JPS6227844Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a measuring device used for measuring the thread groove pitch of a ball screw shaft.

Traditionally, when measuring the pitch of a groove in a long object to be measured, such as the pitch of a thread groove on a ball screw shaft, manual measurement is the main method; There was a need for a device that could measure automatically.

An object of the present invention is to provide a measuring device that can automatically measure the groove pitch of a screw.

Another object of the present invention is to measure the groove pitch of a thread by bringing the probe into contact with the groove only when necessary, thereby eliminating measurement errors caused by wear of the probe and speeding up measurement work. The goal is to provide a measuring device that can do this.

For this reason, the measuring device of the present invention has a detection unit equipped with a slidable measuring tip that is moved along a guide rail by a unit drive mechanism, and a spring that biases the measuring tip toward the object to be measured. The measuring head is brought into contact with and separated from the object to be measured by a measuring head drive mechanism consisting of a measuring head advancing/retracting member that is movable in the sliding direction of the measuring head and releasably engaged with the measuring head. With the probe drive mechanism separating the probe from the object to be measured, the unit drive mechanism moves the detection unit to feed the probe a predetermined amount in the axial direction of the object to be measured, and connects the detection unit and the unit drive mechanism. is disconnected by the clutch to make the detection unit freely movable, and then the probe is brought into contact with the groove of the object to be measured by the probe drive mechanism, and the detection unit is moved freely to fit the probe into the groove. The groove pitch is measured by detecting the amount of movement of the detection unit at this time using a movement amount detection means consisting of a laser oscillator, an interferometer, or the like.

Hereinafter, one embodiment of the present invention will be described based on the drawings.

1 and 2 show the overall structure of this embodiment, FIGS. 3 to 5 show enlarged views of the detection unit used in this embodiment, and FIGS. The figure shows an enlarged view of the support block unit used in this embodiment.

In FIGS. 1 and 2, a prismatic guide rail 2 is arranged along the longitudinal direction on a table 1 serving as the main body of the apparatus, and a detection unit 3 is movably supported on this guide rail 2. Also,
A motor 4 as a unit drive mechanism is provided at one end of the table 1, the right end in FIG. . A rotary encoder 7 as a drive amount detection mechanism is provided at the other end of the table 1, the left end in FIG. 1, and a pulley 8 is fixed to the output shaft of the rotary encoder 7. A wire 9 is routed between the pulley 8 and the pulley 6, and both ends of the wire 9 are fixed to the detection unit 3. As a result, when the motor 4 is driven with the clutch 5 in the ON state, that is, in the contact state, the wire 9
The detection unit 3 is driven via the rotary encoder 7, and the amount of this drive is read by the rotary encoder 7. Also, the output of the rotary encoder 7 is
The measurement and control circuit (not shown) is transmitted to the power supply circuit of the motor 4 and the clutch 5, and the detection unit 3 detects a predetermined amount, e.g.
When driven by a pitch or several pitches,
The power supply circuit is turned off to allow the detection unit 3 to move freely.

A curtain type power supply rail 11 is provided at the rear of the table 1 via a support 10, and power is supplied to the detection unit 3, measurement signals are transmitted, etc. via a cable 12 supported by the power supply rail 11. It's becoming like that.

A laser oscillator 12 is provided at a higher position on the left end of the table 1, and this laser oscillator 1
The laser beam from the detector 2 is emitted through an interferometer 13 provided on the table 1 toward a reflecting mirror 14 provided in the detection unit 3.
By measuring the distance from the detection unit 2, the amount of movement of the detection unit 3 can be accurately measured. The laser oscillator 12, the interferometer 13, and the reflecting mirror 14 constitute a movement amount detecting means 15. In addition, a scale 16 is provided on the front surface of the guide rail 2.
A pointer 17 is provided on the front side of the detection unit 3, and these scales 16
The approximate position of the detection unit 3 can also be detected using the pointer 17.

A block guide rail 18 is provided at the lower front of the guide rail 2, and a support block unit 21 is movably attached to a T-groove 19 provided along the longitudinal direction of the rail 18 via a lock screw 20. ing. The support block units 21 are provided at a plurality of locations on the rail 18, and a long object 22 to be measured, such as a ball screw shaft, is supported on these support block units 21.

As shown enlarged in FIGS. 3 to 5, the detection unit 3 includes a unit base 23, and on the lower surface of the unit base 23 there are two Pairs of rollers 24 are provided in contact with each corner of the surface, one pair on the left and right for each two corners, a total of four pairs, and these rollers 24 allow the detection unit 3 to move smoothly on the guide rail 2. It is now possible to move. Further, both ends of the wire 9 are attached to both rear side surfaces of the unit base 23 via attachment fittings 25 and 26, and a reflecting mirror 14 is attached to the front portion of the upper surface of the left end.

