glass container

Abstract

Glass vessel (11, 11'), in particular evaporation flask, for a laboratory device (30), in particular a rotary evaporator, with a vessel body (12) made of glass, which defines a receiving space (17) for a medium to be heated, in particular a liquid, characterized by at least one heating resistance element (20) which is in thermally conductive contact with the vessel body (12) and has a connection (23) for supplying electrical energy, wherein the connection (23) comprises at least two sliding contact surfaces (25) which surround a neck (15) of the flask-shaped glass vessel (12).

Description

[0001] The present invention relates to a glass vessel, in particular an evaporation flask, for a laboratory device, in particular a rotary evaporator, with a vessel body made of glass, which defines a receiving space for a medium to be heated, in particular to be evaporated.

[0002] Such glass vessels are used in a variety of ways in laboratory technology, for example, to heat liquids, powders, and the like. They are required, for instance, to operate rotary evaporators, shake mixers, stirrers, and dispersers. These glass vessels often have a flask shape, meaning they consist of a bulbous body and a neck, which serves as a filling opening and / or a steam outlet.

[0003] Heating a medium in a glass vessel can be achieved, for example, using a heating bath. In this process, the glass vessel is immersed in a heat transfer fluid such as water or oil, which is itself heated, for example, electrically. To ensure even heating, the glass vessel can be rotated in the heating bath. However, the hot heat transfer fluid poses a certain risk of burns. Furthermore, the heat transfer fluid must be added to and emptied from the heating baths, which is time-consuming and laborious for the operator.

[0004] Laboratory equipment with so-called dry heaters, such as mushroom heaters, heating trays, or heating cups, is also known. These dry heaters operate without a heat transfer fluid. However, with such laboratory equipment, the glass vessel must be inserted into the heating chamber, which requires more effort. Furthermore, dry heaters have a comparatively poor heat transfer, resulting in correspondingly higher energy consumption.

[0005] German patent DE 196 08 297 A1 describes a heatable reaction vessel which has a thermally contacting heating device in the form of a heating coil that wraps around the vessel in several turns. The electrical connections of the heating coil are fixed, so the vessel is not movable.

[0006] US Patent 3,177,341 A discloses a vessel which is attached via a heated clamp and therefore cannot be moved.

[0007] The purpose of the invention is to make heating a medium in laboratory equipment simpler, more effective and safer.

[0008] The problem is solved by a glass vessel having the features of claim 1.

[0009] A glass vessel according to the invention comprises at least one heating resistance element which is in thermally conductive contact with the vessel body and has a connection for supplying electrical energy, wherein the connection comprises at least two sliding contact surfaces which encircle a neck of the bulb-shaped glass vessel. In the case of multiple heating resistance elements, these can be arranged, for example, in parallel, delta, or star connection, depending in particular on the type of power supply or the number of external conductors of the power supply present or used.

[0010] The heating element allows the glass vessel, including any medium it contains, to be heated directly, i.e., without the use of a heat transfer fluid and without convection. Since heating occurs exclusively via thermal conduction, efficient use of the supplied electrical energy is ensured. Until now, it has generally been assumed in laboratory technology that glass vessels in laboratory equipment are heated by heating elements integrated into the equipment. Deviating from this general principle, the invention proposes integrating the heating element into the glass vessel itself, rather than into the laboratory equipment. Accordingly, the laboratory equipment only needs to be supplied with an electrical power source. Because the glass vessel and the heating element essentially form a single unit, fewer components are required overall.Because the connection includes at least two sliding contact surfaces that encircle the neck of the bulb-shaped glass vessel, reliable electrical contact between the device's power supply and the vessel's heating element is ensured even when the glass vessel rotates, for example, when the evaporation bulb of a rotary evaporator rotates. The sliding contact surfaces can be ring-shaped and applied to the outer surface of the bulb's neck. Three sliding contact surfaces might be used, for example, when operating a heating element with three-phase current, four rotating sliding contacts when operating two resistance wires with single-phase current, and so on.

[0011] Further developments of the invention are specified in the dependent claims, the description and the accompanying drawing.

[0012] Preferably, the heating element comprises a resistance wire. Resistance wires are inexpensive and can be easily applied to a glass surface or integrated into a glass body. Preferably, the resistance wire has a diameter of at most 1.5 mm, and more preferably at most 0.5 mm. When using such fine resistance wires, the overall transparency of the glass vessel can be maintained. An operator thus has a clear view of the medium being heated.

