EP0700358A1

EP0700358A1 - Single pipe - two-way distributor

Info

Publication number: EP0700358A1
Application number: EP95914326A
Authority: EP
Inventors: Wolfgang Rumpf; Georg Stapp; Paul Gerhard Dellmann; Harald Friedrich
Original assignee: Reimelt Dietrich KG
Current assignee: Reimelt Dietrich KG
Priority date: 1994-04-02
Filing date: 1995-03-29
Publication date: 1996-03-13
Also published as: DE4411529C2; WO1995026921A1; DE4411529A1

Abstract

The invention concerns a single pipe - two-way distributor (1) with a housing (2) comprising a plug chamber (4) into which open a first connection duct (5), a second connection duct (6) and a third connection duct (7), and in which a plug (3) comprising a flow duct (14) is rotatably disposed. In a distributor of this type, the characteristic curve of the flow can be configured largely independently of the position of the plug and/or of the through-flow direction. To this end, the first, second and third connection ducts (5, 6, 7) open out radially into the plug chamber (4). A first peripheral angle between the first connection duct (5) and the second connection duct (6) is equal to a second peripheral angle between the first connection duct (5) and the third connection duct (7), and a third peripheral angle between the ends (19, 20) of the flow duct (14) is equal to the first and second peripheral angles.

Description

Single pipe two-way distributor

The invention relates to a single-pipe, two-way distributor with a housing which has a plug chamber into which a first connection duct, a second connection duct and a third connection duct open and in which a plug, which has a flow duct, is rotatably arranged, the first , the second and the third connecting channel open radially into the plug chamber, a first circumferential angle between the first connecting channel and the second connecting channel is equal to a second circumferential angle between the first connecting channel and the third connecting channel, a third circumferential angle between the ends of the flow channel is the same as the first and the second circumferential angle and the flow channel and the connection channels are provided with the same cross section.

Such distributors are widely used in systems for the pneumatic conveying of bulk material in order to control the flow path of the bulk material. In a first position, the chick's flow channel connects the first connection channel with the second connection channel. After the plug has been rotated by a predetermined angle, the flow channel connects the first connection channel to the third connection channel. Such distributors are also referred to as pipe switches or rotary valves.

Pipe switches also exist in an embodiment with two flow channels, the first flow channel being responsible for the connection between the first and the second connection channel and the second flow channel being responsible for the connection between the first and the third connection channel. Such two-pipe distributors can indeed be designed with regard to the flow characteristics in such a way that the differences in flow behavior between the two different positions of the plug can be kept relatively small. In addition, the plug only has to be pivoted through a smaller angle, so that a correspondingly simpler drive is required. Because of the necessity of two flow channels, such a pipe switch, however, requires a considerable size.

In the case of one-pipe two-way distributors, on the other hand, the problem frequently arises that the flow characteristic is very different in the two positions of the plug. In many cases the problem also arises that the flow characteristic depends on the direction of flow, which is particularly disadvantageous if the bulk material is to be both blown through and sucked through in a pipe system which is equipped with such a pipe switch.

A number of proposals have already been made to solve the problem. This is how DE describes it

41 14 949 Cl a chick with a free-form surface that essentially corresponds to a spherical surface. This Chick is pivoted about an axis that is parallel to the plane in which the connecting channels are located. In this case, however, a considerable amount of processing work is required to shape the plug.

DE 40 09 218 AI shows a rotary slide switch in which an adapter ring is provided in order to avoid shocks during the transition from the connecting ducts into the flow duct, which can be rotated both with respect to the housing and with respect to the plug. An additional component is required here, which complicates the structure and makes the production correspondingly expensive.

Another pipe switch is known from DE 39 40 668 Cl. The plug has a flow channel that connects the first connection channel to the second connection channel in a first position, and an impact surface that forms a boundary surface of the plug room in a second position, which in this case forms the first connection channel with the third connection channel connects.

Furthermore, from DE 39 15 125 AI a rotary slide switch is known in which the connecting channels are offset eccentrically to the central axis and the flow channel is also offset by the same eccentricity with respect to the center point. Even with such a configuration, the differences in the flow characteristics can only be reduced to a limited extent. In particular, as with most pipe switches, this results in an enlarged cross-sectional area in the branch from the housing to the plug in the branch position compared to the pipe cross section.

DE-AS 12 18 827 shows a single-pipe two-way distributor of the type mentioned at the outset, which is particularly suitable for is used in concrete delivery lines or blow-off lines.

A similar pipe switch is also known from DE-OS 21 48 577. Here the flow channel is formed by a pipe which has an arcuate section to which two straight pipe sections are attached. The straight pipe sections open radially into the outer circumference of the plug.

