Vacuum packaging device and vacuum packaging method

Abstract

To provide a vacuum packaging device having high functionality.SOLUTION: A vacuum packaging device of an embodiment performs skin pack to an object to be packaged (a packaged object) and includes: a vacuum pump 42; a first chamber in which an opening is provided at a part and an interior may be decompressed by the vacuum pump 42 in a state that the packaged object is housed so as to face the opening; a heater block 31 for softening the skin film; and a control device 50 which controls the heater block 31 and the vacuum pump 42 so that the first chamber is decompressed by the vacuum pump 42 to cause the skin film facing the packaged object to adhere to the packaged object after the skin film is softened. The control device 50 causes the heater block 31 and the vacuum pump 42 to operate with timing shifted from each other so that operation times do not overlap with each other.SELECTED DRAWING: Figure 9

Description

[Technical field]

[0001] An embodiment of the present invention relates to a vacuum packaging device and a vacuum packaging method thereof. [Background technology]

[0002] Vacuum packaging is a packaging method in which the air is removed from a packaging bag containing the packaged product and then the bag is sealed. Vacuum packaging can prevent deterioration of the contents, and is widely used in the food and industrial fields, for example.

[0003] Skin pack packaging (hereinafter referred to as skin pack) has been used in recent years as one type of vacuum packaging. Skin packs are a form of packaging in which the packaged item, typically food, is sandwiched between a film and a backing paper, and the space between them is sealed with heat without any gaps, making it possible to completely seal, i.e., vacuum pack. Because skin packs are completely sealed, they suppress dripping, which is the moisture released from food during storage, and are widely used as a method to maintain the freshness of food and extend its expiration date.

[0004] A related technique involves a method of inserting a tray containing an item to be packaged into a mold having an opening on the upper surface thereof, an annular stepped surface at a position appropriately lower than the opening, a tray containing section recessed by the annular stepped surface, and a deaeration passage communicating with the annular stepped surface and the mold outer surface other than the annular stepped surface, and then inserting a skin film, which is a laminated film having an inner layer film that is in close contact with the tray and has high hot tack but no heat sealability to the inner surface of the tray when combined with the inner surface of the tray, and an outer layer film that is heated to a molding temperature and softened while being stretched three-dimensionally along the outer shape of the item to be packaged and that retains the three-dimensional shape when cooled, into the upper surface of the mold. a skin pack packaging method characterized in that the skin film is covered with a mold to seal the flat space surrounding the tray, then the flat space surrounding the tray is deaerated through the deaeration passage while the skin film is heated to the forming temperature and softened under the action of atmospheric pressure, stretched so as to drop from the opening, so as to be in close contact with the packaged item in the tray and strongly attached to the surface of the tray not occupied by the packaged item, and further strongly attached to at least half the width of the flange part of the tray, then the excess peripheral part of the skin film is cut off along the opening on the upper surface part of the mold, and then the skin pack package in which the tray containing the packaged item is wrapped with the skin film is removed from the mold. According to this method, a skin pack packaging bag can be obtained that is tightly attached to the surface of a tray made of a polystyrene foam pressure floating roller without the risk of cohesive failure, does not turn up under normal handling, maintains a closed state, can be easily opened, and is suitable for packaging foods heated in a microwave oven (see Patent Document 1 below).

[0005] A related technique is a skin pack package manufacturing apparatus that produces a skin pack package by placing an item to be packaged between a base material and a heated film and degassing the space between the base material and the film, the skin pack package manufacturing apparatus being characterized by comprising: a heating section that heats the film; a film conveying section that conveys the film from the heating section; and a degassing section that is located downstream of the heating section in the conveying direction of the film and degassses the space between the base material and the film while the item to be packaged is placed between the heated film and the base material. According to this apparatus, after conveying the film that has been subjected to the heating process in the heating section, when a degassing process for producing a skin pack package is performed in the degassing section, a film for producing a next skin pack package can be present in the heating section. This makes it possible to perform the heating process in the heating section and the degassing process in the degassing section at the same time, and there is no need to keep the heating section on standby until the degassing process in the degassing section is completely completed. Therefore, a plurality of the skin pack packages can be produced more efficiently (see Patent Document 2 below). [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2013-189243 A [Patent Document 2] JP 2014-136605 A Summary of the Invention [Problem to be solved by the invention]

