阅读说明：本技术 双面研磨机及双面研磨方法 (Double-side grinding machine and double-side grinding method ) 是由 吴康 王庆 杨洪望 何锐楠 魏金波 胡秀媚 于 2019-07-31 设计创作，主要内容包括：本发明公开了一种双面研磨机及双面研磨方法,属于磨削工艺技术领域。双面研磨机包括上磨盘、下磨盘、行星轮、太阳轮、外齿轮、第一驱动装置和第二驱动装置；在太阳轮的边缘设置内齿圈；在外齿轮的边缘设置外齿圈；行星轮分别与内齿圈和外齿圈啮合；第一驱动装置与太阳轮传动连接,第二驱动装置与外齿轮传动连接；双面研磨机在打磨蓝宝石衬底时交替处于第一状态和第二状态,第一驱动装置和第二驱动装置中的至少一个在第一状态时的转速与在第二状态时的转速不同,并且下磨盘中行星轮与内齿圈啮合处在第一状态时和在第二状态时总的磨损量,与下磨盘中行星轮与外齿圈啮合处在第一状态时和在第二状态时总的磨损量相等。本发明可改善下磨盘表面平整性。(The invention discloses a double-sided grinding machine and a double-sided grinding method, and belongs to the technical field of grinding processes. The double-sided grinding machine comprises an upper grinding disc, a lower grinding disc, a planet wheel, a sun wheel, an outer gear, a first driving device and a second driving device; an inner gear ring is arranged at the edge of the sun gear; an outer gear ring is arranged at the edge of the outer gear; the planet gear is respectively meshed with the inner gear ring and the outer gear ring; the first driving device is in transmission connection with the sun gear, and the second driving device is in transmission connection with the external gear; the double-side lapping machine is alternately in a first state and a second state when lapping the sapphire substrate, the rotation speed of at least one of the first driving device and the second driving device in the first state is different from that in the second state, and the total abrasion loss in the lower grinding disc when the planetary wheel is meshed with the inner gear ring in the first state and in the second state is equal to the total abrasion loss in the lower grinding disc when the planetary wheel is meshed with the outer gear ring in the first state and in the second state. The invention can improve the surface smoothness of the lower grinding disc.)

1. A double-side grinder, characterized in that it comprises an upper grinding disc (11), a lower grinding disc (12), a planetary gear (13), a sun gear (14), an external gear (15), a first drive means (16) and a second drive means (17); the upper grinding disc (11) and the lower grinding disc (12) are coaxial and are arranged oppositely; the sun wheel (14) is coaxially arranged between the upper grinding disc (11) and the lower grinding disc (12), and an inner gear ring (18) is arranged on the edge of the sun wheel (14); the outer gear (15) is coaxially arranged on one side, away from the upper grinding disc (11), of the lower grinding disc (12), and an outer gear ring (19) is arranged on the edge of the outer gear (15); the planet wheels (13) are arranged on the surface of the lower grinding disc (12) opposite to the upper grinding disc (11), and the planet wheels (13) are respectively meshed with the inner gear ring (18) and the outer gear ring (19); the first driving device (16) is in transmission connection with the sun gear (14), and the second driving device (17) is in transmission connection with the outer gear (15); the double-side lapping machine is alternately in a first state and a second state when lapping a sapphire substrate, the rotation speed of at least one of the first drive device (16) and the second drive device (17) in the first state is different from the rotation speed in the second state, and the total amount of wear of the lower lapping disc (12) at the meshing part (A) of the planetary gear (13) and the inner gear ring (18) in the first state and in the second state is equal to the total amount of wear of the lower lapping disc (12) at the meshing part (B) of the planetary gear (13) and the outer gear ring (19) in the first state and in the second state.

2. A double side grinder as claimed in claim 1, characterised in that the rotational speed of the first and second drive means in the first state and the rotational speed in the second state are determined as follows:

determining the rotation speed of the planet gear in the first state, the rotation speed of the inner gear ring in the first state and the rotation speed of the outer gear ring in the first state based on process requirements;

obtaining the revolution rotating speed of the planet wheel in the first state according to the rotation rotating speed of the planet wheel in the first state based on the relation between the rotation rotating speed and the revolution rotating speed of the planet wheel;

determining the abrasion loss when the planetary gear in the lower grinding disc is meshed with the inner gear ring in the first state and the abrasion loss when the planetary gear in the lower grinding disc is meshed with the outer gear ring in the first state according to the rotation speed and the revolution speed of the planetary gear in the first state;

based on the relationship between the rotation speed and revolution speed of the planet gear, which is equal to the total abrasion loss when the planet gear is engaged with the inner gear ring in the lower grinding disc in the first state and in the second state, when the planet gear is engaged with the outer gear ring in the lower grinding disc in the first state and in the second state, the rotation speed of the planet gear in the second state is obtained through the abrasion loss when the planet gear is engaged with the inner gear ring in the lower grinding disc in the first state and the abrasion loss when the planet gear is engaged with the outer gear ring in the lower grinding disc in the first state;

and determining the rotating speed of the inner gear ring in the second state and the rotating speed of the outer gear ring in the second state according to the autorotation rotating speed of the planet gear in the second state on the basis of the relationship among the rotating speeds and the tooth numbers of the planet gear, the inner gear ring and the outer gear ring.

3. The double side grinder of claim 2, wherein the inner ring gear turns in the second state in the same direction as the inner ring gear turns in the first state, and the outer ring gear turns in the second state in the same direction as the outer ring gear turns in the first state.

