FR2851809A1 - Gear support for fluid flow counter includes support bearing projecting into recess within wheel to provide axial and radial guidance - Google Patents

Abstract

The mechanism includes a gear wheel (6) held between two supports (7,8). The second of these supports includes a shaft (8A) centred on the axis of rotation which provides both axial and radial guidance for the support of the gear wheel. The gear wheel has recess in its centre receiving the shaft of the bearing support. The mechanism provides a total counter in measuring fluid flow. This includes a gear wheel (6) which is mounted to rotate about an axis (A), held between two supports (7,8). The second of these supports includes a shaft (8A) centred on the axis of rotation. The projecting end of the shaft engages a corresponding seating in the gear wheel and forms a bearing. This provides both axial and radial guidance for the support of the gear wheel. The gear wheel has recess in its centre, and projection on the opposite side, such that the shaft of the bearing support passes into the wheel by a distance greater than the thickness of the wheel. The upper support (7) has a surface (7A) which engages the upper surface of the disc.

Description

i

  The present invention relates to a gear arrangement for a fluid meter totalizer.

  An example of a water meter is shown in Figure 1.

  This counter 1 comprises a cover 2 provided with an inlet pipe and an outlet pipe. In this tank 2 is arranged a measurement chamber which can be for example of the volumetric type with oscillating piston or of the turbine type. This measurement chamber comprises a rotary output shaft, the rotation of which is transmitted by means of gears contained in a totalizer 3 to consumption recording devices which can be, for example, an encrypted drum or a rotating index 4. The counter 1 can also include a module 5 for remote reading of this consumption.

  For certain applications, it is necessary to minimize the height of the meter 1. This is essentially the case during specific installations of the meter on pipes leaving only a reduced space available for the meter.

  This problem is amplified with the use of remote reading modules 5 installed on the meter and increasing the total overall height of the latter.

  A known solution for this is to design a cavity in the totalizer 3 which receives the remote reading module 5. However, this solution requires a complex rearrangement of the totalizer and the parts 25 it contains and is limited by the height of the gears.

  Furthermore, the gears contained in this totalizer 3 are generally drive disks as shown in FIG. 2.

  The disc 6 is substantially horizontal, rotatable about a substantially vertical axis A and supported by an upper support part 7 and 30 a lower support part 8. The lower and upper supports are generally symmetrical and include a substantially vertical rod F: \ Salle \ FP000540 \ PREMDEP'ADMIN \ Text deposited.doc 6 ', 6 "carried by the gear disc, centered on the axis of rotation A and pivoting respectively on the bottom of a hollow bearing 7', 8 'having axis of symmetry the axis of rotation and carried by the upper part 7 or lower 8.

  In the case of a reduction in transmission ratio, the disc 6 5 comprises a sub-disc 6 "'bearing a toothing. Such gear arrangements are relatively bulky in height.

  The invention proposes to solve the problem of optimizing the overall dimensions at the height of the counter by means of a gear arrangement of minimized height while ensuring correct maintenance and guidance of these toothed wheels. To do this, the invention provides a gear arrangement for a totalizer of a fluid meter, comprising a gear disc rotating around an axis of rotation and supported by supports on a first support part and a second support part ensuring its axial and radial guide, characterized in that it comprises a single radial guide arrangement.

  In addition to minimizing the height of the counter, the invention also has the significant advantage of requiring no specific guide arrangement on one of the support parts, in addition to axial retention. Thus, the mounting of the gear disc is dependent on the correct positioning perpendicular to the axis of rotation of only one of the support parts, the part carrying the radial guide arrangement. This is particularly advantageous in the case of a totalizer variant with a new cyclic volume requiring a modification of the gear train.

  According to a preferred embodiment of the invention, said radial guide arrangement 25 consists of a first support comprising a rod centered on said axis of rotation, pivoting on the bottom of a hollow bearing having said axis of symmetry said axis of rotation and carried by the corresponding support part, said hollow bearing being shaped in the gear disc.

  This embodiment also has the advantage of reducing the mass and inertia of the gear disc. This is an important advantage F: \ Salle \ FP000540 \ PREMDEP \ ADMIN \ Text deposited.doc since mass and inertia are key factors to obtain good metrological properties.

  Another advantage of this embodiment lies in the fact that only a hollow bearing is used. This limits the retention of particles or debris in this type of bearing.

  Another advantage compared to the prior art is a saving of material and cost taking into account the simplicity of the parts of the arrangement.

  According to a preferred embodiment of the invention, said hollow bearing is of depth greater than the thickness of the gear disc.

  In this case, preferably, said bottom of the hollow bearing is formed by a wall protruding on one face of the gear disc.

  Advantageously, said wall carries a gear toothing.

  According to an alternative embodiment, said rod consists of two sections of cylinder of different diameter and said bearing comprises a shoulder connecting two cylindrical cavities of corresponding diameter.

  Advantageously, the other of said supports said second support comprises a wall of the corresponding support piece substantially parallel to the disc and on which the gear disc is in rotary contact around said axis of rotation.

  According to a particular embodiment, said gear disc is horizontal and said axis of rotation vertical.

  In this case, preferably, the first support is the lower support and the second support is the upper support.

  In addition, according to this particular embodiment, the hollow bearing 25 used is directed downwards. This removes any retention of particles or debris by gravity.

