JP4956793B2 - Parallel shaft gear transmission - Google Patents

Description

  The present invention includes an input shaft, a counter shaft and an output shaft which are parallel to each other, and can select one of a plurality of transmission gear sets provided on the input shaft and the counter shaft, and drives the output shaft to the counter shaft. The present invention relates to a coupled parallel shaft type gear transmission.

As such parallel shaft type gear transmissions, conventionally, for example, those described in Patent Document 1 and Patent Document 2 are known.
The parallel shaft type gear transmission described in Patent Document 1 includes an input shaft 51 and an output shaft 52 arranged in a coaxial butt relationship, as indicated by 50 in FIG. 5 (a), and these input / output shafts 51, 52. A counter shaft 53 is provided in parallel with the counter shaft 53.

As clearly shown in FIG. 5 (b), the counter shaft 53 is disposed below the input / output shafts 51 and 52, and a plurality of transmission gear sets 54 are provided on the input shaft 51 and the counter shaft 53.
Of the plurality of transmission gear sets 54, one of them can be selected by a synchromesh mechanism or the like, and the input shaft 51 and the countershaft 53 are connected to each other at a corresponding gear ratio by the selected transmission gear set. And
The output shaft 52 is drivingly coupled to the countershaft 53 via an output gear set 55 at the rear end of the countershaft 53.

In FIG. 5 (a), the parallel shaft gear transmission 50 is disposed immediately after the engine ENG, and the input shaft 51 is drivingly coupled to the crankshaft of the engine ENG by the dry clutch 56.
The output shaft 52 is drivingly coupled to the differential gear device 58 of the left and right drive wheels WHL via a final gear set 57.
In FIG. 5 (a), FLW indicates the vehicle body floor, and GND is the road surface with which the drive wheels WHL are in contact.

  The parallel shaft type gear transmission described in Patent Document 2 includes an input shaft 71, an output shaft 72, and a counter shaft 73 arranged in parallel with each other as shown by 70 in FIG. 6 (a). As clearly shown in (b), the counter shaft 73 is disposed below the input shaft 71, and the output shaft 52 is disposed below the counter shaft 73.

A plurality of transmission gear sets 74 are provided on the input shaft 71 and the countershaft 73, and one of the plurality of transmission gear sets 74 can be selected by a synchromesh mechanism or the like, and input by the selected transmission gear set It is assumed that the shaft 71 and the countershaft 73 are connected to each other with a corresponding gear ratio.
The output shaft 72 is drivingly coupled to the countershaft 73 via an output gear set 75 at the rear end of the countershaft 73.

In FIG. 6 (a), the parallel shaft gear transmission 70 is disposed immediately after the engine ENG, and the input shaft 71 is drivingly coupled to the crankshaft of the engine ENG by the dry clutch 76.
The output shaft 72 is drivingly coupled to a differential gear device 78 of the left and right drive wheels WHL via a final gear set 77.
In FIG. 6 (a), as in FIG. 5 (a), FLW indicates the vehicle body floor, and GND indicates the road surface with which the driving wheels WHL are in contact.
Japanese Patent Laid-Open No. 10-181375 Japanese Patent Laying-Open No. 2005-096688

  In the parallel shaft gear transmission 50 described in Patent Document 1 as shown in FIGS. 5 (a) and 5 (b), the output shaft 52 is coaxially disposed on the input shaft 51 and positioned relatively upward. Therefore, as is apparent from FIG. 5 (a), the rear inclination angle of the power train including the engine ENG and the gear transmission 50 tends to increase, and the power train is poorly mounted on the vehicle.

In order to solve this problem, it is conceivable to increase the in-vehicle level of the differential gear device 58. In this case, however, the drive shaft inclination angle from the differential gear device 58 to the left and right drive wheels WHL increases and the transmission efficiency decreases. Is not practical,
Increasing the in-vehicle level of the differential gear device 58 means increasing the in-vehicle level of the gear transmission 50, which means that the position of the center of gravity of the vehicle is increased, which leads to a decrease in vehicle performance.

