JP4282849B2 - Small vehicle transmission - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present invention relates to an engine crankshaft.A multi-stage transmission housed in a crankcase that supports the crankshaft, the crankshaft projecting outward from the side wall of the crankcase, and theMulti-speed transmission input shaftBetween each outer end ofPump impeller andBit-Connected via fluid transmission means with bin impeller,smallThe present invention relates to a type vehicle transmission device.
[0002]
[Prior art]
  Such a small vehicle transmission device is already known as disclosed in, for example, Japanese Patent Laid-Open No. 57-69163.
[0003]
[Problems to be solved by the invention]
  In such a conventional small vehicle transmission device, as disclosed in the above-mentioned publication, the crankshaft of the engine and the input shaft of the multi-stage transmission are connected only via a torque converter, and at the time of starting or shifting. This torque shock is absorbed by the sliding action of the torque converter.
[0004]
  However, although torque converters and fluid couplings have a slip function, they transmit torque to some extent as long as power is input from the engine. Therefore, with conventional devices, when starting the transmission from the neutral position to the low position, Even when the engine is idling, a creep phenomenon occurs in which the power is transmitted to the driving wheels of the vehicle. Further, since friction caused by transmission torque always acts on the switching sliding portion of the transmission during traveling, there are disadvantages that the switching resistance of the transmission is large and a large shift operation load is required.
[0005]
  The present invention has been made in view of such circumstances, and provides a transmission for a small vehicle that eliminates the creep phenomenon and allows the speed change operation of the transmission to be performed lightly. Objective.
[0006]
[Means for Solving the Problems]
  In order to achieve the above object, the present invention provides an engine crankshaft.A multi-stage transmission housed in a crankcase that supports the crankshaft, the crankshaft projecting outward from the side wall of the crankcase, and theMulti-speed transmission input shaftBetween each outer end ofPump impeller andBit-In a small vehicle transmission device connected via fluid transmission means with a bin impeller,The pump impeller and the turbine impeller of the fluid transmission means are rotatably supported on the outer end portion of the crankshaft, and on the opposite side of the crankcase of the fluid transmission means.The crankshaft and theConnect between pump impellersShift clutchA primary reduction gear is mounted on the crankshaft, and connects between the turbine casing and the input shaft between the crankcase and the turbine impeller.This is the first feature.
[0007]
  The fluid transmission means corresponds to the torque converter T in the embodiment of the present invention.
[0008]
  According to the first feature, when the engine is idling, even if the transmission is in the low position, the transmission clutch is controlled to be in the OFF state, thereby interrupting the transmission of power to and after the transmission clutch regardless of the presence of the fluid transmission means. Thus, the creep phenomenon can be prevented. Also, during gear shifting operation, the existence of fluid transmission means is first controlled by controlling the gear shifting clutch to the off state.InRegardless of this, the transmission can be in a no-load state, and the gear change can be easily performed without a torque shock.
[0009]
  Moreover, among the primary reduction gear, the fluid transmission means, and the speed change clutch, the primary reduction gear is disposed closest to the side wall of the crankcase, and then the fluid transmission means is disposed next, so that the operation of the primary reduction gear is performed. As a result, the bending moment applied to the crankshaft and the input shaft can be minimized, and the fluid transmission means is heavier than the speed change clutch, but the weight can also minimize the bending moment applied to the crankshaft. In combination with the downsizing of the fluid transmission means and the speed change clutch, it is possible to improve the durability of the crankshaft, the input shaft, and the bearings that support them.
[0010]
  Further, in addition to the first feature, the present invention has a second feature that the shift clutch is configured to be an on / off type having no half-clutch region.
[0011]
  According to the second feature, it is possible to improve the durability of the transmission clutch by avoiding heat generation and wear of the friction portion due to the half clutch. Moreover, even if the speed change clutch jumps from the off state to the half clutch region and immediately shifts to the on state, the torque shock associated therewith is absorbed by the sliding action of the fluid transmission means, so that the riding comfort is not hindered. .
[0012]
  Furthermore, the present invention provides, in addition to the second feature, a shift clutch actuator that operates to turn off the shift clutch, an idling sensor that detects an idling state of the engine, and a shift operation of the multi-stage transmission. A third feature is that the shift sensor is configured to operate when each output signal of the shift sensor is generated.
[0013]
  According to the third feature, the on / off operation of the speed change clutch can be accurately performed at the time of start and at the time of a speed change operation, which can contribute to an improvement in durability of the clutch.
[0014]
  In addition to the first feature, the present invention further includes a plurality of drive friction plates connected to the input side, and a plurality of driven friction plates stacked alternately with these drive friction plates and connected to the output side. A frictional engagement means, a centrifugal mechanism for turning on the multi-plate frictional engagement means in response to an increase in rotational speed on the input side over a predetermined value, and the shifting of the multi-stage transmission even during operation of the centrifugal mechanism. A fourth feature of the present invention is that the shift clutch is sometimes configured with a clutch-off mechanism that turns off the multi-plate friction engagement means.
[0015]
  The multi-plate friction engagement means corresponds to a clutch outer 137, a clutch inner 138, a driving friction plate 139, a driven friction plate 140, and a pressure receiving ring 141 in a fourth embodiment to be described later of the present invention. Corresponding to the drive plate 135, the centrifugal weight 143, and the pivot 144, and the clutch-off mechanism corresponds to the release cam 150, the fixed cam 152, and the clutch arm 153.
[0016]
  According to the fourth feature, when the engine is idling, the multi-plate friction engagement means is turned off by the centrifugal mechanism, so that the vehicle can be prevented from moving at a slow speed due to the creep phenomenon of the fluid transmission means. At the time of shifting, the clutch-off mechanism can be operated to turn off the multi-plate friction engagement means to reliably eliminate the shift shock.
[0017]
  Furthermore, the present invention is characterized in that, in addition to any of the first to fourth features, the torque capacity of the transmission clutch is set to be equal to or greater than the torque capacity of the fluid transmission means.
[0018]
  According to the fifth feature, it is possible to prevent the shift clutch from slipping and to ensure its durability even under full load conditions.
[0019]
  In addition to the first feature of the present invention, an oil chamber to which lubricating oil from an oil pump is supplied is formed on the outer periphery of the crankshaft, and lubricating oil is supplied from the oil chamber to the transmission clutch. A sixth feature is that a first oil passage and a second oil passage for supplying lubricating oil to the fluid transmission means are branched.
[0020]
  The first oil passage corresponds to a through hole 169 in a fourth embodiment (to be described later) of the present invention, and the second oil passage includes an outflow hole 170 formed in the crankshaft, an upstream supply oil passage. 27a downstream side of 27a ₂ , Corresponding to the flow path constituted by the inflow holes 175.
[0021]
  In addition to the sixth feature of the present invention, the oil chamber is formed in a support cylinder provided in the transmission clutch so as to surround the crankshaft, and the first oil passage is formed in the first oil passage. A seventh feature is that the second cylinder is formed by a through hole drilled in the support cylinder, and the second oil passage is formed by a channel drilled in the crankshaft.
[0022]
  In addition to the seventh feature of the present invention, the oil chamber is defined by the crankshaft, the support cylinder, and a lid that closes an open surface of the support cylinder. The sixth feature is that the crankshaft communicates with a supply oil passage that is connected to the discharge port of the oil pump.
[0023]
  The supply oil passage is provided on the upstream side 27a of the upstream supply oil passage 27a in a fourth embodiment to be described later. ₁ Corresponding to
[0024]
DETAILED DESCRIPTION OF THE INVENTION
  DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below based on examples of the present invention shown in the accompanying drawings.
[0025]
  1 to 12 show a first embodiment of the present invention. FIG. 1 is a side view of a motorcycle to which the present invention is applied. FIG. 2 is a longitudinal sectional view of a power unit mounted on the motorcycle. Is an enlarged longitudinal sectional view of the transmission device in the power unit, FIG. 4 is a sectional view taken along line 4-4 in FIG. 3, FIG. 5 is a view taken along arrow 5-5 in FIG. Is an enlarged view showing the outlet valve of the speed change clutch in FIG. 3 in the closed state, FIG. 8 is an enlarged view showing the outlet valve in the opened state, FIG. 9 is a sectional view taken along line 9-9 in FIG. FIG. 11 is an enlarged view showing the control valve of the lockup clutch in FIG. 3 in a closed state, and FIG. 12 is an enlarged view showing the control valve in an opened state. FIG. 13 is a sectional view corresponding to FIG. 3, showing a second embodiment of the present invention, and FIG. 14 is a sectional view corresponding to FIG. 3, showing a third embodiment of the present invention. FIGS. 15 to 17 show a fourth embodiment of the present invention. FIG. 15 is a side view of a four-wheel buggy to which the present invention is applied. FIG. 16 is a longitudinal view of a power unit portion of the four-wheel buggy. FIG. 17 is an enlarged longitudinal sectional view of the power unit transmission device.
