Automatic injector

• US 6,767,336 B1
• Filed: 01/09/2003
• Issued: 07/27/2004
• Est. Priority Date: 01/09/2003
• Status: Expired due to Fees

• Current Assignee: Sheldon Kaplan
• Original Assignee: Sheldon Kaplan
• Inventors: Kaplan, Sheldon
• Primary Examiner(s): MENDEZ, MANUEL A
• Application Number:
  US10/248,328
• Time in Patent Office: 565 Days
• Field of Search: 604/136, 604/135, 604/134, 604/208, 604/211, 604/131, 604/132, 604/133, 604/137, 604/138, 604/272, 604/274
• US Class Current: 604/136
• CPC Class Codes: A61M 2005/206 With automatic needle insertion
• CPC Class Codes: A61M 2005/2073 preventing premature release, e.g. by making use of a safety lock
• CPC Class Codes: A61M 5/2033 Spring-loaded one-shot injectors with or without automatic needle insertion multishot dosing syringes A61M5/31525, needle insertion only A61M5/3287
• CPC Class Codes: A61M 5/24 Ampoule syringes, i.e. syringes with needle for use in combination with replaceable ampoules or carpules, e.g. automatic ampoules or carpules A61J1/06
• CPC Class Codes: A61M 5/3202 Devices for protection of the needle before use, e.g. caps A61M5/50 takes precedence; for infusion spikes A61M5/1626; protectors for sharps A61B50/3001
• CPC Class Codes: A61M 5/326 Fully automatic sleeve extension, i.e. in which triggering of the sleeve does not require a deliberate action by the user
• CPC Class Codes: A61M 5/3271 with guiding tracks for controlled sliding of needle protective sleeve from needle exposing to needle covering position

Abstract

A first embodiment of an automatic injector employs less material and fewer parts by eliminating an outer housing required in earlier automatic injectors. In a second embodiment, a manually operated sharps protector is provided. In a third embodiment, the sharps protector is deployed by a spring positioned internally of the sharps protector. In a fourth embodiment, the sharps protector is deployed by a spring positioned externally of the sharps protector. In all embodiments, removal of a safety cap enables a user to press on an outer gun sleeve that displaces in an axial direction and releases the trailing end of a spring holder so that a compressed spring that bears against the spring holder unloads and drives a piston that displaces a cannula into the tissue of a user, followed by a liquid medicament injection through the cannula.

Claims

1. An automatic injector, comprising:

a transparent cartridge holder sleeve having a leading end and a an open trailing end;

said leading end having a diameter that does not exceed a diameter of said transparent cartridge holder sleeve;

said cartridge holder sleeve having a lumen;

a cartridge adapted to hold a liquid medicament;

a cannula hub mounted to a leading end of said cartridge;

a cannula mounted to a leading end of said cannula hub;

a piston disposed in trailing relation to said cartridge;

a spacer disposed in trailing and engaging relation to said piston;

a spring holder disposed in trailing and engaging relation to said spacer;

a spring-retaining shoulder formed in said spring holder near a leading end thereof;

said cartridge, piston, and spring holder being slideably received within said lumen;

an inner gun sleeve having a leading end positioned within said lumen, said inner gun sleeve secured to said cartridge holder sleeve at said open trailing end of said cartridge sleeve;

a piston biasing spring under compression having a leading end disposed in abutting relation to said spring-retaining shoulder of said spring holder and a trailing end disposed in abutting relation to a trailing end of said inner gun sleeve;

said trailing end of said inner gun sleeve adapted to releasably engage a trailing end of said spring holder;

said cartridge, piston, spring holder, and cannula being positioned within said lumen in a retracted position when said piston biasing spring is under compression;

said cartridge, piston, and spring holder being positioned within said lumen in an extended position and said cannula extending out of said lumen in leading relation to said cartridge sleeve holder when said piston biasing spring is in repose; and

manually operated releasing means for disengaging said trailing end of said spring holder from said trailing end of said inner gun sleeve so that said piston biasing spring unloads when said releasing means is activated;

said manually operated releasing means including manual displacement of said inner gun sleeve in a trailing-to-leading direction;

a sharps protector movably mounted to said leading end of said cartridge holder sleeve and having a retracted position and an extended position;

said sharps protector being in said retracted position when said cannula of said automatic injector is in a retracted position;

said sharps protector being in said extended position when said cannula is in an extended position;

said sharps protector when in said retracted position having a length sufficient to extend beyond a distal end of said cannula when said cannula is in said retracted position; and

said sharps protector when in said extended position having a length sufficient to extend beyond a distal end of said cannula when said cannula is in said extended position.

