JP7570802B2 - Air-rinsing device and air-rinsing method - Google Patents

Description

The present invention relates to an air-rinsing device and an air-rinsing method for cleaning the inside of a bottle.

A conventional method for removing foreign objects from a container is to blow gas into the container and use the gas to blow the foreign objects away.

For example, JP 2018-158294 A (Patent Document 1) discloses a foreign matter removal device in which a nozzle member facing the mouth of an inverted container is shifted from the axis of the container in one width direction. In this foreign matter removal device, the nozzle member is positioned as described above to form a sending side and a returning side of air flow within the container, which allows for good removal of foreign matter within the container.

In addition, WO 2015/147261 (Patent Document 2) discloses a cleaning method that includes a step of blowing air with a variable flow rate onto the inner surface of a container. In this cleaning method, components to be removed from the inner surface of the container can be removed as if "wiped" by blowing air with a variable flow rate, thereby improving the cleaning efficiency of the inner surface of the container.

JP 2018-158294 A International Publication No. 2015/147261

However, even when technologies such as those disclosed in Patent Documents 1 and 2 are adopted, there are still cases where removal of foreign matter from within a container is insufficient. Therefore, there is a need for an apparatus and method that can more effectively remove foreign matter from within a container.

The air rinse device of the present invention is an air rinse device capable of cleaning a container having a mouth while transporting it, and comprises a container holding part capable of holding and swinging the container with the mouth positioned on the lower side, a container transport part capable of transporting the container held in the container holding part, and a nozzle capable of injecting gas for a predetermined time into the inside of the container transported by the container transport part, and is characterized in that during at least a part of the predetermined time, the container holding part swings the container to either side from a state in which it is held, thereby controlling the tilt angle, which is the angle between the axis of the container connecting the center of the mouth and the center of the bottom side of the container, and an extension line of the nozzle, thereby controlling the positional relationship between the container and the nozzle, and controlling the tilt angle within a range where the extension line of the nozzle intersects with the bottom surface of the container during the predetermined time when the gas is sprayed .

Moreover, an air-rinse method according to the present invention is an air-rinse method in which a container having a mouth is transported in a state in which the mouth is positioned and held, and gas is injected into the inside of the container for a predetermined time, and the method controls the positional relationship between the container and the nozzle by rocking the container to either side from a held state during at least a part of the predetermined time, thereby controlling the tilt angle, which is the angle between the axis of the container connecting the center of the mouth and the center of the bottom side of the container, and an extension line of a nozzle from which the gas is injected, and controls the tilt angle within a range where the extension line of the nozzle intersects with the bottom surface of the container during the predetermined time when the gas is injected.

These configurations allow the interior of the container to be cleaned better than when the tilt angle is 0°. Also, the interior of the container can be cleaned well throughout its entirety. Furthermore, these configurations make it easy to implement a means for controlling the tilt angle, since rocking the container is often easier than rocking the nozzle, whose movement may be restricted by its connection to the gas source.

The following describes preferred embodiments of the present invention. However, the scope of the present invention is not limited to the preferred embodiments described below.

In one aspect, the air rinse device according to the present invention preferably changes its position alternately between a position in which the tilt angle is 0° and a position in which the tilt angle exceeds 0° during at least a portion of the predetermined time.

This configuration allows for better cleaning of the inside of the container.

Further features and advantages of the present invention will become more apparent from the following description of exemplary, non-limiting embodiments, which are given with reference to the drawings.

Schematic diagram of air rinse device Schematic diagram of the container holder and nozzle when holding the bottle in an upright position Schematic diagram of the container holder and nozzle when the bottle is held in an inverted position 1 is a schematic diagram of a container holder and a nozzle when a bottle is held in a swinging position. FIG. 13 is a diagram showing the difference in the positional relationship between the bottle and the nozzle when the bottle rocking angle is 0°. FIG. 13 is a diagram showing the difference in the positional relationship between the bottle and the nozzle when the bottle is rocked at an angle of 5°. FIG. 13 is a diagram showing the difference in the positional relationship between the bottle and the nozzle when the bottle is rocked at an angle of 10°. A diagram showing a filling facility equipped with an air rinse device. Schematic diagram of the bottle to be cleaned by the air rinse device

Embodiments of an air-rinse device and an air-rinse method according to the present invention will be described with reference to the drawings. Below, an example will be described in which the air-rinse device according to the present invention is applied to an air-rinse device 1 that cleans the inside of a PET bottle.

