JP2518996Y2 - Shaft support structure in transmission mechanism - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a shaft support structure in a transmission mechanism.

<Prior Art> As a crawler traveling device for a mobile agricultural machine, there is known a crawler traveling device that steers the right and left crawler driving directions in a forward or reverse direction.

In the transmission mechanism of such a traveling device, as in the invention described in Japanese Patent Publication No. 57-60988, for example, the internal mechanism is complicated, and especially for the steering shaft that is directly transmitted to the axle, a gear for input is used. A large number of loads will be applied to the steering shaft, such as a clutch installed separately on the left and right, or a gear for reverse rotation input.

<Problems to be solved by the invention> As described above, when a large number of loads are applied to the steering shaft, the steering shaft may be distorted or bent, so that the steering shaft may be thickened. It is necessary to increase the strength of the steering shaft.
Further, since it is necessary to provide a large number of gears on the steering shaft as described above, the steering shaft has to have a long span, which is rather disadvantageous in that distortion and bending are likely to occur.

<Means for Solving the Problems> The present invention for solving the above problems is based on a drive shaft.
In a mobile agricultural machine formed by transmitting the power of 16 to the left and right axles 29, 30 via the center gear 20 of the steering shaft 19 and the left and right side clutch gears 23, 24 engaging and disengaging with the center gear 20,
A reverse rotation shaft 41 transmitted from the drive shaft 16 is provided between the drive shaft 16 and the steering shaft 19, and a friction clutch 4 is provided at both ends of the reverse rotation shaft 41.
6, 47 are provided respectively, and reverse rotation transmission gears 35, 36 that mesh with the output sides of the friction clutches 46, 47 are provided coaxially with the left and right side clutch gears 23, 24, respectively. Supporting parts 33, 34 for supporting the left and right side clutch shafts 25, 26 provided with the transmission gears 35, 36 on the same axis are provided between the side clutch gears 23, 24 and the reverse transmission gears 35, 36. It has a feature.

<Operation> The power of the drive shaft 16 is the center gear provided on the steering shaft 19.
It is transmitted to 20. The side clutch gears 23, 24 are disengaged from the center gear 20 to transmit power to the left and right axles 29, 30. By separately engaging and disengaging the side clutch gears 23 and 24, the left and right sides can be separately transmitted. Also the reverse axis
Power is transmitted from the drive shaft 16 to 41, and the power of the reverse rotation shaft 41 is transmitted to the side clutch gears 23, 24 via the reverse rotation transmission gears 35, 36 by the friction clutches 46, 47 provided at both ends. . Here, the reverse rotation of one axle 29 or axle 30,
Reverse side clutch gear 23 or side clutch gear
This is done by turning off 24 and turning on and off the friction clutches 46, 47 on the reverse side as well.

The load applied to the steering shaft 19 in the driven state occurs at the positions of the side clutch gears 23 and 24, the center gear 20, and the reverse transmission gears 35 and 36. Since the support portions 33, 34 of the steering shaft 19 are located between the side clutch gears 23, 24 and the reverse transmission gears 35, 36, the distance from each load point becomes short, and the amount of bending or distortion decreases. . Further, the reverse rotation transmission gears 35 and 36 are cantilevered, but since the support portions 33 and 34 are close to the reverse rotation transmission gears 35 and 36, they can be supported with low strength.

<Example> Hereinafter, one example will be described in detail with reference to the drawings. FIG. 1 is a sectional view showing an internal mechanism of a traveling power transmission device 1 of a mobile agricultural machine having a crawler traveling device such as a combine.

An input shaft 5 is supported in the case 3, and an input pulley 6 is fixed to a protruding portion of the input shaft 5. The other end of the input shaft 5 extends into the hydraulic continuously variable transmission 7 attached to the outside of the case 3, and the rotation of the input shaft 5 transmitted through the input pulley 6 is changed by the hydraulic continuously variable transmission 7. Output shaft 8
Is output to The hydraulic continuously variable transmission 7 is operated by a main gear shift lever so that the gear can be continuously changed.

A gear 9 is fixed to an output shaft 8 supported in the case 3, and is connected to a gear shaft 12 via a gear 11 meshed with the gear 9.
The driving force is transmitted to the motor. A sub transmission gear 13 that rotates integrally with the gear shaft 12 is attached to the gear shaft 12 so as to be slidable in the axial direction. The sub-transmission gear 13 is composed of gears of three different diameters for three-speed shifting, and is fixed to the transmission shaft 14.
The gears of the step-variable gear 15 mesh with each other.

