JP6121817B2 - Vacuum packaging machine - Google Patents

Description

  The present invention relates to a vacuum packaging machine that evacuates a chamber with an oil rotary vacuum pump and seals a packaging bag with a sealing device for vacuum packaging.

  The following Patent Document 1 discloses a vacuum packaging machine that vacuum-wraps a packaging bag containing an object to be packaged such as food and cooked food. This vacuum packaging machine includes a chamber for storing a packaging bag containing foodstuffs, a sealing device provided in the chamber for sealing the periphery of the opening of the packaging bag, and an oil circulation for degassing the chamber and depressurizing it. An oil rotary vacuum pump and a vacuum gauge for detecting the pressure in the chamber. In this vacuum packaging machine, the oil rotary vacuum pump is operated so that the pressure in the chamber detected by the vacuum gauge becomes a predetermined value, and the opening peripheral edge of the packaging bag accommodated in the chamber is sealed by the sealing device. The packaging bag is vacuum-packed.

JP 2000-142621 A

  In the vacuum packaging machine as described above, when the inside of the chamber is degassed by an oil rotary vacuum pump to make it negative pressure, the moisture contained in the food in the packaging bag is mixed into the oil in the oil rotary vacuum pump. The oil in the oil rotary vacuum pump sometimes deteriorated. When the oil in the oil rotary vacuum pump deteriorates due to the mixing of water, the oil rotary vacuum pump may not be able to reduce the pressure in the chamber to a preset value. In this case, for example, the oil rotary vacuum pump is warmed up to evaporate water contained in the oil. However, the warm-up operation of the oil rotary vacuum pump operates the oil rotary vacuum pump for a set time regardless of the amount of water mixed in the oil, so remove it sufficiently when there is a lot of water mixed in the oil. There was something that could not be done. If the water mixed in the oil cannot be removed sufficiently, when the packaging bag is vacuum packed, the oil rotary vacuum pump cannot reduce the pressure in the chamber to the set value, and the oil rotary vacuum pump is warmed up again. I had to drive. Further, when the amount of water mixed in the oil of the oil rotary vacuum pump is small, the warm-up operation may be performed more than necessary, and the time during which the vacuum packaging machine cannot be used is unnecessarily long. An object of the present invention is to make it possible to reliably remove water mixed in oil of an oil rotary vacuum pump that deaerates a chamber of a vacuum packaging machine to make a negative pressure in a minimum time.

  In order to solve the above-described problems, the present invention provides a chamber that accommodates a packaging bag that accommodates an object to be packaged, a sealing device that is provided in the chamber and seals the periphery of the opening of the packaging bag, and the interior of the chamber is deaerated. An oil rotary vacuum pump for negative pressure, a vacuum circuit for connecting the chamber and the oil rotary vacuum pump, a vacuum valve for interposing the vacuum circuit to open and close the vacuum circuit, and an oil rotary vacuum pump An atmosphere introduction circuit for introducing the atmosphere into the atmosphere, an atmosphere introduction valve for opening and closing the atmosphere introduction circuit through the atmosphere introduction circuit, a vacuum gauge for detecting the pressure in the chamber, and a chamber detected by the vacuum gauge In a vacuum packaging machine that controls the oil rotary vacuum pump to operate so that the internal pressure becomes a predetermined value and seals the packaging bag accommodated in the chamber by a sealing device, When you open the valve In addition, the oil rotary vacuum pump is operated to heat and vaporize the water mixed in the oil of the oil rotary vacuum pump, and the air introduction valve is opened with the oil rotary vacuum pump activated after the warm-up process. And having a drainage operation program that removes water mixed in the oil of the oil rotary vacuum pump by alternately executing a ventilation process that discharges the water vaporized during the warm-up process together with the exhaust. The vacuum packaging machine is provided.

  In the vacuum packaging machine configured as described above, the warm-up process of opening the vacuum valve and operating the oil rotary vacuum pump to heat and vaporize water mixed in the oil of the oil rotary vacuum pump, and after the warm-up process With the oil rotary vacuum pump activated, the air introduction valve is opened, and the ventilation step of discharging the water vaporized during the warm-up process together with the exhaust is alternately performed to Since it has a drainage operation program that removes water mixed in oil, the water vaporized by the warm-up process can be positively released along with the exhaust during the ventilation process, compared to draining only the warm-up process. As a result, water can be efficiently removed from the oil, and the time for draining can be greatly reduced.