4. The double side grinder of claim 3, wherein the rotation speed of the outer ring gear in the first state is 12.5rad/s, the rotation speed of the inner ring gear in the first state is 0.5rad/s, the rotation speed of the outer ring gear in the second state is 0.5rad/s, and the rotation speed of the inner ring gear in the second state is 20.5 rad/s.

5. A double side grinder as claimed in any one of claims 1 to 4, characterised in that the first and second drive means each comprise a controller (21), a power source (22), a frequency converter (23), a three phase motor (24), a gearbox (25) and a gear (26); the frequency converter (23) is electrically connected with the controller (21), the power supply (22) and the three-phase motor (24) respectively, and the gearbox (25) is in transmission connection with the three-phase motor (24) and the gear (26) respectively; the gear (26) of the first driving device (16) is in transmission connection with the sun gear (14), and the gear (26) of the second driving device (17) is in transmission connection with the outer gear (15).

6. The double-sided lapping machine of any one of claims 1-4, further comprising a liquid supply system for providing an abrasive for lapping the sapphire substrate, wherein the abrasive comprises abrasive particles, a suspending agent and water, and the suspending agent is more than 4.41% by mass.

7. A double side grinder as claimed in claim 6, characterised in that the liquid supply system comprises a recovery tube (31), a recovery bucket (32), an agitator (33), a peristaltic pump (34), a feed tube (35) and a discharge tube (36); the first end of the discharge pipe (36) is arranged above the lower grinding disc (12), and the first end of the recovery pipe (31) is arranged below the lower grinding disc (12); the second end of recovery tube (31) the first end of inlet pipe (35) respectively with recycling bin (32) intercommunication, agitator (33) set up in recycling bin (32), the second end of inlet pipe (35) with the second end of discharging pipe (36) respectively with peristaltic pump (34) intercommunication.

8. A double-side polishing method, characterized by comprising:

providing a double-sided grinder, wherein the double-sided grinder comprises an upper grinding disc, a lower grinding disc, a planet wheel, a sun wheel, an outer gear, a first driving device and a second driving device; the upper grinding disc and the lower grinding disc are coaxial and are arranged oppositely, the sun gear is coaxially arranged between the upper grinding disc and the lower grinding disc, an inner gear ring is arranged at the edge of the sun gear, the outer gear is coaxially arranged at one side of the lower grinding disc, which is far away from the upper grinding disc, an outer gear ring is arranged at the edge of the outer gear, the planet gear is arranged on the surface of the lower grinding disc, which is opposite to the upper grinding disc, and is respectively meshed with the inner gear ring and the outer gear ring, the first driving device is in transmission connection with the sun gear, and the second driving device is in transmission connection with the outer gear;

placing a sapphire substrate in the planet wheel, and moving the upper grinding disc downwards to enable two end faces of the sapphire substrate to be respectively attached to the upper grinding disc and the lower grinding disc;

driving the upper grinding disc, the lower grinding disc, the sun gear and the outer gear to rotate, and grinding the sapphire substrate; the double-side lapping machine is alternately in a first state and a second state when lapping the sapphire substrate, the rotation speed of at least one of the first drive device and the second drive device in the first state is different from the rotation speed in the second state, and the total amount of wear in the lower lapping disc when the planet gears are meshed with the inner gear ring in the first state and in the second state is equal to the total amount of wear in the lower lapping disc when the planet gears are meshed with the outer gear ring in the first state and in the second state.

9. The double-side polishing method according to claim 8, further comprising:

determining the rotation speed of the planet gear in the first state, the rotation speed of the inner gear ring in the first state and the rotation speed of the outer gear ring in the first state based on process requirements;

obtaining the revolution rotating speed of the planet wheel in the first state according to the rotation rotating speed of the planet wheel in the first state based on the relation between the rotation rotating speed and the revolution rotating speed of the planet wheel;

determining the abrasion loss when the planetary gear in the lower grinding disc is meshed with the inner gear ring in the first state and the abrasion loss when the planetary gear in the lower grinding disc is meshed with the outer gear ring in the first state according to the rotation speed and the revolution speed of the planetary gear in the first state;

based on the relationship between the rotation speed and revolution speed of the planet gear, which is equal to the total abrasion loss when the planet gear is engaged with the inner gear ring in the lower grinding disc in the first state and in the second state, when the planet gear is engaged with the outer gear ring in the lower grinding disc in the first state and in the second state, the rotation speed of the planet gear in the second state is obtained through the abrasion loss when the planet gear is engaged with the inner gear ring in the lower grinding disc in the first state and the abrasion loss when the planet gear is engaged with the outer gear ring in the lower grinding disc in the first state;

and determining the rotating speed of the inner gear ring in the second state and the rotating speed of the outer gear ring in the second state according to the autorotation rotating speed of the planet gear in the second state on the basis of the relationship among the rotating speeds and the tooth numbers of the planet gear, the inner gear ring and the outer gear ring.

10. The double-sided lapping method of claim 9, wherein the inner ring gear turns in the first state in the same direction as the inner ring gear turns in the second state, and the outer ring gear turns in the first state in the same direction as the outer ring gear turns in the second state.

Technical Field

The invention relates to the technical field of grinding processes, in particular to a double-sided grinding machine and a double-sided grinding method.

