CN112006841B

CN112006841B - Self-draining type heavy water injection device for ophthalmic surgery

Info

Publication number: CN112006841B
Application number: CN202010931175.XA
Authority: CN
Inventors: 谢琦莲; 裴克; 朱晶晶; 郭佳音
Original assignee: First Affiliated Hospital of Henan University of Science and Technology
Current assignee: First Affiliated Hospital of Henan University of Science and Technology
Priority date: 2020-09-07
Filing date: 2020-09-07
Publication date: 2022-04-08
Anticipated expiration: 2040-09-07
Also published as: CN112006841A

Abstract

The invention relates to the field of ophthalmic surgery equipment, in particular to a self-discharging type heavy water injection device for ophthalmic surgery. The double-cavity injection syringe comprises a double-cavity needle head, a double-cavity injection tube and a double-cavity injection tube, wherein the double-cavity needle head is provided with an injection channel for injecting heavy water into eyeballs and a discharge channel for discharging liquid in the eyeballs; the injection cavity is internally provided with an injection piston head in a sliding manner, the injection piston head is connected with an injection piston rod, the discharge cavity is internally provided with a discharge piston head in a sliding manner, and the discharge piston head is connected with a discharge piston rod, so that when the injection piston rod is injected into the double-cavity injection tube to inject heavy water in the injection cavity into an eyeball, the discharge piston rod is pulled outwards to extract the liquid in the eyeball, which is equal to the injected heavy water, into the discharge cavity. The invention can synchronously and equivalently extract the liquid in the eyeball in the process of injecting the heavy water, thereby maintaining the stability of intraocular pressure.

Description

Self-draining type heavy water injection device for ophthalmic surgery

Technical Field

The invention relates to the field of ophthalmic surgery equipment, in particular to a self-discharging type heavy water injection device for ophthalmic surgery.

Background

The heavy water in ophthalmology is a purified perfluorocarbon liquid, has specific gravity higher than that of water, is transparent, has certain surface tension, and has no biological toxicity in short-time application. Based on the characteristics, the proper use of heavy water in the operation can help the operator to smoothly release the subretinal fluid, smoothly separate from the retina, press for hemostasis and realize the intravitreal floating of the crystal nucleus and the foreign body in the ball to be beneficial to taking out. Compared with sharp knife scissors under a microscope, heavy water is known as a 'soft apparatus' in ophthalmic surgery due to the facts that heavy water is more talent and more artistic, colorless and shapeless.

The heavy water is usually injected into the eyeball by a conventional syringe, but because the intraocular volume is fixed and has a certain amount of liquid, in order to maintain the intraocular pressure stable, the conventional injection method is to inject a certain amount of heavy water into the eyeball, pull out the syringe, and then insert another syringe into the eyeball to suck up an equal amount of liquid from the eyeball. The operation not only prolongs the operation time, but also easily enlarges the puncture hole by repeatedly plugging and unplugging the syringe needle in the eyeball, thereby causing unnecessary injury. In response to this problem, a double lumen needle as disclosed in CN204600878U has been proposed in the prior art, which has an injection channel for heavy water injection into the eyeball and a discharge channel for the discharge of the liquid from the eyeball, the injection channel still being connected to a conventional syringe, the discharge channel being additionally connected to a liquid storage bag. Although the double-cavity needle head can enable liquid in the eyeball to be automatically discharged outside through the discharge channel in the heavy water refraction process, the damage to the eyeball caused by repeatedly inserting and pulling the needle head is avoided. However, the driving force for discharging the liquid inside the eyeball is from the squeezing effect of the injected heavy water on the inner cavity of the eyeball, the liquid inside the eyeball can be discharged through the discharge channel only after the heavy water is injected and the intraocular pressure is increased to a certain degree, and the intraocular pressure is maintained to a larger degree all the time during the discharge process, so that the intraocular bleeding is still easy to cause, and especially for patients suffering from basic diseases (such as diabetes) or high myopia, the operation still has a larger risk.

Disclosure of Invention

The invention aims to provide a self-discharging type heavy water injection device for an ophthalmic surgery, which can synchronously and equivalently extract liquid in eyeballs in the heavy water injection process so as to maintain the stability of intraocular pressure.

In order to solve the technical problems, the invention adopts the technical scheme that: a self-discharging type heavy water injection device for ophthalmic surgery comprises a double-cavity needle head, a double-cavity injection tube and a self-discharging device, wherein the double-cavity needle head is provided with an injection channel for injecting heavy water into eyeballs and a discharge channel for discharging liquid in the eyeballs; the injection cavity is internally provided with an injection piston head in a sliding manner, the injection piston head is connected with an injection piston rod, the discharge cavity is internally provided with a discharge piston head in a sliding manner, and the discharge piston head is connected with a discharge piston rod, so that when the injection piston rod is injected into the double-cavity injection tube to inject heavy water in the injection cavity into an eyeball, the discharge piston rod is pulled outwards to extract the liquid in the eyeball, which is equal to the injected heavy water, into the discharge cavity, and the intraocular pressure is maintained to be stable.

Preferably, a reverse synchronous driving mechanism is arranged between the injection piston rod and the discharge piston rod, so that in the process of pushing the injection piston rod inwards, the discharge piston rod can be controlled by the reverse synchronous driving mechanism to be pulled outwards synchronously, and the liquid in the eyeball is extracted into the discharge cavity synchronously;

the reverse synchronous driving mechanism is a first gear, the first gear is rotatably arranged at the tail end of the double-cavity injection cylinder, one side of the first gear is meshed and matched with a first rack arranged on the injection piston rod, and the other side of the first gear is meshed and matched with a second rack arranged on the discharge piston rod.