  In the vacuum packaging machine configured as described above, when the warm-up process is executed, the time during which the pressure detected by the vacuum gauge passes a predetermined pressure range, until the pressure detected by the vacuum gauge reaches a predetermined value. Based on the time or the pressure detected by the vacuum gauge after a predetermined time, the calculation means for calculating the time required to remove the water mixed in the oil of the oil rotary vacuum pump, from the time calculated by this calculation means It is preferable to display the time until the drainage operation program ends, or the elapsed time since the start of the drainage operation program, and the time until the drainage operation program ends is displayed. The drainage operation program can be executed until the water mixed in the oil of the oil rotary vacuum pump is removed, and the vacuum packaging machine cannot be used for vacuum packaging. The ability to grip, it has become possible to apply the time the operator can not use the vacuum packaging machine for other tasks. In addition, by displaying the elapsed time since the start of the drainage operation program, let other workers know that vacuum packaging is not possible because the vacuum packaging machine is running drainage. Can do.

  In the vacuum packaging machine configured as described above, every time the warm-up process is executed, the time required to remove the water mixed in the oil of the oil rotary vacuum pump is calculated by the calculation means, and the water is drained from the calculated time. It is preferable to display the time until the operation program ends, and in this case, the time until the end predicted at the beginning of the drainage operation program may vary depending on various conditions such as temperature. Since the time from when the predicted time was calculated to the end of the drainage operation program was displayed for each machine process, it became possible to know the exact time at which the drainage operation program ended.

  In the vacuum packaging machine configured as described above, when the warm-up process is executed under the condition that the pressure detected by the vacuum gauge when the warm-up process is executed is not mixed with water in the oil of the oil rotary vacuum pump. It is preferable to detect that the water mixed in the oil of the oil rotary vacuum pump has been removed when the pressure becomes the same as the pressure. In this case, water is mixed in the oil of the oil rotary vacuum pump. It is now possible to reliably remove water until no condition exists.

  In the vacuum packaging machine configured as described above, it is preferable to display the time when the drainage operation program is executed after the drainage operation program is completed. The amount of water mixed in the oil of the oil rotary vacuum pump can be ascertained from the time of execution.

It is the perspective view which fractured | ruptured partially which shows one Embodiment of the vacuum packaging machine of this invention. It is the schematic which shows the piping which mainly connects a chamber and an oil rotary vacuum pump of a vacuum packaging machine. It is a figure which shows an operation panel. It is a block diagram which shows the control apparatus of a vacuum packaging machine. It is sectional drawing of the front part of a chamber base.

  Hereinafter, an embodiment of a vacuum packaging machine of the present invention will be described with reference to the accompanying drawings. As shown in FIG. 1 and FIG. 2, the vacuum packaging machine 10 includes a chamber 12 that houses a packaging bag for storing an object to be packaged such as food and cooked food, and a packaging bag in the chamber 12. A heating and sealing device (sealing device) 20 that seals the periphery of the opening, and an oil rotary vacuum pump 30 that evacuates the chamber 12 at the lower portion of the housing 11 to make it negative pressure.

  As shown in FIGS. 1 and 2, the chamber 12 has a shallow dish-shaped chamber base 13 having an open top surface, and a chamber cover 14 made of a pressure-resistant acrylic plate that covers the upper surface opening of the chamber base 13 so that it can be opened and closed. It is a pressure vessel composed of The chamber cover 14 is supported by the rear end portion of the housing 11 so as to be rotatable about a horizontal axis so that the front end side can move up and down.

  As shown in FIG. 1, a heat sealing device 20 is provided at the front of the chamber 12. The heat sealing device 20 seals the peripheral edge portion of the front opening of the packaging bag that can be thermally welded and accommodated in the chamber 12. Note that the packaging bag uses a thermoplastic resin film having a two-layer structure that employs a material having a low melting point on the inside. The heat sealing device 20 includes lower and upper narrow pressure blocks 21 and 22 that hold the peripheral edge of the opening of the packaging bag in a narrow pressure. The lower narrow pressure block 21 is made of an aluminum square pipe member, and is detachably attached to the front portion of the chamber base 13 and is movable up and down. On the upper surface of the lower narrow pressure block 21, a heater 23 in the form of a strip made of a nichrome material is provided. The upper narrow pressure block 22 is made of an elastically deformable silicon block body, and is provided at the front of the lower surface of the chamber cover 14 at a position facing the upper side of the lower narrow pressure block 21.