[0013] The heating element can be applied to an outer surface of the vessel body, in particular by printing or gluing. This ensures particularly simple manufacturing. If necessary, existing glass vessels can also be retrofitted with a heating element in this way.

[0014] According to a specific embodiment of the invention, the heating resistance element applied to the outer surface of the vessel body is at least partially covered by a film, which is designed as a composite film and / or is electrically insulating. Such a film allows the heating resistance element to be shielded from the outside in a simple and cost-effective manner.

[0015] As an alternative to externally mounting the heating element, it can also be integrated into the vessel body. For example, a resistance wire can be embedded in the glass vessel body. This allows for particularly good heat transfer. If more than one heating element is provided, at least one heating element can be mounted on an outer surface of the vessel body, and at least one heating element can be integrated into the vessel body.

[0016] The vessel body can be designed as a laminated glass component comprising at least two bonded glass panes, with the heating element arranged between these at least two glass panes. Such a design is particularly advantageous in applications where, for safety reasons, the vessel body must already be manufactured using laminated glass construction. The heating element can be easily inserted between the two glass panes during manufacturing.

[0017] According to a further embodiment of the invention, a glass vessel comprises a temperature sensor attached to the vessel body for detecting the temperature of the vessel body and / or a medium located in the receiving chamber. The concept of a functional glass vessel is thus extended insofar as the means for temperature detection are also assigned to the glass vessel and not to the laboratory equipment. The temperature sensor can be a simple thin-film element. The temperature detected by the temperature sensor can be output to a higher-level control unit, which in turn controls or regulates the heating of the medium based on the temperature signal.

[0018] Specifically, the temperature sensor can extend into the recording chamber to immerse itself in the medium within. This allows for direct measurement of the medium's temperature.

[0019] The temperature sensor can also be integrated into the vessel body. For example, the temperature sensor could be designed as a thin-film element and inserted between two glass panes of a laminated glass component. A preferred embodiment of the invention provides that both the heating element and a temperature sensor are integrated into the vessel body.

[0020] The connection can comprise at least two sliding contact surfaces, preferably with the sliding contact surfaces circling around a neck of the bulb-shaped glass vessel. This ensures that even when the glass vessel rotates, for example, when an evaporation bulb of a rotary evaporator rotates, a reliable electrical contact is always maintained between the device's power supply and the vessel's heating element. The sliding contact surfaces can be designed in a ring shape and applied to the outer surface of the bulb neck of an evaporation bulb. Three sliding contact surfaces can be provided, for example, when operating a heating element with three-phase current, four rotating sliding contacts when operating two resistance wires with single-phase current, etc.

[0021] A particular embodiment of the invention provides that the heating element is arranged helically around the vessel body, in particular having a uniform serpentine pattern, wherein the heating element extends over at least 50% and preferably over at least 80% of the surface of the vessel body. This enables particularly uniform heating of a medium located in the glass vessel.

[0022] The invention also relates to a laboratory device, in particular a rotary evaporator, with a glass vessel as described above, in particular an evaporation flask.

[0023] According to the invention, a heating power supply unit is provided which can be connected to the heating element to supply electrical energy to the heating element. The heating power supply unit can be housed in a casing of the laboratory device. A device-side connection element of the heating power supply unit can be specifically designed for connecting the heating element of a glass vessel typically used with this laboratory device. For example, in a rotary evaporator, the device-side connection element can be integrated into the rotary drive. The laboratory device can thus be manufactured more cost-effectively overall, since only the electrical power supply unit, and not a separate heating element, needs to be provided.

[0024] A resistance detection device, particularly integrated into the heating power supply unit, may be provided, which is designed to detect the electrical resistance of the heating element. The detected electrical resistance of the heating element can be used for various testing purposes.

[0025] Additionally, a temperature measurement device can be provided, which is designed to determine the temperature of the glass vessel and / or a medium located in the recording chamber based on the measured electrical resistance. Preferably, the laboratory device is designed to measure the electrical resistance of the heating element directly via the connection. This allows for a particularly simple design.

[0026] A control unit can be provided which is designed to control and / or regulate the electrical energy supplied to the heating element based on the measured temperature. This allows for a particularly simple and controlled heating of a medium contained in a glass vessel.

