JP2001232551A - Surface polishing device for particulate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a surface polishing device for particulate which prevents the occurrence of partial wear of a grinding wheel and does not need a large- scale dust collector. SOLUTION: The grinding wheel 14 supported on a support shaft 12 is rotated, a feed blade 30 is provided in a casing 22 storing the grinding wheel, and charged particulates W are transferred to a discharge port 44 while rotating the feed blade around the grinding wheel and are brought into contact with the rotating grinding wheel uniformly to polish surfaces of the particulates.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for polishing a surface of a granular material, and more particularly to an apparatus suitable for reclaiming molding sand.

[0002]

2. Description of the Related Art For example, when casting machine parts, a sand casting method is widely used from the viewpoint of manufacturing cost and production efficiency. Usually, sand obtained by polishing the surface of raw sand is used as the molding sand used for the sand mold. However, the molding sand after casting is regenerated, and only the regenerated sand or the regenerated sand may be used together with the raw sand. However, a binder and the like are kneaded in the foundry sand,
Since it is in a lump due to the high temperature at the time of casting, it is necessary to crush the lump of foundry sand and to remove the binder and the like adhering to the surface of the foundry sand when regenerating.

Conventionally, various methods have been proposed for polishing the surface of raw sand or used foundry sand. For example, a method in which raw sand or used foundry sand is jetted from an air nozzle and made to collide with an appropriate member (for example, a method disclosed in
50808), a method in which sand is thrown far and collided by centrifugal force caused by the rotation of the blades (see, for example, Japanese Patent Application Laid-Open No. 57-109540), and the sand is rubbed mutually in a rotary tank. There are known a method in which the sand is heated, a method in which the resin is adhered to the surface by heating the sand to burn and volatilize, and a method in which the sand is washed with water to wash away unnecessary substances on the surface.

[0004] However, any of the conventional methods is difficult to apply to a lump of sand, and its polishing ability is limited, so that it takes much time and effort to regenerate used molding sand. There is.

On the other hand, the applicants of the present invention have shown in FIGS.
As shown in FIG. 2, a plurality of disc-shaped polishing wheels 100
Are attached to the horizontal shaft 110 in a columnar manner, sand is injected from one end of the columnar grindstone 100, polished sand is discharged from the other end, and negative pressure is applied by the dust collector 120 from the other end, and the sand is injected. We developed a method to move the waste sand toward the discharge side and came to practical use.

[0006] Such a method has the advantage of high processing capacity because the surface can be polished while being crushed even if massive molding sand is directly introduced, and continuous processing can be performed.

[0007]

However, in the above-mentioned conventional method, the injected sand is moved from the input side to the discharge side mainly by the action of the negative pressure. The sand does not contact uniformly, and the sand and the grindstone are in intense contact on the input side, but the sand and the grindstone are not in good contact on the discharge side, and uneven wear is likely to occur on the grindstone. was there.

Further, since the input sand is moved to the discharge side by applying a negative pressure by the dust collector, a large-sized dust collector is required, and the equipment becomes large.

Further, when the surface of the sand is polished, fine powder is generated, and the fine powder is collected by a dust collector. However, the fine powder cannot be completely separated from the sand. There was a problem that the quality of the recycled sand was not good.

[0010] Further, when high-temperature molding sand immediately after casting is charged, there is a problem that the recycled molding sand is discharged at a high temperature, and it takes a long time to cool the molding sand with an external cooler.

SUMMARY OF THE INVENTION In view of the above problems, it is a first object of the present invention to provide an apparatus for polishing a surface of a granular material which does not cause uneven wear of a grindstone and does not require a large dust collector.
A second object of the present invention is to provide a granular surface polishing apparatus which can separate fine powder during surface polishing and can also cool molding sand.