Background

A Light Emitting Diode (LED) is a semiconductor electronic component capable of Emitting Light, and is widely used in the fields of indoor and outdoor lighting, automobile lighting, traffic lights, military equipment, and the like. Sapphire has good mechanical properties and physical properties, and is one of the main substrate materials for epitaxial growth of LEDs. In recent years, the prosperity of the LED application market drives the rapid development of the LED industry, the sapphire substrate market also develops good opportunities, and the demand for the yield of the sapphire substrate is higher and higher.

The manufacturing process of the sapphire substrate comprises the following steps: preparing a crystal rod composed of a single crystal material; cutting and polishing two ends of the crystal rod, rounding the side surface of the crystal rod, and processing the crystal rod into a regular cylinder, wherein the axial direction of the cylinder and the crystal direction of the crystal rod form a fixed included angle; and slicing, surface grinding and polishing and edge grinding are carried out on the cylinder to obtain the sapphire substrate. When the surface of the cylindrical slice is polished, compared with the original single-side processing technology (fixing the cylindrical slice on a ceramic disc, coating an abrasive material, pressing a grinding disc for polishing), the double-side grinding machine can simultaneously polish two end faces of the cylinder, so that the processing efficiency of the sapphire substrate is improved, and the yield requirement of the sapphire substrate is met.

The double-sided grinder comprises an upper grinding disc, a lower grinding disc, a planet wheel, a sun wheel and an outer gear. The upper grinding disc and the lower grinding disc are coaxially and oppositely arranged, the sun gear is coaxially arranged between the upper grinding disc and the lower grinding disc, the inner gear ring is arranged at the edge of the sun gear, the outer gear is coaxially arranged at one side of the lower grinding disc, which is far away from the upper grinding disc, the outer gear ring is arranged at the edge of the outer gear ring, and the planet gear is arranged on the surface of the lower grinding disc, which is opposite to the upper grinding disc, and is respectively meshed with the. The cylinder section is fixed in the planet wheel, and two terminal surfaces of cylinder paste with last mill and lower mill respectively. When the surface of the cylindrical slice is polished, the inner gear ring and the outer gear ring are driven to rotate, and the planet gear is driven to rotate; simultaneously, the upper grinding disc and the lower grinding disc are driven to rotate, and the planet wheel is driven to revolve.

In the process of implementing the invention, the inventor finds that the prior art has at least the following problems:

the grinding material can act on the cylinder slice, the upper grinding disc and the lower grinding disc simultaneously, and because the upper grinding disc is pressed on the lower grinding disc during grinding, the direction of the pressure is from the upper grinding disc to the lower grinding disc, the abrasion degree of the grinding material to the lower grinding disc is maximum, and the thickness of the lower grinding disc can change when the processing times are accumulated to a certain degree. And the cylinder section sets up on lower mill along the circumference of lower mill, and the linear velocity of cylinder section at inner ring gear department is different with the linear velocity of cylinder section at outer ring gear department for the degree of wear of cylinder section at inner ring gear department is different with the degree of wear of cylinder section at outer ring gear department, and the thickness variation condition of lower mill at outer ring gear department is different with the thickness variation condition of lower mill at outer ring gear department, leads to lower mill surface unevenness, influences the sliced machining precision of cylinder.

Disclosure of Invention

The embodiment of the invention provides a double-side grinding machine and a double-side grinding method, which can solve the problem that the machining precision of a cylindrical slice is influenced due to the fact that the surface of a lower grinding disc of the double-side grinding machine in the prior art is not flat. The technical scheme is as follows:

in one aspect, an embodiment of the present invention provides a double-side grinder, which includes an upper grinding disc, a lower grinding disc, a planetary gear, a sun gear, an outer gear, a first driving device, and a second driving device; the upper grinding disc and the lower grinding disc are coaxial and are arranged oppositely; the sun wheel is coaxially arranged between the upper grinding disc and the lower grinding disc, and an inner gear ring is arranged on the edge of the sun wheel; the outer gear is coaxially arranged on one side, away from the upper grinding disc, of the lower grinding disc, and an outer gear ring is arranged on the edge of the outer gear; the planet wheels are arranged on the surface of the lower grinding disc opposite to the upper grinding disc and are respectively meshed with the inner gear ring and the outer gear ring; the first driving device is in transmission connection with the sun gear, and the second driving device is in transmission connection with the external gear; the double-side lapping machine is alternately in a first state and a second state when lapping a sapphire substrate, the rotation speed of at least one of the first drive device and the second drive device in the first state is different from the rotation speed in the second state, and the total amount of wear in the lower lapping disc when the planet gears are meshed with the inner gear ring in the first state and in the second state is equal to the total amount of wear in the lower lapping disc when the planet gears are meshed with the outer gear ring in the first state and in the second state.

