US 2138605 A
Description (OCR text may contain errors)
Nov. 29, 1938. R. P. LANDls l BLOOD TRANSFUSION SYRINGE Filed Nov. 16, 1936 INVEITOR I?. I? L andas Patented Nov. 29, 1938 PATENT OFFICE BLOOD* TRANSFUSION SYRINGE? Richard P. Landis, Grass Valley, Calif., assigner to Landis Transfusion Equipment Co., Sacramento, Calif., a corporation of California Application November 16, 1936, Serial No. 111,048
This invention relates generally to a blood transfusion syringe and in particular relates to improvements in the flow control valves of such syringes shown Vin my United States Patent No.
2,057,726, issued October 20th, 1936.
The principal object of the present invention is to provide a syringe cap and valve construction for blood transfusion syringes in which the valves employed are of an improved form, such improved form of valve being inexpensive to manufacture and yet very effective to prevent regurgitation of blood from the recipient to donor during a transfusion.
A further object of this invention is to mount the check valves in the syringe cap in such manner that the valves may be readily removed'for cleaning and sterilization.
A further object of the invention is to produce a simple and inexpensive device and yet one which will be exceedingly effective for the purpose for which it is designed.
These objects I accomplish by means of such structure and relative arrangement of parts as will fully appear by a perusal of the following specification and claims. v
In the drawing similar characters of reference indicate corresponding parts in the several views:
Figure 1 is an elevation, mainly in section, of the valve supporting cap as attached to one end of a standard glass, plunger type, syringe.
Figure 2 is an inner end view of the cap.
Referring now more particularly to the characters of reference on the drawing, the device comprises a relatively thick cap I of suitable material having a tapped skirt 2 for threaded but removable connection with a ring 3 secured to one end of a glass, plunger type, syringe 1I. The engaging faces of the cap I and the inwardly projecting flange 5 of ring 3, are carefully machined so that a tight connection is assured Without the use of a gasket. The syringe plunger is indicated at 6.
The cap I is formed with a pair of spaced, longitudinally extending, cylindrical bores 'I and 8. Oppositely facing check valves are disposed in said bores, the valves being constructed and mounted in the following manner: Each valve is made of soft resilient rubber and comprises a cylindrical body 9 freely open at one end and formed at the other end with converging, self closing and 5o normally closed lips I0. These lips are designed so that they will open apart, to permit of a flow therethrough, only with pressure inside the valve. An annular flange II is formed with and surrounds each valve body at said one end, the bore 55 for each valve being enlarged from the adjacent (Cl. 12S-214) end of the cap as at I2, and to a depth greater than the thickness of the flange, to receive and form a seat for such flange. v
The inward opening valve in bore 'I is the intake valve and is secur-ed in place by means of a collar 5 I3 on the base of the intake i'ltting I4, which is threaded into the outer end of the corresponding enlarged bore I2, and engaging flange Il of the valve, to press the same rmly onto its s eat and prevent any leakage past the'v-alve. The other 10 end of the bore 'I is reduced in diameter, as at I5, and is elptica] to conform to the cross sectional configuration of the lips Ill of the intake valve, so that the extent of opening of the lips is limited. l 15 The valve in bore 8 is disposed oppositeto the other valve and opens outward thus functioning as an outlet valve. 'I'he valve in bore 8 is held in place by means of a ring-nut I6 threaded into the adjacent enlarged portion I2 of the bore and 20 engaging the adjacent flange I I on the valve. An outlet fitting-I1 is threaded into the other end of the bore, to cooperate with the lips of the outlet valve. It is to be noted that the valves are so mounted that the exterior of the lips I0 of the 25 valves are free from engagement with any surrounding part whereby the lips may open and close with the reciprocation of plunger 6, the lips of only the intake valve opening on the intake stroke and the lips of only the outlet valve opening 30 in the compression stroke.
In use, the fitting I4 is connected to the usual tubing leading from the donor while tting I'I is connected to the tubing leading to the recipient. Then, upon reciprocation of plunger 6, the blood 35 from the donor is rst drawn into the syringe through the intake valve and then discharged through the outlet valve into the tubing leading to the recipient. As the lips of the valves are normally closed due to the resiliency of the rub- 40 ber, no blood can regurgitate and it will only ow in the intended direction upon opening of the valves in the desired order, i. e. the intake valve opening on the intake stroke and the outlet valve on the compression stroke. With the compres- 45 sion stroke, the normally closed lips of the intake valve are further sealed due to the pressure on the exterior of said lips.
When the transfusion is finished the syringe cap may be easily disengaged from the syringe, the valves removed and the parts cleaned and sterilized. It is impossible to wrongly replace the valves, since the shape of the valves, relative to their bores or sockets in the cap, is such that the valves can only be mounted in one position.
From the foregoing description it will be readily seen that I have produced such a device as substantially fulfills the objects of the invention as set forth herein. .u
While4 this specication sets forth in detail the present and preferred construction of the device, still in practice such deviations from such detail may be resorted to as do not form a departure from the spirit of the invention, as dened by the appended claims.
Having thus described my invention, what I claim as new and useful and desire to secure by LettersPatent is: Y
l. In a blood transfusion syringe, a syringe barrel, a cap mounted thereon, a pair of separate self contained identical check valve members, said members having tubular bodiesand being provided at one end with resilient normally closed lips, the cap having inlet and outlet passages therethrough to. receive the valve bodies in snug fitting relationship, the inlet passage being arranged to receive one of the valves with its lip facing inwardly and the adjacent end of the inlet passage being restricted in size to allow of restricted separation of the lips; the outlet passage being arranged to receive/the other valve with its lip facing outwardly, and a recipienttube coupling mounted on the cap and having a threaded base screwed into the outerY end of the outlet passage; said base having a recess in its inner end to receive the lips of 4Vthe adjacent valve and of a size to allow of limited opening movement of the lips.
2. In a blood transfusion syringe, a cap on the syringe, a, pair of separate self-contained and identical check valve members of tubular form arranged to allow of an unchecked iiow therethrough from one end only, theY cap having inlet and outlet passages therethrough to receive the check valves, and means formed with the check valves and cap to provide for the mounting of the valves in the passages only in the proper posi-v tions to allow of an unchecked flow of blood into the syringe through the inlet passage and out of the syringe through the outlet passage; said means including an annular flange about each check valve at said one end thereof, an annular seat formed in the inlet passage adjacent its outer end to receive the ange of one valve and an annular seat in the outlet passage adjacent its inner end to receive the flange of the other valve.
f through from one end only, the cap having inlet and outlet Ypassages therethrough to receive the check valves, donor and recipient tube couplings mounted on the cap and communicating with the inlet and outlet passages respectively, an annular ange about each check valve at saidone end thereof, an annular seat in the inlet passage adjacent its outer end to receive the flange of one valve, an annular seat in the outlet passage ad-` jacent its inner end to receive the flange of the other valve, a ring threaded into the cap about the inner end of the outlet passage to engage and clamp the adjacent valve-flange in place, and a threaded base on the inner end of the donor cou-` pling to screw into the outer end of the inlet passage to engage and clamp the adjacent valveflange in place. Y
RICHARD P. LANDIS.