SYRINGE MOVEMENT MECHANISM AND CONTROL SYSTEM THEREFOR

• US 20100145263A1
• Filed: 02/18/2010
• Published: 06/10/2010
• Est. Priority Date: 12/22/2006
• Status: Active Grant

• Current Assignee: Caesarea Medical Electronics, Ltd. (Becton, Dickinson & Co)
• Original Assignee: Caesarea Medical Electronics, Ltd. (Becton, Dickinson & Co)
• Inventors: Barak, Swi
• Granted Patent: US 8,399,823 B2
• Time in Patent Office: Days
• US Class Current: 604/67
• CPC Class Codes: A61M 2205/14 Detection of the presence or absence of a tube, a connector or a container in an apparatus
• CPC Class Codes: A61M 2205/3306 Optical measuring means
• CPC Class Codes: A61M 2205/3317 Electromagnetic, inductive or dielectric measuring means
• CPC Class Codes: A61M 2205/3365 Rotational speed
• CPC Class Codes: A61M 5/1452 pressurised by means of pistons
• CPC Class Codes: A61M 5/1458 Means for capture of the plunger flange

Abstract

A movement and control mechanism for operating a syringe is disclosed. The movement mechanism comprises a rotatable shaft, at least one rod disposed coaxially to the shaft and a plunger associated unit, accommodating the plunger of the syringe and axially translated upon the rotation of the shaft.

An electrical sensor system implemented with the movement mechanism for detecting the plunger of the syringe, during the operation of the mechanism, is further disclosed.

A control system for the movement mechanism, controlling the operation the thereof is disclosed as well.

Claims

1. An electrical sensor system implemented with a movement mechanism for operating a syringe, said system detects the presence of a plunger of said syringe, said system comprising:

[a] at least two coaxially disposed rods 16A and 16B, said rods 16A and 16B are characterized by at least electrically conductive surface, and

[b] a plunger associated unit (PAU) 20, accommodating said plunger of said syringe, said PAU 20 comprising at least;

[1] a fastener 26, accommodating a thumb-rest plate of said plunger;

[2] at least two flanking apertures 24A and 24B, respectively accommodating said at least two coaxially disposed rods 16A and 16B;

[3] a pushably activated cutoff switch 28, said switch 28 is activated/deactivated by said fastener 26;

[4] at least two probes 29A and 29B, said probes 29A and 29B are electrically coupled to the respective electric terminals of said switch 28;

wherein said PAU 20 is slidably translatable along said at least two coaxially disposed rods 16A and 16B;

wherein said at least two probes 29A and 29B dynamicly form an electrical contact with said electrically conductive surface of said rods 16A and 16B, wherein said contact is maintained during a contiguous sliding of the former along said electrically conductive surface of the latter;

wherein upon introduction of said thumb-rest plate of said plunger in-between said PAU 20 and said fastener 26, said cutoff switch 28 is activated/deactivated;

whereas upon removal of said thumb-rest plate of said plunger, said cutoff switch 28 is respectively deactivated/activated;

wherein an interruptible electrical circuit is formed between said rods 16A and 16B whereby allowing continuously detecting the presence of said plunger in said PAU 20 during said slidable translation of the latter along said electrically conductive surface of the former.

2. The electrical sensor system as in claim 1, wherein said fastener 26 is biased by spring 25 towards said PAU 20 acts as a physical means affecting said cutoff switch 28.

3. The electrical sensor system as in claim 1, wherein said presence is a correct positioning of said thumb-rest plate of said plunger in-between said fastener 26 and said PAU 20.

4. The electrical sensor system as in claim 1, wherein the absence of said presence is at least one selected form the group consisting of:

an incorrect positioning, malposition or absence of said thumb-rest plate of said plunger in-between said fastener 26 and said PAU 20.

5. The electrical sensor system as in claim 1, wherein said fastener 26 comprising a downwardly facing lever 26L.

6. The electrical sensor system as in claim 1, wherein said cutoff switch 28 is a pushable knob.

7. The electrical sensor system as in claim 1, wherein said PAU 20 further comprising a PCB plate 27, onto which said cutoff switch 28 and said probes 29A and 29B are mounted.

