Water meter with an anti-reverse-rotation device

• US 4,489,600 A
• Filed: 03/03/1983
• Issued: 12/25/1984
• Est. Priority Date: 09/03/1982
• Status: Expired due to Fees

• Current Assignee: Shinhan Kongki Company Limited
• Original Assignee: Shinhan Kongki Company Limited
• Inventors: Han, Eui M.
• Primary Examiner(s): Ruehl, Charles A.
• Application Number:
  US06/471,851
• Time in Patent Office: 663 Days
• Field of Search: 73/275, 73/861.79, 73/861.87, 73/861.88, 73/861.94, 235/94 R
• US Class Current: 73/275
• CPC Class Codes: G01F 1/075 with magnetic or electromagnetic coupling to the indicating device
• CPC Class Codes: G01F 15/06 Indicating or recording devices

Abstract

An improved magnetic rotor type water meter having an anti-reverse-rotation device for preventing the reverse rotation of the pointer driving gear of the water meter, although the rotor or impeller of the water meter is rotated in the reverse direction by a counterflow from the outlet or by any type of fluid pressures applied to the outlet.

Claims

1. A magnet-rotor type water meter with an anti-reverse-rotation device comprising:

a rotor chamber accommodating a rotor with rotor shaft wherein said rotor shaft is provided with a ferrite magnet securely inlaid onto the upper end thereof,

a hermetically enclosed inner casing located above said rotor chamber,

a scale plate mounted on the upper end of said inner casing,

an instrument gear assembly housed in said inner casing wherein said instrument gear assembly includes a central main shaft and a pointer driving gear, said central main shaft being provided with a ferrite magnet securely inlaid onto the lower end thereof and said pointer driving gear being provided with an instrument pointer securely mounted on the upper end of the gear shaft of said pointer driving gear,

whereby said ferrite magnet magnetically cooperates with said ferrite magnet as said rotor shaft is rotated and thereby said central main shaft is rotated to drive said instrument gear assembly and thus to rotate said instrument pointer, and

characterized in that one or more stepped back stops are formed on the annular upper side of said pointer driving gear, and each of said stepped back stops is gradually sloped down in the normal rotational direction R₁ to form an inclined plane, and one or more stop pin cylinders are provided on the underside of said scale plate in the vicinity of the upper gear shaft, and one or more stop pins are slidably inserted each into said stop pin cylinders, whereby the lower ends of said stop pins smoothly slide on said inclined planes while moving up- and downward within said stop-pin cylinders due to the cam action of said inclined planes without preventing the rotation of said pointer driving gear in the normal direction R₁, whereas said stepped back stops are caught by said stop pins, thereby preventing the reverse rotation of said pointer driving gear when rotating in the reverse direction R₂.

2. A magnet rotor type water meter with an anti-reverse-rotation device according to claim 1 characterized in that said device comprises more than two stepped back stops, stop pins and stop pin cylinders respectively.

3. A magnet rotor type water meter with an anti-reverse-rotation device according to claim 2 characterized in that said stop pin cylinders are formed on the underside of said scale plate.

4. A magnet rotor type water meter with an anti-reverse-rotation device according to claim 2 characterized in that said stepped back stops are formed along the radius line drawn through the center of said pointer driving gear on the upper side thereof, and said back stops are gradually sloped down in the normal rotational direction R₁ to form said inclined planes.