JPH0752037A - Automatic thickness controlling stone polishing device - Google Patents

Abstract

PURPOSE:To automatically polish a stone up to its finish thickness so as to remarkably improve the workability by only setting the finish thickness of the stone at first. CONSTITUTION:A feed screw shaft 24 is fitted to the main spindle fitting base 6 of a stone polishing device, an elevatable block 29 threadedly engaged with the screw shaft is provided with a sensor fitting base 30, a limited reflection type distance sensor 32 is fitted to the lower end of the base 30 close to the measuring surface 20 of a stone 19, and the upper end of the sensor fitting base 30 is connected to a wire drawing out type linear encoder 33 fitted to the right and left running base 4 of a polishing device. A control device 40 is provided, for detecting the height of the upper face of the stone 20 from the total distance consisting of the vertically moved distance of the distance sensor 32 measured here and a distance between the distance sensor 32 and the stone measuring surface 20, and stops a main spindle 8 when the stone 20 reaches the set thickness. Further a water guard blade 36 is fitted on the side of the distance sensor 32, and an air injection nozzle 35 is fitted inside the blade 36, facing to the measuring surface 20.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stone polishing apparatus for automatically controlling the finished thickness of stone.

[0002]

2. Description of the Related Art Generally, after a stone material such as a rectangular parallelepiped or a cube having a flat surface is ground, the surface of the stone material is polished by an automatic polishing device for finishing. In a conventional automatic polishing apparatus, a rootstock is placed on a surface plate, a ground stone material is placed on the rootstock, and then the vertical and horizontal dimensions and thickness of the top surface of the stone material are measured by a scale. Next, after setting the vertical and horizontal dimensions of the top surface of the stone material and the number of times of polishing while descending intermittently according to the polishing amount on the control panel, turn on the start switch. When the switch is turned on, the spindle that moves three-dimensionally descends, and the polishing machine for rough finishing formed by the diamond grindstone connected to the lower end of the spindle first contacts the top surface of the stone material and moves horizontally while polishing surface. The plane of is automatically read to store the maximum thickness and the minimum thickness, and then the upper surface is ground horizontally according to the minimum thickness. After that, while the spindle is intermittently lowered by a few mm, a polishing disk formed of a diamond grindstone is rotated to planarly move and polish the upper surface of the stone material. For example, a single descending distance of the spindle is 0.
If it is set to 5 mm and it is set to polish 9 times, 4.5
The machine stops when it is ground.

Thereafter, the thickness of the stone material is measured again on the scale, the polishing amount up to the finished dimension is calculated, and the number of times of polishing is calculated from the preset one-time descending distance of the polishing plate, After setting the number on the control panel, turn on the start switch again for automatic polishing. In this way, the polishing platen is lowered by a predetermined height, and the upper surface is polished in the range of several mm to several tens of mm for rough finishing. When the finished thickness is reached, the polishing machine formed of a diamond grindstone attached to the tip of the spindle is automatically replaced with a polishing machine for polishing and polishing is performed. Several polishing machines having different roughness are attached to this polishing machine, and polishing machines having a large roughness are automatically replaced with polishing machines having a small roughness one by one to perform polishing.

However, the roughing polishing machine formed of the diamond grindstone used first consumes a large amount of hard stone material, and has a problem that its thickness changes during use. For this reason, with conventional polishing equipment, it is not possible to automatically polish from roughing to polishing by setting the amount of polishing in advance, and while measuring the thickness of the stone material with a scale, it is possible to automatically polish every few mm. There was a problem that workability was poor because it had to be polished one by one.

[0005]

DISCLOSURE OF THE INVENTION The present invention eliminates the above-mentioned drawbacks, and only by first setting the finishing thickness of a stone material, the automatic polishing is performed to the finishing thickness automatically and the workability is greatly improved. A thickness control stone polishing apparatus is provided.

