JPH09264738A - Method for measurement of gear and machine therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To measure the tooth profile and the tooth trace of a gear easily and with a comparatively simple configuration. SOLUTION: A measurement is performed by using a gear measuring machine which is provided with an X-Z-axis movement mechanism 2 which is arranged and installed on a surface plate 1 and in which a movable head 5 movable to the X-axis direction and the Z-axis direction is installed, with a displacement sensor 6 which is fixed to the movable head 5 and which outputs a displacement signal according to the movement of a contact maker and with an A-axis rotation mechanism 11 which is arranged and installed on the surface plate, by which the center of a rotary column is situated on the X-axis passing the contact maker 6a at the displacement sensor 6 and by which a gear to be measured is held horizontally on the central axis of the rotary column. In a state that the tip of the contact maker at the displacement sensor is placed in the measurement starting origin inside the tooth space of the gear to be measured so as to come into contact with a tooth flank, the displacement sensor 6 is moved along the Z-axis by the X-Z-axis movement mechanism 2. Alternatively, the displacement sensor 6 is moved along the Z-axis by the X-Z-axis movement mechanism 2, the gear to be measured is turned on the A-axis by the A-axis rotation mechanism 11, a displacement signal which is outputted from the displacement sensor 6 is fetched, and the tooth trace is measured on the basis of displacement data.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gear measuring method and a measuring machine therefor, which are used for inspecting gears and the like, and can easily measure the error of the tooth profile and the tooth trace of the gear with a relatively simple device.

[0002]

2. Description of the Related Art Conventionally, a tooth profile and a tooth trace of a gear are generally measured by using a three-dimensional coordinate measuring machine. The three-dimensional coordinate measuring machine is equipped with a linear gauge on each axis of the three-dimensional movement mechanism, a touch sensor is attached to the moving head, and a touch sensor is attached to each measurement point of the gear to be measured placed on the surface table. By making contact, the coordinate data of each point on the outer surface of the gear is collected, and the tooth profile and the tooth trace are measured by connecting the coordinate data plotted by the touch sensor.

[0003]

However, in such a conventional three-dimensional coordinate measuring machine, since a linear gauge is provided on each axis, the structure of the apparatus becomes complicated and the manufacturing cost becomes high. There was a problem. Further, when measuring a gear with a three-dimensional coordinate measuring machine, the touch sensor is manually moved along the outer surface of the gear while the coordinate data of each point is collected, so that considerable time and skill are required for measurement. However, there is a problem that the tooth profile and the tooth trace of the gear cannot be measured easily and efficiently.

The present invention has been made in view of the above points, and an object thereof is to provide a gear measuring method and a measuring machine therefor which can easily measure the tooth profile and the tooth trace of a gear with a relatively simple structure. To do.

[0005]

The gear measuring method of the present invention for solving the above-mentioned problems is an XZ-axis moving mechanism provided with a moving head which is arranged on a surface plate and is movable in the X-axis and Z-axis directions. The displacement column is fixed to the moving head and outputs a displacement signal according to the movement of the contact, and the center of the rotation column is located on the X axis, which is arranged on the surface plate and through which the contact of the displacement sensor passes, and the rotation column is positioned. A method for measuring a gear by using a gear measuring machine equipped with an A-axis rotating mechanism that horizontally supports a gear to be measured on a central axis of, and a tip of a contact of a displacement sensor is The displacement sensor is moved along the Z-axis by the XZ-axis moving mechanism or the displacement sensor is moved along the Z-axis by the XZ-axis moving mechanism in a state where it is placed at the measurement starting origin in the tooth groove and is in contact with the tooth surface. The measured gear is moved on the A-axis by the A-axis rotation mechanism. By rolling takes a displacement signal output from the displacement sensor, and performs tooth trace measurement based on the displacement data.

Further, the gear measuring method according to claim 2 is
A gear measuring method using the same gear measuring machine,
The displacement sensor is moved along the X axis by the XZ axis moving mechanism in a state where the tip of the contact of the displacement sensor is placed at the measurement start origin in the tooth groove of the gear to be measured and is in contact with the tooth surface. It is characterized in that the gear to be measured is rotated on the A axis by the shaft rotation mechanism, the displacement signal output from the displacement sensor is taken in, and the tooth profile is measured based on the displacement data.