Preferably, the end cap is arranged at the tail end of the double-cavity injection cylinder, the end cap is provided with a cavity, the first gear is rotatably arranged in the middle of the cavity of the end cap, a first guide hole for positioning and penetrating the injection piston rod and a second guide hole for positioning and penetrating the discharge piston rod are respectively arranged on the two sides of the first gear on the end cap, the tail end of the injection piston rod penetrates through the first guide hole and then is fixedly connected with the push-pull handle, and the tail end of the discharge piston rod penetrates through the second guide hole and then is arranged in a through hole formed in the push-pull handle in a penetrating manner.

Preferably, the double-cavity injection tube is also provided with a semi-automatic linkage mechanism for linking the movement of the injection piston rod and the discharge piston rod, the semi-automatic linkage mechanism can be used for controlling the synchronous outward pulling of the discharge piston rod in the process of pushing the injection piston rod inwards to inject heavy water into the eyeball, and the semi-automatic linkage mechanism is also used for controlling the synchronous outward pulling of the discharge piston rod at the tail end of the injection piston rod for the synchronous extraction of the heavy water by the discharge cavity;

the semi-automatic linkage mechanism comprises a third rack arranged on the injection piston rod, a fourth rack arranged on the discharge piston rod, a first gear box fixed at the tail end of the double-cavity injection tube and a first gear rack arranged between the third rack and the fourth rack and capable of being distributed in the first gear box in a sliding mode along the radial direction of the double-cavity injection tube; a first reverse driving component and a first reverse driving component are sequentially arranged on the first gear carrier along the sliding direction of the first gear carrier, the first reverse driving component is a third gear which is rotatably arranged on the first gear carrier, the first reverse driving component is a fourth gear and a fifth gear which are rotatably arranged on the first gear carrier and are mutually meshed, the fourth gear is distributed on one side close to the third rack, the fifth gear is distributed on one side close to the fourth rack, and the central axis directions of the third gear, the fourth gear and the fifth gear are all distributed in parallel to the sliding direction of the first gear carrier;

an opening for one end of the first gear rack to extend out is formed in the first gear box, the corresponding end of the first gear rack can extend out of the opening and form a pressing part, and after the first gear rack is pressed into the first gear box through the pressing part, the fourth gear is meshed with the third rack and the fifth gear is meshed with the fourth rack; the other end of the first gear box in the sliding direction of the first gear rack is provided with a first spring for pushing the pressing part of the first gear rack out of the opening, so that two sides of the third gear are respectively meshed with the third rack and the fourth rack after the pressing part of the first gear rack is pushed out of the opening through the first spring.

Preferably, the first gear rack is in an inverted chevron shape and comprises a first support plate and three first vertical plates fixed at the lower edge of the first support plate at intervals, a sliding groove for the three first vertical plates to be in sliding fit is formed in the bottom of the first gear box, and shaft holes for the third gear, the fourth gear and the fifth gear to be in rotating fit are correspondingly formed in the three first vertical plates; the splenium is fixed for pressing the press handle for being located the columniform on the first riser of one of them one end of first backup pad, and the opening shape on the first gear box is corresponding with pressing the press handle shape, and first spring setting is located between the first riser of the other end of first backup pad and the first gear box lateral wall.

Preferably, the double-cavity injection tube is also provided with an automatic linkage mechanism for linking the movement of the injection piston rod and the discharge piston rod, and the automatic linkage mechanism is used for automatically controlling the synchronous outward pulling of the discharge piston rod in the process of pushing the injection piston rod inwards to inject heavy water into the eyeball or the synchronous outward pulling of the discharge piston rod at the tail end of the injection piston rod for extracting the heavy water;

the automatic linkage mechanism comprises a fifth rack arranged on the injection piston rod, a sixth rack and a seventh rack which are arranged on the discharge piston rod at intervals, a second gear box fixed at the tail end of the double-cavity injection tube and a second gear frame which is distributed in the second gear box in a sliding manner along the radial direction of the double-cavity injection tube; a second reverse driving component and a second same-direction driving component are arranged on the second gear frame at intervals along the sliding direction of the second gear frame, the second reverse driving component is a sixth gear rotationally arranged on the second gear frame, the second same-direction driving component is a seventh gear and an eighth gear which are rotationally arranged on the second gear frame and are mutually meshed, the eighth gear is distributed on one side close to the fifth rack, the seventh gear is distributed on one side close to the seventh rack, and the central axis directions of the sixth gear, the seventh gear and the eighth gear are all distributed in parallel to the sliding direction of the second gear frame;

the eighth gear is meshed with the fifth rack, a second spring is arranged between one end of the second gear frame in the self sliding direction and the corresponding side wall of the second gear box and used for maintaining that two sides of the sixth gear are respectively meshed with the fifth rack and the sixth rack, the eighth gear is meshed with the fifth rack, and the seventh gear is separated from the seventh rack; and a guide convex strip is arranged on the injection piston rod along the length direction of the injection piston rod, the end part of the guide convex strip corresponding to the second gear frame is in a wedge shape and can be in contact fit with the end part of the second gear frame far away from the second spring, so that the second gear frame is automatically controlled by the guide convex strip to slide towards the direction of the second spring in the process of pulling the injection piston rod outwards, and the sixth gear is automatically controlled to be separated from the sixth rack and the seventh gear is automatically controlled to be meshed with the seventh rack.

Preferably, the injection piston rod is provided with a connecting rib plate for fixing the guide convex strip, and the connecting rib plate is L-shaped.

