JPH05213317A - Vacuum pressure controller of automatic package machine - Google Patents

Abstract

PURPOSE:To prevent liquid filled in a bag from boiling and flowing out when operation stops due to a trouble during operation of a machine, causing the vacuum pressure in a vacuum chamber to rise. CONSTITUTION:In a vacuum packaging machine, a bag 1 filled with a content is put in a vacuum chamber 2 and packaging is carried out as the chamber 2 is intermittently moved. A changeover valve 4 and a vacuum detecting switch 6 whose set point is variable are mounted on a pipeline 5 that connects the chamber 2 at the stop position and a vacuum pump 3, and the changeover valve 5 is adequately switched according to detected signals of the detecting switch 6 to regulate the vacuum pressure in the vacuum chamber 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vacuum pressure control device for adjusting the vacuum pressure in a vacuum chamber in a vacuum packaging machine.

[0002]

2. Description of the Related Art FIG. 5 shows an outline of a vacuum packaging system. In a filling step A, a bag 1 is intermittently rotated together with a table T ₁ while a filling material is accommodated therein, and then a vacuum packaging step B is performed. In the vacuum packaging step B, the bag 1 is received in the vacuum chamber 2, vacuum-packed while being intermittently rotated together with the table T ₂ , and then discharged to the next step.

[0003]

As shown in FIG. 5, the vacuum packaging machine is provided with a plurality of (12 in the illustrated example) vacuum chambers 2 and is vacuum-packed while being intermittently rotated. At that time, the vacuum chamber 2 moves from the table position (4) to
In (5) or (6) to (7), the vacuum action is applied via the pipes arranged at the respective table positions. By the way, when the filling in the bag 1 is liquid, it is boiled when the inside of the bag 1 reaches a certain vacuum value due to the vacuum action. At this time, the conventional vacuum pump and vacuum chamber are connected by a conduit. Since there is a time delay in the degree of increase in vacuum pressure between the two positions, the vacuum pressure in the chamber is reduced while the vacuum chamber is stopped at the predetermined table position for a predetermined time. The set pressure for controlling the vacuum pump is set slightly higher than the boiling limit of the liquid so that the optimum vacuum pressure is obtained.

Therefore, although there is no problem when the packaging machine is operating normally, for example, when the machine operation is temporarily stopped due to a wait for filling, etc. other than the normal schedule, the vacuum chamber is stopped at the table position. However, as a result of continuing the vacuum action for more than the predetermined time, the inside of the bag becomes a predetermined vacuum pressure or more (or reaches the boiling limit value), the liquid boils and spills from the bag mouth, There were problems such as contamination, insufficient measurement, and abnormal seals.

[0005]

SUMMARY OF THE INVENTION The present invention is intended to solve the above problems, and is characterized in that a bag containing a filling is received in a vacuum chamber and the chamber is intermittently moved. A vacuum packaging machine for performing vacuum packaging while performing a vacuum switch, wherein a switching valve and a vacuum detection switch with a variable set value are inserted in the pipeline connecting the chamber and the vacuum pump at the stop position of the chamber. The switching valve is appropriately switched on the basis of the detection signal to control the vacuum pressure in the vacuum chamber.

[0006]

A switching valve and a vacuum pressure detection switch are inserted in the middle of a pipe line connecting the vacuum chamber stop position and the vacuum pump, and the switching valve is appropriately switched based on the detection signal of the detection switch.
Since the vacuum pressure in the vacuum chamber is controlled, the vacuum pressure in the chamber is properly controlled even if the vacuum action time exceeds a predetermined time, and the filling liquid in the bag does not boil.
Further, since the vacuum pressure control device is provided for each stop position of the vacuum chamber, multi-stage vacuum packaging can be performed. Further, one vacuum pump is commonly used for a plurality of pipelines, or one vacuum pump is used for a plurality of stop positions of the vacuum chamber.
By sharing a set of vacuum pressure control devices, the installation space can be reduced.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a first embodiment, which is the basic structure of the present invention, in which a specific position of the vacuum packaging machine B (see FIG. 5) and the vacuum pump 3 are provided as a single conduit 5. The vacuum pump 3 is operated to apply a vacuum action to the vacuum chamber 2 which has come to the position.
In addition, an electromagnetic switching valve 4 and a vacuum pressure detection switch 6 are inserted in the middle of the pipeline 5, the vacuum pressure in the pipeline 5 is detected by the detection switch 6, and the detection signal is piezoelectrically converted. A command signal 7 is sent to the electromagnetic switching valve 4, and the switching valve 4
Is appropriately switched to open / close the pipe line 5 and the suction action of the vacuum pump 3 is turned on / off to control the vacuum pressure in the vacuum chamber 2 to a predetermined vacuum pressure.

