JP2611630B2 - Detachment method and detachment jig for detector in length measuring device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical or magnetic length measuring apparatus, and more particularly to an exchange method for easily removing a detection unit from a main body of a scale unit, and an exchange method applied to the method. It is about tools.

[0002]

2. Description of the Related Art An optical length measuring device 1 shown in FIG. 2 will be described as an example of a length measuring device. The length measuring device 1 includes a scale unit 2 which is a mechanism for detecting a relative movement of two objects to be measured, and an arithmetic unit (not shown) for processing a signal output from the scale unit 2.

[0003] The scale unit 2 of the length measuring device has a main scale 3 in which a scale for measuring the length or detecting the origin position is formed of a metal thin film on a glass plate. The main skeleton 3 is mounted in a case 4, which constitutes a main body 5 of the scale unit 2.

[0004] Inside the main body 5, a detection unit 6 of the scale unit 2 is movably provided. Detector 6
The holder 7, which is a base, has a substantially U-shaped cross section orthogonal to the longitudinal direction of the main scale 3, and is mounted with the main scale 3 sandwiched between grooves. The holder 7 is provided with a plurality of bearings 8 as guide means for the main scale 3 and the case 4. Therefore, the detection unit 6 is guided in the case 4 so as to be movable with respect to the main scale 3 while maintaining respective distances between the main scale 3 and the inner surface of the case 4 at predetermined intervals.

A light source 9 is provided on one of the mounting portions of the holder 7, and an index scale 1 is provided on the other.
0 and a light receiving unit 11 are provided. Therefore, the index scale 10 is disposed close to the main scale 3, and the light source 9 and the light receiving unit 1 are located between the scales 10 and 3.
1 is arranged.

The index scale 10 is formed with a slit inclined with respect to the scale of the main scale 3. The moire fringes formed by the scales and the slits are detected as electric signals by receiving the light emitted from the light source 9 of the detecting unit 6 through the scales 3 and 10 at the light receiving unit 11.

Further, this electric signal is processed by an amplifying device, an interpolation circuit, a waveform shaping circuit and the like (not shown), and is output as two signals having a phase difference of 90 ° and an origin position signal.

The signal output from the detection unit 6 of the scale unit 2 is processed by a control unit (not shown), and the movement amount and the movement direction of the measured object are calculated. This operation unit is
When provided independently of the control unit of the machine tool,
There is a case where the detection result of the length measuring device incorporated in the control unit of the machine tool is used for feedback control.

[0009]

In the length measuring device 1, when the inside of the main body 5 of the scale unit 2 is cleaned, or when the detection unit 6 of the scale unit 2 breaks down, the detection unit 6 is used. It is necessary to remove it from the main body 5.

As described above, the detection unit 6 is in contact with the inner surface of the case 4 and the main scale 3 with the bearing 8. Further, the detection unit 6 itself is formed of precision components. Therefore, the detecting section 6 having such a configuration is connected to the main body section 5.
Removing and re-attaching from was a very cumbersome task that required careful attention. Further, when the detector 6 is replaced, it is necessary to check and adjust the waveform output by the detector 6 after the replacement, and the operation is also troublesome.

More specifically, for example, in a machine tool, there is a case where a workpiece needs to be fixed to a table and a required one must be selected from a plurality of spindle heads for processing.

In such a case, since it is necessary to provide the scale unit 2 for each spindle head, two sets of scale units 2 are required, and each scale unit 2 is integrated with the driving part of each head. There is a problem that the calculation unit of the scale unit 2 is required independently for each scale unit 2.

[0013] Even if two sets of the main unit 5 of the scale unit 2 are prepared and one detecting unit 6 is replaced and used, as described above, the replacement is difficult. If it is included, the work time for replacement becomes too long.
A method of alternately using the main bodies 5 of the set could not be adopted.

