Electromagnetic air injection mechanism for non-contact tonometer

Abstract

The utility model relates to the technical field of tonometer, in particular to an electromagnetic air injection mechanism for a non-contact tonometer, and mainly solves the technical problems that the existing non-contact tonometer is complex in structure and large in device size. The electromagnetic air injection mechanism comprises a cylinder body; the upper cover plate is hermetically fixed at the upper end opening of the cylinder body and is provided with an air injection port; the lower cover plate is fixed at the lower end opening of the cylinder body and is provided with a mounting hole; the piston is of a stepped shaft structure, the large-diameter section of the stepped shaft is slidably connected into the cylinder body, and the small-diameter section of the stepped shaft penetrates through the mounting hole; and the coil is wound on the outer side of the cylinder body and is used for driving the piston to move upwards when being electrified. The electromagnetic air injection mechanism adopts the coil to generate a magnetic field to drive the piston to move, structures such as a rotating electromagnet, a crank and a sliding block do not need to be arranged, the structure is simpler, and the device size is smaller.

Description

Technical Field

[0001] This utility model relates to the field of tonometer technology, and in particular to an electromagnetic jet mechanism for a non-contact tonometer. Background Technology

[0002] Tonometers are now widely used to measure intraocular pressure in the human eye. Measuring intraocular pressure provides a reference for the diagnosis and treatment of glaucoma and related eye diseases. Among them, non-contact tonometers are gaining increasing attention and usage due to their advantages such as comfort and no risk of cross-infection. Non-contact tonometers generally use the movement of a piston to generate compressed air. This compressed air enters the air chamber through an air tube and is then sprayed onto the cornea through a specific nozzle, flattening the cornea and thus measuring intraocular pressure.

[0003] Most existing non-contact tonometers use a rotating electromagnet as a power source, which then drives a piston via a crank-slider mechanism to generate compressed air. However, this structure is relatively complex and the device is quite large due to the need for components such as the rotating electromagnet, crank, and slider. Utility Model Content

[0004] To overcome the technical shortcomings of existing non-contact tonometers, such as complex structure and large device size, this utility model provides an electromagnetic jet mechanism for non-contact tonometers.

[0005] The electromagnetic jet mechanism for a non-contact tonometer provided by this utility model includes:

[0006] The cylinder block is open at both the top and bottom ends;

[0007] The upper cover plate is sealed and fixed to the upper opening of the cylinder body and is provided with an air jet port, which communicates with the inner cavity of the cylinder body;

[0008] The lower cover plate is fixed to the lower end opening of the cylinder body and has a mounting hole. The mounting hole is coaxial with the cylinder body and its diameter is smaller than the inner diameter of the cylinder body so that the lower cover plate forms an annular shoulder placed inside the cylinder body.

[0009] The piston has a stepped shaft structure. The large-diameter section of the stepped shaft is slidably connected to the cylinder body, and the small-diameter section of the stepped shaft passes through the mounting hole. When the piston is in the initial state, the stepped surface of the stepped shaft overlaps the annular shoulder.

[0010] A coil, wound around the outside of the cylinder, is used to drive the piston upward when energized.

[0011] Optionally, the cylinder body has an air volume hole in the middle of its axial direction, and the air volume hole is located above the piston in the initial state.

[0012] Optionally, the outer wall of the cylinder is provided with three annular lugs, which are located at both ends and the middle of the cylinder respectively, so that the outer wall of the cylinder forms two annular slots. The coil is provided with two sets and is wound in the two annular slots respectively. The air volume hole is located at the annular lug in the middle.

[0013] Optionally, the air volume orifice is an arc-shaped orifice.

[0014] Optionally, a spring may also be included, which is located at the top of the inner cavity of the cylinder.

[0015] Optionally, the spring is tower-shaped with its larger end embedded in the inner edge of the top surface of the cylinder.

[0016] Optionally, the upper cover plate is bolted to the upper end of the cylinder and a sealing ring is pressed between them, the sealing ring being located outside the large end of the spring.

[0017] Optionally, the left and right ends of the upper cover plate are bent downward to form a first overlapping portion, and the left and right ends of the lower cover plate are bent upward to form a second overlapping portion. The first and second overlapping portions on the left side are connected to a left side plate, and the first and second overlapping portions on the right side are connected to a right side plate.

