JPH02212071A - Polishing device for crystal blank sheet - Google Patents

Abstract

PURPOSE:To prevent the generation of a defective working caused by the ununiformalization of the development state of a polishing material by performing polishing while vibrating each polishing sheet, the carrier interposed by each polishing sheet and a work by a specific high frequency. CONSTITUTION:Lapping plates 5, 6 are rotated. In this case, the vibration by an electromagnet 16 is applied on the whole lapping plates 5, 6 including motors 1, 2 and the polishing material easy to cause an ununiform development at the rotation time of the lapping plates 5, 6 is uniformly dispersed. Consequently, the max. standstill friction force between a carrier 8 and the lapping plates 5, 6 is reduced and the force grinding a crystal blank sheet 10 is uniformized on the contact face.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an improvement in a polishing apparatus for polishing thin crystal plates and the like.

(Prior art) Like a crystal plate used as a crystal resonator, μm31
When manufacturing elements that require a thin wall thickness of about 100 mL, it is common to use a polishing apparatus as shown in FIGS. 3(a) and 3(b), for example.

That is, the polishing apparatus shown in FIG. 3 (al) includes a pair of upper and lower motors 1.2 as driving sources, and a pair of upper and lower lapping plates (polishing plates) 5 that are rotated by the output shafts 1a and 2a of each motor 1.2, respectively. .6, the carrier 8 (FIG. 3(b)) sandwiched between the wrap plates 5 and 6, the crystal blank lO as a workpiece inserted and supported in the support hole 9 of the carrier 8, and each motor! , 2, and a control device 11.+2.

Powdered abrasive material is interposed between each lap plate 5, 6 and the crystal blank plate 10.

In the above configuration, by fixing one wrap plate and rotating the other wrap plate, or by rotating both wrap plates in mutually opposite directions, one side of the crystal blank 10 held by the carrier 8 or By polishing both sides, the base plate can be made thinner. The limit of the thinness of the blank plate 1O is determined by the thickness of the carrier 8.

By the way, in order to increase the launch frequency of the crystal resonator, it is necessary to finish the base plate thinly, and if the carrier 8 is made thinner in order to make it thinner, the mechanical strength of the carrier will decrease, and if polishing is performed in this state, the carrier This tends to cause deformation and breakage, and as a result, it has a negative effect on the machining accuracy of the blank plate, making it extremely difficult to process high-frequency crystal blank plates.

In addition, in polishing, the surface of the base plate is cut with an abrasive material while rotating the upper and lower lap plates, but the abrasive material tends to be spread unevenly, which causes the gap between the carrier and the lap plate to be uneven. Frictional force becomes uneven, causing defective products.

(Object of the Invention) The present invention has been made to solve the problems of the conventional polishing apparatus as described above. In polishing equipment that polishes while rotating,
It is an object of the present invention to provide a polishing device that can prevent processing defects caused by non-uniform development of abrasive material.

(Summary of the Invention) In order to achieve the above-mentioned object, a quartz crystal plate polishing apparatus according to the present invention rotates polishing plates while slidingly contacting the upper and lower surfaces of a workpiece held by a carrier, thereby polishing the workpiece. In equipment that performs processing.

The present invention is characterized in that the polishing process is performed while vibrating each of the polishing plates and the carrier and work sandwiched between the polishing plates at a predetermined high frequency.

(Examples) Hereinafter, the present invention will be described in detail based on examples shown in the accompanying drawings.

FIG. 1 is a schematic diagram showing the configuration of a polishing apparatus according to the present invention, and the same parts as in FIG. 3 are given the same reference numerals.

The polishing apparatus of the present invention is characterized in that a permanent magnet 15 is integrated into one motor l, and an electromagnet 16 is disposed directly above the permanent magnet 15 to face it.

The electromagnet 16 is controlled by the vIJ 11 section 18, such as switching the magnetic direction or turning on/off electricity. That is, the electromagnet 16
By alternately switching the direction of the current to the permanent magnet 15, the permanent magnet 15 can repeat repulsion and attraction to vibrate the lap plate 5.6 connected to the motor l, and can also turn the current to the electromagnet 16 on and off. A similar vibration effect can be obtained by

By controlling the magnetism from the electromagnet 16 in this manner, the permanent magnets 15 arranged opposite to each other are excited.

The entire device including the lap plate can be vibrated at a predetermined frequency. The excitation frequency is controlled by the control unit 18, and the vibration direction is preferably the vertical direction (direction perpendicular to the lap plate surface), and the zero frequency is, for example, 50 to 60 MHz.
Set to .

The operation of the embodiment of the present invention having the above configuration will be explained.

That is, one or both of the lap plates 5.6 rotates as in the conventional example, but when vibrations are applied by the electromagnet 16 to the entire lap plate 5.6 including the motor 1, the rotation of the lap plates causes an error. The abrasive material, which tends to spread uniformly, becomes uniformly dispersed. As a result, the maximum static frictional force between the carrier and the lap plate is reduced, and the force that scrapes the crystal blank becomes uniform on the contact surface, improving the performance of the device.

FIG. 2 shows another embodiment of the present invention, in which an ultrasonic transducer (magnetostrictive vibrator) 20 is used instead of the vibration mechanism consisting of an electromagnet and a magnet, and a controller 2I that drives and controls the ultrasonic transducer 20. It has a configuration in which vibration is applied to the lap plate etc. using

In this case as well, it is possible to provide an excitation effect according to the frequency of the ultrasonic waves applied to the ultrasonic transducer 20.

(9! Bright effect) As described above, according to the present invention, in a polishing device that polishes a work sandwiched between lap plates disposed vertically in parallel, when the lap plates rotate, the abrasive spreads. It is possible to prevent processing defects caused by non-uniform conditions.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing the configuration of a polishing apparatus according to the present invention, FIG. 2 is an explanatory diagram of a second embodiment of the present invention, and FIG.
at (b) is an explanatory diagram of a conventional example. 1, 2 layered plate) 10 ・ Place + 8 ・ User... Motor 5.6... Wrap plate (Grinding 8... Carrier 9... Support hole

Claims (1)

[Scope of Claims] An apparatus that performs polishing by rotating polishing plates in sliding contact with the upper and lower surfaces of a workpiece held by a carrier, comprising: each polishing plate; A crystal blank polishing apparatus characterized in that the polishing process is performed while vibrating a carrier and a workpiece at a predetermined high frequency.