JPH02106266A - Device for automatically applying grinding wheel - Google Patents

Abstract

PURPOSE:To carry out a dressing operation continuously and automatically by displacing a holding mechanism for holding a grinding wheel via a robot arm to carry out a grinding-wheel applying operation while providing a dressing mechanism for dressing the grinding wheel and a remaining quantity detecting mechanism for detecting whether or not the grinding wheel has a defined wall thickness. CONSTITUTION:A grinding-wheel applying operation is carried out onto the machining face of a workpiece W by means of a grinding wheel 34 installed on a holding mechanism 36 via a robot 32. On the other hand, a dressing operation and a remaining quantity detecting operation for the grinding wheel 34 is executed automatically and continuously via a dressing mechanism 38 and a remaining quantity detecting mechanism 40 for each defined time. Hence, the whole grinding-wheel applying operation can be executed automatically and efficiently while keeping the grinding wheel 34 always in the optimum condition, to enable the execution of a high-quality grinding-wheel applying operation.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to an automatic grindstone racking device, and more specifically, a robot arm that is movable along a predetermined trajectory and is supported by a floating robot via a gripping mechanism. While removing cutting debris and debris from the machined surface of the workpiece using a grinding wheel, the grinding wheel is dressed under the movement of the robot arm, and the remaining amount of the grinding wheel is detected to determine whether it can be used. This invention relates to an automatic grindstone device which is configured to determine whether or not the workpiece is to be used.

[Background of the Invention] Generally, various machining operations are performed on a workpiece in a factory, and at that time, cutting waste, dents, bumps, etc. are often present on the machined surface of the workpiece. Therefore,
Normally, the machined surface of the workpiece after processing is polished to remove cutting debris, burrs, etc. from the machined surface.

Therefore, in the past, various devices have been proposed to automatically carry out the work of this type of grindstone rack, and the technical idea thereof is disclosed in, for example, Japanese Utility Model Application Publication No. 61-148558. This is shown in FIG.

That is, a slide base 4 is engaged with the first cylinder 2, and the slide base 4 is supported on both sides by guide rails 6a and 6b. A second cylinder 8 is held at the lower end of the slide base 4 and extends vertically downward, and an elevating plate 10 is engaged with a piston rod 8a extending from the cylinder 8.

One end of a support rod 12 is held on this elevating plate 10, and this supporting rod 12 fits into a guide groove 13 formed in the longitudinal direction of the guide rail 6b to prevent rotation of the elevating plate 10. To carry out the functions of

One end of support poles 14a, 14b is fitted into the lifting plate 10, and a holding plate 1 is fitted to the other end of the support poles 4a, 14b.
6 is engaged, and the respective support bolts 14a, 14
Spring members 18a and 18b are interposed in b, and the elevating plate 10 is attached to the elevating plate 10 via nut members 20a and 20b so as to be movable forward and backward. Further, a grindstone 22 is fixed to the holding plate 16.

In such a configuration, first, the elevating plate 10 is lowered under the driving action of the second cylinder 8, and the grindstone 22 fixed to the holding plate 16 is moved with a predetermined pressing force through the elastic force of the spring member 18a118b. Bring it into contact with the surface of W. Next, the first cylinder 2 is driven to move the slide base 4 onto the guide rail 5a.

While reciprocating in the horizontal direction under the guiding action of 6b,
By conveying the workpiece W in a predetermined direction, the grindstone 2
2, the workpiece W is ground with a whetstone.

By the way, in the prior art described above, the holding plate 16 to which the grindstone 22 is fixed is substantially supported by the elevating plate IO by two support bolts 14a and 14b.

Therefore, when an attempt is made to press one corner of the grindstone 22 against the corner of the work W in order to grind the corner of the work W, the grindstone 22 is pressed as shown by the two-dot chain line in FIG. There is a risk that it will tilt.

As a result, it has been pointed out that there are disadvantages in that the grindstone 22 cannot be applied to the vicinity of the corners of the workpiece W, and the corners are rounded.

Moreover, since the grindstone 22 is fixed to the holding plate 16 by, for example, bolting, the size of the grindstone that can be used is limited, and if the bolts are tightened firmly, the grindstone 22 may be damaged. This poses a risk of being lost.

Furthermore, as the grindstone 22 is used to grind the workpiece W, the grindstone 22 becomes clogged, so it is necessary to periodically dress the grindstone 22. that time,
Substantially, the worker himself performs the dressing work of the grindstone 22, and the above-mentioned grindstone rack has a drawback in that the entire work cannot be automated.