[Overall facility overview]
The air-rinse device 1 is disposed as a part of a filling equipment P that fills PET bottles B (an example of a container, hereinafter abbreviated as bottles B) with beverage products (FIG. 8). The filling equipment P includes, in order of process steps, a molding section M that molds bottles B from preforms, a sterilization section S that sterilizes the bottles B molded in the molding section M, an air-rinse device 1 that cleans the inside of the bottles B sterilized in the sterilization section S, and a filling section F that fills the bottles B cleaned by the air-rinse device 1 with beverage products. The filling equipment P is configured to perform each process of molding, sterilization, cleaning, and filling in succession by the above-mentioned sections.

[Bottle Overview]
The bottle B is a container whose main material is a thermoplastic resin such as polyethylene, polypropylene, or polyethylene terephthalate. The bottle B is molded by biaxial stretch blow molding of a preform obtained by injection molding of a thermoplastic resin. The capacity of the bottle B is, for example, 280 mL, 350 mL, 500 mL, 1 L, 2 L, etc., but is not particularly limited. The liquid to be filled in the bottle B is not particularly limited, and may be, for example, a soft drink (mineral water, coffee, cocoa, tea, carbonated drink, fruit juice, etc.), an alcoholic drink, a milk drink, or other beverage, a liquid food such as soup, or a liquid seasoning such as sauce or soy sauce.

As shown in Figure 9, bottle B is composed of a mouth Bs, which is an opening for inserting and removing contents, a shoulder that is continuous with the mouth Bs and gradually expands toward the bottom, a body Bw that is continuous with the shoulder, and a bottom surface Bb that forms the bottom of bottle B (Figure 9). Bottle B has a shape that is two-fold symmetrical about axis X that connects the center of mouth Bs and the center of bottom surface Bb (an example of the center of the bottom side of a container). Note that bottom surface Bb in this embodiment refers to the range (the range indicated by the arrow in Figure 9) that faces the plane when bottle B is placed on its own on a plane with mouth Bs positioned on the upper side and therefore cannot be seen from the side of bottle B.

[Configuration of the Air Rinse Device]
First, the configuration of the air rinse device 1 according to this embodiment will be described. In this embodiment, an example in which the capacity of the bottle B is 2 L will be described. The air rinse device 1 according to this embodiment has a structure in which a plurality of container holding parts 3 and nozzles 4 are provided on the periphery of a wheel 2 (an example of a container conveying part) ( FIG. 1 ). The wheel 2 rotates at a constant speed, and by this rotational motion, the bottle B received from the sterilization part S is conveyed to a position where it is handed over to the filling part F. The air rinse device 1 cleans the inside of the bottle B during this conveyance. In other words, the air rinse device 1 is a device that cleans the bottle B while conveying it.

The container holding unit 3 has a first arm 31 extending radially outward from the wheel 2, a second arm 32 rotatably supported by the first arm 31, and a clamp 33 supported by the second arm 32, and the clamp 33 can hold the mouth Bs of the bottle B (Fig. 2). The container holding unit 3 can hold the bottle B in an upright position with the mouth Bs located on the upper side (Fig. 2) and an inverted position with the mouth Bs located on the lower side (Fig. 3). The position can be changed between the upright position and the inverted position by rotating the second arm 32. In addition, the bottle B can be rocked by slightly rotating the second arm 32 in the inverted position, and the size of the rocking angle, which is the angle between the axis X of the bottle B and a vertical line, can be changed within a range in which the bottle B does not interfere with each component of the air rinse device 1 (Fig. 4).

