HU186732B - Vibration-damped cat for self-propelled implements - Google Patents

Abstract

A damped mounting for a tractor cab has the whole cab(1) suspended by vertical struts (3) at each corner, with the ends of the struts fitted with universal joints or elastic couplings. Angled uprights (4) from the chassis serve as the upper support ends for the struts. The cab is damped by horizontal dampers between the cab base and the chassis, with the dampers set at different directions. The suspender struts are at least one metre long to reduce the resonant frequency of the suspension.

Description

BACKGROUND OF THE INVENTION The present invention relates to a cab with a reduced pitch for self-propelled machines or a driver's seat within the cab which is movable and damped in the horizontal plane relative to the vehicle body. self-propelled agricultural and construction machinery, tractors and off-road and agricultural trucks.

Solutions are known, e.g. sprung seats and sprung cabs that reduce driver exposure to vertical oscillations and vibrations.

However, the oscillations in the driving direction and in the transverse direction are not eliminated, although in many applications they are of the same magnitude as the vertical oscillations.

They recommend equipment for tractors that have a spring-loaded driver's seat that can be moved in three planes of space, and around the vehicle's longitudinal and transverse axes, with passive elements such as springs and dampers assigned to all these movements.

However, the disadvantage here is that the selected motion guidance creates unstable conditions by means of vertically movable supports for the horizontal components, and the complex design required by all the movement possibilities, and finally the center of gravity control required by the concept acted against the damping.

Finally, there are devices for lorries where the driver's cab is suspended in both vertical and horizontal directions relative to the chassis, while the suspension technique is disengaged using a Ό-shaped handlebar. Horizontal motion is guided by the spherical heads on this handlebar, which are guided in right-angled bushings and held in place by screw springs. The disadvantage of this design is that high frictional forces occur, resulting in strong wear, and difficulty in matching this system to low frequencies.

It is an object of the present invention to provide a simple, robust, low-wear device capable of significantly reducing driver stress due to oscillations in the horizontal plane.

It is an object of the present invention to provide a cab or driver's seat that simply reduces the impact of horizontal oscillations on the driver while reducing vertical oscillations in a known manner, such as with a suitably sprung driver's seat.

A shortcoming of the known applications in the above-mentioned applications is that in one case, vertical, movable, short-length supports were used for horizontal movement. In another case, the support of the cab weight on the special guide element required to do so adversely affected the suspension and damping properties. In particular, long spring paths, low self-frequencies, and low wear are difficult to achieve.

According to the present invention, the object is achieved by hinging the cab or driver's seat to the bars of the same length that are suspended vertically at the corners of the base plate or floor, thereby producing a pendulum-like structure; compensatory force, "which can then be reinforced by additional springs. The damping is done by paired hydraulic dampers, which are perpendicular to each other. The lengths of the vertically spaced bars are preferably at least 1 meter, but more preferably, to provide a sufficiently low frequency for the system.

The invention will now be further exemplified. Embodiments of the invention will be described in greater detail by means of the following drawings, of which:

Figure 1 is a schematic side view of a cab suspension for a particular type of combine harvester;

Figure 2 is a top plan view of the position of the hydraulic dampers on the base of the cab.

Turning to the figures, the cab 1 is secured to a vertically suspended rod 3 at the corners of the cab floor 2. The rods 3 are connected by means of ball joints 5 above to the load bearing body parts 4 of the forage harvester. The rods 3 are made of spring material and thus, because they are fixed to the cab 2 by means of a fixed clamp 6, an additional return force is created when the cab 1 swings. By hanging the driver's cab on rods 3 of at least 1 meter in length, it is possible, on the one hand, to move the cab 1 freely in the horizontal plane and, on the other hand, to rotate it about its vertical axis. Hydraulic dampers 7 are arranged symmetrically and in pairs with respect to the center of gravity of the cab 1, while transverse movements are provided by two hydraulic dampers 8, which are also arranged in pairs. Preferably, these pair-wise parallel hydraulic shock absorbers 7, 8 are mounted symmetrically with respect to the center of gravity of the cab 1 so that their lines of action are spaced at a maximum structural distance from the center of gravity so as to counteract the vertical axis of the cab 1; opposite.

Λ The characteristic curves of the 7, 8 hydraulic shock absorbers must be symmetrical in the pressure phase of the draw tube. This is ^; the easiest way to achieve this is to use hydraulic cylinders with a through-piston rod whose hydraulic connections are short-circuited. The damping coefficient of the hydraulic dampers 7.8 can be determined by means of a throttle integrated in the cross-section of the short-circuit. Preferably, hydraulic cylinders are used whose end positions provide braking so that a progressive damping curve can be achieved, eliminating the need to install elastic stops for swinging gaps.

Claims (4)

Patent claims 1. Reduced-swing cab for self-propelled machinery or a cab within the cab, movable and damped in a horizontal plane relative to the fuselage, characterized in that the bars (3) are provided vertically at each end (5) with fixed clamp (6) or spherical 21 at one end 186 732 are provided with a joint (5) and at the other end with a fixed clamp (6), and that when the fixed clamp (6) is used, the rods (3) are made of spring material! are. Reduced cab or driver's cab according to claim 1, characterized in that two pairs of parallel hydraulic dampers (7, 8) are arranged in such a way that one of the pairs of dampers (7) has the effect the other pair is perpendicular to the line of action of the shock absorber (8), and that the line of action of the pair is symmetrical with respect to the center of gravity of the cab (1) and is structurally permissible at a maximum distance therefrom. The reduced cab or driver's cab according to claim 2, characterized in that said hydraulic cylinders are provided with hydraulic piston rods (7, 8) having a through piston rod and providing end braking, the hydraulic connection 5 wires of which are short-circuited, a choke is inserted in its cross-section. 4. An embodiment of a reduced cab or driver's cab according to any one of claims 1 to 4, therewith 10 characterized in that additional springs are provided for increasing the return force of the driver's cab (1) or driver's seat, which are arranged in the same way as the hydraulic dampers (7, 8).