[0026]
  First, the description starts with the description of the first embodiment of the present invention shown in FIGS.
[0027]
  In FIG. 1, the motorcycle Vm has a saddle Sm attached to the upper part of the body frame Fm that supports the front wheel Wf and the rear wheel Wr, and a power unit P attached to the lower part thereof. A fuel tank Tfm is provided directly below the saddle Sm. Arranged.
[0028]
  As shown in FIGS. 1 and 2, the power unit P is configured by integrating an engine E and a multi-stage transmission M. The engine E is slidably fitted to a crankshaft 2 supported by a crankcase 1 via a pair of left and right ball bearings 3 and 3 'and a cylinder bore 5a of a cylinder block 5 as usual. A piston 7 connected to the crankshaft 2 via a connecting rod 6 is provided, and the crankshaft 2 is arranged in the left-right direction of the motorcycle Vm. Further, a cylinder head 4 defining a combustion chamber 4a is joined to the cylinder block 5 between the piston 7 and the top surface of the piston 7. The cylinder head 4 is connected to the suction and exhaust ports that open and close the exhaust port. An exhaust valve (not shown) and a camshaft 9 for opening and closing them are provided. The cam shaft 9 is rotatably supported by the cylinder head 4 in parallel with the crank shaft 2.
[0029]
  A transmission case 8 is integrally connected to the crankcase 1, and an input shaft 10 and an output shaft 11 of the multi-stage transmission M arranged in parallel to the crankshaft 2 are respectively provided by the left and right side walls of the transmission case 8. The bearings are supported by ball bearings 12, 12 '; 13, 13', and span the input shaft 10 and the output shaft 11 from the left side in FIG. 2 to the first speed gear train G1, the second speed gear train G2, and the third speed gear. A train G3 and a fourth speed gear train G4 are provided. When the driven gear G2b of the second speed gear train G2 and the drive gear G3a of the third speed gear train G3 also serve as shift gears, and both the shift gears G2b and G3a are both in the neutral position, the transmission M is in the neutral state. When the shift gear G2b moves left or right in the figure, the first speed gear train G1 or the third speed gear train G3 is established, and when the shift gear G3a moves left or right, the second speed gear train G2 or fourth gear A speed gear train G4 is established. The shift gears G2b and G3a are operated by a known pedal type or other manual type change device (not shown).
[0030]
  The right end of the crankshaft 2 and the right end of the input shaft 10 of the transmission M are connected to each other outside the crankcase 1 and the transmission case 8 through a transmission clutch Cc, a torque converter T, and a primary reduction gear 14 connected in series. Connected to each other. At that time, in particular, the transmission clutch Cc, the torque converter T, and the drive gear 14a of the primary speed reducer 14 are placed on the crankshaft 2 from the right side wall side of the crankcase 1 to the outer side. The shift clutch Cc is attached in this order. A right side cover 15 a covering these is joined to the right end surfaces of the crankcase 1 and the transmission case 8.
[0031]
  A rotor 17 of the generator 16 is fixed to the left end of the crankshaft 2, and a stator 18 thereof is attached to a left side cover 15 b that covers the generator 16 and is joined to the left end surface of the crankcase 1. The crankcase 1 and the cylinder block 5 are formed with a series of timing transmission chambers 90 on the left side wall opposite to the torque converter T and the primary speed reducer 14, and the crankshaft 2 rotates in the chamber 90. A timing transmission device 91 is housed that decelerates the signal to the camshaft 9 and transmits it to the camshaft 9. Thus, the primary speed reducer 14, the torque converter T, the speed change clutch Cc, the timing transmission 91 and the generator 16 are disposed inside the crankcase 1, that is, at both ends of the crankshaft 2 with the crank chamber interposed therebetween.
[0032]
  As shown in FIGS. 2 and 3, the crankshaft 2 is connected to the upstream supply oil passage 27 a that opens to the right end surface thereof and the downstream supply that communicates with the needle bearing 49 on the outer periphery of the crankpin that supports the large end of the connecting rod 6. The oil passage 27b, the orifice 48 that directly communicates both the oil passages 27a and 27b, the first inflow hole 43a extending in the radial direction from the upstream supply oil passage 27a toward the transmission clutch Cc, and the torque from the upstream supply oil passage 27a A second inflow hole 43b extending in the radial direction toward the converter T and an outflow hole 45 extending in the radial direction from the downstream supply oil passage 27b toward the torque converter T are provided. The oil pump 44 driven by the engine E pumps the oil sucked up from the oil reservoir 46 through the oil passage 27 formed in the right side cover 15a to the upstream supply oil passage 27a. The oil sump 46 is formed at the bottom of the crankcase 1, the transmission case 8, and the right side cover 15a.
[0033]
  Connected to the left end of the output shaft 11 of the transmission M is a chain-type final reduction device 19 that drives a rear wheel (not shown) of the motorcycle outside the transmission case 8.
[0034]
  2 and 3, the transmission clutch Cc has a cylindrical clutch casing 20 having an end wall 20 a at one end and a boss 20 b splined to the crankshaft 2 at the center, and the clutch casing 20 is provided in the clutch casing 20. A pressure plate 21 slidably fitted on the outer periphery of the boss 20b, a pressure receiving plate 22 oil-tightly fixed to the open end of the clutch casing 20, and between the pressure plate 21 and the pressure receiving plate 22. And a transmission plate 24 of a pump impeller 50 described later is spline-engaged with the inner periphery of the friction clutch plate 23 (see FIG. 4).
[0035]
  The pressure plate 21 defines a hydraulic chamber 25 between the end wall 20 a and the peripheral wall of the clutch casing 20. The hydraulic chamber 25 is connected to the first inflow hole 43a of the crankshaft 2 via an inlet valve 26 provided on the boss 20b of the clutch casing 20, and an outlet valve 28 provided on the outer peripheral portion of the end wall 20a. Through the clutch casing 20.
[0036]
  As shown in FIGS. 3 and 4, the boss 20 b has a plurality of (three in the illustrated example) valve holes 29 extending in parallel with the crankshaft 2, and the first inflow holes 43 a through the valve holes 29. A plurality of through holes 30 reaching the hydraulic chamber 25 are formed, and an inlet valve 26 formed of a spool valve is slidably fitted into each valve hole 29. When these inlet valves 26 occupy the right movement position in FIG. 3 (upper half side in FIG. 3), the through hole 30 is opened and when the left movement position occupies (see the lower half side in FIG. 3), The through hole 30 is closed. In addition, in order to ensure the communication between the through hole 30 of the boss 20b and the first inflow hole 43a of the crankshaft 2, some teeth of the spline portions that are fitted to each other of the crankshaft 2 and the boss 20b are cut off. Is effective.
[0037]
  Further, a plurality of (three in the illustrated example) outlet holes 32 are formed at equal intervals in the circumferential direction on the outer peripheral portion of the end wall 20a of the clutch casing 20, and these outlet holes 32 are opened and closed on the hydraulic chamber 25 side. One end of the outlet valve 28, which may be a reed valve, is caulked to the end wall 20a.
[0038]
  Further, a guide collar 33 communicating with each outlet hole 32 is fixed to the end wall 20a, and the valve opening rod 31 is slidably fitted to each guide collar 33. The valve-opening rod 31 has a groove 31a extending in the axial direction on the outer periphery thereof. When the valve-opening rod 31 occupies the right movement position in FIG. 3 (see the upper half of FIG. 3 and FIG. 7), When the outlet hole 32 is closed by the elastic force and occupies the left movement position (see the lower half side of FIG. 3 and FIG. 8), the outlet valve 28 is bent inwardly of the hydraulic chamber 25, thereby opening the outlet hole 32. It is designed to be opened.
[0039]
  A common valve operating plate 34 is connected to the outer ends of the inlet valve 26 and the valve opening rod 31. The valve actuating plate 34 is supported on the boss 20b of the clutch casing 20 so as to be slidable in the left-right direction in FIG. 3, and a stopper ring 35 for defining the right movement position is locked to the boss 20b. A return spring 36 that urges the valve operating plate 34 toward 35 is contracted between the clutch casing 20 and the valve operating plate 34.
[0040]
  A pressure ring 38 is mounted on the valve operating plate 34 via a release bearing 37 that concentrically surrounds the boss 20b, and an arm 39a fixed to the transmission clutch operating shaft 39 is engaged with the outer end surface of the pressure ring 38. In addition, by reciprocatingly rotating the speed change clutch operating shaft 39, the valve operating plate 34 can be moved left and right together with the inlet valve 26 and the valve opening rod 31 in cooperation with the return spring 36.
[0041]
  As shown in FIG. 6, the transmission clutch operating shaft 39 is connected to an electric or electromagnetic transmission clutch actuator 40 for rotating the transmission clutch operating shaft 39, and this transmission clutch actuator 40 detects the idling state of the engine E. The output signals of the idling sensor 41 and the shift sensor 42 for detecting the shift operation of the transmission M are input, and in response to any of these signals, the valve operating plate 34 shifts in the direction to move leftward in FIG. The clutch operation shaft 39 is rotated.
