JPH0771950A - Method for measuring gear shape - Google Patents

Abstract

PURPOSE:To enable measurements to be easily made in a short time using a gear shape measuring method in which the finished shape of a machined gear is measured. CONSTITUTION:A photosensor 24 is secured in a position a distance R away from the center O of a gear 3, and the gear 3 is rotated counterclockwise about the center O form the position in the figure. During rotation of the gear 3, a detection signal is switched from its on to off state when the photosensor 24 approaches the portion of the gear 31 at point P1. At that time, a numerical control system recognizes the point P1 as the crossing point of the left end side of the gear 31 with a circle S, and stores its angular position theta1 in memory. When the photosensor 21 approaches the portion of the gear 31 at point Q1, the detection signal is switched from its off to on state. At that time, the numerical control system recognizes the point Q1 as the crossing point of the right end side of the gear 31 with the circle S and stores its angular position theta2 in memory. Then, the points P1-P8 and Q1-P8 are located by similar procedures, whereby, the shape of the gear 3 is measured.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gear shape measuring method for measuring a finished shape of a processed gear, and more particularly to a gear shape measuring method for measuring a finished shape of a processed gear by using a numerical controller.

[0002]

2. Description of the Related Art Conventionally, measurement of a finished shape of a gear machined by using a numerical control device has been performed by using a skip cutting feed which is one of the functions of the numerical control device.

FIG. 4 is a diagram showing a conventional gear shape measuring method using skip cutting feed. The gear 41 is, for example, 8
It is a work in which the teeth 411 to 418 are formed, and the rotation thereof is controlled around the center point O. The sensor 42 is a touch-type or optical-type limit sensor, and is fixed at a position at a predetermined distance r from the center point O of the gear 41. This distance r
Is a position near the middle of the teeth 411 to 418 of the gear 41. The sensor 42 turns on the detection signal when an obstacle is detected, and turns it off when the obstacle is not detected.

In the illustrated state, when the gear 41 is first rotated counterclockwise, the sensor 42 is rotated by an angle θ ₀₁ , that is, a point P _{11 at a} distance r from the center point 0 of the left end side of the tooth 411. Detects a fault with and turns on the detection signal. By the input of this detection signal, the numerical control unit causes the point P
₁₁ positions are detected. After that, the teeth 412 to 4 are similarly processed.
The positions of points P _{12 to} P _{18 on} the left side edge of ₁₈ are detected.

When the detection of the positions P _{12 to} P ₁₈ is completed, the gear 41 is rotated clockwise this time, and the positions of the points Q _{12 to} Q _{18 on} the right side edges of the teeth 412 to 418 are determined by the same procedure as described above. To detect.

[0006]

However, in such a conventional measuring method, it was necessary to rotate the gear 41 twice in order to detect the positions of both side edges of the teeth 412 to 418. For this reason, the work of measuring the shape takes time and effort.

The present invention has been made in view of the above points, and an object thereof is to provide a gear shape measuring method which is simple and can be performed in a short time.

[0008]

In order to solve the above problems, the present invention provides a gear shape measuring method for measuring a finished shape of a processed gear, including gear rotation control means for rotating the gear in a fixed direction, A sensor that is fixed at a position where a tooth portion of the gear passes when the gear rotates, and outputs a different signal when an obstacle is detected and when the obstacle is not detected; and a rotation position of the gear when the signal changes. And a rotational position detecting means for detecting the position of the gear.

[0009]

The sensor, which outputs different signals when an obstacle is detected and when it is not detected, is fixed at a position where a tooth portion of the gear passes when the gear rotates, and the gear rotation control means moves the gear in a fixed direction. Rotate. Then, the rotational position of the gear when the sensor signal changes is detected by the rotational position detecting means.

As a result, the passing position of the sensor on both side edges of each tooth of the gear is detected only by rotation in one direction.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 2 is a schematic configuration diagram of hardware inside the CNC for implementing the present invention. The processor 11 is R
The entire numerical control device is controlled according to the system program stored in the OM 12. The ROM 12 is an EPROM
Or EEPROM is used. RAM13 has SRA
M or the like is used to store various data or input / output signals.

A CMOS (not shown) backed up by a battery is used in the non-volatile memory 14, and parameters such as a pitch error correction amount and a tool correction amount to be held even after the power is turned off are stored. Further, the nonvolatile memory 14 stores a program for executing the gear shape measuring method according to the present embodiment read from a floppy disk or the like (not shown). Further, the non-volatile memory 14 stores gear shape measurement data.

The graphic control circuit 15 converts the digital signal into a signal for display and gives it to the display device 16. A CRT or a liquid crystal display device is used as the display device 16. The display device 16 displays the shape, the machining conditions, the generated machining program, and the like when the machining program is created interactively.

A machining program can be created by inputting data according to the contents displayed on the display device 16 (interactive data input screen). A graphic representing the meaning of the data is displayed at the top of the screen, and the type of data to be input is displayed at the bottom. Further, the work or data that can be received on the screen is displayed on the screen in a menu format. Which item in the menu is selected is selected by pressing the soft key 23 below the menu, and the meaning of the soft key 23 changes for each screen.

The keyboard 17 is composed of symbolic keys, numerical keys, etc., and necessary figures and data are input using these keys. PMC (programmable machine
The controller) 22 receives the M function signal and the like via the bus 21, processes it by a sequence program, outputs an output signal, and controls the machine tool 20. In addition, PMC22
Receives an input signal from the machine side, processes it by a sequence program, and transfers a necessary input signal to the processor 11 via the bus 21.

The axis control circuit 18 receives the axis movement command from the processor 11 and outputs the axis command to the servo amplifier 19. The servo amplifier 19 receives the movement command and drives the servo motor of the machine tool 20.

