JPH1043829A - Grooving tool for fluid bearing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a grooving tool for a fluid bearing capable of fixing a tool member to a tool main body without generating deformation in a grooving part of the tool member. SOLUTION: In the grooving tool for the fluid bearing composed of plural spherical bodies 32 installed in the tool main body 22, plural housing recessed part 26 are provided in the end surface 24 of the tool main body 22 at an interval in the peripheral direction, a part of respective plural housing recessed part 26 is opened in the outer peripheral surface of the tool main body 22, plural spherical bodies 32 are respectively housed into plural housing recessed part 26 from the end surface 24, and a part of the spherical body is projected outside through the corresponding opening 28 of the tool main body 22.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a groove machining tool for machining a groove of a hydrodynamic bearing.

[0002]

2. Description of the Related Art A fluid bearing utilizing a fluid such as air or oil is known as a bearing for rotatably supporting a shaft member. The fluid bearing includes a shaft member and a sleeve member that supports the shaft member. For example, a herringbone-shaped groove is formed on an outer peripheral surface of the shaft member and / or an inner peripheral surface of the sleeve member.

As a groove machining tool for forming a groove of a fluid bearing on the inner peripheral surface of a sleeve member of a fluid bearing, there is, for example, one disclosed in Japanese Patent Application Laid-Open No. 4-348865. This known grooving tool includes a tool body and a steel ball for performing grooving, and a plurality of steel balls are provided at a distal end portion of the tool body at intervals in a circumferential direction. When performing grooving using this type of processing tool, the tool body is rotated relative to the sleeve member of the fluid bearing while moving in the axial direction. The sphere acts on the inner peripheral surface of the sleeve member, whereby a herringbone-shaped groove is formed on the inner peripheral surface of the sleeve member.

[0004]

Conventionally, the fixing of a steel ball to a tool body is performed, for example, as follows, and there are the following problems to be solved in connection with this fixing method. I do. Referring to FIGS. 6 and 7, a concave groove 4 is formed on the outer peripheral surface of the distal end portion of cylindrical tool body 2, and a plurality of steel balls 6 are fixed to concave groove 4 at intervals in the circumferential direction. Is done. The width W of the groove 4 is set slightly smaller than the outer diameter L of the steel ball 6, and the depth D of the groove 4 is set slightly smaller than the outer diameter L of the steel ball 6. The steel ball 6 is pressed into the concave groove 4 of the tool body 2 as shown in FIG. 7, for example. First, a plurality of steel balls 6 are arranged at substantially equal intervals in the concave groove 4,
Next, the tool main body 2 provided with the steel balls 6 is placed on, for example, a press table 8 of a press machine, and then the pressing tool 10 is moved up and down as shown by arrows to act on the steel balls 6. Then, the steel ball 6 is press-fitted and fixed in the groove 4 of the tool body 2.

However, in the conventional fixing method, as described above, when the steel ball 6 is press-fitted and fixed, the press table of the press machine and the pressurizing tool 10 exert a pressing action on a part of the steel ball 6. The above-mentioned part of the steel ball 6 may be deformed by the pressing action. The part receiving the pressurizing action of the steel ball 6 is a part projecting outwardly from the concave groove 4 of the tool body 2, and this part acts on the inner peripheral surface of the sleeve member during groove processing. Part. Therefore, when the above-mentioned part of the steel ball 6 is deformed, high-precision groove processing (rolling processing) cannot be performed, and the shape of the groove formed on the inner peripheral surface of the sleeve member changes. The shaft member cannot be stably rotatably supported as a bearing. Further, since the steel ball 6 is arranged in the concave groove 4 and press-fitted, the steel ball 6 is inserted into the tool body 2.
When it is difficult to arrange the shaft members at equal intervals in the circumferential direction, the intervals between the grooves formed in the sleeve member become uneven, and the shaft member as a fluid bearing is stably supported for rotation. Can not do it.

An object of the present invention is to provide a groove machining tool for a fluid bearing which can fix the tool member to a tool body without deforming a portion of the tool member to be grooved.

Another object of the present invention is to provide a groove machining tool for a fluid bearing in which the tool members can be arranged at substantially equal intervals in the circumferential direction of the tool body.