[0007] The problem to be solved by the invention is to provide a highly functional vacuum packaging device. [Means for solving the problem]

[0008] A vacuum packaging device of an embodiment is a vacuum packaging device that performs skin packing on an item to be packaged, and includes a vacuum pump, a first chamber having an opening in one portion and an internal pressure that can be reduced by the vacuum pump when the item to be packaged is contained opposite the opening, a heater for softening a skin film, and a control unit that controls the heater and the vacuum pump so that after the skin film has been softened, the vacuum pump reduces the pressure inside the first chamber, thereby causing the skin film facing the item to adhere closely to the item to be packaged, and the control unit operates the heater and the vacuum pump at staggered times so that their operating times do not overlap. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a perspective view of a vacuum packaging device according to a first embodiment in a raised state. [Diagram 2] FIG. 2 is a front view of the vacuum packaging device according to the first embodiment in a raised state. [Diagram 3] FIG. 2 is a side view of the vacuum packaging device according to the first embodiment in a raised state. [Figure 4] FIG. 1 is a perspective view of a vacuum packaging device according to a first embodiment in a lowered state. [Diagram 5] FIG. 2 is a front view of the vacuum packaging device according to the first embodiment in a lowered state. [Figure 6] FIG. 2 is a side view of the vacuum packaging device according to the first embodiment in a lowered state. [Figure 7] 1 is a schematic diagram showing an internal configuration of a vacuum packaging device according to a first embodiment. FIG. [Figure 8] FIG. 2 is a schematic view showing an annular cutter according to the first embodiment. [Figure 9] FIG. 2 is a block diagram showing a control system of the vacuum packaging device according to the first embodiment. [Figure 10] 4 is a time chart for explaining the operation of the vacuum packaging device according to the first embodiment. [Figure 11]FIG. 13 is a diagram illustrating the blocking of the lower chamber by a skin film. [Figure 12] FIG. 13 is a diagram illustrating the blocking of the lower chamber by a skin film. [Figure 13] FIG. 13 is a diagram for explaining the lowering of the upper chamber. [Figure 14] FIG. 13 is a diagram for explaining the reduction in pressure in the upper and lower chambers. [Figure 15] FIG. 13 is a diagram for explaining cutting of a skin film by an annular cutter. [Figure 16] 11 is a diagram for explaining melting of a skin film by a cut heater. FIG. [Figure 17] 13 is a diagram illustrating the raising of the upper chamber and the removal of the skin pack package. FIG. [Figure 18] 6 is a time chart for explaining the operation of a vacuum packaging device according to a comparative example. [Figure 19] FIG. 6 is a schematic view showing an annular cutter according to a second embodiment. [Figure 20] FIG. 11 is a block diagram showing a control system of a vacuum packaging device according to a second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] <First embodiment> Hereinafter, the details of the embodiments of the present invention will be described with reference to the drawings. In this specification and the drawings, components having substantially the same functional configurations are denoted by the same reference numerals, and duplicated explanations will be omitted.

[0011] (Overall composition) First, the overall configuration of the vacuum packaging device according to this embodiment will be described. Figs. 1 to 3 are perspective, front, and side views of the vacuum packaging device according to this embodiment in an elevated state, and Figs. 4 to 6 are perspective, front, and side views of the vacuum packaging device in a lowered state. Hereinafter, the front side of the vacuum packaging device will be referred to as the front, the back side as the back, and the direction perpendicular to the front-rear direction and the up-down direction as the left-right direction. Figs. 3 and 6 show the left side of the vacuum packaging device. Figs. 1 to 6 also show a state in which a tray T and packaged items W, which will be described later, are set in the vacuum packaging device 1.

[0012] As shown in Figs. 1 to 4, the vacuum packaging device 1 for skin packs according to this embodiment includes a substantially rectangular housing 10 incorporating a vacuum pump and the like, the details of which will be described later. The housing 10 has an opening 201 formed on the top surface thereof, thereby providing a substantially box-shaped lower chamber 20 that is open at the top. The lower chamber 20 can be set (placed) with packaged items W and trays T to be skin-packed using a skin film F on its bottom surface. In this embodiment, the lower chamber 20 is formed to a size that allows two packaged items W and two trays T to be set therein, making it possible to skin-pack two packaged items W at the same time.