2. The automatic injector of claim 1, further comprising:

said spring holder including at its trailing end a plurality of longitudinally-extending, parallel leg members;

said parallel leg members having respective positions of repose where each parallel leg member is parallel to each other leg member of said plurality of parallel leg members;

each of said parallel leg members having sufficient flexibility to enable them to be deflected radially inwardly;

an outer gun sleeve of truncate extent having a radially-inwardly extending detent formed in a leading end thereof;

said inner gun sleeve having a radially-outwardly extending detent disposed in trailing, abutting relation to said outer gun sleeve radially-inwardly extending detent;

a clearance space disposed between said leading end of said outer gun sleeve and a trailing end of said cartridge holder sleeve to enable trailing-to-leading displacement of said outer gun sleeve.

3. The automatic injector of claim 2, further comprising:

a bevel formed in each trailing end of each of said parallel leg members;

a recess formed in each parallel leg member adjacent each bevel in leading relation thereto;

a trailing leg detent are engaged by said inner gun sleeve trailing end;

said trailing leg detent extending into the recess formed in each of said parallel leg members and preventing trailing-to-leading displacement of said parallel leg members when in their respective positions of repose.

4. The automatic injector of claim 3, further comprising:

a central aperture formed in said outer gun sleeve;

a safety cap that engages said outer gun sleeve;

said safety cap having a longitudinally-extending stop member that extends through the central aperture formed in said outer gun sleeve;

said stop member being surrounded by said parallel leg members and said stop member preventing radially-inwardly directed displacement of said parallel leg members;

said parallel leg members being displaceable in a radially-inwardly direction when said safety cap member is removed from said outer gun sleeve.

5. The automatic injector of claim 4, further comprising:

an annular protuberance formed on said outer gun sleeve in surrounding relation to said central aperture on a leading side of said central aperture;

an annular bevel formed in said protuberance;

said annular bevel adapted to slideably engage each bevel formed on the trailing end of said parallel legs when said outer gun sleeve is manually displaced in a trailing-to-leading direction to thereby drive each leg of said parallel legs radially inwardly;

whereby each leg of said parallel legs disengages from said trailing leg detent;

whereby said piston biasing spring unloads and drives said piston and hence said cannula in a trailing-to-leading direction.

6. The automatic injector of claim 1, further comprising:

a sharps protector movably mounted to said leading end of said cartridge holder sleeve and having a retracted position and an extended position;

said sharps protector being in said retracted position when said cannula of said automatic injector is in a retracted position;

said sharps protector being in said extended position when said cannula is in an extended position;

said sharps protector when in said retracted position having a length sufficient to extend beyond a distal end of said cannula when said cannula is in said retracted position; and

said sharps protector when in said extended position having a length sufficient to extend beyond a distal end of said cannula when said cannula is in said extended position.

7. The automatic injector of claim 1, further comprising:

a first diameter-reducing shoulder formed in said cartridge sleeve holder;

said cartridge sleeve holder having a reduced diameter part in leading relation to said first diameter-reducing shoulder;

a sharps protector detent formed in a trailing end of said sharps protector;

a first recess formed in said reduced diameter part of said cartridge holder sleeve, said first recess receiving said sharps protector detent when said sharps protector is in its retracted configuration;

a second recess formed in said reduced diameter part of said cartridge holder sleeve, said second recess disposed in leading relation to said first recess and said second recess receiving said sharps protector detent when said sharps protector is in said extended configuration;

whereby said sharps protector is manually displaceable from engagement with said first recess to engagement with said second recess when said cannula has been displaced from said retracted to said extended position.

8. The automatic injector of claim 7, wherein said sharps protector detent, said first recess, and said second recess are of annular configuration.

