US 3662752 A
An infusion device in which a back-flow check valve is provided at an opening communicated with an air and medical fluid injection groove formed along the length of the needle body, said check valve being made of a flexible material such as rubber or soft plastics and having its forward end formed spherically or in other similar configuration, with a slit being formed at the front thereof, and whereby either air or liquid medicine, as the case may be, caused to flow in the injected direction when so desired.
Description (OCR text may contain errors)
1 51 May 16,1972
3,217,711 11/1965 Pecina et 128/214 C  INFUSION DEVICE  Inventor:
S N m T. A w L P P A R O m E T. A P N m 0 F Kousou Yokoyarna, Hiroshima, Japan CCCM 4442 111/ 222 ///2 0088.1 222 [7 3] Assignee: Japan Medical Supply Co., Ltd.,
Hiroshima-K911119111 1,225,859 2/1960 France...  Filed: July 8, 1970 1,464,988 3/1966 France 1, 538,728 8/1941 Great ] App1.No.: 53,102
Examiner-Dalton L. Truluck Primary Foreign Application Priority Data July 12, 1969 Attorney-Lawrence 1. Field .lapan...................................44/65523 2,757,670 8/1956 Ogle...... ...............,...........,128/214 C 3,092,106 6/1963 128/214 C lClaim, 5 Drawing Figures Butler INFUSION DEVICE The present invention relates to an infusion set and more particularly to an infusion device having animproved air and liquid medicine flowing section.
In the courseof a surgical operation, there often arises an occasion when it is desired to mix some other medicine in a liquid medicine or blood during infusing or transfusing of the liquid medicine or blood from a vial or the like by an infusion or transfusion means. Aninfusion device designed to meet such necessity is proposed in corpending Japanese Utility Model Registration Application No. 58,543/68filed on 'July 1 1, 1968 by the same applicant as the present application. The infusion device of the just mentioned application comprises a branched cylinder provided atthebase ofthe sheath of the needle body and in communication with an air injection groove, a check valve providednear the forward end of the fluid through-passage holein said branched cylinder, and a cylindrical structure having an internal taper on its inner wall, whereby during infusion of a fluid medicine'from a-medicine bottle, some other desired medicine may beintroduced into said medicine bottle through-said cylindrical structure and air injection groove and mixed in the main fluid medicine. This infusion device, however, had several serious defects. For instance, the check valve used in the air and'liquid medicine passage is smallin size and is also of a type where the valve body makes mechanical motion, so that such infusion device runs into trouble during use and also couldnot stand long=time use.
The present invention aims at overcoming all of suchdefects and'difficulties involved in the conventional devices, and it is therefore a primary object of the present inventionto provide a novel and'improved medical fluid-infusing instrument characterized by use of a back-flow preventing valve with a simple structure having no mechanicalmovable parts such as have been used in the previously known conventional devices in the air and liquid medicine passage, so as to permit infusion and proper mixing, as desired, of some other additive medicine into the vial of a principal fluid medicine through said air and liquid medicinepassage'during infusionof said principal liquid medicine to a human body from the vial.
It is another object of the present inventionto provide a novel medical fluid infusing instrument which can stand longtime use. i
The above and other objects contemplated by the present invention are accomplished by providing a novel medical fluid infusion instrument comprising: a collecting needlebody having a central hollow for formed longitudinally thereof for passage of liquid medicine and an air and liquid medicine injection groove formed longitudinally in the side wall thereof, a sheath having a branched cylindrical portion which is provided at the bottom of said sheath in communication with said air and liquid medicine injectiongroove and adaptedto sheath or cover said needle body, and a cylindrical structure provided with a back-flow preventing valve consisting of a hollow valve section which is formed spherically or in other similar configuration of a flexible material such as rubber or resin so as to allow passage of air and liquid medicine only in the'direction of injection and which has a slit formed at its front end, and a hollow conduit portion formed of same material asand integrally with said valve section, said cylindrical structure hav ing a configuration to fit with said branched cylindrical portion.
Now, the present invention will be described in more detail by way of its preferred embodiment with reference to the accompanying drawings, in which:
FIGv 1 is a front view partially broken away of a medical fluid infusing instrumentaccording to the present invention;
FIG. 2 is a partial vertical sectional view of the medical fluid infusing instrument of FIG. 1;
FIG. 3 is an enlarged sectional view of a part of said infusing instrument, showing the passage of air and liquid medicine;
FlG. 4a is a front view of a back-flow preventing valve used in the air and liquid medicine passage in the present fluid infusing instrument; and
FIG. 4b'is a sectional view taken along the line 4b- 4bof FIG. 4a'and in the direction of arrows in FIG. 4a.
