives the rear wheels.

(Problem to be solved by the invention) When a device for driving the front wheels is added to a motorcycle that uses an engine to drive the rear wheels, the engine case is divided into many parts, and there are many machining surfaces, resulting in high costs. It has become.

In view of these points, it is an object of the present invention to provide a front- and rear-wheel drive motorcycle that can be produced at low cost by having fewer components in the engine case and by reducing the number of parts during machining, thereby reducing casting and cutting costs. .

(Means for Solving the Problems) In order to achieve the above object, the front and rear wheel drive motorcycle of the present invention has an engine case that can be divided into left and right parts at the crank chamber portion, and a crank chamber portion of the left engine case. The outer side is shaped like an abbreviation and extends upward and rearward, and the front and rear clutch shafts are pivotally supported above and behind the crankshaft, and the front and rear centrifugal clutches are installed respectively between the crankshaft and the front and rear centrifugal clutches. The front and rear continuously variable belt transmissions are connected, a clutch cover is attached to the outer surface of the left engine case to form a belt chamber, and the front and rear clutch shafts are protruded inside the left engine case to reduce gears. The gear cases were connected and fastened to the inner side of the left engine case, and the output shafts of the front and rear gear reducers were connected to the front and rear wheels through a chain to drive them. It is in.

Another feature is that the connecting surfaces that connect the front and rear gear cases of the left engine case are formed at the same height from the engine center line.

(Function) When the crankshaft rotates, the front and rear continuously variable V-belt transmissions rotate in conjunction with each other, and as the crankshaft rotates, the continuously variable V-belt transmission rotates.
Belt transmission increases speed. When the rotation speed reaches a predetermined speed, the front and rear centrifugal clutches are connected, the front and rear clutch shafts begin to rotate, and the front and rear wheels are driven through the front and rear gear reducers, chains, etc., allowing the vehicle to travel. . The front and rear continuously variable V-belt transmissions and front and rear centrifugal clutches can be accommodated in the belt chamber, which consists of the left-hand engine case and clutch cover, and the front and rear gear cases with gear reducers installed are connected to the front and rear of the left-hand engine case. You can reduce the number of cases. Furthermore, by aligning the connecting surfaces that connect the front and rear gear cases of the left engine case, milling can be performed simultaneously, making the cutting process more efficient.

(Example) Embodiments of the present invention will be described below with reference to the drawings.

The engine 1 is a two-cycle engine, and left and right engine cases 2.3 are fitted together at 4 parts of the crank chamber and are fastened together. The engine case 2 on the left is the crank chamber 4
The outer part extends upward and backward in an abbreviated form. Front and rear clutch shafts 6.7 are supported on the upper and rear sides of the crankshaft 5. Front and rear centrifugal clutches 8.9 are attached to the front and rear clutch shafts 6.7, respectively. Between the crankshaft 5 and the front and rear centrifugal clutches 8.9, the front and rear continuously variable V-belt transmissions 10. Concatenate l'l. A clutch cover 12 is fitted and fastened to the outer surface of the left engine case 2. The front and rear clutch shafts 6.7 are made to protrude inside the left engine case 2, and are covered with gear reduction gears 13.14, respectively, and gear cases 15.16 are covered with the front and rear gear reduction gears 13.14, respectively. , front and rear gear case 1
5.16 to the connecting surface 17.18 provided on the inner surface of the left engine case 2 and tighten. Front and rear gear reducer 1
Sprockets 21.22 are attached to the ends of the output shafts 19.20 of 3.14, respectively, and are connected to and driven by the front wheels 25 and rear wheels 2B via chains 23, 24, etc.

The front and rear continuously variable V-belt transmissions 10.11 rotate in response to the rotation of the crankshaft 5 of the engine 1, and as the rotation of the crankshaft 5 increases, the front and rear continuously variable V-belt transmissions to, t rotate.
i automatically increases speed. When the rotation speed increases to a predetermined speed, the front and rear centrifugal clutches 8.9 are connected, the front and rear clutch shafts 6.7 begin to rotate, and the gear reducer 13.14 connects the front and rear centrifugal clutches 8.7 to rotate. Both the front wheels 25 and the rear wheels 2B can be driven to drive the vehicle.

The engine cases 2 and 3, the clutch cover 12, and the front and rear gear cases 15 and 16 are cast using light alloy, but the front and rear gear cases 1 are particularly small in number and machined.
5. Connecting surface 1 of left engine case 2 connecting 16
7.18 are aligned at the same height, so they can be cut at the same time by milling.

(Effects of the Invention) As explained above, since the present invention is configured as described above, the front and rear continuously variable V-belt transmissions and the front and rear centrifugal clutches are housed in the belt chamber composed of the left engine case and the clutch cover. This reduces the number of covers and machining surfaces, reducing casting and cutting costs. Furthermore, the left engine case and clutch cover that house the front centrifugal clutch can be made smaller without leaving large spaces inside or on the sides. By matching the height of the connecting surface where the gear case of the left engine case fits, and also matching the height of the gear reducer holding boss to the connecting surface, there is less need for end milling, and milling can be done once. can be finished.

[Brief explanation of the drawing]

The figures show an embodiment of the present invention; FIG. 1 is a longitudinally developed plan view of the engine; FIG. 2 is a side view of the engine with the clutch cover removed; and FIG. 3 is an overall side view. 2.3...Engine case, 4...Crank chamber, 5
...Crank To, 6. 7...Clutch shaft, 8.9
--Centrifugal clutch, 10. II...Continuous V-belt transmission, I2...Clutch cover, 13.14...
Gear reducer, 15.16...Gear case, 17.18
... Connection surface, 19.20 ... Output shaft, 23, 24.
...Chain, 25...front wheel, 26...rear wheel.

Claims (1)

[Claims] 1. The engine case can be divided into left and right parts at the crank chamber portion, and the outside of the left engine case from the crank chamber portion is extended upward and rearward in a substantially L-shape, and the upper and rear portions of the crankshaft are extended upward and rearward. The front and rear clutch shafts are pivotally supported on the sides, and the front and rear centrifugal clutches are installed respectively, and the front and rear continuously variable V-belt transmissions are connected between the crankshaft and the front and rear centrifugal clutches, and the clutch cover is installed on the outside of the left engine case. to form a belt chamber, the front and rear clutch shafts are protruded into the inside of the left engine case, a gear reducer is connected to each, and the gear cases are connected and tightened to the inside of the left engine case. A front and rear wheel drive motorcycle characterized in that the output shafts of the front and rear gear reduction gears are connected to the front wheels and the rear wheels respectively through a chain or the like. 2. The front and rear wheel drive motorcycle according to claim 1, wherein the connecting surfaces connecting the front and rear gear cases of the left engine case are formed at the same height from the engine center line.