A spindle-shaped probe 27 is supported within the center of the unit base 23 so as to be movable in the axial direction. One end, the front part, of this probe 27 protrudes from the unit base 23, and a measurement tip 28 having a spherical tip is fixed thereto, and the other end, the rear part, is used for measuring the amount of forward and backward movement of the probe 27. The tip of a spindle 30 of a linear encoder 29 as a mechanism is in contact with it. This spindle 30 is connected to the linear encoder 2 by a spring (not shown).
9 is biased to protrude from the main body of the probe 9, and is always in contact with the rear part of the probe 27.
It is designed to move by following the movement of. Further, a compression coil spring 31 is interposed between the probe 27 and the unit base 23 as a biasing means.
This spring 31 allows the measuring element 27 to move to the measuring tip 28.
The side is biased in the direction in which it protrudes, that is, in the direction in which it comes into contact with the object to be measured 22.

As shown in FIG. 5, the probe 27 has a pin 32 protruding from it. It is inserted into a notched groove 35 provided on the lower surface of the notched groove 35, and is brought into contact with the end surface of the notched groove 35 by the biasing force of the compression coil spring 31. The nut member 34 is screwed onto a feed screw shaft 36, which is rotatably supported by a pair of support plates 37 erected on the unit base 23, and is connected to a small-sized screw through a gear train 38. It is designed to be rotated by a geared motor 39. As a result, the nut member 34 is moved forward and backward by the drive of the small geared motor 39 via the gear train 38 and the feed screw shaft 36, and therefore the measuring head 2
7 moves forward and backward following the nut member 34 by the biasing force of the compression coil spring 31.
At this time, the nut member 34 as a measuring element advancing/retracting member for advancing and retracting the measuring element 27 is connected to the nut member 3.
Rotation is prevented by the engagement between the notch groove 35 of No. 4 and the pin 33. In addition, these compression coil springs 31, pins 32, nut members 34, and feed screw shafts 3
6, a gear train 38 and a small geared motor 39 constitute a probe drive mechanism 40.

A first limit switch 41 is provided on the lower surface of the nut member 34, an operating piece of the limit switch 41 is in contact with a side surface of a pin 32, and the pin 32 is in contact with an end surface of the notch groove 35 of the nut member 34. When the pin 32 is separated from the nut member 34, the pin 32 is turned off. This limit switch 41 is connected to the power supply circuit of the small geared motor 39,
When the motor 39 is turned off, the motor 39 is stopped. Further, a pair of actuation pins 42 and 43 are provided upright on the upper surface of the nut member 34, and these actuation pins 42 and 43 are able to come into contact with actuation pieces of second and third limit switches 44 and 45. . These limit switches 44, 45 are mounted on a bracket 46 erected on the unit base 23, and are used to regulate the retraction and advancement of the nut member 34.

A circuit board 48 is attached to the upper part of the pair of support plates 37 via a mounting plate 47. The circuit board 48 supports the first to third limit switches 41,
A small geared motor 39 can be controlled by signals 44 and 45 and an external signal.

As shown enlarged in FIGS. 6 and 7, the support block unit 21 includes a block base 51, and lock screws 20 are provided on both sides of the block base 51 as described above. The block base 51 is attached to the T-slot 19 of the block guide rail 18 by a lock screw 20. Further, a slide table 52 is slidably mounted on the block base 51 by dovetail fitting, and a slide table drive screw 54 is rotatably attached to the front part of the slide table 52 via a mounting plate 53. Supported. The inner end threaded portion of the drive screw 54 is fixed to the block base 51 and screwed into the female threaded member 55, and a knob 56 is fixed to the outer end. As a result, by operating the knob 56 and rotating the drive screw 54, the sliding base 52 can be moved.
can be moved forward and backward relative to the block base 51.

A fixed block 57 fixed to the rear part of the sliding table 52 and a movable block 58 movable on the sliding table 52 are provided on the sliding table 52.
These fixed blocks 57 and movable blocks 58
Beveled surfaces 59 and 60, which together form a V-shape, are formed on the upper portions of the surfaces facing each other. Further, the fixed block 57 is formed in a U-shape when viewed from above, and the movable block 58 is shaped so that it can fit inside this U-shape.

