WO2000045994A1

WO2000045994A1 - Grinding beads and beads production method and device therefor

Info

Publication number: WO2000045994A1
Application number: PCT/JP2000/000516
Authority: WO
Inventors: Naoyoshi Tomioka
Original assignee: Bridgestone Corporation
Priority date: 1999-02-01
Filing date: 2000-01-31
Publication date: 2000-08-10
Also published as: AU2323400A; JP3626098B2

Abstract

Grinding or separating beads which are easy to adjust in grain size, consist of amorphous polyhedral slender elements suitable for instantaneous separation, and have classification-based homogeneous grain sizes. The beads production device comprising crusher units (11) for roughly crushing platy moldings of thermosetting resin into a dice- or pellet-form and a roll-type crushing unit (16). The crushing unit (16) comprises multi-stage crushing rolls (31 to 33) in which irregularities (36) formed on the surfaces of each pair of facing rolls are phase-deviated at 1/2 of a pitch and which crushes coarsely-crushed thermosetting-resin pieces into specified sizes. Classifying devices (20, 21, 22) disposed downstream the crushing unit (16) classify the resultant pieces to provide beads which are homogenized according to classification and which consist of amorphous polyhedral slender elements having sharp ridges.

Description

Details

Grinding beads and method and apparatus for producing beads

Technical field

The present invention is applicable to the grinding of various metal and synthetic resin parts, the peeling of coating films, rust, burrs, adhesive layers, seals, etc., the cleaning and polishing of various tools, jigs, polishing, road marking signs or concrete. The present invention relates to beads used for instantaneous peeling of wall stains and the like, and further relates to a method and an apparatus for producing the beads.

Background art

Fine beads of thermosetting resin are sprayed by air pressure to grind the surface of various metals, synthetic resins-wood, glass, and other materials, and paint films, rust, burrs, adhesive layers, seals, and waxes. There is known a method of instantaneously peeling off road markings, dirt, graffiti, etc. on road surface signs, concrete wall surfaces or tiles such as white roads. For example, in Japanese Patent Application Laid-Open No. HEI 4-111776, a molded product obtained by adding a filler such as a reinforcing material or a filler, a coloring agent, or the like to a thermosetting resin, kneading the mixture, and heat-curing to cure the molded product is used. It discloses that the powder is crushed into a mesh of 5 to 100 to provide an abrasive for a base treatment of a coating, and this is sprayed onto a coating surface of a metal product to peel off the coating. In Japanese Patent Application Laid-Open No. 61-152,370, a thermosetting resin is cured and pulverized, treated with a titanium coupling agent, and dispersed in the thermosetting resin before curing. It discloses that the material is ground into an abrasive. Also, in Japanese Patent Application Laid-Open No. H8-733813, in order to eliminate the electrification on the object to be cleaned by the resin particles for cleaning, the electric potential elimination of the ether 'nitrile compound is applied to the resin particles for cleaning. It discloses abrasive materials used for blast grinding and barrel processing. Further, in Japanese Patent Application Laid-Open No. 8-90420, heat treatment of a pulverized product after coarse pulverization or fine pulverization of a thermosetting resin is carried out, whereby the hardness of the resin abrasive particles is made uniform, and the impact fracture strength is improved. Abrasives with improved water content and uniform moisture content are disclosed.

Thermosetting resins have long been manufactured and sold as fine powder dried resins and resins for granular molded products. Melamine resin and Urea resin as raw materials (raw materials) It is standardized as a general-purpose product with specific gravity, hardness, etc. (JIS K 6917, K 6916), with 60 to 70% of melamin powder and 2 to 4 monograms per melamin monolayer. (30% to 40% aqueous solution of formaldehyde), 0.1% catalyst, and 40% to 30% filler such as pulp Molded melamine resin has a hard surface and no filling It is also known that the specific gravity in the case of lumber: 1.48 rises to some extent.

Conventional release materials, abrasive materials or abrasive materials are obtained by cutting thermosetting resin molded products with a circular or polygonal cross section into fine pieces in the shape of a cylinder or a square tube. However, when sprayed onto a workpiece, the peeling ability was insufficient, and it took time to completely peel off, and there was a limit to the particle size adjustment.

Therefore, a first object of the present invention is to provide a pulverized thermosetting resin molded product, in which each particle is formed into an irregularly shaped polyhedral fine substance substantially surrounded by a sharp ridgeline, and a particle size at a classification stage. An object is to provide beads that are almost homogenized within a certain range. Further, a second object of the present invention is to roughly pulverize a plate-like molded product of a thermosetting resin, and then pulverize between rolls having irregularities with a phase difference of 1/2 pitch formed on the roll surface. Accordingly, it is an object of the present invention to provide a method and an apparatus for producing beads for grinding and peeling an irregular polyhedron having a sharp ridge line. Disclosure of the invention

In order to achieve the above object, the beads according to the present invention are characterized by having the following configuration.

