Evaporator device for an incubator, incubator and method

Abstract

The invention relates to an evaporator device and to a method for generating a water vapor for humidifying an incubator atmosphere by means of a heating surface of the evaporator device, wherein water is conducted by means of a water conducting device so that it flows along the water conducting device as far as the heating surface, which evaporates the water.

Description

[0001] Evaporator device for an incubator, incubator and process

[0002] The invention relates to an evaporator device for a laboratory device with an incubation function, in particular an incubator for the growth of microorganisms, especially cells. The invention also relates to a laboratory device with this evaporator device and a method for humidifying an incubator atmosphere.

[0003] Incubation-capable laboratory equipment, such as incubators or incubated shakers, is used in biological and medical laboratories to maintain samples under controlled environmental conditions. The temperature, gas composition, and humidity of the atmosphere inside an incubator chamber, which is isolated from the surrounding environment, are maintained at the desired levels by the incubator's internal components. Controlling the humidity within the incubator is crucial, as it influences the growth and development of embryos, cells, or microorganisms. Different types of organisms require different humidity levels; therefore, precise humidity control is essential to ensure optimal incubation conditions. Incubators for cell culture enable the growth of living cells in vitro under defined atmospheric conditions.Eukaryotic cells require CO2 incubators. The atmosphere is created by air with a specific CO2 and O2 content and a specific humidity; a suitable temperature is often 37 °C.

[0004] The interior of an incubator or incubated shaker must be regulated with high humidity. Relative humidity levels of around 85–95% are typical. This can be achieved passively by maintaining the temperature of an open water surface within the incubation chamber, or actively by controlling the amount of evaporated water introduced into the chamber. High and reproducible humidity is crucial to prevent the evaporation of medium from incubated cell cultures, which would concentrate their components. Reproducibility is a core requirement of cell culture experiments, so conditions within the incubation chamber must always be consistently controlled. Another important aspect is ensuring condensation-free surfaces within the incubation chamber to prevent contamination in these areas.

[0005] Passive humidification using open water surfaces in incubators has the significant practical disadvantage that open water surfaces pose a high risk of contamination, particularly from fungi. The risk of spillage when removing water trays is also a problem, as is the large amount of space required within the incubation chamber, which cannot be used effectively. Furthermore, this method is passive and cannot be set to specific target values. With actively controlled evaporator systems, the challenge lies in ensuring that the water to be evaporated is produced reproducibly in very small doses to prevent unevaporated water from entering the incubation chamber, which would lead to condensation on surfaces.

[0006] Known evaporators allow water to drip onto the surface of the heating element, as is provided, for example, in DE 10 2005 030822 A1. These arrangements, as demonstrated in the experiments underlying this invention, have the disadvantage that steam is generated in an uncontrolled manner, since the Leidenfrost effect can occur at high surface temperatures. If the temperature at the interface is sufficiently high to allow rapid primary evaporation, the water droplet moves on a cushion of vapor that protects it from direct heat exchange. This vapor cushion forms under the droplet and escapes only slowly. Simultaneously, new water vapor is continuously generated, causing the droplet to appear to glide over the hot surface. Since droplets are never perfectly symmetrical, random droplet movements occur on the surface, leading to uncontrolled evaporation.Such arrangements are therefore not optimal for precise humidity control.

[0007] The invention is based on the objective of providing an evaporator device for a laboratory device with an incubation function that enables controlled evaporation.

[0008] The invention solves the problem by means of the evaporator device according to claim 1, the laboratory device according to claim 14 and the method according to claim 15. Preferred embodiments of these items are specified in the dependent claims and can also be found in the description of the invention and in the figures.

[0009] The evaporator device is preferably a component of a laboratory instrument. It is specifically designed for connection to the incubation chamber of a laboratory instrument used for the incubation of microorganisms, particularly living cells. In such an evaporator device, the humidity in the chamber is actively controlled by generating and supplying steam to the chamber in a metered manner as needed. According to the invention, the precise water metering necessary for controlled evaporation is achieved by the evaporator device having a water guide system. This system allows the water entering the evaporator chamber from the water inlet opening to flow along the water guide system to the heating surface. In particular, the water guide system directs the water to an edge of the heating surface.This arrangement prevents drops from falling onto the heating surface and thus, in particular, avoids a release of water vapor that can no longer be precisely controlled in terms of timing.

[0010] Preferably, the water guidance device is designed such that the water conveyed through the water inlet opening flows onto the water guidance surface and / or flows on the water guidance surface, in particular in the form of a water film on the water guidance surface, especially without a free water droplet falling onto the heating surface.

[0011] Preferably, the water guidance device has a water guidance surface, which is preferably arranged between the water inlet opening and the heating surface. Preferably, the water guidance surface is in contact with the heating surface. However, a small gap between the water guidance surface and the heating surface is also permissible, provided that the water can flow freely to the heating surface, particularly without the water falling onto the heating surface. The water guidance surface is preferably in thermal contact with the heating surface. The water guidance surface preferably begins at the water inlet opening. The water guidance surface is preferably in contact with the mouth of the water inlet opening. The water guidance surface is preferably planar. The water guidance surface may also be curved in sections.The water flow surface is preferably arranged vertically when the evaporator device is in its intended mounted position.

[0012] The water guidance surface can be designed, in particular hydrophilically, by means of a suitable surface structure and / or choice of material or by a coating with a suitable material, so that the water flowing along the water guidance surface has the form of a water film, or that the water droplet on the water guidance surface shows a contact angle that is less than 90 degrees or 60 degrees or 45 degrees.

[0013] The position of the water inlet opening is such that the water entering the chamber can be guided to the heating surface by the water guidance system. The water inlet opening can be located above, beside, or even below the heating surface with respect to gravity.

[0014] The cross-sectional area of ​​the water inlet opening preferably has a maximum diameter between 0.5 mm and 20 mm, preferably between 1 mm and 5 mm, and preferably between 2 mm and 4 mm. These small diameters, in particular, allow for precise metering of the water supplied to the evaporator chamber.