[0008]

SUMMARY OF THE INVENTION The present invention provides a tool body,
Consists of a plurality of tool members attached to the tool body,
A plurality of accommodating recesses are provided on the end surface of the tool main body at intervals in a circumferential direction, and a part of each of the plurality of accommodating concaves is opened on an outer peripheral surface of the tool main body. The member is housed in each of the plurality of housing recesses from the end face,
A groove machining tool for a hydrodynamic bearing, characterized in that a part thereof projects outward through a corresponding opening of the tool body. According to the present invention, each of the plurality of tool members is accommodated from the end surface thereof into a plurality of accommodation recesses provided at intervals in the circumferential direction on the end surface of the tool body. A substantially no force is applied to the part protruding from the opening of the tool body during fixing, and this part is prevented from being deformed. Also, since the tool member is housed in the housing recess of the tool body,
The positioning can also be performed accurately.

According to the present invention, each of the plurality of receiving recesses has a cylindrical shape, a part of a peripheral side surface thereof is elongated and opened on the outer peripheral surface of the tool body, and each of the plurality of tool members has a spherical shape. A plurality of spherical bodies each protruding outward from a corresponding opening.
According to the present invention, since each accommodating recess has a cylindrical shape and each tool member is formed of a spherical body, it is possible to provide a processing tool with a relatively simple configuration and high accuracy.

Further, in the present invention, the inner diameter of the plurality of recesses is set to be somewhat smaller than the outer diameter of the plurality of spherical bodies, and the plurality of spherical bodies are press-fitted into the plurality of recesses. It is characterized by. According to the present invention, the plurality of spherical bodies are press-fitted into the plurality of housing recesses, so that each spherical body can be accurately and reliably housed in the corresponding housing recess.

Further, the present invention is characterized in that a fixing member for fixing the tool member to the tool main body is provided on an end face of the tool main body. According to the present invention, a plurality of tool members can be reliably fixed to the tool body by the fixing member.

Further, according to the present invention, the fixing member has a fixing main body for fixing the tool member, the fixing main body is provided with a mounting projection or a mounting concave portion, and the mounting surface is provided on an end face of the tool main body. The mounting recess or the mounting projection is provided corresponding to the projection or the mounting recess, and the mounting projection or the mounting recess of the fixing member is fixed to the mounting recess or the mounting projection of the tool body. According to the present invention, the fixing member may be fixed by fixing the mounting projection or the mounting recess to the mounting recess or the mounting projection of the tool body, and both can be relatively easily and easily fixed.

Further, the present invention is characterized in that a male screw is formed in the mounting protrusion, a female screw is formed in the mounting recess, and the male screw of the mounting protrusion is screwed into the female screw of the mounting recess. According to the present invention, a male screw is formed on the mounting projection,
Since the female screw is formed in the mounting recess, the male screw and the female screw can be fixed by screwing together.

[0014]

FIG. 1 is a side view showing an essential part of an embodiment of a grooving tool according to the present invention, and FIG. 2 is an exploded sectional view showing the grooving tool of FIG. 1 in a partially exploded manner. FIG. 3 is a perspective view showing an end of the tool body of the grooving tool shown in FIG. 1, and FIG. 4 is a view showing the part viewed from the line IV-IV in FIG.

Referring to FIGS. 1 to 4, the illustrated grooving tool includes an elongated cylindrical tool body 22. As shown in FIG. 3, four receiving recesses 26 are formed at substantially equal intervals in the circumferential direction on the end face 24 of the tool main body 22. The accommodation recesses 26 are cylindrical, and each accommodation recess 2
6 is open to the outer peripheral surface of the tool body 22. As shown, the opening 28 of each accommodation recess 26 is
2 extends linearly in the axial direction from one end. At the center of the end face 24 of the tool body 22, a mounting recess is provided,
A female screw 30 is provided on the inner peripheral surface of the mounting recess.

Each receiving recess 26 of the tool body 22 has
And a spherical body 32 as a tool member as shown in FIG.
Is accommodated. The spherical body 32 can be made of, for example, a steel ball, and the spherical body 32 and the accommodation recess 26 are set in the following relationship. That is, the inner diameter L1 of the housing recess 26 is set slightly smaller than the outer diameter L2 of the spherical body 32. Therefore, each spherical body 32 is relatively weakly press-fitted into the corresponding accommodation recess 26, and a part of the spherical body 32 (the opening 2) is formed.
8) is an opening 2 formed in the tool body 22.
8 project radially outward. Also, the accommodation recess 2
6 is set to be slightly smaller than the outer diameter L2 of the spherical body 32. Therefore, when the spherical body 32 is accommodated in the accommodating recess 26, the other part (the portion on the end face 24 side of the tool main body 22) slightly protrudes from the end face 24 in the axial direction, and a fixing member 34 described later is fixed to the tool main body 22. Then, the fixing member 34 acts on the other part of the spherical body 32 (see FIG. 2). The tool member may be constituted by a member having a portion having an outer shape that is a part of a sphere, instead of the spherical body 32. In this case, the portion having the outer shape that is a part of the sphere is described later. Since this groove processing is performed, this portion protrudes radially outward through the opening 26 of the tool main body 22, and the receiving recess 26 is also formed in a shape corresponding to the shape of the tool member.

