WO2009080633A1

WO2009080633A1 - Flow sensor for fluid media

Info

Publication number: WO2009080633A1
Application number: PCT/EP2008/067668
Authority: WO
Inventors: Robert Buck
Original assignee: Robert Buck
Priority date: 2007-12-20
Filing date: 2008-12-16
Publication date: 2009-07-02
Also published as: DE102008062521A1

Abstract

The invention relates to a flow sensor for fluid media having a moving body (6), which is mounted in a housing (2), and which at least partially projects into the fluid medium or comes into contact therewith, and can be changed in its position relative to a sensor element (26) against a restoring force as a function of flow, and the sensor element being a position detection unit which operates without contact, wherein said housing (2) has an inlet channel (24) and an outlet channel (25) for said fluid medium. According to the invention, the sensor element (26) is disposed in the area of the inlet channel (24).

Description

Flow sensor for fluid media

description

The invention relates to a flow sensor for fl uid media with a mounted in a housing movement body, which at least partially protrudes into the fluid medium or comes into contact with this and against the force of gravity or a restoring force flow-dependent in its position relative to a sensor element variable and the sensor element Part of a non-contact position detecting device, wherein the housing has an inlet and an outlet channel for the fluid medium, according to the preamble of patent claim 1.

Flow sensors with a housing and with a sensor element arranged in the housing are explained, for example, in WO 2005/124291 A1.

Flow sensors can be used in a variety of applications. Thus, applications in the field of process engineering or machine tools are conceivable. In the cases mentioned, the flow sensors serve the flow or the flow velocity of a fluid medium, for. As air, water, oil, lubricant or the like, to measure, so that appropriate monitoring, control and monitoring tasks can be solved. In order to reduce the costs in the production of flow sensors, WO 2005/124291 Al has been proposed to provide a projecting into the flowing medium lifting body, the lifting body movably guided on a housing and depending on the flow of the medium to be monitored against the Restoring force of a arranged between the housing and the lifting element return element is movable. The sensor element is preferably as a non-contact proximity sensor, for. B. proximity switch and generates a dependent on the position of the lifting body signal. The return element, which is located between the housing and the lifting body may be formed as a mechanical, magnetic or electromagnetic element, in the simplest case, a spring is used, against the spring force of the lifting body is deflected by the flow of the medium. According to one embodiment of the prior art, the lifting body has a circumferential collar, said collar is formed so that the flow sensor additionally has the function of a check valve. As a result, instead of a check valve present in a water supply system, the flow sensor can be screwed into the connecting piece of a pipe already provided for the check valve. In order to achieve a sufficient stroke even with relatively small flows or flow changes, a cylindrical section is formed on the lifting body according to the prior art between the projecting in the installed state in the tube end of the lifting body and a circumferential collar.

As already stated, a magnetic proximity switch is used as the sensor element, wherein a permanent magnet is arranged in the lifting body. If according to the teaching of WO 2005/124291 A1 the lifting body is moved in the direction of the housing due to a present flow of the medium to be monitored, this leads to a reduction in the distance between the magnetic proximity switch and the permanent magnet, which triggers a switching signal. As a magnetic proximity switch so-called GM R cells (Giant Magnetor Resistor) are suitable.

In all cases of the state of the art according to WO 2005/124291 A1, it is assumed that the housing is preferably cylindrical, wherein the lifting body is movably guided in the housing. With appropriate flow conditions, the lifting body moves in the direction of the housing outside, against the restoring force of a spring located there. The flow sensor is attached to the lifting body opposite end portion on or in the housing. This results in a relatively large distance between the actual sensor element and the lifting body having a permanent magnet. At low flow rates, the lifting body is only deflected by a small amount with the result that no sufficient measuring signal is available and the measuring accuracy is insufficient.

From the above, it is an object of the invention to provide an advanced flow sensor for fluid media with a mounted in a housing movement body and with a sensor element, which is a has higher measurement accuracy, especially at low currents and small deflections of the moving body. Furthermore, a light and secure adjustment and adjustability of the sensor element should be ensured.

The object of the invention is achieved with the combination of features according to claim 1, wherein the dependent claims represent at least expedient refinements and developments.

Accordingly, it is an essential principle of the invention to arrange the sensor element in the region of the inlet channel at a predetermined distance to the moving body, not on the installation side of the moving body, but on the opposite, deviating from the prior art side. This results in the advantage that the distance of the moving body to the particular GM R measuring cell in the closed state with completely lowered movement or at low flow velocities is very low and at the GM R measuring cell a correspondingly large magnetic field can be detected, whereby the accuracy the measurement is improved.