[0013] The vacuum packaging device 1 of this embodiment can package a variety of items W, including meats such as fish, beef, pork, chicken, etc., vegetables, as well as foods such as cooked foods, processed foods, and frozen foods, and industrial products such as substrates; in other words, any item that can be skin-packed is acceptable.

[0014] The skin film F is a laminated film made of a resin material such as polyethylene, and is preferably one having barrier properties. When the skin film F is heated at a predetermined temperature or higher (softening temperature) for a predetermined time, it softens, and at least one surface, specifically the surface facing the packaged item W, becomes capable of adhering to the packaged item W and the tray T. In this embodiment, a skin film F having a softening temperature of 130° C. and a heating time of about 10 seconds is used. Examples of such films include skin pack films manufactured by Sumitomo Bakelite Co., Ltd.

[0015] The tray T is a flat cardboard on which the packaged item W is placed, and preferably has a barrier property similar to that of the skin film F. From the viewpoints of cost and heat insulation, the tray T may be made of a resin material such as polystyrene foam, but is preferably a paper tray. An example of such a tray is Green Flat (registered trademark) manufactured by Toppan Printing Co., Ltd. The tray T may be, for example, 170 mm x 260 mm in size.

[0016] An operation panel 11 is provided on the front of the housing 10, and a user of the vacuum packaging device 1 operates this operation panel 11 to start and end the skin pack. The operation panel 11 may be provided with, for example, a power switch for turning the power of the vacuum packaging device 1 ON / OFF, a start button for starting the skin pack, setting buttons for setting vacuum conditions such as the vacuum degree and decompression wait time of the vacuum pump 42 (see FIG. 9), and heating conditions such as the heating temperature and heating time of the various heaters, and a display such as a 7-segment display for displaying the setting values ​​changed by the setting switches. The operation panel 11 may be configured as a touch panel display on which the above-mentioned various buttons can be operated.

[0017] Plate-shaped frames 12 are provided extending in the up-down direction at both left and right ends of the upper surface of the rear side of the housing 10. Support frames 121 with notches at the upper ends are provided on the inner side surfaces of the upper ends of the two frames 12. The two support frames 121 support the rotation shaft of the film roll FR, on which the skin film F is wound so as to be unwound, through the notches to support the film roll FR so as to rotate relatively.

[0018] Above the housing 10 and between the two frames 12, a substantially box-shaped upper chamber 30 having a heater block 31 described later on its underside is provided. The upper chamber 30 is formed to have a size in the front-rear and left-right directions corresponding to the size of the lower chamber 20, and as shown in Figs. 2, 3, 5, and 6, both ends in the left-right direction are rotatably supported on one end of a plate-like oscillating frame 13 formed to be long. The other end of the oscillating frame 13 is rotatably supported on the inner side surface of the frame 12. As a result, the upper chamber 30 can be oscillated up and down around the oscillating frame 13 while being supported by it. The upper chamber 30 can be oscillated from the uppermost position shown in Fig. 3 to the lowermost position shown in Fig. 5, and is configured so that its upper surface remains horizontal during the oscillation.

[0019] The upper chamber 30 positioned at the lowest position can airtightly close the opening 201 of the lower chamber 20, and in this state the upper chamber 30 and the lower chamber 20 are sealed from each other. In other words, the lower chamber 20 and the upper chamber 30 function as lids for each other. A handle 301 is provided on the front of the upper chamber 30, and the user can easily raise and lower the upper chamber 30 by gripping the handle. The upper chamber 30 may be raised and lowered manually, or may be raised and lowered by a control device 50 (see FIG. 9) described later that operates a drive device such as a motor in response to the operation of the operation panel 11.

[0020] Next, the internal configuration of the lower chamber 20 and the upper chamber 30 will be described. Fig. 7 is a schematic cross-sectional view taken along line AA shown in Fig. 3. Fig. 8 is a schematic view showing an annular cutter according to this embodiment. Fig. 8 (a) is a schematic plan view of the annular cutter 32, and (b) is a schematic side view thereof.

[0021] As shown in Fig. 7, the lower chamber 20 has a tray stand 21 provided on the upper surface of its bottom wall portion 202. The tray stand 21 has an annular groove 211 that is generally rectangular in plan view and into which an annular cutter 32, described later, can be uniformly inserted. One annular groove 211 is provided for one packaged item W, and therefore, in this embodiment in which two packaged items W can be skin-packed, two annular grooves 211 are formed spaced apart in the left-right direction. The annular groove 211 functions as a receiving portion that receives the annular cutter 32 for cutting a skin film F, described later.