[0042]
  Here, the operation of the speed change clutch Cc will be described. When the engine E is operating and the idling sensor 41 and the speed change sensor 42 are not generating output signals, the speed change clutch actuator 40 remains in an inoperative state. The actuating plate 34 is held in the retracted position by the urging force of the return spring 36, that is, the rightward moving position in FIG. 3, and the inlet valve 26 is opened as shown in the upper half side of FIG. The outlet valve 28 is allowed to close. Therefore, the oil pumped from the oil pump 44 is supplied from the upstream supply oil passage 27 a to the hydraulic chamber 25 in the clutch casing 20 through the first inflow hole 43 a and the through hole 30 to fill the chamber 25.
[0043]
  Since the clutch casing 20 rotates together with the crankshaft 2, the oil in the hydraulic chamber 25 of the clutch casing 20 receives centrifugal force to generate hydraulic pressure, and the pressure plate 21 turns the friction clutch plate 23 to the pressure receiving plate 22 with the hydraulic pressure. By pressing against each other, the pressure plate 21, the pressure receiving plate 22, and the friction clutch plate 23 are frictionally engaged. That is, the transmission clutch Cc is turned on, and the output torque of the crankshaft 2 is transmitted from the friction clutch plate 23 to the torque converter T.
[0044]
  On the other hand, when the engine E is idling or when the transmission M is shifting, the idling sensor 41 or the shifting sensor 42 outputs an output signal, so that the shifting clutch actuator 40 that receives the output signal immediately operates and the shifting clutch operating shaft 39 is operated. And the valve operating plate 34 is moved to the left movement position in FIG. This closes the inlet valve 26 and opens the outlet valve 28 as shown in the lower half of FIG. As a result, the oil supply from the upstream supply oil passage 27a to the hydraulic chamber 25 is shut off, and the oil in the hydraulic chamber 25 is discharged out of the clutch casing 20 through the outlet hole 32 and the groove 31a of the valve opening rod 31. Since the hydraulic pressure in the hydraulic chamber 25 is lowered and the pressing force of the pressure plate 21 against the friction clutch plate 23 is drastically reduced, the friction engagement between the pressure plate 21, the pressure receiving plate 22, and the friction clutch plate 23 is released. That is, the transmission clutch Cc is turned off, and the torque transmission from the crankshaft 2 to the torque converter T is interrupted. The oil discharged out of the clutch casing 20 returns to the oil sump 46.
[0045]
  From this state, when the rotation of the engine E is accelerated for starting or the shifting operation is completed, when both the idling sensor 41 and the shifting sensor 42 stop the output signal, the shifting clutch actuator 40 is immediately inactivated. Returning, the valve operating plate 34 retreats to the right movement position by the urging force of the return spring 36 and opens the inlet valve 26 and closes the outlet valve 28 again. As is apparent from the above-described operation. The transmission clutch Cc returns from the off state to the on state without passing through the half clutch state. That is, the transmission clutch Cc is an on / off type that does not have a half-clutch region, and its torque capacity is set larger than that of the torque converter T.
[0046]
  In FIG. 3 again, the torque converter T includes a pump impeller 50, a turbine impeller 51, and a stator impeller 52. The pump impeller 50 is disposed adjacent to the pressure receiving plate 22, The boss 50 a is supported on the crankshaft 2 via the needle bearing 53. A transmission plate 24 that is spline-engaged with the inner periphery of the friction clutch plate 23 is fixed to the outer surface of the pump impeller 50. Therefore, the transmission torque of the friction clutch plate 23 is transmitted to the pump impeller 50 through the transmission plate 24.
[0047]
  The crankshaft 2 is supported by a needle bearing 54 on the right end of a stator shaft 60 disposed between the boss 50a of the pump impeller 50 and the ball bearing 3 'that supports the crankshaft 2. A boss 52a of the stator impeller 52 is connected to the stator shaft 60 by concavo-convex engagement. A stator arm plate 56 is fixed to the left end portion of the stator shaft 60, and an outer peripheral surface of a cylindrical portion 56 a that the stator arm plate 56 has at an intermediate portion is supported on the crankcase 1 via a ball bearing 57. The outer peripheral portion of the stator arm plate 56 is supported by the crankcase 1 via a free wheel 58.
[0048]
  A turbine impeller 51 opposed to the pump impeller 50 integrally has a turbine shaft 59 at the center, and a right end thereof is supported by a stator shaft 60 via a needle bearing 61, and a left end thereof is a stator arm plate 56. It is supported on the inner peripheral surface of the cylindrical portion 56a via a ball bearing 62. A one-way clutch 64 is provided between the turbine shaft 59 and the crankshaft 2 through the lateral hole 63 of the stator shaft 60. The one-way clutch 64 is turned on when a reverse load is applied to the turbine shaft 59 and directly connects the turbine shaft 59 and the crankshaft 2.
[0049]
  As shown in FIG. 3, the gaps between the boss 50 a of the pump impeller 50, the turbine shaft 59 and the boss 52 a of the stator impeller 52 serve as a fluid inlet 47 i of the torque converter T, and the turbine impeller of the turbine shaft 59. 51, a fluid outlet 47o of the torque converter T is provided in a portion extending outward, the fluid inlet 47i communicates with the second inflow hole 43b of the crankshaft 2, and the fluid outlet 47o passes through the lateral hole 63 of the stator shaft 60. And communicates with the outflow hole 45 of the crankshaft 2. Therefore, when the oil supplied from the oil pump 44 to the upstream supply oil passage 27a of the crankshaft 2 enters the second inflow hole 43b, the oil enters the oil chamber between the pump impeller 50 and the turbine impeller 51 through the fluid inlet 47i. After filling the oil chamber and a hydraulic chamber 77 of the lockup clutch Lc described later, the fluid flows from the fluid outlet 47o to the downstream supply oil passage 27b of the crankshaft 2 through the outflow hole 45.
[0050]
  The turbine shaft 59 is integrally formed with a drive gear 14 a of the primary reduction gear 14, and a driven gear 14 b that meshes with the drive gear 14 a is spline-coupled to the input shaft 10 of the transmission M. The primary reduction gear 14 configured in this way is disposed between the crankcase 1 and the torque converter T.
[0051]
  The operation of the torque converter T will be described.
[0052]
  When the output torque of the crankshaft 2 is transmitted to the pump impeller 50 via the ON transmission gear clutch Cc, the torque is fluidly transmitted to the turbine impeller 51 by the action of oil filling the torque converter T. Is done. At this time, if a torque amplifying action is generated between the two impellers 50 and 51, the reaction force accompanying this is borne by the stator impeller 52, and the stator impeller 52 is moved to the crankcase 1 by the locking action of the freewheel 58. Is fixedly supported. If the torque amplifying action is not generated, the stator impeller 52 can be idled by the idling action of the free wheel 58. Therefore, the pump impeller 50, the turbine impeller 51, and the stator impeller 52 are Both rotate in the same direction.
[0053]
  The torque transmitted from the pump impeller 50 to the turbine impeller 51 is transmitted to the input shaft 10 of the transmission M through the primary reduction gear 14 and the transmission gear trains G1 to G4, which are selected to be established, are output shaft 11 Then, it is sequentially transmitted to the rear wheel (not shown) through the final reduction gear 19 to drive it.
[0054]
  During engine braking during traveling, reverse load torque is applied to the turbine shaft 59 and the one-way clutch 64 is turned on. Therefore, the turbine shaft 59 and the crankshaft 2 are directly connected to each other, and the reverse load torque is applied to the torque converter T. It is transmitted to the crankshaft 2 without going through, and a good engine braking effect can be obtained.
[0055]
  In FIG. 3 again, between the pump impeller 50 and the turbine impeller 51, a lock-up clutch Lc that can bring them into a direct connection state is provided. The lock-up clutch Lc includes a cylindrical pump extension 70 connected to the outer periphery of the pump impeller 50 and surrounding the turbine impeller 51, and a support cylinder rotatably supported on the outer peripheral surface of the turbine shaft 59. A pressure plate 72 slidably fitted to 71 and oil-tightly fixed to the end of the pump extension 70 facing the pressure plate 72 and spline-fitted to the support cylinder 71. A pressure receiving plate 73 and an annular friction clutch plate 74 interposed between the pressure plate 72 and the pressure receiving plate 73 are provided. The friction clutch plate 74 is fixed to the outer surface of the turbine impeller 51. The outer peripheral portion is spline-engaged (see FIG. 9). The pressure plate 72 is defined by a stopper ring 76 that is engaged with the support cylinder 71 at a retracted position with respect to the pressure receiving plate 73.
[0056]
  The interior of the pump extension 70 is defined in a hydraulic chamber 77 by a pressure receiving plate 73. The hydraulic chamber 77 communicates with the interior of the pump impeller 50 and the turbine impeller 51 through opposed gaps. When the torque converter T is activated, the pressure becomes high as in the interior thereof.
