JPS61152367A - Laser dressing device for cbn grindstone - Google Patents

Abstract

PURPOSE:To dress an on-machine grindstone in a short time, by supplying reactive gas on the grinding grain layer surface of the grindstone, focusing a laser beam on the stone and scanning the beam spot along the grindstone width. CONSTITUTION:While a laser beam 13 emitted from a laser oscillator 14 is focused into a spot (A) on the loading layer of grinding grain layer of the grindstone attached to the rotation axis 2 of CBN (cubic boron nitride) grinding machine through a reflecting mirror 15 and a lens 16, reactive gas is supplied to the beam spot (A) through a nozzle 22. Loading metal at the beam spot (A) is thereby melted and blown away by the gas from the stone. The dressing is carried out by scanning the beam spot (A) along the width (W) of the grindstone 10, while rotating the grindstone 10. With this constitution, the on-machine dressing of the grindstone is carried out in a short time.

Description

Detailed Description of the Invention (a) Purpose of the Invention [Industrial Field of Application] The present invention relates to a laser dressing device, and more specifically, to a laser dressing device that is applied to an abrasive layer of a CBN grindstone or the like used in grinding, which is a type of machining. This invention relates to a device for melting and removing clogged metal by irradiating laser light.

[Prior Art 1] It is well known that CBN grinding wheels are used for grinding hard materials such as hardened steel. As shown in FIG. 3, the CBN grinding wheel 10 has a disk shape and is rotatably fixed to one end of the rotating shaft 2 with a nut 3. Rotating axis 2
Rotation is transmitted to the drive motor 5, the belt 19, and the grindstone rotation mechanism 4. The outer peripheral part of the CBN grinding wheel 10 is an abrasive grain layer 6, and this part is made of CBN as shown in FIG.
(cubic boron nitride) micro abrasive grains 7 and a metal binder 8 are mixed and solidified by sintering.

Grinding is performed by rotating the CBN grinding wheel 10 at high speed and bringing the abrasive grain layer 6, which is the outer periphery thereof, into contact with the surface of the workpiece 12 rotating at low speed via the center 11.

If the grinding process is continued, a layer 9 clogged with chips is gradually formed on the surface layer of the abrasive grains 16, and the grinding performance deteriorates, so dressing is required to remove the layer 9 clogged.

Conventionally, electrolytic processing has been mainly used for dressing CBN grinding wheels. The electrolytic processing method uses an electrode and an electrolytic solution to dissolve and remove the clogging layer 9, but C
The operation is troublesome, such as having to remove the BN grinding wheel 10 from the rotating shaft 2, and since it is electrochemically dissolved, it takes time to comb the clogged layer deep. Therefore, there is a problem that the time required for dressing becomes longer and processing efficiency decreases.

[Problems to be Solved by the Invention] This invention was made in view of the above-mentioned circumstances, and it is easy to handle and can be carried out on-machine and in a short time without removing the grinding wheel from the rotating shaft of the grinding machine. The purpose of the present invention is to provide a dressing device that can improve processing efficiency.

(B) Structure of the Invention [Means for Solving the Problem] Corresponding to this purpose, a laser dressing device for a CBN grinding wheel includes a laser oscillator that outputs a laser beam, and a laser dressing device that uses the laser beam to prevent clogging of the CBN grinding wheel. an optical device that focuses light on a focal point of the layer; a scanning mechanism capable of scanning the focal point across the width of the CBN grinding wheel; The invention is characterized by comprising a gas supply device capable of supplying active gas to the active parts.

Hereinafter, details of the present invention will be explained with reference to the drawings showing one embodiment.

In FIG. 1, 1 is a laser dressing device, and the laser dressing device ali1 has a laser oscillator 14 as a laser light source and an optical device 17, both of which are connected to a conduit 18.
are tied together. The optical device 17 reflects the laser beam 13 output from the laser oscillator 14 with a reflecting mirror 15, and then
A scanning mechanism (not shown) that can focus light on the surface of the abrasive grain layer 6 of the CBN grinding wheel 10 with a CI or ln 3e lens 16 and scan the focused point A over the width W of the CBN grinding wheel 10. It is equipped with

The laser dressing device 1 also includes a gas supply device 21 capable of supplying an active gas such as oxygen to the convergence point A of the laser beam on the abrasive grain layer 6, and an injection nozzle connected to the gas supply device 21. 22 opens near the condensing point A.

[Function] In the laser dressing device 1 configured as described above, the laser beam 13 output from the laser oscillator 14 enters the optical device 17 through the conduit 18, the optical path is changed by reflection @15, and the laser beam 13 is outputted from the laser oscillator 14. The light is focused on one point A on the clogging layer 9 on the abrasive grains 116 of the CBN grinding wheel 10. Therefore, high-density energy is concentrated at the focal point A. At the same time, active gas such as oxygen supplied by the gas supply device 21 is injected from the injection nozzle 22 to the condensing point A, so the metal forming the clogging layer at the converging point A is easily melted. The removed metal is blown off and removed from the surface of the abrasive grain layer 6 by the gas flow.

[Example] ■Experiment When a CBN grinding wheel under conditions (A> below) was laser dressed using a dressing device under conditions (B), the required time was a little over 4 minutes as shown in ■.

■ Calculating the time required for laser dressing The time required for the laser light to go around the outer circumference of the CBN grinding wheel is 400-yr (mm> / 100111+11/
seconds) = 12.6 (seconds) The time required to scan the entire width of the grinding wheel 2Qmm is 12.6 (seconds) x (20( mn+) /1 (mm
) - 4 minutes 12 seconds Same (A>) The time required to dress a CBN grinding wheel using the conventional electrolytic processing method is 15 minutes, so even if you compare only the processing time, it is less than 1/3 Become.

Note that the laser beam scanning speed needs to be adjusted depending on the magnitude of the laser beam output and the depth of the clogged layer, but it is not affected by the material of the clog, that is, the material of the workpiece. The depth of the clogged layer is usually 0.51111 or less, and in this case, if the laser output is 0.5 to 1 and the OKW, CBN grinding wheel rotation speed is 300 mai/sec, dressing will be completed in about 1.5 minutes. .

(c) Effects of the Invention As is clear from the above explanation, the present invention is easy to handle and can be dressed on-machine in a short time without removing the CBN grinding wheel from the grinding machine. A dressing device that can improve processing efficiency can be obtained.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of the configuration of a laser dressing device for a CBN grinding wheel, FIG. 2 is a sectional view of an abrasive grain layer of the CBN grinding wheel, and FIG. 3 is an explanatory diagram showing how the CBN grinding wheel is used. 1... Laser dressing device 2... Rotating shaft 3
... Nut 4 ... Grinding wheel rotation mechanism 5 ... Drive motor 6 ... Abrasive grain layer 7 ... CBN abrasive grain
8... Metallic binder 9... Clogging layer 10
... CBN grinding wheel 11... Center 12.
...Workpiece 13...Laser beam 14...Laser oscillator 15...Reflector 16...Lens 1
7... Optical device 18... Conduit 19... Belt 21... Gas supply device 22... Injection nozzle Fig. 1 + 7 13 18 14 1 Fig. 2

Claims (1)

[Claims] a laser oscillator that outputs a laser beam; and a laser oscillator that focuses the laser beam on a focal point on the surface of an abrasive layer of a metal bonded CBN grinding magnet and scans the focal point over the width of the CBN grinding wheel. 1. A laser dressing device for a CBN grinding wheel, comprising: an optical device for obtaining the laser beam, and a gas supply device capable of supplying an active gas to a portion of the abrasive grain layer of the CBN grinding wheel where the laser beam is focused.