Dosage device

Abstract

A dosage device has a hollow barrel and a plunger slidable within the barrel, and a plurality of formations provided on the barrel and plunger and cooperating with one another to produce a sound signal, which corresponds to a predetermined dosage of fluid drawn into or displaced from the barrel. At least one of the barrel and plunger formations is configured to have a plurality of spaced-apart segments shaped and dimensioned to improve the quality of the sound signal.

1 . A dosage device, comprising:
 a barrel extending along a longitudinal axis and having an inner surface;   a barrel formation extending circumferentially on the inner surface of the barrel;   a plunger received in and axially displaceable within the barrel; and   a plunger formation provided on an outer surface of the plunger, wherein the barrel formation is formed of a plurality of segments spaced angularly from one another and configured to selectively engage the plunger formation while generating an indicating signal corresponding to a predetermined dosage of fluid drawn into or dispensed from the barrel during axial displacement of the plunger.   
   
   
       2 . The dosage device of  claim 1 , further comprising at least one additional plunger formation spaced axially from the plunger formation at a distance corresponding to the predetermined dosage of fluid drawn into or dispensed from the barrel during displacement of the plunger. 
   
   
       3 . The dosage device of  claim 1 , wherein the at least one of the plunger and barrel formations includes an indent provided on one of the inner and outer surfaces of the barrel and plunger, respectively, the other one of the plunger and barrel formations including a projection, which upon engaging the indent produces the indicating signal. 
   
   
       4 . The dosage device of  claim 3 , wherein the indent is provided on the outer surface of the plunger and the projection is provided on the inner surface of the barrel. 
   
   
       5 . The dosage device of  claim 3 , wherein the indent is provided on the inner surface of the barrel and the projection is provided on the outer surface of the plunger. 
   
   
       6 . The dosage device of  claim 3 , wherein the projection is configured with the plurality of segments each having a cross-section, which is selected from the group consisting of a triangular shape, polygonal shape, semi-circular shape and a combination of these. 
   
   
       7 . The dosage device of  claim 3 , wherein the projection is configured with the plurality of segments spaced angularly at a uniform or nonuniform distance. 
   
   
       8 . (canceled) 
   
   
       9 . The dosage device of  claim 6 , wherein the indent includes a plurality of recesses spaced angularly from one another and each receiving a respective segment of the plurality of segments. 
   
   
       10 . The dosage device of  claim 1 , wherein the plurality of segments each is made from flexible material. 
   
   
       11 . The dosage device of  claim 3 , wherein a width of the indent along the longitudinal axis is larger than a thickness of each of the plurality of segments to allow at least one of the plurality of segments to resiliently flex and create the indicating signal upon engagement thereof with the indent. 
   
   
       12 . (canceled) 
   
   
       13 . (canceled) 
   
   
       14 . The dosage device of  claim 1 , wherein the plunger has an X-shaped cross-section defined by a plurality of legs, at least two of the plurality of legs each having a respective indent facing the inner surface of the barrel and defining a plurality of segments configured to selectively engage one segment associated of the barrel formation to generate the indicating signal. 
   
   
       15 . The dosage device of  claim 14 , wherein the at least two legs of the plunger extend diametrically opposite to one another or at an angle differing from a 180° angle. 
   
   
       16 . The dosage device of  claim 1 , wherein the plurality of segments of the barrel formation includes at least two projections, the plunger formation including at least two angularly spaced lips each configured to engage a respective one of the plurality of barrel segments to produce the indicating signal. 
   
   
       17 . The dosage device of  claim 1 , wherein the barrel has a distal end and a proximal end located axially opposite to the distal end, the proximal end having a flange traversed by the plunger and provided with the barrel formation. 
   
   
       18 . The dosage device of  claim 1 , wherein the indicating signal is selected from the group consisting of an audible signal, pointed impulse to a user's hand and a combination thereof. 
   
   
       19 . A dosage device, comprising:
 a barrel having an inner surface defining a passage, which extends between a proximal and distal ends of the barrel; and   a plunger mounted within the passage and slidable therein between the proximal and distal ends of the barrel to force fluid into and out of the barrel, the outer and inner surfaces of the plunger and barrel being configured to prevent rotation of the barrel and plunger relative to one another.   
   
