JPH0545381B2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a surface polishing method.

[Prior Art] For example, a surface polishing device such as a lapping machine or a polishing machine includes upper and lower surface plates that are rotatably arranged around a common shaft, a sun gear, and an internal gear. The workpiece held in the workpiece holding hole of the carrier that meshes with these gears is sandwiched between the upper and lower surface plates, and with the desired machining pressure applied to the workpiece by both surface plates, the carrier is planetary driven by both gears. The workpiece is machined by rotating the upper and lower surface plates while moving, but there is a problem in that the workpiece tends to crack or chip when the machining is finished. That is, in the past, at the end of machining, a sizing device or a timer was used to simultaneously reduce the rotational speed of the surface plate and the machining pressure. A situation similar to no load occurs,
The workpiece, which had previously been pressed against only one side of the holding hole in the carrier, is momentarily released from the processing pressure and increases its degree of freedom, causing it to lose its balance and move irregularly back and forth, left and right, and repeatedly collide with the carrier. , cracking and chipping are likely to occur.

[Problems to be Solved by the Invention] An object of the present invention is to provide a surface polishing method that eliminates the above-mentioned conventional drawbacks and does not cause cracking or chipping of the workpiece.

[Means for Solving the Problems] In order to solve the above problems, the present invention provides a method in which a workpiece is held in a workpiece holding hole of a carrier that meshes with a sun gear and an internal gear, and the workpiece is sandwiched between upper and lower surface plates. With these surface plates applying a constant machining pressure to the workpiece, the sun gear and internal gear rotate the carrier while rotating the upper and lower surface plates to polish the workpiece. After the machining is complete, In the above-mentioned surface polishing method in which the surface plate and gears are stopped and the pressure applied by the surface plate is released to take out the workpiece, steady processing is performed in which the upper and lower surface plates are rotated at a constant speed while a constant processing pressure is applied to the workpiece. After performing this for a certain period of time, deceleration processing is performed for a certain period of time by reducing the number of revolutions of the surface plate to a predetermined number while keeping the processing pressure the same. This method is characterized by gradually decelerating and, after the surface plate has stopped, pressurizing the workpiece is released and the workpiece is taken out.

[Operations and Effects] According to the present invention, after performing steady machining in which the upper and lower surface plates are rotated at a constant speed while applying a constant machining pressure to the workpiece, the rotation of the surface plate is continued while the machining pressure remains unchanged. Deceleration machining is performed to reduce the number of workpieces to a predetermined number for a certain period of time, then the machining pressure is lowered to perform depressurization machining, the surface plate is gradually decelerated, and after the surface plate has stopped, the pressure on the workpiece is increased. Since the work is released and taken out, no load condition occurs unlike the conventional method in which the rotational speed and machining pressure are reduced at the same time, and therefore the work can be held securely to the end. This makes it possible to reliably prevent cracks and chipping caused by collisions with the carrier as the workpiece moves freely.

[Specific Examples of the Invention] Hereinafter, the surface polishing method of the present invention will be explained in more detail with reference to the drawings.

FIG. 1 schematically shows a surface polishing apparatus used for carrying out the method of the present invention, in which 1 indicates a lower surface plate;
2 is an upper surface plate, 3 is a sun gear, 4 is an internal gear, 5 is a carrier meshing with both gears 3 and 4, and 6 is a workpiece held in a workpiece holding hole of the carrier 5.

The lower surface plate 1 is arranged to be rotatable by a motor 8 via a gear 7, and the upper surface plate 2 is
It is rotatably suspended from a rod 11 of a cylinder 10 via a hanging plate 9, and is raised and lowered by the expansion and contraction of the rod 11, and when the rod 11 is lowered, the drive shaft 12
It is configured to be engaged with the upper driver 13 and driven and rotated by the motor 8 via the drive shaft 12. Furthermore, a sun gear 3 and an internal gear 4
is also connected to the motor 8 or other drive source through a suitable transmission mechanism, and is driven to rotate, and the carrier 5 is rotated by the sun gear 3.
planetary motion around.