Optionally, the rotational speeds of the first and second driving devices in the first state and the second state are determined as follows:

determining the rotation speed of the planet gear in the first state, the rotation speed of the inner gear ring in the first state and the rotation speed of the outer gear ring in the first state based on process requirements;

obtaining the revolution rotating speed of the planet wheel in the first state according to the rotation rotating speed of the planet wheel in the first state based on the relation between the rotation rotating speed and the revolution rotating speed of the planet wheel;

determining the abrasion loss when the planetary gear in the lower grinding disc is meshed with the inner gear ring in the first state and the abrasion loss when the planetary gear in the lower grinding disc is meshed with the outer gear ring in the first state according to the rotation speed and the revolution speed of the planetary gear in the first state;

based on the relationship between the rotation speed and revolution speed of the planet gear, which is equal to the total abrasion loss when the planet gear is engaged with the inner gear ring in the lower grinding disc in the first state and in the second state, when the planet gear is engaged with the outer gear ring in the lower grinding disc in the first state and in the second state, the rotation speed of the planet gear in the second state is obtained through the abrasion loss when the planet gear is engaged with the inner gear ring in the lower grinding disc in the first state and the abrasion loss when the planet gear is engaged with the outer gear ring in the lower grinding disc in the first state;

and determining the rotating speed of the inner gear ring in the second state and the rotating speed of the outer gear ring in the second state according to the autorotation rotating speed of the planet gear in the second state on the basis of the relationship among the rotating speeds and the tooth numbers of the planet gear, the inner gear ring and the outer gear ring.

Further, the steering of the inner ring gear in the second state is the same as the steering of the inner ring gear in the first state, and the steering of the outer ring gear in the second state is the same as the steering of the outer ring gear in the first state.

Further, the rotating speed of the outer gear ring in the first state is 12.5rad/s, the rotating speed of the inner gear ring in the first state is 0.5rad/s, the rotating speed of the outer gear ring in the second state is 0.5rad/s, and the rotating speed of the inner gear ring in the second state is 20.5 rad/s. .

Optionally, the first driving device and the second driving device each include a controller, a power supply, a frequency converter, a three-phase motor, a gearbox, and a gear; the frequency converter is electrically connected with the controller, the power supply and the three-phase motor respectively, and the gearbox is in transmission connection with the three-phase motor and the gear respectively; the gear of the first driving device is in transmission connection with the sun gear, and the gear of the second driving device is in transmission connection with the external gear.

Optionally, the double-side grinder further comprises a liquid supply system, wherein the liquid supply system is used for supplying abrasive for grinding the sapphire substrate, the abrasive comprises grinding particles, a suspending agent and water, and the mass fraction of the suspending agent is more than 4.41%.

Further, the liquid supply system comprises a recovery pipe, a recovery barrel, a stirrer, a peristaltic pump, a feeding pipe and a discharging pipe; the first end of the discharge pipe is arranged above the lower grinding disc, and the first end of the recovery pipe is arranged below the lower grinding disc; the second end of recovery tube the first end of inlet pipe respectively with the recycling bin intercommunication, the agitator sets up in the recycling bin, the second end of inlet pipe with the second end of discharging pipe respectively with the peristaltic pump intercommunication.

In another aspect, an embodiment of the present invention provides a double-side polishing method, including:

providing a double-sided grinder, wherein the double-sided grinder comprises an upper grinding disc, a lower grinding disc, a planet wheel, a sun wheel, an outer gear, a first driving device and a second driving device; the upper grinding disc and the lower grinding disc are coaxial and are arranged oppositely, the sun gear is coaxially arranged between the upper grinding disc and the lower grinding disc, an inner gear ring is arranged at the edge of the sun gear, the outer gear is coaxially arranged at one side of the lower grinding disc, which is far away from the upper grinding disc, an outer gear ring is arranged at the edge of the outer gear, the planet gear is arranged on the surface of the lower grinding disc, which is opposite to the upper grinding disc, and is respectively meshed with the inner gear ring and the outer gear ring, the first driving device is in transmission connection with the sun gear, and the second driving device is in transmission connection with the outer gear;

placing a sapphire substrate in the planet wheel, and moving the upper grinding disc downwards to enable two end faces of the sapphire substrate to be respectively attached to the upper grinding disc and the lower grinding disc;

driving the upper grinding disc, the lower grinding disc, the sun gear and the outer gear to rotate, and grinding the sapphire substrate; the double-side lapping machine is alternately in a first state and a second state when lapping the sapphire substrate, the rotation speed of at least one of the first drive device and the second drive device in the first state is different from the rotation speed in the second state, and the total amount of wear in the lower lapping disc when the planet gears are meshed with the inner gear ring in the first state and in the second state is equal to the total amount of wear in the lower lapping disc when the planet gears are meshed with the outer gear ring in the first state and in the second state.

Optionally, the double-side grinding method further comprises:

determining the rotation speed of the planet gear in the first state, the rotation speed of the inner gear ring in the first state and the rotation speed of the outer gear ring in the first state based on process requirements;

obtaining the revolution rotating speed of the planet wheel in the first state according to the rotation rotating speed of the planet wheel in the first state based on the relation between the rotation rotating speed and the revolution rotating speed of the planet wheel;

determining the abrasion loss when the planetary gear in the lower grinding disc is meshed with the inner gear ring in the first state and the abrasion loss when the planetary gear in the lower grinding disc is meshed with the outer gear ring in the first state according to the rotation speed and the revolution speed of the planetary gear in the first state;

based on the relationship between the rotation speed and revolution speed of the planet gear, which is equal to the total abrasion loss when the planet gear is engaged with the inner gear ring in the lower grinding disc in the first state and in the second state, when the planet gear is engaged with the outer gear ring in the lower grinding disc in the first state and in the second state, the rotation speed of the planet gear in the second state is obtained through the abrasion loss when the planet gear is engaged with the inner gear ring in the lower grinding disc in the first state and the abrasion loss when the planet gear is engaged with the outer gear ring in the lower grinding disc in the first state;

and determining the rotating speed of the inner gear ring in the second state and the rotating speed of the outer gear ring in the second state according to the autorotation rotating speed of the planet gear in the second state on the basis of the relationship among the rotating speeds and the tooth numbers of the planet gear, the inner gear ring and the outer gear ring.

