JPH0740410Y2 - Foldable work vehicle - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a front vehicle body having drive-type front wheels, a drive-type rear wheel, and an engine positioned above a differential mechanism for rear wheels. A rear vehicle body having the same is connected so as to be relatively swingable about a longitudinal axis, and an output shaft of a traveling transmission device, a first input shaft of a front wheel differential mechanism, and a second wheel of the rear wheel differential mechanism. The input shaft is arranged so as to match or substantially match the center of the vehicle body left and right, the output shaft and the first input shaft are connected by a rotary shaft with a universal joint, and the output shaft and the second input shaft are connected. Front wheels that are connected and have the front and rear wheel actuation mechanisms
The present invention relates to a body-folding work vehicle in which axle cases are continuously provided at both left and right ends of a rear wheel transmission case.

[Conventional technology]

The body-folding type work vehicle described above has the universal joint of the rotary shaft with the universal joint in a non-bent state when the vehicle body is not folded, To ensure that the left and right body bending angles are as large as possible and to directly connect the output shaft of the traveling transmission and the second input shaft of the rear wheel differential mechanism so that they can be connected as close as possible. In addition, the arrangement for the output shaft, the first input shaft and the second input shaft is adopted.

In this type of work vehicle, conventionally, final deceleration between the output shaft of the traveling transmission and the rear wheels is performed only by the rear wheel differential mechanism.

[Problems to be solved by the device]

Conventionally, since the reduction ratio of the final deceleration is not set to a predetermined value, the diameter of the final gear of the rear wheel differential mechanism becomes relatively large, and as a result, the rear wheel transmission case incorporating the rear wheel differential mechanism is installed. The diameter of the rear wheel was large and the ground clearance of the rear wheel transmission case was low. Further, when the engine is arranged such that the engine output axis is located at the center of the vehicle body in the left-right direction or substantially in the center of the left-right direction and the engine weight is applied to the left and right wheels as evenly as possible, the engine installation level is relatively high due to the large diameter of the transmission case. However, there is a disadvantage that the center of gravity of the entire vehicle becomes high.

An object of the present invention is to remodel the rear wheel transmission case so that the height above the ground can be maximized and the engine can be mounted while being positioned at a low level in the left and right center of the vehicle body.

[Means for Solving the Problems]

In order to achieve the object of the present invention, in the body-folding type work vehicle described at the beginning, the traveling transmission is linked to the engine through a hydraulic continuously variable transmission to provide the front and rear wheels. A pair of front and rear planetary speed reduction mechanisms that individually decelerate the rotational output of the differential mechanism to the left and right front wheels / rear wheels are provided, and the axis of the planetary speed reduction mechanism is the front wheel / rear wheel differential mechanism. The output shaft core and the front and rear wheel shaft cores are positioned so as to be concentric with each other, and are separately mounted in the left and right axle cases, respectively, and the output shaft core of the engine matches the left and right center of the vehicle body. Alternatively, the engine is arranged in a state of substantially matching. The action and effect are as follows.

[Action]

The diameter of the final gear of the differential mechanism for the rear wheels is made smaller than before, and even if the deceleration by the final gear is insufficient for this reason, the two-stage deceleration of the deceleration by the final gear and the deceleration by the planetary deceleration mechanism Therefore, the rear wheel final reduction ratio can be set to a desired value. It is possible to make the reduction gear between the rear wheel differential mechanism and the rear wheels a planetary type reduction mechanism rather than a non-planetary type reduction mechanism, and to make the final gear diameter smaller.

Then, by reducing the diameter of the final gear and installing the planetary reduction mechanism concentrically with the differential mechanism output shaft core and the rear wheel shaft core, the ground clearance of the rear wheel transmission case becomes as high as possible, and The diameter of the rear wheel transmission case can be made as small as possible so that the engine output axis matches or matches the center of the vehicle body left and right and the engine can be installed at the lowest level.

Moreover, the planetary reduction mechanism is positioned so that the axis of the planetary reduction mechanism is concentric with the output axis of the front wheel / rear wheel differential mechanism and the front wheel / rear wheel axis. In this state, the left and right axle cases are separately equipped, so compared to the case where a planetary speed reduction mechanism is installed in the gear case near the inner parts of the front and rear wheels, It is possible to widen the space around the axle and avoid narrowing the space above, below, left and right of the axle.