[0015] The water guide surface fulfills its purpose as a water-carrying element when water flows along it due to gravity. During operation, the evaporator is mounted such that the heating surface is located below the water inlet opening with respect to the direction of gravity. A small volume of water supplied by the water pump through the water inlet opening will then flow along the water guide surface without striking the heating surface in free fall. It is possible for the water to fall onto the water guide surface, as long as direct contact with the heating surface is avoided. Preferably, the evaporator chamber has a wall section, particularly an inner wall section, that forms or incorporates this water guide surface. This inner wall section preferably extends from the water inlet opening to the heating surface.

[0016] The water guide surface preferably does not run horizontally and preferably runs vertically when the evaporator device is mounted on the wall of an incubation chamber of a laboratory device during intended use. The water guide surface preferably does not run horizontally and preferably runs at an angle α to the horizontal when the evaporator device is mounted on the wall of an incubation chamber of a laboratory device during intended use, so that water can flow along the water guide surface by gravity, in particular so that no drops fall onto the heating surface. Preferably 80° ≤ α ≤ 175°.

[0017] During operation, the evaporator device is mounted in such a way that the heating surface is located below the water inlet opening with respect to gravity. A small volume of water, supplied by the water pump through the water inlet opening, will then flow along the water guide surface without striking the heating surface in free fall. It is possible for the water to fall onto the water guide surface, as long as direct contact with the heating surface is avoided.

[0018] The water-guiding surface fulfills its purpose as a water-carrying element even if there is no gravity-driven water flow along it. In particular, the water-guiding surface can be arranged so that the water conveyed from the water inlet opening into the chamber is transported via the water-carrying device to the heating surface. The necessary energy or electrical power for this can be supplied by the water-carrying device, thus eliminating the need for gravity-driven flow. For example, the water-guiding surface can run horizontally, especially between the water inlet opening and the heating surface. As long as the water can be conveyed to the heating surface, the water-guiding surface can also direct a volume of water upwards, driven in particular by the water-carrying device or by capillary action.In particular, the water-guiding surface can be the inner surface of a tubular structure, especially a pipe or hose, which can extend from the water inlet opening to the heating surface.

[0019] The vapor outlet is preferably located above the heating surface when the vaporizer is mounted on the wall of an incubation chamber of laboratory equipment during normal use. The laboratory equipment is positioned on a horizontal surface during normal use, so the vaporizer is oriented relative to the equipment. This orientation is essential because liquid samples in incubation chambers are typically stored in open containers that allow gas exchange between the inside of the container and the incubator atmosphere. Culture vessels for microorganisms, especially cells, are usually designed for storage on horizontal surfaces.

[0020] Preferably, the evaporator device includes a water recirculation system, through which condensate, particularly that occurring in the area between the steam outlet and the heating surface, can be returned along the water recirculation system to the heating surface. The water recirculation system prevents condensate from accumulating near the steam outlet in the evaporator device or even from accumulating in the steam outlet itself. Pressure fluctuations in the evaporator chamber can sometimes cause water to be unpredictably expelled near the steam outlet towards an incubation chamber connected to the steam outlet. Furthermore, uncontrolled water backflow can lead to uncontrolled evaporation if varying amounts of condensate come into contact with the heating surface over an unpredictable period and are re-evaporated.

[0021] Preferably, the water recirculation device is arranged in thermal contact with the heating surface. Since the water recirculation device remains constantly heated in this case, the water recirculation is even more controllable compared to unheated water recirculation devices, as has been demonstrated in experiments.

[0022] Preferably, the evaporator device has a vapor outlet channel extending along a longitudinal axis between the evaporator chamber and the vapor outlet opening. The vapor outlet channel can be cylindrical. The vapor outlet channel can be closed in the direction of the vapor outlet opening by an end wall, which preferably includes this vapor outlet opening. The end wall is preferably substantially planar and alignable parallel to a plane E. The end wall is preferably arranged to be parallel to the side wall of an incubation chamber and / or, in particular, to be connectable to the side wall. The longitudinal axis preferably runs at an angle β to the normal of the plane E, where preferably 0 < β ≤ 90 degrees, preferably 2 <= β ≤ 60 degrees, and preferably 3 <= β ≤ 60 degrees. Due to this inclination of the vapor outlet channel relative to the horizontal, the condensate flows back to the heating surface in a controlled manner by gravity.

[0023] Preferably, the water return device has a water return surface that preferably extends in a direction parallel to the longitudinal axis of the steam outlet channel. This direction is preferably inclined at the aforementioned angle β to the normal of the plane E. The water return surface can be part of a bottom section of the outlet channel. Alternatively, the water return surface can be part of a water guide element arranged along this direction on the bottom section of the steam outlet channel.

[0024] The water return surface can be formed in particular by a return channel that is formed in an inner wall of the steam outlet channel or that is formed by a bottom section of the steam outlet channel and that extends between the steam outlet opening and the heating surface.

[0025] Preferably, the water return system includes a water guide element, in particular a pin element, extending between the steam outlet opening and the heating surface. The water guide element can have a higher thermal conductivity than the inner wall of the steam outlet channel. The water guide element can be made of or consist of metal. Preferably, the water guide element is arranged in thermal contact with the heating surface. Preferably, the water guide element is arranged in the return channel or in the bottom section of the steam outlet channel. The water guide element allows for even more controlled water flow and return.

[0026] Preferably, a spring mounting is provided so that the water guide element is spring-mounted, particularly between the steam outlet opening and the heating surface, and contacts the heating surface. This allows the water guide element to be inserted into the water return system with an installation tolerance provided by the spring. Furthermore, the spring-mounted water guide element is pressed against the heating surface, ensuring (thermal) contact with it.

[0027] Preferably, the steam outlet opening and the water return device are components of a connecting element with which the evaporator device can be mounted on the side wall of an incubation chamber.

[0028] The connecting element preferably has a fastening section, which is in particular a plate section, especially a disc element. The plate section particularly includes the steam outlet opening. The plate section preferably includes an end wall that closes the steam outlet channel. The steam outlet opening is preferably arranged eccentrically to the longitudinal axis of the steam outlet channel in the end wall.

[0029] The connecting element preferably has an engagement section, which may in particular be hollow cylindrical. The engagement section is designed to be guided through an opening in the side wall of an incubation chamber into the evaporator chamber, thereby connecting the evaporator device to the side wall. The vapor outlet channel preferably runs within the engagement section. The engagement section extends along an axis that preferably extends perpendicular to the plate section.