[0057]
  As shown in FIGS. 3, 11, and 12, a plurality of (three in the illustrated example) valve holes are provided on the pressure plate 72 and the pressure receiving plate 73 at equal intervals in the circumferential direction on the inner peripheral side of the friction clutch plate 74. 78 and 79 are respectively drilled, and one end of a control valve 80 formed of a reed valve that can open and close the valve hole 78 of the pressurizing plate 72 on the hydraulic chamber 77 side is caulked and coupled to the pressurizing plate 72.
[0058]
  The valve holes 78 and 79 of the pressurizing plate 72 and the pressure receiving plate 73 are arranged coaxially with each other, and a control rod 81 for controlling the opening and closing of the control valve 80 is slidably fitted thereto. The control rod 81 has a communication groove 81a extending in the axial direction on the outer periphery thereof. When the control rod 81 occupies the left movement position in FIG. 3 (see the upper half side of FIG. 3 and FIG. 11), the control rod 80 The valve hole 78 is allowed to be closed by the elastic force of the control rod 81, and the communication groove 81a of the control rod 81 opens the inner peripheral side of the friction clutch plate 74 to the outside of the valve hole 79 of the pressure receiving plate 73, and occupies the right movement position. (Refer to the lower half of FIG. 3 and FIG. 12) The valve rod 79 of the pressure receiving plate 73 is closed by the control rod 81, and the control valve 80 is bent inward of the hydraulic chamber 77. On the inner peripheral side, both side surfaces of the pressure plate 72 are communicated with each other via a communication groove 81 a of the control rod 81.
[0059]
  A valve operating plate 82 is connected to the outer end of the control rod 81. The valve actuating plate 82 is supported by the support cylinder 71 so as to be slidable in the left-right direction in FIG. 3, and a stopper ring 83 that defines the leftward movement position is locked to the support cylinder 71. A return spring 84 that biases the valve operating plate 82 toward the end is contracted between the pressure receiving plate 73 and the valve operating plate 82.
[0060]
  An arm 86a of a lockup clutch operation shaft 86 (operation means) is engaged with the valve operating plate 82 via a release bearing 85 concentrically arranged with the support cylinder 71, and the lockup clutch operation shaft 86 is reciprocally rotated. Thus, in cooperation with the return spring 84, the valve operating plate 82 can be moved left and right together with the control rod 81.
[0061]
  As shown in FIG. 6, the lock-up clutch operating shaft 86 is connected to an electric or electromagnetic lock-up clutch actuator 87 for rotating the lock-up clutch operating shaft 86. The lock-up clutch actuator 87 has a predetermined value or less. An output signal of a vehicle speed sensor 88 for detecting the vehicle speed is input, and in response to the signal, the lockup clutch operating shaft 86 is rotated in a direction in which the valve operating plate 82 is moved to the right in FIG.
[0062]
  The operation of the lockup clutch Lc will be described. When the vehicle speed sensor 88 detects a vehicle speed less than a predetermined value and issues an output signal, the lockup clutch actuator 87 is actuated in response thereto, and the lockup clutch operating shaft 86 is rotated, and the valve operating plate 82 is shown in FIG. 3 to move to the right movement position. Accordingly, as shown in the lower half side of FIG. 3 and FIG. 12, the control rod 81 opens the control valve 80 and communicates both sides of the pressure plate 72 via the communication groove 81a. The hydraulic pressure of the hydraulic chamber 77 acts equally on the surface, and the pressure plate 72 is pressed to the retracted position by the pressing force of the control rod 81 against the control valve 80, whereby the pressure plate 72, the pressure receiving plate 73, and the friction clutch plate 74. The three friction engagements do not occur, and the lock-up clutch Lc is turned off. Accordingly, in this state, the pump impeller 50 and the turbine impeller 51 can be rotated relative to each other, and thus the torque can be amplified. Further, in this case, since the valve hole 79 of the pressure receiving plate 73 is closed by the control rod 81, unnecessary leakage of hydraulic pressure from the hydraulic chamber 77 to the valve hole 79 can be prevented.
[0063]
  When the vehicle speed rises above a predetermined value and the vehicle speed sensor 88 stops the output signal, the lockup clutch actuator 87 returns to the non-operating state, and the valve operating plate 82 is shown in the upper half side of FIG. 3 and FIG. In this manner, the return spring 84 is retracted to the left moving position by the urging force to allow the control valve 80 to close the valve hole 78 and the friction clutch plate 74 is provided with the communication groove 81a of the control rod 81 on the inner peripheral side thereof. Therefore, the pressurizing plate 72 receives the hydraulic pressure of the hydraulic chamber 77 only on its inner surface and presses the friction clutch plate 74 against the pressure receiving plate 73. As a result, the pressure plate 72, the pressure receiving plate 73, and the friction clutch plate 74 are frictionally engaged and the lockup clutch Lc is turned on, and the pump impeller 50 and the turbine impeller 51 are directly connected to each other. When the motorcycle Vm travels at a high speed, it is possible to eliminate slippage between the two impellers 50 and 51 and to increase transmission efficiency.
[0064]
  By the way, during operation of the engine E, oil discharged from the oil pump 44 first enters the upstream supply oil passage 27a, enters the hydraulic chamber 25 of the transmission clutch Cc via the first inflow hole 43a, and contributes to its operation and cooling. In addition, the oil flows into the oil chamber between the pump impeller 50 and the turbine impeller 51 and the hydraulic chamber 77 of the lockup clutch Lc via the second inflow hole 43b, and operates and cools the torque converter T and the lockup clutch Lc. Contribute. The oil that has flowed from the hydraulic chamber 77 through the outflow hole 45 to the downstream supply oil passage 27b is supplied to the needle bearing 49 on the outer periphery of the crankpin, contributes to the lubrication, and the oil that has finished the lubrication As it rotates, it scatters around and serves to lubricate the piston 7 and the like. The oil pump 44 originally supplies lubricating oil to the engine E, but the oil is used as working oil for the transmission clutch Cc, the torque converter T, and the lockup clutch Lc. Therefore, it is not necessary to provide a dedicated oil pump for supplying hydraulic oil, and the configuration can be simplified.
[0065]
  Further, since the upstream supply oil passage 27a and the downstream supply oil passage 27b provided in the crankshaft 2 are directly communicated with each other through the orifice 48, the oil sent from the oil pump 44 to the upstream supply oil passage 27a. A part of the oil flows directly to the downstream supply oil passage 27b through the orifice 48 without passing through the torque converter T or the like, so that the oil distribution ratio to the torque converter T and the engine E can be freely set by selecting the orifice 48. Can do.
[0066]
  On the other hand, in the torque converter T, even when the engine E is idling, torque is slightly transmitted between the pump impeller 50 and the turbine impeller 51. When idling, the transmission clutch Cc is controlled to be in the off state as described above. Therefore, even if the first speed gear train G1 of the multi-stage transmission M is established, the power transmission to and after the transmission clutch Cc can be interrupted and the creep phenomenon can be prevented regardless of the presence of the torque converter T. . This means that each transmission member of the multi-stage transmission M is placed in a no-load state. Therefore, in order to start the motorcycle Vm, the shift gear G2b is shifted leftward in FIG. Even when the gear train G1 is established, a smooth shift is possible without a torque shock. When the rotation of the engine E is accelerated to start, the speed change clutch Cc jumps over the half-clutch region and shifts to the on state at once. However, the torque shock associated therewith is caused by the pump impeller 50 and the turbine impeller of the torque converter T. 51 is absorbed by the mutual sliding action, and can help to amplify them smoothly so that the vehicle can start smoothly and contribute to the improvement of riding comfort.
[0067]
  Further, during the travel, the shift gears G2b and G3a are shifted in a desired direction to perform a desired shift, and each time the shift clutch Cc is controlled to be turned off as described above, each transmission of the multi-stage transmission M is transmitted. Since the member is in a no-load state, smooth shifting can be achieved without a torque shock. Even after the speed change, the speed change clutch Cc jumps over the half-clutch region and shifts to the on state at once. However, the torque shock associated therewith is also absorbed by the sliding action between the pump impeller 50 and the turbine impeller 51 of the torque converter T. The Therefore, the ride comfort is improved without causing the passenger to feel uncomfortable.
[0068]
  As described above, the torque converter T is made to absorb the torque shock generated when the transmission clutch Cc is turned on / off, so that the transmission clutch Cc can be configured as an on / off type having no half-clutch region. Therefore, heat generation and wear of the friction part due to the half-clutch can be avoided, and the durability of the transmission clutch Cc can be improved.
[0069]
  Further, since the torque capacity of the transmission clutch Cc is set to be greater than that of the torque converter T, it is possible to prevent the transmission clutch Cc from slipping and to ensure its durability even under full load conditions.