  Figure 1 already considered is therefore a schematic view of a fluid meter and more specifically water.

  Figure 2 already considered is a vertical sectional view of a gear arrangement according to the prior art.

  Figure 3 is a vertical sectional view of a gear arrangement, in accordance with a first embodiment of the invention.

  F: \ Salle \ FP000540 \ PREMDEP'ADMIN \ Text deposited.doc Figure 4 is a vertical sectional view of a gear arrangement, in accordance with a second embodiment of the invention.

  Figure 5 is a vertical sectional view of a gear arrangement, according to an alternative embodiment of the invention.

  Commonly to the two FIGS. 3 and 4, a gear arrangement for a totalizer for a fluid meter, comprises a gear disc 6 which is substantially horizontal, rotatable about a substantially vertical axis A and supported by an upper support part 7 and a lower support part 8.

  The lower support comprises a substantially vertical rod 8A centered on the axis of rotation A and carried by the lower support part 8.

  This rod 8A is rotatable on the bottom 6A of a hollow bearing 6B having for axis of symmetry the axis of rotation A and shaped in the gear disc 6.

  This hollow rod / bearing arrangement constitutes an axial and radial guide arrangement.

  This hollow bearing 6B is of depth greater than the thickness of the gear disc and its bottom is formed by a wall 6C protruding on the upper face of the gear disc 6.

  This protuberance advantageously carries a gear teeth 20, in the case of a reduction in transmission ratio.

  The upper support part 7 has for its part a substantially horizontal wall 7A on which the wall 6C of the gear disc 6 is in rotary contact about the axis of rotation A. It constitutes a guide arrangement that is only axial.

  According to the first variant shown in Figure 1, the rotation of the disc 6 relative to the upper support part 7 is achieved by means of a rotation surface, preferably a pivot point, or more complexly of the type ball or anti-friction coating, carried by the disc 6. According to the second variant shown in FIG. 2, the rotation of the disc 6 relative to the upper support part 7 is carried out by means of a rotation surface carried by the upper part 7.

  F: \ Salle \ FP000540 \ PREMDEP \ ADMIN \ Text deposited.doc More generally, within the framework of the invention, these rotation surfaces, preferably pivot points, can be provided either on the disc 6, or on the corresponding lower or upper support part 7, 8.

  According to the variant shown in Figure 5, the lower support comprises a rod 8'A substantially vertical centered on the axis of rotation A and carried by the lower support part 8. This rod 8'A is rotatable on the bottom 6'A a hollow bearing 6'B having the axis of symmetry the axis of rotation A and shaped in the gear disc 6. This hollow rod / bearing arrangement 10 constitutes an axial and radial guide arrangement.

  Here the rod 8'A consists of two sections of cylinder of different diameter, the end diameter being smaller. The bearing 6'B has a shoulder connecting two cylindrical cavities of corresponding diameter. Thus, the radial guidance is improved by means of two guide and support surfaces.

  In the embodiment described above, the rod is carried by the lower support part and the upper support part does not have any specific arrangement. The reverse arrangement, rod carried by the upper support part and lower support part not comprising any specific arrangement, also comes within the scope of the invention.

  Furthermore, the example described relates to a horizontal gear disc and a vertical axis of rotation. It is within the reach of those skilled in the art to adapt this example to a disc oriented differently, in particular vertical with horizontal axis of rotation.

  F: \ Salle \ FP000540 \ PREMDEP'ADMIN \ Text deposited.doc

Claims (9)

  1. Gear arrangement for totalizer (3) of fluid meter, comprising a gear disc (6) rotatable about a rotation axis (A) and supported by supports on a first part 5 support (7) and a second support part (8) ensuring its axial and radial guiding, characterized in that it comprises a single radial guiding arrangement.   2. Arrangement according to claim 1, characterized in that said radial guide arrangement consists of a first support 10 comprising a rod (8A) centered on said axis of rotation (A), pivoting on the bottom of a hollow bearing having as axis of symmetry said axis of rotation and carried by the corresponding support part (8), said hollow bearing (6B) being shaped in the gear disc (6).   3. Arrangement according to claim 2, characterized in that said hollow bearing (6B) is deeper than the thickness of the gear disc (6).   4. Arrangement according to claim 3, characterized in that said bottom (6A) of the hollow bearing (6B) is formed by a wall (6C) protruding on one face of the gear disc (6).   5. Arrangement according to claim 4, characterized in that said wall (6C) carries a gear toothing.   6. Arrangement according to one of claims 2 to 5, characterized in that said rod (8'A) consists of two sections of cylinder of different diameter and said bearing (6'B) has a shoulder connecting two cylindrical cavities of corresponding diameter.   7. Arrangement according to one of the preceding claims, characterized in that the other of said supports said second support comprises a wall (7A) of the corresponding part (7) substantially parallel to the disc (6) and on which is in rotary contact the gear disc (6) 30 around said axis of rotation (A).   F: \ Salle \ FP000540 \ PREMDEP'ADMIN \ Text deposited.doc 8. Arrangement according to one of the preceding claims, characterized in that said gear disc (6) is horizontal and said axis of rotation (A) vertical.   9. Arrangement according to claim 7, characterized in that the first support is the lower support (8) and the second support is the upper support (7).   F: \ Salle \ FP000540 \ PREMDEP \ 4DMIN \ Text deposited.doc