[0006]

The invention according to claim 1 of the present invention is a combination of front and rear guide rails and left and right guide rails,
An elevating mechanism is provided on the traveling base guided by the left and right guide rails, a spindle mounting base is attached here to support the spindle in a three-dimensionally movable manner, and a polishing plate is attached to the lower end of this spindle.
In a stone polishing machine that polishes the top surface of stones while spraying grinding water, a feed screw shaft is mounted vertically along the spindle on the spindle mount to which the spindle is attached. The block is equipped with a sensor mount, and the non-contact distance sensor is mounted on the lower end of this sensor mount in close proximity to the stone measurement surface, and the upper end of the sensor mount is mounted on the horizontal running platform to measure the travel distance. The height of the top surface of the stone is detected from the total distance between the vertical movement distance of the non-contact distance sensor measured by this movement distance measuring device and the distance between the non-contact distance sensor and the stone measurement surface. By installing a control device that stops the spindle when the stone reaches the set thickness, and further installing a water-repellent blade on the lower side of the sensor mounting base that makes sliding contact with the measurement surface To, and is characterized in that mounted toward the air ejection nozzle to the measuring surface in a non-contact distance sensor side of the one side.

According to a second aspect of the present invention, the moving distance measuring device attached to the traveling platform in the left-right direction is composed of a wire-drawing linear encoder, and the lower end of the wire pulled out from the wire-mounting linear encoder serves as a sensor mounting base. It is characterized by being connected.

Further, the invention according to claim 3 of the present invention is such that the non-contact distance sensor outputs a position holding signal in which the amount of received light of the light reflected on the measurement surface of the stone material reaches a maximum value at a predetermined distance. It is characterized by being formed of a reflection type distance sensor.

[0009]

According to the automatic thickness control stone polishing apparatus of the present invention, when the finish thickness of the stone is set and then the start switch is turned on, the spindle of the polishing apparatus that moves three-dimensionally moves down and the rough polishing machine is used. Rotates while intermittently descending, and the top surface of the stone material is planarly moved and polished. At this time, when the spindle mount is lowered, the non-contact distance sensor integrally connected to the spindle mount is also lowered, and this moving distance is measured by the moving distance measuring device and output to the control device.

The non-contact distance sensor attached to the lower end of the sensor mounting base moves downward while searching the upper surface of the stone when the feed screw shaft rotates and the elevating block screwed here descends, and the non-contact distance sensor When the distance between the distance sensor and the distance sensor reaches the set distance, it stops while keeping the distance constant. On the other hand, the automatic polishing device intermittently descends while the polishing platen rotates to planarly move and polish the top surface of the stone material, and the non-contact distance sensor also intermittently descends at a set distance from the measurement surface. The position hold signal is output while it is held. In this way, while the non-contact distance sensor maintains a certain distance from the top surface of the stone, the top distance of the stone is measured by measuring the moving distance of the non-contact distance sensor with the movement distance measuring device, and the thickness of the stone is measured. When the finished thickness reaches a preset value, a stop signal is output to the control unit of the polishing apparatus, the polishing machine stops, and rough finishing is completed.
After that, the rough finish polishing disc is removed, and the polishing polishing discs having different roughnesses are automatically replaced one after another for polishing polishing.

Grinding water is sprayed from the center of the polishing machine during polishing, and cutting water mixes into muddy water, which scatters in all directions by centrifugal force. However, the lower end beside the non-contact distance sensor is a stone material. Since a water-repellent blade that is in sliding contact with is attached here, it is shielded here, and at the same time air is jetted from the air jet nozzle toward the measurement surface and the grinding water is blown away, so the wet measurement surface is exposed. Therefore, accurate distance measurement can be performed.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to FIGS. FIG. 1 is an automatic thickness control stone polishing apparatus in which front and rear guide rails 1 and 1 are provided at intervals,
Front and rear traveling platforms 2 and 2 are provided on this, and left and right guide rails 3 are provided on the front and rear guide rails 1 and 1 at right angles. The left and right guide rails 3 are provided with a left and right carriage 4, on which an elevating mechanism 5 is attached, and on the elevating mechanism 5, a spindle mount 6 is provided so as to be vertically movable. A spindle 8 connected to a spindle motor 7 is vertically provided on the spindle mount 6, and the spindle 8 is movably supported in three dimensions. In FIG. 2, 9 is a front / rear motor that drives the front-rear traveling platforms 2, 2, 10 is a left-right motor that moves the left-right traveling platform 4, and 11 is an elevating motor provided in the elevating mechanism 5.