[0070]
  Since the crankshaft 2 rotates at a higher speed than the input shaft 10 of the multi-stage transmission M that is driven via the speed reducer 14, the torque converter T and the transmission clutch Cc attached to the crankshaft 2 bear the burden. The transmission torque is relatively small, and the capacity of the torque converter T and the speed change clutch Cc can be made smaller to make them more compact, and the power unit P can be made more compact by providing the torque converter T and the speed change clutch Cc. be able to.
[0071]
  MoreoverA pump impeller 50 and a turbine impeller 51 of the fluid transmission means T are rotatably supported on the outer end portion of the crankshaft 2, and the crankshaft 2 and the pump impeller 50 are opposite to the crankcase 1 of the fluid transmission means T. A shift clutch Cc that connects the two is connected to the crankshaft 2, and a primary reduction device 14 that connects the turbine impeller 51 and the input shaft 10 is disposed between the crankcase 1 and the turbine impeller 51. FromOf the primary speed reducer 14, torque converter T, and shift clutch Cc, the primary speed reducer 14 is disposed closest to the right side wall of the crankcase 1 and then the torque converter T is disposed next. The bending moment applied to the crankshaft 2 and the input shaft 10 along with the operation of the reduction gear 14 can be minimized, and the torque converter T is heavier than the speed change clutch Cc. The applied bending moment can also be minimized, and the durability of the crankshaft 2, the input shaft 10 and the bearings 3 'and 12' supporting them can be improved in combination with the compactness of the torque converter T and the transmission clutch Cc. You can plan.
[0072]
  On the crankshaft 2, the primary speed reducer 14, the torque converter T, the transmission clutch Cc, the timing transmission 91, and the generator 16 are arranged on opposite sides of the crank chamber. It is possible to equalize the right and left weight distribution, and even in the four-cycle engine E, the timing transmission 91 is interfered with the arrangement of the primary reduction gear 14 close to the right side wall of the crankcase 1. The durability of the crankshaft 2, the input shaft 10 and the bearings 3 'and 12' that support them can be ensured.
[0073]
  Further, the coaxial arrangement of the generator 16 and the torque converter T on the crankshaft 2 allows the rotational vibration generated by the generator 16 to be absorbed by the torque converter T, contributing to the quietness of the power unit P.
[0074]
  Next, a second embodiment of the present invention shown in FIG. 13 will be described.
[0075]
  This second embodiment differs from the previous two embodiments in that the lock-up clutch Lc ′ is configured as an automatic control type that depends on the rotational speed of the pump impeller 50. That is, the lock-up clutch Lc ′ is rotatably supported by the turbine shaft 59 and a cylindrical pump extension 70 that is connected to the outer periphery of the pump impeller 50 and surrounds the turbine impeller 51. A pressure receiving plate 93 that is oil-tightly coupled to the open end of the pump extension 70, a pressure plate 94 that is slidably supported by the turbine shaft 59 and disposed opposite to the inner surface of the pressure receiving plate 93, and these pressure plates 94 And an annular friction clutch plate 95 interposed between the pressure receiving plate 93 and a plate-shaped return that is interposed between the pump extension 70 and the pressure plate 94 to urge the pressure plate 94 in the opposite direction to the pressure receiving plate 93. The friction clutch plate 95 includes a spring 96, and an outer peripheral portion thereof is spline-engaged with a transmission plate 75 fixed to the outer surface of the turbine impeller 51. In addition, the pressure receiving plate 93 and the pressure plate 94 are formed with dogs 97 and recesses 98 that engage with each other so that they can slide relative to each other in the axial direction while rotating together.
[0076]
  The interior of the pump extension 70 is defined in a hydraulic chamber 99 by a pressure receiving plate 93. The hydraulic chamber 99 communicates with the interior of the pump impeller 50 and the turbine impeller 51 through opposing gaps, and is filled with oil. It is.
[0077]
  The pressure receiving plate 93 is provided with a relief hole 100 that opens the inner peripheral side of the friction clutch plate 95 to the outside of the pressure receiving plate 93 and an air vent groove 101 that extends in the axial direction on the inner peripheral surface of the pressure receiving plate 93.
[0078]
  Since the other configuration is the same as the configuration of the first embodiment, the same reference numerals are assigned to the portions corresponding to the first embodiment in the drawing, and the description thereof is omitted.
[0079]
  Thus, below the predetermined rotational speed of the pump impeller 50, since the centrifugal force of the oil filling the hydraulic chamber 99 in the pump extension 70 is small, the hydraulic pressure in the hydraulic chamber 99 does not increase, and the pressurizing plate 94 is returned to the return spring. Since the friction clutch plate 95 is released by returning to the reverse position by the urging force of 96, the lock-up clutch Lc 'is in the off state.
[0080]
  During this time, the oil in the hydraulic chamber 99 flows out from the relief hole 100 of the pressure receiving plate 93 to the outside, but since the amount thereof is extremely small, it does not hinder the subsequent pressure increase of the hydraulic chamber 99.
[0081]
  When the rotational speed of the pump impeller 50 exceeds a predetermined value, the centrifugal force of the oil in the hydraulic chamber 99 increases accordingly, and the hydraulic chamber 99 is boosted, so that the pressure plate 94 moves toward the pressure receiving plate 93 with the high hydraulic pressure. The friction clutch plate 95 is pinched between the pressure receiving plate 93 and the lockup clutch Lc ′ is turned on. Since the lock-up clutch Lc ′ in the on state is in a directly connected state between the pump impeller 50 and the turbine impeller 51, it is possible to eliminate slippage between the two impellers 50 and 51 and to increase transmission efficiency.
[0082]
  At that time, on the inner peripheral side of the friction clutch plate 95, oil does not escape because the oil flows out from the hole 100, so that a large pressure difference occurs between both surfaces of the pressure plate 94, and the pressure on the friction clutch plate 95 is reduced. Is done effectively.
[0083]
  Thus, by using the centrifugal hydraulic pressure of the hydraulic chamber 99 in the pump extension 70 connected to the pump impeller 50, it is possible to easily achieve automatic control of the lockup clutch Lc ′ to be dependent on the pump impeller rotational speed. it can.
[0084]
  Next, a third embodiment of the present invention shown in FIG. 14 will be described.
[0085]
  The third embodiment differs from the second embodiment in that the lockup clutch Lc ″ is configured as an automatic control type that depends on the rotational speed of the turbine impeller 52. This lockup clutch Lc ″ is different from the pump impeller. It is oil-tightly coupled to the 50 pump extensions 70 and disposed outside the torque converter side cover 105 that covers the turbine impeller 51. The torque converter side cover 105 is rotatably supported on the outer periphery of the turbine shaft 59, and the inside thereof communicates with an oil chamber between the pump impeller 50 and the turbine impeller 51, and the hydraulic oil is similar to the oil chamber. It is to be filled with.
[0086]
  The lock-up clutch Lc ″ is splined to the left end portion of the turbine shaft 59 and has a flat clutch cylinder 106 with an open end directed toward the torque converter side cover 105, and a seal member 113 in the cylinder hole 106 a of the clutch cylinder 106. And a pressurizing piston 107 defining a hydraulic chamber 108 between the end wall of the clutch cylinder 106 and an open end of the inner peripheral surface of the clutch cylinder 106. And a plurality of (two in the illustrated example) annular driven friction clutch plates 111 that are slidably engaged with the inner peripheral surface of the clutch cylinder 106 between the pressure receiving ring 109 and the pressure piston 107. , 111 and the driven friction clutch plates 111, 111, and a torque converter side cover An annular driving friction clutch plate 110 that engages an inner peripheral surface with a plurality of transmission claws 112 projecting outward from 105 in an axially slidable manner, and inner peripheral sides of these driving and driven friction clutch plates 110 and 111 The piston return spring 114 is disposed between the pressure piston 107 and the torque converter side cover 105 and urges the pressure piston 107 toward the hydraulic chamber 108. The clutch cylinder 106 and the pressure piston 107 are The dog 115 and the recess 116 are formed on the opposing surfaces so as to be able to slide relative to each other in the axial direction while rotating together.
[0087]
  The turbine shaft 59 is provided with a fluid outlet 47o and an inlet hole 117 for communicating the inside of the torque converter side cover 105 and the hydraulic chamber 108 of the clutch cylinder 106 with the inner peripheral side of the turbine shaft 59, respectively. The inside of the torque converter side cover 105 and the hydraulic chamber 108 of the clutch cylinder 106 are communicated with each other through the inlet hole 117 and the turbine shaft 59.
