JP3071638B2 - Outer diameter measuring device for thin workpieces - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for measuring the outside diameter of a thin workpiece, and more particularly to a centerless grinder for through feed grinding, for example, for measuring the outside diameter of a thin cylindrical workpiece. The present invention relates to an outer diameter measurement technique suitable for continuously measuring with a laser beam during movement after grinding.

[0002]

2. Description of the Related Art Conventionally, a workpiece (hereinafter, referred to as a workpiece) in, for example, through feed grinding of a centerless grinding machine.
In the measurement of the outer diameter of the workpiece W, as shown in FIG. 5, dry air is blown against the outer diameter of the workpiece W being transported after grinding by an air blow device a provided in the transport path.
After removing the grinding fluid, dust, grinding debris, and the like adhering to the air blow device a, the work W is passed through a laser measuring device b provided on the downstream side in the transport direction of the air blow devices a, a to measure the outer diameter. Is going.

[0003] The laser light in the laser measuring device b is
The workpiece W moving in the axial direction is scanned in the vertical direction so as to be orthogonal to the axis. Then, as a result of the measurement of the outer diameter of the work W by the laser measuring device b, when it is necessary to correct the cutting amount of the grinding machine c, a correction signal is sent from the control device f to the correction device g of the grinding machine c. The cut amount is corrected.

[0004]

However, the above-mentioned measuring apparatus has the following problems.

(1) When the workpiece W to be measured is a so-called thin workpiece whose axial width is smaller than its outer diameter, such as an inner or outer ring of a bearing or a valve seat, the workpiece discharged from the grinding machine c. In the case of W, the transfer posture on the transfer device e is unstable, and the measurement accuracy is poor.

(2) When placing the work W on the transfer device e, it is necessary to narrow the interval between the works W so that the work W does not fall down. The accumulation of the work W from the board c to the laser measuring device b) is inevitably increased, and even if an attempt is made to correct the processing dimension of the workpiece W, the correction timing is delayed, and the variation in the processing dimension increases.

(3) In the case where the work W has a ring shape, the coolant liquid has entered the inner diameter of the work W, and even if the measurement surface (work outer diameter) is cleaned (air blown), the inside of the work W is gradually removed. The coolant liquid leaks out, deteriorating the cleaning effect and causing variations in measurement accuracy.

(4) When the workpiece W is subjected to through-feed grinding with a centerless grinding machine, it is necessary to perform a grinding operation by placing a dummy at the head so that the workpiece W does not fall in the grinding wheel at the start of the grinding. A mechanism for processing this dummy after completion of the measurement is required.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional problems, and an object of the present invention is to reduce the outer diameter of a work, for example, by grinding a thin work and then transporting the work. An object of the present invention is to provide an outer diameter measuring device for a thin workpiece which can be measured quickly and accurately by a laser beam.

[0010]

In order to achieve the above object, an outer diameter measuring device according to the present invention is provided on a carry-out side of a machine tool, and conveys a worked workpiece in a radial direction thereof; For the work transferred by this transfer device,
A laser measuring device that scans the laser beam in the radial direction to measure the outer diameter of the work.

Further, the centerless grinding machine according to the present invention is characterized in that the above-mentioned outer diameter measuring device is connected and arranged on the work unloading side.

[0012]

In a machine tool equipped with the outer diameter measuring device of the present invention, for example, a centerless grinder for through feed grinding, a thin work that has been ground is discharged from the grinder by a thrust at the time of grinding. The grinding dummy placed at the head of the work at the start is collected and held by the dummy collecting section provided on the unloading side of the grinding machine by this thrust.

Therefore, the work continuously discharged from the grinding machine following the dummy is naturally dropped by its own weight from between the end face (the base end face) of the dummy collected and held by the dummy collection section and is lowered. Is discharged onto a discharge chute which constitutes a posture conversion unit of the outer diameter measuring device provided in the apparatus.

At this time, the posture of the work is changed from a standing state at the time of grinding to a lying state, and the work is conveyed in this lying state. That is, the workpiece is converted from the axial movement in the grinding processing to the radial movement.

The work sent to the transfer section of the transfer device is moved by an air blow device provided in the middle of the transfer.
Dry air is blown on its outer diameter and end face,
After the grinding fluid, dirt, grinding debris, etc. are removed, it is sent into the laser measuring device.

In the laser measuring device, the laser light is scanned in the direction of transport of the work, for example, in the horizontal direction, the laser light is scanned in the radial direction of the work, and the outer diameter of the work is continuously measured during the transport.