The nozzle 4 is disposed integrally with the container holding part 3 on the periphery of the wheel 2. The nozzle 4 is a straight tube-shaped member disposed along the vertical direction. The nozzle 4 is connected to a compressed air supply unit (not shown), and air is continuously ejected from the nozzle 4. The positional relationship between the container holding part 3 and the nozzle 4 is set so that the nozzle 4 is inserted into the mouth part Bs of the bottle B when the bottle B is held in an inverted position (Figure 3). In addition, as described above, the bottle B can be swung by the rotation of the second arm 32, so the positional relationship between the bottle B and the nozzle 4 is controlled by the rotation of the second arm 32.

[Air rinsing method using an air rinsing device]
Next, an air-rinsing method according to the present embodiment, that is, an air-rinsing method using the air-rinsing device 1, will be described. Foreign matter may exist inside the bottle B that has reached the air-rinsing device 1 due to an upstream process. The air-rinsing method according to the present embodiment aims to remove such foreign matter. The air-rinsing method according to the present embodiment generally includes a step of changing the attitude of the bottle B received in an upright position from the sterilization section S to an inverted attitude, a step of injecting air (an example of gas) into the inverted bottle B, and causing foreign matter attached to the inner wall of the bottle B to separate from the inner wall by the turbulence formed by the air inside the bottle B, and discharging the foreign matter to the outside of the bottle B, and a step of changing the attitude of the inverted bottle B to an upright attitude and transferring it to the filling section F. Each of the above steps is performed while the bottle B is being transported by the rotational motion of the wheel 2.

The container holder 3 holds the bottle B that the air-rinse device 1 receives from the sterilization unit S in an upright position (Figure 2). The container holder 3 then changes the position of the bottle B to an inverted position (Figure 3). At this time, the nozzle 4 is inserted into the mouth Bs of the bottle B.

When the change in the position of the bottle B is complete, the nozzle 4 that continuously injects air is inserted into the mouth Bs of the bottle B, so that air is continuously injected into the inside of the bottle B. At this time, the flow rate of air injected from the nozzle 4 is equivalent to that of a known air-rinse device. Air is injected into the inside of the bottle B for a period of time (an example of a predetermined period of time) from immediately after the air-rinse device 1 changes the position of the bottle B received from the sterilization section S to an inverted position until immediately before the bottle B is changed to an upright position to be handed over to the filling section F.

While air is being ejected from the nozzle 4, the bottle B alternates between an inverted posture in which the axis X of the bottle B is aligned along the vertical direction (FIGS. 3 and 5) and a swinging posture in which the axis X is tilted 5° from the vertical direction (FIGS. 4 and 6). This change in posture is caused by the rotation of the second arm 32. As described above, the nozzle 4 is a straight tube-shaped member arranged along the vertical direction, so when the bottle B is in the inverted posture, the inclination angle θ, which is the angle between the extension line 41 of the nozzle 4 and the axis X, is 0°. Similarly, when the bottle B is in the swinging posture, the inclination angle θ is 5°. That is, the inverted posture is a posture in which the inclination angle θ is 0°, and the swinging posture is a posture in which the inclination angle θ exceeds 0°. Due to such swinging motion, the inclination angle θ exceeds 0° during a portion of the predetermined time during which air is ejected from the nozzle 4 (the time during which the bottle B is in the swinging posture). As is clear from the above, the rocking angle, which is the angle at which the bottle B is rocked in the rocking position, is the same as the tilt angle θ in the rocking position. In other words, the tilt angle θ is controlled by controlling the rocking angle by rotating the second arm 32.

More specifically, in the swinging position (Figure 4), the extension line 41 of the nozzle 4 intersects with the bottom surface Bb of the bottle B (Figure 6). As a result, most of the air ejected from the nozzle 4 forms a flow inside the bottle B that first hits the bottom surface Bb and then hits the body part Bw. The formation of such a flow makes it easier to remove foreign matter from the entire inside of the bottle B.

When bottle B approaches the end point of the air rinse device 1, the air injection stops. Then, the container holding unit 3 changes the position of bottle B from an inverted position (Figure 3) to an upright position (Figure 2). After that, bottle B is handed over to the filling unit F.

Below, we will explain the relationship between the positional relationship between the bottle and the nozzle and the efficiency of removing foreign matter from inside the bottle, using examples.

