JP2010284775A - Method for manufacturing regulating wheel for centerless grinding, regulating wheel, and method for manufacturing conical roller - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a regulating wheel for centerless grinding, in which processing equipment cost can be reduced, the various regulating wheels can be easily and efficiently processed in accordance with a leading of a screw, a width and an angle of a bottom surface of the screw or the like, and desired processing accuracy can be obtained, and to provide the regulating wheel, and a method for manufacturing a conical roller. <P>SOLUTION: In the regulating wheel 1 for centerless grinding, a spirally continuing leading screw groove 2 is provided around an outer periphery, the bottom surface 2a of each round of the screw groove 2 forms a conical part, a flange 3 is provided between the conical parts. In the method for manufacturing the regulating wheel 1, the regulating wheel 1 is driven to rotate around an axial center L1 of the regulating wheel, and a conical workpiece is brought into rolling contact with the bottom surface 2a of the screw groove 2. In finishing step to finish the bottom surface 2a of the screw groove 2, with a numerically-controlled lathe 4, the bottom surface 2a of the screw groove 2 is sequentially finished part by part in an axial direction by using a cutting tool 5 with a cutting edge having an axial width of the part of the bottom surface 2a of the screw groove 2. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a method for manufacturing an adjustment wheel for centerless grinding used for manufacturing a tapered roller of a tapered roller bearing used as a bearing for an automobile, an industrial machine, or the like, an adjustment wheel, and a method for manufacturing a tapered roller.

  A technique for grinding the outer diameter of a tapered roller by a through-feed method using a centerless grinding machine has been put into practical use (Patent Document 1). In general, when the outer diameter of the tapered roller Wr is machined by the through-feed method shown in FIG. 13 using a centerless grinding machine, it is necessary to apply a propulsive force and a rotational force to the tapered roller Wr simultaneously to the grindstone 20. For this reason, a metal screwed adjustment wheel 21 is used. Similarly, in order to process the crowned tapered roller Wr having a curvature on the outer diameter surface, as shown in FIG. Thus, grinding is performed so that the crowning is transferred to the outer diameter of the tapered roller while changing the posture of the tapered roller Wr.

Normally, the cross-sectional shape of the threaded portion of the adjusting wheel is composed of a screw bottom 24, a flange 25, and a thread 26 corresponding to the apex angle θw, length Lw, and average diameter Da of the tapered roller Wr, as shown in FIG. It is a screw having a composite shape having a certain lead 27. In particular, the crowning type adjustment wheel has a special shape in which the angle of the screw bottom is always constant with respect to the curvature 28 of the entire adjustment wheel.
Conventionally, as shown in FIG. 16, this adjusting wheel is processed by using a grinder and tilting the grindstone 29 in accordance with the lead of the adjusting wheel as indicated by an arrow 30 in FIG. The grindstone 29 is modified to match 31. After such correction of the grindstone 29, etc., the linear feed type adjusting wheel is uniaxially oriented, and the crowning feed type adjusting wheel is moved to the arrow 33 in FIG. A large amount of the grinding fluid 32 is applied to the adjustment wheel and the grindstone 29 while turning as shown.

Japanese Patent No. 3871015

Conventionally, screw grinders used for processing of adjustment vehicles are composed of various machine elements, are very expensive processing equipment, and are skilled in obtaining adjustment vehicle accuracy with stable quality. Operation skills were required. The processing of a screw-type adjusting wheel on a screw grinder requires various types of grinding wheels according to the screw lead, the width of the screw bottom, and the angle. It was.
Further, the threaded portion of the thread and groove cannot be machined by a screw grinder, and the adjustment wheel is mounted on another machine for machining the groove or groove as necessary.

  The object of the present invention is to reduce the processing equipment and to easily and efficiently process various adjustment wheels according to the screw lead, the screw bottom width, the angle, etc. It is to provide a manufacturing method of a centerless grinding adjusting wheel, a adjusting wheel, and a method of manufacturing a tapered roller capable of obtaining machining accuracy.

  The centerless grinding adjusting wheel manufacturing method according to the present invention is a centerless grinding adjusting wheel having a guide thread groove on the outer periphery that follows a spiral shape, and the bottom surface of each periphery of the thread groove is a conical portion. In which the screw groove is provided in a method for manufacturing an adjustment wheel that is rotationally driven around the adjustment axle shaft and causes the cone-shaped workpiece to roll-contact with the bottom surface of the screw groove. The finishing process of the bottom surface of the screw groove includes a finishing incompletely adjusted vehicle manufacturing process for manufacturing an incompletely adjusted vehicle that is an unfinished adjusting vehicle, and a finishing process for finishing the bottom surface of the threaded groove of the incompletely adjusted vehicle. The finishing process is characterized in that the bottom surface of the thread groove is sequentially finished by a part in the axial direction by a numerically controlled lathe using a cutting tool.

  According to this configuration, after manufacturing the incompletely adjusted vehicle in which the bottom processing of the thread groove is not processed, the bottom surface of the thread groove of the incompletely adjusted vehicle is finished. In the process of finishing the bottom surface of the thread groove, a numerically controlled lathe, that is, an NC (Numerical Controlled) lathe, is used, for example, with a cutting tool having a cutting edge having a partial axial width of the bottom surface of the thread groove. Then, the bottom surface of the thread groove is sequentially finished part by part in the axial direction.

