JP2006255871A - Honing grinding wheel and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a honing grinding wheel easy to manufacture at a low cost, free of breakage and peeling off of a grinding wheel, thereby having a structure capable of sufficiently exhibiting a performance of the grinding wheel. <P>SOLUTION: A honing grinding wheel is constituted so that a square columnar grinding wheels 5 are embedded in a grinding wheel base 6 in a manner of integrally joined with it, with its outer peripheral grinding wheel surface 5a exposed, and a constituent material of the grinding wheel base 6 is a sintered metal material equal to a connection material of abrasive grains in the grinding wheels 5 in strength and linear expansion coefficient. An integral joint of the grinding wheel base 6 and the grinding wheels 5 is performed in a sintering action during sintering the grinding wheel base 6. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a honing grindstone and a method for manufacturing the honing grindstone, and more particularly to a structure technology of a honing grindstone that can be exchangeably attached to a honing tool of a honing machine.

  In the honing process, for example, a fine grindstone is used for the purpose of further smoothing the inner surface of a workpiece (hereinafter referred to as a workpiece) finished by precision boring, grinding, etc., and improving the processing accuracy of the inner surface. It is a finishing method in which the inner surface of the workpiece is brought into surface contact and lightly ground, and is one of the precision finishing methods that can produce the best workpiece surface together with lapping and super finishing.

  There is a honing machine as a dedicated machine tool for performing this honing process, and its general basic structure is equipped with a honing tool that holds one to several honing stones. The workpiece surface is machined while applying a predetermined pressure to the honing grindstone and simultaneously pouring a large amount of machining fluid.

  By the way, the honing grindstone is configured to be exchangeably attached to the honing tool, and the general basic structure thereof is that the grindstone b is an adhesive on the upper surface of the grindstone base a, as shown in FIG. It is integrally joined and fixed by appropriate joining means c such as soldering or brazing. Then, as shown in FIGS. 7B and 7C, the honing grindstone G1 is detachably mounted on the grindstone groove e of the mandrel d of the honing tool in the honing machine.

  Although not specifically shown, the honing machine drives the mandrel d of the honing tool to be inserted into the hole to be machined and reciprocates while rotating, and protrudes to the outer periphery thereof. The hole to be machined is honed by the grindstone b.

  However, the honing grindstone having such a structure has the following problems.

(1) When an adhesive or soldering is used as the joining means c, since the adhesive force is weak, if the load applied to the grindstone b during honing is large, the grindstone b peels off from the grindstone base a. There is a problem that the service life is relatively short and the running cost is high. Moreover, in particular, in a structure in which several honing grindstones G1, G1,... Are mounted on the honing tool, when one honing grindstone G1 has a short life due to damage or the like, the remaining honing that can still be used. The grindstones G1, G1,... Must all be replaced at the same time, which is very uneconomical.

(2) When brazing is used as the joining means c, there is little problem of the above-mentioned whetstone b peeling off, but there is a problem that workability at the time of manufacture is very poor. That is, for example, when the grindstone head a is made of aluminum, it is difficult to bond the grindstone b to the grindstone bed a. On the other hand, when the grindstone a is made of steel (generally using hardened steel), the grindstone b has good adhesion to the grindstone a, but on the other hand, the hardness of the grindstone a is high due to the high heat during the heat bonding. For this reason, there is a problem that the shape accuracy of the honing grindstone G1 deteriorates due to thermal deformation of the grindstone head a, and in the worst case, it cannot be used.

(3) In any of the above structures, an external force in the rotational direction X acts on the honing grindstone G1 during the honing process. In FIG. 7B, a portion surrounded by a dashed line on the lower side is received and burdened here. However, as described above, since the mandrel d is generally made of hardened steel, when the grindstone b comes in contact with the portion of the grindstone groove e of the mandrel d, the mandrel d loses and wears quickly, and its life is shortened. There was a problem of becoming.

