GB1579366A - Vehicle for excavating or ground moving purposes - Google Patents

Description

(54) A VEHICLE FOR EXCAVATING OR GROUND MOVING PURPOSES (71) We, KUBOTA, LTD. of 22banchi, 2-chome, Funade-cho, Naniwa-ku, Osaka-shi, Osaka-fu, Japan, a joint stock company duly organized under the laws of Japan, do hereby declare the invention for which we pray that a patent may be granted to us and the method by which it is to be performed, to be particularly described in and by the following statement:- The present invention relates to a vehicle for excavating or ground moving purposes wherein all the ground engaging support wheels are driven.

As the driving mechanism for such vehicle, it is conventional to adopt the so-called "inscribed" or planetary gearing construction for the reduction gearing means provided for each and every wheel close to same as the terminal gearing to receive power from respective front or rear differential gearings. More specifically, the outwardly located annular gear is fixed to and rotates with the wheel, while the center gear is fixed to and rotates with the driving axle extending from the differential gearing as one of the output shafts thereof, and a plurality of intermediate gear wheels are provided, on the respective shafts journaled in fixed positions, for free rotation in meshing with both the annular gear wheel and the center gear wheel.

Such general adoption of the planetary gearing construction is based perhaps on the common recognition of the compactness of the over-all mechanism, compatibility with the requirement of obtaining wide steering angle range of the steerable wheels, and advantage of adopting as many unified parts as possible both in reducing the costs and in simplifying the designing.

However, the planetary gearing construction is rather of complicated structure and is therefore yet expensive even if adopted as the common unified parts. Another drawback of the planetary gearing construction resides in that the level of the driving axles is determined as substantially same as the center of the wheels, without possibility of freely raising same, thus leaving fear of damaging the differential and axle housings, especially in case of the non-steerable wheels which are normally to support heavier load than the steerable wheels and are thus apt to sink down into the soil.

According to the present invention there is provided a vehicle for excavating or ground moving purposes wherein all the ground engaging support wheels are adapted to be driven, comprising front and rear wheels, reduction gearing means provided each of the wheels in juxtaposition thereto and an engine for driving the wheels via the said reduction gearing means, characterized in that either the front or the rear wheels are the steerable wheels and the reduction gearing means provided each of the steerable wheels are each of epicyclic or planetary gearing construction, while the reduction gearing means provided each of the remaining non-steerable wheels are each of externally toothed, wheel train gearing construction.

With such provision of the externally toothed wheel train gearing construction for the non-steerable wheels and of the planetary gearing construction for the steerable wheels, a very favorable vehicle has now been obtained, which is far from any disadvantage with respect to costs, which suffers from no restriction of the wide steering angle range of the steerable wheels and which minimizes the fear of damaging even if the non-steerable wheels may somewhat sink down into the soil under heavy load.

Though the reduction gearing means of two different types are now adopted in contrast with the use of the planetary gearing construction as sole parts in the conventional vehicles, the externally toothed, wheel train gearing construction is much less expensive than the planetary gearing construction, and thus the cost of the over-all vehicle is now rather reduced somewhat than the conventional vehicles. The provision of the planetary gearing construction for the steerable wheels retains the advantage of the wide steering angle range of the steerable wheels, while the provision of the externally toothed wheel train gearing construction for the non-steerable wheels, as are heavily loaded and are therefore apt to sink down in the soil, makes it possible to provide the driving axles for these nonsteerable wheels on proper high level thus to insure safe working even on soft unstable land or on irregular field.

In view that the braking mechanism is normally incorporated in the non-steerable wheels, it is another advantage of adopting here the externally toothed wheel train gearing construction, to be able to incorporate the braking mechanism making use of the substantial free space near a first gear wheel to receive the driving input, thus requiring little additional space and avoiding involving a very much complicated construction.

The invention will now be described further, by way of example, with reference to the accompanying drawings, wherein: Fig. 1 is an over-all plan view of a vehicle according to the present invention; and Fig. 2 Is a schematic diagram of the driving mechanism of the vehicle shown in Fig.

1.

The execution of the present invention is now described in detail with reference to the drawings. Fig. 1 shows in non-limitative manner a four-wheel-drive vehicle with shovel and backhoe, and with the body designated generally at 1. In the illustrated instance, the vehicle comprises an engine 2 mounted on the front side; a manoeuvering or control quarter designated generally at 3; tanks 4 and 5 for the hydraulic oil and fuel, respectively, on either side of the control quarter 3; a shoveling apparatus designated generally at 8 provided outwardly on the front end, comprising arms 6 which may be hydraulically raised and lowered and a shovel 7 which may also in turn be pivotally swung on the arms 6; and a digging apparatus designated generally at 12 provided outwardly on the rear end, comprising a boom 9 as may be raised and lowered on a supporting table which is laterally slidable and retainable in any such laterally located position, an arm 10 as may pivotally swung on the tip of the boom 9, and a bucket 11 as may in turn be pivotally swung on the tip of the arm 10.