  As shown in FIGS. 1 and 2, a pair of left and right lifting mechanisms 24 (only the right side is shown in the figure) are provided at the front of the chamber base 13 to raise and lower the lower narrow pressure block 21 up and down. The elevating mechanism 24 includes a pair of left and right support shafts 25 that penetrate the bottom wall of the front portion of the chamber base 13. These support shafts 25 support the lower narrow pressure block 21 at the front portion of the chamber base 13 so as to be movable up and down. These support shafts 25 are inserted at the lower end of the lower narrow pressure block 21, and the support shaft 25 is vertically moved by a pair of left and right lifting cylinders 26 whose upper and lower intermediate portions are provided in front of the lower surface of the chamber base 13. Is supported so as to be movable. A flange portion 26a is provided in the middle of the support shaft 25 in the elevating cylinder 26, and the eaves portion 26a partitions the interior of the elevating cylinder 26 into an upper space 26b and a lower space 26c in an airtight manner. In the upper space 26b of the elevating cylinder 26, a spring (biasing means) 26d is interposed on the outer periphery of the support shaft 25, and the spring 26d urges the support shaft 25 downward through the flange portion 26a.

  As shown in FIGS. 1 and 2, an oil circulation type oil rotary vacuum pump 30 is provided in the housing 11, and the oil rotary vacuum pump 30 is interposed between components such as a rotor, a stator, and a blade by oil. It is a volume phase vacuum pump which aims to reduce airtightness and ineffective space. Specifically, a rotor that is rotated by an electric motor in a cylindrical stator filled with oil, and an inner peripheral surface of the stator that is incorporated in each rotor groove radially provided in the rotor so as to be movable in the radial direction. In the state where each space formed by the cylindrical stator and the rotor and the blade plate is hermetically sealed with oil, the volume is changed by the rotation of the rotor, and the air is The air is sucked from the suction port and discharged from the discharge port.

  As shown in FIG. 2, an intake pipe 31 that connects the oil rotary vacuum pump 30 and the chamber 12 is provided in the housing 11, and a vacuum valve 32 that opens and closes the intake pipe 31 is provided. Yes. The intake pipe 31 constitutes the evacuation circuit described in the claims of the present application. Connected to the intake pipe 31 is an atmosphere introduction pipe 33 for introducing the atmosphere between the chamber 12 and the vacuum valve 32. The air introduction pipe 33 includes a first pipe part 33a and a second pipe part 33b branched from the first pipe part 33a. The first and second pipe parts 33a and 33b are opened and closed by first and second parts. Air introduction valves 34 and 35 are provided. The first pipe portion 33a has a larger diameter than the second pipe portion 33b. When the first atmosphere introduction valve 34 is opened, the atmosphere is quickly introduced into the chamber 12, and when the second atmosphere introduction valve 35 is opened. The atmosphere is slowly introduced into the chamber 12. The atmosphere introduction pipe 33 (particularly the second pipe portion 33b) and a part of the intake pipe 31 constitute the atmosphere introduction circuit described in the claims of the present application.

  A vacuum detection tube 36 is connected to the second tube portion 33 b, and a vacuum gauge 37 that detects the pressure in the chamber 12 is provided in the vacuum detection tube 36. When the inside of the chamber 12 is not deaerated by the oil rotary vacuum pump 30, the pressure in the chamber 12 detected by the vacuum gauge 37 is 101 kPa (abs) which is the same as the atmospheric pressure, and the degree of vacuum at this time is 0%. is there. When the inside of the chamber 12 is degassed by the oil rotary vacuum pump 30 to be negative pressure, and the pressure in the chamber detected by the vacuum gauge 37 is 0 kPa (abs), the degree of vacuum is 100%. In the following description, when the pressure is displayed, the description of (abs) is omitted.

  A cylinder pipe 38 branched from between the oil rotary vacuum pump 30 and the vacuum valve 32 is connected to the intake pipe 31 to an upper space 26b of the elevating cylinder 26. The cylinder pipe 38 has a cylinder valve 39 for opening and closing the cylinder pipe 38. Is provided.

  An operation panel 40 for operating the vacuum packaging machine 10 is provided on the front surface of the housing 11. As shown in FIG. 3, the operation panel 40 is provided with various switches 41 for operating the vacuum packaging machine 10, and a display panel 42 for displaying the degree of vacuum in the chamber 12 and various programs. Yes.