[0030] The evaporator chamber preferably has a receiving section in which the engagement section of the connecting element can be received. Preferably, at least one sealing element is provided to seal this engagement. The plate section preferably has at least one recess, in particular a bore, so that the plate section can be connected to a wall section of the evaporator device, in particular by means of screws.

[0031] The evaporator chamber is an interior space bounded by at least one wall section. The evaporator chamber is preferably formed in a component that has the required structure through shaping. This shaping is achieved in particular by a machining process or a casting process, especially a plastic injection molding process. The size of the evaporator chamber can vary depending on the size of the heating surface, in particular between 1 cm² and 1 cm². 3 and 50 cm 3The evaporator chamber is an enclosed space with a heating surface located along a section of the wall, particularly a section of the floor. The evaporator chamber also has a water inlet and a steam outlet.

[0032] The evaporator device preferably comprises a first component. The evaporator device preferably comprises a second component. The first and second components are preferably connected to each other. The first and second components are preferably made of plastic. The first and / or the second component are preferably injection-molded parts. However, they can also be manufactured by a machining process, in particular by milling and turning. The plastic can be, in particular, polyetheretherketone (PEEK) or polyphenylene sulfide (PPS). The first and second components can also be manufactured integrally and then represent sections of a single component.

[0033] The first component is preferably connectable to the side wall of an incubation chamber of a laboratory device in a mounted position. Preferably, the first component, in the mounted position, supports the other components of the evaporator device, in particular the second component.

[0034] Preferably, an insulating device is provided that surrounds the first and / or second component. This thermally insulates the evaporator device and / or the adjacent side wall of the incubation chamber of the laboratory device in the assembled position. The insulating device can consist of one or more insulating parts, in particular foam parts. A foam part can be made of or contain silicone foam.

[0035] The first component preferably contains the evaporator chamber. The evaporator chamber is preferably cylindrical. An interior space, particularly of the first component, is defined as an evaporator chamber, which is bounded by wall sections, especially those formed by the first component. These wall sections include, in particular, a first side wall, which has the water inlet opening. The wall sections include and / or form, in particular, the steam outlet opening and, in particular, the steam outlet channel. A bottom section of these wall sections has, in particular, a wall opening for a heating element. Preferably, a further bottom section of the steam outlet channel has a recess extending parallel to a longitudinal axis of the steam outlet channel (or extending in a plane that also contains the longitudinal axis), in which a water guide element is arranged. This axially extending recess opens, in particular, into the wall opening.

[0036] The first component preferably comprises at least one wall section of the evaporator chamber. The first and / or the second component preferably comprises a receiving space for a heating unit. The receiving space is preferably cylindrical. The first component preferably has a wall section of the evaporator chamber that includes a wall opening. The heating unit, in particular the heating surface of the heating unit, preferably engages in this wall opening. Preferably, the heating unit forms a bottom section of the evaporator chamber.

[0037] The first component preferably has a bearing section designed for mounting on the side wall of an incubation chamber. The bearing section may include a centering section that engages positively with a steam inlet opening in the side wall of the incubation chamber. The bearing section also has a flat section, which is specifically designed for resting against the side wall of the incubation chamber.

[0038] The heating unit preferably comprises a heating block. This block is preferably made of a metal, in particular stainless steel, aluminum, or brass, or is preferably composed of such a metal. The heating block has a heating surface, preferably at least partially on its upper surface. The heating block is preferably at least partially cylindrical. The heating block is preferably slidable into the receiving space, which is preferably cylindrical. The heating block preferably has a heating element receptacle, in particular at least partially cylindrical, for receiving a heating element. The heating element is preferably a heating cartridge, in particular at least partially cylindrical, which has electrical connections for operating the heating cartridge. The heating element preferably includes an electric heater, in particular a resistance heater, for heating the heating surface. The heating element and the heating block can also be formed integrally.

[0039] The heating surface preferably has a central section. The heating surface is preferably at least partially planar. Preferably, the central section of the heating surface is planar, in particular circular. Preferably, the central section forms a bottom section of the evaporator chamber and / or preferably projects into the evaporator chamber. Preferably, the heating surface has a side section, in particular arranged at an angle to the central section, which extends obliquely or vertically downwards from the central section, in particular at an angle of 185° to 270°.

[0040] The heating surface is formed, in particular, by the head section of a heating block projecting into the evaporator chamber. The head section preferably has the shape of a truncated cone, the upper surface of which is, in particular, the central section. The head section can also be cylindrical, spherical segment-shaped, or cuboid-shaped. Preferably, the water guide surface, especially measured at least in the direction of gravity, runs perpendicular to the central section of the heating surface. The heating block preferably has a recess for receiving a temperature sensor. The heating unit preferably includes the temperature sensor, which is preferably inserted into this recess.

[0041] The heating unit is preferably positioned at a distance from the side wall of the incubation chamber of the laboratory device when the evaporator is mounted on the incubation chamber. A planar section of the connecting element runs, in particular, in a plane to which the heating unit is positioned at this distance. This distance is the minimum distance between the heating unit and the planar section and is measured, in particular, perpendicular to the planar section, i.e., especially when the evaporator is mounted, along the horizontal plane. This distance reduces the thermal impact on the incubator chamber caused by the high temperature of the heating surface.

[0042] The evaporator device can have at least one shield element which, when the evaporator device is mounted, is positioned between the side wall of the incubation chamber of the laboratory device and the heating unit. The shield element reduces heat transfer between the side wall of the incubator and the heating unit, thus providing insulation.

[0043] The first component preferably has a water connection receptacle, which is particularly cylindrical. It opens, in particular, into the water inlet opening. The evaporator device preferably has a water connection element. This engages, in particular, with the water connection receptacle. Preferably, a sealing element is provided that is arranged between the water connection receptacle and the water connection element. The water connection element preferably has an engagement section, which is particularly cylindrical and engages with the water connection receptacle. A water line, in particular a pipe or hose element, is preferably connected between the water connection element and the water supply device in a liquid-tight manner. The water connection element preferably includes a water supply channel.The evaporator device preferably has a water supply channel that opens into the water inlet opening, wherein, in particular, the cross-sectional area of ​​the water inlet opening is smaller than the cross-sectional area of ​​the water supply channel. Preferably, a reservoir chamber with a cross-sectional area larger than that of the water supply channel is arranged between the water supply channel and the water inlet opening. The cross-sectional area is measured perpendicular to the flow direction.