Further, the steering of the inner ring gear in the first state is the same as the steering of the inner ring gear in the second state, and the steering of the outer ring gear in the first state is the same as the steering of the outer ring gear in the second state.

The technical scheme provided by the embodiment of the invention has the following beneficial effects:

the rotation speeds of the inner gear ring and the outer gear ring can be respectively adjusted by respectively driving the sun gear and the outer gear to rotate by adopting different driving devices, so that the double-sided grinding machine is alternately in two states when the sapphire substrate is ground. The total abrasion loss is equal to the total abrasion loss when the meshing of the planet wheel and the inner gear ring is in two states in the lower grinding disc, and the abrasion loss of different areas of the lower grinding disc is balanced under the comprehensive action of the two states, so that the smoothness of the surface of the lower grinding disc is improved, and the processing precision of the sapphire substrate is improved.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

Fig. 1 is a schematic structural view of a double-side grinder according to an embodiment of the present invention;

fig. 2 is a schematic structural diagram of a driving device according to an embodiment of the present invention;

FIG. 3 is a schematic diagram of a liquid supply system provided by an embodiment of the invention;

fig. 4 is a flowchart of a double-side polishing method according to an embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

The embodiment of the invention provides a double-sided grinder. Fig. 1 is a schematic structural diagram of a double-side grinder according to an embodiment of the present invention. Referring to fig. 1, the double side grinder includes an upper grinding disc 11, a lower grinding disc 12, a planetary gear 13, a sun gear 14, an outer gear 15, a first driving device 16, and a second driving device 17. The upper grinding disc 11 and the lower grinding disc 12 are coaxial and are arranged oppositely; the sun gear 13 is coaxially arranged between the upper grinding disc 11 and the lower grinding disc 12, and the edge of the sun gear 13 is provided with an inner gear ring 18; the outer gear 15 is coaxially arranged on one side of the lower grinding disc 12 far away from the upper grinding disc 11, and an outer gear ring 19 is arranged on the edge of the outer gear 15; the planetary gears 13 are provided on the surface of the lower grinding disc 12 opposite to the upper grinding disc 11, and the planetary gears 13 are engaged with an inner ring gear 18 and an outer ring gear 19, respectively. The first drive device 16 is in driving connection with the sun gear 13, the second drive device 17 is in driving connection with the external gear 15, and the first drive device and the second drive device. The double side grinder alternately assumes a first state and a second state when grinding a sapphire substrate, the rotational speed of at least one of the first drive device 16 and the second drive device 17 in the first state is different from the rotational speed in the second state, and the total amount of wear of the lower turn table 12 at the meshing point a of the planetary gear 13 with the ring gear 18 in the first state and in the second state is equal to the total amount of wear of the lower turn table 12 at the meshing point B of the planetary gear 13 with the ring gear 19 in the first state and in the second state.

If S is adopted_{1 in}Shows the abrasion loss S of the lower millstone when the meshing of the planet wheel and the inner gear ring is in a first state_{2 in}Shows the abrasion loss S of the lower millstone when the planet wheel and the inner gear ring are engaged in a second state_{1 outer layer}Shows the abrasion loss S of the lower millstone when the planet wheel is engaged with the external gear ring in a first state_{2 outer layer}Indicating the amount of wear in the lower disc when the planet gear meshes with the outer ring gear in the second state, S in this embodiment_{1 in}+S_{2 in}＝S_{1 outer layer}+S_{2 outer layer}。

Because the abrasion of the lower grinding disc is caused by the rotation of the planet wheel and the revolution relative to the lower grinding disc, the abrasion quantity S of the lower grinding disc when the planet wheel is meshed with the inner gear ring and is in a first state_{1 in}＝[W_{1 self rotation}*r_Planet+(W_{Lower part}-W_{1 revolution of the sun})*r_{Inner part}]T; abrasion loss S of lower grinding disc when planetary wheel and inner gear ring are engaged in second state_{2 in}＝[W_{2 self rotation}*r_Planet+(W_{Lower part}-W_{2 revolution of the sun})*r_{Inner part}]T; abrasion loss S of lower grinding disc when planet wheel and outer gear ring are meshed in first state_{1 outer layer}＝[W_{1 self rotation}*r_Planet+(W_{Lower part}-W_{1 revolution of the sun})*r_{Outer cover}]T; abrasion loss S of lower grinding disc when planet wheel and outer gear ring are meshed in second state_{2 outer layer}＝[W_{2 self rotation}*r_Planet+(W_{Lower part}-W_{2 revolution of the sun})*r_{Outer cover}]T. Wherein, W_{1 self rotation}Is the rotation speed of the planet wheel in the first state, W_{2 self rotation}Is the rotation speed of the planet wheel in the second state, r_PlanetIs the radius of the planet wheel, W_{Lower part}Is the rotational speed of the lower grinding disc, W_{1 revolution of the sun}Is the revolution speed W of the planet wheel in the first state_{2 revolution of the sun}Is the revolution speed r of the planet wheel in the second state_{Inner part}Radius of the inner gear ring, r_{Outer cover}Is the radius of the outer gear ring.