As described above, since the finishing is sequentially performed partly in the axial direction, the groove bottom can be smoothly finished even with a cutting tool if the division width is set to be fine. Although it is necessary to change the tool position in sequence and repeat the machining many times, numerically controlled lathes are generally equipped with a threading cycle function as a standard function. By using it, it can be easily processed without creating a complicated program.
According to this method, it is not necessary to prepare various types of grindstones according to screw leads, screw bottom widths, angles, and the like, and it is not necessary to replace the grindstones. In this method, it is not necessary to use a tool along the shape of the thread groove, and a general-purpose cutting tool can be used. Therefore, the versatility of various types of adjustment vehicles can be improved, and it can be easily applied to a variety of adjustment vehicles. The rate can be increased. In this case, the processing cost of the adjustment vehicle can be reduced as compared with the conventional manufacturing method, and therefore the cost of the tapered roller can be reduced. Further, according to the manufacturing method of the present invention, it has been proved that processing accuracy equivalent to that of a conventional screw grinding wheel can be obtained.

  The finishing process is a process of repeating a machining cycle in which machining is performed by moving the cutting tool relative to the incompletely adjusted vehicle, and the machining cycle includes one end of the screw groove or the end of the thread groove from a standby position away from the incompletely adjusted vehicle. The cutting tool is moved to the cutting feed start position in the extended position and the other end of the screw groove of the unfinished adjustment car at a speed that matches the axial movement speed of the screw groove lead on the inner surface of the screw groove of the rotating incomplete adjustment car. Or a cutting feed process in which a part of the groove width of the bottom surface of the thread groove is cut by moving axially or axially and radially to the cutting feed end position as an extended position, and incomplete adjustment from the cutting feed end position This is a process of moving the cutting tool relative to the retracted position away from the vehicle and returning the cutting tool from the retracted position to the standby position. Cutting feed start position may be one that changes by a predetermined shift amount along a predetermined start position change path from the groove width direction of the end of the thread groove to the other end side.

  In the machining cycle, the cutting tool is advanced from the standby position to the cutting feed start position in the approaching process. In the cutting feed process, the cutting tool is moved at a speed matching the axial movement speed of the thread groove lead to the cutting feed end position by adding a radial movement component in the axial direction or without a radial movement component. To cut. In the returning process, the cutting tool is relatively moved from the cutting feed end position to the retracted position. Thereafter, the cutting tool is returned from the retracted position to the cutting feed start position. In this machining cycle, the cutting feed start position is changed by a predetermined shift amount along a predetermined start position changing path from one end to the other end side in the groove width direction of the thread groove between the respective machining cycles. By reducing this predetermined shift amount as much as possible, the roughness of the bottom surface of the thread groove is improved, and the planar accuracy close to the grinding surface is realized.

  Control for moving the cutting tool at a speed that matches the above-described thread groove lead can be carried out without creating a complicated program by using a thread cutting function that is generally provided in a numerically controlled lathe. That is, the numerical control device of a lathe is provided with a thread cutting function in which the moving speed of the tool is controlled by inputting the lead of the thread groove and the rotational speed of the spindle, and uses this function. Thus, the moving speed of the tool is controlled without giving a specific command.

  With respect to a cross section obtained by cutting the adjustment wheel along a virtual plane including the adjustment axle, an envelope connecting the same axial direction of each circumference of the thread groove along the adjustment axle is a straight line, and the cutting feed process Then, the cutting tool may be moved along the straight envelope. In this case, in the machining cycle, a path along which the cutting tool is moved in the axial direction from the cutting feed start position to the cutting feed end position is a path along the straight envelope.

  With respect to a cross section of the adjustment wheel cut along a virtual plane including the adjustment axle core, an envelope connecting the same axial position of each circumference of the thread groove along the adjustment axle axis direction is radially outside the adjustment axle axis direction. It may be a crowning curve protruding in the direction, and the cutting tool may be moved along an envelope of the crowning curve in the cutting feed process. In this case, a path along which the cutting tool is moved in the axial direction from the cutting feed start position to the cutting feed end position is a path along the envelope of the crowning curve.

  The cutting blade of the cutting tool may have a convex curve shape. By cutting a cutting tool with a convex curve at the tip of the cutting edge, partly in the axial direction along the bottom surface of the thread groove, a virtual flat surface that can be regarded as a flat surface in practice can be formed. it can. In this case, various shapes of the thread groove can be efficiently processed as compared with the processing method of transferring the tool shape. In other words, versatility with respect to the shape of the thread groove can be enhanced.

  The finishing process includes finishing of the end face of the buttock and the outer peripheral surface of the buttock in addition to the finishing of the bottom surface of the thread groove, and finishing of the bottom face, the end face of the buttock and the outer peripheral surface of the buttock. Processing may be performed separately and sequentially. For example, the bottom surface of the thread groove is sequentially finished along the axial direction with one cutting tool. Separately from the finishing of the bottom surface, the end surface of the flange is sequentially processed along the axial direction. Apart from the processing of the bottom face and the end face of the buttock, only the thread is processed sequentially along the axial direction. In this case, it is possible to reduce, for example, the number of times of switching of the cutting tool and shorten the cycle time of the machining cycle, rather than sequentially machining the bottom surface of each circumference, the end face of the flange, and the thread. . Therefore, the processing time can be shortened and the manufacturing cost can be reduced.

