Utility meter assembly and remote module and mounting apparatus and assembly

• US 5,519,387 A
• Filed: 04/14/1994
• Issued: 05/21/1996
• Est. Priority Date: 04/14/1994
• Status: Expired due to Term

• Current Assignee: Motorola Solutions, Inc.
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Besier, Emil, Corsatea, Liviu, Wrzesinski, Stanley
• Primary Examiner(s): Swarthout, Brent A.
• Assistant Examiner(s): MANNAVA, ASHOK K
• Application Number:
  US08/227,418
• Time in Patent Office: 768 Days
• Field of Search: 343/702, 343/701, 343/703, 343/708, 361/659, 340/870.02, 340/870.03, 340/870.07, 340/870.11, 324/142, 324/110, 324/113
• US Class Current: 340/870.02
• CPC Class Codes: G01R 11/04 Housings; Supporting racks; Arrangements of terminals
• CPC Class Codes: G01R 22/00 Arrangements for measuring time integral of electric power or current, e.g. electricity meters

Abstract

Utility meter assembly (10) includes a utility meter (11) having an external housing (12) adjacent to which is mounted a remote meter reading module housing (25) that preferably is mounted to a pair of upstanding cylindrical posts (15 and 16) that rise from the utility meter housing (12). Preferably, flexible pins (32), which preferably are part of the module housing (25), bias the module housing (25), and a ground plane plate (26) within the module housing, towards a conductive surface (14) of the utility meter housing (12). The ground plane plate (26) coupled to the meter housing (12) and to the conductive surface (14) takes advantage of the meter as an extended ground plane or a counterpoise and thus increases the radiation efficiency of the antenna. This configuration permits the use of a shorter antenna (23) for power efficient transmission of meter data. Also, the configuration of the module housing (25) provides an improved snap on assembly for mounting a module housing ( 25) to a pair of posts (15,16).

Claims

1. Utility meter assembly comprising:

at least one utility meter having measuring apparatus for measuring use of a utility, said measuring apparatus positioned within an external housing having at least one conductive metal surface; and

a remote meter reading module positioned outside of and mounted adjacent to said utility meter external housing and electrically connected to said measuring apparatus, said remote meter reading module having a transmitter and an antenna for wireless transmission of meter data developed in accordance with data provided by said measuring apparatus,

wherein one end of said antenna is electrically connected to a conductive ground plane plate within said remote meter reading module, said conductive ground plane plate forming one plate of a capacitor with said conductive metal surface of said utility meter external housing forming another plate of said capacitor, said capacitor plates being spaced apart and capacitively coupling said antenna to said meter housing and thereby substantially altering the effective electrical length of said antenna, and improving the radiation power efficiency by using the meter housing as a ground extension.

2. Utility meter assembly according to claim 1 wherein said remote meter reading module has a housing with foot projections thereof in contact with said utility meter external housing, said foot projections determining the spacing between said capacitor plates by determining the spacing between said conductive metal surface of said utility meter external housing and said conductive ground plane plate of said remote meter reading module.

3. Utility meter assembly according to claim 2 wherein said remote meter reading module housing includes bias means for biasing said foot projections into contact with said utility meter external housing.

4. Utility meter assembly according to claim 3 wherein said remote meter reading module housing is primarily molded plastic.

5. Utility meter assembly according to claim 3 wherein said bias means comprises flexible portions of said remote meter reading module housing which cooperate with rigid projections extending from said utility meter external housing to bias said foot against said utility meter external housing.

6. Utility meter assembly according to claim 5 wherein said remote meter reading module housing is primarily molded plastic and said bias means comprises flexible plastic pin projections formed integral with said remote meter reading module housing.

7. Utility meter assembly according to claim 6 wherein said rigid projections comprise a pair of upstanding cylindrical posts extending from a main body of said utility meter external housing, each of said cylindrical posts having integral annular shoulders at a spacing above said utility meter external housing main body, said annular shoulders being in contact with said plastic pins to form said bias means.

8. Utility meter assembly according to claim 7 wherein said remote meter reading module housing has first and second portions which, together with said cylindrical posts, provide a snap on assembly for mounting said module housing to said cylindrical posts.

9. Utility meter assembly according to claim 8 wherein said first and second portions of said remote meter reading module housing each have partial arcuate portions in contact with said cylindrical posts and wherein said remote meter reading module housing includes a flexible retaining arm extending therefrom and having a free end in contact with one of said cylindrical posts.