The lower surface of the movable block 58 is connected to the moving nut 6.
1 is rotatably engaged with a support shaft 62 erected,
The moving nut 61 is screwed onto a block drive screw 63 and is guided in a long groove 64 formed in the sliding base 52. The block drive screw 63 is rotatably supported by the slide table 52, and one end thereof projects forward of the slide table 52, and a knob 65 is fixed to this protrusion.
A rod-shaped handle 66 can be attached to this knob 65 if necessary.
This allows the knob 65 to be rotated.

A column 68 is attached to the movable block 58 so that its height can be adjusted using a fixing screw 67. A support member 70 whose mounting position can be adjusted using a long groove 69 is attached to the upper end of this column 68. A clamp screw 71 is screwed into the tip. With this clamp screw 71, the beveled surfaces 59, 6 of the fixed block 57 and the movable block 58 are fixed.
The object to be measured 22 can be clamped by pressing the upper surface of the object to be measured 22 placed on the 0.

Note that reference numerals 73 in FIGS. 1 and 2 indicate stoppers of the detection unit 3 provided on both ends of the guide rail 2.

Next, the operation of this embodiment will be explained.

First, before measuring the object to be measured 22, calibrate each measuring device, that is, the rotary encoder 7, the laser oscillator 12, the linear encoder 29, etc., and measure the measurement chip 28 that matches the thread groove shape of the object to be measured 22. Attach it to child 27, and after this,
The support block unit 2 is placed in a position that is least affected by deflection considering the shape of the object 22 to be measured.
1 and fix it with the lock screw 20.

Next, the object to be measured 22 is placed on the fixed block 57 and movable block 58 of the support block unit 21.
Place a test bar of the same shape as above, operate the knob 65 to rotate the block drive screw 63, and move the movable block 58 to level the test bar and adjust the height between the center of the test bar and the center of the probe 27. Adjust so that they are the same. This adjustment is performed while checking the value of the linear encoder 29. At this time, also operate the knob 56 to remove the sliding base drive screw 54.
is rotated and the slide table 52 is moved to adjust the thread groove of the object to be measured 22 to be located within the movable range of the measuring element 27.

Next, the object to be measured 22 is placed in place of the test bar, and clamped with the clamp screw 71 if necessary. In this state, turn on each power switch (not shown).
Turn on the sensor to enable measurement, turn on the manual switch (not shown), release the clutch 5, move the detection unit 3 by hand, bring the detection unit 3 into contact with the left stopper 73, and move the detection unit 3. 15 display counter is set to zero.
Next, the detection unit 3 is manually moved to align the measurement tip 28 of the probe 27 with the reference groove position of the object to be measured 22, and the small geared motor 39 is moved.
Turn on the drive switch. As a result, the nut member 34 is connected via the gear train 38 and the feed screw shaft 36.
is driven to the left in FIG. 5, and along with this drive, the measuring stylus 27 advances to the left, that is, toward the side of the object to be measured 22 due to the action of the compression coil spring 31. As a result of this advancement, when the measuring tip 28 at the tip of the gauge head 27 enters the thread groove of the object to be measured 22 and comes into contact with it, the advance of the gauge head 27 is stopped, while the nut member 3
Since the pin 4 moves as it is, the pin 3 fixed to the end face of the notch groove 35 of the nut member 34 and the measuring tip 27
2 is removed, and the first limit switch 41
is activated, the motor 39 is stopped, and thereby the nut member 34 is also stopped. At this time, if the support block unit 21 is not adjusted properly and the probe 27 advances beyond the proper measurement range, the operating pin 43 of the nut member
limit switch 45 is operated, and motor 39
will be stopped. Furthermore, the measured value of the linear encoder 29 at this time and the amount of movement of the detection unit 3 detected by the amount of movement detection means 15 consisting of the laser oscillator 12 etc. are determined by a control computer (not shown).
recorded by.

