JP2007176415A - Compact vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To miniaturize a compact vehicle in the vertical direction, and to secure the minimum road clearance, while making an under-bone easy to ride over for an occupant, in regard to a compact vehicle of structure in which a car body frame provided with the under-bone frame, which is extended downward in rear from a head pipe, supports a power unit containing an engine and a V-belt type transmission arranged under the under-bone frame. <P>SOLUTION: A driven pulley 38 and a clutch 40 arranged on the same shaft with the driven pulley 38 structure one part of the V-belt type transmission 24, and they are arranged in front of a pivot shaft. An upper part of a part of a transmission case 28 for covering the V-belt type transmission 24, which covers the driven pulley 38 and the clutch 40, is arranged to be overlapped with the under-bone frame 7 with a view from a side surface. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an engine that is disposed below the underbone frame in a forward leaning posture on a vehicle body frame that includes a head pipe that supports the steering handle in a steerable manner and an underbone frame that extends rearwardly downward from the head pipe. A power unit including a V-belt type transmission is supported, and is driven by the power transmitted from the output shaft of the power unit at the rear part of the swing arm that is swingably supported by the body frame or the power unit via a pivot shaft. The present invention relates to a small vehicle on which a rear wheel is pivotally supported.

A power unit including a forward tilting engine and a V-belt transmission is suspended and supported by an underbone frame extending rearwardly downward from the head pipe, and the front portions of the pair of left and right swing arms that pivotally support the rear wheels at the rear portion are For example, Patent Document 1 discloses a motorcycle that is supported on a rear portion of a power unit so as to be swingable.
JP 2002-130440 A

  However, in the motorcycle disclosed in Patent Document 1, the power unit is arranged separately below the underbone frame, and it is difficult to say that the motorcycle is configured compactly in the vertical direction. For this reason, in order to ensure the minimum ground clearance, the position of the underbone frame must be set to a relatively high position, and the straddle height becomes relatively high when the passenger gets on and off.

  The present invention has been made in view of such circumstances, and provides a compact vehicle that can be made compact in the vertical direction so that a passenger can easily straddle an underbone frame while ensuring a minimum ground clearance. With the goal.

  In order to achieve the above object, the invention according to claim 1 is directed to a vehicle body frame including a head pipe that supports the steering handle so as to be steerable and an underbone frame that extends rearwardly downward from the head pipe in a leaning posture. A power unit including an engine and a V-belt transmission that is disposed below the underbone frame is supported, and the rear part of the swing arm that is swingably supported on the vehicle body frame or the power unit via a pivot shaft, In a small vehicle on which a rear wheel driven by power transmitted from an output shaft of a power unit is pivotally supported, the driven pulley can be switched between connection and disconnection of power transmission between the driven pulley and the output shaft. And a clutch arranged coaxially constitute a part of the V-belt transmission and the front An upper portion of the transmission case that is disposed in front of the pivot shaft and covers the V-belt type transmission and that covers the driven pulley and the clutch is disposed so as to overlap the underbone frame in a side view. Features.

  According to a second aspect of the present invention, in addition to the configuration of the first aspect of the invention, the V-belt type transmission is coaxially connected to the driven pulley and clutch, and the crankshaft of the engine. Also includes a drive pulley disposed in front, and an endless V-belt wound around the drive pulley and the driven pulley, and reduces the output of the driven pulley when the clutch is in a power transmission state. A gear reducer for transmitting to the output shaft is arranged between the crankshaft and the pivot shaft so that at least a part thereof overlaps the underbone frame in a plan view.

  According to the first aspect of the invention, it is possible to arrange the power unit at a relatively high position while avoiding interference with the underbone frame while setting the height of the underbone frame so that the occupant can easily straddle. The compact vehicle can be configured compactly in the vertical direction, and the minimum ground clearance can be secured.

  According to the invention described in claim 2, the small vehicle can be made more compact by effectively disposing the gear reducer in the empty space generated behind the crankshaft and below the underbone frame.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below based on one embodiment of the present invention shown in the accompanying drawings.

  1 to 3 show an embodiment of the present invention, FIG. 1 is a side view of a motorcycle, FIG. 2 is an enlarged sectional view taken along line 2-2 of FIG. 1, and FIG. 3 is 3-3 of FIG. It is a line expanded sectional view.

