JPH0411410B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION A. Object of the Invention (1) Field of Industrial Application The present invention relates to a power transmission device for a vehicle having a pair of left and right drive wheels.

(2) Prior Art A vehicle in which a pair of left and right belt-type automatic transmissions are interposed between an output shaft of an engine and a pair of left and right drive wheels, and both drive wheels are connected in parallel to the output shaft. The power transmission device is conventionally known as shown in FIG. 3 of Japanese Patent Laid-Open No. 50-52721, for example.

(3) Problems to be Solved by the Invention In the above-mentioned conventionally known transmissions, a pair of left and right belt-type automatic transmissions is provided with a differential function, so that a dedicated differential device can be omitted, and the structure of the power transmission device can be simplified. It has the advantage of being able to achieve

SUMMARY OF THE INVENTION An object of the present invention is to provide a power transmission device for a vehicle that takes advantage of the advantages of the conventional device while further simplifying the structure and contributing to miniaturization and cost reduction.

B. Structure of the Invention (1) Means for Solving the Problems In order to achieve the above object, the present invention provides a pair of left and right belt-type automatic transmissions between the output of the engine and a pair of left and right drive wheels. In a power transmission device for a vehicle in which both drive wheels are connected in parallel to the output shaft, the pair of left and right belt-type automatic transmissions are respectively housed in a pair of left and right transmission cases, and One end of each transmission case supports the drive pulley of the transmission, and the other end supports the driven pulley of the transmission, and the one ends of the pair of left and right transmission cases are connected to each other through the crankcase of the engine. The power unit case is integrally coupled to form a power unit case, and the power unit case is pivotally supported on the vehicle body frame so as to be able to swing vertically. A suspension device is interposed between the power unit and the vehicle body frame, and the pair of left and right The transmission case is characterized in that each drive wheel connected to a corresponding driven pulley is rotatably supported at each other end of the transmission case.

(2) Function In a pair of left and right belt-type automatic transmissions that can cooperate with each other to exhibit a differential function, each transmission case is also used as a swing arm member for suspending the pair of left and right drive wheels. . Further, the crankcase of the engine is also used as a reinforcing coupling member that integrates the pair of left and right swing arm members to reinforce each other. Furthermore, the shaft support of the power unit case to the vehicle body is shared by means for mounting the engine and transmission case to the vehicle body.

In addition, since the driving and driven pulleys of each automatic transmission are supported by one end and the other end of a common transmission case, the driving and driven pulleys of each automatic transmission are supported by one end and the other end of the common transmission case, respectively, so the driving and driven pulleys of each automatic transmission are supported by one end and the other end of the common transmission case.
The distance between the axes of the driven pulley is always kept constant, and the desired automatic speed change function is always effectively performed.

(3) Examples Examples of the present invention will be described below with reference to the drawings.

First, starting with the first embodiment shown in FIGS. 1 to 7, in FIGS. 1 to 3, the illustrated vehicle has a pair of left and right drive wheels Wf, Wf' at the front part of a body frame F. A power unit P for driving the vehicle is provided, and a driven wheel Wr is provided at the rear of the vehicle.

The vehicle body frame F has support plates 1a, 1 at each front end.
A pair of left and right vertical members 1, 1' with a' standing upright, and a plurality of horizontal members 2, 3, 4, which connect them in a ladder shape.
5, a pair of left and right reinforcing members 6, 6' that connect the two middle horizontal members 3, 4, and a pair of reinforcing members 6, 6' at the front, center and rear of these to connect the vertical members 1, 1'. It is composed of three inverted U-shaped roll bars 7, 8, and 9 that are connected, and the front roll bar 7, the frontmost cross member 2, and the left and right support plates 1a and 1a' are reinforced in a cross shape. The center roll bar 8 and the rear roll bar 9 are connected via a reinforcing member 11 at their tops. A sliding column supporting a steering handle 13 is attached to the center of the front roll bar 7.

A fuel tank 12 is disposed between the pair of reinforcing members 6, 6' along the center line between both longitudinal members 1, 1',
This fuel tank 12 consists of a cross member 3 and both reinforcing members 6, 6'.
bolted to.