[0017]

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

FIGS. 1 to 4 show a centerless grinding machine according to the present invention. More specifically, this grinding machine is capable of through-feed grinding so-called thin workpieces W having a narrow axial width. Then, the workpieces W, W,.
An outer diameter measuring device 2 for continuously measuring the outer diameter of the workpiece W while transporting the workpieces W, W,.
It has.

Reference numeral 3 denotes a bed, 4 denotes a grinding wheel, 5 denotes an adjustment wheel, 6 denotes a blade, and 7 denotes guide plates on the work loading side and the work unloading side. The grinding machine is also provided with a correcting device 8 for correcting the processing dimension and a control device 9 for controlling the driving of the correcting device 8 according to the measurement result of the outer diameter measuring device 2.

The outer diameter measuring device 2 includes a workpiece W,
, And a laser measuring device 11 for measuring the outer diameter of the workpieces W, W,...

The transfer device 10 includes an attitude conversion unit 15 and a transfer unit 16. The posture changing unit 15 changes the posture of the work W from the standing state to the lying state. Specifically, the posture changing unit 15 includes a discharge chute 20 disposed below the unloading side of the grinding machine. It is configured to be discharged. In connection with this, discharge chute 2
Above 0, a dummy collection unit 21 is provided.

The dummy collecting section 21 collects and holds the dummy W 'used at the start of grinding. The dummy collecting section 21 is arranged to face the guide plates 7, 7 on the work unloading side. Is set at the same height position as. A stopper 21b is provided at the rear of the dummy collection unit 21 so that the collection position can be adjusted.

Although not shown, the dummy collection unit 2
1 is provided with a means for drawing in the dummy W 'in the direction of the stopper 21b, and has a structure for securing a fall space A for the work W. As the retracting means, a magnet provided at the tip of the stopper 21b, a clutch, an air cylinder, or the like may be employed.

The discharge chute 20 is provided below the falling space A existing between the discharge side end of the blade 6 and the dummy collection section 21 and is arranged so as to be inclined downward toward the downstream side in the transport direction. ing. More specifically,
The discharge chute 20, as shown in FIG. 1, has a substantially cylindrical shape, the upstream end unloading side end of the blade 6 (Se
It enters under the work-out side end of the interless grinding machine , and its downstream end is provided facing the upstream end of the transport section 16. The width of the falling space A in the transport direction is set so that the works W can be dropped one by one.

The transport section 16 transports the workpiece W, the attitude of which has been changed by the attitude converting section 15, as it is.
More specifically, it is in the form of a belt conveyor, and comprises a first belt conveyor 16a and a second belt conveyor 16b, which are linked by a link chute 16c.

First and second belt conveyors 16
a, 16b are a plurality of belt wheels 22, 22,.
, And the conveyor belts 2
3, 24 are hung respectively. Are connected to a belt drive source (not shown) for each of the first and second belt conveyors 16a and 16b, and the rotation of the belt drive source is performed. Is transmitted to the belt wheel 22, and the transport belts 23 and 24 are rotationally driven.

The conveyor belt 23,
The transfer speed of the transfer device 24 (the transfer device 10) is set to be constant and set to be slightly faster than the work discharge speed of the centerless grinding machine.

The first belt conveyor 16a
As shown in FIG. 3 (a), the transport belt 23 is in the form of a round belt.
3a and 23a. This belt 23a,
23a is set so that the interval is slightly narrower than the work W so that the work W can be held.

On the other hand, the conveyor belt 24 in the second belt conveyor 16b is made of a thin plate-like elastic steel belt, and the lower surface of the conveyor belt 24 is located at the measurement position where the laser measuring device 11 is arranged. A belt guide 25 for sliding and guiding is provided, and the upper surface of the transport belt 24 guided by the belt guide 25 is configured to be a measurement reference surface 24a by the laser measuring device 11 (FIG. 3 (b)). )).

The second belt conveyor 16b includes:
As shown in FIG. 3B, side guides 26 are provided at portions other than the measurement position where the laser measuring device 11 is disposed so as to guide and hold the work W from the side.

The transport device 10 constructed as described above
After the work W is changed in posture from the standing state to the lying state by the posture changing unit 15, the work W is conveyed in the radial direction by the belt conveyor of the conveying unit 16.

Then, a portion of the transfer section 16 during the transfer,
Specifically, the laser measuring device 11 is arranged at a downstream end of the second belt conveyor 16b. The laser measuring device 11 measures the outer diameter of the work W conveyed by the conveying device 10 by scanning the work W with laser light L in the radial direction.

The laser measuring device 11 includes a light projecting unit 27 for emitting a laser beam L, a light receiving unit 28 for receiving the laser beam L, and a control unit 29 for calculating and processing the measurement result by the light receiving unit 28.
These are the second belt conveyor 16 not shown
b.

