DE1920843U - TRAVEL PRESSURE TRANSDUCER TO MEASURE SMALL TRAVEL - Google Patents

Description

German Patent Office

8 Munich 2

Zweibrückenstrasse 12

Utility model registration

Frede-Automatik KG., 4 Düsseldorf, Zimmerstrasse 19

"Displacement pressure transducer for measuring small distances"

The innovation relates to a displacement pressure transducer for measuring small distances. It is known to use such transducers to convert small measuring paths of a few millimeters into a ratio equal to, preferably pneumatic pressure of, for example, 0.2-1.0 kp / cm ^ and to measure this pressure which is equal to the measured value using a suitable pressure gauge , which is generally referred to as the working pressure, can also be applied in a known manner as a control or regulating variable. One such way-D _r uckwandler is used for scanning of cams or for measuring deflections of machine parts or for dimensional inspection of workpieces or the like.

Displacement pressure transducers of this type are connected to a constant inlet pressure and, in addition to a gate throttle, have one in front of a Axially movable throttle nozzle arranged on the measuring surface, as well as a feedback member which adjusts the throttle nozzle relative to the measuring surface on, which is acted upon by the working pressure that is set in accordance with the outlet throttling.

-2-

Postal checking account Essen 47247 · Commerzbonk AG., Düsseldorf, Depositenkasse Hauptbahnhof

According to the innovation, the throttle nozzle is on one, a working pressure chamber bounding by diaphragms of different sizes formed spring-loaded Membrärgstem attached, the in the returning Senses works.

In this way, a very simple and easy-to-use one is obtained and easy to manufacture measuring device, the membrane system is expediently housed in a housing, the one for the axial guidance of the Dro-Sseldüse serving coaxially to the Has membrane system arranged approach.

As an example of the innovation is on the drawing a displacement pressure transducer shown in section.

In a housing 1, which carries a connection piece 2 for the working pressure, is a membrane system formed from two membranes 3> 4 housed. The area of one membrane 3 is considerable smaller than that of the other membrane 4. Between the membranes 3j4 there is a working pressure space 5. With the housing

I is screwed a head piece 6 in which an adjustable Throttle 7 is housed and that with a connection piece 8 is provided for the form.

On the housing 1, a projection 9 is provided coaxially to the membranes 3, 4, in which a throttle nozzle 10 is axially guided. the Throttle nozzle 10 is connected to an intermediate piece 11 which is screwed to the plates of the membranes 3 »4. The intermediate piece

II has a transverse bore 12 opening into the working pressure chamber 5, with a longitudinal drift 14 continuing the nozzle channel 13 of the intermediate piece 11 is in connection. The ^ embran 4 is loaded by a spring 15, the pressure of which by a screw 16 is adjustable. In the mouth of the throttle nozzle 10 is a throttle body 17 out, which rests against a measuring surface, not shown. The deeper the throttle body 17 in the mouth of the

-3-

Throttle nozzle 10 penetrates, so the throttling of the air flow emerging from the throttle nozzle 10 is stronger.

A pressure source delivering a constant pneumatic pre-pressure is connected to the connecting piece 8. The air flow is throttled by the choke 7 and enters the working pressure chamber 5. A more or less large proportion of the air supplied exits the throttle nozzle via the transverse bore 12 and the channels 14, 13, and depends on the penetration depth of the throttle body 17. In the working pressure chamber 5, which is connected to a pressure gauge via the connection piece 2, a pressure is therefore set which is greater, the more the outlet from the throttle nozzle 10 is throttled. A regulating process takes place in order to produce a ratio equality between the outlet throttling and the working pressure that is established. The working pressure acts in the working pressure ^chamber 5 on the ivi embransystem 3, 4 against the spring 15 withdrawn and thus the outlet enlarged. If the working pressure is still too low, the force of the spring 15 predominates, whereby the throttle nozzle 10 is advanced and the outlet throttling is increased. In this way, each adjustment of the adjusting nozzle 10, ie each measuring path, is assigned a working pressure of the same ratio, the ^X1 embransystem 3, 4 acted upon by the working pressure acting in the sense of a return of a proportional controller.

-4-

One can cooperate with a throttle body 17 instead of Throttle nozzle 10 also use a simple throttle nozzle 10 ', which is arranged close to a measuring surface 18, so that the variable Outlet throttling takes place directly between the nozzle orifice and the measuring surface. In this case, too, the path to be measured is s equal to the adjustment of the nozzle 10 ', which is set under the influence of the controlled working pressure

~ * 5—

Claims (5)

RA. 155 609 * 3/26/65 S chut ζ talks 1) Distance-pressure transducer for measuring small distances with a pre-throttle and an axially movable throttle nozzle arranged in front of a Mei3fläehe as well as a return element which adjusts the throttle nozzle relative to the measuring surface and which is acted upon by the working pressure set according to the outlet throttling, characterized in that the throttle nozzle (10,10 ') limiting a working pressure in a space (5) spring-loaded ^M membranes (3,4) of different sizes formed embransystem is fastened, which acts in the returning sense. 2) displacement-pressure transducer according to claim 1, characterized in that the membrane system (3, 4) is housed in a housing (1), one serving for the axial guidance of the throttle nozzle (10, 10 ') having the same axis as the membrane system (3, 4) arranged approach (9). 3) path-pressure transducer according to claim 2, characterized in that the inlet pressure connection (8) and the gate throttle with the housing $) (7) having head piece (6) is screwed. 4) path-pressure transducer according to one of claims 1 to 3, characterized in that that in the throttle nozzle (10) a throttle body (17) resting against the measuring surface is guided. -6- 5) path-pressure transducer according to one of claims 1 to 4, characterized
characterized in that an intermediate piece (11) which connects the two membrane plates of the membrane system (3,4) and to which the throttle nozzle (10,1O ¹ ) is attached, has a transverse bore (12) between the membranes (3j4) which is in a the longitudinal bore (14) of the intermediate piece (11) continuing the nozzle channel (13) opens.