CN102728866B - Drilling processing machine - Google Patents

Abstract

Provided is a drilling machine capable of always positioning the position of the axis (O) of a drill at a preset position to improve machining accuracy. Equipped with: a mandrel motor (20), equipped with a collet (22) for holding the drill (12) and rotating the drill (12); an air cylinder (30), for opening and closing the collet (22); a sleeve (50), which supports the spindle motor (20) to move freely in the direction of the axis (O); the sleeve bracket (51), which has a sleeve (50) inside, can move in two directions at right angles to the direction of the axis (O). The through hole (51a) (space) that moves upward; and the air cylinder (52) that fixes the sleeve (50) relative to the sleeve bracket (51) in the XYZ three-axis direction. By holding the positioning reference pin (60) arranged on the table (2) by the collet (22), the position of the sleeve (50) relative to the sleeve support (51) is determined via the collet (22), and then Secure the socket (50) to the socket bracket (51).

Description

Hole processing machine

technical field

The present invention relates to a drilling machine.

Background technique

A conventional printed circuit board hole drilling machine as a hole drilling machine will be described.

Fig. 8 is an overall perspective view of a first conventional printed circuit board hole drilling machine for forming holes in a printed circuit board.

The table 2 is movably supported by a guide unit 3 disposed on the machine base 1 , and is driven in the X direction on the machine base 1 by a screw feed mechanism (not shown). On the upper surface of the table 2, a processing area 2a on which a printed circuit board is placed, and a tool supply area 2b for supplying drills used for processing are set.

The pillar 4 is fixed on the base 1 across the workbench 2 . The horizontal slide 5 is movably supported by a guide unit 6 disposed on the support 4 , and is driven in the Y direction on the support 4 by an unillustrated screw feed mechanism using a motor 7 as a drive source. The pair of saddles 8 are movably supported by a guide unit 9 disposed on the horizontal slide plate 5 , and are driven in the Z direction by an unillustrated screw feed mechanism using a motor 10 as a drive source.

A pair of spindle units 11 is fixed to each saddle 8 . The spindle unit 11 is formed by a case fixed to the saddle 8 and supporting the spindle motor, and the spindle motor. The drill bit 12 is rotatably supported on the front end of the spindle motor.

The NC device 28 controls the motors and the like of each axis.

And the printed circuit board is fixed on the processing area 2a of the workbench 2, and after the workbench 2 and the transverse slide plate 5 are relatively moved in the X, Y directions to carry out the positioning of the printed circuit board and the drill bit 12, the slide saddle 8 A hole is formed on a printed circuit board by moving in the Z direction (Patent Document 1).

Hereinafter, the second prior art will be described.

When the moving speed of the drill 12 is increased, machining efficiency can be improved. Therefore, instead of moving the saddle 8, the spindle motor is supported by the case in advance so that it can move freely in the Z direction, and only the spindle motor is moved to increase the moving speed of the drill, that is, increase the machining speed.

9 is a front partial cross-sectional view of a drill drive unit (hereinafter referred to as "spindle") in a conventional printed circuit board drilling machine that moves only the spindle motor during processing, and the parts that are the same as those in FIG. Reference numerals are used to omit description.

The box body 4 is fixed on the saddle 8 . The cylindrical spindle motor 20 is positioned in the XY direction on the housing 4 so that the axis O is in the Z direction, and is movable in the axis O direction inside the housing 4 via a bearing 24 .

The rotor shaft 21 of the spindle motor 20 is radially supported by a plurality of bearings 25 and positioned in the axis O direction. A not-shown rotor (rotator) is disposed on the rotor shaft 21 , and is rotatable by a not-shown winding (stator).

An air cylinder 30 is disposed above the spindle motor 20 . The moving direction of the piston rod 31 is coaxial with the axis O. As will be described later, the front end of the piston rod 31 of the air cylinder 30 in the standby position faces the rear end 22 b of the collet 22 with a gap therebetween.

One end of a connecting rod 35 is fixed to an upper portion of the cylinder 30 by a bolt 36 . The other end of the connecting rod 35 is connected with the output shaft end of the linear motor 40 . The linear motor 40 moves the connecting rod 35 in the Z direction. The linear motor 40 is fixed on the saddle 8 .

According to the above configuration, by operating the linear motor 40, the spindle motor 20, that is, the drill 12 can be moved in the Z direction.

Next, the procedure for holding the drill 12 will be described.

FIG. 10 is a cross-sectional view of the front end of the spindle motor 20 .

