GB2165132A

GB2165132A - Lifting implements on tractors

Info

Publication number: GB2165132A
Application number: GB08524783A
Authority: GB
Inventors: Jean-Louis Chapuis
Original assignee: HEIDILAND SA
Current assignee: HEIDILAND SA
Priority date: 1984-10-09
Filing date: 1985-10-08
Publication date: 1986-04-09
Also published as: GB8524783D0; CH660831A5; DE3535824A1; FR2571206A1; FR2571206B1

Abstract

In order to facilitate the height regulation of the lifting apparatus of an agricultural implement 7 mounted on the front of a tractor there is provided a quadrangular chassis (1) equipped with rails (2) having equidistant holes. Twin carrying arms (4) linked to the lower portion of the chassis (1) are rendered rigid by a girder (5) which has, at its extremities, semi-automatic attachments (6, 8) for the agricultural implement (7). When the tractor is driven with the agricultural implement (7) lifted with the aid of the hydraulic jack (9), the lifting apparatus is retained by means of the safety shank (15). <IMAGE>

Description

SPECIFICATION Apparatus for lifting an implement mounted on the front of a tractor The present invention relates to a lifting apparatus for lifting an implement mounted on the front of a tractor.

In French patent specification No. 2311494 there is disclosed a three-point lifting system adapted for fixing on the front of a tractor, said lifting system comprising a main framework which is provided with a hydraulic cylinder lifting system and firmly secured to the chassis of a tractor by means of a fixing member and an adjusting member, the main frame-work, the lifting arms, the linking arms and the actuating member with the stop of the lifting system forming an adjustable quadrilateral.

German patent application 2718959 describes a support apparatus for an agricultural implement mounted on the front of a tractor and consisting of two lower guides which are equipped within their axis of pivot with forks which enclose bearings situated in the proximity of the tractor, each form bearing a pivot capable of being withdrawn from the corresponding bearing.

German patent application 275978 relates to a guided implement mounted on the front of a tractor. The upper guide bar and the lifting jack are mounted on a suspension trestle consisting of a single cast iron section and linked to the tractor by means of sidepieces fixed to the sides of the tractor. The two guide bars situated in the proximity of the tractor are mounted on a shaft disposed under the suspension trestle and capable of pivoting in bearings located in the sidepieces. The free extremities of the upper and lower guide bars are linked to one another by an iron strut.

German patent application 3216589 relates to an apparatus for lifting an implement mounted on the front of a tractor. A chassis fixed to the support of the shaft in front of the tractor is composed of lower arms in the form of knuckles, said arms being mounted in a pivoting manner and actuated by hydraulic jacks.

Patent application PCT/AT/00023 concerns an apparatus for fixing an implement to the front of a vehicle. This apparatus consists of a chassis disposed transversely in relation to the longitudinal axis of the vehicle, mounted on a main shaft, capable of pivoting about said shaft and having the implement at its free extremity. Hydraulic cylinders acting directly on the implement are provided in order to control the working position of the implement, either vertically or horizontally or in parallel or, moreover, transversely in relation to the longitudinal axis of the vehicle.

It is an object of the instant invention to provide a lifting apparatus capable of being fixed to the front of a tractor at an appropriate height, comprising fixed arms preventing any lateral flexion, preferably enabling rapid attachment of the implement and preferably also having a safety device for travelling with the raised implement.

This purpose is achieved with the apparatus according to the invention, and as defined in the claims.

The enclosed drawings illustrated as an example a form of embodiment of the apparatus according to the invention, in which: Figure 1 shows a lateral view of the apparatus having an implement mounted thereon, Figure 2 shows a plan view of Figure 1, without the implement, and Figure 3 shows a front view of the apparatus.

The lifting apparatus shown comprises a rigid quadrangular chassis 1, the vertical uprights 1c, Id of which are equipped with rails 2 having equidistant holes therein making it possible to fix the chassis 1 to the front of the tractor (not shown) at the desired height. Chassis 1 is composed of boxsection tubes welded together and constituting upper horizontal girder 1a, lower horizontal girder 1b and the vertical uprights 1c, 1d.

The lower girder 1b of the chassis 1 is equipped with pairs of brackets 3 in which the twin carrying arms 4 are able to pivot, the free extremities of which are welded onto a rigid box girder 5, preventing any buckling of the twin carrying arms 4 (Figure 2). The two extremities of the rigid girder 5 bear semi-automatic coupling means 6 capable of receiving an agricultural implement 7. The coupling means 6 are equipped with stop arms 8 mounted in a rotating manner around the pivots and in such a manner that they retain the position adopted under the effect of their own weight. In order to render these inoperable it is merely necessary to swing these aside (Figure 1).

The lower part of the central portion of the upper horizontal part 1a of chassis 1 bears a hydraulic jack 9 mounted pivotally on the lower part of the brackets 10, the piston rod 11 of said jack being linked, also pivotally, to the rigid girder 5 by the brackets 12.

The brackets 10 extend upwards on the front fact of the central portion of upper horizontal girder 1a and are provided with a pivot 13 around which there can oscillate a stay 14 of adjustable length and linked to the agricultural implement 7. On a protrusion of pivot 13 there is mounted, in a pivotal manner, a safety shank 15 which, when the agricultural implement 7 is lifted by means of the hydraulic jack 9, is retained on the rigid girder 5 by means of a lug 16 carried by a bracket 17 welded on the upper central portion of the latter (Figure 1).

The lifting apparatus described presents the following advantages: a) thanks to holes provided in the rails 2 it is possible to raise it to an appropriate height on the front portion of the tractor, b) the twin carrying arms 4 and the rigid girder 5 prevent any buckling, i.e. any lateral displacement of said carrying arms, c) the semi-automatic coupling means 6 with their stop arms 8 facilitate the rapid mounting and removal of the agricultural implement 7, d) the safety shank 15 and the lug 16 constitute a safety unit when the tractor is moved with the implement raised.

Claims

1. A hitch for locating an agricultural implement to the front of a tractor comprising a rigid frame having means for securing it to the tractor at a plurality of heights above the ground, two spaced apart arms pivotly mounted with respect to the frame and extending forwardly therefrom and joined at their outer ends by a rigid member adapted to receive the implement, and jacking means mounted between the frame and the rigid member.

2. Apparatus for lifting an implement mounted at the front of a tractor characterized in that it comprises a quadrangular chassis having vertical uprights carrying rails, said rails having holes therein at equidistant intervals, the forward facing part of the lower girder of the chassis being equipped with twin carrying arms mounted pivotally on brackets and reinforced at their outer free extremities by a rigid girder carrying at its free extremities semi-automatic coupling means equipped with stop arms adapted to receive the implement and wherein the central portion of the upper girder of the chassis has a hydraulic cylinder mounted pivotally in brackets and wherein the piston rod is connected by means of brackets to the lower central portion of the rigid girder the brackets of the central portion of the upper girder of the chassis being equipped with a pivot which serves to attach, on the one hand, a stay connected to the implement and, on the other hand, a safety shank which, when the tractor travels with the implement in the raised position, is connected to a lug of the rigid girder.

3. Lifting apparatus as claimed in claim 2, characterised in that the chassis and the rigid girder are box girders.

4. Lifting apparatus as claimed in claim 3, characterised in that the stop arms pivot around the pivots and are mounted in a manner such that they remain in their operating positions under the action of their own weight.

5. A hitch for locating an agricultural implement on the front of a tractor substantially as described herein with reference to and as shown in the accompanying drawings.