JPH03121777A - Rotary dresser - Google Patents

Abstract

PURPOSE:To reduce the noise generated at the rotation time of an impeller and to improve the safety of a dressing work time, by covering the impeller with a cover. CONSTITUTION:A rotating grinding wheel G is rotated in the state of its separating from a dressing wheel 5, in case of the operation of a rotary dresser. The dressing wheel 5 is then rotated at the peripheral speed different from that of the rotating wheel G by rotating a rotating shaft 3 by blowing a compressed air A to an impeller 16 and also operating a brake means (brake shoe) 11. When the dressing wheel 5 and rotating wheel G are brought into contact in this state, the shaping of the rotating wheel G is performed with the peripheral speed difference in the rotations between both wheels. In this case, the impeller 11 is safe because of its almost whole body being covered by a cover 15, and yet the noise generated at the rotation time is cut off by this cover 15.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to the structure of a rotary dresser that performs shaping by bringing a drainage grindstone into contact with a rotary grindstone for grinding a workpiece.

[Prior art] Conventionally, this type of rotary dresser was
There is one disclosed in Publication No. -4560. As shown in FIG. 4, a rotating shaft 32 is supported by the main body case 31 of this rotary dresser, and both front and rear (left and right in the figure) ends of the rotating shaft 32 protrude from the main body case 31. A dressing grindstone 33 is attached to the front end of the rotary shaft 32 for shaping the lower part of the rotation for grinding the workpiece, and an impeller 34 is attached to the rear end of the rotary shaft 32.

Therefore, the impeller 34 is exposed outside the main body case 31.

One nozzle 35 is arranged near the side of the impeller 34, and the impeller 34 is rotated by the compressed air A blown out from this nozzle 35. On the other hand, the rotary dresser is equipped with a braking means 36, and when the circumferential speed of the dressing grindstone 33 becomes larger than a predetermined value, the braking means 36 applies a braking force to the rotating shaft 32.
As a result, the circumferential speed of the dressing grindstone 33 is controlled.

When using the rotary dresser, the rotary grindstone G is rotated while being separated from the dressing grindstone 33. Then, the compressed air A is blown onto the impeller 34 through the nozzle 35 to rotate the rotary shaft 32, and the braking means 36 is operated so that the circumferential speed of the dressing grindstone 33 is slightly different from the circumferential speed of the rotary grindstone G. The rotation of the dressing grindstone 33 is controlled. Next, dressing whetstone 3
3 and the rotating grindstone G are brought into contact. Then, the dressing whetstone 33 quickly adapts to the rotation of the rotary whetstone G without strongly repelling it and rotates, making it possible to reduce the impact upon contact. The surface layer of the rotary grindstone G is scraped off to perform shaping.

[Problems to be Solved by the Invention] However, in the conventional rotary dresser, since the impeller 34 rotates while being exposed from the main body case 31 during the dressing operation, there are problems with safety during the operation. Therefore, if a foreign object or the like hits the rotating impeller 34, there is a risk of damage. Furthermore, the impeller 3
There is also the problem that the noise generated by 40 rotations is large, leading to deterioration of the working environment.

Further, since only one nozzle 35 for spraying the compressed air A onto the impeller 34 is provided, there is a problem in that the circumferential speed of the impeller 34 is difficult to adjust.

The purpose of the present invention is to improve safety during dressing work,
Another object of the present invention is to provide a rotary dresser that can reduce the noise generated when the impeller rotates, and furthermore, to provide a rotary dresser that can easily adjust the circumferential speed of the impeller. be.

[Means for Solving the Problems] Therefore, in order to achieve the above object, the present invention provides a rotating grindstone that is attached to a rotating shaft supported by a main body case and that is in a rotating state in order to shape a rotating grindstone for grinding a workpiece. a dressing grindstone that comes into contact with the grindstone; an impeller that is fixed to a rotating shaft exposed from the main body case and rotates by being blown with compressed air supplied from a pressure source; and a cover that covers almost the entirety of the impeller. The gist of the present invention is a rotary dresser including a braking means for applying a braking force to a rotating shaft in order to rotate the dressing grindstone at a circumferential speed slightly different from the circumferential speed of the rotary grindstone.

In addition, a plurality of nozzles for blowing compressed air to the impeller are provided on the cover, and a flow rate adjustment means is provided between each nozzle and the pressure source to control the flow rate of the compressed air blown out from the nozzle. It is preferable.

[Operation] When operating the rotary dresser, the rotary grindstone is rotated in a state separated from the dressing/nosing grindstone. and,
By blowing compressed air onto the impeller to rotate the rotating shaft and activating the braking means, the dressing grindstone is rotated at a circumferential speed different from the circumferential speed of the rotary grindstone. When the dressing whetstone and the rotary whetstone are brought into contact in this state, the rotary whetstone is shaped by the difference in peripheral speed of rotation between the two whetstones.

Since the impeller is almost entirely covered and protected by the cover, it is safe, and the noise generated during its rotation is blocked by the cover.

In addition, since multiple nozzles and flow rate adjustment means are provided, it is possible to individually adjust the flow rate of compressed air blown out from each nozzle.
A adjustment becomes easy.

