CH680807A5 - - Google Patents

Description

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CH 680 807 A5

2nd

description

The invention relates to a snow clearing vehicle with a clearing device arranged on the front and a sweeping roller arranged on the underside of the vehicle behind its front axle, and with a control device for adjusting or changing the roller speed.

Such a snow removal vehicle is known from German Patent 3,526,883. The roller circumferential speed is between a minimum value and a maximum value li-near-proportional! controlled to vehicle speed. This type of control ensures low energy consumption with reduced bristle wear when operating the roller brush. Practice has shown, however, that in sweeping operations with very tight bends, the sweeper roller is no longer able to remove the captured snow, since the snow removal vehicle drives particularly slowly due to the high steering angle, with the roller peripheral speed assuming the minimum value. In addition, as the steering angle increases, the angle of attack of the roller increases accordingly, so that the direction of conveyance of the roller moves more and more forward from the side.

In contrast, the present invention has for its object to ensure the functional use of the kehnwalze generally when driving slowly, especially when driving tight corners, without giving up the advantages of optimal use of energy and low bristle wear.

This object is achieved according to the invention in that when the vehicle is traveling slowly, namely when the vehicle is stationary, until a first vehicle speed (f-1) is reached, a high roller peripheral speed (w) can be set, which is close to or equal to a maximum roller peripheral speed (w-max) and that during normal travel, namely after exceeding the first vehicle speed (f-1) until reaching a second vehicle speed (f-2), the roller peripheral speed (w) between a minimum roller peripheral speed (w-min) and the maximum roller peripheral speed (w-max) , increasing with increasing vehicle speed (f), is adjustable.

According to this consideration, a distinction is made depending on the vehicle speed between a driving range with variable control of the roller circumferential speed after exceeding a first vehicle speed (f-1), the roller circumferential speed increasing with the vehicle speed, and a driving range below the first vehicle speed (f- 1), in which the roller peripheral speed is preferably controlled constantly at a value close to or equal to its maximum. This driving range is particularly important for clearing on tight bends, because here, due to the large angle of attack of the sweeping roller, the removal of snow from the vehicle area can only be managed by the high roller peripheral speed controlled according to the invention.

This reversal of the sweeping roller approximately to the maximum roller peripheral speed can be carried out in two ways within the scope of the invention; once, as already mentioned, depending on reaching or falling below the first vehicle speed (f-1), this is an extremely low speed, at around 5 km / h; on the other hand when the vehicle is cornering tightly, i.e. when a critical steering angle is reached or exceeded (L-1). The roller circumferential speed is then kept at a preferably constant value near or equal to the maximum roller circumferential speed until the first driving speed (f-1) is exceeded again or the critical steering angle (L-1) is undershot again, after which the driving speed-dependent variable control again the roller circumferential speed starts.

According to a particularly advantageous variant of the steering angle-dependent control, it is provided that after the critical steering angle (L-1) is exceeded, instead of a constant high roller peripheral speed, its value increases with the steering angle from the minimum roller peripheral speed (w-min) to the maximum roller peripheral speed (w-max). increases, expediently linear-proportional. Particularly effective, although less gentle on the bristles, would be a disproportionate increase in the circumferential roller speed.

In the context of the invention, it is expedient that the control device is programmable accordingly for the automatic determination and adjustment of the roller peripheral speed, i.e. control electronics are required which include at least the following input signal values:

a) Minimum roller circumferential speed (w-min);

b) maximum roller circumferential speed (w-max);

c) roller diameter (d) depending on roller size and / or wear;

d) respective vehicle speed (f);

e) first vehicle speed (f-1);

f) second vehicle speed (f-2);

g) critical steering angle (L-1).

It goes without saying that a course control for the circumferential roller speed (w) is required in the driving range between the first and the second vehicle speed, which is programmed, for example, according to a constant or variable ratio between the circumferential roller speed (w) and the vehicle speed (f). An example of a control characteristic of the roller circumferential speed as a function of the driving speed is explained in the above-mentioned German patent 3,526,883 on the basis of a diagram.

Within the scope of the invention there is the possibility of ramping up the circumferential speed of the

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speed when driving slowly or when cornering tightly through the control device, either as an alternative or to link both possibilities, preferably in such a way that the operating state of the sweeping roller is either dependent on reaching or exceeding the first driving speed (f-1) or from reaching or exceeding the critical steering angle (L-1). The steering angle signal can e.g. can be removed from the steering gear or on the handlebar using capacitive pulse generators. Via a relay of the control electronics, the travel voltage-dependent control voltage for the circumferential roller speed can then either be switched to a maximum value or increase proportionally to the steering angle signal.

For a snow-clearing vehicle controlled according to the proposed invention, the driver has the advantage that he can concentrate entirely on controlling the vehicle, especially when driving tight bends or maneuvering in a confined space, without having to fear a poorer clearing result. The control device automatically ensures that the appropriate broom speed is always set regardless of the driving conditions.

In the following an embodiment of the invention is explained with reference to the drawing. It shows

1 is a plan view of a snow removal vehicle,

Fig. 2 is a schematic plan view of the snow removal vehicle when cornering

Fig. 3 is a plan view of FIG. 2, in tight cornering.