Next, set the groove pitch and number of measurement points to be measured on the control computer (not shown), turn on the auto switch, and press the start switch.
Measurement begins. That is, in this measurement, first, the small geared motor 39 of the detection unit 3 is driven in the opposite direction to that described above, and as a result, the nut member 34 is also driven in the opposite direction, and the measuring element 27 is moved by the compression coil spring via the pin 32. 31, and the measuring chip 28 escapes from the thread groove of the object to be measured 22. When this evacuation is completed, the second limit switch 44 is actuated by the actuating pin 42 provided on the nut member 35, and the operation of the small geared motor 39 is stopped. Then,
The motor 4 and clutch 5 as a unit drive mechanism are turned on, and the detection unit 3 is connected via the wire 9.
is moved in a predetermined direction, for example, to the right. During this movement, when the rotary encoder 7 detects that the detection unit 3 has moved by the set groove pitch, the motor 4 and clutch 5 are turned OFF, the detection unit 3 is stopped, and the detection unit 3 is free at that position. It is said that it can be moved to. When the detection unit 3 is stopped, the small geared motor 39 of the detection unit 3 is again driven in the advancing direction of the probe 27, and the measurement tip 28 of the probe 27 is moved toward the object to be measured.
When the contact point 27 enters and comes into contact with the groove 2, the geared motor 39 is stopped by the action of the first limit switch 41 in the same manner as described above, and the amount of advance of the contact point 27 at this time is detected by the linear encoder 29.
recorded on the computer. In addition, the stop signal of the geared motor 39 causes the laser oscillator 12 to
Measurement is performed by the movement amount detection means 15 consisting of the following, and the movement amount of the detection unit 3 from the reference point is recorded. At this time, the stop position of the detection unit 3 due to the stop of the motor 4 does not necessarily have to exactly match the set groove pitch. This is clutch 5
Since the detection unit 3 is in a state where it can move freely due to OFF, the measurement chip 28 is in a state where it
When entering groove 2 and stopping, detection unit 3
This is because the detection unit 3 moves as the measurement chip 28 enters, allowing accurate positioning of the detection unit 3.

When the measurement of the first measurement point is completed in this way, the measurement tip 28 escapes from the groove of the object to be measured 22 in the same manner as described above, the detection unit 3 is then moved by the set groove pitch, and the measurement stylus 27 is moved. The measuring chip 28 advances into the groove of the object to be measured 22, and the detection unit 3 is positioned. Next, the linear encoder 29 and the movement amount detection means 1
5, the second measurement is performed, and the same operation is repeated automatically for the set number of measurement points. When the measurement is completed, a buzzer notifies you that the measurement is complete, and the measurement results are displayed on an X-Y plotter, etc. It will be launched by. Note that the value measured by the linear encoder 29 represents the groove depth as a radial deflection of the object 22 to be measured, and the value measured by the movement amount detection means represents the value of the set groove pitch of the object 22 to be measured. . At this time, the setting groove pitch is 1
It is not limited to just one pitch, but can also be two or more pitches.

When the measurement of one object to be measured 22 is completed in this way, the object to be measured 22 is replaced and the measurement is continued in the same manner as described above.

According to this embodiment as described above, after the detection unit 3 is moved by a predetermined amount by the motor 4, the clutch 5 is released to put the detection unit 3 in a free movement state, and in this state, the probe drive mechanism 40 moves the probe. 27 to enter the measuring chip 28 into the groove of the object to be measured 22 to set the position of the detection unit 3,
At this time, the amount of movement of the detection unit 3 is measured by the amount of movement detecting means 15, and the amount of movement of the measuring stylus 27 is measured by the linear encoder 29 as a mechanism for measuring the amount of forward/backward movement. The groove depth as a radial runout can be measured with high precision, and
Can be measured automatically. In particular, the probe 2
7 is separated from the workpiece 22 when it is sent in the axial direction of the workpiece 22 and is not in contact with the workpiece 22, but comes into contact with the workpiece 22 only when measuring the groove pitch and groove depth. Measurement errors due to abrasion of the probe 27 do not occur, and the movement of the detection unit 3 makes it possible to speed up the feeding of the probe 27, so that measurement work can be accomplished quickly. In addition, the movement amount detection means 1
5 uses the laser oscillator 12, so that not only the measured value is accurate, but also no force is applied to the detection unit 3, which is advantageous in that the detection unit 3 can be moved smoothly. Furthermore, the support block unit 21 of the object to be measured 22
Since the device is equipped with a fixed block 57 and a movable block 58, by moving the movable block 58 appropriately, the center of the object 22 can always be aligned with the center of the probe 27, regardless of the diameter of the object 22. This allows for improved measurement accuracy. The support block unit 21 also includes a sliding base 52 that supports the fixed and movable blocks 57 and 58.
Since it is made slidable with respect to the block base 51, the object to be measured 22 can be moved toward the probe 27 without changing the supporting height of the object to be measured. can be easily set within the appropriate measurement range of the probe 27. Furthermore, since the movable block 58 is rotatably (oscillatably) provided on the support shaft 62, it can be reliably adapted to the shape of the object 22 even if there is an installation error of the support block unit 21. I can support it.