(4) In the structure in which the grindstone b is bonded and fixed to the upper surface of the grindstone head a, the width and length of the grindstone table a and the grindstone b are equal as shown in FIG. In finishing processing for trimming, not only the grindstone platform a but also the hard grindstone b are simultaneously shaved, which is very difficult to process, resulting in an increase in processing cost and an increase in product cost.

  In this regard, as shown in FIG. 8, a so-called mold-type honing grindstone G2 in which a grindstone g is embedded in the plastic grindstone base f with only the outer peripheral grindstone surface exposed is also developed. In this honing grindstone G2, the periphery of the grindstone g is surrounded and covered by the grindstone base f, and a strong holding force of the grindstone g by the grindstone base f is obtained (for example, Patent Document 1). reference).

  However, in such a mold type honing grindstone G2, when the grindstone g is worn during the honing process, the peripheral wall h of the grindstone base f is also shaved along with the wear. At this time, if the peripheral wall h on the front side with respect to the rotation direction (traveling direction) X of the mandrel d (the portion surrounded by the one-dot chain line on the lower side in FIG. 8B) is scraped, chips on the peripheral wall h Or, the chips are caught between the outer peripheral grindstone surface of the grindstone g and the bore diameter surface of the workpiece to be machined as they are.

  As a result, not only soft materials such as cast iron and raw materials, but also workpieces that are hard materials, due to chips or chips on the peripheral wall h, the bore diameter of the workpiece The surface may be scratched, and even if the workpiece is made of a hard material, there is a problem that a light (thin) scratch is attached, which causes a decrease in the finishing accuracy of the ground surface.

  In the mold type honing grindstone G2, the grindstone base f is made of plastic, so that the strength and hardness of the grindstone base f itself can be obtained even if it is a structure that provides a strong holding force of the grindstone g by the grindstone base f. Due to its limitations, further improvements were desired.

  That is, when the above-mentioned grindstone g uses WA (white fused alumina) abrasive grains or GC (green silicon carbide) abrasive grains, which have been the mainstream in the past, the abrasive grains often fall off. Since the processing load of g is low, the desired ability could be sufficiently exhibited even with a plastic mold type honing grindstone G2.

However, since the CBN (cubic boron nitride) abrasive grains were invented recently, these so-called superabrasive grains were used together with diamond abrasive grains because of their low dropout and accuracy stability. In the honing grindstone equipped with the grindstone g, the plastic mold-type grindstone head f has a material limit in the strength and hardness of the grindstone base itself, and the holding power of the grindstone g is insufficient in terms of strength and ability. There was a limit, and the original performance (processing accuracy and grinding wheel life) of super abrasive grains such as CBN abrasive grains and diamond abrasive grains could not be sufficiently obtained.
Japanese Utility Model Publication No. 1-84969

 The present invention has been made in view of such conventional problems, and the object thereof is easy and inexpensive to manufacture regardless of the type of grindstone, and there is no damage or peeling of the grindstone. An object of the present invention is to provide a honing grindstone having a structure capable of sufficiently exhibiting the performance of the grindstone.

 Another object of the present invention is to provide a method for producing a honing grindstone capable of stably supplying the honing grindstone.

  In order to achieve the above object, the honing grindstone of the present invention is a rod-shaped one that is replaceably attached to the honing tool, and a square column grindstone is mounted on the grindstone base that is mounted and supported on the tool body of the honing tool. It is integrally bonded in an embedded shape so as to expose the outer peripheral grindstone surface, and the constituent material of the grindstone table is a sintered metal material equivalent in strength and linear expansion coefficient to the abrasive grain bonding material in the grindstone. As a characteristic, the grindstone head and the grindstone can be integrally joined to each other by a sintering action when the grindstone head is fired.

  As a preferred embodiment, the grindstone is a superabrasive grindstone in which superabrasive grains such as fine diamond abrasive grains and CBN abrasive grains are bonded by a binding material such as metal bond, and the configuration of the grindstone base The material preferably includes a bonding material for abrasive grains in the above-described grindstone as a main material, and for example, a metal bond, a vitrified bond, or a resinoid bond is suitably used.

