JP2924305B2 - Water-permeable cup type whetstone - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cup-type grindstone used for surface grinding of various workpieces, and more particularly to an improvement for preventing clogging and overheating of an abrasive layer.

[0002]

2. Description of the Related Art A general cup-type grindstone is one in which an abrasive layer having a constant thickness is formed on an end face of a peripheral wall portion of a cup-shaped base (grinding base), and a center hole of the base is ground. The work material is ground at the end surface of the abrasive grain layer by fixing and rotating the rotating shaft of the board.

[0003]

However, in the cup-type grindstone as described above, it is inevitable that the abrasive layer is clogged with the grinding, and the grinder is stopped every time a fixed amount of work material is processed. Then, dressing must be performed to cure the clogging of the abrasive grain layer, which has the disadvantage of requiring much time. In addition, when heavy grinding is performed, problems such as overheating of the abrasive grain layer and seizure of the work material may occur.

[0004]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and has a cup-shaped grindstone substrate and a porous abrasive having water permeability provided on an end face of a peripheral wall portion of the grindstone substrate. And a cavity is formed inside the grindstone base, and an opening communicating with the cavity is formed on the outer surface of the grindstone base. Inside the opening, an external part is formed as the grindstone base rotates. A suction blade structure for sucking air and introducing the air into the cavity, further opening the end surface of the grinding wheel base which communicates with the cavity and joining the grinding fluid supplied to the inside of the grinding wheel base along the way with the air. The gas passage leading out from the end face is formed.

[0005] A grinding fluid dispersion layer having water permeability may be provided between the end face of the grinding wheel base and the porous abrasive layer.

[0006]

In the water-permeable cup-type grindstone of the present invention, as the grindstone rotates, the suction blade structure provided on the outer surface of the grindstone base sucks in external air and introduces it into the cavity. The introduced air is then led out from the end face of the grinding wheel base through the gas passage.On the way, the grinding fluid supplied to the inside of the grinding wheel through the rotating shaft merges with the air, and along with the air, the grinding fluid flows from the end face of the grinding wheel base. It is supplied to the porous abrasive layer. Since the supplied grinding fluid and air travel while dispersing inside the porous abrasive layer and are released from the grinding surface, the porous abrasive layer is cooled by the grinding fluid and air in the process, preventing overheating. In addition, swarf adhering to the ground surface is washed away, so that clogging can be prevented. Furthermore, since a sufficient amount of grinding fluid is forcibly supplied to the grinding point, a good lubrication state is formed by the grinding fluid, the grinding resistance can be reduced, and heavy grinding such as deep cutting can be performed. And a good finished surface roughness is obtained.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a water-permeable cup type grindstone according to the present invention will be described in detail. 1 to 3 show one embodiment of the present invention. In the drawings, reference numeral 1 denotes a cup-shaped grinding wheel base, 2
Is a grinding fluid dispersion layer fixed to the peripheral wall end face of the grinding wheel base 1;
Reference numeral 4 denotes a porous abrasive layer fixed to the end surface of the grinding liquid dispersion layer 2.

[0008] Inside the shoulder portion of the grinding wheel base 1, the grinding wheel base 1
An annular cavity 6 extending over the entire circumference is formed, and an opening 8 communicating with the cavity 6 is formed in the outer peripheral surface of the shoulder in an annular shape over the entire circumference. Further, in the opening 8, a large number of plate-like blades 10 are formed integrally with the grindstone base 1 at regular intervals in the circumferential direction.

As shown in FIG. 3, the blades 10 are all inclined at a fixed angle with respect to the tangential direction of the outer peripheral surface of the peripheral wall portion. The grinding fluid supplied inside is sucked and forcedly introduced into the cavity 6.

Further, inside the grindstone base 1, a gas introduction passage (part of a gas passage) 12 extending from the cavity 6 to the inner surface of the shoulder.
Are formed at regular intervals in the circumferential direction. Further, in the peripheral wall portion of the grindstone base 1, a gas outlet path (a part of a gas passage) 14 having one end opened on the inner peripheral surface of the grindstone base 1 and the other end opened on the end surface of the peripheral wall portion is shown in FIG. Thus, a large number are formed at regular intervals in the circumferential direction. The opening position of the gas outlet passage 14 on the inner peripheral surface of the peripheral wall portion is set to a position at which the grinding fluid ejected from the grinding fluid ejection hole H of the rotating shaft S is blown.

