JP4189135B2 - Tool length confirmation method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention includes a pressure foot that preliminarily defines a position in the height direction for holding a tool as a tool holding position, and manages the length from the tool holding position to the tool tip to a constant value for machining. The present invention relates to a method for confirming the blade length of a tool in a printed circuit board processing machine.
[0002]
[Prior art]
FIG. 3 is a block diagram of a conventional printed circuit board processing machine, FIG. 4 is a cross-sectional view of a spindle tip, and FIG. 5 is a cross-sectional view of a tool diameter confirmation device.
[0003]
In FIG. 3, the table 1 is movable on the bed 2 in the X direction in the figure by a driving means (not shown). On the surface of the table, a printed circuit board 3, a tool cassette 5 for holding various drills 4, a tool mounting post 6 for exchanging the drill 4, and a tool diameter confirmation device 7 are placed for each spindle 8. .
[0004]
The housing 9 that holds the spindle 8 is movable in the Y direction perpendicular to the X direction and the Z direction perpendicular to the X and Y directions by the driving means (not shown) on the front surface of the cross rail 10 fixed to the bed 2. is there. A tool changer 11 is fixed to the housing 9. The tool changer 11 includes a cylinder 12 and a chuck portion 13 held at the tip of a piston rod that can be raised and lowered in the Z direction.
[0005]
As shown in FIG. 4, the drill 4 includes a blade portion 4t, a shank portion 4s, and a tapered portion 4c that connects the blade portion 4t and the shank portion 4s. The drill ring 20 having a thickness T is attached to the shank portion 4s of each drill 4 so as not to easily move. The drill ring 20 is positioned in advance so that the upper end 20 a is a distance A from the tip of the drill 4. The collet chuck 21 of the spindle 8 holds the drill 4 such that the lower end is in contact with the upper end 20 a of the drill ring 20.
[0006]
A pressure foot 22 is fitted on the outer periphery of the spindle 8 so as to be movable in the Z direction. The movement stroke S0 of the pressure foot 22 is about 15 mm, and is urged downward in the figure by a cylinder (not shown). When moving in the horizontal direction, the lower end 22u is configured to be lower than the tip of the drill 4 by L0 (about 1 mm) as indicated by a two-dot chain line in the drawing.
[0007]
As shown in FIG. 5, a hole 24 is formed in the holder 23 constituting the tool diameter confirmation device 7, and the light emitter 25 a is located at a position L <b> 2 from the upper end (the height from the surface of the table 1 is K). A light transmission type sensor 25 comprising a light receiver 25b is arranged. The optical axis M of the sensor 25 is orthogonal to the axis of the hole 24.
[0008]
When machining, first, the tool changing device 11 places the drill 4 held in the tool cassette 5 on the tool mounting post 6. Then, as shown in FIG. 6, the lower end of the drill ring 20 is positioned at a height J from the surface of the table 1. Therefore, when the lower surface of the collet chuck 21 is positioned at a position of J + T from the surface of the table 1 and the drill 4 is held, the lower surface of the collet chuck 21 comes into contact with the upper end 20a and the tip of the drill 4 comes from the surface of the table 1 (J + T -A) height. The position of J + T is preset in the NC device of the printed circuit board processing machine as the tool holding position H0 (= J + T).
[0009]
Next, as shown in FIG. 7A, after the pressure foot 22 is raised to the end of the moving stroke, the axis of the spindle 8 is positioned at the axis of the hole 24, and then the tip of the drill 4 is moved from the optical axis M. Positioned downward by a predetermined distance a (for example, a = 0.5 mm when the diameter of the drill 4 is 1.5 mm), and the diameter D1 of the tip of the drill 4 is measured from the amount of change in the amount of light received by the light receiver 25b. To do. Next, as shown in FIG. 5B, the machining depth S1 specified in advance in the machining program is lowered, and the diameter D2 of the rear end portion of the drill 4 is measured. When D1 ≧ D2, the machining is performed, and when D2> D1, the drill 4 is replaced with another drill 4.
[0010]
According to the above procedure, even if the drill 4 is replaced, the tip position of the drill 4 is always the same, so there is no need to check the tip position of the drill every time the drill 4 is replaced, and work efficiency can be improved. it can.
[0011]
Moreover, since the pressure foot 22 pressurizes the printed circuit board 3 before the drill 4 cuts into the printed circuit board 3 at the start of processing, the position accuracy of the holes can be improved. Moreover, since the printed circuit board 3 is pressurized until the drill 4 comes off from the printed circuit board 3 at the end of the processing, no flash is generated on the surface, and the processing quality can be improved.
[0012]
And since the blade length of the drill 4, ie, the length of the blade part 4t, is not less than the processing depth S1, processing with excellent quality can be performed without causing processing defects.
[0013]
[Problems to be solved by the invention]
Here, the movement stroke S0 of the pressure foot 22 is 15 mm, the distance L0 between the lower end 22u of the pressure foot 22 and the tip of the drill 4 during the movement is 1 mm, and the distance L2 from the upper end of the holder 23 of the optical axis M is 5 mm. And In this case, the substantial movement stroke of the pressure foot 22 is 14 (15-1) mm. Therefore, the blade length of the drill 4 that can be measured is less than 9 mm.
[0014]
Normally, the board thickness of the printed circuit board is about 1.6 mm, so even when three printed circuit boards are stacked and processed, the total board thickness is about 5 mm, and the processing depth exceeds 6 mm. Absent. Therefore, even if the length of the drill 4 that can be measured is less than 9 mm, there was no particular problem.
[0015]