  Desirably, the constituent material of the grindstone table includes a metal material having a lower melting point than that of the bonding material of the abrasive grains in the grindstone.

  Furthermore, the outer peripheral grindstone surface of the grindstone is arranged in a state protruding from the outer peripheral surface of the grindstone base by a predetermined height according to the purpose, and the groove for the mounting band for attaching to the honing tool is a part of the grindstone base. Can be provided.

Moreover, the manufacturing method of the honing grindstone of the present invention is a method for producing the honing grindstone,
(1) a grindstone firing step of filling a grindstone material powder in a first mold and firing the grindstone;
(2) The grindstone fired in the grindstone firing step is positioned and fixed to the second mold, and the grinder is filled with the metal material powder of the grindstone and the grindstone is fired. Grinding wheel sintering and sintering process to form a honing wheel by sintering and bonding the wheel,
(3) It is characterized by comprising a finishing step of finishing a grinding wheel head portion of the honing wheel integrally formed by the grinding wheel baking and sintering step into a predetermined shape by cutting.

  As a preferred embodiment, in the grinding wheel bed firing / sintering step, a metal material powder of the grinding wheel bed is mainly composed of a bonding material of abrasive grains in the grinding wheel and has a lower melting point than that of the bonding material. A metal material powder comprising a material is used, and this metal material powder is filled in a second mold and heated at a heating temperature higher than the melting point of the low melting point metal and lower than the melting point of the binding material. The grindstone pedestal is fired and the grindstone pedestal and the grindstone are sintered and bonded simultaneously.

  According to the honing grindstone of the present invention, the grindstone base mounted and supported on the tool main body of the honing tool is integrally joined in a buried shape so that the outer peripheral grindstone surface is exposed, Since the constituent material is a sintered metal material that is equivalent in strength and linear expansion coefficient to the bonding material of the abrasive grains in the grindstone, various excellent effects as listed below can be exhibited.

(1) A large bonding force is obtained by bonding the grindstone and the grindstone head with a five-surface bonding, and in particular, the honing process is performed because the back surface of the grindstone is surrounded and reinforced by the grindstone table with respect to the rotation direction of the honing tool. Even with a large load applied to the grindstone at times, the grindstone does not peel off from the grindstone platform.

  As a result, not only honing wheels using conventional mainstream abrasive grains such as WA abrasive grains and GC abrasive grains, but also honing stones using super abrasive grains such as CBN abrasive grains and diamond abrasive grains, Regardless of the time, the performance of the grindstone can be fully demonstrated.

(2) Long running wheel life, which is a consumable item, can be kept low and running costs can be kept low. Especially, in the structure where several honing wheels are mounted on the honing tool and all these honing wheels are replaced at the same time. Is very economical.

(3) Since a large joining force can be obtained by joining the grindstone and the grindstone head with a five-sided joint, there is no need to use conventional brazing as a joining means, which is a drawback in brazing. It is possible to effectively prevent bad effects on the high-heated grinding wheel head due to heat adhesion.

(4) Since the back of the grindstone is surrounded by the grindstone table with respect to the rotation direction of the honing tool, even if an external force in the rotation direction acts on the honing grindstone during honing, contact with the grindstone groove of the mandrel Since it is a part of the wheel head of the honing grindstone, there is no problem that the mandrel loses and wears quickly due to this contact, and the life of the mandrel is not shortened.

(5) The constituent material of the grindstone table includes, as a main material, the same material as the binding material of the abrasive grains in the grindstone and the same strength and linear expansion coefficient (for example, the same material as the binding material that binds the abrasive grains of the grindstone) ), The strength of the grindstone is high and the linear expansion coefficient is equivalent, so that the distortion of the grindstone is small.

