Grinding equipment and methods for rigid contact lenses

Abstract

This disclosure describes a polishing apparatus for rigid contact lenses, comprising a rotating body and a drive mechanism. The rotating body includes a cylindrical drum with a chamber, and blades disposed within the chamber and extending helically about the central axis of the drum. The chamber contains polishing balls and polishing slurry of substantially the same density as the rigid contact lenses. The drive mechanism drives the drum to rotate about its axis. In the polishing apparatus of this disclosure, blades are provided within the chamber of the drum. When the drive mechanism drives the drum to rotate, the polishing slurry within the chamber is agitated by the pushing action of the blades, causing friction between the polishing balls and the rigid contact lenses, thereby polishing the rigid contact lenses. In this case, by using a drum with a chamber capable of accommodating multiple rigid contact lenses, multiple rigid contact lenses can be polished simultaneously, thereby improving the polishing efficiency of the rigid contact lenses.

Description

Technical Field

[0001] This disclosure generally relates to an apparatus and process for polishing or grinding, and more specifically to a grinding device and method for hard contact mirrors. Background Technology

[0002] In optometry, common products used to improve vision include eyeglasses and contact lenses. Among these, rigid contact lenses are gradually becoming a popular choice.

[0003] The manufacturing process of rigid contact lenses typically includes lens molding, lens polishing, and lens prescription adjustment. In current polishing processes, after lens molding, one of the front or back surfaces of the lens is attached to a base, leaving the other side exposed. A polishing head equipped with a soft abrasive material, such as a soft abrasive cloth, is then used to polish the exposed side of the lens. Throughout the polishing process, workers need to manually process the lens in multiple batches using abrasive cloths with different grit sizes to achieve the desired smoothness on the contact lens surface.

[0004] The problem that arises from this is that, in the aforementioned prior art, since the lenses are ground one by one and the front and back surfaces of the lenses are ground one by one, the existing lens processing efficiency is low. Summary of the Invention

[0005] The present invention was made in view of the above-mentioned state of the prior art, and its purpose is to provide a grinding apparatus and grinding method that can improve the processing efficiency of rigid contact mirrors.

[0006] To this end, the first aspect of this disclosure provides a polishing apparatus for rigid contact lenses, comprising a rotating body and a driving mechanism. The rotating body includes a cylindrical drum with a chamber and a paddle disposed in the chamber and extending helically about the central axis of the drum. The chamber contains polishing balls and polishing fluid of substantially the same density as the rigid contact lens. The driving mechanism drives the drum to rotate about an axis.

[0007] In the grinding apparatus according to the first aspect of this disclosure, a paddle is provided in the chamber of the drum. When the drive mechanism drives the drum to rotate, the grinding fluid in the chamber is agitated by the pushing action of the paddle, causing friction between the grinding balls and the hard contact lens, thereby grinding the hard contact lens. In this case, by using a drum with a chamber capable of accommodating multiple hard contact lenses, multiple hard contact lenses can be ground simultaneously, thereby improving the grinding efficiency of the hard contact lenses.

[0008] Based on the polishing slurry with the same density as the rigid contact lens and the curved structure of the rigid contact lens, the rigid contact lenses will not violently collide with each other and cause scratches during the polishing process. The polishing of the rigid contact lens will be mainly accomplished by the polishing slurry agitated by the blades. Furthermore, in the polishing equipment according to the first aspect of this disclosure, optionally, the radius of the polishing ball is not greater than the radius of curvature of the central optical zone of the rigid contact lens. Polishing balls of this size can polish areas of the rigid contact lens with large radii of curvature, thereby ensuring that the polishing equipment can polish all areas of the rigid contact lens.

[0009] Additionally, in the grinding apparatus according to the first aspect of this disclosure, optionally, the radius of the grinding ball is 4mm-7mm. This radius range is particularly suitable for the processing of corneal contact lenses, orthokeratology lenses, and scleral lenses.

[0010] Furthermore, in the polishing apparatus according to the first aspect of this disclosure, optionally, the Shore hardness of the polishing ball is 40D-90D. Combined with the aforementioned radius design of the polishing ball, when the Shore hardness of the polishing ball is within the aforementioned range, the hardness of the polishing ball is similar to that of common materials for rigid contact lenses. The polishing ball ensures that, while achieving slight impact to polish the rigid contact lens, it will not generate excessive impact force that could cause pitting or even cracking on the surface of the rigid contact lens.

[0011] Furthermore, in the grinding apparatus according to the first aspect of this disclosure, the blade may optionally be a flange formed on the inner wall of the drum. This reduces the likelihood of undesirable collisions between the hard contact mirror and the blade during the grinding process.

[0012] Additionally, in the grinding apparatus according to the first aspect of this disclosure, optionally, the flange extends from one end of the roller along a cylindrical surface to the other end, and the top surface of the flange is smoothly rounded. In this case, by extending the flange from one end of the roller along a cylindrical surface to the other end, the blades can generate a pushing action along the line extending from one end of the roller to the other end, thereby facilitating the grinding of rigid contact mirrors at different positions within the chamber.

[0013] Furthermore, in the grinding apparatus according to the first aspect of this disclosure, optionally, the number of blades is multiple, and the multiple blades are evenly arranged around the central axis of the drum. This increases the degree of agitation of the grinding slurry and improves the uniformity of agitation.