The laser beam L from the light projecting section 27 is
Is scanned in the radial direction of the work W, that is, in the feed direction, from the direction perpendicular to the feed direction of the workpiece W to measure the outer diameter of the work W being conveyed. Note that the arrow L in FIG. 2 indicates the scanning direction of the laser measuring device 11.

The scanning position of the laser beam L is
The height of the portion from the measurement reference plane 24a is calculated and set in advance depending on which part of the outer diameter is to be measured. This makes it possible to measure even the workpiece W having an uneven outer diameter such as a bearing track dimension as shown in FIGS. 4A to 4D with reference to the end face. That is, it is possible to measure the outer diameter D of the work W shown in each of FIGS.

In the outer diameter measuring device 2 of the present invention, air blow devices 30, 30,... For cleaning the work W are arranged at appropriate positions upstream of the laser measuring device 11. Specifically, as shown in FIG. 1, it is provided above the falling space A, on the first belt conveyor 16a, and on the second belt conveyor 16b.

Then, dry air is blown to the outer diameter and the end face of the work W by these air blow devices 30, 30,... To remove grinding fluid, dust, grinding debris and the like adhering to the surface.

Next, the operation of the centerless grinding machine according to the present invention will be described.

First, the workpiece W sent between the grinding wheel 4 and the adjusting wheel 5 of the centerless grinding machine by the feeding device 1
Is sent to the guide plates 7, 7 on the work carry-out side by the thrust at the time of grinding. At this time, the dummy W 'disposed at the head of the workpiece W at the start of grinding has the dummy upper surface 21a of the recovery unit 21 and the blade 6 set at the same height. It is collected and held in the unit 21.

The workpieces W, W,... Discharged from the centerless grinding machine following the dummy W 'are dropped in the fall space A between the dummy W' end face (base end face) of the collecting section 21. Then, the water drops naturally by its own weight and is discharged onto a discharge chute 20 provided below. At this time, since the width of the falling space A in the transport direction is set so that the workpieces W can be dropped one by one, the workpieces W, W, W,. Are separated from each other and are surely dropped onto the discharge chute 20 one by one.

The workpiece W dropped on the discharge chute 20
The postures of W,... Are changed from the standing state to the lying state by the posture converting unit 15, and the transfer device 10 is kept in the lying state.
And is conveyed after being converted from axial movement to radial movement.

On the other hand, the transfer speed of the transfer device 10 (work W
Is higher than the threading speed of the grinding, so that when the work W moves on the conveyor belt 23, the work W is sent at a higher speed, and is separated from the subsequent work W to be separated from the conveyor belt 23. Will be moving. The transport speed in this case is set such that the transport pitch of the workpieces W, W,... (The gap between the workpieces W, W) is wider than the scanning width of the laser beam L of the laser measuring device 11.

The work W sent into the transfer device 10 is ground by dry air blown to its outer diameter and end surface by air blow devices 30, 30,... The liquid and the like are removed, and preparation for measuring the outer diameter of the work W is performed.

When the workpiece W ready for measurement by the air blow device 30 passes through the measurement position of the laser measuring device 11, the laser beam L scanned in the transport direction of the workpiece W, that is, in the radial direction of the workpiece W, By this, the outer diameter dimension is continuously measured during conveyance.

If the measurement result of the outer diameter dimension of the work W is within the allowable range of the set processing dimension, the work W is discharged as it is as a non-defective product to the work collection section 31, and the above measurement result is returned to the allowable range. In the case of entering the correction range within the range, in addition to the collecting operation, a correction signal is output from the control device 9 and the correction device 8 corrects the processing dimension.

On the other hand, when the above measurement result is out of the correction range, N
In the case of G (dimension failure), an NG discharge device (not shown) is activated by a signal from the control device 9, and the work W is discharged to the NG discharge portion.

The above-described embodiments are merely intended to show preferred embodiments of the present invention, and the present invention is not limited to these embodiments, and various design changes can be made within the scope thereof.

For example, in the above embodiment, the transport unit 16 is
And the second two belt conveyors 16a and 16b.
If 4a can be secured, these may be combined into one, and the belt used for the belt conveyor may be changed to a flat belt, a round belt, or the like.

Although the second belt conveyor 16b is provided horizontally in the above embodiment, it is sufficient that the laser beam L of the laser measuring device 11 is scanned in the transport direction of the work W, that is, in the radial direction. It is also possible to provide the second belt conveyor 16b with an inclination.

Further, the outer diameter measuring apparatus of the present invention is applicable to machine tools other than the centerless grinding machine.
In addition to the outer diameter of the work W as in the illustrated embodiment, the length of the bar-shaped work can be measured by using a similar conveyance method.