  In the following description of the embodiments, front and rear and left and right refer to directions in a state where the motorcycle is directed forward in the traveling direction.

  First, in FIG. 1, a body frame F of a motorcycle, which is a small vehicle, is a head pipe that supports a front fork 4 that pivotally supports a front wheel WF and a steering handle 5 that is connected to the upper portion of the front fork 4 so as to be steerable. 6, an underbone frame 7 extending rearwardly downward from the head pipe 6, a pivot plate 8 hanging downward from the rear end of the underbone frame 7, and right and left extending rearwardly from the rear portion of the underbone frame 7 A pair of seat rails 9 are provided, and a seat 10 for a passenger to sit on is provided on both seat rails 9.

  Of the vehicle body frame F, the underbone frame 7 and the pivot plate 8 have an engine E arranged in a forward tilted position below the underbone frame 7, and the output of the engine E is continuously variable and decelerated. A power unit P composed of a power transmission device T is supported, and a rear end portion of a pair of swing arms 12 and 12 is supported on the pivot plate 8 via a pivot shaft 11 so as to be swingable. The wheel WR is pivotally supported, and the output of the power unit P is transmitted to the rear wheel WR via a chain transmission means 13 shown in FIGS. 2 and 3 described later, and a rear cushion is provided between the swing arm 12 and the seat rail 9. 14 ... are provided.

  Further, the front of the head pipe 6 is covered with a front top cover 15, the rear of the head pipe 6 and the front part of the underbone frame 7 are covered with a frame top cover 16, and the sides of the underbone frame 7 are frame side covers 17. Leg shields 18 are arranged on both sides of the frame side covers 17 so as to cover the occupant's legs from the front and are connected to the front top cover 14, and below the frame side covers 17 are power units. An under cover 19 is provided continuously to cover P from the front.

  In FIG. 2, the crankcase 20 included in the engine E of the power unit P is formed by combining a left case half 20L and a right case half 20R, and a crankshaft 21 having an axis extending in the left-right direction is a ball bearing 22. , 23 through the crankcase 20 to be rotatably supported.

  The power transmission device T includes a V-belt transmission 24 that is a continuously variable transmission, and a gear reducer 25 that decelerates the output of the V-belt transmission 24. The gear transmission 25 is housed in the crankcase 20 and is housed in a transmission case 28 comprising an inner case 26 fastened to the right case half 20R and an outer case 27 coupled to the inner case 26 from the right side. It is stored in.

  A right end portion of the crankshaft 21 penetrates the inner case 26 rotatably and is inserted into the transmission case 28. An endless seal member 29 is interposed between the inner case 26 and the crankshaft 21. Be dressed. Further, the left end portion of the drive pulley shaft 31 is coaxially and non-rotatably coupled to the right end of the crankshaft 21 in the transmission case 28 and fixed to the left end portion of the drive pulley shaft 31 and the inner surface of the inner case 26. A ball bearing 33 is interposed between the ring-shaped bearing member 32 and the right end portion of the drive pulley shaft 31 is rotatably supported by the outer case 27 via the ball bearing 34. A driven pulley shaft 35 having an axis parallel to the crankshaft 21 and the drive pulley shaft 31 is disposed in the transmission case 28 behind the drive pulley shaft 31 and in front of the pivot shaft 11. The right end portion of the pulley shaft 35 is rotatably supported by the outer case 27 via a ball bearing 36.

  The V-belt type transmission 24 includes a drive pulley 37 attached to the drive pulley shaft 31 in the transmission case 28, a driven pulley 38 attached to the driven pulley shaft 35 in the transmission case 28, a drive pulley 37, An endless V-belt 39 wound around the driven pulley 38, and the driven pulley 38 and the driven pulley 38 are configured to transmit power from the driven pulley 39 to the driven pulley shaft 35 in response to the driven pulley 38 having a predetermined rotational speed or more. And a centrifugal clutch 40 provided between the driven pulley shafts 35.

  The drive pulley 37 is fixed to a portion of the drive pulley shaft 31 near the inner case 26, and is slidable in the axial direction of the drive pulley shaft 31 on the axially outer side of the fixed pulley half 41. The V belt 39 is wound around a V-shaped annular groove 43 formed between the pulley halves 41 and 42. A ramp plate 44 is fixed to the drive pulley shaft 31 on the back side of the movable pulley half 42, and a plurality of weight rollers 45 are accommodated in a floating state between the movable pulley half 42 and the ramp plate 44. Thus, when the rotational speed of the drive pulley shaft 31 increases as the rotational speed of the crankshaft 22 increases, the weight rollers 45 that receive centrifugal force move radially outward of the drive pulley shaft 31 to move the movable pulley half. 42 is brought close to the fixed pulley half 41. As a result, the contact radius of the V-belt 39 to both pulley halves 41 and 42 increases.

