Flow sensor system including spring contacts

Patent metadata

Field	Value
Publication number	US-9976883-B2
Application number	US-201615247084-A
Country	US
Kind code	B2
Filing date	Aug 25, 2016
Priority date	Aug 28, 2015
Publication date	May 22, 2018
Grant date	May 22, 2018

Abstract

A flow sensor sub-assembly for sensing flow of a fluidic medicament is disclosed. The flow sensor sub-assembly includes a first spring contact and a second spring contact. The spring contacts are secured to a base that has a circuit for conducting an electrical signal to and from the spring contacts to a microprocessor. The first spring contact is in electrical communication with a first piezo element and the second spring contact is in electrical communication with a second piezo element. The first spring contact has a first contact force against the first piezo element and the second spring contact has a second contact force against the second piezo element, and the first and second contact forces are equivalent. A circuit board for interfacing to a flow sensor having a plurality of piezo elements for transmitting a flow signal indicative of flow of fluidic medicament is also disclosed.

First claim

What is claimed is:

1. A flow sensor sub-assembly for sensing flow of a fluidic medicament comprising:
a flow tube having a flow tube inlet and a flow tube outlet, through which said medicament flows;
a first piezo element arranged at an upstream position of the flow tube and a second piezo element arranged at a downstream position of the flow tube, the first piezo element and the second piezo element are mounted apart a pre-selected distance from each other;
a first spring contact; and
a second spring contact,
wherein each of said spring contacts are secured to a base, wherein said base has a circuit for conducting an electrical signal to and from said spring contacts to a microprocessor, and said first spring contact is in electrical communication with said first piezo element and said second spring contact is in electrical communication with said second piezo element, and said first spring contact has a first contact force against said first piezo element and said second spring contact has a second contact force against said second piezo element, and said first contact force is equivalent to said second contact force.

2. The flow sensor sub-assembly according to claim 1 , wherein the flow tube further comprises an inner flow tube and end fittings for securing the inner flow tube to the end fittings, and the first and second piezo elements are mounted to the end fittings.

3. The flow sensor sub-assembly according to claim 1 , wherein said first spring contact comprises a pair of cantilevered leaf springs, and said second spring contact comprises a pair of cantilevered leaf springs.

4. The flow sensor sub-assembly according to claim 3 , wherein said circuit is provided on a front surface and a rear surface of a PCB board and said first and second spring contacts are resiliently urged against said first and second piezo elements, respectively, when said first and second piezo elements are inserted between each of said pair of cantilevered leaf springs.

5. The flow sensor sub-assembly according to claim 4 , wherein said circuit is formed integrally with a flow sensor housing by injection molding.

6. The flow sensor sub-assembly according to claim 1 , wherein said first piezo element and said second piezo element are annular in shape and encircle the flow tube at each respective mounting point.

7. The flow sensor sub-assembly according to claim 1 , wherein said flow sensor sub-assembly is contained within a flow sensor housing, wherein said flow sensor housing is coupled to a flow sensor base which contains said microprocessor and said circuit includes connecting pins for providing said electrical signal from said flow sensor sub-assembly to said microprocessor within said flow sensor base.

8. The flow sensor sub-assembly according to claim 7 , wherein said flow sensor sub-assembly is disposed after said flow sensor sub-assembly is used to sense the flow of at least one fluidic medicament.

9. The flow sensor sub-assembly according to claim 8 , wherein the flow sensor base is usable with a different flow sensor sub-assembly.

10. A circuit board for interfacing to a flow sensor having a plurality of piezo elements for transmitting a flow signal indicative of flow of a fluidic medicament comprising:
a base comprising a plurality of electrical circuit traces having a first end and a second end;
a first pair of spring contacts for bias and electrical interface with a first piezo element, said first pair of spring contacts are mounted to said first end of said base and in electrical communication with at least one electrical circuit trace;
a second pair of spring contacts for bias and electrical interface with a second piezo element, said second pair of spring contacts are mounted to said second end of said base and in electrical communication with at least one electrical circuit trace; and
a plurality of pins in electrical contact with said plurality of electrical circuit traces,
wherein each of said spring contacts are pre-configured such that the bias against said first piezo element and the bias against said second piezo element are equivalent and said electrical circuit traces are configured such that each of said pins is in electrical communication with a single spring contact.

11. The circuit board according to claim 10 , wherein each pair of spring contacts comprises a pair of cantilevered leaf springs mounted to said base.

12. The circuit board according to claim 10 , wherein said electrical circuit traces are provided on a front surface of said base and said spring contacts extend from a rear surface of said base.

13. The circuit board according to claim 10 , wherein said circuit board is formed integrally with a flow sensor housing by injection molding.

14. The circuit board according to claim 11 , wherein each of said cantilevered leaf springs further include a mound-like protrusion which contacts a surface of said piezo elements.

15. The circuit board according to claim 10 , wherein said circuit board is assembled into a flow sensor housing in at least two orientations and provides transmission of said flow signal from said piezo elements to a microprocessor.

16. The circuit board according to claim 10 , wherein said circuit board is disposed of after said flow sensor is used to sense the flow of at least one fluidic medicament.

17. The circuit board according to claim 10 , wherein after said flow sensor is used to sense the flow of at least one fluidic medicament, the circuit board is usable with a different flow sensor.

18. The flow sensor sub-assembly according to claim 1 , wherein said first spring contact comprises a pair of opposed cantilevered leaf springs engaging an upstream contact point on said first piezo element and a downstream contact point on said first piezo element, and said second spring contact comprises a pair of opposed cantilevered leaf springs engaging an upstream contact point on said second piezo element and a downstream contact point on said second piezo element.

19. The flow sensor sub-assembly according to claim 3 , wherein said first spring contact comprises a bifurcated cantilevered leaf spring engaging said first piezo element, and said second spring contact comprises a bifurcated cantilevered leaf spring engaging said second piezo element.

Assignees

• Crisi Medical Systems Inc

Inventors

• Dekalb Shawn Wayne
• Raptis Mark

Classifications

• A61M5/16804 Primary

  Flow controllers · CPC title

• G01F1/667

  Arrangements of transducers for ultrasonic flowmeters; Circuits for operating ultrasonic flowmeters · CPC title

• G01F15/18

  Supports or connecting means for meters · CPC title

• A61M5/16831

  Monitoring, detecting, signalling or eliminating infusion flow anomalies (low-level float-valves causing cut-off A61M5/40; indicating or recording presence, absence or direction of flow in general G01P13/0066) · CPC title

• G01F15/14

  Casings, e.g. of special material · CPC title