[0014] It is an object of the present invention to facilitate replacement of a detection unit in a length measuring device and to enable a single detection unit to handle a plurality of main units even when a spindle head of a machine tool is replaced. And

[0015]

According to a first aspect of the present invention, there is provided a method for attaching and detaching a detecting section in a length measuring apparatus, comprising: a main body in which a scale provided with a scale for position reading is housed in a case; And a detecting unit that converts a relative movement amount of the unit with respect to the scale into an electric signal and outputs the electric signal, and further includes a relative movement of the scale and the detecting unit based on a detection signal from the scale unit. Applied to a length measuring device equipped with a calculation unit for calculating the quantity,
A side end of the case of the main body is opened, and a detachment jig for movably storing the detection unit is attached to the side end similarly to the main body, and the main body 5 is attached to the main body 5 through the detachment jig. On the other hand, the detection unit is detached.

According to a second aspect of the present invention, there is provided a jig for attaching and detaching the detecting section, wherein a main body having a scale on which a scale for reading a position is formed is housed in a case, and an amount of relative movement of the main body with respect to the scale. A scale unit comprising a detection unit for converting the electric signal into an electric signal and outputting the electric signal, and further comprising a calculation unit for calculating a relative movement amount of the scale and the detection unit based on a detection signal from the scale unit. Applied to a length measuring device, having a guide structure of a detection unit for movably storing the detection unit similarly to the main unit, being detachably attached to a side end of the main unit which is made openable. Features.

[0017]

The side end of the main body is opened and a detachable jig is attached to the side end. The detection unit in the main body is moved into the attachment / detachment jig. The attachment / detachment jig in which the detection unit is housed is detached from the main body, and attached to the open side end of another main body. The detector is moved into the main body.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIG.
The scale unit 22 of the length measuring device 21 shown in FIGS. 1A and 1B has almost the same configuration as the above-described conventional scale unit 2. What is different from the conventional case 2
4 is that the side end portion can be opened and closed by the lid member 30. When the lid member 30 is removed, the cross-sectional shape of the inner surface of the case 24 and the side end surface of the main scale 3 can be seen from the open end of the case 24.

The case 2 opened by removing the lid member 30
As shown in FIGS. 1C and 1D, a detachable jig 4 for attaching and detaching the detector 6 to and from the main body 25 is provided on the side end of the main body 25.
0 is detachably connected.

The attachment jig 40 has the same internal shape and structure as those of the end of the main body 25.
Accordingly, in a state where the attachment / detachment jig 40 and the main body 25 are connected, the length of the scale unit 22 is apparently elongated.

Next, a method of attaching and detaching the detecting section 6 in the length measuring device using such an attaching and detaching jig 40 will be described.

The cover member 30 of the case 24 of the main body 25 shown in FIG. 1A is removed, and the side end of the case 24 is opened as shown in FIG. 1B.

As shown in FIG. 1C, a detachable jig 40
Is connected to the case 24, and the detection unit 6 is slid and housed in the attachment / detachment jig 40.

As shown in FIG. 1D, a detachable jig 40
Is removed from the case 24, and the removal of the detection unit 6 from the main body 25 is completed.

By repeating the above operation in reverse, the detection unit 6 can be mounted again in the case 24. Alternatively, the detection unit 6 can be mounted in a case of another main body.

As described above, the following effects can be obtained by using the detachable jig 40. First, when it is necessary to clean the inside of the main body 25 due to oil or water droplets (condensation) on the surface of the main scale 3 or dust adheres thereto, it is necessary to replace the detection unit 6 itself. In such a case, if such a detachable jig 40 is used, the detachment and reattachment of the detection unit 6 becomes extremely easy.

In addition, when the detector 6 is replaced, it is necessary to readjust the output waveform with an oscilloscope or the like and readjust it. However, the internal structure of the attachment / detachment jig 40 is almost the same as that of the main body 25. Therefore, the displacement of the output waveform due to the replacement of the detection unit 6 hardly occurs. Therefore, it is only necessary to check the output waveform, and the adjustment work becomes easy,
In some cases, the adjustment work itself becomes unnecessary.

Next, a procedure for exchanging the detecting section 6 of the length measuring device 21 using the detachable jig 40 when the spindle head of the machine tool is exchanged and used will be described. The main unit 25 of the scale unit 22 is attached to the spindle head, and the detection unit 6 is attached to the base of the machine. The detachable jig 40 is attached to the open end of the case 24 of the main body 25. Move the spindle head relative to the base. The detector 6 on the base moves relatively to the main body 25 and is stored in the attachment / detachment jig 40.