A floor plate 16 is placed on the lower surface of the vehicle body frame F.
Also, on the top surface is the front seat 1 for the operator D.
4 and a rear seat 15 for passenger A are installed, and in this case, these backrests 14a, 15a
are arranged substantially along the center roll bar 8 and the rear roll bar 9, respectively. Of course, the heights of these roll bars 8 and 9 are selected in advance so that they pass over the heads of the operator D and the passenger A, respectively.

In FIGS. 4 to 6, the power unit P consists of an engine E and a pair of left and right belt-type automatic transmissions M and M' disposed on both sides of the rear thereof.
Each transmission M, M' is equipped with a reduction gear mechanism R on the output side.

The engine E is arranged with its crankshaft 20 facing in the left-right direction of the vehicle, and has an output shaft 21 on one side of the crankshaft 20, and a primary inertia force balancing shaft 22 and a pump on the other side. A drive shaft 23 and a starting motor 24 are each arranged parallel to the crankshaft 20. A generator 25 is attached to one end of the crankshaft 20, and a centrifugal automatic start clutch 26 is attached to the other end, and a forward/reverse switching device 27 is provided between the clutch 26 and the output shaft 21.

This device 27 includes a drive gear 28 fixed to the output member of the clutch 26, a relay gear 29 rotatably supported by the output shaft 21 and constantly meshing with the drive gear 28, and an idle shaft 30 parallel to the crankshaft 20. A small-diameter idle gear 31 that is freely supported and always meshes with the drive gear 28, a large-diameter idle gear 32 that is integrally connected to the small-diameter idle gear 31, and an output adjacent to the relay gear 29 and the large-diameter idle gear 32. It is composed of a switching gear 33 that is slidably spline-fitted onto the shaft 21. The switching gear 33 is movable along the output shaft 21 between a forward position on the right and a reverse position on the left in FIG. 5A, and is connected to the relay gear 29 in the forward position. A dog clutch consisting of a dog 34 and a dog hole 35 that can engage with each other is provided on the switching gear 33 and the relay gear 29, and in the reverse position, the dog clutches 34 and 35 are released and the switching gear 33 meshes with the large-diameter idle gear 32. I'm starting to do that.

Therefore, when the switching gear 33 is placed in the forward position, the rotational torque of the crankshaft 20 is transferred to the starting clutch 26,
The signal is transmitted to the output shaft 21 through the drive gear 28, the relay gear 29, and the switching gear 33 in order, and can be rotated in the normal direction. Furthermore, if the switching gear 33 is shifted to the reverse position, the rotational torque can be applied to the starting clutch 2.
6, drive gear 28, relay gear 29, small diameter idle gear 31, large diameter idle gear 32, and switching gear 3
3 to the output shaft 21 in sequence, and can be reversed.

An annular engagement groove 3 is provided on the outer periphery of the boss portion of the switching gear 33.
A shift fork 38, which is slidably supported on a guide shaft 37 parallel to the crankshaft 20, is engaged with the groove 33, and a projection 38a of the boss portion of the shift fork 38 is engaged with the groove 33. , is engaged with a cam groove 39a of a shift drum 39 disposed parallel to the guide shaft 37. The shift drum 39 has a shift lever 40 fixed to one end thereof.
When the shift fork 38 is rotated in one direction or the other direction by the guiding action of the cam groove 39a, the shift fork 38
to the right or left to switch the switching gear 33.
can be shifted to forward or reverse positions.

The primary inertial force balancing shaft 22 connects to the crankshaft 2 through a driving gear 41 and a driven gear 42 having the same diameter.
Rotates synchronously from 0. The weight 2 of this balancing shaft 22
2a is provided at a position where it enters between a pair of opposing crank webs 20a, 20a when approaching the crankshaft 20, but this weight 22a
Since the primary inertia force balancing effect of the engine E is well known, its explanation will be omitted.

