JPH0569339A - Water permeable cup type grinding wheel - Google Patents

Abstract

PURPOSE:To prevent overheating and blinding by communicating an opening part with a cavity part inside of a cup type grinding wheel base body, providing suction vanes for introducing outside air in accordance with the rotation of the grinding wheel base body, in the opening part, moreover and disposing gas passages, leading out a grinding liquid together with the air, on an end surface of the grinding wheel base body. CONSTITUTION:A cavity part 6 is formed over all the periphery of a cup type grinding wheel base body 1, an opening part 8 communicated with the cavity part 6 is formed over all the periphery on an outer peripheral surface, and vanes 10 are provided at fixed intervals in the opening part 8. Moreover gas leading out passages 14 are formed at fixed intervals in a peripheral wall part of the grinding wheel base body 1. Outside air and/or a grinding liquid are supplied by the vanes 10 in the side of the grinding wheel base body 1 via the cavity part 6 and the gas introduction passages 12 in accordance with the rotation of the grinding wheel base body 1. At that time, a part of the grinding liquid, blown out from grinding liquid nozzles H through a rotation shaft S, together with the air flows into the gas extraction passages 14 to be supplied in a grinding liquid dispersion layer 2, and are discharged via respective communication pores 30 and moreover through liquid feed holes 40 of a porous abrasion grain layer 4.

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 work materials, and more particularly to improvement for preventing clogging of an abrasive grain layer and overheating.

[0002]

2. Description of the Related Art A general cup-shaped grindstone is a cup-shaped base metal (grinding stone base) with an abrasive grain layer of a certain thickness formed on the end surface of the peripheral wall. By fixing and rotating the rotating shaft of the board, the work material is ground by the end surface of the abrasive grain layer.

[0003]

However, with the above-mentioned cup type grindstone, it is inevitable that the abrasive grain layer becomes clogged during grinding, and the grinder is stopped every time a certain amount of work material is processed. Then, dressing must be performed to cure the clogging of the abrasive grain layer, which is a labor-intensive problem. Further, when heavy grinding is performed, the abrasive grain layer may be overheated, causing problems such as seizure on the work material.

[0004]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and it is a cup-shaped grindstone base and a porous abrasive grain having water permeability provided on an end surface of a peripheral wall portion of the grindstone base. A layer is formed inside the grindstone base, 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. Is provided with a suction vane structure for sucking in the air into the cavity, and further, the grinding fluid that is communicated with the cavity and opens at the end face of the grindstone base and is supplied to the inside of the grindstone base in the middle merges with the air. A gas passage leading from the end face is formed.

A grinding liquid dispersion layer having water permeability may be provided between the end surface of the grindstone base and the porous abrasive grain 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 the outside air and introduces it into the cavity. The introduced air is then led out from the end surface of the grindstone base through the gas passage, and in the middle, the grinding liquid supplied to the inside of the grindstone through the rotating shaft merges with the air, and together with this air, from the end surface of the grindstone base. It is supplied to the porous abrasive grain layer. The supplied grinding fluid and air are dispersed in the inside of the porous abrasive grain layer and are discharged and released from the grinding surface, so the porous abrasive grain layer is cooled by the grinding fluid and air in the process, preventing overheating. At the same time, the chips adhering to the ground surface are washed away and 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, grinding resistance can be reduced, and heavy grinding such as deep cutting can be achieved. In addition, good finished surface roughness can be obtained.

[0007]

EXAMPLES The water-permeable cup type grindstone according to the present invention will be described in detail below. 1 to 3 are views showing an embodiment of the present invention, in which reference numeral 1 denotes a cup-shaped grindstone base, 2
Is a grinding fluid dispersion layer fixed to the end face of the peripheral wall of the grindstone base 1,
Reference numeral 4 is a porous abrasive grain layer fixed to the end surface of the grinding fluid dispersion layer 2.

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

As shown in FIG. 3, all of these blades 10 are inclined at a constant angle with respect to the tangential direction of the outer peripheral surface of the peripheral wall portion, and when the grindstone base 1 rotates in the direction of the arrow shown in FIG. The grinding liquid supplied to the inside is sucked and forcedly introduced into the cavity 6.

In addition, inside the grindstone base 1, a gas introduction path (a part of the gas passage) 12 that extends from the hollow portion 6 to the inner surface of the shoulder portion 12 is formed.
However, a large number 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 the gas passage) 14 having one end open to the inner peripheral surface of the grindstone base 1 and the other end opening to the end face 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 on the inner peripheral surface of the peripheral wall portion of the gas outlet passage 14 is set to a position where the grinding liquid ejected from the grinding liquid ejection hole H of the rotary shaft S is sprayed.

As shown in FIG. 4, the grinding fluid dispersion layer 2 in this embodiment is a metal layer having a constant thickness in which the continuous ventilation holes 30 having a three-dimensional mesh structure are formed in a non-directional manner.
The communication holes 30 are open on both sides of the grinding liquid dispersion layer 2, and fluid can be passed through these communication holes 30 in a non-directional manner.