A rotation speed control device and a machining pressure control device are connected to the motor 8 and cylinder 10, respectively. The rotational speed control device includes a low-speed speed setting device 14a and a high-speed speed setting device 14b for setting the rotational speed of the motor 8 in two stages, and these speed setting devices 14a and 14b are equipped with a relay or the like. The switching device 15 is switchable, while the processing pressure control device includes a low pressure circuit 18a and a high pressure circuit consisting of regulators 16a, 16b, 16c and solenoid valves 17a, 17b, 17c, which can arbitrarily set the output pressure. The low pressure circuit 18a and the high pressure circuit 18b are connected in parallel between the head chamber 10a of the cylinder 10 and the fluid source 19.
A reverse pressure circuit 18c is connected between the fluid source 19 and the solenoid valves 17a, 17
A control device 20 is connected to the switching device 15 in the rotation speed control device and the rotation speed control device.

When polishing the workpiece 6 using the above-mentioned surface polishing apparatus, first, the solenoid valves 17a and 17c are turned on by the control device 20, and the head chamber 10a and rod chamber 10b of the cylinder 10 are opened. , low pressure circuit 18a and reverse pressure circuit 18
The fluid pressures set by the regulators 16a and 16c at c are respectively supplied, and the low machining pressure P ₁ (Fig. 2) determined by the pressure difference between these pressures and the load on the upper surface plate 2 is applied to both surface plates 1, It acts on the workpiece 6 sandwiched between the two. Next, motor 8
The upper and lower surface plates 1 and 2 and both gears 3 and 4 are activated by
Machining of the workpiece 6 is started by the drive circuit of
T After _one hour, when the rotational speed of the motor 8 reaches the set speed V ₂ of the high-speed speed setting device 14b, the solenoid valve 17b is turned on and the solenoid valve 17a is turned off, so that the high-pressure circuit 18b is connected. The fluid pressure in the chamber 10a increases and the processing pressure acting on the workpiece 6 increases to _P2 .

Steady machining is carried out in this state for T ₂ hours, and when the steady machining is completed, the machining pressure is maintained at P ₂ and the low-speed speed setting device 14a is changed via the switching device 15 according to a command from the control device 20. is turned on and the motor 8 is decelerated to the set speed _V1 , thereby performing deceleration machining for _T3 hours. Then, when deceleration processing is performed for a predetermined period of time, the motor 8
At the same time as the stop command is issued, the solenoid valves 17a and 17b are switched on and off, and the machining pressure is switched to low pressure (P ₁ ), and the workpiece 6 is held in a low pressurized state while the surface plate 1, Source pressure machining was performed for T ₄ hours by gradually reducing the speed of motor 8.
stops.

When the motor 8 stops, the pressure on the workpiece 6 is also released, the upper surface plate 2 is lifted by the cylinder 10, and the workpiece 6 that has been machined is taken out.

The switching times of the rotational speed and machining pressure mentioned above can all be set by a timer, but when using a sizing device, the timing of deceleration and pressure reduction can be set based on the actual machining dimensions. . In other words, if the sizing device outputs a deceleration command when the workpiece 6 reaches a specific size just before sizing, and when the workpiece 6 is further polished and reaches the sizing, a depressurization command is output. good.

It goes without saying that the rotational speed and processing pressure may be controlled not only by the illustrated control device but also by other appropriate means.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an apparatus suitable for carrying out the method of the present invention, and FIG. 2 is an explanatory diagram of its operation. 1, 2...surface plate, 3...sun gear, 4...internal gear, 5...carrier, 6...work.

Claims (1)

[Claims] 1. A workpiece is held in a workpiece holding hole of a carrier that meshes with a sun gear and an internal gear, and the workpiece is sandwiched between upper and lower surface plates, and a constant machining pressure is applied to the workpiece by these surface plates. In this state, the workpiece is polished by rotating the upper and lower surface plates while causing the carrier to make planetary motion using the sun gear and internal gear. After finishing the machining, the surface plate and gears are stopped and the surface plate is used for polishing. In the surface polishing method in which the pressure is released and the workpiece is removed, after a certain period of steady machining in which the upper and lower surface plates are rotated at a constant speed while a constant machining pressure is applied to the workpiece, the machining pressure is left as it is. Deceleration machining is performed by reducing the number of revolutions of the surface plate to a predetermined number for a certain period of time, then processing pressure is reduced to perform depressurization machining, the surface plate is gradually decelerated, and after the surface plate has stopped, the workpiece is A surface polishing method characterized by releasing the pressure and taking out the workpiece.