The pump drive shaft 23 is driven by the crankshaft 20 via a chain transmission device 43. A lubricating oil pump 44 is attached to one end of the pump drive shaft 23.
Cooling water pumps 45 are connected to the other ends, and the water pumps 45 can be easily attached and detached as follows.

That is, a rotating shaft 47 having an impeller 46 of the water pump 45 is connected to the pump drive shaft 23 via a removable joint 48, and a pump housing 49 that supports the rotating shaft 47 and houses the impeller 46 is It is fixed to the crankcase 50 of the engine E with bolts 51. Therefore, bolt 51
By removing the water pump 45, the water pump 45 can be easily taken out by the engine E, which is convenient for maintenance. Incidentally, when the engine E is an air-cooled type, the water pump 45 is removed in this way, and an appropriate blind cover is provided on the opening of the crankcase 50 behind the pump housing 49.

As shown in FIGS. 5A and 5B, a signal protrusion 52 of an ignition pulser is protruded from the outer circumferential surface of the rotor 25a of the generator 25, and a pick-up coil 53 of the ignition pulser is guided along the turning path of the signal protrusion 52. so that they face each other with a certain gap between them,
The board 53a is fixed to a fixed support base 54 in the crankcase 50 with bolts 55. In order to facilitate position adjustment and attachment/detachment of the pick-up coil 53, a working window 56 is provided in the end wall of the crankcase 50 facing the pick-up coil 53, and this window 56 is normally closed by a cap 57.

The pair of belt-type automatic transmissions M and M' are connected to both ends of the output shaft 21 of the engine E and the left and right drive wheels Wf,
It is arranged so as to connect each space with Wf'. Therefore, both drive wheels Wf, Wf' are connected in parallel to the output shaft 21 via automatic transmissions M, M', respectively.

Since the belt type automatic transmissions M and M' have the same structure, only the structure of the left one M will be described. A variable diameter drive pulley 5 is attached to the end of the output shaft 21.
A variable driven pulley 59 is attached to the driven shaft 61 which is the input shaft of the reduction gear mechanism R, and an endless V-belt 6 is connected between the pulleys 58 and 59.
0 is suspended. The driving pulley 58 includes a centrifugal mechanism 62 that operates to increase its effective diameter as its rotational speed increases, while the driven pulley 59 includes a spring 63 that constantly operates to increase its effective diameter. , due to the interaction between the centrifugal mechanism 62 and the spring 63, the output shaft 21 and the driven shaft 61
The gear ratio between the two is automatically decreased as the rotational speed of the output shaft 21 increases.

A wheel drive shaft 65 is spline-coupled to the outer end of the output shaft 64 of the reduction gear mechanism R, and an axle 67 fixed to a hub 66 of the drive wheel Wf is connected to this wheel drive shaft 65 via a constant velocity joint 68. be done. Therefore, the power that has been changed in speed and transmitted to the driven shaft 61 is appropriately torque amplified by the reduction gear mechanism R, and then transmitted to the axle shaft 67 via the wheel drive shaft 65 and the constant velocity joint 68, and is then transmitted to the drive wheel Wf. to drive.

Since the left and right drive wheels Wf, Wf' are connected in parallel to the output shaft 21 via such automatic transmissions M, M', both drive wheels are
When a rotational speed difference occurs between Wf and Wf', a difference occurs in the gear ratios of both automatic transmissions M and M', and as a result, the output torque of the output shaft 21 is
It is distributed among them according to the rotational speed of Wf′. That is, the automatic transmissions M and M' each perform a normal speed change function, and can also work together to perform a differential function.

Casing 70 as a power unit case
The crankcase 50 accommodates and supports the crankshaft 20, output shaft 21, etc. of the engine E, and a pair of left and right transmission cases 71 whose front ends are integrally connected via the crankcase 50.
71', which is constructed as a rigid body as a whole, and a pair of left and right automatic transmissions M, M' are accommodated in the pair of left and right transmission cases 71, 71', respectively, and in particular, the transmissions M, M' drive pulley 5
8 is connected to the front end of the transmission case 71, 71' via a partition wall 72 and the output shaft 21 (described later), and a driven pulley 59 is connected to the transmission case 71, 71' via a partition wall 73 (described later) and the driven shaft 61.
are supported at the rear end of each. Both transmission cases 71 and 71' are arranged substantially horizontally so as to sandwich the front end portion of the vehicle body frame F from the left and right sides.
In this way, both transmission cases 71 and 7
The space between 1' can be effectively used as a vehicle body space, making the vehicle more compact and contributing to lowering the center of gravity of the power unit P.

