Syringe, specifically for use in medicine

Claim 2

Syringe, specifically for use in medicine, comprising a cylinder provided with an opening at its front end, wherein a plunger is disposed for displacement whose plunger rod projects from the rear end of the cylinder, with provisions for fluid-tight attachment or insertion of a needle, specifically an injection needle or a similar aspiration and/or administration element at or into said opening, characterized by locking means associated with said plunger and/or said plunger rod, which are provided for administration of the (maximum) syringe volume only once, wherein said locking means are provided with check elements interconnected through rated breaking points such that any attempt to overcome a frictional resistance associated therewith will cause them to break off, urging them into an irreversible blocked position detrimental to the function of the syringe.

Claim 3

Syringe according to claim 1, characterized in that a circumferential serration is formed on the envelope of said plunger rod.

Claim 4

Syringe according to claim 1, characterized in that said locking member is designed as a stopping collar whose outer wall bears against the inner wall (25) of said cylinder for displacement therealong and which includes an opening for guided displacement of said plunger rod as well as at least one stopping element in the form of a resilient clamping tongue of metal or a similar springy material whose free end portion is supported and resiliently biased, specifically under the action of spring pressure, on the envelope of the plunger rod at an oblique angle relative to the longitudinal axis of said plunger rod.

Claim 5

Syringe according to claim 3, characterized in that the frictional resistance of said stopping collar (19) at the inner wall of said cylinder is greater than the clamping force exerted by said (metal) clamping tongue onto said plunger rod.

Claim 6

Syring according to claim 1, characterized in that in the area of the rear opening of said cylinder a guide element is disposed whose guiding sleeve is inserted into said cylinder and passes through said plunger rod.

Claim 7

Syringe according to claim 1, characterized in that said check tongue(s), inclusive of said catch, serving as checking element or said clamping tongue serving as checking element is or are connected to the remaining portion of said locking member or said stopping collar, respectively, through a rated breaking location provided specifically in the form of a portion of weakened material.

Claim 8

Syringe according to claim 6, characterized in that with said rated breaking location is associated a radially outwardly extending clearance into said which said checking element or elements associated with said locking member may be urged so as to achieve an irreversible blocking position detrimental to the function of the syringe, whenever said rated breaking location breaks under excessively strong action onto said locking member in opposition to the locking effect produced by said member.

Claim 9

Syringe according to claim 1, characterized in that said plunger rod presents a rated breaking location in the area of its rear end or in the portion facing said manipulator, which breaking location is specifically designed in the form of an indentation extending along the periphery of said plunger rod, wherein said rated breaking location is preferably located within said cylinder with said plunger rod being pushed into the cylinder.

Claim 10

Syringe according to claim 1, characterized in that said locking member is an integral element having clamping tongues (respectively) cooperating with said plunger rod, on the one hand, and the inner wall of said syringe cylinder, on the other hand, such that during the aspiration displacement a locking action will be produced between said locking member, which is caused to follow, and said plunger rod and that during the ejection displacement a locking action will be produced between said locking member, which is fixed in its position in said cylinder, and the cylinder or the inner wall of the cylinder.

Claim 11

Syringe, specifically for use in medicine, comprising a cylinder provided with an opening at its front end, wherein a plunger is disposed for displacement whose plunger rod projects from the rear end of the cylinder, with provisions for fluid-tight attachment or insertion of a needle, specifically an injection needle or a similar aspiration and/or administration element at or into said opening, with locking means being associated with said plunger rod such that the volume of the syringe may be administered only once, characterized in that said locking means is a separate stopping collar through which said plunger rod passes for displacement so as to cause the stopping collar to follow only in the direction of the displacement for aspiration, such that during the ejection motion of said plunger rod said stopping collar will remain in the position into which it was caused to follow during the displacement for aspiration, without impeding said rod, specifically due to the frictional or positive locking effective in the direction of ejection between said stopping collar and the inner wall of said cylinder, on the one hand, while on the other hand, a repeated displacement for aspiration of the plunger rod is blocked due to engagement at said plunger rod.

