JPH0317285B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a metering unit for installation in the external housing of a flow meter for fluids, in particular a domestic water meter. Here, the housing is provided with a seating surface and inlet and outlet openings for the measuring unit.

BACKGROUND OF THE INVENTION A standard domestic water meter has a housing closed at the top by a closure ring, both the housing and closure ring being made of brass. These brass parts not only last a long time, but also account for more than 50% of the water meter's cost in terms of manufacturing costs. For this reason, water supply companies have adopted the philosophy of using water meter housings for as long as possible and only replacing parts that are subject to wear and tear, such as recording indicators, impellers, and impeller housings, as necessary. However, this way of thinking has been hampered by the following problems. Modern commercially available measuring units are, in principle, not interchangeable with the external housings of older water meters. In recent years, inexpensive and strongly built impellers have become popular (speed measurement principle). However, it is impossible to take out the impeller measuring unit and convert it into another type of water meter unit, especially a so-called rotary piston meter (volume measuring principle), even if the impeller measuring unit can be inserted and fitted into the external housing of an existing water meter. It was possible.
This is because it has been impossible to calibrate such water meters assembled from conventional components. Even the manufacturer who made the meter is often unable to replace the measuring unit of an old water meter. Furthermore, even if it were possible, the cost of replacing it may not be economically worth it. The original manufacturer often does not arrange for parts to be handed over to competitors.

Problems to be Solved by the Invention The object to be achieved by the invention is to provide a universal impeller measuring unit, which is as close as possible to the inner diameter of the outer housing of a flow meter for fluids sold on the market. It can be adapted inexpensively and the impeller measuring unit is preferably of what is called an ultra-dry water meter, the impeller and impeller housing being immersed in the liquid flow, however the impeller housing is completely dry. It operates under certain conditions. Measuring units of this type are known per se and include an impeller housing which houses an impeller and an indicating mechanism. The pointing mechanism is disposed on the impeller housing and is adapted to be driven by the impeller via a magnetic coupling. In addition to this, the metrological properties of the measuring unit are unaffected, or as little as possible, by differences in the outer housing of the meter.

Means for solving the problem This objective is achieved by the following measuring unit: That is, the measurement unit includes an impeller housing for housing the impeller, and the impeller housing includes a plurality of inlet openings arranged in parallel in the circumferential direction, and a plurality of inlet openings arranged in parallel in the circumferential direction at a distance from the inlet openings in the axial direction. a recording mechanism is disposed within the impeller housing, the recording mechanism being driven by the impeller via a magnetic coupling;
The recording mechanism is mounted in the outer housing of a liquid water meter, in particular a domestic water meter, the outer housing being provided with a seat for the measuring unit and inlet and outlet openings.

According to the invention, a sleeve-like adapter ring is provided, the impeller housing being arranged within the sleeve-like adapter ring, the adapter ring having a sleeve part with a closed circumferential wall, the circumferential wall connecting the inlet opening of the impeller housing to the sleeve part. radially spaced apart from and surrounding the adapter ring, on the outside thereof a counterseat for insertion into a seat on the outer housing, and on the inside thereof for a counterseat on the impeller housing. It is characterized by forming the seat of Based on the radial dimension of the counter seat provided on the outside of the adapter ring and on the basis of the axial alignment of said counter seat with respect to the seat of the impeller housing provided on the inside of the adapter ring, the measuring unit is placed in the seat of the outer housing. Not only can it be provided, but also the measuring unit can be in the correct axial position within the outer housing. Furthermore, the adapter ring can be made very inexpensively, in particular as an injection molded part of plastic. The impeller housing is a standard type, and the same tools and bits can be used to form the inside of the adapter ring. Different tools or bits are required only for shaping the outside of the adapter ring. This is because it is the outside of the outer housing that must be fitted into the outer housing in use.

The measurement characteristics of an impeller meter are highly dependent on the way the fluid flows relative to the inlet opening of the impeller housing. The sleeve portion of the adapter ring surrounding the inlet opening in identical radially spaced relation ensures that different internal dimensions and configurations of the various outer housings have a negligible effect on the metrological characteristics of the measuring unit. . The adapter ring is thus in the form of an axially extending apron in at least the part of the impeller housing where the inlet opening is located.

The configuration of the flow path between the impeller housing outlet opening and the outer housing outlet opening has a small influence on the metrology characteristics. Therefore, the adapter ring preferably surrounds the outlet opening of the impeller housing at a distance therefrom.

