KR0181974B1 - Micrometrical dosing device - Google Patents

Abstract

The metering device comprises a metering valve 11 mounted inside the body 12 having an inlet 13 and an outlet 14. An inlet 13 for the material is formed in a block 15 housed in a cavity of the body 12 and secured to the body by screws 16. The body 12 has a cylindrical cavity 18 sealed by a side cover 19 fixed to the body 12 by screws 20. The cavity 18 comprises a pusher consisting of a first part 2 connected to the drive 22 and a second part 23 connected to the return spring 24. The valve consists of a slide valve 33 comprising an upper surface 34, a flat lower surface 35 and a lateral conduit 36 formed between the upper surface 35. This slide valve 33 is slidably moved on a plate 37 having two transverse ducts in communication with the outlet 14 for the metered material.

Description

Micrometer

1 shows an axial sectional view of a metering device according to the invention, more precisely, a metering valve mounted inside the body of the device,

2 shows a plan view of the pusher, the slide valve and the centering ball of the slide valve, where the assembly is separated from the body of the device,

3 shows a perspective view of the compression spring pressing the upper surface of the slide valve,

Figures 4a, 4b and 4c show three different positions of the pusher and the slide valve relative to the conduit of the fixed plate.

* Explanation of symbols for main parts of the drawings

10 metering device 11 metering valve

12 body 13 inlet

14 outlet 16 screw

18: cylindrical cavity 19: side cover

21: first part 22: drive device

23: second part 24: return spring

26: movable pin 31: lock nut

32: adjusting screw 33: slide valve

38: duct 39a, 39b: side groove

40: compression spring 50: pusher

52: groove

The present invention includes a metering valve body, an inlet for the material to be metered, an outlet for the metered material and a metering valve mounted inside the body between the inlet and the outlet and which can be opened or closed. It relates to a micrometer measuring device.

Known and most frequently used micrometering devices are commercially available under the name proportional valves. The proportional valve includes a body having a generally cylindrical cavity in which a linearly movable cylindrical element is received. This element includes peripheral grooves that cooperate with grooves formed in the body to allow or block the passage of material to be metered from the inlet duct toward the outlet duct. The sealing of the device depends on the precision of the machining of the cylindrical cavity of the body and the movable cylindrical element housed within this common.

It is recognized that such sealing is difficult to achieve due to the gap inevitably present between the wall of the body defining the cylindrical cavity and the outer wall of the movable cylindrical element in order to avoid too much frictional force during the displacement of the movable cylindrical element. come. These gaps are the cause of leakage which results in a wrong weighing result. The reduction of this gap, which has the effect of improving the seal, increases the tightness between the parts, thereby increasing the friction and wear, resulting in a loss of the seal, which is cut out, ie resulting in leakage. This constitutes a major drawback of this type of metering device and the present invention aims to provide a solution to this drawback.

For this purpose the present invention relates to a metering valve, the metering valve having a flat surface and having at least one duct in communication with the outlet for the metered material and which rests on the flat surface of the stationary plate. A slide valve having a flat surface disposed therein that allows the flow of material to be metered towards the duct of the stationary plate when in one of the positions corresponding to the opening of the metering valve and shuts off the metering valve. At least one passage arranged to stop this flow when in one of the corresponding positions, and wherein the passage of the slide valve has an outer surface of the slide valve connecting the flat surface to the opposite surface. Including a groove having at least one shape formed in at least one of the It is composed. The groove having the above shape advantageously has a cross section which is at least approximately V-shaped.

According to a preferred embodiment, the passageway of the slide valve has at least one transverse conduit which appears on one side of the flat side and on the other side of the slide valve to communicate with the inlet for the material to be metered. It is included.

Preferably, the slide valve has a lower surface consisting of the flat surface reclining on the flat surface of the fixed plate, an upper surface opposite the lower surface, two side surfaces, and generally a V-shape. It is comprised by the one block containing two cross sections each containing the recess which has a cross section in shape.

Preferably, the slide valve is coupled to a drive device arranged to linearly move it in one direction and a return spring arranged to linearly move in the opposite direction.

Advantageously the block constituting the slide valve is mounted in a central cavity formed inside the longitudinal pusher, the pusher leaning against the first end and the return spring which lean on the drive. It has a second end.

Preferably, the drive devices include electric motors, but they can also be configured as electromagnets or pneumatic or hydraulic devices.

In this embodiment, the block constituting the slide valve is mounted to the central cavity between two centering balls each engaged with a groove having a shape formed in the end faces of the block.

The device according to the invention preferably comprises a compression spring arranged to apply pressure on the flat top surface of the block. The compression spring is mounted between a bearing ring comprising a surface cast in contact with an upper surface of the block forming the slide valve and an element having at least one passageway for communication with the inlet to the material to be metered. It is done.