[0014] Additionally, in the grinding apparatus according to the first aspect of this disclosure, optionally, the sum of the helical angles of each blade about the central axis of the drum is 360 degrees. In this case, the blade extends circumferentially around the drum, ensuring that the blade generates appropriate agitation of the grinding fluid throughout the entire circumference of the drum, thereby ensuring that the blade generates a pushing effect along the circumferential line of the drum.

[0015] Additionally, in the polishing apparatus according to the first aspect of this disclosure, optionally, the blades extend helically about the central axis of the drum and spiral along the geometric center line of the blades, with the spiral angle formed by the blades spiraling around the geometric center line being 60 degrees to 120 degrees. In this case, by configuring the blades to have a component along the radial direction of the drum, a pushing action on the polishing fluid can be generated along the radial direction of the drum, thereby facilitating more thorough polishing of the hard contact mirror.

[0016] Additionally, in the polishing apparatus according to the first aspect of this disclosure, optionally, the polishing fluid includes alumina particles and at least one of glycerol, glycerol, and trihydroxypropane. Preferably, the polishing fluid contains alumina particles, glycerol, glycerol, and trihydroxypropane. By adjusting the proportions of these components to achieve a desired density in the polishing fluid (e.g., substantially the same density as a rigid contact lens), it is beneficial to suppress violent collisions between rigid contact lenses during the polishing process.

[0017] Additionally, in the grinding apparatus according to the first aspect of this disclosure, optionally, the rotating body includes circumferential teeth arranged circumferentially around the outer periphery of the drum, and the driving mechanism includes a plurality of drive shafts with drive gears, the drive gears cooperating with the circumferential teeth.

[0018] In addition, in the grinding apparatus according to the first aspect of this disclosure, optionally, the plurality of drive shafts are evenly arranged along the circumference of the roller.

[0019] A second aspect of this disclosure also provides a method for polishing a rigid contact lens, comprising: configuring a rotating body, the rotating body including a cylindrical roller having a chamber, and a paddle disposed in the chamber and extending helically about the central axis of the roller; configuring an polishing slurry with substantially the same density as the rigid contact lens, and polishing balls with a density greater than that of the polishing slurry; adding the polishing slurry, polishing balls, and the rigid contact lens to be polished into the chamber; and driving the rotating body to rotate about an axis so that the polishing slurry and polishing balls polish the rigid contact lens.

[0020] In the polishing method according to the second aspect of this disclosure, a paddle is provided in the chamber of the drum. When the drum is driven to rotate, the polishing fluid in the chamber is agitated by the paddle, causing friction between the polishing balls and the polishing particles in the polishing fluid and the rigid contact lens, thereby polishing the rigid contact lens. In this case, by using a drum with a chamber capable of accommodating multiple rigid contact lenses, multiple rigid contact lenses can be polished simultaneously, thereby improving the polishing efficiency of the rigid contact lenses.

[0021] Furthermore, in the grinding method according to the second aspect of this disclosure, optionally, the grinding slurry is divided into multiple equal volumes, and the number of hard contact lenses to be ground is divided into multiple portions, with one portion of grinding slurry and one portion of hard contact lenses constituting one batch of material, and multiple batches of material are added to the chamber in batches. In this case, by adding multiple hard contact lenses in equal batches to the chamber, it is possible to facilitate orderly grinding within the chamber.

[0022] Furthermore, in the grinding method according to the second aspect of this disclosure, optionally, when adding batches of material to the chamber, the grinding slurry and the rigid contact lens are added sequentially. In this case, by adding the grinding slurry first and then the rigid contact lens, unwanted collisions between different batches of rigid contact lenses can be effectively reduced.

[0023] Furthermore, in the grinding method according to the second aspect of this disclosure, optionally, the rotating body rotates at a first predetermined speed during a first predetermined period, and then rotates at a second predetermined speed less than the first predetermined speed during a second predetermined period following the first predetermined period. In this case, relatively fast grinding is performed in the early stage, and relatively slow grinding is performed in the later stage, thereby facilitating a balance between grinding speed and grinding effect.

[0024] In addition, in the grinding method according to the second aspect of this disclosure, optionally, the ratio of the grinding liquid to the grinding balls is 50 to 150 grinding balls per liter of grinding liquid.

[0025] According to this disclosure, the grinding equipment and grinding method can improve the grinding efficiency of hard contact lenses. Attached Figure Description

[0026] Figure 1A This is a perspective view illustrating the rigid contact mirror involved in this embodiment example;

[0027] Figure 1B This is a cross-sectional schematic diagram illustrating the rigid contact mirror involved in this embodiment example.

[0028] Figure 2This is a schematic diagram illustrating a scenario where a hard contact mirror is polished using polishing fluid, as described in this embodiment example.

[0029] Figure 3A This is a perspective view of the grinding apparatus involved in this embodiment example; Figure 3B This is an exploded schematic diagram showing the grinding apparatus involved in this embodiment example.

[0030] Figure 4 This is a half-sectional view showing the rotating body involved in this embodiment example.

