CZ288674B6 - Tractor intended particularly for use in agriculture and forestry - Google Patents

Abstract

The present invention relates to a tractor intended particularly for use in agriculture and forestry in which a driving set (30) formed by an internal combustion engine (31) and a transmission gear is mounted on a supporting structure (10) that is arranged as a unit-built backbone frame (11) in which there are incorporated at least three final drive housings (12) with independently spring-loaded swing axles (13) from which the first and the last are steerable. On the middle swing axle (13) the springing elements (20) are supplemented with a thrust controller (21). A reinforcing frame (14) is attached to the unit-built backbone frame (11). The driving set (30) is formed by combination of mechanical and hydraulic gearing units.

Description

Tractor, especially for agricultural and forestry work

Technical field

BACKGROUND OF THE INVENTION The present invention relates to a tractor intended primarily for agricultural and forestry work, in which a drive unit consisting of an internal combustion engine and a transmission is mounted on a supporting structure.

BACKGROUND OF THE INVENTION

The tractor is one of the main mobile energy resources in agriculture and forestry. At present, two-axle wheeled tractors with wheel drive of one or both axles prevail. The overall efficiency of the energy transmission of the engine to the traction elements ranges from 50 to »

%. The most important part of the total power transmission losses by the drive wheels are slip losses, not only by the deformation of the soil but also by the tangent deformation of the tires. The maximum power of conventional tractors with a rigid front axle and a fixed engine, transmission and axle block has stabilized at 200 kW. The technical design of these tractors does not make it possible to increase the working and travel speed without adversely affecting the operator. The tensile force is limited by the size of the tires on the front and rear axles. Various modifications are used to increase power transmission, such as dual tire mounting, half-track adaptations or articulated drive arrangements, which result in an increase in the tractor's footprint with negative operating consequences.

SUMMARY OF THE INVENTION

The aforementioned drawbacks are largely eliminated by the agricultural and forestry tractor, in which the propulsion unit consisting of an internal combustion engine and a transmission is mounted on a supporting structure. Its essence is that the load-bearing structure is configured as a modular backbone frame in which at least three distribution boxes with independently spring-loaded pivoting half-axles are incorporated, the first and last of which are steerable. On at least one half-axle pair, the spring elements may be supplemented by a pressure force regulator. A reinforcing frame can be attached to the modular backbone frame to accommodate auxiliary exploitation and special equipment. The drive unit may be a combination of mechanical and hydraulic gears.

The arrangement of a tractor with a modular backbone frame according to the invention makes it possible to place three axles with 34 "tires on the ground plan of commonly used tractors. The three-axle chassis modification allows the tractor to increase its weight and significantly increase its tractive effort. The independent suspension of all the wheels makes it possible to increase the average speed of the tractor and make it easier to overcome off-road irregularities with sufficient operator comfort and eliminate the risk of spinal injuries. A pair of steerable axles make it possible to reduce the tractor's turning radius. The summary of the above characteristics of the tractor according to the invention greatly reduces unproductive times and increases all-day performance compared to conventional tractors. An indispensable advantage is the low soil compaction, which is associated with lower soil resistance during further processing.

Overview of the drawings

An exemplary embodiment of a tractor according to the invention is schematically shown in the accompanying drawings. FIG. 1 shows a side view of the tractor with a partial longitudinal section; FIG.

Fig. 3 is a front view with a cross-section in front of the central axle; Fig. 3 is a plan view and Fig. 4 is a plan view of the tractor when rotating.

-1 CZ 288674 B6

DETAILED DESCRIPTION OF THE INVENTION

The agricultural and forestry tractor according to the invention consists of a propulsion unit 30 consisting of an internal combustion engine 31 and a transmission 32 and mounted on a supporting structure 10. 5 The supporting structure 10 is arranged as a modular backbone frame 11 in which three timing gears are incorporated. The first and last pair of spring-loaded pivoting half-axles 13 are steerable. A spring element 20 is provided on the middle pair of spring-loaded pivoting half-axles 13, which is supplemented by a pressure force regulator 21. A reinforcing frame 14 is attached to the modular backbone frame 11 for accommodating auxiliary exploitation and special devices 33.

The modular backbone 11, together with the gearboxes 12 and the independently suspended swinging half-axles 13 and the stiffening frame 14, form a compact chassis on which three pairs of tires up to 34 ”can be placed, making full use of the tractor's weight. 15 Independently suspended and swiveling half-axles 13 ensure constant contact between the tires and the support, even when driving on rough terrain. The pressure of the individual half-axles 13 can be adjusted according to the terrain and operating conditions by the pressure force regulator 21. The tractor can be equipped with a number of auxiliary exploitation and special devices 33, eg lifting mechanisms, suspension devices, blade, power take-offs, but also a driver's cab, which are fastened by the fastening elements 20 to the modular spine frame 11 and to the reinforcement frame 14. The tractor power unit may be a combination of mechanical and hydraulic transmissions. The tractor's three-axle chassis makes it possible to meet the limit load of individual wheels and the overall transport width. A pair of steerable axles greatly reduces the turning radius of the tractor.

The tractor according to the invention is primarily intended for agricultural and forestry work and can also be used in conventional transport.

Claims (4)

PATENT CLAIMS 1. A tractor, in particular for agricultural and forestry work, in which the drive unit is formed 35, characterized in that the support structure (10) is arranged as a modular backbone frame (11), in which at least three distribution boxes (12) with independently spring-pivoted half-axles (13) are incorporated. of which the first and last are controllable. 40 Tractor according to claim 1, characterized in that the spring elements (20) are supplemented by a pressure force regulator (21) in at least one pair of spring-loaded pivoting half-axles (13). Tractor according to claim 1, characterized in that a reinforcing frame (14) is attached to the modular backbone frame (11) for accommodating auxiliary exploitation and special devices (33). Tractor according to claim 1, characterized in that the drive unit (30) is a combination of mechanical and hydraulic transmissions.