JPH0328517B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides an electroforming tank in which a body to be electroformed is rotatably supported and inserted, and a part of the body is parallel to the body at a predetermined interval within a plane including the axis of the rotating shaft. The present invention relates to a rotary body electroforming apparatus in which a plurality of columnar electrodes for electroforming are arranged to face the electroformed object, and the positions of the tips of the electrodes facing the electroformed object are respectively controlled.

Generally, in electroforming, the highest importance is placed on the transfer accuracy of the electroformed object, and various inventions and ideas have been made regarding the arrangement and control of electrodes for this purpose.
Control of the thickness of the electroformed shell has not yet been adequately controlled. However, if the electroformed shell has thin parts, its strength and service life will be reduced, and if it has too thick parts, materials, electricity, working time, etc. will be wasted. Furthermore, if there is a thin portion, the thin portion may result in a defective product when machining the electroformed shell. Controlling the thickness of the electroformed shell in this way is as important as transfer accuracy, and the present inventor has previously developed a device for controlling the thickness of the electroformed shell, for example, in Japanese Patent Publication No. Showa 55
-Disclosed in Publication No. 145191. However, in the device disclosed herein, a plurality of electrodes are appropriately distributed and contact detectors are distributed between these electrodes, and these distributed contact detectors have their tips and electroformed The distance between the electroformed shell and the electroformed shell is fixed in advance so as to have the desired thickness. Then, when the electroformed shell produced by electroforming comes into contact with the tip of the fixed contact detector, the contact detection circuit is activated and reduces the amount of current flowing to the electrodes near the contact detector. Or the power is cut off.

Although this conventional device is simple and inexpensive, it has the disadvantage that it cannot be detected and controlled at all during the electroformed shell generation process because the contact detector and electrode are both fixed. As a result, even if the contact detector detects the generated electroformed shell and de-energizes the electrodes in its vicinity, the thickness of the electroformed shell will gradually increase due to the influence of other energized electrodes. Not only does this increase the noise level, but it also has the disadvantage of leaving traces of the fixed contact detector.

The present invention provides that when an electroformed object is rotatably installed in an electroforming tank into which an electroforming solution is injected, at least the leading end of the electroformed object is an electrode or an electrode. A rod having a rod is normally moved in the axial direction by the operation of the rod control section, and when the leading end of the moving rod comes into contact with the electroformed object and the rod stops, the position of the rod at that time is measured with a measuring instrument. Measure and use the measuring instrument as the origin. Then, the position of the electrode is set by appropriately retracting the rod based on the measuring instrument that is the origin, and the position of the rod is controlled from this position according to the rotation angle of the electroformed object. After further applying a specified amount of current to the rotating electroformed body and the electrode, the rotation of the electroformed body is stopped at a fixed position, and the rod is moved toward the electroformed shell that is formed there. The thickness of the electroformed shell is measured based on the difference between the measured value of the measuring device when the leading end comes into contact with the electroformed shell and stops, and the measured value taken as the origin. If this measurement is performed at one or several locations on the rotating electroformed object, the position of the electrode, the amount of current, or the rotation speed or rotation angle of the electroformed object can be controlled based on this measurement value. The purpose of this is to obtain an electroformed shell having a desired thickness.

Next, the present invention will be explained based on illustrative figures.
1 and 2 are a side sectional view and a plan view of an embodiment of the present invention, and as shown in the figures, at least the leading portion of the electroformed body 2 is rotatably installed in the electroforming tank 1. are electrodes, or the rods 4 having electrodes are placed in a plane parallel to the rotation axis of the electroformed body 2 (4A, 4B, 4).
A plurality of rods 4 are arranged at predetermined intervals between adjacent rods 4A, 4D, and each rod 4 is driven in the axial direction by each rod control device 5A, 5B, 5C, 5D, and is energized. Approaching the casting body 2,
The details of the movement will be explained with reference to FIGS. 3, 4, and 5.

