Culture apparatus

A culture apparatus which is capable of shortening sterilization time includes a gas concentration measuring sensor, pipes connected to a gas concentration measuring device and every corner of a cultivating chamber, and a sterilizing gas generator that supplies sterilizing gas into a cultivating chamber and atomizes a sterilizer solution (oxygenated water) by means of an ultrasonic vibrator. The culture apparatus further includes an ultraviolet lamp that irradiates gas in the cultivating chamber, a freely opening/closing door, a door-locking device, and a controller for controlling the locking device to prevent the door from being opened from start of the sterilization process to end of the decomposition process.

BACKGROUND OF THE INVENTION

This invention relates to a culture apparatus for cultivating (or incubating) cultures such as cells, microbes and the like in a cultivating chamber.

A culture apparatus, which has been conventionally called an incubator, cultivates cultures (samples) such as cells, microbes and the like as culture targets in an aseptic cultivating chamber while keeping temperature of the cultivating chamber and gas concentration of carbon dioxide (CO2), Oxygen (O2) or the like constant. As shown inFIG. 4, a culture apparatus100includes an insulating box body102comprising an outer metal box110having an opening102A at one side thereof and an inner stainless box116provided inside the outer box110. In addition, a cultivating chamber104is formed in a space (inner box116) surrounded by a door (inner door118) blocking the opening102A in a free-opening/closing manner. The cultivating chamber104is vertically partitioned by a plurality of shelves106on which vessels108that contain cultures are placed.

The culture apparatus100is provided with an air circulation fan128for controlling circumferences in the cultivating chamber104, which is arranged in a duct124, and a gas concentration measuring device130having a gas concentration measuring sensor for carbon dioxide or oxygen (not shown). The gas concentration measuring device130communicates to the cultivating chamber104via pipes134and136for guiding gas in the cultivating chamber104to the gas concentration measuring sensor. An ultraviolet lamp150, which is arranged within the cultivating chamber104, irradiates the cultivating chamber104with an ultraviolet ray to sterilize circulating air, and gas is gathered from a measuring hole138stopped by a rubber stopper140for the purpose of measuring gas concentration in the cultivating chamber104.

The insulating box body102is provided with an outer door114for blocking the opening102A in a free-opening/closing manner, and the cultures are sent in and drawn out of the cultivating chamber104by opening/closing of the outer door114and the inner door118. An insulating material112for heat conservation is provided inside the outer box110, and a circulation path120of air or water is formed between the inner box116and the outer box110. A heater122is arranged in the circulation path120. Heat generated from the heater122is transferred to the cultivating chamber104by thermal conduction to the inner box116and heat transfer from the circulation path120by air or water to keep the cultivating chamber104at a temperature appropriate for cultivation. This allows the cultures, such as cells, microbes and the like, to be cultivated in the cultivating chamber104(see Japanese Patent Application Publication No. 2005-118021).

Such a culture apparatus100should be used while keeping the cultivating chamber104clean at all times. However, if cultivated cells or microbes are infected with bacteria, virus or the like, the cultivating chamber104and air in the cultivating chamber104of the culture apparatus are contaminated. Thus, in order to keep the cultivating chamber104clean, the cultivating chamber104is swept clean or is sterilized by being heated at a high temperature of more than 90° C. with a heater (not shown).

As described above, in the prior art, in order to keep the cultivating chamber clean, the cultivating chamber104has to be swept clean or be sterilized by being heated at a high temperature of more than 90° C. with a heater. However, this technique could not thoroughly sterilize the culture apparatus including the gas concentration measuring sensor, the pipes connected to the gas concentration measuring device and every corner of the cultivating chamber.

In addition, heat-resistant germs are incompletely sterilize even at the high temperature of more than 90° C., and further, about 8 hours are required to restart the cultivation through a cooling process from the increase of temperature of the cultivating chamber for sterilization by heating. This may lead to a problem of too much time during which the culture apparatus can not be used for cultivation.