Fig. 1 shows a top view of a snow removal vehicle as a truck, on which a snow plow (1) and a blow device (2) on the rear - which is not the subject of the invention but is only shown for the sake of completeness - are attached. A sweeper roller (3) is located between the vehicle axles on the underside of the vehicle. Both the sweeping roller (3) and the snow plow (1) are pivoted so that they can either clear the snow on both sides; in the case of FIG. 1, the snow is transported according to arrows P and K to the right side of the vehicle; the brush roller (3) brushes the snow against the direction of travel (arrow F), i.e. the brush roller (3) rotates in the opposite direction to the wheels of the vehicle. The snow, which is neither caught by the snow plow (1) nor by the sweeping roller (3), is blown out of the lane of the snow removal vehicle by the blower (2), also selectable to the right or left.

2 and 3 show such a snow removal vehicle - without a blowing device - in each case when cornering, the track circles of the outer and inner ends of the snow plow (1) and the sweeping roller (3) being shown. In addition, the track circle of the vehicle, in the case of FIG. 2 with 26 m and in the case of FIG. 3 with 13.8 m in diameter.

According to Fig. 2, i.e. with a track circle of 26 m for the vehicle shown in FIG. 1, the critical steering angle (L-1) has been reached; this just overlaps the inner track circles of the clearing device (1) and the sweeping roller (3), i.e. the sweeping track (5) is completely covered by the clearing track (4). According to FIG. 3, this coverage is no longer present. Here the greatest steering angle is reached with a vehicle's turning circle of 13.8 m.

In principle, the critical steering angle can be freely selected; it is preferred to set it in such a way that when it is reached a sufficient throwing distance of the sweeping roller is achieved. After the critical steering angle (L-1) has been exceeded, the reversal from the circumferential roller speed dependent on the driving speed to a high circumferential roller speed or with increasing steering angle is effected. For this purpose, the critical steering angle (L-1) must be given to the control electronics as an input signal.

When driving straight ahead, the angle of attack (A 1) between the sweeping roller and the direction of travel is approximately 45 °; it increases increasingly when cornering with a larger steering angle or steering angle, as a comparison with FIG. 2 (angle of attack A 2) and FIG. 3 (angle of attack A 3> A 2> A 1) shows. 3, the angle of attack (A 3) is already so large that a considerable part of the snow is thrown forward by the sweeper under the vehicle instead of to the side. The desired cleaning effect can only be achieved with a high brush speed.

A snow-clearing vehicle with the described properties can be used advantageously in particular as a high-performance vehicle for clearing runways on airfields. As a result of the increase or maximization of the sweeper speed as proposed according to the invention when driving slowly or when a critical steering angle is reached, the snow removal vehicle is also enormous, e.g. Can be used on runways or in the handling area of airfields. Due to the fact that the sweeping roller is operated at maximum speed on tight bends, it enables a sufficient throw distance, even under the condition that the sweeping track (5) is not covered by the clearing track (4), e.g. as shown in Fig. 3.

Claims (3)

Claims 1. Snow removal vehicle with a clearing device (1) arranged on the front and a sweeping roller (3) arranged on the underside of the vehicle behind its front axle, as well as with a control device for setting or changing the roller speed according to the following rules: a) When the vehicle is traveling slowly, namely when the vehicle is stationary until a first vehicle speed (f-1) is reached, a high roller peripheral speed (w) can be set, which is close to or equal to a maximum roller peripheral speed (w-max), b) in normal driving, namely after exceeding 5 10th 15 20th 25th 30th 35 40 45 50 55 60 65 5 CH 680 807 A5 the first vehicle speed (f-1) until a second vehicle speed (f-2) is reached, the roller peripheral speed (w) is between a minimum roller peripheral speed (w-min) and the maximum roller peripheral speed (w-max), with increasing vehicle speed (f) increasing, adjustable. 2. Snow clearing vehicle with a clearing device (1) arranged on the front and a sweeping roller (3) arranged on the underside of the vehicle behind its front axle, as well as with a control device for setting or changing the roller speed according to the following rules: a) When driving straight ahead and during normal cornering of the vehicle, namely until a critical steering angle (L-1) is reached, the roller peripheral speed (w) is between a minimum roller peripheral speed (w- min) and the maximum roller circumferential speed (w-max), increasing with increasing vehicle speed (f), adjustable; b) when the vehicle is cornering tightly, namely after the critical steering angle (L-1) has been exceeded, a high roller circumferential speed (w) can be set, which is close to or equal to the maximum roller circumferential speed (w-max). 3. Snow clearing vehicle with a clearing device (1) arranged on the front and a sweeping roller (3) arranged on the underside of the vehicle behind its front axle, as well as with a control device for setting or changing the roller speed according to the following rules: a) When driving straight ahead and with normal cornering of the vehicle, namely until a critical steering angle (L-1) is reached, the roller circumferential speed (w) is between a minimum roller circumferential speed (w-min) and the maximum roller circumferential speed (w -max), increasing with increasing vehicle speed (f), adjustable; b) when the vehicle is cornering tightly, namely after the critical steering angle (L-1) has been exceeded, a high roller circumferential speed (w) can be set, which increases with increasing steering angle from the minimum roller circumferential speed (w-min) to the maximum roller circumferential speed (w -max) increases. 4th