(6) When the grindstone is worn during the honing process, the peripheral wall portion of the grindstone table is also scraped along with this wear. In the present invention, the constituent material of the grindstone table is a bond that combines the abrasive grains of the grindstone. If the same material as the main material is included as the main material, the chips or chips of the grinding wheel table existing on the front side with respect to the rotation direction (traveling direction) of the honing tool are Even if it is caught in between, these chips or chips do not damage the inner surface of the hole to be machined, unlike the conventional mold type honing grindstone. For this reason, the problem that the finishing precision of a grinding surface is reduced is also effectively prevented, and high finishing precision of honing is ensured.

  Moreover, according to the manufacturing method of the honing grindstone of this invention, while being able to supply stably the honing grindstone which can exhibit the above outstanding effects, the grindstone is integrally joined to the grindstone base in an embedded form. The above-mentioned wheel head portion, which is easier to cut than a grindstone, is finished to a predetermined shape (including a groove for a mounting band for attaching to a honing tool) with a cutting tool such as an end mill, so that finishing is easy and quick. In addition, the accuracy is good and the manufacturing cost can be kept low.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  The honing grindstone according to the present invention is shown in FIGS. 1 and 2, and this honing grindstone 1 is specifically replaced with a mandrel 3 which is a tool body of the honing tool 2 as shown in FIG. 1 (b) and FIG. It is a rod-shaped metal mold-integrated grindstone that can be attached.

  The illustrated honing tool 2 includes a single honing grindstone 1, and is used by being exchangeably mounted on the front end or lower end of a rotating main shaft of a honing machine (not illustrated). The mandrel 3 is opened with a grindstone groove 3a for receiving and holding the honing grindstone 1, and the honing grindstone 1 is mounted in the grindstone groove 3a so as to protrude in the radial direction and to be removable and replaceable. Further, as shown in FIG. 3B, an extension rod 4 for expanding the honing grindstone 1 is provided in the mandrel 3 so as to be reciprocally movable in the axial direction. The honing grindstone 1 is expanded (cut) radially outward by the tip wedge 4a of the expansion rod 4 (not shown).

  As shown in FIGS. 1 and 2, the concrete structure of the honing grindstone 1 is formed by integrally bonding and fixing a grindstone 5 and a grindstone base 6.

  The grindstone 5 is a quadrangular prism shape, and minute abrasive grains are bonded by a binding material. As the abrasive grains, general abrasive grains such as WA and GC, and superabrasive grains such as diamond and CBN are intended. Depending on the purpose, a vitrified bond, a metal bond or the like is used as the bonding material. The grindstone 5 of the illustrated embodiment is a superabrasive grindstone in which fine diamond abrasive grains and superabrasive grains such as CBN abrasive grains are bonded together by a bonding material such as a metal bond.

  The grinding wheel base 6 is a part that is mounted and supported on the mandrel 3, and as a constituent material thereof, a sintered metal material that is equivalent in strength and linear expansion coefficient to the abrasive grain bonding material in the grinding wheel 5 is used. By using a sintered metal material, the strength of the grindstone base 6 can be increased as much as possible, and the distortion of the honing grindstone 1 itself can be reduced.

  More preferably, the constituent material of the grinding wheel base 6 includes a bonding material of abrasive grains in the grinding stone 5 as a main material, and the grinding stone 5 made of superabrasives such as diamond and CBN as shown in the illustrated embodiment. As a main material, a metal bond, a vitrified bond, or a resinoid bond is used depending on the purpose. In the illustrated embodiment, a metal bond made of a copper alloy powder is used.

  In addition, since the grindstone base 6 is made of a sintered metal material in this way, in the illustrated embodiment, the grindstone 5 and the grindstone base 6 are integrally bonded as described later when the grindstone base 6 is sintered. It is made to work.

  For this purpose, it is desirable that the constituent material of the grindstone table 6 includes a metal material having a lower melting point than the abrasive bonding material in the grindstone 5, and more preferably, the strength and hardness of the grindstone table 6 are lowered. In addition, a low melting point metal material having good fluidity even at a low heating temperature is used.