The inner wall surface of each communicating hole 30 is formed with a heat resistant coating 32 over the entire surface. This heat resistant coating 32
Is a metal or alloy having a relatively high melting point such as Ni, Co or Cu,
Alternatively, it is made of ceramics such as alumina and magnesia.

Around the heat resistant coating 32, the heat resistant coating 32 is provided.
Filling metal (or resin) 34 having a lower melting point is filled over the entire area to secure the strength. Examples of the material of the filling metal 34 include Al alloys, Sn alloys, Cu alloys and the like, but Al alloys are particularly preferable from the viewpoint of melting point and weight reduction. Further, as the filling resin 34, resins such as polyimide, epoxy and phenol can be used.

The heat resistant coating 32 is made of Ni or Ni.
When the filling metal 34 is made of a metal such as an alloy that is easily dissolved in acid and the filling metal 34 is made of a metal that is difficult to dissolve in an acid, such as an Al alloy, nitric acid or the like is passed through the communication holes 30 to dissolve only the heat-resistant coating 32. It may be removed and the inner diameter of the continuous ventilation hole 30 may be enlarged.

On the other hand, the porous abrasive grain layer 4 is formed by dispersing and fixing superabrasive grains 36 such as diamond or CBN in a metal plating phase 38 such as Ni, Co or Cu in a multilayer form. The average grain size of the superabrasive grains 36, the abrasive grain content rate, and the thickness of the porous abrasive grain layer 4 are appropriately determined according to the purpose of the grindstone.

Inside the porous abrasive grain layer 4, a vertical liquid supply hole 4 is provided.
A large number of 0s are formed at intervals, one end of each liquid supply hole 40 communicates with each of the continuous air holes 30, and the other end is open at the surface (ground surface) of the porous abrasive grain layer 4. ..

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

Next, the heat resistant coating 32 is formed over the entire surface of the fibers of the porous resin body 42 to have a substantially constant thickness. When the heat-resistant coating 32 is formed of a refractory metal such as Ni, Co, or Cu or its alloy, 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 the resin porous body 42. Dry to solidify. By repeating this operation and then sintering, the resin porous body 42 is thermally decomposed and removed, and at the same time, the communication holes 30 are formed.
Is formed.

A resin porous body 42 having a heat resistant coating 32 formed thereon.
Then, the molten metal 34 is filled. When the molten metal is sufficiently solidified, both sides of this plate material are ground to open the end portions of the continuous ventilation holes 30 to form the grinding liquid dispersion layer 2.

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

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

Next, while rotating the rotary shaft S and ejecting the grinding liquid from the grinding liquid ejection hole H through the liquid supply passage K, the abrasive grain layer 4 is applied to the work material and ground. Then, as the grindstone base 1 rotates, the blade 10 sucks the external air or / and the grinding liquid, and the air is supplied to the inner side of the grindstone base 1 through the cavity 6 and the gas introduction passage 12. If the porous abrasive grain layer 4 is in contact with the work material over the entire circumference thereof or if there is a small gap between them, the inside of the grindstone base 1 is pressurized and the air is guided to the gas outlet passage 14. Inflow. At this time, a part of the grinding fluid ejected from the grinding fluid ejection hole H through the rotary shaft S merges with the air, flows into the gas outlet passage 14, and is supplied to the grinding fluid dispersion layer 2. Therefore, 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 grain layer 4 and discharged from the grinding surface through the liquid supply hole 40.

In this process, the porous abrasive grain layer 4 is cooled with the grinding liquid and air to prevent overheating, and the chips adhering to the grinding surface are constantly washed away to prevent clogging. Therefore, the number of times grinding is stopped to eliminate clogging is reduced, seizure with the work material due to overheating of the abrasive layer 4 does not occur, and deterioration of grinding accuracy due to thermal expansion of the abrasive layer 4 is prevented. be able to. Moreover, 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. Therefore, the finished surface roughness of the work material can be improved.

Further, in this embodiment, the individual liquid supply holes 40
Since the inner diameter of the porous abrasive grain layer 4 is constant in the thickness direction of the porous abrasive grain layer 4, the diameter of the liquid supply hole 40 does not change even if the porous abrasive grain layer 4 wears during grinding. Therefore, there is no possibility that the flow rate of the liquid supply changes and the grinding conditions are affected.

Further, since the ventilation holes 30 having a three-dimensional mesh structure are formed all over the inside of the grinding liquid dispersion layer 2, the grinding liquid dispersion layer 2 has a cushioning property. Therefore, the porous abrasive grain layer 4 is softly contacted with the work material, the excessive cutting of the super abrasive grain 36 into the work material is prevented, and the finished surface roughness can be improved.

The porous abrasive grain layer 4 may have the structure shown in FIG. 6 or 7.