[0031] Figure 5A This is a schematic diagram showing the arrangement of multiple blades on the inner wall of the drum in this embodiment example; Figure 5B This is a perspective view illustrating a first example of a single blade involved in this embodiment. Figure 5C This is a perspective view illustrating a second example of a single blade involved in this embodiment. Figure 5D This is a perspective view illustrating a third example of a single blade involved in this embodiment.

[0032] Figure 6 This is a schematic diagram showing a rotating body carrying a contact mirror, polishing fluid, and polishing balls, as described in this embodiment example.

[0033] Figure 7 This is a schematic flowchart illustrating the grinding method involved in this embodiment example.

[0034] Explanation of reference numerals in the attached figures:

[0035] L…Contact lens, L1…Central optical zone, L2…Peripheral optical zone, L3…Adapter zone

[0036] 100…grinding equipment,

[0037] 10…rotating body, 12…roller, 14…circumferential teeth, 16…blade,

[0038] 20…Drive mechanism, 22…Drive shaft, 24…Motor, 26…Drive gear, 28…Transmission unit, 282…Transmission pulley, 284…Transmission belt,

[0039] CA…the central axis of the drum, S…one path followed by the blades in a helical extension around CA, R1…the direction of rotation of the drum, R2…one helical direction of the blades, R3…another helical direction of the blades, F1…flow along the central axis, F2…flow along the radial direction. Detailed Implementation

[0040] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description, the same reference numerals are used for the same parts, and repeated descriptions are omitted. Furthermore, the drawings are merely schematic diagrams, and the proportions of the parts or the shapes of the parts may differ from the actual figures.

[0041] It should be noted that the terms "comprising" and "having" and any variations thereof in this disclosure, such as a process, method, system, product, or device that includes or has a series of steps or units, are not necessarily limited to those steps or units that are explicitly listed, but may include or have other steps or units that are not explicitly listed or that are inherent to such processes, methods, products, or devices.

[0042] The rigid contact lenses involved in this disclosure can be any rigid contact lenses made of rigid materials that are suitable for wearing on the ocular surface, such as rigid corneal contact lenses, orthokeratology lenses (i.e., corneal reshaping lenses), scleral lenses, corneo-scleral lenses (Corneo-scleral lenses or semi-scleral lenses).

[0043] The embodiments of this disclosure relate to a grinding apparatus and a grinding method for rigid contact lenses, which can perform batch grinding of rigid contact lenses.

[0044] Figure 1A This is a perspective view illustrating an illustrative rigid contact mirror L involved in this embodiment example; Figure 1B This is a cross-sectional schematic diagram showing the rigid contact mirror L involved in this embodiment example.

[0045] In this embodiment, the rigid contact lens L is shown in the form of an orthokeratology (OK) lens. As shown in FIG1, the rigid contact lens L can be worn on the eyeball and has a front surface facing forward when worn, and a rear surface opposite to the front surface (see Figure 1A The posterior surface of the rigid contact lens L can be a concave surface that matches the surface of the eyeball, and can include a central optical region L1, a peripheral optical region L2 surrounding the central optical region L1, and an adapter region L3 surrounding the peripheral optical region L2, connected sequentially from the center outwards (see...). Figure 1B Other forms of rigid contact lenses may be divided into different zones, but generally they all contain a central optical zone for correcting or adjusting visual acuity. The number of zones a rigid contact lens can be divided into, and the size of each zone, does not affect the applicability of this disclosure.

[0046] In some examples, the diameter of the rigid contact lens L can be 12mm-26mm, such as 12mm, 14mm, 15mm, 16mm, 18mm, 20mm, 22mm, 24mm, or 26mm. Additionally, in some examples, the diameter of the central optical zone of the rigid contact lens L can be 5mm to 10mm, such as 5mm, 5.5mm, 6mm, 8mm, 9mm, or 10mm.

[0047] In this disclosure, the manufacturing process of a rigid contact lens L may include steps such as a lens forming process, a lens grinding process (also known as a "polishing process"), and a lens power adjustment process. Specifically, the lens forming process may involve performing operations such as turning on the lens substrate to substantially shape the lens substrate into the desired form. The lens grinding process may include preliminary grinding for roughing the formed lens, and further grinding for finishing after the preliminary grinding. The lens power adjustment process is a fine-tuning step, which may involve performing operations such as thinning at specific locations on the lens.

[0048] In some examples, the above-described lens polishing process can be performed using polishing equipment equipped with polishing fluid, as disclosed below. Figure 2 This is a schematic diagram illustrating a scenario where a hard contact mirror L is polished using polishing fluid, as described in this embodiment example. See also... Figure 2 The rigid contact lens L can be placed in a polishing slurry. By agitating the polishing slurry, the polishing particles and polishing balls suspended in the slurry are made to rub against the rigid contact lens L, thereby polishing the rigid contact lens L.

[0049] To improve grinding efficiency, hard contact lenses L can be added in batches to the agitated grinding slurry for roughing, thereby increasing grinding efficiency in the initial grinding step. Subsequent finishing is then performed using a larger mesh abrasive cloth for further grinding.

[0050] Therefore, this embodiment proposes a polishing device based on polishing fluid to perform batch preliminary polishing of hard contact mirrors L, thereby improving polishing efficiency. Figure 3A This is a perspective view showing the grinding apparatus 100 according to an example of this embodiment; Figure 3B This is an exploded schematic diagram showing the grinding apparatus 100 involved in this embodiment example.

