Air-suspended precision wafer dicing motorized spindle

Abstract

The application discloses an air-suspended precision wafer cutting electric spindle, wherein an air-floatation gap between an outer wall of a mandrel and an inner wall of an air inlet bearing is communicated with an external air source device. A first end of the mandrel is coaxially fixed with a motor rotor, and the motor rotor is located at an inner side of a motor stator. A plurality of iron core protruding portions on an inner peripheral wall of the motor stator are each provided with a coil electrically connected with a control end of an external machine table. The motor rotor comprises a plurality of permanent magnets fixed on an outer peripheral wall of the mandrel. A water jacket is coaxially arranged in a cylinder barrel, and a cooling water channel is arranged on an outer wall of the water jacket and close to the motor stator, and the cooling water channel is connected with an external circulating water supply device. The permanent magnets of the motor rotor are fixed on the outer wall of the mandrel in a patch type structure, and in the case of equal power output, the motor structure has smaller high-order harmonics and more stable output power. The motor stator is fixed on the inner wall of the water jacket, so that water-cooling rapid heat dissipation of the motor can be realized, and the operation precision of the motor is improved.

Description

Technical Field

[0001] This invention relates to the technical field of wafer dicing spindles, and particularly to an air-suspended precision wafer dicing electric spindle. Background Technology

[0002] When processing semiconductors such as wafers, the requirements for processing precision are extremely high, which places very high demands on the electric spindles manufactured by the manufacturers. Existing electric spindles used for wafer dicing generally employ air-bearing spindles. In these spindles, an air film fills the space between the spindle and the inner wall of the cylinder, significantly reducing friction and ensuring processing precision to a certain extent. However, the motors in these air-bearing electric spindles use traditional toroidal motors or magnetic strip motors. The motor coils are wound around the rotor, which is fixed to the spindle, while the permanent magnet acts as the stator, fixed to the inner wall of the cylinder. This traditional motor structure generates significant high-order harmonics during operation, affecting the motor's output power. Furthermore, because the coils are wound around the rotor, which is not in direct contact with the inner wall of the cylinder, the heat generated during rotor operation accumulates inside the motor and is difficult to dissipate, also affecting the motor's operational precision. Summary of the Invention

[0003] To address the problems existing in the prior art, the present invention provides an air-suspended precision wafer dicing electric spindle.

[0004] To achieve the above objectives, the present invention proposes an air-suspended precision wafer dicing electric spindle, comprising: a cylinder, an intake bearing and a motor stator fixed inside the cylinder, a spindle rotatably mounted inside the intake bearing, an air-float gap between the outer wall of the spindle and the inner wall of the intake bearing, an air guide hole communicating with the air-float gap on the outer wall of the intake bearing, and a first air passage communicating with the air guide hole inside the cylinder, the first air passage being connected to an external air source device. A motor rotor is coaxially fixed to the first end of the spindle, the motor rotor being located inside the motor stator, and the second end of the spindle extending out of the cylinder and connected to the dicing tool. A plurality of iron core protrusions are evenly distributed on the inner peripheral wall of the motor stator, and coils are wound on the iron core protrusions, the coils being electrically connected to the control terminal of an external machine tool. The motor rotor includes permanent magnets corresponding one-to-one with the plurality of iron core protrusions, the plurality of permanent magnets being fixed on the outer peripheral wall of the first end of the spindle. A water jacket is coaxially installed inside the cylinder, with its outer wall sealing against the inner wall of the cylinder. The outer wall of the stator is also tightly fitted against the inner wall of the water jacket. Cooling water channels are located on the outer wall of the water jacket near the motor stator. The cylinder interior has inlet and outlet water channels that connect to the two ends of the cooling water channels, respectively. These water channels and outlet water channels are connected to an external circulating water supply device.

[0005] Preferably, a rear seat is fixed to the end of the cylinder barrel away from the cutting tool, and a sensor is fixed on the rear seat. One end of the sensor is electrically connected to the control terminal of the external machine tool, and the other end of the sensor is connected to the spindle.

[0006] Preferably, the sensor includes: a carbon brush aluminum sleeve fixed on the rear seat, the carbon brush aluminum sleeve extending into the cylinder, and the carbon brush aluminum sleeve being electrically connected to the control terminal of an external machine tool. A carbon rod is inserted into the carbon brush aluminum sleeve, a holding spring is provided inside the carbon brush aluminum sleeve, and a copper block is embedded on the spindle. The holding spring presses the carbon rod against the copper block, and the copper block is electrically connected to the dicing tool.