  The integral joining structure of the grindstone 5 to the grindstone base 6 is integrated with the grindstone base 6 so that the grindstone 5 is exposed so that the outer peripheral grindstone surface 5a is exposed, whereby the outer grindstone surface 5a of the grindstone 5 is integrated. The other five surfaces 5b to 5f are surrounded and covered by the grinding wheel base 6.

  In particular, when the honing grindstone 1 is mounted on the honing tool 2, the inner diameter side bottom surface 5 b and the back surface 5 c of the grindstone 5 are bonded and fixed to the grindstone base 6 with respect to the rotation direction X of the honing tool 2. As a result, the part 6a of the grindstone base 6 joined to the back surface 5c of the grindstone 5 functions as a reinforcing wall of the grindstone 5 against the external force in the rotational direction X received by the grindstone 5 during grinding.

  Further, as shown in FIGS. 1A, 1B, and 2B, the outer peripheral grinding wheel surface 5a of the grinding stone 5 is disposed in a state of protruding from the outer peripheral surface of the grinding wheel base 6 by a predetermined height. Yes.

  Further, attachment band grooves 7 and 7 for attaching to the mandrel 3 of the honing tool 2 are provided in the portion of the grinding wheel base 6.

  As shown in FIG. 3A, the honing grindstone 1 in which the grindstone 5 and the grindstone base 6 are integrally joined corresponds to the inner peripheral contour of the grindstone groove 3a of the mandrel 3, as shown in FIG. The bottom surface 1a of the expansion rod 4 provided in the mandrel 3 is an inclined surface corresponding to the inclined surface of the tip wedge 4a, and the expansion rod 4 moves forward in the axial direction. As a result of the cooperative action of the tip wedge 4 a of the rod 4 and the bottom surface 1 a of the honing grindstone 1, the honing grindstone 1 is expanded (cut) radially outward from the outer peripheral surface of the mandrel 3.

  Then, the manufacturing method of the honing grindstone 1 provided with the above structures is demonstrated, referring FIGS.

(I) Grinding wheel firing step: (See FIG. 4)
By the following steps 1) and 2), the grindstone material powder 5A is filled in the mold (first mold) 10 and the grindstone 5 is fired.

1) The grindstone material powder 5A is filled into the molding cavity of the first molding die 10 shown in FIGS. 4A and 4B, that is, the internal space surrounded by the carbon split dies 10a to 10f.

2) While heating the grinding stone material powder 5A from the outside of the molding die 10, the grinding stone material powder is moved by the relative movement of the upper and lower split molds 10a and 10d (in the illustrated case, the upper split mold 10a is lowered as a punch). 5A is pressurized, and the square columnar grindstone 5 is fired.

(II) Whetstone stand firing and sintering process: (See Fig. 5)
In the following steps 1) to 3), the grindstone base 6 is fired, and simultaneously, the grindstone base 6 and the grindstone 5 are sintered and bonded to form the honing grindstone 1.

1) The grindstone fired in the grindstone firing step is positioned and fixed in a molding cavity of a molding die (second molding die) 11 shown in FIGS. 5 (a) and 5 (b).

  Specifically, it is fitted and held in the grindstone positioning recess 12 of the mold 11 (provided at the center of the lower split mold 11d of the carbon split molds 11a to 11f).

2) Fill the molding cavity of the molding die 11 in which the grinding stone 5 is positioned and fixed, that is, the internal space surrounded by the split molds 11a to 11f, with the metal material powder 6A forming the grinding wheel base 6.

3) While heating the metal material powder 6A from the outside of the mold 11, the metal material powder is moved by the relative approaching movement of the upper and lower split molds 11a and 11d (in the case shown, the upper split mold 11a is lowered as a punch). 6A is pressurized and the grindstone base 6 is fired. At the same time, the grindstone base 6 and the grindstone 5 are sintered and bonded together to integrally form the honing grindstone 1 'shown in FIG.

  In addition, as described above, the metal material powder 6A of the grinding wheel base 6 includes a metal material having a lower melting point than that of the bonding material, as well as a bonding material of the abrasive grains in the grinding wheel 5 as a main material. The heating temperature is higher than the melting point of the low melting point metal contained in the metal material powder 6A described above, and the melting point of the binding material (that is, the heating temperature of the grinding stone material powder 5A in the grinding stone firing step (I)). Is set to a lower temperature.