[Testing equipment and operation method]
A test device was used that includes a container holder capable of holding a bottle in an inverted position and a nozzle that can be inserted into the bottle held by the container holder. The container holder of this test device has the same structure and function as the second arm 32 and clamp 33 in the container holder 3 of the air-rinse device 1, and can rock the bottle held in an inverted position. The nozzle of this test device is connected to a compressed air supply unit, and has the same structure and function as the nozzle 4 of the air-rinse device 1.

[Evaluation method]
100 resin powder particles with an average particle size of 0.5 mm were placed in an empty bottle (volume 2 L). The bottle was held in the container holder of the test device, and air was injected from the nozzle of the test device to perform air rinsing. Pure water was poured into the bottle after air rinsing to wash the inside of the bottle, and the washing water after washing was filtered through a filter. Then, the number of resin powder particles captured in the filter was counted visually.

Example 1
Immediately after the air rinse started, the bottle was alternately changed in position between an inverted position with a rocking angle of 0° and an inverted position with a rocking angle of 5° every 0.5 seconds. After the rocking positions were taken 15 times, the bottle was maintained in the inverted position. After cleaning, the number of resin powder particles trapped in the filter was 7. In other words, the removal rate of resin powder was 93%.

Example 2
Immediately after the air rinse started, the bottle was alternately changed in position between an inverted position with a rocking angle of 0° and an inverted position with a rocking angle of 5° every 0.5 seconds. After the rocking position was taken twice, the bottle was maintained in the inverted position. After the cleaning, 16 pieces of resin powder were captured in the filter. In other words, the removal rate of resin powder was 84%.

Example 3
Immediately after the air rinse started, the bottle was alternately changed in position between an inverted position with a rocking angle of 0° and an inverted position with a rocking angle of 5° every 2.5 seconds. After the bottle was rocked twice, it was kept in the inverted position. After the cleaning, nine pieces of resin powder were trapped in the filter. In other words, the removal rate of the resin powder was 91%.
Example 4
Immediately after the air rinse started, the bottle was alternately changed in position between an inverted position with a rocking angle of 0° and an inverted position with a rocking angle of 10° every 2.5 seconds. After the bottle was rocked twice, it was kept in the inverted position. After the cleaning, 18 pieces of resin powder were trapped in the filter. In other words, the removal rate of resin powder was 82%.

Comparative Example
The bottle was held in an upside-down position and air-rinsed without being rocked. After cleaning, the number of resin particles trapped in the filter was 30. In other words, the removal rate of resin particles was 70%.

〔result〕
The test conditions and resin powder removal rates of Examples 1 to 4 and the Comparative Example are shown in Table 1. A higher removal rate was observed in each of Examples 1 to 4 compared to the Comparative Example in which shaking was not performed. In other words, it can be said that the inside of the bottle was cleaned better in Examples 1 to 4 in which shaking was performed compared to the Comparative Example in which shaking was not performed.

Furthermore, a comparison between Example 1 and Example 2 shows that, when the length of time each rocking position is maintained is the same, a larger number of rocking cycles results in better cleaning of the inside of the bottle. In addition, a comparison between Example 2 and Example 3 shows that, when the number of rocking cycles is the same, a longer time each rocking position is maintained results in better cleaning of the inside of the bottle. From these results, it is considered that a longer total time in the rocking position is more advantageous for cleaning.

Furthermore, by comparing Example 3 and Example 4, it can be said that, when the number of rocking movements and the length of time that each rocking posture is maintained are the same, the rocking angle of 5° cleans the inside of the bottle better than the rocking angle of 10°. As shown in Figures 5 to 7, when the rocking angle is 5°, the extension line 41 of the nozzle intersects with the bottom surface Bb of the bottle B, but when the rocking angle is 10°, the extension line 41 intersects with the body part Bw of the bottle B (Figures 6 and 7). Therefore, when the rocking angle is 5°, the air flow is likely to reach the entire inside of the bottle B, whereas when the rocking angle is 10°, the air flow is unlikely to reach the vicinity of the bottom surface Bb sufficiently. It is believed that such a difference in the behavior of the air flow inside the bottle B is reflected in the difference in the cleaning results between Example 3 and Example 4.

