CN1169450A - Chalk, ifs making method and special moulding machine - Google Patents
Chalk, ifs making method and special moulding machine Download PDFInfo
- Publication number
- CN1169450A CN1169450A CN 96116416 CN96116416A CN1169450A CN 1169450 A CN1169450 A CN 1169450A CN 96116416 CN96116416 CN 96116416 CN 96116416 A CN96116416 A CN 96116416A CN 1169450 A CN1169450 A CN 1169450A
- Authority
- CN
- China
- Prior art keywords
- chalk
- calcium carbonate
- carbonate powder
- extrusion
- total weight
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Landscapes
- Inks, Pencil-Leads, Or Crayons (AREA)
Abstract
The present invention discloses a chalk, its making method and special forming machine thereof. Said invention is characterized by that it uses calcium carbonate powder as its main ingredient, uses binder as its auxiliary ingredient, but without gypsum, those are made in the form of straight cylinder or straight prism. Said invented special forming machine can be a multi-hopper multiscrew extrusion machine which possesses high production efficiency.
Description
The invention relates to a chalk, a manufacturing method thereof and a special forming machine.
The traditional chalk is calcined gypsum powder (CaSO)4)2·H2O is mixed with a small amount of light calcium carbonate powder CaCO3Adding a proper amount of water, uniformly mixing to obtain grout, pouring the grout into a die with a plurality of material cavities arranged in parallel, and reacting the calcined gypsum with the water as follows:
The invention aims to provide a novel chalk, which can not easily fly dust to avoid influencing the health of a user; the manufacturing method is suitable for machine production, not only improves the production efficiency, but also lightens the labor intensity and is beneficial to keeping stable quality; the invention also provides a chalk forming machine special for the manufacturing method.
The purpose of the invention is realized as follows: a chalk whose chemical composition contains 98-99.8% of calcium carbonate powder, the rest is adhesive and additive whose content is less than one thousandth of the total weight of the chalk, it contains no gypsum, and the shape of said chalk is a straight cylinder or a straight prism; the chalk does not contain gypsum, and the original traditional manufacturing method of solidification molding in a die is not suitable, and the adopted manufacturing method comprises thefollowing steps of preparing a binder liquid by adding a binder and an additive in a specified proportion to the total weight of the chalk and a proper amount of water, fully and uniformly mixing calcium carbonate powder and the binder liquid in a specified proportion to the total weight of the chalk, kneading the materials in a kneader, putting the materials into a hopper of a special chalk molding machine, performing extrusion molding, cutting the materials according to a fixed length, and then performing drying treatment, wherein the chalk is manufactured in an extrusion molding mode, so that the chalk is in a straight column shape; the chalk forming machine specially designed for realizing the extrusion forming step in the manufacturing method comprises a machine frame and a plurality of material cavities which are arranged in parallel, a plurality of hoppers which are also arranged on the material cavities in parallel and are respectively communicated with the material cavities, an extrusion screw rod driven by a transmission mechanism is arranged in each material cavity, an extrusion hole of each material cavity has a shape corresponding to the cross section of the chalk, and a screw rod which plays a pressing role and is also driven by the transmission mechanism is also arranged in each hopper.
The chalk of the invention overcomes the indispensable traditional appearance of gypsum in the chalk compositionThe chalk is characterized in that the chemical composition of the chalk is calcium carbonate powder which is mainly gypsum-free, the chalk is molded in an extrusion mode after a material kneading step, so the chalk has a compact structure and high density, and the specific gravity of the chalk is about 1.6 g/[ cm]after being tested]3The specific gravity of the traditional gypsum chalk is 0.75 g/[ cm]]3The chalk has a smooth and smooth hand feeling during writing, and the problem of hardening caused by water can be avoided by adopting an extrusion molding mode for machine production because the raw materials of the chalk do not contain calcined gypsum powder, so that the heavy labor mainly caused by manual work in the past is avoided, and the machine production is also favorable for maintaining stable quality, high quality and high efficiency; the production of the product is not restricted by weather and sunny and rainy days; the formula can be adjusted according to the requirements, so that the hardness of the chalk can meet the requirements of different users.
The chalk, its manufacturing method and special forming machine of the present invention will be described in detail with reference to the accompanying drawings and examples.
Fig. 1 is a schematic external view of a chalk of the present invention.
FIG. 2 is a flow chart of the manufacturing method of the chalk of the present invention.
Fig. 3 is a schematic front view of a chalk molding machine specially designed for implementing the extrusion step in the chalk manufacturing method of the present invention.
