CN112693646A

CN112693646A - Bag firing system for bag firing applicator assembly

Info

Publication number: CN112693646A
Application number: CN202011137489.9A
Authority: CN
Inventors: S.布里奥斯基
Original assignee: FLSmidth AS
Current assignee: FLSmidth AS
Priority date: 2019-10-22
Filing date: 2020-10-22
Publication date: 2021-04-23

Abstract

A bag firing system for a bag firing applicator assembly for feeding a sewing valve bag to a rotating wrapper; the sewing valve bag includes a valve selectively movable between a closed configuration and an open configuration; a bag firing system configured for being supplied with bags having the valves in a closed configuration and for firing bags having the valves in an open configuration to a filling nozzle of the rotating wrapper; the bag shooting system includes: a receiving device configured for receiving a bag; a firing device configured for being supplied with the pouches by the receiving device and for firing the pouches to the filling nozzles of the rotating wrapper; opening valve means acting on the valve before the bag is detached from the shooting means; a guide means extending from the firing means towards the rotating wrapper and acting on the pouch after it exits from the firing means, the guide means being configured for guiding the pouch towards the rotating wrapper and for keeping the valve in an open configuration.

Description

Bag firing system for bag firing applicator assembly

Technical Field

The present invention relates to the field of filling valve bags with powdered or granular products, in particular cement for the cement industry, building materials, fertilizers and chemical products. In particular, the present invention relates to a bag applicator assembly for use with "rotating" wrappers. As is known, the rotary wrapper comprises a plurality of filling stations arranged circumferentially alongside one another and supported by a rotating structure, so that during rotation each filling station cyclically faces the bag applicator assembly to receive an empty bag. The present invention relates to a bag applicator assembly for a rotary wrapper wherein valve bags are supplied from the bag applicator assembly to a rotating filling station not by a robotic arm but by a bag firing device configured for firing bags onto the rotating filling station. More in detail, the invention relates to a bag shooting system comprising the above-mentioned bag shooting device. The present invention also relates to a bag firing system for feeding a sewn valve bag to a rotating wrapper and a bag firing applicator assembly including the bag firing system.

Background

A special component called a wrapper is used in the cement industry. In particular, the wrapper assembly is an automated machine configured for handling and filling valve bags. A valve bag is a bag, i.e. a rectangular paper or plastic tube, having a back side and a front side (typically providing content indication), wherein each side is defined by two opposite long sides, two opposite short sides and two opposite ends closed by glue or stitching. Since the valve bags are stored in a compressed stack, it is immediately possible to see which side is the long side. In a valve bag, valves are provided at the corners between the long and short sides, the valves being in the form of open folded edge portions of the bag itself. In view of the above-described configuration, the valve is considered closed when the bag is in a compressed state (i.e., face-to-face compressed), even if the folded edge portions of the opposing faces are not physically constrained to one another. Since the valve bag is fed to the wrapper assembly in this pressurized state, it is important to open the valve in advance prior to the filling operation. In practice, in the wrapper assembly, the filling of the valve bag is performed by coupling the open valve of the bag with the filling nozzle of the filling station.

