JPS5834255B2 - Grinding wheel dressing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for dressing a grinding wheel using a hard material such as cubic boron nitride as abrasive grains, and its purpose is to keep the grinding wheel in good condition and with high precision. It is to be able to make dressing.

Conventionally, when dressing a grinding wheel whose abrasive grains are made of a hard material such as cubic boron nitride, this grinding wheel and a dressing wheel made of hard metal such as hardened steel are placed opposite each other, and a free abrasive for dressing is placed between the two. Forming a gap with an appropriate size (approximately 1/2 of the average free abrasive grain diameter) smaller than the outer diameter of the grains,
A dressing liquid mixed with the free abrasive grains is supplied to this gap, and the bond holding the abrasive grains is scraped off by the free abrasive grains to dress the grinding wheel with the backup of the dressing wheel.

However, since there are variations in the size of the free abrasive grains mixed into the dressing liquid, free abrasive grains larger than the average diameter may be supplied to the gap, or free abrasive grains may be supplied in a state where they overlap each other, As a result, the pound that holds the abrasive grains of the grinding wheel is scraped off more than necessary by these loose abrasive grains, which may result in insufficient retention of the abrasive grains or may even cause the abrasive grains to fall off, which may cause the grinding wheel to become in good condition and There was a drawback that highly accurate dressing could not be performed.

The present invention has been made in order to eliminate these conventional drawbacks, and is characterized in that the dressing wheel is supported by an elastic member so as to be displaceable in the radial direction.

Embodiments of the present invention will be described below based on the drawings.

First, a grinding apparatus equipped with a dressing device of the present invention will be described. In FIG. 1, reference numeral 1 denotes a base, and a grindstone head 2 is slidably mounted on this base 1.

Reference numeral 3 denotes a pulse motor mounted on the base 1 to feed the grindstone head 2, and the whetstone head 2 is moved forward and backward by the operation G of an unillustrated feed screw mechanism connected to the pulse motor 3.

Reference numeral 4 denotes a grinding wheel in which abrasive grains made of a hard material such as cubic boron nitride are fixed to the outer peripheral surface of an aluminum disk in a layered manner, and this grinding wheel 4 is rotationally driven by a drive motor 5 fixed to the grinding wheel head 2 It looks like this.

Further, a table 6 is mounted on the base 1 so as to be slidable in the axial direction of the grinding wheel 4, and is moved by a fluid pressure cylinder device of a circuit.

A headstock 7 and a tailstock 8 that rotatably support a workpiece W are placed on this table 6, and the workpiece W is moved to face the grinding wheel 4 by the movement of the table 6, and the grinding wheel 2 is moved forward. The movement causes grinding by the grinding wheel 4.

Next, the dressing device installed in the grinding device will be explained with reference to FIGS. 2 to 4.

First, 10 is a dressing wheel for dressing the grinding wheel 4, and is made of hard metal such as carbon steel or hardened steel.

This dressing wheel 10 is formed into an annular body, and can be displaced in the radial direction by an elastic member 12 made of elastic rubber such as urethane rubber or silicone rubber, which is inserted in an annular shape between it and the rotating disk body 11. Supported.

Further, a truing wheel 13 for truing the grinding wheel 4 before tracing the grinding wheel 4 is integrally connected to the rotating disk body 11.

This truing wheel 13 is a metal disc with a diamond abrasive grain layer fixed to the outer peripheral surface thereof.

The dressing car 10 is this truing car 13.
There is a gap t between the grinding wheel 4 and the grinding wheel 4, which has an appropriate size (approximately 1/2 of the average diameter of the free abrasive grains) smaller than the outer diameter of free abrasive grains 20 for dressing, which will be described later.
2 in diameter from the truing wheel 13 so that
It is smaller by t.

Reference numeral 14 denotes a support stand slidably mounted on a base 15 fixed to the table 6, on which the rotary disk body 11 is rotatably supported, and a drive fixed on the support stand 14. The motor 16 rotates the grinding wheel 4 in a direction opposite to the rotating direction of the grinding wheel 4 so as to reduce the peripheral speed relative to the grinding wheel 4 .

Reference numeral 17 denotes a feed screw shaft which is rotatably supported by the base 15 and screwed into the support stand 14. The dressing wheel 10 and the truing wheel 13 are moved to a predetermined position by adjusting the movement of the support stand 14 by rotation of the feed screw shaft 17. preset in position.

Reference numeral 18 denotes a nozzle for supplying a dressing liquid to the gap t. This nozzle 18 is mounted on the support base 14 and connected to a tank 19 in which the dressing liquid is stored via a pump P.

For example, the dressing liquid may be a grinding liquid of 101 to 20 free abrasive particles such as alumina or silicon carbide (average diameter approximately 1
00μ) at a ratio of 500g.