[0022] The portion of the tray stand 21 surrounded by the annular groove 211 forms a placement portion 212 on which the tray T is placed. The placement portion 212 is preferably formed to have substantially the same shape as the tray T or a larger size, particularly a slightly larger size. When setting the tray T in the vacuum packaging device 1, the user simply places the tray T on this placement portion 212, and the tray T can be set in the vacuum packaging device 1 reliably and easily without making a mistake in the setting position.

[0023] The upper chamber 30 has two openings formed in the bottom wall 302, which are arranged in parallel in the left-right direction, and a heater block 31 is disposed in each of the openings. The heater block 31 is formed in a generally rectangular flat plate shape in a plan view, and generates heat when its operation is controlled (energized) by a control device 50, which will be described later. The heater block 31 can soften the skin film F by generating heat while in contact with the skin film F. The heater block 31 is provided with a plurality of air intake holes 311, and when the skin film F comes into contact with the heater block 31 and the pressure inside the upper chamber 30 is reduced, the skin film F can be attached to the heater block 31.

[0024] In this embodiment, the lower end of a columnar connecting member 312 is connected to the upper surface of the heater block 31. The connecting member 312 passes through a support plate 33 (described later) and has its upper end connected to an upper wall portion 303 of the upper chamber 30, thereby supporting the heater block 31 within the upper chamber 30. Note that the method of supporting the heater block 31 is not limited to this, and it is sufficient that the heater block 31 is provided in the upper chamber 30 so as not to fall off.

[0025] When the upper chamber 30 shown in Fig. 7 is in the highest raised state, the tip (lower end) of the annular cutter 32 is located in each of the two gaps 304 formed between the two heater blocks 31 and the bottom wall portion 302. The annular cutter 32 cuts the skin film F, and as shown in Fig. 8(a), is formed in an annular shape that is generally rectangular in plan view so as to be able to pass through the gap 304 without contact. In other words, it is formed in approximately the same shape as the gap 304 and the annular groove 211. Also, as shown in Fig. 8(b), the lower end of the annular cutter 32 serves as a cutting edge, and in this embodiment, a piercing saw blade 321 is uniformly formed.

[0026] An upper end of the annular cutter 32 is connected to a support plate 33, and the support plate 33 is connected to a tip of a piston rod 341 in a cylinder 34. The cylinder 34 moves the piston rod 341 back and forth by supplying compressed fluid such as compressed air from a compressor (not shown) that is driven and controlled by a control device 50 (described later). Therefore, the annular cutter 32 can move back and forth in the vertical direction by the cylinder 34 via the support plate 33.

[0027] A plurality of spiral coil springs 35 are provided around the annular cutter 32, for example near the four corners, and a pin 36 is provided in each hollow portion of the plurality of coil springs 35 to allow the coil springs 35 to expand and contract and prevent bending. The lower end of the pin 36 is connected to the bottom wall portion 302, and the upper end forms a head 361 with an expanded diameter. The pin 36 is inserted through the support plate 33 so that the support plate 33 is located below the head 361, and the upper end of the coil spring 35 abuts against the lower surface of the support plate 33. The lower end of the coil spring 35 abuts against the bottom wall portion 302.

[0028] Therefore, when the annular cutter 32 and the support plate 33 move down, the piston rod 341 moves downward against the restoring force of the coil spring 35. On the other hand, when the downward movement of the piston rod 341 is released, that is, when the air pressure or oil pressure is no longer supplied to the cylinder 34, the restoring force of the coil spring 35 pushes the annular cutter 32 and the support plate 33 back to their original reference positions (the positions shown in FIG. 7).

[0029] Next, a control system of the vacuum packaging device 1 according to this embodiment will be described. Fig. 9 is a block diagram showing the control system of the vacuum packaging device according to this embodiment.

[0030] As shown in FIG. 9, the above-mentioned control device 50 includes a CPU (Central Processing Unit) 501 that controls the vacuum packaging device 1, a storage device 502 that includes a memory used as a working area for the CPU 501 and stores various programs for the vacuum packaging device 1 and setting values ​​for various vacuum packaging conditions (decompression waiting time, vacuum degree, heater temperature, softening time, etc.), and an IF (Interface) circuit 503 that performs input / output processing of each signal.