SUMMARY OF THE INVENTION

The present invention has made to overcome such a problem and it is an object of the invention to provide a culture apparatus which is capable of shortening a sterilization time and sterilizing the culture apparatus including a gas concentration measuring sensor, pipes connected to a gas concentration measuring device and every corner of a cultivating chamber.

According to a first aspect of the invention, there is provided a culture apparatus for cultivating cultures such as cells, microbes or the like in a cultivating chamber, including a sterilizing gas generator that supplies sterilizing gas into the cultivating chamber.

According to a second aspect of the invention, in the first aspect, the sterilizing gas generator atomizes a sterilizer solution by means of an ultrasonic vibrator.

According to a third aspect of the invention, in the first aspect, the sterilizing gas generator evaporates a sterilizer solution by dipping an absorbing member into the sterilizer solution.

According to a fourth aspect of the invention, in one of the first to third aspects, the sterilizing gas concentration in the cultivating chamber is from 0.1 ppm to 100 ppm.

According to a fifth aspect of the invention, in one of the first to fourth aspects, the culture apparatus further includes an ultraviolet generator that irradiates gas in the cultivating chamber with an ultraviolet ray.

According to a sixth aspect of the invention, in the fifth aspect, the culture apparatus further includes a controller that performs a sterilization process for filling the cultivating chamber with the sterilizing gas for a predetermined period of time and a decomposition process for decomposing the sterilizing gas by irradiating the gas in the cultivating chamber with the ultraviolet ray by means of the ultraviolet generator.

According to a seventh aspect of the invention, in the sixth aspect, the culture apparatus further includes a door for blocking an opening of the cultivating chamber in a free-opening/closing manner and a locking device for prohibiting the door from being opened, and the controller controls the locking device to prevent the door from being opened from start of the sterilization process to end of the decomposition process.

According to the first aspect of the invention, since the culture apparatus for cultivating cultures such as cells, microbes or the like in the cultivating chamber, includes the sterilizing gas generator that supplies sterilizing gas into the cultivating chamber, it is possible to eradicate sundry germs inside the apparatus including the cultivating chamber before or after the cultivation operation. Accordingly, it is possible to realize a smooth cultivation operation in the cultivating chamber.

According to the second aspect of the invention, in the first aspect, since the sterilizing gas generator atomizes the sterilizer solution by means of the ultrasonic vibrator, it is possible to atomize a sundry germs sterilizer and fill the cultivating chamber with the atomized sterilizer as a gas without decomposing the sterilizer, unlike a heat and atomization method. Accordingly, it is possible to efficiently sterilize the inside of the apparatus.

According to the third aspect of the invention, in the first aspect, since the sterilizing gas generator evaporates the sterilizer solution by dipping the absorbing member into the sterilizer solution, it is possible to effectively generate the sterilizing gas to sterilize the inside of the apparatus while simplifying the configuration of the apparatus.

According to the fourth aspect of the invention, in one of the first to third aspects, since the sterilizing gas concentration in the cultivating chamber is from 0.1 ppm to 100 ppm, it is possible to reliably sterilize the inside of the apparatus.

According to the fifth aspect of the invention, in one of the first to fourth aspects, since the culture apparatus further includes the ultraviolet generator that irradiates gas in the cultivating chamber with the ultraviolet ray, it is possible to quickly lower the concentration of the sterilizing gas to a concentration harmless to a human body after sterilizing the inside of the apparatus with the sterilizing gas. Accordingly, it is possible to reduce wait time until the next cultivation operation starts.

According to the sixth aspect of the invention, in the fifth aspect, since the culture apparatus further includes the controller that performs the sterilization process for filling the cultivating chamber with the sterilizing gas for the predetermined period of time and the decomposition process for decomposing the sterilizing gas by irradiating the gas in the cultivating chamber with the ultraviolet ray by means of the ultraviolet generator, it is possible to automate operation from the sterilization of the inside of the apparatus with the sterilizing gas to the decomposition of the sterilizing gas, thereby remarkably improving workability.

