JP2011173180A - Truing device of circular arc concave grinding wheel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To select a rotating type rotary dresser as a dresser attached onto a machine frame for a trochoid gear shaping numerical control grinding device in order to improve a defect that fine dressing cannot be performed when a conventional swing type electrodeposition CBN forming grinding tool is used, and to perform dress shaping of a circular arc concave part of a circular arc concave grinding wheel for working by a rotary dresser grinding tool with superior dimensional accuracy. <P>SOLUTION: A rotary dresser grinding tool support arm 32 is arranged on the machine frame of a work stage 10 of the trochoid gear shaping NC grinding device 1, and the rotary dresser grinding tool 31 is liftably arranged. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

The present invention relates to a truing of a grinding wheel mounted on a grinding device that grinds a trochoid-shaped gear using an arc-shaped concave grinding wheel that is installed so that a workpiece supported by an indexing device (centering device) can move in the front-rear direction. Relates to the device. The grinding wheel used to form a trochoid-shaped gear dressed with this truing device is accurately trued to a size of 0.2 to 0.3 μm, so the service life of the grinding wheel is extended. (The time for replacing the grinding wheel of the trochoid-shaped gear can be lengthened).

As disclosed in the catalog “trochoid pump” (Non-Patent Document 1) on the Japan Oil Pump website, the tricolloid pump meshes with the outer gear (outer rotor) and the inner gear (inner rotor) that fits inside. An internal gear type pump that rotates in the form of a tooth, the tooth profile is formed by a tocoloid curve, the trochoid pump is a circular case and an outer disk, with teeth on the inside, and the hollow part is engaged with a pentagonal outer rotor and four It consists of a pin-shaped inner rotor with teeth, the drive shaft is attached to the center of the inner rotor, and the center of the inner rotor and the center of the outer rotor are eccentric. When the interrotor rotates, the outer rotor is driven in the same direction. For rotation, the inner rotor crest and the outer rotor trough mesh with each other at a short distance, but at the far end, there is one inner rotor crest, so the three spaces formed between the outer rotor are expanded. It contracts or shrinks, and it acts as a pump and forcibly sucks and discharges liquid.

Japanese Examined Patent Publication No. 3-3075 (Patent Document 1) discloses an uneven surface as a contact surface shape of a tooth profile in a trochoid motor or pump, and a tooth crossing the tooth trace direction of the tooth profile and the tooth trace direction of the grinding eye. And a contact surface having a tooth profile having a chemical conversion coating formed on the contact surface with a film thickness lower than the height of the unevenness.

Patent No. 4,345,468 (Patent Document 2) fixes a workpiece (grinding stone) to a holder that conveys the workpiece (grinding stone), and fixes the workpiece to the workpiece (forming wheel). A truing apparatus that performs truing using a position of the work piece with respect to a predetermined reference position and a phase shift from the reference phase by measuring the position of the fixed work piece. And a processing machine (forming grindstone) that performs truing by processing the workpiece based on the arrangement of the workpiece and the phase shift measured by the position measuring device. A truing device is proposed.

Using the truing device, the workpiece is fixed to a holder and conveyed, and the position measuring step and the processing step are performed by a position measuring device and a processing machine, respectively. And a positioning second positioning means corresponding to the first positioning means in the position measuring device and the processing machine, and when the holder is transported to the position measuring device, When the holder is placed at a predetermined position of the position measuring device by the first positioning means and the second positioning means provided in the position measuring device, and when the holder is transported to the processing machine, The retainer is disposed at a predetermined position of the position measuring device by the first positioning means and the second positioning means provided in the processing machine, and the position measured by the position measuring device is measured. The arrangement and the phase shift of the workpiece, proposes a truing method is also applicable to the cage after transported to the processing machine.

The above Patent No. 4,345,468 specification 2 discloses a combination of an outer rotor having 17 tooth teeth and an inner rotor having 16 tooth teeth in the drawing. A trochoid pump using a gear having 5 to 20 teeth on the outer rotor is commercially available except for one common point less than that of the teeth.

FIG. 2 shows a partial cross-sectional view of the drive mechanism of the arc concave grinding wheel 20 of the trochoidal gear, and FIG. 3 shows a state diagram in which the workpiece w is partially ground using the arc concave grinding wheel 20.

As a forming grindstone (molding dresser) of this arc concave grinding wheel, a swing-type electrodeposition CBN grindstone is currently used. When the arc concave portion of the arc concave grinding wheel 20 is contoured using the swing-type electrodeposition CBN grinding wheel, the arc concave hem R is slightly 0 with respect to the center R of the arc concave portion of the grinding wheel. It has been found that it is necessary to perform 300-500 μm correction dress molding because it is gentle around 5R. If this correction molding is not performed, the replacement time of the arc concave grinding wheel is advanced.

