GB2222755A - Mechanism for suspending spreading ramp - Google Patents

Abstract

Mechanism for suspending a long, lightweight material spreading ramp comprising at least: a fixed frame (3) constituted by two parallel posts (5, 7) connected by spacers (9, 11) said fixed frame (3) being equipped with a lifting jack (13); a spring (23), whereof one end is suspended on the free end (17) of rod (15) of said lifting jack (13) and whereof the other end is connected spreading ramp (25); a horizontal shock absorbing means (33) integral with the spreading ramp (25) and which directly or indirectly acts in association with the posts (5, 7) of said fixed frame (3). <IMAGE>

Description

MECHANISM FOR SUSPENDING A SPREADING RAMP FOR AGRICULTURAL PRODUCTS The present invention relates to a mechanism for suspending a spreading ramp for agricultural products.

particularly long, lightweight material ramps.

Such ramps can be directly mounted on a tractor or on some other vehicle, or can be mounted on a towed trailer or the like. The evolution of technology is in the sense of using ever longer ramps, which can have ranges exceeding 24 metres when this is made possible by the land conditions.

The advantage of a wide range ramp is that it obviously avoids an excessive number of passages of the applicator vehicle through crops. One of the disadvantages of wide range ramps is their weight and the need for large, cumbersome structures.

In the case of spraying ramps of the aforementioned type, present developments tend towards the use of lightweight materials such as aluminium and/or composite materials.

One of the problems to be solved in the case of using lightweight spreading ramps is to ensure an adequate suspension thereof, so as to obtain a good ramp stability.

Numerous mechanisms for suspending ramps for spreading agricultural products are known, but are not generally suitable for long, lightweight ramps and generally take advantage of the weight of the ramp to obtain a good stabilization and/or a desired inclination thereof.

The object of the present invention is to supply a mechanism for suspending wide range spreading ramps made from lightweight materials, which leads to a good ramp stability, in such a way that the ramp is kept in an essentially horizontal position and which essentially absorbs all the impacts and shocks due to ground surface irregularities.

According to the present invention the suspension mechanism comprises at least: a fixed frame integral with the agricultural vehicle carrying the spreading ramp, constituted by two substantially vertical posts extending in parallel spaced manner from one another and connected by spacers, said fixed frame being equipped with an essentially vertical lifting jack; a spring, whereof one end is suspended on the free end of the rod of said jack and whereof the other end is connected via an articulation to the said spreading ramp which is suspended thereon; a horizontal shock absorbing member integral with the spreading ramp and which acts directly or indirectly in association with the posts of said fixed frame.

As a result of the suspension mechanism according to the invention, in which the spreading ramp is suspended in a swinging manner on a spring, which is itself suspended at the end of a lifting jack rod and in which the swinging movements are absorbed by a horizontal shock absorbing means, the speading ramp is kept in an essentially horizontal position during the displacement of the agricultural vehicle supporting it and the impacts and/or shocks due to ground irregularities are substantially absorbed.

Advantageously, the spreading ramp is suspended on the spring in the axis of its centre of gravity. As a result of this advantageous arrangement, the ramp is kept essentially horizontal despite the left to right oscillations due to movements of the base of the argicultural vehicle moving over uneven ground.

The connecting spring located between the head of the jack and the actual ramp to a considerable extent absorbs the vertical jerks in order to protect the ramp and free it from the movements of the agricultural vehicle supporting it.

The shock absorbing means permits a rapid recentering with substantially no jerks of the ramp following oscillations of the frame integral with the agricultural vehicle.

According to a preferred embodiment of the invention, the horizontal shock absorbing means comprises a double shock absorber or two horizontally acting shock absorbers integral with the ramp and bearing on the fixed frame and preferably on the substantially vertical posts thereof.

Advantageously, said shock absorbers can be constituted by springs.

It should be noted that the arrangement of a spring between the jack head and the spreading ramp is particularly suitable for lightweight ramps, whereas it has been found that an e.g. oleopneumatic accumulator, possibly connected to the oil circuit of the lifting jack is too rigid.

According to a variant of the present invention, the suspension mechanism also has a jack, preferably a hydraulic jack connected to the spreading ramp and to a guide slide of the spring. By pulling laterally on said guide slide, this makes it possible to find the new centre of gravity and retain the full advantages of the suspension when the ramp is only spread out o:i one side.

