JP2001317498A - Vapor ejector provided with drain discharge means - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent drain from collecting in an vapor ejector, and prevent the drain from flowing backward to a vacuum tank. SOLUTION: In this vapor ejector 1 being composed of a vapor nozzle 3 arranged in a suction chamber 2 and a diffuser 4 connected to a suction chamber side surface end reducing pressure in the vacuum tank 10 by injecting vapor toward the diffuser 4 from the vapor nozzle 3 by connecting the suction chamber to the vacuum chamber 10 via an air suction pipe 11, a drain discharge port 6 is arranged in a bottom part of the suction chamber 2. A drain discharge pipe 7 is connected to a drain discharge port 6. A drain discharge valve 8 is arranged in the drain discharge pipe 7. When vapor is not injected from the vapor nozzle 3, the drain discharge valve 8 is opened, and the drain in the vapor ejector 1 is discharged.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a steam ejector provided with a drain discharge means.

[0002]

2. Description of the Related Art A steam nozzle is provided in a suction chamber and a diffuser connected to a side of the suction chamber. By injecting steam from the steam nozzle toward the diffuser, air in the suction chamber is discharged and connected to the suction chamber. Steam ejectors that decompress the inside of a vacuum chamber are widely used. When the decompression operation is performed by the steam injection, the moisture contained in the sucked air and the moisture of the injected steam are condensed, and depending on the installation state of the steam ejector, the drain may accumulate in the suction chamber of the steam ejector. Even if the amount of drain that accumulates in the steam ejector in a single decompression operation is small, if the drain accumulates in the steam ejector by repeating the decompression operation and the amount of drain in the steam ejector increases, the drain is discharged from the steam ejector to the air Since it is conceivable that the gas flows backward through the suction pipe, it is necessary to prevent the drain from flowing backward.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to prevent the drain from accumulating in the steam ejector and prevent the drain from flowing back into the vacuum chamber.

[0004]

According to the first aspect of the present invention, the suction chamber comprises a steam nozzle provided in the suction chamber and a diffuser connected to the side of the suction chamber, and the suction chamber is connected to the vacuum chamber by an air suction pipe. In the steam ejector that depressurizes the inside of the vacuum chamber by injecting steam from the steam nozzle to the diffuser, a drain outlet is provided at the bottom of the suction chamber, a drain outlet is connected to the drain outlet, and a drain outlet is connected to the drain outlet. A drain discharge valve is provided, and when the steam is not being injected from the steam nozzle, the drain discharge valve is opened to discharge the drain in the steam ejector.

[0005] In the case of claim 2, in addition to the steam ejector provided with the drain discharge port, a vacuum generating device which operates prior to the steam ejector is provided. This is a multi-stage vacuum generating system in which a steam ejector provided with a discharge port is operated, wherein a drain discharge pipe connected to a drain discharge port of the steam ejector has the other end connected to a preceding vacuum generating device. The pre-vacuum generator is operating, and in the steam ejector with the drain discharge port, the drain discharge valve is opened when not operating, and the drain in the steam ejector is sucked and discharged by the pre-vacuum generator. I do.

In the case of the third aspect, the drain discharge valve is a check valve which opens only when the action of discharging from the steam ejector is applied, and does not open when the action of suctioning to the steam ejector is applied.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a flowchart of a vacuum cooling device provided with a steam ejector embodying the present invention, and FIG. 2 is a flowchart of a vacuum cooling device according to another embodiment of the present invention.
In the present embodiment, a steam ejector is used as a vacuum generator of a vacuum cooling device that cools food by evaporating moisture in the food by depressurizing the inside of the vacuum tank 10 containing the food, and removing heat of vaporization. I have.

An air suction pipe 11 for discharging air from the vacuum chamber 10 is connected to the vacuum chamber 10.
The inside of the vacuum chamber 10 is depressurized by the vacuum generator provided in the above. FIG. 1 shows a case in which one steam ejector 1 and one water ejector 9 are provided as vacuum generators, and FIG. 2 shows a case in which a multistage steam ejector comprising two steam ejectors 1 and a water ejector 9 are provided. In these cases, since the water ejector 9 is operated first, the water ejector 9 becomes a preceding vacuum generating device.

