JP2008284177A - Needleless syringe - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a needleless syringe of a small impact sound type executing suction or injection of liquid medicine by a gas pressure. <P>SOLUTION: A second grip 4, in its inside, is formed with a diaphragm 4c having a gas communication hole 4b, a chamber lid 5 is threadedly attached to the rear end to define its internal space as a gas chamber and a front space of the diaphragm 4c as a cylinder 4g, and the cylinder 4g is disposed with a pressure receiving piston 8 connected to a piston 9 and slidably moving the internal circumferential face in its inside. The chamber lid 5 is fixed with an injection button 14 connected to a communication hole opening/closing rod 15 for opening/closing the gas communication hole 4b. The cylinder 4g is formed with a channel 4d, the gas chamber 6 is formed with a channel 4f, and a channel switch 12 for opening/closing or connecting the channels 4d and 4f is provided. A liquid medicine vial is mounted on a nozzle 2 of the first grip 3, the first grip 3 is advanced to suck the liquid medicine, the injection button 14 is pushed to move high-pressure gas prestored in the gas chamber 6 to the inside of the cylinder 4g, and the pressure receiving piston 8 is pressurized and advanced to inject the liquid medicine. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a needleless syringe that performs injection by jetting a predetermined amount of a chemical solution sucked from an injection hole of a nozzle or a chemical solution previously filled in a nozzle.

  A needleless syringe pushes a chemical solution in a nozzle that has been inhaled from the injection hole at the tip of the needle, or a chemical solution that has been filled in the nozzle with a piston, and jets the drug solution from the injection hole, so that the chemical solution is delivered to the patient (other than human) Syringes). In other words, injection with a needleless syringe does not use an injection needle, so there are advantages such as prevention of needle stick accidents and ease of use for patients with advanced phobia. For example, when a diabetic patient himself self-injects insulin on a daily basis. Is also used. In addition, it has been announced that it is used for gene drugs and has higher medicinal properties than syringes with needles.

  In a conventional needleless syringe, a type in which a piston 32 in a nozzle 31 having a structure as shown in FIG. 7 is advanced at high speed using a compression spring 33 as a power source is often used (see Patent Document 1). This needleless syringe performs injection by releasing a latch mechanism 36 for latching or releasing a first (front) grip 34 in which a nozzle 31 having an injection hole 31a is incorporated, a piston rod 35 to which a piston 32 is connected, and releasing the latch. A second (rear) grip 38 incorporating the injection button 37 is screwed with a screw portion 39. A screw portion 40 is provided at the front portion of the piston rod 35, and a nut 41 for adjusting the injection force of the chemical liquid by adjusting the compressive force is screwed thereon. Further, a flange ring 42 is fixed integrally at the tip thereof. A compression spring 33 is attached between the nut 41 and the rear inner wall of the second (rear) grip 38 through a piston rod 35.

  When the second (rear side) grip 38 of the needleless syringe is rotated and advanced, the latch mechanism 36 latches the piston rod 35 and compresses the compression spring 33, and this compression force causes the piston rod 35 to move forward. Exercise power is energized. In this state, the nozzle 31 is brought into contact with a drug solution vial (not shown), and the second (rear) grip 38 is retracted to suck the drug solution. Then, when the injection button 37 is pushed while the nozzle 31 is pressed against the injection site to release the latch of the piston rod 35, the compression spring 33 is extended, the piston 32 is advanced, and the liquid medicine is injected.

Further, as a needleless syringe, a needleless pressure syringe that presses and drives a piston using a high-pressure gas instead of compressing a compression spring and driving a piston is often used. In conventional high-pressure gas needle-less pressure syringes, carbon dioxide gas is usually enclosed in a small cylinder under high pressure and incorporated in the second grip, and a method of taking out sufficient gas pressure to pressurize the chemical from there. Used (see Patent Document 2).
JP 2003-79725 A JP 2005-261855 A

The conventional needleless syringe is configured as described above. However, when a compression spring is used, an operation for compressing the compression spring is required every time injection is performed, which is troublesome. In addition, the latch mechanism for compressing the compression spring is complicated, requiring labor and cost for manufacturing, and the compression force can be adjusted by the compression spring, but the adjustment range is narrow. Furthermore, when releasing the force of the compression spring, there is a problem that a large impact sound is generated from the latch mechanism and surprises the user and the patient. Further, in the needle-less pressure syringe using the small cylinder as described above, a predetermined amount of gas is used up to pressurize the chemical solution at each injection, and it takes time to secure or replenish the high-pressure gas source. There is.
The present invention has been made in view of such circumstances, and an object of the present invention is to provide a needleless syringe that can be easily operated with a simple configuration, has a small impact sound, and can easily supply gas.