On the other hand, if the use of the grindstone 22 continues, the grindstone 22 itself will wear out. When the remaining amount of the grindstone 22 becomes less than a predetermined amount, it is not possible to reliably remove burrs and the like generated on the workpiece W, resulting in variations in processing quality.

As a result, it becomes necessary for the operator to confirm the remaining amount of the grindstone 22, and a problem has emerged in which it becomes even more difficult to automate the grindstone work.

[Object of the Invention] The present invention has been made to overcome the above-mentioned disadvantages, and includes a method in which a holder to which a grindstone is fixed is supported in a floating manner at at least four locations using a fastening member of a model, and is attached to a robot arm. a gripping mechanism that is freely displaceable; a dressing mechanism that automatically performs dressing work on the grindstone;
By providing a remaining amount detection mechanism that detects whether or not the grindstone has a predetermined thickness, the grindstone can be maintained in a suitably usable state at all times, and the grindstone rack automatically performs the work. The purpose of the present invention is to provide an automatic grinding device that can perform the grinding process efficiently and with high precision.

[Means for Achieving the Object] In order to achieve the above-mentioned object, the present invention provides a gripping mechanism for removably supporting a grindstone and grinding a workpiece under the displacement action of a robot arm; a dressing mechanism for automatically dressing a work surface of the
The present invention is characterized by comprising a grindstone remaining amount detection mechanism for automatically detecting whether the thickness of the grindstone is within a predetermined range.

[Embodiments] Next, preferred embodiments of the automatic grinding device according to the present invention will be described in detail with reference to the accompanying drawings.

In FIG. 2, reference numeral 30 indicates an automatic whetstone rack device according to this embodiment, and the automatic whetstone rack device 30 is attached to a robot 32 and holds a whetstone 34 so as to be freely displaceable in a predetermined direction. It basically consists of a gripping mechanism 36, a dressing mechanism 38 for performing dressing work on the grindstone 34, and a remaining amount detection mechanism 40 for detecting the state of wear of the grindstone 34. In this case, the dressing mechanism 38 and the remaining amount detection mechanism 40 are placed on the upper part of the workbench 42 and positioned outside both of the workpieces W transported via the pallet 44.

The robot 32 includes a base 48 that can move forward and backward in the direction of the arrow on a rail 46, and a rotatable main body 5 is mounted on the base 48.
0 is placed. A first arm 52 that is swingable in the direction of the arrow is engaged with the main body 50, and a second arm 54 that is swingable in the direction of the arrow is connected to the end of the first arm 52.

Further, a wrist portion 56 is engaged with the distal end portion of the second arm 54 so as to be swingable in the direction of the arrow.
A gripping mechanism 36 is attached to.

As shown in FIGS. 3 and 4, the gripping mechanism 36 has a rectangular casing 58 with a U-shaped cross section;
The flat surface of the casing 58 has holes 60a to 60d located at positions substantially corresponding to the vicinity of the corners of the grindstone 34.
is drilled. Support rods 62a to 62dJ fit into the holes 60a to 60d, and the holder 64 is supported by the casing 58 via the support rods 62a to 62d. That is, the holder 64 has a rectangular shape, and its outer dimensions are selected so as to define a predetermined gap between the holder 64 and the inner wall surface of the casing 58. Recesses 66 and 68 are formed on both upper and lower surfaces of the holder 64, and a long inner wall surface 70a and a short inner wall surface 70b that define the recess 68 are inclined outwardly with respect to the downward direction. .

Furthermore, a wall 71 that blocks the recesses 66 and 68 is provided with screw holes 72a to 72d at positions corresponding to the holes 60a to 60d of the casing 58, and screw holes 74a and 72d are formed at predetermined positions, respectively. 74b, 76a, 76b and a hole 78 are formed. A detection means 80 such as an optical sensor is attached to the hole 78, and the presence or absence of the grindstone 34 is detected via this detection means 80. In this case, the grindstone 34 is selected to be substantially smaller in size than the recess 68 of the holder 64, and has a substantially rectangular shape.

Therefore, the first fastening member 82 of the model is disposed on the elongated inner wall surface 70a that defines the recess 68. An inclined surface 84 corresponding to the inclination of the inner wall surface 70a is formed on one side of the first fastening member 82, and at positions corresponding to the respective screw holes 74a and 74b there are provided holes for loosely fitting bolts to be described later. Holes 86a and 86b are bored. On the other hand, the short inner wall surface 70
A second fastening member 88 is disposed at b, and this second fastening member 88 is formed with an inclined surface 90 corresponding to the inner wall surface 70b, and has hole portions 9 corresponding to the respective screw holes 76a and 76b.
2a and 92b are drilled. In addition, square pads 94 and 96 made of a resin material such as acetal resin are provided on the long and vertical inner wall surface and the short and vertical inner wall surface that define the recess 68, respectively. Therefore, the first and second
Holes 86a186b and 92a of connecting member 82.88
, 92b are loosely fitted with bolts 98a to 98d, and their tips are screwed into the screw holes 74a, 74b and 76a, 76b to hold the grindstone 34 in the holder 64.