In order to achieve the highest possible path resolution, the GM R-Messzel le is arranged axially to H ubbewegung, with lower requirements, other positional relationships are possible.

In a first embodiment of the flow sensor according to the invention, the sensor element, in particular the GM R measuring cell, is arranged on or in the housing in the region of the inlet channel. Here, the measuring cell with a correspondingly thin-walled housing section z. B. are fastened cohesively on the outside. Alternatively, a blind hole can be formed in the housing into which a sensor with a corresponding measuring cell is screwed.

In a further embodiment of the invention, the sensor element can be arranged in reaching into the inlet channel. In this embodiment, instead of a blind hole Durchgangsbohru ng is available as a threaded hole and it is screwed into the threaded hole with the sensor with measuring cell. In particular, in this embodiment, the Distance between the sensor and the moving body, the z. B. is designed as a lifting body, easily adjustable for calibration purposes.

In principle, the sensor element is arranged at a predetermined distance from the inflow side of the movement or lifting body which comes into contact with the fluid medium and essentially opposite this side. This results in the desired greater approximation between moving or lifting body and the sensor element, in particular with small deflections of the moving or lifting body, in particular at low flow and flow rates of the fluid medium.

The movement or lifting body may have a stop surface for closing an opening located between inlet and outlet channel, so that a check valve or a check valve is produced in a similar form as in the prior art.

The movement or lifting body can be designed as a conical or conical valve, but also as a flap valve, wherein it is essential that a sufficient movement of the body takes place at corresponding flow conditions of the fluid medium in order to detect the flow or flow changes safely.

On or in the movement or lifting body is at least one permanent magnet is located, which provides the magnetic field detected by the sensor element.

As already explained, the sensor element can be designed as an inductive proximity switch or, in particular, a magnetic measuring cell.

The permanent magnet and the magnetic measuring cell are at least in the state of greatest approximation, i. H. with closed valve or closed flap, net angeord on a common axis.

The common axis can here correspond to the longitudinal axis of the moving or lifting body or run parallel to this. At least the coming into contact with the fluid medium portion of the moving or lifting body itself may have permanent magnetic properties, so that it is not necessary to embed a discrete permanent magnet in the moving or lifting body or to fix there.

In one embodiment of the invention may be located on the upstream side of the moving or lifting body opposite section another permanent magnet in or on the moving or lifting body or it may also have this section permanent magnetic properties.

The distance between the further permanent magnet or the corresponding movement or lifting body section and the sensor element is greater than the distance between the first permanent magnet or the corresponding movement or lifting body section and the sensor element. Another sensor element can the second Permanentmag Neten or the respective movement or Hubkörperabschnitt are arranged on the opposite side of the inflow side. In this embodiment, small deflections can preferably be detected by the first sensor element and larger deflections preferably by the second sensor element with a correspondingly larger overall measuring range and higher resolution.

At least the distance between the second sensor element and the permanent magnet (s) is adjustable for calibration purposes.

The predetermined distance between the sensor element and the moving or lifting body is determined in accordance with the metrological requirements such as resolution or measuring range and taking into account the properties of the respective sensor element and / or the permanent magnet.

The housing of the flow sensor is made of a non-magnetizable material, such as brass or aluminum, or may be made of plastic materials. In a preferred embodiment of the invention, it is possible to start from a sensor element having a cylindrical body or a cylindrical body portion with means for adjusting or adjustable attachment to an object. It is not assumed by a conventional attachment or adjustment by screw thread, but it is arranged on the cylinder surface of the sensor element circular wedges in the circumferential direction, wherein the object, z. B. a Strömu ngssensorgehäuse, a cylindrical opening or bore is provided with corresponding Kreiskeilausnehmungen. In Umfangsrichtu ng two to four circular wedges with a wedge slope in the range of substantially 1: 30 to 1: 200 can be provided.

By using a circular wedge connection with corresponding circular wedge profiling, it is possible to effect a radial clamping by twisting the sensor element, whereby large axial and tangential forces can be transmitted in any direction. The proposed circular splines are also easily solvable. It can therefore be moved in particular for comparison purposes by turning and relaxing the sensor element in the opening or bore in the sensor housing and thereby adjusted. When the desired position is reached in the longitudinal direction, twisting is then again carried out while maintaining the longitudinal position, whereby the desired surface pressure with self-locking occurs. Each of the circular wedges is codetermined by the mathematical function of a logarithmic spiral. The connection on the basis of the corresponding wedges in the joint surface produces a homogeneous surface pressure with sufficient self-locking and thus great reliability.

