JP3418453B2 - Cooling device for spindle unit in printed circuit board processing machine - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cooling device for a spindle unit in a printed circuit board processing machine. 2. Description of the Related Art A printed circuit board processing machine has a configuration as shown in FIG. That is, the table 3 movably supported along the linear guide device 2 fixed on the bed 1 is driven by the motor 4 via the screw feed mechanism. Column 5 is the bed 1
Fixed to. A cross slide 7 movably supported along a linear guide device 6 fixed to the column 5,
It is driven by a motor 8 via a screw feed mechanism. The saddle 9 is movably supported by a linear guide device (not shown) fixed to the cross slide 7, and is driven by a motor 10 via a screw feed mechanism. Tools (not shown)
A spindle unit 11 that supports a spindle (not shown) that rotates while holding is fixed to the saddle 9. [0003] The pressure foot 12 comprises a main shaft unit 1.
2 is supported at one end so as to be movable in the axial direction of the spindle. The pressure foot 12 is provided with a pipe 1 for collecting dust.
3 is connected to the dust collecting device 14. The cooling device 15 is connected to the spindle unit 11 via a pipe 16, and circulates a liquid refrigerant through a passage formed in the spindle unit 11 to cool the spindle unit 11. Then, a spindle holding a required tool is rotated at a required number of revolutions, and a dust collector 14 is operated to suck the inside of the pressure foot 12 through a pipe 13. In this state, the table 3 on which the workpiece W is placed
And the cross slide 7 are relatively moved in the X and Y directions to make the tool face the processing position of the workpiece, and then the saddle 9 is lowered. Then, first, the pressure foot 12 contacts the work W and presses the work W. Further, when the saddle 9 is lowered, the main spindle unit 11 and the pressure foot 12 move relatively, and the tool bites into the work W to process the work W. At the same time, since the spindle unit 11 becomes hot due to the heat generated by the motor that rotates the spindle, the cooling device 15 is operated at regular time intervals (5 to 15 minutes) to circulate the refrigerant in the spindle unit 11. The temperature of the spindle unit 11 in a required temperature range (a temperature difference of 8 to
(10 degrees). [0006] The intermittent operation of the cooling device causes the main spindle unit and the saddle or the cross slide to repeatedly contract and expand, thereby deteriorating the accuracy of the printed circuit board processing machine itself. . Further, for example, in a drilling machine for a printed circuit board, several to ten or more kinds of drills having different diameters (from about 0.2 to 6.3 mm) or more kinds are exchanged (replacement time is short). Drill while performing (about 30 seconds). Further, the number of holes to be machined may be several to tens of thousands depending on the diameter of the hole to be machined. For this reason, if the cooling device is operating when drill exchange is frequently performed, the spindle unit becomes too cold, out of the required temperature range, and processing position accuracy and processing quality (for example, the inner surface of the processed hole). Surface roughness). In view of the above circumstances, an object of the present invention is to provide a cooling device for a spindle unit in a printed circuit board processing machine capable of performing processing in a stable state by reducing a temperature change of the spindle unit. . In order to achieve the above object, according to the present invention, there is provided a spindle unit in a printed circuit board processing machine in which chips generated from a processing portion are suctioned and collected by a dust collecting device. A housing supporting the main shaft, a plurality of air intakes formed at one end of the housing from a plurality of air inlets formed at predetermined intervals toward the other end in parallel with the axis of the main shaft. A plurality of exhaust passages formed at predetermined intervals from the air passage to the one end in parallel with the axis of the main shaft; A main shaft unit having an annular exhaust path connecting the end of the path to an exhaust port, a pipe connecting the exhaust port to the dust collector, and a flow regulator arranged in the middle of the pipe are provided. Was. When the main shaft is rotating, the flow rate of the air flowing through the intake passage, the ventilation passage, and the exhaust passage formed in the housing of the main shaft unit is increased by the flow regulator,
When the rotation of the spindle is stopped, such as when exchanging a workpiece or replacing a tool, the intake path, ventilation path, The temperature of the spindle unit is controlled within a relatively narrow range by reducing the flow rate of air flowing in the exhaust path and preventing the supercooling of the spindle unit. An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows a printed circuit board processing machine to which the present invention is applied. In FIG. 1, the same components as those in FIG. 6 are denoted by the same reference numerals. At the upper end of the spindle unit 11, a plurality of intake ports 20 and one exhaust port 2 are provided at predetermined intervals.
1 is formed. The exhaust port 21 is connected to a pipe 17 in which a flow controller 18 is arranged on the way.
The other end of 7 is connected to dust collector 14. FIGS. 2 to 5 show the spindle unit 11 shown in FIG. 1. In FIG.
A main shaft 23 rotatably supported on the housing 22 via an air bearing (not shown).
And a rotor 24 integrally formed with the main shaft 23, and a stator 25 fixed to the housing 22 so as to face the rotor 24. The rotor 24 and the stator 25 constitute a high-frequency motor. The spindle 23