[0018] Optionally, the upper cover plate, lower cover plate, left side plate, and right side plate are all made of magnetically conductive material.

[0019] Optionally, the left side plate is bolted to the first and second overlapping portions located on the left side, and the right side plate is bolted to the first and second overlapping portions located on the right side.

[0020] The technical solution provided by this utility model has the following advantages compared with the prior art:

[0021] This invention provides an electromagnetic air jet mechanism for a non-contact tonometer. During use, the air jet port faces upwards. An energized coil wound around the cylinder generates a magnetic field, driving a piston upwards to produce compressed air, which is then ejected from the air jet port. After ejection, the coil is de-energized, and the piston returns to its original position under gravity. This electromagnetic air jet mechanism uses a coil to generate a magnetic field that drives the piston, eliminating the need for rotating electromagnets, cranks, sliders, or other similar structures, resulting in a simpler structure and a smaller device size. Attached Figure Description

[0022] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with the present invention and, together with the description, serve to explain the principles of the present invention.

[0023] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 A three-dimensional structural diagram of the electromagnetic jet mechanism in an embodiment of this utility model;

[0025] Figure 2 This is a two-dimensional view of the jet port side of the electromagnetic jet mechanism in an embodiment of the present invention;

[0026] Figure 3 express Figure 2 Sectional view at point AA;

[0027] Figure 4 This is a three-dimensional structural diagram of the cylinder body in an embodiment of the present invention.

[0028] In the picture:

[0029] 1. Cylinder block; 2. Upper cover plate; 3. Injection port; 4. Lower cover plate; 5. Annular shoulder; 6. Piston; 7. Coil; 8. Air volume orifice; 9. Annular lug; 10. Spring; 11. Sealing ring; 12. First overlapping part; 13. Second overlapping part; 14. Left side plate; 15. Right side plate; 16. Annular groove; 17. Annular placement groove. Detailed Implementation

[0030] To better understand the above-mentioned objectives, features, and advantages of this utility model, the solution of this utility model will be further described below. It should be noted that, unless otherwise specified, the embodiments of this utility model and the features thereof can be combined with each other.

[0031] Many specific details are set forth in the following description in order to provide a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein; obviously, the embodiments in the specification are only some embodiments of the present invention, and not all embodiments.

[0032] The following is combined Figures 1 to 4 The specific embodiments of this utility model will be described in detail below.

[0033] This embodiment provides an electromagnetic jet mechanism for a non-contact tonometer, including a cylinder 1, an upper cover plate 2, a lower cover plate 4, a piston 6, and a coil 7.

[0034] The cylinder body 1 has open ends at both the top and bottom, meaning that the cylinder body 1 has a cylindrical structure.

[0035] The upper cover plate 2 is sealed and fixed to the upper opening of the cylinder body 1 and is provided with a jet port 3, which is connected to the inner cavity of the cylinder body 1.

[0036] It should be noted that during use, jet port 3 is connected to the nozzle via a hose, and compressed air is ejected through the nozzle.

[0037] Specifically, the upper cover plate 2 is connected to the upper end of the cylinder body 1 by bolts and a sealing ring 11 is pressed between them. The upper cover plate 2 and the upper end of the cylinder body 1 are fixed by bolts and sealed by the sealing ring 11.

[0038] More specifically, an annular groove 16 can be opened on the upper end face of the cylinder body 1, and then the sealing ring 11 can be embedded in the annular groove 16. The annular groove 16 can limit the sealing ring 11, which is more conducive to maintaining the stability of the structure.

[0039] Specifically, the outer wall of the cylinder body 1 is provided with three annular lugs 9. The three annular lugs 9 are located at both ends and the middle of the cylinder body 1 respectively, so that the outer wall of the cylinder body 1 forms two annular slots. The annular slots are mainly used for winding the coil 7.

[0040] Furthermore, the cylinder body 1 has an air volume hole 8 in the middle of its axial direction, which is located above the piston 6 in its initial state. When the piston 6 is below the air volume hole 8, air can still overflow from the air volume hole 8 as the piston 6 moves upward. Air compression only begins when the piston 6 blocks the air volume hole 8, so the air volume hole 8 can ensure that the volume pushed out by the piston 6 is equal each time.