10. Utility meter assembly according to claim 9 wherein said cylindrical posts are spaced apart by a predetermined dimension with said arcuate portions of said remote meter reading module housing positioned between said cylindrical posts, said arcuate portions being positioned between said annular shoulders on said cylindrical posts and said main body of said utility meter external housing.

11. Remote module usable for attachment to a utility meter comprising:

a remote meter reading module to be positioned outside of and mounted adjacent to a utility meter external housing and electrically connected to said utility meter, said remote meter reading module having a transmitter and an antenna for wireless transmission of meter data developed in accordance with data to be received by said module from said utility meter,

wherein one end of said antenna is electrically connected to a conductive ground plane plate within said remote meter reading module, said conductive ground plane plate forming one plate of a capacitor for capacitively coupling to the meter housing and thereby substantially altering the effective electrical length of said antenna.

12. Remote module according to claim 11 wherein said remote meter reading module has a housing with foot projections thereof to be positioned in contact with said utility meter.

13. Remote module according to claim 12 wherein said remote meter reading module housing includes bias means for biasing said foot projections into contact with said utility meter, and wherein said remote meter reading module housing is primarily molded plastic and said bias means comprises flexible plastic pin projections formed integral with said remote meter reading module housing.

14. Remote module according to claim 13 wherein first and second peripheral portions of said remote meter reading module housing each have partial arcuate portions and wherein said remote meter reading module housing includes a flexible retaining arm extending therefrom and having a free end.

15. Remote module according to claim 14 wherein each of said arcuate portions of said remote meter reading housing form a portion of a circular path centered about an axis normal to said ground plane plate with said axes being spaced apart at a predetermined dimension and positioned such that said axes are spaced away from said remote meter reading housing, and wherein said free end of said flexible arm extension is generally positioned, in its normal position, along the circular path formed about one of said axis with said actuate portion defining a portion of that circular path.

16. Remote module mounting apparatus usable for attachment of a module to a utility meter, comprising:

a module housing, with a main housing body having electronics therein, for mounting to two meter posts,

said module housing having a first peripheral portion thereof having a partial arcuate shape and a second peripheral portion having a partial arcuate shape, said module housing also having a flexible arm extension with a free end of said flexible arm extension adjacent said second arcuate portion, said free arm normally spaced away from said main housing body but deflectable toward said main housing body.

17. Remote module mounting apparatus according to claim 16 wherein said main housing body comprises mainly molded plastic and wherein said arcuate portions and said flexible arm extension are molded plastic.

18. Remote module mounting apparatus according to claim 17 wherein said main housing body includes at least one flexible pin adjacent and extending from each of said arcuate portions.

19. Remote module mounting apparatus according to claim 18 wherein each of said arcuate portions generally form a portion of a circular path centered about an axis with said axes being spaced apart at a predetermined dimension and are positioned such that said axes are spaced away from said module housing, and wherein said free end of said flexible arm extension is generally positioned, in its normal position, along the circular path formed about one of said axis with said arcuate portion defining a portion of that circular path.

20. Remote module mounting assembly comprising:

a module housing with a main housing body having electronics therein;

two upstanding posts to which said main housing body is to be attached, wherein said posts each have a cylindrical axis and wherein the cylindrical axes are spaced apart by a predetermined dimension and are positioned such that said axes are spaced away from said module housing;

the main housing body having a first peripheral portion thereof having a partial arcuate shape and a second peripheral portion having a partial arcuate shape, said main housing body also having a flexible arm extension with a free end of said arm positioned adjacent said second arctuate portion, said free arm normally spaced away from said main housing body but deflectable toward said main housing body;

each of said arctuate portions in contact with an associated one of said posts with said free end of said flexible arm extension also in contact with one of said posts.

21. Remote module mounting assembly according to claim 20 wherein flexible pins are positioned on said main housing body adjacent each of said arcuate portions.

22. Remote module mounting assembly according to claim 21 wherein each of said posts has an annular shoulder formed thereabout with said flexible pins contacting said annular shoulders.

23. Remote module mounting assembly according to claim 22 wherein said main housing body comprises mainly molded plastic material and wherein said flexible arm extension and said flexible pins comprise said molded plastic material and are integral with said main housing body.