The preferred GM R measuring cells, which are magnetoresistive sensors, are arranged in Wheatstone bridge circuit. This Wheatstone bridge circuit can be deliberately detuned by an external circuit in order to obtain an output voltage which is substantially linear with respect to the detected path change of the moving or lifting body, so that an easily processable and meaningful measuring signal is available. The invention will be explained below with reference to exemplary embodiments and with the aid of figures.

Hereby show:

Fig. 1 shows a longitudinal section through a flow sensor of a first embodiment with a permanent magnet in the conical section of a moving or lifting body and a measuring cell, which is arranged in a blind hole of a Z-housing, wherein the latter is in the region of the inlet channel.

Fig. 2 is a presen- tation similar to that of Figure 1, in which case a conical movement or H ubkörper is reset with stop collar via a spring force.

3 is a sectional view through a flow sensor according to the third embodiment, wherein here a first and a second measuring cell are provided;

Fig. 4 is a sectional view through a flow sensor according to the fourth embodiment with an outside, z. B. materially fixed to the housing measuring cell;

5 is a sectional view through a flow sensor according to the fifth embodiment similar to that of Figure 2, but here a through hole is present, in which the sensor can be arranged with measuring cell preferably by screwing;

6 is a sectional view through a sixth embodiment variant of a flow sensor with a flap valve and a permanent magnet arranged therein and an external sensor with measuring cell in a standard valve tube;

Fig. 7 is an end view of Figure 6, seen from the plane VII-VII. a seventh embodiment with flap valve, wherein the sensor element is mounted close to the permanent magnet on the outside of the tube;

an eighth embodiment with flap valve, wherein the sensor element is disposed in an annular groove of the tube in the vicinity of the effective range of the permanent magnet;

a ninth embodiment with flap valve similar to the illustration of FIG. 8, wherein here the sensor element is inserted into a through hole in the pipe;

a sectional view through a flow sensor with flap valve according tenth embodiment and first and second measuring cell, wherein the flap valve is in the oblique seat of a branch of the housing;

a sectional view through a flow sensor according to the eleventh embodiment similar to that of Figure 11, but with only a single measuring cell.

a twelfth embodiment of a flow sensor with

Flap valve, wherein the flap valve is in a 90 ° housing and a flap made of metal is detected directly by a cohesively attached outside the housing sensor;

a thirteenth embodiment of a flow sensor with flap valve, wherein the flap valve made of elastic material between a rigid retaining ring u nd a support ring is held, wherein here the flap is designed as a bypass valve flap and the sensor is screwed into the housing;

an exploded perspective view of the embodiment of FIG. 14; a fourteenth embodiment of a flow sensor with

Flap valve, wherein the flap of elastic material is held between a rigid retaining ring and a counter ring and is designed as a swing flap, and two sensors which are located both upstream and downstream of the flap in the housing and cooperate with the permanent magnet located in the flap, in addition, the flow direction is detectable;

an exploded perspective view of the embodiment of FIG. 16;

a fifteenth embodiment of a flow sensor with a cone valve in a Ω-housing, wherein the permanent magnet sensor arrangement substantially corresponds to that shown in FIG. 3;

a sixteenth embodiment of a flow sensor with an integrated in a housing metallic valve flap and an inductive sensor in the inlet region and a further inductive sensor in the outlet region;

a presen- tation of a flow sensor similar to that of FIG. 19, but with a valve flap, which has an integrated permanent magnet, in which case the sensors are designed as magnetic sensors;

a further embodiment of a Schrägsitzventils with spring-loaded check valve, wherein the sensor is fixed in an insert clamped;

and 22b sectional views of the sensor and the insert part in the region of the clamping zone, wherein the sensor can be adjusted and fixed by circular wedge connection technology; Fig. FIG. 23 shows a perspective section of the insert part with sensor according to FIG. 21 and FIG

Fig. 24 is an inclined seat valve with valve housing and housing branch, wherein two sensors are used.

The embodiments described below have in common that the sensor element in the form of a measuring cell, in particular a GM R-ZeIIe, not on the same installation side of the moving or lifting body is arranged, but on a quasi-opposite side. This makes it possible, the distance of the moving or lifting body to the measuring cell, d. H. to minimize the sensor element, at low flow rates, so that the sensor element detects a fairly large magnetic field, with the result of an increase in measurement accuracy. It is assumed that the sensor element at a predetermined distance from the coming into contact with the fluid medium side of the movement or lifting body substantially opposite to this side opposite. From this it can be deduced that the fluid medium is in the corresponding application of the flow sensor between the sensor element and the moving or lifting body.

