JPH05170225A - Vacuum packaging apparatus - Google Patents

Abstract

PURPOSE:To obtain a vacuum packaging apparatus which can always keep the packing quality within a specified range even if there are deviations in the function of machinery like a vacuum pump or there are variations in the condition of the contents in bags. CONSTITUTION:The title vacuum packaging apparatus is provided with a chamber vessel which can be freely deaerated, a sealer closing the opening of bags in the chamber, a vacuum pump 11 connected to the chamber vessel through a deaeration valve 9, a pressure sensor communicating with the chamber vessel, and a controller 30 regulating a series of operational motions. This controller 30 is electrically connected to the sealer, the deaeration valve 9, the vacuum pump and the pressure sensor. Moreover, this controller has a judging function as to whether the pressure in the chamber vessel comes to a lower pressure than a specified one or not, a retaining function of closed condition by the deaeration valve 9 for a specified interval after start of counting when the pressure reaches a specified value, and a discriminating function as to whether the fluctuation of pressure reaches the ultimate condition or not.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vacuum packaging device or the like which puts food or the like in a bag material, degasses and seals it.

[0002]

2. Description of the Related Art So-called vacuum packaging, in which foods and the like are put in a bag material and the bag material is deaerated and depressurized and sealed, is generally performed as follows. That is, a bag material having one side opening in which an envelope bag such as food is put is put in a chamber which is connected to a vacuum pump through a pipe and can be depressurized. The opening edge to be closed is then placed in a sealable position. The lid of the chamber is closed, and an operation called a deaeration step, that is, an operation of operating the vacuum pump to remove the gas in the chamber is performed. In order to perform an appropriate vacuum packaging, the pressure sensor detects that the pressure in the chamber communicating with the inside of the bag material reaches a predetermined pressure, and then the sealing device closes the opening side of the bag material. Finally, the atmosphere release valve connected to the pipe is opened, the chamber is returned to atmospheric pressure, and the sealed bag material is taken out.
A technique for detecting that the pressure in the chamber has dropped to a predetermined pressure is disclosed in Japanese Utility Model Laid-Open No. 61-129705, Japanese Utility Model Laid-Open No. 2-6.
As known from Japanese Patent Publication No. 9806, etc., if a vacuum pump having a predetermined capacity is operated for a certain period of time, it should drop to a predetermined pressure. Therefore, a timer device is used instead of the pressure sensor,
It is also practiced to finish the degassing process by operating the vacuum pump for a certain period of time.

[0003]

In the prior art described above, in which the pressure drop is detected in the chamber by using the pressure sensor, the pressure directly measured is the internal pressure of the chamber, not the internal pressure of the bag material. .. For this reason, there is a problem in that the inner pressure of the chamber and the inner pressure of the bag material are different due to the degree of closing of the opening of the bag material, the vapor pressure of the wrapped bag material, and the like, and the packaging quality of food and the like is not constant. Also, in the case of using a timer to terminate the degassing process after the vacuum pump has been operated for a certain period of time, if the performance of the vacuum pump or the like fluctuates or the contents of the packaged items vary, the chamber There was a problem that the reached internal pressure, and consequently the internal pressure of the bag material, varied and the packaging quality was not constant.

Therefore, it is an object of the present invention to always maintain the packaging quality within a predetermined range regardless of variations in the performance of machines such as vacuum pumps and variations in the contents of bag materials. To provide a possible vacuum packaging device.

[0005]

In order to achieve the above object, according to the present invention, a vacuum packaging apparatus includes a chamber container provided with an openable / closable lid and capable of decompressing, and the chamber container provided in the chamber container. A seal device that closes the opening of the bag material set inside, a vacuum pump that communicates with the chamber container through a degassing valve, a pressure sensor that is provided in communication with the inside of the chamber container, and a series of operations. And a control device for controlling the operation. This control device electrically communicates with a sealing device, a degassing valve, a vacuum pump, a pressure sensor, etc., and a means for judging whether the pressure in the chamber container has reached a predetermined value or less, and the pressure is a predetermined value. It has means for starting counting when it reaches a value or less and maintaining the degassing state by keeping the degassing valve closed for a predetermined time, and means for discriminating that the fluctuation of the pressure has reached the saturated state.

[0006]

The bag material containing the member to be packaged is placed in the chamber container, the lid is closed, the deaeration valve is opened, and the vacuum pump is operated to deaerate and decompress the chamber container. The control device, which receives the pressure signal of the chamber container from the pressure sensor, determines whether the detected pressure has reached the target predetermined pressure, and if it reaches, activates the deaeration holding timer and waits until the count increases. Keep the inside degassed. On the other hand, the control device starts the operation of the saturation check timer for checking the pressure saturation state at the same time as the start of the degassing operation, and after counting up, determines whether the pressure fluctuation is within a predetermined range. This pressure fluctuation determination signal is used as a degassing process completion signal or a degassing holding timer operation start signal. After shifting to the sealing process, the sealing device is operated to close the opening of the bag material. The pressure in the chamber container is finally returned to atmospheric pressure to complete the packaging.