[0051] In this embodiment, the grinding apparatus 100 may include a rotating body 10 and a drive mechanism 20 (see [link]). Figure 3A The rotating body 10 may include a drum 12 with a chamber, and the chamber may contain polishing fluid. A drive mechanism 20 is used to drive the drum 12 to rotate.

[0052] In the grinding apparatus 100 according to this embodiment, when the drive mechanism 20 drives the drum 12 to rotate, the grinding fluid in the chamber is simultaneously agitated, causing the grinding particles, grinding balls, etc., suspended in the grinding fluid to rub against the hard contact lens L, thereby grinding the hard contact lens L. In this case, by using a drum 12 having a chamber capable of accommodating multiple hard contact lenses L for grinding, multiple hard contact lenses L can be ground simultaneously, thereby improving the grinding efficiency of the hard contact lens L.

[0053] In this embodiment, the roller 12 can be cylindrical. Furthermore, the roller 12 can rotate about its central axis CA. Additionally, the chamber of the roller 12 can be generally cylindrical, such as a cylinder or a hexagonal prism. A closable opening can be provided on the wall of the roller 12 to allow the discharge of processed rigid contact lenses, etc. The roller 12 is preferably made of a transparent rigid material so that operators can observe the state of the rigid contact lenses L in the internal chamber in real time. The central axis of the chamber and the central axis of the roller 12 can be collinear.

[0054] In some examples, the rotating body 10 includes circumferential teeth 14 arranged circumferentially around the outer periphery of the roller 12 (see [reference]). Figure 3B The drive mechanism 20 can use the circumferential teeth 14 to drive the roller 12 to rotate.

[0055] Specifically, the drive mechanism 20 may include a drive shaft 22 and a motor 24, the motor 24 being used to actuate the drive shaft 22 to rotate. A drive gear 26 that meshes with the circumferential teeth 14 may be provided on the drive shaft 22. The motor 24 actuates the drive shaft 22 to rotate, and the drive gear 26 on the drive shaft 22 can drive the roller 12 to rotate by meshing with the circumferential teeth 14.

[0056] The number of circumferential teeth 14 can be one or more (see Figure 3B For driving stability considerations, there can be two circumferential teeth 14, and the two circumferential teeth 14 are respectively arranged near both ends of the roller 12. In this case, by driving the roller 12 synchronously at both ends, driving stability can be improved. In addition, the number of drive gears 26 provided on the drive shaft 22 can be the same as the number of circumferential teeth 14.

[0057] In some examples, the number of drive shafts 22 can be multiple (see...) Figure 3A or Figure 3B Multiple drive shafts 22 can be evenly arranged along the circumference of the roller 12, and the drive gears 26 of each drive shaft 22 can all mesh with the circumferential teeth 14. See also Figure 3A and Figure 3BIn the illustrated embodiment, the number of drive shafts 22 can be three. The three drive shafts 22 can encircle the roller 12 in such a way that the drive gear 26 meshes with the circumferential teeth 14. In this case, the three drive shafts 22 can be used both to drive the roller 12 and to support it.

[0058] In other embodiments, the number of drive shafts 22 may be one, and the drive mechanism 20 may also include a support portion (not shown) for supporting the roller 12, on which the roller 12 supported can rotate freely.

[0059] Additionally, the drive mechanism 20 may also include a transmission unit 28 (see...) Figure 3A The transmission unit 28 can be used to link the output shaft of the motor 24 with multiple drive shafts 22. In some examples, the transmission unit 28 may include multiple drive pulleys 282 and a drive belt 284. The number of drive pulleys 282 may be the same as the number of drive shafts 22, and the multiple drive pulleys 282 may be respectively disposed on multiple drive shafts 22 and located at the same end. The drive belt 284 can link the multiple drive pulleys 282 (see [link]). Figure 3A The motor 24 can actuate one of the drive wheels 282 of the transmission unit 28 to rotate, and the transmission belt 284 can drive the other drive wheels 282 to rotate in conjunction.

[0060] In another preferred embodiment (not shown), the drive shaft 22 and the corresponding drive gear 26 of the drive mechanism 20 are only disposed below the roller 12; meanwhile, a roller (not shown) is disposed above the roller 12 to prevent the roller 12 from moving up and down during operation. Figure 3A The direction shown in the diagram, for example, is where the roller is located. Figure 3A The position of the drive gear 26 above the roller 12. (And) Figure 3A Unlike the previous example, in this embodiment, the roller can move towards or away from the drum 12. The mechanism that drives the roller 12 can be any type of drive mechanism. For example, the drive mechanism is a lifting mechanism mounted above the drum (e.g., on the ceiling of a factory building), and the lifting mechanism is connected to the support shaft on which the roller is mounted. Alternatively, the drive mechanism can be a telescopic mechanism on one or both sides of the drum, and the lifting mechanism is connected to the support shaft on which the roller is mounted.

[0061] The roller can be used only as described above, such as Figure 3A A single row of drive gears, or multiple rows, can be arranged at the position of the drive gear 26 above the roller 12, located on the left and right sides of the roller 12. In this case, the drive mechanism that drives the rollers to move toward or away from the roller 12 is similar to that described above, and will not be repeated here.