In order to achieve the above object, the needleless syringe of the present invention is a needleless syringe that performs subcutaneous injection by pressing a drug solution with a piston biased by gas pressure and jetting it from an injection hole.
A first grip having a nozzle for injecting the chemical solution and a partition that is threadedly engaged with the first grip and has a communication hole that communicates with the front and rear are formed. A second grip in which a gas chamber is formed by screwing a lid member, a communication hole opening and closing means for opening and closing the communication hole, a high pressure gas supply means for supplying high pressure gas to the gas chamber, and a piston A pressure receiving piston that receives the high-pressure gas supplied from the communication hole and slides in the cylinder, and a first flow path that communicates with a space formed by the pressure receiving piston and the first grip in the cylinder. A second flow path communicating with the gas chamber; a communication between the first flow path and the second flow path; an opening of the first flow path to the atmosphere; a closing of the second flow path; Is obtained by a channel switching means to be switched to three states of the atmosphere opening of the second channel and the closing of the first flow path.

  Further, the communication hole opening / closing means passes through an injection button including a fulcrum forming member provided on the outer surface of the lid member and a lever attached to the fulcrum, and a through hole formed in the lid member, and the communication hole is connected to the front end. A communication hole opening / closing rod that forms an opening / closing part that opens and closes the hole, and a rear end is engaged with the lever; a spring that is wound around the communication hole opening / closing rod and applies a forward biasing force to the communication opening / closing rod; The seal member includes a seal member that is fitted into the through hole to seal between the through hole and the communication hole opening / closing rod, and a seal member that is attached to the open / close region to seal between the communication hole and the opening / closing region. .

  The flow path switching means is connected to the first flow path and the second flow path, and is formed with a first outer peripheral groove connected to the first flow path and a second outer peripheral groove connected to the second flow path. A flow path connecting the first outer peripheral groove and the second outer peripheral groove is formed, and the first flow path and the second flow path are communicated with each other by fitting and sliding on the connection member, and It is composed of a flow rate change-over switch that switches between three states of opening the first flow path to the atmosphere and closing the second flow path, and closing the first flow path and opening the second flow path to the atmosphere.

  The high-pressure gas supply means includes a manual pressure control valve that controls the pressure of the high-pressure gas from the high-pressure gas source to a preset pressure corresponding to the injection site, and a stop valve that turns on and off the supply of the controlled high-pressure gas. And a joint provided on the lid member.

Since this needleless syringe uses high-pressure gas as the driving force for chemical injection and suction, it requires a complicated mechanism and operation to compress the spring and latch the piston rod like the conventional needleless syringe of the spring compression method. Since the number of parts is smaller than that of the spring compression method, it can be manufactured at a low cost, and since there is no compression spring holding mechanism, the sound during launching is quiet. Injection can be performed simply by opening and closing the high-pressure gas supply with the injection button.
In addition, since the high-pressure gas supplied from the outside is used as a power source, the injection force can be changed only by changing the gas pressure, the adjustment range of the injection force can be widened, and it can be used for a wide range of applications.
Furthermore, this needleless syringe can also perform high-pressure gas inhalation of drug solution, so the operation of operating the front and rear grips to compress the compression springs and inhaling the drug solution for each injection is omitted. It is very convenient to save the labor for repeated injections.