[0044] The steam outlet channel preferably extends at least partially along its longitudinal axis, with the steam outlet opening having a smaller cross-sectional area than a cross-section of the steam outlet channel measured perpendicular to the longitudinal axis. The steam outlet channel can be cylindrical or conical, or it can have the shape of a conic section or an oblique cone.

[0045] The cross-sectional area of ​​the steam outlet preferably has a maximum diameter between 0.5 mm and 20 mm, preferably between 2 mm and 10 mm, and preferably between 3 mm and 5 mm. The steam outlet may also have several smaller openings with a maximum cross-sectional area of ​​less than 2 mm, or be formed by or covered by a mesh element. A mesh element reduces unwanted droplet formation at the steam outlet.

[0046] Preferably, the steam outlet opening is arranged eccentrically to the longitudinal axis of the steam outlet channel. The steam outlet opening is preferably located above the heating surface forming the bottom of the evaporator chamber, and particularly above the longitudinal axis, when the evaporator device is mounted on a vertical side wall of an incubation chamber during intended use. This arrangement has proven particularly effective in preventing droplet formation. The more condensate droplets are formed, the more difficult it becomes to precisely control the steam output of the evaporator device.

[0047] The water supply system is preferably formed by a pump. The pump can be a micro-dosing pump, a diaphragm pump, a peristaltic pump, a screw pump, or a piezoelectric pump. The water supply system can also be configured for gravity-fed water delivery. For this purpose, the water supply system preferably includes a throttling device and a water inlet. The throttling device is preferably configured to receive water from the water inlet and, after throttling the water pressure or flow rate, to discharge the water. The throttling device is preferably located below the water inlet and allows a metered water flow along the direction of gravity. The incoming water can, in particular, originate from a water reservoir or water connection arranged above the throttling device or the water supply system.The throttling device is electrically controllable and designed to control the size of a water pipe cross-section and thus the flow of water.

[0048] Preferably, the pump device is configured to operate with a defined pumping capacity. For this purpose, a pumping capacity parameter can be predefined for the pump device. This parameter can be, in particular, a pump frequency, a duty cycle in the case of PWM control of the pump, a voltage, a current, or, in particular, the time course of such a signal. Preferably, the pump device is configured to generate a number of pump strokes, in particular such that this number of pump strokes results in a vaporizable quantity of water, which is conveyed through the water inlet opening onto the water conveying device and reaches the heating surface. The pumping capacity, in particular the number of pump strokes, can be predefined or controlled, and can, in particular, be controllable depending on a measured heating power of the heating surface.

[0049] It is also possible for the pumping device to be configured to generate a pump stroke, in particular such that—essentially—each pump stroke results in a vaporizable quantity of water or a vaporizable droplet that is conveyed through the water inlet opening onto the water supply device and reaches the heating surface. This ensures controllable water evaporation, which occurs in incremental metering volumes, corresponding to a droplet or a water film delivered to the heating surface.

[0050] Preferably, the water pumping device is characterized by at least one of the following technical specifications: a) the water pumping volume is between 1 pl and 50 pl, preferably between 5 pl and 20 pl, preferably between 10 pl and 20 pl, preferably between 7 pl and 15 pl, preferably between 9 pl and 11 pl; b) the minimum water pumping rate is between 0.5 pl / h and 100 pl / h, preferably between 0.5 pl / h and 20 pl / h, preferably between 0.5 pl / h and 10 pl / h.

[0051] Preferably, the evaporator device incorporates an electronic control unit. This unit is specifically designed to control the water delivery system and the heating surface. This control unit is preferably also designed to control the steam output rate of the evaporator device. This control is carried out with the aim of regulating the humidity in an incubation chamber connectable to the steam outlet, in particular by defining the water delivery rate of the water delivery system via a frequency-controlled electrical signal with an input frequency.

[0052] The water delivery device can also be designed as a metering device, which is configured to dispense a predetermined metered volume that reaches the heating surface and is evaporated there. This can be achieved, in particular, by the metering device having at least one piston that displaces and dispenses the defined volume of water from the piston chamber, especially by means of a water conveying device, in particular a pipe section or capillary, directly to the heating surface.

[0053] The control device is in particular connected to a temperature sensor which is arranged to detect the temperature of the heating surface.

[0054] The control device is preferably configured to set or regulate the temperature of the heating surface to a target temperature, which is selected, in particular, from the range between 100 °C and 250 °C and is preferably between 140 °C and 200 °C, more preferably between 170 °C and 190 °C. The electrical control device includes, in particular, a data processing unit and is preferably programmed to detect the temperature of a heating unit, especially the heating surface, and, in particular, to adjust the power output of the heating unit as a function of this temperature. Preferably, the control device is programmed to regulate the temperature of the heating unit, in particular a heating block or, in particular, the heating surface, to a desired, in particular, constant, target temperature.Preferably, the control device is programmed to form a heating control circuit which is configured to regulate the temperature of a heating element of the evaporator, measured by means of a temperature sensor, to a constant target temperature at which a volume of water coming into contact with the heating element is evaporated and thereby extracts heat from the heating element.

[0055] The electronic control unit is preferably programmed to control at least one function of the evaporator device, in particular the supply of water through the water inlet opening by means of the water pump, and / or the heating of the heating surface, and / or the measurement of the temperature of the heating element. The electronic control unit is preferably programmed to acquire data containing information from a sensor of the laboratory device and, in particular, to control the at least one function of the evaporator device based on this data. The sensor can, in particular, be a humidity sensor that measures the humidity in the incubation chamber of the laboratory device. The sensor can also be a door sensor that detects whether a door closing the incubation chamber is open or closed.In particular, it may be possible to change the steam output rate of the evaporator device depending on this data, for example to quickly increase the steam output rate after the door has been opened (and then closed again) in order to restore the desired relative humidity, e.g. 95%, in the incubation chamber as quickly as possible.

[0056] The functions of the control unit are implemented primarily through program code and / or electronic circuits. The control unit may include a microcontroller, a processing unit (CPU) for data processing, or a microprocessor, each of which may be assigned to the data processing unit.