[0031] The control device 50 is connected to the above-mentioned operation panel 11, heater block 31, cylinder 34 (cylinder compressor), as well as the limit switch 37 of the upper chamber 30, the temperature sensor 38, the locking mechanism 41, the vacuum pump 42, the upper vacuum solenoid valve 43, the upper atmosphere introduction valve 44, the lower vacuum solenoid valve 45, the lower atmosphere introduction valve 46, the cut heater 47, and the alarm unit 48 via an IF circuit 503 so as to be able to input signals from each device and / or output control signals for controlling the operation of each device.

[0032] The limit switch 37 here detects whether the upper chamber 30 is open or closed. The temperature sensor 38 detects the temperature of the heater block 31. The locking mechanism 41 locks the upper chamber 30 when the upper chamber 30 is positioned at the lowest position and closes the opening 201 of the lower chamber 20, making it impossible to separate, i.e., impossible to lift. The locking mechanism 41 is configured to maintain the lock in a non-energized state and to release the lock when electricity is applied. Any suitable locking method may be used, for example a solenoid lock in a latch mechanism.

[0033] The vacuum pump 42 is connected to intake passages that communicate with the lower chamber 20 and the upper chamber 30, and reduces the pressure inside the two chambers via these passages.

[0034] The upper vacuum solenoid valve 43 is provided in the intake flow passage between the upper chamber 30 and the vacuum pump 42, and allows / disables the fluid connection between the upper chamber 30 and the vacuum pump 42. The upper atmosphere introduction valve 44 is a solenoid valve provided between the upper chamber 30 and the upper vacuum solenoid valve 43 via a vacuum release branch flow passage provided in the intake flow passage, and by opening this solenoid valve, the pressure inside the upper chamber 30 can be returned to atmospheric pressure from a reduced pressure state.

[0035] The lower vacuum solenoid valve 45 is provided in the intake passage between the lower chamber 20 and the vacuum pump 42, and allows / disables fluid connection between the lower chamber 20 and the vacuum pump 42. The lower atmosphere introduction valve 46 is a solenoid valve provided between the lower chamber 20 and the lower vacuum solenoid valve 45 via a vacuum release branch passage provided in the intake passage, and by opening this solenoid valve, the inside of the lower chamber 20 can be returned to atmospheric pressure from a reduced pressure state.

[0036] In this embodiment, the upper vacuum solenoid valve 43 and the lower vacuum solenoid valve 45 open the flow paths when energized, and the upper atmosphere introduction valve 44 and the lower atmosphere introduction valve 46 close the flow paths when energized.

[0037] The cut heater 47 heats the skin film F unwound from the film roll FR with high temperature contact terminals, pinching it from above and below, and melts it down with pressure and heat. Note that the method is not limited to melting, and it may be configured to cut with a cutter blade. The notification unit 48 notifies the user that the skin pack has finished. The notification unit 48 is preferably configured as a buzzer, but may also be configured as a lamp that flashes.

[0038] (device operation) Next, the operation of the vacuum packaging device 1 according to this embodiment will be described. The vacuum packaging device 1 according to this embodiment is set to execute a skin pack process with reduced rated power consumption as a default process operation, which will be described below. FIG. 10 is a timing chart showing the operation of the vacuum packaging device according to this embodiment, and FIGS. 11 to 17 are diagrams for explaining the operation. FIGS. 11, 13 to 15, and 17 are cross-sectional views corresponding to the line AA shown in FIG. 3, and FIGS. 12 and 16 show the vacuum packaging device 1 as viewed from the left side. Here, it is assumed that various vacuum packaging conditions, heater temperature, etc. are set to predetermined set values ​​by the manager of the vacuum packaging device 1 in advance. It is also assumed that a tray T on which the packaged item W is placed is set in advance on the placement section 212 of the tray table 21.

[0039] As shown in Fig. 10, first, when the power is turned on, the heater block 31 starts heating (S1). At this time, the control device 50 obtains the detection result of the temperature sensor 38, and controls the heater to repeatedly turn on and off so that the temperature is maintained when the heater block 31 reaches the set temperature. After heating, as shown in Figs. 11 and 12, the user unwinds the skin film F from the film roll FR, pulls it downward, and then pulls it forward (forward), closing the opening 201 of the lower chamber 20 with the pulled skin film F. This causes the skin film F and the packaged item W to face each other.