In FIG. 3, 4 is one of the many rods 4 arranged in the desired plane facing the electroformed object 2, and is arranged so as to penetrate the electroforming tank 1. The rod 4 is sealed with a seal 6 to prevent the electroforming liquid 3 from leaking around the rod 4, and the rod 4 can be moved in its axial direction. At the tip of the rod 4, a columnar head 7 is screwed and fixed coaxially with the rod 4, and in a cavity 8 provided in the screwed head 7, an electrode 9 for electroforming is connected to an insulating layer 10. It is inserted so that it can slide in the axial direction through the. A terminal 11 is embedded and fixed in the rod 4 at the end of the cavity 8, and a conductive spring 12 that can conduct electricity is stretched between the terminal 11 and the electrode 9. Due to the elasticity of the spring 12, the electrode 9 is constantly pushed out toward the tip of the leading portion 7. Since a window 13 is provided in the leading portion 7, the tip of the electrode 9 passes through this window 13 and is exposed into the electroforming liquid 3. In order to insert this electrode 9 into the cavity 8 of the leading part 7, a hole (not shown) large enough to allow the electrode 9 to be inserted and taken out is provided on the side of the leading part 7, and this hole is If the electrode 9 is inserted into the cavity 8 of the leading part 7 through the
It can be attached and detached extremely easily. A wiring hole 14 is provided in the rod 4, and a wiring 15 passing through the wiring hole 14 connects the terminal 11 and the electroforming power source 3.
2 are linked. Rack 1 installed on rod 4
6 is engaged with pinion 17, and this pinion 1
7 is rotated by a servo motor 18. The rod 4 moves by the rotation of this servo motor 18.
The position is measured by a measuring device 19 such as an encoder, potentiometer, magnetic scale, etc., which is connected to the rod 4. The rod 4 and the electroformed body 2 are connected to the terminals of a measuring power source 20 via this measuring device 19, and the rod 4 and the electroformed body 2 or the electroformed shell 2' formed thereon are connected to each other. When they make contact, a weak current flows through them (Figure 3). When the rotation of the servo motor 18 is stopped using this weak current as a signal and the rod 4 is stopped, the measuring device 19 comes to measure the position of the rod 4 at that time based on the signal or a desired delay signal of the signal. ing. Here, if it is not preferable to flow a current between the electroformed body 2 and the rod 4, or if an insulating material is used for the leading part 7, or if the leading part 7 contacts the electroformed body 2, the pressure If it is desired to adjust the angle, it is recommended to use the structure shown in FIG. Its structure is such that a sleeve 22 is pivotally supported on a rod 4, and a rack 33 provided on the sleeve 22 meshes with a pinion 17 similar to that described in FIG. A spring 24 is provided between the sleeve 22 and the rod 4, and the elasticity of the spring 24 causes the sleeve 22 to come into contact with the collar 25. However, since this collar 25 is fixed to the rod 4 by a pin 26, the movement of the sleeve 22 by the spring 24 is stopped at this collar 25. A magnet 27 is embedded in the rod 4 inside the sleeve, and the sleeve 2
2 is provided with a sensor 28 which detects the magnet 27 and operates. The relationship between the leading end 7 screwed onto the rod 4 and the electrode 9 inserted therein is the same as that explained in FIG. The case of determining the thickness and measuring the thickness of the electroformed shell 2' will be explained. First, when the servo motor 18 is rotated to rotate the pinion 17, the sleeve 22 that engages with the pinion 17 moves the rod 4 toward the electroformed object 2 via the spring 24. When the leading end 7 of the rod 4 comes into contact with the electroformed body 2 or the electroformed shell 2', the rod 4 stops, but the sleeve 22
compresses the spring 24 and continues to move. When the sensor 28 provided on the sleeve 22 detects the magnet 27 provided on the rod 4, the rotation of the servo motor 18 is stopped, and when a detection signal from the sensor 28 or a signal delayed from the signal is obtained, the measuring device 19 measures the position of the moving rod 4. At this time, the contact pressure between the electroformed body 2 and the top part 7 is determined by the elasticity of the spring 24, so if you want to adjust the contact pressure, you can adjust the contact pressure to some extent by replacing the spring 24 or shifting the position of the sensor 28. can be adjusted. For example, if you want to increase the contact pressure, you can move the sensor 28 away from the magnet 27 and increase the amount of compression of the spring 24 after the tip 7 contacts the electroformed object 2. The contact pressure can be increased. In FIG. 1, 29 is a numerical control device, 30 is a program device, and 31 is a key.
In the three-dimensional shape of the electroformed object 2, the electric field strength on the surface of the electroformed object 2 can be determined by the following equation, and the electrode 9 is driven according to this equipotential surface. Numerically control the placement.