[0027] A control unit may also be provided, which is designed to control and / or regulate the electrical energy supplied to the heating element based on a temperature sensor detected by a temperature sensor attached to the vessel body, in particular one integrated into the vessel body or extending into the glass vessel. The temperature sensor may be manufactured using thin-film technology. In certain applications, a separate temperature measurement from the resistance measurement may be advantageous.

[0028] The invention is described below by way of example with reference to the drawings. Fig. Figure 1 shows a glass vessel according to a first embodiment of the invention. Fig. Figure 2 shows a glass vessel according to a second embodiment of the invention. Fig. Figure 3 shows a laboratory device according to the invention in schematic form.

[0029] The in Fig. The illustrated glass vessel 11 comprises a glass body 12, which is shaped like a flask and has a bulb 13 and a neck 15. In the illustrated embodiment, the bulb 13 is spherical and the neck 15 is cylindrical, as is common in many evaporation flasks. The interior of the bulb 13 defines a receiving chamber 17 for a liquid to be heated. One end of the neck 15 defines an opening 19 through which liquids can be poured into the receiving chamber 17 or through which vapor can escape. The glass vessel can also be used, for example, to heat a powder.

[0030] The glass vessel 11 is equipped with a heating resistance element 20, which comprises a thin resistance wire 21. The resistance wire 21 is located in the Fig. In the embodiment shown in Figure 1, the resistance wire 21 is wound in a helical pattern around the piston body 13 in evenly spaced paths, resulting in a uniform and complete covering of the piston body's surface. The two ends of the resistance wire 21 are connected to sliding contacts 25, which are ring-shaped and encircle the piston neck 15. The two sliding contacts 25 form a terminal 23, specifically a positive and a negative pole, for supplying electrical energy to the heating element 20. When the terminal 23 is supplied with electrical current, the resistance wire 21 heats up, and consequently, so does the glass of the vessel body 12. A liquid located in the receiving chamber 17 can thus be heated directly and without transmission losses.

[0031] Depending on the application, the resistance wire 21 can be applied to the outer surface 27 of the vessel body 12 or be completely integrated into the glass of the vessel body 12. For example, the resistance wire 21 can be printed or glued onto the outer surface 27 of the vessel body 12. If necessary, the resistance wire 21 can be covered by a film, which in Fig. 1, however, is not shown. The vessel body 12 could also be designed as a laminated glass component and comprise at least two interconnected glass panes. In this case, the resistance wire 21 could be arranged between the two glass panes of the laminated glass component. The in Fig. The glass vessel 11 shown can also be equipped with a temperature sensor separate from the heating resistance element 20 for detecting the temperature of the vessel body 12 and / or a liquid located in the receiving chamber 17. Such a temperature sensor can, in particular, be manufactured using thin-film technology and, like the resistance wire 21, can be applied to the outer surface 27 of the vessel body 12 or integrated into the vessel body 12, depending on the application.

[0032] The in Fig. The glass vessel 11' shown in Figure 2 is basically designed similarly to the one in Figure 2. Fig. 1 Glass vessel 11 shown. However, the resistance wire 21 is not straight here, but follows a serpentine pattern 29 to enable particularly effective heating.

[0033] Fig. Figure 3 shows in schematic form a laboratory device 30, which includes a glass vessel 11 like the one in Fig.The glass vessel 11 shown in Figure 1 can be designed as an evaporation flask and attached to a rotary drive (not shown) of the laboratory apparatus 30, which is designed as a rotary evaporator.

[0034] The laboratory device 30 comprises a heating power supply unit 31 and an electronic control unit 33 for regulating the heating power supply unit 31. Heating current can be supplied to the heating element 20 of the glass vessel 11 via a supply line 35, which is in contact with the terminal 23 of the glass vessel 11. The heating power supply unit 31 is also designed to detect the electrical resistance of the heating element 20. The detected electrical resistance can be transmitted to the control unit 33 via a bidirectional data line 39. Based on the detected resistance value, the control unit 33 can determine the temperature of the vessel body 12 or of the liquid in the receiving chamber 17. Using the determined temperature, the electronic control unit 33 regulates the energy supplied to the heating element 20 by communicating accordingly with the heating power supply unit 31 via the data line 39.