The vacuum pressure detection switch 6 is designed so that the upper limit setting value and the lower limit setting value can be arbitrarily changed, and is activated when the vacuum value in the conduit 5 rises and reaches the upper limit setting value,
The electromagnetic switching valve 4 is closed by issuing a detection signal, and it operates when the vacuum pressure in the pipeline 5 gradually decreases to reach the lower limit set value. By issuing a detection vibration and opening the electromagnetic switching valve 4, the pipeline is opened. 5
(In other words, the vacuum pressure in the vacuum chamber 2) is controlled so that it is always within a predetermined range.

At this time, there is a time delay between the vacuum pressure detecting device in the conduit 5 and the vacuum chamber 2 with respect to the suction action of the vacuum pump 3. Therefore, while the vacuum chamber 2 is stopped at a predetermined table position for a predetermined time, the upper and lower limit setting values of the vacuum pressure detection switch 6 are set so that the vacuum pressure in the chamber 2 is just the optimum vacuum pressure for packaging. It is set slightly higher than the boiling limit of.

Next, the operation of this apparatus will be described. Vacuum chamber 2 that received the bag 1 containing the filling in the previous step
Rotates and stops at a predetermined table position, and the vacuum pump 3
Due to the suction action, the inside gradually becomes a vacuum state.
At this time, the vacuum pressure in the pipeline 5 (vacuum chamber 2) is constantly monitored by the vacuum pressure detection switch 6, and when the interior of the pipeline 5 reaches the upper limit set value of the detection switch 6, the detection signal is the command signal 7 And is sent to the electromagnetic switching valve 4 to close the electromagnetic switching valve 4 and close the conduit 5.

As a result, the suction action of the vacuum pump 3 is stopped, the inside of the conduit 5 is maintained within the upper and lower limit set value range, and the inside of the vacuum chamber 2 is maintained at the optimum vacuum pressure. Then,
While continuing the suction action, the inside of the pipeline 5 is the detection switch 6
When it falls below the lower limit set value of, the detection signal is the command signal 7
And is sent to the electromagnetic switching valve 4, which opens the electromagnetic switching valve 4 and opens the conduit 5. Then, the suction action by the vacuum pump 3 is restarted, the vacuum pressure in the conduit 5 rises and is maintained within the upper and lower limit set value ranges, and the vacuum chamber 2 is maintained at the optimum vacuum pressure.

As described above, the inside of the vacuum chamber 2 is always kept in the optimum vacuum pressure range and the normal vacuum packaging is performed. However, for example, an unexpected trouble occurs, the machine operation is stopped, and the vacuum chamber is When 2 stops at the predetermined table position for longer than the predetermined stop time, the suction action time naturally becomes longer than the predetermined time as long as the vacuum pump 3 is operating,
The vacuum pressure in the pipeline 5 and the vacuum chamber 2 tries to rise beyond the set value, but at such a time, the detection switch 6 provided in the pipeline 5 immediately detects the rise value, and the detection signal is the command signal. 7 is sent to the electromagnetic switching valve 4, and the switching valve 4 is closed and the pipe line 5 is closed to stop the suction action.
Thus, the inside of the pipe 5 is kept within a predetermined range, and the inside of the vacuum chamber 2 is also kept at a predetermined optimum vacuum value, so that the filling liquid in the bag 1 does not boil. After this, when the machine operation is restarted, the normal vacuum packaging work is continued again.

FIG. 2 shows a second embodiment, in which a plurality of table positions (N in FIG. 5) at which the vacuum chamber 2 is stopped.
o. 4, 5, 6, and 7 positions), one vacuum pump 3 is arranged and connected by a pipe line 5, and an electromagnetic switching valve 4, a vacuum pressure detection switch 6, and a command signal 7 ( A vacuum pressure control device including a piezoelectric transducer is provided. In the case of the present embodiment, the specific bag 1 in the chamber 2 can be vacuum-packed in multiple stages. For example, at the table position 4 shown in FIG. 5 (that is, in FIG. A), the upper and lower set values of the vacuum pressure detection switch 6 are set to be lower than the predetermined set values to perform the primary vacuum process, and then the table At the position 5 (that is, in FIG. B), by setting the upper and lower set values of the vacuum detection switch 6 to a predetermined set value and performing the secondary vacuum process, pump efficiency is improved and effective vacuum packaging is possible. And