[0062] Advantageously, the drive mechanism with rollers makes it easier for workers to hoist the roller 12, and facilitates cleaning and maintenance of the roller 12, etc.

[0063] The example of the drive mechanism 20 in this embodiment is not limited to this. In this embodiment, the drive mechanism 20 is mainly used to drive the drum 12 to rotate so that the grinding fluid is agitated. Those skilled in the art will understand that other common mechanisms for driving the drum 12 to rotate can also be applied to the grinding equipment 100 involved in this embodiment.

[0064] In order to make the grinding fluid more fully agitated when the drum 12 rotates, the rotating body 10 according to this embodiment also includes a mechanism that can apply a pushing force to the grinding fluid to form a flow when the drum 12 rotates. Figure 4 This is a half-sectional view showing the rotating body 10 according to the example of this embodiment. The half-sectional view shows the blade 16 according to this embodiment and schematically shows the path of the blade 16 extending helically around the central axis CA and the flow formed by the pushing action of the blade 16. The path of the blade 16 extending helically around the central axis CA is shown in the schematic diagram as the center line S in the length direction of the blade 16.

[0065] In various embodiments, the mechanism described above that can apply a pushing force to the polishing fluid to form a flow when the drum 12 rotates can be a paddle 16 disposed in the chamber (see Figure 4 The blade 16 can exert a pushing force on the polishing slurry when the drum 12 rotates, so that the polishing slurry is agitated to form a flow along a preset direction, thereby polishing the hard contact mirror L.

[0066] In some examples, the blade 16 is configured to exert a pushing force on the polishing fluid along the axial direction of the drum 12 as the drum 12 rotates (described in detail later), so that the polishing fluid forms a flow F1 along the axial direction of the drum 12 (see [link to relevant documentation]). Figure 4 Additionally, the blade 16 is configured to apply a pushing force to the polishing fluid along the radial direction of the drum 12 as the drum 12 rotates (described in detail later), so that the polishing fluid forms a flow F2 along the radial direction of the drum 12 (see [link to relevant documentation]). Figure 4 ).

[0067] In the grinding apparatus 100 of this embodiment, by providing a paddle 16 in the chamber of the drum 12, when the drum 12 rotates, the grinding fluid in the chamber is agitated by the pushing action of the paddle 16 to form a flow along a preset direction. This causes the abrasive particles, abrasive balls, etc., suspended in the grinding fluid to move relative to the hard contact mirror L, thereby generating friction and grinding the hard contact mirror L. In this case, by using the paddle 16 to apply a pushing action to the grinding fluid, the agitation of the grinding fluid can be enhanced, thereby improving the grinding efficiency.

[0068] In order to generate a consistent pushing force on the abrasive fluid on the same circumference orthogonal to the central axis CA, the impeller 16 can extend helically around the central axis CA of the drum 12 (see...). Figure 4 The helical surface formed by the blade 16 spiraling around the central axis CA of the drum 12 can have a component orthogonal to the axial direction. See [reference needed] in this case. Figure 4 When the drum 12 rotates in the direction indicated by R1 in the figure, the blade 16 can exert a pushing force on the grinding fluid along the axial direction of the drum 12, so that the grinding fluid forms a flow F1 along the axial direction of the drum 12.

[0069] Figure 5A This is a schematic diagram illustrating the arrangement of multiple blades 16 on the inner wall of the drum 12 according to an example of this embodiment. In some embodiments, the number of blades 16 is multiple (see...). Figure 5A This further enhances the agitation of the polishing slurry. Multiple blades 16 can be evenly arranged around the central axis CA of the drum 12. In this configuration, it helps to create a consistent pushing force on the polishing slurry on the same circumference orthogonal to the central axis CA, thereby improving the polishing consistency of the hard contact mirror L at different locations.

[0070] In some embodiments, the sum of the helical angles of each blade 16 about the central axis CA of the drum 12 can be 360 ​​degrees. In other words, the circumferential extension of each blade 16 in the drum 12 forms a closed circle. In this case, the blade 16 extends circumferentially around the drum 12, thereby enabling the axial pushing force generated by the blade 16 within the drum 12 to revolve around the central axis CA, thus creating a consistent pushing force on the abrasive fluid.

[0071] In some examples, the number of blades 16 can be three, and the helical angle of each blade 16 about the central axis CA of the roller 12 is 120 degrees.

[0072] In some embodiments, the blade 16 may be a flange formed on the inner wall of the drum 12 (see...). Figure 4 or Figure 5AThis reduces the likelihood of unwanted collisions between the hard contact lens L and the blade 16 during the grinding process. Furthermore, the flange extends from one end of the roller 12 along the cylindrical surface defined by the inner wall of the roller 12 to the other end, and the top surface of the flange is smoothly rounded. In this case, by extending the flange from one end of the roller 12 along the cylindrical surface to the other end, the blade 16 can generate a pushing action along the line extending from one end of the roller 12 to the other, thereby facilitating the grinding of hard contact lenses L at different positions within the chamber.