The invention is described in greater detail hereinafter relative to the drawings, wherein show: Figure 1 a front view of the suspension mechanism according to the invention; and Figure 2 is a partial detail view.

In the drawings identical references designate identical or similar elements.

The suspension mechanism 1 for spreading ramps in accordance with the present invention has a fixed frame 3 integral with the not shown agricultural vehicle and which comprises two substantially vertical posts 5 and 7, which are essentially parallel and connected by spacers 9, 11.

Frame 3 is equipped with a per se known lifting jack 13.

The head 17 of rod 15 of said jack has a pivot pin 19 on which is suspended a spring, or preferably a sleeve 21, within which is fixed one end of a spring 23, whose other end is articulated on the spreading ramp 25. As shown, said spring is protected by a guide slide 27. The pivot pins of the two ends of spring 23 are designated 29 and 31 and are shown in the dismantled state.

In this way, the spreading ramp is suspended in double swinging manner. According to the invention, the shock absorbing means 33 is intended to limit and absorb without jerks the swinging movements of said ramp. Advantageously, said shock absorbing means 33 is constituted by two springs 35, 37 bearing on the spraying ramp and on each occasion on one of the posts 57 of the fixed frame 3. Springs 35, 37 can also be protected by sleeves and guide slides and can be equipped with abutment shoes 39. It is obvious that the shock absorbing means can be constituted by a member equivalent to a spring, such as e.g. a double acting shock absorber or two shock absorbers of per se known type.

The embodiment shown in figure 1 also includes a hydraulic jack 41 connected to slide 27 and to the spreading ramp 25. In the represented embodiment, the action point 43 of said jack 41 on said slide 27 is positioned laterally of the latter. In order to bring the action point to the centre of said slide 27, said action point is connected by a yoke 47 to an action point 45, which is opposite to the first action point and which is also integral with slide 27.

The suspension of the spreading ramp for agricultural products according to the invention permits a good stabilization of the long, lightweight ramp by freeing it from the movements of the agricultural vehicle supporting it and the shock absorbing means leads to a rapid recentering of the ramp through attempting to bring it into a substantially horizontal position.

Moreover, the arrangement of a complementary jack between the ramp and the guide slide of the suspension spring makes it possible to use a spreading ramp which is only partly spread out or extended.

It is obvious that the scope of the invention is not limited to the embodiment described herein and instead also extends to the claimed scope.

Claims (8)

1. Mechanism (1) for suspending a spreading ramp for agricultural products, particularly a long, lightweight material ramp, comprising at least: a fixed frame (3) integral with the agricultural vehicle carrying the spreading ramp, constituted by two substantially vertical posts (5, 7) extending in parallel spaced manner from one another and connected by spacers (9, 11), said fixed frame (3) being equipped with an essentially vertical lifting jack (13); A spring (23), whereof one end is suspended on the free end (17) of the rod (15) of said jack (13) and whereof the other end is connected via an articulation (31) to the said spreading ramp (25) which is suspended thereon; a horizontal shock absorbing member (33) integral with the spreading ramp (25) and which acts directly or indirectly in association with the posts (5, 7) of said fixed frame (3).

2. Mechanism for suspending a spreading ramp for agricultural products according to claim 1, characterised in that the horizontal shock absorbing means (33) comprises a double shock absorber or two shock absorbers with a horizontal action integral with said ramp (25) and bearing on said fixed frame (3), preferably on the posts (5, 7) thereof.

3. Mechanism for suspending a spreading ramp for agricultural products according to claim 2, characterised in that the shock absorber or absorbers comprise one or two springs (35, 37) optionally located in sleeves and guide slides.

4. Mechanism for suspending a spreading ramp for agricultural products according to any one of the claims 1 to 3, characterised in that the spring (23) is located in a sleeve (21) and guide slide (27).

5. Mechanism for suspending a spreading ramp for agricultural products according to any one of the claims t to 3, characterised in that the ramp (25) is suspended on spring (23) in the axis of its centre of gravity.

6. Mechanism for suspending the spreading ramp according to any one of the claims 1 to 5, characterised in that it also comprises a jack (41), preferably a hydraulic jack, connected to the spreading ramp (25) and to a guide slide (27) of spring (23).

7. Mechanism for suspending the spreading ramp according to claim 6, characterised in that the action point (43) of jack (41) on slide (27) is located laterally of the latter and is connected by a yoke (47) to an opposite action point (45), which is also integral with slide (27).

8. Mechanism as described hereinbefore and as shown in the drawings.