Next, threaded portions 100a to 100d and 102a to 102d are formed at both ends of the support rods 62a to 62d, and the threaded portions 100a to 100d are screwed into the screw holes 72a to 72d. And the support rod 62
Coil springs 104a to 104d from a to 62d
and the holes 60a to 6 of the casing 58.
The flanged nut members 106a to 106d are fitted into the threaded portions 102a to 102d exposed above 0d.

In this case, the diameter of each nut member 106a to 106d is selected to be larger than the diameter of the hole 60a to 60d, so that the holder 64 is supported in a floating state by the casing 58.

As shown in FIGS. 5a and 5b, the dressing mechanism 38
has a support 108 erected on the workbench 42, and a pedestal 110 is placed on top of this support 108. Said pedestal 1
For example, a dressing grindstone 112 containing diamond abrasive grains is attached to the dressing grindstone 10 , and a pressurized fluid such as air is introduced to the grindstone 34 on the side of the pedestal 110 .
A nozzle member 114 for cleaning the processing surface of No. 4 is attached.

This nozzle portion 114 is provided with a fluid outlet passage 116, and one end of this passage 116 communicates with a conduit 118 connected to a fluid supply source (not shown), while the other end of the passage 116 is vertical. It opens upward.

The remaining amount detection mechanism 40, as shown in FIGS. 6a and 6b,
It has a support 120 erected on the workbench 42, and a flat portion 1 is provided at a predetermined depth position from the upper end surface 120a of the support 120.
22 is formed. A service hole 126 is bored in the center of the plane portion 122, and the movable rod 1 is inserted into the stepped hole 126.
28 fits loosely. A large diameter portion 130 having a larger diameter than the service hole portion 126 is formed at the upper portion of the movable rod 128, and a detection member 132 is attached to the lower end of the movable rod 128.

A coil spring 134 is interposed between the large diameter portion 130 and the bottom wall portion defining the stepped hole portion 126, and the movable rod 128 is moved to a predetermined height position through the elastic force of the coil spring 1340. Position it.

Here, the support 120 has a detection means 13 such as a proximity switch.
6 is provided, and this detection means 136 is positioned at a position to detect the detection member 132 when no external force is applied to the movable rod 128 (see FIG. 6a). Note that the detection member 132 may be arranged above the detection means 136 and not detected by the detection means 136 when no external force is applied to the movable rod 128.

In any case, when the grindstone 34 having a desired wall thickness engages with the movable rod 128, the detection member 132 is activated by the detection means 136.
It is only necessary to move it downward away from the detection range of .

The automatic grinding device according to this embodiment is basically constructed as described above, and its operation and effects will be explained next.

First, the operation of mounting the grindstone 34 on the holder 64 will be explained. That is, the pads 94 and 96 are brought into contact with the vertical inner wall surfaces defining the recessed portion 68 of the holder 64, and the negative long and short sides of the grindstone 34 are brought into contact with the pads 94 and 96, respectively. On the other hand, first and second fastening members 82.88 are fitted between the other long side and short side of the grindstone 34 and the inner wall surfaces 70a, 70b, respectively.
holes 86a, 86b.

Loosely fit the bolts 98a to 98d into the bolts 92a and 92b, and insert the respective tips into the screw holes 74a, 74b, 76a, 76.
Screw into b.

At this time, each fastening member 82.88 has an inclined surface 84.9.
0, and when the inclined surface 84.90 engages with the inner wall surfaces 70a, 70b which are also inclined at the same angle, the fastening member 82.88 moves toward the grindstone 34. Therefore, the grindstone 34 is pressed toward the respective pads 94,96, and the respective fastening members 82,88 and the pads 94
．． 96, it is firmly pressed and held from four directions and is securely attached to the holder 64. Here, in particular, since the pads 94 and 96 are made of a resin material such as acetal resin, the above-mentioned advantage of being able to prevent the grindstone 34 from being damaged when the grindstone 34 is attached becomes apparent.

Moreover, since the respective fastening members 82 and 88 move and hold the four corners of the whetstone 34, it is possible to easily accommodate a certain degree of variation in the dimensions of the whetstone 34. You can also use a whetstone.

