Micro-injection device

Abstract

The utility model discloses a micro-injection device, which belongs to the field of experimental devices and can avoid the problem that a piston shaft deforms due to the fact that the piston shaft is too thin, so that a user can more smoothly carry out micro-volume fluid injection. The device comprises a needle head, a tube body, a piston head, a piston shaft with threads and a nut, the needle head is mounted at the front end of the tube body; the piston is installed at one end of the piston shaft with the threads and is in close fit with the inner side of the pipe body, so that when the piston head slides relative to the interior of the pipe body, no gas or liquid overflows from the contact position of the piston head and the pipe body. The piston shaft with the threads is matched with the nut; when the piston shaft with the threads rotates, the nut and the pipe body are kept relatively static; the rear end of a handle of the threaded piston shaft is provided with a marked line passing through the circle center, and the volume of injection fluid is calculated according to the number of half-circle rotation of the shaft. According to the device, the accuracy of the volume of the injected fluid can be improved, and a user can more accurately and easily inject a trace volume of fluid.

Description

Technical Field

[0001] The utility model belongs to the field of experimental devices, in particular to a micro-injection device. Background Art

[0002] At present, microinjection devices all use the method of designing the inner diameter of the syringe tube to be very thin to achieve the purpose of microinjection and improve the accuracy of injection volume. However, this method causes the piston shaft to be too thin and easy to deform, resulting in the microinjection device being extremely inconvenient to use in actual experiments. The deformation of the piston shaft can easily affect the normal injection operation and even the accuracy of the injection volume. At the same time, the operation of pushing the piston shaft itself is difficult to control, which will also reduce the accuracy of the experiment.

[0003] In view of the above reasons, it is necessary to provide a new type of microinjection device. This experimental device can avoid the problem of the piston shaft being too thin and easy to deform, and avoid the method of directly pushing the piston shaft to inject fluid, thereby allowing users (such as teachers and students) to perform the operation of micro-volume fluid injection more smoothly. Utility Model Content

[0004] The utility model provides a micro-injection device, which can avoid the problem of deformation of a piston shaft due to being too thin, and allows a user to more smoothly perform micro-volume fluid injection.

[0005] In order to solve the above technical problems, the utility model adopts the following technical solutions:

[0006] A microinjection device, comprising a needle, a tube body, a piston head, a threaded piston shaft, and a nut; the needle is mounted on one end of the tube body; the piston is mounted on one end of the threaded piston shaft and is tightly matched with the inside of the tube body, so that when the piston head and the inside of the tube body slide relative to each other, no gas or liquid will overflow from the contact point between the piston head and the tube body; the threaded piston shaft is matched with the nut; the nut is located at the other end of the tube body and remains relatively still with the tube body; the thread of the threaded piston shaft is a single-line and triangular thread with a tooth angle of 60°;

[0007] In the above structure, the threaded piston shaft has a thread with a certain angle (1.5°-20°) of thread lead, and the nut and the threaded piston shaft have the same specifications so that the two can match each other; the outer diameter of the nut is larger than the inner diameter of the tube body, so that the nut will not enter the tube body with the piston shaft; the rear end of the tube body has two parallel baffles, and the nut just matches the two baffles, so that the nut and the tube body remain relatively stationary; the rear end of the handle of the threaded piston shaft has a marking line passing through the center of the circle, so that the user can calculate the volume of the injected fluid according to the number of half-circles of the shaft rotation.

[0008] Beneficial effects: The utility model provides a microinjection device, which has the following advantages compared with the prior art:

[0009] (1) The device provided by the utility model can avoid the method of reducing the inner diameter of the tube body to improve the accuracy of the injected fluid volume, thereby avoiding the problem of the piston shaft being too thin. When the user injects the fluid, the accuracy of the injected fluid volume will not be affected by the deformation of the piston shaft, and the volume of the fluid injection can be more easily controlled;

[0010] (2) The device provided by the utility model can absorb the fluid by pulling the piston shaft backward and inject the liquid forward by rotating the piston shaft, so that the user can efficiently draw the fluid into the tube when sucking the fluid, and can accurately inject the fluid according to the required volume when injecting the fluid, avoiding the difficulty in controlling the injection volume due to directly pushing the piston shaft to inject the fluid. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 It is a three-dimensional schematic diagram of the microinjection device in the embodiment of the utility model;

[0012] Figure 2 It is a schematic diagram of the longitudinal section structure of the microinjection device in the embodiment of the utility model;

[0013] Figure 3 It is an assembly diagram of a threaded piston shaft component and a nut component in a microinjection device in an embodiment of the utility model and a right side view schematic diagram of the two components after being reassembled;

[0014] Figure 4 It is a three-view schematic diagram of a nut in a microinjection device in an embodiment of the utility model;

[0015] Figure 5 It is a three-view schematic diagram of the tube body in the microinjection device in the embodiment of the utility model;

[0016] Figure 6 It is a schematic diagram of a front view and a cross-sectional view of the tube body and the nut after being assembled in the microinjection device in the embodiment of the utility model;

[0017] Figure 7 This is one of the front views of the microinjection device in the embodiment of the utility model in the use state;

[0018] Figure 8 This is the second front view of the microinjection device in the embodiment of the utility model in the use state;

[0019] Fig. 9 This is the third front view of the microinjection device in the embodiment of the utility model in the use state;