Further, since the traveling transmission device is linked to the engine via the hydraulic continuously variable transmission, the structure can be simplified as compared with the case where the traveling transmission device is linked to the engine via only the gear transmission.

[Effect of device]

Due to the planetary reduction mechanism and its concentric arrangement, the rear wheel transmission case can be made smaller, and the ground height of the rear wheel transmission case as the minimum ground height of the vehicle can be maximized, and the engine can be centered on the left and right of the vehicle body. It can be installed at a position as low as possible,
It was possible to avoid the narrowing of the space above and below and to the left and right of the axle, and it was possible to work safely on rough terrain, and also to make the structure around the power transmission device compact.

〔Example〕

 Next, examples will be shown.

As shown in FIG. 6, a front vehicle body having a drive type front wheel (1) and a shovel device (2), a drive type rear wheel (3), a driving part (4) and a driver's seat (5) are provided. The rear vehicle body and the rear vehicle body are connected so as to swing relative to each other around the longitudinal axis (X), and the front vehicle body is swung with respect to the rear vehicle body by the steering cylinder (6) to steer the vehicle body. The wheel loader is formed into a broken body.

To enable driving of the front wheels (1) and rear wheels (3),
As shown in FIGS. 1 and 2, a gear transmission type transmission (8) is interlocked with an engine (E) through a hydraulic continuously variable transmission (7), and the transmission ( 8) The front end side of the output shaft (9) provided at the lower end side of the output shaft (9) aligned with the center of the vehicle body (CB) and oriented in the vehicle front-rear direction, and the universal joints (10) provided at both front and rear sides The first input shaft (13) of the front wheel differential mechanism (12) by the rotating shaft (11)
And is configured to transmit the left and right rotational outputs of the front wheel differential mechanism (12) to the left front axle (1a) or the right front axle (1b) via the reduction gear mechanism (14a) or (14b). The rear end side of the output shaft (9) is connected to the second input shaft (16) of the rear wheel differential mechanism (15), and the left and right rotation of the rear wheel differential mechanism (15) is performed. Output reduction mechanism (17a)
Alternatively, it is configured to be transmitted to the left rear axle (3a) or the right rear axle (3b) via (17b).

The first input shaft (13) and the second input shaft (16) are the output shaft (9)
In the same manner as above, the first input shaft (13), the second input shaft (16) and the output shaft (9) are arranged so as to match the center (CB) of the vehicle body in a plan view or in a plan view. By being configured so as to be concentric both in the front-back direction, the universal joint (10) of the rotating shaft (11) becomes unbent or close to this in a plan view when the vehicle body is in the non-bending state. In this way, the output shaft (9) and the second input shaft (16) are directly connected.

As shown in FIG. 3 and FIG. 5, the engine (E) is set in a state in which the output shaft core (CE) of the engine (E) is aligned with the left-right center (CB) of the vehicle body and the rear wheel differential mechanism (15). ), And is attached to the left and right vehicle body main frames (18), (18) via cushioning rubber (not shown).

As shown in FIG. 4, the input shaft (19) is included in each of the speed reducing mechanisms (14a), (14b) and (17a), (17b).
Is formed in the same part as the output shaft (12a) of the front wheel differential mechanism (12) or the output shaft (15a) of the rear wheel differential mechanism (15),
The output shaft (20) is formed in the same part as the front axle (1a) or (1b) or the rear axle (3a) or (3b) and is arranged concentrically with the input shaft (19), and the input shaft gear portion (19
a) and the sun gear (21), the planetary gear (2
2) and a carrier (24) that supports the planetary gear (22) via a support shaft (23), thereby forming an input shaft (19) and an output shaft (2).
0) and are linked. That is, the front wheel differential mechanism (1
2) Or the planetary type so that the rotational output of the rear wheel differential mechanism (15) is reduced by the action of the planetary gear (22) and transmitted to either the left or right front wheel (1) or rear wheel (3). And is positioned concentrically with the output shaft core (FD) and the front wheel shaft core (F) of the front wheel differential mechanism (12), or of the rear wheel differential mechanism (15). It is configured to be concentric with the output shaft core (FD) and the rear wheel shaft core (R).