Also, as described in the examples below, it is possible to provide moving or lifting bodies which each have permanent-magnetic sections or permanent magnets inserted at their opposite ends. Such a quasi-standard lifting body could then be used in combination with differently arranged sensor elements application and z. B. be used optimally in the event that as small as possible movements and thus pressure fluctuations are to be detected; On the other hand, in the range of maximum movement and deflection of the moving or lifting body still a useful resolution in metrological terms is given. The strength of the magnetic field of the permanent magnet and the distance to the sensor element is selected such that the GMR measuring cell used as the sensor element is preferably not operated in its non-linear saturation region.

The flow sensor IA according to FIG. 1 initially has a non-magnetizable housing 2, which, for. B. brass material or aluminum or a Aluminum alloy exists. The housing has an inlet channel 24 and an outlet channel 25, based on the arrangement of the housing or the flow sensor 1 in a fluid circuit.

The housing 2 further has an opening for a screw-3, which receives a movement or lifting body 6 mounted therein. In the example shown in FIG. 1 is the movement or lifting body 6 by means of a ring magnet 23 which is located in the screw 3, magnetically guided and biased by the resulting magnetic force of the ring magnet 23.

At the inlet channel 24 facing end is in or on the moving or lifting body 6, a permanent magnet 19 as an influencing element available. The reaching into the inlet channel 24 section of the moving or lifting body 6 has a conical or conical shape.

In essence, the position of the permanent magnet 19 in the movement or lifting body 6 opposite a blind hole 22 is introduced in the housing 2.

In this blind hole 22, the sensor or the sensor element 26 is fixed with measuring cell 27.

In the flow sensor I B of FIG. 2, a similar basic structure of the housing 2 with inlet channel 24 and outlet channel 25 is present. In contrast to the illustration of FIG. 1, however, no magnetic spring biasing force for the movement or lifting body 6 is provided here, but it is a simple spring element 8, z. B. a helical compression spring, used in the screw 3. The screw-in part here still has a guide bore 12 and a protective cap 11.

The moving or lifting body 6 has in the embodiment of FIG. 2 still a circumferential sealing collar 9, which comes in contact with the valve seat 10 in the closed state.

Also in this embodiment of the invention is the sensor element 26 with Messzel le 27 in the region of the inlet channel 24 in turn in one Sacklochbohru ng 22, which may be provided with an internal thread, which corresponds to an external thread of the sensor element 26.

In the case of the flow sensor IC according to FIG. 3, a first sensor element 26 and a second sensor element 28 are provided, wherein the arrangement of the sensor element 28 with the measuring cell 29 essentially corresponds to that of the prior art, ie. H. Here is the sensor element 26 in the screw 3.

Depending on the given flow conditions, d. H. either only a slight or even stronger movement of the moving or lifting body 6, either the first sensor element 26 with measuring cell 27 located there is activated and read out, or the second sensor element 28 with the measuring cell 29 located there is selected. Alternatively, the first and the second sensor element can be connected to a bridge circuit. In this case, both sensor output signals are evaluated via the bridge circuit, so that an increase in the measurement accuracy is possible.

The variant embodiment of a flow sensor I D according to FIG. 4 corresponds structurally to that according to FIG. 2 with the difference that the housing 2 has a smaller thickness in the region of the arrangement of the sensor element 26 with measuring cell 27 in order to effect the smallest possible distance between the measuring cell 27 and the permanent magnet 19. In the present case according to FIG. 4, the sensor element 26 on the outside of the housing at this z. B. cohesively held by gluing.

The flow sensor IE in its embodiment according to FIG. 5 is of the basic structure with that of FIGS. 2 and 4 comparable. However, here a through-bore 21 in the housing 2 is introduced in the region of the inlet channel 24 in order to receive a screw-in sensor element 26 with a corresponding measuring cell 27. Without appreciably influencing the flow cross-section of the inlet channel 24, the spacing between the permanent magnets 19 as influencing element and the measuring cell 27 can be further reduced in this embodiment, and the response at low flow velocities can be improved. While maintaining the principle according to the invention, according to which the sensor element is arranged in the region of the inlet channel at a predetermined distance from a moving or lifting body, FIGS. 6 to 17 embodiments IF to IP of the moving or lifting body in the form of a flap valve 30. The flapper valve 30 according to FIGS. 6 to 9 is located inside a tube 5, which forms the housing in this embodiment. The valve flap 37 can perform a film hinge 34 opening and closing movements depending on flow conditions between the inlet channel 24 and outlet channel 25 and is mounted on a retaining ring 35 and a fixing ring 36, wherein the fixing ring 36 sealingly abuts a valve seat 10 on the one hand and on the other hand with a collar 9 of the valve flap 37 is in the closed position in contact.

The sensor element 26 with measuring cell 27 is outside the tube 5 z. B. fixed by material connection.

