DE29600344U1 - Container for mixing modeling plaster from gypsum powder and water - Google Patents

Description

Bremen, 23 April 1996

Our reference: K 1010 MAN/hs Applicant/Owner: Kerr Corporation, Michigang

Official reference number: 296 00 344.1

Bremen Patent Attorneys

European Patent Attorneys Dipl.-Ing. Günther Eisenführ Dipl.-Ing. Dieter K. Speiser Dr.-Ing. Werner W. Rabus Dipl.-Ing. Jürgen Brügge Dipl.-Ing. Jürgen Klingnardt Dipl.-Ing. Klaus G. Göken Patent Attorney Dipl.-Ing, Mark Andres Attorneys Ulrich H. Sander Christian Spintig

Munich Patent Attorneys

European Patent Attorneys

Dipl.-Phys. Gerhard Lied!

Dipl.-Wirtsch.-lng. Rainer Pritsche

Patent Attorney

Dipl.-Chem. Dr. Peter Schuler

Bertin Patent Attorney

European Patent Attorney Dipl.-Ing. Jutta Kaden

Martinistrasse 24 D-28195 Bremen Tel. 0421-36 35 0 Fax 0421-36 35 35 (G3> Fax 0421-32 88 631 (G4) MCI 585-0169

Kerr Corporation, 28200 Wick Road, Box 455, Romuius, Michigan 48174, U.S.A.

container
for mixing modelling plaster from plaster powder and water

New description

The invention relates to a container for mixing modeling plaster from gypsum powder and water.

The modeling plaster, which is mixed from gypsum powder and water, is used by dentists or dental technicians or their assistants to make models of teeth, which are referred to below as tooth models and are obtained in the usual way from impressions of teeth. The term tooth model is understood to mean a model of individual teeth or several teeth in a row of teeth, which can be prepared, i.e. ground or unprepared.

To produce the tooth models, the mixed modeling plaster is poured into a patient's dental impression made from an impression material. After the modeling plaster is poured into the impression, the modeling plaster hardens over time and, after hardening, is separated from the impression material to form a finished tooth model.

In the usual and well-known way, the modeling plaster is mixed by the dentist, dental technician or assistants by pouring plaster powder and water into an elastic rubber cup, manually mixing the filled plaster powder and water in the rubber cup using a mixing spoon or stirring rod, and then removing the mixed modeling plaster from the rubber cup and processing it further.

There are several disadvantages to this well-known approach:

When mixing the plaster powder with the water, contamination often occurs due to plaster escaping from the rubber cup, so that the work area becomes contaminated and modelling plaster is lost - even if only in small quantities.

Too much modelling plaster is also regularly mixed, i.e. more modelling plaster is mixed than is required to produce a tooth model from an impression. On the one hand, this means that the excess amount of plaster has to be disposed of, and on the other hand, costs arise due to the excess consumption of plaster powder.

When mixing the modelling plaster in a dental laboratory, the disadvantages mentioned are not so serious because the laboratory normally requires larger quantities of plaster than a dentist's office and the costs for cleaning as well as for purchasing and disposing of excess modelling plaster can be spread over a larger number of dental prosthesis production orders.

The disadvantages mentioned are more serious when making tooth models in a dentist's office, because the mixed plaster can usually only be used to make a tooth model for a single patient and the costs mentioned for cleaning as well as for purchasing and disposing of excess modeling plaster are therefore more significant.

The invention is based on the object of providing a container for mixing modeling plaster, with which contamination during mixing can be minimized and with which an amount of plaster can be mixed that is only required quite precisely for the production of a tooth model.

The object is achieved with a container of the type mentioned at the outset in that two tightly connected, separable container parts are provided, which together form a completely closed container, and that at least one closable opening is provided for filling and/or venting, which passes through the wall of at least one of the container parts.

The container according to the invention is pre-filled with the metered amount of plaster powder at the factory well before the modeling plaster is mixed, distributed to dentists' offices and laboratories and filled with water through the sealable opening shortly before mixing by the dentist or the laboratory. To fill the container with water, a syringe is preferably used, the needle of which is inserted through the sealable opening of the container. A pre-metered amount of water is then sprayed into the container. During the injection, either air can escape through one opening, or another opening is provided in the container through which the air can escape. After filling with water, one or both openings are closed and the container can be shaken manually or with the help of a shaking device so that the plaster powder is thoroughly mixed with the water. Since the container is completely closed by shaking during mixing, no plaster powder, water or modelling plaster can escape from the container, so that no contamination can occur at the workplace during mixing.

