JP7133170B2 - Ultrasonic film packaging machine - Google Patents

Description

The present invention relates to an apparatus for packaging an object to be packaged such as a cake (hereinafter simply referred to as "cake") with a plastic film for food packaging (hereinafter simply referred to as "film") using a welding horn that vibrates ultrasonically. .

As a packaging form of a cake, a packaging form in which the outer peripheral surface of the cake is wrapped with a film is known from Patent Documents 1 to 4, etc., and devices for this packaging are marketed by multiple manufacturers under the name of cake packaging machines and the like. provided.

A conventional cake wrapping machine uses the stickiness of the fresh cream and dough used in the cake to hold the film wrapped around the cake, and then cuts the wrapped film held by the cake using an electric heat fusion sealing method. Carrying out the packaging process.

However, in the above-mentioned cake packaging, the film is temporarily held on the outer peripheral side of the cake by utilizing the viscosity of the cake. The film cannot be held using the viscosity of the cake. For this reason, there has been a problem that the conventional cake packaging machine cannot package the frozen cake neatly or neatly.

In addition, since conventional film packaging machines such as cake packaging machines use an electric heater or an electric heating plate for thermal fusion sealing, the adhesion between films tends to be too strong. When the outside diameter of the heater is reduced, there is a problem that the durability of the heater is lowered.

Furthermore, in the conventional packaging method, there is a problem that the melted film adheres to the heating element, and in order to solve this problem, there is a difficulty that the peelable surface must be treated using a Teflon (registered trademark) material. . In addition, there is a problem that temperature control of the heater is troublesome due to differences in preheating and ambient temperature, and smoke and odor generated by the heater heating during film melting and cutting are undesirable from the standpoint of working environment.

JP-A-10-16915 Japanese Utility Model Laid-Open No. 6-80666 JP-A-1-308713 JP-A-63-203517

The present invention is a film packaging apparatus using ultrasonic waves which solves the problem that cake film packaging by a conventional film packaging machine that uses an electric heater or an electric heating plate for sealing and cutting the film has poor tearability of the packaging film. The task is to provide

The configuration of the ultrasonic film packaging apparatus of the present invention, which has been made for the purpose of solving the above problems, comprises a conveyor for placing and conveying an object to be packaged such as a cake (hereinafter simply referred to as "cake"); A film supply mechanism arranged in a direction intersecting the conveying direction of the conveyor and supplying wrapping film around the cake on the conveyor, and a film supply mechanism sandwiching the conveyor and advancing and retreating in a direction substantially orthogonal to the conveying direction of the conveyor. An ultrasonic film welding device comprising, on a base, a welding horn that vibrates ultrasonically and is supported by an advancing/retreating mechanism, and a film welding portion formed by an anvil facing the welding horn, wherein the welding horn sandwiches the film. At least one of the abutment surface at the tip of the anvil and the abutment surface at the tip of the anvil is formed to have different left and right widths in the length direction of the abutment surface. The distal end of the contact surface is formed to have a curved plane cross section, for example, an arc shape.

The lateral width of the contact surface of the welding horn or anvil is formed by a wide width portion and a narrow width portion along the length direction of the contact surface. Since the narrow width portion can have a smaller welding strength than the wide portion, the welded portion having the weaker welding strength can be easily torn when tearing apart the film in which the cake is wrapped.

In the present invention, instead of changing the lateral width of the contact surface of the anvil in the longitudinal direction of the contact surface, the lateral width of the contact surface of the welding horn is changed in the longitudinal direction. may be formed. In the present invention, changing the lateral width of the contact surface in the length direction of the contact surface is applied to both the contact surfaces of the welding horn and the anvil, or to one of the contact surfaces. It is optional to apply.

The welding horn and the anvil of the packaging apparatus of the present invention move toward and away from each other. In order for the two members to move forward and backward facing each other, the supporting portion of the welding horn and the supporting portion of the anvil are supported by a slide forward/backward mechanism. In the sliding advance/retreat mechanism, each of the sliding bases, each having the two supporting parts, floats on the base of the packaging machine via a spring, rubber, or other member having an elastic function. placed in a (floating) state.

This is because the contact line between the front end surface (contact surface) of the welding horn and the front end surface (contact surface) of the anvil facing the front end surface (contact surface) is in close contact with the front end surface (contact surface). be. By the way, if there is an error (manufacturing error, assembly error, etc.) in the sliding movement mechanism of the welding horn and the anvil, the contact line (welding line) cannot be in close contact with the entire length unless it is in a floating state, It causes poor adhesion of the film.