E=-∂v/∂n=δ/ε E=electric field E=gradV V; potential (XYZ) δ; surface charge density n; outward normal ▽ ² V=-δ/ε (Poisson's equation) In this case, the rod 4 and the electrode 9 are the electroformed body 2.
The drive is controlled so that it moves while keeping it perpendicular to the surface.

The electroforming tank 1 is fixed to the 42nd part fixed to the base 41. A pair of beams 44 are provided on the top of a column 43 fixed to a base 41, and a head 46 is supported on two bars 45 fixed between the pair of beams 44. A servo motor 47 provided in the head 46 can rotate while controlling its rotation angle with an encoder 48. A chuck 50 is fixed to the tip of a shaft 49 which is pivotally supported by a head 46 which can be rotated by a servo motor 47. By engaging the spindle 2A of the electroformed object 2 with the claw 51 of the chuck 50, the electroformed object 2 is rotatably inserted into the electroforming tank 1. A servo motor 52 provided on the head 46 moves the shaft 49 in its axial direction, and 53 is an encoder that measures the amount of movement. In this way, the rotational support device for the electroformed body 2 is constituted by the head 46 or chuck pawl 51.

When carrying out electroforming in the present invention, the electroformed object 2 having a desired shape is set in the electroforming tank 1 by being caught between the claws 51 of the chuck 49, and the electroforming liquid 3 of a predetermined prescription is placed in the electroforming tank 1.
When the electroforming tank 1 is filled with the desired electroforming shell thickness, the desired thickness of the electroforming shell, the prescription or type of the electroforming liquid 3, the voltage of the electroforming power supply 32, etc. are entered into the key 31, and the program is started according to the input. Once the electroformed object 2 is stopped at a fixed angle position by the servo motor 47 via the device 30 and the numerical control device 29, the rod control devices 5A, 5B,
Control signals are sent to 5C and 5D. First, the position of each electrode 9 is set. The operation is performed by each rod control device 5 according to the command from the numerical control device 29.
A servo motor 18 rotates the pinion 17 to move each rod 4 toward the electroformed object 2. As described above, each servo motor is stopped when the leading end 7 of each rod 4 comes into contact with the electroformed object 2, and the position of each rod 4 at that time is measured by the measuring device 19. When the leading end 7 first comes into direct contact with the electroformed object 2, electroforming has not been performed and there is no electroformed shell 2', so the measured value of the measuring device 19 at that time is This is stored in the numerical control device 29 as the origin position. Next, the servo motor 18 is reversed to move the rod 4 away from the electroformed object 2, but the amount of movement at this time must be a predetermined amount. For example, the third
In Fig. 4, when the distance between the electroformed body 2 and the leading part 7 reaches l, or the distance l+a, which is the distance from the tip of the leading part 7 to the end surface of the electrode 9, reaches a predetermined value. The position of the end face of the electrode 9 at that time is a position that corresponds to a predetermined equipotential surface in the electric field at a predetermined angular position of the electroformed body 2, which is a cathode.