In recent years, processing of a multilayer substrate having a thickness of about 9 to 13 mm obtained by laminating a plurality of printed circuit boards has been required. However, if the movement stroke of the pressure foot provided in the printed circuit board processing machine is 15 mm and the measurement position of the drill diameter of the tool diameter confirmation device is 5 mm from the upper end, the necessary blade length cannot be measured. . For this reason, processing must be performed using a printed circuit board processing machine having a sufficiently large moving stroke, and the production efficiency is low.
[0016]
The object of the present invention is to use a conventionally used apparatus (for example, a pressure foot with a moving stroke of 15 mm and a tool diameter confirmation apparatus with a measuring position of 5 mm from the upper surface) to determine the blade length of a drill having a blade length exceeding 9 mm. It is in providing the trill blade length confirmation method which can be confirmed .
[0017]
[Means for Solving the Problems]
In order to achieve the above object, according to the present invention, a position in the height direction for holding a tool is determined in advance as a tool holding position, and the length from the tool holding position to the tool tip is managed at a constant value. the diameters of the rear end portion of the tip of the tool is detected respectively, the tool on the printed board machining apparatus having a pressure foot you determine whether to use the tool, measured on the basis of both the comparison result In the blade length confirmation method, when the movement distance of the pressure foot is shorter than the movement distance required for confirming the blade length of the tool, the position for holding the tool is set to be greater than the tool holding position. The upper position is set to an upper position, and after the confirmation, the position in the height direction for holding the rear portion is returned to the predetermined tool holding position .
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described based on the illustrated embodiments.
[0019]
FIG. 1 is a flowchart showing a procedure for measuring a blade length according to the present invention. When the machining command is received, the NC device sets i = 0 (procedure S10), and compares the machining depth S1 with 8 mm with reference to the machining program (procedure S20). When the machining depth S1 ≧ 8, after setting i = 1 (procedure S30), the drill 4 placed on the tool mounting post 6 is held with the tool holding height H set to H = H0 + S1-8 (procedure S30). S40), the process of step S60 is performed. When S1 <8, the tool holding height H is set to H = H0, the drill 4 placed on the tool mounting post 6 is held (step S50), and the process of step S60 is performed. In step S60, the diameter D1 of the tip end portion of the drill 4 and the diameter D2 of the rear end portion of the drill 4 are measured by the same procedure as before. Then, the diameter D2 and the diameter D1 are compared (procedure S70). If D1 ≧ D2, the process of step S90 is performed. If D2> D1, the drill 4 is replaced with another drill 4 (procedure S80). Perform the following process.
[0020]
In step S90, i and 1 are compared. If i ≧ 1, the process of step S100 is performed. In other cases, the process is terminated, and processing of the printed circuit board is started.
[0021]
In step S100, the held drill 4 is returned to the tool mounting post 6. Then, after holding the drill 4 with the tool holding height H set to H = H0 (procedure S110), the processing is terminated and the processing of the printed circuit board is started.
[0022]
As shown in FIG. 2, the collet chuck 21 holds the shank 4s at the position (S1-8) from the upper surface 20a by the processing of step S40, that is, when the blade length exceeds 8 mm. Even if it exists, the diameter D2 of the rear-end part of the drill 4 can be measured.
[0023]
As described above, according to the present invention, a blade length exceeding 8 mm can be measured using a conventional apparatus.
[0024]
In the above description, the processing depth S1 is compared with 8 mm. However, the processing depth S1 may be compared with other values.
[0025]
Moreover, although the case of the drill was demonstrated above, this invention is applicable also to other tools, such as an end mill and a drill bit.
[0026]
【The invention's effect】
As described above, according to the present invention, when the blade length exceeds the normal length, the drill holding position is changed when checking the blade length. The blade length can be confirmed .
[Brief description of the drawings]
FIG. 1 is a flowchart showing a procedure for measuring a blade length according to the present invention.
FIG. 2 is a diagram showing a drill holding position when a drill having a long blade length is measured.
FIG. 3 is a configuration diagram of a conventional printed circuit board processing machine.
FIG. 4 is a cross-sectional view of a spindle tip portion.
FIG. 5 is a cross-sectional view of a tool diameter confirmation device.
FIG. 6 is a cross-sectional view of a tool mounting post.
FIG. 7 is a diagram showing a conventional blade length measurement procedure.
[Explanation of symbols]
4 Drill 8 Spindle 21 Collet chuck H0 Tool holding position

Claims (1)

The height direction position for holding the tool is determined in advance as the tool holding position, and the length from the tool holding position to the tool tip is managed to a constant value ,
The diameters of the rear end portion of the tip of the tool is detected respectively, both the comparison results to the printed board machining apparatus of the tool in having a pressure foot you determine whether to use the tool, measured on the basis of In the blade length confirmation method,
When the movement distance of the pressure foot is shorter than the movement distance required for confirming the blade length of the tool, the position for holding the tool is a position above the tool holding position,
After completion of the confirmation, the blade length confirmation method of a tool, characterized in that to return the position in the height direction for holding the rear in the tool holding position said predetermined.

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