According to the seventh aspect of the invention, in the sixth aspect, since the culture apparatus further includes the door for blocking the opening of the cultivating chamber in the free-opening/closing manner and the locking device for prohibiting the door from being opened, and the controller controls the locking device to prevent the door from being opened from start of the sterilization process to end of the decomposition process, it is possible to prevent the door from being opened by mistake before the sterilizing gas concentration is lowered to a valve harmless to a human body by the ultraviolet ray after the inside of the apparatus is sterilized with the sterilizing gas, thereby securing safety of the apparatus.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The most important feature of the present invention is to sterilize every corner of a cultivating chamber thoroughly and shorten time taken from sterilizing start to sterilizing end for the cultivating chamber. The purpose of sterilizing every corner of the cultivating chamber thoroughly and shortening time taken from the sterilizing start to the sterilizing end for the cultivating chamber can be accomplished by a simple configuration that a sterilizing gas generator is merely provided within the cultivating chamber.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.FIG. 1is an end side view showing a structure of a culture apparatus1according to an embodiment of the present invention, andFIG. 2is a block diagram of a control circuit for controlling the culture apparatus1of the present invention.

In this embodiment, as shown inFIG. 1, the culture apparatus1includes an insulating box body2comprising an outer metal box10having an opening2A at one side thereof and an inner stainless box16. In addition, the opening2A of the inner box16is provided with a transparent inner door18whose right side is supported to the insulating box body2by a hinge in a free-opening/closing manner. The inner door18blocks the opening2A air-tightly by means of a gasket (not shown) provided in the opening2A of the insulating box body2.

A cultivating chamber4is formed in a space (inner box16) surrounded by an inner door18blocking the opening2A in a free-opening/closing manner. Within the cultivating chamber4A are provided a plurality (2 in this embodiment) of shelves6that vertically partitions the cultivating chamber4. Cultures received in the cultivating chamber4are sent in and drawn out of the cultivating chamber4by opening/closing of an outer door14and the inner door18. In addition, vessels (not shown) that contain the cultures are placed on the shelves6.

An insulating material12for heat conservation is provided inside the outer box10, and a circulation path20of air or water is formed between the inner box16and the outer box10. A heater22is arranged in the circulation path20(in the lower side of the cultivating chamber4). When the heater22is heated, heat generated from the heater22is transferred to the cultivating chamber4by thermal conduction to the inner box16and heat transfer from the circulation path20by air or water to keep the cultivating chamber4at a temperature appropriate for cultivation.

In addition, a rear wall23is provided in the rear side of the cultivating chamber4and a duct24is provided between the rear wall23and the inner box16. An inlet26communicating to the cultivating chamber4is provided in the upper side of the duct24and an outlet27is provided in the lower side of the duct24. In addition, an air circulation fan28for controlling circumferences in the cultivating chamber4is arranged inside the duct24at a position corresponding to the inlet26. Air in the cultivation chamber4is absorbed through the inlet26into the duct24by means of the fan28, and the absorbed air is discharged through the outlet27at the lower side of the duct24into the cultivating chamber4(as indicated by arrows inFIG. 1). Such a configuration allows the air to be forcedly circulated in the cultivating chamber4.

In addition, the culture apparatus1is provided with a gas concentration measuring device30having a gas concentration measuring sensor32(shown inFIG. 2) therein to measure the concentration of carbon dioxide (CO2) or oxygen (O2) supplied into the cultivating chamber4, and an oxygenated water measuring sensor39to measure oxygenated water gas in the cultivating chamber4. The gas concentration measuring device30communicates to the cultivating chamber4via two pipes34and36to guide gas in the cultivating chamber4(and in the duct24) to the gas concentration measuring sensor32. In addition, a fan33(shown inFIG. 2) for absorbing the gas in the cultivating chamber4into the gas concentration measuring device30to measure gas concentration and then returning the gas to the duct24is connected to the gas concentration measuring device30.