[Example] An example embodying the present invention will be described below with reference to FIGS. 1 to 3.

As shown in Fig. 1, the main body case 1 of the rotary dresser
A mounting hole 2 extending front and rear (left and right in FIG. 1) is formed in the mounting hole 2, and a rotating shaft 3 is inserted through the mounting hole 2. Bearings 4 are installed at both the front and rear ends of the mounting hole 2, and the rotating shaft 3 is rotatably supported by the main body case 1 via these bearings 4.

A disc-shaped dressing whetstone 5 is fixed to the front end of the rotary shaft 3 protruding forward from the main body case 1, and the dressing whetstone 5 rotates integrally with the rotary shaft 3. A front cover 6 with an open upper part is attached to the front part of the main body case 1, and the dressing grindstone 5 is exposed from the open part of the front cover 6.

Therefore, by bringing this dressing whetstone 5 into contact with the rotary whetstone G for grinding the workpiece shown by the two-dot chain line in FIG. 1, the rotary whetstone G can be shaped.

As shown in FIGS. 1 and 2, a brake cover 7 is attached to the rear of the main body case 1.

This brake cover 7 is formed with a housing recess 8 having a circular opening on the front surface, and the inner circumferential surface of the housing recess 8 constitutes a sliding surface 8a. A rotating body 9 having a diameter slightly smaller than the inner diameter of the housing recess 8 is fixed on the rotating shaft 3 passing through the accommodation recess 8, so that the rotating body 9 rotates integrally with the rotating shaft 3. It has become.

The rotating body 9 has three recesses 10 opened at its outer peripheral surface and extending toward the center of the rotary body 9 at equal angles (120° in this case). A shoe 11 is housed in a retractable manner. Each brake shoe 11 is provided with a mounting hole 12, and a bolt 13 disposed in each mounting hole 12 passes through the bottom wall of the brake shoe 11 and is fixed to the rotating body 9. A compression coil spring 14 is interposed between the head of the bolt 13 and the bottom wall of the brake shoe 11, and this compression coil spring 14 causes the brake shoe 11 to move toward the center of the rotating body 9, which is the retracting direction. Always energized.

Therefore, each of the brake shoes 11 is compressed by the compression coil spring 1 due to the centrifugal force generated when the rotating body 9 is rotated.
4 protrudes from the recess 10 and comes into pressure contact with the sliding surface 8a of the brake cover 7. These sliding surfaces 8a and brake shoes 11 constitute a braking means that applies a braking force to the rotating shaft 3.

As shown in FIG. 1.3, an impeller 16 is fixed to the rotating shaft 3 that projects rearward from the brake cover 7, and this impeller 16 rotates integrally with the rotating shaft 3. ing. The impeller 16 includes a boss portion 16a externally fitted and fixed to the rotating shaft 3, a disk portion 16b formed at the front portion of the boss portion 16a, and a circular plate portion 16b formed in a straight line in the radial direction at equal angles around the boss portion 16a. It is composed of a plurality of (five in this embodiment) extending blade portions 16C.

A rear cover 15 is attached to the rear end of the brake cover 7, and the impeller 16 is
is almost entirely covered. Communication holes 18 are transparently provided at two locations on the side of the rear cover 15 to communicate the inside and outside of the rear cover 15, and compressed air A is introduced from nozzles 20 and 21 attached to each communication hole 18. It has become. In addition, a discharge hole 17 is transparently provided in the center of the rear cover 15.
The rear end of the rotary shaft 3 is inserted into the discharge hole 17, and the compressed air A introduced into the rear cover 15 is
The liquid is discharged from the gap between these discharge holes 17 and the rotating shaft 3.

By the way, a compressor 19 as a pressure source is disposed near the row redresser, and this compressor 1
9 and the nozzle 20.21 are connected by air pipes 22.23, respectively, and the compressor 19
Compressed air A supplied from is blown out from each nozzle 20.21.

Each of the air pipes 22 and 23 is provided with an on-off valve 24 for allowing and stopping the supply of compressed air A to the nozzles 20 and 21.
A pressure reducing valve 25 for maintaining the air pressure of the compressed air A constant is also provided. Further, each air pipe 22.23 is provided with a flow rate adjustment valve 26.27 as a flow rate adjustment means, and by adjusting these, the flow rate of compressed air A blown out from each nozzle 20.21 is controlled. It is possible to change the circumferential speed of the impeller 16, that is, the dressing grindstone 5, as appropriate.

Next, a method of shaping the rotary grindstone G for grinding a workpiece using the row redresser configured as described above will be described.

First, during this work, the rotary grindstone G is rotated in a state separated from the dressing grindstone 5.

Then, in this state, the compressor 19 is operated to open the on-off valves 24 in each air pipe 22, 23. Then, compressed air A flows from the compressor 19 to the air pipe 22.
23 to each nozzle 2021, and is sprayed onto the blade portion 16c of the impeller 16 in the rotary dresser.