A collet 22 and a spring 23 urging the collet 22 upward in the figure are arranged at the front end portion of the rotor shaft 21 . A plurality of slits (not shown) are formed on the side of the drill 12 of the collet 22 along the axis O of rotation, and the diameter can be reduced in the radial direction.

And the drill bit 12 is held by radial force generated by the tapered surface 22 a formed on the outer periphery of the collet 22 being urged by the spring 23 to the tapered surface 21 a formed on the inner surface of the rotor shaft 21 .

Next, the procedure for attaching and detaching the drill 12 will be described.

The air cylinder 30 is operated when the drill bit 12 is replaced. Then the piston rod 31 descends, so that the collet 22 overcomes the spring 23 and moves downward in the figure. Since the collet 22 opens when the tapered surface 22a of the collet 22 leaves the conical surface 21a of the rotor shaft 21, the holding force of the collet 22 to the drill bit 12 disappears, so the drill bit 12 can be removed from the collet 22. Down. And in this state, after inserting the new drill bit 12 into the inside of the collet 22, when the piston rod 31 is raised, the collet 22 rises under the action of the spring 23, and the collet 22 is closed, so that the drill 12 can be kept at Spindle motor 20 on. In addition, the shank diameter of the drill 12 used in the printed circuit board drilling machine is formed to have the same diameter regardless of the nominal diameter of the drill.

However, since the temperature of each part of the printed circuit board drilling machine rises through processing, the axis O of the drill bit 12 deviates from the design value, so the processing accuracy decreases.

Therefore, there is a printed circuit board hole drilling machine that detects and arranges above the table in all directions before drilling a workpiece placed on a table that can move in the X direction. The axes of the multiple tools supported by the respective front ends of the multiple mandrels on the transverse slide plate moving in the Y direction orthogonal to the X direction relative to the axes on the mandrel design in the X direction and the Y direction are calculated. The average value of each deviation in each direction of the detection, with respect to the center coordinates of the hole of the axis coordinates of the plurality of mandrels 12 to be processed, only the average value is compensated in each direction, so that the hole is drilled on the workpiece (patent document 2).

[Patent Document 1] Japanese Unexamined Patent Publication No. 11-347865

[Patent Document 2] JP-A-2007-988

According to the technique of Patent Document 2, when a plurality of drills are used to form holes on the printed circuit board as many as the number of drills, positional deviation of the holes drilled on the printed circuit board can be reduced. However, since the magnitude of the positional deviation cannot be reduced, the machining accuracy cannot be improved.

Contents of the invention

An object of the present invention is to provide a drilling machine capable of always positioning the position of the axis O of the drill at a preset position and improving machining accuracy.

In order to solve the above-mentioned problems, the drilling machine according to the first aspect of the present invention includes: a spindle motor provided with a collet for holding a tool and rotating the tool; a case supporting the spindle motor during the rotation of the tool Move freely in the axial direction of the above-mentioned tool; the moving assembly makes the above-mentioned spindle motor move in the axial direction of the rotation of the above-mentioned tool; The above-mentioned box moves, and it is characterized in that, instead of the above-mentioned box, there is provided: a sleeve, which supports the above-mentioned spindle motor to move freely in the axis direction of the rotation of the tool; a space for movement in two directions at right angles to the axis of rotation of the tool; and a fixing unit for fixing the sleeve relative to the sleeve holder in the three-axis directions of XYZ.

In this case, if an axis capable of supporting the rotation of the spindle motor with the tool is provided between the spindle motor and a moving unit that moves the spindle motor in the direction of the axis of rotation of the tool A coupling that moves in two directions at right angles, and a fixing unit that fixes the spindle motor relative to the coupling in three directions of XYZ are more effective.

Since the axis O can always be positioned at a preset position, machining accuracy is improved.

Furthermore, since it is not necessary to detect in advance the deviation of the axis O of the drill from a preset position, the axis O can be positioned efficiently.

Description of drawings

Fig. 1 is a front partial cross-sectional view of a drill driving part in a printed circuit board drilling machine related to the present invention;

Fig. 2 is a drawing showing the movement range of the main shaft in the printed circuit board drilling machine related to the present invention;

Fig. 3 is the top view of the workbench in the printed circuit board drilling machine involved in the present invention;

Fig. 4 is a flow chart illustrating the positioning steps of the main shaft in the present invention;

FIG. 5 is a diagram illustrating specific actions in step S150 in FIG. 4;

FIG. 6 is a diagram illustrating specific actions in step S160 in FIG. 4;

Fig. 7 is the accompanying drawing that shows the 2nd embodiment of the present invention;

FIG. 8 is an explanatory diagram of the prior art;

Fig. 9 is an explanatory diagram of the prior art;

FIG. 10 is a cross-sectional view of the front end of the spindle motor 20 .