In the case of impeller water meters, what is known hitherto (German Published Patent Application No. 100 162) is that the measuring unit with an impeller housing is arranged in an annular shape on the inner wall of the support sleeve by means of an outer flange arranged on the impeller housing. It is placed on a seat located within the shoulder. The support sleeve itself is supported in a seat in the bottom of the outer housing of the water meter. However, in this construction neither the outer flange nor the support sleeve can serve the purpose of the adapter element, and the support sleeve does not serve the purpose of shielding the inlet or outlet opening of the impeller housing. In contrast, the support sleeve has inlet and outlet openings corresponding to the inlet and outlet openings of the impeller housing, which inlet and outlet openings are located at the same height as the corresponding openings of the impeller housing. . Additionally, the impeller housing extends upwardly and houses a resistor, which is driven directly by the impeller shaft projecting therefrom.

The sleeve-shaped adapter ring configured according to the present invention forms an annular gap with the impeller housing, into which fluid flows in the axial direction. A support sleeve of known construction, on the other hand, seats tightly against the bottom of the outer housing through which fluid flows in a generally radial direction.

When the part of the measuring unit arranged on the impeller housing projects axially beyond the circumferential wall of the impeller housing, the adapter ring forms an outflow opening with respect to the other part of the measuring unit, so that the impeller housing It must be noted that the exiting liquid can flow through the gap between the impeller housing and the adapter ring. In a preferred embodiment of the measuring unit according to the invention, the impeller housing is cup-shaped and is closed by a cover. In this case, it is recommended that the adapter ring has the following structure. That is, the adapter ring terminates at an axial distance from the cover to form an outflow opening as described above.

According to a preferred embodiment, the cup-shaped impeller housing is closed by the bottom of a cup-shaped recorder housing, into which the recording mechanism is inserted. The two parts of the magnetic coupling that drive the recording mechanism are located on opposite sides of the bottom of a cup-shaped housing made of plastic, brass, or the like. This cup-shaped recorder housing is aligned with the impeller housing. Alternatively or additionally, the cup-shaped housing can be aligned with the outer housing. In a preferred embodiment, a centering ring is provided around the cup-shaped recorder housing, allowing the measurement unit to be compatible with a variety of outer housings. This centering ring abuts the inside of the outer housing. Adjustment of the fit can therefore be effected solely by the centering ring, which is made as a very simple component and is fixed axially by the outer shoulder of the cup-shaped recorder housing.

The impeller housing has a number of circumferentially extending inlet openings and a number of circumferentially extending outlet openings spaced axially from the inlet openings so that calibration of the measuring unit can be easily carried out at this point prior to installation. It is recommended that the sealing member is provided between the impeller housing and the adapter ring and between the inlet and outlet openings of the impeller housing in the axial direction. These seal members form a bypass opening whose flow cross section is variable by rotating the adapter ring relative to the impeller housing. It is possible to configure the sealing member so that the bypass opening is completely closed. The simplest way to achieve this is to provide annular shoulders on the seat on the inside of the adapter ring and on the counter seat on the outside of the impeller housing, with the annular shoulders abutting each other and each having at least one opening. can be made to form. These apertures can be made more or less aligned with each other by rotating the adapter ring relative to the impeller housing. In accordance with the present invention, the variable bypass opening can be combined with an apron-forming feature that optionally also shields the inlet and outlet openings of the impeller housing. This allows the measuring unit to be adjusted by the manufacturer and only subsequently needs to be inserted into the outer housing of an already inserted flowmeter.

It is recommended that a damping or blocking device be provided between the adapter ring and the impeller housing, so that the adapter ring and the impeller housing cannot inadvertently change the internal cross-section of the bypass opening with respect to each other. The simplest way to achieve such an arrangement is to provide a first annular shoulder with teeth and a second annular shoulder with a notch that engages the teeth. At least one of the two locking members is resiliently biasable. This is very easy if the adapter ring and/or the impeller housing are made of plastic parts.

Finally, mold the adapter ring into a cup shape.
Preferably, a strainer is formed at its bottom to prevent coarse dust from going to the impeller. In order to keep the components fitted to the outer housing as simple as possible, in a preferred embodiment they can be mounted as a separate perforated bottom to the bottom of the impeller housing.

Embodiment The dash-dotted line in FIG. 1 shows a housing 10 of a commercially available ordinary household water meter. The housing 10 includes a closure ring 12 and a hinged lid 14 that are screwed into the housing. The outer housing 10 has a pair of threaded connecting pipes 20 and 22 made of steel.
and 22 form the inlet opening 16 and the outlet opening 18. The outer housing further has a partition wall 26;
This partition wall 26 includes a mounting hole 24 and divides the outer housing 10 into an inlet chamber 28 and an outlet chamber 30 as well as a neck 32 . The neck 32 is a cylindrical inner wall 3
4 and an external thread into which the closure ring is screwed. The mounting opening 24 together with the surrounding upper edge 40 forms a seat 42 for the measuring unit 44 of the invention.