Preferably, a double-cavity catheter is connected between the double-cavity syringe and the double-cavity needle.

Advantageous effects

The invention is provided with a double-cavity injection tube besides a double-cavity needle, and an injection piston rod and a discharge piston rod are respectively arranged in an injection cavity and a discharge cavity in the double-cavity injection tube. After the double-cavity needle is inserted into the eyeball of a patient, in the process of injecting heavy water into the eyeball by the inner injection piston rod, the discharge piston rod can be simultaneously pulled outwards at a constant speed to suck the liquid in the eyeball, which is equal to the injected heavy water, into the discharge cavity, so that the intraocular pressure is maintained to be stable.

In the preferred embodiment of the invention, a reverse synchronous driving mechanism is arranged between the injection piston rod and the discharge piston rod, and an operator can push the injection piston rod in the push-pull handle downwards to pull the discharge piston rod outwards at a constant speed synchronously, so that the injection speed of the heavy water and the discharge speed of the liquid in the eyeball are automatically matched, the operation and the use of medical personnel are facilitated, and the stability of intraocular pressure in the heavy water injection process is further maintained.

In other embodiments of the present invention, a semi-automatic linkage mechanism or a full-automatic linkage mechanism is further disposed between the injection piston rod and the discharge piston rod, so as to realize synchronous reverse motion of the injection piston rod and the discharge piston rod during the injection process; on the other hand, before injection, the injection piston rod is pulled outwards to extract the tail section of heavy water from the injection cavity through the injection passage of the double-cavity needle, so that the discharge piston rod can also be pulled outwards synchronously to extract a certain amount of heavy water from the discharge cavity through the discharge passage of the double-cavity needle. Therefore, when heavy water is injected into the eyeball, the heavy water in the discharging cavity can be more accurately discharged by the low compression rate of the heavy water, the same amount of the heavy water as the heavy water is injected into the eyeball, the discharging channel of the double-cavity needle head or the air in the double-cavity catheter for connecting the double-cavity injection tube and the double-cavity needle head is prevented from being pumped into the discharging cavity, the amount of the liquid in the eyeball which is pumped out due to the high compression rate of the air is slightly lower than the amount of the heavy water which is injected, and the intraocular pressure is further accurately maintained.

Drawings

FIG. 1 is a schematic structural diagram of embodiment 1 of the present invention in an initial state;

FIG. 2 is a schematic structural view of an injection chamber of embodiment 1 of the present invention in a state where heavy water is sucked and injection of heavy water is ready;

FIG. 3 is a schematic structural diagram of embodiment 2 of the present invention in an initial state;

FIG. 4 is a sectional view taken along line A-A of FIG. 3;

FIG. 5 is a schematic structural view showing a state where the injection chamber sucks heavy water and the discharge chamber does not suck heavy water in embodiment 2 of the present invention;

FIG. 6 is a sectional view taken along line B-B of FIG. 5;

FIG. 7 is a schematic structural view showing a state where the injection chamber and the discharge chamber of embodiment 2 of the present invention both suck in heavy water and are ready for heavy water injection;

FIG. 8 is a schematic structural diagram of embodiment 3 of the present invention in an initial state;

FIG. 9 is a cross-sectional view taken along line C-C of FIG. 8;

FIG. 10 is a schematic structural view showing a state where the injection chamber sucks in heavy water and the discharge chamber does not suck in heavy water in embodiment 3 of the present invention;

FIG. 11 is a sectional view taken along line D-D of FIG. 10;

FIG. 12 is a sectional view taken along line E-E in FIG. 11;

FIG. 13 is a schematic structural view showing a state where the injection chamber and the discharge chamber of embodiment 3 of the present invention both suck in heavy water and are ready for heavy water injection;

FIG. 14 is a schematic diagram of a dual lumen needle of the present invention;

the labels in the figure are: 1. a push-pull handle, 2, an injection piston rod, 3, a first rack, 4, a dual-cavity syringe, 5, an injection cavity, 6, an injection piston head, 7, a dual-cavity needle, 701, an injection channel, 702, an exhaust port, 703, an exhaust channel, 704, an injection port, 8, a partition plate, 9, an exhaust cavity, 10, an exhaust piston head, 11, an end cap, 12, a wheel shaft, 13, a first gear, 14, an exhaust piston rod, 15, a second rack, 16, heavy water, 17, a third rack, 18, a first gear box, 19, a first gear box, 1901, a first sliding block, 1902, a pressing part, 1903, a first vertical plate, 1904, a first supporting plate, 20, a fourth rack, 21, a first spring, 22, a third gear, 23, a fourth gear, 24, a fifth gear, 25, a dual-cavity catheter, 26, a limiting block, 27, a fifth rack, 28, a second gear box, 29, a second gear box, 2901, a second sliding block, 2902. the second vertical plate 2903, the second support plate 30, the seventh rack 31, the guide convex strip 32, the connecting rib plate 33, the eighth gear 34, the sixth rack 35, the second spring 36, the sixth gear 37 and the seventh gear.

Detailed Description

The self-discharging type heavy water injection device for ophthalmic surgery is used for synchronously and equivalently pumping liquid in eyeballs in the process of injecting heavy water 16 into the eyeballs, so that compared with the prior art, the stability of the intraocular pressure can be greatly improved. In order to achieve the technical effect, the invention is provided with a double-cavity needle 7 and a double-cavity injection cylinder 4 connected with the double-cavity needle 7.