The grinding fluid dispersion layer 2 in this embodiment is, as shown in FIG. 4, a metal layer having a constant thickness in which continuous air holes 30 having a three-dimensional network structure are formed in a non-directional manner.
Each of the communication holes 30 is open on both sides of the grinding fluid dispersion layer 2, and a fluid can flow through the communication holes 30 in a non-directional manner.

The inner wall surface of each communication hole 30 is formed of a heat-resistant coating 32 over the entire surface. This heat-resistant coating 32
Are relatively high melting point metals and alloys such as Ni, Co, Cu, etc.
Alternatively, it is formed of ceramics such as alumina and magnesia.

Around each heat-resistant coating 32, a heat-resistant coating 32
The filling metal (or resin) 34 having a lower melting point is filled over the entire area, and the strength is secured. Examples of the material of the filling metal 34 include an Al alloy, a Sn alloy, and a Cu alloy, and an Al alloy is particularly preferable in terms of melting point and weight reduction. Further, as the filling resin 34, a resin such as polyimide, epoxy, or phenol can be used.

The heat-resistant coating 32 is made of Ni or Ni.
When the filler metal 34 is made of a metal that is easily soluble in an acid such as an alloy and the like, and the filling metal 34 is made of a metal that is hardly soluble in an acid such as an Al alloy, only the heat-resistant coating 32 is melted by passing nitric acid or the like into the communicating holes 30. It may be removed and the inner diameter of the continuous ventilation hole 30 may be enlarged.

On the other hand, the porous abrasive layer 4 is a layer in which superabrasives 36 such as diamond or CBN are dispersed and fixed in a metal plating phase 38 such as Ni, Co, or Cu. The average particle size and the abrasive content of the superabrasive grains 36 and the thickness of the porous abrasive layer 4 are appropriately determined depending on the use of the grindstone.

A vertical liquid supply hole 4 is provided inside the porous abrasive layer 4.
A large number of zeros are formed at intervals, and one end of each liquid supply hole 40 communicates with each of the communication vents 30, and the other end is opened on the surface (ground surface) of the porous abrasive layer 4. .

In order to form the above-mentioned grinding fluid dispersion layer 2 and porous abrasive grain layer 4, the following method is possible. First, a resin porous body 42 as shown in FIG. 5 is prepared. The resin porous body 42 is obtained by highly foaming a resin using a foaming agent, and each fiber has a nondirectional three-dimensional network structure.

Next, the heat-resistant coating 32 is formed to have a substantially constant thickness over the entire surface of the fiber of the resin porous body 42. When the heat-resistant coating 32 is formed of a high-melting-point metal such as Ni, Co, or Cu or an alloy thereof, the electroless plating method is easy.

On the other hand, when ceramics such as alumina, magnesia, and calcia are used as the heat-resistant coating 32, these fine powders are dispersed in water glass or the like, and this dispersion is applied to a resin porous body 42. Dry and solidify. After repeating this operation, by sintering, the resin porous body 42 is thermally decomposed and removed.
Is formed.

The resin porous body 42 having the heat-resistant coating 32 formed thereon
Then, the molten metal of the filling metal 34 is filled. When the molten metal is sufficiently solidified, both sides of this plate material are ground, and the end of the continuous ventilation hole 30 is opened to form the grinding liquid dispersion layer 2.

Next, the grinding liquid dispersion layer 2 is immersed in a plating solution, and a porous abrasive layer 4 is formed on the surface of the grinding liquid dispersion layer 2 while flowing air at a constant pressure from the back side. Then, during plating, air bubbles are always generated from the openings of the respective communication holes 30, so that metal deposition is prevented in the passage of the air bubbles and the liquid supply holes 40 are formed.

In order to use the water-permeable cup type grindstone having the above structure, the grindstone base 1 is fixed to a rotating shaft S having a liquid supply means with a nut N as shown in FIG. A liquid supply path K is formed at the center of the rotation axis S, and a flange portion F disposed inside the grindstone base 1 extends radially from the liquid supply path K and has an opening on the outer peripheral surface of the flange portion F. A large number of grinding fluid ejection holes H are formed.