[0073] Figure 5B This is a perspective view showing a first example of a single blade 16 involved in this embodiment. Figure 5C This is a perspective view illustrating a second example of a single blade 16 involved in this embodiment. Figure 5D This is a perspective view illustrating a third example of a single blade 16 involved in this embodiment. Figure 5B , Figure 5C and Figure 5D In the embodiment shown, line S represents the view of the path (center line S) followed by the helical extension of the blade 16 around the central axis CA in the flat unfolded state of the inner wall of the drum 12.

[0074] See Figure 4 The blade 16 can extend helically around the central axis CA of the drum 12. In some examples, in a view of the drum 12 in its unfolded state, the blade 16 can appear as a column with beveled ends, such as a quadrangular prism (see [reference]). Figure 5B This simplifies the design complexity of the blade 16.

[0075] In some embodiments, in order to more thoroughly agitate the grinding slurry and improve grinding efficiency, the impeller 16 also simultaneously spirals around the centerline S of the impeller 16 (see...). Figure 5C or Figure 5D The centerline S can be the geometric centerline of the blade 16 extending along its length. In some examples, the helical angle formed by the blade 16 helicating around the geometric centerline S can be 60 to 120 degrees, for example, 60, 70, 80, 90, 100, 110, or 120 degrees.

[0076] The helical surface formed by the blade 16 spiraling around the geometric center line S can have a component orthogonal to the radial direction. In this case, the blade 16 is configured to have a component along the radial direction of the roller 12, see [reference needed]. Figure 5B and combined Figure 4When the drum 12 rotates in the direction indicated by R1, the blade 16 can push the polishing fluid in the radial direction of the drum 12 so that the polishing fluid forms a flow F2 in the radial direction of the drum 12, thereby helping to polish the hard contact mirror L more thoroughly.

[0077] exist Figure 5C In the example shown, blade 16 can be spiraled clockwise around the geometric center line S, thereby forming a helical surface with a component orthogonal to the radial direction (see [reference]). Figure 5C Specifically, one end of the blade 16 is fixed, and the other end is twisted in the direction indicated by R2, and the angle of twisting in the direction indicated by R2 can be from 60 degrees to 120 degrees.

[0078] exist Figure 5D In the example shown, blade 16 can rotate counterclockwise around the geometric center line S, thereby forming a helical surface with a component orthogonal to the radial direction (see [reference]). Figure 5D Specifically, one end of the blade 16 is fixed, and the other end is twisted in the direction indicated by R3, and the angle of twisting in the direction indicated by R3 can be from 60 degrees to 120 degrees.

[0079] For the sake of uniform agitation, the blade 16 can spiral at a constant speed around the geometric center line S in the direction extending along the blade 16.

[0080] It should be understood that although the blade described above in conjunction with the accompanying drawings is in the form of a thin sheet (i.e., shown in the drawings as having a rectangular cross-section), this is not necessarily the only implementation according to the inventive concept of this disclosure. The "blade" according to this disclosure can also be in other forms, for example, in the transverse cross-section of the drum, the blade can be generally triangular, or other forms.

[0081] Figure 6 This is a schematic diagram showing the rotating body 10 of this embodiment carrying a rigid contact mirror L, polishing fluid and polishing balls.

[0082] In this embodiment, to minimize lens damage, the density of the polishing slurry can be configured to suspend the rigid contact lens L in the slurry (see [reference]). Figure 6 Specifically, the polishing slurry and the rigid contact lens L can be substantially of the same density. In this case, on the one hand, the rigid contact lens L can be suspended in the polishing slurry, thereby suppressing undesirable collisions between the rigid contact lens L and the inner wall of the roller 12; on the other hand, the rigid contact lens L can be substantially stationary relative to the polishing slurry, thereby reducing undesirable disordered movement of the rigid contact lens L in the polishing slurry.

[0083] In some examples, the polishing slurry may include alumina particles and at least one of glycerol, glycerol, and trihydroxypropane. More preferably, the polishing slurry includes alumina particles, glycerol, glycerol, and trihydroxypropane. This prepares a polishing slurry with a density substantially equal to that of the rigid contact lens L. In this case, when the polishing slurry is agitated, due to the density difference between the alumina particles and the slurry, a velocity difference exists between the flow generated by the agitation of the slurry and the movement of the alumina particles (i.e., relative movement occurs). This causes relative movement between the rigid contact lens L (which is substantially stationary relative to the polishing slurry) and the alumina particles, resulting in friction upon contact. Thus, the friction between the alumina particles and the rigid contact lens L facilitates polishing of the rigid contact lens L.

[0084] In addition, to increase the friction experienced by the hard contact mirror L during the grinding process, the chamber may optionally contain grinding balls (see [link]). Figure 6 The density of the grinding balls can also be greater than that of the grinding fluid, so that when the grinding fluid is agitated, the grinding balls can rub against the hard contact mirror L, thereby grinding the hard contact mirror L.