Other embodiments
Finally, other embodiments of the air-rinsing device and the air-rinsing method according to the present invention will be described. Note that the configurations disclosed in the following embodiments can be combined with the configurations disclosed in other embodiments as long as no contradiction occurs.

In the above embodiment, an example has been described in which the inclination angle θ between the axis X of the bottle B and the extension line 41 of the nozzle 4 is changed by controlling the swing angle at which the bottle B is held by rotating the second arm 32. However, the present invention is not limited to such a configuration, and the means for changing the inclination angle, which is the angle between the axis of the container and the extension line of the nozzle, is not particularly limited. For example, in the above example, the inclination angle is changed by moving the bottle B, but the inclination angle may also be changed by moving the nozzle. Note that as a driving mechanism for the means for changing these inclination angles, known mechanisms can be used, such as a method of providing a member (such as a rail) that guides the container holding part or the nozzle to swing, or a method of driving the container holding part or the nozzle by an actuator.

In the above embodiment, configurations in which the inclination angle θ is 5° and 10° have been described as examples. However, the present invention is not limited to such configurations, and the inclination angle according to the present invention is not particularly limited as long as it exceeds 0°. However, as in the above example in which the inclination angle θ is 5°, it is preferable that the inclination angle is selected within a range in which the extension line of the nozzle intersects with the bottom surface of the container. The range of inclination angles that satisfies such conditions is set appropriately depending on the various conditions related to the container, such as the content volume, shape, and dimensions, and the various conditions related to the nozzle, such as the shape, dimensions, and insertion position of the nozzle relative to the container.

In the above embodiment, as shown in FIG. 4, a configuration in which the bottle B is inclined radially outward from the wheel 2 has been described as an example. However, in the present invention, the direction in which the container is inclined is not particularly limited, and for example, the container may be inclined toward the container holding section, or inclined along the direction in which the container is transported. Regardless of the direction in which the container is inclined, the inclination angle in the present invention is defined as a positive value that represents the magnitude of the angle between the axis of the container and the extension of the nozzle.

In the above embodiment, a configuration in which the nozzle 4 is arranged along the vertical direction has been described as an example. However, the present invention is not limited to such a configuration, and the orientation of the nozzle according to the present invention is not particularly limited as long as it is within a range in which gas can be injected into the inside of a container held with the mouth portion arranged downward.

In the above embodiment, an example was described in which the container transport unit according to the present invention is provided as a wheel 2. However, the container transport unit according to the present invention is not limited to such a configuration, and may be a known transport means.

In the above embodiment, an example has been described in which the container holding part 3 has a clamp 33 capable of holding the mouth part Bs of the bottle B. However, the position at which the container holding part according to the present invention holds the container is not limited to the mouth part. For example, the container holding part according to the present invention may be capable of holding the body part of the container, or may be capable of holding the bottom surface of the container.

In the above embodiment, an example has been described in which the container is changed in position alternately between an inverted position and a swinging position. However, the present invention is not limited to such a configuration, and may be configured to assume a position in which the tilt angle exceeds 0° only once during the specified time that gas is ejected from the nozzle, or may be configured to assume only positions in which the tilt angle exceeds 0°. Furthermore, in the present invention, when the swinging position is assumed multiple times, the swing direction each time may be the same or different. For example, the container may be swung like a pendulum. Note that when the container is swung in multiple directions, the tilt angle for each time is defined as a positive value that represents the magnitude of the angle between the axis of the container and the extension of the nozzle in each time, regardless of the swing direction for each time.

In the above embodiment, the gas ejected from the nozzle 4 is air. However, without being limited to such a configuration, the gas ejected from the nozzle in the present invention is not particularly limited as long as it is not a gas that adversely affects the quality of the product filled in the container, and may be, for example, nitrogen, carbon dioxide, etc. Furthermore, the gas ejected from the nozzle in the present invention may be heated.

In the above embodiment, an example has been described in which air is continuously ejected from the nozzle 4. However, in the present invention, the gas ejected from the nozzle may be ejected intermittently. Thus, the nozzle may be configured to eject air only while the nozzle is facing the inside of the container, or may be configured to eject air from the nozzle for only a portion of the time the nozzle is facing the inside of the container.