Crank case 50 and each transmission case 7
1 and 71', there is a partition wall 72 that partitions them in an oil-tight manner, and inside each transmission case 71, 71' there are both pulleys 58, 59 of each automatic transmission M, M'.
A partition wall 73 is provided to oil-tightly partition the transmission mechanism including the transmission mechanism R and the reduction gear mechanism R, and the transmission mechanism of each automatic transmission uses a dry type, and the reduction gear mechanism R uses a wet type.

The casing 70 is divided into several blocks and cast as follows. That is, the central part of the crankcase 50, the central part and each transmission case 71,
71' and each transmission case 71,
71' is divided along a plane perpendicular to the axis of the crankshaft 20, and the thus divided blocks are designated as blocks 1 to 6 from the left in Fig. 5.
They are called 70 ₁ to 70 ₆ . These blocks ₇₀₁ to ₇₀₆ are bolted together between adjacent blocks.

Support brackets 74 to 77 are integrally provided on the outer surfaces of the second to _fifth blocks ₇₀₂ to 705, respectively, and
A power unit P is connected between these support brackets 74 to 77 and support caps 79 to 82 which are connected to these through bolts 78, respectively.
The crankshaft 2 is connected to the vehicle body frame F.
A single pivot 83 arranged parallel to 0 is clamped. At this time, the support surfaces of each of the support brackets 74 to 77 and the support caps 79 to 82 are each formed into a semicircular shape that is easy to process and can be brought into close contact with the circumferential surface of the pivot shaft 83. Each through bolt 78 is passed through the pivot 83 for proper fastening. In this way, the second to fifth blocks ₇₀₂ to ₇₀₅ are also connected to each other by the pivot 83, increasing the strength of the connection.

Furthermore, each set of support brackets and caps 7
4,79;75,80;76,81;77,82
The mating surfaces of are shifted in phase from each other in the circumferential direction of the pivot shaft 83. In this way, the support bracket 74
77 and the relatively weak portions of the plurality of through bolts 78 are not biased in one direction, and can firmly support the pivot shaft 83 in all directions.

The pivot 83 supports the support bracket 7 at both outer positions.
4, 77, are supported on the left and right support plates 1a, 1a' of the vehicle body frame F via a pair of left and right Neidhard type spring devices Sf, Sf', and the spring devices Sf, Sf' The suspension device of the present invention is interposed between the frame F and the casing 70 (power unit case). These spring devices Sf and Sf′ have the same structure, so the one on the left
To explain only Sf, this spring device Sf is
As shown in FIG. 7, there is a housing 90 having a spring chamber 91 whose basic shape is a hexagonal cross section;
and six cylindrical rubber springs 93 filled between the housing 90 and the spring actuating body 92 at the six corners of the spring chamber 91. Fixed by multi-face fitting or spline fitting. housing 90
A mounting flange 94 is integrally formed on the outer peripheral surface of the mounting flange 94, which protrudes over half the circumference thereof.

On the other hand, a semicircular support recess 95 opening toward the front is formed in the support plates 1a, 1a' of the vehicle body frame F, and the housing 90 is fitted into this recess 95 so that its mounting flange 94 is attached to the support plate 1a, 1
a' with a plurality of bolts 96.

Therefore, the power unit P drives the left and right drive wheels Wf,
When Wf' swings around the pivot shaft 83 as Wf' moves up and down, the spring actuating body 92 rotates relative to the housing 90 and applies compressive deformation to all the rubber springs 93 at the same time. Drive wheels Wf, Wf' are elastically suspended by the repulsive force of 93.
By the way, the casing 70 of the power unit P
constitutes a rigid body as described above, and both drive wheels Wf,
Since Wf' is connected, a stabilizer function is provided in which the vertical vibration of one drive wheel is suppressed by the other drive wheel.