The permanent magnet 19 as an influencing element is inserted into the valve flap 37 or there by molding with the valve material, for. As a plastic or an elastomeric material, embedded.

When the flapper valve 30 opens, d. H. the valve flap 37 moves into the open position, the position of the permanent magnet 19 changes and the distance A between the magnet 19 and the measuring cell 27 increases, so that a corresponding measuring signal can be triggered.

In the tube 5 is in the embodiment of FIG. 9 a groove, z. B. in the form of an annular groove 13, introduced. The sensor element 26 with measuring cell 27 can then extend at least partially into this annular groove and be fixed there. Not only is a secure mechanical fastening of the sensor element 26 given via the annular groove 13, but the distance between the measuring cell 27 and the permanent magnet 19 in the valve flap 37 is reduced.

In the illustration according to FIG. 10, the sensor element 26 with measuring cell 27 is introduced into a through-bore in the valve tube 5 and is at least partially reaching into the medium flow M. In the embodiment of the flow sensor II according to FIG. 10, in turn, a tubular housing 5 with a flap valve 30 located therein is assumed. In the case of the illustration of FIG. 10, however, the measuring cell 27 is located in a sensor element 26 which is fastened in the inlet channel 24 via a through-bore 21.

Fig. 9 shows the eighth embodiment of a flow sensor I H with flap valve 30. Again, there is a Permanentmag net 19 in or on the valve flap 37. The flap valve is in the illustration of FIG. 9 inserted in the inlet channel 24 of a pipe. As shown in FIG. 10, the flap valve 30 is located in the region of the outlet channel 25.

The principle of the flap valve 30 is according to the examples I K and I L in Figs. 11 and Fig. 12 also in a tubular housing 5 with branch 31, so that a slanted seat of the valve flap 37 results applicable.

The valve seat 10 is formed on a projection 32. In the branch 31 opposite part of the projection 32 a Sacklochbohru ng 22 is introduced, which receives the sensor element 26 with measuring cell 27 to provide the smallest possible distance between the measuring cell 27 and the permanent magnet 19 in the flapper valve 30.

The flow sensor I L of FIG. 11 is based on the basic structure of a flap valve, which is located obliquely in a tubular housing 5, as already explained. In addition, however, a second sensor element 28 with a second measuring cell 29 is provided here. The second sensor element 28 is in turn held in the tubular branch 31 via a screw-in part 3 and is therefore located on the quasi-opposite side of the first sensor element 26.

The dashed deflection position of the valve flap 37 of FIG. 11 leads to a closer approximation of the Permanentmag Neten 19 to the second measuring cell 29, so that in this case the second sensor element 28 provides an advantageously evaluable measuring signal. With smaller deflections of the valve flap 37 there is a smaller distance to the first sensor element 26 with the measuring cell 27 located there, so that this measuring cell is preferably used for the evaluation.

In the embodiment of a flow sensor IM of FIG. 13, there is a so-called 90 ° housing 2, which has an access closed by a screw cap 33.

In the example of FIG. 13, the valve flap 38 of the flapper valve 30 is made of either a metallic, especially ferritic material or provided with such a coating, so that, based on the housing 2 Außenz Messzel le of the sensor element 28 a change in position of the flap valve 30th safely detected.

According to the thirteenth embodiment of a flow sensor IN of FIG. 14, a flap valve 30 is inserted into a tube 5, wherein the valve flap 37 is made of an elastic material and is fixed between a rigid retaining ring 39 and a support ring 40. The design and position of the support ring 40 with three support struts 41, the execution of the valve 30 and the rigid retaining ring 39 is in the illustration of FIG. 15 recognizable in perspective.

In the embodiment of FIGS. 14 and 15, the sensor element 26 is in the acting as a valve housing tube 5 z. B. introduced by screwing into an existing hole there.

In the fourteenth embodiment of a flow sensor IP with flap valve according to FIGS. 16 and 17, the valve flap 37 is again made of an elastic material. Two sensor elements 26 are respectively arranged on the inlet and outlet side of the valve flap 37 in the tube 5, wherein the valve flap 37 of the flap valve 30 is designed as a swing flap, so that in addition the flow direction can be detected. The swinging flap 37 is located in the example of FIGS. 16 and 17 between two retaining rings 39 and 40 within the tube 5, wherein the support ring 40 comes to rest on the collar 9 of the tube 5 and the rigid retaining ring 39 is pressed. Fig. 18 shows a fifteenth embodiment of a flow sensor IQ of a type as shown in FIG. 3 has already been explained, but here the course of the channels 24, 24a and 25 is not Z-shaped, but has a Ω- form.

The sensor element 28 can be embodied as an inductive sensor unit and is formed by a tubular damping element arranged on the rear side of the lifting body 6, which influences the inductively operating measuring cell 29.