[0088]
  The circumferential wall of the clutch cylinder 106 is provided with a plurality of relief holes 118 that are arranged at equal intervals in the circumferential direction to open the hydraulic chamber 108 to the outside of the clutch cylinder 106, and on the inner circumferential surface of the clutch cylinder 106, An annular groove 119 that communicates between the escape holes 118 is provided, and a centrifugal valve 120 that closes the escape hole 118 with a centrifugal force at a predetermined rotational speed or more of the clutch cylinder 106 is disposed in the annular groove 119. The centrifugal valve 120 is composed of a free end ring made of a single elastic wire. At least one end 120a is engaged with one of the recesses 116 of the pressurizing piston 107, and the pressurizing piston 107, and hence the clutch. It rotates with the cylinder 106. The centrifugal valve 120 contracts in the radial direction so as to open the relief hole 118 in its free state. However, when the rotational speed of the clutch cylinder 106 exceeds a predetermined value, the centrifugal valve 120 expands in the radial direction due to centrifugal force and expands in an annular groove. It is in close contact with the bottom surface of 119 and closes all the escape holes 118.
[0089]
  Since the other configuration is the same as the configuration of the first embodiment, the same reference numerals are assigned to the portions corresponding to the first embodiment in the drawing, and the description thereof is omitted.
[0090]
  Thus, when the oil supplied from the oil pump 44 to the upstream supply oil passage 27a of the crankshaft 2 enters the second inflow hole 43b, the oil is introduced into the oil chamber between the pump impeller 50 and the turbine impeller 51 from the fluid inlet 47i. After entering and filling the oil chamber and the inside of the torque converter side cover 105, the fluid exits from the fluid outlet 47 o into the turbine shaft 59. The oil that has entered the turbine shaft 59 is divided into the inlet hole 117 and the outflow hole 45, and the oil that has moved to the inlet hole 117 flows into the hydraulic chamber 108 of the lockup clutch Lc ″ and the oil that has moved to the outflow hole 45. Flows to the downstream supply oil passage 27b of the crankshaft 2 in the same manner as in the previous embodiment.
[0091]
  By the way, the clutch cylinder 106 of the lock-up clutch Lc ″ is splined to the turbine shaft 59 and rotates together with the turbine shaft 59. Therefore, the centrifugal valve 120 resists centrifugal force when the turbine shaft 59 is below a predetermined rotational speed. The contracted state is maintained and the relief hole 118 is opened. Therefore, the oil flowing into the hydraulic chamber 108 from the inlet hole 117 flows out of the clutch cylinder 106 through the relief hole 118, so that the hydraulic pressure in the hydraulic chamber 108 does not increase. The pressure piston 107 is held in the retracted position by the urging force of the piston return spring 114, and the driving and driven friction clutch plates 110 and 111 are placed in the disengaged state, that is, the lock-up clutch Lc ″ is in the off state. It has become.
[0092]
  At this time, if foreign matter such as chips or wear powder exists in the hydraulic chamber 108, the foreign matter can be discharged out of the clutch cylinder 106 from the escape hole 118 together with the oil.
[0093]
  When the rotational speed of the turbine shaft 59 exceeds a predetermined value, the centrifugal valve 120 that rotates together with the turbine shaft 59 expands by its own increasing centrifugal force and closes all the escape holes 118. As a result, the hydraulic chamber 108 is filled with oil supplied from the inlet hole 117, and hydraulic pressure is generated in the hydraulic chamber 108 by the centrifugal force of the oil, and the pressurizing piston 107 moves toward the pressure receiving ring 109 with the hydraulic pressure. The drive and driven friction clutch plates 110 and 111 are frictionally engaged and the lock-up clutch Lc ″ is turned on. The lock-up clutch Lc ″ turned on is the pump impeller 50 and the turbine shaft. Since 59 is directly connected, slippage between the pump impeller 50 and the turbine impeller 51 can be eliminated, and transmission efficiency can be improved.
[0094]
  When the rotational speed of the turbine shaft 59 falls below a predetermined value, the centrifugal valve 120 is opened again, so that the residual pressure in the hydraulic chamber 108 can be released and quickly released from the hole 118, and therefore the lock-up clutch Lc " Off performance can be enhanced.
[0095]
  Thus, by using the centrifugal hydraulic pressure of the hydraulic chamber 108 in the clutch cylinder 106 connected to the turbine shaft 59, it is possible to easily achieve automatic control of the lockup clutch Lc ″ to be dependent on the rotational speed of the turbine impeller. .
[0096]
  Finally, a fourth embodiment of the present invention shown in FIGS. 15 to 17 will be described.
[0097]
  15 and 16, the four-wheel buggy Vb includes a fuel tank Tfb at the front and a saddle at the rear at the top of the body frame Fb that supports each pair of front wheels Wfa and Wfb and rear wheels Wra and Wrb. Sb is attached, and the power unit P is mounted below the Sb. The left and right front wheel drive shafts 121a and 121b connected to the left and right front wheels Wfa and Wfb are connected to each other via a differential 122, and the left and right rear wheels Wra and Wrb are directly connected by a single rear wheel drive shaft 123. Is done.
[0098]
  The power unit P is disposed with the crankshaft 2 of the engine E directed in the left-right direction of the four-wheel buggy Vb. A drive shaft 126 connected to the output shaft 11 of the transmission M via a bevel gear transmission 125 is disposed adjacent to the generator 16 side of the power unit P and directed in the front-rear direction. The front end of the drive shaft 126 is connected to the differential device 122 via an intermediate gear transmission 127, a front propeller shaft 128 and a bevel gear reduction device 129, and the rear end of the drive shaft 126 is a universal joint 130, a rear portion. The rear wheel drive shaft 123 is connected via a propeller shaft 131 and a bevel gear reduction device 132. Therefore, the front wheels Wfa and Wfb and the rear wheels Wra and Wrb can be driven by the power transmitted from the power unit P to the drive shaft 126.
[0099]
  As shown in FIG. 17, the power unit P of the fourth embodiment is different from the first embodiment in the configuration of the transmission clutch Cc ′ and the torque converter T ′.
[0100]
  The transmission clutch Cc ′ is connected to a drive plate 135 that is spline-fitted to the crankshaft 2 and fixed by a nut 134, and an outer surface of the drive plate 135.So as to surround the crankshaft 2And a bottomed cylindrical clutch outer 137 that is slidably supported by a support cylinder 136 that projects integrally therewith. The drive plate 135 is disposed adjacent to the end wall of the clutch outer 137 and its outer periphery is splined to the inner periphery of the clutch outer 137. A clutch inner 138 is coaxially disposed in the clutch outer 137, and a plurality of annular drive friction plates 139 slidably engaged with the inner periphery of the cylindrical portion of the clutch outer 137 and slidable on the outer periphery of the clutch inner 138. A plurality of annular driven friction plates 140 that are movably engaged with each other are alternately stacked. At this time, two driving friction plates 139, 139 are arranged outside the friction plates 139, 140, and the pressure receiving ring 141 facing the outer surface of the outer driving friction plate 139 is a cylinder of the clutch outer 137. Locked to the inner periphery of the part.
[0101]
  A separation spring 142 that urges the drive friction plates 139 and 139 on both sides in a separation direction is contracted. The inner driven friction plate 140 is opposed to a flange 138 a that protrudes from the outer periphery of the clutch inner 138.
[0102]
  A plurality of centrifugal weights 143 are swingably attached to the drive plate 135 by a pivot 144, and are arranged so that the pressing arm portion 143a of each centrifugal weight 143 can press the inner drive friction plate 139. . Further, the support cylinder 136 of the drive plate 135 is provided with a stopper 145 for defining a sliding limit of the clutch outer 137 outward (rightward in FIG. 17), and the clutch outer 137 is urged toward the stopper 145. A clutch spring 146 is mounted between the drive plate 135 and the clutch outer 137.
[0103]
  The clutch inner 138 is connected to an annular transmission member 148 via a known reverse load transmission screw mechanism 147, and this transmission member 148 is splined to the outer periphery of the boss 50a of the pump impeller 50 of the torque converter T '. .
[0104]
  Thus, when the engine E is idling, the rotational speed of the drive plate 135 that rotates together with the crankshaft 2 is low, and the centrifugal force of the weight portion of the centrifugal weight 143 is small, so that the pressing arm portion 143a is applied to the drive friction plate 139. The pressing force is also small. For this reason, the drive friction plates 139, 139 on both sides are separated by the urging force of the separation spring 142, the driven friction plate 140 is released, and the transmission clutch Cc 'is in the off state. Therefore, the transmission clutch Cc ′ in the off state cuts off the power transmission from the crankshaft 2 to the pump impeller 50 of the torque converter T ′, so that the four-wheeled vehicle by the creep action of the torque converter T ′ can be operated without operating the wheel brake. It is possible to prevent the buggy Vb from moving at a slow speed.
[0105]
  When the rotational speed of the engine E increases to a predetermined value or more, the centrifugal force of the weight portion of the centrifugal weight 143 increases accordingly, and the pressing arm portion 143a drives the driven and driven friction plates 139 and 140 to the pressure receiving ring 141. The transmission clutch Cc ′ is automatically turned on and the power of the crankshaft 2 is transmitted from the clutch inner 138 to the transmission member 148. To the pump impeller 50 of the torque converter T ′.