Explanation of reference signs:

2: Table, 12: Drill, 20: Mandrel motor, 22: Collet, 30: Cylinder, 50: Sleeve, 51: Sleeve holder, 51a: Through hole, 52: Cylinder, 60: Positioning reference pin , O: axis.

detailed description

Hereinafter, the present invention will be described with reference to the drawings.

【Example 1】

FIG. 1 is a front partial cross-sectional view of a drill driver in a printed circuit board drilling machine according to the present invention, corresponding to FIG. 9 of the prior art. In addition, the same code|symbol is attached|subjected to the part which is the same as FIG. 8, FIG. 9 or the part with the same function, and redundant description is abbreviate|omitted. In addition, in this embodiment, a pair of drill driving parts having the same structure is provided.

A cylindrical sleeve 50 having a flange portion 50a formed at one end portion fixes the cylindrical spindle motor 20 in the X and Y directions through the bearing 24, and supports the spindle motor 20 in the axis O direction. Move freely. The lower surface of the flange portion 50 a is in contact with the upper surface of the sleeve holder 51 . Two through-holes 50c are formed in the flange portion 50a. The lower surface of the flange portion 50a and the upper surface of the sleeve holder 51 are finished into smooth surfaces.

A through hole 51 a (space) is formed along the axis O direction at the center portion of the sleeve holder 51 . Assuming that the shank diameter of the drill is d, the diameter of the through hole 51a is D1, and the outer diameter of the cylindrical portion 50b of the sleeve 50 is D2, the diameter D1 is D1≦D2+d.

Air cylinders 52 are arranged on both sides of the sleeve holder 51 in the Y direction. The interaxial distance of the piston rod 52a of the air cylinder 52 is equal to the interaxial distance of the through hole 50c.

And the diameter of the through-hole 50c is larger than the diameter of the piston rod 52a by (D2+d-D1) or more. A square pressing plate 53 is fixed to the tip of the piston rod 52a. The short side of the pressing plate 53 is larger than the diameter of the through hole 50c.

Except for predetermined cases, the cylinder 52 applies force to the sleeve 50 downward in the figure, and fixes the sleeve 50 relative to the sleeve holder 51 . Hereinafter, the case where the cylinder 52 biases the sleeve 50 downward in the drawing is referred to as "fixing the sleeve 50". Furthermore, it is called "opening the sleeve 50" when the air cylinder 52 stops urging the sleeve 50 downward in the figure.

A hollow 40 b having a circular cross section is formed at the end of the output shaft 40 a of the linear motor 40 . A flange portion 35f having a circular cross section is formed at the other end of the connecting rod 35 . The gap g (the difference between the height of the cavity 40 b in the Z direction and the thickness of the flange portion 35 f ) is g=0.1 to 0.5 mm. Moreover, the diameter of the cavity 40d is larger than the diameter of the flange part 35f by (D2+d-D1) or more. A coupling is formed by the cavity 40b of the output shaft 40a and the flange portion 35f. The lower surface of the flange portion 35f and the bottom surface of the cavity 40b (the surface on which the lower surface of the flange portion 35f abuts) are finished to be smooth.

Two air cylinders 54 are arranged at the end of the output shaft 40a. And except for a predetermined case, the air cylinder 54 biases the flange portion 35f upward in the figure, and fixes the flange portion 35f to the output shaft 40a. Hereinafter, the state where the air cylinder 54 urges the flange portion 35f upward in the drawing is referred to as "fixing the connecting rod 35". In addition, the state where the air cylinder 54 stops urging the flange part 35f upward in a drawing is called "opening the connection rod 35".

Positioning reference pins 60 are arranged in the tool supply area 2 b of the table 2 . The diameter of the positioning reference pin 60 is the same as the diameter of the shank of the drill bit 12, and the tip is formed into a spherical surface with a radius of d/2. Furthermore, the length of the straight portion of the positioning reference pin 60 is 15 to 20 mm. On a circle having a diameter Ds centered on the axis P of the positioning reference pin 60 , four holes 61 for distance sensors (here, air sensors) not shown are arranged at intervals of 90 degrees in the circumferential direction. The diameter Ds of the circle in which the hole 61 is arranged is Ds<dk−ds when the outer diameter of the collet 22 is dk and the diameter of the hole 61 is ds. The position of the positioning reference pin 60 in the Y direction will be described later.