  That is, in this step, when the grindstone base 6 is fired and at the same time, the grindstone base 6 and the grindstone 5 are sintered and bonded, and when the metal material powder 6A is composed only of a bonding material of abrasive grains in the grindstone 5, When firing is performed at the heating temperature and pressure applied to the grinding stone material powder 5A in the grinding wheel firing step (I) above, the fired grinding stone 5 is melted and deformed, and the abrasive grains are post-processed, that is, up to the region of the grinding wheel base 6. There is a risk that it will be difficult or impossible to cut in the final finishing process. Moreover, the characteristics of the grindstone 5 itself may change, and the grindstone performance may change.

  On the other hand, when the heating temperature and pressure are lowered, the grinding wheel material powder 5A does not reach the details in the molding cavity of the molding die 11 and a thin portion is generated. Or the wheel base 6 is so soft that it cannot withstand the processing pressure during use.

  Therefore, in the present embodiment, the low melting point metal powder that lowers only the melting point of the grinding wheel base 6 and improves the fluidity even at a low temperature without lowering the strength and hardness of the grinding wheel base 6 is the main material. In addition to the abrasive bonding material in the grindstone 5, the metal material powder 6A is sintered.

(III) Finishing process: (See Fig. 6)
A portion of the grinding wheel 6 of the honing grinding wheel 1 ′ (FIG. 5C) integrally formed by the grinding wheel firing and sintering process is finished into a predetermined shape by cutting.

  Specifically, first, the honing grindstone 1 ′, which is a work, is held and fixed to the work holding jig 13, and the upper portion of the grindstone base 6 including the mounting band grooves 7, 7 (that is, the honing) by the cutting tool 14. An outer peripheral portion of the grindstone 1 ′ other than the grindstone 5 is processed and formed into a predetermined shape (see FIGS. 6A and 6B). Subsequently, the work 1 ′ is turned upside down to the work holding jig 13. The lower portion of the grindstone table 6 including the bottom surface 1a is processed and formed into a predetermined shape by the cutting tool 14 to obtain a finished product honing grindstone 1 (see FIGS. 1 and 2).

  In this case, the grindstone base 6 is made of a sintered metal material having the same strength and linear expansion coefficient as the bonding material of the abrasive grains in the grindstone 5, but does not include abrasive grains like the grindstone 5, so that the finishing by cutting is performed. Processing is easy, and an end mill can be used as the cutting tool 14.

  Therefore, by using a complex machine tool such as a machining center, the complicated shape structure of the honing grindstone 1 can be easily cut in a short time by one machine tool (in the illustrated embodiment, the workpiece is machined). The workpiece 1 'can be detached from the holding jig 13 only twice), and the finishing accuracy is good and the manufacturing cost can be reduced.

  Thus, the honing grindstone 1 configured as described above is used by being exchangeably attached to the mandrel 3 of the honing tool 2. The honing tool 2 is attached to the tip of a rotating spindle of a honing machine (not shown), and the mandrel 3 is inserted into a work hole of a work (not shown) by driving the honing machine, and reciprocates while rotating. Then, honing of the hole to be machined is performed by the grindstone 1 protruding from the outer periphery.

  In this case, during the honing process, an external force in the rotational direction X acts on the honing wheel 1, and a large bonding holding force is obtained between the grindstone 5 and the grindstone base 6 in the honing grindstone 1. Even with such a large load, the grindstone 5 is not peeled off from the grindstone base 6.

  That is, the grindstone 5 is integrally joined to the grindstone base 6 so as to be embedded, and the grindstone base 6 is made of a sintered metal material that is equivalent in strength and linear expansion coefficient to the abrasive bonding material in the grindstone 5. Therefore, a large joining force is obtained by joining the grindstone 5 and the grindstone base 6 by the five-face joining, and the back surface 5c of the grindstone 5 is surrounded and reinforced by the grindstone base 6 with respect to the rotation direction X of the honing tool 2. It is structured. As a result, even if a large load is applied to the grindstone 5 during the honing process, the grindstone 5 is not peeled off from the grindstone base 6 and the life is long.

