EP0339954A1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Hypodermic syringe
Assignee: SYNTRALL CANADA Inc
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Filing: 1989-04-26
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Granted: —
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Expires: 2009-04-26
Abstract
Abstract There is described a single use disposable hypodermic syringe (10) and a manner for its manufacture. The syringe has a polystyrene barrel (14) and a plunger assembly (11) snuggly mounted for reciprocation therein. A plunger movement-limiting means is provided and comprises a first ratchet track section extending longitudinally of the barrel on its inside wall, a second ratchet track section (16) parallel to and spaced from the first track section and oriented in a direction opposite to the first track, and, a cross-over ratchet track section connecting the first and second track sections, and track engaging click (23) on the plunger assembly. The plunger assembly may be, moved outwardly of the barrel unidirectionally along the first track section to perform a syringe priming stroke; relocated within the barrel unidirectionally along the cross-over track section to the second track; and moved inwardly of the barrel unidirectionally along the second track section, to perform a delivery stroke.
Inventors
- 👤 Anthony Alles
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-23 19:40
CPC Classifications
A; A61; A61M; A61M5/00; A61M5/50; A61M5/5013; A61M5/502; A61M2005/5026
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
128 words
A hypodermic syringe (10) comprising a barrel (14) and a plunger assembly (11) snuggly mounted for reciprocation therein, characterised in that a ratchet track is disposed on one of the inside surface of the barrel and the piston assembly and a cooperating click (23) is disposed on the other of the inside surface of the barrel and the piston assembly, the ratchet track comprising two ratchet track sections (15, 16) each allowing movement of the click in a respective different direction only, whereby, an engagement of the click with the first ratchet section (15), the plunger assembly can move unidirectionally to perform a priming stroke and, on engagement of the click with the second ratchet section (16), the plunger assembly can move unidirectionally to perform a delivery stroke.
Claim 2
Dependent Claim
128 words
A hypodermic syringe (10) comprising a barrel (14) and a plunger assembly (11) snuggly mounted for reciprocation therein, characterised in that a ratchet track is disposed on one of the inside surface of the barrel and the piston assembly and a cooperating click (23) is disposed on the other of the inside surface of the barrel and the piston assembly, the ratchet track comprising two ratchet track sections (15, 16) each allowing movement of the click in a respective different direction only, whereby, an engagement of the click with the first ratchet section (15), the plunger assembly can move unidirectionally to perform a priming stroke and, on engagement of the click with the second ratchet section (16), the plunger assembly can move unidirectionally to perform a delivery stroke.
Claim 3
Dependent Claim
123 words
A disposable hypodermic syringe (10) according to claim 1 in which the first ratchet track section (15) extends longitudinally of the barrel (14) on the inside wall thereof, and the second ratchet track section (16) is parallel to and spaced from the first track section and in which the syringe further comprises a cross-over ratchet track section (17) connecting the first and second track sections, whereby the plunger assembly (11) may be: (a) moved outwardly of the barrel unidirectionally along the first track section to perform a syringe priming stroke; (b) relocated within the barrel unidirectionally along the cross-over track section to the second track; and (c) moved inwardly of the barrel unidirectionally along the second track section, to perform a delivery stroke.
Claim 4
Dependent Claim
45 words
A hypodermic syringe (10) according to claim 1 or 2 in which locating means (25) is positioned between the plunger assembly (11) and the barrel inside surface to provide the snug mounting and to urge the click (23) to engage the ratchet track (15, 16).
Claim 5
Dependent Claim
40 words
A syringe (10) according to claim 3 in which three locating members (25) and uniformly angularly spaced around the plunger assembly (11) about the click (23) and resiliently urged into friction contact with the inside wall of the barrel (14).
Claim 6
Dependent Claim
34 words
A syringe (10) according to any preceding claim in which the click (23) has contact faces located substantially at right angles to one another for engaging the first (15) and cross-over (17) track sections.
Claim 7
Dependent Claim
46 words
A syringe (10) according to any preceding claim in which the plunger assembly (11) comprises a plunger tip (20), a tip retaining member (22) for receiving the tip, a plunger rod (30) and frangible connections (28, 32) between the plunger rod and the tip retaining member.
Claim 8
Dependent Claim
38 words
A syringe (10) according to claim 6 in which the frangible connections comprise a ball (28) extending longitudinally from the tip retaining member (22) and a co-operating ball receiving and retaining member (32) on the plunger rod (30).
Claim 9
Dependent Claim
35 words
A syringe (10) according to claim 6 or 7 in which the click (23) and the locating members (25) are arranged at equal angular spacings about, and extend outwardly of, the tip retaining member (22).
Claim 10
Independent Claim
231 words
A method of assembling a hypodermic syringe comprising a tubular barrel open at both ends and a plunger assembly, the barrel having opposite sense first and second ratchet track sections extending longitudinally of and parallel to each other on the inside wall of the barrel and connected by a cross-over ratchet track section; the plunger assembly comprising a plunger tip, a tip retaining member, plunger rod and means to frangibly connect the tip retaining member and the plunger rod, which connecting means comprise a ball extending longitudinally from the top retaining member and a co-operating ball receiving and retaining member on the plunger rod; a ratchet-like track section engaging click, and barrel inside wall engaging location members, extending from the tip retaining member; and a needle receiving end cap for closing a front end of the tubular barrel, which method comprises the steps of assembling the plunger tip and retaining means into a sub-assembly, introducing the sub-assembly into the barrel through its front end, engaging an inwardly directed first ratchet-like track section with the click means and the barrel inside wall with the locating members to capture the sub-assembly in the barrel, inserting the plunger rod into the tubular barrel from the back end thereof until the ball and its receiving and retaining member engage and lock, and permanently attaching the end cap to seal the front end of the barrel.
Claim 11
Independent Claim
231 words
A method of assembling a hypodermic syringe comprising a tubular barrel open at both ends and a plunger assembly, the barrel having opposite sense first and second ratchet track sections extending longitudinally of and parallel to each other on the inside wall of the barrel and connected by a cross-over ratchet track section; the plunger assembly comprising a plunger tip, a tip retaining member, plunger rod and means to frangibly connect the tip retaining member and the plunger rod, which connecting means comprise a ball extending longitudinally from the top retaining member and a co-operating ball receiving and retaining member on the plunger rod; a ratchet-like track section engaging click, and barrel inside wall engaging location members, extending from the tip retaining member; and a needle receiving end cap for closing a front end of the tubular barrel, which method comprises the steps of assembling the plunger tip and retaining means into a sub-assembly, introducing the sub-assembly into the barrel through its front end, engaging an inwardly directed first ratchet-like track section with the click means and the barrel inside wall with the locating members to capture the sub-assembly in the barrel, inserting the plunger rod into the tubular barrel from the back end thereof until the ball and its receiving and retaining member engage and lock, and permanently attaching the end cap to seal the front end of the barrel.
References Cited (Backward Citations)
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