[0007]

Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings. In the drawings, the same reference numerals indicate the same or corresponding parts.

In FIG. 1, a chamber container 1 has an openable / closable chamber lid 2 pivotally mounted by a pin (not shown) or the like, and a sealing packing 3 is provided on a joint surface between the chamber lid 2 and the container body 1a. Is installed. The pipe 5 connected to the degassing port 1b of the chamber container 1 is equipped with a pressure sensor 7 and communicates with a vacuum pump 11 via a degassing valve 9. The degassing valve 9 may be like an electromagnetically driven solenoid valve.

The chamber container 1 is provided with a sealing device 13. The sealing device 13 includes an actuator 15 attached to the bottom surface of the container body 1a, a heating fixing body 17 provided at the tip of a piston rod 15a of the actuator 15, and a chamber lid so as to face the heating fixing body 17. 2 and a heating receiver 19 attached to the lower surface of One pressure chamber of the actuator 15 opens to the atmosphere through the atmosphere port 15b, and the decompression port 15c
Communicates with the cylinder valve 23 via the pipe 21, and further communicates with the vacuum pump 11.

As will be described later, a heating body 17a connected to a power source is provided at the tip of the heating fixing body 17.

The pipe 5 communicates with a gas valve 25 and an atmosphere opening valve 27 via a branch pipe, and the gas valve 25 communicates with a gas cylinder 29 storing a replacement gas. Like the degassing valve 9, the cylinder valve 23, the gas valve 25, and the atmosphere opening valve 27 may be like a solenoid valve that drives a spool with a solenoid, but the internal connection configuration is as shown in FIG. The atmosphere opening valve 27 is open when the power is off, but the other valves are closed when the power is off and show a communication state as described later when the power is on.

FIG. 2 shows an electrical circuit for operating the device of FIG. In FIG. 2, the magnet switch M
The contacts MS ₁ and MS _{2 of} S are driving circuits 1 of the vacuum pump 11.
The control device 30 is provided in series with 1a and in parallel with this. The magnet switch MS, the drive circuit 9a for the degassing valve 9, the drive circuit 23a for the cylinder valve 23, the drive circuit 25a for the gas valve 25, the drive circuit 27a for the atmosphere release valve 27, and the transformer 17b for the heating element 17a are opened and closed, respectively. Contact points 33a, 33b, 33c, 33d, 33
e and 33f are connected in series, and these are connected to the control device 30.
Together, they constitute the control unit 31.

Next, the control device 30 will be described with reference to the block diagram of FIG.
The function of is explained. The control device 30 is electrically connected to the pressure sensor 7, and takes in the pressure change in the chamber container 1 converted into the voltage change by the pressure sensor 7. The start switch SW may be a manual push button or a door switch that is activated when the chamber lid 2 closes the chamber container 1, and can be displayed like a contact 33a. The degassing setting is a setting of a pressure value for outputting a completion signal of the degassing process, as will be described later. The seal setting sets the energization time of the heating body 17a, and controls the opening / closing of the contact 33f. The seal switch is a switch for forcibly shifting to the sealing process during the deaeration process (or gas replacement process). The gas pressure setting is for setting the gas replacement pressure. An attention light, which is activated as described below, is electrically connected.

The operation sequence of the apparatus having the above-described structure is shown in FIG.
As shown in FIG. 5, the process proceeds in the order of power ON → standby → degassing process → gas replacement process → sealing process → air opening process, and the magnet switch MS, vacuum pump 11, and
Deaeration valve 9, cylinder valve 23, gas valve 25,
The operating states of the atmosphere release valve 27 and the heating body 17a are as shown in FIG.

As shown in FIG. 5, in the standby state, the bag material a (see FIG. 1) containing the article b to be packaged is put in the chamber container 1. The power source of the atmosphere opening valve 27 is OFF and is open as shown in FIGS.

As shown in the flow chart of FIG. 6, when the degassing step is started, the controller 30 operates as follows. Whether the start switch is ON or OFF is judged, and if it is ON, as shown in FIG. 5, the vacuum pump 11, the deaeration valve 9, and the atmosphere release valve 27 are all turned on, and the deaeration operation is started. The pressure value is input, and the pressure saturation check timer restarts. The internal pressure of the chamber container 1 does not fall below the first predetermined pressure for a while, and the saturation check timer does not count up, so this determination is repeated. When degassing progresses and the internal pressure becomes equal to or lower than the first predetermined pressure, the degassing valve 9 is turned off and closed, and the degassing holding timer is restarted. Before the degassing holding timer counts up, if the pressure inside the chamber container 1 rises above the second predetermined pressure due to the influence of the vapor pressure of the object to be packaged, etc., the degassing valve 9 is turned on again to open and degas. Qi operation resumes. Then, if the degassing holding timer counts up, the degassing process is completed, and the process proceeds to the sealing process or the gas replacement process.