The essential elements of the measuring unit 40 are an impeller housing 46, an impeller 48 rotatably mounted on the impeller housing 46, an adapter ring 50 surrounding the impeller housing, and a steel ring 50 that closes the impeller housing at its top. It consists of a cup-shaped recording mechanism housing 52 and a recording mechanism 54 inserted into the cup-shaped housing. The adapter ring 50 is made of plastic injection molding and has an annular shoulder on its outer side forming a counterseat 56 and a collar 60 on its inner side.
Seat 58 and upper and lower aprons 62 and 64
A counter seat 56 is located between these aprons. Preferably, the insides of these two aprons are strictly circular cylinders.

The impeller housing 46, which is made by injection molding of plastic, has a ring-shaped inlet opening 68 in the lower part of its peripheral wall 66.
A ring-shaped outlet opening 70 is provided at the top of the holder. A pin 74 is formed in the bottom 72 of the cup-shaped impeller housing. The bottom 76 of the generally cup-shaped adapter ring 50 serves as a strainer and is mounted on the pin 74. As will be explained later, this structure is advantageous in the following points. That is, different outer housings 10 require different adapter rings 50, while the plastic injection molded bottom 76 can be the same. Continuous shoulder 80
are molded on the outside of the impeller housing peripheral wall 66 to form a counter seat 82. The impeller housing together with this opposing seat is the seat 5 of the adapter ring 50.
Inserted for 8. The lower apron 62 extends downwardly beyond the impeller housing 46 such that the bottom portion 76 overlaps the bottom 72 of the impeller housing.
axially far enough away from lower apron 6
The inner diameter of impeller 2 is larger than the outer diameter of impeller housing 46 in the region of inlet opening 68 and is chosen in such a way that the flow rate to impeller 48 is optimized. Similarly, the inner diameter of the upper apron 64 is greater than the outer diameter of the impeller housing 46 in the region of the outlet opening 70, such that the upper apron 64 extends slightly beyond the upper edge of the outlet opening 70 in the upward direction. In combination with this configuration, the flow velocity is selected to be the optimum value.

Shoulder 60 cooperates with shoulder 80 of the impeller housing such that when bypass opening 90 is closed, all water flowing through perforated bottom plate 76 flows into the chamber containing impeller 48. Bypass opening 90 is defined by a recess 92 formed in shoulder 60 and a recess 94 in shoulder 80 that allow rotation of adapter ring 50 relative to impeller housing 46 . The overlap can be varied in size and can even be offset from each other so that the bypass opening 90 is completely closed (FIG. 2). To prevent adapter ring 50 and impeller housing 46 from inadvertently rotating relative to each other, shoulder 80 has teeth 96 along a portion of its circumference.
, the teeth 96 of which cooperate with indentations 98 formed in the inner wall of the adapter ring 50 above the radially aligned surface of the seat 58. adapter ring 5
0 and the impeller housing 46 are both plastic parts and are capable of slight elastic deformation, so the adapter ring 50 can be carefully rotated relative to the impeller housing 46, thereby opening the bypass opening 90. The size can be adjusted.

Shinchiyu cup-shaped recording mechanism housing 52
is fitted onto the impeller housing 46, with its bottom 100 penetrating the impeller housing 46 slightly, thereby centering the two parts relative to each other. A pin 102 is fixed to the bottom 100 and projects into the impeller housing 46. Impeller 48 is rotatably mounted to pivot pin 102. The impeller is made of a relatively lightweight plastic material so that it floats during stop and start until the impeller is rotated by the bearing surface on the pivot pin 102. As the flow through the impeller housing 46 increases, a turbulence is induced, which turbulence occurs at the point 1 of engagement on the bearing surface of the bottom 72 of the impeller housing.
The impeller housing can be moved relative to 04.
Finally, the impeller 48 carries one half of the magnetic coupling 106, and the other half of the coupling carries the recording mechanism 5.
4, but not shown. This recording mechanism may be a known component, for example a cipher roll type recording mechanism, and no further detailed description is deemed necessary. Alternatively, it may be a recording mechanism capable of electrically recording measured values and transmitting data. The recording mechanism 54 includes a molded boss 108 on the mechanism and a cup-shaped housing 52.
It is centered within the cup-shaped housing 52 by a recess 110 in the bottom 100 of the cup.