  The vacuum packaging machine 10 includes a control device 50. As shown in FIG. 4, the control device 50 includes a heater 23, an oil rotary vacuum pump 30, a vacuum valve 32, and first and second atmospheric introduction valves. 34, 35, a vacuum gauge 37, a cylinder valve 39, and an operation panel 40. The control device 50 includes a microcomputer (not shown), and the microcomputer includes a CPU, a RAM, a ROM, and a timer (all not shown) connected via a bus. The control device 50 is provided with various vacuum packaging programs for vacuum-packaging the objects to be packaged in the chamber 12 in the ROM. When the various vacuum packaging programs are executed by the operation panel 40, the control device 50 detects the vacuum gauge 37. Based on this, the operations of the heater 23, the oil rotary vacuum pump 30, the vacuum valve 32, the first and second atmospheric introduction valves 34 and 35, and the cylinder valve 39 are controlled, and the object to be packaged in the chamber 12 is vacuumed. Packaging.

  Further, the control device 50 has a draining operation program for removing water mixed in the oil of the oil rotary vacuum pump 30 in the ROM. The draining operation program opens the vacuum valve 32 and controls the oil rotary vacuum pump 30. The warming-up process of heating and vaporizing water mixed in the oil of the oil rotary vacuum pump 30 and opening the second air introduction valve 35 in a state where the oil rotary vacuum pump 30 is operated after the warming-up process, The ventilation process which discharges | releases the water vaporized when performing the warming-up process with exhaust_gas | exhaustion is performed alternately. When the air introduction port at the tip of the second pipe portion 33b of the air introduction pipe 33 that introduces air during the ventilation process is provided at a position where the exhaust heat of the oil rotary vacuum pump 30 can be taken in, the ventilation process It is possible to suppress the oil temperature from being lowered by the introduced outside air, and it is possible to further increase the efficiency of draining water.

  The water draining operation program will be described in detail. First, in the warm-up process, the temperature of the oil in the oil rotary vacuum pump 30 is raised while operating the oil rotary vacuum pump 30 to deaerate the chamber 12 to make it negative pressure. The temperature of the water contained in the oil is also raised. By operating the oil rotary vacuum pump 30 and degassing the chamber 12 to make it a negative pressure, the oil rotary vacuum pump 30 is also in a negative pressure state, and the water contained in the oil is easily evaporated.

  In the ventilation process, after the warm-up process, the second rotary air introduction valve 35 is opened while the oil rotary vacuum pump 30 is operated, and the outside air is introduced into the oil rotary vacuum pump 30 from the second pipe portion 33b of the atmospheric inlet pipe 33. Thus, the vaporized water is discharged together with the exhaust gas. In order to prevent the chamber cover 14 from being opened during the ventilation process, the second pipe portion 33b of the air introduction pipe 33 has a pressure in the chamber 12 of 5 to 40 kPa (vacuum degree) with the oil rotary vacuum pump 30 operated. In the diameter of about 60% to 95%).

Further, the control device 50 has a calculation program (calculation means) in the ROM that calculates the time required to remove water mixed in the oil of the oil rotary vacuum pump 30 when the drainage operation program is executed. . The calculation program performs a measurement time (ta) when the pressure detected by the vacuum gauge 37 passes a predetermined pressure range (for example, 5 kPa to 1 kPa (95% to 99% in the degree of vacuum)) when the warm-up process is executed. Based on this, the time T required to remove the water mixed in the oil of the oil rotary vacuum pump 30 is calculated. More specifically, when the oil in the oil rotary vacuum pump 30 contains water, the ability of the oil rotary vacuum pump 30 to evacuate decreases, so the pressure detected by the vacuum gauge 37 during the warm-up process is a predetermined pressure. The time (ta) passing through the pressure range (for example, 5 kPa to 1 kPa (95% to 99% in the degree of vacuum)) is the same as the time (tb) measured in the state where water is not mixed in the oil of the oil rotary vacuum pump 30 Longer than The time obtained by dividing the time (ta) by the time (tb) is a time that is increased due to the water mixed in the oil of the oil rotary vacuum pump 30. Further, the water that can be removed when one cycle of the warming-up process and the ventilation process is performed is substantially constant, and the time (tc) that can be similarly reduced during the warming-up process due to this amount of water. ) Is also constant. From these, the time T required to remove the water mixed in the oil of the oil rotary vacuum pump 30 is:
T (s) = (ta−tb) / tc × (time required for one cycle of the warm-up process and the ventilation process)
Is calculated as The control device 50 causes the display panel 42 to display the time from the calculated time until the drainage operation program ends.