First, a description will be given with reference to FIG. The steam ejector 1 and the water ejector 9 are connected in series, and in order to reduce the size of the apparatus, the steam ejector 1 is installed horizontally so as to inject steam horizontally. The water ejector 9 is connected to a circulating water tank for storing circulating water, and is provided with a circulating pipe and a circulating pump 14 for sending circulating water in the circulating water tank to the water ejector 9. The steam ejector 1 has a shape in which a steam nozzle 3 is provided in a cylindrical suction chamber 2, and a diffuser 4 is connected to a side surface of the suction chamber 2. A steam supply pipe is connected to the steam nozzle 3, and the steam is injected from the steam nozzle 3 to the diffuser 4 by opening a steam supply control valve 13 provided in the steam supply pipe.

The steam nozzle 3 and the diffuser 4 are respectively arranged on opposing planes of the cylindrical suction chamber 2, and an inlet 5 and a drain outlet 6 are provided on the peripheral wall of the cylindrical suction chamber 2. At this time, the drain outlet 6 is provided at the bottom of the suction chamber 2. A drain discharge pipe 7 is connected to the drain discharge port 6, and a drain discharge valve 8 is provided in the drain discharge pipe 7. The drain discharge pipe 7 takes out the drain from the steam ejector 1 and sends the drain to the water ejector 9. The other end of the drain discharge pipe 7 is connected to the water ejector 9.

The steam supply control valve 13, the circulation pump 1
4. A control device 12 connected to the drain discharge valve 8 is provided.
The procedure of the vacuum cooling operation is set in the control device 12, and
The operation of the steam supply control valve 13, the circulation pump 14, and the drain discharge valve 8 is controlled by the control device 12.

When cooling food, the food to be cooled is stored in a vacuum chamber 10 and hermetically sealed.
Is performed under reduced pressure. The control device 12 sends the circulating water to the water ejector 9 by operating the circulating pump 14,
The decompression operation by the water ejector 9 is performed. Water ejector 9
At the beginning of the cooling step in which the pressure in the vacuum chamber 10 is reduced by only the pressure, the steam supply control valve 13 is closed and the drain discharge valve 8 is open. When the decompression operation is performed by the water ejector 9, the water ejector 9 sucks the air in the vacuum tank 10 through the air suction pipe 11 and the drain in the steam ejector 1 through the drain discharge pipe 7. The drain sucked at this time is a drain accumulated in the steam ejector 1 during the previous pressure reducing operation by the steam ejector, and a drain evaporated from food and condensed in the steam ejector 1 during the initial stage of the vacuum process.

When the pressure reduction by the water ejector 9 alone is performed for a predetermined time, the control device 12 opens the steam supply control valve 13 and the steam ejector 1 also performs the pressure reduction operation. When performing the decompression operation with the steam ejector, the control device 12 keeps the drain discharge valve 8 closed so that the steam ejector 1 does not suck air from the drain discharge pipe 7.

Since the amount of drain generated by one pressure reducing operation is small, it is not always necessary to discharge the drain every time the pressure reducing operation by the steam ejector is performed. But,
If the drain is not discharged at all, the drain accumulates in the steam ejector 1, and if the amount of drain in the steam ejector 1 increases, the drain may flow back through the air suction pipe 11. When the drainage valve 8 is opened and the steam ejector 1 and the water ejector 9 are passed through the drain discharge pipe 7 during the decompression operation using only the water ejector 9 at the beginning of the cooling process, the pressure difference between the steam ejector 1 and the water ejector 9 is increased. Thereby, the water ejector 9 sucks the drain in the steam ejector 1. The drain generated at the time of decompression by the steam ejector 1 is discharged in the early stage of the next cooling process. Therefore, the drain does not accumulate in the steam ejector 1 so much that the drain flows backward through the air suction pipe 11, and the drain flows backward. No longer occurs.

FIG. 2 shows a multi-stage steam ejector in which two steam ejectors 1 are installed. The configuration of each steam ejector 1 is the same as that of the steam ejector of FIG. Even if the number of the steam ejectors 1 increases, if the drain discharge port 6 is provided for each steam ejector 1 so that the drain can be discharged, the drain of each steam ejector can be discharged. 1 in that the tip of the drain discharge pipe 7 is not connected to the water ejector 9. The other points are the same as those in FIG.