[0040] After closing, as shown in Fig. 13, the user lowers the upper chamber 30 to cover the opening 201 of the lower chamber 20 with the upper chamber 30, specifically by contacting it with the skin film F interposed therebetween (S2). At this time, as shown in Fig. 10, the contact between the upper chamber 30 and the lower chamber 20 activates the limit switch 37, and in response, the lock mechanism 41 operates to prevent the upper chamber 30 from moving upward from the lower chamber 20, that is, to lock the upper chamber 30 to maintain the contact state.

[0041] After the upper chamber 30 descends, as shown in Fig. 10, the upper atmosphere introduction valve 44 and the lower atmosphere introduction valve 46 are closed, the upper vacuum solenoid valve 43 is opened, and the pressure inside the upper chamber 30 is reduced by the vacuum pump 42 (S3). In response to this reduction in pressure, the skin film F is attracted to the intake hole 311 and adheres to the heater block 31. This adhesion causes the skin film F to soften due to the heat of the heater block 31, and the lower surface becomes capable of adhering to the packaged item W and the tray T. At this time, the heater block 31 is turned OFF prior to the reduction in pressure, and the skin film F is softened by the residual heat.

[0042] For this reason, when pressure reduction in the upper chamber 30 starts, the temperature of the heater block 31 is preferably higher than the temperature at which the skin film F softens (130°C in this embodiment), for example, a temperature slightly higher, such as several degrees Celsius to several tens of degrees Celsius. Therefore, it is preferable that the target temperature of the heater block 31 is set in advance to at least a temperature higher than the softening temperature. The heating time of the skin film F may be, for example, about 10 seconds.

[0043] After the pressure in the upper chamber 30 is reduced, the lower vacuum solenoid valve 45 is opened, and the pressure in the lower chamber 20 is reduced (S4), as shown in Fig. 10. Note that the pressure reduction in the lower chamber 20 may be performed simultaneously with the pressure reduction in the upper chamber 30.

[0044] After the pressure reduction in the lower chamber 20 starts, the upper vacuum solenoid valve 43 is closed and the upper atmosphere introduction valve 44 is opened while the pressure reduction in the lower chamber 20 is strengthened (S5). At this time, as shown in Fig. 14, as the pressure reduction progresses, the softened skin film F gradually falls downward as the air between the packaged item W and the tray T and the skin film F is degassed, and as the degassing progresses further, the skin film F is airtightly and securely attached to the surfaces of the packaged item W, the tray T, and the tray base 21. The pressure reduction in the lower chamber 20 and the pressure reduction / atmosphere introduction in the upper chamber 30 as described above, i.e., steps S3 to S5, may take a total of, for example, about 45 seconds from start to finish.

[0045] After the pressure in the lower chamber 20 is reduced, the piston rod 341 is moved downward by the cylinder 34, and the annular cutter 32 and the bottom wall 302 are moved downward via the support plate 33 and the pin 36. As the downward movement continues, the lower surface of the bottom wall 302 first comes into contact with the upper surface of the tray table 21 via the skin film F. This causes the bottom wall 302 to function as a presser that suppresses the movement of the skin film F. In this state, when the piston rod 341 is moved further downward, the bottom wall 302 cannot move any further, so the support plate 33 and the annular cutter 32 move downward against the restoring force of the coil spring 35. This movement pushes the annular cutter 32 into the annular groove 211, as shown in FIG. 15. As a result, the skin film F on the annular groove 211, that is, the excess skin film F (excess film portion) protruding from the packaged item W and the tray T, is cut while being pressed by the bottom wall 302 (S6). This cut makes it possible to separate the skin film F covering the packaged item W and the tray T from the excess skin film F.

[0046] 10, before the cylinder 34 is operated, the vacuum pump 42 is stopped and the lower vacuum solenoid valve 45 is closed. Even if the vacuum pump 42 is stopped, the reduced pressure state in the lower chamber 20 is maintained to some extent, and the skin film F is in a state of being firmly attached to the packaged article W and the tray T, so that the film can be cut without any problem.

[0047] 16, the cut heaters 47 arranged to sandwich the skin film F from above and below are heated, and the contact terminals move toward the skin film F to come into contact with the skin film F and melt it down. The moving cut heater 47 may be arranged on either the top or bottom of the skin film F and move toward the skin film F, and the other side may be configured as a receiving portion against which the cut heater 47 is pressed via the skin film F. The cut heaters 47 may be moved manually by the user, or may be controlled by the control device 50 using a solenoid or the like.