Fig. 19 shows a sixteenth embodiment of a flow sensor I R. There is also a valve housing 2 with an inlet channel 24 and an outlet channel 25. In its function as a backflow flap, a valve flap 38 made of a metallic material can open and close a recess in the valve housing 2 in the flow path between inlet channel 24 and outlet channel 25. The opening position is shown by dashes.

A sensor element 26 extends into the inlet channel 24. This sensor element 26 is z. B. formed as an inductive sensor.

A second sensor element 28 is provided with a plastic protective sleeve 42 and fixed by screwing in the housing 2. A sealing compound 43 fills a remaining gap between the plastic protective sleeve 42 and an insert 44.

Furthermore, a metallic sleeve 45 is provided, which does not extend to the sensitive region of the sensor 28.

Changes in the position of the valve flap 38 are reliably and highly sensitively detected by the two sensors 26 and 28 alike or by subtraction of the sensor output signals.

In the seventeenth embodiment of a flow sensor IS of FIG. 20 is assumed that a similar housing construction with valve flap 38, as shown in FIG. 19 has been shown and already explained. However, in the exemplary embodiment according to FIG. 20, magnetically sensitive sensor elements 26 and 28 are used. In addition, a permanent magnet 19 is embedded in the valve flap 38. In a change in position of the valve flap 38 changes due to the also changed position of the permanent magnet 19 with respect to the sensor elements 26 and 28, the indicated in Fig. 20 magnetic field. This magnetic field change can be reliably evaluated by the sensor elements 26 and 28, again on the basis of the determination of absolute values, but also by subtraction of the measurement signals.

The proposed embodiments of the flow sensors are particularly applicable to so-called two-wire flow meters with switching output, d. H. in such inductive resonant circuit proximity switches or GMR or AMR magnetic sensors in which the requirement can be met, according to which in the switched state, the Restspannu ng is only a fraction of the operating voltage and wherein in the locked state, the residual current is very small, thus subsequent Evaluation stages do not interpret the residual current as a measurement signal.

The Fig. 21 shows a further embodiment of a Schrägsitzventils but with spring loaded valve flap 38, in which case a sensor 17 is not screwed into the through hole of a valve cover, but is fixed within a trained insert 44 du rch jamming. The valve flap 38 is articulated via an axis 54.

The insert member 44 is fixed relative to the valve flap 38 in the valve housing 2 instead of a conventional valve cover.

The insert 44 has a recess in the manner of a blind hole for receiving the sensor 17, wherein the recess in the upper, flap-distant region is designed as a circular wedge recess 83 and in the lower, flap-near region as a cylindrical recess 84.

The sensor 17 has at the connection cable end a handle part 80, for example, designed as a surface knurling. The following sections are designed as circular wedge 81 and cylinder 79. By twisting clamped the sensor 17 within a clamping zone 86 frictionally in the Sacklochbohru ng of the insert 44th

According to FIG. 20, the representation according to FIG. 21, the sensor 17 is provided with a magnetic sensor 61. Alternatively, other sensors can be used, for example, inductive sensors.

The Fig. 22a and 22b each show a sectional view of the sensor 17 and the insert part 44 in the region of the clamping zone 86 (see FIG. 21), wherein the sensor can be adjusted and fixed by circular wedge connection technology.

On the lateral surface of the sensor 17 are in the example shown, three circumferentially spaced circular wedges 81. These circular wedges 81 extend over a first portion of the longitudinal axis of the sensor, wherein in a second portion of the sensor is cylindrical. It is also conceivable to extend the circular wedges 81 over the entire lateral surface of the sensor 17.

On the insert 44 or on an object 82 to which the sensor 17 is to be attached, there is at least one cylindrical opening or bore, the corresponding cylindrical opening or bore having corresponding circular key recesses 83 (see FIGS. 22a and 22b).

In the example shown, three circular wedges 81 with corresponding three circular wedge recesses 83 are provided on the object 82. The circular spline slope may be in the range of substantially 1: 30 to 1: 200 here.

With the introduction of the sensor 17 and the circular wedges provided therein in an object 82 which has a complementary opening with Kreiskeilausnehmungen, and then twisting creates a radial bias, whereby large axial and tangential forces can be transmitted in any direction. The proposed circular wedge connection is again easily detachable via an oppositely directed rotational movement. The Fig. 22a shows a sectional view in the unclamped state. In this state, z. B. by means of the handling part 80 of the sensor 17 slightly shifted in Längsachsenrichtu ng and z. B. the desired adjustment to find the window area or a work point done. If the desired window area is present and z. B. is signaled with an optoelectronic display, in turn, by means of the handling part 80, the rotation without changing the selected or reached position in the longitudinal axis direction. An adjustment or the execution of a setting process is much faster and easier than it would be at a z. B. screw thread is the case, where it is z. B. when tightening a lock nut to obtain the selected position can come to a misalignment.