  In addition, when the drainage operation program is executed, the control device 50 executes the calculation program every time the warm-up process is executed, and the drainage operation program ends from the time calculated every time the warm-up process is executed. Is displayed on the display panel 42. When the drainage operation program is executed, the control device 50 warms up the pressure detected by the vacuum gauge 37 when the warm-up process is executed under the condition that water is not mixed in the oil of the oil rotary vacuum pump 30. When the pressure becomes the same as the pressure when the machine process is executed, it is detected that the water mixed in the oil of the oil rotary vacuum pump 30 has been removed. More specifically, when the control device 50 executes the warm-up process, the pressure detected by the vacuum gauge 37 after 30 seconds has passed as a predetermined time under the condition that water is not mixed in the oil of the oil rotary vacuum pump 30. When the pressure becomes 0.5 kPa (99.5% in vacuum) as the pressure when the warm-up process is executed, it is detected that the water mixed in the oil of the oil rotary vacuum pump 30 has been removed. .

In addition, the control device 50 has another calculation program. When the warm-up process is executed, the calculation program detects that the pressure detected by the vacuum gauge 37 is a predetermined value (for example, 1 kPa (99% for the degree of vacuum). The time T required to remove the water mixed in the oil of the oil rotary vacuum pump 30 is calculated based on the time (ta) until)). More specifically, when water is contained in the oil of the oil rotary vacuum pump 30, the ability of the oil rotary vacuum pump 30 to evacuate decreases, so that the vacuum gauge 37 detects when the warm-up process is executed. The time (ta) until the pressure reaches a predetermined value (for example, 1 kPa (99% in the degree of vacuum)) is compared with the time (tb) measured in the same manner when water is not mixed in the oil of the oil rotary vacuum pump 30. And get longer. The time obtained by dividing the time (ta) by the time (tb) is a time that is increased due to the water mixed in the oil of the oil rotary vacuum pump 30. Further, the water that can be removed when one cycle of the warming-up process and the ventilation process is performed is substantially constant, and the time (tc) that can be similarly reduced during the warming-up process due to this amount of water. ) Is also constant. From these, the time T required to remove the water mixed in the oil of the oil rotary vacuum pump 30 is:
T (s) = (ta−tb) / tc × (time required for one cycle of the warm-up process and the ventilation process)
Is calculated as

Further, the control device 50 further has a calculation program, which is based on the pressure (Pa) detected by the vacuum gauge 37 after a predetermined time when the warm-up process is executed. The time T required to remove water mixed in the oil of the rotary vacuum pump 30 is calculated. More specifically, when the oil in the oil rotary vacuum pump 30 contains water, the ability of the oil rotary vacuum pump 30 to evacuate is reduced. Therefore, when the warm-up process is executed, the vacuum gauge 37 after a predetermined time. The pressure (Pa) detected by the above is higher than the pressure (Pb) similarly detected in a state where water is not mixed in the oil of the oil rotary vacuum pump 30. The pressure obtained by removing the pressure (Pb) from the pressure (Pa) is a pressure increased due to the water mixed in the oil of the oil rotary vacuum pump 30. Further, the water that can be removed when one cycle of the warm-up process and the ventilation process is performed is substantially constant, and the pressure (Pc) that can reduce the pressure similarly measured during the warm-up process due to this amount of water. ) Is also constant. From these, the time T required to remove the water mixed in the oil of the oil rotary vacuum pump 30 is:
T (s) = (Pa−Pb) / Pc × (time required for one cycle of the warm-up process and the ventilation process)
Is calculated as

  In the vacuum packaging machine 10 configured as described above, the packaging bag is placed on the chamber base 13 so that the peripheral edge of the front opening of the packaging bag is placed on the upper side of the lower narrow pressure block 21, and the chamber base 14 is The upper surface opening of 13 is closed. When the operation panel 40 is operated to execute the vacuum packaging program, the control device 50 opens the vacuum valve 32 and operates the oil rotary vacuum pump 30 from the state where all the valves 32, 34, 35 and 39 are closed. Then, the inside of the chamber 12 is evacuated to make a negative pressure. When the pressure in the chamber 12 detected by the vacuum gauge 37 reaches 0.5 kPa (the degree of vacuum is 99.5%) as a predetermined pressure, the control device 50 opens the cylinder valve 39 and opens the upper part of the left and right lifting cylinders 26. The left and right support shafts 25 are raised by reducing the pressure in the space 26b, and the lower narrow pressure block 21 is raised to the raised position to be pressed by the upper narrow pressure block 22. In this state, when the control device 50 energizes the heater 23 from a power source (not shown) to generate heat, the peripheral edge of the opening of the packaging bag held by the lower and upper narrow pressure blocks 21 and 22 is heated. Welded and sealed. Thereafter, the control device 50 stops the operation of the oil rotary vacuum pump 30 and opens the second atmosphere introduction valve 35 and the first atmosphere introduction valve 34 in order, thereby introducing the atmosphere into the chamber 12. 12 is returned to atmospheric pressure, and air is introduced into the upper space 26b of the elevating cylinder 26, whereby the support shaft 25 is lowered by the spring 26d, and the lower narrow pressure block 21 is returned to the lowered position.