Further, as shown in FIG. 1, a polishing plate holder 13 whose side surface is surrounded by a cylindrical cover is rotatably supported below the main shaft 8, and eight polishing plates 14a to 14h are attached thereto. One polishing plate is selectively connected to the tip of the spindle 8. Further, the polishing plate 14a is for rough finishing formed by a diamond grindstone, and the polishing plates 14b to 14h are for polishing for increasing the roughness sequentially from the smaller one. Cylinders 15 and 15 are attached to both sides of the main shaft 8 so that when the rod extends downward, the main shaft 8 connected to the tip of the cylinder descends, and when it is connected to the polishing plate 14b, the cylinders 15 and 15 lower together. It has become. On the floor below the main shaft 8, a surface plate 17 made of stone material is provided, and a stone material 19 processed into a predetermined size is placed on the surface plate 17 via a rootstock 18.

Reference numeral 22 is a thickness measuring instrument, which is vertically mounted on the side of the spindle mount 6 so as to move up and down integrally.
As shown in FIGS. 4 and 5, the thickness measuring instrument 22 has a feed screw shaft 24 vertically supported by a U-shaped support frame 23, and a timing pulley 25a is attached to an upper end of the feed screw shaft 24. . A pulse motor 26 is attached to the upper portion of the support frame 23, and a timing pulley 25b is connected to the tip of the pulse motor 26. The timing pulley 25a and the timing pulley 25a are connected by a timing belt 27.

The feed screw shaft 24 has a lifting block.
29 are screwed together so that the feed screw shaft 24 rotates to move up and down. Further, a sensor mount 30 is connected to the side of the elevating block 29, and a limited reflection type distance sensor 32 is attached to the lower end of the sensor mount 30. As shown in FIG. 5, the limited reflection type distance sensor 32 has a light emitting portion and a light receiving portion attached at an angle, and infrared rays emitted from the light emitting portion are reflected by the measuring surface 20 as shown by phantom lines. Detects the amount of light received when it reaches the light receiving section. When the position where the amount of received light is maximum, that is, the set distance is reached, the position hold signal
It outputs to 26 and stops rotation.

As shown in FIG. 3, the left and right guide rails 3
A wire pull-out type linear encoder 33 is attached to the left and right traveling bases 4 that travel along the, and the lower end of the wire 34 pulled out from this is connected to the upper end of the sensor mounting base 30. Further, as shown in FIG. 5, an air jet nozzle 35 is provided beside the limited reflection type distance sensor 32 with its tip facing the measurement surface 20, and a water shield made of a rubber plate is provided on the side of the main shaft side. The measuring surface of the stone 19 as shown by the blade 36 in phantom
It is mounted so that it can slide on 20.

The control circuit is constructed as shown in FIG. 6, and the control device 40 is provided with a control panel (not shown) for setting the finished thickness of the stone 19 and the height of the stock 18, and this control panel An indicator is provided to display the thickness of the stone material 19 being polished. The limited reflection type distance sensor 32 is connected to a control device 40, and the control device 40 is further connected to a motor control unit 41 that drives the pulse motor 26. The limited reflection type distance sensor 32 detects the amount of light received at the light receiving unit, and when the amount of received light is small, a signal is not output, and the limited reflection type distance sensor 32 searches the stone material 19 by rotating the pulse motor 26. A position holding signal is output to the control device 40 at a position where the amount of received light that has descended and reflected is maximum, and a stop signal is output from this to the motor control unit 41 to stop the rotation of the pulse motor 26 and the limited reflection type The height of the distance sensor 32, that is, the distance from the measurement surface 20 is kept constant. The air injection nozzle 35 is connected to the air compressor 43 via an air valve 42, and the air valve 42 is opened by a signal from the control device 40 to inject air from the air injection nozzle 35 onto the measurement surface 20. ..