That is, the present invention relates to a crushed product of a thermosetting resin molded product having a particle size of 1000 to about 5.0 m, wherein each particle is substantially irregular and fine polyhedron surrounded by sharp ridges. This is a grinding / peeling bead whose grain size at each classification stage is almost homogenized within a certain range. The thermosetting resin is filled with pulp and glass fiber crushed pieces, and further contains carbon, artificial graphite or metal fibers. Specifically, 30 to 40% of a valve and 0.1 to 0.5% of a glass fiber cloth piece are mixed in the thermosetting resin material after condensation, and static electricity is generated after the resin is aged and dried. Compounded with carbon powder or artificial graphite with electrical conductivity of 0.2 to 0.3 for suppression and electrification suppression, and 0.1 to 0.5% of metal powder or metal fiber to increase specific gravity to 1.8 or more I do.

Two

Corrected form (Rule 91) In order to produce the beads, the present invention uses a thermosetting resin plate-like molded product. The obtained product is crushed (roughly divided) into a die shape or a pellet shape, and then the irregularities on the roll surface facing the same are obtained. Is crushed by a multi-stage crushing roll arranged with a 1/2 pitch phase shift to form irregular polyhedral fines (beads) with sharp ridges. In the present invention, as the thermosetting resin, melamine resin (melamine-formaldehyde resin), urine resin (urea-formaldehyde resin), phenol resin, and unsaturated resin Polyester, acrylic, guanamine, epoxy or polyurethane alone, or with hardness and specific gravity ■ Several kinds of thermosetting resins with different viscosities can be mixed. These materials are non-polluting even when used, have high electrical insulation resistance for the purpose of expanding the range of use, are resistant to alkaline acids, are relatively high in heat resistance, Non-flammable (flammable, ignitable), non-toxic (styrene, ester, etc.), and relatively powdery due to the impact of nozzle injection during recycling. It is selected from the viewpoints of difficult-to-viscous substances. Preferably, a force for crushing a resin plate-like molded product obtained by mixing a urea resin and / or a phenol resin with a melamine resin, or a melamine resin, a urea resin, or a phenol resin The different types of resin plates are coarsely crushed and mixed, and then ground to form irregular polyhedral fines.

Grinding and peeling effects are exhibited by the hammer action of spraying beads with sharp polygonal faces, but the hammer action of beads of one or different kinds of the same hardness can damage the target substrate and the beads themselves. Cause a crusher ". Therefore, the present inventor repeatedly performed grinding or peeling experiments using beads in which several kinds of beads of different hardnesses were mixed, and found that a group of beads having a lower hardness served as a cushioning material and the target substrate was formed. It was confirmed that the beads were not damaged (buffering effect), could prevent the beads from crushing, and the number of recycles was further increased.

As an apparatus for manufacturing beads, a plate-shaped molded product of thermosetting resin is an irregular shape of approximately 2 to 4 mm square (maximum thickness 5 mm, flat object with approximately 7 sides). A crusher section that crushes into a shape like a pellet, a sorting section that removes metal and foreign matter in crushed material crushed by a part of the crusher, and a 1Z2 pitch Coarse with crushing rolls for crushing the crushed material selected at the sorting unit with irregularities formed with a phase shift Similar to the crushing part of the crushing part and the crushing part, there is also a phase shift of 1 Z 2 pitch on the roll surface.The crushed material obtained in the crushing part with irregularities formed has a particle size of 100 to 500 μm. It comprises: a crushing section having a multi-stage crushing roll pair for processing into amorphous fine polyhedral beads having a sharp ridge at πι; and a classification device arranged downstream of the crushing section.

The crushing unit equipped with the above-mentioned multi-stage crushing roll pair has a particle size adjustment mechanism that changes and adjusts the bead particle size by setting the unevenness pitch of the crushing rolls and the clearness between the opposing rolls to be optimal. I have it.

Furthermore, this bead manufacturing apparatus arranges a classifier such as an air classifier, an electric power classifier, and a vibrating sieving machine downstream of the pulverizing section to classify the beads, weigh and classify the classified beads. A fixed amount of bead packaging for peeling. In addition, a circulation line is provided to return the fines above or below the mesh in each classifying step upstream of the sorting section or upstream of the crushing section, and the fine particles generated in each step from the crusher section to the classifying apparatus are provided. Equipped with a powder transport conveyor or duct that guides dust containing particles to the dust treatment equipment.

As the classifying device, a vibrating sieve having several stages of sieves with successively finer stitches and deriving shoots from sieves on each sieve is suitable. The first-stage mesh-up is sent to the crusher and crushed again, and the lower-most mesh under is discarded as dust. Sent to a packing machine or 20kg bagging machine, weighed, packed in a bag, and sequentially carried out i.

The beads obtained by the present invention can be ground without damaging various metals, synthetic resins, wood, glass and other products, or painted films, adhesive layers, seals, waxes, concrete walls or tiles. Used for instantaneous peeling of stains and graffiti. In addition to the above-mentioned product materials, the products to be processed (workpieces) include coating and peeling of equipment and parts, rust removal, reproduction of defective coating, electrical components, molded products, molds, cleaning of jigs, etc. It is used for polishing, polishing, road marking (white line, etc.), and peeling off of adhering materials or seals on buildings. The advantages of using the above bead are that the speed of grinding and peeling has been shortened, making it possible to shorten the working time, not to damage the work, to reduce costs, and to reduce dust and dust. Low noise generation.