Double lumen needle 7 is shown in FIG. 14 as including an injection channel 701 and an exhaust channel 703. Since the heavy water 16 has a high density and is located at the bottom of the eyeball after the injection, in order to prevent the heavy water 16 injected into the eyeball from being immediately drawn out, an injection port 704 is provided at the bottom of the injection passage 701, and a discharge port 702 communicating with the discharge passage 703 is provided above the injection port 704.

The double-cavity injection tube 4 comprises a tube body and a partition plate 8 arranged in the tube body, wherein the partition plate 8 divides the inner cavity of the tube body into an injection cavity 5 and a discharge cavity 9 which are mutually isolated, as shown in figures 1, 3 or 8. The injection cavity 5 is communicated with an injection channel 701 of the double-cavity needle 7, an injection piston head 6 capable of longitudinally sliding is arranged in the injection cavity 5, the injection piston head 6 is connected with an injection piston rod 2, and the injection piston rod 2 penetrates out of the tail part of the injection cavity 5; the discharge cavity 9 is communicated with the discharge channel 703 of the double-cavity needle 7, a discharge piston head 10 which can slide longitudinally is also arranged in the discharge cavity 9, a discharge piston rod 14 is connected to the discharge piston head 10, and the discharge piston rod 14 penetrates out of the tail part of the discharge cavity 9. After the double-cavity needle 7 is inserted into the heavy water bottle, the injection piston rod 2 can be pulled outwards to suck heavy water 16 into the injection cavity 5; after the double-cavity needle 7 is inserted into the eyeball, the heavy water 16 in the injection cavity 5 can be injected into the eyeball by pushing the injection piston rod 2 inwards, and the discharge piston rod 14 can be pulled outwards at a constant speed synchronously, so that the liquid in the eyeball is pumped into the discharge cavity 9 through the discharge channel 703, and the technical effect of greatly improving the stability of the intraocular pressure compared with the prior art is achieved.

The invention is further illustrated in detail in the following 3 examples:

example 1

As shown in fig. 1, a reverse synchronous drive mechanism is provided between the injection piston rod 2 and the ejection piston rod 14 in this embodiment. The reverse drive mechanism is used to drive the injection piston rod 2 and the discharge piston rod 14 in a synchronized reverse movement in the longitudinal direction along the double-chamber syringe 4. Therefore, in the process of injecting the injection piston rod 2 internally to inject the heavy water 16 in the injection cavity 5 into the eyeball, the reverse synchronous driving mechanism controls the discharge piston rod 14 to be synchronously pulled outwards so as to synchronously extract the liquid in the eyeball into the discharge cavity 9.

The reverse synchronous driving mechanism is a first gear 13 which is rotatably arranged in an end cover 11 fixed at the tail end position of the double-cavity injection cylinder 4. The end cap 11 has a cavity, the wall of the end cap 11 is provided with a plurality of air holes respectively communicated with the injection cavity 5 or the discharge cavity 9, the middle part of the cavity is provided with a U-shaped gear seat right above the clapboard 8, both ends of the first gear 13 in the axial direction are provided with wheel shafts 12, and the wheel shafts 12 are rotatably installed in corresponding shaft holes arranged on the gear seat. The left side of the first gear wheel 13 is in meshing engagement with a first toothed rack 3 provided on the injection piston rod 2, and the right side of the first gear wheel 13 is in meshing engagement with a second toothed rack 15 provided on the discharge piston rod 14. A first guide hole for positioning and penetrating the injection piston rod 2 and a second guide hole for positioning and penetrating the discharge piston rod 14 are respectively arranged on the end cover 11 and positioned on two sides of the first gear 13, the tail end of the injection piston rod 2 penetrates through the first guide hole and then is fixedly connected with the push-pull handle 1, and the tail end of the discharge piston rod 14 penetrates through the second guide hole and then is arranged in a through hole arranged on the push-pull handle 1.

In the initial state of this embodiment as shown in fig. 1, after the double lumen needle 7 is inserted into the heavy water bottle, the push-pull handle 1 is pulled outward to move the injection piston head 6 upward to draw the heavy water 16 into the injection lumen 5, and simultaneously the exhaust piston head 10 is moved downward to exhaust the air in the exhaust lumen 9 until the exhaust piston head 10 is pushed to the bottom of the exhaust lumen 9 to reach the state shown in fig. 2. The double lumen needle 7 is now inserted into the eye and the handle 1 is pushed in, causing the injection piston head 6 to move down to inject the heavy water 16 in the injection lumen 5 into the eye, while the discharge piston head 10 moves up to withdraw the liquid in the eye.

Example 2

As shown in FIG. 3, the double-lumen syringe 4 in this embodiment is not directly connected to the double-lumen needle 7, but is connected to the double-lumen catheter 25 made of a flexible material. Through this two-chamber pipe 25, can make the operator puncture two-chamber syringe needle 7 to the eyeball after, remote control two-chamber syringe 4 carries out the heavy water 16 injection, avoids directly leading under the condition with operation two-chamber syringe 4 to lead to two-chamber syringe needle 7 synchronous vibrations, skew or other emergency under two-chamber syringe needle 7 to tear, wrench movement or other damage that the eyeball puncture hole caused.