[0007]

[Operation / Effect] When performing the tooth trace measurement, first, the tip of the contact of the displacement sensor is placed at the measurement start origin in the tooth groove of the gear to be measured, and the measurement is started in the state of being in contact with the tooth surface. When the gear to be measured is a spur gear, the displacement sensor is driven along the Z-axis by the XZ-axis moving mechanism to automatically move while contacting in the tooth flank direction of the tooth surface, and output from the displacement sensor. The displacement signal is read, and the tooth trace is measured based on the displacement data.

When the gear to be measured is a helical gear, the displacement sensor is driven along the Z axis by the XZ axis moving mechanism, and at the same time, the gear to be measured is rotationally driven on the A axis by the A axis rotating mechanism. Simultaneous two-axis control is performed, and the displacement sensor automatically moves while contacting the tooth trace direction of the gear to be measured. At this time, the tooth trace measurement is performed based on the displacement data output from the displacement sensor.

On the other hand, in the case of measuring the tooth profile, the tip of the contact of the displacement sensor is placed at the measurement starting origin in the tooth groove of the gear to be measured, and the measurement is started in the state of being in contact with the tooth surface. The displacement sensor is driven along the X-axis by the XZ-axis moving mechanism, and the gear to be measured is rotationally driven on the A-axis by the A-axis rotating mechanism to perform simultaneous two-axis control. While being in contact with the tooth surface, it automatically moves in the direction of the tooth profile, and at this time, the tooth profile can be measured based on the displacement data output from the displacement sensor.

In this way, after the position of the contact of the displacement sensor is set at the measurement starting origin, the displacement sensor is automatically moved along the Z axis or automatically moved along the Z axis. At the same time, the gear to be measured is rotated on the A axis, or the displacement sensor is automatically moved along the X axis.
By rotating the gear to be measured on the A axis, the tooth trace or tooth profile can be easily measured.

Further, in the gear measuring machine for carrying out such a measuring method, it is not necessary to provide a linear scale on each axis as in the conventional case, and a three-axis system of X axis, Z axis and A axis can be adopted. Therefore, as compared with the conventional 4-axis method, the structure of the measuring machine is simplified and the manufacturing cost can be reduced.

[0012]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a front view of the gear measuring machine, FIG. 2 shows its plan view, and FIG. 3 shows its right side view. Reference numeral 1 is a surface plate, and an XZ axis moving mechanism 2 is provided on the surface plate 1. The XZ-axis moving mechanism 2 has a horizontal moving part 3 and a vertical moving part 4. The horizontal moving part 3 is provided with a ball screw 3a and a guide shaft 3b supported in the horizontal direction, and the X-axis moving mechanism 3 is provided there.
The shaft moving portion 3c is screwed and engaged.

An X-axis servomotor 7 is attached to the end of the horizontal moving section 3, and the ball screw 3a is attached to the X-axis servomotor 7.
Is driven to rotate. Rotation of the ball screw 3a causes X
The axis moving unit 3c can move in the left-right direction (X-axis direction) in FIG. An X-axis encoder 8 that outputs a frequency signal according to the number of rotations is attached to the X-axis servomotor 7.

A vertical moving unit 4 is mounted on the X-axis moving unit 3c, and a ball screw 4a is vertically supported in the vertical moving unit 4. Then, the Z-axis moving portion 4b is screwed onto the ball screw 4a and arranged so as to be movable in the vertical direction (Z-axis direction), and protrudes outside the Z-axis moving portion 4b to move the moving head 5a.
The moving head 5 is moved in the X-axis and Z-axis directions by driving the XZ-axis moving mechanism 2.

A contact type displacement sensor 6 is attached to the moving head 5 via an attachment arm 5a. A so-called electric micrometer is used for the displacement sensor 6, generates a voltage signal according to the displacement of the displacement of the shaft-shaped contactor 6a, and outputs a displacement detection signal with a resolution of 0.1 μm, for example.

A Z-axis servomotor 9 is attached to the upper end of the vertical moving section 4, and the ball screw 4a is attached to the Z-axis servomotor 9
Is driven to rotate, and the Z-axis moving unit 4b moves up and down. Z
A Z-axis encoder 10 that outputs a frequency signal corresponding to the number of rotations is attached to the axis servo motor 9.