In the above, it is sufficient that both of the sliding bases of the welding horn and the anvil supporting portion, or either one of the sliding bases, be placed in the floating state.

The advancing speed of the welding horn and the anvil, which face each other toward the film by the action of the sliding advance/retreat mechanism in order to weld the cake-wrapped film, is determined by the welding point (contact point) where the film is welded. is controlled so that it becomes slower as it approaches .
In addition, the speed of the conveyer is controlled so that the speed at which the cake is conveyed decreases as the rear end of the cake, viewed in the feed direction, approaches the welding horn and the anvil facing each other.
With this control, when packaging a rectangular cake, for example, the film can be welded to the cake in a substantially close contact state, so that neat and neat packaging can be achieved without wasting the film. By the way, when the cake is conveyed at a constant speed, the film wrapping the rear end of the cake is excessively pulled out (fed out) and left behind the rear end of the cake. It is formed in the shape and does not look good. On the other hand, in order to seal and cut the film surrounding a square cake with an electric heater, it is necessary to extend the film excessively so that the electric heater does not come close to the cake. The reality was that neat film packaging was not possible.

A packaging film to be welded is sandwiched between the welding horn and the anvil which are ultrasonically vibrated by advancing the welding horn and the anvil face-to-face, and the film is welded and cut by the action of the welding horn and the anvil which are in contact with each other. In the packaging apparatus, since the lateral widths of the abutment surfaces of the welding horn and the anvil tip are formed to have different widths in the lengthwise direction of the abutment surfaces, the welded portion of the film is welded along the lengthwise direction. You can make a difference in strength. Therefore, the film can be easily torn from the welded portion on the side where the welding strength is weak.

BRIEF DESCRIPTION OF THE DRAWINGS The top view which shows schematic structure of the principal part of the ultrasonic film packaging apparatus which concerns on this invention. FIG. 2 is a perspective view schematically showing the shapes and correspondences of the welding horn and the anvil in the ultrasonic film packaging apparatus of FIG. 1; The perspective view which showed typically the positional relationship of the cake and film in the ultrasonic film packaging apparatus of FIG. FIG. 2 is an enlarged view taken along the line AA in FIG. 1 for explaining the outline of the positional relationship between the welding horn and the anvil in the ultrasonic film packaging apparatus of FIG. 1; FIG. 5 is an enlarged view of the anvil in FIG. 4 as viewed from line BB. Fig. 6 is a right side view of Fig. 5; FIG. 6 is a plan view of FIG. 5;

Next, an example of an ultrasonic film packaging device according to the present invention (hereinafter also simply referred to as the device of the present invention) will be described with reference to the drawings.

FIG. 1 is a plan view showing an example of the schematic configuration of the device of the present invention. In FIG. 1, 1 is arranged at the approximate center of the base MB which is the base of the apparatus of the present invention in order to transport an object of film packaging such as cake C (hereinafter referred to as cake C) from the left side to the right side of FIG. One example is a conveyor using a flat belt. The conveyer 1 may use a belt, chain, or the like other than the flat belt.

Reference numerals 2 and 3 denote a first film F1 and a second film F2 placed in the vicinity of the front side (left side in FIG. 1) of the base MB when viewed from the feeding direction of the conveyor 1 so as to sandwich the conveyor 1. are a first film roll and a second film roll, respectively.

Reference numerals 4 and 5 guide the feeding of the first film F1 and the second film F2 from the first film roll 2 and the second film roll 3, respectively, and support the feeding of the film toward the feed direction side of the transport conveyor 1. They are a first film delivery section and a second film delivery section mainly formed of roll groups such as guide rolls 4a, 5a, guide rolls 4c, 5c, and drive rolls 4b, 5b. The first film roll 2, the second film roll 3, the first film delivery section 4, and the second film delivery section 5 form an example of a film supply mechanism. Incidentally, 4d and 5d are film pressers arranged in the vicinity of the first film roll 2 and the second film roll 3, respectively.

6 and 7 are arranged on the downstream side of the first film delivery section 4 and the second film delivery section 5 so as to face each other with the transport conveyor 1 interposed therebetween, and advance and retreat in a direction perpendicular to the transport direction of the transport conveyor 1. It is a welding horn and anvil which are ultrasonically vibrated and are arranged so as to form a welding/cutting portion of the first film F1 and the second film F2 (see FIG. 2).