Referring-first to FIGS. land 2, thereis shown-amedical fluid infusing instrument, generally designated by reference number 1, according to the present invention. :Reference number 2 denotes a fluid collecting needle body which has formed in its center and longitudinally thereof a liquid medicine inlet "5 and an innerlbore 3 forpassage of liquid medicine leading to a bottom end portion 90. At the top end of said needle 'body 2 is planted a needle 7 made of ahard material suchas metal. Denoted byreference-number ti'are thegrooves for passage of liquidmedicine which are formed on both sides of the needle body so as toextend from thetop end of saidneedle body to the liquid'medicine inlet -5. lnthe external wall of said-needle body 2 is forrnedaa'longitudinally extending. air and liquid'medicine injection. groove 4 which is reduced in width and soiarranged that one end ispositioned closer to the top end of the needlebodylthan to theliquid medicine inlet "5. Reference number "10 indicates a sheath covering the entire outerperiphery of the needle body2 except for the opening of the liquidmedicine inlet 5, whereby said air and liquid medicine injection groove 4 is also covered, with only the end thereof beingleft exposed. Said sheath '10 is tapered toward its forward end so that the diameter of said forward end will be substantially .equal tothat of the'needle body. At the base 12 of said sheath is provided a circular socket 13-which is adapted to'receive a'protuberance8 onthe base'9 of the needle body tothereby secure thesheath tothe needle body. Right above the base of said sheath I0 is,provided a protruding branched cylindrical portion 11 arranged to connect to a cylindrical structure 14 which has formed therein an air and liquid medicine a bore 17 communicated 'with the air and liquid medicine injection groove 4. As will be seen-in the drawing (see FIG. 2), the inner wall 16 of the cylindrical structure 14 isgiven a taper so as to fit with a syringe or the like.
ln the center of the inner end of said cylindrical structure 14 is provided a back-flow preventive valve 25 (see FIGS. 4a and 4b) which, asbest shown inFIG. 3, consists of a'hollow valve section 26 formed spherically orin other similar configuration with a flexible material such as rubber or plastic, with a slit 26a'being formed at its front'end, and a hollow conduit portion '27 made of the samematerial as and integrally with said valve section 26. The back-flow preventive valve'25 has an extremely simplestructureas shown and is so constructed that theslit 26a is opened only when the pressure applied to its inner surface is higher than the pressure applied to its outer surface so as to allowpassage of air or liquid medicine in the direction of arrow. Normally, the slit 26a is kept closed to inhibit movement of fluid. Reference number 28 designates a liquiddropping cylinder mounted between the bases9 and 12, and 29a cylindrical element in which a suitable filter means 30 is installed and which is arranged to fit into the cylindrical structure 14.
ln use of the present invention, the pointed end of the needle body 2 is thrust into a rubber plug of a vial or the like in element 29 is provided in the flow passage hole 17 in the cylindrical structure 14, any dust, germs or other undesirable substances mixed in the air are eliminated. Thus, when the pressure exerted by the cleaned air against the inner wall of the back-flow preventing valve 25 exceeds the pressure against its outer wall, the slit 26a is opened to produce an air stream running in the direction indicated by arrow in the drawing. When the pressures given to the inner and outer walls of 'the back-flow preventive valve 25 are equal to each other, 'or
when the pressure against the outer wall is larger than that against the inner wall, said slit 26a is kept closed to inhibit movement of air, so that there is no outflow (back-flow) of air in said vial to the outside of the fluid infusion instrument.
in the course of infusion of a liquid medicine, when it is desired to mix therein some other desired liquid medicine, the filter-attached cylindrical member 29 located in the passage 17 in the cylindrical structure 14 is removed, and instead, a suitable syringe or the like is fitted thereinto whereby to mix a desired medicine into the vial through the same route as the above-said air passage. The internal taper formed on the inner wall of the cylindrical structure 14 facilitates fitting of the syringe or the like thereinto. When other medicine is being mixed into the vial, air injection into said vial is interrupted, but since the positive pressure therein is not excessively reduced by introduction of such other medicine into the vial, there is no need of halting the liquid infusing operation. In this case, the back-flow preventing valve 25 operates in just the same manner as in the case of air injection, so that any back-flow of liquid medicine from the via] to the outside thereof through the air and liquid medicine injection groove 14 is perfectly inhibited.
Thus, according to the fluid infusing instrument of the present invention, it is possible to mix in the liquid medicine, which is being infused, other desired fluid medicine, whenever so desired, quickly and with extreme ease. Particularly, in the present invention, a backflow preventing valve 25 having an extremely simple construction with no mechanical movable parts such as used in the conventional devices is employed in the air and liquid medicine flowing passage in the instrument, so that any possibility of causing serious troubles due to failure of check valve during fluid infusing operation is obviated to ensure safety in operation, and also the instrument can stand long use.
What i claim is:
l. A fluid infusing instrument comprising:
a fluid collecting needle body having a sharpened end and having formed therein a longitudinally extending central bore along the length of said needle body for passage therethrough of liquid medicine, said needle body also having a longitudinally extending air and liquid medicine injection groove formed in the external side wall of said needle body and along the length thereof, both said bore and said injection groove extending parallel to each other, said needle body including a side opening communicating with said bore and located below said sharpened end;
a sheath concentrically mounted on said needle body, extending from a point below said side opening and substantially the remaining length of the needle body, said sheath including a branched cylindrical portion which is located adjacent the bottom of said sheath and which communicates with said air and liquid medicine injection groove;
a hollow valve section consisting of said sheath and a cylindrical structure in said branched cylindrical portion and a back-flow preventive valve formed spherically of a flexible material with a slit being formed at the front end thereof, and a hollow conduit portion made of the same material as and integrally with said valve section and disposed to permit passage of air and liquid medicine only in the direction of injection, said valve being confined within said branched cylindrical portion, whereby air or other desired liquid medicine can be passed, as desired, in the injected direction through said air and liquid medicine injection groove, said back-flow preventive valve and said cylindrical structure.
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