[0048] After the skin film F is cut, the lower atmosphere introduction valve 46 is opened, the supply of compressed fluid to the cylinder 34 and the cut heater 47 are stopped, and the lock mechanism 41 is released (S7), as shown in Fig. 10. When the supply of compressed fluid to the cylinder 34 is stopped, the support plate 33 and the annular cutter 32 are returned upward by the restoring force of the coil spring 35 and positioned at the reference position, as shown in Fig. 17. The cutting of the skin film F and the introduction of atmosphere into the lower chamber 20 as described above, that is, steps S6 and S7, may take a total of about 5 seconds from start to finish, for example.

[0049] By opening the lower atmosphere introduction valve 46, the pressure inside the lower chamber 20 is returned to atmospheric pressure, the lock is released, and then the buzzer sounds from the alarm unit 48, and the upper chamber 30 becomes capable of rising (S8). Here, as shown in FIG. 17, the user raises the upper chamber 30 to the reference position (highest position). The upper chamber 30 may be configured to be constantly biased upward by an elastic body such as a spring (not shown). In this way, the upper chamber 30 can be automatically raised by the biasing force of the elastic body after the lock is released. At this time, the heater block 31 is at a temperature lower than the target temperature, so that heating is performed again to skin-pack the next packaged item W, as shown in FIG. 10. Also, since the upper chamber 30 rises, the limit switch 37 is turned OFF.

[0050] After the upper chamber 30 has been raised, the user can remove the skin-packed package SP, in which the skin-packed packaged item W has been sealed, from the lower chamber 20, and remove the remaining part of the cut skin film F that remains in the lower chamber 20 to return it to the state shown in Figure 7, and then set it together with the tray T in the lower chamber 20 to skin-pack the next packaged item W.

[0051] FIG. 18 is a time chart for explaining the operation of a vacuum packaging device according to a comparative example. As shown in FIG. 18, this comparative example differs from the skin packing process according to the present embodiment in that the heater block 31 is constantly turned on and off to maintain the target temperature (here, 130° C.). In addition, the vacuum pump 42 continues to operate until air is introduced into the lower chamber 20. For this reason, in the skin packing process according to the present embodiment, compared to the skin packing process according to the comparative example, the heating of the heater plate, which consumes a large amount of power, is stopped when the pressure inside the upper chamber 30 is reduced in step S3, and thus, it is avoided that the heater plate and the vacuum pump, which also consume a large amount of power, are operated simultaneously. In addition, the vacuum pump 42 is stopped when the film is cut in step S6, thereby realizing a further reduction in power consumption.

[0052] According to the present embodiment described above, it is possible to reduce the operating time of the heater block 31 and the vacuum pump 42, which consume a lot of power, and to avoid simultaneous operation by shifting the operating timing of these, including the cut heater 47, which consumes a lot of power. Therefore, it is possible to realize high functionality, such as reducing rated power consumption and realizing low costs. Note that it is preferable to be able to switch between processes on the operation panel 11 so that the skin pack process according to the comparative example can also be performed in some cases.

[0053] In this embodiment, a compressor (not shown) is used to operate the cylinder 34. However, this is not limited to this, and the cylinder 34 may be operated by utilizing the pressure reduction effect of the vacuum pump 42.

[0054] <Second embodiment> Fig. 19 is a schematic diagram showing the annular cutter according to this embodiment. Fig. 20 is a block diagram showing a control system of the vacuum packaging device according to this embodiment.

[0055] As shown in Figures 19 and 20, the vacuum packaging device 1A of this embodiment differs from the vacuum packaging device 1 of the first embodiment in that it has an annular cutter 32A instead of an annular cutter 32, the tip of which is not serrated, but has a single blade 322 that extends uniformly in the horizontal direction, and in that the cutter body 320 of the annular cutter 32A is provided with an annular cutter heater 60 whose heating can be controlled by the control device 50.

[0056] The cutter heater 60 is provided uniformly around the outer periphery of the cutter body 320, so that heat can be transferred evenly and reliably to the cutting edge. In addition, when the vertical length of the annular cutter 32A is, for example, 40 mm, the cutter heater 60 is preferably attached to the cutter body 320 so that its lower surface is positioned about 5 mm above the cutting edge of the annular cutter 32A. By setting the distance between the cutting edge and the cutter heater 60 in this manner, heat can be transferred well to the cutting edge, and cutting of the skin film F can be prevented from being hindered. This distance is preferably at least equal to or greater than the thickness of the skin film F.