[0012]

Therefore, the apparatus for polishing the surface of a granular material according to the present invention is brought into contact with a rotating grinding wheel,
In a granular surface polishing apparatus for polishing a surface of a granular material, a support shaft rotatably supported on an apparatus fixing structure portion, first driving means for rotating the support shaft, and an attachment to the support shaft The polishing grindstone having a substantially cylindrical shape as a whole, a casing that is supported concentrically with the polishing grindstone with respect to the device fixing structure portion, and that accommodates the polishing grindstone, is provided at one end in the longitudinal direction of the casing, An input port into which the granular material to be polished is input,
A discharge port provided on the other end side in the longitudinal direction of the caging and discharging the polished granular material, and provided in the casing, while rotating around the polishing grindstone, the charged granular material is A feed blade for transferring toward the discharge port,
And second driving means for rotating the feed blade.

One of the features of the present invention is that a feed blade is provided in a casing, and the fed granular material is transferred toward a discharge port by rotating the feed blade around a grinding wheel. It is in. As a result, the granular material charged into the casing is mechanically transported toward the discharge port by the feed blade, so that the granular material uniformly contacts the entire surface of the grinding wheel, and uneven wear occurs on the grinding wheel. Since there is no need to use a large-sized dust collector for transferring the granular material, it is possible to realize a reduction in size and cost of the equipment.

The first and second drive means may be of any type or structure as long as they can rotate the support shaft and the feed blade. For example, a drive motor (such as an invert type or a motor with a transmission) can be employed. Further, due to the configuration of the apparatus, the first and second driving means are not provided, and the driving force of the existing equipment can be used for the rotation of the support shaft and the feed blade.

That is, according to the present invention, there is provided a granular surface polishing apparatus for polishing a surface of a granular material by bringing it into contact with a rotating polishing grindstone. A polishing grindstone attached to the support shaft and having a substantially cylindrical shape as a whole, a casing accommodating the polishing grindstone and being concentric with the polishing grindstone with respect to the device fixing structure, and a casing in a longitudinal direction of the casing. A charging port provided at one end side, into which the granular material to be polished is introduced, a discharge port portion provided at the other end in the longitudinal direction of the caging, and discharging the polished granular material; And a feed blade for rotating the supplied granular material toward the discharge port portion while rotating around the polishing grindstone, and providing a surface polishing apparatus for the granular material. Door can be.

The feed blades need only be rotatable around the grinding wheel. For example, the feed blades may be rotatably supported with respect to the device fixing structure, but the support structure tends to be complicated. Therefore,
It is preferable that the feed blade is fixed to the inner surface of the casing, and the casing is rotatably supported with respect to the device fixing structure.

That is, the casing is rotatably supported concentrically with the grinding wheel with respect to the apparatus fixing structure, the feed blades are fixed to the inner surface of the casing, and the granular material charged with the rotation of the casing is discharged. It is better to be transported to. In this case, the feed blade is rotated by the second driving means via the casing. Further, the casing may be supported by bearings, but the support structure tends to be complicated. Therefore, as shown in the following embodiment, a method in which the outer peripheral surface of the casing is rotatably received and supported by four receiving rollers is preferable.

The shape and form of the feed blades are not particularly limited as long as the particles can be transferred by rotation around the grinding wheel.
For example, a spiral feed blade may be employed, but considering the provision of a scraping plate described later, a plurality of blade main bodies which stand substantially perpendicularly to the inner circumferential surface of the casing and are inclined in the circumferential direction. It is good to be comprised including. The number of feed blades is not particularly limited, and four feed blades can be provided as shown in the following embodiment.

The shape of the casing is not particularly limited as long as the casing can accommodate the polishing grindstone. However, when the feed blade is fixed to the casing, it is necessary to allow relative rotation with respect to the grinding wheel. Therefore, in order to ensure smooth rotation of the casing, the inner surface of the casing may have a circular cross section, preferably a cylindrical shape.

Further, in the method in which a granular material is brought into contact with a polishing grindstone and the surface thereof is polished, if the granular material is scraped up and collides with the polishing grindstone, a massive granular material can be crushed. Therefore, a scraping plate provided in the casing, which rotates around the grinding wheel, scrapes up the transported particulate matter and drops it toward the grinding wheel, and third driving means for rotating the scraping plate. Is preferably provided, and the massive granular material is crushed by colliding with a polishing grindstone.