[0057] The control device can be designed as an independently operating component that controls the functions of the evaporator device, but in particular does not control one or more functions of the laboratory device to which the evaporator device is connected or of which the evaporator device preferably is a part.

[0058] The control unit can also be a control unit that, in addition to the functions of the evaporator device, also controls at least one, several, or all functions of the laboratory equipment to which the evaporator device is connected or of which the evaporator device preferably forms a part. One of the functions of the laboratory equipment is, in particular, the control of the temperature in the incubation chamber of the laboratory equipment, or the control of the gas composition in the incubation chamber, especially the CO2 concentration. Another function of the laboratory equipment is, in particular, the control of a user interface module of the laboratory equipment that displays information to the user, especially about sensor values ​​relating to physical or chemical quantities measured in / on the incubation chamber.

[0059] The invention further relates to a laboratory device for incubating samples in an incubation chamber, in particular an incubator for incubating live cell cultures or a shaker with incubation function, which has an evaporator device according to the invention.

[0060] An incubator is a laboratory device. Specifically, an incubator is a laboratory device with an incubation chamber whose atmosphere can be regulated to a predetermined target temperature. It is a laboratory device used to create and maintain controlled climatic conditions (temperature, gas, and humidity) for various biological development and growth processes. An incubator can be a shaker incubator, meaning it has a mechanism for moving objects within the incubation chamber, or it can be a microbial incubator (even without CO2). An incubator can also be designed as a cell culture device.The incubator serves in particular to create and maintain a microclimate with controlled gas, and / or humidity, and / or temperature conditions in the incubator chamber, whereby this treatment may be time-dependent. The laboratory incubator, in particular a treatment unit of the laboratory incubator, may in particular include a timer, especially a time switch, a heating / cooling device, and preferably a setting for controlling an exchange gas supplied to the incubator chamber, a setting device for the composition of the gas in the incubator chamber, in particular for setting the CO2 and / or O2 and / or N2 content of the gas, and / or a setting device for setting the humidity in the incubator chamber.

[0061] The incubator, in particular a treatment unit of the incubator, comprises in particular the incubator chamber, and further preferably a control unit with at least one control loop, to which at least one heating / cooling device is assigned as the actuator and at least one temperature measuring device as the measuring element. The temperature in the incubator can be regulated by means of the control unit. Depending on the embodiment, the humidity can also be regulated via this unit.

[0062] Preferably, the incubator has the evaporator device according to the invention, by means of which the humidity in the atmosphere of the incubator chamber is adjusted.

[0063] CO2 incubators are used especially for the cultivation of animal or human cells.

[0064] Incubators may include turning devices for turning the at least one cell culture container and / or a shaking device for shaking or moving the at least one cell culture container. The incubator according to the invention is specifically not a bioreactor or fermenter.

[0065] The incubator may have at least one sensor device. A sensor device may, in particular, have at least one temperature sensor, preferably a plurality of temperature sensors. A temperature sensor may, for example, be a Pt100 or Pt1000 temperature sensor. A sensor device preferably has a sensor for determining a relative gas concentration, in particular for determining the CO2 and / or O2 and / or N2 content. A sensor device preferably has a sensor for determining the relative humidity.

[0066] An incubator preferably has one or a single incubator chamber. This chamber can be subdivided into compartments. Compartments can be separated by support plates, particularly perforated ones, thereby enabling gas exchange between the compartments.

[0067] The incubator chamber has chamber walls or inner chamber walls and exactly one or at least one chamber opening through which the objects or cell culture containers inside the incubator chamber can be placed and removed. This chamber opening can be closed by a closing element movably connected to the incubator chamber and / or its housing, in particular an incubator door movably mounted on the incubator chamber or the housing by means of a hinge or pivot device, and in particular one or more chamber doors. An incubator can have one or more inner doors, which may be transparent, and can have an outer door, which may be non-transparent, that thermally insulates the incubator chamber and, if applicable, at least one inner incubator door that closes or opens the chamber opening from the environment.An enclosure assembly can include frame components and / or frame walls and / or enclosure walls. A pivoting mechanism can include pivoting arms that allow the incubator door to pivot away from the chamber opening, in particular, to pivot completely away.

[0068] In the closed position of the chamber opening, the interior of the incubator chamber is preferably insulated from the environment in such a way that a desired temperature or atmosphere, controlled by the incubator, can be set, and in particular regulated, inside. In the open position of the chamber opening, gas exchange between the environment of the incubator and the interior of the incubator chamber is possible through this opening. The chamber opening is typically located in a front wall of the incubator that surrounds the chamber opening.

[0069] The incubator chamber preferably has several walls or inner wall surfaces, which can be joined together in one piece and, in particular, without edges. The walls or inner wall surfaces are preferably essentially planar, but can also have a curved shape, either entirely or partially. The incubator chamber is preferably cuboid in shape, but can also have other shapes, e.g., spherical, ellipsoidal, or polyhedral. The walls or inner wall surfaces are preferably made of a corrosion-resistant material, in particular stainless steel, or a plastic, in particular a composite plastic. This facilitates the cleaning / disinfection of the chamber interior. Independent of the chamber opening, which serves for loading / removing objects or cell culture containers, the incubator chamber can have at least one port for inserting a suitably dimensioned device or...a cable connection from inside the incubator chamber to its outside or to the surrounding area of ​​the incubator.

[0070] A side wall of the incubator chamber has, in particular, a steam inlet opening that is connected to the steam outlet opening of the evaporator device, preferably in a fluid-tight manner. This side wall of the incubator chamber also has, in particular, a mounting section for attaching the evaporator device. The mounting section can include the steam inlet opening, in which a connecting element for connecting the evaporator device to the side wall is preferably arranged.

[0071] A typical internal volume of an incubator chamber is between 50 and 400 liters (dm³). 3 ).

[0072] The incubator can have exactly one incubator chamber, but it can also have several incubator chambers, the humidity of which (or: temperature, relative gas concentration) can be adjusted individually or collectively. An incubator can have several incubator chambers, each of which can have its own chamber opening and its own chamber door for closing the chamber opening. Each of these incubator chambers, or a group of these incubator chambers, can be connected to an evaporator device according to the invention in order to adjust or regulate the humidity individually or for a group.