Further, the beads of the present invention are excellent in antistatic properties, economical efficiency and grinding / peeling properties, and are suitable for recyclability, as described below. 1. First, in the present invention, in the production process of this general-purpose raw material material (plate-like resin molded product having a thickness of 2 to 5 mm), a specific filler is blended to form a peeling bead. The aim is to improve the effect of removing particles.

a. Carbon powder (carbon black) is blended as filler (trace%).

Purpose: To suppress the generation of static electricity during blasting by blending highly conductive materials. b. Mix metal powder and metal fiber (trace amount).

Purpose: To increase the specific gravity to 1.8 to 2.0, while the specific gravity of general-purpose products is 1.30 to 1.48. This is effective for polishing iron products and removing road debris without worrying about damaging the material surface of the blast target.

c. Pulp 'Mix cellulose fiber or glass fiber cloth pieces.

Purpose: To increase hardness and mechanical strength.

2. Adjust the impact strength of the blast by mixing the melamine resin and the urine resin.

Molding of resin plate: The above-mentioned raw material is filled in a mold, and molded (Zmra for 60 to 180 seconds) under pressure (150 to 200 kg / cm ² ) and heating (130 to 165 ° C). The molding time varies depending on the thickness of the molded product, but a high hardness can be obtained by increasing the molding time at a low temperature.

3. Classification standards for grinding and peeling beads for each application [MG (MA GIC-G EM) series number named by the applicant] are as follows.

a.—For general metal (hard material)

MG — 0 150 0 μm Up

MG-12 0 Mesh under or 8 4 0 μm up

MG—32 0 to 30 mesh (840 to 500 μιη)

b. Aluminum (soft material)

G-530-500 mesh (500-300 μm)

MG—750-70 mesh (300-212 μm)

c High-end products such as resin products, electronic components or molded products

MG-107--; 140 mesh (2 120 m)

MG — 14 16 μm or less.

4. Recyclability During the blasting operation, the beads are crushed and the particle size is reduced by spraying on the target object, and the sharp ridges are rounded. I do. Even if the bead diameter becomes smaller, the polyhedral shape of each particle and the grinding-peeling efficiency do not change. It can be reused several to several tens of times depending on the hardness of the target product, the hardness of the beads, specific gravity, air pressure, spray angle, spray distance, and other factors. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a flowchart of the method for producing a peeling bead of the present invention.

FIG. 2 is a layout diagram showing an outline of a bead manufacturing apparatus for carrying out the present invention.

FIG. 3 is a perspective view of the crushing unit of FIG.

FIG. 4 is an enlarged perspective view of the grinding roll pair in FIG.

FIG. 5 is an enlarged cross-sectional view of the uneven teeth of the crushing roll.

FIG. 6 is an enlarged sectional view showing the deformation of the uneven teeth of the crushing roll.

FIG. 7 is a layout diagram showing details of each part from pulverization to packaging in FIG.

FIG. 8 is an enlarged plan view illustrating a group of peeling beads. BEST MODE FOR CARRYING OUT THE INVENTION

Figure 1 shows the bead production flow.

Melamine powder 1a, formalin 1b, and alcohol or acid catalyst 1c are charged into reaction tank 2 and polymerized and condensed, and then transferred to mixing tank 3 to be used as a filler. % Kneading of the pulp 3a and 0.1 to 0.5% of the glass fiber cloth strip 3b. After passing through the aging tank 4 and the drier 5, in the ball mill 6, carbon powder (a carbon black having a conductivity of 0.3%) for suppressing static electricity generation during blasting and a carbon powder for increasing the specific gravity are used. 0.1 to 0.5% of metal fiber 6a is blended, and a coloring material is blended if necessary.

The foreign matter is removed at the sieving section 7 to obtain a molding material (melamine resin) 8. Add molding material (urea resin) 8a obtained by almost the same procedure as above, knead 8c, pressurize and heat and mold to form a resin with a thickness of 2 to 5 mm with different hardness and specific gravity Get 10

The raw material is formed into a plate-like material, and the process from crushing (crushing) to crushing and packaging is not only performed consistently, but it is divided into several processes.

6

Made paper (Rule 91) To manufacture finished product beads.

Next, a crusher 11 for crushing each of the above-mentioned plates 10 into a die or a pellet of about 2 to 4 mm square, a pre-mixing section 12 for mixing crushed materials, and a magnetic separation for foreign substances. Separation section 14, crushing 15, crushing with several crushing rolls 16, sieving 18, weighing 23, packing 24, and then unloaded 25.

[Bead production equipment]

FIG. 2 is a front view schematically showing a bead manufacturing apparatus, FIG. 3 is an enlarged perspective view of a crushing unit in FIG. 2, and FIG. 4 is an enlarged cross-sectional view of a crushing roll in FIG.

