WO2012092715A1

WO2012092715A1 - Magnetic damping pneumatic impact type needless injector

Info

Publication number: WO2012092715A1
Application number: PCT/CN2011/070075
Authority: WO
Inventors: 钟康明; 张文芳; 贾军鹏
Original assignee: 无锡圆容生物医药股份有限公司
Priority date: 2011-01-07
Filing date: 2011-01-07
Publication date: 2012-07-12

Abstract

A magnetic damping pneumatic impact type needleless injector comprises a reversing valve (1), a switch (2), a pneumatic pipeline accessory (3), a mechanical part and an injection part. The mechanical part comprises a rear end cover (4), a cylinder barrel (5), an impact plunger (7), a return spring (8), an energy storage plunger (6) and a front end cover (10). The energy storage plunger (6) is fixedly connected in the cylinder barrel (5), and the impact plunger (7) is placed in the cylinder barrel (5) in a manner of sliding. A permanent magnet (13) is fixed in an inner hole of the impact plunger (7) and the impact plunger (7) attracts the energy storage plunger (6) magnetically. The return spring (8) is connected with the impact plunger (7) and the front end cover (10). The front end cover (10) is fixedly connected on the right end surface of the cylinder barrel (5) and the rear end cover (4) is fixedly connected on the left end surface of the cylinder barrel (5). The injector is adaptable to high frequency injections and can reduce impact noises.

Description

Magnetic damping pneumatic impact needleless syringe

FIELD OF THE INVENTION The present invention relates to the field of a pneumatic needle-free injector for intradermal, subcutaneous or intramuscular injection of a human or animal. BACKGROUND OF THE INVENTION Needle-free injection refers to an instantaneous high pressure generated by a mechanical device (such as a spring or a high-pressure gas) forcing a medicament to be extruded from a fine air to form a high-pressure jet. The jet velocity is extremely high, typically 120-300 m/s, allowing the agent to penetrate quickly. Human or animal skin, the best part of the drug absorption. Compared with traditional subcutaneous injection, needle-free injection has many advantages, among which: the needle-free syringe has little stimulation to the nerve endings when injecting the medicament, and has no obvious pain, which can reduce the pain and fear caused by the use of a hypodermic needle. It eliminates the local skin damage caused by traditional injection methods, the risk of bleeding and infection, and reduces the environmental pollution caused by the treatment of dirty needles. Based on the above advantages, needle-free injectors have broad market prospects. With the development of science and technology and the promotion of clinical needs since the 1980s, the research on needle-free injectors has shown a booming trend. The needle-free injection techniques that are currently known can be classified into three categories according to their power sources: compressed gas, fuel, and hard spring. A total of more than 20 related invention patents have been published or authorized at home and abroad. Similar to rocket technology, the method of detonating fuel to generate shock waves can provide sufficient boosting force, but its potential dangers and instability are also worrying; Equidyne Systems, Inc., a subsidiary of Equidyne Corporation, USA A spring-type needleless syringe has been successfully developed for 8 years. It has been put into the market in batches in July 2000. The syringe consists of a fuselage, a resetter, a disposable ampoule, and a adapter. In use, the needle-free injector is reset to a full pressure state by a resetter, and the disposable ampoule is sleeved to the front end of the needle-free injector for injection, which is effective in some aspects, but is greatly affected in practical applications. The limitation is that since the impact device is separated from the spring return device, it is not only extremely inconvenient to operate, but also extremely unsuitable for occasions where the frequency of injection is relatively high. In addition, the trigger mechanism of the existing mechanical impact device is an exposed lever mechanism, which is extremely likely to cause false triggering and cause accidental injury. In order to avoid accidental triggering of the existing mechanical impact device, an interlocking safety mechanism is specially provided. When the medical staff is performing the injection, the safety mechanism must be pushed and pulled by one hand, and the lever type pawl switch is pressed by the other hand to complete the injection. Since the injection head itself is small in volume, it is extremely inconvenient to use both hands to cooperate at the same time, which greatly restricts the promotion and application of the needle-free injector in the medical industry. In addition, the conventional compressed gas method requires a high-pressure gas cylinder and a corresponding air compression device, which is bulky, expensive, time consuming, and extremely inconvenient to use. After repeated research, we used a power-controlled two-position three-way reversing valve to control the airflow in and out of the silent air pressure system as a compressed air source, successfully designed a high efficiency, low labor intensity of medical staff, The utility model has the advantages of convenient operation, slight noise, and a pneumatic needleless syringe with adjustable injection force within a certain range, which is convenient for the use of clinical medical personnel and has a very good market prospect.