[0073] The incubator can have a housing, in particular a housing, which partially or completely surrounds the incubator chamber. An evaporator device according to the invention is preferably arranged within the housing, particularly next to the incubator chamber. The housing can be substantially cuboid in shape and can, in particular, be designed such that the incubator is stackable.

[0074] The invention also relates to a system comprising a number N>1 of incubators and at least one evaporator device according to the invention, in particular a number M>=1 of evaporators according to the invention, preferably M=N, each of which is individually connected to an incubator chamber. Preferably, the system includes a water reservoir, which is arranged, in particular, above a stack of the N incubators. When a pump is used as the water supply device, the water reservoir can also be arranged below the pump, thus increasing flexibility in setup. The water reservoir is connected to the water supply device of each of the evaporators. The system is specifically designed such that, when several of these incubators are in operation, water from this single water reservoir is evaporated by the evaporators of these incubators.

[0075] The invention also relates to a method for generating water vapor for humidifying the atmosphere of an incubation chamber of a laboratory device, in particular an incubator for incubating living cell cultures, by means of an evaporator device having a heating surface, in particular an evaporator device according to the invention, wherein water is guided by means of a water guide device along the water guide device to the heating surface which evaporates the water.

[0076] Further preferred embodiments of the invention, in particular of the method according to the invention, can be found in the description of the evaporator device or the laboratory device with incubation function and their preferred embodiments. Furthermore, additional embodiment options of the invention are shown in the exemplary embodiments in the figures. Identical parts of the exemplary embodiments are essentially characterized by the same reference numerals, unless otherwise described or evident from the context. The figures show:

[0077] Fig. 1a shows a cross-section through a perspective side view of the evaporator device according to an embodiment of the invention, in mounted position on the side wall of an incubation chamber of an incubator, without the water pumping device.

[0078] Fig. 1b shows a cross-section through a perspective side view of the evaporator device according to Fig. 1a with modified steam outlet channel, in mounted position on the side wall of an incubation chamber of an incubator, without the water pumping device.

[0079] Fig. 2a shows a cross-section through a perspective side view of an evaporator device according to an embodiment of the invention.

[0080] Fig. 2b shows a detail of Fig. 2a.

[0081] Fig. 3a shows a perspective side view of the evaporator device of Fig.

[0082] 2, from a viewing angle obliquely from the front and below, without the water pumping device.

[0083] Fig. 3b shows a perspective side view of the evaporator device of Fig. 3a, from a viewing angle obliquely from behind and above, without the water conveying device.

[0084] Figs. 4a to 4e each show an embodiment of the connecting element having the steam outlet channel, which can be used to connect the evaporator device according to Figs. 1a to 3b to the side wall of an incubation chamber.

[0085] Fig. 5a shows a schematic front view of an embodiment of the evaporator device according to an embodiment of the invention.

[0086] Fig. 5b shows a schematic front view of a system consisting of a stack of evaporator devices according to Fig. 5a, connected to a common water reservoir.

[0087] Fig. 5c shows an embodiment of a laboratory device according to the invention, which is an incubator, on whose incubator chamber wall the evaporator device of Fig. 2 is mounted.

[0088] Fig. 1a shows the evaporator device 1, mounted on the side wall 102 of an incubation chamber 101 of a CC>2 incubator 100 for incubating cell cultures, which is shown in Fig. 5c. The negative z-direction corresponds to the direction of gravity. The evaporator device 1 serves to humidify the incubator atmosphere in the incubation chamber. The evaporator device 1 has an evaporator chamber 2, the bottom section of which contains a heating surface 6 that is in contact with the interior of the evaporator chamber and is thus located in the evaporator chamber 2, and with which water coming into contact with the heating surface can be evaporated. The evaporator device 1 has a first component 21.This includes the evaporator chamber 2, which is manufactured here by turning from a milled component and has a water inlet opening 3 for supplying liquid water into the evaporator chamber and a vapor outlet opening 4 that can be connected to the interior of an incubator chamber of the incubator.

[0089] The water pumping device 5, a microdiaphragm pump with which water can be conveyed to the water inlet opening, is shown in Fig. 2 (but not in Fig. 1a). The water pumping device 5 is connected to the water connection element 15 via the water line 23. The water connection element 15 has a cylindrical outlet section 15a, which is received in a cylindrical receiving chamber 21a of the first component 21, which opens into the water inlet opening 3; thus, both the outlet section 15a and the receiving chamber 21a open into the water inlet opening 3.

[0090] The evaporator device 1 has a water guide 10 with a water guide surface 11, which is formed by an inner wall section 11 of the evaporator chamber. By means of the water guide 10, the water that has entered the evaporator chamber 2 through the water inlet opening 3 is guided along the water guide 10 to the heating surface 6.

[0091] The lower, second component 22, which is connected to the first component 21, contains the heating cartridge 8, which is housed in the heating block 7. A temperature sensor 9 is attached to the heating block 7 for temperature control. The water enters the evaporator chamber 2 via the small throttle orifice 3. The introduced droplet then runs down the wall 11 onto the heated heating block and is evaporated there.

[0092] The water supply system, the pump, is selected and configured here so that a finely controlled pump output delivers a small amount of evaporable water to the heating surface, generating a corresponding amount of steam to regulate the relative humidity (RH value) as precisely and evenly as possible. If large droplets were to form before detaching and evaporating, the explosive evaporation of these droplets could cause smaller droplets to be ejected. Furthermore, there is a greater risk of the RH value in the chamber exceeding the set point. Preliminary tests conducted by the inventors showed that it is advantageous for the droplets to reach the heating surface without falling, particularly by running directly down the wall 11. In this arrangement, the surface tension of the water is overcome sooner, causing the water to flow towards the heating block 7.

