Molded flow restrictor

• US 8,756,990 B2
• Filed: 03/29/2011
• Issued: 06/24/2014
• Est. Priority Date: 04/09/2010
• Status: Active Grant

• Current Assignee: Honeywell International Inc.
• Original Assignee: Honeywell International Inc.
• Inventors: Speldrich, Jamie
• Primary Examiner(s): Caputo, Lisa
• Assistant Examiner(s): Hernandez-Prewit, Roger
• Application Number:
  US13/074,932
• Publication Number:
  US 20110247411A1
• Time in Patent Office: 1,183 Days
• Field of Search: 732/73, 732/042.1, 738/625.82, 264/276
• US Class Current: 73/273
• CPC Class Codes: B29C 45/0025 Preventing defects on the moulded article, e.g. weld lines, shrinkage marks preventing defects on the preformed parts or layers B29C45/14836
• CPC Class Codes: B29C 45/2628 with mould parts forming holes in or through the moulded article, e.g. for bearing cages
• CPC Class Codes: G01F 1/6842 with means for influencing the fluid flow
• CPC Class Codes: G01F 5/00 Measuring a proportion of the volume flow
• CPC Class Codes: G01F 5/005 by measuring pressure or differential pressure, created by the use of flow constriction
• CPC Class Codes: Y10T 29/4998 Combined manufacture including applying or shaping of fluent material

Abstract

The present disclosure relates generally to flow sensors, and more particularly, to devices and methods for providing a pressure drop through a flow sensor at a given flow rate. In one illustrative embodiment, a sensor assembly includes a housing with a first flow port and a second flow port. The housing may define a fluid channel extending between the first flow port and the second flow port, with a sensor positioned in the housing and exposed to the fluid channel. The illustrative sensor may be configured to sense a measure related to the flow rate of a fluid flowing through the fluid channel. A flow restrictor may be situated in and integrally molded with at least one of the first flow port and the second flow port. The flow restrictor may be configured to accurately provide a pressure drop through the flow sensor at a given flow rate.

Claims

1. A flow sensor housing, comprising:

a housing body including an inlet flow port and an outlet flow port, the housing body defining a fluid channel extending between the inlet flow port and the outlet flow port;

a first region of the fluid channel defined by side walls, the first region positioned in and integrally molded with the housing body, wherein the side walls of the first region define a first cross-sectional area;

a second region of the fluid channel defined by side walls, the second region positioned in and integrally molded with the housing body, the second region disposed immediately upstream or downstream of the first region, wherein the side walls of the second region are laterally spaced outward from the side walls of the first region and define a second cross-sectional area that is greater than the first cross-sectional area, and wherein an interconnecting surface extends between the side walls of the first region and the side walls of the second region; and

flash integrally molded with the housing body and extending the side walls of the first region into the second region, wherein the flash, the interconnecting surface and the side walls of the second region collectively define a volume that is open to and with a space between the flash and the side walls of the second region, the space being in fluid communication with the fluid channel.

2. The flow sensor assembly of claim 1, further comprising:

a flow sensor exposed to the fluid channel, the flow sensor configured to sense a measure related to a flow rate of a fluid flowing through the fluid channel.

3. The flow sensor assembly of claim 2, wherein the second region is disposed immediately upstream of the first region and the first region is positioned downstream of the flow sensor.

4. The flow sensor assembly of claim 2, wherein the second region is disposed immediately downstream of the first region and the first region is positioned upstream of the flow sensor.

5. The flow sensor assembly of claim 2, wherein the first region is positioned downstream of the flow sensor and, wherein during operation of the flow sensor assembly, a fluid passes through the inlet flow port, across the flow sensor, through the first region, past the flash and into the second region, and through the outlet flow port.

6. The flow sensor assembly of claim 2, wherein the first region is positioned upstream of the flow sensor and, wherein during operation of the flow sensor assembly, a fluid passes through the inlet flow port, through the first region, past the flash and into the second region, across the flow sensor, and through the outlet flow port.