The needle-free injector of the present invention has high efficiency, can reduce the labor intensity of the medical staff, and can adjust the supply pressure or the area of the impact piston so that the injection force can be adjusted within a certain range. In addition, due to the use of electrical switch control, the operation is very convenient, and the spring has a damping buffer, so the noise is slight. SUMMARY OF THE INVENTION It is an object of the present invention to provide a pneumatically driven needleless injection impact device that is easy to operate, can accommodate high frequency injections, and reduces impact noise.

The present invention is achieved by the following technical solutions: A magnetically damped pneumatic impact type needleless injector comprising a reversing valve, a switch, a pneumatic line attachment, a mechanical part and an injection part, the mechanical part comprising a cylinder barrel, an impact piston a return spring, an accumulator piston and a front end cover, the accumulator piston is fixedly connected in the cylinder tube, the accumulating piston is provided with a pneumatic through hole, the impact piston is arranged in a sliding manner in the cylinder tube, and a permanent magnet is arranged in the impact piston. The impact piston and the accumulator piston are magnetically attracted, the return spring is connected with the impact piston and the front end cover, the front end cover is threadedly connected to the right end of the cylinder barrel, and the rear end cover is screwed to the left end of the cylinder barrel; the reversing valve is preferably two-position three-way exchange The valve can also be a two-position four-way or two-position five-way reversing valve, the injection part is composed of an injection piston and an injection syringe, and the injection syringe is fixed with a thread or a buckle to the front end cover; End cap threaded connection. The accumulator piston is fixedly connected in the cylinder tube, and a permanent magnet is placed in the impact piston, and the impact piston and the accumulator piston are magnetically attracted to form a magnetic damping device. In order to prevent the cylinder from affecting the magnetic damping device, the cylinder is made of an antimagnetic metal material, preferably copper, aluminum alloy or stainless steel. The accumulator piston is fixedly connected in the cylinder tube to connect the screw connection or the pin. The accumulator piston is provided with at least one pneumatic through hole, and the accumulator piston and the cylinder tube form an energy storage cavity.

When the impact piston is in the non-working position, an idle stroke of 4-10 mm is provided between the right end surface and the left end surface of the injection piston, so that the impact piston has a sufficient speed to impact the injection piston, and the front end of the syringe has at least one micro hole, the micro hole The diameter is 30-100um, the injection piston is high-speed extrusion liquid, so that the liquid can pass through the micropores through the skin of human or animal, and can be used for intradermal injection, subcutaneous injection or intramuscular injection to deliver a certain dose to the animal or human body. Liquid or powder. The invention adds an energy storage cavity and a magnetic damping device, so that the acceleration of the impact piston is high, the impact force is large, and the injection pressure can be adjusted within a certain range by adjusting the permanent magnets with different supply pressure and magnetic force. The magnetically damped pneumatic impact needleless injector is small in size, simple in structure and convenient to use. DRAWINGS

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic view showing the structure of an initial state of a magnetically damped pneumatic impact type needleless injector of the present invention.

Fig. 2 is a structural schematic view showing the state in which the magnetically damped pneumatic impact type needleless injector of the present invention is started to be injected.

Fig. 3 is a structural schematic view showing the state of completion of injection of the magnetically damped pneumatic impact type needleless syringe of the present invention. In the figure, 1. Reversing valve, 2. Switch, 3. Pneumatic piping attachment, 4. Rear end cover, 5. Cylinder, 6. Accumulator piston, 7. Impact piston, 8. Reset spring, 9. Injection Piston, 10. Front end cover, 11. Injection syringe, 12. Vent, 13. Permanent magnet, 14. Accumulator chamber, 15. Pneumatic through hole. Specific embodiment:

As shown in Fig. 1, the reversing valve 1, the switch 2, the pneumatic attachment 3 are sequentially connected, the pneumatic attachment 3 is screwed to the rear end cover 4, the rear end cover 4 is fixedly attached to the left end of the cylinder barrel 5, and the accumulator piston 6 is fixedly connected thereto. In the cylinder 5, an accumulator chamber 14 is formed with the cylinder 5, and the accumulator piston 6 is provided with a pneumatic through hole 15, and the impact piston is slidably disposed in the cylinder 5, and the left end of the impact piston is provided with a permanent magnet 13, The permanent magnet 13 is magnetically attracted to the plane of the accumulator piston 6, so that the impact piston 7 seals the right end of the pneumatic through hole 15. The reset spring 8 is connected to the impact piston Ί and the front end cover 10, and the cylinder 5 is provided with a vent hole 12 at one end of the near return spring 8, and the vent hole 12 is open to the atmosphere.