  Referring also to FIG. 3, the driven pulley 38 includes an inner cylinder 48 that allows relative rotation and coaxially surrounds the driven pulley shaft 35, and an inner cylinder that enables relative rotation around the axis and relative movement in the axial direction. An outer cylinder 49 in which 48 is slidably fitted, a fixed pulley half 50 fixed to the inner cylinder 48, and a movable pulley half 51 fixed to the outer cylinder 49 facing the fixed pulley half 50. The inner cylinder 48 and the outer cylinder 49 are configured so that an axial component force acts between the pulley halves 50 and 51 in accordance with the relative rotational phase difference between the movable pulley half 51 and the fixed pulley half 50. A torque cam mechanism 52 provided therebetween, and a coil spring 53 that elastically urges the movable pulley half 51 toward the fixed pulley half 50, and is formed between the fixed pulley half 50 and the movable pulley half 51. V V-belt 39 is wound on Jo annular groove 54.

  The centrifugal clutch 40 is disposed between the driven pulley 38 and the inner case 26 so as to be coaxial with the driven pulley 38, and includes a drive plate 55 fixed to the outer cylinder 49, and the drive plate 55. And a plurality of clutch weights attached to the drive plate 55 so as to be in frictional contact with the inner periphery of the clutch housing 56. 57.

  Thus, the distance between the fixed pulley half 50 and the movable pulley half 51 in the driven pulley 38 is the axial force generated by the torque cam mechanism 52, the axial elastic force generated by the coil spring 53, and the fixed pulley half. By determining the balance with the force from the V-belt 39 acting in the direction of separating the body 50 and the movable pulley half 51, the movable pulley half 42 is brought close to the fixed pulley half 41 in the drive pulley 37. When the winding radius of the V belt 39 around the drive pulley 37 increases, the winding radius of the V belt 39 around the driven pulley 38 decreases.

  Referring again to FIG. 2, the gear reducer 25 includes an input shaft 58 that is coaxially connected to the driven pulley shaft 35 and is relatively non-rotatable, and an output shaft 59 that is disposed coaxially with the input shaft 58. The right end portion of the input shaft 58 passes through the right case half 20R of the crankcase 20 and the inner case 26 of the transmission case 28 so as to be rotatable. The transmission case 28 is coaxially connected to the driven pulley shaft 35 and is relatively non-rotatable. A ball bearing 60 is interposed between the right case half 20R and the input shaft 58, and the input shaft 58 An annular seal member 61 is interposed between the inner cases 26.

  The output shaft 59 passes through the left case half 20L of the crankcase 20 in a rotatable manner, and a ball bearing 62 and a seal member 63 are interposed between the left case half 20L and the output shaft 59. In addition, the left end portion of the input shaft 58 is inserted coaxially with the output shaft 59 in the crankcase 20, and a pair of ball bearings 64 and 65 are interposed between the output shaft 59 and the left end portion of the input shaft 58. .

  Further, an intermediate shaft 66 having an axis parallel to the shafts 58 and 59 is disposed in front of the input shaft 58 and the output shaft 59, and both ends of the intermediate shaft 66 are connected to the crankcase 20. The left and right case halves 20L and 20R are rotatably supported via ball bearings 67 and 68.

  Thus, the gear reducer 25 includes a drive gear 71 formed integrally with the input shaft 58, a first idle gear 72 fixed to the intermediate shaft 66 so as to mesh with the drive gear 71, and the intermediate shaft 66. The second idle gear 73 formed integrally with the third idle gear 73 and the driven gear 74 formed integrally with the output shaft 59 so as to mesh with the third idle gear 73.

  A drive sprocket 75 is fixed to an outer end portion of the output shaft 59 protruding from the left case half 20l of the crankcase 20, and a chain 76 for transmitting power to the rear wheel WR is fixed to the drive sprocket 75. Is wound so as to constitute a part of the chain transmission means 13.