The wrapper components may be divided into two groups. A first type of wrapper assembly may be defined as a fixed wrapper assembly and comprises a wrapper provided with a plurality of fixed filling stations, which are typically arranged alongside each other in a linear/straight direction. The supply of the valve bag to the filling station is performed by a bag applicator assembly comprising a bag applicator device (typically a bag applicator arm) extending along a linear/straight guide from the opened valve device to the filling station and vice versa. A second type of wrapper assembly may be referred to as a "rotating" wrapper assembly and comprises a wrapper provided with a plurality of filling stations arranged alongside one another (generally in the circumferential direction) in a moving configuration. In particular, in a rotating wrapper, the filling stations are supported by a rotating structure such that during rotation of the structure, each filling station cyclically confronts a bag applicator assembly configured for supplying empty bags to the rotating filling station. Further, the bag-applicator assembly used to rotate the wrapper assembly may also be divided into two sub-groups. A first bag applicator assembly includes an applicator arm configured for picking up bags to release the bags to a rotating filling nozzle. The second bag applicator assembly is called a shooting bag applicator assembly and comprises a bag shooting system, i.e. a system comprising a shooting device configured for shooting a bag with a valve in an open configuration into a filling nozzle rotated by the front of the bag shooting device itself. As is known, the gunbag applicator assembly can provide a higher throughput (in terms of bags per hour) than the armbag applicator assembly. Today, however, when the bag is a sewn valve bag, it is not recommended that the bag firing applicator assembly be used to rotate the wrapper assembly. By the term "sewn valve bag" according to the present invention we mean a bag that is typically made by hand or low level mechanization, so that the bag has large dimensional tolerances (5% or greater). Furthermore, sewn valve bags are typically made of thin plastic materials and therefore have little rigidity. Also, when the bags are stored in a compressed stack, they may exhibit incorrect alignment and may be provided with undesirable bends. In particular, bag firing applicator assemblies are not proposed today for sewn valve bags for the following reasons. As mentioned above, the sewn valve bag is made of a thin plastic material and thus has low rigidity. Due to this low rigidity, the presence of the sewing band can close the pockets and eventually lead to shape defects (these pockets are made manually), during the shooting from the applicator to the filling nozzle, trajectory deviations from the desired straight trajectory occur. Due to this deviation of trajectory, some bags missed the coupling with the filling nozzle. Furthermore, in addition to this problem of trajectory deviation, the valves of a sewn valve bag tend to close elastically during shooting.

As the demand for automatic bag application of sewn valve bags continues to increase, there is a need today to implement a new bag firing system for a bag firing applicator assembly that can be used in a rotating wrapper assembly with high reliability even in the case of sewn valve bags.

Disclosure of Invention

It is, therefore, a primary object of the present invention to provide a bag firing system for a bag firing applicator assembly of a rotating wrapper assembly that overcomes the disadvantages of the prior art. In particular, the main scope of the present invention is to realize a bag firing system which is also adapted to ensure high efficiency in case of feeding sewn valve bags. As previously mentioned, a valve bag is a tubular member closed at opposite ends by folding and sewing. At the corners between the long sides and the sewn short sides, valves are provided in the form of open folds.

In view of the following considerations, it is important to define another structural line or direction that defines a sewn valve bag. This line may be defined as the lower or inner limit position of the valve and may be represented by a line parallel to the sewn short side and passing the edge of the valve on the long side. The distance between the short side where the valve is arranged and the lower limit of the valve represents the height of the valve and the part of the bag that has to be manipulated to open the valve. Furthermore, the term "sewn" valve bag refers to a bag of thin plastic material (thus having little rigidity) and is typically made by hand or low level mechanization (thus having a large dimensional tolerance of-5% or more).

The present invention provides a bag firing system for a firing bag applicator assembly of a rotating wrapper assembly. As is known, the shoot bag applicator assembly includes:

-a feeding device comprising a support plane defining a seat configured for receiving a bag; the feeding device is fed with individual bags or stacks of bags (in this latter case, the feeding device is also provided with unstacking means);

a bag firing system configured for bags to be supplied out of the support plane and for firing the bags to the rotating wrapper (as is known, the firing system comprises valve opening means);

-a bag applicator device configured for cyclic movement between a pick-up position for picking up bags from the support plane of the feeding device and a release position for releasing bags to the bag firing system.

With reference to the bag firing system, the bag firing system is configured for being supplied with bags having valves in a closed configuration and for firing bags having valves in an open configuration to a filling nozzle of a rotating wrapper. As is known, the bag shooting system therefore comprises:

-receiving means configured for receiving a bag from said bag feeding means;

-a firing device configured for being supplied with the pouches by the receiving device and for firing the pouches to the filling nozzles of the rotating wrapper;

-opening valve means acting on the valve before the bag is moved away from the firing means.

During rotation of the wrapper, the shooting-type bag applicator must allow empty or filled bags that have been on the nozzle to pass through the application area. This means that the distance between the bag applicator and the nozzle base must be greater than the short side of the bag.