When it is difficult for the internal pressure of the chamber container 1 to drop (when the performance of the vacuum pump 11 is lowered for some reason), the saturation check timer counts up first. Then, it is determined whether or not the pressure fluctuation is equal to or less than a predetermined value. If the pressure fluctuation is less than or equal to the predetermined value, the deaeration step is ended with the saturated state in which deaeration does not proceed any further. The warning lamp is turned on to warn that the internal pressure of the chamber container 1 has not dropped to a predetermined value.

Next, another control procedure of the control device 30 will be described with reference to FIG. Since the flowcharts of FIGS. 6 and 7 are duplicated, only different parts will be described. In FIG. 7, the YES signal after the saturation check-up timer counts up and the pressure fluctuation range is determined is the deaeration hold. Used for timer restart. By doing so, the deaeration valve 9 is closed and the deaeration is performed both when the internal pressure of the chamber container 1 reaches the predetermined value or less and when the pressure reaches the saturated state otherwise. The degassing state is held until the holding timer counts up. For this reason, even if the pressure changes thereafter due to the opening condition and the internal condition of the bag material a, the deaeration valve is opened and re-deaeration is performed, and a good pressure state can be obtained.

FIG. 8 shows a control procedure similar to that of FIG. In FIG. 7, the degassing process is terminated by counting up the degassing holding timer that starts operation when the degassing valve is closed at the first predetermined pressure or when the depressurization speed is less than or equal to the predetermined depressurization speed.
In FIG. 8, the deaeration holding timer is reset when the first predetermined pressure is reached during the counting of the deaeration holding timer which has started to operate at the predetermined decompression speed.

When the deaeration process is completed as described above, the gas replacement process is started. The degassing valve 9 is closed, and the gas valve 25 is turned on and opened.
Gas is supplied into the chamber container 1 from the gas cylinder 29 held at a predetermined pressure. The gas is supplied until the pressure in the chamber container 1 reaches a predetermined value. However, there is a difference between the pressure decreasing and increasing, but the target pressure value is reached in the above point. The control procedure in the degassing process is common. Therefore, the concept of the control procedure shown in the flowcharts of FIGS. 6, 7, and 8 can be used for the control procedure of the gas replacement step.

As shown in FIG. 5, when the replacement gas pressure in the chamber container 1 reaches a predetermined value, the gas valve 25 is once closed to maintain the replacement state. While the hold timer is counting,
When the pressure of the replacement gas decreases, the gas valve 25 is opened again, and gas is replenished from the gas cylinder 11.

When the gas replacement is completed, the process proceeds to the sealing process. The gas valve 25 and the degassing valve 9 are closed, and the cylinder valve 23 is opened. Vacuum pump 11
Removes air from the upper pressure chamber of the actuator 15, and the piston rod 15a, that is, the heating fixing body 17 moves up and approaches the heating receiving body 19. The heating element 17a is energized to seal the opening of the bag material a. That is, the vacuum pump 11 operates the sealing device 13 to perform sealing.

When the sealing process is completed, the air release valve 27 is turned off and opened, and the other valves are closed. When the internal pressure of the chamber container 1 returns to the atmospheric pressure, the lid 2 is easily opened and the bag material is taken out.

[0024]

According to the present invention described above, the control device is
Since it has a deaeration holding function, the deaerated state inside the chamber container can be maintained, the difference between the chamber container internal pressure and the bag material internal pressure can be eliminated, and high packaging quality can be maintained. Further, since the saturated state of the pressure fluctuation in the chamber container can be detected, it is possible to prevent the deaeration process and the gas replacement process from being prolonged, and it is possible to perform an efficient operation.

[Brief description of drawings]

FIG. 1 is an overall system diagram of an embodiment of the present invention.

FIG. 2 is an electric circuit diagram of the embodiment.

FIG. 3 is a functional explanatory diagram of a main part of the embodiment.

FIG. 4 is a process diagram of the embodiment.

FIG. 5 is an explanatory view of the operation of each device in each step of the above embodiment.

FIG. 6 is a flow chart showing a control procedure by the control device in the embodiment.

FIG. 7 is a flowchart showing another control procedure by the control device.

FIG. 8 is a flowchart showing still another control procedure by the control device.

[Explanation of symbols]

 1 Chamber Container 2 Lid 7 Pressure Sensor 9 Degassing Valve 11 Vacuum Pump 13 Sealing Device 30 Control Device

Claims (1)

[Claims] 1. A depressurizable chamber container having an openable / closable lid, a sealing device provided in the chamber container for closing an opening of a bag material set in the chamber container, and a degassing valve for the chamber container. A pressure sensor provided in communication with the inside of the chamber container, and a control device, and the control device includes the sealing device, the deaeration valve, the vacuum pump, and the pressure. Means for electrically contacting the sensor to determine whether the pressure in the chamber container has reached a predetermined value or less; and degassing for a predetermined time by starting counting when the pressure has reached a predetermined value or less. A vacuum packaging device comprising: a means for holding the state; and a means for discriminating that the variation in the pressure has reached a saturated state.