A gear G to be measured is horizontally supported on a surface plate 1 adjacent to the XZ axis moving mechanism 2 and is rotated at a low speed A.
A shaft rotation mechanism 11 is provided. In the A-axis rotating mechanism 11, the rotating column 12 is erected on the surface plate 1, the lower mandrel 13 is mounted on the rotating column 12, and the lower mandrel 1 is installed.
A support column 15 having an upper mandrel 14 provided so as to be vertically movable is provided immediately above the column 3 at an adjacent position.

An A-axis servomotor 16 for driving the rotary column 12 to rotate is mounted in the surface plate 1, and an A-axis encoder 17 for outputting a frequency signal corresponding to the number of rotations is attached to the A-axis servomotor 16. Mounted.

If, for example, 20000 pulse / 1rev encoders are used for the X-axis servo motor and the Z-axis servo motor, respectively, and the ball screw lead is, for example, 5 mm,
The amount of movement per pulse is 0.25 μmm, which enables high-precision measurement with a minimum resolution of 0.25 μmm without providing a linear scale on each axis.

On the other hand, the ball screw 1 is provided in the support column 15.
5a is provided, the vertically moving member 18 is arranged so as to be vertically movable by being screwed into the ball screw 15a, and the upper mandrel 14 is attached to the tip of the vertically moving member 18 via a cylindrical attachment portion. The ball screw 15a is linked to a manual rotation mechanism composed of a gear mechanism, a rotary shaft 19, a handle 20 and the like so as to be rotationally driven manually, and by rotating the handle 20, the ball screw 15a is rotated to move up and down. Member 1
8 That is, the upper mandrel 14 is moved up and down, and the measured gear G
Is set.

As shown in FIG. 2, the contact 6a of the displacement sensor 6 is arranged so as to be located on a horizontal center line passing through the centers of the upper and lower mandrels 14 in plan view.

FIG. 4 shows a block diagram of the control unit of the measuring machine. The control unit is mainly composed of a microcomputer, and includes a CPU 30, a ROM 31, a RAM 32, an input / output circuit 33, a printer 34, and a display device (for example, CRT) 3.
5, an operation switch (for example, keyboard) 36 is provided.
The A-axis servo motor 16 and the A-axis encoder 17 are connected to a servo driver 37, the X-axis servo motor 7 and the X-axis encoder 8 are connected to a servo driver 38, and the Z-axis servo motor 9 and the Z-axis encoder 10 are servo drivers. Three
9 is connected. The output side of the displacement sensor 6 is connected to the amplifier 29, and the servo drivers 37 to 39 and the amplifier 29 are connected to the input / output circuit 33. The ROM 31 stores the coordinate data of the tooth trace or tooth profile of the gear to be measured which is to be measured in advance.

Based on the program data stored in the ROM 31 in advance, the CPU 30 starts the measurement with the contact of the displacement sensor 6 positioned at the measurement start origin on the tooth surface of the gear to be measured, and stores it in the ROM 31. The XZ-axis moving mechanism 2 and the A-axis rotating mechanism 11 are driven on the basis of the coordinate data of the generated tooth trace or tooth profile to move the displacement sensor 6 along the coordinate of the tooth trace or tooth profile as designed for the gear. At that time, it operates to record the displacement data sent from the displacement sensor 6.

(1) Tooth streak measurement When the tooth streak measurement is performed using the gear measuring machine having the above configuration,
First, the center of the gear to be measured (spur gear) G is held horizontally between the lower mandrel 13 and the upper mandrel 14, and the gear to be measured G is accurately aligned and set on the A axis.

Next, by driving the A-axis servomotor 16,
The rotating column 12 is rotated by a slight angle so that the tooth groove of the measured gear G faces the displacement sensor 6, and then the X-axis servomotor 7 is driven to move the displacement sensor 6 forward in the X-axis direction.
As shown in FIG. 5, the tips of the contacts 6a of the displacement sensor 6 are positioned on the pitch circle in the tooth groove portion.

Next, the Z-axis servomotor 16 is driven to slightly move the displacement sensor 6 in the Z-axis direction, and the displacement sensor 6
The tip of the contactor 6a is positioned at the upper end or the lower end of the measured gear G in the thickness direction.

Subsequently, the A-axis servomotor 16 is driven to rotate the rotary column 12 in the clockwise direction in FIG. 5 by a slight angle, and stop when the tip of the contact 6a of the displacement sensor 6 contacts the tooth surface. , This position is the measurement start origin.
The output data of the displacement sensor 6 at this time is also the origin. The work procedure up to this point can be easily performed by the operator by sequentially displaying the guidance on the display 35.