The third drive means may be of any type and structure as long as the scraping plate can be rotated. For example, a drive motor (an invert type, a motor with a transmission, etc.) can be used. In addition, due to the configuration of the apparatus, the driving force of existing equipment can be used for rotating the scraping plate without providing the third driving means. That is, further provided is a raking plate that is provided in the casing and lifts up the transferred granular material and drops it toward the grinding wheel while rotating around the grinding wheel, and collides the massive granular material with the grinding wheel. It can also be made to crush.

The scraping plate only needs to be rotatable around the polishing grindstone. For example, the scraping plate may be rotatably supported on the device fixing structure portion, but the supporting structure tends to be complicated. Therefore, the scraping plate is fixed to the inner surface of the casing, and the casing is rotatably supported concentrically with the grinding wheel with respect to the device fixing structure, and the transferred granular material is scraped up with the rotation of the casing and polished. It is better to drop it toward the whetstone. In this case, the scraping plate is rotated by the third driving means via the casing. However, since the functions of the second and third driving means are common, it is preferable to use both the second and third driving means. Good.

The support shaft and the casing can be provided to be inclined with respect to the horizontal direction. In this case, however, uneven wear tends to occur on a support such as a bearing. Thus, the support shaft and the casing may be arranged to extend substantially horizontally.

One of the features of the present invention is that a mechanical feed mechanism is provided instead of a negative pressure. Therefore, when air is sent in the countercurrent direction to the transferred granular material, fine powder generated by surface polishing can be separated from the granular material, and at the same time, the granular material in the casing can be cooled.

In view of this, an air inlet port for sending external air through the casing toward the inlet port side is provided on the discharge port side, and the fine powder whose surface has been polished is separated from the particulate matter by sending the external air. Preferably, the granular material in the caging is cooled. In this way, when the granular material in the casing is cooled by external air, for example, when regenerating high-temperature molding sand immediately after casting, the molding sand is regenerated and is not discharged at a high temperature, and is cooled by an external cooler. In this case, even if a small external cooler is used, it can be cooled to a predetermined temperature, for example, room temperature, in a short time.

As described above, since fine powder can be separated from the particulate matter by blowing in external air, a connection port of a dust collector is provided on the charging port side, and the fine powder separated by blowing external air is supplied to the charging port. It is good to collect dust on the part side.

In the case of polishing the surface of a granular material that does not cause a temperature problem, a connection port of a dust collector is provided on the input port side and the discharge port side, and fine powder generated by the surface polishing is supplied to the input port side. Dust can also be collected at the discharge port side.

[0028]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to specific examples shown in the drawings. 1 to 7 show a preferred embodiment of a granular material polishing apparatus according to the present invention.
In the figure, support legs 11, 11 are erected on both sides in the width direction of the upper stage of the device frame (device fixing structure portion) 10,
A support shaft 12 extending in a horizontal direction is rotatably supported by the support legs 11, 11 by bearings 13, 13.

Each of the center holes of a plurality of disk-shaped grinding wheels 14 is fitted on the support shaft 12, and the plurality of grinding wheels 14 are arranged in a columnar shape as a whole. . The polishing grindstone 14 is manufactured using hard abrasive grains such as carborundum, alumina, ceramics, porazon, diamond, and tungsten carbide.

On both sides of the polishing grindstones 14... Of the support shaft 12, holding plates 15, 15 are externally fitted. The holding plate 15 is pressed against the polishing grindstone 14 by a sleeve 16 provided on the support shaft 12. The sleeve 16 is fixed by a balance adjusting plate 17 screwed to the support shaft 12.

A pulley 18 is provided at one end of the support shaft 12.
Is fixed, and a drive motor (first drive means) 19 is mounted in the middle stage of the device frame 10.
A pulley 20 is fixed to the rotation shaft of the drive motor 19.
An endless driving force transmission belt 21 is stretched between the pulley 20 of the support shaft 12 and the pulley 18 of the support shaft 12 so that the grinding wheels 14 are rotated.

A casing 22 having a substantially cylindrical shape is disposed on the upper stage of the apparatus frame 10 so as to be concentric with the support shaft 12 and house the polishing grindstones 14... On the outer peripheral surface of the casing 22. The rings 23, 23 are fixed at a predetermined interval from each other in the axial direction.

