Patent Publication Number: US-2012035759-A1

Title: Bag Dispensing Device, Bag Dispensing Machine Comprising Said Device, and Automated Method for Packing Bags

Description:
OBJECT OF THE INVENTION 
     The object of the Invention Patent herein is to register a bag dispensing device, a machine comprising said device that incorporates significant innovations and advantages and an automated method for packing bags. 
     More specifically, the invention relates to a bag dispensing device and a machine that incorporates the aforementioned device, especially for bags of the type that have a previously lined base part that is superimposed in a lateral wall of the bag, enabling the supply of bags in a fast and automated manner. 
     BACKGROUND OF THE INVENTION 
     Nowadays, the use of bags provided by retailers to their customers to carry products purchased is widespread. Among the wide variety of bags known, we must mention those that have a fold near the base such that when the bag is stored it occupies a smaller space as the base part of the bag becomes superimposed in one of the lateral walls, while in a condition of use of the bag, the fold can increase the surface of the base of the bag thereby adapting a substantially rectangular prism shaped interior volume. 
     With respect to the bag packing method described above and prior supply to the point of sale, such bags are manually placed in boxes in a preset number by operators who must conduct a manual count as a bag is taken and placed in the appropriate box. 
     Nonetheless, this process that is carried out manually given the presence of the fold in the bag requires a number of staff thus involving a higher production cost. Another drawback is the fact that the operator may make a mistake at any time during the counting of bags which can cause rejection of the supply of boxes with the bags packed. 
     Another operation that the operator must do before placing the bag in the appropriate box is to check that the lined part of the bag, which has been joined in a previous stage, has been carried out correctly. 
     In view of all the foregoing there is a need for a machine or device free from the drawbacks described above. 
     DESCRIPTION OF THE INVENTION 
     The invention herein has been developed to provide a bag dispensing device that resolves the aforementioned drawbacks, further providing other additional advantages that will be apparent from the description detailed hereinafter. 
     It is therefore a first object of the invention to provide a bag dispensing device in which the bag is of the type that has a previously lined base that is superimposed in a lateral wall of the bag, characterized in that it comprises: a bag supply conveyor belt provided with control means using artificial vision that capture the geometric shapes of the lined base part of the bag and compare them with predefined measurements; counting means connected to the control means such that each bag that passes through the belt is counted and a sorting element linked to the control means using artificial vision and to the counting means, such that the dimensionally correct bags are piled vertically one on top of the other in a pile with a preset number of bags, while in the event that the bag may be dimensionally incorrect, it is sent to a second location. 
     In this descriptive memory the term “dimensional” shall be understood as geometric shapes and not necessarily dimensions per se. Preferably, the sorting element comprises two rotating elements parallel and separated from each other that define a horizontal support surface, an ejection channel. Each rotating element is actuated by an electric actuator coupled to a actuation shaft, such that it transmits the rotary movement from the actuator shaft to the rotating element. These two rotating elements spin simultaneously in operating conditions. In one embodiment of the invention, the control means using artificial vision comprise image capture cameras connected to a server provided with arbitrary means that ensure quality control and inspection and high reliability. Such means work by taking pictures of the bags. 
     Advantageously, the device of the invention further comprises means for moving the pile of bags from the piling station synchronized with the counting means, such that when the pile has the preset number of bags, such movement means move the pile situated near the sorting element. 
     Thanks to these characteristics, a work process can be automated, which until now has been manual, and which ensures a predefined number of bags to be supplied in work cycles without manual counting and as a result ruling out an error in the manual counting of bags and ensuring visual inspection of 100% of the bags. In addition, production costs can be reduced as the number of operators required thus far is reduced and, in turn, the level of productivity is increased. 
     It is another object of the invention herein to provide a new bag dispensing machine in which the bag supplied has a previously lined base part that is superimposed in a lateral wall of the bag, which comprises at least one bag dispensing device of the type described hereinabove. According to another aspect of the machine of the invention it comprises a conveyor belt in which pressing means for boxes are arranged, installed on the previously mentioned robot arm. Such pressing means may comprise a cylinder-piston system, whose piston is vertically movable by actuation means, said piston being provided at its free end with at least one plate that comes into contact with the upper part of the boxes. 
     Thus, by using a relatively simple construction system the air that could be inside each one of the bags is eliminated, allowing more storage inside each box since the height of the boxes could be reduced by 20% and thus represents a considerable saving in the material the boxes are made from, as well as savings in transportation costs. The presence of air was due to the operator concerned limiting the pressing force on the bags. 
     Additionally, the machine is provided with guiding means for linear positioning of the boxes in respect of the pressing means that ensure the proper functioning of the bag packing operation. 
     Lastly, it is also an object of the invention herein to provide an automated method for packing bags, in which the bag is of the type that has a previously lined base part that is superimposed in a lateral wall of the bag, characterized in that it comprises the following stages:
         capturing the geometric shapes and presence of the lined base part of a bag arranged on a horizontal plane; and   comparing the geometric shapes of said bag with preset geometric shapes on a central server;       

     such that in the case of the compared geometric shapes being acceptable, the bag is piled in a vertical pile for subsequent packing operations while if the bag is not accepted, it is sent to a second rejection location. Other characteristics and advantages of the device object of the invention herein will become apparent from the description of a preferred, although not exclusive embodiment, which is illustrated by way of non-limiting example in the drawings appended, in which: 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG.  1 .—Perspective view of a bag dispensing device according to the invention herein in which various components have been omitted for the purposes of clarity; 
       FIG.  2 .—Top plan view of the sorting element that is part of the mechanism shown in the figure above; 
       FIGS.  3 A and  3 B.—Two perspective views of a bag dispensing machine according to the invention herein; 
       FIG.  4 .—Detailed front elevation view of the additional means for pressing and closing boxes supplied in the dispensing machine; 
       FIG.  5 .—Detailed front elevation view of the closing station; 
       FIG.  6 .—Side elevation view of the machine according to the invention in which some parts have been omitted to facilitate comprehension; 
       FIG.  7 A.—Perspective view of one embodiment of the type of bag handled by the device and machine of the invention herein; and 
       FIG.  7 B.—Plan view of the bag above in a closed condition. 
     