  Further, in order to improve the front and rear wheel axle load balance, the parallel shaft type gear transmission 50 described in Patent Document 1 is separated from the engine ENG as shown in FIG. 7 and retracted to a position close to the differential gear device 58 in the vehicle. When installed, the lower level of the parallel shaft gear transmission 50 interferes with the road surface GND due to a decrease in the level of the parallel shaft gear transmission 50 due to the large rearward tilt angle of the power train, and the minimum ground clearance is not established. It becomes impossible to mount in a car.

  Therefore, when the parallel shaft gear transmission 50 described in Patent Document 1 is retracted to a position close to the differential gear device 58 and mounted on the vehicle, the vehicle-mounted level of the differential gear device 58 is avoided in order to avoid the above-described vehicle-mounted inability. As a result, there is a problem that the inclination angle of the drive shaft from the differential gear device 58 to the left and right drive wheels WHL is increased and the transmission efficiency is lowered.

  Moreover, increasing the in-vehicle level of the differential gear device 58 means increasing the in-vehicle level of the gear transmission 50, which means that the position of the center of gravity of the vehicle is increased, and the movement performance of the vehicle is reduced. Invite.

The gear transmission 50 is a parallel shaft type, but the dry clutch 56 is an automatic clutch that is automatically engaged and disengaged, and the selection (shift) of the transmission gear set 54 is related to this. If it is a so-called automatic transmission manual transmission that is automatically performed,
A control valve body 59 for controlling automatic transmission / reduction through automatic engagement / release of the dry clutch 56 and automatic selection (shift) of the transmission gear set 54 is arranged below the gear transmission 50 as shown in FIG. Since this is a common practice, the control valve body 59 makes the above problem even more pronounced.

In this regard, in the parallel shaft gear transmission 70 described in Patent Document 2 as shown in FIGS. 6 (a) and 6 (b), a counter shaft 73 is disposed below the input shaft 71, and the counter shaft Since the output shaft 72 is arranged below 73, the output shaft 72 is positioned at the lower level,
As apparent from FIG. 6 (a), the power train including the engine ENG and the gear transmission 50 does not tilt backward, and the gear transmission described in Patent Document 1 is held by the backward tilt of the power train. The above-described problems do not occur.

However, in the parallel shaft type gear transmission 70 described in Patent Document 2, the input shaft 71 has a high height due to the arrangement of the input shaft 71, the counter shaft 73, and the output shaft 72 described above with reference to FIG. Level arrangement,
The position of the center of gravity of the gear transmission 70 is increased, and it is inevitable that the position of the center of gravity of the vehicle is increased, resulting in a decrease in the vehicle performance.

Further, in order to improve the front and rear wheel axle load balance, the parallel shaft type gear transmission 70 described in Patent Document 2 is separated from the engine ENG and retracted to a position close to the differential gear device 58 as shown in FIG. When mounted on
Due to the above-described high level arrangement of the input shaft 71, the upper part of the parallel shaft gear transmission 70 greatly interferes with the vehicle body floor FLW as shown in FIG. As a result, the volume of the passenger compartment decreases.

  Incidentally, when the gear transmission 70 is an automatic transmission manual transmission, the control valve body 79 in FIG. 8 is controlled through automatic engagement / release of the dry clutch 76 and automatic selection (shift) of the transmission gear set 74. The automatic transmission control is performed under the gear transmission 70.

  In view of the problems described above with reference to FIGS. 5 and 7, the present invention follows the lower arrangement of the output shaft based on the fact that the output shaft should be positioned below the input shaft. The purpose is to propose a parallel-shaft gear transmission that is devised so as not to cause the problems described above with reference to FIGS. 6 and 8 by taking measures to position the input shaft at a relatively low level. To do.

For this purpose, the parallel-shaft gear transmission according to the invention is constructed as described in claim 1.
First, a parallel shaft gear transmission which is a premise of the present invention is:
The input shaft, counter shaft, and output shaft that are parallel to each other are provided, and one of a plurality of transmission gear sets provided on the input shaft and the counter shaft can be selected, and the output shaft is driven to the counter shaft by the output gear set. It is a combined type.

The present invention provides such a parallel shaft gear transmission,
The output shaft is disposed below the input shaft when viewed in the axial direction of the input / output shaft and the counter shaft,
The counter shaft is disposed above the output shaft, and is offset in a direction away from the surface passing through the axis of the input / output shaft ,
At the shaft end of the countershaft, the drive coupling of the output shaft to the countershaft is performed, and the output shaft extends in a direction opposite to the extending direction of the countershaft,
A control valve body of a parallel shaft gear transmission is disposed in a space generated below the input shaft and the countershaft due to the offset of the countershaft, and the output gear set is viewed in the axial direction of the control valve body. And are arranged so as to overlap with each other.