According to the embodiment of the invention, different driving devices are adopted to respectively drive the sun gear and the outer gear to rotate, so that the rotating speeds of the inner gear ring and the outer gear ring can be respectively adjusted, and the double-sided grinding machine is alternately in two states when the sapphire substrate is ground. The total abrasion loss is equal to the total abrasion loss when the meshing of the planet wheel and the inner gear ring is in two states in the lower grinding disc, and the abrasion loss of different areas of the lower grinding disc is balanced under the comprehensive action of the two states, so that the smoothness of the surface of the lower grinding disc is improved, and the processing precision of the sapphire substrate is improved.

Alternatively, the rotational speeds of the first drive device 16 and the second drive device in the first state and the rotational speed in the second state may be determined as follows:

firstly, determining the rotation speed of a planet wheel in a first state, the rotation speed of an inner gear ring in the first state and the rotation speed of an outer gear ring in the first state based on process requirements;

secondly, obtaining the revolution speed of the planet wheel in the first state according to the rotation speed of the planet wheel in the first state based on the relation between the rotation speed and the revolution speed of the planet wheel;

thirdly, determining the abrasion loss of the lower grinding disc when the meshing of the planet wheel and the inner gear ring is in the first state and the abrasion loss of the lower grinding disc when the meshing of the planet wheel and the outer gear ring is in the first state according to the rotation speed and the revolution speed of the planet wheel in the first state;

fourthly, based on the total abrasion loss when the planet wheel in the lower grinding disc is meshed with the inner gear ring in the first state and in the second state, the total abrasion loss is equal to the total abrasion loss when the planet wheel in the lower grinding disc is meshed with the outer gear ring in the first state and in the second state, and the relationship between the rotation speed and the revolution speed of the planet wheel, the rotation speed of the planet wheel in the second state is obtained through the abrasion loss when the planet wheel in the lower grinding disc is meshed with the inner gear ring in the first state and the abrasion loss when the planet wheel in the lower grinding disc is meshed with the outer gear ring in the first state;

and fifthly, determining the rotating speed of the inner gear ring in the second state and the rotating speed of the outer gear ring in the second state according to the autorotation rotating speed of the planet gear in the second state based on the relationship among the rotating speeds and the number of teeth of the planet gear, the inner gear ring and the outer gear ring.

In this embodiment, the rotation speed of the ring gear is the rotation speed of the sun gear, and since the sun gear is driven by the first driving device, the rotation speed of the first driving device can be obtained after the rotation speed of the ring gear is determined. Similarly, the rotation speed of the external ring gear is the rotation speed of the external gear, and since the external gear is driven by the second driving device, the rotation speed of the second driving device can be obtained after the rotation speed of the external ring gear is determined.

In practical applications, the above steps finally result in the relationship between the rotation speed of the ring gear in the second state and the rotation speed of the ring gear in the second state. From this relationship, the rotation speeds of the plurality of pairs of inner ring gears and outer ring gears can be obtained. And based on actual conditions, selecting one pair of the rotation speeds as the rotation speed of the inner gear ring in the second state and the rotation speed of the outer gear ring in the second state.

Firstly, based on the process requirements, the rotating speeds of the planet wheel, the inner gear ring and the outer gear ring in the first state are determined, so that the planet wheel can run in the optimal state in a part of time period, and the optimal processing effect is achieved. Meanwhile, the rotating speed of the planet wheel in the first state is used as a known quantity, the rotating speed of the planet wheel in the second state is calculated, the calculated quantity can be reduced, and the implementation is convenient.

In practical application, according to a gear ratio formula, the relationship between the rotation speed and the revolution speed of the planet wheel can be obtained as follows: w_{Revolution of the sun}/W_{Self-rotation}＝N_Planet/N_{Inner part}. Since the revolution rotation speed of the planetary gear in the first state may be different from the revolution rotation speed in the second state, and the rotation speed in the first state may be different from the rotation speed in the second state, the relationship between the rotation speed and the revolution rotation speed of the planetary gear in the first state is: w_{1 revolution of the sun}/W_{1 self rotation}＝N_Planet/N_{Inner part}(ii) a The relationship between the rotation speed and the revolution speed of the planet wheel in the second state is as follows: w_{2 revolution of the sun}/W_{2 self rotation}＝N_Planet/N_{Inner part}. Wherein, W_{Revolution of the sun}Is the revolution speed of the planet wheel, W_{1 revolution of the sun}Is the revolution speed W of the planet wheel in the first state_{2 revolution of the sun}The revolution speed of the planet wheel in the second state is obtained; w_{Self-rotation}Is the rotation speed of the planet wheel, W_{1 self rotation}Is the rotation speed of the planet wheel in the first state, W_{2 self rotation}The rotation speed of the planet wheel in the second state is the rotation speed of the planet wheel; n is a radical of_PlanetIs the number of teeth of the planet wheel, N_{Inner part}The number of teeth of the inner gear ring.