DE-PS 511 267 describes a reusable valve for hydraulic systems, in which a plug with a curved tubular flow path can either connect two of three connecting pieces to one another or shut off all three connections. The three connections open radially into the chick room. As with the previously discussed documents, they are designed as straight pipe sockets.

The three last-mentioned distributors offer the same flow characteristics regardless of the plug position because they are constructed symmetrically to a plane that passes through the central axis of the one connecting piece and the axis of rotation of the plug. However, this has the disadvantage that such a distributor can often not be retrofitted in existing systems, or only at relatively great expense. Branches can often be found here, in which a branch pipe branches off from an essentially straight pipe run at an angle of 35 ° or 45 °. With the known three distributors, a relatively complicated additional fitting for the individual connections would be necessary, which allows the distributor to be used in existing systems. However, it is easily conceivable that such a fitting will again adversely affect the flow characteristics in the individual directions and, moreover, will require a considerable amount of space. The object of the invention is to make the flow characteristic largely independent of the position of the plug and / or the flow direction, even in the case of a distributor which is suitable for branching off from an essentially straight line line.

This object is achieved in a single-pipe, two-way distributor according to the preamble of claim 1 in that at least one of the connecting channels has an arcuate shape between a connecting flange and its mouth into the plug chamber.

As a result, the flow characteristic is designed independently of the position of the plug. Despite an asymmetrical branch, the structure of the distributor is largely symmetrical with regard to the connection channels or their mouth into the plug room. The flow behavior practically does not change if the direction of flow is changed. The term "radial mouth" can basically only be applied to a linear connecting channel. In the case of a real channel that has a finite extent, the term “radial opening” therefore refers to the central axis of the channel. To change the flow path, the plug is rotated through an angle which corresponds to the circumferential angle. Then, as is also known with other such rotary valves, the end of the flow channel, which was connected to the second connection channel, coincides with the first connection channel, while the other end of the flow channel, which was previously aligned with the first connection channel , is now brought into overlap with the third connection channel. Due to the equality of the angles, the flow behavior through the distributor does not change in this embodiment. The branch angle can be kept relatively small. Thanks to the In the course of at least one of the connecting channels between a connecting flange and its mouth into the plug area, the distributor can be designed so that its connecting pieces have the same orientation as that of conventional distributors, pipe switches or

Rotary slide switch is known, namely with parallel or on a line or axis connecting flanges on the first and second connecting channels and with a connecting flange angled at 45 ° or 35 ° or even a smaller angle on the third connecting channel. The arch shape of at least one connection channel nevertheless allows all connection channels to open radially into the plug area and to keep the necessary external dimensions small.

In a preferred embodiment it is provided that the ends of the flow channel are aligned radially. In this case there is a transition from the housing to the chick, i.e. no change in cross-section from the connecting channels into the flow channel and therefore no impact. These bumps were perceived as bothersome and uncomfortable. They place a considerable load on the conveyor system. Some funding procedures only work satisfactorily if impacts are avoided. With such a configuration, the flow channel and the connecting channels can be provided with the same cross section. The transition between the connecting channels and the flow channel then takes place over a smooth surface which is only interrupted by a small gap between the plug and the housing, but not by a kink or any other geometric shape.

The walls of the flow channel and the connecting channels preferably run parallel to a central axis, at least in the region of the transition between plug and housing. This can be used to ensure that no cross-sectional change occurred during the transition. The plug or the flow channel can be flowed through in the same way as the rest of the pipeline.

The flow channel preferably runs in the form of an arc from one end to the other. The connection of the first and third connection channels results in a significantly lower flow resistance. The choice of an arc in turn avoids kinks and edges, so that the flow channel does not build up any appreciable flow resistance despite a change in direction.

The arc is preferably part of a circle. Here, too, this configuration basically only applies to a linen-shaped channel. In the case of a flow channel with a finite extent, this statement applies only to the central axis, which runs in the form of an arc of a circle. The curvature is constant in a circular arc. This keeps the flow resistance low. There is little, if any, turbulence that leads to an increase in flow resistance. In most cases, however, the flow channel can flow through practically as smoothly as a straight piece of pipe.

The first, second and third circumferential angles preferably have a size of 150 ° and the first and second connecting channels form an arc over an angle of 15 ° between their connecting flange and their mouth. With this configuration, extremely favorable flow values are achieved. On the other hand, a 45 ° branch for the third channel can be realized in a simple manner, which branch is connected to the first connection channel by switching the plug by 150 °. In a preferred embodiment, the plug has a carrier in which a tube is installed as a flow channel. In this case the tube can be made relatively thin-walled. The mechanical support function is carried out by the wearer. This configuration allows a relatively simple and therefore inexpensive construction.