When the compressed air A is blown from each nozzle 20, 21 as described above, the impeller 16 begins to rotate together with the rotating shaft 3, rotating body 9, and dressing grindstone 5. At this time, the brake shoe 11 is retracted into the recess 10 of the rotating body 9, and no braking force is applied to the rotating shaft 3. Note that the compressed air A blown onto the impeller 16 as described above is discharged to the rear of the rear cover 15 through the discharge hole 17.

Compressed air A from each nozzle 20.21 causes the impeller 16 to
When the rotational speed of the rotating body 9 gradually increases and exceeds a predetermined speed, the centrifugal force generated due to the rotation of the rotating body 9 causes the brake shoe 11 in the recess 10 of the rotating body 9 to
It protrudes from the recess 10 against the biasing force of the compression coil spring 14 and comes into pressure contact with the sliding surface 8a of the brake cover 7. Therefore, a braking force acts on the rotating shaft 3.

The circumferential speed of the dressing grindstone 5 at this time is different from the circumferential speed of the rotary grindstone G, and needs to be adjusted to a value close to the circumferential speed of the rotary grindstone G. In this embodiment, the nozzle 20. 21 are provided, and the flow rate to the compressed air blown out from each nozzle 20.21 is controlled by adjusting the flow rate adjustment valves 26.27. This makes it easier to control the circumferential speed. Furthermore, in addition to adjusting the flow rate of the compressed air A from the two nozzles 20 and 21, the braking force from the brake shoes 11 is added, so the synergistic effect of these two makes it easier to control the circumferential speed of the impeller 16.

When the circumferential speed of the dressing grindstone 5 is controlled to a predetermined value as described above, the rotating grindstone G for grinding is brought into contact with the dressing grindstone 5. At this time, since the circumferential speed of the dressing grindstone 5 and the circumferential speed of the rotary grindstone G are only slightly different, both grindstones 5
．． The impact upon contact with G is small. And both whetstones 5
．． Due to the difference in circumferential speed of G, the surface layer of the rotary grindstone G is scraped off and shaped.

By the way, when the compressed air A is sprayed from the two nozzles 20 and 21 to rotate the impeller 16 as described above, noise is generated as the impeller 16 rotates. 16 is covered with the rear cover 15, the noise is blocked and difficult to leak to the outside of the rotary dresser, thereby improving the working environment.

Furthermore, if the impeller 16 is exposed from the rotary dore nosa, it not only poses a problem in terms of work safety;
If a foreign object or the like hits the impeller 16 while it is rotating, it may be damaged, so it is necessary to take some measures to prevent this. However, in this embodiment, as described above, this impeller 16 is covered with the rear cover 15, so safety is improved.
There is no need to install new separate parts.

It should be noted that the present invention is not limited to the configuration of the above-mentioned embodiments. 1 degree or the number of brake shoes 11, etc., it is possible to make arbitrary changes and embodiments without departing from the spirit of the invention.

Further, the rear cover 15 may be provided with three or more nozzles.

[Effects of the Invention] As detailed above, according to the rotary dresser of the present invention, since the impeller is covered with a cover, safety during dressing work is improved and noise generated when the impeller rotates is reduced. This has the effect of making it possible to achieve the following.

Further, since a plurality of nozzles are provided on the cover and a flow ff1gF] node is provided between each nozzle and the pressure source, the circumferential speed of the impeller can be easily controlled.

[Brief explanation of drawings]

1 to 3 show an embodiment embodying the present invention.
The figure is a sectional view of a rotary dresser, Figure 2 is a sectional view taken along line nn in Figure 1, Figure 3 is a sectional view taken along line m-m in Figure 1, and Figure 4 is a sectional view of a conventional rotary dresser. It is. DESCRIPTION OF SYMBOLS 1... Main body case, 3... Rotating shaft, 5... Dressing grindstone, 8a... Sliding surface forming part of braking means, 11... Brake forming part of braking means Shoe 15... Rear cover 16... Impeller, 19...
- Compressor as pressure source, 20.21... Nozzle, 26°27... Flow rate adjustment valve as flow rate adjustment means, A... Compressed air, G... Rotary grindstone.

Claims (1)

[Claims] 1. A rotating grindstone (G) attached to a rotating shaft (3) supported by a main body case (1) and in a rotating state for shaping the rotating grindstone (G) for grinding a workpiece. A dressing grindstone (5) that is in contact with the dressing grindstone (5), and a dressing grindstone (5) that is fixed to a rotating shaft (3) exposed from the main body case (1) and rotated by being blown with compressed air (A) supplied from a pressure source (19). an impeller (16); a cover (15) that covers almost the entire impeller (16); , a rotary dresser equipped with braking means (8a, 11) that applies braking force to the rotating shaft (3). 2. A plurality of nozzles (20, 21) for blowing compressed air (A) to the impeller (16) are provided on the cover (15), and a plurality of nozzles (20, 21) are provided between each nozzle (20, 21) and the pressure source (19). is a flow rate adjustment means (26, 2) for controlling the flow rate of compressed air (A) blown out from the nozzle (20, 21).
7) The rotary dresser according to claim 1, further comprising: 7).