8. The electrical sensor system as in claim 1, wherein said probes 29A and 29B are biased probes.

16. The movement and control mechanism 10 as in claim 1, further comprising a coupler, said coupler coupling the rotation of said motor with the rotation of said shaft 12.

17. The movement and control mechanism 10 as in claim 1, wherein said at least one rod 16 comprises two rods 16A and 16B disposed coaxially to said shaft 12 and wherein said at least one flanking aperture 24 comprises two flanking apertures 24A and 24B, respectively accommodating said two rods 16A and 16B.

18. The movement and control mechanism 10 as in claim 1, wherein said motor 14 is characterized by an operational rotational speed of about 160 RPM and rotational torque of about 220 mN/m.

19. The movement and control mechanism 10 as in claim 1, wherein said motor 14 is furnished with a planetary gear.

20. The movement and control mechanism 10 as in claim 1, wherein said screw threading is characterized by a helical pitch of about 0.8 mm per revolution.

9. A control system for a movement mechanism operating a syringe, said system comprising:

[a] a plunger associated unit (PAU) 20, accommodating a plunger of said syringe;

[b] a rotatable shaft 12, wherein a rotation of said shaft 12 generates an axial movement of said PAU 20, substantially coaxially to the axis of the longitudinal centerline of said shaft 12;

[c] a magnetic revolution sensor assembly 30, comprising;

[1] a magnetic or ferromagnetic element 34, disposed offset the longitudinal centerline of said shaft 12;

[2] a reed-switch, affected in at least one angular position of said element 34 relatively to said axis of the longitudinal centerline of said shaft 12;

[d] an optical encoder system 50;

[1] at least one source of optical radiation;

[2] at least two optical sensors disposed vis-á

-vis said source;

[3] a perforated disc 55 comprising a plurality of perforations 57 therein, disposed in-between said sensors and said source, wherein a continuous optical path is formed from the former to the latter via said perforations 57, whereas non-perforated portions of said disc 55 obstruct aforesaid path;

[e] a control module, controlling the operation of said movement mechanism, said control module performs a comparative correlation between the counts of events detected by said encoder system 50 and said magnetic revolution sensor assembly 30;

whereby the correctness in said counts and the absence of malfunction of said encoder system 50 or said magnetic revolution sensor assembly 30 is verified.

10. The control system as in claim 9, wherein said control module triggering an alarm or halting the operation of said movement mechanism upon exceeding an accumulative delta in the comparative counts of said events, wherein said delta is about 2 to about 3 counts.

11. The control system as in claim 9, wherein said magnetic revolution sensor assembly 30 further comprising a housing 32.

12. The control system as in claim 9, wherein said magnetic revolution sensor assembly 30 further comprising a housing 32.

13. The control system as in claim 9, wherein said magnetic revolution sensor assembly 30 further comprising a magnetically conductive barrel 36 used to convey or extend the magnetic field of said element 34 towards said reed-switch.

14. The control system as in claim 9, wherein said at least two optical sensors are two optical sensors disposed adjacently to each other, wherein both of said sensors can be illuminated by said source via a single perforation 57 in said disc 55.

15. A movement and control mechanism (MCM) 10 for operating a syringe, said mechanism 10 comprising:

[f] a rotatable shaft 12, said shaft 12 is furnished with a screw threading;

[g] a motor 14 rotationally coupled to said shaft 12;

[h] at least one rod 16 disposed coaxially to said shaft 12, and

[i] a plunger associated unit (PAU) 20, accommodating a plunger of a syringe, said PAU 20 comprising at least;

[1] a fastener 26, accommodating a thumb-rest plate of said plunger;

[2] a central aperture 22, said central aperture 22 is furnished with a respectively matching screw threading, and

[3] at least one flanking aperture 24, said at least one flanking aperture 24 is furnished with a relatively smooth surface for facilitating a contiguous slidable translation therealong;

wherein said rotatable shaft 12 is accommodated within said central aperture 22, thereby the screw threading of the former is operationally interlocking with the respectively matching screw threading of the latter;

wherein said at least one rod 16 is accommodated within said at least one flanking aperture 24;

whereby upon rotation of said motor, an axial translation of said plunger associated unit 20 along said rotatable shaft 12 is achieved.