LIQUID WARMING DEVICE WITH BASIN DETECTION

• US 20090014547A1
• Filed: 09/19/2008
• Published: 01/15/2009
• Est. Priority Date: 08/24/2004
• Status: Active Grant

• Current Assignee: Ecolab USA Incorporated (Ecolab, Inc.)
• Original Assignee: C Change Surgical LLC
• Inventors: Kammer, Patrick, Rackers, Kevin Joseph
• Granted Patent: US 8,138,454 B2
• Time in Patent Office: Days
• US Class Current: 236/1.C
• CPC Class Codes: A61B 2050/0018 Electric heating
• CPC Class Codes: A61B 46/10 specially adapted for instruments, e.g. microscopes
• CPC Class Codes: G05D 23/1909 whose output amplitude can only take two discrete values
• CPC Class Codes: G05D 23/1931 to control the temperature of one space
• CPC Class Codes: G05D 23/20 with sensing elements having variation of electric or magnetic properties with change of temperature G05D23/13 takes precedence
• CPC Class Codes: G05D 23/22 the sensing element being a thermocouple

Abstract

A liquid warming device for heating sterile fluids in a removable basin is described with emphasis on the properties of the basin interaction with the liquid warming device and with a drape that works with the basin to maintain a sterile field above the drape and the top of the basin. Also disclosed are various desirable aspects for a control system for a liquid warming device.

Claims

1. A liquid warming device comprising:

a cavity adapted to receive a portion of a removable basin, the removable basin having a bottom, a set of at least one side wall connected to the bottom of the removable basin so that the set of at least one side wall forms a walled perimeter around the bottom of the removable basin to form a container suitable for holding a fluid;

a heater adapted to provide heat through a thermally conductive path to the fluid placed in the removable basin; and

a fluid temperature controller controlling a flow of energy provided to the heater so as to prevent the heater from operating without a positive indication of a presence of an appropriate removable basin.

2. The liquid warming device of claim 1 wherein the positive indication is received from a limit switch that is actuated by an insertion of an appropriate removable basin into the cavity.

3. The liquid warming device of claim 2 wherein the limit switch is implemented with an actuator that moves in a horizontal manner as an appropriate removable basin of varying width moves up and down.

4. The liquid warming device of claim 2 wherein the limit switch is implemented to interact with a known geometry of an appropriate removable basin so that the limit switch is closed by an insertion of an appropriate removable basin into the cavity.

5. The liquid warming device of claim 4 wherein the limit switch is open:

A) if there is not a an appropriate removable basin in the cavity;

or

B) if an appropriate removable basin is placed adjacent to the limit switch but the known geometry of the appropriate removable basin is not placed adjacent to the limit switch.

6. The liquid warming device of claim 5 wherein an appropriate removable basin with a thermocouple well placed in the cavity so that the thermocouple well is not in its intended position will cause the limit switch to be in an open state as the known geometry of the bottom of the appropriate removable basin in the vicinity of the thermocouple well is not positioned adjacent to the limit switch.

7. The liquid warming device of claim 4 wherein the liquid warming device provides an indication to users when the limit switch detects an object but the limit switch is not interacting with the known geometry of an appropriate removable basin and thus the limit switch is open.

8. The liquid warming device of claim 2 wherein a distal end of a fluid temperature sensor used to obtain a temperature from a surface of an appropriate removable basin moves when contacted by the appropriate removable basin so as to close the limit switch.

9. The liquid warming device of claim 2 wherein a limit switch actuator is placed adjacent to a portion of a fixed fluid temperature sensor used to obtain a temperature from a surface of an appropriate removable basin.

10. The liquid warming device of claim 2 wherein the limit switch has an actuator positioned so as to surround a portion of a fluid temperature sensor so as to insulate the fluid temperature sensor from heat flowing from the heater to the fluid temperature sensor without passing into the fluid in the appropriate removable basin.

11. The liquid warming device of claim 2 wherein the limit switch has an actuator placed so that interaction between the limit switch actuator and the appropriate removable basin is remote from the interaction between a fluid temperature sensor and a portion of the surface of an appropriate removable basin.

12. The liquid warming device of claim 1 wherein the fluid temperature controller prevents the heater from operating without a positive indication from a radio frequency identification sensor that an appropriate radio frequency identification tag is in proximity to the radio frequency identification sensor.

13. The liquid warming device of claim 1 wherein the fluid temperature controller prevents the heater from operating unless the fluid temperature controller has both:

A) a positive indication from a radio frequency identification sensor that an appropriate radio frequency identification tag is in proximity to the radio frequency identification sensor; and

B) a positive indication received from a limit switch that is actuated by the insertion of an appropriate removable basin into the cavity.

14. The liquid warming device of claim 1 wherein the positive indication of the presence of an appropriate removable basin is detection of a downward force that may indicate the weight of an appropriate removable basin containing at least a particular minimum volume of a fluid expected to be placed in the removable basin.

15. The liquid warming device of claim 1 wherein the fluid temperature controller controlling the flow of energy provided to the heater so as to prevent the heater from operating without a positive indication of the presence of an appropriate removable basin is adapted to stop preventing the flow of energy to the heater:

while receiving a positive indication of the presence of a downward force that may indicate the weight of an appropriate removable basin with at least a particular minimum volume of a fluid expected to be placed in the removable basin;

until the volume of fluid in the removable basin is decreased sufficiently so that the fluid temperature controller ceases to receive a positive indication of the downward force that may indicate the weight of an appropriate removable basin with at least a particular minimum volume of a fluid expected to be placed in the removable basin.

16. The liquid warming device of claim 1 wherein the lack of a positive indication of the presence of a downward force that may indicate the weight of an appropriate removable basin with at least a particular minimum volume of a fluid expected to be placed in the removable basin activates an alarm to note the fluid temperature controller is preventing the flow of energy to the heater.

17. The liquid warming device of claim 1 wherein the positive indication of the presence of an appropriate removable basin is an affirmation provided by a user through an input device in communication with the liquid warming device that a removable basin and an adequate level of fluid are present.