The dual chamber syringe 4 in this embodiment also has a semi-automatic linkage for linking the movement of the injection piston rod 2 and the discharge piston rod 14. The semi-automatic linkage mechanism has the functions that: on one hand, the function of the reverse phase synchronous driving mechanism is the same as that of the reverse phase synchronous driving mechanism in the embodiment 1, after the double-cavity needle 7 is inserted into the eyeball, the discharging piston rod 14 is controlled to push the injection piston rod 2 inwards to be synchronously pulled outwards in the process of injecting heavy water 16 into the eyeball, and the liquid in the eyeball is discharged synchronously with the injection; on the other hand, because the double lumen catheter 25 has a longer length and contains more air therein, during the process of injecting the heavy water 16, i.e. pushing the injection piston rod 2 inward and pulling the discharge piston rod 14 outward, the air in the corresponding channels of the double lumen catheter 25 and the double lumen needle 7 will be drawn into the discharge chamber 9 by the outward pulling movement of the discharge piston head 10. Because air has a larger compression ratio, the air is directly expanded in the outward pulling movement process (especially in the early stage) of the piston head 10, instead of directly extracting liquid from the eyeball, and further the phenomenon that the injected heavy water 16 is asynchronous with the extracted liquid in the eyeball and is unequal is caused. Therefore, the semi-automatic linkage mechanism in this embodiment can also control the discharging piston rod 14 to pull out the injection piston rod 2 to pull out the synchronous pulling-out of the end of the heavy water 16 after the double-cavity needle 7 is inserted into the heavy water bottle, so that the discharging cavity 9 can synchronously pull out a certain amount of heavy water 16, and the heavy water 16 fills the corresponding channels of the double-cavity needle 7 and the double-cavity catheter 25, so as to eliminate the delay caused by the air expansion in the injection cavity 5, namely the non-equivalent effect of extracting the liquid in the eyeball, by the low compression ratio of the filled heavy water 16.

Referring to fig. 3 and 4, the semi-automatic linkage mechanism in this embodiment includes a third rack 17 disposed on the injection piston rod 2, a fourth rack 20 disposed on the discharge piston rod 14, a first gear box 18 fixed to the rear end of the dual chamber syringe 4, and a first gear rack 19 disposed in the first gear box 18. The first carrier 19 is slidably disposed in the first gear case 18 at a position between the third rack 17 and the fourth rack 20, and the sliding direction of the first carrier 19 is parallel to the upper edge of the partition 8. The first carrier 19 is provided with a first reverse driving component and a first forward driving component in sequence from back to front along the sliding direction of the first carrier 19, which is shown in fig. 1. The first reverse driving component is a third gear 22 rotatably disposed on the first gear rack 19, the first reverse driving component is a fourth gear 23 and a fifth gear 24 rotatably disposed on the first gear rack 19 and engaged with each other, the fourth gear 23 is disposed on a side close to the third rack 17, the fifth gear 24 is disposed on a side close to the fourth rack 20, and central axes of the third gear 22, the fourth gear 23 and the fifth gear 24 are all disposed in parallel to a sliding direction of the first gear rack 19. Thus, the first counter drive assembly and the second counter drive assembly are engaged with the third rack 17 and the fourth rack 20 respectively by controlling the sliding of the first gear rack 19 along the double-chamber syringe 4 in the transverse direction, so as to realize the synchronous movement of the injection piston rod 2 and the discharge piston rod 14 in the same direction or in opposite directions.

The first carrier 19 is formed in an inverted chevron shape and includes a first support plate 1904 and three first vertical plates 1903 fixed to the lower edge of the first support plate 1904 at intervals. The first supporting plates 1904 are horizontally distributed, and the three first standing plates 1903 are parallel to each other and vertically distributed. Two first sliding blocks 1901 are disposed at intervals at the lower ends of the three first vertical plates 1903, and a sliding groove for slidably fitting the first sliding blocks 1901 is correspondingly disposed at the bottom of the first gear box 18, so that the first gear rack 19 can slide along the sliding groove as a whole. Three first vertical plates 1903 are correspondingly provided with shaft holes for the rotation of the third gear 22, the fourth gear 23 and the fifth gear 24.

In fig. 3, an opening is provided at the front end of the first gear case 18, a cylindrical pressing portion 1902 having a shape corresponding to the opening is provided on the first upright plate 1903 located at the front end, and a first spring 21 is provided between the first upright plate 1903 located at the rear end and the corresponding side wall of the first gear case 18. As shown in fig. 4, in the initial state of the present embodiment, the first spring 21 pushes the first carrier 19 to move forward as a whole, and the stopper 26 on the pressing portion 1902 is pressed against the inner wall of the first gear case 18. Both sides of the third gear 22 at this time are engaged with the third rack 17 and the fourth rack 20, respectively. After the pressing portion 1902 is pressed into the opening by an external force, the first gear rack 19 compresses the first spring 21 and moves backward as a whole, and after the outer end of the pressing portion 1902 is flush with the opening, the state shown in fig. 6 is reached, such that the fourth gear 23 is engaged with the third rack 17 and the fifth gear 24 is engaged with the fourth rack 20. After the external force disappears, the first carrier 19 moves forward again by the elastic potential energy accumulated in the first spring 21, and both sides of the third gear 22 are engaged with the third rack 17 and the fourth rack 20 again. In the present embodiment, the teeth of the third gear 22, the fourth gear 23 and the fifth gear 24 are in a shuttle shape, and both ends are small and smooth; and the tooth tracks on the second rack 15 and the third rack 17 are in a horn shape with two gradually-enlarged openings, so that the gear and the rack can be movably engaged under the action of external force or a spring.

The implementation process of this embodiment is sequentially shown in fig. 3 to 5 to 7:

first, in the initial state as shown in fig. 3, double-lumen needle 7 is inserted into the heavy water bottle with both injection port 704 and discharge port 702 below the liquid level.