On the other hand, four support brackets 24 are fixed at the upper part of the apparatus frame 10 at intervals in the axial direction and at intervals in the width direction, and are juxtaposed in the axial direction. Support shafts 25, 25 are rotatably supported by the pair of support brackets 24, respectively, and receiving rollers 26, 26 are fixed to both ends of the support shaft 25, and the casings are fixed by the four receiving rollers 26,. The casing 22 is rotatable by receiving the annular rings 23, 23.

The two support shafts 2 arranged side by side in the width direction
A sprocket 27 is fixed to one of 5, 5 and 25, and a drive motor (second drive means and third drive means) 28 is mounted in the middle stage of the apparatus frame 10, and a rotating shaft of the drive motor 28 The sprocket 29 of the drive motor 28 and the sprocket 27 of the support shaft 25 are connected by a driving force transmission chain (not shown), and the rotation of the drive motor 28 While being transmitted to the both-end ring receivers 26 and 26 and rotating, the both-end ring receiver 2 of the other support shaft 25 is rotated.
6 and 26 are driven to rotate, whereby the casing 22 rotates around the grinding wheels 14.

Four feed blades 30 are fixed to the inner peripheral surface of the casing 22 at an interval of 90 ° from each other in the circumferential direction. As shown in FIG. 5, the feed blade 30 is configured by fixing a plurality of blade main bodies 32 to a mounting plate 31. The mounting plate 31 is shaped like a side arc so as to match the inner peripheral surface of the casing 22. The casing 22 is disposed so as to extend in the central axis direction of the casing 22.
Is fixed to the inner peripheral surface of the base member by screws or bolts.

The blade body 32 stands upright with respect to the mounting plate 31 and is inclined at a predetermined angle with respect to the circumferential direction of the casing 22. At the end of the mounting plate 31, a return blade 33 stands upright with respect to the mounting plate 31, and is inclined at an angle opposite to that of the blade main body 32 with respect to the circumferential direction of the casing 22.

On the inner peripheral surface of the casing 22, a raking plate 34 is provided between the adjacent feed blades 30, 30. As shown in FIG. 6, the scraping plate 34 is constituted by fixing a plurality of scraping plate bodies 36 to a flat mounting plate 35, and the plurality of scraping plate bodies 36 are mounted. Board 3
5 and is inclined at a predetermined angle with respect to the circumferential direction of the casing 22.
Are formed at predetermined intervals from each other.

On the other hand, a mounting base 38 is provided on the inner peripheral surface of the casing 22 so as to extend in the central axis direction of the casing 22. The base of the mounting base 38 is the casing 2
2 has a substantially arcuate side so that it can match the inner peripheral surface of 2,
The casing 22 is fixed to the inner peripheral surface by screws or bolts. A vertical wall portion is provided upright at the base, and the bolt is inserted through the elongated hole 37 of the mounting plate 35 of the scraping plate 34 at the base. By adjusting the position of the bolt in the elongated hole 37, the distance between the polishing grindstone 14 and the like can be set.

The inspection hole 3 is provided on the side surface of the casing 22.
9 are formed at 90 ° angular intervals in the circumferential direction,
A lid 40 for closing the inspection hole 39 is attached by a screw or a bolt so that the condition of the feed blade 30 and the scraping plate 34, and the condition of wear of the polishing grindstones 14 can be inspected. .

In the upper part of the device frame 10, the casing 2
A chute (input port) 41 is fixed to one end of the casing 2, while the casing 2 is attached to the chute 41 of the casing 22.
A plurality of feeding blades 43 for feeding the granular material thrown in from the chute 41 toward the casing 22 side are fixed to the frusto-conical portion 42 that constitutes a part of 2. It is fixed at a predetermined angular interval in the circumferential direction.

In the upper part of the apparatus frame 10, a cylindrical outlet 44 is provided on the opposite side of the chute 41 from the casing 22.
It is fixed in communication with the inside, and a cylindrical air inlet port 44 is connected and connected above the outlet port 44. On the other hand, the chute 4 is
A cylindrical connection port 46 of a dust collector (not shown) is provided in communication with the inside of the casing 22 in addition to 1.