The medium-speed gear of the transmission gear 15 is a gear 18 fixed to the drive shaft 16.
They also mesh with each other and transmit the driving force to the drive shaft 16.

First, the forward (forward) transmission system will be described. In addition to the gear 18, a gear 17 having a diameter smaller than that of the gear 18 is fixed to the drive shaft 16 and a center gear 20 and teeth which are fixed to the steering shaft 19. I am fit.

Inner teeth 21 and 22 are formed on both left and right side surfaces of the center gear 20, and side clutch gears 23 and 24 mesh with each other in a disengageable manner. The side clutch gears 23 and 24 are integrally and slidably attached to side clutch shafts 25 and 26 that are mounted on the steering shaft 19 on the same axis center, and can slide left and right on the side clutch shafts 25 and 26. As a result, the meshing with the inner teeth 21, 22 of the center gear 20 is disengaged. Output gears 27, 28 provided on the left and right axles 29, 30 mesh with the left and right side clutch gears 23, 24, respectively. Therefore, the driving force of the center gear 20 is transmitted to the axles 29, 30 when the left and right side clutch gears 23, 24 are engaged with the inner teeth 21, 22. The axles 29, 30 extend in the left-right direction from the case 3, and have a sprocket 31 attached to the tip thereof, and the sprocket 31 has a crawler belt 32.
Is wrapped around.

According to the above normal rotation transmission system, as shown in FIG. 2, the side clutch gears 23 and 24 are set to the engaged state, and the friction clutch 46 and
When 47 is turned off, drive shaft 16, gear 17, center gear
20, side clutch gear 23, 24, output gear 27, 28, axle 2
Power is transmitted in the order of 9,30 and the aircraft moves forward.

Next, the reverse (reverse) transmission system will be described. The left and right side clutch shafts 25 and 26 reach the left and right outer sides of the case 3, and reverse rotation transmission gears 35 and 36 are fixed to protruding ends, respectively. Further, inside the left and right reverse rotation transmission gears 35 and 36, support portions 33 and 34 formed of bearings are provided,
The side clutch shafts 25, 26 and the steering shaft 19 are supported simultaneously and on the same axis. The load applied to the steering shaft 19 and the left and right side clutch shafts 25 and 26 is applied from the center gear 20, the side clutch gears 23 and 24, and the reverse rotation transmission gears 35 and 36, but the support portions 33 and 34 are connected to the reverse rotation transmission gears 35 and 36. By providing the side clutch shafts 25, 26 close to the reverse transmission gear 35,
The bending moment applied from 36 can be reduced. Similarly, the positions of the support portions 33, 34 are between the side clutch gears 23, 24 and the reverse transmission gears 35, 36, and the side clutch gear 23, the reverse transmission gear 35, and the side clutch gear 24
Since it is almost equidistant from the reverse rotation transmission gear 36, compared with the case of supporting at both ends of the shaft, the steering shaft 19 and the side clutch shaft 2
There is an advantage that the bending and distortion generated in 5, 26 are uniformized and reduced.

Further, since the reverse rotation transmission gears 35 and 36 are provided outside the case 3, the gear diameter can be increased to increase the reduction ratio, and the friction clutches 46 and 47 output to the reverse rotation transmission gears 35 and 36 can be increased. It is possible to reduce the allowable amount of transmission torque. Therefore, a small friction clutch can be used,
The traveling power transmission device 1 can be reduced in weight and size.

On the other hand, a free rotation gear 42, which is rotatably supported by a reverse rotation shaft 41, meshes with the gear 18 of the drive shaft 16. A switching clutch 43 is also supported on the reverse rotation shaft 41, and the switching clutch 43 is provided so as to rotate integrally with the reverse rotation shaft 41 and to be slidable in the axial direction. The switching clutch 43 is a dog clutch,
Clutch pawls are provided on both sides of the switching clutch 43,
The clutch pawl that meshes with the clutch pawl of the switching clutch 43 is
It is provided inside the free rotation gear 42 and the case 3. The switching clutch 43 is always engaged with the clutch pawl 44 on the free rotation gear 42 side or the clutch pawl 45 on the case 3 side.