After that, when the measurement start switch is turned on, the measuring machine starts automatic measurement under the control of the CPU 30, and drives the Z-axis servomotor 16 to move the displacement sensor 6 downward or upward along the Z-axis direction. As a result, the displacement sensor 6
The contactor 6a moves along the tooth trace of the gear to be measured G (in the direction of the arrow in FIG. 5). At this time, the displacement signal output from the displacement sensor 6 is taken into the CPU 30 as tooth trace measurement data, The displacement data is recorded in the RAM 32 while the child 6a moves to the other end of the measured gear G.

The displacement amount data output from the displacement sensor 6 directly becomes the tooth trace direction error, and if the data is zero, it means that the tooth trace is formed as designed. The measurement result is displayed on the display 35 or the printer 3
It will be printed out from 4. The tooth trace measurement is performed for each tooth of the gear.

On the other hand, in the case of measuring the tooth trace of the helical gear, up to the step of bringing the tip of the contact 6a of the displacement sensor 6 into contact with the tooth surface to set the measurement starting origin, the process is the same as in the case of the spur gear. In the step of actually collecting the measurement data, the Z-axis servo motor 16 is driven to move the displacement sensor 6 downward or upward along the Z-axis direction, and at the same time, the A-axis servo motor 16 is driven to rotate the column. While rotating the gear to be measured (helical gear) by the amount of the twist angle, simultaneous two-axis control is performed to measure the tooth trace.

Simultaneous two-axis control of Z-axis and A-axis at this time is as follows.
Coordinate data of the Z axis and the A axis are stored in advance in a ROM or the like according to the inclination of the tooth surface of the helical gear, and the Z axis and the A axis are controlled based on the data. And like above,
The contactor 6a of the displacement sensor 6 moves along the tooth trace of the helical gear, and the displacement signal output from the displacement sensor 6 at this time is taken into the CPU 30 as measurement data of the tooth trace and recorded in the memory. It In this case also, the displacement sensor 6
The displacement amount data output from the device directly becomes the tooth trace direction error.

(2) Tooth profile measurement To measure the tooth profile, first, the center of the gear to be measured (spur gear) G is held horizontally between the lower mandrel 13 and the upper mandrel 14, and the gear to be measured is placed on the A axis. Accurately align and set G. Next, the A-axis servo motor 16 is driven to rotate the rotary column 12 by a slight angle so that the tooth groove of the measured gear G faces the displacement sensor 6, and then the X-axis servo motor 7 is driven. The displacement sensor 6 is moved forward in the X-axis direction, and as shown in FIG. 6, the tip of the contact 6a of the displacement sensor 6 is positioned on the basic circle in the groove.

Subsequently, the A-axis servomotor 16 is driven to rotate the rotary column 12 clockwise by a slight angle in FIG. 6 and stop when the tip of the contact 6a of the displacement sensor 6 contacts the tooth surface. , This position is the measurement start origin.

In this state, the A-axis servomotor 16 is driven to rotate the rotary column 12 in the clockwise direction in FIG. 6 at a low speed, and at the same time, the X-axis servomotor 7 is driven to drive the displacement sensor 6
By moving backward to the left in Fig. 1 and simultaneously
The axis control is performed, and the contactor 6a of the displacement sensor 6 is moved in the toothbrush direction while being in contact with the tooth surface.

When the tooth profile of the gear G to be measured is formed by an involute curve, the coordinates of the involute curve are XY coordinates whose origin is the center of the basic circle of the gear, and x = r / cosα × cos (invα ), Y = r / cosα × sin (invα), Where r is the radius of the basic circle, in
vα is an involute function.

When the gear is rotated to set invα to zero, y = 0 and x = r / cosα can be expressed.

Therefore, if the data of the involute curve of the tooth profile of the gear to be measured is stored in advance in the RAM or the like,
By reading the data and performing simultaneous biaxial control of the A axis and the X axis, the contact 6a of the displacement sensor 6 can be accurately moved along the involute curve of a predetermined tooth profile. Also in this case, similarly to the above, the displacement amount data output from the displacement sensor 6 directly becomes the tooth profile direction error, and if the data is zero, the tooth profile is formed as designed.

Such tooth profile measurement is similarly performed at a plurality of positions in the tooth width direction of each tooth, and is similarly performed for each tooth of the gear.

