JPS63199889A - Method for positioning body to be plated before partial plating - Google Patents

Abstract

PURPOSE:To allow the positions of a mask and a body to be plated to accurately and stably coincide with each other by detecting the direction and dimensions of position gap between a pin and a pilot hole in the body to be plated from the mechanical displacement of the pin given during the insertion of the pin into the hole. CONSTITUTION:When a pin 1 is inserted into a pilot hole 4a or a hole for positioning in a body 4 to be plated so as to position the body 4 before partial plating, mechanical displacement is given to a pin part consisting of the pin 1 and a pin holder 2 by force from the hole 4a or the like. The displacement is detected with a displacement detector 6 fitted to an outer tube 5. The direction and dimensions of position gap between the pilot hole 4a or the like and the pin 1 are detected from the detected displacement. The body 4 to be plated is moved so that the dimensions of position gap are made zero.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a method for accurately aligning a mask and an object to be plated when performing partial plating on an object to be plated such as an IC lead frame or a connector frame. It is something.

[Prior Art] Plated objects such as IC lead frames or connector frames are punched out from a long strip using a press or the like and then formed, and then only the necessary portions are plated with gold, silver, or the like. When plating with a so-called coil-to-coil method, in which a long strip is sent out in a coil, subjected to partial plating, and then wound again into a coil, the movement of the long strip is temporarily stopped at the plating point, and the section is placed in a stationary state. It is often carried out in an intermittent manner, in which plating is performed and then a long strip is removed by the length of the plating.

Partial plating is performed by pressing a mask with holes that define the plating area onto the object to be plated.
In order to improve the positional accuracy of partial plating, it is necessary to improve the alignment accuracy between the mask and the object to be plated. For this reason, a common method is to insert a pin into a pilot hole or positioning hole that has been punched out in the lead frame in advance, and then correct the position of the lead frame by inserting the pin and align it to the correct position. There is.

[Problems to be Solved by the Invention] However, in such a method, the length of the lead frame is shortened due to thermal expansion due to temperature changes in the lead frame or the structural material of the plating apparatus, or due to tension applied to the lead frame. There is a problem in that the positioning changes in reality, making it impossible to perform highly accurate positioning.

That is, in the method of pulling a fixed length of a long strip due to the above-mentioned thermal expansion or the like, an error will occur in the length to be pulled. When this error δ exceeds the value δMAX (where the pin diameter is φ, δMAX", φ/2 Further, as the plating mask length becomes longer, and thus the take-off length becomes longer, this tendency becomes stronger, and it becomes difficult to set the take-off length.

There are two or three methods to deal with this problem. The most rudimentary method is to have a person visually check the pin, or sound an alarm if the pin cannot be inserted, and then manually adjust the length of the pull-out each time. Of course, this method has serious problems that not only requires manpower but also reduces the yield of the product.

Another possible method is to transmit light through a pilot hole or the like and receive the light with an optical sensor or the like to detect the position of the lead frame or the like. Generally, plating is performed at high temperatures, so some of the liquid may evaporate or scatter.
There are problems such as if water adheres to the light source or receiver and is used for a long period of time, light will no longer pass through it, or if water adheres to the pilot hole, the light will be refracted and a detection error will occur.

In addition, if the object is heavier than the object to be plated,
Or, if it requires force to move due to frictional force, etc., even if you try to insert the pin, the pin will only bend or the pilot hole will become deformed due to insufficient strength of the pin or pilot hole. ,
As a result, there was a problem in that alignment could not be performed.

SUMMARY OF THE INVENTION An object of the present invention is to solve the problems of the prior art described above and to provide a method for accurately, simply, and stably aligning a mask and an object to be plated.

[Means for solving the problem] The alignment method according to the present invention detects the mechanical displacement of the pin when the pin is inserted, thereby determining the direction of misalignment between the pin and the pilot hole or positioning hole of the object to be plated. Furthermore, by detecting the positional deviation dimension and feeding it back to, for example, the length of the object to be plated, the positional deviation dimension can be easily corrected.

