JPH0938866A - Cup-shaped grinding wheel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cup-shaped grinding wheel which can supply an abrasive liquid to a grinding wheel part at sufficient flow rate. SOLUTION: A blade part 42 heading for the opposite direction to the rotating direction of a grinding wheel 10 as moving to an outer periphery side is provided on one surface 40 of a main body part 34 and acts like a pump. Therefore, the abrasive liquid is accelerated by its press-sending force and headed to the slide-contact part between the grinding wheel part 14 and a plane to be ground 44. Accordingly, the abrasive liquid supplied from an abrasive liquid introduction hole 28 inside a peripheral wall 18 is further headed to the grinding wheel part 14 positively. Therefore, the abrasive liquid can be supplied with a sufficient flow rate to the grinding wheel part 14 by that the centrifugal force reduced by storing of the abrasive liquid inside the grinding wheel 10 is supplemented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cup-shaped grindstone, and more particularly to a technique for preventing grinding burn and welding of chips during wet grinding.

[0002]

2. Description of the Related Art A cup-shaped body having an annular peripheral wall and a bottom wall provided at one end thereof is formed into a cup shape, and is rotated about an axis to grind a grindstone portion provided at the other end surface of the peripheral wall. There is known a cup-shaped grindstone in which a work surface is ground by being brought into sliding contact with a flat surface.

[0003]

By the way, when performing wet-type surface grinding using such a cup-shaped grindstone,
The grinding fluid is emitted from the outer peripheral side of the cup-shaped grindstone toward the vicinity of the sliding contact portion between the grindstone part and the work material, but the grinding surface of the cup-shaped grindstone and the work surface of the work material are in surface contact with each other. Therefore, it is difficult to sufficiently supply the grinding liquid from the outer peripheral side of the grindstone to the sliding contact portion between the grinding surface and the work surface, and if the grinding efficiency is to be maintained, the grinding burn or There is a problem that welding of chips occurs.

On the other hand, a rotary shaft provided with a grinding fluid introduction hole and a connecting device for connecting the grinding fluid supply pipe for supplying the grinding fluid to the grinding fluid introduction hole while sealing it with a seal member are connected. It has been proposed to introduce the grinding fluid into the cup-shaped grindstone fixed to the rotary shaft through the rotary shaft by using the grinding liquid introduction device. In this way, since the grinding liquid introduced into the cup-shaped grindstone can be suitably supplied to the sliding contact portion between the grindstone and the work material by the centrifugal force accompanying the rotation of the grindstone, the grinding burn or the chips It is considered that welding and the like can be suitably prevented. However, in this case, the structure of the connecting device that connects the grinding liquid supply pipe and the rotary shaft becomes complicated, and the sealing member of the connecting device is damaged by the abrasive grains and chips mixed in the grinding liquid. Since a high-performance filter device for filtering the grinding fluid must be used in order to avoid causing the grinding fluid, the grinding fluid introduction device is disadvantageously expensive. Further, when the cup-shaped grindstone is small, the diameter of the rotating shaft for fixing the cup-shaped grinding stone is also small. Therefore, if the grinding fluid introduction hole is provided in the rotating shaft, the rigidity of the rotating shaft may be impaired.

On the other hand, for example, as described in Japanese Patent Application Laid-Open No. 6-23674, which was filed by the applicant of the present invention earlier, and having a grinding fluid introduction hole penetrating the bottom wall of the cup-shaped grindstone, It has been proposed to supply the grinding fluid to the inside of the peripheral wall through the grinding fluid introduction hole. With this configuration, the grinding fluid supplied from the outer surface side of the bottom wall to the grinding introduction hole is supplied to the contact portion between the grindstone portion and the work surface according to the action of the centrifugal force. Therefore, it is possible to suitably prevent grinding burn and welding of chips by the grinding liquid supplied into the cup-shaped grindstone without requiring the expensive grinding liquid introduction device as described above and without impairing the rigidity of the rotary shaft. It is thought to get.