FIG. 2 is a diagram showing the movement range of the spindle S, and FIG. 3 is a plan view of the table 2 . Hereinafter, let the main shaft S on the left be the main shaft S1, and the main shaft S on the right be the main shaft S2, and when it is necessary to distinguish the structural elements such as the cylinder 54 for each main shaft S, the letters i are added to the respective reference numerals ( Where i is 1 or 2) for distinction (for example, the cylinder 541 is the cylinder 54 for the spindle S1, and the cylinder 542 is the cylinder 54 for the spindle S2).

Assuming that the center of the table 2 in the Y direction is Y0, the axis O1 of the drill driver S1 moves between the Y coordinate −Y1 and +Y coordinate y1 as shown in FIG. 2 . Furthermore, the axis O2 of the drill driver S2 moves between the Y coordinate −y1 and the Y coordinate +Y1. Here, y1 is in the range of 10 to 20 mm.

As shown in FIG. 3, in the tool supply area 2b, a drill reducing sleeve 70 for holding a drill bit 12 for replacement is provided for each S2 spindle S1, S2, and a drill reducing sleeve 71 for receiving the drill bit 12 held by the spindle S1, And a plurality of drill bit reducing sleeves 73 that hold the drill bit. The positioning datum pin 60 is positioned at the same position as the Y coordinate of Y0 (that is, the center of the workbench 2 ), and the X coordinate of the reducing sleeves 70 and 71 of the drill bit.

Next, the positioning procedure of the spindle S will be described.

FIG. 4 is a flowchart illustrating the positioning procedure of the spindle S. As shown in FIG. In addition, the main shaft Si is positioned at a position where the front end of the collet 22i is higher than the table 2 by a predetermined height (standby position) of the positioning reference pin 60 .

When the positioning instruction of the main shaft S is issued, i=1 (step S100 ), and the axis Oi of the main shaft Si (here, the main shaft S1 ) is positioned on the axis P of the reference pin 60 (step S110 ). Next, the number of trials n is set to n=1 (step S120 ), and the sleeve 50 i and the connecting rod 35 i are released (steps S130 , S140 ). Next, open the collet 22i (step S140), activate the linear motor 40, lower the spindle motor 20i, and lower the front end of the collet 22i to a height of (0.5+g) mm from the surface of the table 2 (step S140). S150). When the connecting rod 35i is opened, the front end of the collet 22i only drops g under the action of gravity, so the front end of the collet 22i at the end of step S150 is 0.5 mm higher than the surface of the table 2. . Next, it is checked whether the four distance sensors are all on (step S160 ), and if the four distance sensors are all on, the process of step S170 is performed, and in other cases, the process of step S300 is performed. In step S170, the collet 22i is closed, and then the sleeve 50i and the connecting rod 35i are fixed (steps S180, S190). Next, the collet 22i is opened (step S200), and the front end of the collet 22i is raised to the standby position (step S210). Next, it is checked whether i=2 (step S220 ), and when i is 2, the collet 22 i is closed (step S230 ), and the process ends. Moreover, when i is not 2 in step S220, the process of step S110 is performed after setting i=i+1 (step S240).

It is confirmed in step S300 whether or not the number of trials n is greater than 3, and if n is 3 or less, the process of step S310 is performed, and when n is greater than 3, a warning is displayed and the device is stopped. In step S310, the number of trials n is set to n=n+1, and the sleeve 50i and the connecting rod 35i are fixed (steps S320, S330). Next, after raising the front end of the collet 22i to the standby position (step S340), the process of step S130 is performed.

In addition, the processing after step S240 is the operation of the spindle S2.

Next, specific operations in the ascending step will be described.

FIG. 5 is a diagram illustrating specific operations in step S150.

When the axis Oi of the collet 22 i deviates from the axis P of the reference pin 60 , the collet 22 i comes into contact with the spherical portion of the positioning reference pin 60 . Assuming that the pressing force of the linear motor 40 relative to the positioning reference pin 60 is F, and the opening angle of the collet 22i is 2θ, a vertical force of N=Fsinθ acts on the portion where the collet 22i contacts the spherical surface. The effect, therefore, is that the collet 22i, ie the sleeve 50i, moves horizontally towards the axis P due to the application of a horizontal force of f=Ncosθ=Fsinθconθ. And through step S170, the axis Oi and the axis P are coaxial. Therefore, when step S230 ends, the axis O1 of the main axis S1 and the axis O2 of the main axis S2 have the same X coordinate, and the interval in the Y direction is located by the distance Y1.