Wire-drawing linear encoder 33
Is connected to the control device 40 via the counter 44, where the distance between the encoder 33 and the limited reflection type distance sensor 32 is obtained from the wire pullout amount of the wire pullout type linear encoder 33, and this and the position holding signal are output. The total distance between the limited reflection type distance sensor 32 and the measurement surface 20 in the state where it is present, and outputs a drive signal to the polishing apparatus control unit 45 until the preset total distance, that is, the finished thickness of the stone 19 is reached. Then, the polishing tool 14a is intermittently lowered little by little and moved in plane to cut the stone material 19.

Next, the operation of automatically polishing to a predetermined thickness by the stone polishing apparatus having the above structure will be described. First, as shown in FIG. 1, a base 18 is laid on a surface plate 17, and a stone material 19 cut into a predetermined shape is placed thereon. Next stone 19
The vertical and horizontal dimensions of the upper surface of the polishing table are measured on a scale and set on the control panel of the polishing apparatus to set the plane movement range of the polishing panel 14a.
Further, as shown in FIG. 7, the control device 40 has a distance L0 between the surface plate 17 and the wire drawing linear encoder 33 in advance,
The length Lb of the sensor mount 30 and the set distance ΔX between the limited reflection type distance sensor 32 and the measurement surface 20 of the stone 19 are input. The limited reflection type distance sensor 32 has a set distance ΔX set to, for example, 10 mm.

Thereafter, after setting the dimension D of the stock 18 and the finished thickness X0 of the stone 19 on the control panel of the control device 40, the start switch is turned on. When the switch is turned on, as shown in FIG. 3, the spindle that moves three-dimensionally descends, and the polishing machine 14a for rough finishing formed of a diamond grindstone is elastically supported by the cylinder 15, and the stone 19 The horizontal surface of the polishing surface is automatically read while contacting the upper surface of the, and the maximum thickness and the minimum thickness are stored, and the upper surface is ground horizontally according to the minimum thickness. After that, the spindle 8 is intermittently lowered by a few millimeters, and the polishing machine 14a is formed of a diamond grindstone.
Rotates to move the top surface of the stone material 19 in a plane and polish it.
At this time, when the spindle mount 6 supporting the spindle 8 descends,
The thickness measuring instrument 22 integrally connected to this also descends. At this time, since the wire pull-out type linear encoder 33 is fixed to the left and right traveling bases 4 and the sensor mounting base 30 descends, the wire 34 connected to the upper end is pulled out from the encoder 33, and the pulling amount is shown in FIG. Measured by the counter 44, this data is output to the control device 40.

On the other hand, in the limited reflection type distance sensor 32 attached to the lower end of the sensor mount 30, the light emitting portion and the light receiving portion are attached at an angle as shown in FIG. 5, and infrared rays are emitted from the light emitting portion. However, if the distance from the stone material 19 is long, the amount of light reflected and reaching the light receiving portion is small, so that no signal is output and the pulse motor 26 continues to rotate. Therefore, the feed screw shaft 24 connected to the motor 26 rotates, the lifting block 29 screwed here descends, and the limited reflection type distance sensor 32 mounted on the sensor mount 30 searches for the upper surface of the stone material 19. Going down.