However, even in this case, there is still a problem to be solved. That is, the grinding fluid supplied to the inside of the cup-shaped grindstone through the grinding fluid introduction hole, after exiting from the grinding fluid introduction hole, immediately released on the work surface, it will not be given any action force, It stays on the inner surface of the cup-shaped grindstone and becomes a flow resistance to the grinding fluid continuously supplied to the outer surface side of the bottom wall. Therefore, the problem that the force given by the centrifugal force to the grinding fluid flowing in the grinding fluid introduction hole is reduced, and the grinding fluid is not sufficiently supplied to the grindstone portion, is a problem when rotating at low speed or when using a large diameter cup-shaped grindstone It happened to.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a cup-shaped grindstone capable of supplying a grinding fluid at a sufficient flow rate to a grindstone portion.

[0008]

The gist of the present invention for achieving such an object is to provide a cup-like shape with an annular peripheral wall and a bottom wall provided at one end thereof,
A grindstone portion provided on the other end surface of the peripheral wall that has a grinding liquid introduction hole penetrating the bottom wall and is rotated around the axis while the grinding liquid is supplied to the inside of the peripheral wall through the grinding liquid introduction hole Is a cup-shaped grindstone that grinds the work surface by being brought into sliding contact with the work surface, and the inner surface side opening of the bottom wall of the grinding fluid introduction hole is separated from the inner surface of the bottom wall by a predetermined distance. And a plurality of blade portions that are fixed to the bottom wall of the main body portion and that face the bottom wall side of the main body portion toward the outer peripheral side in the direction opposite to the rotation direction. It is to include a rotary impeller standing upright at a predetermined interval.

[0009]

According to the present invention, the opening on the inner surface of the bottom wall of the grinding fluid introduction hole is covered at a predetermined distance from the inner surface of the bottom wall, and the one surface of the bottom wall is moved toward the outer peripheral side. The rotary impeller provided with a main body in which a plurality of blades directed in the direction opposite to the rotating direction is vertically provided at predetermined intervals in the circumferential direction is fixed to the bottom wall of the cup-shaped grindstone. Therefore, by being radiated from the outer side of the rotating cup-shaped grindstone toward the bottom wall, it is supplied into the grinding fluid introduction hole of the bottom wall and directed toward the inner surface side of the bottom wall, that is, the other end side of the peripheral wall. The mixed grinding fluid is supplied toward the main body of the rotary impeller that covers the bottom surface inner wall side opening of the grinding fluid introduction hole. At this time, since the blade portion provided on one surface of the bottom surface side of the main body portion acts like a pump, the grinding fluid is accelerated by its pumping force and directed toward the peripheral wall side, that is, the grindstone portion side.

Therefore, the grinding fluid is forcibly sent to the peripheral wall side by the pump action, and the centrifugal force reduced by the grinding fluid staying inside the cup-shaped grindstone is compensated for, and the grindstone portion is ground. A cup-shaped grindstone capable of supplying the liquid at a sufficient flow rate is obtained. Therefore, for example, even when a work material such as aluminum that is apt to cause clogging is ground, it is difficult to cause grinding burn or the like.

[0011] Preferably, the grindstone portion provided on the other end surface of the peripheral wall is provided with notches penetrating in the radial direction at predetermined intervals in the circumferential direction. By doing so, the grinding fluid supplied to the inside of the cup-shaped grindstone is easily discharged through the notch, so that the flow resistance of the grinding fluid is reduced and the grinding fluid is more reliably supplied to the grindstone section. Becomes

Further, preferably, the grinding fluid introducing hole is provided so as to be inclined toward the outer peripheral side toward the other end of the peripheral wall. With this configuration, since the grinding fluid introduction hole is formed obliquely with respect to the bottom wall, the grinding fluid formed between the body and the inner surface of the bottom wall is covered by the body of the rotary impeller. The passage is narrowed toward the outer peripheral side of the rotary impeller. Therefore, the grinding fluid is supplied to the grindstone portion more reliably because the jet pressure from the outer peripheral side end portion of the rotary impeller is made relatively high.

[0013]

DETAILED DESCRIPTION OF THE INVENTION An embodiment of the present invention will be described in detail below with reference to the drawings.

In FIGS. 1 and 2, a cup-shaped grindstone (hereinafter, simply referred to as a grindstone) 10 has a base metal member 12, a grindstone portion 14, and a rotary impeller 16.
The base metal member 12 includes an annular peripheral wall 18, a bottom wall 20 provided at one end of the peripheral wall 18, and a shaft portion 22 projecting from a central portion of an outer surface of the bottom wall 20 opposite to the peripheral wall 18. And a predetermined distance of about 20 to 30 mm from the shaft portion 22,
An annular projection 24 is provided on the outer surface of the bottom wall 20, and the shaft portion 22 and the annular projection 24 form an annular groove 26 around the shaft portion 22.