The housing 52 has an annular shoulder 112 around its periphery, which serves as a seat for a centering ring 114. With this centering ring 114 the cup-shaped housing 52 is attached to the neck 3 of the outer housing 10.
The core is aligned with 2. This centering ring is made of inexpensive plastic material, thereby eliminating the need for fitting the cup-shaped housing 52 to the outer housing 10. That is centering ring 11
This is because it is sufficient that the outer diameter of 4 is adjusted to the inner diameter of the neck 32 of the outer housing.

According to another feature of the invention, the sealing member 118 is connected to the retaining ring 116, the neck 32 and the centering ring 11.
4 and the recording mechanism housing 52. The outer diameter and height of the ring 116 are the same as the housing 10.
and the structure of the closure ring 12, the outflow chamber 30 of the outer housing 10 is adapted to the structure of the closure ring 12.
2 is screwed into the outer housing 10 so that it is easily sealed at the top. Another sealing member 120 is positioned between the recording mechanism 54 and the annular shoulder 122 of the retaining ring 116.

The invention achieves the objectives specified at the outset in a simple manner. That is, the outer diameter of the adapter ring 50, the outer diameter of the centering ring 114, the height, and the sealing member 118.
furthermore, only the outer diameter and height of the retaining ring 116 in the outer housing 10 or the closure ring 1.
2, since this does not affect the basic elements of the metering unit 44 or the inflow and outflow volumes to and from the impeller housing.

As described above, in this invention, the measurement unit 4
4 is seated inside, and an adapter ring 50 is provided which is inserted and seated externally into the opening 24 formed in the partition wall 26 of the housing, and the outer apron 62 of the adapter ring 50 is connected to the inlet opening 68 of the measuring unit 44. By extending along the circumferential wall of the adapter, the apron 62 eliminates the tendency for the fluid to be measured to flow directly into the inlet opening 68, and allows the fluid to pass between the apron of the adapter and the outer periphery of the impeller housing. The flow resistance imparted to the liquid flow at the point of the metering unit 44 is always the same regardless of the shape of the housing, and the metering unit of the present invention can be installed in any commercially available housing of any size. Regardless of the size of the housing, the difference in dimensions of the housing can be absorbed and accurate measurement can be performed at all times.

[Brief explanation of the drawing]

Fig. 1 is an axial sectional view of the outer housing into which the measuring unit is inserted, and Fig. 2 is a sectional view taken along line 2-2 in Fig. 1. 10...outer housing, 12...closing ring, 16...inlet Opening, 18...Exit opening, 42
... Seat, 44 ... Measurement unit, 46 ... Impeller housing, 48 ... Impeller, 50 ...
Adapter ring, 56... Counter sheet, 62
... Sleeve part (apron), 82 ... Counter sheet.

Claims (1)

[Claims] 1. An impeller housing that houses an impeller;
a recording mechanism disposed on the impeller housing and driven by said impeller via a magnetic coupling, the outer housing of the flow meter having a first portion defining an inflow opening 20 and an outflow opening 22; A second portion 12, 14 is removable for insertion of the unit into an outer housing, the outer housing having an inlet chamber 28 communicating an interior space thereof with the inlet opening 20 and an outlet chamber communicating with the outlet opening 22. A measuring unit of a flow meter having at least an internal partition wall 26 separating a chamber 30, comprising an adapter ring into which the impeller housing is inserted for attachment to an outer housing of the fluid flow meter; 26 has an opening 24 that forms a first seat for the adapter ring 50, and the adapter ring 50 has a cylindrical shape and has a second seat, which is a seat opposite to the first seat, on the outside thereof. A third seat is formed inside the seat, and the third seat is a seat opposite to a fourth seat formed on the impeller housing, and the adapter ring is attached to a peripheral wall of the impeller housing. an enclosing apron portion radially spaced from the peripheral wall portion, and the peripheral wall portion has circumferentially juxtaposed inlet openings 68, the inlet openings 68 of the impeller housing 46 being the only portion of the peripheral wall 66; A measuring unit for a flowmeter, characterized in that the apron portion 62 of the adapter ring 50 extends in the axial direction to at least a region of the peripheral wall 66 of the impeller housing 46. 2. The invention according to claim 1, wherein the impeller housing 46 includes a plurality of outlet openings 70 axially spaced from an inlet opening 68 thereof, and the adapter ring 50 has a cylindrical portion 64, and the adapter ring 50 has a cylindrical portion 64. A measuring unit characterized in that the section 64 surrounds the outlet opening 70 at a radial distance from the opening 7 and cooperates with the external part of the measuring unit to form an outflow gap.