[0106]
  When the driving force of the centrifugal weight 143 and the pressing force on the driven friction plates 139 and 140 exceed the set load of the clutch spring 146, the clutch outer 137 is displaced leftward in FIG. 17 while bending the clutch spring 146. In addition, the centrifugal weight 143 is received by a stopper ring 157 provided in the clutch outer 137 so as to prevent further outward swinging, so that the drive and driven friction plates 139 and 140 The pressure contact force does not increase beyond the load of the clutch spring 146.
[0107]
  The clutch outer 137 has a boss 137a protruding on the outer surface thereof, and a release cam 150 is attached to the boss 137a via a release bearing 149. The release cam 150 is opposed to a fixed cam 152 attached to the right side cover 15 a via an adjustment bolt 151, and a ball 153 attached to the fixed cam 152 is engaged with a recess 150 a of the release cam 150.
[0108]
  In addition, the release cam 150 has an arm 154 having a notch 154a at its tip protruding in the radial direction, and the notch 154a has a tip of a clutch arm 156 fixed to a change spindle 155 used for switching operation of the transmission M. Are engaged.
[0109]
  Thus, when the change spindle 155 is rotated in order to switch the transmission M during the traveling of the four-wheel buggy Vb, the clutch arm 156 rotates the release cam 150 in the first half of the rotation. The release cam 150 pushes out the ball 153 of the fixed cam 152 from the recess 150a, and the reaction force at that time pushes the clutch outer 137 to the left in the drawing against the load of the clutch spring 146 through the release bearing 149. The pressure receiving ring 141 is separated from the group of driving and driven friction plates 139 and 140. On the other hand, the centrifugal weight 143 is prevented from swinging outward by the stopper ring 157 as described above, and the pressing arm portion 143a stops at the previous pressing position with respect to the driving and driven friction plates 139 and 140 groups. The drive and driven friction plates 139 and 140 are reliably separated from each other, and the transmission clutch Cc ′ is turned off.
[0110]
  The second half rotation of the change spindle 155 is used to switch the transmission M. After the switching, the release cam 150 is returned to the original position along with the return rotation of the change spindle 155, and the transmission clutch Cc ′ is moved to the clutch spring 146. And the sustained centrifugal force of the centrifugal weight 143 return to the on state.
[0111]
  In the torque converter T ′, the boss 50a of the pump impeller 50 splined to the transmission member 148 is supported on the crankshaft 2 via ball bearings 159, and the turbine shaft 59 connected to the turbine impeller 51 It is supported on the stator shaft 60 via a needle bearing 160 and a ball bearing 161. The boss 52a of the stator impeller 52 is supported on the crankshaft 2 via a ball bearing 162 or a needle bearing and is splined to the stator shaft 60.
[0112]
  A torque converter side cover 163 that covers the outside of the turbine impeller 51 is oil-tightly coupled to the pump extension 70 connected to the pump impeller 50, and the turbine shaft is interposed between the torque converter side cover 163 and the turbine shaft 59. A one-way clutch 64 that transmits only the reverse load torque from 59 to the torque converter side cover 163 is interposed. Therefore, when the reverse load torque applied to the drive shaft 126 is transmitted to the turbine shaft 59 through the transmission M and the primary reduction gear 14 during engine braking, the one-way clutch 64 is connected, and the reverse load torque is Torque is transmitted from the pump extension 70 to the pump impeller 50 and the transmission member 148.
[0113]
  When the reverse load torque is transmitted to the transmission member 148, in the speed change clutch Cc ′, the clutch inner 138 is pushed leftward in FIG. 17 by the operation of the screw mechanism 147, and the flange 138a is moved to the inner drive friction plate 139. And the drive and driven friction plates 139 and 140 are pressed against the pressure receiving ring 141, so that the transmission clutch Cc 'is turned on. Therefore, the reverse load torque is transmitted to the crankshaft 2 and a good engine braking effect is obtained.
[0114]
  The crankshaft 2 is provided with a partition wall 165 that partitions the upstream supply oil passage 27a and the downstream supply oil passage 27b, and the upstream supply oil passage 27a is further connected to the upstream side.27a ₁ And downstream27a ₂ A partition plug 166 that is divided into two parts is press-fitted.
[0115]
  In the transmission clutch Cc ′, the support cylinder 136 has an open surface closed by a lid 167 to define an oil chamber 168, and the oil chamber 168 is connected to the inner periphery of the clutch inner 138 through a through hole 169. Communicated to the side. Oil chamber 168Is an upstream side of the upstream supply oil passage 27a through an inflow hole 170 and an outflow hole 171 formed in the crankshaft 2.27a ₁ And downstream27a ₂ Communicated with
[0116]
  Further, in the torque converter T ′, a first small oil chamber 172 is provided on the right side of the boss 52a of the stator impeller 52, and a second small oil chamber 173 is provided on the left side. And communicates with the oil chamber between the turbine impeller 51 and the downstream side of the upstream supply oil passage 27a through an inflow hole 175 formed in the crankshaft 2.27a ₂ The second small oil chamber 173 communicates with an oil chamber between the turbine root wheel 51 and the stator impeller 52, and is connected to the downstream supply oil passage 27b through an outflow hole 176 formed in the crankshaft 2. Communicate.
[0117]
  Further, the first and second small oil chambers 172 and 173 communicate with each other through gaps between the bearings 162 that support the boss 52a and through holes 174 provided in the boss 52a.
[0118]
  Thus, the oil is supplied from the oil pump 44 driven by the engine E through the oil passage 27 to the upstream supply oil passage 27a.Upstream side 27a ₁ The oil enters the oil chamber 168 through the inflow hole 170, and then splits into the through hole 169 and the outflow hole 171. The oil that has passed through the through hole 169 passes through the friction portion and the sliding portion of the transmission clutch Cc '. Supplied to moving parts to contribute to cooling and lubrication.
[0119]
  On the other hand, the oil passing through the outflow hole 171 is downstream of the upstream supply oil passage 27a.27a ₂ The oil chamber between the pump impeller 50 and the turbine impeller 51 is filled from the inflow hole 175 through the first small oil chamber 172, and then to the downstream supply oil passage 27b through the second small oil chamber 173 and the outflow hole 176. It is used for lubrication of each part of the engine E.Thus, the upstream side 27a of the upstream supply oil passage 27a. ₁ Constitutes a supply oil passage to the oil chamber 168, and a through hole 169 constitutes a first oil passage for supplying lubricating oil from the oil chamber 168 to the transmission clutch Cc ', and the outflow hole 170 and the upstream supply oil passage. 27a downstream side of 27a ₂ And the inflow hole 175 constitute a second oil passage for supplying lubricating oil from the oil chamber 168 to the fluid transmission means T ′.
[0120]
  Incidentally, since the boss 52a of the stator impeller 52 is supported on the crankshaft 2 via the bearing 162, stable rotation is ensured. Moreover, since the bearing 162 faces both end surfaces of the first and second small oil chambers 172 and 173 on both sides of the boss 52a, it can be always kept in a good lubrication state. Further, since the first and second small oil chambers 172 and 173 communicate with each other via the bearing 162 and the through hole 174, when the amount of oil supplied from the oil pump 44 is small, the pump impeller 50 is When a large amount of oil is sucked into the interior by the rotation, the amount of oil supplied from the upstream oil supply passage 27a to the first small oil chamber 172 is insufficient, but the second small oil chamber 173 has a through hole so as to compensate for this. Since the oil flows to the first small oil chamber 172 through the bearing 174 and the bearing 162, generation of bubbles in the oil in the torque converter T ′ is suppressed, the reduction in transmission efficiency is prevented, and the bearing 162 is effectively lubricated. Can do.
[0121]
  The first and second oil chambers 172 and 173 can be communicated with each other via a through hole 174 ′ provided around the bearing 162, or both.
[0122]
  Further, the upstream supply oil passage 27a and the downstream supply oil passage 27b in the crankshaft 2 are disconnected from each other by the partition wall 165 between the inflow hole 175 and the outflow hole 176, so that the upstream supply oil path 27a from the oil pump 44 is cut off. Oil is forced to pass through the torque converter T ′ through the inflow hole 175 and the outflow hole 176, and even if the oil pump 44 has a relatively small capacity, The shortage of hydraulic oil can be prevented as much as possible, and it is effective for small vehicles.
[0123]
  Other configurations are substantially the same as those of the first embodiment, and in FIGS. 15 to 17, the same reference numerals are assigned to the corresponding parts to the first embodiment, and the description thereof is omitted.
[0124]
  The present invention is not limited to the above embodiment, and various design changes can be made without departing from the scope of the invention. For example, GThe lux converters T and T ′ can be replaced with fluid couplings having no torque amplification function.
