Double piston pump for administering medication

• US 5,526,962 A
• Filed: 05/10/1994
• Issued: 06/18/1996
• Est. Priority Date: 05/10/1993
• Status: Expired due to Term

• Current Assignee: Medimpex Ets
• Original Assignee: Medimpex Ets
• Inventors: Huggenberger, Heinz
• Primary Examiner(s): Shaver, Kevin P.
• Application Number:
  US08/241,139
• Time in Patent Office: 770 Days
• Field of Search: 222/249, 222/250, 222/275, 222/276, 222/265, 222/409, 222/383, 222/383.1, 417/415, 417/534, 417/535
• US Class Current: 222/276
• CPC Class Codes: A61M 5/1422 with double acting or multiple pistons
• CPC Class Codes: F04B 3/00 Machines or pumps with pistons coacting within one cylinder, e.g. multi-stage
• CPC Class Codes: F04B 9/025 Driving of pistons coacting within one cylinder

Abstract

The device of the invention provides preselected doses of liquid medicine and has a cylinder assembly (1, 2) with a left cylinder (1), a right cylinder (2) and a double piston (4, 5) displaceably mounted in the assembly with a left piston end (4) and a right piston end (5). A coupling links the double piston in a positive and/or frictional manner with a drive unit (15). The device is controlled passively by two automatically closing intake valves (7, 8) and two discharge valves (11, 12). Thereby a continuous flow of liquid medicine 20 out of the medicine container 10 can be generated.

Claims

1. A device for administering doses of liquid medicine of predetermined quantity comprising the combination of

right and left cylinders (1, 2);

a substantially constant speed and force linear drive unit (15);

a double-ended piston (4,

     5) having left and right piston ends displaceably mounted in said left and right cylinders, respectively;

means (6) for coupling said double-ended piston to said drive unit (15); and

a pair each of automatically opening and closing intake valves (7,

     8) and discharge valves (11,

     12) for passively controlling the operation of said device.

2. A device according to claim 1 wherein said valves include

a left intake valve (7) for said left cylinder and a right intake valve (8) for said right cylinder, said intake valves being connectable by an intake line (9a, 9b, 9c) to a medicine container (10),

a left discharge valve (11) for said left cylinder and a right discharge valve (12) for the right cylinder, said discharge valves supplying liquid medicine through a discharge line (13).

3. A device according to claim 2 and including a piston rod (3) rigidly interconnecting said left piston end and said right piston end, said piston ends being displaceable in the same direction in said two cylinders.

4. A device according to claim 3 wherein said means for coupling said double ended piston to said drive unit (15) is mounted on said piston rod (3).

5. A device according to claim 4 wherein said means mounted on said piston rod for coupling said piston to said drive unit (15) includes a drive disk (61).

6. A device according to claim 4 wherein said means mounted on said piston rod for coupling said piston to a drive unit (15) includes a non-rotatable threaded spindle (63), an internally threaded gear (62) engaging said spindle and rotated by said drive unit (15).

7. A device according to claim 3 wherein said intake valves (7, 8) and said discharge valves (11, 12) are elastomeric bodies sealed passively.

8. A device according to claim 1 wherein said drive unit comprises a spindle and a nut threaded on said spindle.

9. A device for administering doses of liquid medicine of predetermined quantity comprising the combination of

right and left cylinders (1, 2);

a drive unit (15);

a double-ended piston (4,

     5) having left and right piston ends displaceably mounted in said left and right cylinders, respectively;

means (6) for coupling said double-ended piston to said drive unit (15);

a pair each of automatically opening and closing intake valves (7,

     8) and discharge valves (11,

     12) for passively controlling the operation of said device; and

means for joining said cylinders, said double-ended piston, and said valves into a pump unit (14) detachably coupled to said drive unit (15).

10. A device according to claim 9 wherein said pump unit consists of injection-molded parts.

11. A device according to claim 9 and including a medicine container containing said liquid medicine for dispensing, and a snap-on cap (18) on said container for irreversibly securing against a patient'"'"'s removal of liquid medicine (20) from said medicine container (10).

12. A device according to claim 9 wherein said double-ended piston includes a piston rod between said piston ends, and wherein said means for coupling said double-ended piston to said drive unit (15) is mounted on said piston rod (3).

13. A device according to claim 9 and including a piston rod (3) rigidly interconnecting said left piston end and said right piston end, said piston ends being displaceable in the same direction in said cylinders.