In the parallel shaft type gear transmission according to the present invention described above, the output shaft is disposed below the input shaft when viewed in the axial direction of the input / output shaft and the counter shaft.
Due to the lower arrangement of the output shaft, the parallel-shaft gear transmission is positioned relatively upward, and the rearward tilt of the power train including the parallel-shaft gear transmission can be avoided or reduced. The in-vehicle performance of the train can be improved.

  Therefore, there is no need to increase the in-vehicle level of the differential gear device for avoiding or reducing the backward inclination of the power train including the parallel shaft gear transmission, and as a result, the inclination angle of the drive wheel drive shaft is increased and the transmission efficiency is increased. Can be avoided, and the problem that the position of the center of gravity of the vehicle increases and the vehicle motion performance decreases can be avoided.

  Even when the parallel-shaft gear transmission is retracted to a position close to the differential gear device to improve the front and rear wheel axle load balance and is mounted on the vehicle, it is caused by the avoidance of the rear tilt of the power train or the decrease of the rear tilt. Thus, the level of the parallel-shaft gear transmission hardly decreases, and the problem that the lower part of the parallel-shaft gear transmission interferes with the road surface and cannot be mounted on the vehicle can be avoided.

Therefore, there is no need to increase the vehicle-mounted level of the differential gear device in order to avoid the vehicle-mounted impossibility, thereby avoiding the problem that the drive wheel drive shaft has a large inclination angle and the transmission efficiency decreases. .
Moreover, the fact that there is no need to increase the vehicle-mounted level of the differential gear device as described above means that the vehicle-mounted level of the parallel shaft gear transmission does not increase, and avoids an increase in the center of gravity position of the vehicle. As a result, there is no adverse effect that the motor performance of the vehicle deteriorates.

In the present invention, the counter shaft is disposed above the output shaft arranged as described above, and is offset in a direction away from the surface passing through the axis of the input / output shaft.
The input shaft located at the uppermost position of the input / output shaft and the countershaft is lowered in level by the offset of the countershaft, and the input shaft is brought closer to the output shaft located at the lowermost position of the input / output shaft and the countershaft. As a result, the vertical dimension of the parallel shaft gear transmission is reduced.

  The lowering of the level of the uppermost input shaft leads to the lowering of the center of gravity of the parallel shaft gear transmission, and contributes to the lowering of the center of gravity of the vehicle, thereby improving the vehicle motion performance. .

Further, when the parallel shaft type gear transmission of the present invention is mounted on a vehicle by moving it back to a position close to the differential gear device in order to improve the front and rear wheel axle load balance,
The lowering of the level of the uppermost input shaft can prevent the upper part of the parallel shaft gear transmission from interfering with the vehicle body floor, and it is not necessary to provide a large vehicle body floor tunnel on the vehicle body floor to avoid this interference. The problem that the vehicle interior space is sacrificed in the vehicle body floor tunnel can be avoided.
In addition, in this embodiment, the drive coupling between the counter shaft and the output shaft via the output gear set is performed at the shaft end of the counter shaft, and the output shaft is extended in the direction opposite to the extending direction of the counter shaft. Let
A control valve body of a parallel shaft type gear transmission is disposed in a space generated below the input shaft and the countershaft due to the offset of the countershaft, and the output gear set is viewed when the control valve body is viewed in the axial direction. Because it is arranged to overlap (overlapping),
Even with the presence of the control valve body, it is possible to prevent the vertical dimension of the parallel shaft gear transmission from becoming large due to the effective use of the space and the axial overlap of the control valve body with respect to the output gear set. It is possible to prevent the mountability of the parallel shaft gear transmission from being lowered due to the control valve body.

Hereinafter, embodiments of the present invention will be described in detail based on examples shown in the drawings.
1 (a) and 1 (b) show a power train of a front engine / rear wheel drive vehicle (FR vehicle) equipped with a parallel shaft gear transmission 10 according to an embodiment of the present invention, and ENG is a prime mover. The WHL is the left and right rear wheels (left and right drive wheels), GND is the road surface, and FLW is the vehicle floor.