When the switching clutch 43 is engaged with the clutch pawl 44 of the free rotation gear 42, the power of the drive shaft 16 is transmitted to the reverse rotation shaft 41 via the free rotation gear 42, and the switching clutch 43 and the clutch pawl 45 are connected. When engaged, the rotation of the reverse rotation shaft 41 is restricted.

Both ends of the reverse rotation shaft 41 reach the outside of the case 3, and input ends of friction clutches 46 and 47 are attached to both ends.
The friction clutches 46, 47 are multi-disc clutches in the device of this embodiment, and clutch cases 50, 51 are provided outside the friction clutches 46, 47.
Is formed, the friction clutches 46, 47 and the reverse transmission gear 35,
36 are covered.

Gears 48, 49 are formed on the output side of the friction clutches 46, 47, and the above-mentioned reverse rotation transmission gears 35, 36 mesh with each other. On the outside of the clutch cases 50, 51, the clutch lever 52,
53 is swingably provided, and the friction clutches 46 and 47 are operated by swinging the clutch levers 52 and 53.

According to the above reverse rotation transmission system, as shown in FIG. 3, the switching clutch 43 is engaged with the free rotation gear 42 side, the side clutch gears 23 and 24 are disengaged, and the friction clutches 46 and 47 are engaged. Drive shaft 16, gear 18, free rotating gear 4
2, switching clutch 43, reverse rotation shaft 41, friction clutches 46, 47, gears 48, 49, reverse rotation transmission gears 35, 36, side clutch shafts 25, 2
6, side clutch gear 23, 24, output gear 27, 28, axle 29,
Power is transmitted in the order of 30, and the aircraft moves backward.

Next, the operation of each part when the steering operation is performed based on the traveling power transmission device 1 will be described. The forward / backward movement is as described above. If you apply the parking brake,
As shown in FIG. 4, the switching clutch 43 is engaged with the clutch pawl 45 on the case 3 side to restrict the rotation of the reverse rotation shaft 41,
The left and right friction clutches 46, 47 are put in the on state. This allows
Braking force acts on the axles 29 and 30, and the aircraft does not move. Also,
When the switching clutch 43 is engaged with the free rotation gear 42 side in the state shown in FIG. 2, a rotational force is applied to the drive shaft 16 in the opposite directions from the forward rotation transmission system and the reverse rotation transmission system, and the axle 2
9,30 will be unable to rotate and will be braked. In this case, it is desirable that the speed ratio of the forward rotation transmission system and the reverse rotation transmission system be the same, and the friction clutches 46 and 47 can be used as a parking brake, and a special parking brake structure is not required.

Next, a case of turning left is described. FIG. 5 shows a transmission system in a left turn turning operation in a high speed traveling state such as when traveling on a road.

First, in the case of turning to the left from the forward state described above with reference to FIG. 2, the left side clutch gear 23 is disengaged and the switching clutch 43 is provided on the case 3 side, as shown in FIG. Engage with the clutch pawl 45. By switching the switching clutch 43, the reverse rotation shaft 41 is brought into a stopped state. Since the right crawler is driving forward, the left crawler is rotated by the forward movement of the right crawler, and the aircraft gradually turns to the left. When the operation amount of the operation portion is increased to swing the clutch lever 52 and the friction clutch 46 is brought into the engaged state, the reverse rotation shaft 41
Is stopped, the transmission system on the left side stops, and the left crawler stops. This allows the aircraft to make a left pivot turn around the left crawler. When turning to the right, the changeover clutch 43 is also put on the case 3 side clutch pawl 45.
The right side clutch gear 24 is disengaged and the friction clutch 47 is engaged.

When the switching clutch 43 is engaged with the clutch pawl 45 on the case 3 side, the reverse rotation shaft 41 is stopped, so that only pivot turning is possible.