The fixing member 34 is a short cylindrical fixing main body 3.
6. The fixing main body 36 has an outer diameter substantially equal to the outer diameter of the tool main body 22. Therefore, when the fixing member 34 is fixed to the tool main body 22, the fixing member 34
The fixed main body portion 36 defines an outer peripheral surface extending substantially continuously from the tool main body 22. A mounting projection 38 projecting in the axial direction is integrally provided at the center of the fixed main body 36, and a male screw 40 is formed on the outer peripheral surface of the mounting projection 38.

The working tool described above can be assembled as follows. First, the housing recess 2 of the tool body 22
The spherical body 32 is inserted into 6. This insertion is performed by the tool body 22.
The spherical body 32 may be press-fitted from the side of the end face 24. When the spherical body 32 is press-fitted, the spherical body 32 is temporarily held in the corresponding accommodation recess 26 with a relatively weak force. Next, the fixing member 34 is fixed to the end of the tool main body 22. This fixing is performed by fixing the male screw 40 of the mounting projection 38 of the fixing member 34 to the tool body 22.
May be screwed onto the female screw 30 of the above. As a result, the fixing body portion 36 of the fixing member 34 acts on the spherical bodies 32 housed in the housing recesses 26, and each spherical body 32 moves between the bottom surface of the housing recess 26 of the tool body 22 and the inner surface of the fixing body portion 36. The sphere 32 is held between the tool body 22
Fixed to When fixing the spherical body 32, the fixing body portion 36 only acts on the spherical body 32 in the axial direction of the tool body 22, and thus the spherical body 32 of the tool body 22
No external force acts on the part that protrudes radially from the opening 28 of the spherical body 32, and the deformation of the part of the spherical body 32 is reliably prevented. In addition, the spherical body 32
Is inserted into the accommodating recess 26 formed in advance, the arrangement interval of the spherical bodies 32 corresponds to the interval between the accommodating recesses 26, and the spherical body 32
Can be easily arranged at equal intervals.

This working tool can be used, for example, to form a herringbone-shaped groove 44 on the inner peripheral surface of a sleeve member 42 shown in FIG. On the inner peripheral surface of the sleeve member 42, it is desirable that this portion projects somewhat radially inward with respect to the remaining portion, corresponding to the portion where the herringbone-shaped groove 44 is formed, With this configuration, the spherical body 32 of the working tool is formed into the sleeve member 42.
Only acts on the part protruding inward. When groove processing is performed on the sleeve member 42, for example, the sleeve member 42 is fixed to a chuck (not shown) of a processing machine. The processing tool is fixed to a tool holding means (not shown) of the processing machine, and is rotated in a circumferential direction perpendicular to the axial direction while the tool holding means moves in the axial direction with respect to the sleeve member 42, By moving the tool holding means, a groove 44 having the shape shown in FIG. 5 is formed.
When grooving is performed by the above-described processing tool, the spherical body 32
Since the part protruding from the tool body 22 is not substantially deformed, the machining of the groove 44 can be performed with high precision. The sleeve member 42 thus processed forms a fluid bearing with a shaft member (not shown) housed inside the sleeve member 42, and a magnetic fluid, an oil, and a fluid interposed between the sleeve member 42 and the shaft member. , Air and the like are used. Such a fluid bearing can be advantageously applied, for example, as a bearing that rotatably supports shaft members of various motors.

Although the embodiment of the working tool according to the present invention has been described above, the present invention is not limited to the above-described embodiment, and various modifications and alterations can be made without departing from the scope of the present invention. is there.

For example, in the illustrated embodiment, the tool body 22
The female screw 30 of the fixing member 34 and the male screw 40 of the fixing member 34 are screwed together to fix them. However, without providing the female screw 30 and the male female 40, the fixing member 34
The two can be fixed by simply press-fitting the mounting projection 38.

In the illustrated embodiment, the mounting recess is provided on the tool body 22 and the mounting projection 38 is provided on the fixing member 34. On the contrary, the mounting projection is provided on the tool main body 22 and fixed. A mounting recess may be formed in the member 34, and a male screw may be provided in the mounting protrusion of the tool body 22 and a female screw may be provided in the mounting recess of the fixing member 34.