Therefore, after completing such preparatory work, the workbench 42
A workpiece W is transported to a predetermined position via a pallet 44. Next, the robot 32 is driven to move the main body 50
, by displacing the first arm 52, the second arm 54, and the wrist portion 56 in predetermined directions, respectively.
The grindstone 34 works on the processing surface of the workpiece W via a gripping mechanism 36 attached to the grindstone.

At this time, the grindstone 34 is supported in a floating state via the holder 64 and the casing 58 via four support rods 62a to 62d. For this reason, even if the area of the machined surface of the workpiece W is relatively small or when the grindstone is used for the corner portion of the machined surface, the grindstone 34
can be held reliably in the horizontal direction, and the corner portion of the grindstone 34 allows the work to be performed on the processing surface of the workpiece W or the grindstone on the corner portion.

That is, the support rods 62a to 62d are arranged substantially as close as possible to the four corners of the grindstone 34, and even if one corner of the grindstone 34 is pressed against a corner of the workpiece W, The grindstone 34 does not tilt unnecessarily under the force of the springs 104a to 104d mounted on the respective support rods 62a to 62d. Therefore, one corner of the grinding wheel 34 can be reliably engaged with the corner of the workpiece W, and it is possible to prevent problems such as rounding of the corner of the workpiece W. It will be done. Further, since the holder 64 holding the grindstone 34 is supported in a floating state by the casing 58 via the coil springs 104a to 104d, even if the machining surface of the workpiece W is inclined, the grindstone 34 can be It becomes possible to engage accurately with the machined surface of W.

Furthermore, a detection means 80 is attached to the holder 64, and the presence or absence of the grindstone 34 is detected via this detection means 80. Therefore, when the grindstone 34 is damaged and falls during operation of the robot 32, this information can be automatically and quickly detected and the drive of the robot 32 can be immediately stopped.

After the work of the grinding wheel on the machining surface of the work W is completed in this way, the work W is transported to the next working position via the pallet 44, and the grinding wheel of the device 30 is moved to the working position. A pallet 44 carrying a new workpiece W is conveyed.

By the way, since the grindstone 34 of the workpiece W becomes clogged as the work continues, the grindstone 34 is periodically subjected to a dressing operation. That is, the robot 32 is driven to displace the gripping mechanism 36 toward the dressing mechanism 38, and as shown in FIG. Apply dressing to the surface. next,
When the grindstone 34 moves in the direction of the arrow and reaches the nozzle member 114 side, a pressure fluid, for example, pressurized air, is introduced into the passage 116 from a fluid supply source (not shown) connected to the pipe line 118, and this pressurized air is The liquid is sprayed from the vertically upwardly open end of the passage 116 onto the work surface of the grindstone 34 after dressing has been completed.

Therefore, the abrasive grains adhering to the working surface of this grindstone 34 are removed, and if the grinding wheel 34 of the workpiece W is restarted after the dressing is finished, there will be no unnecessary adhesion on the working surface of this grindstone 34. Since there is no kimono, a highly accurate grindstone can be used on the workpiece W.

On the other hand, as the device 30 continues to work on the workpiece W, the grindstone 34 itself becomes worn out. Therefore, the remaining amount detection mechanism 4 periodically checks the wear state of the grindstone 34.
Detected by 0. That is, the gripping mechanism 36 is moved toward the remaining amount detection mechanism 40 under the driving action of the robot 32, and the gripping mechanism 36 is displaced downward from above the column 120 that constitutes the remaining amount detection mechanism 40. Therefore, as shown in FIG. 6, the grindstone 34 presses the large diameter portion 130 provided at the top of the movable rod 128 vertically downward, and the movable rod 128 is affected by the elastic force of the coil spring 1340. It resists and is displaced in the direction of the arrow. Then, when the end surface of the holder 64 holding the grindstone 34 comes into contact with the upper end surface 120a of the support column 120, the movable rod 128 is wiped and positioned at a position corresponding to the thickness of the grindstone 34.

Here, if the detection member 132 attached to the lower side of the movable rod 128 moves out of the detection range of the detection means 136 (see Figure 6), the wall thickness of the grindstone 34 becomes sufficient for the grinding operation. It is detected that the material has a certain thickness. On the other hand, if the detection member 132 is within the detection range of the detection means 136,
It is detected that the grindstone 34 is unsuitable for use,
Therefore, the grindstone 34 is replaced with a new one.

Therefore, there is no risk of grinding the workpiece W in a state where the grindstone 34 is worn down to a predetermined amount or less, and it is possible to prevent deterioration of the accuracy of the grinding work on the machined surface of the workpiece W.