  Thereby, also in the honing grindstone 1 using super-abrasive grains such as CBN abrasive grains and diamond abrasive grains as in the present embodiment, the performance of the grindstone 5 can be sufficiently exhibited.

  Further, since a large bonding force can be obtained by bonding the grindstone 5 and the grindstone base 6 by the five-surface bonding, it is not necessary to use the conventional brazing as the joining means 8, which is a drawback of brazing. It is possible to effectively prevent the poor workability and adverse effects on the high-heated grinding wheel head due to heat bonding.

  Furthermore, since the back surface 5c of the grindstone 5 is surrounded and reinforced by the reinforcing wall 6a of the grindstone base 6 with respect to the rotational direction X of the honing tool 2, an external force in the rotational direction X acts on the honing grindstone 1 during the honing process. Even so, as shown in FIGS. 3A and 3B, the contact of the mandrel 3 with the grindstone groove 3 a is the reinforcing wall 6 a of the grindstone base 6 of the honing grindstone 1. There is no such problem as losing quickly and wearing out.

  Further, the constituent material of the grindstone base 6 is the same material as the bonding material of the abrasive grains in the grindstone 5 in terms of strength and linear expansion coefficient (in the illustrated embodiment, the same material as the bonding material that binds the superabrasive grains of the grindstone 5). Therefore, since the strength of the grindstone base 6 is high and the linear expansion coefficient is equivalent, the distortion of the grindstone 5 is small.

  Further, when the grindstone 5 is worn during the honing process, the peripheral wall portion including the reinforcing wall 6a of the grindstone base 6 is also scraped along with the wear. In this embodiment, the constituent material of the grindstone base 6 Since the main material is the same material as the bonding material for bonding the superabrasive grains of the grindstone 5, chips or chips of the grindstone table 6 existing on the front side with respect to the rotation direction (traveling direction) X of the honing tool 1 are present. Even if it is caught between the outer peripheral grinding wheel surface 5a of the grindstone 5 and the work hole inner diameter surface of the workpiece, these chips or chips will form the work hole inner diameter surface of the work like a conventional mold type honing grindstone. It won't hurt. For this reason, the problem that the finishing precision of a grinding surface is reduced is also effectively prevented, and high finishing precision of honing is ensured.

  The above-described embodiment is merely a preferred embodiment of the present invention, and the present invention is not limited thereto, and various design changes can be made within the scope.

  For example, the honing grindstone 1 of the illustrated embodiment is for a honing tool 2 whose application target includes a single honing grindstone, but the present invention includes a honing grindstone including a plurality of honing grindstones such as three or four. Of course, it can also be applied to tools.

  In addition, the present invention exhibits a remarkable effect in the honing grindstone 1 including the grindstone 5 using superabrasive grains such as CBN abrasive grains and diamond abrasive grains as in the illustrated embodiment. Of course, it is applicable also to the honing grindstone provided with the grindstone using WA abrasive grain or GC abrasive grain.

FIG. 1A is a perspective view, and FIG. 1B is an exploded perspective view seen from the front of a mandrel of a honing tool to which the honing grindstone is mounted. FIG. 2 (a) is a plan view, FIG. 2 (b) is a front view, and FIG. 2 (c) is a cross-sectional view along CC in FIG. 2 (b). FIG. 3A is a plan view of a honing grindstone mounting portion, and FIG. 3B is a cross-sectional view taken along line BB in FIG. 3A. . It is the schematic which shows the grindstone baking process of the honing grindstone, FIG.4 (a) is a front view, FIG.4 (b) is a top view. FIG. 5A is a front view, FIG. 5B is a plan view, and FIG. 5C is a front sectional view showing a formed honing grindstone. FIG. FIG. 6A is a schematic diagram showing a finishing process of the honing grindstone, FIG. 6A is a front view showing a state of cutting the upper portion of the grindstone table in a partial cross section, FIG. 6B is a plan view, and FIG. c) It is a front view which shows the state which cuts the lower part of a grindstone stand. FIG. 7 (a) is a front view of the honing grindstone, FIG. 7 (b) is a plan view corresponding to FIG. 3 (a) of the honing tool equipped with the honing grindstone, FIG. 7 (c). ) Is a cross-sectional view taken along line BB in FIG. It is a figure which shows the other conventional honing grindstone, FIG. 8 (a) is a front view, FIG.8 (b) is a top view.

