Material handling equipment

Abstract

To provide an article conveying device capable of always holding an article in a stable posture even when the interval between a pair of grip pieces increases.SOLUTION: An article transfer device of the present invention consists of the following. A rail is provided with a stator. A first mover 24 moves along the rail by linear drive through interaction with the stator. A second mover 25 is provided adjacent to the first mover 24 and is driven linearly by interaction with the stator, moving along the rail in synchronization with the first mover 24. Grip pieces 32 and 33 have holding surfaces 34 and 35 for gripping container B. The holding surface 34 of one grip piece 32 is a positioning section that positions the container B. The holding surface 35 of the other grip piece 33 is composed of a belt 36 that can be pressed by the container B and deformed.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to an article conveying device that is driven by a linear motor and travels along a rail, and holds and conveys an article by a pair of grip pieces.

Background Art

[0002] Conventionally, an article conveying device using a linear motor is known. In such an article conveying device, when the conveying path has a straight section and a curved section, a cycloid curve may be adopted for the path of the curved section. However, it is difficult to convey the curved section while maintaining a constant distance between a pair of grip pieces, and the interval between the grip pieces may become wider during conveyance. Also, in the straight section, in the case of a device that conveys an article while sliding it on a plate, it is difficult to always maintain a constant interval between a pair of grip pieces due to the influence of frictional resistance acting on the article.

[0003] On the other hand, in the article conveying device disclosed in Patent Document 1, a recess is formed on the side surface of the conveyed object, and the grip piece is provided with a pressing portion that is in surface contact with the side surface of the conveyed object and a claw portion that can engage with the recess. In the curved section, the conveyed object is held by the claw portion engaging with the recess. According to such a configuration, it is possible to hold the conveyed object even if the interval between a pair of grip pieces slightly widens.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, the article conveying device described in Patent Document 1 conveys articles by placing them in an object to be conveyed, and does not have a configuration that directly grips the articles with grip pieces. In contrast, for example, a filling system for filling containers with liquid is equipped with a conveying device that directly grips the container with grip pieces. For example, when passing through a curved section between the filling process and the capping process, if the grip pieces separate from the container, the container's posture becomes unstable, and there is a risk that the contents of the container will spill from the opening.

[0006] This invention has been made in view of the above-mentioned problems, and aims to provide an article conveying device that can always grip an article in a stable position even when the distance between a pair of grip pieces is large. [Means for solving the problem]

[0007] The article conveying device according to the present invention comprises a rail extending along a conveying path and provided with a stator, a first movable element linearly driven by interaction with the stator and capable of moving along the rail, and a second movable element provided adjacent to the first movable element and linearly driven by interaction with the stator and capable of moving along the rail in synchronization with the first movable element. The first and second movable elements each have a grip piece with a holding surface formed for gripping an article, the holding surface of one grip piece being a positioning part for positioning the article, and the holding surface of the other grip piece being made of a member that can be deformed by being pressed by the article, and gripping the article with the holding surface of the other grip piece deformed. An article conveying device wherein a processing device that performs predetermined processing on an article is arranged along the conveying path, and after the article stops at the processing device, the distance between the pair of grip pieces is widened while the holding surface of the other grip piece is deformed. It is characterized by the following. [Effects of the Invention]

[0009] According to the present invention, it is possible to obtain an article conveying device that can always grip an article in a stable position even when the distance between a pair of grip pieces is large. [Brief explanation of the drawing]

[0010] [Figure 1]This is a schematic plan view showing the configuration of a filling system equipped with an article conveying device, which is a first embodiment of the present invention. [Figure 2] This is a plan view showing the state of a pair of grip pieces during transport and when stopped. [Figure 3] This is a side view showing the article transport device of the first embodiment, stopped at the capper. [Figure 4] This is a plan view showing the grip piece of the second embodiment. [Figure 5] This is a plan view showing the grip piece of the third embodiment. [Figure 6] This is a plan view showing the grip piece of the fourth embodiment. [Figure 7] This is a plan view showing the grip piece of the fifth embodiment. [Modes for carrying out the invention]

[0011] The present invention will be described below in accordance with the illustrated embodiments. Figure 1 is a schematic plan view showing the configuration of a filling system equipped with an article conveying device, which is a first embodiment of the present invention. The article conveying device is provided between a supply conveyor 11 and a discharge conveyor 12 and has a plate 13 which is an endless conveying path. In this embodiment, the conveying path consists of two relatively long straight sections P1, two relatively short straight sections P2, and four curved sections Q connecting them. An empty container (article) B is conveyed by the supply conveyor 11 and transferred onto the plate 13 by the supply device 14. The container B is conveyed counterclockwise in the figure as it slides on the plate 13, filled with liquid by the filler 15, a cap is attached to the opening by the capper 16, and transferred to the discharge conveyor 12 by the discharge device 17 for discharge to the next process.