Both ends of the bottom wall 20 are opened at the inner surface thereof and the bottom surface of the annular groove 26.
Two grinding fluid introduction holes 28 are formed at equal intervals in the circumferential direction by, for example, drilling. This grinding fluid introduction hole 28
As shown in FIG. 1, the axial center of the peripheral wall 18 extends toward the outer peripheral side toward the other end side of the peripheral wall 18, that is, toward the inner surface of the bottom wall 20. 2 is inclined by the angle θ, and the axis of the grinding fluid introduction hole 28 is oriented toward the upstream side in the rotational direction of the grindstone 10 shown by the arrow A in FIG.
8 of the annular groove 26 is formed to be inclined by a predetermined angle φ from a plane including the center L of the bottom side opening of the annular groove 26. Above specified angle φ
Is an angle formed by a plane parallel to the axial direction of the shaft portion 22 including the axis of the grinding fluid introduction hole 28 and the above-mentioned plane, and is 90 ° in the present embodiment. The right half of FIG. 1 corresponds to a cross section taken along the line I-I in FIG. 2, but in order to facilitate understanding and show the inclination angle θ, the grinding fluid introduction hole 28 is shown in a cross section passing through the axis thereof. There is.

Further, in the grindstone portion 14, a large number of elongated grindstone members 30 are arranged at a constant interval in the circumferential direction on the other end surface (the end surface opposite to the bottom wall 20) of the peripheral wall 18 of the base metal member 12. Is provided and is integrally fixed by, for example, an adhesive. The grindstone member 30 is, for example, a so-called superabrasive grindstone in which superabrasive grains such as diamond grains or CBN (cubic boron nitride) grains are bonded by a binder such as resin, inorganic substance, metal, or plating. . In the present embodiment, the plurality of grindstone members 30 are fixed at regular intervals as described above, so that the grindstone portion 14 has a notch portion penetrating in the radial direction.

On the other hand, the rotary impeller 16 has a bottom wall 20 at the center.
Is provided with a convex portion 32 directed toward the whole, and the whole is formed in a disk shape having an outer diameter slightly smaller than the inner diameter of the peripheral wall 18.
The main body portion 34 located on the outer peripheral side of 2 from the bottom wall 20 is
The protrusions 32 are separated by a predetermined distance of about 10 to 20 mm.
Is fixed to the inner surface of the bottom wall 20 by a plurality of bolts 36. Therefore, the bottom wall 2 of the grinding fluid introduction hole 28 is
The opening portion 38 on the 0 inner surface side is covered with the main body portion 34, and a flow path of the grinding liquid is formed between the main body portion 34 and the bottom wall 20 and the peripheral wall 18. The body portion 34 is formed such that one surface 34 on the bottom wall 20 side is formed as an inclined surface that is separated from the inner surface of the bottom wall 20 toward the outer peripheral side, so that the wall thickness is reduced toward the outer peripheral side. .

Further, on one surface 40 of the main body 34 on the bottom wall 20 side, as shown in FIG. 3 showing only the rotary impeller 16 viewed from above in FIG. To the outer peripheral side of the rotary impeller 16 so as to face in the direction opposite to the rotating direction of the grindstone 10 shown by the arrow A in the figure, in other words, the inclination angle with respect to the radial direction becomes larger at the outer peripheral side. A plurality of pieces (8 in this embodiment)
Book) blade portion 42 is provided.

The grindstone 10 configured as described above is used, for example, in a vertical grinding machine, the shaft portion 22 is fixed to a rotary shaft (not shown), and the grindstone portion 14 is rotated while being driven by the rotary shaft. The tip surface is brought into sliding contact with the work plane 44 of the work material, so that the work plane 44 is ground. During such grinding, the grinding fluid is discharged from the nozzle 46 disposed above the grindstone 10 in FIG. 1 into the annular groove 26.
The grinding fluid supplied to the inside of the No. 6 is supplied to one surface 40 of the main body 34 through the grinding fluid introduction hole 28, and further passes through the flow path formed between the bottom wall 20 and the peripheral wall 18 and the rotary impeller 16. And is supplied to the sliding contact portion between the grinding surface of the grindstone portion 14 and the work surface 44 of the work material.