  The finishing process includes a step of machining a groove between the bottom surface of the thread groove and one end surface of the flange portion, and a groove between the bottom surface and the other end surface of the flange portion, and a state where the incompletely adjusted vehicle is supported by the main shaft In this finishing process, the bottom surface of the thread groove, the end surface of the flange portion, the outer peripheral surface of the flange portion, the Nusumi, and the groove between the bottom surface and the other end surface of the flange portion are processed in this finishing process. You can go. When machining these nuisances and grooves, machining can be performed without changing the gripping wheel while maintaining the state where the incompletely adjusted vehicle is supported by the main shaft, and so-called setup change becomes unnecessary. For example, it is only necessary to switch to a cutting tool dedicated to Nusumi processing or a cutting tool dedicated to grooving. Therefore, the operation rate of adjustment vehicle manufacturing can be further increased.

The incompletely adjusted vehicle may be one using a heat-treated material. Since turning can be performed after the heat treatment, the material can have a necessary and sufficient hardness, and minute strains and the like accompanying the heat treatment can be removed. Therefore, it is possible to obtain the necessary and sufficient hardness and to increase the dimensional accuracy of the adjusting wheel. In addition, the degree of freedom of design increases as the choices of applicable materials expand.
In the finishing process, the bottom surface of the thread groove may be finished without using a processing oil. In this case, the equipment for supplying the processing oil, the equipment for collecting the waste oil, and the like can be reduced, so that the equipment cost can be reduced.

The adjusting wheel of this invention is manufactured using the manufacturing method of any one of Claim 1 thru | or 9. In this case, processing equipment can be reduced, and various adjustment wheels can be realized in accordance with the lead of the screw, the width of the screw bottom, the angle, and the like.
The method for manufacturing the tapered roller according to the present invention is to manufacture the tapered roller while rotating the adjusting wheel of claim 10 around the center of the adjusting axle to cause the conical workpiece to roll in contact with the bottom surface of the thread groove. In this case, it is possible to reduce the cost per unit quantity of the tapered rollers, rather than using a conventional thread grinding wheel.

  The centerless grinding adjusting wheel manufacturing method according to the present invention is a centerless grinding adjusting wheel having a guide thread groove on the outer periphery that follows a spiral shape, and the bottom surface of each periphery of the thread groove is a conical portion. In which the screw groove is provided in a method for manufacturing an adjustment wheel that is rotationally driven around the adjustment axle shaft and causes the cone-shaped workpiece to roll-contact with the bottom surface of the screw groove. The finishing process of the bottom surface of the screw groove includes a finishing incompletely adjusted vehicle manufacturing process for manufacturing an incompletely adjusted vehicle that is an unfinished adjusting vehicle, and a finishing process for finishing the bottom surface of the threaded groove of the incompletely adjusted vehicle. In the finishing process, the bottom surface of the thread groove is sequentially finished part by part in the axial direction using a numerically controlled lathe and using a cutting tool, so that the processing equipment can be reduced and Lead, screw bottom width, angle, etc. Flip and the various regulating wheel can be processed easily and efficiently, it is possible to obtain a desired machining precision.

  Since the adjusting wheel of the present invention is manufactured using the manufacturing method according to any one of claims 1 to 9, the processing equipment can be reduced, and the lead of the screw, the width of the screw bottom, Various adjustment wheels according to the angle and the like can be processed easily and efficiently, and a desired processing accuracy can be obtained.

  In the tapered roller manufacturing method according to the present invention, the adjusting wheel according to claim 10 is driven to rotate around the adjusting axle and the tapered roller is manufactured while rolling the conical work piece on the bottom surface of the thread groove. Reduction can be achieved, and various adjustment wheels can be easily and efficiently processed according to the lead of the screw, the width and angle of the screw bottom, and desired processing accuracy can be obtained.

It is a top view which represents roughly the manufacturing method of the adjustment vehicle for centerless grinding which concerns on one Embodiment of this invention. It is a principal part enlarged view of the adjustment vehicle for centerless grinding. It is a block diagram which shows the conceptual structure of NC lathe. It is a front view of the NC lathe. (A) is a diagram showing one machining cycle for finishing the bottom surface of the thread groove part by part in the axial direction, and (B) is repeating the machining cycle to advance the finishing machining amount in the axial direction of the bottom surface of the thread groove. It is a figure which shows the step made to do. In the adjustment vehicle manufacturing method which concerns on embodiment of this invention, it is a principal part enlarged view showing the plane shaping | molding in the process cycle by the cutting tool whose front-end | tip is a convex curve shape. In the adjustment vehicle manufacturing method according to the embodiment of the present invention, it is a plan view schematically showing a manufacturing method of a crowning type adjustment vehicle. It is principal part sectional drawing which shows the example of a process of the thread groove of the adjustment wheel for centerless grinding which applied the processing cycle of the single blade cutting. It is a principal part top view of a crowning type adjustment wheel when turning with a fixed curvature. (A) is a figure for demonstrating the change of the threading start position which concerns on embodiment of this invention, (B) is a principal part enlarged view of FIG. 10 (A). It is a conceptual diagram which shows the concept of the single blade cutting using a thread cutting cycle. (A) is a figure explaining the thread cutting cycle of the linear feed of NC lathe, (B) is a figure explaining the circular thread cutting cycle of the crowning feed of the NC lathe. It is a top view which shows the example which processes a tapered roller outer diameter by a through feed system with a centerless grinding machine. It is a top view which shows the example which processes a crowning tapered roller with the same centerless grinding machine. It is principal part sectional drawing of the thread groove of the adjustment wheel for centerless grinding. It is a top view showing the processing method of the conventional linear feed type adjustment wheel. It is a top view showing the processing method of the conventional crowning feed type adjustment wheel.