Since a control device for the drive motors 19 and 28 is not directly related to the present invention, a description thereof is omitted, but a known device can be adopted. In order to prevent scattering of dust, the casing 22 and the discharge port 4
Preferably, a sealing material is provided between the casing 4 and the air inlet 45, and between the casing 22 and the chute 41 and the connection port 46 of the dust collector.

When the casting sand W after casting is regenerated, the drive motors 19 and 28 are operated to rotate the polishing grindstones 14... And the casing 22 in mutually opposite directions (see arrows in FIGS. 3 and 7). Then, the dust collector is operated, and at the same time, external air is introduced into the air inlet 44.

When the preparation is completed, the casting sand W to be regenerated is introduced from the chute 41. Then, the injected molding sand W is sent to the casing 22 by the feeding blades 43.
And between the polishing whetstones 14... At this time, the feed blades 30.
Are rotating around the polishing grindstones 14..., And the fed casting sand W is transported in the casing 22 toward the discharge port 44 side by the feed blades 30. reference).

Also, as the casing 22 rotates, the scraping plates 34... Also rotate around the polishing grindstones 14. 34 ... one after another, the polishing whetstone 14
Are dropped from directly above and collide with the polishing grindstones 14 (see FIG. 7).

The casting sand W thus introduced is stirred while being transferred into the casing 22 toward the discharge port 44 side. Among the casting sand W, a lump of the casting sand W is crushed by the impact of collision, and a granular casting sand W is formed. The sand W and the crushed casting sand W are uniformly contacted with the entire surface of the polishing grindstones 14.

The casting sand W is discharged from the outlet 44 of the case sink 22.
Is returned in the opposite direction by the return blades 33... On the end side of the feed blades 30..., And the agitation of the molding sand W is promoted. 44
(See arrow B in FIG. 2).

At this time, on the chute 41 side, the inside of the casing 22 is collected by a dust collector (see arrow D in FIG. 2).
Further, external air is supplied from the air supply port 45, and the external air moves in the casing 22 in a counter-current direction with respect to the transfer direction of the molding sand W (arrow C in FIG. 2).
), The hot molding sand W is cooled. Therefore, the recycled casting sand W discharged from the discharge port 44 is sufficiently cooled, and can be used immediately for the next sand mold.

At the same time, the fine powder generated by the polishing is separated from the molding sand W by the external air and collected by the dust collector, so that the quality of the recycled molding sand W is high. According to the experiments of the present inventors, it is confirmed that 90% or more of the generated fine powder can be separated.

Further, the injected molding sand W is supplied to the feed blade 3
0 ... mechanically, so that the feed blade 3
The residence time of the foundry sand W in the casing 22 can be freely controlled by controlling the rotation speed of 0.
It can always be optimally regenerated according to the state of the casting sand W.

[Brief description of the drawings]

FIG. 1 is a schematic overall view showing a preferred embodiment of an apparatus for polishing a surface of a granular material according to the present invention.

FIG. 2 is a side cross-sectional configuration diagram illustrating a main part of the embodiment.

FIG. 3 is a front sectional configuration diagram showing a main part of the embodiment.

FIG. 4 is a diagram showing a relationship between a feed blade 30 and a scraping plate 34 in the embodiment.

FIG. 5 is a front view of the feed blade 30 in the embodiment.
It is a figure which shows (a) and side (b).

FIG. 6 is a view showing a front surface (a) and side surfaces (b) of four scraping plates 34 in the embodiment.

FIG. 7 is a diagram schematically showing crushing and polishing behavior in the embodiment.

FIG. 8 is a schematic view showing a polishing behavior in a conventional surface polishing apparatus from the front.