[0012] Rails 21 and 22 are arranged vertically (see Figure 3) and extend endlessly along the inside of plate 13. Between rails 21 and 22, electromagnetic coil units 23 (see Figure 3), which are stators consisting of electromagnetic coils arranged at predetermined intervals inside, are provided at predetermined intervals along the transport path. A pair of movable elements 24 and 25, which are linearly driven by interaction with the stators, are movably supported on rails 21 and 22. The pair of movable elements 24 and 25 are adjacent to each other, and for convenience in this specification, the one located upstream is referred to as the first movable element 24, and the one located downstream is referred to as the second movable element 25.

[0013] The first and second movable elements 24 and 25 have permanent magnets 31 (see Figure 3) positioned opposite the electromagnetic coil unit 23 and move synchronously along the rails 21 and 22. The movement of these movable elements 24 and 25 is controlled by a control device (CPU) 26, which guides them along the rails 21 and 22 to move at a predetermined speed and to stop at a predetermined position. At the stopping position, the distance between the movable elements 24 and 25 is finely adjusted by the control device 26.

[0014] The first and second movable elements 24 and 25 each have grip pieces 32 and 33, and these pair of grip pieces 32 and 33 have holding surfaces 34 and 35 for gripping container B. That is, container B is supported on its rear side in the transport direction by the grip piece 32 of the first movable element 24, and its front side is supported on its grip piece 33 of the second movable element 25, and its bottom surface is supported on the plate 13, and it is transported along the transport path.

[0015] The configurations of grip pieces 32 and 33 will be explained with reference to Figure 2. Reference numeral (a) indicates the state during transport. Reference numeral (b) indicates the state when stopped, such as during capping, and grip piece 33 is shown with the cover removed to explain its internal structure. One grip piece 32 is molded from a resin material such as ultra-high molecular weight polyethylene, and the holding surface 34 facing the other grip piece 33 has a concave shape corresponding to the outer shape of the container B and acts as a positioning part for positioning the container B. In the other grip piece 33, the holding surface 35 facing the grip piece 32 is made of a member that can be deformed by being pressed by the container B, and in this embodiment this deformable member is a belt 36.

[0016] One end of the belt 36 is directly fixed to the grip piece 33 by a fastener 41, and the other end is fixed to the swing lever 43 by a fastener 44. The swing lever 43 is swingably supported on the grip piece 33 by a rotating shaft 42. Between the fasteners 41 and 44, the belt 36 engages with a pin 45 provided at the tip of the grip piece 33 and the tip portion 43a of the swing lever 43 on the holding surface 35 side. A spring 37 is connected to the base end 43b of the swing lever 43 opposite to the tip portion 43a, and the swing lever 43 is biased by the spring 37 in a direction that moves the tip portion 43a away from the pin 45, thereby applying tension to the belt 36. Furthermore, on the grip piece 33, the back side of the belt 36 has a concave shape corresponding to the outer shape of the container B, similar to the holding surface 34 of the grip piece 32. Therefore, when the container B is gripped by the pair of grip pieces 32 and 33, if the grip pieces 32 and 33 are displaced in the closing direction, the belt 36 can deform in a direction closer to the grip piece 33, against the spring force of the spring 37.

[0017] Figure 3 shows the article conveying device stopped in the capper 16. The second mover 25 has an upper roller 25a engaged with a groove formed in the upper rail 21 and a lower roller 25b abutting against the side surface of the lower rail 22. A permanent magnet 31 is provided at a height position corresponding to the electromagnetic coil unit 23 between the upper roller 25a and the lower roller 25b. In the capper 16, the container B is conveyed directly below the capping head 16a and is gripped by the centering grippers 16c, 16c of the pair of cylinder devices 16b, 16b. Although not shown, the centering grippers 16c, 16c are formed with V-shaped positioning portions in a plan view on the gripping surfaces for gripping the container B, and are configured to position the container B by gripping it with the positioning portions. With the container B positioned by the centering grippers 16c, 16c, the capping head 16a descends and the cap C is attached to the mouth of the container B.

[0018] Next, the operation of this embodiment will be described. The container B is conveyed in a standing state by the supply conveyor 11 and supplied to the supply device 14. In the supply device 14, a robot (not shown) grips the container B and transfers it between a pair of grip pieces 32, 33 waiting on the plate 13. The grip pieces 32, 33 narrow the interval therebetween, whereby the belt 36 of the grip piece 33 is deflected, and the container B is pressed and held by the grip pieces 32, 33. The containers B are conveyed in sets of three, and in the filler 15, the three containers B are each positioned directly below a filling nozzle (not shown), and are simultaneously filled with the filling liquid discharged from the filling nozzle.

[0019] The three filled containers B are conveyed to cappers 16 and positioned respectively directly below capping heads 16a. The positioning operation of container B in the capping process will be described with reference to FIG. 2. During conveyance, as shown by reference numeral (a), the distance between the pair of grip pieces 32, 33 is relatively narrow and the belt 36 is deflected relatively greatly. That is, the pressing force received by container B from the grip pieces 32, 33 is relatively large and container B is held relatively firmly. When container B is positioned below capping head 16a, as shown by reference numeral (b), the first mover 24 is moved the same distance upstream in the conveyance direction and the second mover 25 is moved the same distance downstream in the conveyance direction, whereby the distance between the pair of grip pieces 32, 33 is slightly widened. As a result, container B moves together with grip piece 32 while being pressed against the holding surface 34 of grip piece 32 of the first mover 24 by belt 36. In this state, when centering grippers 16c, 16c (FIG. 3) advance to grip container B, since the pressing force of grip pieces 32, 33 against container B has decreased, the position of container B is moved following the positioning portion formed in centering gripper 16c, and the center of the mouth of container B is aligned with the axis of capping head 16a (FIG. 3).