[0007] Preferably, the outer wall of the water jacket is provided with two sealing grooves, the cooling water channel is located on the outer wall between the two sealing grooves, and a sealing ring is provided in the sealing groove to fit tightly against the inner wall of the cylinder. The inner wall of the water jacket is provided with a positioning groove, and the motor stator is bonded and fixed to the inner wall of the positioning groove.

[0008] Preferably, the cooling water channel is spiral-shaped around the outer wall of the water jacket.

[0009] Preferably, the cylinder is fitted with a shaft lock arranged radially along the spindle. The shaft lock has an air inlet. The cylinder is provided with a second air passage that connects the air inlet to an external air source device. The shaft lock can contact the outer wall of the spindle under air pressure and lock the spindle in place.

[0010] Preferably, the shaft lock includes: a shaft lock outer sleeve, a shaft lock pin, a shaft lock spring, and a shaft lock plug. Both the shaft lock outer sleeve and the shaft lock plug are embedded inside the cylinder. The shaft lock outer sleeve has openings at both ends, and the shaft lock plug is fixed to the end of the shaft lock outer sleeve away from the spindle. The shaft lock pin is placed inside the shaft lock outer sleeve, and the shaft lock spring is sleeved on the shaft lock pin. One end of the shaft lock spring presses against the shaft lock pin, and the other end of the shaft lock spring presses against the inner wall of the shaft lock outer sleeve. An air inlet is formed on the shaft lock outer sleeve, and the gap between the air inlet and the shaft lock pin and the shaft lock plug is open.

[0011] Preferably, the outer peripheral wall of the shaft lock sleeve is provided with an air guide groove, and an air inlet is opened at the bottom of the air guide groove, with at least one air inlet provided.

[0012] Preferably, the outer wall of the cylinder has an installation plane parallel to the axis of the spindle, and an installation block is fixed on the outer wall of the cylinder. The installation block has a lifting plane parallel to the installation plane, and several threaded connection holes are reserved on the lifting plane.

[0013] Compared with existing technologies, the advantages of this invention are as follows: This electric spindle structure employs a coil wound around the motor stator, with the coil directly connected to external AC power to generate a magnetic field that changes magnetic poles. The permanent magnets of the motor rotor are fixed to the outer wall of the spindle using a patch structure. Under the same power output, this motor structure exhibits lower high-order harmonics and more stable output power. Furthermore, since the coil is directly wound around the motor stator, which is fixed to the inner wall of the water jacket, rapid water cooling of the motor can be achieved, improving the motor's operational accuracy. Attached Figure Description

[0014] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0015] Figure 1 This is an overall structural diagram of an embodiment of the present invention;

[0016] Figure 2 This is a cross-sectional structural diagram of an embodiment of the present invention;

[0017] Figure 3 This is another cross-sectional structural diagram of an embodiment of the present invention;

[0018] Figure 4 This is a diagram showing the installation structure of the motor and spindle in one embodiment of the present invention;

[0019] Figure 5 This is a structural diagram of the water jacket in one embodiment of the present invention;

[0020] Figure 6 for Figure 3 A magnified view of a section at point A in the middle;

[0021] Figure 7 This is another overall structural diagram of an embodiment of the present invention;

[0022] The objectives, features, and advantages of this invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0023] This invention proposes an air-suspended precision wafer dicing electric spindle.

[0024] Reference Figure 1-7 , Figure 1 This is an overall structural diagram of an embodiment of the present invention. Figure 2 This is a cross-sectional structural diagram of an embodiment of the present invention. Figure 3 This is another cross-sectional structural diagram of an embodiment of the present invention. Figure 4 This is a diagram showing the installation structure of the motor and spindle in one embodiment of the present invention. Figure 5 This is a structural diagram of the water jacket in one embodiment of the present invention. Figure 6 for Figure 3 A magnified view of a portion of point A in the middle. Figure 7 This is another overall structural diagram of an embodiment of the present invention.