The machine tool 20 is provided with an optical sensor 24 for measuring the gear shape. The detection signal of the optical sensor 24 is input to the numerical controller via the bus 21.
FIG. 3 is a diagram showing the configuration of the measuring unit on the machine tool 20 side for performing the gear shape measuring method of this embodiment. The processed gear 3 is fixed to, for example, the Z axis and is rotationally controlled in a fixed direction by a skip cutting function. An optical sensor 24 is provided near the rotating gear 3. Optical sensor 2
Reference numeral 4 includes a light emitting section 24a and a light receiving section 24b. The light emitting portion 24a and the light receiving portion 24b are fixed in positions so as to sandwich the gear 3 from above and below and to face each other. Light 24c is output from the light emitting unit 24a, and if there is no obstacle, the light 24c is received by the light receiving unit 24.
The light is received at b. When the light 24c is received,
The light receiving unit 24b sends a detection signal to the numerical controller. The numerical controller constantly monitors the on / off switching of the detection signal, and controls the rotation of the gear 3 as described later according to the timing.

FIG. 1 is a plan view for explaining a specific procedure of the gear shape measuring method of this embodiment. The optical sensor 24 is fixed at a position at a distance R from the center O of the gear 3. Here, it is assumed that the gear 3 has eight teeth 31 to 38, and is controlled to rotate counterclockwise about the central portion O from the position shown in the drawing. Therefore, the optical sensor 24 moves on the circumference of the circle S having the radius R relative to the gear 3.

The rotation of the gear 3 is performed by using the skip cutting feed function. For this reason, first gear 3
Is rotationally controlled so that the optical sensor 24 comes to the position of the angle C ₁ from the movement start point. This angle C ₁ is determined by the optical sensor 2
The angle θ at which 4 comes to the intersection P ₁ of the left side of the tooth 31 and the circle S
It is set to be reasonably larger than ₁ .

During the rotation of the gear 3, the optical sensor 23 moves the teeth 3
When the point P ₁ of ₁ is reached, the detection signal switches from on to off. At this time, the numerical controller stops the rotation of the gear 3 at one end, recognizes that the stop point P ₁ is the intersection of the left side edge of the tooth 31 and the circle S, and determines the angular position θ ₁ thereof.
Are stored in the nonvolatile memory 14.

Then, the gear 3 is rotated again. This time, the rotation of the optical sensor 24 is controlled so as to come to the position of the angle C ₂ from the rotation restart position. When the optical sensor 24 approaches the portion of the tooth 31 at the point Q ₁ during this process, the detection signal is switched from off to on. At this time, the numerical controller stops the rotation of the gear 3 again, recognizes that this stop point Q ₁ is the intersection of the right side edge of the tooth 31 and the circle S, and the angular position θ ₂ is stored in the nonvolatile memory. Store in 14.

Thus, thereafter, the tooth 3 is subjected to the same procedure.
Intersection P between each edge of 2 to 38 and the circle S ₂~ P₈, And Q
₂~ Q₈The angular position of is detected. Then a gear like this
An example of a program for performing measurement work is shown.

G00 C ₀ ; G31 C ₁ T0; G31 C ₂ T1; G31 C ₃ T0; G31 C ₄ T1; C ₀ is the angular position of the gear 1 at the start of shape measurement. G31 is a command to execute a skip cut, respectively angles _{C 1, C 2, C 3} , an instruction to move to ....
Further, T is a command for the change of the detection signal of the sensor 23, T0 is a command to stop the rotation and detect the position when the detection signal changes from OFF to ON, while T1 is to change the detection signal from ON. It is an instruction to stop the rotation and detect the position when it is turned off.

By performing such programming, the gear shape measurement as shown in FIG. 1 is executed. As described above, in this embodiment, the gear 3 is rotated to alternately detect the angular position when the detection signal of the optical sensor 24 changes from on to off and when it changes from off to on. Therefore, the shape can be accurately measured only by rotating the gear 3 once in a fixed direction.

In the present embodiment, the positions of the points P _{2 to} P ₈ and Q _{2 to} Q ₈ are detected by angles, but the recognition may be performed by the normal coordinate position. Further, although the optical sensor 24 is used as the sensor in this embodiment, a touch sensor may be used.

[0026]

As described above, according to the present invention, the rotational position of the gear when the signal of the sensor changes is detected, so that the passing position of the sensor on both side edges of each tooth of the gear is unidirectional. Accurately detected only by rotating.

Therefore, the gear shape can be easily measured in a short time.

[Brief description of drawings]

FIG. 1 is a plan view illustrating a specific procedure of a gear shape measuring method according to this embodiment.

FIG. 2 is a schematic configuration diagram of hardware inside a CNC for implementing the present invention.

FIG. 3 is a diagram showing a configuration of a measuring unit on the machine tool side for performing the gear shape measuring method of the present embodiment.

FIG. 4 is a diagram showing a gear shape measuring method using a conventional skip cutting feed.

[Explanation of symbols]

 3 gear 11 processor 20 machine tool 24 optical sensor 31-38 teeth

Claims (3)

[Claims] 1. A gear shape measuring method for measuring a finished shape of a processed gear, wherein a gear rotation control means for rotating the gear in a fixed direction, and a tooth portion of the gear passes when the gear rotates. A sensor that is fixed at a position and that outputs a different signal when an obstacle is sensed and when it is not sensed; and a rotational position detection unit that detects the rotational position of the gear when the signal changes, Gear shape measurement method. 2. The gear shape measuring method according to claim 1, wherein the sensor is an optical sensor. 3. The gear shape measuring method according to claim 1, wherein the gear rotation control means is configured to control the rotation of the gear by a skip cutting function.