At one end, a chuck is arranged to support the tool 19 in a detachable manner. A plurality of intake ports 20 formed at predetermined intervals in the upper end of the housing 22 form an intake passage 26 extending toward the lower end in parallel with the axis of the main shaft 23, and a lower end of the housing 22. An annular ventilation path 27 connecting the intake paths 26, a plurality of exhaust paths 28 extending from the ventilation path 27 to the upper end in parallel with the axis of the main shaft 23,
An annular exhaust path 29 connecting each exhaust path 28 at the upper end of 2
This exhaust path 29 is connected to the exhaust port 21. Further, the air flowing out of the thrust bearing formed at the lower end of the housing 22 is supplied to the housing 2 by the stator 2.
An exhaust path 30 for blowing toward 5 is formed and connected to the exhaust port 21. Therefore, when the dust collector 14 operates,
The air sucked from the intake port 20 passes through the intake path 26, the ventilation path 27, the exhaust path 28, and the exhaust path 29, and is sucked into the dust collector 14 from the exhaust port 21. At the same time, the air flowing out of the thrust bearing portion is also blown to the stator 25,
It is sucked into the dust collecting device 14 from the exhaust port 21. At this time,
The heat of the housing 22 is removed to cool the housing 22, and the stator 25 is also directly cooled by the air blown from the exhaust passage 30. With such a configuration, after the warm-up operation for a predetermined time, the dust collector is operated, and suction from the pressure foot 12 and cooling of the spindle unit 11 are started. At this time,
Since the state of heat generation from the bearing unit supporting the main shaft 23 and the motor unit differs depending on the operation state (whether the main shaft is rotating or stopped) of the printed board processing machine, it is oscillated by the control device for controlling the printed board processing machine. The flow controller 22 adjusts the amount of air exhausted from the exhaust port 21 in synchronization with a command (a processing command, a tool change command, etc.). For example, when the main shaft 23 is rotating, 15 to 20 l
/ Sec, when the main shaft 23 is stopped, the flow rate of the air is reduced from a fraction to about a tenth, thereby reducing the main spindle unit 11 during rotation of the main shaft 23.
Therefore, it is possible to perform processing within a relatively narrow and stable temperature range by preventing the temperature rise of the main shaft 23 and preventing a sharp decrease in temperature when the spindle 23 is stopped. As described above, according to the present invention, there is provided a cooling device for a spindle unit in a printed circuit board processing machine in which chips generated from a processing portion are suctioned and collected by a dust collecting device. A housing supporting the main shaft, at one end thereof, a plurality of intake passages formed from a plurality of intake ports formed at predetermined intervals toward the other end in parallel with the axis of the main shaft,
An annular ventilation path connecting the ends of the intake path, a plurality of exhaust paths formed at predetermined intervals from the ventilation path toward the one end in parallel with the axis of the main shaft, and an end of each exhaust path. Since a main shaft unit formed with an annular exhaust path connecting the portion to the exhaust port, a pipe connecting the exhaust port to the dust collector, and a flow regulator arranged in the middle of this pipe were provided. Processing can be performed within a relatively narrow and stable temperature range,
Processing position accuracy, processing quality, and the like can be improved.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a printed circuit board processing machine to which the present invention is applied. FIG. 2 is a sectional view of the spindle unit shown in FIG.
FIG. FIG. 3 is a sectional view taken along line BB in FIG. 2; FIG. 4 is a sectional view taken along line CC in FIG. 2; FIG. 5 is a sectional view taken along line DD in FIG. 2; FIG. 6 is a perspective view of a conventional printed board processing machine. DESCRIPTION OF SYMBOLS 3 Table 11 Main shaft unit 12 Pressure foot 14 Dust collector 17 Pipe 18 Flow rate regulator 19 Tool 20 Inlet 21 Exhaust 22 Housing 23 Main shaft 26 Intake path 27 Vent path 28 Exhaust path 29 Exhaust path W Work

Continuation of the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) B23Q 11/12 B23B 41/00 B23Q 11/00 B26F 1/16 H05K 3/00

Claims (1)

(57) [Claim 1] A table on which a work is placed, a spindle unit having a spindle for detachably holding a tool, and a dust collection device are connected to cover the tool. A pressure foot movably supported by the spindle unit is provided.The table and the spindle unit are relatively moved to hold the workpiece with the pressure foot, the tool is cut into the workpiece, and machining is performed. Is a cooling device for a spindle unit in a printed circuit board processing machine configured to suction and collect the dust by a dust collecting device, wherein a housing supporting the spindle is provided at one end thereof with a plurality of suction ports formed at predetermined intervals at a spindle. A plurality of intake paths formed toward the other end in parallel with the axis of the, and an annular ventilation path connecting the ends of the intake path,
A plurality of exhaust passages formed at predetermined intervals from the air passages toward the one end in parallel with the axis of the main shaft, and an annular exhaust passage connecting the end of each exhaust passage to an exhaust port are formed. A cooling device for a spindle unit in a printed circuit board processing machine, comprising: a spindle unit; a pipe connecting the exhaust port to the dust collecting device; and a flow regulator arranged in the middle of the pipe.