JPH11321726A - Tractor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce a front rise and improve a wet field performance by making right/left front wheels a rubber tyre with a lug on its tread and a semicrawler a rubber crawler. SOLUTION: The caterpillar 16 of right/left semicrawlers 3 is constituted by a rubber crawler. A front earth length L1 is large and a rear earth length L2 is small by making a vertical line V-V through the axis of a rear wheel 11 a base and a front/rear weight balance is ensured and the turn steering while lifting a work machine is made favorable and the sufficient earth length is ensured at the working time while lowering the work machine and the side slip at the slant land is obstructed. The right/left front wheels 2 of the frontside are constituted of a pneumatic rubber tyre with a lug 2A on its tread and the balance of a drive force between right/left semicrawlers 3 of the rearside is ensured. Them, the turning radius is minified and the turning performance can be improved while keeping the front/rear balance of the drive force favorable and a wet field performance also can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a tractor,
More specifically, the present invention relates to an improvement of a traveling device including left and right front wheels on the front side and left and right semi crawlers on the rear side.

[0002]

2. Description of the Related Art Tractors, particularly agricultural tractors, can be roughly classified into wheel type (wheel type and track type (crawler type)). It can be subdivided into wheel drive type, front wheel drive type, etc., and the crawler type can be subdivided into full crawler type and semi crawler type (see pages 257 to 259 of the new edition agricultural machinery handbook).

[0003] A wheel-type tractor is equipped with a three-point link, a PTO shaft, a hydraulic control device, and the like, so that the tilling,
It can be used in a wide range such as sowing, medium tillage, weeding, harvesting, transporting, etc. It is used as a powerhouse for each work regardless of the season and is the mainstream of agricultural mechanization. In addition, full-crawler tractors have a smaller ground contact pressure than wheel-type tractors because they have a larger ground contact area, and can travel on uneven terrain such as soft terrain. For example, a so-called season-limited type dedicated machine exclusively used for agricultural land development and land improvement by a subsoiler or the like for securing drainage in wet fields or the like where a wheel-type tractor cannot work.

On the other hand, a semi-crawler type tractor is an auxiliary device for a wheel type tractor in which a crawler belt unit is mounted in place of a rear wheel, and has an intermediate performance between a wheel type and a full crawler type on a soft ground.

[0005]

The wheel-type tractor has high mobility and is suitable for a wide range of work. However, due to irregular weather in the autumn and the influence of snow in the early spring, etc., the tilling period (spring cultivation, crop growing, If harvesting is taken into account, the season will be almost a fixed period in spring.) If the field does not dry, it becomes virtually impossible for the wheeled tractor to enter the field, making it impossible to till. Was.

On the other hand, the full-crawler type tractor is effective in the above-mentioned situation, that is, under adverse conditions and in strong wetlands in various places, but lacks mobility and is a special purpose machine. It can be applied only to work, and if it is used for harvesting work in dry fields etc., it will excessively ruin the field, and eventually it will be necessary to prepare both wheel type tractors and full crawler type tractors, which is a problem in agricultural management. There is a problem that the investment in will be enormous.

For this reason, the present applicant discloses in Japanese Patent Application Laid-Open No. H10-45060, "a transmission and rear wheels provided with left and right front wheels steerable by operating a steering wheel and incorporated in a tractor body. Left and right rear wheels and left and right semi-crawlers are interchangeably provided on left and right rear axles driven by a rear wheel traveling transmission system having a differential device, and the left and right semi-crawlers are attached to the rear axle. The track frame includes a front and rear road follower mounted on a track frame, and an endless revolving body mounted on the rotary drive and the front and rear rotary follower. A tractor characterized by being supported by a tractor body so as to be swingable in a vertical direction via a support shaft (1 of a conventional example).

However, in the tractor traveling apparatus of the first conventional example, if all-wheel drive type (type in which both left and right front wheels and left and right semi-crawlers are driven) is adopted,
Since the driving force of the left and right semi-crawler is larger than the driving force of the front wheels, there is a problem that it is difficult to make full use of the front wheel driving force in wetland performance, as the balance of front and rear driving is easily disturbed and the front wheel is lifted up. Was.

In view of the above, the present invention provides a full drive type traveling apparatus in which the front left and right front wheels are constituted by rubber tires having lugs on their tread portions and the rear left and right semi crawlers are constituted by rubber crawlers. It is an object of the present invention to make the most of the driving force and to balance the driving force before and after, so that the wet field performance can be improved with less front rise.