In this case, it is preferred that a sealing device is provided in the housing for each connection channel, which cooperates with the carrier. This embodiment shows the advantage that the radial opening of the flow channel offers. When the plug moves, the seals are only run over by an edge that has an angle close to 90 °.

As a result, the wear of the seals is kept small.

In a further preferred embodiment, the plug is formed by a tube having the flow channel. Of course, this tube must be stored in some way, for example with the help of one or two lids. The support function by a carrier is omitted here. Nevertheless, a relatively lightweight chick can also be realized with this configuration. The tube can be cast, for example.

The tube preferably has a tube wall thickening at its ends. This thickening of the tube wall leads to a correspondingly enlarged area, which leads to an improved seal between the plug and the housing in the region of the ends of the flow channel.

It is preferred that the tube has a sealing arrangement at each end, which cooperates with the housing. If the sealing arrangement is not arranged in the housing but in the plug, one does not need more three sealing arrangements for three connecting channels, but only two sealing arrangements for the ends of the flow channel. This reduces the effort. Since all the connecting channels open radially into the plug area, each sealing arrangement is only exposed to edges when the plug moves which form an angle in the range of 90 °. This angle is "obtuse" in all cases, so that the sealing arrangement is not significantly stressed here.

The invention is described below on the basis of preferred exemplary embodiments in conjunction with the drawing. Show here:

1 shows a first embodiment of a distributor with a first position of its plug,

2 shows the embodiment of FIG. 1 with the chick in its second position,

3 is a sketch for explaining geometric sizes,

Fig. 4 shows a second embodiment of the distributor with the chick in its first position and

Fig. 5 shows the second embodiment of the distributor with the chick in its second position.

A tube switch 1 designed as a one-pipe, two-way distributor has a housing 2 and a plug 3, which is rotatably mounted in a plug chamber 4. The chick room 4 has a circular cross section. A flow channel 14 is provided in the plug 3.

In the housing 2 there is a first connection channel 5, a second connection channel 6 and a third connection channel 7 intended. Each connection channel has an imaginary axis or center line 8, 9, 10. The first connecting channel 5 has a connecting flange 11, the second connecting channel 6 has a connecting flange 12 and the third connecting channel 7 has a connecting flange 13. All three connecting channels 5, 6, 7 open radially into the plug space 4. For a tubular connecting channel Strictly speaking, parallel walls, as used here, only apply if the channel is linear, ie has no extension. As soon as the channel has a finite extent, not all parts of the channel are exactly radial. For the present invention, the term "radially opening" therefore means that the axes 8, 9, 10 are perpendicular to the tangent 15 to the plug 3 in the transition between the connecting channel and

Flow channel 14 is. This is shown as an example for the second connecting channel 6. Another possible definition is that a perpendicular perpendicular 16 to a secant 17, which is delimited by the walls of the connecting channel, runs through the center M of the plug 3 and the plug chamber 4. This is shown by way of example for the third connection channel 7 in FIG. 2.

The first connection channel 5 is in the circumferential direction from the second connection channel 6 as far as from the third connection channel 7. This distance is at a circumferential angle a between the first connection channel 5 and the second connection channel 6 or a circumferential angle b between the first connection channel 5 and the third Connection channel 7 shown. Here a = b applies. In the illustrated embodiment, a = b = 150 °.

The flow channel 14 has two ends 19, 20 which are separated from one another by the same circumferential angle. The flow channel 14 also opens radially at its ends 19, 20, ie the center line 18 at the ends 19, 20 is perpendicular to the tangent at the transition point. The flow channel is curved in an arcuate manner between the two ends 19, 20. The center line 18 forms part of a circular line. If the flow channel 14 has a circular cross section, the flow channel 14 thus forms part of a torus.

In the housing 2, a sealing arrangement 21, 22, 23 is provided for each connecting channel 5, 6, 7, which acts on the peripheral surface of the plug 3. The plug has a carrier 24 in which a bent tube 25 is inserted.

The first connecting channel 5 and the second connecting channel 6 are also curved in an arcuate manner between their connecting flange 11, 12 and their mouth into the plug chamber 4. The arc angle is 15 ° in both cases.

The geometrical dimensions are shown in FIG. 3. Here, the pipe switch 1 is shown schematically. The flow channel 14 is shown in the position according to FIG. 1 with solid lines. The flow channel 14 is shown in the position according to FIG. 2 with an interrupted line. In addition to the circumferential angles a, b, the arc angles c, d can be seen here, by means of which the first and the second connecting channels 5, 6 are curved. In the present exemplary embodiment, c = d = 15 °.