[0025] like Figure 1-3As shown in this embodiment of the invention, the air-suspended precision wafer dicing spindle includes: a cylinder 1, an intake bearing 2 and a motor stator 3 fixed inside the cylinder 1, a spindle 4 rotatably mounted inside the intake bearing 2, an air-float gap between the outer wall of the spindle 4 and the inner wall of the intake bearing 2, and an air guide hole (not shown in the figure) communicating with the air-float gap on the outer wall of the intake bearing 2. A first air passage 6 communicating with the air guide hole is provided inside the cylinder 1, and the first air passage 6 is connected to an external air source device. The external air source device injects high-pressure gas into the air-float gap through the first air passage 6 and the air guide hole 5, forming an air film between the outer wall of the spindle 4 and the inner wall of the intake bearing 2, greatly reducing the wear of the spindle 4.

[0026] like Figure 2-4 As shown, a motor rotor is coaxially fixed to the first end of the mandrel 4, which is located inside the motor stator 3. The second end of the mandrel 4 extends out of the cylinder 1 and is fixedly connected to the dicing tool. Several iron core protrusions 7 are evenly distributed on the inner circumferential wall of the motor stator 3, and coils (not shown in the figure) are wound on the iron core protrusions 7. The coils are electrically connected to the control terminal of the external machine tool. The motor rotor includes permanent magnets 8 corresponding one-to-one with the iron core protrusions 7, and the permanent magnets 8 are fixed to the outer circumferential wall of the first end of the mandrel 4. During operation, the control terminal of the external machine tool provides alternating current to the coils, causing the iron core protrusions 7 to be magnetized and their magnetic poles to change periodically. This, in turn, drives the motor rotor to rotate through the magnetic force of the permanent magnets 8, which in turn drives the mandrel 4 to rotate, thereby causing the dicing tool mounted on the second end of the mandrel 4 to move.

[0027] like Figure 1 As shown, a rear seat 9 is fixed to the end of the cylinder 1 furthest from the dicing tool. A sensor is fixed on the rear seat 9. One end of the sensor is electrically connected to the control terminal of the external machine tool, and the other end of the sensor is connected to the mandrel 4. During operation, when the dicing tool touches the wafer to be processed, the sensor sends a sensing signal to the control terminal of the external machine tool, which then controls the motor to start working.

[0028] like Figure 2-3As shown, the sensor includes: a carbon brush aluminum sleeve 10 fixed on the rear seat 9, the carbon brush aluminum sleeve 10 extending into the cylinder 1, and the carbon brush aluminum sleeve 10 electrically connected to the control terminal of the external machine tool. A carbon rod 11 is inserted into the carbon brush aluminum sleeve 10, a retaining spring 5 is provided inside the carbon brush aluminum sleeve 10, and a copper block 12 is embedded on the spindle 4. The retaining spring 5 presses the carbon rod 11 against the copper block 12, and the copper block 12 is electrically connected to the dicing tool. When the dicing tool contacts the wafer to be processed, an electrical circuit is formed between the wafer, the dicing tool, the copper block 12, the carbon rod 11, the carbon brush aluminum sleeve 10, and the control terminal of the machine tool. The control terminal of the machine tool controls the motor to start working according to the electrical signal of this circuit. This sensor, using a carbon brush aluminum sleeve 10 and using friction contact between the carbon rod 11 and the copper block 12, is very durable, has a low failure rate, and high signal detection accuracy. Of course, in other embodiments of this example, other existing sensors can also be used.

[0029] like Figure 3 and Figure 5 As shown, a water jacket 13 is coaxially mounted inside the cylinder 1. The outer wall of the water jacket 13 is sealed to the inner wall of the cylinder 1, and the outer wall of the motor stator 3 is tightly fitted to the inner wall of the water jacket 13. A cooling water channel 14 is provided on the outer wall of the water jacket 13 near the motor stator 3. An inlet channel (not shown) and an outlet channel (not shown) are respectively connected to both ends of the cooling water channel 14. The inlet and outlet channels are connected to an external circulating water supply device via an inlet nozzle 15 and an outlet nozzle (not shown), respectively. By installing the water jacket 13, rapid water cooling of the motor can be achieved, improving the motor's operating accuracy.