[0125]
【The invention's effect】
  As described above, according to the first aspect of the present invention, the crankshaft of the engineA multi-stage transmission housed in a crankcase that supports the crankshaft, the crankshaft projecting outward from the side wall of the crankcase, and theMulti-speed transmission input shaftBetween each outer end ofPump impeller andBit-In a small vehicle transmission device connected via fluid transmission means with a bin impeller,The pump impeller and the turbine impeller of the fluid transmission means are rotatably supported on the outer end portion of the crankshaft, and on the opposite side of the crankcase of the fluid transmission means.The crankshaft and theConnect between pump impellersShift clutchA primary reduction gear is mounted on the crankshaft, and connects between the turbine casing and the input shaft between the crankcase and the turbine impeller.As a result, when the engine is idling and when a speed change operation is performed, the speed change clutch can be turned off to eliminate the creep phenomenon and achieve a light speed change without a torque shock.
[0126]
  In addition, among the primary speed reducer, the fluid transmission means, and the speed change clutch, the primary speed reducer is disposed closest to the side wall of the crankcase, and then the fluid transmission means is disposed next to the primary speed reducer. As a result, the bending moment applied to the crankshaft and the input shaft can be minimized, and the fluid transmission means is heavier than the transmission clutch, but the bending moment applied to the crankshaft can also be minimized by their weight. In combination with the downsizing of the fluid transmission means and the speed change clutch, it is possible to improve the durability of the crankshaft, the input shaft, and the bearings that support them.
[0127]
  According to the second feature of the present invention, since the speed change clutch is configured to be an on / off type having no half clutch area, heat generation and wear of the friction part due to the half clutch are avoided, and the durability of the speed change clutch is improved. Can be improved. Moreover, even if the shift clutch jumps from the off state to the half-clutch region and immediately shifts to the on state, the accompanying torque shock is absorbed by the sliding action of the fluid transmission means, so that the riding comfort can be improved. .
[0128]
  Further according to the third aspect of the present invention, a shift clutch actuator that operates to turn the shift clutch off, an idling sensor that detects an idling state of the engine, and a shift operation of the multi-stage transmission are detected. Since it is configured to operate when each output signal of the shift sensor is generated, the shift clutch can be turned on and off accurately at the time of starting and shifting operation, which can contribute to the improvement of the durability of the clutch. .
[0129]
  Furthermore, according to the fourth aspect of the present invention, a multi-plate friction comprising a plurality of driving friction plates connected to the input side, and a plurality of driven friction plates stacked alternately with these driving friction plates and connected to the output side. An engagement means, a centrifugal mechanism that turns on the multi-plate friction engagement means in response to an increase of the rotational speed on the input side over a predetermined value, and during the shifting of the multi-stage transmission even during operation of the centrifugal mechanism. Since the shift clutch is configured with a clutch-off mechanism that turns off the multi-plate friction engagement means, when the engine is idling, the multi-plate friction engagement means is turned off by a centrifugal mechanism. It is possible to prevent the vehicle from moving forward at a slow speed due to the creep phenomenon of the means, and at the time of shifting, the multi-plate friction engagement means is turned off by the operation of the clutch-off mechanism to surely eliminate the shift shock. It can be.
[0130]
  Furthermore, according to the fifth aspect of the present invention, since the torque capacity of the speed change clutch is set to be equal to or greater than the torque capacity of the fluid transmission means, slippage of the speed change clutch is prevented even in a full load state, and its durability is improved. Can be secured.
[Brief description of the drawings]
FIG. 1 is a side view of a motorcycle according to a first embodiment of the present invention.
FIG. 2 is a longitudinal sectional view of a power unit mounted on the motorcycle.
FIG. 3 is an enlarged vertical sectional view of the power unit transmission device.
4 is a cross-sectional view taken along line 4-4 of FIG. 3;
FIG. 5 is a view taken along arrow 5-5 in FIG. 3;
FIG. 6 is a side view of the transmission device.
7 is an enlarged view showing an outlet valve of the speed change clutch of FIG. 3 in a closed state. FIG.
FIG. 8 is an enlarged view showing the outlet valve in an opened state.
9 is a cross-sectional view taken along line 9-9 in FIG.
10 is a sectional view taken along line 10-10 in FIG. 3;
11 is an enlarged view showing the control valve of the lock-up clutch in FIG. 3 in a closed state.
FIG. 12 is an enlarged view showing the control valve in an open state.
FIG. 13 is a sectional view corresponding to FIG. 3, showing a second embodiment of the present invention.
FIG. 14 is a sectional view corresponding to FIG. 3, showing a third embodiment of the present invention.
FIG. 15 is a side view of a four-wheel buggy according to a fourth embodiment of the present invention.
FIG. 16 is a plan view of the four-wheel buggy, with the power unit section cut vertically.
FIG. 17 is an enlarged longitudinal sectional view of the power unit transmission.
[Explanation of symbols]
Cc, Cc '... shift clutch
E ・ ・ ・ ・ ・ ・ Engine
M ・ ・ ・ ・ ・ ・ Multi-speed transmission
T, T '... Torque converter
1. Crankcase
2 ... Crankshaft
10 ... Input shaft of transmission
14 ... Primary reduction gear
14a ... Drive gear
27a ₂ ... Supply oil passage (upstream of upstream supply oil passage)
27a ₁ ... Second oil passage (downstream of upstream supply oil passage)
40 ....... Shift clutch actuator
41 …… Idling sensor
42... Shift sensor
44 ... Oil pump
136... Support cylinder
138 ... Clutch inner
137-141 ... Multi-plate friction engagement means
135, 143, 144... Centrifugal mechanism
150, 152, 156 ... clutch-off mechanism
167 ... ・ Cover body
168 ... Oil chamber
169... First oil passage (through hole)
171... Second oil passage (outflow hole)
175... Second oil passage (inflow hole)

Claims (8)

A multi-stage transmission (M) housed in a crankcase (1) that supports a crankshaft (2) of the engine (E), the crankshaft (2) projecting outward from the side wall of the crankcase (1), and between the outer end of the input shaft of the multi-stage transmission (M) (10), through a fluid transmitting means including a pump impeller (50)及beauty turbines impeller (51) (T, T ') Connected to a small vehicle transmission,
The pump impeller (50) and the turbine impeller (51) of the fluid transmission means (T, T ′) are rotatably supported on the outer end portion of the crankshaft (2), and the fluid transmission means (T, A shift clutch (Cc, Cc ′) for connecting the crankshaft (2) and the pump impeller (50) on the opposite side of the crankcase (1) of T ′) is mounted on the crankshaft (2),
A primary reduction device (14) for connecting the turbine impeller (51) and the input shaft (10) is disposed between the crankcase (1) and the turbine impeller (51). A small vehicle transmission. The transmission for a small vehicle according to claim 1,
A transmission for a small vehicle, wherein the transmission clutch (Cc) is configured to be an on / off type having no half-clutch region. The transmission for a small vehicle according to claim 2,
A shift clutch actuator (40) that operates to turn off the shift clutch (Cc), an idle sensor (41) that detects an idling state of the engine (E), and a shift operation of the multi-stage transmission (M) A transmission for a small vehicle, characterized in that it is configured to operate when each output signal of the speed change sensor (42) for detecting the occurrence of the shift is detected. The transmission for a small vehicle according to claim 1,
Multi-plate friction engagement means comprising a plurality of drive friction plates (139) connected to the input side and a plurality of driven friction plates (140) stacked alternately with these drive friction plates (139) and connected to the output side ( 137-141), a centrifugal mechanism (135, 143, 144) for turning on the multi-plate friction engagement means (137-141) in response to an increase of the input side rotational speed over a predetermined value, Even when the centrifugal mechanism (135, 143, 144) is in operation, the clutch-off mechanism (150, 152, 144) that turns off the multi-plate friction engagement means (135, 143, 144) when the multi-stage transmission (M) is shifted. 156) and the transmission clutch (Cc ′). The transmission for a small vehicle according to any one of claims 1 to 4,
A transmission for a small vehicle, wherein the torque capacity of the transmission clutch (Cc) is set to be equal to or greater than the torque capacity of the fluid transmission means (T). The transmission for a small vehicle according to claim 1,
  An oil chamber (168) to which lubricating oil from an oil pump (44) is supplied is formed on the outer periphery of the crankshaft (2), and the lubricating oil is supplied from the oil chamber (168) to the transmission clutch (Cc '). The first oil passage (169) and the second oil passage (171, 27a) for supplying lubricating oil to the fluid transmission means (T ') ₂ , 175), and a small vehicle transmission. The transmission for a small vehicle according to claim 6,
The oil chamber (168) is formed in a support cylinder (136) provided in the transmission clutch (Cc ′) so as to surround the crankshaft (2), and the first oil passage is supported by the support. A flow path (171, 27a) formed by a through hole (169) drilled in the cylinder (136) and the second oil path drilled in the crankshaft (2). ₂ , 175). A small vehicle transmission device. The transmission for a small vehicle according to claim 7,
The oil chamber (168) is defined by the crankshaft (2), the support cylinder (136), and a lid (167) that closes the open surface of the support cylinder (136). (168) is a supply oil passage (27a) connected to the discharge port of the oil pump (44) provided on the crankshaft (2). ₁ ), A small vehicle transmission device.

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