As shown in Fig. 2, several types of resin plates 10 (thickness: 3 to 5 mm, 300 x 500 mm) of thermosetting resin molding materials with different hardness and material are applied to the crusher section 1. It is crushed (roughly divided) into an irregular die or pellet of approximately 2 to 4 mm square (maximum thickness 5 mm X l side 7 mm flat) with 1 and put into the mixing section 12 . In FIG. 2, six types of resin plates 10 of A, B, C, D, E, and F are illustrated, but these are not limited to the same material, and two or more types of materials may be used. Good. That is, the resin plate 10 is selected from molding materials such as melamine resin, urea resin, phenol resin, unsaturated polyester, acrylate, guanamine, epoxy or polyurethane. 60% to 80% of melamine mixed with 40% to 20% of urea, one resin is made of melamine, urea, and funinol resin. It may be a mixture of two or more types of mixed materials, such as mixing. The melamine resin plate and the urea resin plate or the phenol resin plate may be crushed by a crusher, and then mixed. Unlike conventional hammer mills, disk crushers, cone crushers, oscillators, etc., the crusher 11 has several movable blades (closed flat cutters with serrated blades) attached to the rotor. A type that crushes between the fixed blade and the fixed blade by rotation of the rotor (not shown) is used. Hammer type crushers are not effective because only a lot of cracks appear in the crushed product or dust is generated during crushing. The resin plate 1 ◦ is not limited to sheet-like material, but should be used in advance to crush crushed thermosetting resin materials, such as sprues, runners and defective moldings generated during molding of resin materials. As a result, if it is possible to stably supply an irregular shaped material of approximately 2 mm square of a predetermined quality as a material, the crusher unit 11 in Fig. 2 is omitted and the mixture is directly introduced into the mixing unit 12. You may. [Crushing and sieving of crushed material]

An automatic feeder 13 and a rectifying feeder 13a are provided below the mixing section 12. The crushed material flowing down by the rectifying feeder 13a is rectified into a layer having a substantially uniform thickness, and sent to the metal 厲 'sorter 14 for removing foreign matter. Below the sorting unit 14, a crushing unit (with a pair of crushing rolls and a static eliminator) 15 and a crushing unit (multi-stage crushing roller pair and a static eliminator) 16 are provided, and further switched It is connected to a screening section 18 through a valve 17. The sieving section 18 is composed of an air classifier 21 for classifying fine particles and a power classifier 22 for classifying large-diameter particles from fine particles. The classified granules (beads for peeling) are packaged into peeling beads of a predetermined volume by the bagging machine 23 with an automatic weighing machine, which corresponds to the packaging shipping department, and the automatic bag mouth sewing machine 23, and the transporter 2 It is carried out of the site using 5 mag.

The fines on the mesh of the electric power classifier 22 are introduced into the circulation pipe 26a and returned to the rectifier feeder 13a with hopper upstream of the sorting section 14a. The fine particles on the mesh of 21 are introduced into the circulation pipe 26 b and returned upstream of the crushing section 15. The dust generated at each stage is sent to an upper dust treatment device (separation device) 28 through a duct 27 as shown by the dotted line in Fig. 2, and the dust having a predetermined particle size is passed to the mixer 12. On the other hand, the fine powder having a predetermined particle size or less is sent to the dust collector 29 for disposal.

[Configuration of crushing roll]

In FIG. 2, 15a and 15a are crushing rolls, 15b is a honno, and 15c is a rectifying feeder for rectifying the crushed material flowing down from the hobber into a layer having a substantially uniform thickness. The crushing roll 15a has lateral grooves 35 extending in the generatrix direction at regular intervals on the circumference of the roll surface, as described later for the crushing roll, and has many irregularities 36 on the roll surface. Let me.

The crushed pieces of 2 to 4 mm square die or pellets at the crusher section 11 are crushed into approximately 2 mm square by rotating the crushing rolls 15a and 15a. I do.

[Configuration of crushing unit]

FIG. 3 is an enlarged perspective view of the crushing section 16 in the bead manufacturing apparatus, and FIG. 4 is a perspective view of a crushing roll pair. A pair of pulverizing rolls 31, 31, 32, 32, 33, and 33 are laid on the frame 30 in three vertical stages. Each roll surface has several (four) lateral grooves 35 extending in the generatrix direction at regular intervals on the circumference, and a number of mountain-shaped irregularities 36 on the roll surface. (Fig. 5). Ni will Yo described later, the mouth one by operating the Lee Nde' click scan gauge dial 3 7. Le gap 0.1 to adjust to 0. 2 _m m (Figure 4). Figure 6 shows a roll with a number of angular irregularities 36a formed on the roll surface.

A scraper 38 is placed close to each roll.

In Fig. 3, 40 is a motor with a speed reducer, 41, 42, and 43 are portal shafts of each stage, and 44 is a chain hung between the motor and the first stage roll shaft sprocket. 45 is a chain hung between the sprockets of the roll rollers facing each other. A synchronous rotation gear (not shown) is interposed between the opposing first-stage roll shafts.

[Size of grinding roll]

In the crushing (processing) unit 16, the roll pitch is gradually increased while the roll pitch is gradually reduced from the first stage to the third stage. For example, the diameter of each roll is 150 mra, and the uneven pitch and rotation speed of each stage are as follows.

