SYRINGE PUMP HAVING A PISTON BRAKE

• US 20090005730A1
• Filed: 09/05/2008
• Published: 01/01/2009
• Est. Priority Date: 01/22/2002
• Status: Active Grant

• Current Assignee: Berthold Wolfram, Hans-Josef Gerlach, Rene Wildner
• Original Assignee: Berthold Wolfram, Hans-Josef Gerlach, Rene Wildner
• Inventors: Wolfram, Berthold, Wildner, Rene, Gerlach, Hans-Josef
• Granted Patent: US 7,823,287 B2
• Time in Patent Office: Days
• US Class Current: 604/67
• 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
• CPC Class Codes: Y10T 29/494 Fluidic or fluid actuated device making
• CPC Class Codes: Y10T 29/49826 Assembling or joining

Abstract

The syringe pump comprises a receiving position for a syringe. The piston plate of the syringe is moved by a drive head which is fastened to a drive rod. For locking the piston rod prior to fixing the piston plate in the drive head, a braking element is provided on a syringe holding head. The syringe holding head further serves for determining the respective syringe size. After placing the syringe holding head against a syringe cylinder, the brake element is actuated to temporarily engage the piston rod and fix it relatively to the syringe cylinder.

Claims

1. A pump for use to pump fluids from a syringe comprising:

a housing comprising a syringe bearing for supporting a syringe cylinder of a syringe, a sensor coupled to a slide for detecting a syringe dimension to determine a size of the syringe, and a motor mounted on the slide and connected to a gear assembly, which is rotatable by the motor;

a rod defining an axis extending from the housing and movable by the gear assembly, said rod having a spring positioned coaxially thereon;

a syringe holding head located at an end of the rod for moving a syringe Inwardly towards the syringe bearing by the spring; and

wherein a brake element is disposed, at least partially, within the syringe holding head and is movable towards the syringe bearing when the motor is activated to rotate the gear assembly, which moves the rod and the brake element.

2. The pump according to claim 1, wherein the syringe bear is in contact with a side of a syringe cylinder.

3. The pump according to claim 2, wherein a linear drive for the brake element extends below the syringe cylinder.

4. The pump according to claim 1, further comprising a cam surface coupled to the slide, said cam surface configured to move a slider plate to receive a flange on the syringe cylinder.

5. The pump according to claim 4, wherein the slide is connected to the syringe holding head by way of a tube.

6. The pump according to claim 1, further comprising a drive head for driving a piston rod in a direction generally orthogonal to the rod.

7. The pump according to claim 6, wherein the drive head comprises a recessed area comprising a sensor.

8. The pump according to claim 7, further comprising a pair of control arms pivotally mounted in said recessed area.

9. The pump according to claim 1, further comprising a slider rod and a slider plate for moving a flange on syringe barrel in an orthogonal direction relative to the rod.

10. The pump according to claim 1, further comprising a pair of guide rails for guiding movement of the slide.

11. A method for using a pump to dispense fluids from a syringe comprising:

backing out a syringe holding head to provide clearance for a syringe comprising a piston rod;

inserting the syringe into a syringe holder and placing a syringe cylinder against a syringe bearing, which is located on a first side of the syringe;

activating a plate to move the syringe cylinder to an axial position relative to a stop wall;

moving a drive head towards a piston plate on the piston rod;

moving a brake element from a second side of the syringe, opposite the first side, towards the syringe bearing to contact the piston rod to delimit axial movement of the piston rod; and

computing a diameter of the syringe.

12. The method of claim 11, further comprising the step of releasing the brake element by moving the brake element radially away from the piston rod.

13. The method of claim 11, further comprising the step of controlling a velocity of the piston rod based, at least in part, on the diameter of the syringe.

14. The method of claim 11, further comprising sensing whether a piston plate is present in the drive head.

15. The method of claim 11, further comprising synchronizing the drive head with the brake element so that the brake element backs away from the piston rod when the drive head moves.

16. A method for making a pump for dispensing fluids from a syringe comprising:

providing a housing with a pair of generally parallel guide rails;

mounting a slide and a motor on the generally parallel guide rails so that the motor and the slide move along the pair of generally parallel guide rails;

placing a rod in mechanical communication with the motor so that rotation of the motor causes the rod to move axially along a parallel path relative to the pair of generally parallel guide rails;

mounting a syringe holding head having a brake element at an end of the rod for holding a syringe barrel;

placing a drive rod generally orthogonally to the pair of generally parallel guide rails and placing a drive head at an end of the drive rod;

said drive head configured to drive a piston rod of a syringe; and

synchronizing the drive head with the brake element so that when the drive head moves by the drive rod, the brake element moves outwardly away from the housing.

17. The method of claim 16, further comprising positioning a slider plate in the housing to axially locate a flange on a syringe barrel relative to the housing.

18. The method of claim 16, further comprising mounting a sensor in the drive head.

19. The method of claim 16, further comprising mounting at least one control arm in the drive head.

20. The method of claim 16, further comprising a handle knob at an end of the syringe holding head.