FIG. 3 shows a third embodiment. A set of vacuum pressure control devices, that is, an electromagnetic switching valve 4, a vacuum pressure detection switch 6, and a command signal are provided in each of the pipe lines 5 connected to a plurality of table positions. 7 (piezoelectric converter) is provided, and a plurality of (two in the figure) conduits 5 are connected to be shared by one vacuum pump 3. In the case of the present embodiment as well, similar to the second embodiment, it is possible to carry out vacuum packaging in multiple stages. or,
Since the vacuum pump 3 is shared, there is an advantage that the installation space is small.

FIG. 4 shows a fourth embodiment, in which a pipe line 5 connected to a plurality of table positions (three positions in the figure)
One connected to a book and connected to a vacuum pump 3, and a line 5 provided with a set of a vacuum pressure control device, that is, an electromagnetic switching valve 4, a vacuum pressure detection switch 6, and a command signal 7 (piezoelectric converter). Is. In the present embodiment, one set of vacuum pressure control device is shared for a plurality of table positions, so that the same vacuum pressure is applied to each vacuum chamber 2, and at the same time, vacuum packaging is performed. Similar to the above, there is an advantage that the installation space can be small. In each of the second to fourth embodiments, the vacuum pressure in the pipeline 5 is set to a predetermined value regardless of the vacuum working time by the action of the vacuum pressure control device installed in the pipeline 5 as in the first embodiment. Since the value is maintained within the value range and the vacuum pressure in the vacuum chamber 2 is maintained at the optimum vacuum value, the filling liquid in the bag 1 does not boil and spill from the bag mouth.

[0016]

According to the device of the present invention, the following excellent effects can be obtained. At the stop position of the vacuum chamber, a switching valve and a vacuum pressure detection switch with a variable set value are inserted in the middle of the pipeline connecting the vacuum chamber and the vacuum pump, and the switching valve is appropriately set based on the detection signal of the detection switch. Since the vacuum pressure inside the vacuum chamber is controlled by switching, even if the vacuum action time applied to the vacuum chamber becomes longer than the predetermined time due to a trouble or the like, the vacuum chamber is kept at the predetermined vacuum pressure. Therefore, the filling liquid in the bag in the vacuum chamber does not boil and spill from the bag mouth. Since a vacuum pressure control device is provided for each stop position of the vacuum chamber, the chamber vacuum pressure can be maintained at a predetermined vacuum pressure as in the above section, and the bag filling liquid in the vacuum chamber boils. In addition to avoiding spilling from the bag mouth, it is possible to perform vacuum packaging in multiple stages, improve pump efficiency, and perform effective vacuum packaging. Since one vacuum pump is shared by a plurality of pipelines, the chamber vacuum pressure can be maintained at a predetermined vacuum pressure as in the above item, and the bag filling liquid in the chamber is boiled and the bag mouth is closed. In addition to preventing spillage, there is an advantage that vacuum packaging can be carried out in multiple stages as in the above item and the installation space can be small. Since one set of vacuum pressure control device is shared for a plurality of stop positions of the vacuum chamber, the vacuum pressure in the chamber can be maintained at a predetermined vacuum pressure as in the above item, and the filling liquid in the bag inside the chamber can be maintained. It has the advantage that it does not boil and spill out of the bag mouth, and it requires a small installation space as in the above item.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a first embodiment.

FIG. 2 is a configuration diagram of a second embodiment.

FIG. 3 is a configuration diagram of a third embodiment.

FIG. 4 is a configuration diagram of a fourth embodiment.

FIG. 5 is a process schematic diagram of a vacuum packaging device.

[Explanation of symbols] 1 bag 2 vacuum chamber 3 vacuum pump 4 electromagnetic switching valve 5 conduit 6 vacuum trace detection switch 7 command signal (piezoelectric converter)

Claims (1)

[Claims] 1. A vacuum packaging machine for receiving a bag containing a filling material in a vacuum chamber and vacuum-packing the chamber while intermittently moving the chamber, wherein the chamber and a vacuum pump are in a stop position of the chamber. A switching valve and a vacuum detection switch with a variable set value are inserted in the middle of the pipeline connecting the two, and the switching valve is appropriately switched based on the detection signal of the detection switch to control the vacuum pressure in the vacuum chamber. A vacuum pressure control device for a vacuum packaging machine, which is characterized in that