Abstract An adjustable syringe plunger of Teflon and of a size to fit into the cylinder of the syringe and having forward and rearward ends, the plunger being axially tapered externally thereof toward its forward and rearward ends from an annulus adjacent its forward end. The plunger has a threaded axial, cylindrical bore therein extending from its rearward end toward its forward end and terminating in an inner end just rearwardly of the annulus, the plunger having a threaded tapered bore forming an axial continuation of the cylindrical bore and converging from the inner end of the cylindrical bore to adjacent the forward end of the plunger. A stem is threaded through the cylindrical bore and into the tapered bore to expand the plunger in its cylinder, thereby providing a relatively wide band of engagement between the plunger and the cylinder in the area of the annular intersection of the two external axial tapers.
In a syringe having a tubular cylinder, the structure comprising: a. an expansible plunger positioned in and against the cylinder and having forward and rearward ends; b. said plunger being axially tapered externally thereof toward its forward and rearward ends from an annulus adjacent its forward end; c. said plunger having a threaded axial bore therein extending from its rearward end toward its forward end and terminating in an inner end adjacent said annulus; d. said plunger having a threaded tapered bore forming an axial continuation of the bore first mentioned and converging from said inner end of said first-mentioned bore to adjacent said forward end of said plunger; and e. a stem having a threaded end threaded into said firstmentioned bore and threadable into said tapered bore.
Claim 2
Dependent Claim
128 words
In a syringe having a tubular cylinder, the structure comprising: a. an expansible plunger positioned in and against the cylinder and having forward and rearward ends; b. said plunger being axially tapered externally thereof toward its forward and rearward ends from an annulus adjacent its forward end; c. said plunger having a threaded axial bore therein extending from its rearward end toward its forward end and terminating in an inner end adjacent said annulus; d. said plunger having a threaded tapered bore forming an axial continuation of the bore first mentioned and converging from said inner end of said first-mentioned bore to adjacent said forward end of said plunger; and e. a stem having a threaded end threaded into said firstmentioned bore and threadable into said tapered bore.
Claim 3
Dependent Claim
13 words
The syringe structure defined in claim 1 wherein said first-mentioned bore is cylindrical.
Claim 4
Dependent Claim
28 words
The syringe structure set forth in claim 2 wherein the junction of said cylindrical and tapered bores is between said annulus and said rearward end of said plunger.
Claim 5
Dependent Claim
17 words
The syringe structure defined in claim 3 wherein said cylindrical bore is longer than said tapered bore.
Claim 6
Dependent Claim
23 words
The syringe structure defined in claim 3 wherein said cylindrical bore is about two and one-half times as long as said tapered bore.
Claim 7
Dependent Claim
15 words
The syringe structure set forth in claim 1 wherein said plunger is formed of Teflon.