Claim 12

Syringe, specifically for use in medicine, comprising a cylinder provided with an opening at its front end, wherein a plunger is disposed for displacement whose plunger rod projects from the rear end of the cylinder, with provisions for fluid-tight attachment or insertion of a needle, specifically an injection needle or a similar aspiration and/or administration element at or into said opening, with locking means being associated with said plunger rod such that the volume of the syringe may be administered only once, characterized in that said locking means is a separate stopping collar through which said plunger rod passes for displacement so as to cause the stopping collar to follow only in the direction of the displacement for aspiration, such that during the ejection motion of said plunger rod said stopping collar will remain in the position into which it was caused to follow during the displacement for aspiration, without impeding said rod, specifically due to the frictional or positive locking effective in the direction of ejection between said stopping collar and the inner wall of said cylinder, on the one hand, while on the other hand, a repeated displacement for aspiration of the plunger rod is blocked due to engagement at said plunger rod.

Claim 13

Syringe according to claim 10, characterized in that said stopping collar includes at least one check element in the form of a checking tongue provided with a catch or in the form of a resilient clamping tongue made of metal or similar resilient material.

Claim 14

Syringe according to claim 10, characterized in that said plunger rod has a smooth envelope into which said resilient clamping tongue may penetrate so as to prevent a repeated aspiration displacement of the plunger rod.

Claim 15

Syringe according to claim 10, characterized in that said plunger rod is provided with a circumferential serration for mechanical engagement of said checking tongue(s) or clamping tongue such that a repeated aspiration displacement of said plunger rod will be prevented.

Claim 16

Syringe according to claim 13, characterized in that said serration presents a saw-toothing with teeth of equal tooth profile, with one tooth flank each of said teeth being disposed at an oblique angle relative to the longitudinal axis of the plunger rod and with the respective other tooth flank of said teeth being disposed orthogonally relative to said longitudinal axis of the plunger.

Claim 17

Syringe according to claim 10 characterized in that the movement of said locking member in the direction of the aspiration displacement (x) is limited by a stop in the area of the rear end of said cylinder.

Claim 18

Syringe according to claim 15, characterized in that in the area of the rear opening of said cylinder an anti-withdrawal stop is formed for said locking member, which serves at the same time as a stop to arrest the displacement of said locking member.

Claim 19

Syringe according to claim 16, characterized in that said anti-withdrawal stop is formed as a re-entrant edge of the inner wall of said cylinder, which reduces the area of unrestricted passage of said cylinder.

Claim 20

Syringe according to claim 16, characterized in that said anti-withdrawal stop is designed as a peripheral groove provided in the inner wall of said cylinder for latching engagement of a peripheral flange formed at said locking member.

Claim 21

Syringe according to claim 10, characterized in that in the area of the rear opening of said cylinder a guide element is disposed whose guiding sleeve is inserted into said cylinder and passes through said plunger rod.

Claim 22

Syringe according to claim 10, comprising a manipulator, specifically an operating disk, which is laterally salient at the free end of said plunger rod that projects from said cylinder, characterized in that said manipulator (operating disk) is connected to said plunger rod through a rated breaking line, specifically in the form of a line along which the material is weakened.

Claim 23

Syringe according to claim 10, characterized in that said locking means are provided with check elements interconnected through rated breaking points such that any attempt to overcome the check effect will cause them to break off, urging them into an irreversible blocked position detrimental to the function of the syringe.

Claim 24

Syringe according to claim 21, in that said check tongue(s), inclusive of said catch, serving as checking element or said clamping tongue serving as checking element is or are connected to the remaining portion of said locking member or said stopping collar, respectively, through a rated breaking location provided specifically in the form of a portion of weakened material.

Claim 25

Syringe according to claim 22, characterized in that with said rated breaking location is associated a radially outwardly extending clearance into which said checking element or element associated with said locking member may be urged so as to achieve an irreversible blocked position detrimental to the function of the syringe, whenever said rated breaking location breaks under excessively strong action onto said locking member in opposition to the locking effect produced by said member.