  An embodiment of the present invention will be described with reference to FIGS. The centerless grinding wheel according to this embodiment is used, for example, when through-feed centerless grinding of the outer peripheral surface of a tapered roller of a tapered roller bearing. First, a schematic configuration of an adjustment wheel for centerless grinding (hereinafter simply referred to as an “adjustment vehicle”) will be described, and a schematic configuration of an NC lathe for manufacturing the adjustment vehicle, a manufacturing method of the adjustment vehicle, and the like will be sequentially described below.

A schematic configuration of the adjustment vehicle will be described.
As shown in FIGS. 1 and 2, the adjustment wheel 1 is attached to the outer periphery of the drum shaft 1a. The adjusting wheel 1 has a screw groove 2 for guiding following a spiral shape on the outer periphery, and a bottom surface 2a of each circumference of the screw groove 2 forms a conical portion, and a flange portion 3 is provided between the conical portions. . That is, the bottom surface 2a is defined by the spiral flange 3 and is formed in a conical shape following the spiral.
An annular nose 2b (see FIG. 8) is formed between the bottom surface 2a of the screw groove 2 and one end surface of the flange portion 3, and an annular groove 2c is formed between the bottom surface 2a and the other end surface of the flange portion 3. Is formed. The adjusting wheel 1 can be rotationally driven around the adjusting wheel shaft core L <b> 1 so that the conical workpiece can be brought into rolling contact with the bottom surface 2 a of the screw groove 2.

The NC lathe will be described.
As shown in FIGS. 3 and 4, a numerically controlled lathe, that is, an NC (Numerical Controlled) lathe 4 is used in the process of finishing the bottom surface 2 a of the screw groove 2. The NC lathe 4 includes a lathe body 4A that is a machine part and a numerical controller 18 that controls the lathe body 4A. The lathe body 4A is, for example, a turret lathe in which a feed base 14a that supports a turret-type tool post Ta is arranged on the side of the headstock 15. A main spindle 15a supported by the main spindle 15 is provided with a main spindle chuck 15aa for gripping an incomplete adjustment wheel W which is a workpiece for which the finishing of the adjustment wheel 1 is not processed. The spindle chuck 15aa and the tailstock shaft 7 support the incompletely adjusted wheel W at both axial ends. The spindle 15a is rotationally driven by a spindle motor (not shown). The feed base 14 is provided on the rails 16 and 16 of the bed Bd. The feed base 14a is movable in the left-right direction (X direction), and the feed base 14a is moved in the front-rear direction (Z direction) via a rail (not shown). ) And the turret type tool post Ta. The tool rest Ta is mounted on the feed base upper body 14b so as to be indexed and rotatable.

  The feed base 14a and the feed base upper body 14b are fed in the X and Z directions indicated by arrows in FIG. 3 by an X-axis servo motor 17 and a Z-axis servo motor (not shown) via feed screws, respectively. . As shown in FIG. 4, the turret tool post Ta has a polygonal drum-like front shape, and is indexed around the horizontal axis by an indexing motor (not shown) built in the feed base upper body 14b. Rotated. Tools 5A, 5B and the like are attached to each peripheral surface portion of the tool post Ta.

As shown in FIG. 3, the numerical control device 18 is of a computer type and includes an arithmetic control unit 19 that decodes and executes a machining program Pm described in NC code or the like. The arithmetic control unit 19 controls each part of the NC lathe 4, for example, controls the X-axis and Z-axis servomotors and the spindle motor. In addition to this, the arithmetic control unit 19 has a function of performing sequence control of each part of the lathe body 4A, for example, indexing rotation of the tool post Ta and opening / closing of the spindle chuck 15aa.
The numerical control device 18 is provided with a basic operation program BP as a part of the OS (operation program) of the arithmetic control unit 19 or separately from the OS, and the basic operation program BP according to an instruction of the machining program Pm. It is possible to control using As a part of the basic operation program BP, a threading cycle control program BPa for performing a threading cycle described later is provided.

A method for manufacturing the adjustment vehicle 1 will be described.
The adjustment vehicle manufacturing method according to this embodiment includes a finish incomplete adjustment vehicle manufacturing process and a finishing process. The finishing incompletely adjusted vehicle manufacturing process is a process of manufacturing an incompletely adjusted vehicle W in which only the finishing of the screw groove 2 of the adjusting wheel 1 is not processed. In this process, the screw groove 2 is provided and the bottom surface of the screw groove 2 is provided. The incompletely adjusted vehicle W in which the finishing process of 2a is not processed is manufactured. For example, in the final stage of the manufacturing process of the finished incompletely adjusted vehicle, the incompletely adjusted vehicle W is heat-treated, and the heat-treated incompletely adjusted vehicle W is subjected to turning by the NC lathe 4 described above. In the finishing incompletely adjusted vehicle manufacturing process, the incompletely adjusted vehicle W is manufactured by a machine different from the NC lathe 4. However, the incompletely adjusted vehicle W may be manufactured using the NC lathe 4.