Embodiments of the needleless syringe of the present invention will be described with reference to the drawings. FIG. 1 is a longitudinal sectional view of a needleless syringe 1 according to an embodiment of the present invention and a configuration diagram of its power source.
The needleless syringe 1 sucks a chemical solution, screwes a nozzle 2 having an injection hole 2a for injecting the chemical solution and a hollow hole 2b for storing the inhaled chemical solution into the tip, and is located in the vicinity of the middle in the axial direction. A first grip 3 having a screw 3a formed on the outer peripheral surface and grooves 3b and 3c for fitting packings 3A and 3B for high-pressure gas seals formed on the rear outer peripheral surface and the inner peripheral surface; 3 is formed on the inner peripheral surface of the tip, and a partition wall 4c through which the gas communication hole 4b is penetrated at the rear side and flow paths 4d and 4f communicating with the outside are formed on the front and rear sides of the partition wall 4c. A second grip 4 having a gas chamber 6 for storing a high-pressure gas by screwing a chamber lid 5 used as a lid member to a rear portion with a screw portion 25 to store a high-pressure gas, and the inside of the cylinder 4g. From the gas chamber 6 A chemical pressure pressing tool 11 formed by connecting a pressure receiving piston 8 fitted with a packing 7 that moves back and forth while sealing a high-pressure gas to be supplied, and a piston 9 that presses the chemical liquid with a piston rod 10, and the flow paths 4d and 4f. It is comprised from the flow-path switching device 12 which connects and connects and opens and closes the flow path.

  The flow path switch 12 includes a connecting member 12A that forms flow paths 12a and 12b that connect an axial flow path and an outer peripheral groove, a joint 12B that connects the flow path 4d and the flow path 12a, and the flow The joint 12C for connecting the path 4f and the channel 12b, and the sliding member 12A on the connecting member 12A are slid while pushing the latch 4A on the second grip 4. It is comprised from the flow-path switch 12D which connects 12b and opens / closes the flow path 12a or 12b.

  When the flow path changeover switch 12D is in the intermediate position, the cylinder 4g and the gas chamber 6 communicate with each other via the flow paths 4d and 12a, the flow path changeover switch 12D, and the flow paths 12b and 4f. The gas chamber 6 is opened to the atmosphere via the flow paths 4f and 12b, and the flow path 12a is closed by the flow path switch 12D. When the flow path changeover switch 12D is in the rear position, the cylinder 4g is opened to the atmosphere via the flow paths 4d and 12a, and the flow path 12b is closed by the flow path changeover switch 12D.

  A gas cylinder 21 equipped with a manual pressure control valve 19 and an outlet pressure gauge 20 is connected to the stop valve 22 at the rear of the chamber lid 5, and a high-pressure gas tube 23 that is connected to the stop valve 22 and delivers high-pressure gas. The joint 13 to be connected, the injection button 14 for starting the injection of the chemical solution, and the fulcrum forming member 18 forming the fulcrum 18a of the rotation operation of the injection button 14 are fixed.

  Further, the chamber lid 5 has a communication hole opening / closing rod 15 for opening and closing the gas communication hole 4b passing through the central axis thereof, and a portion protruding to the outside is engaged with the injection button 14, and is attached to the tip portion. A stepped circular portion 15a is formed, and a disk-shaped gasket 16 is fixed to the front surface thereof. A rod seal gasket 17 is fitted to the inner wall of the through portion of the chamber lid 5 in order to prevent high pressure gas from leaking outside through the gap between the communication hole opening / closing rod 15 and the through hole of the chamber lid 5. The communication hole opening / closing rod 15 is provided with a compression spring 15 </ b> A between a tip-side stepped circular portion 15 a and the inner wall of the chamber lid 5. When the injection button 14 is not pressed, the communication hole opening / closing rod 15 is pushed forward by the forward biasing force of the compression spring 15A to close the gas communication hole 4b. A rearward force is applied to the communication hole opening / closing rod 15 via 18a, the communication hole opening / closing rod 15 moves rearward, and the gas communication hole 4b is opened.

  An operation procedure for inhaling and injecting a drug solution by the needleless syringe 1 and operations of each part accompanying this operation will be described below with reference to operation explanatory diagrams of the needleless syringe 1 in FIGS. In addition, in each figure, the component shown with the same code | symbol as FIG. 1 has the same function as FIG. 1, and detailed description is abbreviate | omitted. The stop valve 22 shown in FIG. 2 is closed, and the manual pressure control valve 19 is adjusted so that the outlet pressure gauge 20 becomes a predetermined injection pressure. Next, the flow path switch 12D of the needleless syringe 1 is moved to the rear side, and the flow path 12b connected to the gas chamber 6 is closed. After the drug solution vial 24 as shown in FIG. 3 is attached to the tip of the nozzle 2 of the needleless syringe 1, the first grip 3 has a predetermined drug solution amount on the scale 3 d with the second grip 4 held and fixed. Rotate forward to position. At this time, the pressure receiving piston 8 does not move due to the tight contact of the packing 7 on the inner wall of the cylinder 4g and the backward biasing force due to the negative pressure generated at the rear of the pressure receiving piston 8 with respect to the forward movement, as shown in FIG. A space is created in the hollow hole 2b of the nozzle 2, and the chemical solution in the chemical solution vial 24 is stored. Then, the chemical vial 24 is removed from the nozzle 2, the stop valve 22 is opened, and high pressure gas is supplied into the gas chamber 6 to complete the preparation for injection.