FIG. 9 is a schematic view showing a polishing behavior in a conventional surface polishing apparatus from a side.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Device frame (device fixed structure part) 12 Support shaft 14 Polishing grindstone 19 Drive motor (1st drive means) 22 Casing 28 Drive motor (2nd, 3rd drive means) 30 Sending blade 31 Mounting plate 32 Blade main body 34 Raising plate 41 Chute (input port) 44 Discharge port 45 Air inlet 46 Connection port of dust collector W Foundry sand (granular material)

Claims (13)

[Claims] An apparatus for polishing a surface of a granular material, which is brought into contact with a rotating grinding wheel to grind the surface of the granular material, comprising: a support shaft rotatably supported on an apparatus fixing structure; A first driving means for causing the polishing wheel to be attached to the support shaft and having a substantially cylindrical shape as a whole; and a casing accommodating the polishing wheel with respect to an apparatus fixing structure portion and containing the polishing wheel. A charging port provided at one end in the longitudinal direction of the casing and into which the granular material to be polished is provided; and a discharge port provided at the other end in the longitudinal direction of the caging and discharging the polished granular material. An outlet portion, a feed blade provided in the casing, for transferring the supplied granular material toward the discharge port portion while rotating around the polishing wheel, and rotating the feed blade. Surface polishing apparatus of granules, characterized by comprising a second driving means. 2. A granular surface polishing apparatus for polishing a surface of a granular material by bringing it into contact with a rotating polishing grindstone, comprising: a support shaft rotatably supported on an apparatus fixing structure portion; A grinding wheel having a substantially columnar shape as a whole, a casing which is concentrically supported by the grinding wheel with respect to an apparatus fixing structure portion and accommodates the grinding wheel, and which is provided at one longitudinal end of the casing. A charging port into which the granular material to be polished is charged; a discharge port provided at the other end in the longitudinal direction of the caging, and discharging the polished granular material; An apparatus for polishing a surface of a granular material, comprising: a feed vane for rotating an introduced granular material toward the discharge port while rotating around a grindstone. 3. The apparatus according to claim 1, wherein said casing is rotatably supported concentrically with said grinding wheel with respect to an apparatus fixing structure portion, said feed blade is fixed to an inner surface of said casing, and said granular material is supplied with rotation of said casing. The apparatus for polishing a surface of a granular material according to claim 1 or 2, wherein the material is transferred toward the discharge port. 4. The apparatus for polishing a surface of a granular material according to claim 3, wherein said casing is rotated by said second driving means. 5. The surface of the granular material according to claim 3, wherein the feed blade includes a plurality of blade bodies that stand substantially perpendicular to the inner peripheral surface of the casing and that are inclined in the circumferential direction. Polishing equipment. 6. A scraping plate which is provided in the casing, and which rotates around the polishing grindstone, scrapes up the transferred particulate matter, and drops it toward the polishing grindstone. The apparatus for polishing a surface of a granular material according to claim 1, further comprising a third driving means for rotating, wherein the granular material is crushed by colliding with the polishing grindstone. 7. A scraping plate provided in the casing, wherein the scraping plate is configured to scoop up the transferred granular material and drop it toward the polishing grindstone while rotating around the polishing grindstone. 3. The apparatus for polishing a surface of a granular material according to claim 2, wherein the material is crushed by colliding the material with the grinding wheel. 8. The apparatus according to claim 1, wherein the casing is rotatably supported concentrically with the grinding wheel with respect to an apparatus fixing structure, the scraping plate is fixed to an inner surface of the casing, and the transferred granular material is fixed to the casing. 7. The method according to claim 6, wherein the liquid is scraped up with the rotation and dropped toward the grinding wheel.
Or a device for polishing a surface of a granular material according to 7. 9. The apparatus for polishing a surface of a granular material according to claim 8, wherein said casing is rotated by said third driving means. 10. The apparatus for polishing a surface of a granular material according to claim 1, wherein the support shaft and the casing extend substantially horizontally. 11. An air inlet port for sending external air through the casing toward the inlet port side is provided on the discharge port side, and the fine powder whose surface has been polished by the supply of the external air is provided. 11. The apparatus for polishing a surface of a granular material according to claim 1, wherein the granular material is separated from the granular material, and the granular material in the caging is cooled. 12. A connection port of a dust collector is provided on the input port side, and the fine powder separated by blowing in the external air is collected on the input port side. Polishing equipment for granular materials. 13. A connection port of a dust collector is provided at the input port side and the discharge port side so that fine powder generated by surface polishing is collected at the input port side and the discharge port side. An apparatus for polishing a surface of a granular material according to any one of claims 1 to 10.