JPH065241Y2 - Power extraction structure of agricultural tractor - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention relates to a mid-mount type working device such as a lawn mower mounted between a rear wheel, a front wheel, and front and rear wheels in a mission case at the rear of the machine body, and a machine body. The present invention relates to a power take-out structure of a multipurpose agricultural tractor configured to distribute and supply power to a rear mount type working device such as a tiller mounted on a rear portion.

[Conventional technology]

The following two types of agricultural tractors are known.

(A) In the transmission case, the final gear shaft that is interlocked with the rear wheel differential mechanism, the transmission shaft for extracting rear power that is located below this final gear shaft, and the final gear shaft that is interlocked via a transmission gear A front power transmission shaft and a rear power output power transmission shaft, each of which is provided with a mid power output shaft that is interlocked with a transmission gear via a transmission gear, and the mid power output shaft is disposed immediately below the front power transmission shaft. .

(B) The final transmission shaft that is interlocked with the differential mechanism for the rear wheels, the transmission shaft for extracting rear power that is located below the final transmission shaft, and the transmission for the front wheels that is interlocked with the final transmission shaft in the transmission case. And a first transmission that is interlocked with the final transmission shaft through a transmission gear that is idle-supported by the rear power extraction transmission shaft in the transmission system from the final transmission shaft to the front wheel transmission shaft. A second shaft that is interlocked with the first transmission shaft via a shaft and a transmission gear that is idly supported by the front wheel transmission shaft.
A front wheel transmission including a transmission shaft and a switching operation section for selectively interlocking the transmission shaft for the front wheels and both the transmission shafts.

[Problems to be solved by the invention]

In the case of the former (a) agricultural tractor, there is an advantage that the front wheels can be driven at the same speed as the rear wheels, and the mid-mount type working device and the rear-mount type working device can be freely mounted. Also, in the latter (b) agricultural tractor, only the rear-mounted working device can be installed, but when the machine is turning, the front wheel transmission is operated to reduce the drive peripheral speed of the front wheels. By increasing the driving peripheral speed of the wheels, there is an advantage that the turning radius of the machine body can be reduced and the workability can be improved.

However, a combination of the functions of these two types of agricultural tractors, that is, there is currently no agricultural tractor having a power take-out function and a front wheel speed changing function for the mid-mounting type working device and the rear-mounting type working device, and this kind of At present, there is a demand for the development of agricultural tractors.

An object of the present invention is to realize the above-mentioned demand while suppressing an increase in the size of the mission case in the vertical direction and a decrease in ground clearance.

[Means for solving problems]

The characteristic configuration of the present invention is that a final transmission shaft, which is interlockingly connected to a rear wheel differential mechanism, is provided in a transmission case, a rear power take-out transmission shaft located below the final transmission shaft, and the rear power take-out transmission shaft. A first transmission shaft of a front wheel transmission that is interlockingly connected to the final transmission shaft via a first transmission gear that is idle-supported by the first transmission shaft, and a front-wheel transmission shaft located below the first transmission shaft;
At a position below the front-wheel transmission shaft, a mid-power take-off shaft that is interlockingly connected to the rear power take-off transmission shaft via a second transmission gear that is idly supported by the front-wheel transmission shaft,
A front wheel transmission that is interlockingly connected to the first transmission shaft through a third transmission gear that is idly supported by the front wheel transmission shaft and interlockingly connected to the front wheel transmission shaft through a gear mechanism. The second transmission shafts are respectively provided, and the mid power take-off shaft and the second transmission shaft are separately arranged to the left and right with respect to the front wheel transmission shaft.

[Work]

As described above, the mid power take-off shaft and the second wheel of the front wheel transmission are
By arranging the power transmission shaft and the power transmission shaft for the front wheels separately below the front power transmission shaft, the mid power take-off shaft and the second power transmission shaft of the front wheel transmission and the power transmission shaft for the front wheels are maintained in a predetermined power transmission state. Since the vertical spacing of the three shafts can be reduced, the vertical dimension of the mission case can be reduced accordingly, and
The ground clearance can be large.

[Effect of device]

Therefore, by devising the arrangement of the mid power take-off shaft located at the lowermost part in the mission case and the second transmission shaft of the front wheel transmission as described above, it is possible to suppress the enlargement of the mission case in the vertical direction as much as possible. In addition, the requirements mentioned above could be realized while suppressing the decrease in ground clearance.

〔Example〕

As shown in FIG. 5, a pair of left and right steering type front wheels (1), (1)
And a rear power take-off shaft (4) protruding rearward at the rear part of the mission case (3) disposed at the rear part of the traveling machine body capable of driving each of the unsteered rear wheels (2), (2). ) Is provided, and at the front of the mission case (3), a mid power take-off shaft (5) protruding forward is provided, and a rear power take-off shaft of various working devices such as a rotary tiller connected to the rear of the machine body. (4) Power transmission can be performed, and mid power is taken out to various working devices such as lawn mowers that are suspended between the front wheels (1) and rear wheels (2) and are suspended under the machine. axis
The agricultural tractor is configured so that power can be transmitted via (5).