[0030] like Figure 5 As shown, the outer wall of the water jacket 13 is provided with two sealing grooves 17, and the cooling water channel 14 is located on the outer wall between the two sealing grooves 17. A sealing ring is provided inside the sealing groove 17 to tightly fit the inner wall of the cylinder 1, ensuring the sealing performance of the water jacket 13. The inner wall of the water jacket 13 is provided with a positioning groove, and the motor stator 3 is bonded and fixed to the inner wall of the positioning groove, making the installation of the motor stator 3 more convenient. The cooling water channel 14 is spirally arranged around the outer wall of the water jacket 13 to dissipate heat from the entire outer periphery of the motor stator 3, improving heat dissipation efficiency.

[0031] A shaft lock 18 is embedded within the cylinder 1, arranged radially along the spindle 4. The shaft lock 18 has an air inlet. The cylinder 1 has a second air passage 19 connecting the air inlet to an external air source device. Under air pressure, the shaft lock 18 can contact the outer wall of the spindle 4 and lock the spindle 4 in place. By setting the shaft lock 18, rapid braking of the spindle 4 can be achieved, ensuring the safe operation of the electric spindle. Moreover, the shaft lock 18 is pneumatic and shares the same external air source device with the air intake bearing 2, making the structural design simpler and the cost lower.

[0032] like Figure 6As shown, the shaft lock 18 includes: a shaft lock outer sleeve 20, a shaft lock pin 21, a shaft lock spring 22, and a shaft lock plug 23. Both the shaft lock outer sleeve 20 and the shaft lock plug 23 are embedded inside the cylinder 1. The shaft lock outer sleeve 20 has openings at both ends, and the shaft lock plug 23 is fixed to the end of the shaft lock outer sleeve 20 away from the spindle 4. The shaft lock pin 21 is placed inside the shaft lock outer sleeve 20, and the shaft lock spring 22 is sleeved on the shaft lock pin 21. One end of the shaft lock spring 22 presses against the shaft lock pin 21, and the other end of the shaft lock spring 22 presses against the inner wall of the shaft lock outer sleeve 20. An air inlet is opened on the shaft lock outer sleeve 20, and the gap between the air inlet and the shaft lock pin 21 and the shaft lock plug 23 is connected. The shaft lock 18 has a simple overall structure, is easy to manufacture, and is very easy to assemble.

[0033] The outer peripheral wall of the shaft lock sleeve 20 is provided with an air guide groove 24, and an air inlet is opened at the bottom of the air guide groove 24. At least one air inlet is provided. With this air guide groove 24, the assembly precision requirement of the shaft lock 18 is not very high. It is not necessary for the air inlet to be completely aligned with the outlet of the second air passage 19. It is only necessary for the outlet of the second air passage 19 to be connected to the air guide groove 24.

[0034] like Figure 7 As shown, a mounting plane 25 parallel to the axis of the spindle 4 is provided on the outer wall of the cylinder 1. This mounting plane 25 allows the electric spindle to be clamped and mounted onto the machine tool. Figure 1 As shown, a mounting block 26 is also fixed on the outer wall of the cylinder 1. The mounting block 26 has a lifting plane 27 parallel to the mounting plane 25, and several threaded connection holes are reserved on the lifting plane 27. By setting the mounting block 26 and the lifting plane 27, the electric spindle can be hoisted onto the machine tool. Two installation methods are provided, making it more flexible and convenient to use.

[0035] Compared with the prior art, the advantages of this invention are as follows: The electric spindle structure employs a coil wound around the motor stator 3, with the coil directly connected to external AC power to generate a magnetic field with changing poles. The permanent magnet 8 of the motor rotor is fixed to the outer wall of the spindle 4 using a patch structure. Under the same power output, this motor structure exhibits lower high-order harmonics and more stable output power. Furthermore, since the coil is directly wound around the motor stator 3, and the motor stator 3 is fixed to the inner wall of the water jacket 13, rapid water cooling of the motor can be achieved, improving the motor's operational accuracy.