According to the invention, a precisely measured amount of modeling plaster can be mixed with a precisely measured amount of water in order to produce a predetermined amount of modeling plaster for an individual case, so that no excess modeling plaster is mixed. This can significantly reduce the costs of producing the tooth models.

According to an advantageous embodiment of the invention, the container parts can be partially pushed into one another in a sealing manner to form the closed container, in such a way that the peripheral edge sections formed on the container parts rest on top of one another in a clamping manner. This measure allows the container parts to be assembled in a particularly simple manner to form a closed container after the plaster powder has been filled into one of the container parts, and to be taken apart again in an equally simple manner in order to be able to remove the ready-mixed modeling plaster for further processing.

A further preferred embodiment of the container is characterized in that filling and venting openings are designed as through-holes through the edge sections and the container parts can be brought from a relative position in which the through-holes are aligned to a relative position in which one edge section covers the through-holes of the other edge section in a sealing manner. This embodiment also has the advantage that openings that can be opened and closed quickly are formed in the container in a particularly simple structural manner, through which water can be added to the container and air can escape from the container at the same time. The container parts are expediently designed to be rotationally symmetrical so that the filling and/or venting openings can be opened or closed by simply manually turning the container parts.

Another development of the invention provides that at least one of the container parts has a stand section formed on it, which has a standing surface lying in one plane or a lower edge lying in one plane, on which the container part can be placed with its edge section pointing upwards. The stand section means that the container parts can be placed at any time without additional holders, for example on a table top, in order to be pre-filled with plaster or to be able to remove the ready-mixed modeling plaster. In addition, the stand sections can be used to clamp the closed container into a shaker or vibrator for shaking during mixing.

The container is conveniently made of thin-walled plastic, which makes it easy and inexpensive to manufacture.

The invention is described below using a preferred embodiment with reference to the accompanying drawings. They show:

Figure 1 shows a container according to the invention composed of two container parts in a side view and

Figure 2 shows the container parts from Figure 1 forming the container in a

separated state in side view.

In Figure 1, the container 1 consisting of a first, lower container part 2 and a second, upper container part 4 is in a closed state

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in which the container parts 2 and 4 are partially pushed into one another in a sealing manner. The container 1 has a first closable opening 6 and a second closable opening 8.

The lower container part 2 has a peripheral edge section 10, and the upper container part 4 has a peripheral edge section 12. The container parts 2, 4 are inserted into one another in such a way that the edge section 10 of the lower container part 2 rests with its outer surface on the inner surface of the edge section 12 of the upper container part 4. The container parts 2, 4 are connected to one another by a clamping engagement. The outer surface of the edge section 10 and the inner surface of the edge section 12 are so close to one another that a seal is formed in the area of the edge sections 10, 12 lying one above the other. The quality of the seal and the ability to slide into one another depend essentially on the selected manufacturing tolerances of the edge sections 10 and 12 and the material properties and can be varied.

A closable filling opening 6 and a ventilation opening 8 are formed by through holes 14, 18, 16, 20 through the edge sections 10 and 12. To close the filling and ventilation openings 6, 8, the container parts 2 and 4 can be brought from a relative position in which the through holes 14 and 18 or 16 and 20 are aligned into a relative position in which one edge section 10, 12 sealingly covers the through holes 14, 18, 16, 20 of the other edge section 12, 10. The relative position of the container parts 2, 4 for closing or opening the filling and venting openings 6, 8 can be easily changed in the embodiment shown by the rotationally symmetrical container parts 2, 4 being able to rotate relative to the other container part about a central axis 21 running vertically in Figures 1 and 2. In a manner not shown, the container parts 2, 4 can be provided with corrugations or the like on their outer surfaces in order to be easier to grip with the hands, so that the container parts 2, 4 can easily be rotated relative to one another.

A standing section 22, 24 is formed on the lower and upper container parts 2, 4, each having a lower edge lying in one plane, on which the container part 2, 4 can be placed with its edge section 10, 12 pointing upwards. Instead of the lower edge, the standing section 22, 24 can alternatively have a standing surface lying essentially in one plane, on which the container part 2, 4 can be placed.

-D-

Both container parts 2, 4 of the container 1 are made of a thin-walled plastic.

The following describes the mixing of modeling plaster from plaster powder and water using the container according to the invention.