In more detail, the gas concentration measuring sensor32is configured to detect the gas concentration in the cultivating chamber4by absorbing the gas in the duct24(in the cultivating chamber4) via one pipe34and discharging the absorbed gas into the duct24via the other pipe36. In addition, the culture apparatus1is provided with a measuring hole38stopped by a rubber stopper40in order to measure the gas concentration in the cultivating chamber4. When the rubber stopper40of the measuring hole38is unplugged by an operator, the concentration and components of the gas in the cultivating chamber4can be examined.

The culture apparatus1is connected by a pipe with a carbon dioxide supply device, an oxygen supply device (not shown) or the like to supply cultivation gas such as carbon dioxide or oxygen gas into the cultivating chamber4. In addition, inside the cultivating chamber4is provided a sterilizing gas generator42to atomize oxygenated water (corresponding to a sterilizer solution in the present invention).

For example, the sterilizing gas generator42generates gas by atomizing the oxygenated water as the sterilizer solution in the cultivating chamber4by means of an ultrasonic wave. The sterilizing gas generator42includes a stainless vessel44(typically called a butt) provided in the bottom of the inner box16and an ultrasonic vibrator46. In addition, an electronic valve66(shown inFIG. 2) to control the amount of supply of carbon dioxide gas, oxygen gas and sterilizing gas by its opening/closing is provided the pipe connected to the carbon dioxide supply device or the oxygen supply device.

The vessel44has its top side opened, has a size as large as to accommodate the predetermined amount of oxygenated water, and is provided near the front (in the cultivating chamber4) of the outlet27of the duct24. In addition, the bottom of the vessel44is depressed into the circulation path20by a predetermined dimension and the ultrasonic vibrator46is provided within the depressed vessel44. Hydrogen peroxide gas (corresponding to the sterilizing gas in the present invention) as a sterilizer is supplied by a predetermined amount by an operator. When the oxygenated water is evaporated by a heating type humidifier which is currently frequently being used, since hydrogen peroxide (sterilizer) is decomposed, the ultrasonic vibrator46is attached to an outer side (in the circulation path20) of the bottom of the cultivating chamber4in the present invention. The ultrasonic vibrator46can atomize the hydrogen peroxide without heating it. Since a technique for the ultrasonic vibrator46to atomize the hydrogen peroxide at a low temperature is well known in the art, explanation of which will be omitted.

An ultraviolet lamp50(corresponding to an ultraviolet generator in the present invention) for generating an ultraviolet ray is arranged in the culture apparatus1. The ultraviolet ray emitted from the ultraviolet lamp50decomposes the sterilizing gas circulating in the duct24, thereby making it harmless. To make the sterilizing gas harmless by the ultraviolet lamp50will be described in detail later.

When the oxygenated water is atomized and gasified by the ultrasonic wave to sterilize the cultivating chamber4in the culture apparatus1, if the outer door14is carelessly opened, the sterilizing gas is get out of the cultivating chamber4, which may result in danger to a human body. So, in the present invention, the culture apparatus1includes a locking device52to prevent the outer door from being released while the cultivating chamber4is sterilized with the oxygenated water. The locking device52is provided in the top side of the insulating box body2and between the outer box10and the outer door14. The locking device52is fixed to the outer box10, and in this state, the outer door14is configured to be openable/closable and the outer door14is configured to be locked/unlocked with the locking device52.

In the meantime, as shown inFIG. 2, the culture apparatus1is provided with a controller60. The controller60is, for example, a general-purpose microcomputer including a storing unit (memory) in which various data can be stored, a timer, etc. The controller60is connected with an operation switch62such as a power switch or a sterilization start switch (not shown), the gas concentration measuring sensor32provided in the gas concentration measuring device30, a temperature sensor64for detecting the internal temperature of the cultivating chamber4, an oxygenated water measuring sensor39, etc.