As is apparent from the actual configuration shown in FIGS. 2 and 3, the parallel shaft type gear transmission 10 of the present embodiment is configured such that the input shaft 11, the output shaft 12, and the counter shaft 13 are respectively connected to the respective axes O1, O2, O3. Are arranged so that they are parallel to each other.
1 (b) and FIG. 3, when viewed in the axial direction of the input / output shafts 11, 12 and the counter shaft 13, the output shaft 12 is disposed below the input shaft 11, and the counter shaft 13 is Arranged above the output shaft 12.
Further, as shown in FIG. 1 (b) and FIG. 3, the countershaft 13 has a surface M through which it passes through the axes O1 and O2 of the input / output shafts 11 and 12, that is, the surface indicated by M in FIG. Place it offset in the direction away from it.

A plurality of transmission gear sets 14 are provided on the input shaft 11 and the counter shaft 13, and the plurality of transmission gear sets 14 include a plurality of gears provided on the input shaft 11 and a plurality of gears provided on the counter shaft 13. The gears are configured so that the corresponding gears are always meshed with each other.
A plurality of gears provided on the input shaft 11 are integrally formed or integrally coupled with the input shaft 11 so as to rotate together with the input shaft 11, and a plurality of gears provided on the counter shaft 13 are disposed so as to be rotatable relative to the counter shaft 13. To do.

A plurality of gears provided on the countershaft 13 so as to be rotatable relative to each other can be appropriately coupled to the countershaft 13 by a synchromesh mechanism or the like.
Thus, one of the plurality of transmission gear sets 14 can be selected by the synchromesh mechanism or the like, and the input shaft 11 and the countershaft 13 are driven to each other at a corresponding gear ratio by the selected transmission gear set. Shall be combined.

  The output shaft 12 is drivingly coupled to the countershaft 13 via the output gear set 15 at the rear end of the countershaft 13.

In FIG. 1 (a), in order to improve the front / rear wheel axle load balance, the parallel shaft gear transmission 10 is separated from the engine ENG and moved back to the vicinity of the left and right drive wheels WHL. Drive coupled to the crankshaft of engine ENG by shaft P1.
The output shaft 12 is drivingly coupled to the differential gear device 18 of the left and right drive wheels WHL via the final gear set 17.

  As described above, when the parallel shaft gear transmission 10 is separated from the engine ENG and retracted to the vicinity of the left and right drive wheels WHL, the parallel shaft gear transmission 10 is configured to include the differential gear device 18 as an integrated unit. This is advantageous because it reduces the number of parts.

By the way, in this embodiment, the dry clutch 16 is an automatic clutch that is automatically engaged / released, and the selection (shift) of the transmission gear set 14 in relation to the automatic engagement / release of the clutch 16 is performed. And the parallel shaft gear transmission 10 is used as a so-called automatic transmission manual transmission,
As shown in FIGS. 1 (a) and 2, the shift control valve body 19 for controlling the automatic shift control through the automatic engagement / release of the dry clutch 16 and the automatic selection (shift) of the transmission gear set 14 is shown in FIGS. It is arranged at the lower part of the parallel shaft gear transmission 10.

As is apparent from FIGS. 1 (a) and 2, when the shift control valve body 19 is disposed, the shift control valve body is formed in a space formed below the input shaft 11 and the counter shaft 13 due to the offset of the counter shaft 13. The body 19 is accommodated , and the transmission control valve body 19 is arranged so that a part thereof overlaps (overlaps) with the output gear set 15 when viewed in the axial direction of the input shaft 11 and the counter shaft 13 .
In this case, the control valve body 19 is exposed to the outside simply by removing the oil pan 20 (see FIG. 2) in the lower part of the parallel shaft gear transmission 10 and can be easily removed for repair or maintenance. In addition to the fact that the control valve body 19 for shifting can be improved , the parallel shaft gears can be effectively used due to the above-mentioned space and the axial direction overlap arrangement of the control valve body 19 for shifting with respect to the output gear set 15. It is possible to suppress an increase in the vertical dimension of the transmission, and it is possible to prevent the mountability of the parallel shaft gear transmission from being lowered due to the control valve body.