9. The automatic injector of claim 1, further comprising:

a first diameter-reducing shoulder formed in said cartridge sleeve holder;

said cartridge sleeve holder having a reduced diameter part in leading relation to said first diameter-reducing shoulder;

a second diameter-reducing shoulder formed in said reduced diameter section of said cartridge holder sleeve in leading relation to said first diameter-reducing shoulder;

said reduced diameter section of said cartridge holder sleeve having a diameter-reducing taper formed in its leading end, said diameter-reducing taper being formed in leading relation to said second diameter-reducing shoulder, and said diameter-reducing taper forming a tapered section of said cartridge holder sleeve;

an internally-mounted sharps protector biasing spring under compression having a lumen that receives said tapered section therein;

said internally-mounted sharps protector biasing spring having a trailing end that abuts said second diameter-reducing shoulder and a leading end that abuts said leading end of said sharps protector;

a first catch formed in said reduced diameter section of said cartridge holder sleeve;

a latch formed in a trailing end of said sharps protector, said latch disposable in releasable engagement with said catch when said sharps protector is in its retracted position;

said latch adapted to be unlatched when said main piston biasing spring unloads and drives said cartridge in a trailing-to-leading direction;

whereby unlatching of said latch releases said latch from said catch so that said compressed sharps protector biasing spring unloads and displaces said sharps protector from said retracted position to said extended position.

10. The automatic injector of claim 9, wherein said first catch includes a pair of diametrically opposed catch members formed in said leading end of said reduced diameter section of said cartridge holder sleeve.

11. The automatic injector of claim 10, wherein said latch includes a pair of diametrically opposed latch members formed in a trailing end of said sharps protector.

12. The automatic injector of claim 11, further comprising:

each of said latch members being separated from said sharps protector along a parting line at a leading end and opposite sides of said latch members;

a trailing end of each of said latch members forming a living hinge with said sharps protector; and

each latch member having a leading end extending into said first catch to prevent unloading of said sharps protector biasing spring;

whereby retraction of each leading end of each latch member from its associated first catch enables unloading of said sharps protector biasing and deployment of said sharps protector to its fully extended position where said deployed cannula is fully housed therewithin.

13. The automatic injector of claim 12, further comprising:

a pair of accommodation slots formed in said reduced diameter section of said cartridge holder sleeve, said accommodation slots being diametrically opposed with respect to one another and each accommodation slot being disposed in spaced apart, leading relation to an associated first catch member;

a pair of radially inwardly biased stop members formed in said sharps protector in diametrically opposed relation to one another, each of said stop members being cut out from said sharps protector along a parting line at a trailing end and opposite sides of each said stop means;

each trailing end of each stop member extending into an associated accommodation slot when said sharps protector biasing spring is under load and said sharps protector is in its retracted position.

14. The automatic injector of claim 13, further comprising:

a second catch formed in said reduced diameter section of said cartridge holder sleeve;

said second catch including a pair of second catch members disposed in diametric opposition to one another;

each of said second catch members being disposed in leading relation to an associated accommodation slot;

said trailing end of each stop member extending into an associated second catch member when said sharps protector biasing spring is unloaded and said sharps protector is in its deployed position, thereby preventing displacement of said sharps protector in a leading-to-trailing direction.

15. The automatic injector of claim 14, further comprising:

first and second guide slots formed in said reduced diameter section of said cartridge holder sleeve in diametrically opposed relation to one another;

first and second detents formed in a trailing end of said sharps protector in diametrically opposed relation to one another;

said first and second detents being slideably received within said first and second guide slots, respectively, when said sharps protector is slideably attached to said cartridge holder sleeve;

said first and second detents abutting a trailing edge of said first and second guide slots, respectively, when said sharps protector is in a retracted position; and

said first and second detents abutting a leading edge of said first and second guide slots, respectively, when said sharps protector in an extended position.

16. The automatic injector of claim 15, further comprising:

a ramp formed in said cartridge holder sleeve, said ramps extending from said tapered section in leading relation to said second diameter-reducing shoulder to said reduced diameter section of said cartridge holder sleeve on the trailing side of said second diameter-reducing shoulder;

said ramp facilitating assembly of said automatic injector;

said radially inwardly biased stop member slideably engaging said ramp when said sharps protector is secure to said reduced diameter section of said cartridge holder sleeve.