Due to the circular shape of the plug, the circumferential angles a, b correspond to counter angles e, f, which in the present case are e = f = 30 °. By rotating the plug by the circumferential angle a = b = 150 °, the flow channel 14 is therefore brought into a position (FIG. 2) that deviates 45 ° from the first position according to FIG. 1. In Fig. 3, the connecting channels 5, 6, 7 and the flow channel 14 (1) and 14 (2) are shown in a line. However, since the channels have a certain diameter, an additional explanation is necessary for the dimensioning of the angles. The nominal diameter 40 of the first connection channel 5 is exaggerated. The opening cross section is therefore on one secant in the housing. The same applies to the other connection channels 6 and 7. An inscribed circle which affects all secants defines at the points of contact with the

Secants are the points between which the angles a - f are to be measured.

It can be clearly seen that, despite the curved shape of the flow path according to FIGS. 1 and 2, a smooth transition from the connection channels 1, 2 and 3 to the flow channel 14 is possible, i.e. there is no change in cross-section during the transition. Despite the arch shape of the flow channel 14, there is always a freely flowable cross section available. Due to the arc shape of the flow channel 14 and the first and second connection channels 5, 6, there is also no appreciably increased flow resistance.

The chick has essentially changed in the embodiment according to FIGS. 4 and 5. The chick now has, apart from fastening parts not shown in detail, only a tube 26 with thickened wall sections 27 at the ends. A sealing arrangement 28, 29 is provided for each end, which interacts with the housing 3 on the boundary wall 30 of the plug chamber 4. In this case, only two sealing arrangements are necessary and no longer three, as in the embodiment according to FIGS. 1 and 2. In addition, this arrangement has the advantage that the sealing arrangements 28, 29 only have to sweep over edges that form an obtuse angle , because the connection channels 5, 6, 7 all open radially into the chick room 4. The remaining parts correspond to those of FIGS. 1 and 2 and are therefore provided with the same reference numerals.

1 and 2, the connecting channels 5, 6, 7 are formed by tubes or tube sections 31, 32, 33 which are inserted into the housing, the connecting channels 5, 6, 7 are in the Ausge¬ 4 and 5 formed by housing sections 34, 35, 36, which can be produced for example together with the housing 2 'by casting. The plug 3 'can also be designed as a cast part.

Claims

claims

1. One-pipe, two-way distributor with a housing which has a plug chamber into which a first connection duct, a second connection duct and a third connection duct open and in which a plug which has a flow duct is rotatably arranged, wherein the first, the second and the third connecting channel open radially into the plug chamber, a first circumferential angle between the first connecting channel and the second connecting channel is equal to a second circumferential angle between the first connecting channel and the third connecting channel, a third circumferential angle between the ends of the flow channel is equal to the first and the second circumferential angle and the flow channel and the connection channels are provided with the same cross-section, characterized in that at least one of the connection channels (5, 6, 7) between a connection flange ( 11, 12, 13) and its mouth into the chick room (4) has an arcuate course.

2. Distributor according to claim 1, characterized in that the ends (19, 20) of the flow channel (14) are radially aligned. 3. Distributor according to claim 2, characterized in that the walls of the flow channel (14) and the An¬ connection channels (5, 6, 7) at least in the region of the transition between chicks (3,

3 ') and housing (2, 2') run parallel to a central axis (8, 9, 10, 18).

4. Distributor according to claim 2 or 3, characterized gekenn¬ characterized in that the flow channel (14) runs in the form of an arc from one end (19) to the other (20).

5. Distributor according to claim 4, characterized in that the arc is part of a circle.

6. Distributor according to one of claims 1 to 5, da¬ characterized in that the first, second and third circumferential angle (a, b) has a size of 150 ° and the first and second connecting channel (5, 6) between their connecting flange ( 11, 12) and their mouth form an arc over an angle of 15 °.

7. Distributor according to one of claims 1 to 6, characterized in that the plug (3) has a carrier (24) in which a tube (25) is installed as a flow channel (14).

8. Distributor according to claim 7, characterized in that in the housing (2) for each connection channel (5, 6,

7) a sealing device (21, 22, 23) is provided which interacts with the carrier (24).

9. Distributor according to one of claims 1 to 6, characterized in that the plug is formed by a tube (26) having the flow channel (14).

10. Distributor according to claim 9, characterized in that the tube (26) has a tube wall thickening (27) at its ends.

11. Distributor according to one of claims 7, 9 or 10, characterized in that the tube (26) has a sealing arrangement (28, 29) at each end, which cooperates with the housing (2 ').