GB2123522A

GB2123522A - A Gas spring or strut

Info

Publication number: GB2123522A
Application number: GB08318302A
Authority: GB
Inventors: Christian Grabner; Volker Nickel
Original assignee: Daimler Benz AG
Current assignee: Daimler Benz AG
Priority date: 1982-07-10
Filing date: 1983-07-06
Publication date: 1984-02-01
Also published as: FR2529980A1; DE3225974A1; GB8318302D0

Abstract

A gas spring 1, in particular for engine bonnets and/or boot lids of motor vehicles, consists of a cylinder 2 filled with gas under pressure and a piston 4 which can be displaced within it and which is connected to a piston rod 3. In order to make possible a greater extension of the gas spring 1 which exceeds the normal operating path, provision is made for a covering tube 5, open at one end, to be placed over the cylinder 2 so as to be telescopically displaceable relative to it. The other end of the covering tube 5 may have an anchorage member 6 and a buffer 7 may be provided on the end of the cylinder 2 inside the tube 5. This arrangement enables the bonnet or boot lid to be opened 90 DEG when necessary, although in normal use the spring moves it through 45 DEG . <IMAGE>

Description

SPECIFICATION A gas spring or strut The invention concerns a gas spring or strut, particularly but not exclusively for engine bonnets and/or tail gates or boot lids of motor vehicles, which consist of a cylinder filled with gas under pressure and a piston displaceable within it and connected to a piston rod.

Such gas springs or struts are often used to assist the opening movement of, for example, an engine bonnet of a motor vehicle. Their extension length is then so dimensioned that an opening angle of the bonnet of, for example, approximately 450, which permits normal maintenance work in the engine space, is obtained. In various vehicle types, however, there is an additional requirement that an opening angle of 900 must be attained, perhaps during the final assembly of the vehicle or later when changing the internal combustion engine. For this purpose, it was previously necessary to release at least one of the retaining points of the gas spring.

The present invention seeks to provide a gas spring or strut of the previously described type is that such an enlarged opening angle is also possible without releasing the gas spring or strut linkage.

According to the invention there is provided a gas spring or strut comprising a cylinder filled with gas under pressure and a piston displaceable within said cylinder and connected to a piston rod, wherein a covering tube, open at one end and subjected internally to atmospheric pressure, is placed over the cylinder and is telescopically displaceable relative to it.

In one embodiment of the invention, the cylinder and the outer covering tube are of approximately the same length, the tube being guided on the external wall of the cylinder and in another embodiment of the invention, the covering tube is provided at one end with a retaining means, such as an eye.

An embodiment of the invention is now described in more detail below by way of example and with reference to the accompanying drawings, in which: Figure 1 shows a longitudinal section through a gas spring, or strut, according to the invention, in the retracted or compressed position, Figure 2 shows a section corresponding to Figure 1 with the gas spring or strut fully extended, Figure 3 shows the arrangement of such a gas spring or strut on an engine bonnet of a motor vehicle with an opening angle of approximately 450, and Figure 4 shows the arrangement according to Figure 3 with an opening angle of 900.

The gas spring or strut 1 shown in the drawing has a cylinder 2, in which a piston 4 connected to a piston rod 3 is displaceably located. A covering tube 5 is pushed telescopically over the cylinder 2, this covering tube having a retaining eye 6 on one end face. An elastic buffer 7 is provided on an end face of the cylinder 2 inside the covering tube 5.

With this arrangement, the covering tube can, in a manner which is not shown, be secured against complete withdrawal of the cylinder.

Figures 3 and 4 of the drawing show diagrammatically an engine bonnet 8 of a motor vehicle, not shown in greater detail, which is articulated by means of levers 9, 10 to an integral part 11 of the vehicle. The gas spring or strut 1, which permits the engine bonnet 8 to be opened as far as the 900 position shown in Figure 4, is also pivotally connected to the engine bonnet 8 and the integral part 11 of the vehicle. Means (not illustrated) can be provided to retain the bonnet 8 in its fully open position as shown in Figure 4, with the gas spring or strut in its fully lengthened condition, corresponding to Figure 2 of the accompanying drawings.

1. A gas spring or strut, comprising a cylinder filled with gas under pressure and a piston displaceable within said cylinder and connected to a piston rod, wherein a covering tube open at one end and subjected internally to atmospheric pressure, is placed over the cylinder and is telescopically displaceable relative to it.

2. A gas spring or strut according to Claim 1, wherein the cylinder and the covering tube have approximately the same length and the covering tube is guided on the external wall of the cylinder.

3. A gas spring or strut according to Claim 1 or Claim 2 wherein the covering tube has a retaining means or a similar member on one end face.

4. A gas spring or strut substantially as hereinbefore described with reference to the accompanying drawings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION A gas spring or strut The invention concerns a gas spring or strut, particularly but not exclusively for engine bonnets and/or tail gates or boot lids of motor vehicles, which consist of a cylinder filled with gas under pressure and a piston displaceable within it and connected to a piston rod. Such gas springs or struts are often used to assist the opening movement of, for example, an engine bonnet of a motor vehicle. Their extension length is then so dimensioned that an opening angle of the bonnet of, for example, approximately 450, which permits normal maintenance work in the engine space, is obtained. In various vehicle types, however, there is an additional requirement that an opening angle of 900 must be attained, perhaps during the final assembly of the vehicle or later when changing the internal combustion engine. For this purpose, it was previously necessary to release at least one of the retaining points of the gas spring. The present invention seeks to provide a gas spring or strut of the previously described type is that such an enlarged opening angle is also possible without releasing the gas spring or strut linkage. According to the invention there is provided a gas spring or strut comprising a cylinder filled with gas under pressure and a piston displaceable within said cylinder and connected to a piston rod, wherein a covering tube, open at one end and subjected internally to atmospheric pressure, is placed over the cylinder and is telescopically displaceable relative to it. In one embodiment of the invention, the cylinder and the outer covering tube are of approximately the same length, the tube being guided on the external wall of the cylinder and in another embodiment of the invention, the covering tube is provided at one end with a retaining means, such as an eye. An embodiment of the invention is now described in more detail below by way of example and with reference to the accompanying drawings, in which: Figure 1 shows a longitudinal section through a gas spring, or strut, according to the invention, in the retracted or compressed position, Figure 2 shows a section corresponding to Figure 1 with the gas spring or strut fully extended, Figure 3 shows the arrangement of such a gas spring or strut on an engine bonnet of a motor vehicle with an opening angle of approximately 450, and Figure 4 shows the arrangement according to Figure 3 with an opening angle of 900. The gas spring or strut 1 shown in the drawing has a cylinder 2, in which a piston 4 connected to a piston rod 3 is displaceably located. A covering tube 5 is pushed telescopically over the cylinder 2, this covering tube having a retaining eye 6 on one end face. An elastic buffer 7 is provided on an end face of the cylinder 2 inside the covering tube 5. With this arrangement, the covering tube can, in a manner which is not shown, be secured against complete withdrawal of the cylinder. Figures 3 and 4 of the drawing show diagrammatically an engine bonnet 8 of a motor vehicle, not shown in greater detail, which is articulated by means of levers 9, 10 to an integral part 11 of the vehicle. The gas spring or strut 1, which permits the engine bonnet 8 to be opened as far as the 900 position shown in Figure 4, is also pivotally connected to the engine bonnet 8 and the integral part 11 of the vehicle. Means (not illustrated) can be provided to retain the bonnet 8 in its fully open position as shown in Figure 4, with the gas spring or strut in its fully lengthened condition, corresponding to Figure 2 of the accompanying drawings. CLAIMS