  In this vacuum packaging machine 10, when food or food with a lot of moisture is vacuum-packed, water is mixed into the oil of the oil rotary vacuum pump 30, and the oil rotary vacuum pump 30 sets the pressure in the chamber 12 to a predetermined pressure. It may not be possible to reduce the pressure to 0.5 kPa (vacuum degree is 99.5%). When water is mixed in the oil of the oil rotary vacuum pump 30 and the pressure in the chamber 12 cannot be evacuated to 0.5 kPa, the warm-up operation switch 41 of the operation panel 40 is turned on and the water draining operation program is turned on. Is executed.

  When the drainage operation program is started, the control device 50 opens the vacuum valve 32 and starts the warm-up process by operating the oil rotary vacuum pump 30 with the valves 34, 35 and 39 closed. . By the operation of the oil rotary vacuum pump 30, the inside of the chamber 12 is degassed to be negative pressure, the temperature of the oil in the oil rotary vacuum pump 30 rises, and the water contained in the oil rises in temperature and vaporizes. When the control device 50 executes the warm-up process, the control device 50 determines the time (ta) during which the pressure detected by the vacuum gauge 37 passes a predetermined pressure range (for example, 5 kPa to 1 kPa (95% to 99% in the degree of vacuum)). The water that can be removed when one cycle of the warm-up process and the ventilation process is performed compared to the time (tb) when the warm-up process is performed under the condition that water is not mixed in the oil of the oil rotary vacuum pump 30 From the time (tc) that can be reduced when the warm-up process is executed, the time T required to remove the water mixed in the oil of the oil rotary vacuum pump 30 is calculated. The control device 50 causes the display panel 42 to display the time from the calculated time until the water draining operation program ends.

  After the predetermined time has elapsed, the control device 50 starts the ventilation process by opening the second atmospheric introduction valve 35. By opening the second atmosphere introduction valve 35, outside air is introduced from the second pipe portion 33b of the atmosphere introduction pipe 33 into the oil rotary vacuum pump 30 that is evacuated and vacuumed in the chamber 12, and the warm-up process is performed. The water vaporized when going is released with the exhaust. Since the second pipe portion 33b of the atmosphere introduction pipe 33 has a small diameter, the pressure in the chamber 12 is maintained at about 5 kPa (vacuum degree is 95%) even when the atmosphere is introduced, and the chamber cover 14 is not opened.

  After a predetermined time has elapsed from the start of the ventilation process, the control device 50 closes the second atmosphere introduction valve 35 to end the ventilation process, and starts the warm-up process described above again. Note that each time the warm-up process is executed, the control device 50 executes a calculation program to calculate the time required to remove water mixed in the oil of the oil rotary vacuum pump 30, and drains water from the newly calculated time. The time until the operation program ends is displayed on the display panel 42.

  In addition, when the control device 50 executes the warming-up process, the pressure detected by the vacuum gauge 37 after a lapse of 30 seconds as a predetermined time is warmed up under the condition that water is not mixed in the oil of the oil rotary vacuum pump 30. It is determined whether or not the pressure is 0.5 kPa (99.5% in the degree of vacuum) as the same pressure as that when the process is executed. If the pressure is not 0.5 kPa (99.5% in the degree of vacuum), oil is determined. It is determined that the water mixed in the oil of the rotary vacuum pump 30 has not been removed, and the water drain operation program is controlled to continue.

  By repeatedly performing the warm-up process and the ventilation process alternately, water mixed in the oil of the oil rotary vacuum pump 30 is gradually removed. The control device 50 determines whether or not the pressure detected by the vacuum gauge 37 when the warm-up process is performed is 0.5 kPa (99.5% in vacuum), and is 0.5 kPa. Then, it is determined that the water mixed in the oil of the oil rotary vacuum pump 30 has been removed, and the water draining operation program is terminated. The control device 50 causes the display panel 42 to display the time when the drainage operation program is executed after the drainage operation program ends.