[0010]

SUMMARY OF THE INVENTION The present invention is directed to a tractor comprising a full-drive traveling apparatus including front left and right front wheels and rear left and right semi-crawlers. The invention takes the following technical measures. That is, the tractor according to the present invention according to claim 1 is characterized in that the left and right front wheels are formed of rubber tires having lugs on a tread portion, and the left and right semi crawlers are formed of rubber crawlers.

By adopting such a configuration,
The driven front wheels rarely slip, making full use of their driving power and balancing with the driving power of the left and right semi-crawlers, that is, the driving power before and after is balanced, and the wet front performance is improved with less front climb It was done. In the present invention, it is preferable that the rubber tire is a pneumatic high lag tire (Claim 2). Further, the left and right semi-crawlers are provided on a track frame thereof with a plurality of rolls at intervals in a longitudinal direction thereof. Preferably, a wheel is provided, and a supporting shaft of the wheel is fitted in a support portion formed as a lower opening at the lower edge of the track frame (claim 3).

By adopting the structure according to the third aspect, the plurality of rolling wheels are assembled by fitting the support shafts to the support portion from below and fixing the support shaft ends to both sides with nuts. , Disassembly and the like became easier.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a tractor according to the present invention, in particular, an all-drive traveling apparatus will be described below with reference to the drawings. 1 (1) and 1 (2), an all-drive traveling device (which drives the front wheels 2 and the semi-crawler 3) is constituted by the front left and right front wheels 2 and the rear left and right semi-crawlers 3. FIG. 2 shows a side view and a rear view of the tractor 1.

The tractor 1 can be mounted with a work implement 5 shown as a rotary tilling device in the figure so as to be movable up and down via a link mounting means provided on the rear side, for example, a three-point link 4. The tractor 1 has a mounted engine 6 covered by a bonnet 7 and a driving and steering device comprising a steering wheel 8A and a seat 8B at the front and rear is surrounded by a cabin 9; The tractor may be provided with a safety frame that does not include the above-described safety frame.

The left and right front wheels 2 are driving wheels,
Steering wheels that can be steered by operating the steering handle 8A, and can be driven in the forward and backward directions by a power from the front wheel propulsion shaft device 10 via a front wheel differential, a deceleration / deceleration device, etc., not shown. . Left and right semi crawler 3
Is provided with a rotary drive body 12 attached to a rear axle 11 and front and rear rotary followers 14 and 15 mounted on a track frame 13 shown in FIG. The rotary driver 12 and front and rear rotary followers 14 and 15
And the endless revolving body 16 mounted on the
As shown in FIG. 1 (1), it has a substantially tapered shape.

The endless revolving body 16 in each of the left and right semi-crawlers 3 is formed of a rubber crawler (elastic crawler belt). In (1), lugs 16A in the shape of a horizontal single character, figure eight, etc. are bulged at intervals in the longitudinal direction of the band, so that a large traction force can be secured. 1 (1) based on a vertical line VV passing through the axis of the rear wheel 11.
As shown by, the front and rear contact lengths L1 and L2 are different. In FIG. 1 (1), the front contact length L1 is large and the rear contact length L2 is small. It is prevented from greatly projecting rearward to facilitate mounting of a working machine (rotary, plow, subsoiler, broadcaster, etc.) via three-point link means provided at the rear of the tractor body 1A, and front and rear. Ensuring the weight balance and improving the turning steering (small turning performance) by lifting the work machine, and ensuring sufficient ground contact length when working with the work machine down, avoids skidding on slopes. Blocks and promises great traction.

The front left and right front wheels 2, which are both steering wheels and driving wheels, are lugs 2A arranged in a tread portion such as a horizontal one-letter shape or a C-shape, in particular, pneumatic rubber tires having high lugs. The driving force with the left and right semi-crawlers 3, that is, the balance of the front and rear driving force, is secured. Here, the floating of the front of the tractor is prevented and the driving force of the front wheel 2 is sufficiently increased. It has been put to good use.

Referring to FIG. 2 to FIG. 5, the semi-crawler 3
Are exemplified. The rotary driving body 12 in the left and right semi-crawlers 3 can adopt a drum type, a roller type, a sprocket type or the like, but in the illustrated example, it is a sprocket type which engages and disengages with an engagement hole formed at a longitudinal interval of the rubber track. As shown in FIG. 3, the rear axle 11 is attached to the shaft end flange 11A of the rear axle 11 by using a plurality of bolts or the like so as to match the axis of the rear axle 11.