First stage: pitch 2.0 mm, V ₁ = 500 to 52 rpm (5 17 rpm).

Second stage: pitch 1.2 mm, V ₂ = V i X 1.2 to 1.3 (632 rpm).

Third stage: pitch 0.6 mm, V ₃ = around V i X 1.5 (772 rpm).

The rolls of the crushing section 15 also have the same irregularities.

In the manufacturing process, homogenization is performed using several stages of crushing rolls in the crushing and crushing sections. In order to homogenize the bead shape, the roll shape (concavo-convex pitch) and the clearance between rolls were emphasized, and as a result, the bead particle size (size) was easily changed. Before operation, it is necessary to correctly set (match) the positions where the peaks and valleys 36, 36 facing each other of the rolls face each other. For this reason, an adjustment bolt (not shown) is provided on the bearing portion of one of the rolls (for example, the roll on the rear side of each stage in FIG. 2) which is mounted so as to be movable in the axial direction and extends in the axial direction of the roll. The end of the top is abutted against the side wall of the frame to form the alignment mechanism. Adjusting the effective length of the adjust port by manual operation, and slightly moving the rear roll in the axial direction, aligning the roll unevenness (peaks and valleys). Is achieved. The clearance between the rolls is adjusted according to the hardness, material, grain size, etc. of the resin, but is usually about 0.11 to 0.3 mm or more. Adjusted to the left and right bearings of the other roll (for example, the roll 31 in front of each stage in Fig. 2) supported to be movable in the front-rear direction Screw 37a is fixedly attached, and index handles (index gauge dials) 37, 37 are provided at the ends thereof. Adjustment of the clearance is performed by rotating the index handle and moving the left or right or left or right bearing in the front-rear direction. In FIG. 3, only the index handles 37 and 37 on the right side of the frame are shown, and the index handle on the left side is not shown.

〔Manufacturing process〕

In the manufacturing process, the homogenization is performed using special rolls of several stages in the crushing and crushing sections. The roll shape (pitch, clearance) was emphasized in order to homogenize the bead size, and as a result, the bead particle size (size) was easily changed. It uses a different grinding method than conventional hammer mills, disk grinders, cone grinders, oscillators, and so on. In the crushing section and crushing section, a static electricity eliminator is installed to prevent static electricity from being generated in places (sites) where pressure, impact, shear, and friction occur on the material.

(Particle separation)

Dust containing fine particles generated at each stage from the crusher section to the classifier (sieving section) can be extracted from, for example, Patent No. 2891 163 1 (Japanese Patent Application Laid-Open No. Hei 8-252223). The particles are separated into reusable granular beads and dust by a granular separation device (dust treatment device) as disclosed in (1).

That is, the granular material separation device includes: a cylindrical separation container (separation chamber); a storage container formed on the outer periphery of the separation container; dust and renewable fine particles generated during the crushing step. (Beads) are blown into the separation container (2) together with compressed air, so that a carry-in tube is attached to the separation container through the side wall of the storage container; and is arranged in the separation container and is delivered from the carry-in tube. A diffusion member for diffusing and separating the dust and renewable beads obtained by the difference in mass, comprising a group of discs with punching holes or slits which are spaced apart from each other and stacked in several stages; A discharge pipe for dust provided on a side wall near the top of the containment vessel; and a tank disposed below the containment vessel and the separation vessel to accommodate renewable beads after dust separation. Is composed of I have.

(Configuration of separation vessel)

In addition, the separation container (separation chamber) discharges dust that has not passed through the diffusion member to a discharge pipe near the top of the storage container, and is higher than a bead receiving surface of the diffusion member. The storage container is further provided with a first discharge port, and the storage container is configured to discharge dust floating through the punching holes or slits of the diffusion member into the reusable bead storage tank and floating to the discharge pipe side. A second outlet is provided at the bottom of the containment tank, which is the upper plate of the storage tank.

According to the above separation device, the reusable beads and dust are extremely efficiently diffused by the diffusion member composed of a plurality of upper and lower punching holes or a group of disks with slits arranged in the separation container. As a result, the separation accuracy can be maintained at a high level.

The details of the particle separation device (dust treatment device) 28 are omitted from the drawings because they are disclosed in the aforementioned Japanese Patent No. 2891631, but the mixture of reusable beads and dust generated at each stage is suctioned. It is transported into the separation vessel (separation chamber) by duct 27. Since the dust collector 29 is operating, the inside of the separation vessel is under negative pressure. Therefore, the mixture of beads and dust blown from the inlet violently collides with the inner wall of the separation container, the lower surface of the inner lid, and the upper surface of the uppermost diffusion plate and diffuses at high speed. At this time, the dust is blown out from the first discharge port 46, passes through the space between the outer top surface of the separation container and the back surface of the containment container, reaches the discharge port 46, and is sucked into the dust collector 29. (Figure 2 ) .