[0093] In Fig. 1a, on the left side, is the steam outlet opening 4 into the incubator chamber 101. The steam outlet opening 4 is located above the longitudinal axis A of the steam outlet channel 31. Condensing water in the steam outlet opening 4 is to be conveyed back to the heating block via the sloping bottom wall 32. A gap D is provided between the incubator chamber 101 and the heating cartridge 8 to reduce the transfer of heat to the chamber wall 102. For further thermal protection, insulating material can be inserted into the cavity 104. In addition, plate elements 25 of component 21 / 2T, aligned parallel to the side wall, can be provided there for thermal shielding between the heating block 7 and the side wall 102. Furthermore, both components (housing parts) 21, 22 are made of a material with poor thermal conductivity (here, PEEK plastic).To increase energy efficiency and better insulate against environmental influences, the evaporator is insulated externally by silicone insulating foam components 108, 109. The insulation 108, 109 can be easily removed for repair purposes.

[0094] Fig. 1b shows the evaporator device 1 with modified steam outlet channel 4' and modified housing 2T, mounted on the side wall of an incubation chamber of an incubator, without the water pumping device. The connecting element 30' contains, analogous to the connecting element 30, the steam outlet channel 3T. Its bottom section 32', inclined relative to the horizontal H, leads from the steam outlet opening 4 to the heating surface 6. This forms the bottom section of the evaporator chamber 2.

[0095] Component 2T has a cylindrical receiving chamber 21b' into which the essentially cylindrical engagement section 34' of the connecting element 30' engages in a form-fitting manner. The lateral opening of the receiving chamber 21b' is formed by an optional annular projection 21d', which engages in the opening 105 of the side wall 102 of the incubator chamber 101 and is thus fixed in the zy-plane. The connecting element 30' has the essentially disc-shaped head section 33', which extends parallel to the side wall 102 and perpendicular to the longitudinal axis H of the cylindrical engagement section 34'. To attach the evaporator device 1 to the side wall, the component 2T (or the interconnected components 21 and 22 in Fig. 1a) is inserted into the opening 105 and the connecting element 30' is inserted into the receiving space 21 b' from the inside of the incubator chamber.To finally fix the evaporator device along the (positive) x-axis (in horizontal direction) on the side wall 102, the head section 33' is screwed to the component 2T using holes in the head section 33', the side wall 102 and the component 2T.

[0096] The evaporator chamber 2 is sealed here by means of two O-rings between the engagement section 34' and the receiving chamber 21b'. Similarly, the water connection element 15 is sealed against the receiving chamber 21a of the first component 21 (21') by an O-ring. The engagement of the heating block 7 with the opening 13 in the bottom wall section of the evaporator chamber is also sealed by an O-ring. In this way, the evaporator chamber 2 is essentially only open to the steam outlet opening 4.

[0097] Fig. 2a shows the evaporator device 1 with a connecting element 30" according to a further embodiment of the invention. In conjunction with the detail view in Fig. 2b, the measures that contribute to improving the controlled vapor output of the evaporator device 1 can be readily understood.

[0098] A particularly small water inlet opening 3 (diameter 1.5 mm) allows for fine control of the water inlet.

[0099] The water guide surface 11, arranged vertically (i.e., in the direction of gravity) or perpendicular to the planar central section 6a of the heating surface 6, ensures that minute volumes of water, e.g., 10–20 microliters (preferably corresponding to one pump stroke), flow in a controlled manner along the water guide surface 11 until they come into contact with the edge 6b of the heating surface and evaporate at a temperature of 160–180°C of the heating surface. A Leidenfrost effect can thus be prevented. The water guide surface is preferably arranged such that a volume of water entering the evaporator chamber 2 from the water inlet opening 3 flows along the water guide surface 11 under the influence of gravity. For this to occur, an angle α between the water guide surface 11 and the horizontal is required to initiate the water flow. Preferably, this angle is 80° < α < 180°, and particularly preferably 85° < α < 175°. An “overhang” of the water guidance surface 11 at angles, e.g.80° < a < 90° is possible as long as the water volume adheres sufficiently to the surface, which is the case with more hydrophilic surfaces.

[0100] The water inlet opening 3 is located close to the heating surface: the minimum distance d is 2 mm and is preferably between 20 mm and 0 mm. The flow path I for a volume of water entering the evaporator chamber 2 from the water inlet opening 3 is 1 = 3 mm. Due to the proximity of the heating surface and the heating of the water guide surface 11, the water droplet is also heated as it approaches the heating surface, which is advantageous for the continuous evaporation of the water volume.

[0101] The truncated cone shape of the head of the heating block 7, which projects into the evaporator chamber 2, offers a further advantage with its side section 6b, which is inclined relative to the planar central section 6a. Due to the inclination of the heating surface 6b, a volume of water flowing down the water guide surface 11 is drawn ever closer to it. On the one hand, the water volume is held by adhesion to the water guide surface 11, and on the other hand, it is drawn further towards the heating surface 6b. A descending droplet is thus effectively evaporated in the conically tapered gap between the heating surface 6b and the water guide surface 11 by contact with the heating surface, thereby reducing its diameter, but without losing its adhesion to the water guide surface 11. It can therefore be an effective measure to arrange the water guide surface at an acute angle 5 relative to the heating surface such that the flowing volume of water approaches the apex of the angle 5.Here, too, 5 = -270° applies. The planar central section is optional and can be reduced or omitted in favor of an inclined side section 6b. The truncated cone of the heating block's head section then becomes a cone.

[0102] To prevent condensate water flowing back from the steam outlet channel 31 from reaching the heating surface in irregularly timed and unpredictable volumes, the bottom section of the steam outlet channel 31 has a water return element 16 extending parallel to axis A. This element is spring-mounted by means of a spring 17 to compensate for manufacturing tolerances. The water return element 16 makes physical and thermal contact with the heating surface 6b and is thus also heated. This results in a more regular water return flow and prevents the Leidenfrost effect. The steeper the inclination of the steam outlet channel 31 according to the angle β, the more uniform the water return.

[0103] Fig. 3a shows the evaporator device 1, which includes plate elements 25 of component 21 / 21' that can be aligned parallel to the side wall 102 for thermal shielding between the heating block 7 and the side wall 102. Also shown are the screws 25 with which the connecting element 30 is screwed to component 21 / 21'.

[0104] Fig. 3b shows the evaporator device 1, with first component 21 and second component 22, as well as the temperature sensor 9.

[0105] Figs. 4a to 4e each show an embodiment of the connecting element 30 having the steam outlet channel 31, which can be used to connect the evaporator device 1 according to Figs. 1a to 3b with the side wall 102 of an incubation chamber 101.