In this state, the connection between the attachment / detachment jig 40 and the case 24 of the main body 25 is released, and the spindle head is moved together with the main body 25 to a predetermined standby position. The detection unit 6 on the base side is in a state of being housed in the attachment / detachment jig 40.

Next, another spindle head to which another main body 25 has been attached in advance and has been on standby is set to the actual working position. That is, the spindle head is moved with respect to the base, and the opened side end of the main body 25 is connected to the attachment / detachment jig 40. Further, by moving the spindle head in a predetermined direction with respect to the base, the detachment jig 4
The detection unit 6 is transferred from inside the main unit 25 to the other main unit 25. Then, the opened side end of the main body 25 is closed by the lid member 30, and the detecting unit 6 in the length measuring device 21 of the spindle head is closed.
Is completed.

In the example described above, a total of two main units 25 are required for each head. However, since only one detection unit 6 is required, the control unit of the length measuring device 21 may be one channel and one control unit. Can be used in common.

In particular, when the control unit of the machine tool moves the spindle head relative to the workpiece based on the data read by the length measuring device 21, the single control unit on the length measuring device 21 side is controlled by the injection molding machine. Alternatively, since it can be directly incorporated into the control unit of the machine tool, the overall configuration is simplified and advantageous.

Further, as long as the main body 25 is accurately attached to each spindle head without removing the detection unit 6 from the base, the relative positional relationship between the detection unit 6 and the main body 25 is determined by the spindle head. It does not change even if it is replaced. Therefore, the operation of checking or adjusting the output waveform of the detection unit 6 is simplified, and may be unnecessary in some cases.

Conversely, when the detector 6 is attached to each of a plurality of spindle heads, the number of detectors 6 is plural in accordance with the number of spindle heads. Become. However, the main body 25 is 1
It only needs an individual. Further, the attachment / detachment jig 40 serves as a cover for the detection unit 6, and each detection unit 6 attached to each spindle head.
Are protected by the attachment / detachment jig 40, respectively.

[0035]

According to the method for attaching and detaching the detecting section of the length measuring device and the attaching / detaching jig according to the present invention, the attaching / detaching jig capable of movably storing the detecting section is attached to the open side end of the main body, Since the detection unit is attached and detached via the attachment / detachment jig, there is an effect that the detection unit can be easily replaced.

Also, an industrial machine having a plurality of moving parts whose positions are determined by the length measuring device, such as a machine tool which uses a plurality of spindle heads positioned by the length measuring device by selecting and replacing them as necessary Has conventionally required a length measuring device corresponding to the number of spindle heads. However, according to the present invention, only the main unit is provided for each head, the detecting unit that slides on the main unit is made common, and the common detecting unit is configured to be attached to and detached from each main unit in accordance with the exchange of the head. Can be.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an embodiment of the present invention.

FIG. 2 is a sectional view showing a conventional length measuring device.

[Explanation of symbols]

 Reference Signs List 3 Main scale 6 Detector 21 Length measuring device 22 Scale unit 24 Case 25 Main body 40 Detachment jig

Claims (2)

(57) [Claims] 1. A main unit comprising a scale in which a scale for position reading is formed in a case, and a detecting unit for converting a relative movement amount of the main unit with respect to the scale into an electric signal and outputting the electric signal. Is applied to a length measuring device further comprising a calculation unit that calculates a relative movement amount of the scale and the detection unit based on a detection signal from the scale unit, In the attaching / detaching method of the attaching / detaching unit, a side end of a case of the main body is opened, and a detachable jig for movably housing the detecting unit is attached to the side end similarly to the main body. And a method of attaching and detaching the detecting section in the length measuring device for attaching and detaching the detecting section to and from the main body section via the attaching and detaching jig. 2. A system comprising: a main body in which a scale on which a scale for reading a position is formed is housed in a case; and a detector for converting a relative movement amount of the main body with respect to the scale into an electric signal and outputting the electric signal. Is applied to a length measuring device further comprising a calculation unit that calculates a relative movement amount of the scale and the detection unit based on a detection signal from the scale unit, In the desorption jig of the detection unit for detaching the detection unit,
A length measuring device having a guide structure for a detection unit that movably stores the detection unit similarly to the main unit, and is detachably attached to a side end of the main unit that is made openable. Detachment jig for the detector.