[0036] The above description is merely a preferred embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural transformations made using the contents of the present invention's specification and drawings under the inventive concept of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. An air-suspended precision wafer dicing motorized spindle, characterized by, The utility model provides a kind of cylinder-piston type cutting machine, including: Cylinder, air inlet bearing and motor stator are fixed in the cylinder, the mandrel is rotationally arranged in the air inlet bearing, air float gap is arranged between the outer wall of the mandrel and the inner wall of the air inlet bearing, the outer wall of the air inlet bearing is equipped with the air guide hole being communicated with the air float gap, the inside of the cylinder is equipped with the first air channel being communicated with the air guide hole, and the first air channel is communicated with the gas source device outside;The first end of the mandrel is coaxially fixed with motor rotor, the motor rotor is located in the inside of the motor stator, the second end of the mandrel is stretched out of the cylinder and is connected with cutting tool;The inner peripheral wall of the motor stator is uniformly distributed with a plurality of core protrusions, the coil is wound on the core protrusion, and the coil is electrically connected with the control end of the external machine table;The motor rotor includes a plurality of permanent magnets corresponding to the core protrusions, and the plurality of permanent magnets are fixed on the outer peripheral wall of the first end of the mandrel;Water jacket is coaxially arranged in the cylinder, the outer wall of the water jacket is sealingly attached to the inner wall of the cylinder, and the outer wall of the motor stator is closely attached to the inner wall of the water jacket;The outer wall of the water jacket is provided with a cooling water channel near the motor stator, and the inside of the cylinder is provided with a water inlet channel and a water outlet channel communicated with both ends of the cooling water channel respectively, and the water inlet channel and the water outlet channel are connected with the circulating water supply device outside.

2. The air levitated precision wafer dicing electrospindle according to claim 1, wherein, The end of the cylinder away from the cutting tool is fixed with a rear seat, the inductor is fixed on the rear seat, one end of the inductor is electrically connected with the control end of the external machine table, and the other end of the inductor is connected with the mandrel.

3. The air levitated precision wafer dicing electrospindle according to claim 2, wherein, The inductor includes: a carbon brush aluminum sleeve fixed on the rear seat, the carbon brush aluminum sleeve extends into the cylinder, and the carbon brush aluminum sleeve is electrically connected with the control end of the external machine table;The carbon rod is inserted into the carbon brush aluminum sleeve, the carbon brush aluminum sleeve is provided with a supporting spring, the copper block is embedded on the mandrel, the carbon rod is abutted on the copper block by the supporting spring, and the copper block is electrically connected with the cutting tool.

4. The air levitated precision wafer dicing electrospindle according to claim 1, wherein, The outer wall of the water jacket is provided with two sealing grooves, the cooling water channel is arranged on the outer wall between the two sealing grooves, and the sealing ring is arranged in the sealing groove and closely attached to the inner wall of the cylinder;The inner wall of the water jacket is provided with a positioning groove, and the motor stator is adhesively fixed on the inner wall of the positioning groove.

5. The air levitated precision wafer dicing electrospindle according to claim 1, wherein, The cooling water channel spirally surrounds the outer wall of the water jacket.

6. The air levitated precision wafer dicing electrospindle according to claim 1, wherein, The shaft lock is embedded in the cylinder and arranged radially along the mandrel, the shaft lock is provided with an air inlet hole, the second air channel is arranged in the cylinder to communicate the air inlet hole with the gas source device outside, and the shaft lock can be in contact with the outer wall of the mandrel under the action of air pressure to lock the mandrel.

7. The air levitated precision wafer dicing electrospindle according to claim 6, wherein, The shaft lock comprises a shaft lock sleeve, a shaft lock pin, a shaft lock spring and a shaft lock plug; the shaft lock sleeve and the shaft lock plug are embedded in the cylinder barrel, the shaft lock sleeve is open at both ends, and the shaft lock plug is fixed at one end of the shaft lock sleeve away from the mandrel; the shaft lock pin is placed in the shaft lock sleeve, the shaft lock spring is sleeved on the shaft lock pin, one end of the shaft lock spring is pressed against the shaft lock pin, and the other end of the shaft lock spring is pressed against the inner wall of the shaft lock sleeve; the air inlet hole is arranged on the shaft lock sleeve, and the air inlet hole is communicated with the gap between the shaft lock pin and the shaft lock plug.

8. The air levitated precision wafer dicing electrospindle according to claim 7, wherein, The outer peripheral wall of the shaft lock sleeve is annularly provided with a gas guide groove, the air inlet hole is arranged on the groove bottom of the gas guide groove, and the air inlet hole is provided with at least one.

9. The air levitated precision wafer dicing electrospindle according to any of claims 1-8, characterized in that, An installation plane parallel to the axis of the mandrel is arranged on the outer wall of the cylinder barrel, and a mounting block is further fixed on the outer wall of the cylinder barrel, the mounting block is provided with a hoisting plane parallel to the installation plane, and a plurality of connecting thread connection holes are reserved on the hoisting plane.

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