In addition, according to a gear ratio formula, the relationship between the rotating speed and the number of teeth of the planet gear, the inner gear ring and the outer gear ring can be obtained as follows: (W)_{Outer cover}-W_{Inner part})/W_{Self-rotation}＝(N_{Outer cover}-N_{Inner part})/N_Planet. Since the rotation speed of the outer ring gear in the first state may be different from the rotation speed in the second state, the rotation speed of the inner ring gear in the first state may be different from the rotation speed in the second state, and the rotation speed in the first state may be different from the rotation speed in the second state, the relationship between the rotation speed and the number of teeth of the planetary gear, the inner ring gear, and the outer ring gear in the first state is: (W)_{1 outer layer}-W_{1 in})/W_{1 self rotation}＝(N_{Outer cover}-N_{Inner part})/N_Planet(ii) a The relationship between the rotation speed and the revolution speed of the planet wheel in the second state is as follows: (W)_{2 outer layer}-W_{2 in})/W_{2 self rotation}＝(N_{Outer cover}-N_{Inner part})/N_Planet. Wherein, W_{Outer cover}Is the rotational speed of the outer ring gear, W_{1 outer layer}Is the rotational speed of the external gear ring in the first state, W_{2 outer layer}The rotating speed of the outer gear ring in the second state; w_{Inner part}Is the rotational speed of the inner gear ring, W_{1 in}Is the rotational speed of the inner gear ring in the first state, W_{2 in}The rotating speed of the inner gear ring in the second state is obtained; w_{Self-rotation}Is the rotation speed of the planet wheel, W_{1 self rotation}Is the rotation speed of the planet wheel in the first state, W_{2 self rotation}The rotation speed of the planet wheel in the second state is the rotation speed of the planet wheel; n is a radical of_{Outer cover}Number of teeth of outer toothed ring, N_{Inner part}Number of teeth of inner gear ring, N_PlanetThe number of teeth of the planet wheel.

Further, the rotation direction of the inner ring gear in the second state may be the same as the rotation direction of the inner ring gear in the first state, and the rotation direction of the outer ring gear in the second state may be the same as the rotation direction of the outer ring gear in the first state. The inner gear ring and the outer gear ring keep the same steering rotation, so that the influence on the stability of the internal connection of the driving device and even the grinding process of the sapphire substrate due to the steering change can be avoided.

For example, the rotational speed of the outer ring gear in the first state may be 12.5rad/s and the rotational speed of the inner ring gear in the first state may be 0.5 rad/s; the rotation speed of the outer ring gear in the second state can be 0.5rad/s, and the rotation speed of the inner ring gear in the second state can be 20.5 rad/s. The grinding disc grinding machine can not only match the process requirements to achieve the best processing effect, but also balance the abrasion loss of each area of the lower grinding disc and improve the flatness of the lower grinding disc.

In practical application, the number of teeth of the outer gear ring may be 200, the number of teeth of the planet gear may be 71, the number of teeth of the inner gear ring may be 58, the radius of the inner gear ring may be 225mm, and the radius of the outer gear ring may be 640 mm. The radius of the planet wheel can be 237.5mm, the rotating speed of the lower grinding disc can be 11rad/s, and the rotating speed of the planet wheel in the first state can be 6 rad/s. By processing the sapphire substrate according to the parameters, a better processing effect can be obtained.

Fig. 2 is a schematic structural diagram of a driving device according to an embodiment of the present invention. Referring to fig. 2, optionally, the first drive and the second drive may each include a controller 21, a power source 22, a frequency converter 23, a three-phase motor 24, a gearbox 25 and a gear 26. The frequency converter 23 is respectively electrically connected with the controller 21, the power supply 22 and the three-phase motor 24, and the gearbox 25 is respectively in transmission connection with the three-phase motor 24 and the gear 26; the gear 26 of the first drive is in driving connection with the sun gear 14, and the gear 26 of the second drive is in driving connection with the external gear 15.

The rotating speed of the three-phase motor is set through the controller, the frequency of a power supply signal is changed through the frequency converter, the rotating speed of the three-phase motor is controlled, and then the inner gear ring or the outer gear ring is driven to rotate at the required speed through the gearbox and the gear, so that the method is simple and convenient to achieve.

Optionally, the double-sided grinder can further comprise a liquid supply system, wherein the liquid supply system is used for supplying abrasive for grinding the sapphire substrate, the abrasive comprises grinding particles, a suspending agent and water, and the mass fraction of the suspending agent is more than 4.41%. By adding the suspending agent with the mass fraction of more than 4.41 percent into the grinding material, the uniform distribution of the grinding particles is ensured, so that the mass fraction of the grinding particles is greatly reduced, the use amount of the grinding particles is greatly reduced, and the realization cost is reduced. And the distribution of the grinding particles is more uniform, and the grinding effect of the sapphire substrate is better.

Further, the ratio of the mass fractions of the suspending agent, the abrasive particles and the water may be 0.15:1: 2.25. By adopting the proportion, the grinding wheel can be matched with the rotating speed of the planet wheel, a good grinding effect is achieved, the use of materials can be reduced, and the realization effect and the realization cost can be better considered.

FIG. 3 is a schematic structural diagram of a liquid supply system according to an embodiment of the invention. Referring to fig. 3, optionally, the liquid supply system may include a recovery tube 31, a recovery drum 32, an agitator 33, a peristaltic pump 34, a feed tube 35, and a discharge tube 36. The first end of the discharge pipe 36 is arranged above the lower grinding disc 12, and the first end of the recovery pipe 31 is arranged below the lower grinding disc 12; the second end of the recycling pipe 31 and the first end of the feeding pipe 35 are respectively communicated with the recycling bin 32, the stirrer 33 is arranged in the recycling bin 32, and the second end of the feeding pipe 35 and the second end of the discharging pipe 36 are respectively communicated with the peristaltic pump 34.

