Wet-tap sensor assembly and related method

• US 6,640,658 B1
• Filed: 06/11/2002
• Issued: 11/04/2003
• Est. Priority Date: 06/11/2002
• Status: Expired due to Fees

• Current Assignee: Georg Fischer Signet, LLC (Georg Fischer AG)
• Original Assignee: Signet Scientific Company
• Inventors: Burkhardt, Gert, Guerrero, Sergio
• Primary Examiner(s): Williams, Hezron
• Assistant Examiner(s): GARBER, CHARLES D
• Application Number:
  US10/170,243
• Time in Patent Office: 511 Days
• Field of Search: 738/665, 738/638.5, 204/401, 204/416, 204/421, 204/422, 204/433
• US Class Current: 73/866.5
• CPC Class Codes: G01D 11/30 Supports specially adapted for an instrument; Supports specially adapted for a set of instruments

Abstract

This invention resides in a wet-tap sensor assembly and related method for use with containers, such as, pressurized pipes of flowing liquids to measure the contents therein. In use, the housing is securely attached to over a hole in an external wall of the container, and a sensor cartridge of the assembly movably inserts and retracts a sensor probe relative to the contents. With the sensor probe in place, whether inserted or retracted, the assembly has means to prevent the contents from escaping. The sensor assembly includes a locking mechanism that locks the sensor cartridge in the retracted position allowing for removal of the sensor probe while preventing against inadvertent displacement of the sensor cartridge, and preferably includes a cap positioned over the sensor cartridge that prohibited removal of the sensor probe without first retracting the sensor cartridge and that disengages the locking mechanism.

Claims

1. A sensor assembly, configured to be mounted to an external wall of a container for supporting a sensor to measure a predetermined parameter of a fluid located therein, the sensor assembly comprising:

a housing configured to be securely positioned relative to the external wall of the container, the housing having a lower portion and an upper portion, and the housing defining a cavity with a first opening at the lower portion and a second opening at the upper portion;

a sensor cartridge mounted for movement in the cavity, between an inserted position and a retracted position, the cartridge defining an elongated opening with an upper end for receiving the sensor probe and a lower end for exposing a sensing end of a sensor probe when in the inserted position;

a gasket configured to contact both the lower portion of the sensor cartridge below the lower end of the elongated opening and a surface of the housing defining the cavity when the cartridge is in the retracted position, thereby providing a liquid-proof, pressure-resistant seal between the sensor cartridge and the housing at their respective lower portions; and

a locking mechanism configured to secure the sensor cartridge in the retracted position, the locking mechanism including

a locking pin mounted for movement in a recess of the housing adjacent to the sensor cartridge and configured to interface with the sensor cartridge to secure the sensor cartridge when in the retracted position, and

a resilient member attached to the locking pin configured to urge the locking pin to engage the sensor cartridge.

2. A sensor assembly as defined in claim 1, wherein the sensor assembly further includes a guide rod attached at a first end to the upper portion of the sensor assembly and projected downward therefrom, the guide rod defines a notch configured to overlie the locking pin when the sensor cartridge is in the retracted position, allowing the locking pin to project forward, securing the sensor cartridge in the retracted position.

3. A sensor assembly as defined in claim 2, further comprising a cap configured to be placed over the upper portion of the sensor cartridge and to engage and disengage the locking mechanism.

4. A sensor assembly configured to be mounted to an external wall of a container for supporting a sensor to measure a predetermined parameter of a fluid located therein, the sensor assembly comprising:

a housing configured to be securely positioned relative to the external wall of the container, the housing having a lower portion and an upper portion, and the housing defining a cavity with a first opening at the lower portion and a second opening at the upper portion;

a sensor cartridge mounted for movement in the cavity, between an inserted position and a retracted position, the cartridge defining an elongated opening with an upper end for receiving the sensor probe and a lower end for exposing a sensing end of a sensor probe when in the inserted position;

a gasket configured to contact both the lower portion of the sensor cartridge below the lower end of the elongated opening and a surface of the housing defining the cavity when the cartridge is in the retracted position, thereby providing a liquid-proof, pressure-resistant seat between the sensor cartridge and the housing at their respective lower portions;

a locking mechanism configured to secure the sensor cartridge in the retracted position and having an a locking pin mounted to the housing; and

a cap, having a longitudinal axis, configured to be placed over the upper portion of the sensor cartridge and to engage and disengage the locking mechanism.

5. A sensor assembly as defined in claim 4, wherein the cap has a first radial orientation and a second radial orientation about its longitudinal axis when positioned on the sensor cartridge in the retracted position, the first orientation allowing the locking mechanism to engage and the second orientation disengaging locking mechanism.

6. A sensor assembly as defined in claim 5, wherein:

the cap defines an inner cavity configured to limit placement of the cap upon the sensor cartridge to selected orientations about its longitudinal axis; and

the upper portion of the sensor cartridge is configured to receive the cap in only the selected orientations.

7. A sensor assembly as defined in claim 6, wherein:

the cap has an alignment bar positioned in the inner cavity, and

the upper portion of the sensor cartridge has a planar surface on a longitudinal side thereof configured to allow placement of the cap upon the sensor cartridge.

8. A method of operating a sensor assembly comprising:

inserting a sensor probe having a sensing end into a sensor assemble mounted to an external wall of a container or pipe, the sensor assembly including

a housing configured to be securely positioned relative to the external wall of the container, the housing having lower portion and an upper portion, and the housing defining a cavity with a first opening at the lower portion and a second opening at the upper portion,

a sensor cartridge mounted for movement in the cavity, between an inserted position and a retracted position, the cartridge defining an elongated opening with an upper end for receiving the sensor probe and a lower end for exposing a sensing end of a sensor probe when in the inserted position,

a gasket configured to contact both the lower portion of the sensor cartridge below the lower end of the elongated sensor opening and a surface of the housing defining the cavity when the cartridge is in the retracted position, thereby providing a liquid-proof, pressure-resistant seal between the sensor cartridge and the housing at their respective lower portions, and

a locking mechanism configured to secure the sensor cartridge in the retracted position;

unlocking the locking mechanism of the sensor assembly by placing a cap, having a longitudinal axis, over the upper portion of the sensor cartridge, and disengaging the locking mechanism by rotating the cap about its longitudinal axis; and

transferring the sensor cartridge from the retracted position to the inserted position thereby exposing the sensing end beyond the first opening of the housing.

9. A method as defined in claim 8, wherein:

the cap defines an inner cavity configured to limit placement of the cap upon the sensor cartridge to selected orientations about its longitudinal axis, and

the upper portion of the sensor cartridge is configured to receive the cap in only the selected orientations.

10. A method as defined in claim 8, further comprising the step of securing the cap to the housing once the sensor cartridge is in the inserted position by rotating the cap about its longitudinal axis.