As described above, after the position of the contact 6a of the displacement sensor 6 is set to the measurement starting origin, the displacement sensor 6 is automatically moved along the Z axis in the spur gear to easily eliminate the tooth trace error. With a helical gear, the displacement sensor 6 is moved along the Z axis while the gear to be measured is
By rotating it on the shaft, the tooth trace error can be easily measured. In the tooth profile measurement, the tooth profile error can be easily measured by automatically moving the displacement sensor 6 along the X axis and rotating the measured gear on the A axis.

[Brief description of drawings]

FIG. 1 is a front view of a gear measuring machine showing an embodiment of the present invention.

FIG. 2 is a plan view of the gear measuring machine.

FIG. 3 is a right side view of the gear measuring machine.

FIG. 4 is a block diagram of a control unit of the measuring machine.

FIG. 5 is an explanatory plan view showing measurement of gear tooth traces.

FIG. 6 is an explanatory plan view showing tooth profile measurement of a gear.

[Explanation of symbols]

 1-Platform 2-XZ axis movement mechanism 5-Movement head 6-Displacement sensor 11-A axis rotation mechanism

Claims (3)

[Claims] 1. An XZ-axis moving mechanism provided with a moving head which is arranged on a surface plate and is movable in the X-axis and Z-axis directions, and a displacement signal which is fixed to the moving head and corresponds to the movement of a contact. An A-axis that positions the center of the rotating column on the X-axis, through which the displacement sensor that outputs and the contact of the displacement sensor that is arranged on the surface plate pass, and that horizontally supports the gear to be measured on the central axis of the rotating column. A method for measuring a gear using a gear measuring machine equipped with a rotating mechanism, wherein a tip of a contact of the displacement sensor is placed at a measurement starting origin in a tooth groove of the gear to be measured to contact the tooth surface. In this state, the displacement sensor is moved along the Z axis by the XZ axis moving mechanism, or the displacement sensor is moved along the Z axis by the XZ axis moving mechanism and is measured by the A axis rotating mechanism. When the gear is rotated on the A axis, the change output from the displacement sensor Captures the signal, gear measurement method and performing tooth trace measured based on the displacement data. 2. An XZ-axis moving mechanism provided on a surface plate and provided with a moving head movable in the X-axis and Z-axis directions, and a displacement signal fixed to the moving head and corresponding to a movement of a contactor. An A-axis that positions the center of the rotating column on the X-axis, through which the displacement sensor that outputs and the contact of the displacement sensor that is arranged on the surface plate pass, and that horizontally supports the gear to be measured on the central axis of the rotating column. A rotating mechanism, and a gear measuring method using a gear measuring machine provided with, wherein the tip of the contact of the displacement sensor is placed at the measurement starting origin in the tooth groove of the gear to be measured and contacts the tooth surface. In this state, the displacement sensor is moved along the X-axis by the XZ-axis moving mechanism and the gear to be measured is rotated on the A-axis by the A-axis rotating mechanism, and a displacement signal output from the displacement sensor is output. To measure the tooth profile based on the displacement data. Gear measurement method according to claim. 3. An XZ-axis moving mechanism provided on a surface plate and having a moving head movable in the X-axis and Z-axis directions, and a displacement signal fixed to the moving head and corresponding to a movement of a contactor. A displacement sensor for outputting, an X-axis servomotor provided with the XZ-axis moving mechanism and having an encoder for moving the moving head in the X-axis direction, and an encoder provided in the XZ-axis moving mechanism for moving the moving head in the Z-axis direction Z-axis servo motor with a center, and the center of the rotating column is located on the X-axis, which is arranged on the surface plate and through which the contact of the displacement sensor passes, and the gear to be measured is horizontally placed on the central axis of the rotating column. An A-axis rotating mechanism that supports, an A-axis servomotor with an encoder that rotates a gear to be measured supported on a rotation column of the A-axis rotating mechanism around the A-axis, and a contact of the displacement sensor to a gear to be measured. In contact with The XZ axis moving mechanism is controlled to drive the displacement sensor to X
The gear to be measured is rotated on the A-axis by moving the A-axis rotating mechanism by controlling the A-axis rotating mechanism, and based on the displacement signal output from the displacement sensor, the tooth profile or the tooth trace of the gear is determined. A gear measuring machine, comprising: measurement control means for measuring.