The welding horn 6 and the anvil 7 forming the welding cut portions of the first film F1 and the second film F2 are arranged on the base MB of the apparatus of the present invention in the manner shown in FIG. 4 as an example. The rear end of the welding horn 6 is coupled to the tip of an ultrasonic transducer 6a, and the ultrasonic transducer 6a is supported by a support portion 6b. The rear end of the anvil 7 is supported by a support portion 7a.

The two support portions 6b and 7a are arranged on a slide base 6c and a slide base 7b, respectively, and these slide bases 6c and 7b are mounted on base mounts 6d and 7c, respectively. . The slide bases 6c and 7b are formed to move forward and backward (in the direction of the arrow in FIG. 4) on the base mounts 6d and 7c by the driving force of cylinders, feed screws, etc. (not shown).

The base mounts 6d and 7c are supported in a floating state on the base MB by floating members 8 and 9, respectively, which are selected from elastic members such as rubber insulators and springs. This is because the abutment surface 61 at the tip of the welding horn 6 and the abutment surface 71 at the tip of the anvil 7 are in close contact with each other over the entire area even if there is an error such as a manufacturing error or an assembly error between them. This is to ensure that

In the apparatus of the present invention provided with the welding horn 6 and the anvil 7 arranged on the base MB as described above, the cake C and the first film F1 and the second film F2 for wrapping the cake C are arranged relative to the cake C. is schematically shown in FIG.

1, the cake C1 placed on the front side of the conveyor 1 (on the left side of the conveyor 1 in FIG. 1) is conveyed by the conveyor 1 to the position of the cake C2. During this transportation, before the cake C1 passes through the film welding/cutting section by the welding horn 6 and the anvil 7, the first film F1 is delivered from the first film delivery section 4 and the second film delivery section 5, respectively. , the second film F2 is fed forward from the front surface of the cake C1 with respect to the conveying direction of the cake C1.

The welding horn 6 and the anvil 7 are advanced to the first film F1 and the second film F2 that have been fed, and the first film F1 and the second film F2 are welded We1, and protrudes from the welding We1. A portion of the first film F1 and the second film F2 are cut, and the positional relationship between the first film F1 and the second film F2 welded We1 to the cake C1 is set to the state shown in FIG. 3(a). When the first welding We1 and cutting are completed, the welding horn 6 and the anvil 7 are retracted and returned to their original positions. In the following, We1 is also referred to as a first welded portion.

After the first welding We1, when the welding horn 6 and the anvil 7 return to their original positions, the cake C1 is further conveyed by the conveyer 1, and the first film F1 and the second film F1 integrated by the first welding We1 are separated. The film F2 takes the form shown in FIG. 3(b). Then, the welding horn 6 and the anvil 7 advance again to the first film F1 and the second film F2, and the first film F1 and the second film F2 are subjected to the second welding We2 on the rear end side of the cake C2. Then, the first film F1 and the second film F2 are cut (see cake C2 in FIG. 1). In the following, We2 is also referred to as a second welded portion.
In the above description, the feeding speed of the first film F1 and the second film F2 is substantially synchronized with the feeding speed of the cake C2. Control so that the delivery speed is low. On the other hand, the welding horn 6 and the anvil 7 advancing for the second welding We2 are also controlled so that their speed decreases as they approach the welding portion. As a result, the first film F1 and the second film F2 can be second welded We2 at a position closer to the rear end of the cake C2.

After the second welding We2 is completed and the first film F1 and the second film F2 are cut, the cake C2 wrapped with the first film F1 and the second film F2 is further conveyed to the conveyer 1 shown in FIG. The state of cake C3, which is drawn on the right end side and is completed with film packaging, is reached. In the cake C3 on the transport conveyor 1, Fp is the wrapping film (see FIG. 1).

As described above, the cake C is transported to the positions of the first film delivery section 4 and the second film delivery section 5 by the transport conveyor 1 . Then, the first film F1 and the second film F2 are applied and conveyed as they are, and the first film F1 and the second film F2 form the first weld We1 by the action of the welding horn 6 and the anvil 7 at the welding/cutting portion. The film packaging of the cake C is completed by applying the second welding We2. In the present invention, the welded/cut portion of the film is provided with a technical device unique to the present invention. This point will be described below with reference to FIG.