Preferably, the bearing ring comprises at least one connecting nipple arranged to engage a conduit through the slide valve.

The invention will be better understood by reference to the embodiments and the description of the accompanying drawings.

In connection with FIG. 1, the metering device 10 comprises a metering valve 11 mounted inside the body 12 having an inlet 13 for the material to be metered and an outlet 14 for the material to be weighed. It is composed. This material to be metered is generally a material having the viscosity of a liquid or paste, but may also consist of a powder whose flow is similar to that of a fluid.

The inlet 13 for the material is received in a cavity of the body 12 and is formed in a block 15 secured to the body by a flat head screwdriver 16. The sealing between the block and the body is ensured by a 0-ring 17. The body 12 is composed of a single block having a cylindrical cavity 18 mounted therein with a movable element of a metering valve. This cavity is sealed by the side cover 19, which is fixed to the body 12 by a flat head screw 20 in a plate or four-hole machined in the wall.

The cylindrical cavity 18 comprises a longitudinal pusher composed of a first portion 21 coupled with the drive 22 and a second portion 23 coupled with the return spring 24. These two parts are connected to each other by a central part with grooves therein and are represented more precisely in FIG.

In the embodiment described, the drive 22, which is an electric, pneumatic or hydraulic motor or electronic, is fixed to the body 12 of the metering valve by screws 25 and on the back of the first part 21 of the pusher. It includes a movable pin 26 designed to be expected. This first part 21 of the pusher feeds a centering stop 27 on which one ball 28 is mounted. In a similar manner the second part 23 of the pusher feeds the centering stop 29 on which one ball 30 is mounted. The return spring 24 is supported by the cover 19 on the one hand and by the lock nut 31 clamped to the outer threaded portion of the adjustment screw 32 on the other hand.

The actual metering valve is a block comprising an upper surface 34, a flat lower surface 35, and a transverse conduit 36 formed between the upper surface 34 and the lower surface 35, which may have a flat or other shape. Essentially includes a slide valve 33 is configured as. This slide valve 33 is translated in a sliding manner over a plate 37 having two transverse ducts 38 in communication with the outlet 14 for the metered material. The slide valve 33 additionally includes grooves 39a and 39b in the V-sectional shape on the opposite side, respectively, which grooves are engaged with the balls 28 and 30, respectively, and are movable. It cooperates with balls 28 and 30 respectively to ensure accurate centering of the slide valve. These grooves may or may have another action described below.

The slide valve 33 is pressed against the upper surface of the plate 37 by a compression spring 40 supported by an annular element 41 having a passage 42 for communication from the inlet 13 of the metering valve. Lose.

The sealing ring 43 having a shape ensures the sealing between the first part 21 of the pusher and the body 12 of the metering valve. The sealing ring 44 shaped in the same way ensures a seal between the body 12 and the second part 23 of the pusher.

2 shows the pusher 50 composed of the first part 21 and the second part 23 which are firmly connected to each other by the central part in which the groove 52 is formed as described above. The groove has grooves 39a having a shape having a cross section of the upper surface 34, the flat lower surface 35, two side surfaces 53 and 54, and preferably a V-shape. The slide valve 33 formed by the block consisting of two end faces 55 and 56 including () and (39b) is essentially received. However, this form is not essential and may vary in any embodiment.

It can be seen that the balls 28 and 30 are engaged with the above grooves and guarantee the centering action of the slide valve.

Transverse conduit 36 has a rectangular shape or substantially rectangular cross section and occupies a pseudo-central position in the illustrated embodiment.

FIG. 3 shows a perspective view of the compression spring 40 which enjoys the upper surface of the corresponding slide valve 33 and the annular element 41 mounted to the body 12 below the block 15.

In practice, the metering device is operated in the following manner: The material to be metered is supplied to the inlet 13 by a suitable device (not shown), for example a conduit connected to the reservoir. This material enters the seal 45 formed inside the central cavity 18 through the communication passage 42. This material then flows towards one of the transverse ducts 38 by passing through the transverse conduit 36 of the movable slide valve. Since the duct 38 exits the outlet 14, the flow of metered material is freely taken up by the conduits above.

The position of the movable slide valve is very precisely defined by the pusher controlled by the drive and the return spring exerting an opposite pressure on the slide valve.

4a, 4b and 4c illustrate the operation of such a device. In FIG. 4A the slide valve 33 is at rest and the metering valve is closed. The transverse conduit 36 is sealed by a fixed plate 37. Likewise, the grooves 39a and 39b are sealed at their bottom by a fixed plate 37. The transverse duct 38 of the fixed plate 37 is sealed by the flat lower surface of the slide valve.

In the position shown in FIG. 4B, the slide valve is pushed back slightly and the point 60 of the groove 39a partially covers one of the transverse ducts 38, allowing a moderate flow of material. Similarly, some overlap 61 is observed between the cross duct 36 and the cross duct 38 of the fixed plate 37. In this position, stable metering is ensured. In the position shown in FIG. 4C, the overlap described earlier is more complete, which allows for faster flow and thus greater metering.

