DE2159521A1 - Diaphragm for pneumatic control and regulating devices - Google Patents

Description

PATENT LAWYERS Dipl.-Ing. WERNER COHAUSZ Dipl.-Ing. WILHELM FLORACK. DipUng. RUDOLF KNAUF

4 Düsseldorf, Schumannstrasse 97

C.A.V. Limited November 29, I97I

Well Street
Birmingham / England

Diaphragm for pneumatic control and regulating devices

The invention relates to a membrane for pneumatic control and regulating devices, such as those used in internal combustion engines be used.

In known devices of this type, the membrane is annular and consists of a pair of animal or synthetic Skins with the flat sides facing each other. The skins are attached at their edge to a housing and also to one mounted in the housing movable member provided with a pair of discs between which the skins are clamped.

Despite the fact that the skins have been treated with various impregnations to reduce the porosity while maintaining the Flexibility still occurs "a leak of air through the skins, causing the control or regulating device to operate is adversely affected, especially when the difference in pressures on both sides of the membrane is small.

The object of the invention is to provide a membrane in which the leakage of air is reduced to a minimum.

25 377 - 2 -

U / Be

209825/0769

According to the invention this object is achieved by a membrane which consists of a pair of animal or synthetic skins, which are arranged with their flat sides to each other and between them there is a layer of a high-density plastic that is flexible and does not significantly increase the stiffness of the membrane.

An embodiment of a pneumatic control or regulating device, which includes a membrane according to the invention will be described with reference to the accompanying drawing, which is a side view shows in section through part of the membrane.

The membrane shown in the drawing consists of a pair of animal skins 10, 11 which are generally circular. In addition, there is a layer 12 between the skins made of high-density plastic, e.g. polyethylene.

At the outer edges, the skins 10, 11 and the layer 12 are around one annular holder 13 folded and are by an annular Clip 14 held, which is rolled over the skins. The clip 14 is mounted in use in a housing that has a part the control or regulating device forms.

Furthermore, a member 15 is provided which is movable in the housing and has a rod portion 16 which is provided with a head 17 of reduced diameter so that there is a flange is formed. A pair of disks 18, 19 are mounted on the head part, and the skins 10, 11 and layer 12 are between the Discs arranged. The discs 18, 19 are held on the head part 17 by a spacer element 20, which in turn on the headboard 17 by rolling over the end face of the headboard is attached. The outer edges of the discs are rounded so that there are no sharp edges with the skins in use

209 82 5/07 69

Come into contact. In addition, in the specific example, the disks are slightly curved ₄ so that a recess 21 for attaching a helical spring (not shown) is created.

The presence of the high density polyethylene layer minimizes air leakage through the membrane without significantly increasing the stiffness of the membrane. aside from that the plastic layer does not deteriorate at operating temperatures, which can occur when using the control or regulating device, and it also withstands the use frequent deflections of the membrane.

Claim ί

209 82 5/076 9

Claims (1)

Claim Diaphragm for a pneumatic control or regulating device, characterized by a pair of animal or synthetic Skins (10, 11) which are arranged with their flat sides to one another and between which there is a layer of a high density Plastic is located, which is flexible and does not significantly increase the stiffness of the membrane. 25 377
U / Se 209825/07 6 3