[Embodiment] FIG. 1 is a block diagram for explaining an embodiment of the present invention. In the first method A, first in step 1,
A preset length of the object to be plated is taken out, and then in step 2, a pin is inserted into the pilot hole of the object to be plated, and the mechanical displacement of the pin is detected by a displacement detector. Detects the direction and size of positional deviation between the pin and the like. Then, the take-off length is further slightly moved so that the output of the displacement detector (representing the positional deviation dimension) becomes zero, that is, so that the pin comes to the center of the pilot hole (step 1 is performed again). Finally, when the mask and the object to be plated have been aligned as described above, in step 3, partial plating of the object to be plated is performed. Even if the pin is not completely inserted into the pilot hole, if the tapered part of the tip touches the pilot hole, it will cause mechanical displacement, which will move the object to be plated to the correct position, resulting in The pin can be inserted easily and high alignment accuracy can be easily obtained.

In the second method B, first, in step 1, a predetermined length of the object to be plated is removed, and then in step 2, a pin is inserted into a pilot hole or the like of the object to be plated.
By detecting the mechanical displacement of the pin with a displacement detector,
The method is exactly the same as the first method A until the direction and size of the positional deviation between the pilot hole and the pin are detected.

However, in the second method B, even if the displacement detector detects a misalignment dimension, that is, even if the pin hits the edge of the pilot hole and is slightly bent, this is ignored and the process proceeds to step 3. Proceed and perform partial plating. Then, at the time of the next take-up in step 1, the take-up length is adjusted so that the previous output of the displacement detector becomes zero, and then the work is taken off.

In this case, it is necessary to investigate the relationship between the output of the displacement detector and the displacement dimension in advance, and an example thereof is shown in FIG.

Note that the first method allows highly accurate alignment every time, but the adjustment time for alignment is slightly longer, for example, 2.
It takes ~5 seconds. The second method, on the other hand, does not require any adjustment time, so the takt time can be shortened, but alignment errors occur within the range. For example, at the start ±0.
After repeating the test for about 2 times and 5 to 10 times, a variation of about ±0.07 ov occurred.

FIG. 3 is a diagram showing a schematic configuration of the pin insertion displacement detection device, in which the pin 1 is detachably attached to the pin holder 2. The pin holder 2 is attached to the device main body 3 by its necking portion 2a. When the pin is inserted, the pin portion consisting of the pin 1 and the pin holder 2 is given an appropriate mechanical displacement by the force from the pilot hole 4a of the object to be plated 4. This displacement is detected by a displacement detector 6 attached to the outer cylinder 5, for example, an eddy current displacement meter.

The outer cylinder 5 is structured to move up and down together with the pin portion to prevent the plating solution from adhering to the inside of the outer cylinder.

[Effect of the invention] According to the present invention, the following effects can be obtained.

(1) The method of displacement of the object to be plated can be easily detected, and automatic operation without the need for human intervention is possible.

(2) Since there is no need to forcefully insert the pin, the pilot hole will not be deformed and the quality of the product will be improved.

(3) High positioning accuracy can be easily obtained even when taking over a long period of time.

[Brief explanation of the drawing]

Fig. 1 is a block diagram for explaining an embodiment of the method of the present invention, Fig. 2 is a graph showing the relationship between the output of the displacement detector and the displacement dimension, and Fig. 3 is the pin insertion displacement detection device section. It is a figure showing a schematic structure of. 1: pin, 2: pin holder, 2a: necking part of pin holder, 3: apparatus main body, 4: object to be plated, 4a: pilot hole of object to be plated, 5: outer cylinder, 6: displacement detector. 1st first baseman Kazuaki 212] Position 1°” dimention (pull 1

Claims (1)

[Claims] (1) When performing partial plating on an object to be plated, align the mask and the object to be plated to determine the plating area by inserting a pin into a pilot hole or positioning hole provided in the object to be plated. In the method of A method for positioning an object to be plated during partial plating, characterized in that the object to be plated is moved and aligned so that the object to be plated is aligned.