When all the rods 4 have been arranged in this way, the voltage of the electroforming power source 32 is applied to the electroformed object 2 through the wiring 15, and to the electrode 9 through the terminal 11 and spring 12, and the servo motor 47 is activated. Electroforming is performed while rotating the electroformed body 2 in the direction of arrow E in FIG. At that time, when the tip of the rod 4 comes to the straight part a-b or the concave part c-d of the electroformed object 2, the distance between those surfaces and the electrode 9 changes, so the rod 4 is moved according to the amount of change. 4 is controlled in movement by a rod control device 5. Movement control at this time is performed by commands from the numerical control 29. After electroforming has been carried out for a desired time in this manner, the thickness of the electroformed shell 2' formed on the electroformed object 2 is measured.
In this measurement, once the electroformed object 2 is stopped at a predetermined position by the servo motor 47 as in the measurement of the origin position of each rod 4 described above, the servo motor 18 is actuated to move the rod 4 into the electroformed object 2. When the rod 4 moves in the opposite direction, the leading end 7 of the rod 4 comes into contact with the electroformed shell 2' formed on the electroformed body 2. The position of the rod 4 at this time is measured by the measuring device 19, and the difference between the measured value and the measured value as the origin position of the rod 4 already stored in the numerical control device 29 is determined by the generated electroformed shell 2'.
It can be calculated as the thickness t. If the thickness t of the electroformed shell 2' produced in this way can be measured for each rod, it is possible to change the distance l+a between the electroformed body 2 and the electrode 9 for each rod 4. The numerical control device 2 controls the electroformed shell 2' to obtain the desired thickness by changing the rotation angle and rotation speed of the servo motor 47, changing the amount of current, etc.
9.

According to the present invention, the distance between the electroformed object 2 and the opposing tips of a plurality of electrodes 9 arranged at predetermined intervals in the same plane as the rotation axis is measured for each electrode 9. The interval position between the two can be set, and the set position can be changed while measuring the thickness of the electroformed shell 2' at any time during the production process of the electroformed shell 2'.
This has the effect that an electroformed shell having a desired shape and thickness can be produced by changing the amount of current applied.

In carrying out the present invention, the shaft 49 can be controlled by the motor 52 so as to move in and out of the electroforming tank 1, and the thickness measurement of the electroformed shell 2' can be performed using the electroformed body 2. Electroforming can be performed while the rod 4 is continuously moved by the rod control device 5 based on the measured value. The electrode 9 at the head of the rod may be a wear-resistant platinum-plated titanium electrode with an exposed structure or a consumable electrode made of plated metal, and the present invention also includes such modified configurations. .

[Brief explanation of drawings]

Fig. 1 is a conceptual diagram of a device according to an embodiment of the present invention viewed from the side and partially cut away, Fig. 2 is a plan view, and Figs. A detailed diagram of the rod control device, Figure 5, is shown in Figure 3.
Fig. 4 is a view taken in the direction of arrow A in Fig. 4; 1... Electroforming tank, 2... Electroformed object, 3... Electroforming liquid, 4, 4A, 4B... Rod, 5, 5A, 5B
... Rod control device, 7 ... Leading section, 9 ... Electrode, 19 ... Measuring instrument, 29 ... Numerical control device, 3
2...Electroforming power supply, 46...Head, 47...Servo motor, 50...Chuck.

Claims (1)

[Scope of Claims] 1. An electroforming tank into which an electroforming solution is injected, a rotational support device that supports an electroformed object, and a rotational shaft of the rotational support device whose axis is located within a plane that includes the axis of the rotational shaft. As shown in FIG. A rotating body electroforming device equipped with a rod control device. 2. The electroforming device for a rotating body according to claim 1, wherein the rotational support device that supports the electroformed body is stopped at a fixed position. 3. An electroforming device for a rotating body according to claim 1, wherein the device for moving the rod in the axial direction moves the rod in the axial direction in relation to the rotation of the rotation support device. 4. The rotation according to claim 1, wherein the device for moving the rod in the axial direction moves the rod along a substantially equipotential surface of the electroformed object supported by the rotation support device. Body electroforming device. 5. Electroforming of a rotating body according to claim 1, characterized in that the rotational support device that supports the electroformed body can rotate the electroformed body by an arbitrary angle from a predetermined position and then stop the electroformed body. Casting equipment.