Applicator

Abstract

A tube having stoppers at both ends and a free piston intermediate the ends. A medicament is disposed in the tube between one of the stoppers and the piston. The piston is adapted to be engaged by a stem inserted in the tube to expel the medicament from the tube.

Description

This invention relates to an applicator for introducing medicaments into body cavities. The term medicaments embraces jellies, pastes and other materials used as contraceptives or medicines for treatment of the body.

Several types of applicators have been employed and in practice but none has proved completely satisfactory from the standpoint of economy and facility of use. For example, one type of applicator requires filling from a supply of medicament prior to application. It is obviously inconvenient to use and further requires cleaning after application.

Another applicator is shown in U.S. Pat. No. 2,619,087 and is a combined package and applicator. There a medicament is disposed in a tube which has a removable closure at one end and a plunger at the other end. The principal difficulty with this applicator is that the plunger must serve the dual purpose of a seal as well as a device for expelling the medicament. As a seal, it must be quite tight but as a plunger, it must have the capacity of moving freely through the tube. The result has been that the plunger is either not airtight or so tight as to render difficult the application of the medicament.

The objective of the present invention has been to provide a disposable applicator which serves as a package for the medicament, the package being airtight while at the same time being adapted for the easy expelling of the medicament into a body cavity.

The objective of the invention is attained by providing a tube for carrying the medicament, the tube having stoppers at its ends to maintain the airtight integrity of the package and the tube having a free piston intermediate its end, the piston confining the medicament to one end of the tube. Associated with the tube is a stem which is insertable in the end remote from the medicament, the stem being engageable with the piston to expel the medicament from the tube. This combination utilizes very tight stoppers to maintain the airtight integrity of the package while utilizing a free, easily slidable piston, for the purpose of expelling the medicament.

Another objective of the invention has been to provide means for preventing the inadvertent ejection of the piston from the tube during application. This objective is achieved in part by making the stem shorter than the tube by at least the thickness of the piston. Further, the end of the tube may be turned in slightly so as to reduce its diameter below that of the piston, thereby providing a constriction beyond which the piston cannot pass.

It has been another objective of the invention to provide, as a stem, a split tube which can be wrapped about the main medicament-carrying tube thereby reducing the package size. The split tube can easily be removed and contracted to a diameter which permits it to easily be slipped into the main tube to serve as a stem for driving the piston. The use of the split tube further minimizes the possibility of an undesirable resistance to the ease of movement of the piston and stem through the tube to effect the expelling of the medicament since it will not become clamped under the pressure of the fingers of the user on a pliant outer tube.

The several objectives and features of the invention will become more readily apparent from the following detailed description taken in conjunction with the accompanying drawings in which:

FIG. 1 is a perspective view of the invention;

FIG. 2 is an elevational view, partly in section illustrating the manner in which the invention is used; and

FIG. 3 is an elevational view partly in section illustrating the condition of the invention after the medicament has been expelled.

Referring to the drawing, the applicator indicated at 10 has five parts. These are the main tube 11, the two tapered stoppers 12 and 13 mounted at each end of the tube to create an airtight seal at each end, the free piston 14 slidably mounted within the tube, and the split tube stem or sleeve 15 which is normally wrapped around the tube as illustrated in FIG. 1.

As illustrated in FIG. 2, a medicament 16 is disposed in one end of the tube 11 and is confined to that end of the tube by the stopper 12 and the piston 14. Preferably that end of the tube has its edge indicated at 18, rounded and turned in slightly so as to form a constriction having a smaller diameter than the piston 14. The constriction precludes the possibility that the piston 14 would inadvertently drop out of the end of the tube during application of the medicament.

The stem 15 is illustrated as a tube which has a longitudinal slit 19. The slit 19 enables the stem to be expanded for wrapping about the main tube 11 as shown in FIG. 1; and the stem can be contracted by overlapping the edges, as shown in FIGS. 2 and 3 for insertion into the end of the main tube 11 to drive the piston toward the opposite end of the tube to expel the medicament. Preferably, the stem 15 is shorter than the tube 11 by an amount approximately equal to the width of the piston 14. Thus, when the applicator is used, sliding the stem 15 until its free end lies flush with the end of the tube 11, as shown in FIG. 3, effects a substantially complete expulsion of the medicament from the tube while leaving the piston lodged in the end of the tube.

It should be understood that other stems might be employed. For example, a tube having an outside diameter slightly less than the inside diameter of tube 11 could be used as a stem and packaged alongside the tube 11 rather than being wrapped about the tube 11.

In operation, the split tube 15 is removed from the main tube 11. The stopper 13 is removed and the split tube is inserted into the tube 11 until the end of the tube 15 engages the piston 14. The stopper -2 at the other end of the tube has been removed immediately prior to applying the applicator to a body cavity. Normally the medicament is quite viscous and will not flow freely from the tube during the brief period that the stopper 12 is removed. The tube is then introduced into the body cavity and the split tube 15 is slid completely into the tube 11 causing the piston 14 to move to the end of the tube 11 as illustrated in FIG. 3, thereby effecting the complete expulsion of the medicament from the tube into the body cavity. Thereafter the complete device can be thrown away.

Claims

What is claimed is:

1. A medicament applicator comprising:

an elongated tube,

a stopper in each end of said tube forming an airtight engagement therewith,

a piston slidably mounted intermediate the ends of said tube,

a medicament disposed between one stopper and said piston, and

means forming a stem which engages said piston to slide said piston toward the end of said tube and effect the expulsion of said medicament, said stem comprising a sleeve having a longitudinal slit throughout its length, said slit sleeve being normally wrapped about the medicament-containing tube and being radially contractable for insertion into said medicament-containing tube to engage said piston.

2. A medicament applicator according to claim 1 in which,

said stem is shorter than said tube by approximately the thickness of said piston.

3. A medicament applicator according to claim 1 in which,

said piston is easily slidable with respect to said tube.

4. A medicament applicator according to claim 1 in which,

the end of said tube containing said medicament is turned in slightly to form a constriction of the diameter less than the diameter of said piston.