As shown in FIG. 3, when power from an engine (not shown) is introduced into the mission case (3), the introduced power is transmitted through the clutch (6) to the traveling transmission shaft (7), as well as,
The PT that is fitted to the traveling transmission shaft (7) so as to be relatively rotatable.
The power transmitted to the O transmission shaft (8) and transmitted to the traveling transmission shaft (7) is passed through the main transmission mechanism (9), the forward / reverse switching mechanism (10), and the auxiliary transmission mechanism (11). And the power transmitted to the final transmission shaft (13) interlocked with the rear wheel differential mechanism (12) and transmitted to the PTO transmission shaft (8).
(14) and the rear power take-off transmission shaft (15) for transmission to the rear power take-off shaft (4).

The front wheel transmission (1) in which the power transmitted to the final transmission shaft (13) is provided below the rear power take-out transmission shaft (15)
6), the power transmitted to the front wheels (1), (1) via the front wheel transmission shaft (17) and the power transmitted to the rear power take-off transmission shaft (15) is taken as the mid power take-off shaft. It is configured as follows so as to be transmitted to (5).

That is, as shown in FIG. 1 to FIG. 3, the first transmission gear (18) which is idly supported on the rear power take-off transmission shaft (15).
The first transmission shaft (19) of the front wheel transmission (16), which is interlockingly connected to the final transmission shaft (13) via the third transmission gear (20), which is idle-supported by the front wheel transmission shaft (17). ) Through the first transmission shaft
The front wheel transmission (1) that is linked to (19) and is linked to the front wheel transmission shaft (17) via a gear mechanism (21).
The second transmission shaft (22) of 6) is provided and the gear mechanism (21)
Of the front wheel transmission shaft (17), which is configured to be idle, is provided with a multi-plate friction clutch (23) in a transmission gear (21A), and the third transmission gear (20) is provided with a clutch pawl portion ( 20A), and the front wheel transmission device (16) is configured by attaching a transmission / transmission gear member (25) to the front wheel transmission shaft (17) via a sleeve (24) so as to be integrally rotatable and slidable. I am doing it. When the shifter (26) for slidingly operating the speed change member (25) is operated to the first operation position which is moved to the right from the position shown in FIG. 2, the speed change member (25) causes the clutch claw portion to move. A clutch claw portion (25a) that can be freely engaged and disengaged is provided on (20A), and the third transmission gear
0) integrally rotatably engaged with each other so that the average peripheral speed of the pair of front wheels (1), (1) and the average peripheral speed of the pair of rear wheels (2), (2) are the same or substantially the same. When in the standard transmission state and when the shifter (26) is operated to the second operating position shown in FIG. 2, the speed change member (25) is disengaged from the third transmission gear (20) and the friction clutch (23) is released. Deactivated, a pair of rear wheels (2),
When only the (2) is in the two-wheel drive state, and when the shifter (26) is moved to the third operation position which is moved leftward from the position shown in FIG. 2, the speed change member (25) is operated. Part (25b)
The friction clutch (23) is turned on and operated by the third transmission gear (2
(0) to rotate integrally with the front wheels (1), (1) so that the average peripheral speed is higher than that of the rear wheels (2), (2). There is.

Further, at a position below the front wheel transmission shaft (17), to the rear power take-off transmission shaft (15) via a second transmission gear (27) which is idly supported by the front wheel transmission shaft (17). The mid power take-off shaft (5) connected in an interlocking manner is provided, and the mid power take-off shaft (5) and the second transmission shaft (22) are connected to the front wheel transmission shaft (17).
It is distributed to the left and right with respect to.

The front wheel transmission is attached to a detachable lid (28) that closes an opening formed in the bottom wall of the mission case (3).
(16), the front wheel transmission shaft (17), the mid power take-off shaft
(5) is installed.

As shown in FIG. 4, a pair of front wheels (1), (1) are respectively provided with a pitman arm (31) connected to a steering handle (29) through an interlocking mechanism (30) through a tie rod (32). By rotating the steering handle (29) in conjunction with the knuckle arm (not shown) of the front wheel (1), (1)
Is configured to be steerable.