Starting from the known construction described above, in which according to the prior art no element acts on the bag in the space between the bag applicator and the nozzle base after firing, according to a main aspect of the invention the bag firing system further comprises a guide means extending from the firing means towards the rotating wrapper and configured for acting on the bag during exit of the bag from the firing means. In particular, the newly added means is configured for directing the bag towards the rotating wrapper so as to overcome the problem of trajectory deviation and for maintaining the valve in an open configuration, thereby solving the problem associated with the valve tending to be closed.

The guide means may be mounted substantially close to the rotating wrapper nozzle to improve its effect, and is preferably mounted on a moving support so that it can be switched from a working position to an idle position allowing the bags to pass through without interference.

In order that an unfilled pouch may be advanced through the pouch applicator without any mechanical contact, the guide must be moved (opened) as the filled or unfilled pouch is advanced at the pouch applicator during its rotational movement on the wrapper nozzle.

Preferably, the guiding means are configured for acting on the short side of the bag provided with the valve and/or on the valve inner limit positions (see definition above).

The mechanical shape of the guiding means may be of any kind. In the following description of the figures, embodiments will be described in which the guide means comprise a first pair of left and right guides acting on the short sides of the bag where the valve is arranged and a second pair of guides acting on the lower limit of the valve. These guides, of course, act on two opposite faces of the bag.

Preferably, the bag firing system of the invention can be provided with additional new means which act on the bag as guide means after the bag has left the firing means. In particular, the invention may be provided with a forming device for forcing the valve in the open configuration. The extent of this forcing may counteract the natural tendency of a sewn bag to tend to close the valve prior to firing. The forming means act between the short sides (11) of the bag (7) in an intermediate position corresponding to the inner limit position of the valve (12) and/or between the short sides (11) of the bag where the valve is arranged and the intermediate position.

The invention structurally described above may alternatively be functionally described as a method of operating a bag firing system for a bag firing applicator assembly for feeding sewn valve bags to a rotating wrapper. Thus, the method comprises the steps of:

-feeding the bag with the valve in the closed configuration to a bag firing system as previously described;

-opening the valve;

-firing the bag with the valve in an open configuration towards the filling nozzle of the rotating wrapper.

According to a main aspect of the invention, the innovative method further comprises an action to be performed in the shooting step; in particular the following steps:

-directing the bag towards a nozzle;

-maintaining the valve in the open configuration.

As previously mentioned, the step of directing the bag towards the nozzle has the effect of avoiding trajectory deviation, and the step of maintaining the valve in the open configuration has the effect of limiting the tendency to tend to close the valve.

Preferably, the method may further comprise the step of forcing the valve in an open configuration during the firing step. As previously mentioned, this forcing step has the effect of balancing the natural tendency of the sewn bag to close the valve prior to firing.

Finally, the present invention is also directed to a bag shot applicator assembly for feeding sewn valve bags to a rotating wrapper, wherein the bag shot applicator assembly includes a firing system as previously described. As is known, upstream of the firing system, the bag firing applicator assembly may include:

-a feeding device provided with a support plane configured for receiving the bags; and

-an applicator device configured for cyclic movement between a pick-up position for picking up the pouches from the support plane and a release position for releasing the pouches at the firing device.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and are intended to provide further explanation of the invention as claimed. Other advantages and features of the present invention will become apparent from the following description, the accompanying drawings, and the claims.

The features of the present invention which are believed to be novel are set forth with particularity in the appended claims.

In this context, many terms are used in a manner common to those skilled in the art. Some of these terms are detailed below:

the departure is preferably used to mean/indicate the movement of the bag from one position to another.

Drawings

Other advantageous benefits and advantages of the present invention will become apparent upon a careful reading of the detailed description with appropriate reference to the accompanying drawings.