The stirrer is additionally arranged to enhance the flowability of the grinding materials, so that the grinding materials can be transported by the peristaltic pump, the supply amount of the grinding materials can be controlled more accurately by transporting the grinding materials by the peristaltic pump, the use amount of the grinding materials is further reduced, and the implementation cost is reduced.

The embodiment of the invention provides a double-side grinding method which is suitable for a double-side grinding machine shown in figure 1. Fig. 4 is a flowchart of a double-side polishing method according to an embodiment of the present invention. Referring to fig. 4, the double-side grinding method includes:

step 201: a double side grinder is provided.

In the present embodiment, the double side grinder includes an upper grinding disc, a lower grinding disc, a planetary gear, a sun gear, an external gear, a first drive device, and a second drive device. The upper grinding disc and the lower grinding disc are coaxial and are arranged oppositely, the sun wheel is coaxially arranged between the upper grinding disc and the lower grinding disc, and an inner gear ring is arranged at the edge of the sun wheel; the outer gear is coaxially arranged on one side of the lower grinding disc, which is far away from the upper grinding disc, and an outer gear ring is arranged on the edge of the outer gear; the planet wheel is arranged on the surface of the lower grinding disc opposite to the upper grinding disc and is respectively meshed with the inner gear ring and the outer gear ring; the first driving device is in transmission connection with the sun gear, and the second driving device is in transmission connection with the external gear.

Step 202: and placing the sapphire substrate in the planetary wheel, and moving the upper grinding disc downwards to ensure that two end faces of the sapphire substrate are respectively attached to the upper grinding disc and the lower grinding disc.

Step 203: and the upper grinding disc, the lower grinding disc, the sun gear and the outer gear are driven to rotate, and the sapphire substrate is ground.

In this embodiment, the double-side grinder alternately assumes a first state and a second state when grinding the sapphire substrate, the rotational speed of at least one of the first drive device and the second drive device in the first state is different from the rotational speed in the second state, and the total amount of wear in the lower turn table when the planetary gear meshes with the ring gear in the first state and in the second state is equal to the total amount of wear in the lower turn table when the planetary gear meshes with the ring gear in the first state and in the second state.

Optionally, the double-side grinding method may further include:

determining the rotation speed of the planet gear in the first state, the rotation speed of the inner gear ring in the first state and the rotation speed of the outer gear ring in the first state based on process requirements;

obtaining the revolution rotating speed of the planet wheel in the first state according to the rotation rotating speed of the planet wheel in the first state based on the relation between the rotation rotating speed and the revolution rotating speed of the planet wheel;

determining the abrasion loss when the meshing of the planet wheel and the inner gear ring in the lower grinding disc is in the first state and the abrasion loss when the meshing of the planet wheel and the outer gear ring in the lower grinding disc is in the first state according to the rotation speed and the revolution speed of the planet wheel in the first state;

based on the relationship between the total abrasion loss when the planet wheel in the lower grinding disc is meshed with the inner gear ring in the first state and the total abrasion loss when the planet wheel in the lower grinding disc is meshed with the outer gear ring in the second state, and the rotation speed of the planet wheel in the second state, the rotation speed of the planet wheel is obtained through the abrasion loss when the planet wheel in the lower grinding disc is meshed with the inner gear ring in the first state and the abrasion loss when the planet wheel in the lower grinding disc is meshed with the outer gear ring in the first state;

and determining the rotating speed of the inner gear ring in the second state and the rotating speed of the outer gear ring in the second state according to the autorotation rotating speed of the planet gears in the second state on the basis of the relationship among the rotating speeds and the tooth numbers of the planet gears, the inner gear ring and the outer gear ring.

Firstly, based on the process requirements, the rotating speeds of the planet wheel, the inner gear ring and the outer gear ring in the first state are determined, so that the planet wheel can run in the optimal state in a part of time period, and the optimal processing effect is achieved. Meanwhile, the rotating speed of the planet wheel in the first state is used as a known quantity, the rotating speed of the planet wheel in the second state is calculated, the calculated quantity can be reduced, and the implementation is convenient.

Further, the rotation direction of the inner ring gear in the second state may be the same as the rotation direction of the inner ring gear in the first state, and the rotation direction of the outer ring gear in the second state may be the same as the rotation direction of the outer ring gear in the first state. The inner gear ring and the outer gear ring keep the same steering rotation, so that the influence on the stability of the internal connection of the driving device and even the grinding process of the sapphire substrate due to the steering change can be avoided.

For example, the rotational speed of the outer ring gear in the first state may be 12.5rad/s and the rotational speed of the inner ring gear in the first state may be 0.5 rad/s; the rotation speed of the outer ring gear in the second state can be 0.5rad/s, and the rotation speed of the inner ring gear in the second state can be 20.5 rad/s. The grinding disc grinding machine can not only match the process requirements to achieve the best processing effect, but also balance the abrasion loss of each area of the lower grinding disc and improve the flatness of the lower grinding disc.

In practical application, the number of teeth of the outer gear ring may be 200, the number of teeth of the planet gear may be 71, the number of teeth of the inner gear ring may be 58, the radius of the inner gear ring may be 225mm, and the radius of the outer gear ring may be 640 mm. The radius of the planet wheel can be 237.5mm, the rotating speed of the lower grinding disc can be 11rad/s, and the rotating speed of the planet wheel in the first state can be 6 rad/s. By processing the sapphire substrate according to the parameters, a better processing effect can be obtained.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.