21 is a stirring blade that mixes the grinding fluid and the free abrasive grains 20;
It is rotated by a motor 22 attached to the tank 19.

Next, the operation in the above embodiment will be explained.

When truing a grinding wheel 4 whose sharpness has deteriorated due to repeated grinding of a workpiece, first, in order to truing the grinding wheel 4, the grinding wheel head 2 is advanced by the operation of the pulse motor 3, and the truing wheel 13 is moved forward by the operation of the pulse motor 3. 4 by the truing amount, and then move the table 6 to the right in FIG. 1 by a fluid pressure cylinder device,
The outer peripheral surface of the grinding wheel 4 is trued by a truing wheel 13.

When the dressing wheel 10 faces the grinding wheel 4, the movement of the table 6 is stopped, and the above-mentioned gap t is formed between the two wheels 4 and 10.

Thereafter, the pump P is activated and the dressing liquid is supplied from the nozzle 18 to the gap t.

As a result, the free abrasive grains 20 in the dressing liquid are backed up by the dressing wheel 10 while passing through the gap t, and bite into and scrape off the bond holding the abrasive grains of the grinding wheel 4, causing the abrasive grains to protrude from the bond. dressing the grinding wheel 4.

During this dressing, for example, if free abrasive grains 20 larger than the average diameter pass through the gap t, or if free abrasive grains 20
When the dressing wheels 10 pass through the gap t in an overlapping state, the dressing wheel 10 is slightly retreated in the radial direction due to the elastic deformation of the elastic member 12 and adapts well to the state of the loose abrasive grains 20.

Therefore, these free abrasive grains 20 prevent the bond holding the abrasive grains of the grinding wheel 4 from being scraped off more than necessary, and as a result, there is no possibility of unstable abrasive grain retention or drop-off of the abrasive grains.

In the embodiment described above, dressing is performed by forming a gap t between the grinding wheel 4 and the dressing wheel 10, but since the dressing wheel 10 is movable in the radial direction as described above, the gap t is made small. Alternatively, dressing may be carried out by bringing the dressing wheel 10 into contact with the grinding wheel 4, which allows flexibility in the size of the gap t.

Further, in the above embodiment, elastic rubber is used as the elastic member 12, but foamed plastic such as polyurethane or polyolefin may also be used.

Further, in the above embodiment, the dressing wheel 10 is supported so as to be displaceable in the radial direction by the elastic member 12 inserted between the dressing wheel 10 and the rotating disk body 11, but the dressing wheel 10 and the rotating disk body 11 are integrally formed. , this integrated dressing wheel 10 is rotatably supported on a sliding table that is slidably mounted on a supporting table 14, and this sliding table is attached to the grinding wheel 4 by a spring or the like on the supporting table 14. It may also be supported so as to be elastically displaceable.

In this case, the truing wheel 13 is the rotating disk body 11.
It is separated from and rotatably supported on a support stand 14.

As detailed above, the present invention provides an apparatus in which free abrasive grains are supplied between a grinding wheel and a dressing wheel that face each other, and the grinding wheel is dressed with the free abrasive grains.
Since the dressing wheel is supported by an elastic member so that it can be displaced in the radial direction, loose abrasive grains larger than the average diameter or overlapping each other may be supplied between the grinding wheel and the dressing wheel during dressing. ,
These free abrasive grains prevent the bond holding the abrasive grains of the grinding wheel from being scraped off more than necessary, so that the grinding wheel can be dressed in good condition and with high precision.

Furthermore, during dressing, the above-mentioned appropriate gap may be provided between the grinding wheel and the dressing wheel, or the two wheels may be brought into contact with each other, so that the accuracy of the gap between the two wheels can be ensured accurately. The advantage is that you don't have to.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing a grinding device equipped with a grinding wheel dressing device according to the present invention, and FIG.
3 is an enlarged sectional view taken along the line II, FIG. 3 is a sectional view of the dressing wheel shown in FIG. 2, and FIG. 4 is an enlarged sectional view taken along the line ■-■ in FIG. 4... Grinding wheel, 10... Dressing wheel, 11... Rotating disc body, 12...
- Elastic member, 20... loose abrasive grains.

Claims (1)

[Scope of Claims] 1. A dressing wheel is placed opposite to a grinding wheel whose abrasive grains are made of a hard material such as cubic boron nitride, and free abrasive grains for dressing are supplied between the two, so that the abrasive grains are removed by the grinding wheel. In a dressing device that performs dressing by
A dressing device for a grinding wheel, characterized in that the dressing wheel is supported by an elastic member so as to be displaceable in the radial direction. 2. The grindstone according to claim 1, wherein the dressing wheel is an annular body, and the elastic member is annularly inserted between the dressing wheel and a rotating disk body that supports the dressing wheel. Car dressing equipment.