[0085] In some embodiments, to ensure that all locations of the rigid contact lens L can be ground, the radius of the abrasive ball may not be greater than the radius of curvature of any region of the rigid contact lens L. For example, the radius of the abrasive ball may not be greater than the radius of curvature of the central optical region L1 of the rigid contact lens L. This facilitates grinding of all regions of the rigid contact lens L. Furthermore, the radius of the abrasive ball can be 4mm-7mm. The abrasive ball is used in the processing of corneal contact lenses, orthokeratology lenses, and scleral lenses. The specific radius of the abrasive ball is selected to be slightly smaller than the central optical region of the corresponding rigid contact lens; specifically, the radius of the abrasive ball is set to be between 0.05mm and 1mm smaller than the central optical region of the corresponding rigid contact lens. Under the premise of satisfying the grinding and polishing requirements, abrasive balls of this size will not generate excessive impact force.

[0086] The abrasive ball is preferably designed to produce a grinding effect on the hard contact lens L, while minimizing the possibility of damage to the hard contact lens L. For this purpose, the Shore hardness of the abrasive ball is 40D-90D. In this case, by designing the Shore hardness of the abrasive ball to be similar to the common hardness of the hard contact lens L, it is beneficial to grind hard contact lenses L of common hardness and to reduce the possibility of damage to the hard contact lens L. In some examples, the abrasive ball can be made of materials such as plexiglass or low-density polyethylene resin.

[0087] In some examples, the length of the roller 12 can be set to any value within the range of 150mm-350mm, such as 170mm, 200mm, etc. Additionally, the diameter of the roller 12 can be any value within the range of 80-150mm, such as 100mm, 120mm, etc. In some examples, each liter of polishing fluid can contain 10-50 hard contact lenses L. Furthermore, each liter of polishing fluid can contain 50-100 polishing balls.

[0088] Figure 7 This is a schematic flowchart illustrating the grinding method involved in this embodiment example.

[0089] The polishing method disclosed herein includes: preparing a carrier for performing polishing (step S100); preparing polishing slurry (step S200); placing the polishing slurry and the hard contact lens L on the carrier (step S300); and operating the carrier to perform polishing (step S400).

[0090] The carrier for performing grinding configured in step S100 can be the rotating body 10 described herein. As described above, the rotating body 10 may include a cylindrical drum 12 with a cavity, and a blade 16 disposed within the cavity and extending helically about the central axis of the drum 12.

[0091] The polishing slurry prepared in step S200 can be the same as the polishing slurry described herein. The density of the polishing slurry can be substantially equal to the density of the rigid contact lens L. In this case, on the one hand, the rigid contact lens L can be suspended in the polishing slurry, thereby suppressing undesirable collisions between the rigid contact lens L and the inner wall of the roller 12; on the other hand, the rigid contact lens L can be substantially stationary relative to the polishing slurry, thereby reducing undesirable disordered movement of the rigid contact lens L in the polishing slurry.

[0092] To increase friction, step S200 may further include: preparing abrasive particles with a density greater than that of the grinding fluid, such as the abrasive particles described herein. Additionally, step S200 may further include: preparing grinding balls with a density greater than that of the grinding fluid, such as the grinding balls described herein. Optionally, the ratio of grinding fluid to grinding balls may be 50 to 150 grinding balls per liter of grinding fluid.

[0093] Step S300 may include adding polishing slurry, polishing balls, and rigid contact lenses L to be polished into the chamber. In step S300, the polishing slurry may be divided into multiple equal volumes, and the rigid contact lenses L to be polished may be divided into multiple equal quantities. Each portion of polishing slurry and each portion of rigid contact lenses constitutes a batch of material, and multiple batches of material may be added to the chamber in batches. In this case, by adding multiple rigid contact lenses in equal quantities to the chamber in batches, it is possible to facilitate orderly polishing within the chamber. In some examples, the lenses in the multiple batches of material are arranged at equal intervals.

[0094] Furthermore, in step S300, when adding each batch of material to the chamber, the polishing slurry and the rigid contact lens L can be added sequentially. In this case, by adding the polishing slurry first and then the rigid contact lens L, unwanted collisions between different batches of rigid contact lenses L can be effectively reduced.

[0095] In some embodiments, in step S300, firstly, a measured amount of polishing slurry and polishing balls in an agitated state are added to the drum 12; then, one or more rigid contact lenses L are added to the drum 12; then, a measured amount of polishing slurry and polishing balls in an agitated state are added to the drum 12 again; the above steps are repeated until the drum 12 is full. Generally, according to the design of placing about 50 contact lenses in 1L of polishing slurry, the lenses can be added in 8-10 batches.

[0096] In other embodiments, in step S300, firstly, a grinding fluid is quantitatively added to the roller 12; then, grinding balls are added to the roller 12; next, the material already in the roller 12 is appropriately agitated, and then one or more rigid contact lenses L are added to the roller 12; then, a grinding fluid is quantitatively added to the roller 12 again; the above steps are repeated until the roller 12 is full. Similar to the above embodiments, the lenses can be added in 8-10 batches.

[0097] In some other embodiments, in step S300, firstly, a grinding fluid is quantitatively added to the drum 12; then, one or more rigid contact mirrors L are added to the drum 12; next, grinding balls are added to the drum 12 and the existing material in the drum 12 is agitated; then, a grinding fluid is quantitatively added to the drum 12 again; the above steps are repeated until the drum 12 is fully loaded.

[0098] In step S400, the rotating body 10 is driven to rotate about an axis so that the polishing slurry and polishing balls polish the hard contact mirror L. The rotating body 10 can be driven to rotate using the drive mechanism 20 described herein in step S400.