In addition, in implementation, the object to be measured 22 is as follows:
The shaft is not limited to a ball screw shaft, but may be a general screw shaft, or a long member having grooves or recesses at a predetermined pitch on the circumferential surface. Further, if the shape of the object 22 to be measured is constant, the support block unit 21 may be a simple fixed V block or the like. Furthermore, the mechanism for measuring the amount of forward and backward movement of the tracing stylus is not limited to the linear encoder 29, but other means may be used.
Furthermore, if it is not necessary to measure the deflection of the object 22 in the radial direction, the linear encoder 29 may be omitted. Furthermore, the unit drive mechanism, probe drive mechanism 40, etc. are not limited to the configurations of the embodiments described above, but may have other configurations.

As described above, the present invention has the effect of providing a measuring device that can automatically measure the groove pitch of a screw.

Furthermore, according to the present invention, the probe is not brought into contact with the object to be measured except when measuring the groove pitch of a screw, etc.
It is possible to eliminate the occurrence of measurement errors due to probe wear, and to speed up measurement work.

[Brief explanation of the drawing]

The figures show one embodiment of the measuring device according to the present invention. Fig. 1 is a plan view showing the overall configuration, Fig. 2 is a front view of Fig. 1, and Fig. 3 is a cross-section of a part of the detection unit. FIG. 4 is a partially sectional front view of FIG. 3, FIG. 5 is a side view of the main part of FIG. 4, and FIG. 6 is a view taken along the - line in FIG. FIG. 7 is a side view with most of FIG. 6 in section. DESCRIPTION OF SYMBOLS 1... Table as a device main body, 3... Detection unit, 4... Motor as a unit drive mechanism, 5... Clutch, 12... Laser oscillator, 1
3...Interferometer, 14...Reflector, 15...Movement amount detection means, 21...Support block unit, 22
...Object to be measured, 27...Measurement head, 29...Linear encoder as a forward/backward movement measuring mechanism, 40...
...Measuring head drive mechanism, 51...Block base, 5
2...Sliding base, 54...Sliding base drive screw, 57...
...Fixed block, 58...Movable block, 59,
60...Beveled surface, 63...Block drive screw.

Claims (1)

[Claims for Utility Model Registration] (1) A unit drive mechanism that moves the detection unit by a predetermined distance along a guide rail; a clutch for freeing movement along the guide rail; a spring for biasing the probe, which is slidably supported by the detection unit in a direction perpendicular to the guide rail, toward the object to be measured; It is movable in the sliding direction and releasably engages with the gauge head, and when it moves forward toward the object to be measured, the gauge head comes into contact with the object to be measured and disengages from the gauge head, and when it retreats, it releases the engagement with the gauge head. a probe drive mechanism having a probe reciprocating member that re-engages with the probe and separates the probe from the object to be measured; a reflector provided on the detection unit; and one end side of the guide rail of the measuring instrument main body. A movement amount detection means configured to include a laser oscillator provided in the detection unit, and an interferometer that measures the movement amount of the detection unit along the guide rail by receiving light from the laser oscillator and the reflecting mirror; Motor of the Mechanism The motor of the probe drive mechanism, the limit switch for restricting advancement and retraction, the limit switch for detecting the engagement between the probe advance/retraction member and the probe, etc., and the unit mechanism according to a predetermined procedure based on the signals of these limit switches and external signals. and a circuit board for operating a probe head drive mechanism, and after the unit drive mechanism moves the detection unit a predetermined pitch relative to the object to be measured, the probe drive mechanism is operated to move the probe to the object to be measured. When the probe is brought into contact with the groove of the object, and when the probe fits into the groove, a detection reading command is output to the movement amount detecting means, and after this detection, the probe drive mechanism is angularly operated to move the probe to the object to be measured. A measuring device comprising: a control device configured to drive and control a series of operations to separate an object from a groove; (2) Utility Model Registration The measuring device according to claim 1, characterized in that the amount of movement of the probe toward the object to be measured is measured by a movement amount measuring mechanism. (3) Utility model registration Claims In either claim 1 or 2, the object to be measured is supported by a plurality of support block units arranged in the longitudinal direction of the guide rail, and the support block units consists of a block base, a slide base that is slidably provided on the block base in a direction orthogonal to the guide rail, and that slides when the slide base drive screw is rotated; The device is equipped with a fixed block and a movable block that is movably provided on the sliding table in a direction orthogonal to the guide rail and that is moved by rotation of a block drive screw. A measuring device characterized in that the surfaces on which the measuring device is placed and facing each other form a V-shape and are beveled surfaces for adjusting the height position of the object to be measured by moving the movable block.