Displacement of the movable slide valve occurs without play. The friction against the fixed part of the slide valve, ie the plate 37, which is in fact the only movable part of the actual metering valve, is the friction between the polished flat surfaces without any play and thus without leakage. For this reason, the wear of this element can be neglected, and the life of the metering valve and consequently the life of the whole metering device is greatly increased compared to known systems. In addition, the number of parts constituting the device is relatively small and their machining is completely conventional. Preferably the slide valve and the fixed plate can be made of ceramic material and thus make it possible to have a good seal and very little wear between the two surfaces in contact.

The present invention is not limited to the described embodiments, and various modifications are possible and can be represented in various different forms apparent to those skilled in the art. In particular, the shape and dimensions of the mechanical elements controlling the displacement of the movable slide valve can be varied. Further, the shape of the block constituting the movable slide valve may vary to some extent as long as the presence of the flat upper surface 34, the lower surface 35 and the lower surface of the conduit 36 is preserved.

In particular it will be possible to simplify the structure of the pusher with respect to the seal. It is possible that the material to be metered fills the entire cavity 18 and simply ensures a seal with respect to the outside. Such a structure not only reduces manufacturing costs, but also reduces the cost of maintaining such a device.

Claims (12)

The body 12 of the metering valve 11, the inlet 13 for the material to be metered, the outlet 14 for the metered material and the inlet 13 and the outlet 14 inside the body 12. In a micrometering device comprising a metering valve 11 mounted between the heads and which can be opened or closed, the metering valve 11 has a flat surface and the outlet 14 for the metered material. And a slide valve (33) having a fixed plate (37) equipped with at least one duct (38) communicating therewith and a flat surface (35) arranged to lean on said flat surface of the fixed plate (37). The slide valve 33 allows the flow of material to be metered towards the duct 38 above of the stationary plate when the valve is in one of the positions corresponding to the opening of the metering valve 11 and the shutoff of the valve. This flow when in one of the corresponding positions At least one passage means (39a, 39b, 36) arranged to stop, and said passage means of the slide valve (33) is one of the outer end surfaces (55, 56) in the sliding direction of this slide valve. And a groove (39a, 39b) having at least one shape formed in at least one and connecting said flat surface (35) with said opposite surface (34). 2. The micrometric measuring device according to claim 1, wherein the grooves (39a, 39b) having the shape have a cross section in the form of at least approximately V. 2. The passage according to claim 1, wherein said passage of the slide valve (33) is on the one hand to communicate with said inlet (13) for the material to be measured over shaped grooves (39a, 39b). And 35), on the other hand, at least one transverse conduit (36) on the opposite side (34) of the slide valve. 4. The slide valve (33) according to claim 2 or 3, wherein the slide valve (33) is a lower surface (35) consisting of the flat surface that rests on the flat surface of the fixed plate (37), and an opposite side of the lower surface. By a block comprising two end faces 55, 56, each comprising an upper face 34, two lateral faces 53, 54 and recesses 39 a, 39 b having a generally V-shaped cross section. The micrometric measuring device which is comprised. 2. The slide valve (33) according to claim 1, characterized in that the slide valve (33) is combined with a drive device (22) arranged to linearly transport it in one direction and a return spring (24) arranged to linearly transport it in the opposite direction. Micrometering device. 6. The block as claimed in claim 5, wherein the block constituting the slide valve (33) is mounted in a central cavity (52) formed in the longitudinal pushers (21, 23), the pusher (22). And a second end (29) supported relative to said feedback spring (24). 7. The micrometric measuring device according to claim 6, wherein the driving device (22) is an electric or pneumatic or hydraulic or electromechanical device. 7. The block as claimed in claim 6, wherein the block constituting the slide valve (33) is engaged with two centering balls (28) engaged with grooves (39a, 39b) each having a shape formed on the end faces (55, 56) of the block. , 30 is a micrometer measuring device, characterized in that mounted to the central cavity (52). 5. The device of claim 4, wherein the device comprises a compression spring (40) arranged to apply pressure on the flat upper surface (34) of the block (33). 10. The bearing ring (41) according to claim 9, wherein the compression spring (40) comprises a bearing ring (41) comprising a surface arranged to contact the upper surface (34) of the block forming the slide valve (33). A micrometer measuring device, characterized in that it is mounted between elements having at least one passageway (42) for communicating with said inlet (13). 12. The measuring device according to claim 10, wherein said bearing ring (41) comprises at least one connecting nipple arranged to engage a transverse conduit (36) of said slide valve (33). A side metering device according to claim 1, characterized in that the slide valve (33) and the fixed plate (37) are made of a ceramic material.