[0106] Figures 4a to 4e show various versions of the steam outlet channel 31. Investigations had shown that the geometry of the steam outlet channel can influence both the "spitting behavior" through the steam outlet opening and the control behavior. The shape of the connecting element 30 was designed to prevent as little condensate forming inside as possible from flowing towards the inlet bore, as these droplets can be flung outwards by the overpressure inside the evaporator. Furthermore, large quantities of condensate should never accumulate, which could then surge onto the heating block 7 and subsequently cause "spitting" or an excessive increase in the relative humidity (rH) concentration. The version shown in Figure 4b proved usable with regard to spitting, although relatively speaking, it was the least effective. This also applies, to a lesser extent, to the steam outlet channel 31 shown in Figure 4c. The version shown in Figure 4c...Figure 4a, on the other hand, exhibited good behavior, which was achieved in particular by the slightly upward-shifted bore of the steam outlet opening 4. Furthermore, the partition 33 to the incubator chamber is very thin, which further reduces the risk of the bore 4 becoming clogged. Figure 4d combines several effective measures. Here, the inner contour was also shaped so that the condensate runs away from the opening 4 towards the heating block. Ideally, the angle of the slope should be as steep as possible. Due to the constraints of the installation space, a slope of 4° was achieved here. Figure 4e shows the connecting element from Figure 2a. It has a longitudinal recess in the bottom section of the steam channel 31 to accommodate the pin element 16.

[0107] Fig. 5a shows an incubator 100 with evaporator device 1. The water for the water pump 5 is drawn from a water reservoir 50, which is located above the pump unit 5, here on the top of the housing of the incubator 100.

[0108] Fig. 5b shows a system 200 consisting of a stack of evaporator devices 1 connected to a common water reservoir 50. The water reservoir 50 is located above each pump unit 5, here on the top of the housing of the uppermost incubator 100. The water reservoir 50 is connected to the water supply unit 5 of each of the evaporator devices 1. The system 200 is specifically designed such that, when several of these incubators are in operation, water from this single water reservoir 50 is evaporated by all evaporator devices 2 of these incubators.

[0109] Fig. 5c shows the laboratory device configured as an incubator, with the evaporator device 1 of Fig. 2 mounted on the incubator chamber wall 102. The incubator chamber 101 is closed by the door 111. The housing of the laboratory device is mostly not shown.

Claims

Patent claims 1. Evaporator device (1) for humidifying the incubator atmosphere of an incubator for incubating live cell cultures, comprising an evaporator chamber (2) having a water inlet opening (3) for supplying liquid water into the evaporator chamber and a vapor outlet opening (4) connectable to the interior of an incubator chamber of the incubator, a water conveying device (5) by which water can be conveyed to the water inlet opening, a heating surface (6) arranged in the evaporator chamber and by which water coming into contact with the heating surface can be evaporated, characterized in that the evaporator device (1) has a water guide device (10) by which the water that has entered the evaporator chamber from the water inlet opening (3) can be guided along the water guide device (10) to the heating surface (6).wherein the water guidance device (10) has a water guidance surface (11) formed by a water-bearing element, which is arranged between the water inlet opening and the heating surface (6), so that a gravity-induced water flow along the water guidance surface (11) is enabled.

2. Evaporator device according to claim 1, wherein the evaporator chamber has an inner wall section having this water guide surface.

3. Evaporator device according to one of the preceding claims, wherein the The water guidance device is designed in such a way that the water exiting through the water inlet opening flows on the water guidance surface, in particular without a free water droplet falling onto the heating surface.

4. Evaporator device according to one of the preceding claims, wherein the evaporator device has a water return device by which condensate occurring in the area between the steam outlet opening and the heating surface can be returned along the water return device to the heating surface.

5. Evaporator device according to claim 4, wherein the water return device is in thermal contact with the heating surface.

6. Evaporator device according to claim 4 or 5, wherein the evaporator device has a steam outlet channel extending between the evaporator chamber and the steam outlet opening, wherein the water return device has a water return surface formed in an inner wall of the steam outlet channel and extending between the steam outlet opening and the heating surface.

7. Evaporator device according to any one of the preceding claims 4 to 6, wherein the water return device has a metallic water guide element extending between the steam outlet opening and the heating surface.

8. Evaporator device according to one of the preceding claims, wherein the evaporator device has a vapor outlet channel which extends at least partially along a longitudinal axis, wherein the vapor outlet opening has a smaller opening cross-section than a cross-section of the vapor outlet channel measured perpendicular to the longitudinal axis.

9. Evaporator device according to claim 8, wherein the vapor outlet opening is arranged centrically to the longitudinal axis, wherein the vapor outlet opening is located above the heating surface forming a base and is located above the central longitudinal axis when the evaporator device is mounted on a vertical side wall of an incubator chamber during intended use.

10. Evaporator device according to one of the preceding claims, wherein the water conveying device is characterized by at least one of the following technical specifications: a) the water conveying volume is between 1 pl and 50 pl, preferably between 5 pl and 20 pl, preferably between 10 pl and 20 pl, preferably between 7 pl and 15 pl, preferably between 9 pl and 11 pl; b) the minimum water conveying rate is between 0.5 pl / h and 100 pl / h, preferably between 0.5 pl / h and 20 pl / h, preferably between 0.5 pl / h and 10 pl / h.

11. Evaporator device according to one of the preceding claims, comprising an electronic control device configured to operate the water conveying device and the heating surface for controlling the humidity in an incubator chamber connectable to the steam outlet opening.

12. Evaporator device according to one of the preceding claims, comprising a water supply channel which opens into the water inlet opening, wherein an opening cross-section of the water inlet opening is smaller than an opening cross-section of the water supply channel.

13. Laboratory device for incubating samples in an incubation chamber, in particular an incubator for incubating live cell cultures, comprising an evaporator device according to one of the preceding claims.

14. Method for generating water vapor for humidifying the atmosphere in an incubation chamber of a laboratory device, in particular an incubator for incubating live cell cultures, by means of an evaporator device having a heating surface, in particular the evaporator device according to any one of claims 1 to 12, wherein water is supplied to the incubator by means of a water supply device. The water flow is directed along the heating surface, where the water evaporates.

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