  In the vacuum packaging machine 10 configured as described above, the draining operation program of the oil rotary vacuum pump 30 opens the vacuum valve 32 and activates the oil rotary vacuum pump 30 so that the oil in the oil rotary vacuum pump 30 is turned into oil. The warming-up process for heating and vaporizing the mixed water, and the air introduction valve 35 is opened in a state where the oil rotary vacuum pump 30 is operated after the warming-up process, and the water vaporized when the warming-up process is performed is exhausted. The ventilation process to be discharged together with this is alternately performed. The water rotary operation of the oil rotary vacuum pump 30 not only releases the water vaporized by the warming-up process slightly with the exhaust during the warming-up process, but also releases the water vaporized by the warming-up process during the ventilation process. As compared with the conventional draining only in the warm-up process, water can be efficiently removed from the oil of the oil rotary vacuum pump 30 and the draining operation can be performed. The time can be shortened to 1/2 to 1/3 compared with the conventional warm-up process alone.

  The drainage operation program of the oil rotary vacuum pump 30 is configured to execute the warm-up process and the ventilation process alternately. When the warm-up process is executed, the pressure detected by the vacuum gauge 37 is a predetermined value. When the warming-up process is executed under the condition that water is not mixed in the oil of the oil rotary vacuum pump 30 during a time (ta) that passes through the pressure range (for example, 5 kPa to 1 kPa (95% to 99% in vacuum)). Compared to the time (tb) of the oil rotary vacuum pump from the time (tc) that can be reduced when the warm-up process is performed by the water that can be removed when one cycle of the warm-up process and the ventilation process is performed The time T required to remove the water mixed in 30 oil was calculated, and the time from the calculated time to the end of the water draining operation program was displayed on the display panel 42. Thereby, the drainage operation program can be executed until the water mixed in the oil of the oil rotary vacuum pump 30 is removed, and the time until the drainage operation program ends is displayed on the display panel 42. The operator can grasp the time during which the vacuum packaging machine 10 cannot be used for vacuum packaging, and can spend the time during which the operator cannot use the vacuum packaging machine for other work. In addition, the display panel 42 may display the elapsed time since the start of the water draining operation program. In such a case, the vacuum packaging machine 10 is allowed to perform the water draining operation, so that the vacuum packaging is performed. It is possible to inform other workers that it is not possible to perform the operation. In addition, when the other calculation program mentioned above is carried out, the same effect as the above can be obtained.

  Further, when the drainage operation program is executed, the control device 50 newly calculates the time required to remove the water mixed in the oil of the oil rotary vacuum pump 30 by the calculation program every time the warm-up process is executed. The time from the calculated time to the end of the drainage operation program is displayed. As a result, the time to completion predicted at the beginning of the drainage operation program that alternately executes the warm-up process and the ventilation process may vary depending on various conditions such as the temperature, but it is predicted every time the warm-up process is performed. Since the time from the calculated time to the end of the drainage operation program is displayed, it is possible to know the exact time at which the drainage operation program ends.

  When the drainage operation program is executed, the pressure detected by the vacuum gauge 37 when the warm-up process is executed is the pressure when the warm-up process is executed under the condition that water is not mixed in the oil of the oil rotary vacuum pump 30 It was detected that the water mixed in the oil of the oil rotary vacuum pump 30 was removed. By doing in this way, it came to be able to remove water reliably to the state where the water of the oil rotary vacuum pump 30 is not mixed with water. It should be noted that during the time when the pressure detected by the vacuum gauge 37 passes a predetermined pressure range (for example, 5 kPa to 1 kPa (95% to 99% in the degree of vacuum)), water is not mixed in the oil of the oil rotary vacuum pump 30. When it becomes the same as the time when the warm-up process is executed under the conditions, the time until the pressure detected by the vacuum gauge 37 reaches a predetermined value (for example, 1 kPa (99% in vacuum)) is the oil rotary vacuum pump. Even when it is detected that the water mixed in the oil of the oil rotary vacuum pump 30 has been removed when the time for the warm-up process is the same as the time when the water is not mixed in the oil 30 Good.

  The control device 50 displays the time when the drainage operation program is executed after the drainage operation program ends. Thereby, it became possible to grasp the amount of water mixed in the oil of the oil rotary vacuum pump 30 from the time when the drainage operation program was executed.

  In the vacuum packaging machine 10 configured as described above, the air is supplied to the oil rotary vacuum pump 30 from the second pipe portion 33b of the atmosphere introduction pipe 33 by opening the second atmosphere introduction valve 35 when the ventilation process is executed. However, the present invention is not limited to this, and when the ventilation process is executed, the first atmosphere introduction valve 34 is opened to perform oil rotation vacuum from the first pipe portion 33a of the atmosphere introduction pipe 33. Air may be introduced into the pump 30. In this case, the opening degree of the first atmospheric introduction valve 34 may be adjustable so that the pressure in the chamber 12 can be maintained at about 5 to 40 kPa (the degree of vacuum is 60% to 95%) as described above. .