The invention itself, however, will be best understood by reference to the following detailed description of the invention when read in conjunction with the accompanying drawings, wherein:

FIG. 1 is a schematic view of a rotating wrapper assembly, including a bag firing applicator assembly and a rotating wrapper;

figure 2 is a schematic view of a valve bag;

figures 3 and 4 are schematic views of the valve bag of figure 2 with the relevant closed and open valves, respectively;

figure 5 is a schematic view of a bag shooting applicator assembly;

figure 6 is an enlarged view of the detail of figure 5, marked with the reference VI;

figure 7a is a schematic view of an embodiment of the bag shooting device according to the present invention, with the protruding guide in the working position (closed configuration).

Figure 7b is a schematic view of an embodiment of the bag firing device according to figure 7a, but with the guide in the open position (open configuration, bag passing position) to pass the bag during its rotation on the nozzle opening.

Figure 8a is a schematic view of the interference between the shooting bag on the nozzle and the guide.

Figure 8b is a schematic view of the shooting bag and the guide on the nozzle, schematically showing the avoidance of interference between the bag and the guide in the open position.

Detailed Description

Technical contents and detailed description of the present invention will be described below according to preferred embodiments with reference to the accompanying drawings, which are not intended to limit the scope of the present invention. Any equivalent variations and modifications made in accordance with the appended claims are covered by the claims of the present invention.

Reference will now be made in detail to the accompanying drawings that represent embodiments of the invention. In particular, reference is now made to figure 1, which is a schematic illustration of a rotary wrapper assembly, indicated by reference numeral 1. According to this example, the rotating wrapper assembly 1 of fig. 1 comprises a bag applicator assembly in the form of a bag firing applicator assembly 2, a rotating wrapper 3 comprising a plurality of filling stations 4, and a conveyor 5. As is well known, the shoot bag applicator assembly 2 is configured for being supplied with a valve bag, specifically a stack of multiple valve bags, and shooting the bag onto a nozzle of a filling station. The filling stations 3 are accommodated adjacent to each other in the circumferential direction in a rotating structure 6. Due to the rotation of the rotating structure 6 (indicated by arrow R in fig. 1), each filling station 4 cyclically faces the shot bag applicator assembly 2 to receive an empty bag. Once received, the bags are gradually filled during rotation until reaching the conveyor means 5 where the filled bags are conveyed.

Referring now to fig. 2-4, fig. 2-4 are schematic views of the valve bag of the present invention. As is known, this valve bag 7 is a bag in the form of a rectangular tube having a front face 8 and a rear face 9, and in which each face is defined by two opposite long sides 10, two opposite short sides 11 (defining two opposite ends closed by sewing). The valves 12 are arranged in the form of folded edge portions of the bag itself in the corners between the long sides 10 and the short sides 11. By unfolding the bag 7, the valve 12 can be moved between a closed configuration (see fig. 3) and an open configuration (see fig. 4) in which the folded portions of the opposite faces are separated to form an opening connecting the inner space of the bag itself. It is important to define another line or direction of construction for these sewn valve bags. This line may be defined as the lower or inner limit of the valve 12, which is indicated in fig. 2 by the dashed line 19, the dashed line 19 being a line parallel to the short side 11 and passing the edge of the valve 12 in the long side 10. The distance between the short side 11 provided with the valve 12 and the lower valve limit 19 represents the height of the valve 12 and the part of the bag 7 that has to be manipulated to open the valve 12. According to the invention, the bag 7 can be a "sewn valve bag", i.e. a bag of thin plastic material (therefore hardly rigid) and usually made by hand or low-level mechanisation (therefore with large dimensional tolerances-5% or higher). Also, when storing the bags in a compressed stack, they may be highly misaligned and may be provided with undesirable curvatures. Hereinafter, the term "bag" will refer to a valve bag as described above, in particular also to a sewn valve bag as described above.

