JPH0710232Y2 - Freeze dryer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Field of Industrial Application) This invention relates to a freeze-drying apparatus.

(Prior Art) In general, freeze-drying is a well-established drying method whereby, for example, drugs such as vaccines, vitamin preparations and constituent substances are dried and stored. The water-soluble product undergoing drying is initially frozen and then placed under vacuum by a vacuum device. Under such a condition, the water content of the product directly changes from ice to steam without passing through an intermediate liquid stage. Since a large amount of this sublimation steam adversely affects the vacuum device, it has a structure in which it is collected by the adsorbent filled in the condenser main body.

(Problems to be Solved by the Invention) As described above, the sample before drying is in a frozen state, and it becomes difficult to stabilize the product when thawing begins, and therefore it is necessary to rapidly dry the sample in the frozen state. Therefore, a constant vacuum state is always maintained during the operation of the drying device.

However, when frozen samples are sequentially added to the dry chamber and continuous operation is performed, the degree of vacuum decreases when frozen samples are added. Alternatively, when the adsorbent in the condenser main body collects moisture and reaches a saturated state, the second condenser is switched to the standby state, but the vacuum degree is lowered even at this time. To do. In particular, since the adsorption passage is filled with the adsorbent, it takes time to recover to the specified vacuum degree due to this resistance, and there is a possibility that the frozen sample may be melted in some cases.

Then, this invention aims at providing the freeze-drying apparatus which can be quickly recovered, when a vacuum degree falls.

[Means for Solving the Problems] (Means for Solving the Problems) In order to achieve the above-mentioned object, the present invention relates to a condenser main body having an adsorption passage for adsorbing water, which communicates with the starting end side of the adsorption passage and is frozen. The dry chamber in which the sample is set and the vacuum pump communicating with the end side of the adsorption passage are connected to form a circuit from the dry chamber to the condenser body and the vacuum pump, and the degree of vacuum in the circuit is set in this circuit. A vacuum detection sensor for detecting is provided with a bypass circuit in which one end communicates with a start end side and a termination end side of the adsorption passage and the other end directly communicates with a vacuum pump. An on-off valve is provided that is controlled to open and close based on the detection signal of.

(Operation) According to such a freeze-drying apparatus, the vacuum detection sensor outputs a detection signal corresponding to the degree of vacuum in the circuit, and the open / close valve is controlled to the open state or the closed state based on the detection signal. When the on-off valve is in the open state, the bypass circuit passing through a part of the adsorption passage works, so that the large resistance of the adsorption passage is not received, the degree of vacuum is quickly restored to the original state, and the frozen sample does not melt.

(Embodiment) An embodiment of the present invention will be described in detail below with reference to the drawings of FIG. 1 and FIG.

In the figure, 1 indicates a dry chamber in which a plurality of frozen samples 3 can be set, and 5 indicates a vacuum pump, respectively. In a circuit 7 connecting the dry chamber 1 and the vacuum pump 5, a pair of left and right condensers 9 and 9 are arranged. One of the condensers 9 is for standby.

The dry chamber 1 is connected and communicated with a starting end portion 13 of an adsorption passage 11 provided in the condenser body 9a, and a circuit 7 connecting the dry chamber 1 and the condenser body 9a is provided with a _first opening / closing valve V _1. ing. The vacuum pump 5 is the end portion of the adsorption passage 11.
A second opening / closing valve V ₂ is provided in the circuit 7 that connects and communicates with the condenser main body 9a and the vacuum pump 5, and the standby circuit 7 is also provided with the first and second opening / closing valves V ₁ V ₂ is provided for each. The condenser main body 9a is formed in a cylindrical shape, and the upper part is closed by an upper lid 17 and the lower part is closed by a lower lid 19.

In the condenser body 9a, an adsorbent 21 such as a molecular sieve is doubly arranged and set via a cylindrical partition wall 23, and the adsorption passage 11 flowing from the outside to the inside is continuously formed.

The outer side 11a of the adsorption passage 11 has a predetermined distance a between the adsorption layer having the adsorbent 21 and the partition wall 23 and the inner surface of the condenser body 9a.
Is made, and it is possible to pass without receiving great resistance. The inside 11b of the adsorption passage 11 is filled with the adsorbent 21 in a dense state.

Further, a heating element 25 made of a material such as nichrome wire or ceramic is provided in the condenser body 9a, and is connected to a power source (neither is shown) via a control unit.