  When the tip of the needleless syringe 1 is pressed against the injection site and the injection button 14 is pushed, the communication hole opening / closing rod 15 is retracted and the gas communication hole 4b is opened as shown in FIG. Since the gas presses the pressure receiving piston 8 through the gas communication hole 4b and the air in the cylinder 4g is discharged to the atmosphere via the flow path 4d, the piston 9 and the piston rod 10 are interlocked with the pressure receiving piston 8. The fluid advances smoothly at a high speed, presses the chemical liquid in the nozzle 2, and the chemical liquid is jet-injected at a high speed from the injection hole 2a and injected into the injection site. Even after the injection is finished and the injection button 14 is released, the pressure in the gas chamber 6 remains high because the pressure in the gas chamber 6 remains high.

  When the same amount of drug solution is inhaled by the needleless syringe 1 and repeated injections are performed, after the first injection, the flow path switch 12D is moved to the intermediate position as shown in FIG. Thereby, the flow paths 12 a and 12 b in the flow path switching device 12 communicate with each other, and the high pressure gas is also filled in the front portion of the pressure receiving piston 8 via the flow path 4 d of the second grip 4. In this state, when the stop valve 22 is closed and the chemical vial 24 is attached to the nozzle 2 as shown in FIG. 6 and the flow path changeover switch 12D is moved to the front side, the high pressure gas at the rear of the pressure receiving piston 8 is discharged from the flow path 4f to the outside. To be released. As a result, the pressure receiving piston 8 is pressed by the high pressure gas at the front part and moves rearward, and a space is created in the hollow hole 2b of the nozzle 2, and the chemical liquid in the chemical liquid vial 24 is stored therein. The inside of the gas chamber 6 is at atmospheric pressure, and the injection button 14, the communication hole opening / closing rod 15, the tip-side stepped circular portion 15a, and the gasket 16 are in a state where the gas communication hole 4b is closed by the forward biasing force of the compression spring 15A. Return to. After that, if the flow path switch 12D is set to the rear position, the state shown in FIG. 3 is obtained, so that the same amount of injection can be continuously performed.

  When injecting a different amount of liquid medicine from the previous injection, the second grip 4 is held with the liquid medicine vial 24 attached when injecting a larger amount than the previous time after the state shown in FIG. In the fixed state, the first grip 3 is rotated forward to a position of a predetermined amount of the chemical solution on the scale 3d. When injection of a smaller amount than the previous time is performed, the chemical vial 24 is removed, and then the first grip 3 is rotated backward to adjust to a necessary chemical scale position. Excess chemical liquid overflows from the injection hole 2a of the nozzle 2, but may be wiped off with absorbent cotton or the like. These adjustments of the amount of the chemical solution may be performed with the stop valve 22 open or closed. Then, inhalation and injection of the chemical solution are executed according to the procedure based on the above-described FIGS.

  The present needleless syringe is not limited to the embodiment. For example, the type of high-pressure gas from the gas cylinder 21 is preferably nitrogen gas, but other types of gas can also be used. Further, instead of the gas cylinder 21, compressed air by an air compressor can be used as a power source. The nozzle 2 is detachably screwed to the first grip 3, but may be integrated with the first grip 3 by resin molding or the like. In this case, since the nozzle replacement is performed as a disposable unit for the first grip 3, it can be used as a sanitary needleless syringe.

  A high-pressure gas is used as a power source for a needleless syringe that injects and injects a fixed amount of a chemical solution from an injection hole of a nozzle.