  Moreover, as clearly shown in FIG. 2, the gear reducer 25 is disposed between the crankshaft 21 and the pivot shaft 11, and at least a part thereof overlaps the underbone frame 7 of the vehicle body frame F in plan view. In the crankcase 20.

  Further, as clearly shown in FIG. 3, the upper part of the portion covering the driven pulley 38 and the clutch 40 in the transmission case 28 that covers the V-belt type transmission is in the underbone frame 7 only in the range A in a side view. Arranged overlapping.

  Next, the operation of this embodiment will be described. In the V-belt type transmission 24, the driven pulley 38 and the power transmission between the driven pulley 38 and the output shaft 59 can be switched, and arranged coaxially with the driven pulley 38. The clutch 40 is disposed in front of the pivot shaft 11, and the upper part of the portion covering the driven pulley 38 and the clutch 40 in the transmission case 28 covering the V-belt transmission 24 is underside in a side view. Since it is arranged so as to overlap the bone frame 7, the power unit P is arranged at a relatively high position while avoiding interference with the underbone frame 7 while setting the height of the underbone frame 7 so that an occupant can easily cross the bone frame 7. Therefore, the motorcycle can be configured compactly in the vertical direction, and a minimum ground clearance can be secured.

  The drive pulley 37 of the V-belt type transmission 24 is coaxially connected to the crankshaft 21 to reduce the output of the driven pulley 38 and transmit it to the output shaft 59 when the clutch 40 is in the power transmission state. Since the gear reducer 25 is disposed between the crankshaft 21 and the pivot shaft 11 so that at least a part of the gear reducer 25 overlaps the underbone frame 7 in plan view, it is located behind the crankshaft 21 and below the underbone frame 7. Thus, the motorcycle can be made more compact by effectively disposing the gear reducer 25 in the empty space generated in the above.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various design changes can be made without departing from the present invention described in the claims. It is.

  For example, the present invention can be applied to a small vehicle such as a motorcycle in which a swing arm is swingably supported on a power unit via a pivot shaft.

1 is a side view of a motorcycle. FIG. 2 is an enlarged sectional view taken along line 2-2 of FIG. FIG. 3 is an enlarged sectional view taken along line 3-3 in FIG. 1.

Explanation of symbols

5 ... Steering handle 6 ... Head pipe 7 ... Underbone frame 11 ... Pivot shaft 12 ... Swing arm 21 ... Crank shaft 24 ... V belt type transmission 25 ... Gear reducer 28 ... transmission case 37 ... drive pulley 38 ... driven pulley 39 ... V belt 40 ... clutch 59 ... output shaft E ... engine F ... body Frame P ... Power unit WR ... Rear wheel

Claims (2)

  The vehicle body frame (F) including a head pipe (6) that supports the steering handle (5) so as to be steerable and an underbone frame (7) that extends rearward and downward from the head pipe (6) is provided with a forward tilt posture. A power unit (P) including an engine (E) and a V-belt transmission (24) disposed below the underbone frame (7) is supported, and a pivot shaft is mounted on the vehicle body frame (F) or the power unit (P). A rear wheel (WR) driven by power transmitted from the output shaft (59) of the power unit (P) is pivotally supported at the rear part of the swing arm (12) supported so as to be swingable via (11). In such a small vehicle, the driven pulley (38) and the power transmission between the driven pulley (38) and the output shaft (59) can be switched. A clutch (40) disposed coaxially with the pulley (38) constitutes a part of the V-belt transmission (24) and is disposed in front of the pivot shaft (11). The upper part of the part which covers the said driven pulley (38) and the said clutch (40) among transmission case (28) which covers a transmission (24) overlaps with the said underbone frame (7) by side view. A small vehicle characterized by that.   The V-belt type transmission (24) is coaxially connected to the driven pulley (38) and the clutch (40) and the crankshaft (21) of the engine (E) and is more forward than the driven pulley (38). A drive pulley (37) disposed, and an endless V-belt (39) wound around the drive pulley (37) and the driven pulley (38), and the clutch (40) is in a power transmission state. Sometimes a gear reducer (25) for decelerating the output of the driven pulley (38) and transmitting it to the output shaft (59) at least partially overlaps the underbone frame (7) in plan view. The small vehicle according to claim 1, wherein the small vehicle is arranged between the crankshaft (21) and the pivot shaft (11).

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