Fig. 4 is a schematic side view of the chalk forming machine shown in fig. 3.
Fig. 5 is a schematic sectional top view A-A of the chalk forming machine shown in fig. 3.
Fig. 6 is a schematic partial sectional view of the chalk forming machine B-B shown in fig. 3.
Referring to fig. 1, there are shown two most commonly used exterior views of chalks of the present invention, the left side of which is a front view and a top view of a right hexagonal prism-shaped chalk, and the right side of which is a front view and a top view of a right cylindrical chalk, whichare both straight cylinders and conventional chalks are easy to release during manufacture, and are usually not straight cylinders with slopes at both ends; the chalk comprises 98-99.8% of calcium carbonate powder in chemical composition, the balance of adhesive and additive with content less than one thousandth of the total weight of the chalk, and no gypsum, wherein the calcium carbonate powder can be prepared by mixing heavy calcium carbonate powder and light calcium carbonate powder in various proportions, the heavy calcium carbonate powder is prepared by grinding natural light calcium carbonate mineral, the powder quality of the heavy calcium carbonate powder is slightly coarser than that of light calcium carbonate powder prepared by a chemical method, the heavy calcium carbonate powder and the light calcium carbonate powder are commercially available, the heavy calcium carbonate powder has high content and hard hand feeling, the light calcium carbonate powder has high content and soft hand feeling, wherein the light calcium carbonate powder is not less than 10% and not more than 50%, the light calcium carbonate powder is expensive, the low content can influence the smooth extrusion molding, and the high cost is caused by the high content; the binder can adopt polyvinyl alcohol or carboxymethyl cellulose used for preparing chemical pulp paste, or can be a mixture of the polyvinyl alcohol and the carboxymethyl cellulose in various weight proportions; the additives added to the raw materials of the chalk of the present invention may be various water-soluble substances for further improving its properties.
Referring to fig. 2, there is shown a flow chart of the chalk manufacturing process of the present invention, which comprises preparing binder liquid, charging carboxymethyl cellulose, polyvinyl alcohol, additives and water into a stirrer, mixing uniformly, charging light calcium carbonate powder and heavy calcium carbonate powder, mixing uniformly, charging into a material kneading machine, kneading to make the raw materials more uniform and compact, adding into a hopper of a specially designed chalk forming machine, extruding, cutting to length, using photoelectric controlled automatic cutting machine to achieve accuracy and high efficiency, feeding the cut chalk into a drying tunnel through a conveyor belt, charging hot air into the drying tunnel through a hot air boiler, inspecting and packaging to obtain the final product.
Referring to fig. 3, 4, 5 and 6, since the chalk of the present invention contains no gypsum in its chemical composition and the raw material for making the chalk does not contain calcined gypsum powder which is not reacted with water and is hardened into gypsum, the method of solidification molding adopted in the traditional chalk making is not suitable, but is suitable for machine production by adopting the method of extrusion molding, the chalk forming machine specially designed for realizing the extrusion molding step in the chalk making method of the present invention comprises a frame (1) and a plurality of material cavities (2) which are arranged in parallel, the lower parts of a plurality of hoppers (3) which are also arranged in parallel on the material cavities (2) are respectively communicated with the material cavities (2), an extrusion screw rod (5) driven by a transmission mechanism (4) is arranged in each material cavity (2), a material pressing screw rod (7) also driven by the transmission mechanism (4) is arranged in each hopper (3), the extrusion port of the material cavity (2) adopts a template which is fixedly connected with the material cavity (2) and can be detached, and the template is provided with an extrusion hole (6) corresponding to the cross section of the chalk. Here, three parallel chambers (2) and correspondingly three parallel hoppers (3) are shown in the figures, each chamber (2) having four extrusion orifices (6), and a total of twelve extrusion orifices (6) being extruded simultaneously during operation.
Claims (5)
1. A chalk is composed of calcium carbonate powder (98-99.8 wt.%), adhesive (and additive (less than one thousandth of the total weight of chalk), and features no gypsum and straight cylinder or prism.
2. The chalk of claim 1, wherein the calcium carbonate powder accounts for 98% to 99.8% of the total weight of the chalk, and the light calcium carbonate powder accounts for 10% to 50% of the total weight of the chalk, and the balance is heavy calcium carbonate powder.
3. The chalk of claim 1, wherein the binder is selected from the group consisting of carboxymethylcellulose and polyvinyl alcohol.