FIG. 6 is a diagram illustrating specific operations in step S160.

Normally, the sleeve 50i moves horizontally toward the axis P by step S150, but as shown in FIG. 6, the axis Oi may be inclined with respect to the axis P for some reason. In this case, since the distance sensor on the side of the collet 22i away from the surface of the table 2 is disconnected, the inclination of the axis Oi can be prevented.

In this embodiment, since three more attempts are made even in the case where the axis Oi is inclined for some reason, it is possible to prevent the device from stopping. In addition, usually, the axis Oi and the axis P can be aligned by the second step S150.

[Example 2]

FIG. 7 is a diagram showing a second embodiment of the present invention, and parts that are the same as those in FIG. 1 or have the same functions are given the same reference numerals and their descriptions are omitted.

In this embodiment, no cavity 40b is formed at the end of the output shaft 40a of the linear motor 40, and the connecting rod 35 is fixed to the output shaft 40a.

When the deviation of the axis Oi from the axis P is small (50 μm or less), the axis Oi and the axis P can be aligned by bending the connecting rod 35 by utilizing the elasticity of the connecting rod 35 .

In addition, since the positioning procedure of the main shaft Si can be easily understood from the positioning procedure of the first embodiment, its description is omitted.

As described above, according to the present invention, since the spindle S1 and the spindle S2 can be accurately positioned at the designed positions, high-precision machining can be performed. Moreover, it is of course possible to process a printed circuit board according to each of the main shafts S1 and S2, and even in the case of processing one printed circuit board using both the main shaft S1 and the main shaft S2, it is possible to obtain the same overall processing of the printed circuit board. The same machining accuracy as the case where the area is machined by one spindle.

Furthermore, even when there is one main shaft, it is not necessary to measure the displacement of the main shaft in advance by applying the present invention, so the machining efficiency can be improved.

In addition, the movable range of the sleeve 50 relative to the sleeve holder 51 is less than ±d/2 (for example, a maximum of about ±1.5 mm when the shank diameter of the drill bit is 3.175 mm), but due to the In the case of the case, the deviation from the design value of the axis O at the time of manufacture is ±10 μm or less, and even the maximum thermal deformation is ±100 μm, so the range of movement of the sleeve 50 relative to the sleeve holder 51 is practically no problem.

Claims (2)

1. a drilling processing machine, comprising: support; Workbench, is supported relative to above-mentioned support with moving freely in the X direction; Cross slide, is supported relative to the pillar be fixed on above-mentioned support with moving freely in the Y direction; Saddle, is supported by above-mentioned cross slide and moves freely in z-direction; Spindle motor, possesses the collet for retaining tool and above-mentioned instrument is rotated; Casing, supports above-mentioned Spindle motor and moves freely on the axis direction of the rotation of above-mentioned instrument, and be fixed on above-mentioned saddle; Moving assembly, makes above-mentioned Spindle motor move on the axis direction of the rotation of above-mentioned instrument; And shutter device, make above-mentioned collet opening and closing, this drilling processing machine makes above-mentioned Spindle motor move relative to above-mentioned casing, it is characterized in that,

Replace above-mentioned casing and be provided with: sleeve, supporting above-mentioned Spindle motor and move freely on the axis direction of the rotation of above-mentioned instrument; Bush support, its inside possesses above-mentioned sleeve can the space of movement in the both direction that the axis direction of the rotation with above-mentioned instrument is right angle; And fixation kit, above-mentioned sleeve is fixing on three direction of principal axis of XYZ relative to above-mentioned bush support,

And on above-mentioned workbench, be provided with reference pins, above-mentioned Spindle motor is positioned on said reference pin, above-mentioned fixation kit is open, by above-mentioned collet is opened, above-mentioned Spindle motor is declined, after making the axis direction of the rotation of above-mentioned instrument consistent with the axis of said reference pin, be fixed with above-mentioned fixation kit.

2. drilling processing machine as claimed in claim 1, it is characterized in that, between above-mentioned Spindle motor and the moving assembly making the movement on the axis direction of the rotation of above-mentioned instrument of above-mentioned Spindle motor, be provided with the shaft coupling that can support movement in both direction that above-mentioned Spindle motor is right angle at the axis direction of the rotation with above-mentioned instrument, and by fixation kit fixing on XYZ tri-directions relative to above-mentioned shaft coupling for above-mentioned Spindle motor.