Then the push-pull handle 1 is pulled outwards, the injection piston rod 2 drives the injection piston head 6 to ascend, heavy water 16 starts to be sucked into the injection cavity 5, meanwhile, the exhaust piston rod 14 drives the exhaust piston head 10 to descend, air in the exhaust cavity 9 is exhausted until the exhaust piston head 10 is pressed against the bottom of the exhaust cavity 9 as shown in fig. 5, and a certain distance is reserved between the injection piston head 6 and the top of the injection cavity 5.

Finally, the pressing portion 1902 is pushed inward to push the first gear rack 19 to move backward along the sliding chute, so that the fourth gear 23 is engaged with the third rack 17 and the fifth gear 24 is engaged with the fourth rack 20, the push-pull handle 1 is pulled outward continuously, the injection piston rod 2 drives the discharge piston rod 14 to be pulled outward synchronously through the first co-directional driving mechanism, and a part of the heavy water 16 is sucked into the discharge cavity 9 as shown in fig. 7. The double-chamber syringe 4 is inverted, the double-chamber needle 7 is lifted, the push-pull handle 1 is pushed inwards to make the air in the injection chamber 5 and the discharge chamber 9 discharged from the double-chamber needle 7, and then the pressing part 1902 is released, and the first gear rack 19 rebounds and resets under the action of the first spring 21, so that the eyeball is ready to inject the heavy water 16.

Example 3

As shown in fig. 8, the double-chamber syringe 4 of the present embodiment is the same as that of embodiment 2, and is connected to the double-chamber catheter 25. The dual chamber syringe 4 in this embodiment also has an automatic linkage for linking the movement of the injection piston rod 2 and the discharge piston rod 14. The automatic linkage mechanism has the following functions: on one hand, after the double-cavity needle 7 is inserted into the eyeball, the discharging piston rod 14 is controlled to push the injection piston rod 2 inwards to be synchronously pulled outwards in the process of injecting heavy water 16 into the eyeball, so that the liquid in the eyeball is discharged synchronously with the injection; on the other hand, after the double-cavity needle 7 is inserted into the heavy water bottle, the discharging piston rod 14 is controlled to pull out the tail end of the heavy water 16 outside the injection piston rod 2, so that the discharging cavity 9 can synchronously extract a certain amount of heavy water 16, the heavy water 16 is enabled to fill corresponding channels of the double-cavity needle 7 and the double-cavity catheter 25, the delay caused by air expansion in the injection cavity 5, namely the effect of non-equivalent liquid extraction in the eyeball is eliminated by the low compression ratio of the filled heavy water 16, and the same-direction driving and the reverse-direction driving between the injection piston rod 2 and the discharging piston rod 14 are automatically switched according to the stroke of the injection piston rod 2, so that the operation is more convenient compared with the operation in the embodiment 2.

As shown in fig. 8, 9 and 12, the automatic linkage mechanism in this embodiment includes a fifth rack 27 disposed on the injection piston rod 2, a sixth rack 34 and a seventh rack 30 disposed on the discharge piston rod 14 at intervals, a second gear box 28 fixed at the rear end of the dual-chamber syringe 4, and a second gear carrier 29 slidably distributed in the second gear box 28 along the radial direction of the dual-chamber syringe 4. A second reverse driving component and a second same-direction driving component are arranged on the second gear rack 29 at intervals along the sliding direction of the second gear rack 29, the second reverse driving component is a sixth gear 36 rotatably arranged on the second gear rack 29, the second same-direction driving component is a seventh gear 37 and an eighth gear 33 rotatably arranged on the second gear rack 29 and meshed with each other, the eighth gear 33 is distributed on one side close to the fifth rack 27, the seventh gear 37 is distributed on one side close to the seventh rack 30, and the central axis directions of the sixth gear 36, the seventh gear 37 and the eighth gear 33 are all distributed parallel to the sliding direction of the second gear rack 29.

The second gear carrier 29 is similar to the first gear carrier 19 in structure and includes a second support plate 2903 and three second vertical plates 2902 fixed at intervals to the lower edge of the second support plate 2903. The second supporting plates 2903 are horizontally distributed, and the three second standing plates 2902 are parallel to each other and vertically distributed. The lower ends of the three second vertical plates 2902 are respectively provided with a second sliding block 2901, and the bottom of the second gear box 28 is correspondingly provided with a sliding groove matched with the second sliding block 2901 in a sliding way, so that the second gear rack 29 can integrally slide along the sliding groove. The three second vertical plates 2902 are correspondingly provided with shaft holes for the sixth gear 36, the seventh gear 37 and the eighth gear 33 to rotate.

As shown in fig. 9, a second spring 35 is provided on the left side of the second carrier 29, both ends of the second spring 35 are fixed to the left side wall of the second gear box 28 and the leftmost second upright plate 2902 of the second carrier 29, respectively, and the rightmost second upright plate 2902 of the second carrier 29 is in contact with the right side wall of the second gear box 28. At this time, both sides of the sixth gear 36 are respectively engaged with the sixth rack 34 and the fifth rack 27, the eighth gear 33 is engaged with the fifth rack 27, and the seventh gear 37 is located at a right position of the seventh rack 30. When the second carrier 29 is moved leftward by the external force, as shown in fig. 11 and 12, the sixth gear 36 is disengaged from the sixth rack 34 and the seventh gear 37 is engaged with the seventh rack 30. After the external force disappears, the second carrier 29 rebounds under the action of the second spring 35 and returns to the state shown in fig. 9.