In the above embodiment, a configuration in which bottle B has a two-fold symmetric shape has been described as an example. However, the present invention is not limited to such a configuration, and the bottle to be cleaned by the air rinse device of the present invention does not have to have rotational symmetry, and may have three-fold or more symmetry.

In the above embodiment, an example was described in which a bottle B having a mouth Bs, a body Bw, and a bottom surface Bb was to be cleaned. However, without being limited to such a configuration, the air rinse device according to the present invention can be used to clean any container as long as it is a container with a mouth. Therefore, the container to be cleaned by the air rinse device according to the present invention does not have to have a flat bottom, for example. In addition to the PET bottles exemplified above, examples of containers to be cleaned by the air rinse device according to the present invention include cans, bottles, bags, pouches, plastic containers, metal containers, and paper cartons.

In the above embodiment, an example has been described in which the bottom surface Bb of bottle B is defined as the area that faces the plane and cannot be seen from the side of bottle B when bottle B is placed on its own on a plane with mouth Bs on the upper side. However, without being limited to such a configuration, the bottom surface of the container according to the present invention can be an area having a certain range on the bottom side of the container. Therefore, the bottom surface of the container according to the present invention can be, for example, an area on the bottom side of the container, which is an area whose curvature is discontinuous with the body of the container. In this example, the container does not necessarily have to be able to stand on its own.

In the above embodiment, an example was described in which the air-rinsing device 1 is used in a filling equipment P that includes a molding section M, a sterilization section S, and a filling section F in addition to the air-rinsing device 1. However, without being limited to such a configuration, the air-rinsing device of the present invention may be used before or after any device as long as the devices are capable of transferring containers to each other. Therefore, the air-rinsing device of the present invention may be used in equipment having any of the other processes exemplified above.

As for other configurations, it should be understood that the embodiments disclosed in this specification are illustrative in all respects and that the scope of the present invention is not limited thereto. Those skilled in the art will easily understand that appropriate modifications are possible without departing from the spirit of the present invention. Therefore, other embodiments that are modified without departing from the spirit of the present invention are naturally included in the scope of the present invention.

The present invention can be used, for example, in filling equipment that fills PET bottles with beverage products, to clean the inside of the PET bottles before filling them with beverages.

1: Air rinse device 2: Wheel 3: Container holder 31: First arm 32: Second arm 33: Clamp 4: Nozzle 41: Extension of nozzle 4 B: Plastic bottle (bottle)
Bs: Mouth Bw: Body Bb: Bottom X: Axis θ: Inclination angle P: Filling equipment M: Molding section S: Sterilization section F: Filling section

Claims (3)

An air rinse device capable of cleaning a container having a mouth while conveying the container, comprising:
a container holding portion capable of holding and swinging the container with the mouth portion disposed below;
a container conveying unit capable of conveying the container held by the container holding unit;
a nozzle capable of injecting gas for a predetermined period of time into the container transported by the container transport unit;
During at least a portion of the predetermined time, the container holder swings the container from a held state to either side to control an inclination angle between an axis of the container that connects the center of the mouth and the center of the bottom side of the container and an extension line of the nozzle, thereby controlling a positional relationship between the container and the nozzle;
an air rinse device that controls the inclination angle within a range in which an extension line of the nozzle intersects with a bottom surface of the container during the specified time when the gas is sprayed . The air rinse device according to claim 1, which alternates between a position where the tilt angle is 0° and a position where the tilt angle exceeds 0° during at least a portion of the predetermined time. 1. An air rinsing method for injecting gas into a container having a mouth for a predetermined period of time while transporting the container in a state in which the mouth is positioned and held, the method comprising:
during at least a portion of the predetermined time, the container is swung to either side from a held state, thereby controlling the inclination angle between the axis of the container, which connects the center of the mouth and the center of the bottom side of the container, and an extension line of the nozzle from which the gas is ejected, thereby controlling the positional relationship between the container and the nozzle;
An air rinse method comprising: controlling the inclination angle within a range in which an extension line of the nozzle intersects with a bottom surface of the container during the specified time when the gas is sprayed .

Images