Next, the rotating shaft S is rotated, and while the grinding fluid is ejected from the grinding fluid ejection hole H through the liquid supply passage K, the abrasive layer 4 is applied to the work material and ground. Then, as the grindstone base 1 rotates, the blade 10 sucks in external air and / or grinding fluid, and is supplied to the inside of the grindstone base 1 through the cavity 6 and the gas introduction path 12. If the porous abrasive layer 4 is in contact with the workpiece over its entire circumference, or if there is only a small gap between them, the inside of the grinding wheel base 1 is pressurized and air is supplied to the gas outlet 14. Inflow. At this time, a part of the grinding fluid ejected from the grinding fluid ejection hole H through the rotating shaft S merges with the air, flows into the gas outlet path 14, and is supplied to the grinding fluid dispersion layer 2. For this reason, the grinding fluid and the air spread in the plane direction through the respective communication holes 30 of the dispersion layer 2,
Further, it is introduced into the porous abrasive layer 4 and discharged from the ground surface through the liquid supply hole 40.

In this process, the porous abrasive layer 4 is cooled by the grinding fluid and air, so that overheating is prevented, and chips adhering to the ground surface are constantly washed away, thereby preventing clogging. Therefore, the number of times of stopping the grinding for eliminating the clogging may be reduced, the seizure of the abrasive layer 4 with the work material due to overheating does not occur, and the reduction of the grinding accuracy due to the thermal expansion of the abrasive layer 4 is also prevented. be able to. In addition, since a sufficient amount of grinding fluid is forcibly supplied to the grinding point, a good lubrication state is formed by the grinding fluid, the grinding resistance can be reduced, and heavy grinding such as deep cutting can be performed. And the finished surface roughness of the work material can be improved.

In this embodiment, the individual liquid supply holes 40
Is constant over the thickness direction of the porous abrasive layer 4, so that the diameter of the liquid supply hole 40 does not change even if the porous abrasive layer 4 wears out during grinding. For this reason, there is no possibility that the flow rate of the liquid supply changes and affects the grinding conditions.

Further, since the continuous ventilation holes 30 having a three-dimensional network structure are formed throughout the inside of the grinding fluid dispersion layer 2, the grinding fluid dispersion layer 2 has a cushioning property. Therefore, the contact of the porous abrasive layer 4 with the work material is soft, and the super abrasive grains 36 are prevented from excessively biting into the work material, so that the finished surface roughness can be improved.

The porous abrasive layer 4 may have a structure as shown in FIG. 6 or FIG.

In the example of FIG. 6, the metal plating layer 38 is dispersed while the abrasive grains 36 are dispersed in the resin porous body 42 shown in FIG.
Is deposited and filled in the resin porous body 42, and then the whole is heated to remove the porous body 42, and the communicating vent 30 is formed in the trace of the removal. In this example, the abrasive layer 4
Since the continuous ventilation holes 30 having a three-dimensional network structure are formed in a non-directional manner throughout the inside, the abrasive layer 4 is formed from the inner peripheral side.
Is supplied to the grinding surface while being dispersed inside the abrasive layer 4. Therefore, it is not necessary to provide the grinding fluid dispersion layer 2 as in the above embodiment, and it may be formed directly on the outer peripheral surface of the grinding wheel base 1 as shown in FIG.

On the other hand, in the example of FIG. 7, after forming a metal coating layer on the surface of the resin porous body 42 by electroless plating, the metal coating layer is connected to a cathode to disperse the abrasive grains 36. The abrasive grains 36 are fixed to the surface of each metal coating layer by a metal plating phase 38 by applying an electric current between the anode and the anode arranged opposite to each other in the plating solution to perform electrolytic plating. According to this example, since the continuous ventilation holes 30 formed in the abrasive layer 4 are large and the porosity is extremely large, clogging and overheating are less likely to occur than in the above-described embodiments.

FIG. 8 is a longitudinal sectional view showing another embodiment of the present invention. In this example, an annular cavity 16 is formed in the peripheral wall of the grindstone base 1, and a large number of gas passages 18 extending from the cavity 16 to the peripheral wall end face are formed at regular intervals in the circumferential direction. On the inner peripheral surface of the peripheral wall portion of the grindstone base 1, a large number of grinding fluid introduction holes 20 reaching the hollow portion 16 are formed at regular intervals in the circumferential direction.

It is desirable that these grinding fluid introduction holes 20 are formed so as to form an acute angle with respect to the gas flow direction in the hollow portion 16, whereby the grinding fluid ejected from the grinding fluid ejection hole H through the rotation axis S is formed. A part of the liquid is
The air merges with the air and flows into the gas passage 18 to be supplied to the porous abrasive layer 4. In this example, no grinding fluid dispersion layer was provided.