Explanation of symbols

1 Honing wheel 2 Honing tool X Honing tool rotation direction 3 Mandrel (tool body)
3a Grinding wheel groove 5 of mandrel Grinding wheel 5a Outer surface grinding wheel surface 5A Grinding wheel material powder 6 Grinding wheel base 6A Metal material powder 7 Groove 10 for mounting band Mold (first molding die)
11 Mold (second mold)

Claims (12)

It is a rod that can be attached to the honing tool in an exchangeable manner,
The grindstone base mounted and supported on the tool body of the honing tool is integrally joined in a buried shape so that a square pillar-shaped grindstone exposes its outer peripheral grindstone surface,
The honing grindstone is characterized in that the constituent material of the grindstone is a sintered metal material having the same strength and linear expansion coefficient as the abrasive bonding material in the grindstone. The honing grindstone according to claim 1, wherein the grindstone head and the grindstone are integrally joined to each other by a sintering action during firing of the grindstone stand.   3. The honing according to claim 1, wherein the grindstone is a superabrasive grindstone in which superabrasive grains such as fine diamond abrasive grains and CBN abrasive grains are bonded together by a bonding material such as metal bond. Whetstone.   The honing grindstone according to any one of claims 1 to 3, wherein a constituent material of the grindstone base includes a bonding material of abrasive grains in the grindstone as a main material.   The honing grindstone according to claim 4, wherein a constituent material of the grindstone base includes a metal bond as a main material.   The honing grindstone according to claim 4, wherein a constituent material of the grindstone table includes vitrified bond as a main material.   The honing grindstone according to claim 4, wherein a constituent material of the grindstone base includes a resinoid bond as a main material.   The honing grindstone according to any one of claims 1 to 7, wherein a constituent material of the grindstone table includes a metal material having a lower melting point than a bonding material of abrasive grains in the grindstone. The honing grindstone according to any one of claims 1 to 8, wherein an outer peripheral grindstone surface of the grindstone is disposed in a state of protruding by a predetermined height from an outer peripheral surface of the grindstone base. The honing grindstone according to claim 9, further comprising a structure in which a groove for an attachment band for attaching to a honing tool is provided in a portion of the grindstone base. A method for producing a honing grindstone according to claim 1,
(1) a grindstone firing step of filling a grindstone material powder in a first mold and firing the grindstone;
(2) Positioning and fixing the grindstone fired in the grindstone firing step to a second mold, filling the metal mold powder of the grindstone in the mold and firing the grindstone stand, Grinding wheel sintering and sintering process to form a honing wheel by sintering and bonding the wheel,
(3) A honing grindstone manufacturing method comprising: a finishing step of finishing a grindstone head portion of a honing grindstone integrally formed by the grindstone baking and sintering step into a predetermined shape by cutting. In the grinding wheel calcination / sintering process, a metal material comprising, as a metal material powder of the grinding wheel base, a bonding material of abrasive grains in the grinding wheel as a main material and a metal material having a lower melting point than the bonding material Use material powder,
The grindstone is fired at the same time that the metal material powder is filled in a second mold and pressed at a heating temperature higher than the melting point of the low melting point metal and lower than the melting point of the binding material. The method of manufacturing a honing grindstone according to claim 11, wherein a stand and the grindstone are sintered and bonded.

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