The action of welding and cutting the film by the welding horn 6 and the anvil 7 forming the welding/cutting portion is as follows. That is, the contact surface 61 at the tip of the welding horn 6 and the contact surface 71 at the tip of the anvil 7 sandwich the two sheets of the first film F1 and the second film F2, and in this state, the welding horn 6 is ultrasonically vibrated. Then, the portions sandwiched between the contact surfaces 61 and 71 of the welding horn 6 and the tip of the anvil 7 of the two first and second films F1 and F2 generate heat and are melted and integrated (adhered). When the tip of the anvil 7 further sharpened from the state is pressed against the welding horn 6, the melted and integrated first film F1 and second film F2 are cut at that portion. The tip of the abutment surface 71 of the anvil 7 has a substantially arcuate planar cross section.

The welding action of the two sheets of the first film F1 and the second film F2 by the welding horn 6 and the anvil 7 is that of the portion sandwiched between the contact surface 61 of the welding horn 6 and the contact surface 71 of the anvil 7. It is obtained by melting the insides of the first film F1 and the second film F2 to integrate the first film F1 and the second film F2.

In this case, the welding state of the first film F1 and the second film F2 is such that the contact area (lateral width of the contact surface) between the contact surface 61 of the welding horn 6 and the contact surface 71 of the anvil 7 is The total length L of the contact surfaces 61 and 71 in the length direction (hereinbelow, the lengths of the two welded portions We1 and We2 of the first film F1 and the second film F2 are also referred to as welded lines L for convenience of explanation). Then, the weld strength becomes substantially uniform in the length direction of the weld line L. As shown in FIG. The welding strength is large when the width of the welding line L (the width in the direction perpendicular to the welding line L = lateral width) is large, but is small when the width of the welding line L is narrow. A difference in welding strength occurs.
In the above description, for convenience of explanation, the total length L in the length direction of the contact surfaces 61 and 71 and the welding line L between the first film F1 and the second film F2 are denoted by the same reference numeral L. However, in reality, The length of the contact surfaces 61 and 71 is longer than the vertical width of the first film F1 and the second film F2 to be ultrasonically welded (substantially the same as the length of the welding line L). An anvil 7 is formed.

Therefore, in the present invention, the lateral width of the weld line L in the first weld portion We1 and the second weld portion We2 is changed in the longitudinal direction of the weld line L so as to change the welding strength in the longitudinal direction of the weld portion. made it Specifically, in the anvil 7 shown in FIG. 5, the length L of the contact surface 71 is formed to be about 20 to 30% of the total length of the contact surface 71 with a small width (narrow width w1), and the remaining width is 80 to 70%. %, so that the weld line L of each of the first welded portion We1 and the second welded portion We2 is increased in strength in the longitudinal direction. I made a difference. As a result, the side of the two welded portions We1 and We2 where the welding strength is low (the side with the small width w1) is the starting point of tearing, and the wrapping film Fp can be easily and neatly teared.

In the present invention, in order to control the welding strength of the welded portions We1 and We2 in the manner described above, the following method is employed as an example. 5 is a front view of the contact surface 71 of the anvil 7. In this example, the total length of the contact surface 71 (the total length L of the anvil 7 in the height direction in FIG. 5) is about 20% above. The contact surface 71a with the narrow width w1 is formed with the left-right width up to the contact surface 71b with the wide width w2 with the remaining 80% of the length. The ratio of the lateral widths of the contact surface 71a with the narrow width w1 and the contact surface 71b with the wide width w2 is approximately 1:2, but the ratio of the lateral widths is not limited to this.
The ratio of the length of the contact surface 71a with the narrow width w1 and the contact surface 71b with the wide width w2 to the total length L of the contact surface 71 is also an example, and the present invention is not limited to this ratio. not something. In the present invention, the ratio of the wide contact surface 71b and the narrow contact surface 71a is, for example, between 9.5 and 6.0:0.5 and 4.0, or any ratio other than the above values. can be set to

In the above example, the planar cross-sectional shapes of the two contact surfaces 71a and 71b with the narrow width w1 and the wide width w2 are also substantially arcuate (see FIG. 7). 7, the contact surface 71a with the narrow width w1 has an acute apex angle, and the contact surface 71b with the wide width w2 has an acute apex angle. becomes an obtuse angle.
When the two contact surfaces 71a and 71b of the anvil 7 having different left and right widths are configured as in the above example, the contact surface 61 of the welding horn 6, although not shown, has a substantially uniform left and right width. The one formed on the contact surface 61 is sufficient.

In the present invention, the contact surface 61 of the welding horn 6 may have a lateral width difference along the welding line L, similar to the lateral width of the contact surface 71 of the anvil 7 . In the present invention, it is optional to apply the configuration in which the left and right widths of the contact surfaces 61 and 71 are different to one or both of the contact surfaces 61 and 71 .