The left and right rear axles 11 are mounted on the tractor body 1.
A is rotationally driven by a traveling type transmission device built in A. Specifically, it is rotationally driven under a shift via a rear differential device and its output shaft, a final reduction device, and the like, and a left and right independent brake device. Can be braked. The left and right rear axles 11 are rotatably supported by bearings, not shown, which are inserted into rear axle housings 17 protruding outward from the left and right side surfaces of the tractor body 1A. The track frames 13 of the left and right semi-crawlers 3 are mounted so as to be vertically swingable about a swing support shaft 18.

That is, as shown in FIGS. 2 and 3,
A support (track frame support) 19 is provided on the lower surface of the rear axle box 17, and the bolt fastener 2 disposed in front of and behind the box 17 is provided.
0, a bolt fastener 21 from the lower surface of the housing 17 and a bolt fastener 22 from the rear surface, and the support 19 is mounted on the bearing portion 23 of the swing support shaft 18 below the rear axle housing 17. The bearing portion 23 is provided with left and right support pieces 23.
A cylindrical body 23C is fixed between A and 23B. The swinging support shaft 18 is inserted through the cylindrical body 23C and is positioned by a stopper 23D. The cylindrical body 23C has a lower link check of a three-point link. A mounting piece 23E for the chain is formed integrally.

The prior art illustrated above (JP-A-10-450)
No. 60), when mounting the left and right semi-crawlers so as to be able to swing up and down, a mounting frame which is framed in a rectangular shape is attached to the lower surface of the tractor body, and a swing support shaft is provided on the left and right sides of the mounting frame. In this case, projections are formed on the lower surface of the tractor body, which lowers the clearance on the ground, which is disadvantageous at the time of ridge-crossing work. In addition, the number of parts is large and the cost is high, and the specification changes (replacement of rear wheels and semi-crawler). ) Is solved by adopting the configuration of the present embodiment.

Although Japanese Patent Application Laid-Open No. 10-45060 is directed to a so-called large tractor, there is little problem with the use of a mounting frame. It provokes the problem. The track frame 13 of the semi-crawler 3 is formed in an inverted groove shape in cross section as shown in FIG. 3, and the upper surface of the track frame 13 is provided with a rubber crawler tension adjusting means 24 with a left and right space. In addition, the rotary driving body 12 is located between the right and left tension adjusting means 24 so that the configuration is compact in the up and down direction. An approaching window 13A is formed.

Further, a mounting plate 25 for the swing support shaft 18 is fixed to the inside of the track frame 13, and a saddle-shaped front and rear reinforcement is provided between the mount plate 25 and the swing support shaft 18 in a side view. The plate 26 is fixed, and firmly supports the swing support shaft 18. The swing support shaft 18 thus supported is inserted from the outside to the inside of the bearing 23, and at the insertion end. Positioned by the stopper 23D, the mounting plate 2
A disk-shaped collar 27 having a dust seal is interposed between 5 and the cylindrical body 23C.

At the lower edge of the track frame 13, support portions 28 are formed as lower openings at intervals in the longitudinal direction of the frame, and the support portions 28 are provided at intervals in the longitudinal direction. The support shaft 30 of the rolling wheel 29 is fitted and positioned in the front-rear direction. By adopting such a configuration, assembling and disassembling of the rolling wheel 29 becomes easy, and the support portion 28 is formed by expanding the opening edge downward as shown in FIG. The support shaft 30 on which the cylindrical collar 30 of the shaft 30 is fitted is mounted so that the left and right sides thereof are fastened by fasteners 31 such as bolts and nuts so as not to come off unexpectedly.

The front rotating vertical moving body 14 and the rear rotating vertical moving body 15 have the same structure as the rolling wheel 29 in the support portion 28, the support shafts 14A and 15A, the fastener 31 and the like. The left and right semi-crawlers 3 perform a pitching operation that follows (follows) irregularities in a field or the like by swinging the track frame 13 vertically about the swing support shaft 18 as a fulcrum. However, the amount of vertical swing must be controlled within a certain range.

For this reason, in the embodiment shown in FIGS. 2 to 7, the swing amount restraining means 32 is provided on the front side of the swing support shaft 18. Although the means 32 will be described in detail below, the means 32 may be provided on the rear side or on both the front and rear sides. In FIG. 2 to FIG. 7, the swing amount restraining means 32 has a mounting plate 33 fixedly extended in front of the support 19 (may be both rearward and frontward, but will be described only in the front). A pair of front and rear L-shaped flanges 34 are bolted to the outer surface of the plate 33, and a roller body 35 that rotates around the front-rear direction axis (downward when rearward) is rotated between the pair of flanges 34. It is suspended.