On the other hand, Japanese Patent Application Laid-Open No. 2010-23200 (Patent Document 3) discloses a grinding wheel that is formed in a disk shape and has a grinding portion for grinding a workpiece on an outer peripheral surface, and a grinding wheel that is formed in a disk shape and that A general-purpose tourer (fixed molding grindstone) formed with a truing concave groove to which the grinding portion is transferred, a detected portion provided in the general-purpose truer, and a grinding wheel and the other of the general-purpose tourer A distance sensor capable of detecting the position of the detected portion; and a corner of the recess or the circumferential groove is calculated based on a change in a detection distance by the distance sensor, and the total shape is calculated based on the position of the corner. This numerical control is performed using a numerically controlled grinding apparatus that includes an indexing unit that determines a position where the total truer and the grinding wheel face each other based on an output of the sensor that determines a position where the truer and the grinding wheel face each other. Grinding equipment There is disclosed a method of truing a wheel wheel provided on a grinding wheel shaft in contact with the truer while rotating.

The present inventors grinding an existing trochoidal gear forming grinding device using numerical control capable of XYZ positioning described in the above-mentioned Japanese Patent No. 4,345,468 and Japanese Patent Application Laid-Open No. 2010-23200. A numerically controlled grinding machine assuming that the machine is remodeled and the fixed molding wheel is replaced with a rotary dresser (cylindrical dresser or convex disk dresser with a circular concave groove of the circular concave grinding wheel shown in FIG. 2). As a result, it was found that it is necessary to devise the means for attaching the rotary dresser to the numerically controlled grinding apparatus and the attachment position on the machine frame.

Japanese oil pump website catalog “trochoid pump”, [online], [searched on February 16, 2010], <URL: http://www.mootaro.com/c/061/569/> Japanese Patent Publication No. 3-3075 Patent No. 4,345,468 JP 2010-23200 A

In order to improve the above-mentioned disadvantage that precision dressing using a conventional swing-type electrodeposition CBN forming grindstone is not possible, a rotary rotary dresser is selected as a dresser to be mounted on a machine frame of a numerically controlled grinding apparatus for forming a trochoidal gear. Determine the position of the dresser on the machine frame.

According to the first aspect of the present invention, there is provided a work stage in which a plurality of plate-like workpieces clamped by a clamp mechanism supported by a rotation shaft of a centering mechanism is fixed on a machine frame, and a tool table which can be moved back and forth on the machine frame. An arc concave portion of an arc concave grinding wheel is provided on a guide device that can be moved up and down in the vertical direction and is movable in the front and rear direction, and a grinding wheel rotating mechanism that rotationally drives the arc concave grinding wheel A numerically controlled grinding machine for machining trochoidal gears equipped with a tool stage equipped with a rotary to a dresser grindstone support arm provided on a vertical plane parallel to the axis of the axis of rotation of the centering mechanism on the machine frame of the work stage. The present invention provides a truing device for a grinding wheel characterized in that a dresser grinding wheel is provided so as to be movable up and down.

The invention of claim 2 is a disk-shaped grinding wheel in which the rotary dresser grindstone is obtained by transferring the arc-shaped concave groove of the arc-concave grinding wheel, and is made of a CBN vitrified grindstone or a diamond vitrified grindstone. A truing device for a grinding wheel of a trochoidal gear according to No. 1 is provided.

Using the XYZ axis coordinate reading mechanism of the numerically controlled grinding machine for trochoidal gear processing, the position coordinates of the arc concave grinding wheel and the position coordinates of the rotary dresser grinding wheel are detected, the distance between them is calculated, and the rotary dresser grinding wheel is Contouring and truing of the arc concave grinding wheel (formation dressing processing) by moving the rotating circular dressing grinding wheel to the rotary dresser grinding wheel in rotation contact with the rotating circular dressing grinding wheel. To start. Subsequently, the contouring truing is repeated to repeat the up-and-down movement of the rotary dresser grindstone and the forward and backward movement of the arc-shaped concave grinding grindstone, and the truing of the grindstone is finished.

Measure the surface dimensional accuracy of the grinding wheel after truing, and if it is 10 μm or more, resume contouring and truing and adjust the XYZ coordinate position with respect to the workpiece of the circular concave grinding wheel until the surface dimensional accuracy is 5 μm or less. Perform ring truing.

When the rotary dresser grindstone is a complete grindstone made of CBN vitrified grindstone or diamond vitrified grindstone, a dimensional accuracy of 2 to 3 μm can be achieved with one contouring truing, and the contouring truing is resumed. Opportunities are rare.

FIG. 1 is a front view in which a part of a numerically controlled grinding apparatus for forming a trochoidal gear is cut out. FIG. 2 is a front view in which a part of the drive mechanism of the arc concave grinding wheel is cut out. (Known) FIG. 3 is a side view showing a state where part of the teeth and valleys of the outer rotor is ground by an arc concave grinding wheel. (Known) FIG. 4 is a diagram showing the dimensions of the arc concave grinding wheel and the cylindrical rotary dresser. FIG. 5 is a perspective view of a disc-shaped gross grinding wheel.