Moreover, the condenser in the exhaust pipe 27 extending from the upper lid 17 of the main body 9a, a third on-off valve V ₃ is provided to be opened to the atmosphere, the third on-off valve V ₃ to the discharge pipe 27 for standby Is provided.

The first, second and third on-off valves V ₁ , V ₂ , V ₃ are electrically connected to a control unit (not shown) that controls the heating element 25,
When the first and second on-off valves V ₁ and V ₂ are open, that is, during freeze-drying operation, the third on-off valve V ₃ is closed and the heating element 25 is off. Further, when the first and second on-off valves V ₁ and V ₂ are closed, that is, the steam in the condenser body 9a is released to the outside, and the third on-off valve V ₃ is opened during the regeneration operation, The heating element 25 comes to be controlled in the ON state.

In addition, when switching to standby, the first, second, and third standby
The on-off valves V ₁ , V ₂ , V ₃ and the heating element (not shown) are also controlled in the same manner. The first and second on-off valves V ₁ for standby
・ V ₂ is opened and the third on-off valve V ₃ is controlled to be closed.

On the other hand, in the circuit 7 from the dry chamber 1 to the vacuum pump 5, a bypass circuit 29 passing through the outside 11a of the adsorption passage 11 is provided.
Is provided.

That is, one end of the bypass circuit 29 is connected to the exhaust pipe 27, and the other end is connected to the vacuum pump 5 via the second on-off valve V ₂ .

The bypass circuit 29 is provided with a _fourth opening / closing valve V 4
The on-off valve V ₄ is controlled to be in an open state or a closed state based on a detection signal from a vacuum detection sensor 31 provided in the circuit 7. The valve V ₄ comes to be controlled from the closed state to the open state.

The fourth on-off valve V ₄ is provided to be opened and closed freely controlled based on the detection signal from the vacuum sensor 31 to the bypass circuit 29 to be a stand-off valve V ₄ of the fourth stand When it is switched to the use mode, the control is similarly performed based on the signal from the vacuum detection sensor 31.

In the freeze-drying apparatus configured as described above, during the freeze-drying operation, the first and second on-off valves V ₁ and V ₂ are in the open state, and the chamber 1 is frozen by being vacuumed by the vacuum pump 5. Drying is performed. In this case, chamber 1
The sublimation steam generated inside is collected when passing through the adsorption passage 11.

Next, when the adsorbent 21 reaches the saturated state and switches to the standby state when the frozen sample 3 is added or during the freeze-drying operation, the degree of vacuum in the circuit 7 decreases, and when the vacuum detection sensor 31 detects it. The fourth on-off valve V ₄ is opened. As a result, the bypass circuit 29 passing through the outer side 11a of the adsorption passage 11 works, so that a large resistance is not received and the degree of vacuum is rapidly recovered. Since the vapor is adsorbed when passing through the outside 11a of the adsorption passage 11, the vacuum pump 5 is not adversely affected.

[Effect of the Invention] As described above, according to the freeze-drying apparatus of the present invention, even if the vacuum degree of the circuit is lowered, the vacuum degree in the circuit can be rapidly restored by the bypass circuit passing through a part of the adsorption passage. In addition, the vacuum pump is not adversely affected.

[Brief description of drawings]

FIG. 1 is an overall schematic explanatory view showing a freeze-drying device of the present invention, and FIG. 2 is a sectional view of a main part. 1 …… Dry chamber 3 …… Frozen sample 5 …… Vacuum pump 7 …… Circuit 9 …… Condenser body 11 …… Adsorption passage 29 …… Bypass circuit 31 …… Vacuum detection sensor V ₄ …… Open / close valve

Claims (1)

[Scope of utility model registration request] 1. A condenser main body having an adsorption passage for adsorbing moisture, a dry chamber communicating with the starting end side of the adsorption passage and having a frozen sample set therein, and a vacuum pump communicating with the ending end side of the adsorption passage. Connected to form a circuit from the dry chamber to the condenser body and vacuum pump, and in this circuit, a vacuum detection sensor that detects the degree of vacuum in the circuit,
A bypass circuit is provided, one end of which is connected between the start side and the end side of the adsorption passage and the other end of which is directly connected to the vacuum pump. The bypass circuit is opened / closed based on a detection signal from the vacuum detection sensor. A freeze-drying device having an on-off valve that can be freely controlled.