The external force for driving the second carrier 29 against the elastic force of the second spring 35 in this embodiment comes from the guide convex strip 31. The guiding ribs 31 are fixed at the lower position of the injection piston rod 2 by L-shaped connecting ribs 32. The end of the guiding protrusion 31 corresponding to the second gear carrier 29 is wedge-shaped and can be in contact fit with the end of the second gear carrier 29 away from the second spring 35, so that the sliding of the second gear carrier 29 towards the second spring 35 is automatically controlled by the guiding protrusion 31 during the outward pulling of the injection piston rod 2. As shown in fig. 9, the guide ridge 31 and the right end of the second carrier 29 are separated from each other, and the initial position of the second carrier 29 is maintained by the second spring 35. As shown in fig. 11, after the guiding protrusion 31 continuously rises to the right end of the second gear frame 29 along with the injection piston rod 2, the second gear frame 29 is automatically pushed to move to the left against the resistance of the second spring 35.

The implementation process of this embodiment is sequentially shown in fig. 8 to 10 to 13:

first, in the initial state shown in fig. 8, double-lumen needle 7 is inserted into the heavy water bottle with both injection port 704 and discharge port 702 below the liquid level.

Then the push-pull handle 1 is pulled outwards, the injection piston rod 2 drives the injection piston head 6 to ascend, heavy water 16 starts to be sucked into the injection cavity 5, meanwhile, the exhaust piston rod 14 drives the exhaust piston head 10 to descend, air in the exhaust cavity 9 is exhausted until the exhaust piston head 10 is pressed against the bottom of the exhaust cavity 9 as shown in fig. 10, and a certain distance is left between the injection piston head 6 and the top of the injection cavity 5. As shown in fig. 11, at this time, the second carrier 29 is pressed toward the left by the guide rib 31, the second counter drive mechanism is deactivated, and the engagement of the second common drive mechanism is effected. The push-pull handle 1 is pulled outwards continuously, the injection guide rod and the discharge guide rod are pulled outwards synchronously, that is, as shown in fig. 13, the injection cavity 5 is filled with heavy water 16, and a small amount of heavy water 16 is pumped out of the discharge cavity 9.

Finally, the double-cavity injection tube 4 is inverted, the double-cavity needle 7 is lifted, and the push handle 1 is pushed inwards to enable air in the injection cavity 5 and the discharge cavity 9 to be discharged from the double-cavity needle 7. After the push-pull handle 1 is pushed inward until the guiding convex strip 31 is separated from the second gear frame 29, the second gear frame 29 rebounds and returns to the initial state under the action of the second spring 35, the engagement of the second reverse driving mechanism is effective, and the second same-direction driving mechanism is ineffective, so that the preparation for injecting the heavy water 16 into the eyeball is provided.

The embodiments in the present description are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A self-draining heavy water injection device for ophthalmic surgery, comprising a double-cavity needle (7), wherein the double-cavity needle (7) is provided with an injection channel (701) for injecting heavy water (16) into an eyeball and a discharge channel (703) for discharging liquid in the eyeball, and is characterized in that: the injection device also comprises a double-cavity injection tube (4), wherein the double-cavity injection tube (4) is provided with an injection cavity (5) communicated with the injection channel (701) and a discharge cavity (9) communicated with the discharge channel (703); an injection piston head (6) is arranged in the injection cavity (5) in a sliding manner, an injection piston rod (2) is connected to the injection piston head (6), a discharge piston head (10) is arranged in the discharge cavity (9) in a sliding manner, and the discharge piston head (10) is connected with a discharge piston rod (14), so that when the injection piston rod (2) is pushed into the double-cavity injection tube (4) to inject heavy water (16) in the injection cavity (5) into an eyeball, the discharge piston rod (14) is pulled outwards at the same time, and then intraocular liquid which is equal to the injected heavy water (16) can be extracted into the discharge cavity (9) so as to maintain the stability of intraocular pressure; a double-cavity catheter (25) is connected between the double-cavity injection tube (4) and the double-cavity needle (7);

the double-cavity injection cylinder (4) is also provided with a semi-automatic linkage mechanism for linking the movement of the injection piston rod (2) and the discharge piston rod (14), the semi-automatic linkage mechanism can be used for controlling the synchronous outward pulling of the discharge piston rod (14) in the process of pushing the injection piston rod (2) inwards to inject heavy water (16) into the eyeball, and the semi-automatic linkage mechanism is also used for controlling the synchronous outward pulling of the discharge piston rod (14) at the tail end of the injection piston rod (2) for the discharge cavity (9) to synchronously extract the heavy water (16);

the semi-automatic linkage mechanism comprises a third rack (17) arranged on the injection piston rod (2), a fourth rack (20) arranged on the discharge piston rod (14), a first gear box (18) fixed at the tail end of the dual-cavity injection cylinder (4) and a first gear rack (19) which is arranged between the third rack (17) and the fourth rack (20) and can be slidably distributed in the first gear box (18) along the radial direction of the dual-cavity injection cylinder (4); a first reverse driving component and a first reverse driving component are sequentially arranged on the first gear rack (19) along the sliding direction of the first gear rack (19), the first reverse driving component is a third gear (22) rotatably arranged on the first gear rack (19), the first reverse driving component is a fourth gear (23) and a fifth gear (24) which are rotatably arranged on the first gear rack (19) and are meshed with each other, the fourth gear (23) is distributed on one side close to the third rack (17), the fifth gear (24) is distributed on one side close to the fourth rack (20), and the central shaft directions of the third gear (22), the fourth gear (23) and the fifth gear (24) are all parallel to the sliding direction of the first gear rack (19);

an opening for one end of the first gear rack (19) to extend out is formed in the first gear box (18), the corresponding end of the first gear rack (19) can extend out of the opening to form a pressing part (1902), and after the first gear rack (19) is pressed into the first gear box (18) through the pressing part (1902), the fourth gear (23) is meshed with the third rack (17) and the fifth gear (24) is meshed with the fourth rack (20); a first spring (21) for pushing the pressing part (1902) of the first gear rack (19) out of the opening is arranged at the other end of the first gear box (18) in the sliding direction of the first gear rack (19), and after the pressing part (1902) of the first gear rack (19) is pushed out of the opening by the first spring (21), the two sides of the third gear (22) are respectively meshed with the third rack (17) and the fourth rack (20).