Driving mechanism for the vehicle 1 is shown in Fig. 2. Power of the engine 2 is transmitted, via a clutch 12, to a transmission gearing 13. Power take off shafts 14 on either side of the transmission gearing 13 are connected, via respective universal joints 15, with front and rear differential gearings 16, respectively.

Looking first to the rear portion with a pair of wheels 17, axles 18 extending on either side are connected, via respective universal joints 19, with right and left reduction gearing means 20, respectively, of the idential epicyclic or planetary gearing construction. Each gearing means 20 comprises a sun wheel or center gear 25 fixed to output shaft of the universal joint 19 thus to rotate with the axle 18, an outwardly located internally toothed annular gear wheel 26 fixed to the rear wheel 17 thus to rotate therewith, and a plurality of planet or intermediate gear wheels 27 on respective shafts journaled on a fixed housing of this gearing means 20 shown in phantom in Fig.

2, freely to rotate thereon in meshing with both the center gear wheel 25 and the annular gear wheel 26. In this illustrated instance, these rear wheels 17 are intended to be the steerable wheels.

Looking now to the front portion with a pair of wheels 21, axles 22 extending on either side are connected with right and left reduction gearing means 24, respectively, of the identical externally toothed wheel train gearing construction. Each gearing means 24 comprises an externally toothed gear wheel 28 fixed to the front wheel 21 thus to rotate therewith, an externally toothed gear wheel 29 located radially outwardly of the said ear wheel 28, in staggered position in the Illustrated instance, fixed to axle 22 namely output shaft of the front differential gearing 16, and intermediate externally toothed wheel gearing means fixed on a shaft journaled on the housing of this reduction gearing means 24 shown in phantom in Fig. 2, comprising in the illustrated instance an externally toothed gear wheel 30 in mesh with the said gear 28 and an externally toothed gear wheel 31 in mesh with the said gear wheel 29, thus operatively connecting the two gear wheels 28 and 29. Designated at 23 is a braking mechanism provided in the gearing means 24. As is seen, the engine 2 is mounted inwardly and to the side of these non-steerable wheels 21 provided with the externally toothed gearing construction 24.

Alternative to the embodiment as illustrated, another embodiment may as well be constructed with opposite arrangement of the two types of the reduction gearing means, namely with provision of the universal joints on the axles 22 of the front wheels 21 which in this instance are intended as steerable wheels and for which are provided respective reduction gearing means of a planetary gearing construction, while the rear wheels 17 which are now non-steerable wheels are provided with respective reduc tion gearing means of an externally toothed wheel train gearing construction.

WHAT WE CLAIM IS: 1. A vehicle for excavating or ground moving purposes wherein all the ground engaging support wheels are adapted to be driven, comprising front and rear wheels, reduction gearing means provided each of the wheels in juxtaposition thereto and an engine for driving the wheels via the said reduction gearing means, characterized in that either the front or the rear wheels are the steerable wheels and the reduction gearing means provided each of the steerable wheels are each of epicyclic or planetary gearing construction, while the reduction gearing means provided each of the remaining non-steerable wheels are each of externally toothed, wheel train gearing construction.

2. A vehicle as claimed in claim 1, wherein the engine is mounted on the side near the pair of non-steerable wheels which are provided with the reduction gearing means of the externally toothed, wheel train gearing construction.

3. A vehicle for excavating or ground moving purposes wherein all the ground engaging support wheels are driven substantially as herein described with reference to and as illustrated in the accompanying draw ings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (3)

**WARNING** start of CLMS field may overlap end of DESC **. tion gearing means of an externally toothed wheel train gearing construction. WHAT WE CLAIM IS:

1. A vehicle for excavating or ground moving purposes wherein all the ground engaging support wheels are adapted to be driven, comprising front and rear wheels, reduction gearing means provided each of the wheels in juxtaposition thereto and an engine for driving the wheels via the said reduction gearing means, characterized in that either the front or the rear wheels are the steerable wheels and the reduction gearing means provided each of the steerable wheels are each of epicyclic or planetary gearing construction, while the reduction gearing means provided each of the remaining non-steerable wheels are each of externally toothed, wheel train gearing construction.

2. A vehicle as claimed in claim 1, wherein the engine is mounted on the side near the pair of non-steerable wheels which are provided with the reduction gearing means of the externally toothed, wheel train gearing construction.

3. A vehicle for excavating or ground moving purposes wherein all the ground engaging support wheels are driven substantially as herein described with reference to and as illustrated in the accompanying draw ings.