  In the vacuum packaging machine 10 configured as described above, a nitrogen gas introduction pipe that extends in the horizontal direction at the front side of the lower narrow pressure block 21 and introduces nitrogen gas into the packaging bag at the front portion of the chamber base 13. 15 is provided. Note that a nitrogen gas supply pipe (not shown) led out from a nitrogen gas cylinder (not shown) is connected to the nitrogen gas introduction pipe 15 on the base end side. As shown in FIG. 5A, the nitrogen gas introduction tube 15 has a hole 15a formed in a lower portion slightly proximal to the distal end opening. By doing so, after the inside of the chamber 12 is degassed and negative pressure is applied, when the atmosphere is introduced into the chamber 12, the momentum of air entering from the tip opening of the nitrogen gas introduction pipe 15 is reduced, The food overflowing from the packaging bag is less likely to flow into the nitrogen gas introduction pipe 15. Further, as shown in FIG. 5 (b), the nitrogen gas introduction pipe 15 may be configured such that the front end opening side is directed downward, and even in this case, the food overflowing from the packaging bag is introduced into the nitrogen gas. It became difficult to flow into the tube 15. Note that a check valve may be provided at the tip opening of the nitrogen gas introduction pipe 15 in FIG. 5A, and even when this is done, the food material can be prevented from flowing into the nitrogen gas introduction pipe 15. .

 DESCRIPTION OF SYMBOLS 10 ... Vacuum packaging machine, 12 ... Chamber, 20 ... Sealing device (heating sealing device), 30 ... Oil rotary vacuum pump, 32 ... Vacuum valve, 35 ... Air introduction valve (2nd air introduction valve), 37 ... Vacuum Total.

Claims (5)

A chamber for storing a packaging bag containing a packaged item;
A sealing device that is provided in the chamber and seals the periphery of the opening of the packaging bag;
An oil rotary vacuum pump that evacuates the chamber to create a negative pressure;
A vacuuming circuit connecting the chamber and the oil rotary vacuum pump;
A vacuum valve that opens and closes the vacuum circuit, interposed in the vacuum circuit;
An air introduction circuit for introducing air into the oil rotary vacuum pump;
An air introduction valve for opening and closing the air introduction circuit interposed in the air introduction circuit;
A vacuum gauge for detecting the pressure in the chamber,
The oil rotary vacuum pump is controlled to operate so that the pressure in the chamber detected by the vacuum gauge becomes a predetermined value, and the packaging bag accommodated in the chamber is sealed by the sealing device. In a vacuum packaging machine that vacuum-packs packaging bags,
Opening the vacuum valve and operating the oil rotary vacuum pump to heat and vaporize water mixed in the oil of the oil rotary vacuum pump; and operating the oil rotary vacuum pump after the warm-up process In this state, the air introduction valve is opened, and the ventilation step of releasing the water vaporized when the warm-up step is performed together with the exhaust gas is alternately performed and mixed into the oil of the oil rotary vacuum pump. A vacuum packaging machine having a drainage operation program for removing water. The vacuum packaging machine according to claim 1,
When the warm-up process is executed, the time when the pressure detected by the vacuum gauge passes through a predetermined pressure range, the time until the pressure detected by the vacuum gauge reaches a predetermined value, or the vacuum after a predetermined time Based on the pressure detected by the meter, it has a calculation means for calculating the time required to remove the water mixed in the oil of the oil rotary vacuum pump, and the water draining operation program ends from the time calculated by this calculation means A vacuum packaging machine characterized in that the time until the start or the elapsed time since the start of the water draining operation program is displayed. The vacuum packaging machine according to claim 2,
Every time the warm-up process is executed, the time required for removing water mixed in the oil of the oil rotary vacuum pump is calculated by the calculating means, and the time from the calculated time to the end of the water draining operation program is calculated. A vacuum packaging machine characterized by displaying. In the vacuum packaging machine according to claim 2 or 3,
When the pressure detected by the vacuum gauge when the warm-up process is executed becomes the same pressure as the pressure when the warm-up process is executed under the condition that water is not mixed in the oil of the oil rotary vacuum pump. Further, it is detected that water mixed in the oil of the oil rotary vacuum pump is removed. In the vacuum packaging machine of any one of Claims 2-4,
A vacuum packaging machine characterized in that after the draining operation program is completed, the time when the draining operation program is executed is displayed.

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