FIG. 6 shows a transmission system that makes a left turning turn and a left super turning turn during low speed running during work running. First, in the case of turning to the left from the forward state already described in FIG. 2, as shown in FIG. 6, the left side clutch gear 23 is turned off and the switching clutch 43 is set to the free rotation gear.
The clutch claw 44 provided on the 42 side is engaged. By switching the switching clutch 43, the reverse rotation shaft 41 is always in the reverse rotation state. Since the right crawler is driving forward, the left crawler is rotated by the forward movement of the right crawler, and the aircraft gradually turns to the left. When the operation amount of the operation unit is increased to swing the clutch lever 52 and the friction clutch 46 is brought into a half-clutch state, sliding friction with the friction plate on the reverse rotation shaft 41 side which is rotating in reverse causes sliding of the output side gear 48. The rotation is stopped, the left transmission system stops, and the left crawler stops. This allows the aircraft to make a left pivot turn around the left crawler. When the operation amount of the operation portion is further increased to bring the friction clutch 46 into the completely engaged state, the left transmission system includes the reverse rotation shaft 41, the friction clutch 46, the gear 48, the reverse rotation transmission gear 35,
The side clutch gear 23, the output gear 27, and the axle 29 are arranged in this order, and the power for reverse rotation is transmitted. As a result, the left and right crawler driving directions are reversed, and the aircraft makes a super pivot turn.

With the above-described configuration, it is possible to extremely easily and quickly switch from the solid turning to the super turning with the same amount of operation as in the high-speed running state, and the operation performance is improved. There is. Therefore, it is particularly useful during work traveling in which a fine and quick steering operation is required.

Furthermore, switching from pivot turning to super turning is performed continuously due to changes in the clutch pressure of the friction clutches 46 and 47. There is an advantage that the impact load on each part of the mechanism at the time is extremely reduced.

It should be noted that, if a super-spinning operation is performed in a high-speed running state, the aircraft will suddenly turn, which is dangerous. Therefore, the switching clutch 43 is connected to the case 3 side in conjunction with the high-speed switching operation of the main transmission or the auxiliary transmission. By providing a mechanism for switching to the clutch pawl 45, it is possible to prevent an accident during high-speed traveling.

In the traveling power transmission device 1 described above, the reverse rotation shaft 41 may be omitted, and a brake device may be attached instead of the reverse rotation transmission gears 35 and 36 to form a power transmission device for turning the ground.

<Effect of the Invention> According to the structure of the present invention configured as described above, since the supporting portion is located between the side clutch and the reverse rotation transmission gear, the drive input / output points formed of the gears are substantially even. It is possible to support the steering shaft at a position close to the steering shaft.
Therefore, there is an advantage that the deflection of the steering shaft can be reduced.

Further, since the reverse rotation transmission gear is located outside the support portion, the diameter of the reverse rotation transmission gear can be increased, and the reduction ratio during reverse rotation transmission can be increased. Therefore, the power transmission capacity of the friction clutch can be small, a small friction clutch can be used, and the effect of making the entire mechanism compact and reducing costs can be achieved.

[Brief description of drawings]

FIG. 1 is a sectional view showing an internal mechanism of the traveling power transmission device, FIG. 2 is a power transmission system diagram of the traveling power transmission device showing a high speed or low speed forward traveling state, and FIG. 3 is a reverse traveling state, FIG. Is also the parking brake and the braking state during high-speed traveling, FIG. 5 is the same turning state during road traveling (high-speed traveling), and FIG. Is shown. 16: Drive shaft, 19: Steering shaft 23, 24: Side clutch gear 33, 34: Support part, 35, 36: Reverse rotation transmission gear 46, 47: Friction clutch, 41: Reverse rotation shaft

Claims (1)

(57) [Scope of utility model registration request] 1. A center gear (20) of a steering shaft (19) and left and right side clutch gears (23), (24) for engaging and disengaging the power of a drive shaft (16) with the center gear (20). In the mobile agricultural machine that is transmitted to the left and right axles (29) and (30),
The drive shaft (16) is located between the drive shaft (16) and the steering shaft (19).
The reverse rotation shaft (41) transmitted from the reverse rotation shaft (41) is provided, and the friction clutches (46) and (47) are provided at both ends of the reverse rotation shaft (41) so as to be coaxial with the left and right side clutch gears (23) and (24). Are provided with reverse rotation transmission gears (35) and (36) which mesh with the output sides of the friction clutches (46) and (47), respectively, and the steering shaft (19) and the reverse rotation transmission gears (35) and (36) are provided. Support parts (33) for supporting the left and right side clutch shafts (25), (26) on the same axis,
A shaft support structure in a transmission mechanism in which (34) is provided between the side clutch gears (23), (24) and the reverse transmission gears (35), (36).