Further, in the illustrated embodiment, four spherical bodies 32 are fixed to the tool body 22 at intervals in the circumferential direction. However, the present invention is not limited to this, and at least two or more spherical bodies 32 are fixed. Can be used as a machining tool for performing groove machining of a fluid bearing.

In the illustrated embodiment, the fixing member 34 is used to fix the spherical body 32 to the tool main body 22. However, the spherical body 32 is fixed to the receiving recess 26 of the tool main body 22 only by press-fitting. The fixing member 34 may be unnecessary. Also in this case, since the press-fitting pressing force on the spherical body 32 does not substantially act on a portion protruding from the opening 28, high-precision processing can be realized.

[0025]

According to the present invention, each of the tool members is housed in the housing recess formed in the end face of the tool body from the end face thereof. Is substantially free from force when fixed, and this partial deformation is prevented. Further, since each tool member is housed in the housing recess of the tool main body, the positioning can be performed accurately.

Further, according to the present invention, since each accommodating recess has a cylindrical shape and each tool member is formed of a spherical body, it is possible to provide a processing tool with a relatively simple configuration and high accuracy. .

Further, according to the present invention, since the plurality of spherical bodies are press-fitted into the plurality of housing recesses, each spherical body can be accurately and reliably housed in the corresponding housing recess.

Further, according to the present invention, since the fixing member is fixed to the end face of the tool main body, a plurality of tool members can be reliably fixed.

According to the present invention, the fixing member is fixed by
The mounting projection or the mounting recess may be fixed to the mounting recess or the mounting projection of the tool body, and both can be relatively easily and easily fixed.

Further, according to the present invention, since a male screw is formed in the mounting projection and a female screw is formed in the mounting recess, both can be fixed by screwing the male screw and the female screw.

[Brief description of the drawings]

FIG. 1 is a side view showing an embodiment of a groove machining tool for a fluid bearing according to the present invention.

FIG. 2 is an exploded cross-sectional view showing the groove machining tool of FIG. 1 in a partially exploded manner.

FIG. 3 is a perspective view showing an end of a tool main body of the grooving tool of FIG. 1;

FIG. 4 is a diagram showing a portion viewed from line IV-IV in FIG. 2;

5 is a cross-sectional perspective view showing a sleeve member that has been subjected to groove processing by using the groove processing tool of FIG. 1;

FIG. 6 is a side view showing an example of a conventional groove machining tool for a fluid bearing.

FIG. 7 is a view for explaining a manner of fixing a steel ball of the grooving tool of FIG. 6;

[Explanation of symbols]

 2, 22 Tool body 6 Steel ball 26 Housing recess 30 Female screw 32 Spherical body 34 Fixed member 36 Fixed main body 40 Female screw 42 Sleeve member

Claims (6)

[Claims] 1. A tool main body and a plurality of tool members mounted on the tool main body, a plurality of accommodating recesses are provided on an end face of the tool main body at intervals in a circumferential direction. Each of the storage recesses has a part thereof opened to the outer peripheral surface of the tool main body, and the plurality of tool members are respectively
A groove machining tool for a fluid bearing, wherein a part of the groove machining tool is accommodated in the plurality of accommodating recesses from the end face and partially protrudes outward through the corresponding opening of the tool body. 2. A method according to claim 1, wherein each of the plurality of receiving recesses has a cylindrical shape, and a part of a peripheral side surface thereof is elongated in an outer peripheral surface of the tool main body. 2. The groove machining tool for a fluid bearing according to claim 1, wherein the groove is formed of a spherical body, and a part of each of the plurality of spherical bodies protrudes outward from the corresponding opening. 3. An inner diameter of the plurality of housing recesses is set to be slightly smaller than an outer diameter of the plurality of spherical bodies, and the plurality of spherical bodies are pressed into the plurality of housing recesses. 3. The groove machining tool for a fluid bearing according to claim 2, wherein: 4. The fluid bearing according to claim 1, wherein a fixing member for fixing the tool member to the tool body is provided on the end face of the tool body. Grooving tools. 5. The fixing member has a fixing main body for fixing the tool member, the fixing main body is provided with a mounting projection or a mounting concave portion, and the end surface of the tool main body has A mounting recess or a mounting protrusion is provided corresponding to the mounting protrusion or the mounting recess, and the mounting protrusion or the mounting recess of the fixing member is fixed to the mounting recess or the mounting protrusion of the tool body. The groove machining tool for a hydrodynamic bearing according to claim 4, wherein the groove machining tool is used. 6. A male screw is formed in the mounting projection, a female screw is formed in the mounting recess, and the male screw of the mounting projection is screwed to the female screw of the mounting recess. A groove machining tool for a fluid bearing according to claim 5.