[0051]

As described in detail above, according to the present invention,
Various effects described below can be obtained. (1) The thin workpiece is conveyed in the radial direction, and the laser beam scans in the conveying direction to measure the outer diameter of the workpiece. High measurement results can be obtained.

That is, since the workpiece is transported in a state in which the posture has been changed from the standing state to the lying state, even a thin workpiece can be transported in a more stable state than before, and the outer diameter of the workpiece is measured by a laser measuring device. During measurement, the workpiece can be measured with the workpiece in the lying state, so it is possible to measure the outer diameter based on the end face of the workpiece, and the outer diameter such as the track dimensions of bearings, which has been considered impossible or difficult so far. The dimensions can also be measured.

(2) Conventionally, in the case of a thin work, since the work is transported in a state of being closely contacted in the axial direction, the number of works existing between the grinding work point and the laser measuring device is very large. However, according to the present invention, since the workpiece is laid down and transported in the radial direction as it is, the transport attitude can be stabilized and the workpiece feeding speed can be increased.

Therefore, the number of workpieces existing between the grinding operation point and the laser measuring device is far smaller than in the conventional case, timely dimensional correction is possible, and variation in processing dimensions is small.

(3) In addition, since the work is conveyed in the radial direction, even in the case of a cylindrical work, the coolant or the like that has entered the inner diameter of the work can easily come out, and the cleaning effect of the air blow device is maintained at a high level. it can.

(4) Further, since the centerless grinding machine of the present invention is provided with the dummy collecting section for collecting and holding the dummy used at the start of grinding, the dummy can be automatically collected in the dummy collecting section, and the processing of the dummy can be performed. It can be done easily.

(5) In addition, since the outer diameter of the work being conveyed can be accurately and continuously measured with a laser measuring device, all of the ground work can be measured. In addition, the dimensions of a small-width, small-diameter work such as a miniature bearing can be measured. It is suitable for management, and also suitable for automation of the device.

(6) Since the work is conveyed and measured on the basis of the center, the model number of the work can be changed only by adjusting the position of the belt guide without changing the width of the conveyor belt or the like, and the setup can be changed. Easy.

[Brief description of the drawings]

FIG. 1 is a side view showing an example of a centerless grinding machine provided with an outer diameter measuring device for a thin workpiece according to the present invention.

FIG. 2 is a plan view showing an example of the centerless grinding machine.

FIG. 3 is a view showing a conveyor belt of the centerless grinding machine, and FIG. 3 (a) is a sectional view taken along line XX of FIG.
FIG. 2B is a sectional view taken along the line YY of FIG.

FIG. 4 is an explanatory diagram showing an example of the shape of a work that can be measured by the outer diameter measuring device of the present invention.

FIG. 5 is a side view showing a configuration of a conventional outer diameter measuring device.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 feeding device 2 outer diameter measuring device 3 bed 4 grinding wheel 5 adjusting wheel 6 blade 7 guide plate 8 correction device 9 control device 10 transport device 11 laser measuring device 15 attitude conversion unit 16 transport unit 20 discharge chute 21 dummy recovery unit 23, 24 Conveying belt 24a Measurement reference surface 25 Belt guide 26 Side guide 30 Air blow device 31 Work collection part W Thin work W 'Dummy A Falling space L Laser light

Continuation of the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) B23Q 17/20 B24B 49/12 G01B 11/08

Claims (2)

(57) [Claims] (1) A thin-width workpiece is ground by through feed grinding.
In a centerless grinding machine that performs cylindrical surface grinding,
Measuring the outside diameter of thin workpieces machined by turres grinding machines
An outer diameter measuring device, which is provided on the work unloading side of the centerless grinding machine during grinding.
A dummy that collects the used dummy by using the thrust during grinding
The recovery section and the thin workpiece after processing are transported in the radial direction
Transporting device for transporting and the work transported by this transporting device
Scans the workpiece with laser light in the radial direction to determine the outer diameter of the workpiece.
A laser measuring device for measuring, and the dummy collecting unit is configured to carry a workpiece of the centerless grinding machine.
The dummy collection part
In a state where the dummy is collected and held,
The centerless grinding machine between the workpiece discharge side end and the
Forming a falling space for free-falling a thin workpiece, and below the falling space, a thin workpiece falling in the falling space
While changing the posture of the object to the lying state,
A discharge chute for guiding is provided.
Diameter measuring device for thin workpieces. 2. The method according to claim 1 , wherein the dummy collecting section includes a dummy collecting section.
The collection position of the collected dummy is adjustable.
The outer diameter of a thin workpiece according to claim 1, characterized in that:
measuring device.