[0041] Specifically, when the outer wall of the cylinder 1 is provided with three annular lugs 9, the air volume hole 8 is located at the annular lug 9 in the middle, which can prevent the coil 7 from blocking the air volume hole 8.

[0042] More specifically, the air volume orifice 8 is an arc-shaped orifice.

[0043] The lower cover plate 4 is fixed to the lower end opening of the cylinder body 1 and has a mounting hole. The mounting hole is coaxial with the cylinder body 1 and its diameter is smaller than the inner diameter of the cylinder body 1 so that the lower cover plate 4 forms an annular shoulder 5 placed inside the cylinder body 1.

[0044] Among them, piston 6 has a stepped shaft structure. The large-diameter section of the stepped shaft is slidably connected in the cylinder 1, and the small-diameter section of the stepped shaft passes through the mounting hole. When piston 6 is in the initial state, the stepped surface of the stepped shaft overlaps on the annular shoulder 5.

[0045] It should be noted that if piston 6 only contains the large-diameter section, when piston 6 moves upward, piston 6 will disengage from the lower cover plate 4, and the magnetic field generated by the coil 7 at the bottom will not be able to act on piston 6. Therefore, this solution requires piston 6 to be equipped with a stepped shaft structure so that the magnetic field generated by the coil 7 at the bottom can act on piston 6 throughout the entire stroke of piston 6, providing piston 6 with a greater driving force.

[0046] The coil 7 is wound around the outside of the cylinder 1 and is used to drive the piston 6 upward when energized.

[0047] Specifically, coil 7 has two sets, which are wound in two annular slots respectively.

[0048] It is easy to understand that when coil 7 is energized, it will generate a magnetic field. Piston 6 is made of magnetic material, and the magnetic field generated by coil 7 will drive piston 6 to move upward to compress air.

[0049] In addition, the electromagnetic jet mechanism of this embodiment is also equipped with a spring 10, which is located at the top of the inner cavity of the cylinder 1. The spring 10 has two functions: first, it can buffer the piston 6 to prevent the piston 6 from colliding with the upper cover plate 2 and causing structural damage, and also to prevent the piston 6 from colliding with the upper cover plate 2 and generating a lot of noise; second, after the coil 7 is de-energized, residual magnetism will remain for a short time. When the piston 6 abuts against the spring 10, the spring 10 can generate a force in the opposite direction to counteract the effect of the residual magnetism, so that the piston 6 can be smoothly reset.

[0050] Specifically, the spring 10 is tower-shaped with its larger end embedded in the inner edge of the top surface of the cylinder 1.

[0051] More specifically, an annular groove 17 can be opened on the upper end face of the cylinder body 1 to engage the large end of the spring 10. However, it should be noted that the sealing ring 11 should be located outside the large end of the spring 10 to ensure the sealing between the upper cover plate 2 and the cylinder body 1.

[0052] Furthermore, the electromagnetic jet mechanism of this embodiment also includes a left side plate 14 and a right side plate 15, with the following specific structure: both ends of the upper cover plate 2 are bent downwards to form a first overlapping portion 12, and both ends of the lower cover plate 4 are bent upwards to form a second overlapping portion 13. The first overlapping portion 12 and the second overlapping portion 13 on the left side are connected to the left side plate 14, and the first overlapping portion 12 and the second overlapping portion 13 on the right side are connected to the right side plate 15. The left side plate 14 and the right side plate 15 can protect the coil 7, preventing damage from impacts caused by the exposed coil 7.

[0053] Specifically, the upper cover plate 2, lower cover plate 4, left side plate 14 and right side plate 15 are all made of magnetically conductive material, which can confine the magnetic field within the enclosed space and enhance the magnetic field strength in the cylinder 1 chamber.

[0054] Specifically, the left side plate 14 is bolted to the first overlapping portion 12 and the second overlapping portion 13 located on the left side, and the right side plate 15 is bolted to the first overlapping portion 12 and the second overlapping portion 13 located on the right side.