The sealable container 1 is filled with a precisely measured amount of gypsum powder in a state shown in Figure 2, in which the container parts 2 and 4 are completely separated from one another. The filling takes place relatively long before the gypsum powder is mixed with water. Alternatively, the container 1 can also be filled with a precisely measured amount of gypsum through the filling opening 6 in its state shown in Figure 1, in which the container parts 2, 4 are pushed into one another. During filling in this state, air in the container 1 can escape through the vent opening 8.

After filling the container 1 with gypsum powder, the container 1 is completely closed and the filling opening 6 and vent opening 8 are also closed by bringing the container parts 2, 4 into the relative position in which the edge sections 10, 12 cover the through holes 14, 16, 18, 20 of the respective other edge section 12, 10. The dosed gypsum powder can be stored in the completely closed container 1 for any length of time.

Immediately before mixing the modeling plaster, a precisely measured amount of water, which is required to produce optimal modeling plaster, is added to container 1. During the addition, container 1 is at least partially vented.

The amount of water can be added to the container 1 in various ways. A first possibility is that the filling opening 6 and the vent opening 8 are brought into the open position by bringing the container parts 2, 4 into the relative position in which the through holes 14, 18, 16, 20 are aligned. The needle of a syringe, which is filled with the precisely measured amount of water, is then partially inserted into the interior of the container 1 through the filling opening 6 and the amount of water contained in the syringe is injected into the interior of the container 1. During the injection of the water, air can escape from the interior of the container 1 through the vent opening 8, which makes it easier to inject the water.

A second way to enter the dosed water quantity is under

Use of a container according to the invention (not shown) which has only a vent opening 8 but no filling opening 6, in that the container parts 2, 4 are first brought into a relative position in which the vent opening 8 is open, and then the tip of a needle of a syringe, which is filled with the metered amount of water, is pierced through the walls of the thin-walled plastic container 1 in the area of the superimposed edge sections 10, 12 until the tip of the needle is completely inside the container 1. The amount of water can then be injected from the syringe into the interior of the container 1, while air can escape from the interior of the container 1 through the open vent opening 8, which facilitates the injection. After emptying the syringe, the needle is pulled out of the hole formed in the walls of the container 1 by piercing the tip. The container parts 2, 4 are then manually rotated relative to one another about the vertical axis 21, with the result that both the vent opening 8 and the hole formed by inserting the syringe needle in the area of the edge sections 10, 12 are closed.

After adding the water to the container 1, the amount of gypsum and water in the completely sealed container 1 are mixed by shaking the sealed container 1. Shaking the container 1 is preferably carried out by placing the container 1 in a shaking device, a special vibrator or the like and then allowing the mixing to take place for a while.

After mixing the plaster powder and water, the container 1 is removed from the shaking device or the vibrator. To do this, the container 1 is opened by completely separating the container parts 2, 4 from one another. The mixed modeling plaster can then preferably be removed from the lower container part 2 for processing.

After removing the mixed modelling plaster, the container parts 2, 4 can be cleaned and reused.

Claims (7)

Expectations 1. Container for mixing modeling plaster from gypsum powder and water,
characterized in that two tightly connected, separable container parts (2, 4) are provided, which together form a completely closed container, and in that at least one closable opening (8) for filling and/or venting is provided, which passes through the wall of at least one of the container parts (2, 4). 2. Container according to claim 1, characterized by a closable filling opening (6) and a separate closable vent opening (8). 3. Container according to one of claims 1 and/or 2, characterized in that the container parts (2, 4) can be partially pushed into one another in a sealing manner to form the closed container, such that peripheral edge sections (10, 12) formed on the container parts (2, 4) lie one above the other in a clamping manner. 4. Container according to claim 3, characterized in that filling and venting openings (6, 8) are designed as through-holes (14, 18, 16, 20) through the edge sections (10, 12) and the container parts (2, 4) can be brought from a relative position in which the through-holes (14, 18, 16, 20) are aligned into a relative position in which one edge section sealingly covers the through-holes of the other edge section. 5. Container according to at least one of the preceding claims,
characterized in that the container parts (2, 4) are rotationally symmetrical. 6. Container according to at least one of the preceding claims, characterized in that a standing section (22, 24) is formed on at least one of the container parts (2, 4), which has a standing surface lying in one plane or a lower edge lying in one plane, on which the container part (2, 4) can be placed with its edge section (10, 12) pointing upwards. 7. Container according to at least one of the preceding claims, characterized in that the container (1) consists of thin-walled plastic.