[Structure and operation of diffusion plate]

Next, the reusable particles having a large mass and the dust not discharged from the first discharge port 46 pass through the respective punch holes or slits of the diffusion plate (not shown) and pass onto the diffusion plate. It falls and collides with the upper surface of the diffuser plate to diffuse. Here, the low-mass dust is again blown up, and is discharged from the first discharge port 46 through each punch hole or slit of the diffusion plate. Through these steps, finally, the reusable particles and the remaining small amount of dust that have passed through the diffusion plate fall down to the lower part of the hopper tank. (2) It is blown out from the discharge port (47) and discharged from the dust discharge port through the space between the outer wall and the inner wall of the separation container (28).

[Reuse of beads]

This section describes the reuse of beads during blasting. By spraying on the target object, the beads are crushed to reduce the particle size, and the sharp ridge portion is rounded. The beads are repeatedly reused by sieving using the separation device. Even if the bead diameter becomes smaller, the polyhedral shape of each particle and the grinding / peeling efficiency do not change. Target It can be reused several to several tens times (for example, 60 times) depending on the hardness of the product, the hardness of the beads, specific gravity, air pressure, spray angle, spray distance, etc. However, MG-14 (106 μm or less, for example, about 50 μm) does not recycle only once.

In this embodiment, not only the first discharge port 46 but also a second discharge port 47 for discharging dust and compressed air passing through the diffusion member is provided (FIG. 2). Therefore, the chance of blowing dust increases, and dust is prevented from being mixed into the reusable granules.

The first discharge port 46 is arranged to face the upper surface of the diffusion plate, which is the particle receiving surface of the diffusion member. Therefore, the dust diffused by the diffusion member can be easily blown out. In addition, the first discharge port 46 is disposed above the upper surface of the diffusion plate, which is the particle receiving surface of the diffusion member. Therefore, the possibility that the reusable beads having a large mass are blown out from the first outlet 46 is reduced, and as a result, the separation accuracy is improved.

In addition, a second discharge port 47 is provided above the hobba, which is a reusable granule storage tank. Accordingly, the possibility that the reusable granules having a large mass are blown out from the second discharge port 47 is reduced.

[Disposition of each part from crushing to packaging]

FIG. 7 is an arrangement diagram of each device showing another example from crushing to packaging. The beads crushed by the roll crusher 16 shown in FIGS. 2 and 3 are classified by the vibrating sieve 20. This vibrating sieve 20 has several stages of sieve nets 50 to 53 (for example, 6, 20, 32, 50 meshes) in which the stitches are sequentially made fine, and hits each sieve net. The shoots 50a to 53a from the outer wall of the sieve and the shoots 54 from the bottom of the lowermost sieve are led out and connected to the conveyor or ducts 55 to 59, respectively. Each sieve mesh 50 to 53 provided inside the vibrating sieve 20 can be replaced with any mesh, and the bead size is classified within the range from 10 mesh or less to 150 mesh. It is possible to do so.

The crusher 16 and the sieving machine 20 in FIG. 7 can be installed in two or more lines, but for simplicity of explanation, the case where only one line is used is illustrated and described.

Those with 6 mesh or more put in the duct 55 are sent to the crusher 15 and the crusher 16 where the foreign substances are removed and then crushed again.The powder transport conveyor or duct 56 Anything from 6 mesh to 20 mesh that has been put into the mash is classified as MG-7,10,14 by sieving. 20 mesh or less thrown into conveyor 57 ~ 32 mesh The items on the mesh are sent to the first bagging line 60 as MG-3, and those below the 32 mesh to 50 mesh that are input to the conveyor 58 are called MG-5. Sent to the second bagging line 80.

The first bagging line 60 is provided by a switching damper 61 provided at the downstream end of the conveyor 57, and is provided with a double-toned flexible container (flexible container) filling machine 62 and a 20 kg bagging machine 62. Connected to 0. The frecon packing machine 62 consists of a hopper with a level detector 63, a loading dang, ° 64, a frecon bag 65, a platform scale 66 and a conveyor 67, and a 20 kg bag filling machine Reference numeral 70 denotes a hopper 71 with a level detector, a hopper 72 with a weighing and sewing machine, a bag 74 and belt conveyors 75, 76.

The second bag-filling line 80 is a hopper 81 with a level detector, a screw conveyor 82, an input dumper 83, and a hood 81 with a level detector provided at the lowermost end of the powder transport conveyor 58. It consists of a phono with a measuring device, ° 84, and 20 kg packaging bags 86 are sequentially carried out by a conveyor.

[Example of beads]

During blast work, several beads made of thermosetting resin such as those described above are mixed. These beads 90 have a hardness (Mohs) of 3.0-4.5, specific gravity 1.:!~1.52, size 10 ~: L50 mesh (about 10000 ~: Ι Ο Ο) Ομπι), as shown in Fig. 8 (25 times), each forms an irregular polyhedron with sharp edges. However, it can be used even if it is 100 μm or less (for example, 50 μm). When shown as the predetermined air pressure (2~3 kg / cm ² or more pressure) 1 peeling due injected bi one's at 0 mm径No nozzle 1 capacity per this, beads ejection amount is 1. For 9 to 2.20 kg Zmin, the peel time per m ² is 3 to 6 mi m ² . The number of recycles of beads depends on the pressure, but is usually 15 to 40 or more.