In this manner, in this embodiment, the grindstone 34 attached to the gripping mechanism 36 is operated by the robot 32 on the processing surface of the workpiece W, and the dressing mechanism 38 and the remaining amount detection mechanism are 40, the dressing work of the grindstone 34 and the work of detecting the remaining amount are automatically and continuously carried out. Therefore, the grindstone rack can carry out the entire work automatically and efficiently, and the grindstone rack 34 can always be maintained in an optimum condition to carry out the work with high quality. Moreover, by detecting whether or not the whetstone 34 is held in the holder 64 by the detection means 80 provided on the holder 64, it is possible to immediately detect an accidental fall of the whetstone 34, and Gripping mechanism 3 that does not hold the grindstone 34
This makes it possible to prevent the inconvenience of operating 6 unnecessarily.

[Effects of the Invention] As described above, according to the present invention, the gripping mechanism that holds the grindstone is displaced via the robot arm to set the workpiece on the grindstone, and the dressing mechanism that dresses the grindstone is also provided. , and a remaining amount detection mechanism for detecting whether or not the grindstone has a predetermined wall thickness. Therefore, the effect that the dressing of the workpiece can be carried out continuously and automatically can be obtained. Moreover, the gripping mechanism holds the grindstone at least 4 times in a floating state.
Since the grindstone is supported at certain points, the grindstone does not tilt unnecessarily, and the grindstone rack can perform work reliably and with high precision along the processing surface of the workpiece. Furthermore, the grindstone can be firmly held to the holder by the fastening member of the model, facilitating the work of replacing the grindstone, and preventing the grindstone from being damaged or falling from the holder during the replacement work. becomes possible.

Although the present invention has been described above with reference to preferred embodiments, the present invention is not limited to these embodiments.
Of course, various improvements and changes in design are possible without departing from the gist of the present invention.

[Brief explanation of drawings]

FIG. 1 is a schematic side view of an automatic whetstone rack according to the prior art; FIG. 2 is a schematic configuration diagram of the automatic whetstone rack according to the present invention; and FIG. 3 is a gripper that constitutes the automatic whetstone rack. FIG. 4 is a vertical cross-sectional view of the gripping mechanism shown in FIG. 3; FIGS. 5 a and b are schematic cross-sectional views of the dressing mechanism that constitutes the automatic grinding wheel device; FIG. 6 is an exploded perspective view of the mechanism; Figures a and b are longitudinal cross-sectional views of the remaining amount detection mechanism that constitutes the automatic whetstone device.

Claims (8)

[Claims] (1) A gripping mechanism that detachably supports the grindstone and applies the grindstone to the workpiece under the displacement action of the robot arm;
The grinding wheel includes a dressing mechanism for automatically dressing the working surface of the grinding wheel, and a grinding wheel remaining amount detection mechanism for automatically detecting whether the wall thickness of the grinding wheel is within a predetermined range. An automatic grinding device characterized by: (2) The device according to claim 1, wherein the gripping mechanism includes a casing attached to the robot arm and a holder that holds a polygonal grindstone, and the holder is placed near each corner of the grindstone with respect to the casing. What is claimed is: 1. An automatic grinding device that is compatible with the above and is configured to be supported in a floating state via elastic bodies at at least four locations. (3) The apparatus according to claim 2, wherein the holder is provided with a recess for accommodating the grindstone, and a tapered surface is formed on one or more inner wall surfaces defining the recess, and an inclined surface corresponding to the tapered surface. An automatic grinding device characterized in that it is configured to press and hold the grindstone in a recess of a holder via one or more fastening members that form and engage with the grindstone and a pad. (4) The automatic grinding device according to claim 3, wherein the pad is preferably made of a resin-based material having a hardness substantially lower than that of the grindstone. (5) An automatic grinding device according to claim 2 or 3, characterized in that the holder is provided with a detection means for detecting the presence or absence of a grindstone. (6) In the apparatus according to claim 1, the dressing mechanism includes a dressing grindstone that substantially dresses the grindstone, and a nozzle member that injects pressure fluid to the grindstone after finishing the dressing to clean the grindstone. An automatic grinding device characterized by comprising: (7) In the device according to claim 1, the remaining amount detection mechanism includes a movable rod that engages with the grindstone and can move forward and backward, and a detection means that is driven by displacement of the movable rod, and the detection means detects the An automatic grinding device characterized in that it is configured to detect whether the wall thickness of a grindstone is within a predetermined range. (8) The automatic grinding device according to claim 7, characterized in that the end of the holder holding the grinding wheel is used as a reference for positioning the grinding wheel with respect to the remaining amount detection mechanism.