The switch 2 is in the off state, the reversing valve 1 is in the off state, and the compressed air delivered by the compressed air source cannot enter the cylinder 5 through the pneumatic pipe attachment 3, and the injection needle 11 and the front end cover 10 are threaded. connection. The injection piston 9 is placed in the return spring 8 of the cylinder 5, and one end projects into the injection needle barrel 11. As shown in Fig. 2, the medicament is pre-injected into the syringe 11, and when the switch 2 is initially closed, the diverter valve 1 is turned on, and the compressed air is supplied from the compressed air source through the pneumatic line. At the time of the attachment 3, entering the energy storage chamber 14, the pressure is low due to the gas flow, and the magnetic force of the permanent magnet 13 and the resistance of the return spring 8 are insufficient, and the impact piston 7 cannot move; when the air pressure in the energy storage chamber 14 is impacted When the thrust of the piston 7 is greater than the magnetic force of the permanent magnet 13 in the impact piston 7, the impact piston 7 starts to move, and since the suction force of the permanent magnet 13 is gradually weakened, the impact piston 7 will move toward the injection needle 11 with a high acceleration, over An empty stroke (acceleration stroke) between the right end surface and the left end surface of the injection piston 9 of the injection assembly impacts the left end surface of the injection piston 9 of the injection assembly at a high speed, causing it to move to the right at a high speed, by squeezing the injection needle The liquid medicine in the cylinder 11 passes through the micropores at the front end of the injection syringe 11, and is ejected at a high speed jet. When the injection process is finished, the impact piston 7 reaches the map. 3 position shown.

After the injection process is finished, the switch 2 is opened, the electromagnet of the reversing valve 1 is de-energized, the reversing valve 1 is switched to the off state shown in Fig. 1, and the impact piston 7 is reset to the leftmost position by the return spring 8. , to prepare for the next injection. It will be appreciated that those skilled in the art will be able to devise various modifications and various embodiments of the mechanical components of the present invention. For example, removing the rear end cover allows the cylinder to become a unitary structure for processing; designing the magnetic damper in different forms; resetting by gravity without using a spring return; and designing the venting holes in other positions. Therefore, it is to be understood that the scope of the present invention should cover all such embodiments based on the modifications.

Claims

The invention provides a magnetically damped pneumatic impact needleless injector comprising a reversing valve, a switch, a pneumatic line attachment, a mechanical part and an injection part, the mechanical part comprising a rear end cover, a cylinder barrel, an impact piston, a return spring The energy storage piston and the front end cover are characterized in that: the energy storage piston is fixed in the cylinder, the impact piston is arranged in the cylinder in a sliding manner, and the permanent magnet is fixed in the inner hole of the impact piston, and the impact piston and the energy storage piston plane are fixed. Magnetically attracted, the return spring is connected to the impact piston and the front end cover, the front end cover is fixed to the right end surface of the cylinder barrel, and the rear end cover is fixed to the left end surface of the cylinder barrel. The magnetically damped pneumatic impact needleless injector according to claim 1, wherein: when the impact piston is in the non-working position, an idle stroke is set between the right end surface and the left end surface of the injection piston, and the distance is 4-10mm The magnetically damped pneumatic impact type needleless injector according to claim 1, wherein: the right end surface of the cylinder barrel is provided with a vent hole. The magnetically damped pneumatic impact needleless injector according to claim 1, wherein the accumulator piston is provided with a pneumatic through hole.

The magnetically damped pneumatic impact needleless injector according to claim 1, wherein the cylinder is made of an antimagnetic metal material and may be copper, aluminum alloy or stainless steel. The magnetically damped pneumatic impact needle-free injector according to claim 1, wherein: the injection portion is composed of an injection piston and an injection syringe with a micro-hole, wherein the injection cylinder is threaded or bayonet-mounted The front end cover is connected. The injection syringe according to claim 6, wherein: the front end of the syringe has at least one micro hole, and the diameter of the micro hole is 30-100