The performance of the above beads is primarily specified by material, hardness and specific gravity, secondary is excellent in cutting performance, abrasion resistance, heat resistance, anti-static property, and tertiary is blast The work speed is high, the dust generation rate is low, the reusability is high, and the bead dust itself is pollution-free and can be treated as general waste.

Next, suitable conditions for the peeling operation will be described. ①Air pressure: 0-5 kg / cm 2 ②Nozzle diameter: 3, 4, 5, 6, 7, 8, 8.5 8.5 mm

③Adjust the mixing ratio of beads and air with a valve. ④Adjust the injection angle and distance to the shape of the object to be peeled.

MG-0 for peeling bumper chips, MG-1 for coating hard materials (steel materials) for removing oxide scale and road markings, MG-1 for coating films, rust, Paris, adhesives, seals, floor wax, etc. MG-3 or MG-15 for cleaning of peeling, anti-glare on metallic glossy surfaces, walls or tiles, coating film of soft material (such as aluminum) 'Rust' Burr. MG_7, soft for wall cleaning MG-10 or MG-14 is used for wall coating or floor cleaning.

[Test Example 1]

A 3 to 5 mm thick plastic plate-like molded product formed by heating and pressing a mixed material of 6% by weight of melamine resin and 40% of urea resin by a crusher. After being crushed into a batter shape, it was roughly crushed and pulverized by the above-mentioned device to obtain a release material of 20 to 65 mesh, which was sprayed on an aluminum can coating film to peel off the coating film.

The capacity of one 6 mm diameter nozzle is 2 kgcm ² air pressure and the amount of beads ejected is 1.

0 kg Zmin, 1 m ² per stripping time 3 niinZ m ² treated with result, it and this for 5 0 Mi click b down the coating film was released cleanly represent the gloss of the metal aluminum.

(Test Example 2)

A mixture of 70% of crushed resin plate and 30% of crushed resin plate was crushed by a crusher, and then crushed and pulverized. As a release material for 0 to 65 mesh, the coating film was peeled off by spraying it onto the aluminum can coating film, and the coating film was successfully removed as before.

(Test Example 3)

A crushed plate-like resin molded product molded from a mixed material of a melamine resin and a phenol resin is crushed and crushed by the above-mentioned equipment to obtain a mesh release material of 20 to 65, which is used as a steel can. The coating film was peeled off by spraying on the 100 micron coating film. 6 mm径No capacity per one nozzle is, the air pressure 3 kg / cm ^2, a bead ejection amount 1. O kg Zmin, 1 m 2 per stripping time 3 result treated with MinZm ^2, and cleanly peeled coating film A metallic luster could be exhibited. Industrial applicability

As described above, in the present invention, the present invention is characterized in that in the production process, after crushing in a crushing section, crushing and sieving are performed by several stages of crushing rolls, so that the crushing is performed at each classification step adapted to the purpose of work processing. Grinding or peeling beads with a uniform particle size can be easily manufactured. In particular, emphasis is placed on the shape of the crushing roll (concavo-convex pitch, clearance of the opposing roll), and grinding and polishing of various workpieces. In addition, irregular polyhedral beads suitable for instantaneous peeling can be provided. By selecting the shape of the crushing roll, it is easy to change and adjust the bead particle size, and it is possible to efficiently produce beads with less generation of dust and noise during the crushing process. In addition, the homogenization of the particle size of the beads improves the grinding and peeling ability, and can shorten the work time for instantaneous peeling and the like. Furthermore, beads that are useful for peeling work such as peeling off coatings on aluminum cans, steel cans, automobile bumpers, etc., and regenerating non-consumables can be efficiently used without damaging the peeled product (work). It can be manufactured.

Claims

The scope of the claims

1. Pulverized product of thermosetting resin molded product having a particle size in the range of 100 to about 50 μm, each particle being an irregular polyhedron with a sharp ridge line, and for each classification step Grinding beads characterized in that the particle size is almost uniform.

2-The thermosetting resin molded product is one or more selected from melamine, urine, fuynol, unsaturated polyester, acryl, guanamine, epoxy and polyurethane. Beads according to 1.

3. The beads according to claim 1, wherein the thermosetting resin molded product is a mixture of a melamine, a urine, and a phenolic or phenolic resin.

4. Fill the pulp and glass fiber cloth at the mixing stage of the resin material prior to the preparation of the molding material of the thermosetting resin, and further ripen and dry the carbon, artificial graphite, metal powder or The bead according to claim 1, wherein a metal fiber and a coloring material are blended.

5. Fill the pulp and glass fiber cloth pieces in the mixing step of the resin material prior to the preparation of the molding material of the thermosetting resin, and further ripen and dry the carbon, artificial graphite, metal powder or A plate-shaped resin molded product is made by blending metal fibers and a coloring material, and this resin molded product is crushed into a cyclo-like or pellet-like shape, and the concavities and convexities on the facing roll surface are formed with a phase shift of 12 pitches The crushed material of the thermosetting resin molded product is crushed to a particle size of 100 to about 50 μm by the multi-stage crushing rolls, so that each particle has a substantially sharp ridge line. A method for producing beads for grinding, characterized in that it has an amorphous polyhedral fine material.