17. The automatic injector of claim 1, further comprising:

a first diameter-reducing shoulder formed in said cartridge sleeve holder;

said cartridge sleeve holder having a reduced diameter part in leading relation to said first diameter-reducing shoulder; and

an externally mounted sharps protector biasing spring under compression having a trailing end disposed in abutting relation to said first diameter-reducing shoulder and a leading end disposed in abutting relation to a trailing end of said sharps protector.

18. The automatic injector of claim 17, further comprising:

a first catch formed in said reduced diameter section of said cartridge holder sleeve;

a latch formed in a railing end of said sharps protector, said latch disposed in releasable engagement with said catch when said sharps protector is in its retracted position;

said latch adapted to be unlatched when said piston biasing means unloads and drives said cartridge in a trailing-to-leading direction;

whereby unlatching of said latch releases said latch from said catch so that said externally mounted sharps protector biasing means unloads and displaces said sharps protector from said retracted position to said extended position.

19. The automatic injector of claim 18, wherein said first catch includes a pair of catch members formed in said reduced diameter section of said cartridge holder sleeve in diametric opposition to one another and wherein said latch includes a pair of latch members formed in said sharps protector in diametric opposition to one another.

20. The automatic injector of claim 19, further comprising:

a pair of accommodation slots formed in said reduced diameter section of said cartridge holder sleeve, said accommodation slots being diametrically opposed with respect to one another and each accommodation slot being disposed in spaced apart, leading relation to an associated first catch member;

a pair of radially inwardly biased stop members formed in said sharps protector in diametrically opposed relation to one another, each of said stop members being cut out from said sharps protector along a parting line at a trailing end and opposite sides of each of said stop members;

each trailing end of each stop member extending into an associated accommodation slot when said sharps protector biasing spring is under load and said sharps protector is in its retracted position.

21. The automatic injector of claim 18, further comprising:

a second catch formed in said reduced diameter section of said cartridge holder sleeve;

said second catch means including a pair of second catch members disposed in diametric opposition to one another;

each of said second catch members being disposed in leading relation to an associated accommodation slot;

said trailing end of each stop means extending into an associated second catch member when said sharps protector biasing means is unloaded and said sharps protector is in its deployed position, thereby preventing displacement of said sharps protector in a leading-to-tailing direction.

22. The automatic injector of claim 21, further comprising:

first and second guide slots formed in said reduced diameter section of said cartridge holder sleeve in diametrically opposed relation to one another;

first and second detents formed in a trailing end of said sharps protector in diametrically opposed relation to one another;

said first and second detents being slideably received within said first and second guide slots, respectively, when said sharps protector is slideably attached to said reduced diameter section of said cartridge holder sleeve;

said first and second detents abutting a trailing edge of said first and second guide slots, respectively, when said sharps protector is in a retracted position; and

said first and second detents abutting a leading edge of said first and second guide slots, respectively, when said sharps protector is in an extended position.

23. The automatic injector of claim 22, further comprising:

a ramp formed in said cartridge holder sleeve, said ramp extending from said tapered section to said reduced diameter section of said cartridge holder sleeve;

said ramp facilitating assembly of said automatic injector;

said radially inwardly biased stop member slideably engaging said ramp when said sharps protector is secured to said reduced diameter section of said cartridge holder sleeve.

24. The automatic injector of claim 17, further comprising:

an outer gun sleeve having a first truncate section having a first diameter and a second elongate section having a second diameter greater than said first diameter; and

said second elongate section of said outer gun sleeve having a leading end positioned in at least partially ensleeving relation to said externally-mounted sharps protector biasing spring.

