DRIVE DEVICE FOR THE LINEAR MOVEMENT OF AN INFUSION SYRINGE PISTON, INFUSION PUMP AND METHOD FOR REPLACING AN INFUSION SYRINGE

• US 20150094665A1
• Filed: 08/07/2012
• Published: 04/02/2015
• Est. Priority Date: 11/30/2011
• Status: Active Grant

• Current Assignee: B Braun Melsungen AG (B. Braun Holding GmbH & Co. KG)
• Original Assignee: B Braun Melsungen AG (B. Braun Holding GmbH & Co. KG)
• Inventors: Wildner, Rene, Gerlach, Hans-Josef, Heitmeiter, Rolf
• Granted Patent: US 9,352,083 B2
• Time in Patent Office: Days
• US Class Current: 604/152
• CPC Class Codes: A61M 2205/3306 Optical measuring means
• CPC Class Codes: A61M 5/1456 with a replaceable reservoir comprising a piston rod to be moved into the reservoir, e.g. the piston rod is part of the removable reservoir
• CPC Class Codes: A61M 5/1458 Means for capture of the plunger flange

Abstract

The invention relates to a drive device for linear movement of an infusion syringe piston of an infusion syringe disposed on an infusion pump comprising a drive head unit including a main bearing means for supporting the infusion syringe piston, a fixing means for securing the infusion syringe piston to the main bearing unit as well as means for triggering the fixing means and comprising an advancing means for the drive head unit including a motor-drivable advancing spindle and a multi-part advancing spindle nut having at least one radially movable nut shell, wherein the drive head unit additionally comprises detecting means for detecting the infusion syringe piston ahead of the main bearing means, the detecting means including a multi-threshold sensor unit comprising an at least two-stage upstream detection means for detecting different positions of the infusion syringe piston ahead of the main bearing means.

Claims

1-14. -14. (canceled)

15. A drive device for linear movement of an infusion syringe piston of an infusion syringe arranged at an infusion pump comprising:

a drive head unit including a main bearing means for supporting the infusion syringe piston, a fixing means for fixing the infusion syringe piston on the main bearing means as well as means for triggering the fixing means; and

an advancing means for the drive head unit including a motor-drivable advancing spindle and a multi-part advancing spindle nut including at least one radially movable nut shell, wherein the drive head unit in addition comprises detecting means for detecting the infusion syringe piston ahead of the main bearing means;

wherein the detecting means includes a multi-threshold sensor unit having an at least two-stage upstream detection means for detecting different positions of the infusion syringe piston before a piston plate of the infusion syringe piston enters into contact with the main bearing means.

16. The drive device according to claim 15, wherein the multi-threshold sensor unit includes at least two sensors to be triggered by means of one single transmitter element, said transmitter element comprising a contact element projecting from the main bearing means.

17. The drive device according to claim 15, wherein the detecting means comprises at least two light barriers which are arranged axially in series within the drive head unit.

18. The drive device according to claim 17, wherein at least either of the two light barriers is a fork light barrier.

19. The drive device according to claim 15, wherein the main bearing means includes a diaphragm plate comprising a transmitter element including a contact element for switching sensors of the multi-threshold sensor unit.

20. The drive device according to claim 15, wherein one single transmitter element of the multi-threshold sensor unit is arranged inside the means for triggering the fixing means.

21. The drive device according to claim 15, wherein one single transmitter element of the multi-threshold sensor unit has a pre-travel of a value between 2 mm and 10 mm before a first stage of the two-stage upstream detection means can be triggered by the single transmitter element.

22. The drive device according to claim 21, wherein the value is 4 mm.

23. The drive device according to claim 15, wherein the drive device includes at least one joint control means operating as a function of the detecting means for automatic radial engagement of the at least one radially movable nut shell at the advancing spindle and for initiating a reference travel of the main bearing means to be carried out by means of the radially engaged advancing spindle nut up to the infusion syringe piston.

24. The drive device according to claim 23, wherein the joint control means comprises a comparator circuit unit for switching holding solenoids.

25. The drive device according to claim 15, wherein the advancing means comprises holding solenoids controllable by means of the detecting means for actuating axially movable sliding sleeves for radially engaging the advancing spindle nut vis-à

-vis the advancing spindle.

26. An infusion pump comprising the drive device according to claim 15.

27. A method for start-up of an infusion syringe on an infusion pump comprising a drive head unit for linear movement of an infusion syringe piston in which at least one radially movable nut shell of an advancing spindle nut is radially disengaged from an advancing spindle of an advancing means for driving the drive head unit so that the drive head unit of a piston plate of the infusion syringe piston can be quickly axially fed by hand and in which for preventing inadvertent bolus administration the piston plate can be detected by a detecting means including a multi-threshold sensor unit and an at least two-stage upstream detection means associated with the drive head unit, before the piston plate enters into contact with a main bearing surface of a main bearing means of the drive head unit, wherein

in a first detecting step the a contact element of the detecting means triggers a first sensor element, thereby the manual feeding of the drive head unit by means of the advancing spindle nut and the advancing spindle being blocked in that the at least one radially movable nut shell is radially engaged on the advancing spindle, wherein then the drive head unit of the piston plate is further fed by motor drive manner via the advancing means,

in a second detecting step the contact element triggers a second sensor element, thereby a motor-driven reference travel of the drive head unit up to the main bearing surface of the main bearing unit being initiated, and

in a third detecting step the motor-driven reference travel is stopped in the course of contact of the piston plate with the main bearing surface and retaining brackets of a fixing means for the piston plate are closed, thereby the piston plate being secured to the main bearing means.

28. The method according to claim 27, wherein the manual infeed of the drive head unit is blocked, before the contact element triggers the second sensor element.

29. The method according to claim 27, wherein the motor-driven reference travel is carried out by way of a defined number of motor steps.