Reference is now made to fig. 5 and 6, which schematically disclose the shoot pack applicator assembly 2. In fig. 5, the filling nozzle 13 is also schematically shown facing the shoot bag applicator assembly 2. As is known, the shoot bag applicator assembly 2 includes a feeder 25 provided with a support plane 14 configured for receiving the bag 7. The bags 7 may be supplied to the support plane 14 by an upstream feed plane 26, the upstream feed plane 26 being provided with a feed strip supply, for example with individual bags or stacks of bags. The feeding device 25 may also be provided with a de-stacking device in case a stack of bags is present. Furthermore, the gunbag applicator assembly 2 of fig. 5 comprises an applicator device in the form of an L-shaped swivel arm 15 and is provided with a gripping element 16 at its free end. As is known, this applicator arm 15 is configured to move cyclically between a pick-up position, in which the gripping element 16 is actuated to grip the bag 7 on the support plane 14, and a release position, in which the bag 7 is released by the arm 15 to the shooting device assembly, indicated with reference number 17 in fig. 5. As is known, the shooting assembly 17 is configured for shooting the bag 7 on the nozzle 13, and it also comprises opening valve means in the form of suction elements 18 acting on opposite faces of the bag which remain in a vertical configuration. According to the embodiment disclosed in fig. 5 (as is known), the firing means 17 comprises receiving means in the form of a first belt means 27 configured for receiving the bag from the applicator arm 15 and moving the bag to a firing means in the form of a second belt means 28 configured for firing the bag to the filling nozzle 13. As disclosed, a suction element 18 configured for opening the valve 12 is arranged substantially at the free end of the second band means 28. As is known, a portion of the first strap arrangement 27 is movable between a configuration for receiving the bag 7 and a configuration for moving the bag 7. Along a part of the second band device 28 the firing system 17 is provided with a guide 20 in the form of a vertical parallel wall configured for receiving and guiding the short side 11 of the bag 7 provided with the valve 12. As disclosed in fig. 6, which is an enlarged view of the portion marked with the reference VI in fig. 5, the guide 20 ends with a front plate 21 having a door 22 shaped to allow the passage of the valve in an open configuration. In fact, in this example, the suction device 18 configured for opening the valve 12 is arranged directly upstream of the front plate 21. As is clear from fig. 5, there is no means downstream of the front plate 22 to act on the pocket 7 during firing.

Reference is now made to fig. 7a, which is a schematic illustration of an embodiment of a bag firing system 17 according to the present invention. Proceeding from the structure of the pouch firing system 17 shown in fig. 5, the pouch firing system 17 comprises according to the invention guiding means in the form of a first or upper guide 23 and a second or lower guide 24 extending from the front plate 21 towards the rotating wrapper 3. Thus, after the pouch has exited from the second belt 28 (i.e., the firing means), there is also a means to act on the pouch and the means is configured to properly direct the pouch toward the rotating wrapper. The first or upper guide 23 may represent an extension of the guide 20 acting on the short side 11 of the bag before firing, while the second or lower guide 24 is realized in the form of two rods acting on opposite sides of the bag 7 at the lower valve limit 19. This arrangement of the guides 23, 24 not only allows guiding the bag 7 towards the nozzle, but also keeps the valve 12 in an open configuration during firing. Preferably, the disclosed length of the guides 23, 24 is substantially equal to half the short side 11 of the bag. In particular, the length of the guides 23, 24 may be such that when the front of the valve 12 is in contact with the nozzle 13, the guides 23, 24 still act on the rear of the bag. According to the embodiment of fig. 6, the assembly 17 also comprises several (a pair of) fins 25, which act as forming means against the valve 12. As disclosed, these fins 25 are connected spaced apart to the upper guide 23 and are provided with a rounded edge 26 configured for striking an intermediate portion of the valve 12 after firing, wherein the striking forces the valve 12 to remain in an open configuration after firing.

Although the invention has been described in conjunction with the preferred embodiments described above, it will be understood that many other possible modifications and variations may be made without departing from the scope of the invention. It is, therefore, contemplated that the appended claims will cover such modifications and variations as fall within the true scope of the invention.

Fig. 7b shows a similar embodiment as disclosed in fig. 7a, but in fig. 7b the guide is in an open position.

Fig. 8a shows the interference between the shot bag on the nozzle and the guide. The present invention will eliminate this interference.

Fig. 8b is a schematic view of the firing pouch and guide on the nozzle, showing that interference between the pouch and guide is avoided in the open position.