The circular wedge shape, as shown in FIGS. 22a and b recognizable, for example, by a logarithmic spiral writable. However, there are also other clamping acting wedge shapes in question. Due to the corresponding wedges in the joint surface results in a homogeneous surface pressure, so that not only an optimal transmission power in tightening direction, but also sets an optimal self-locking in the release direction.

However, it is also possible a quasi-kinematic reversal to the effect that the sensor element is located in a body having an annular sleeve. In this case, the object to which the sensor is to be attached will have a cylindrical extension which has the circular wedges over its circumferential surface as explained.

In this embodiment variant, the sleeve-shaped sensor would be displaceable over the cylindrical rod and fixable by rotation.

Fig. FIG. 23 shows a perspective section of the insert 44 with sensor 17 according to FIG. 21.

The circular wedge recesses 83 extend substantially in the upper part of the recess for the sensor 17 in the insert part 44. The lower part is, as already explained, made cylindrical. However, it is also conceivable that Circular wedge recesses over the entire recess extending in the longitudinal direction form.

In particular, it is also possible to provide a sleeve which has circular wedge recesses on its inner circumferential surface. If, instead of the above-explained recess of the insert part 44, a simple blind hole is now provided for receiving the prefabricated sleeve, a receptacle for a sensor 17 with circular wedge connection technology can be provided in a simple manner by pressing the sleeve into such a blind hole.

If the circular wedge recess extends over the entire longitudinal extent within the insert part 44, a cylindrical section 79 of the sensor 17 can be dispensed with.

If a cylindrical section 79 is provided on the sensor 17, the diameter of this section can be selected at most in accordance with the clear or free diameter of the circular wedge recess.

In the example shown in FIG. 23, the diameter of the cylindrical portion 79 is chosen to be significantly smaller than the possible free diameter. In principle, however, it is also possible to adapt the cylindrical recess 84 corresponding to this section to the diameter of the cylindrical section 79.

Furthermore, the sensor 17 has an optoelectronic display 85. In the case shown, this display or a window of this display in the area of knurling 80 is attached. However, other displays may be provided. In particular, it is conceivable to arrange the displays offset by 180 ° or 90 ° in order to have the display always in view even when the sensor is rotated. In a further embodiment, also or exclusively a display on the sensor termination in the cable region 87 may be provided, so that the display is visible from above. Furthermore, it may be provided to terminate or cover the cable region 87 transparently so that an optoelectronic display remains visible through this transparent termination. As optoelectronic displays are particularly light emitting diodes into consideration. Fig. 24 again shows an oblique seat valve with valve housing 2 and a housing branch. In the housing branch an insert 44 is attached, as already shown in FIG. 21 explained.

In the insert part 44 of the sensor 17 is received, in a recess which allows a circular wedge connection with a sensor 17 in two-wire technology. In contrast to the illustration of FIG. 70, the insert part 23 has a guide section 88, which is oriented in the direction of the valve seat.

The guide portion 88 receives a longitudinally displaceable valve body 89, at its end oriented toward the valve seat, a permanent magnet 90 is located. The preferably cylindrically designed valve body 89 is biased by means of a coil spring 91 in the direction of the valve seat. A change in position of the valve body 89 leads to a movement of the permanent magnet 90, which can be detected both by the sensor 17 and by a further sensor 26 analogous to FIG. The valve body 89 is in the example shown in FIG. 24 executed as a spring-loaded check valve assembly.

LIST OF REFERENCE NUMBERS

IA-S flow sensor

2 housings

3 screw-in part

5 pipe

6 lifting bodies

8 spring element

9 fret

10 valve seat

11 protective cap

12 pilot hole

13 annular groove

17 sensor

19; 90 permanent magnet 21 hole

22 blind hole

23 ring magnet

24 inlet channel

24 connecting channel (Fig. 18)

25 exhaust duct

26 sensor element

27 measuring cell

28 sensor element

29 measuring cell

30 flap valve (consisting of 37 + 34 + 35 + 36)

31 branch

32 advantage

33 screw cap

34 foil hinge between 37 and 39

35 retaining ring for 37

36 fixing ring for 35

37 valve flap (non-metallic & swing flap)

38 valve flap

39 rigid retaining ring (Figs. 14 to 17)

40 support ring (FIGS. 14 to 17)

41 struts (Fig. 15)