  In the finishing process, the bottom surface 2a of the screw groove 2 of the incompletely adjusted vehicle W manufactured in the finishing incompletely adjusted vehicle manufacturing process is finished. In this finishing process, in particular, as shown in FIG. 1, the NC lathe 4 sequentially finishes the bottom surface 2a of the thread groove 2 part by part in the axial direction using a cutting tool 5 (5A). The cutting tool 5 (5A) has a cutting edge 5a having a partial axial width of the bottom surface 2a of the thread groove 2. The cutting edge 5a refers to the edge of the rake face.

  Specifically, as shown in FIG. 1, a general-purpose cutting tool 5A such as a turning tool can be used without using a working oil in a state where an incompletely adjusted vehicle is supported by a main shaft 15a and a tailstock shaft 7. Finish this unfinished car. In this case, a machining cycle (denoted by an arrow 9) in which machining is performed by moving the cutting tool 5A relative to the incompletely adjusted vehicle is repeated, and the bottom surface 2a of the thread groove 2 is sequentially finished in portions in the axial direction. Processing.

As shown in FIG. 5, the machining cycle 9 mainly includes an approaching process, a cutting feed process, and a returning process. In the approaching process, the cutting tool 5A is advanced from the standby position P0 away from the incomplete adjustment vehicle W to the cutting feed start position P1 at one end of the screw groove 2 or the extended position.
In the cutting feed process, the cutting tool 5A is moved to the other end or the extended position of the thread groove 2 of the incompletely adjusted vehicle W at a speed that matches the axial movement speed of the thread groove lead on the inner surface of the thread groove of the rotating incompletely adjusted vehicle W. The thread groove 2 is cut by moving in the axial direction up to the cutting feed end position P2.
In the returning process, the cutting tool 5A is relatively moved from the cutting feed end position P2 to the retracted position P3 away from the incompletely adjusted vehicle W, and the cutting tool 5A is returned from the retracted position P3 to the standby position P0.
As shown in FIGS. 5 and 6, the cutting feed start position P <b> 1 between the machining cycles 9 is changed along the predetermined start position changing path from one end to the other end side in the groove width direction of the screw groove 2. It is changed by a predetermined shift amount in the direction and the radial direction. The axial direction is indicated by an arrow Z in FIG. 6, and the radial direction is indicated by an arrow X in FIG.

For controlling the machining cycle 9, a threading cycle control program BPa in the basic operation program BP of the numerical controller 18 (FIG. 3) is used. This threading cycle control program BPa is a program for performing the threading cycle shown in FIG. 12, and is an NC code indicating a threading cycle in the machining program Pm, for example, “GOO” (○ is 1). Executed by a command line that starts with a letter. This command line is, for example, in the format of “GXX X-Z-F-”. "X-" is the first cut diameter, "Z-" is the Z coordinate of the end point of the screw, and "F-" is the lead of the screw. In the machining program Pm, a command line for instructing the cutting diameter for each round, a command line for the final cutting diameter, and a command line for moving the tool away from the workpiece are described in a line following the command line. Further, in the machining program Pm, a command line for bringing the tool closer to the workpiece and a command line for moving to the threading start point (that is, the cutting feed start position P1) are described before the command line of the thread cutting cycle.
The arithmetic control unit 19 of the numerical controller 18 (FIG. 3) executes a threading cycle according to the series of command lines. At this time, the thread cutting cycle control program BPa calculates the feed rate in the axial direction of the cutting tool 5 according to the lead and the spindle rotational speed from the screw lead and the spindle rotational speed commanded separately from the above. And execute. Therefore, it is not necessary for a person to calculate and program the axial feed rate of the cutting tool 5.

  By using the threading cycle control program BPa or the threading control function provided in such a numerical control device 19, finishing of the bottom surface 2a of the thread groove 2 of the incompletely adjusted vehicle W can be easily performed.

1, 2, and 5, with respect to a cross section cut along a virtual plane including the adjustment axle, the envelope that connects the same axial direction of each circumference of the thread groove along the adjustment axle is straight. It is. In this case, the cutting feed process of each machining cycle 9 performs thread groove cutting by so-called linear feed. This linear feed is to feed the tool in a direction parallel to the envelope.
FIG. 7 is a plan view schematically illustrating a method of manufacturing a crowning type adjustment vehicle in the adjustment vehicle manufacturing method according to the embodiment of the present invention.
When processing a crowning feed type adjusting wheel, as shown in FIG. 12 (B), the incompletely adjusted wheel is processed by a processing cycle 10 used for processing a drum-type screw. As shown in FIG. 9, the crowning feed type adjusting wheel has an envelope that connects the same axial direction of each circumference of the thread groove 2 along the adjusting axle axis direction with respect to a cross section cut along a virtual plane including the adjusting axle axis. Is a crowning curve protruding outward in the radial direction over the adjusting axle axis direction. The crowning feed is to move the cutting tool 5 along the envelope of the crowning curve in the cutting feed process.