[0020] Fig.10This is the fourth front view of the microinjection device in the embodiment of the utility model in the use state;

[0021] Fig.11 This is the fifth front view of the microinjection device in the embodiment of the utility model in the use state;

[0022] In the figure, 1 is a needle, 2 is a tube body, 3 is a piston, 4 is a piston shaft with a thread, and 5 is a nut. DETAILED DESCRIPTION

[0023] like Figure 1-Figure 2 As shown, a microinjection device comprises: a needle 1, a tube body 2, a piston 3, a piston shaft 4 with a thread, and a nut 5; the needle 1 is installed at the front end of the tube body 2; the piston 3 is tightly matched with the inside of the tube body 2, so that when the piston 3 and the inside of the tube body 2 slide relative to each other, no gas or liquid will overflow from the contact point between the piston head and the tube body; the shaft body of the threaded piston shaft 4 has a thread with a certain angle (1.5°-20°) of thread lead angle, the thread is a single-line and triangular thread, and the tooth angle is 60°; the nut 5 has the same specifications as the threaded piston shaft 4, so that the two The outer diameter of the nut 5 is larger than the inner diameter of the tube body 2, so that the nut 5 will not enter the tube body 2 with the threaded piston shaft 4. There are two parallel baffles at the rear end of the tube body 2, and the nut 5 can just match with the two baffles, so that the nut 5 and the tube body 2 remain relatively still; there is a marking line passing through the center of the circle at the rear end of the handle of the threaded piston shaft 4, and the user can calculate the volume of the injected fluid according to the number of half-circles of the shaft rotation; the device can improve the accuracy of the injected fluid volume and allow the user to inject a trace volume of fluid more accurately and easily.

[0024] like Figure 7 As shown, when the piston is pushed to the front end of the tube body, the air inside the tube body is exhausted and fluid can be pumped.

[0025] like Figure 8 As shown, when it is necessary to pump fluid, the handle behind the piston shaft is directly pulled to achieve the purpose of pumping fluid.

[0026] like Fig. 9 and Fig.10 As shown, the nut on the piston shaft is then rotated to near the rear end baffle of the tube body and the angle of the nut is adjusted to ensure that when the piston shaft is pushed forward until the nut is against the rear end surface of the tube body, the nut just fits well with the two baffles at the rear end of the tube body, so as to achieve the purpose of keeping the nut and the tube body relatively still when the piston shaft is rotated.

[0027] like Fig.11 As shown, when starting to inject the fluid, hold the tube body and twist the handle behind the piston shaft so that the piston shaft pushes the piston forward to squeeze out the fluid. When the mark line behind the handle returns to the initial position again, the piston shaft rotates half a circle.

[0028] When the piston shaft rotates, the piston moves forward; assuming that the thread lead angle is θ, the thread diameter of the threaded part of the piston shaft is d, and the inner diameter of the tube body is D, when the piston shaft rotates half a circle, it is equivalent to the object moving on the inclined plane. In the horizontal direction, it moves a distance L= When πd, the upward movement distance is πdtanθ, that is, the distance the piston moves forward is πdtanθ, then the volume of injected fluid is π 2 D 2 dtanθ; The minimum graduation value of the injection volume of the microinjection device is π 2 D 2 dtanθ.

[0029] The above embodiments are only preferred embodiments of the present invention, which are only used to explain the technical solution of the present invention rather than to limit it. Although the present invention is described in detail with reference to the preferred embodiments, those skilled in the art should understand that they can still modify or replace the technical solution of the present invention, and these modifications or equivalent replacements also fall within the protection scope of the present invention.

Claims

1. A microinjection device, characterized in that: It includes a needle, a tube body, a piston head, a threaded piston shaft, and a nut; the needle is installed at the front end of the tube body; the piston head is installed at one end of the threaded piston shaft and is tightly matched with the inner side of the tube body, so that when the piston head and the inside of the tube body slide relative to each other, no gas or liquid will overflow from the contact point between the piston head and the tube body; the threaded piston shaft is matched with the nut; when the threaded piston shaft rotates, the nut and the tube body remain relatively still.

2. The microinjection device according to claim 1, characterized in that: The shaft body of the threaded piston shaft is provided with threads with a certain thread lead angle, which cooperates with the nut.

3. The microinjection device according to claim 1 or 2, characterized in that: The thread of the threaded piston shaft is a single-line and triangular thread.

4. The microinjection device according to claim 3, characterized in that: The thread angle of the thread is 60°.

5. The microinjection device according to claim 2, characterized in that: The thread lead angle is 1.5°-20°.

6. The microinjection device according to claim 1, characterized in that: Two parallel baffles are installed at the rear end of the tube body to cooperate with the nut, so that the nut and the tube body remain relatively still.

7. The microinjection device according to claim 1 or 6, characterized in that: The outer diameter of the nut is greater than the inner diameter of the pipe body.

8. The microinjection device according to claim 1 or 2, characterized in that: The rear end of the handle of the threaded piston shaft is provided with a marking line passing through the center of the circle, and the volume of the injected fluid is calculated according to the number of half-turns of the shaft rotation.

9. The microinjection device according to claim 8, characterized in that: When the threaded piston shaft rotates half a turn, the volume of fluid injected is Where θ is the thread lead angle, d is the thread pitch diameter of the threaded portion of the piston shaft, and D is the inner diameter of the tube body.

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