In order to damp the vertical movement of both drive wheels Wf, Wf', a hydraulic damper 9 is installed between each of the support plates 1a, 1a' of the vehicle body frame F and the transmission cases 71, 71'.
7 is interposed.

The pivot shaft 83 is arranged to pass through the center of gravity of the power unit P. In this way, the drive wheel
Axis 8 consisting of Wf, Wf' and power unit P
The moment of inertia of the swing system around the drive wheels Wf, Wf' can be significantly reduced, and as a result, the road followability of the driving wheels Wf, Wf' is improved, and the load burden on the Neidhardt spring devices Sf, Sf' is reduced.

Furthermore, in order to reduce the moment of inertia, in the illustrated example, the balancing shaft 22, the starter motor 24, and the water pump 45, which are relatively heavy, are connected to the driving wheels.
It is placed at the front of the engine E so as to balance the weight of Wf and Wf'. In addition, the water pump 45 is connected to the engine E.
It is convenient to dispose it at the front of the vehicle body frame F, since its maintenance can be performed without being obstructed by the vehicle body frame F.

On the outer surface of each mission case 71, 71',
A support tube 100 surrounding the wheel drive shaft 65 is integrally formed, and an outer tube 101 rotatably supported by the support tube 100 rotatably supports the hub 66 of the corresponding drive wheel Wf, Wf'. Natsukuru 102 is
The constant velocity joint 68 is connected via a pair of king pins 103 that are coaxially arranged to sandwich the swing center of the constant velocity joint 68, and the knuckle 102 is connected to the steering handle 13 via a steering mechanism (not shown).
Therefore, by rotating the steering handle 13 to rotate the knuckle 102 around the king pin 103, the drive wheels Wf, Wf' can be turned.

Furthermore, the nutkuru 102 has a corresponding drive wheel.
A back plate 104 of the brake device B (drum type in the illustrated example) of Wf, Wf' is fixed, and in order to suppress the rotation of this back plate 104, a restraining arm 105 protruding from the outer surface of the outer cylinder 101 is attached to a torque rod. It is connected to the vehicle body frame F via 106. Therefore, when braking, the back plate 10
4 is supported by the vehicle body frame F via the nutcle 102, the outer cylinder 101, and the torque rod 106. In addition, when the power unit P swings around the pivot shaft 83, the nut 1 is
02, relative rotational displacement between the outer cylinder 101 and the support cylinder 100 in a connected relationship is allowed.

A rear fork 111 is pivotally attached to the rear end of the vehicle body frame F via a pivot shaft 110 so as to be able to swing vertically.
The driven wheel Wr is pivotally supported at the rear end of this. In order to suspend the rear fork 111, a spring device Sr having the same structure as the Neidhardt type spring device Sf is interposed between the pivot shaft 110 and the rear fork 111.
Further, a hydraulic damper 112 is interposed between the rear fork 111 and the vehicle body frame F to damp the vertical movement of the driven wheel Wr.

FIG. 8 shows a second embodiment of the present invention. To explain only the differences from the previous embodiment, input shafts 120, 120 to which drive pulleys 58 of left and right automatic transmissions M, M' are mounted ' is separated from the output shaft 21 of the engine E, and is disposed adjacent to and coaxially with both ends of the crankshaft 20, and between the input shafts 120 and 120' is a drive gear 121.
and a driven gear 122. The input shaft 12 of the casing 70 of the power unit P
The part surrounding 0,120' is a rectangular cylindrical pivot 18
3,183', these pivots 183,1
83' is supported on the vehicle body frame F via Neidhardt type spring devices Sf, Sf'. Thus, the center of swing of the power unit P is located at or near the center of the crankshaft 20. In this way, rotational vibrations caused by torque fluctuations of the engine E can be effectively absorbed by the Neidhardt spring devices Sf, Sf'. The rest of the structure is the same as that of the previous embodiment, so in FIG. 8, the same reference numerals are given to the parts corresponding to those of the previous embodiment.