42 plastic protection sleeve

44 insert

45 metallic sleeve

A distance 19/27 in FIG. 6

M media stream (FIG. 10)

54 axis

61 magnetic sensor

62 stop

79 cylinders

80 handle part

81 circular wedge

83 circular wedge recess

84 cylindrical recess

85 display 86 clamping zone

87 Cable area

88 guiding section

89 valve body

91 coil spring

Claims

claims

1. Flow sensor for fluid media with a mounted in a housing moving body, which at least partially protrudes or comes into contact with the fl uid medium and against the force of gravity or a restoring force flow-dependent in its position relative to a sensor element is variable and the sensor element part a non-contact position detecting device, wherein the housing has an inlet and an outlet channel for the fluid medium, characterized in that the sensor element (26) in the region of the inlet channel (24) at a predetermined distance from the moving body (6) is arranged.

2. Flow sensor according to claim 1, characterized in that the sensor element (26) is arranged on or in the housing (2) in the region of the inlet channel (24).

3. Flow sensor according to claim 1, characterized in that the sensor element (26) is arranged reaching into the inlet channel (24).

4. Flow sensor according to one of the preceding claims, characterized in that the sensor element (26) is arranged at a predetermined distance from the coming into contact with the fluid medium upstream side of the moving body (6) and substantially opposite this side.

5. Flow sensor according to one of the preceding claims, characterized in that the moving body (6) has a stop surface for closing an opening between an inlet (24) and outlet (25).

6. flow sensor according to one of the preceding claims, characterized in that the movement body (6) is designed as a conical or flap valve.

7. Flow sensor according to one of the preceding claims, characterized in that in or on the movement kung body (6) at least one nibble influencing body (19), z. As a permanent magnet, a ferrite, a coil or the like is located.

8. Flow sensor according to claim 7, characterized in that the sensor element is designed as an inductive proximity switch, magnetic field-sensitive or magnetoresistive measuring cell (29).

9. Flow sensor according to claim 7 and 8, characterized in that the influencing body (19) and the sensor element (26) are arranged at least in the state of their closest approach on a common axis.

10. Flow sensor according to one of claims 1 to 5 and 9, characterized in that the common axis of the longitudinal axis of the moving body (6) corresponds to or extends substantially parallel thereto.

11. Flow sensor according to one of the preceding claims, characterized in that at least coming into contact with the fluid medium portion of the moving body (6) has permanent magnetic properties.

12. Flow sensor according to claim 7, characterized in that on the upstream side of the moving body (6) opposite section another, second influencing body (xx) is located in or on the body or this section has properties according nib according to the influencing.

13. Flow sensor according to claim 12, characterized in that the distance between the further, second influencing body (xx) or the corresponding moving body section (6) with influencing ngskörper- properties and the sensor element is greater than the distance between the first influencing body (xx) or the corresponding moving body portion and the sensor element.

14. Flow sensor according to one of the preceding claims, characterized in that a further sensor element (28) is provided.

15. Flow sensor according to claim 7 and 14, characterized in that the further sensor element (28) the second influencing body (xx), in particular designed as a permanent magnet (19), or the respective moving body portion (6) on the upstream side of the region is arranged.

16. Flow sensor according to claim 14 or 15, characterized in that at least the distance between the further sensor element (28) and the one or more permanent magnets (19) is adjustable for calibration purposes.

17. A flow sensor according to claim 1, characterized in that the predetermined distance according to the metrological resolution, the measuring range and in compliance with the properties of the respective sensor element (26, 28) is fixed.

18. Flow sensor according to one of the preceding claims, characterized in that the one or more sensor elements are formed as arranged in Wheatstone bridge magnetoresistive sensors.

19. Flow sensor according to claim 18, characterized in that the Wheatstone bridge circuit is deliberately detuned by external circuitry.

20. Flow sensor according to claim 19, characterized in that the detuning of the Brückenschaltu ng takes place to obtain an output voltage which is substantially linear to the detected change in path of the moving body (6).

21. Flow sensor according to one of the preceding claims, characterized in that the housing consists of (2) a non-magnetizable material such as brass, aluminum, aluminum alloys or plastic.

22. Flow sensor according to one of the preceding claims, characterized in that the sensor element (26; 28) has a cylindrical body (50) or body portion with means for adjusting or adjustable attachment to the housing (2), wherein on the cylinder surface (50) circular wedges (52) are arranged in the circumferential direction, wherein on the housing (2) a cylindrical Öffnu ng or bore with corresponding Kreiskeilausnehmungen (53) is provided.

23. Flow sensor according to claim 22, characterized in that in the circumferential direction two to four circular wedges (52) are provided with a wedge slope in the range of substantially 1: 30 to 1: 200.