According to this embodiment, the same effects as those of the above embodiment can be obtained. In addition, the grinding fluid is sprayed on the shoulder portion of the grinding wheel base 1 during the rotation, so that the grinding fluid is directly supplied from outside, not from the rotation axis S. It can also be supplied to the porous abrasive layer 4.

It should be noted that the present invention is not limited only to the above embodiment, and for example, the shape of the grindstone base 1 and the shape of the blades 10 may be changed as necessary. Further, the porous abrasive layer 4 is not limited to the one having the above-mentioned structure, and a part of the abrasive particles is communicated with each other by performing normal electrodeposition using superabrasive particles plated in advance with metal. An abrasive layer having pores formed therein can also be used.

[0034]

As described above, according to the water-permeable cup-type grindstone according to the present invention, as the grindstone rotates, the suction blade structure provided on the outer peripheral surface of the grindstone base sucks air outside the grindstone, and the cavity portion is formed. To be introduced. The introduced air is then led out from the end face of the grinding wheel base through the gas passage.On the way, the grinding fluid supplied to the inside of the grinding wheel through the rotating shaft merges with the air, and along with the air, the grinding fluid flows from the end face of the grinding wheel base. It is supplied to the porous abrasive layer. Since the supplied grinding fluid and air travel while dispersing inside the porous abrasive layer and are released from the grinding surface, the porous abrasive layer is cooled by the grinding fluid and air in the process, preventing overheating. In addition, swarf adhering to the ground surface is washed away, so that clogging can be prevented. In addition, since a sufficient amount of grinding fluid is forcibly supplied to the grinding point, heavy grinding can be performed and the finished surface roughness of the work material can be improved.

On the other hand, when a grinding fluid dispersion layer is provided between the grinding wheel base and the porous abrasive layer, the grinding fluid flowing out of the end face of the grinding wheel base is parallelized by the porous dispersion layer. It is possible to effectively disperse in the direction and to distribute the grinding fluid over a wide area of the abrasive layer.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing one embodiment of a water-permeable cup-type grindstone according to the present invention.

FIG. 2 is a sectional view taken along line II-II of FIG.

FIG. 3 is a sectional view taken along the line III-III in FIG. 1;

FIG. 4 is an enlarged sectional view of an abrasive grain layer and a grinding fluid dispersion layer of the grinding wheel.

FIG. 5 is an enlarged view showing a resin porous body used for manufacturing the grinding wheel.

FIG. 6 is an enlarged sectional view showing a porous abrasive layer according to a second embodiment of the present invention.

FIG. 7 is an enlarged sectional view showing a porous abrasive grain layer according to a third embodiment of the present invention.

FIG. 8 is a longitudinal sectional view showing a water-permeable cup-type grindstone according to a fourth embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Whetstone base 2 Grinding fluid dispersion layer 4 Porous abrasive layer 6 Cavity 8 Opening 10 Blade (suction blade structure) 12 Gas introduction path (part of gas passage) 14 Gas outlet path (part of gas passage) 16 Cavity 18 Gas passage 20 Grinding fluid introduction hole 30 Continuous ventilation hole 32 Heat resistant coating 34 Metal filling layer 36 Super abrasive 38 Metal plating phase 40 Liquid supply hole 42 Resin porous body

Continuation of the front page (56) References Japanese Utility Model 62-156465 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) B24D 7/10 B24D 3/10 B24D 7/00

Claims (2)

(57) [Claims] 1. A grindstone base having a cup shape, and a porous abrasive layer having water permeability provided on an end face of a peripheral wall portion of the grindstone base, and a hollow portion is formed inside the grindstone base. At the same time, an opening communicating with the cavity is formed on the outer surface of the grindstone base, and a suction blade structure for sucking external air and introducing into the cavity as the grindstone base rotates is provided in the opening. And a gas passage which is opened to the end face of the grinding wheel base and is joined with the air on the way to join the grinding fluid to the inside of the grinding base, and is derived from the end face. Aqueous cup-type whetstone. 2. The water-permeable cup according to claim 1, wherein a grinding fluid dispersion layer having water permeability is provided between an end face of the grinding wheel base and the porous abrasive layer. Mold whetstone.