4. A process for preparing the chalk as defined in claim 1 includes such steps as mixing raw materials with water, shaping, drying, proportionally mixing it with adhesive and additive, proportionally mixing it with calcium carbonate powder, proportionally mixing it with adhesive, kneading, extruding out, cutting and baking.
5. A chalk forming machine specially designed for implementing the extrusion forming step in the manufacturing method of claim 4, which comprises a frame (1) and a plurality of material cavities (2) arranged in parallel, and is characterized in that a plurality of hoppers (3) respectively communicated with the material cavities (2) are also arranged in parallel above the material cavities (2), an extrusion screw (5) driven by a transmission mechanism (4) is arranged in each material cavity (2), an extrusion hole (6) of each material cavity (2) has a shape corresponding to the cross section of the chalk described in claim 1, and a screw rod (7) which is also driven by the transmission mechanism (4) and plays a role of pressing materials is also arranged in each hopper (3).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 96116416 CN1169450A (en) | 1996-07-03 | 1996-07-03 | Chalk, ifs making method and special moulding machine |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 96116416 CN1169450A (en) | 1996-07-03 | 1996-07-03 | Chalk, ifs making method and special moulding machine |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN1169450A true CN1169450A (en) | 1998-01-07 |
Family
ID=5123521
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 96116416 Pending CN1169450A (en) | 1996-07-03 | 1996-07-03 | Chalk, ifs making method and special moulding machine |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN1169450A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102442106A (en) * | 2011-09-23 | 2012-05-09 | 李雄军 | Chalky teaching chalk and manufacturing method thereof |
| CN106113559A (en) * | 2016-08-18 | 2016-11-16 | 浙江机电职业技术学院 | A kind of chalk molding educational institution |
| CN111907242A (en) * | 2020-08-17 | 2020-11-10 | 宁波润爵科技有限公司 | Chalk manufacturing device |
-
1996
- 1996-07-03 CN CN 96116416 patent/CN1169450A/en active Pending
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102442106A (en) * | 2011-09-23 | 2012-05-09 | 李雄军 | Chalky teaching chalk and manufacturing method thereof |
| CN106113559A (en) * | 2016-08-18 | 2016-11-16 | 浙江机电职业技术学院 | A kind of chalk molding educational institution |
| CN111907242A (en) * | 2020-08-17 | 2020-11-10 | 宁波润爵科技有限公司 | Chalk manufacturing device |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP0545163B1 (en) | Process for the manufacturing of bricks | |
| CN111592330B (en) | Stoneware brick blank, preparation method thereof and stoneware brick | |
| CN101786830B (en) | Preparation method of artificial stone with marble-imitated Sha Anna high-grade variety pattern and artificial stone prepared thereby | |
| CN1169450A (en) | Chalk, ifs making method and special moulding machine | |
| CN1052675C (en) | Method for making plate-like article and resulting article | |
| EP1428809A3 (en) | Process for production of formed honeycomb body, and honeycomb structure | |
| JP2592103B2 (en) | Extrusion molding die for foamed lightweight cement board and extrusion molding method using the same | |
| CN114425813B (en) | High-strength compact phosphogypsum-based aggregate molding preparation system and preparation method | |
| WO2001085642A1 (en) | Process for making extrusions for producing multi-property tiles and obtained tiles | |
| KR100197035B1 (en) | Preparation of disposable container using starch | |
| CN101555344A (en) | Urea-formaldehyde resin compound flowerpot and manufacture method and device thereof | |
| CN1074362C (en) | Manufacture of porcelain rockery | |
| CN2384782Y (en) | Pencil extruder | |
| CN2183861Y (en) | Multifunctional brick and tile making machine with function of separating stones from clay column | |
| CN1113857A (en) | Method for producing plastic pencil | |
| CN1103023A (en) | Synthetic timber and making method | |
| CN109096683A (en) | A kind of ink inkstone and preparation method | |
| CN1164474A (en) | Pencil | |
| CN1468734A (en) | Chalk producing process | |
| CN206416488U (en) | Co-extrusion decorative wall panels mould | |
| CN106316304A (en) | Cement products and preparation methods thereof | |
| CN1069450A (en) | Health chalk and production technique thereof | |
| CN2796993Y (en) | Inner lining device for extrusion mouth of brick making machine | |
| CN115230184A (en) | Natural texture artificial stone plate manufacturing device and manufacturing method thereof | |
| SU1070128A1 (en) | Method for making cellular concrete products |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C01 | Deemed withdrawal of patent application (patent law 1993) | ||
| WD01 | Invention patent application deemed withdrawn after publication |