In addition, the controller60is connected with a plurality of electronic valves66provided in pipes of the carbon dioxide gas supply device or the oxygen gas supply device, the ultraviolet lamp50for sterilization of circulation air, the air circulation fan28for controlling the circumferences in the cultivating chamber4, etc. In addition, the controller60is connected with the heater22for heating the cultivating chamber4at a temperature appropriate for cultivation, the ultrasonic vibrator46for atomizing the oxygenated water, the locking device52for preventing the outer door14from being released.

The controller60has programs for a sterilization process for sterilizing the cultivation chamber4and a decomposition process for decomposing the sterilizing gas in the cultivating chamber4with the ultraviolet lamp50after the sterilization process, which are stored in the memory of the microcomputer.

Next, with the above configuration, the operation of the culture apparatus1will be described. In particular, in this embodiment, the sterilization process and the decomposition process of the culture apparatus1will be described. In the sterilization process of the culture apparatus1, first, when the operation switch62(the sterilization start switch) is pushed by an operator, the controller60drives the locking device52to lock the outer door14and drives the fan28. Accordingly, the air in the cultivating chamber4is absorbed into the duct24through the inlet26and is discharged into the cultivating chamber4from the bottom of the duct24, circulating in the cultivating chamber4(see arrows indicated inFIG. 1).

The controller60opens the electronic valves66provided in the pipes and operates the fan33. In addition, the controller60heats the heater, detects the temperature of the cultivating chamber4by means of the temperature sensor64, and keeps the cultivating chamber4at a predetermined temperature (cultivation temperature in this case). Moreover, the controller60automatically interrupts the heat from the heater22after the decomposition process.

Next, the controller60drives the ultrasonic vibrator46with a preset timer for a predetermined period of time to atomize the oxygenated water in the vessel44and scatter the atomized oxygenated water into the cultivating chamber4. As the cultivating chamber4is heated with the heater22at the predetermined temperature, the oxygenated water atomized and scattered into the cultivating chamber4is evaporated in a short time to be hydrogen peroxide gas with which the cultivating chamber4is filled. At this time, since the vessel44is filled with a predetermined amount of oxygenated water, the cultivating chamber4has hydrogen peroxide gas concentration of from 0.1 ppm to 100 ppm. The amount of oxygenated water in the vessel44is beforehand obtained by experiment such that the hydrogen peroxide gas concentration in the cultivating chamber4is from 0.1 to 100 ppm.

While the cultivating chamber4is sterilized with the hydrogen peroxide gas circulating by the fan28, the gas in the duct24is absorbed into the gas concentration measuring device30through the pipe34by the fan33and then is returned to the duct24through the pipe36. Accordingly, every corner of the cultivating chamber4, the gas concentration measuring device30and the pipes34and36, that is, all the inside of the culture apparatus1including the cultivating chamber4, can be sterilized with efficiency.

In addition, since the oxygenated water supplied and stored in the vessel44is atomized and then evaporated, the inside of the culture apparatus1can be reliably sterilized with efficiency. In addition, since the ultrasonic vibrator46to atomize the oxygenated water does not heat and evaporate the oxygenated water, it is possible to atomize oxygenated water without decomposing a sundry germs sterilizer, unlike the heat and atomization.

After performing the sterilization process for a predetermined period of time, the controller60stops the ultrasonic vibrator46and turns on the ultraviolet lamp50provided in the duct24for transfer to the decomposition process. The controller60performs the sterilization process and the decomposition process in an automatic sequential manner. In the decomposition process, since the controller60operates the fans28and33and so on and turns on the ultraviolet lamp50, the hydrogen peroxide gas inside the culture apparatus1is circulated to the ultraviolet lamp50and is decomposed by irradiation of the ultraviolet lamp50. According to a decomposition reaction of the hydrogen peroxide, H2O2→OH radicals→H2O, the hydrogen peroxide finally turns to harmless water.

