Flowmeter

• US 4,733,570 A
• Filed: 12/04/1986
• Issued: 03/29/1988
• Est. Priority Date: 12/12/1985
• Status: Expired due to Term

• Current Assignee: BIEO AG
• Original Assignee: BIEO AG
• Inventors: Peters, Paulus J.
• Primary Examiner(s): Goldstein, Herbert
• Application Number:
  US06/941,800
• Time in Patent Office: 481 Days
• Field of Search: 73/861.33, 73/861.35, 73/861.77, 73/861.83, 73/861.89, 73/861.92
• US Class Current: 73/861.33
• CPC Class Codes: G01F 1/103 with radiation as transfer means to the indicating device, e.g. light transmission

Abstract

A flowmeter with a rotor (21) is provided with blades (22) which are rotatably and coaxially supported in an essentially cylindrical bore (15). The rotor (21) is preceded by a screw-shaped and coaxial distributor (16) imparting a spin to the incident medium before this medium loads the blades (22). The rotation of the rotor (21) is detected in a contactless manner by a light barrier (29, 30, 31). In order to linearize as much as possible the flowmeter characteristics also in the case of impulsive flow, the rotor (21) is provided with blades of which the surfaces (22'"'"') loaded with the spinning flow are concave and are curved solely about axes of curvature which are parallel to the rotor axis (15'"'"'). Each blade (22) is provided with a slot (28) starting at one end of its side edges. The light beam (29) of the light barrier (29, 30, 31) orthogonally crosses the rotor axis (15'"'"') at a distance whereby one count signal is generated for each blade.

Claims

1. A flowmeter for measuring flowing media comprising:

a rotor having blades and an axis of rotation;

means for rotatably and coaxially mounting said rotor within a substantially cylindrical bore;

a screw shaped stream distributor coaxially and stationarily mounted within said bore upstream of said rotor;

said blades having concave loaded surfaces;

said stream distributor dividing the incident medium into partial flows and imparting to the partial flows a spin;

said partial flows having a spin impinging on said concave loaded surfaces of said blades;

a light source for transmitting a light beam to a light receiver;

said light beam being repeatedly momentarily interrupted by the rotating rotor;

said light beam crossing said axis of rotation substantially orthogonally;

each of said concave loaded surfaced being curved exclusively about axes of curvature parallel to said axis of rotation;

each of said blades having side edges and comprising a slot extending parallel to said axis of rotation and beginning at one of said side edges;

and said slot forming a passage for briefly transmitting said light beam from said light source to said light receiver when said rotor is rotating.

2. The flowmeter of claim 1 wherein the slot begins at the leading edge of each blade.

3. The flowmeter of claim 1 wherein the rotor has three blades and is intragally made of plastic.