  Here, FIG. 11 is a conceptual diagram showing the concept of single-blade cutting using a threading cycle. Usually, a thread-type screw with a large lead is cut by a certain amount δ in an oblique direction from the outer periphery of the workpiece 8 using the same cutting tool 5N as the screw shape, and finally the shape of this cutting tool 5N is transferred to the screw. Is molded. However, the centerless grinding adjustment wheel of the tapered roller to be machined this time has a flat bottom surface 2a of the thread groove 2 and an inclination with respect to the adjustment axle L1 and the crowning curvature, and the shape varies depending on the type. . Therefore, the processing method for transferring the tool shape as shown in FIG. 11 is not efficient.

On the other hand, in the manufacturing method according to the embodiment of the present invention, as shown in FIG. 6, the general-purpose cutting tool 5 in which the cutting edge 5a has a convex curve shape, that is, the edge of the rake face has a convex curve with a curvature R, is fixed. The imaginary plane 11 is formed by repeatedly performing single-edged cutting while shifting the amount δ1. The convex curve may be an arc shape, a parabola shape, or the like, and may be a convex curve having no inflection point. The “single-blade incision” is a method of giving incision and axial feed for advancing the tool along the inclined inner surface of the thread surface. On the other hand, a cutting method for cutting a tool in the diameter direction of the workpiece is called a right angle cutting or the like.
When manufacturing a crowning type adjustment wheel, the crowning type adjustment wheel having the same plane accuracy as the thread groove processed by the grinding wheel head turning type screw grinder shown in FIG. 16 is used together with the machining cycle 10 shown in FIG. Is processed.

この数式（１）より、分割幅（ν）つまり切削工具５を軸方向へずらす一定量δ１を可能な限り小さくすることで、ねじ溝２の底面２ａの粗さを改善し、研削面に近い平面精度を実現する。 When cutting is performed by the method shown in FIG. 6, the theoretical surface roughness Rmax is expressed by the equation (1) from the tool curvature (R) and the division width (ν).

From this mathematical formula (1), by reducing the division width (ν), that is, the fixed amount δ1 for shifting the cutting tool 5 in the axial direction as much as possible, the roughness of the bottom surface 2a of the screw groove 2 is improved and close to the grinding surface. Realize planar accuracy.

  FIG. 8 is a cross-sectional view of an essential part showing an example of machining of a thread groove of a centerless grinding adjusting wheel to which a machining cycle of single-blade cutting is applied. As shown in the figure, when the bottom surface 2a of the thread groove 2 is machined with a single-blade cut, the cutting feed start position at the right end of the adjustment wheel is shifted in the radial direction according to the inclination angle α of the bottom surface 2a of the thread groove 2. For each axial shift amount, it is linearly changed as indicated by the arrow A1. In this case, the number of repetitions is an “integer” remaining by dividing the screw bottom length along the inclination angle α of the bottom surface 2 a of the screw groove 2 by the axial shift amount.

  FIG. 9 is a plan view of an essential part of the crowning type adjustment wheel when turning with a constant curvature. This figure shows the shape change of the bottom surface 2a of the thread groove 2 when the linear machining cycle of FIG. 5 is replaced with a machining cycle for circular thread cutting. The bottom surface 2a of each circumference of the thread groove 2 is formed so as to translate with respect to the constant curvature Ra of the crowning. In this case, the posture of the tapered roller Wr does not change along the axial direction, and the crowning shape cannot be transferred to the tapered roller Wr.

  FIG. 10 is a diagram for explaining a change in the cutting feed start position according to the embodiment of the present invention. It is assumed that the thread groove 2 in the central portion of the adjustment wheel 1 repeats the machining cycle shown in FIG. 8 while shifting the position by the radial shift amount D1 along the bottom surface 2a. At this time, the tool trajectory 12 of the cutting tool 5 coincides with the radius specified in the machining cycle, that is, the machining program Pm, and increases by the radial shift amount D1 for each cycle along the inclination of the bottom surface 2a of the thread groove 2. . In this case, the cutting feed start position P1 at the right end of the adjustment wheel is on the intersection of the tool locus 12 and the division amount δ2.

That is, the cutting feed start position P1 is corrected for each cycle according to the division amount δ2 and the change amount of the tool locus 12. Thereby, a threaded adjustment wheel in which the bottom surface 2a of the thread groove 2 changes radially with respect to the curvature 22 as shown in FIG. 14 can be processed. However, at this time, strictly speaking, it is estimated that the screw shape is inconsistent between the central portion of the adjustment wheel 1 and the left and right end portions of the adjustment wheel 1, but in the centerless grinding shown in FIG. Since the processing accuracy of the central portion determines the roundness, roughness, etc. of the tapered roller Wr, a slight accuracy error at both ends of the adjustment wheel 1 is not fatal to the accuracy of the tapered roller Wr.
As a result of centerless grinding of the tapered roller Wr with the adjusting wheel 1 using the above method, it has been demonstrated that both the linear feed type and the crowning feed type can obtain the same processing accuracy as that of the screw grinding adjusting wheel. If this method is applied, it is also possible to process a specially shaped adjustment wheel that cannot be processed by a conventional method using a grindstone, or an adjustment wheel made of heat-treated material. Therefore, the degree of freedom in design is increased by expanding the choices of applicable materials and special shapes.