It is the longitudinal cross-sectional view of the needleless syringe by the Example of this invention, and the block diagram of the power source. It is operation | movement explanatory drawing of the needleless syringe before use. It is operation | movement explanatory drawing of the needleless syringe at the time of chemical | medical solution inhalation. It is operation | movement explanatory drawing of the needleless syringe at the time of chemical | medical solution injection. It is operation | movement explanatory drawing of the needleless syringe which prepares the chemical | medical solution inhalation by high pressure gas after chemical | medical solution injection. It is operation | movement explanatory drawing of the needleless syringe at the time of the chemical | medical solution inhalation by a high pressure gas. It is a longitudinal section showing an example of composition of a conventional needleless syringe.

Explanation of symbols

1 Needleless syringe 2 Nozzle 2a Injection hole 2b Hollow hole 3 First grip 3a Male thread 3b Groove 3c Groove 3d Scale 3A Packing 3B Packing 4 Second grip 4A Latch 4a Female thread 4b Gas communication hole 4c Bulkhead 4d Flow path 4f Flow path 4g Cylinder 5 Chamber lid 6 Gas chamber 7 Packing 8 Pressure receiving piston 9 Piston 10 Piston rod 11 Chemical liquid pressing tool 12 Channel switching device 12A Connecting member 12B Joint 12C Joint 12D Channel switching switch 12a Channel 12b Channel 13 Joint 14 Injection Button 15 Communication hole open / close rod 15A Compression spring 15a Stepped circular portion 16 Gasket 17 Rod seal gasket 18 Support point forming member 18a Support point 19 Manual pressure control valve 20 Outlet pressure gauge 21 Gas cylinder 22 Stop valve 23 High pressure gas tube 24 Drug solution vial 25 Screw part 31 Nozzle 31a Injection hole 32 Piston 33 Compression spring 34 First (front) grip 35 Piston rod 36 Latch mechanism 37 Injection button 38 Second (rear) grip 39 Screw part 40 Screw part 41 Nut 42 Flange ring

Claims (4)

In a needleless syringe that performs hypodermic injection by pressing a chemical liquid with a piston urged by gas pressure and jetting it from an injection hole, the first grip having a nozzle for injecting the chemical liquid is screwed into the first grip A second grip in which a partition wall having a communication hole communicating in the front-rear direction is formed, a cylinder is formed on the inner side of the nozzle, and a gas chamber is formed by screwing a lid member on the other side of the partition wall; A communication hole opening / closing means for opening and closing the communication hole, a high pressure gas supply means for supplying high pressure gas to the gas chamber, and a piston connected to the high pressure gas supplied from the communication hole and sliding in the cylinder A pressure receiving piston, a first flow path communicating with the space formed by the pressure receiving piston and the first grip in the cylinder, and a communication with the gas chamber. The second flow path, the communication between the first flow path and the second flow path, the opening of the first flow path to the atmosphere and the closing of the second flow path, and the closing of the first flow path and the first flow path. A needleless syringe, comprising: a channel switching means that can switch between three states of two channels open to the atmosphere. The communication hole opening / closing means passes through an injection button comprising a fulcrum forming member provided on the outer surface of the lid member and a lever engaged with the fulcrum, and a through hole formed in the lid member, and the communication hole is formed at the front end. A communication hole opening / closing rod that forms an opening / closing part that opens and closes, and a rear end that is engaged with the lever; a spring that is wound around the communication hole opening / closing rod and applies a biasing force in a forward direction to the communication opening / closing rod; And a seal member fitted into the through hole for sealing between the communication hole opening and closing rod, and a seal member attached to the opening and closing part for sealing between the communication hole and the opening and closing part. The needleless syringe according to claim 1, characterized in that: The flow path switching means is connected to the first flow path and the second flow path, and is formed with a first outer peripheral groove connected to the first flow path and a second outer peripheral groove connected to the second flow path. A flow path connecting the first outer peripheral groove and the second outer peripheral groove is formed, and the first flow path and the second flow path are communicated with each other by fitting and sliding on the connection member, and It is composed of a flow rate change-over switch that switches between three states of opening the first flow path to the atmosphere and closing the second flow path, and closing the first flow path and opening the second flow path to the atmosphere. The needleless syringe according to claim 1. The high-pressure gas supply means includes a manual pressure control valve that controls the pressure of the high-pressure gas from the high-pressure gas source to a preset pressure corresponding to the injection site, and a stop valve that turns on and off the supply of the controlled high-pressure gas. The needleless syringe according to claim 1, further comprising a joint provided on the lid member.

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