DK143913B - SHOCK ABSORBER - Google Patents

Description

1 143913

The invention relates to a shock absorber of the kind specified in the preamble of the claim. In such a shock absorber, the end cap can be applied by a purely axial movement, which is particularly advantageous when the shock absorber is of the kind filled with a highly compressed gas type.

Swedish Patent Specification No. 359 628 discloses a linear hydraulic servomotor in the form of a cylinder with a piston, the piston rod of which passes through one end cover which is held in the end portion of the cylinder by means of a locking ring which is located in two opposite one another. notes in the cylinder wall and cover, respectively, 'For sealing the connection between the two parts, there is an O-ring located in a groove in the cover.

This known construction does not guarantee an effective seal which can withstand the high pressures that can occur in a shock absorber with highly compressed gas.

English patent specification 1 055 324 discloses a similar cylinder, however, the end cap, like the present invention, has a flange extending beyond the end surface of the cylinder. The cover carries an inner ring 20 which can be tightened by means of screws to a shoulder on the cover and by wedge action between two inclined faces of the ring and the cover can push a spring ring with corresponding inclined faces towards the bottom of a groove in the cylinder surface. . Also, this cylinder has only one sealing ring 25 for sealing between cover and cylinder.

The invention has for its object to provide a shock absorber of the kind in question which makes it possible to provide a certain desired abutment pressure between the elastic sealing ring, the end cover and the cylinder and which is furthermore easy to assemble.

This object is achieved by the shock absorber being designed as specified in the characterizing part of the claim. The tapered surface of the end portion of the cylinder not only acts as the abutment surface of the sealing ring, but also serves to guide the spring ring into the cylinder during cover insertion. The inclined abutment surface causes the ratio between a given axial movement of the cover relative to the cylinder and the consequent change in the abutment pressure of the sealing ring to be greater than it would be if the sealing ring was disposed between surfaces which are standing. perpendicular to the cylinder axis. This allows a more precise adjustment of the system pressure.

Part of an embodiment of the shock absorber according to the invention is shown in axial section in the drawing and will be described in more detail below with reference thereto.

In the drawing, 1 is a cylinder with an end cap 2 through which a piston rod 3 passes. A sealing ring 4 establishes a seal between the piston rod 3 and the cover 2. This cover has a flange 5, and the cylinder 1 is formed at the end surface 7 with a tapered surface 8.

In a recess 6 below the flange 5, a sealing ring 15 9 is placed which abuts the conical surface 8. The cover 2 is furthermore formed with an annular groove 10, and the cylinder 1 has an annular groove 11, which is limited downwards by a conical wall portion 12 to facilitate the insertion of the end cover 2 into the cylinder 1. In the two grooves 10 and 11 lies a spring ring 13.

Attaching the end cover 2 to the cylinder. 1 is as follows:

The end cover 2 is provided with the sealing ring 9 and the spring ring 13 having a larger diameter than the groove 11 in the cylinder 1.

The end cover 2 is inserted into the cylinder 1, whereby the spring ring 13 is pressed into the groove 10 by means of the conical surface 8. The sealing ring 9 is compressed before the end cover 2 reaches its end position. The sealing ring 9 has a very limited opportunity to move between the flange 5 and the cylinder end surface 7. The spring ring 13 springs into the groove 11 when the grooves 10 and 11 are aligned.

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