That is, the rotation output of the traveling transmission device (8) is reduced by the final gear (12b) or (15b) of the differential mechanism (12) or (15) and the reduction mechanism (on the front wheel side or the rear wheel side). 14a) or (14b) or (17a) or (17
The final deceleration is transmitted by the two-step deceleration including the deceleration by b) and is transmitted to the wheel (1) or (3). Then, by expressing the final reduction ratio by two-step deceleration,
The final gears (12b) and (15b) are formed in a small diameter gear having a relatively small reduction ratio, and the front wheel transmission case (25) and the rear wheel transmission case (26) are formed in a small case having a relatively small outer diameter. Transmission case (25) and rear wheel transmission case (26)
It is possible to install the engine (E) at the lowest level while making the ground clearance of the vehicle as high as possible.

Axle cases (29), (29), are attached to the left and right ends of the front and rear wheel transmission cases (25) and (26), respectively, in which the front and rear wheel actuation mechanisms (12) and (15) are separately installed. (30) and (30) are arranged in series, and these axle cases (29) and (2
9), (30), and (30) include the planetary reduction mechanism (14a),
(14b), (17a), and (17b) are installed, respectively.

Reference numeral (27) shown in FIG. 5 is an exhaust muffler for the engine, which is attached to the lower portion of the engine (E) so as to be supported through the attachment stay (28).

Reference numerals are given in the claims of the utility model for convenience of comparison with the drawings, but the invention is not limited to the structures of the accompanying drawings by the entry.

[Brief description of drawings]

The drawings show an embodiment of a folding-type work vehicle according to the present invention. Fig. 1 is a plan view of a transmission system, Fig. 2 is a sectional view of a transmission for traveling, and Fig. 3 is a front view of an engine mounting portion. FIG. 4 is a cross-sectional view of the differential mechanism and the planetary speed reducer, FIG. 5 is a side view of the driving part, and FIG. 6 is a side view of the entire wheel loader. (1) ... front wheel, (3) ... rear wheel, (7) ... hydraulic type continuously variable transmission, (8) ... traveling transmission device, (9) ...
… Output shaft, (11) …… Rotary shaft, (12) …… Front wheel differential mechanism, (13) …… First input shaft, (15) …… Rear wheel differential mechanism, (16) …… 2nd input shaft, (17a), (17b) …… Planetary reduction mechanism, (25) …… Front wheel transmission case, (26) …… Rear wheel transmission case, (29) …… Axle case, (30)… … Axle case, (X) …… Vertical axis, (E) …… Engine, (C
B) …… Center of the vehicle body left and right, (CE) …… Engine output shaft core,
(FD) ... Output shaft core of front wheel differential mechanism, (RD) ... Output shaft core of rear wheel differential mechanism, (F) ... Front wheel shaft core, (R) ...
... rear wheel axle core.

Claims (1)

[Scope of utility model registration request] 1. A front body having drive-type front wheels (1),
A drive type rear wheel (3) and a rear vehicle body having an engine (E) located above the rear wheel differential mechanism (15) are connected so as to be relatively swingable around a vertical axis (X). An output shaft (9) of the traveling transmission (8), a first input shaft (13) of the front wheel differential mechanism (12), and a second input shaft of the rear wheel differential mechanism (15) ( 16) is arranged so as to match or substantially match the center (CB) of the vehicle body, and the output shaft (9) and the first input shaft (13) are connected by a rotary shaft (11) with a universal joint, and , A front wheel / rear wheel transmission case (25) that connects the output shaft (9) and the second input shaft (16) and separately houses the front wheel / rear wheel actuation mechanisms (12) and (15), respectively. Axle cases (29), (29), (30), (3
0) is a body-folding work vehicle in which the traveling transmission device (8) is interlockingly connected to the engine (E) via a hydraulic continuously variable transmission (7), A front-rear pair that separately transmits the rotational outputs of the front / rear differential mechanism (12), (15) to the left and right front / rear wheels (1), (1), (3), (3), respectively. Each planetary speed reducer (14
a), (14b), (17a), and (17b) are the planetary reduction gear mechanisms (14a), (14b), (17a), and (17b) whose axial cores are the front wheel / rear wheel differential mechanism. (12), (15) output shaft core (F
D), (RD), and the left and right axle cases (29), (29), () while being positioned so as to be concentric with the front wheel / rear wheel axis cores (F), (R), respectively. 30) and (30) are separately installed, and the engine (E) is arranged in such a manner that the output shaft core (CE) of the engine (E) matches or substantially matches the left-right center (CB) of the vehicle body. A torso-shaped work vehicle.