By the way, as shown in FIG. 2, the grinding fluid in the grinding fluid introduction hole 28 is rotated by the rotation of the grindstone 10 as shown in FIG.
The centrifugal force f _c acts in the normal direction of the outer periphery of the grindstone 10 and the inertial force f _i acts in the tangential direction. As shown in FIGS. 1 and 2, the grinding fluid introducing hole 28 is inclined toward the inner surface of the bottom wall 20 toward the outer peripheral side of the bottom wall 20, and is directed toward the inner surface of the bottom wall 20 by the arrow A. Since the grindstone 10 is formed so as to be inclined toward the upstream side in the rotation direction of the grindstone 10, the force f
The axial component forces of _c and f _i of the grinding fluid introduction hole 28 are both directed in the direction of arrow B, that is, toward the opening 38 side. Therefore, the grinding fluid supplied into the annular groove 26 is positively supplied onto the one surface 40 of the main body portion 34 by the action of the resultant force of those component forces generated according to the inclination angle of the grinding fluid introduction hole 28. It will be.

On the other hand, on one surface 40 of the main body portion 34, there is provided a blade portion 42 which is curved in a direction opposite to the rotating direction of the grindstone 10 toward the outer peripheral side.
The grinding fluid supplied to the rotor 0 is accelerated toward the outer peripheral side of the rotary impeller 16, that is, the peripheral wall 18 by the pump action. That is, the grinding fluid receives a thrust toward the outer peripheral side in accordance with the relative rotation with the rotary impeller 16. As a result, the grinding liquid is positively supplied to the sliding contact portion between the grinding surface of the grindstone portion 14 and the work surface 44 of the work material.

That is, in this embodiment, as described above, the blade portion 42 is provided on the one surface 40 of the main body portion 34 so as to be curved in the direction opposite to the rotation direction of the grindstone 10 toward the outer peripheral side. In order to act like a pump, the grinding fluid is accelerated by its pumping force and directed toward the sliding contact portion between the grindstone portion 14 and the work surface 44. Therefore, the grinding fluid supplied from the grinding fluid introduction hole 28 to the inner side of the peripheral wall 18 is further positively directed to the grindstone portion 14, and the centrifugal force reduced by the grinding fluid staying inside the grindstone 10. That is, the whetstone 10 that can supply the grinding fluid to the whetstone portion 14 at a sufficient flow rate is obtained.

Moreover, since the grinding fluid introducing hole 28 is provided in the bottom wall 20 in an inclined manner, it is covered by the main body portion 34 of the rotary impeller 16 so that the one surface 40 of the main body portion 34 is covered.
The flow path of the grinding fluid formed between the inner surface of the bottom wall 20 and the inner wall of the bottom wall 20 is narrowed toward the outer peripheral side of the rotary impeller 16.
Therefore, the pressure of the grinding fluid ejected from the outer peripheral side end of the rotary impeller 16 is made relatively high, so that the grinding stone portion 1 can be more reliably discharged.
4.

Further, the grindstone portion 14 provided on the other end surface of the peripheral wall 18 is supplied to the inner side of the grindstone 10 because the grindstone members 30 are fixed at a constant interval in the circumferential direction. The grinding fluid is easily discharged from the gap formed between the grindstone members 30. Therefore, the accumulation of the grinding fluid in the grindstone 10 and the generation of the flow resistance are reduced, and the grinding fluid is more reliably supplied to the grindstone portion 14.

While the embodiment of the present invention has been described with reference to the drawings, the present invention can be applied to other embodiments.

For example, in the above-mentioned embodiment, the grinding liquid introduction hole 2
8 is inclined toward the outer peripheral side as it goes to the tip side of the peripheral wall 18 and toward the upstream side in the rotation direction of the grindstone 10, but to the tip side of the peripheral wall 18 without inclination in the rotation direction. Even when the grindstone 10 is formed so as to be inclined outward in the radial direction as it goes, the effect of the present invention can be similarly obtained. Further, the inclination angles θ and φ of the grinding fluid introducing hole 28 are not limited to the angles shown in the embodiment, and for example, θ is in the range of 20 to 50 ° and φ is 60 to 60 °.
It is changed appropriately within the range of 120 °.