On the other hand, from the track frame 13 side, an outer mounting plate 36 located on the outer surface of the roller body 35 is fixed upright, and an inner mounting plate 37 located on the inner surface of the roller body 35 is fastened with upper and lower bolts. The upper and lower stoppers 40, 41 of the roller body 35 are also fixedly connected by fasteners 38, 39, and these bolt fasteners 38, 39 also serve as distance collars.
Is exterior.

In FIG. 2 and FIG. 6, when the rotator 12 is rotated forward in the direction indicated by the arrow F and the rubber crawler 16 is circulating and the tractor is moving forward, the front ridge is encountered. The semi-crawler 3 is configured such that the roller body 35 is supported by an upper stopper 4 around a swing support shaft 28 located immediately below the rear axle 11.
The semi-crawler 3 swings upward until the roller body 35 abuts on the lower stopper 41 about the swing support shaft 18 when the front crevice is encountered. In this swinging, the left and right semi-crawlers 3 swing left and right independently to perform so-called torsional running. The roller body 35 is regulated by the inner and outer mounting plates 36 and 37 to prevent excessive twisting. In this case, stable running is possible regardless of the dry or wet fields even in the uneven fields.

It is to be noted that a slide body may be used instead of the roller body 35, and the range of the vertical swing amount can be adjusted by making the vertical positions of the vertical stoppers 40 and 41 adjustable. The front rotation follower 14, which is the slack side of the rubber crawler 16 when the rotation driving body 12 rotates in the F direction, can be adjusted in tension by a tension (tension) adjusting device 24. Reference numeral 24 denotes a rod body (piston) of the follower support member 42 which is slidably fitted into a cylindrical body 44 having a coil spring 43 therein, and which can be strongly adjusted by the screw feed amount of an adjusting tool 45 having a screw-feedable plate. It has been.

In the first embodiment shown in FIG.
Is formed to be long so that the strength can be finely adjusted. Even in this case, the cylindrical body 44 is divided into right and left, and the rotary driving body 12 is interposed therebetween, thereby making it compact vertically. In the second embodiment shown in FIG. 2, a tension adjusting device 24 is provided in the center of the track frame 13 in the left-right direction and at the front, and in any case, the front rotation follower 14 is provided.
The tension in the center of the rubber crawler in the width direction can be adjusted.

In the embodiment shown in FIGS. 6 and 7, the cross section of the rear axle box 17 is formed in a rectangular shape whose upper and lower surfaces are inclined. A mounting base 44 attached to the lower part of the support column 43 of the safety frame (including the cabin support column) is arranged, and the two are reinforced with each other by being bolted while being clamped between the upper and lower surfaces of the rear axle housing 17. The attachment power becomes stronger.

In FIGS. 6 and 7, parts and components common to those in FIGS. 2 and 3 are indicated by common reference numerals. Further, the tension adjusting means (device) 24 may be of a fluid pressure type instead of a spring type.

[0033]

As described above in detail, according to the present invention, the left and right front wheels are made of rubber tires with lugs, and the left and right semi-crawlers are made of rubber crawlers. A tractor with reduced turning radius and improved turning performance can be provided.

[Brief description of the drawings]

FIG. 1 shows a tractor according to the present invention, wherein (1) is a side view and (2) is a rear view.

FIG. 2 is an overall side view of the semi-crawler according to the first embodiment.

FIG. 3 is a rear view of a main part of FIG. 2;

FIG. 4 is a view as viewed in the direction of arrows AA in FIG. 5;

FIG. 5 is a plan view of the swing amount restraining means.

FIG. 6 is an overall side view of a semi-crawler according to a second embodiment.

FIG. 7 is a rear view of a main part of FIG. 6;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Tractor 2 Front wheel 2A lug 3 Semi crawler 16 Rubber crawler 16A lug

Continued on the front page (72) Inventor Katsushi Maruyama 64 Ishizukita-cho, Sakai-shi, Osaka, Japan Inside Kubota Sakai Plant (72) Inventor Mutsumi Kana 64-Ishizukita-cho, Sakai-shi, Osaka Inside Kubota Sakai Plant, Inc.

Claims (3)

[Claims] 1. A tractor comprising a full-drive traveling device comprising front left and right front wheels and a rear left and right semi-crawler, wherein the left and right front wheels are formed of rubber tires having lugs on a tread portion. Characterized in that the semi-crawler is constituted by a rubber crawler. 2. The tractor according to claim 1, wherein the rubber tire is a pneumatic high lag tire. 3. The left and right semi-crawlers are provided with a plurality of rolling wheels on a track frame thereof at intervals in a longitudinal direction thereof, and the support shafts of the rolling wheels are formed in a lower opening shape on a lower edge of the track frame. The tractor according to claim 1, wherein the tractor is fitted on the formed support portion.