The parallel shaft gear transmission 10 described above can be arranged as shown in FIG. 4 instead of the arrangement shown in FIG.
That is, the parallel shaft gear transmission 10 is disposed immediately after the engine ENG and integrated therewith, and the input shaft 11 is drivingly coupled to the crankshaft of the engine ENG by the dry clutch 16.
The output shaft 12 is drivingly coupled to the differential gear device 18 of the left and right drive wheels WHL via the propeller shaft P2 and the final gear set 17.

In the parallel shaft type gear transmission 10 according to the above-described embodiment, the output shaft 12 is disposed below the input shaft 11 when viewed in the axial direction of the input / output shafts 11 and 12 and the counter shaft 13, so that
Due to the lower arrangement of the output shaft 12, the parallel shaft gear transmission 10 is positioned relatively upward, and the rearward inclination of the power train including the engine ENG and the parallel shaft gear transmission 10 is shown in FIG. As shown in FIG. 4, it can be avoided, or the backward inclination of the power train can be reduced at least, and the on-board performance of the power train can be improved.

  Accordingly, there is no need to increase the in-vehicle level of the differential gear device 18 for avoiding or reducing the rearward tilt of the power train including the engine ENG and the parallel shaft gear transmission 10, and as a result, the tilt angle of the drive wheel drive shaft is reduced. It is possible to avoid the problem that the transmission efficiency is reduced due to the increase, and the problem that the vehicle center of gravity is increased and the vehicle motion performance is reduced can be avoided.

When the parallel shaft gear transmission 10 is mounted on a vehicle in a state of being separated from the engine ENG and retracted to a position close to the differential gear device 18 as shown in FIG. However, the level of the parallel shaft gear transmission 10 is hardly lowered due to the avoidance of the backward tilt of the power train or the decrease of the backward tilt, and the lower part of the parallel shaft gear transmission 10 interferes with the road surface. The problem that the vehicle cannot be mounted can be prevented.
This effect can be reliably achieved even when the parallel shaft gear transmission 10 is used as an automatic transmission manual transmission and the shift control valve body 19 is built in the lower part of the parallel shaft gear transmission 10.

Therefore, there is no need to increase the vehicle-mounted level of the differential gear device 18 in order to avoid the in-vehicle inability, thereby avoiding the problem that the transmission wheel drive shaft has a large inclination angle and the transmission efficiency is lowered. it can.
Moreover, the fact that the vehicle-mounted level of the differential gear device 18 does not need to be increased as described above means that the vehicle-mounted level of the parallel shaft gear transmission 10 does not increase, and the center of gravity position of the vehicle is increased. This avoids the adverse effect of reducing the vehicle performance.

In this embodiment, as shown in FIG. 1 (b) and FIG. 3, the counter shaft 13 is arranged above the output shaft 12 arranged as described above, and the surface M passing through the axis of the input / output shafts 11, 12 is used. Since the offset in the direction away from the surface M,
The input shaft 11 located at the uppermost position among the input / output shafts 11 and 12 and the countershaft 13 is lowered by the offset of the countershaft 13 to be positioned at the lowermost position among the input / output shafts 11 and 12 and the countershaft 13. As a result, the parallel shaft type gear transmission 10 can be flattened due to a reduction in the vertical dimension to improve the in-vehicle performance as well as the vehicle interior space. Expansion, trunk room volume, and auxiliary equipment storage space.

  The lowering of the level of the input shaft 11 located at the uppermost position leads to lowering of the center of gravity of the parallel shaft gear transmission 10 and contributes to lowering of the center of gravity of the vehicle, thereby realizing improvement in vehicle motion performance. Can do.

Further, when the parallel shaft type gear transmission 10 of the present embodiment is retracted to a position close to the differential gear device 18 as shown in FIG.
The above level reduction of the uppermost input shaft 11 can prevent the upper part of the parallel-shaft gear transmission 10 from interfering with the vehicle body floor FLW, and in order to avoid this interference, it is necessary to provide a large vehicle body floor tunnel on the vehicle body floor FLW This eliminates the problem that the vehicle interior space is sacrificed by a large vehicle floor tunnel.