    
    
     DESCRIPTION OF A PREFERRED EMBODIMENT 
     In view of the attached figures, an embodiment of a bag dispensing machine of a certain type comprising a bag dispenser device indicated generally by reference  1  and detailed below is shown. In particular, the bags  30  supplied are those with a previously lined base part  31  that is superimposed in a lateral wall  32  of the bag  30  and a pair of grip handles  33  (see  FIGS. 7A and 7B ). This type of bag  30  is widely used by businesses, especially those dedicated to retail sale in the textile industry, etc. 
     With particular reference to the dispensing device  1 , this essentially comprises a conveyor belt  2  for the supply of bags supported by a structure  16  that includes control means by using artificial vision, such as three high-resolution cameras (not shown) that capture the geometric shapes of the lined base part of the bag and compare them with predefined measurements. Simultaneously, the presence or absence of the grip handle provided in the bag with said control means is also checked. The cameras are not explained in greater detail herein since the elements are commercially available. Means (not shown) are also provided in the area of the conveyor belt  2  that verify the presence of the bag handles  30 , which are connected to the control means of the dispensing device  1 . Although it is not shown in this embodiment, the conveyor belt  2  can have an additional belt located superiorly that acts as a guiding element for the bags that are fed, such that the bags do not move in the wrong direction prior to verification. 
     Additionally, there are also counting means connected to the control means such that each bag  30  which passes through the belt is counted and a sorting element, referenced generally by  3 , linked to the control means by artificial vision and the counting means, such that the dimensionally correct bags are piled  30  vertically one above the other in a pile with a preset number of bags arranged in a bucket  26  or any other element that is suitable to receive the bags, while in the event that the bag  30  may be dimensionally incorrect, it is sent to a second location that corresponds to a container for defective parts. 
     With reference to the sorting element  3  it comprises two rotating elements  4 ,  5  arranged in parallel which have a horizontal support surface and an ejection channel through which the rejected the bag is sent, said channel being defined by two beams  6  and  7 . Both rotating elements  4  and  5  are each formed by four arms  4 A,  4 B,  4 C,  4 D, and  5 A,  5 B,  5 C and  5 D, respectively, in a cross-shaped arrangement that can be adjusted electrically in position to adapt to the width of the bag to be handled. These rotating elements  4  and  5  are independently controlled by two electric actuators  8 ,  9  that act on two separate actuation shafts  10 ,  11  connected to each of the rotating elements  4 ,  5 . 
     As can be seen, the various components that comprise the sorting element  3  are supported on a metal frame comprising a plurality of plate-shaped metal profiles joined together. Also, the device comprises means for moving the pile of bags from the piling station synchronized with the counting means, such that when the pile has the preset number of bags, said movement means move the pile situated near the sorting element  3 . These movement means consist of a robot arm  13  axially movable on three linear coordinate axes  5  (X, Y, Z) and an axis of rotation (that rotates on its vertical axis) that includes a grip or clamping element of the pneumatic type,  27  (see  FIG. 6 ) on its end, carrying out the movement of said robot arm  13  by means of actuators. The robot arm moves on the X and Y axis by means of two conventional pads  23  and  24  arranged transversely to each other. 
     Additionally, the dispensing machine comprises a conveyor belt  14  which is located parallel to the abovementioned dispensing device  1 , provided with additional pressing means for boxes  20 . In the event the conveyor belt  14  runs out of boxes  20  a light and sound signal indicates the lack thereof, and a minimum of three minutes is given from the time the signal is emitted for the boxes  20  to be replenished on said conveyor belt  14 . 
     As can be seen more clearly in  FIG. 4 , these additional pressing means are composed of a cylinder-piston system secured to a support structure  15 , whose piston  16  is moved vertically, with said piston  16  provided at its lower free end with a plate  17  that comes into contact with the upper part of the boxes and, more specifically, with the pile of bags  30  housed inside the box  20  such that they can be compacted. 
     There is a closing station, indicated generally by reference  25 , which enables the upper flaps  5  of the handled box  20  to be closed, leaving it ready for shipment. The support structure  15  has two lateral guides  18 ,  19  facing each other which enable the correct positioning of the box to ensure the pressing and closing operations of said box  20 . Each of the guides  18 ,  19  is defined by a plurality of juxtaposed linearly movable rollers  21 . The closing of the boxes  20  is performed by means of a series of plates arranged on both sides of the box, pneumatically actuated and on the upper part of the station structure.  FIG. 4  shows a clear reference to the plate located superiorly with its respective pneumatic cylinder  29 . 
     The machine is controlled by an industrial PC housed in a housing  22  where the operating parameters of the various component parts that make up the machine can be viewed and modified according to job requirements or type of bag to be handled and the number of bags to be placed in each box for supply can also be programmed, for example. 
     The details, shapes, dimensions and other accessory elements as well as the materials used in the manufacture of the machine and devices of the invention may be conveniently replaced by others that are technically equivalent and do not depart from the essential nature of the invention or from the scope defined by the claims included hereinafter.