Then, as shown in FIGS. 1 and 4, the shifter is
Rotation shaft of first swing arm (34) with free end engaged with (26)
A second swing arm (36) fixed to the end of (35) and a swing interlocking member (37) interlocked with the pitman arm (31) via a cam mechanism (not shown) are provided. The front wheels are linked by a wire (38) and an interlocking rod (39).
When the steering angles of (1) and (1) are less than the set value, the swing interlocking member (37) is moved to the first position by the action of the spring (not shown).
(R) is maintained, the front wheel transmission (16) is in the standard state, and when the steering angle of the front wheels (1), (1) is steered below a set value, the swing interlocking operation is performed. The member (37) is swung from the first position (R) to the second position (F) so that the front wheel transmission (16) is automatically switched to the speed increasing transmission state. still,
Although not shown, the front wheel transmission is operated by operating an operation lever for the front wheel transmission (16) to a position where the pitman arm (31) and the second swing arm (36) are disconnected. (16) can be switched to a two-wheel drive state.

An adjusting mechanism for adjusting the pressing force of the speed change member (25) to the friction clutch (23) on the interlocking rod (39).
It is equipped with (40). That is, the interlocking rod (39) is configured as a split type including the first rod portion (39A) and the second rod portion (39B), and the screw portion formed on the second rod portion (39B). Adjustment collar (41) and nut to be screwed into
(42) is fitted on the outside, and a spring (43) is provided in the adjusting collar (41) so as to be located between the inner end surface of the adjusting collar (41) and the inner end surface of the first rod portion (39A). The pressing force of the speed change member (25) can be adjusted by moving and adjusting the adjusting collar (41) in the longitudinal direction of the interlocking rod (39).

Also, the rocking wire (38) and the interlocking rod (39) are connected in a state where the connecting portion of the release wire (38) is located closer to the base end side than the connecting portion of the interlocking rod (39). The moving member (44) is provided to increase the moving amount of the interlocking rod (39) with respect to the moving amount of the release wire (38).

It should be noted that reference numerals are added to the claims of the utility model for convenience of comparison with the drawings, but the present invention is not limited to the structure of the accompanying drawings by the entry.

[Brief description of drawings]

The drawings show an embodiment of the power take-out part structure of an agricultural tractor according to the present invention. FIGS. 1 and 2 are partially cutaway sectional views showing the power take-out part transmission structure, and FIG. 3 shows the inside of a mission case. FIG. 4 is a diagram showing a power transmission structure, FIG. 4 is a side view showing a linkage structure between a steering handle and a front wheel transmission device, and FIG. 5 is a whole side view of an agricultural tractor. (3) …… Mission case, (5) …… Mid power take-off shaft, (12) …… Rear wheel differential mechanism, (13) …… Final transmission shaft, (1
5) …… Transmission shaft for rear power extraction, (16) …… Front wheel transmission, (17) …… Transmission shaft for front wheels, (18) …… First transmission gear, (1
9) …… First transmission shaft, (20) …… Third transmission gear, (21) …… Gear mechanism, (22) …… Second transmission shaft, (27) …… Second transmission gear,
(28) …… Lid.

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Mamoru Kawaguchi 64, Ishizukita-machi, Sakai City, Osaka Prefecture Kubota Iron Works Co., Ltd.Sakai Works (72) Keizo Kato, 64, Ishizukita-machi, Sakai City, Osaka Prefecture Kubota Iron Works Co., Ltd. Inside the Sakai Plant (56) References Open 55-53621 (JP, U) Open 63-179239 (JP, U) Open 54-134430 (JP, U)

Claims (2)

[Scope of utility model registration request] 1. A final transmission shaft (13) interlockingly connected to a rear wheel differential mechanism (12) in a transmission case (3), and for extracting rear power located below the final transmission shaft (13). Transmission shaft (15),
The first which is idled and supported on the rear power take-off transmission shaft (15)
A first transmission shaft (19) of a front wheel transmission (16), which is interlocked with the final transmission shaft (13) through a transmission gear (18), for front wheels located below the first transmission shaft (19) The transmission shaft (17), at a position below the front wheel transmission shaft (17), the front wheel transmission shaft (17)
A mid power take-off shaft (5), which is interlockingly connected to the rear power take-off transmission shaft (15) through a second transmission gear (27) which is idly supported by the front power transmission shaft (17). Third supported
The front wheel transmission (16) which is interlockingly connected to the first transmission shaft (19) through a transmission gear (20) and interlockingly connected to the front wheel transmission shaft (17) through a gear mechanism (21). ) 2nd transmission shaft (2
2) is provided respectively, and the power extraction of the agricultural tractor is such that the mid power extraction shaft (5) and the second transmission shaft (22) are distributed to the left and right with respect to the front wheel transmission shaft (17). Part structure. 2. The front wheel transmission (16), the front wheel transmission shaft
(17) A utility model registration request in which the mid power take-off shaft (5) is attached to a removable lid (28) that closes an opening formed in the bottom wall of the mission case (3) The power take-out part structure of the agricultural tractor according to the first paragraph.