2. The self-draining heavy water injection device of claim 1, wherein: the first gear rack (19) is in an inverted chevron shape and comprises a first supporting plate (1904) and three first vertical plates (1903) fixed at the lower edge of the first supporting plate (1904) at intervals, sliding grooves for the three first vertical plates (1903) to be in sliding fit are formed in the bottom of the first gear box (18), and shaft holes for the third gear (22), the fourth gear (23) and the fifth gear (24) to be in rotating fit are correspondingly formed in the three first vertical plates (1903); the pressing portion (1902) is a cylindrical pressing handle fixed on a first vertical plate (1903) located at one end of the first support plate (1904), the shape of an opening on the first gear box (18) corresponds to the shape of the pressing handle, and the first spring (21) is arranged between the first vertical plate (1903) located at the other end of the first support plate (1904) and the side wall of the first gear box (18).

3. A self-draining heavy water injection device for ophthalmic surgery, comprising a double-cavity needle (7), wherein the double-cavity needle (7) is provided with an injection channel (701) for injecting heavy water (16) into an eyeball and a discharge channel (703) for discharging liquid in the eyeball, and is characterized in that: the injection device also comprises a double-cavity injection tube (4), wherein the double-cavity injection tube (4) is provided with an injection cavity (5) communicated with the injection channel (701) and a discharge cavity (9) communicated with the discharge channel (703); an injection piston head (6) is arranged in the injection cavity (5) in a sliding manner, an injection piston rod (2) is connected to the injection piston head (6), a discharge piston head (10) is arranged in the discharge cavity (9) in a sliding manner, and the discharge piston head (10) is connected with a discharge piston rod (14), so that when the injection piston rod (2) is pushed into the double-cavity injection tube (4) to inject heavy water (16) in the injection cavity (5) into an eyeball, the discharge piston rod (14) is pulled outwards at the same time, and then intraocular liquid which is equal to the injected heavy water (16) can be extracted into the discharge cavity (9) so as to maintain the stability of intraocular pressure; a double-cavity catheter (25) is connected between the double-cavity injection tube (4) and the double-cavity needle (7);

the double-cavity injection tube (4) is also provided with an automatic linkage mechanism for linking the movement of the injection piston rod (2) and the discharge piston rod (14), the automatic linkage mechanism is used for automatically controlling the synchronous outward pulling of the discharge piston rod (14) in the process of pushing the injection piston rod (2) inwards to inject heavy water (16) into the eyeball, and the automatic linkage mechanism is also used for controlling the synchronous outward pulling of the discharge piston rod (14) at the tail end of the heavy water (16) pulled out of the injection piston rod (2) so as to synchronously extract the heavy water (16) from the discharge cavity (9);

the automatic linkage mechanism comprises a fifth rack (27) arranged on the injection piston rod (2), a sixth rack (34) and a seventh rack (30) which are arranged on the discharge piston rod (14) at intervals, a second gear box (28) fixed at the tail end of the double-cavity injection tube (4) and a second gear rack (29) which is distributed in the second gear box (28) in a sliding manner along the radial direction of the double-cavity injection tube (4); a second reverse driving component and a second same-direction driving component are arranged on the second gear rack (29) at intervals along the sliding direction of the second gear rack (29), the second reverse driving component is a sixth gear (36) rotatably arranged on the second gear rack (29), the second same-direction driving component is a seventh gear (37) and an eighth gear (33) rotatably arranged on the second gear rack (29) and meshed with each other, the eighth gear (33) is distributed on one side close to the fifth rack (27), the seventh gear (37) is distributed on one side close to the seventh rack (30), the central axis directions of the sixth gear (36), the seventh gear (37) and the eighth gear (33) are all parallel to the sliding direction of the second gear rack (29), and the eighth gear (33) is meshed with the fifth rack (27);

a second spring (35) is arranged between one end of the second gear frame (29) in the self sliding direction and the corresponding side wall of the second gear box (28), the second spring (35) is used for maintaining that two sides of the sixth gear (36) are respectively meshed with the fifth rack (27) and the sixth rack (34), the eighth gear (33) is meshed with the fifth rack (27), and the seventh gear (37) is separated from the seventh rack (30); a guide convex strip (31) is arranged on the injection piston rod (2) along the length direction of the injection piston rod (2), the end part, corresponding to the second gear frame (29), of the guide convex strip (31) is wedge-shaped and can be in contact fit with the end part, far away from the second spring (35), of the second gear frame (29), so that the second gear frame (29) is automatically controlled to slide towards the direction of the second spring (35) by the guide convex strip (31) in the process of outwards pulling the injection piston rod (2), the sixth gear (36) is automatically controlled to be separated from the sixth rack (34), and the seventh gear (37) is automatically controlled to be meshed with the seventh rack (30).

4. The self-draining heavy water injection device of claim 3, wherein: the injection piston rod (2) is provided with a connecting rib plate (32) for fixing the guide convex strip (31), and the connecting rib plate (32) is L-shaped.