As in the above-described embodiment, the anvil 7 having a left-right width difference over the entire length in the length direction of the contact surface 71 of the anvil 7 and the wrapping film Fp ultrasonically welded by the welding horn 6 have a narrow width of the welding line L. It can be easily cleaved at the w1 site.
Incidentally, in the conventional film packaging that is welded using an electric heating wire or an electric heating plate, the welding strength could not be changed along the welding line L, so the easy tearing property of the film packaging like the present invention was not possible. you can't get it.

The above description is about an example of film packaging by a film packaging machine using two films, the first film F1 and the second film F2, for packaging the cake C. can be applied to the welding horn 6 and the anvil 7 of a known ultrasonic film packaging device for packaging the cake C, the same effect as the above example can be obtained.

Since the present invention is as described above, the film packaging of objects such as frozen cakes, in which the film cannot be temporarily held due to the viscosity of the packaging object, can be neatly and neatly packaged without wasting the film. It can be carried out. It goes without saying that the present invention can be applied not only to the frozen cakes of the above examples, but also to the film packaging of room temperature cakes, other frozen foods, normal temperature foods, and the like.

C cake (frozen cake, packaging object)
C1 to C3 Cake MB on transport conveyor 1 Base F1 of packaging apparatus of the present invention First film F2 Second film 1 Transport conveyor 2 First film roll 3 Second film roll 4 First film delivery section 5 Second film delivery Part 6 Welding horn 6a Ultrasonic vibrator 6b Supporting part 6c Sliding base 6d Base stand 7 Anvil 7a Supporting part 7b Sliding base 7c Base stand 61 Contact surface 71 of welding horn 6 Contact surface 71a of anvil 7 Narrow width w1 contact surface 71b wide width w2 contact surfaces 8 and 9 floating member We1 first weld (first weld portion)
We2 Second welding (second welding part)
Fp Wrapping complete film L Total length of contact surface 71 of anvil 7 (welded lines of welded portions We1 and We2)

Claims (8)

A conveyor for placing and conveying an object to be wrapped such as a cake, and a film supply mechanism arranged in a direction intersecting the conveying direction of the conveyor and supplying a wrapping film around the object on the conveyor. A film is welded and cut by an ultrasonically vibrating welding horn supported by an advancing/retreating mechanism so as to sandwich the conveyor and advance and retreat in a direction substantially perpendicular to the conveying direction of the conveyor, and an anvil facing the welding horn. , wherein at least one of the contact surfaces at the tip of the welding horn and the anvil sandwiching the film is located at one end in the length direction of the contact surface. An ultrasonic film packaging device, wherein the lateral width is smaller than the lateral width of the other end , so that the adhesive strength of the one end is smaller than the adhesive strength of the other end . The lateral width of one end in the lengthwise direction of the contact surface and the lateral width of the other end are formed on the contact surface of the anvil by a narrow width portion and a wide width portion, and the contact surface of the welding horn is formed on the contact surface of the anvil. 2. An ultrasonic film packaging device according to claim 1, wherein the film is formed to have a uniform lateral width in the longitudinal direction . 2. The front end of said welding horn is a contact surface having a narrow width portion and a wide width portion instead of the contact surface formed at the narrow width portion and the wide width portion of the front end of said anvil. of ultrasonic film packaging equipment. The ratio of the wide part and the narrow part of the welding line formed on the film is in the range of 9.5 to 6.0:0.5 to 4.0. The ultrasonic film packaging device according to any one of claims 1 to 3, which is formed so that: The ultrasonic film packaging device according to any one of claims 1 to 4, wherein the width of the wide portion of the contact surface is at least 2 when the width of the narrow portion is 1. The ultrasonic film packaging according to any one of claims 1 to 5, wherein at least one or both of said advancing/retracting mechanisms respectively supporting said welding horn and said anvil are installed on a base in a floating state. Device. The conveyor on which the object is placed conveys the object at a predetermined speed when the front half of the object passes through the welded portion formed by the welding horn and the anvil. The ultrasonic film packaging apparatus according to any one of claims 1 to 6, which is controlled so that the object is conveyed at a speed lower than the predetermined speed. 8. The ultrasonic film packaging apparatus according to claim 7, wherein the welding horn and the anvil advancing to the welding portion are controlled so that advancing speed becomes slower as the welding portion is approached.

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