According to the manufacturing method of the centerless grinding adjusting wheel described above, the NC lathe 4 is used to cut the thread groove 2 by using the cutting tool 5 having a cutting edge having a partial axial width of the bottom surface 2a of the thread groove 2. The bottom surface 2a is sequentially finished part by part in the axial direction. If the division width for finishing the bottom surface 2a sequentially is set finely as appropriate, the bottom surface 2a can be smoothly finished by the cutting tool 5 as well. The NC lathe 4 is generally provided with a function of a threading cycle as a standard function, and uses the function of the threading cycle. Therefore, it can be easily processed without creating a complicated program.
According to this method, there is no need to prepare various types of grindstones according to the screw leads, the width in the axial direction of the bottom surface 2a, the angle, etc., and it is not necessary to replace the grindstones. In this method, it is not necessary to use a tool along the shape of the thread groove 2, and a general-purpose cutting tool 5 can be used. Therefore, the versatility of various types of adjustment vehicles can be improved, and it can be easily applied to a variety of adjustment vehicles. The rate can be increased. In this case, the processing cost of the adjustment vehicle can be reduced as compared with the conventional manufacturing method, and therefore the cost of the tapered roller can be reduced. Further, according to the manufacturing method of the present invention, it has been proved that processing accuracy equivalent to that of a conventional screw grinding wheel can be obtained.

In the finishing process, as shown in FIG. 6, the cutting feed start position between each processing cycle is shifted by a predetermined shift amount along a predetermined start position changing path from one end to the other end side in the groove width direction of the thread groove 2. Change it step by step. By making this predetermined shift amount as small as possible, the roughness of the bottom surface 2a of the screw groove 2 can be improved, and the planar accuracy close to the grinding surface can be realized. In other words, the more the number of repetitions of the machining cycle, the more the roughness of the bottom surface 2a of the thread groove 2 can be improved, and the plane accuracy close to the grinding surface can be realized.
As shown in FIG. 6, the virtual plane 11 can be formed by repeatedly cutting the cutting tool 5 having a convex curve shape with a curvature R at the cutting edge tip while shifting the cutting tool 5 by a certain amount along the bottom surface 2a. it can. In this case, various shapes of the thread groove 2 can be efficiently processed as compared with the processing method of transferring the tool shape of FIG. In other words, versatility with respect to the shape of the thread groove 2 can be enhanced.

  The groove bottom finishing process includes, in addition to the finishing of the bottom surface 2a of the thread groove 2, finishing processing of the end face of the flange portion 3 and the thread that forms the outer peripheral surface of the flange portion 3, and these bottom surface 2a and flange portion 3 It is also possible to finish the end face and the screw thread separately and sequentially. For example, a desired cutting tool 5 is specified by indexing and rotating the tool post Ta, and the cutting tool 5 sequentially finishes the bottom surface 2a of the thread groove 2 along the axial direction. When machining the end face of the collar part 3, the turret Ta is indexed and rotated, a cutting tool dedicated to this end face machining is designated, and the end face of the collar part 3 is sequentially machined along the axial direction. Apart from the processing of the bottom surface 2a and the flange end surface, only the thread is sequentially processed along the axial direction. In this case, it is possible to reduce the number of times of switching of the cutting tool and shorten the cycle time of the machining cycle, rather than sequentially machining the bottom surface 2a of each circumference, the end face of the flange 3 and the thread. Become. Therefore, the processing time can be shortened and the manufacturing cost can be reduced.

The finishing process may include a step of machining the screw 2b between the bottom surface 2a of the screw groove 2 and one end surface of the flange portion 3 and the groove 2c between the bottom surface 2a and the other end surface of the flange portion 3. In this case, the bottom surface 2a of the thread groove 2, the end surface of the flange 3 in the finishing process, the thread, the screw 2b, and the like in this finishing process without maintaining and holding the state where the incompletely adjusted vehicle W is supported by the main shaft 15a. The groove 2c may be processed. When machining the pussies 2b and the grooves 2c, so-called setup change is not required without maintaining and holding the incompletely adjusted vehicle W supported by the main shaft 15. For example, it is only necessary to switch to a cutting tool dedicated to Nusumi processing or a cutting tool dedicated to grooving. Therefore, the operation rate of adjustment vehicle manufacturing can be further increased.
When the incompletely adjusted vehicle W is made of a heat-treated material, for example, a heat-treated material that cannot be processed by a manufacturing method using a grindstone can be easily processed. Since turning can be performed after the heat treatment, the material can have a necessary and sufficient hardness, and minute strains and the like accompanying the heat treatment can be removed. Therefore, it is possible to obtain the necessary and sufficient hardness and to increase the dimensional accuracy of the adjusting wheel. In addition, the degree of freedom of design increases as the choices of applicable materials expand.