[0055] The working principle of the electromagnetic jet mechanism used in this embodiment for a non-contact tonometer is as follows:

[0056] When in use, place the device vertically with the jet port 3 facing upwards; the coil 7 is energized to generate a magnetic field, which drives the piston 6 to move upwards. When the piston 6 blocks the air flow hole 8, it begins to compress air, causing a fixed volume of compressed air to be ejected from the jet port 3; as the piston 6 moves upwards, it gradually compresses the spring 10. When the jetting ends, the coil 7 is de-energized, and the piston 6 moves downwards under the elastic force of the spring 10 and gravity, eventually causing the stepped surface of the piston 6 to overlap the annular shoulder 5, waiting for the next jetting.

[0057] The above are merely specific embodiments of this utility model, enabling those skilled in the art to understand or implement this utility model. Although detailed descriptions have been provided with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments, and they should all be covered by the protection scope of the claims.

Claims

1. An electromagnetic jet mechanism for a non-contact tonometer, characterized in that, include: The cylinder body (1) has open ends at both the top and bottom; The upper cover plate (2) is sealed and fixed to the upper opening of the cylinder body (1) and is provided with a jet port (3), which is connected to the inner cavity of the cylinder body (1); The lower cover plate (4) is fixed to the lower end opening of the cylinder body (1) and has a mounting hole. The mounting hole is coaxial with the cylinder body (1) and its diameter is smaller than the inner diameter of the cylinder body (1) so that the lower cover plate (4) forms an annular shoulder (5) placed inside the cylinder body (1). The piston (6) has a stepped shaft structure. The large diameter section of the stepped shaft is slidably connected in the cylinder (1), and the small diameter section of the stepped shaft passes through the mounting hole. When the piston (6) is in the initial state, the stepped surface of the stepped shaft overlaps the annular shoulder (5). A coil (7) is wound around the outside of the cylinder (1) and is used to drive the piston (6) upward when energized.

2. The electromagnetic jet mechanism for a non-contact tonometer according to claim 1, characterized in that, The cylinder (1) has an air volume hole (8) in the middle of its axial direction, and the air volume hole (8) is located above the piston (6) in its initial state.

3. The electromagnetic jet mechanism for a non-contact tonometer according to claim 2, characterized in that, The outer side wall of the cylinder (1) is provided with three annular lugs (9). The three annular lugs (9) are located at both ends and the middle of the cylinder (1) respectively, so that the outer side wall of the cylinder (1) forms two annular slots. The coil (7) is provided with two sets and is wound in the two annular slots respectively. The air volume hole (8) is located at the annular lug (9) in the middle.

4. The electromagnetic jet mechanism for a non-contact tonometer according to claim 3, characterized in that, The gas flow orifice (8) is an arc-shaped orifice.

5. The electromagnetic jet mechanism for a non-contact tonometer according to any one of claims 1 to 4, characterized in that, It also includes a spring (10) located at the top of the inner cavity of the cylinder (1).

6. The electromagnetic jet mechanism for a non-contact tonometer according to claim 5, characterized in that, The spring (10) is tower-shaped and its large end is embedded in the inner edge of the top surface of the cylinder (1).

7. The electromagnetic jet mechanism for a non-contact tonometer according to claim 6, characterized in that, The upper cover plate (2) is bolted to the upper end of the cylinder (1) and a sealing ring (11) is pressed between them. The sealing ring (11) is located outside the large end of the spring (10).

8. The electromagnetic jet mechanism for a non-contact tonometer according to any one of claims 1 to 4, characterized in that, The upper cover plate (2) is bent downward at both ends to form a first overlapping part (12), and the lower cover plate (4) is bent upward at both ends to form a second overlapping part (13). The first overlapping part (12) and the second overlapping part (13) on the left side are connected to the left side plate (14), and the first overlapping part (12) and the second overlapping part (13) on the right side are connected to the right side plate (15).

9. The electromagnetic jet mechanism for a non-contact tonometer according to claim 8, characterized in that, The upper cover plate (2), lower cover plate (4), left side plate (14) and right side plate (15) are all made of magnetic material.

10. The electromagnetic jet mechanism for a non-contact tonometer according to claim 8, characterized in that, The left side plate (14) is bolted to the first overlapping part (12) and the second overlapping part (13) located on the left side, and the right side plate (15) is bolted to the first overlapping part (12) and the second overlapping part (13) located on the right side.

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