7. The flow sensor assembly of claim 2, wherein the fluid channel includes two or more bends of about 90 degrees, wherein a first bend is between the inlet flow port and the flow sensor and a second bend is between the flow sensor and the outlet flow port.

8. The flow sensor assembly of claim 1, wherein the flash has a generally annular shape and extends in an upstream direction or a downstream direction from the first region.

9. A flow sensor assembly, comprising:

a housing body including an inlet flow port and an outlet flow port, the housing body defining a fluid channel extending between the inlet flow port and the outlet flow port;

a flow sensor exposed to the fluid channel, the flow sensor configured to sense a measure related to a flow rate of a fluid flowing through the fluid channel; and

a flow restrictor positioned in the fluid channel and monolithically formed with the housing body, the flow restrictor configured to provide a predetermined pressure drop through the flow channel at a given flow rate, wherein the flow restrictor includes a restricted cross-section portion immediately adjacent a less-restricted cross-section portion, wherein cross-sections of the restricted cross-section portion and the less-restricted cross-section portion are generally concentric, and wherein traversing between the restricted cross-section portion and the less-restricted cross-section portion entails an abrupt change in fluid channel cross-sectional area; and

flash monolithically formed with the flow restrictor in the fluid channel, wherein the flash is positioned in the fluid channel such that the flash does not reduce the cross-sectional area of the restricted cross-section portion of the flow restrictor and is positioned on an upstream side of the flow restrictor.

10. The flow sensor assembly of claim 9, wherein the flow restrictor is positioned downstream of the flow sensor in the fluid channel and, when during operation of the flow sensor assembly, a fluid passes through the inlet flow port, across the flow sensor, through the flow restrictor, and through the outlet flow port.

11. The flow sensor assembly of claim 9, wherein the flow restrictor is positioned upstream of the flow sensor in the fluid channel and, when during operation of the flow sensor assembly, a fluid passes through the inlet flow port, through the flow restrictor, across the flow sensor, and through the outlet flow port.

12. The flow sensor assembly of claim 9, wherein the fluid channel includes two or more bends of about 90 degrees, wherein a first bend is between the inlet flow port and the flow sensor and a second bend is between the flow sensor and the outlet flow port.

13. A flow sensor assembly, comprising:

a first housing member;

a second housing member, the second housing member including a first flow port and a second flow port, wherein the first housing member and the second housing member define a fluid channel extending between the first flow port and the second flow port;

a flow sensor positioned between the first housing member and the second housing member adjacent to the fluid channel, the flow sensor configured to sense a measure related to a flow rate of a fluid flowing through the fluid channel;

a flow restrictor integrally molded with the first flow port and configured to provide a predetermined pressure drop through the fluid channel at a given flow rate, wherein the flow restrictor is completely defined by the second housing member to include an opening having a diameter, wherein the flow restrictor includes a length and has a length to diameter ratio of about 4.0 or smaller; and

wherein the fluid channel includes two or more bends of about 90 degrees, wherein a first bend is between the first flow port and the flow sensor and a second bend is between the flow sensor and the second flow port.

14. The flow sensor assembly of claim 13, wherein the first flow port is an inlet flow port and, wherein during operation of the flow sensor assembly, a fluid passes through the first flow port, through the flow restrictor, across the flow sensor, and through the second flow port.

15. The flow sensor assembly of claim 13, wherein the first flow port is an outlet flow port and, wherein during operation of the flow sensor assembly, a fluid passes through the second flow port, across the flow sensor, through the flow restrictor, and through the first flow port.

16. The flow sensor assembly of claim 13, wherein the ratio of the length to diameter of the flow restrictor is about 2.0 or smaller.

17. The flow sensor assembly of claim 13, further comprising flash monolithically formed with the flow restrictor in the fluid channel, wherein the flash is oriented to define a cross-sectional area of the fluid channel equal to or greater than a cross-sectional area of the fluid channel defined by the opening of the flow restrictor.

18. The flow sensor assembly of claim 14, wherein the flash is configured to extend from the flow restrictor in a direction parallel with fluid flow in the fluid channel at the flow restrictor.