In this embodiment, since the drain discharge pipe 7 is not connected to the water ejector 9, there is no need to associate the opening and closing of the drain discharge valve 8 with the operation of the circulation pump 14.
Also in this case, the drain discharge valve 8 is closed during the pressure reducing operation by the steam ejector 1, and the drain discharge valve 8 is opened only when the pressure reduction by the steam ejector 1 is not performed.
By opening the drain discharge valve 8 only when the pressure is not reduced by the steam ejector 1, the drain in the steam ejector 1 can be discharged without the steam ejector 1 sucking air from the drain discharge pipe 7. However, the drain discharge pipe 7 is connected to the water ejector 9 and the water ejector 9
As a result, it becomes difficult to discharge the drain as compared with the case where the drain is sucked.

Incidentally, even in the case of a multi-stage steam ejector,
First, the water ejector 9 is activated, and the two steam ejectors 1
If the operation is to be performed later, the tip of the drain discharge pipe 7 is connected to the water ejector 9 and the drain discharge valve 8 is opened and the steam discharge is performed by the drain discharge pipe 7 when the pressure reducing operation is performed only by the water ejector 9. Ejector 1 and water ejector 9
The drain in the steam ejector 1 may be sucked by the water ejector 9 by allowing the water ejector 9 to pass through.

The drain discharge valve 8 is connected to the steam ejector 1
Is opened and closed to prevent air from being sucked into the steam ejector 1, so that it is opened only when the action of discharging from the steam ejector 1 in place of the drain discharge valve 8 is applied. A check valve that does not open when the action of sucking into the steam ejector 1 is applied may be provided. If the drain valve 8 and the check valve that are opened and closed by the control device 12 are provided in series, the safety is further improved.

[0019]

By implementing the present invention, the amount of drain in the steam ejector is increased, and it is possible to prevent the drain from flowing back to the vacuum chamber through the air suction pipe.

[Brief description of the drawings]

FIG. 1 is a flowchart of a vacuum cooling device provided with a steam ejector embodying the present invention.

FIG. 2 is a flowchart of a vacuum cooling device according to another embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Steam ejector 2 Suction chamber 3 Steam nozzle 4 Diffuser 5 Intake port 6 Drain discharge port 7 Drain discharge pipe 8 Drain discharge valve 9 Water ejector 10 Vacuum tank 11 Air suction pipe 12 Control device 13 Steam supply control valve 14 Circulation pump

Claims (3)

[Claims] 1. A steam nozzle provided in a suction chamber and a diffuser connected to a side surface of the suction chamber. The suction chamber is connected to a vacuum tank by an air suction pipe, and the steam is injected from the steam nozzle toward the diffuser. Thus, in the steam ejector that depressurizes the inside of the vacuum chamber, a drain outlet is provided at the bottom of the suction chamber, a drain outlet is connected to the drain outlet, and a drain outlet valve is provided in the drain outlet, and a steam outlet is provided. A steam ejector provided with drain discharge means, characterized in that a drain discharge valve is opened to discharge drain in the steam ejector when the steam injection is not performed. 2. The steam ejector provided with the drain discharge means according to claim 1, further comprising a vacuum generator which operates prior to the steam ejector, in addition to the steam ejector provided with the drain discharge port, A multistage vacuum generation system in which a steam ejector provided with a drain discharge port is operated after a preceding vacuum generation device is operated, wherein a drain discharge pipe connected to a drain discharge port of the steam ejector is provided with Connect the end to the preceding vacuum generator,
The preceding vacuum generation device is operating, and in the steam ejector provided with the drain discharge port, the drain discharge valve is opened when not operating, and the drain in the steam ejector is sucked and discharged by the preceding vacuum generation device. A steam ejector provided with drain discharge means. 3. The steam ejector provided with the drain discharge means according to claim 1, wherein the drain discharge valve is opened only when the action of discharging from the steam ejector is applied, and the action of suctioning to the steam ejector is applied. A steam ejector provided with a drain discharge means, which is a check valve that does not open in some cases.