Claim 26

Syringe according to claim 10, characterized in that said plunger rod presents a rate breaking location in the area of its rear end or in its area facing said manipulator, which breaking location is specifically designed in the form of an indentation extending along the periphery of said plunger rod, wherein said rated breaking location is preferably located within said cylinder when said plunger rod is pushed into the cylinder.

Claim 27

Syringe according to claim 10, characterized in that said locking member is an integral element having clamping tongues cooperating with said plunger rod, on the one hand, and the inner wall of said syringe cylinder, on the other hand, such that during the aspiration displacement a locking action will be produced between said locking member, which is caused to follow, and said plunger rod, and that during the ejection displacement a locking action will be produced between said locking member, which is fixed in its position in said cylinder, and the cylinder or the inner wall of the cylinder.

Claim 28

Syringe according to claim 1, comprising a manipulator, specifically an operating disk, which is laterally salient at the free end of said plunger rod that projects from said cylinder, characterized in that said manipulator is connected to said plunger rod through a rated breaking line, specifically in the form of a line along which the material is weakened.

Claim 29

Syringe according to claim 1, characterized in that said locking means are disposed and operative inside said cylinder.

Claim 30

Syringe, in particular according to claim 1, characterized in that said needle specifically injection needle, is permanently fixed by bonding, welding or embedding in the cylinder material in the opening at the front end of said cylinder.

Claim 31

Syringe according to claim 1, characterized in that said locking means are mechanically operatively engaged with said plunger and said plunger rod such that said plunger, having performed a complete ejection stroke either in one stroke completely or gradually, is either blocked for a repeated aspiration displacement or irreversibly moved out of its operative engagement with said plunger rod by a repeated displacement for aspiration.

Claim 32

Syringe according to claim 1 characterized in that said locking means includes a locking member through which said plunger rod passes so as to cause the member to follow only in the direction of the aspiration displacement such that during the ejection displacement of said plunger rod the member will remain in the position into which it was caused to follow during the aspiration displacement, without impeding said rod, specifically due to the frictional or positive locking effective in the direction of ejection between said locking member and the inner wall of said cylinder.

Claim 33

Syringe according to claim 30, characterized in that the displacement of said locking member in the direction of the aspiration displacement is limited by a stop in the area of the rear end of said cylinder.

Claim 34

Syringe according the claims 31 characterized in that the area of the rear opening of said cylinder an anti-withdrawl stop is formed for said locking member which serves at the same time as a stop to arrest the displacement of said locking member.

Claim 35

Syringe according to claim 32, characterized in that said anti-withdrawl stop is formed as a re-entrant edge of the inner wall of said cylinder, which reduces the area of unrestricted passage of said cylinder.

Claim 36

Syringe, in particular according to claim 32, characterized in that said anti-withdrawl stop is designed as a peripheral groove provided in the inner wall of said cylinder for latching engagement of a peripheral flange formed at said locking member.

Claim 37

Syringe, according to claim 30, characterized in that said locking member is designed as a stopping collar whose outer wall bears against the inner wall of said cylinder for displacement therealong and which includes an opening for guided displacement of said plunger rod as well as at least one, preferably two, diametrically opposing locking elements, specifically in the form of resilient check tongues with one catch each, which tongues may be brought into mechanical engagement with a serration extending over part of the length of said plunger rod.

Claim 38

Syringe according to claim 35, characterized in that said serration presents a saw-toothing with teeth of equal tooth profile with one booth flank each of aid teeth being disposed at an oblique angle relative to the longitudinal axis of the plunger rod and with the respectively other tooth flank of said teeth being disposed orthogonally relative to said longitudinal axis of the plunger.

Claim 39

Syringe according to claim 30, characterized in that the frictional resistance developed by said stopping collar at the inner wall of said cylinder is greater than the clamping force exerted on said slanting tooth flanks by said catch of said at least one check tongue.

Claim 40

Syringe according to claim 30, characterized in that said serration is shaped in a rack-type form at a circumferential section of said plunger rod, in particular at diametrical sides of the latter.