In the finishing process, since the bottom surface 2a of the thread groove 2 is finished without using any processing oil, the equipment for supplying the processing oil and the equipment for collecting the waste oil can be reduced, thereby reducing the equipment cost. be able to.
When the adjusting wheel 1 obtained by the manufacturing method according to this embodiment is rotationally driven around the adjusting axle axis L1 and the conical roller is manufactured while rolling the conical work to the bottom surface 2a of the screw groove 2, It is possible to reduce the cost per unit quantity of the tapered rollers, rather than using a thread grinding adjusting wheel.
As another embodiment of the present invention, machining may be performed by moving the cutting tool 5 relative to the incompletely adjusted vehicle W using a spindle moving type lathe.

DESCRIPTION OF SYMBOLS 1 ... Adjustment wheel 2 ... Screw groove 2a ... Bottom 2b ... Nusumi 2c ... Groove 3 ... Gutter 4 ... NC lathe 5 ... Cutting tool L1 ... Adjustment axle core P0 ... Standby position P1 ... Cutting feed start position P2 ... Cutting feed end position P3 ... Reverse position W ... Unfinished adjustment vehicle

Claims (11)

An adjustment wheel for centerless grinding, which has a spiral guide groove on the outer periphery, the bottom of each circumference of the screw groove forms a conical portion, and there is a flange between the conical portions. Then, in a method of manufacturing an adjustment wheel that is rotationally driven around the adjustment axle axis and causes the conical workpiece to roll-contact with the bottom surface of the thread groove,
A finish incompletely adjusted vehicle manufacturing process for manufacturing an incompletely adjusted vehicle, which is an adjusted vehicle having the threaded groove and finishing processing of the bottom surface of the threaded groove,
A finishing process for finishing the bottom surface of the screw groove of the incompletely adjusted vehicle,
In the finishing process, a centerless grinding adjusting wheel manufacturing method is characterized in that a bottom surface of the thread groove is sequentially finished part by part in the axial direction using a cutting tool with a numerically controlled lathe. In claim 1, the finishing process is a process of repeating a machining cycle in which machining is performed by moving a cutting tool relative to an incompletely adjusted vehicle,
The machining cycle is
An approach process in which the cutting tool is advanced from a standby position away from the unfinished adjustment vehicle to a cutting feed start position at one end or an extended position of the thread groove;
In the axial direction to the cutting feed end position that is the other end of the screw groove of the incompletely adjusted vehicle or the extension position of the cutting tool at a speed that matches the axial movement speed by the thread groove lead on the inner surface of the screw groove of the incompletely adjusted car that rotates. Or a cutting feed process in which a part of the groove width of the bottom surface of the screw groove is cut by moving in the axial direction and the radial direction;
It is a process of returning the cutting tool from the retracted position to the standby position by relatively moving the cutting tool to the retracted position away from the incompletely adjusted vehicle from the cutting feed end position,
The cutting feed start position between each processing cycle is changed by a predetermined shift amount along a predetermined start position change path from one end to the other end side in the groove width direction of the thread groove,
A method for manufacturing a centerless grinding wheel.   In Claim 2, about the cross section which cut | disconnected the said adjustment wheel by the virtual plane containing this adjustment axle core, the envelope which connects the axial direction same location of each periphery of the said thread groove along an adjustment axle core direction is a straight line. And a centerless grinding adjusting wheel manufacturing method in which the cutting tool is moved along the straight envelope in the cutting feed process.   The cross-section obtained by cutting the adjusting wheel along a virtual plane including the adjusting axle core according to claim 2, wherein an envelope that connects the same axial position of each circumference of the thread groove along the adjusting axle axis direction is an adjusting axle axis. A centering grinding adjusting wheel manufacturing method in which a crowning curve is projected radially outward over a direction, and the cutting tool is moved along an envelope of the crowning curve in the cutting feed process.   5. The method of manufacturing an adjustment wheel for centerless grinding according to claim 3, wherein a cutting edge of the cutting tool has a convex curve shape.   6. The finishing process according to claim 1, wherein the finishing process includes finishing of the end face of the flange and the outer peripheral surface of the flange in addition to the finishing of the bottom of the thread groove. A method of manufacturing an adjustment wheel for centerless grinding, in which finishing of the end face of the flange and the outer peripheral surface of the flange is sequentially performed separately from each other.   7. The finishing process according to claim 6, wherein the finishing process includes a step of machining a slot between the bottom surface of the screw groove and one end surface of the flange portion, and a groove between the bottom surface and the other end surface of the flange portion. The bottom surface of the thread groove, the end surface of the buttock, the outer peripheral surface of the buttock, the Nusumi, and the bottom surface and the other end surface of the buttock in this finishing process without maintaining and supporting the main shaft. Of manufacturing an adjustment wheel for centerless grinding, in which a groove of the center is processed.   8. The method of manufacturing an adjustment wheel for centerless grinding according to any one of claims 1 to 7, wherein the incompletely adjusted vehicle uses a heat-treated material.   9. The method of manufacturing an adjustment wheel for centerless grinding according to claim 1, wherein in the finishing process, the bottom surface of the thread groove is finished without using a processing oil.   An adjustment vehicle manufactured using the manufacturing method according to any one of claims 1 to 9.   11. A method of manufacturing a tapered roller, wherein the adjusting wheel according to claim 10 is rotationally driven around the axis of the adjusting axle so that the tapered roller is manufactured while rolling the conical work to the bottom surface of the thread groove.

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