In the above embodiment, the grinding fluid supplied into the annular groove 26 is introduced into the grindstone 10 through the grinding fluid introducing hole 28.
By acting as a pool of grinding fluid, the nozzle 46
The grinding fluid discharged from the grindstone toward the grindstone 10 is efficiently guided to the grinding fluid introduction hole 28, and the effect of the present invention can be obtained even if the grinding fluid is not necessarily provided.

The cup-shaped grindstone 10 of the above embodiment is
Although it is composed of the base metal member 12 and the grindstone portion 14 containing abrasive grains, it may be composed entirely of abrasive grains.

Further, in the above-described embodiment, the body portion 34 of the rotary impeller 16 is provided with eight curved blade portions 42, but the shape and the number of the blade portions 42 provide a pumping action. The range is appropriately changed. For example, it is effective that the shape corresponds to a streamline such as an involute curve or a logarithmic spiral, but a similar effect can be expected even if it is a diagonal line.
In addition, it is desirable that the number is 4 or more from the viewpoint of effect and economy.

Further, although the grindstone member 14 of the above-mentioned embodiment is composed of a superabrasive grindstone, it may be composed of silicon carbide abrasive grains or fused alumina abrasive grains other than the superabrasive grains.

Further, in the embodiment, the grindstone portion 14 is fixed to the plurality of grindstone members 30 at predetermined intervals to form notches at predetermined intervals in the circumferential direction. The grindstone portion 14 may be integrally formed in an annular shape and may be provided by removing a part in the axial direction at predetermined intervals in the circumferential direction. That is, the notch does not necessarily have to be formed so that a gap is created between the work surface and the grindstone 10, and is formed on the outer peripheral surface of the peripheral wall 18 near the sliding contact portion between the grindstone portion 14 and the work surface 44. If so, the same effect as that of the embodiment can be obtained. Furthermore, the effect of the present invention can be obtained even if the notch is not necessarily provided.

Further, in the above embodiment, the four grinding liquid introduction holes 28 are provided at equal intervals, but the grinding liquid introduction holes 28 are
May be provided at unequal intervals, and if one or more are provided as long as the dynamic balance is maintained, the temporary effect of the present invention can be obtained. Further, the openings 38 may be provided so as to be arranged in each of the spaces formed by the blade portions 42 according to the number of the blade portions 42.

Further, in the above-mentioned embodiment, the cup-shaped grindstone 10 is attached to the vertical grinding machine, but it is needless to say that the effect of the present invention can be obtained even when it is attached to the horizontal grinding machine. .

The above description is merely one embodiment of the present invention, and the present invention can be variously modified without departing from the spirit thereof.

[Brief description of drawings]

1 is a front view of a cup-shaped grindstone of the present invention, and FIG.
FIG. 3 is a view showing a cross section corresponding to a cross section taken along line I-I of FIG.

2 is a plan view of the cup-shaped grindstone of FIG. 1. FIG.

FIG. 3 is a diagram showing a state in which only the rotary wheel of the cup-shaped grindstone of FIG. 1 is viewed from above.

[Description of sign]

 10: Cup-shaped grindstone 14: Grindstone part 16: Rotor wheel 18: Peripheral wall 20: Bottom wall 26: Annular groove 28: Grinding liquid introduction hole 34: Main body part 38: Opening part 42: Blade part 44: Work plane

Claims (2)

[Claims] 1. A cup-shaped body having an annular peripheral wall and a bottom wall provided at one end thereof, and having a grinding liquid introducing hole penetrating the bottom wall, and passing through the grinding liquid introducing hole, the peripheral wall of the peripheral wall is formed. A cup-shaped grindstone that grinds the work surface by rotating the work piece around the axis while supplying the grinding fluid to the inside and slidingly contacting the grindstone portion provided on the other end surface of the peripheral wall with the work surface. A main body is provided to cover the inner surface side opening of the bottom wall of the grinding fluid introduction hole with a predetermined distance from the inner surface of the bottom wall, the main body being fixed to the bottom wall, and the bottom of the main body. A cup-shaped grindstone, comprising a rotary impeller in which a plurality of blade portions, which face in a direction opposite to the direction of rotation toward the outer peripheral side on one wall side, are erected at predetermined intervals in the circumferential direction. 2. The cup-shaped grindstone according to claim 1, wherein the grindstone portion provided on the other end surface of the peripheral wall is provided with notch portions penetrating in the radial direction at predetermined intervals in the circumferential direction.