[0099] Additionally, step S400 may further include: the rotating body 10 rotating at a first predetermined speed during a first predetermined period, and the rotating body 10 rotating at a second predetermined speed less than the first predetermined speed during a second predetermined period after the first predetermined period. In this case, relatively fast grinding is performed in the early stage, and relatively slow grinding is performed in the later stage, thereby facilitating a balance between grinding speed and grinding effect. In some examples, the duration of the first predetermined period can be 3-5 hours, which can be set according to the material. The duration of the second predetermined period can be 3-6 hours, which can be set according to the processing accuracy requirements. The first predetermined speed can be 40-70 rpm. The second predetermined speed can be 50-80 rpm.

[0100] While the present invention has been specifically described above in conjunction with the accompanying drawings and embodiments, it is to be understood that the above description does not limit the present invention in any way. Those skilled in the art can make modifications and variations to the present invention as needed without departing from the essential spirit and scope of the invention, and all such modifications and variations fall within the scope of the present invention.

Claims

1. A grinding apparatus for rigid contact lenses, characterized in that, The device includes a rotating body and a driving mechanism. The rotating body includes a cylindrical drum with a chamber and a blade disposed within the chamber and extending helically about the central axis of the drum. The blade is a flange formed on the inner wall of the drum. The chamber contains abrasive balls and an abrasive slurry with a density substantially equal to that of the rigid contact lens. The density of the abrasive balls is greater than that of the abrasive slurry. The driving mechanism drives the drum to rotate about an axis. The blade is configured to apply a pushing force to the abrasive slurry when the drum rotates, causing the abrasive slurry to be agitated to form a flow in a predetermined direction to abrade the rigid contact lens. Abrasion refers to polishing the rigid contact lens by agitating the abrasive slurry to cause friction between the abrasive slurry, the abrasive balls, and the rigid contact lens.

2. The grinding equipment according to claim 1, characterized in that, The radius of the grinding ball is not greater than the radius of curvature of the central optical zone of the rigid contact mirror.

3. The grinding equipment according to claim 2, characterized in that, The radius of the grinding ball is 4mm-7mm.

4. The grinding apparatus according to any one of claims 1-3, characterized in that, The Shore hardness of the grinding ball is 40D-90D.

5. The grinding equipment according to claim 1, characterized in that, The flange extends from one end of the roller along the cylindrical surface to the other end, and the top surface of the flange is smoothly transitioned.

6. The grinding equipment according to claim 5, characterized in that, The number of blades is multiple, and the multiple blades are evenly arranged around the central axis of the drum.

7. The grinding equipment according to claim 6, characterized in that, The sum of the helical angles of each blade around the central axis of the drum is 360 degrees.

8. The grinding apparatus according to claim 1 or 7, characterized in that, The blade extends spirally around the central axis of the drum and spirals along the geometric center line of the blade, with the spiral angle formed by the blade spiraling around the geometric center line being 60 degrees to 120 degrees.

9. The grinding equipment according to claim 1, characterized in that, The grinding fluid includes alumina particles and at least one of glycerol, glycerol, and trihydroxypropane.

10. The grinding equipment according to claim 1, characterized in that, The rotating body includes circumferential teeth arranged circumferentially around the outer periphery of the roller, and the driving mechanism includes a plurality of drive shafts with drive gears, the drive gears cooperating with the circumferential teeth.

11. The grinding apparatus according to claim 10, characterized in that, The plurality of drive shafts are evenly arranged along the circumference of the roller.

12. A method for polishing a rigid contact mirror, characterized in that, include: A rotating body is configured, comprising a cylindrical drum with a chamber, and blades disposed within the chamber and extending helically around the central axis of the drum. The blades are flanges formed on the inner wall of the drum, and the blades are configured to apply a pushing force to the grinding fluid when the drum rotates, so that the grinding fluid is agitated to form a flow in a predetermined direction. The polishing slurry has a density substantially the same as that of the rigid contact mirror, and the polishing balls have a density greater than that of the polishing slurry. Add polishing fluid, polishing balls, and the hard contact mirror to be polished into the chamber; The rotating body is driven to rotate around an axis so that the polishing slurry and polishing balls polish the rigid contact mirror. The polishing refers to polishing the rigid contact mirror by agitating the polishing slurry so that the polishing slurry and polishing balls rub against the rigid contact mirror.

13. The grinding method according to claim 12, characterized in that, The grinding slurry is divided into multiple portions of equal volume, and the number of hard contact lenses to be ground is also divided into multiple portions. Each portion of grinding slurry and each portion of hard contact lens constitutes a batch of material, and multiple batches of material are added to the chamber in batches.

14. The grinding method according to claim 13, characterized in that, When each batch of material is added to the chamber, the grinding fluid and the rigid contact lens are added in sequence.

15. The grinding method according to claim 12, characterized in that, The rotating body rotates at a first predetermined speed during a first predetermined period, and rotates at a second predetermined speed less than the first predetermined speed during a second predetermined period after the first predetermined period.

16. The grinding method according to claim 12, characterized in that, The grinding fluid and the grinding balls are mixed in a ratio of 50 to 150 grinding balls per liter of grinding fluid.

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