As the stone 19 is approached, infrared rays are reflected on the measurement surface 20 and the amount of received light gradually increases.
The maximum amount of light received reaches 10 mm. At this time, the control device 40
A position holding signal is output to the motor controller 41, and a stop signal is output from the motor controller 41 to stop the rotation of the pulse motor 26. Therefore, the height of the limited reflection type distance sensor 32,
That is, the distance from the measurement surface 20 is kept constant. Separately from this, with the cylinder 15 locked, the automatic polishing machine descends intermittently by a few millimeters of commas while polishing machine 14a.
Rotates to move the top surface of the stone material 19 in a plane and polish it.
As described above, the polishing platen 14a descends intermittently, but the limited reflection type distance sensor 32 of the thickness measuring instrument 22 connected to the spindle mount 6 also descends intermittently at the same time.
The position holding signal is output while the distance ΔX between and is held at the set value of 10 mm, for example.

As a result, as shown in FIG. 7, since the distance L0 between the surface plate 17 and the encoder 33 is constant, the distance between the encoder 33 and the sensor mount 30, that is, the wire 34.
Let La be the drawing length of and the thickness of the stone 19 be X,
L0 = La + Lb + .DELTA.X + X + D. Where L
Since 0, Lb, ΔX, and D are constant, X = (L0-L
b−ΔX−D) −La, and the thickness X of the stone 19 decreases in proportion to the increase in the drawing length La of the wire 34. Therefore, this relationship is calculated by the control device 40 of FIG. 6, and when the thickness X of the stone material 19 reaches the preset finish thickness X0, a signal is output to the polishing device control portion 45, and the polishing device attached to the tip of the spindle 8 is polished. The rotation of the board 14a stops and the rough finishing is completed. After that, the polishing disc 14a is removed, the operation of the thickness measuring instrument 22 is released, and the cylinder 15 elastically returns to the polishing discs 14b to 14h for polishing, which have different roughness on the main shaft 8 in order. It is automatically replaced and polished for polishing.

During polishing, as shown in FIG.
Grinding water 46 is sprayed from the center of a onto the cutting surface, and cutting powder is mixed to form muddy water, which scatters in all directions by centrifugal force and flows to the measuring surface 20 below the limited reflection type distance sensor 32. Since the water shield blade 36 whose lower end is in sliding contact is attached to the side of the distance sensor 32, it is shielded here and flows slightly to the measurement surface 20 side. At the same time, since air is jetted from the air jet nozzle 35 toward the measurement surface 20 and the grinding water 46 is blown away, the wet measurement surface 20 is exposed, and infrared rays are radiated and reflected on this portion, so that an accurate distance is obtained. The measurement can be performed. Depending on the type of stone material 19, there are white stones and black stones, or stones in which white and black are mixed, but the reflectance may differ in the dry state, which may cause an error in distance measurement. Since the measurement surface 20 is measured in a wet state, the difference in reflectance is slight and there is almost no error in distance measurement, and the thickness of any type of stone material 19 can be accurately controlled.

Therefore, in the present invention, the distance between the encoder 33 mounted on the left and right traveling platform 4 which is the height reference and the upper surface of the stone material 19 is limited by the combination of the encoder 33 and the limited reflection type distance sensor 32. The distance sensor 32 follows the movement of the spindle mount 6, and the limited reflection type distance sensor 32 measures in a non-contact state while maintaining a constant distance from the measuring surface 20 of the stone material 19, so that there is no wear. In addition, the measurement can be performed regardless of the amount of abrasion of the grindstone of the polishing board 14a, and the measurement surface 20 prevents the infiltration of muddy grinding water 46 by the air blown from the water-repellent blade 36 and the air jet nozzle 35, and constantly Since the measurement is performed with the wet measurement surface 20 exposed, accurate measurement can be performed.

In the above embodiment, the wire pull-out type linear encoder 33 is used as the moving distance measuring device, but other configurations such as a magnetic type linear scale and a pulse type moire fringe applied position reading scale may be used. good. As the non-contact distance sensor, the case where a limited reflection type distance sensor that outputs a position holding signal in which the amount of light reflected by the measurement surface of the stone reaches a maximum value at a predetermined distance is shown. It may be configured to measure with light.