In the example of FIG. 6, the metal plating layer 38 is formed while the abrasive grains 36 are dispersed inside the resin porous body 42 shown in FIG.
Is deposited and filled in the inside of the resin porous body 42, the entire body is heated to remove the porous body 42, and the communication holes 30 are formed in the removal traces. In this example, the abrasive layer 4
Since the continuous ventilation hole 30 having a three-dimensional mesh structure is formed in the inside of the non-directionally over the entire area, the abrasive grain layer 4 is formed from the inner peripheral side.
The grinding liquid supplied to the inner surface of the abrasive grain layer 4 reaches the grinding surface while being dispersed inside the abrasive grain layer 4. Therefore, it is not necessary to provide the grinding liquid dispersion layer 2 as in the above embodiment, and it may be directly formed on the outer peripheral surface of the grindstone 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 porous resin body 42 by electroless plating, the metal coating layer was connected to the cathode to disperse the abrasive grains 36. The abrasive grains 36 are fixed to the surface of each metal coating layer by the metal plating phase 38 by applying electric current between the anodes facing each other in the plating solution and performing electrolytic plating. According to this example, since the continuous air holes 30 formed in the abrasive grain layer 4 are large and the porosity is extremely large, clogging and overheating are less likely to occur than in the above-described respective examples.

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

These grinding liquid introducing holes 20 are preferably formed so as to form an acute angle with respect to the gas flow direction in the hollow portion 16, and as a result, the grinding liquid ejecting holes H are ejected through the rotary shaft S. Part of the liquid is the cavity 16
Inside, it merges with air, flows into the gas passage 18, and is supplied to the porous abrasive grain layer 4. In this example, the grinding liquid dispersion layer is not provided.

In this example as well, the same effect as in the above-mentioned example can be obtained, and by spraying the grinding liquid onto the shoulder portion of the grindstone base 1 during rotation, the grinding liquid is directly supplied from the outside, not from the rotating shaft S. It can also be supplied to the porous abrasive grain layer 4.

The present invention is not limited to the above embodiment, and the shape of the grindstone base 1, the shape of the blades 10 and the like may be changed as necessary. Further, the porous abrasive grain layer 4 is not limited to the one having the above-described structure, and superabrasive grains which are metal-plated in advance are used to perform normal electrodeposition to partially communicate the abrasive grains with each other. It is also possible to use an abrasive grain layer having pores formed therein.

[0034]

As described above, according to the water-permeable cup type grindstone according to the present invention, as the grindstone rotates, the suction vane structure provided on the outer peripheral surface of the grindstone base sucks in air outside the grindstone to form a cavity. To introduce. The introduced air is then led out from the end face of the grindstone base through the gas passage, and in the middle of that, the grinding liquid supplied to the inside of the grindstone through the rotary shaft merges with the air, and together with this air, from the end face of the grindstone base. It is supplied to the porous abrasive grain layer. The supplied grinding fluid and air travel while dispersing inside the porous abrasive grain layer and are released from the grinding surface, so the porous abrasive grain layer is cooled by the grinding fluid and air in the process, and overheating is prevented. At the same time, the chips adhering to the ground surface are washed away and clogging can be prevented. Further, since a sufficient amount of the grinding liquid is forcibly supplied to the grinding point, it becomes possible to perform heavy grinding and improve the finished surface roughness of the work material.

On the other hand, when a grinding liquid dispersion layer is provided between the grindstone base and the porous abrasive grain layer, the porosity dispersion layer allows the grinding liquid flowing out from the end face of the grindstone base to be parallel to the grinding surface. It is possible to disperse the grinding fluid effectively in the direction, and to flow the grinding liquid in a wide range of the abrasive grain layer.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing an 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 line III-III in FIG.

FIG. 4 is an enlarged cross-sectional view of an abrasive grain layer and a grinding liquid dispersion layer of the whetstone.

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

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

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

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

[Explanation of symbols]

 1 Grindstone Base 2 Grinding Liquid Dispersion Layer 4 Porous Abrasive Grain Layer 6 Cavity 8 Opening 10 Blade (Suction Blade Structure) 12 Gas Inlet (Part of Gas Passage) 14 Gas Outlet (Part of Gas Passage) 16 Cavity 18 Gas passage 20 Grinding liquid introduction hole 30 Continuous ventilation hole 32 Heat resistant coating 34 Metal filling layer 36 Super abrasive grain 38 Metal plating phase 40 Liquid supply hole 42 Resin porous body

Claims (2)

[Claims] 1. A grindstone base of cup type, and a porous abrasive grain layer having water permeability provided on an end surface of a peripheral wall portion of the grindstone base, wherein a cavity is formed inside the grindstone base. At the same time, an opening communicating with this cavity is formed on the outer surface of the grindstone base, and a suction vane structure is provided in this opening for sucking in outside air and introducing it into the cavity as the grindstone base rotates. And a gas passage that opens to the end face of the grindstone base and joins the grinding liquid supplied to the inside of the grindstone base with the air to lead out from the end face. Aqueous cup type grindstone. 2. The water-permeable cup according to claim 1, wherein a grinding liquid dispersion layer having water permeability is provided between the end surface of the grindstone base and the porous abrasive grain layer. Type grindstone.