C. Effects of the Invention As described above, according to the present invention, a pair of left and right belt type automatic transmissions are respectively interposed between the output shaft of the engine and a pair of left and right drive wheels, and the output shaft is connected to both drive wheels. In a power transmission device for a vehicle, the pair of left and right belt-type automatic transmissions are housed in a pair of left and right transmission cases, and a transmission is provided at one end of each transmission case. The drive pulley is supported at the other end, and the driven pulley of the transmission is supported at the other end, and one end of the pair of left and right transmission cases are integrally connected to each other via the crankcase of the engine to form a power unit case. The power unit case is pivotally supported on the vehicle body frame so as to be able to swing up and down, and a suspension device is interposed between the power unit and the vehicle body frame, and a suspension device is provided between the power unit case and the vehicle body frame, and a suspension device is provided between the power unit case and the vehicle body frame. Since each of the drive wheels connected to each driven pulley is rotatably supported,
Each transmission case of a pair of left and right belt-type automatic transmissions that can cooperate with each other to perform a differential function can also be used as a swing arm member for suspending a pair of left and right drive wheels, and The reinforcing coupling member that integrates the swing arm members to mutually reinforce each other can also serve as the engine crankcase, and the shaft support of the power unit case to the vehicle body can also be connected to the engine and transmission case to the vehicle body. As a result, both automatic transmissions can be provided with a differential function, and the structure of the power transmission device can be greatly simplified, making the device more compact. This can greatly contribute to economic development and cost reduction. In addition, by supporting the drive and driven pulleys of each automatic transmission on one end and the other end of a common transmission case, the distance between the drive and driven pulleys can be adjusted regardless of the vertical swing of the drive wheels. can be kept constant at all times, so the automatic gear shifting function is always performed accurately.

[Brief explanation of drawings]

1 to 7 show a first embodiment of the present invention, in which FIG. 1 is a perspective view of the vehicle body frame and power unit separated, and FIGS.
The figures are a plan view and a side view of the vehicle, FIG. 4 is a side view of the power unit, FIG. 5 is a longitudinal sectional plan view of the main parts of the power unit, and FIG. 5A is an enlarged longitudinal sectional plan view of the engine part of the power unit. , Figure 5B is the fifth
Figure A is a sectional view taken along the line VB-VB, Figure 6 is a side view of the power transmission system of the engine, and Figure 7 is a cross-sectional view of Figure 5.
FIG. 8 is an enlarged line sectional view and a longitudinal sectional plan view of a main part of a power unit showing a second embodiment of the present invention. E...engine, M, M'...belt type automatic transmission,
Sf, Sf'...Neidhardt spring device as a suspension system, Wf, Wf'...drive wheel, 21...output shaft, 58
... Drive pulley, 59 ... Driven pulley, 70 ... Casing as power unit case, 71, 7
1'...Mission case.

Claims (1)

[Claims] 1 Output shaft 21 of engine E and a pair of left and right drive wheels
A pair of left and right belt-type automatic transmissions M, M' are interposed between Wf, Wf', respectively, and both driving wheels Wf, Wf' are connected in parallel to the output shaft 21. In the transmission device, the pair of left and right belt type automatic transmissions M, M' are housed in a pair of left and right transmission cases 71, 71', respectively;
A driving pulley 58 of the transmissions M, M' is supported at one end of each transmission case 71, 71', and a driven pulley 59 of the transmission M, M' is supported at the other end. Shion case 7
1 and 71' are integrally connected to each other via the crank case 50 of the engine E to form a power unit case 70, and the power unit case 70 is pivotably supported on the vehicle body frame F so as to be able to swing vertically. At the same time, suspension devices Sf and Sf' are interposed between the power unit 70 and the vehicle body frame F, and are connected to the corresponding driven pulleys 59 at the other ends of the pair of left and right transmission cases 71 and 71', respectively. A power transmission device for a vehicle, characterized in that each of the driving wheels Wf, Wf' is rotatably supported.