[0027]

As described above, according to the automatic thickness control stone polishing apparatus according to the present invention, the moving distance measuring device and the non-contact distance sensor are combined so that the non-contact distance sensor follows the movement of the spindle. The contact distance sensor measures in a non-contact state while maintaining a certain distance from the top surface of the stone, so it can be measured regardless of the amount of abrasion of the polishing machine, and the measurement surface is muddy water by spraying air with a water-repellent blade. Prevents intrusion of grinding water and always measures with the wet measurement surface exposed so that accurate measurements can be made and the stone material can be automatically ground to the set thickness, greatly improving workability. Can be improved.

[Brief description of drawings]

FIG. 1 is a front view showing an automatic thickness control stone polishing apparatus according to an embodiment of the present invention.

FIG. 2 is a side view of the automatic thickness control stone material polishing apparatus shown in FIG.

FIG. 3 is a front view showing an enlarged main part of the automatic thickness control stone polishing apparatus shown in FIG.

FIG. 4 is a side view showing a thickness measuring device.

5 is a front view of the thickness measuring instrument shown in FIG.

FIG. 6 is a circuit diagram showing a control circuit of the thickness measuring instrument.

FIG. 7 is an explanatory diagram showing the measurement principle of the present invention.

[Explanation of sign]

 1 Front-rear guide rail 2 Front-rear traveling platform 3 Left-right guide rail 4 Left-right traveling platform 5 Lifting mechanism 6 Spindle mounting base 8 Spindle 13 Polishing plate holding part 14a Polishing plate 17 Surface plate 19 Stone 20 Measuring surface 22 Thickness measuring device 24 Feed screw shaft 26 Pulse motor 29 Lift block 30 Sensor mount 32 Limited reflection type distance sensor 33 Wire drawing linear encoder 34 Wire 35 Air jet nozzle 36 Water-repellent blade 40 Control device 45 Polishing device control unit 46 Grinding water

Claims (3)

[Claims] 1. A combination of front and rear guide rails and left and right guide rails, an elevating mechanism is provided on a traveling base guided by the left and right guide rails, and a main spindle mounting base is attached here to support the main spindle in a three-dimensionally movable manner. A polishing disk is attached to the lower end of the main spindle, and a stone polishing apparatus for planarly polishing the upper surface of the stone while jetting grinding water, to the main spindle mount to which the main spindle is attached,
The feed screw shaft is mounted vertically along the main axis, and the sensor mount is provided on the lifting block screwed to this feed screw shaft.The non-contact distance sensor is placed at the lower end of this sensor mount close to the stone measurement surface. In addition to mounting, the upper end of the sensor mounting base is connected to the moving distance measuring device mounted on the horizontal traveling base, and the non-contact distance sensor's vertical moving distance and non-contact distance measured by this moving distance measuring device. A control device is provided that detects the height of the top surface of the stone from the total distance between the sensor and the stone measurement surface and stops the spindle when the stone reaches the set thickness, and further below the sensor mount. The water-repellent blade that makes sliding contact with the measurement surface at the lower end is attached to the polishing plate side, and the air injection nozzle is attached to the non-contact distance sensor side on this side facing the measurement surface. Automatic thickness control stone polishing apparatus. 2. A moving distance measuring device mounted on a traveling platform in the left-right direction is composed of a wire pull-out type linear encoder,
The thickness measuring instrument of the stone polishing apparatus according to claim 1, wherein the lower end of the wire pulled out from this is connected to the sensor mount. 3. The non-contact distance sensor is formed of a limited reflection type distance sensor that outputs a position holding signal when the amount of light reflected by a measurement surface of a stone material reaches a maximum value at a predetermined distance. The automatic thickness control stone polishing device according to claim 1.