Hereinafter, the present invention will be described in more detail with reference to FIGS. A numerically controlled grinding apparatus 1 for forming a trochoidal gear shown in FIG. 1 includes workpiece holding plates 13a and 13b and a slide rod supported on a rotary shaft 12 rotated on a machine frame B by a centering mechanism (actuator) 11. A work stage 10 that fixes a plurality of plate-like workpieces w sandwiched by a clamp mechanism 13 provided with 13c, a tool table 22 that can move back and forth (X-axis direction) on the machine frame B, and a left-right direction (Z-axis direction). ) Is moved on a tool table 23 that can be moved up and down by a servomotor 24 in a vertical direction (Y-axis direction), and an arc concave grinding wheel 25 mounted on a guide device 25 is used as a workpiece. Opposed tool stage 20
A rotary dresser grindstone 31 is vertically moved by a lift guide mechanism 33 on a dresser grindstone support arm 32 provided on a vertical plane parallel to the axis of the rotating shaft 12 of the centering mechanism above the machine frame B of the work stage 10. A truing stage 30 provided so as to freely move up and down (in the Y-axis direction) is provided.

The plurality of plate-like workpieces w sandwiched by the clamp mechanism 13 are rotated at an angle of 360 degrees by the number n of workpieces (trochoid gears) intended for the rotary shaft 12, and the arc-shaped concave grinding grinding wheel 25 is Position the workpiece (centering).

The arc concave grinding wheel 25 moves the tool table 23 in the left-right direction to determine the Z-axis coordinate facing the workpiece, and then moves the guide device 25 up and down to move the Y-axis coordinate relative to the arc concave grinding wheel 25. The position coordinates (Y, Z) facing the workpiece of the arc concave grinding wheel 25 are determined.

The rotational drive of the drive motor 27 on the tool stage is transmitted to the drive belt 28 to rotate the arc concave grinding wheel 25 around the axis, and then the tool table 22 is moved forward (X axis direction) by the servo motor 26. It is moved and brought into contact with the workpiece w, and the tooth crests and valleys of the gear 1 / n portion are ground. During grinding, the angle of the workpiece is determined, and the XYZ-axis coordinate movement of the arc-shaped concave grinding wheel 25 is performed to obtain a trochoidal gear having a desired dimensional accuracy.

As the rotary dresser grindstone 31, a cylindrical rotary dresser having a diameter smaller than the arc concave R of the arc concave grinding wheel 25 shown in FIG. 4 and a transfer of the arc concave of the arc concave grinding wheel 25 shown in FIG. A convex disk rotary dresser can be used, and the grindstone material is preferably a CBN vitrified grindstone or a diamond vitrified grindstone rather than an electrodeposited CBN grindstone. The cylindrical auto lead dresser grindstone 31 is moved downward so that the diameter surface thereof faces the arc concave surface of the arc concave grinding wheel 25.

In order to perform dressing of the arc concave surface of the arc concave grinding wheel 25 using the rotary dresser grindstone 31, the rotary dresser grindstone 31 is lifted and then stopped at the Y coordinate position of the diameter axis of the rotary dresser grindstone 31. . Then, the rotating arc concave grinding wheel 25 is moved forward and brought into contact with the rotating rotary dresser grinding wheel 31 to perform contouring dressing (truing). During dressing, the XYZ coordinate position of the arc-shaped concave grinding wheel 25 is moved, and if necessary, the clamp mechanism 13 is slightly tilted by the centering mechanism 11.

The truing device 1 of the arc concave grinding wheel 25 of the present invention can position the XYZ coordinates of the arc concave grinding wheel 25 and center the tilt of the rotary dresser grinding wheel 31, so that the circular concave shape has a high dimensional accuracy (accuracy of 2 μm or less). The arc-shaped concave surface of the grinding wheel 25 can be dressed.

DESCRIPTION OF SYMBOLS 1 Truing apparatus of an arc concave grinding wheel B Machine frame w Work 10 Work stage 11 Centering mechanism 12 Rotating shaft 13 Clamp mechanism 20 Tool stage 25 Arc concave grinding wheel 25 30 Dress stage 31 Rotary dresser grinding wheel 32 Dresser support arm

Claims (2)

It is possible to move up and down in a vertical direction on a work stage that fixes a plurality of plate-shaped workpieces clamped by a clamp mechanism supported by a rotating shaft of a centering mechanism on a machine frame and a tool table that can move back and forth on the machine frame. In addition, an arc concave portion of the arc concave grinding wheel is provided in the guide device that can move in the front-rear direction so as to face the workpiece, and a tool stage provided with a grinding wheel rotating mechanism that rotationally drives the arc concave grinding wheel is provided. In a numerically controlled grinding machine for machining trochoidal gears, a rotary dresser grindstone is provided on the machine frame of the work stage so that it can be raised and lowered on a dresser grindstone support arm provided on a vertical plane parallel to the axis of the rotation axis of the centering mechanism. A truing device for a grinding wheel characterized by that. 2. The trochoidal gear according to claim 1, wherein the rotary dresser grindstone is a disc-shaped gross grindstone in which an arc-concave groove of an arc-concave grinding wheel is transferred, and is made of a CBN vitrified grindstone or a diamond vitrified grindstone. Truing equipment for grinding wheels.

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