25. The automatic injector of claim 24, further comprising:

a clearance space disposed between said leading end of said first truncate section of said outer gun sleeve and a trailing end of said cartridge holder sleeve to enable trailing-to-leading displacement of said outer gun sleeve;

a safety cap member that slideably receives said first section of said outer gun sleeve;

said second elongate section of said outer gun sleeve disposed in ensleeving relation to said cartridge holder sleeve;

said cartridge holder sleeve having a radially-outwardly extending detent formed therein near a leading end thereof;

a recess formed in said outer gun sleeve for accommodating said radially-outwardly extending detent;

said recess formed in said outer gun sleeve having a longitudinal extent substantially equal to a longitudinal extent of said radially-outwardly extending detent and said longitudinal extent of said clearance space so that the radially-outwardly extending detent is positioned at a leading end of said recess when said piston biasing means is under compression and said radially-outwardly extending detent is positioned at a trailing end of said recess when said piston biasing is not under compression.

26. The automatic injector of claim 17, further comprising:

an outer gun sleeve having a first truncate section having a first diameter and a second elongate section having a second diameter greater than said first diameter; and

said second elongate section of said outer gun sleeve having a leading end positioned in spaced relation to a wailing end of said externally-mounted sharps protector biasing spring in trailing relation thereto so that a pre-firing visual inspection of said liquid medicament is accomplished without looking through said elongate section of said outer gun sleeve.

27. The automatic injector of claim 26, further comprising:

a clearance space disposed between said leading end of said first truncate section of said outer gun sleeve and a trailing end of said cartridge holder sleeve to enable trailing-to-leading displacement of said outer gun sleeve;

a safety cap member that slideably receives said first section of said outer gun sleeve;

said second elongate section of said outer gun sleeve disposed in ensleeving relation to said cartridge holder sleeve;

said cartridge holder sleeve having a radially-outwardly extending detent formed therein near a leading end thereof;

a recess formed in said outer gun sleeve for accommodating said radially-outwardly extending detent;

said recess formed in said outer gun sleeve having a longitudinal extent substantially equal to a longitudinal extent of said radially-outwardly extending detent and said longitudinal extent of said clearance space so that the radially-outwardly extending detent is positioned at a leading end of said recess when said piston biasing spring is under compression and said radially-outwardly extending detent is positioned at a trailing end of said recess when said piston biasing spring is not under compression.

28. An automatic injector, comprising:

a cartridge holder sleeve having a leading end and an open trailing end;

said leading end having a diameter that does not exceed a diameter of said cartridge holder sleeve;

said cartridge holder sleeve having a lumen;

a cartridge adapted to hold a liquid medicament;

a cannula hub mounted to a leading end of said cartridge;

a cannula mounted to a leading end of said cannula hub;

a piston disposed in trailing relation to said cartridge;

a spacer disposed in trailing and engaging relation to said piston;

a spring holder disposed in trailing and engaging relation to said spacer;

said cartridge, piston, and spring holder being slideably received within said lumen;

an inner gun sleeve having a leading end positioned within said lumen, said inner gun sleeve secured to said cartridge holder sleeve at said open trailing end of said cartridge sleeve;

a piston biasing spring under compression having a leading end disposed in abutting relation to said spring holder and a trailing end disposed in abutting relation to a trailing end of said inner gun sleeve;

said trailing end of said inner gun sleeve adapted to releasably engage a trailing end of said spring holder;

said cartridge, piston, spring holder, and cannula being positioned within said lumen in a retracted position when said piston biasing spring is under compression;

said cartridge, piston, and spring holder being positioned within said lumen in an extended position and said cannula extending out of said lumen in leading elation to said cartridge sleeve holder when said piston biasing spring is in repose; and

manually operated releasing means for disengaging said trailing end of said spring holder from said trailing end of said inner gun sleeve so that said piston biasing spring unloads when said releasing means is activated;

said manually operated releasing means including manual displacement of said inner gun sleeve in a trailing-to-leading direction;

a sharps protector movably mounted to said leading end of said cartridge holder sleeve and having a retracted position and an extended position;

said sharps protector being in said retracted position when said cannula of said automatic injector is in a retracted position;

said sharps protector being in said extended position when said cannula is in an extended position;

said sharps protector when in said retracted position having a length sufficient to extend beyond a distal end of said cannula when said cannula is in said retracted position; and

said sharps protector when in said extended position having a length sufficient to extend beyond a distal end of said cannula when said cannula is in said extended position.