6. 30 to 40% of pulp and 0.1 to 0.5% of glass fiber cloth flakes are blended into the thermosetting resin material after polymerization condensation. Carbon powder or artificial graphite with electrical conductivity of 0.2 to 0.3 for control, and metal powder or metal fiber of 0.1 to 0.5% for raising the specific gravity to 1.8 or more A method for producing the beads according to claim 5.

7. The plate-like resin molded product is one or two selected from melamine, urine, phenol, unsaturated polyester, acryl, guanamine, epoxy and polyurethane. 7. The method for producing beads according to claim 5, comprising the above.

16

Corrected form (Rule 91)

8. The method for producing beads according to claim 7, wherein the braided resin molded product is a mixture of a melamine, a urine or a phenolic resin.

9. The method for producing beads according to claim 8, wherein the plate-like resin molded product is obtained by mixing 30 to 20% of a urea resin with 70 to 80% of a melamine resin.

10. A plastic molded with at least two molding materials selected from the group consisting of melamine, urine, phenol, unsaturated polyester, ataline, guanamine, epoxy and polyurethane. 6. The method for producing beads according to claim 5, comprising crushing the resin-like resin molded products for each molded product, followed by mixing and crushing.

11 1. After crushing the plate-shaped resin resin molded product and the plate-shaped resin molded resin material into the shape of a cyclo or pellet, respectively, the former is 60 to 70%, The method for producing beads according to claim 10, wherein the latter is mixed at a ratio of 40 to 30% and pulverized.

12.The crushing roll for crushing the plate-like molded product of thermosetting resin into approximately 2 mm square, and the crushed material obtained by the crushing nozzle, with a particle size of 100 to about 50 μm In order to pulverize into an irregular polyhedron with a sharp ridgeline, a multi-stage pulverizer is formed, in which the concavities and convexities on the opposing roll surfaces are formed with a phase shift of 12 pitches. Production equipment for polishing beads.

1 3. Crusher No. 15 for crushing a plate-like molded product of thermosetting resin material into a shape like a mouth or a pellet,

A sorting unit that removes metal and foreign matter in the crushed material crushed by a part of the crusher, and a roll or pellet-like crushed material that has passed through the sorting unit 1 2 A crushing unit equipped with a pair of crushing rolls with irregularities of pitch phase shift,

Similar to the crushing roll, the crushed material obtained in the crushing section is crushed into an irregular polyhedron having substantially sharp ridges to a particle size of approximately 100 to approximately 50 μm. A crushing unit equipped with a multi-stage crushing roll pair having irregularities with 1 / 2-bit phase shift, and placed downstream of the crushing unit to make the particle size of the crushed beads almost uniform at each classification stage And a separation bead manufacturing device.

14. A thermoformed resin plate-like molded product is an irregular shape of about 2 to 4 mm square. A part of the crusher that crushes into a shape like a pellet, a separator that removes metal and foreign matter in the crushed material crushed by the part of the crusher, and a phase shift of 1/2 pitch between the pair of roll surfaces A crushing unit provided with at least one pair of crushing rolls and a static eliminator for crushing the crushed material selected in the sorting unit by forming irregularities having

The crushed material obtained in the crushing section is crushed into an irregular polyhedron having substantially sharp ridges to a particle size of approximately 100 to approximately 50 μm. A pulverizing unit equipped with a multi-stage pulverizing roll pair having irregularities having a phase shift of 1/2 pitch on the surface and a static eliminator,

An air classifier for classifying fine-grained beads and a power classifier for classifying finer-sized beads than the fine-grained beads arranged with a switching valve downstream of the pulverizing section;

The packaging and shipping department consists of weighing, bagging, and automatic sewing of beads classified by an air classifier or an electric power classifier to make a predetermined volume of peeled bead packaging.

In addition, a circulation line for returning the fine particles on the mesh of the air classifier and the power classifier upstream of the sorting section or upstream of the crushing section, and each stage from the crusher section to the classifier. And a duct for guiding the dust containing fine particles generated in the step to a dust treatment device.

15. A particle size adjusting mechanism for changing and adjusting the bead particle size by setting the unevenness pitch of the crushing roll and the clearance between the opposing rolls to be optimal. An apparatus for producing beads according to 4.

16. The classifying device was derived from a vibrating sieve having several stages of sieve meshes in order to classify beads crushed by the crusher, and a sieve outer wall corresponding to each sieve mesh. It consists of a shoot and a duct or a conveyor connected to each shoot.The first-stage mesh-up is sent to the crusher and crushed again, and the lower-most mesh under is discarded as dust. Claim 14 or Claim 14 wherein the items on the second and lower intermediate meshes are sent to a frecon packing machine or a 20kg bagging machine, weighed, bagged, and sequentially carried out. 15. The bead production apparatus according to 15.