[0035] Due to the heating element integrated directly into the glass vessel 11, it is not necessary to equip the laboratory device 30 with a heating bath, a heating mantle, or a heating canister. This keeps manufacturing costs and space requirements low. Furthermore, the operation of the laboratory device 30 is particularly simple, as the glass vessel 11 does not need to be immersed in heat transfer fluids or placed in heating chambers.

[0036] Unlike the figures shown, several heating resistance elements can also be provided, which, for example, when operated with an AC power supply, can be connected in parallel to each other and each between the two sliding contacts 25. The preceding statements regarding the single heating resistance element 20 then apply – insofar as applicable – to each of the multiple heating resistance elements.

[0037] It is understood that glass vessels for laboratory equipment, which are equipped with integrated resistance heaters according to the principles of the invention, can be used in various laboratory devices such as rotary evaporators, mixing devices and the like. Reference symbol list 11, 11' glass vessel 12 blood vessels 13 Piston belly 15 Piston neck 17 Recording room 19 Opening 20 heating resistance element 21 resistance wire 23 connection 25 sliding contact 27 outdoor area 29 samples 30 laboratory equipment 31 Heating power supply unit 33 electronic control unit 35 Supply line 39 Data line

Claims

[1] Glass vessel (11, 11'), in particular evaporation flask, for a laboratory device (30), in particular a rotary evaporator, with a vessel body (12) made of glass, which defines a receiving chamber (17) for a medium to be heated, in particular a liquid, characterized by at least one heating resistance element (20) which is in thermally conductive contact with the vessel body (12) and has a connection (23) for supplying electrical energy, wherein the connection (23) comprises at least two sliding contact surfaces (25) which surround a neck (15) of the bulb-shaped glass vessel (12). [2] Glass vessel according to claim 1, characterized by , that the heating resistance element (20) comprises a resistance wire (21). [3] Glass vessel according to claim 1 or 2, characterized by , that the heating resistance element (20) is applied to an outer surface (27) of the vessel body (12), in particular printed or glued on. [4] Glass vessel according to claim 3, characterized by , that the heating resistance element (20) applied to the outer surface (27) of the vessel body (12) is at least partially covered by a film which is designed as a composite film and / or is electrically insulating. [5] Glass vessel according to claim 1 or 2, characterized by , that the heating resistance element (20) is integrated into the vessel body (12). [6] Glass vessel according to claim 5, characterized by , that the vessel body (12) is designed as a laminated glass component comprising at least two interconnected glass panes, wherein the heating resistance element (20) is arranged between the at least two glass panes. [7] Glass vessel according to any of the preceding claims, characterized by a temperature sensor attached to the vessel body (12) for detecting the temperature of the vessel body (12) and / or of a medium located in the receiving chamber (17). [8] Glass vessel according to claim 7, characterized by, that the temperature sensor extends into the receiving chamber (17) to immerse itself in a medium located therein. [9] Glass vessel according to claim 7, characterized by , that the temperature sensor is integrated into the vessel body (12). [10] Glass vessel according to any of the preceding claims, characterized by , that the heating resistance element (20) is arranged helically around the vessel body, in particular having a uniform serpentine pattern (29), wherein the heating resistance element (20) extends over at least 50% and preferably over at least 80% of the surface of the vessel body (12). [11] Laboratory apparatus (30), in particular rotary evaporator, comprising a glass vessel (11, 11'), in particular an evaporation flask, according to one of the preceding claims, characterized by a heating power supply unit (31) which can be connected to the connection (23) of the heating resistance element (21) in order to supply electrical energy to the heating resistance element (21). [12] Laboratory apparatus according to claim 11, characterized by a resistance detection device, in particular integrated into the heating current supply unit (31), which is designed to detect the electrical resistance of the heating resistance element (31). [13] Laboratory apparatus according to claim 12, characterized by a temperature measuring device (33) which is designed to determine the temperature of the glass vessel (11, 11') and / or a medium located in the receiving chamber (17) based on the detected electrical resistance. [14] Laboratory apparatus according to claim 13, characterized by , that a control unit (33) is provided which is designed to control and / or regulate the electrical energy supplied to the heating resistance element (20) on the basis of the determined temperature. [15] Laboratory apparatus according to claim 11, characterized by, that a control unit (33) is provided which is designed to control and / or regulate the electrical energy supplied to the heating resistance element (20) on the basis of a temperature detected by a temperature sensor attached to the vessel body (12), in particular integrated into the vessel body (12) or extending into the glass vessel (11, 11').

Images