In addition, these operational effects, that is, the improvement in vehicle motion performance obtained by the reduction in the center of gravity position (vehicle center of gravity position) of the parallel shaft gear transmission 10 due to the reduction in the level of the input shaft 11, and also the reduction in the level of the input shaft 11 Expansion of vehicle interior space
The offset shown in FIG. 1 (b) and FIG. 3 of the countershaft 13 is determined by the mutual approach of the input / output shafts 11 and 12 due to the offset. Of course, when it is performed in such a manner that it is maximized within a range in which the mutual interference of the components does not occur, it can be most prominent.

1 shows a drive system of a front engine / rear wheel drive vehicle equipped with a parallel shaft gear transmission according to an embodiment of the present invention at the rear of the vehicle, (a) is a schematic side view thereof, and (b) is a parallel shaft. It is explanatory drawing which shows the shaft arrangement | positioning seen from the back of a type | formula gear transmission. FIG. 2 is a longitudinal side view showing the actual configuration of the parallel-shaft gear transmission in FIG. FIG. 3 is a front view showing the relative positions of the input / output shaft and the countershaft when the parallel shaft type gear transmission having the actual configuration shown in FIG. 2 is viewed from the front. FIG. 2 is a schematic side view similar to FIG. 1 (a), showing a drive system of a front engine / rear wheel drive vehicle provided with a parallel shaft gear transmission according to the same embodiment immediately after the engine. 1 shows a drive system of a front engine / rear wheel drive vehicle equipped with a conventional parallel shaft type gear transmission immediately after the engine, (a) is a schematic side view similar to FIG. It is explanatory drawing which shows the shaft arrangement | positioning seen from the back of a parallel shaft type gear transmission. (A) is a schematic side view similar to FIG. 1 (a), showing the drive system of a front engine / rear wheel drive vehicle equipped with another conventional parallel shaft gear transmission immediately after the engine. ) Is an explanatory view showing a shaft arrangement as viewed from the rear of the parallel shaft type gear transmission. FIG. 6 is a schematic side view similar to FIG. 1 (a), showing a drive system of a front engine / rear wheel drive vehicle in which the conventional parallel shaft gear transmission shown in FIG. 5 (a) is separated from the engine and arranged rearward. . FIG. 6 is a schematic side view similar to FIG. 1 (a), showing a drive system of a front engine / rear wheel drive vehicle in which the conventional parallel shaft gear transmission shown in FIG. 6 (a) is separated from the engine and arranged rearward. .

Explanation of symbols

10 Parallel shaft gear transmission
11 Input shaft
12 Output shaft
13 Counter shaft
14 Transmission gear set
15 Output gear set
16 Dry clutch (automatic clutch)
17 Final gear set
18 Differential gear unit
19 Shift control valve body
20 Oil pan
ENG engine (motor)
WHL left and right drive wheels
GND Road surface
FLW body floor
P1, P2 propeller shaft

Claims (3)

The input shaft, counter shaft, and output shaft that are parallel to each other are provided, and one of a plurality of transmission gear sets provided on the input shaft and the counter shaft can be selected, and the output shaft is driven to the counter shaft by the output gear set. In a coupled parallel shaft gear transmission,
The output shaft is disposed below the input shaft when viewed in the axial direction of the input / output shaft and the counter shaft,
The counter shaft is disposed above the output shaft, and is offset in a direction away from the surface passing through the axis of the input / output shaft ,
At the shaft end of the countershaft, the drive coupling of the output shaft to the countershaft is performed, and the output shaft extends in a direction opposite to the extending direction of the countershaft,
A control valve body of a parallel shaft gear transmission is disposed in a space generated below the input shaft and the countershaft due to the offset of the countershaft, and the output gear set is viewed in the axial direction of the control valve body. A parallel shaft gear transmission characterized in that it is arranged so as to overlap . In the parallel shaft gear transmission according to claim 1,
The parallel shaft type wherein the offset of the countershaft is performed in such a manner that mutual approach of the input / output shafts by the offset is maximized within a range in which mutual interference of the input / output shafts does not occur. Gear transmission. The parallel shaft type gear transmission according to claim 1 or 2 , wherein the input shaft is coupled to a prime mover by an automatic clutch, and selection of a transmission gear set between the input shaft and a countershaft is automatically performed.
2. The parallel shaft gear transmission according to claim 1, wherein the control valve body is a shift control valve body that performs engagement / release control of the automatic clutch and automatic selection of the transmission gear set.

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