   
       20 . The dosage device of  claim 19 , further comprising a barrel formation formed on the inner surface of the barrel in a close proximity to the proximal end of the barrel, and a plunger formation provided on the outer surface of the plunger between proximal and distal ends of the plunger, at least one of the plunger and barrel formations having a plurality of segments spaced angularly from one another and configured to selectively engage the other formation while generating an indicating signal corresponding to a predetermined dosage of fluid drawn into or dispensed from the barrel during axial displacement of the plunger 
   
   
       21 . The dosage device of  claim 19 , further comprising a seal provided on the distal end of the plunger and displaceable therewith to prevent flow communication between the proximal and distal ends of the barrel. 
   
   
       22 . The dosage device of  claim 19 , wherein the proximal end of the barrel has a flange provided with an opening, which is coaxial with the passage and provided with a periphery, the periphery of the opening having a recess configured to engage the plunger so that relative rotation between the plunger and barrel is prevented. 
   
   
       23 . The dosage device of  claim 22 , wherein the plunger is provided with a plurality of legs, one of the plurality of legs having a respective free end engaging the recess provided on the periphery of the opening. 
   
   
       24 . The dosage device of  claim 19 , wherein the proximal end of the barrel has a flange provided with an opening, which is coaxial with the passage and traversed by the plunger, a periphery of the opening having a guide extending radially inwards towards and engaging an outer surface of the plunger so that relative rotation of the plunger and barrel is prevented. 
   
   
       25 . The dosage device of  claim 24 , wherein the guide extend axially and terminates close to the proximal end of the barrel, the plunger being provided with a groove configured to receive the guide so that relative rotation of the barrel and plunger is prevented. 
   
   
       26 . The dosage device of  claim 19 , wherein the plunger has a cross-section selected from the group consisting of a polygonal, elliptical, circular and irregular shape. 
   
   
       27 . A dosage device comprising:
 a barrel having an opening at a proximal end that forms an entrance into an interior of the barrel, wherein the opening has an irregular shape;   a first engagement member extending inwardly into the barrel opening;   a plunger received in and axially displaceable within the interior of the barrel;   a second engagement member that is complementary to the first engagement member and is formed as part of the plunger for selectively engaging the first engagement member so as to generate an indicating signal corresponding to a predetermined dosage of fluid drawn into or dispensed from the barrel during axial displacement of the plunger; and   a first locator feature formed as part of the barrel opening and contributing to the irregular shape thereof, wherein the plunger is configured to mate with the first locator member so as to prevent rotation of the plunger and barrel with respect to one another.   
   
   
       28 . The dosage device of  claim 27 , wherein the first engagement member comprises one or more flexible flanges that extend inwardly into the barrel opening. 
   
   
       29 . The dosage device of  claim 28 , wherein there is a plurality of flexible flanges spaced circumferentially about the barrel opening and the second engagement member comprises a notch whereupon the engagement of one flexible flange within one notch produces the indicating signal. 
   
   
       30 . The dosage device of  claim 27 , wherein the first locator feature is located opposite the one first engagement member. 
   
   
       31 . The dosage device of  claim 27 , wherein the first locator feature comprises a recess that opens into the barrel opening and extends radially outward therefrom and the plunger includes a second locator feature in the form of a projection that is received within the recess. 
   
   
       32 . The dosage device of  claim 27 , wherein the first locator feature comprises a guide member that projects radially inward into the barrel opening and the plunger includes a second locator feature in the form of an axial groove formed longitudinally along a length of the plunger and configured to receive the guide member. 
   
   
       33 . The dosage device of  claim 27 , wherein the irregular shape of the barrel opening is defined by an arcuate portion and an irregular portion, with the locator feature being formed in the irregular portion. 
   
   
       34 . A dosage device comprising:
 a barrel having an opening at a proximal end that forms an entrance into an interior of the barrel;   a plurality of first engagement members extending inwardly into the barrel opening, the first engagement members being circumferentially spaced apart from one another about the barrel opening and arranged in an asymmetric manner;   a plunger received in and axially displaceable within the interior of the barrel;   a second engagement member that is complementary to one first engagement member and is formed as part of the plunger for selectively engaging the first engagement member so as to generate an indicating signal corresponding to a predetermined dosage of fluid drawn into or dispensed from the barrel during axial displacement of the plunger.   
   
   
       35 . The dosage device of  claim 34 , wherein the barrel opening has an irregular shape and the device further includes:
 a first locator feature formed as part of the barrel opening and contributing to the irregular shape thereof, wherein the plunger is configured to mate with the first locator member so as to prevent rotation of the plunger and barrel with respect to one another.