INCREMENTAL DOSE DISPENSER

• US 3,790,048 A
• Filed: 07/28/1972
• Issued: 02/05/1974
• Est. Priority Date: 07/28/1972
• Status: Expired due to Term

• Current Assignee: Chester M. Zmijewski, Gustav V. Borden, Robert A. Luciano
• Original Assignee: Chester M. Zmijewski, Gustav V. Borden, Robert A. Luciano
• Inventors: Luciano, Robert A., Zmijewski, Chester M., Borden, Gustav V.
• Primary Examiner(s): Reeves, Robert B.
• Assistant Examiner(s): Kocovsky, Thomas E.
• Application Number:
  US05/276,196
• Time in Patent Office: 557 Days
• Field of Search: 222/390,391 128/218R,218A 74/126,128
• US Class Current: 222/390
• CPC Class Codes: A61M 5/31553 without axial movement of dose setting member
• CPC Class Codes: A61M 5/3156 using volume steps only adjustable in discrete intervals, i.e. individually distinct intervals
• CPC Class Codes: A61M 5/31575 using scaling up or down transmissions, e.g. gearbox
• CPC Class Codes: A61M 5/31585 performed by axially moving actuator, e.g. an injection button
• CPC Class Codes: A61M 5/31593 Multi-dose, i.e. individually set dose repeatedly administered from the same medicament reservoir
• CPC Class Codes: Y10T 74/1529 Slide actuator

Abstract

A dispenser is provided for use in conjunction with syringes and is capable of accurate, rapid dispensing of small incremental doses and rapid and convenient refilling of the syringe. The dispenser comprises an elongated plunger for engaging and advancing the piston of the syringe to expell liquid doses therefrom. The plunger is threaded along at least a portion of its longitudinal, peripheral surface. A drive wheel is provided for advancing the plunger; the drive wheel having its peripheral surface divided into alternate threaded sections and longitudinal separating grooves. The threaded sections engage the threaded portions of the plunger advancing the same to rapidly dispense the incremental doses. The longitudinal grooves provide a clearance between the plunger and drive wheel thereby leaving the plunger disengaged for rapid refilling of the syringe.

Claims

1. A dispenser for delivering a controlled dose of liquid from a syringe having a liquid containing cartridge open at one end and a piston for expelling the liquid through the open end of the cartridge, said dispenser comprising:

a. a housing;

b. an elongated plunger, reciprocally mounted on said housing, having means at one end for engaging said piston, and being threaded along at least a portion of its longitudinal peripheral surface;

c. a cylindrical drive wheel for advancing said plunger, rotatably mounted to said housing, said drive wheel being threaded along its peripheral surface, said threads being interrupted by radially spaced grooves cut into the peripheral surface and extending parallel to the axis of said drive wheel and separating said threads into radially spaced threaded sections;

d. said drive wheel being mounted, relative to said plunger, so that it may be rotated to alternatively bRing said threaded sections and said grooves into register with said plunger, the threaded sections when brought into register with said plunger, engaging the threads of said plunger and the grooves when brought into register with said plunger providing a clearance between said drive wheel and said plunger; and

e. actuating means for rotating said drive wheel through at least one threaded section and from registry with one separating groove to registry with any separating groove, thereby advancing said plunger and said piston, said rotation ending with said plunger disengaged from said drive wheel.

2. The dispenser of claim 1 provided with preselecting means for selecting the number of threaded sections through which said actuating means will rotate said drive wheel per actuation.

3. The dispenser of claim 2 wherein said preselecting means comprise:

a limiting pin mounted on said depressible element and projecting therefrom in the direction of depression;

a cylindrical section barrel, rotatably mounted on said housing, and having a face opposing and spaced apart from said limiting pin when said depressible element is in the undepressed state;

said opposing face provided with a plurality of radially spaced bores;

said selection barrel being mounted with respect to said limiting pin so that each of said bores may be selectively brought into register for receiving said limiting pin by rotating said selection barrel, whereby the degree of reciprocal travel of said depressible element is limited by the depth of each bore, each bore having a depth limiting the degree of said depressible element travel to corresponding to a rotation of said drive wheel through a preselected number of threaded sections.

4. The dispenser of claim 1 wherein said actuating means comprise:

a depressible element, reciprocally mounted to said housing;

translating means for translating the reciprocating motion of said depressible means to rotary motion; and

driving means for transmitting said rotary motion to said drive wheel.

5. The dispenser of claim 4 wherein said translating means comprise:

a cam pin mounted on said depressible element and adopting the reciprocal motion thereof;

a cam barrel, rotatably mounted on said housing and having a helical cam way cut therein for receiving said cam pin and, by cam action, converting the reciprocating motion of said cam pin into rotary motion of said cam barrel.

6. The dispenser of claim 5 wherein the transmitting means comprise:

a cam barrel drive shaft, integral with said cam barrel;

a driving element of a two-part ratchet, integral with said drive shaft; and

the driven element of the two-part ratchet, integral with said drive wheel;

said cam barrel, said drive shaft, said driving element, said driven element, and said drive wheel all being coaxially aligned.