[0057] The saw blade 321, such as the annular cutter 32 according to the first embodiment, requires a lot of time and effort to manufacture because the blade is made one by one, resulting in a very high cost. In addition, because it is a piercing type, its sharpness deteriorates quickly. However, the annular cutter 32A according to the present embodiment does not require processing of the cutting edge into a saw blade, and only a single blade 322 is required, so that it is extremely easy to manufacture and can reduce costs. In addition, the deterioration of the sharpness is naturally slower than that of a saw blade. Furthermore, because the annular cutter 32 is heated by the cutter heater 60, it becomes easier to cut the skin film F, and the deterioration of the sharpness can be further delayed. Therefore, by providing the annular cutter 32A and / or the cutter heater 60, the vacuum packaging device 1A can have higher functionality than the conventional one.

[0058] The cutter heater 60 may be any type capable of heating the annular cutter 32A, such as a rubber heater with a built-in nichrome wire, a band heater, or a cartridge heater. The cutter heater 60 may be set to any suitable temperature, but it does not have to be as high as the target temperature of the heater block 31, and is preferably set in the range of 60°C to 100°C. Depending on the type of skin film F used, the tip of the annular cutter 32A may not be a single-edged tip, but may have a flat shape, i.e., no blade may be formed. In that case, the skin film F may be melted and cut by the heat of the cutter heater 60 and the pressing pressure of the annular cutter 32A.

[0059] In this embodiment, the annular cutter 32A has been described as having a single-edged cutting edge, but this is not limited to this and may be a double-edged cutting edge. Also, the cutter heater 60 has been described as being uniformly in contact with the outer periphery of the annular cutter 32A, but a plurality of cutter heaters 60 may be provided at regular intervals along the outer periphery.

[0060] The embodiments of the present invention are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included in the scope and spirit of the invention, and are included in the scope of the invention and its equivalents described in the claims. [Explanation of symbols]

[0061] 1,1A vacuum packaging equipment 20 Lower chamber (first chamber) 201 Aperture 30 Upper chamber (second chamber) 31 Heater block (heater) 32, 32A Annular cutter (cutter) 42 Vacuum Pump 50 Control device (control unit) 60 Cutter heater (heater) F Skin Film W Packaged item

Claims

1. A vacuum packaging device that performs skin packing on an item to be packaged, A vacuum pump; a first chamber having an opening in a portion thereof and capable of being decompressed by the vacuum pump when the packaged item is accommodated in the first chamber so as to face the opening; a heater for softening the skin film; a control unit that controls the heater and the vacuum pump so that, after the skin film is softened, the inside of the first chamber is depressurized by the vacuum pump, thereby causing the skin film facing the packaged item to come into close contact with the packaged item; Equipped with The control unit operates the heater and the vacuum pump at different times so that their operation times do not overlap. A vacuum packaging device characterized by:

2. a second chamber whose inside can be decompressed by the vacuum pump; the heater is provided in the second chamber, and softens the skin film while the inside of the second chamber is depressurized by the vacuum pump; The control unit heats the heater to reach a predetermined set temperature prior to reducing the pressure in the second chamber, and stops heating the heater until skin packing of the packaged items is completed.

2. The vacuum packaging device according to claim 1.

3. The method further includes a cutter for cutting an excess film portion around the packaged item in the skin film that has been softened and is covering the packaged item, The control unit stops the vacuum pump before the cutter cuts the skin film.

2. The vacuum packaging device according to claim 1.

4. The heater is set at a temperature higher than the target temperature at which the skin film will soften.

4. The vacuum packaging device according to claim 1, wherein the vacuum packaging device is a packaging material that is rotatable relative to the container.

5. A vacuum packaging method for skin-packing an item to be packaged, comprising the steps of: A skin film for skin-packing the packaged item is heated by a heater, and the skin film is softened so as to be able to adhere closely to the packaged item; A first chamber has an opening in a portion thereof, and the opening is closed with the skin film to place the skin film and the packaged item opposite the opening. After the heater is stopped, the pressure in the first chamber is reduced by a vacuum pump, and the skin film is brought into close contact with the packaged item. A vacuum packaging method comprising the steps of:

Images