The controller60continues to perform the decomposition process for the hydrogen peroxide gas by the ultraviolet ray from the ultraviolet lamp50until the concentration of the hydrogen peroxide gas in the cultivating chamber4, which is detected by the oxygenated water measuring sensor39, is lowered to a secure value to a human body. Accordingly, since the concentration of the hydrogen peroxide gas in the culture apparatus1can be quickly lowered to a value harmless to a human body, it is possible to significantly reduce wait time until the next cultivation operation starts.

When the decomposition process is completed, the controller60drives the locking device52to release the lock of the outer door14. In this case, as the hydrogen peroxide gas (sterilizing gas) in the cultivating chamber4is forcedly decomposed with the ultraviolet ray, it is possible to significantly shorten the wait time till the next cultivation operation. Accordingly, it is possible to eradicate sundry germs inside the apparatus including the cultivating chamber4before or after the cultivation operation, thereby realizing a smooth cultivation operation in the cultivating chamber4.

In addition, until the decomposition process is ended from the sterilization process in the culture apparatus1, the controller60prohibits the outer door14from being opened by means of the locking device52. Accordingly, it is possible to prevent the outer door14from being opened by mistake before the sterilizing gas concentration is lowered to a value harmless to a human body by the ultraviolet ray after the inside of the culture apparatus1is sterilized with the sterilizing gas. Thus, when the cultivating chamber4is sterilized with the sterilizing gas, it is possible to secure substantial safety of the culture apparatus1.

Next,FIG. 3shows a culture apparatus1according to another embodiment of the present invention. The culture apparatus1of this embodiment has substantially the same configuration as the above-described embodiment. Hereinafter, only portions different from the above-described embodiment will be described. In the figure, the same elements as the above-described embodiment are denoted by the same reference numerals, and explanation of which will be omitted. As shown inFIG. 3, in the culture apparatus1, the ultrasonic vibrator46of the sterilizing gas generator42in Embodiment1is replaced with an absorbing member56. When the absorbing member56is dipped into oxygenated water, the oxygenated water is evaporated.

That is, the sterilizing gas generator42is provided with the absorbing member56erecting in the vessel44having flat bottom. A frame (not shown) made of stainless steel or synthetic resin is provided around the absorbing member56. A given wide nonwoven fabric or the like to suck up the oxygenated water according to a capillary effect is fixed in the frame.

In more detail, the vessel44is provided near the front side (in the cultivating chamber4) of the outlet27as described above, and the frame attached with the absorbing member56is erected and fixed in the bottom of the vessel44. With this configuration, air discharged from the duct24through the outlet27makes direct contact with the absorbing member56and the oxygenated water is evaporated from the absorbing member56to properly sterilize the cultivating chamber4. In addition, the hydrogen peroxide gas concentration in the cultivating chamber4is measured using a hydrogen peroxide measuring test paper put in the cultivating chamber4.

In this manner, in the sterilizing gas generator42, the absorbing member56is dipped into the oxygenated water, and circulating air contacts the absorbing member56for a predetermined period of time set by a timer controlled by the controller60. Thus, the oxygenated water is evaporated and the cultivating chamber4is filled with the evaporated oxygenated water. Accordingly, it is possible to effectively generate the sterilizing gas to sterilize the inside of the culture apparatus1. In particular, since the absorbing member56has only to be erected in the vessel44filled with the oxygenated water, it is possible to significantly simplify the sterilizing gas generator42.

Although it has been illustrated in the above embodiments that the sterilizing gas generator42is provided within the cultivating chamber4of the culture apparatus1, without being limited to this, the sterilizing gas generator42may be provided outside the culture apparatus1instead of inside the cultivating chamber4. In addition, although the hydrogen peroxide has been used as the sterilizer, without being limited to the hydrogen peroxide, the sterilizer may be of any type as long as it can have sterilizing power.

The present invention is not limited to the above-described embodiments but may be effectively changed and modified in various ways without departing from the spirit and scope of the invention.