Claims

1. A bag firing system (17) for a bag firing applicator assembly (2) for feeding a sewn valve bag (7) to a rotating wrapper (3); the sewn valve bag (7) comprising a valve (12), the valve (12) being selectively movable between a closed configuration and an open configuration; a bag firing system (17) configured for being supplied with bags (7) having the valves (12) in a closed configuration and for firing bags (7) having the valves (12) in an open configuration to a filling nozzle (13) of the rotating wrapper (3); the bag firing system (17) comprises:

-receiving means (27) configured for receiving a bag (7);

-a firing device (17) configured for being supplied with the pouches (7) by the receiving device (27) and for firing the pouches (7) to the filling nozzles (13) of the rotating wrapper (3);

-opening valve means (18) acting on the valve (12) before the bag (7) is detached from the firing means (17);

the bag shooting system (17) further comprises:

-guiding means (23, 24, 25) extending from the firing means (17) towards the rotating wrapper (3) and acting on the bag (7) after the bag (7) has exited from the firing means (17), the guiding means being configured for guiding the bag (7) towards the rotating wrapper (3) and for keeping the valve (12) in an open configuration.

2. The bag firing system as claimed in claim 1, wherein the guide means is mounted substantially close to the rotating wrapper nozzle to improve its effect and is mounted on a moving support such that it can be switched from an operative position to an idle position allowing an undisturbed passage of bags.

3. The bag firing system according to claim 1 or 2, wherein the bag (7) comprises two opposite long sides (10), two opposite short sides (11); the valves (12) are located at the corners between the long and short sides; the guide means are configured to act on the short sides (11) of the bag (7) on which the valve (12) is provided and/or on an intermediate position of the bag (7) between the short sides (11) near the inner limit position of the valve (12).

4. A bag firing system according to claim 3, wherein the guiding means comprises a first left and right pair of guides (23) extending from the firing means (17) towards the rotating wrapper (3) and acting on the short side (11) of the bag (7) where the valve (12) is located.

5. A pouch firing system as claimed in claim 3 or 4, wherein the guiding means comprises a second pair of guides (24) extending from the firing means (17) towards the rotating wrapper (3) and acting on the intermediate position of the pouch (7).

6. The bag firing system according to claim 5, wherein the first and second guides have the same length from the firing means (17) towards the rotating wrapper (3).

7. The bag firing system according to claim 6, wherein the length of the first and second guides is substantially equal to half of the short side (11) of the bag (7) where no valve (12) is provided.

8. The bag firing system according to any one of the preceding claims, wherein the bag firing system further comprises a forming device (25) acting on the bag (7) after the bag (7) has exited from the firing device (17) and configured for bringing the valve into the open configuration.

9. The bag firing system according to claim 8, wherein the shaping means (25) act on the short sides (11) of the bag (7) on which the valve (12) is arranged and/or on intermediate positions between the short sides (11) of the bag (7) corresponding to the inner limit positions of the valve (12).

10. A method of operating a bag firing system (17) for a bag firing applicator assembly (2), the bag firing applicator assembly (2) for feeding a sewn valve bag (7) to a rotating wrapper (3); the method comprises the following steps:

a) -providing a bag firing system (17) according to any one of the preceding claims;

b) feeding a bag having a valve in a closed configuration;

c) opening the valve;

d) firing the bag with the valve in an open configuration toward the nozzle;

characterized in that, after the firing step, the method further comprises the steps of:

e) directing the bag toward a nozzle;

f) maintaining the valve in an open configuration.

11. A bag shot applicator assembly (2) for feeding a sewn valve bag (7) to a rotating wrapper (3), the bag shot applicator assembly (2) comprising:

-a feeding device (25) provided with a support plane (14) configured for receiving the bags (7);

-a firing device (17) configured for being supplied with pouches (7) from the support plane (14) and for feeding the pouches (7) to the rotating wrapper (3);

-an applicator device (15) configured for cyclic movement between a pick-up position for picking up the pouches (7) from the support plane (14) and a release position for releasing the pouches (7) at the firing device (17);

it is characterized in that the preparation method is characterized in that,

the firing device is according to any of the preceding claims 1 to 9.