[0020] Even if the distance between grip pieces 32, 33 is widened in this way, the pressing force against container B does not become zero. This is because if the pressing force were to become zero, container B could rotate and displace due to inertia during stoppage, and its posture could be disrupted.

[0021] Also, when container B is conveyed through the curved section Q, even if the distance between the pair of grip pieces 32, 33 becomes wider, since the holding surface 35 of grip piece 33 can be deformed while exerting the pressing force by belt 36, container B can be conveyed while being constantly pressed. Therefore, container B is always conveyed in a stable posture.

[0022] Note that the operation of widening the distance between the pair of grip pieces 32, 33 for conveying container B is also executed when container B is gripped by a robot provided in discharge device 17 at the time of stoppage.

[0023] As described above, according to this embodiment, the holding surface 35 of the grip piece 33 is made of a belt 36 that can be deformed by the pressing force received from the container B, so that even if the distance between the pair of grip pieces 32 and 33 becomes large, the container B can always be gripped in a stable position.

[0024] Figure 4 shows a grip piece 50 of the second embodiment. The grip piece 50 has L-shaped arms 52, each pivotally supported on a pair of rotating shafts 51. The grip piece 50 has a concave surface 53 that corresponds to the shape of the container B to be gripped, and the holding surfaces 54 of each L-shaped arm 52 are deformable between a concave state that matches the concave surface 53 (reference numeral (a)) and a planar state that is aligned in a straight line with each other (reference numeral (b)). That is, the base ends of the pair of L-shaped arms 52 are biased toward each other by a spring 55, and the holding surfaces 54 are in a planar state when no external force is acting on the arms 52, and are displaced when pressed by the container B when gripping the container B.

[0025] Figure 5 shows a grip piece 60 of the third embodiment. The grip piece 60 is provided with a pair of pulleys 61, and an O-ring 62 is wound around each pulley 61. The grip piece 60 has a concave surface 63, similar to the second embodiment, and the holding surface 64 of the O-ring 62 is flat when no external force is applied, but when gripping container B, it is pressed by container B and deforms toward the concave surface 63 side.

[0026] Figure 6 shows the grip piece 70 of the fourth embodiment. The grip piece 70 has a leaf spring 71 that extends along its outer shape, and both ends of the leaf spring 71 are shaped into an arc. A belt 72 is provided on the outer circumference of the leaf spring 71, and both ends of the belt 71 and the leaf spring 71 are fixed to the grip piece 70 by a pin 73. The grip piece 70 has a concave surface 74, similar to the second embodiment, and the holding surface 75 of the belt 72 is flat when no external force is applied, but when gripping container B, it is pressed by container B and deforms toward the concave surface 73 side, bending both ends of the leaf spring 71.

[0027] Figure 7 shows the grip piece 80 of the fifth embodiment. The difference between the grip piece 80 and the fourth embodiment is that the leaf spring 81 is inserted into and fixed in a groove 82 formed in the grip piece 80, and the belt 83 is endless; the other configurations are the same as in the fourth embodiment. That is, the grip piece 80 has a concave surface 84 as in the second embodiment, and the holding surface 85 of the belt 83 is flat when no external force is applied, but when gripping container B, it is pressed by container B and deforms toward the concave surface 84 side, bending both ends of the leaf spring.

[0028] The same effects as those of the first embodiment can be obtained by the second to fifth embodiments. [Explanation of symbols]

[0029] 13 Plates (Transportation Route) Rails 21 and 22 23 Electromagnetic coil unit (stator) 24 First movable element 25 Second movable element 32, 33, 50, 60, 70, 80 grip pieces 35, 54, 64, 75, 85 holding surface 36, 72, 83 Belt (deformable component) 52 L-shaped arm (deformable component) B Container (article)

Claims

[Claim 1] A rail extending along the transport path and equipped with a stator, A first movable element, which is linearly driven by interaction with the stator and is movable along the rail, The system includes a second movable element provided adjacent to the first movable element, which is linearly driven by interaction with the stator and moves along the rail in synchronization with the first movable element, Each of the first and second movable members has a grip piece formed with a holding surface for gripping an article, The holding surface of one of the grip pieces is a positioning part that positions the article, The holding surface of the other grip piece is made of a member that can be deformed by being pressed by the article, An article conveying device that grips the article while deforming the holding surface of the other grip piece, An article conveying device characterized in that a processing device which performs a predetermined process on the article is arranged in the conveying path, and after the article stops at the processing device, the distance between the pair of grip pieces is widened while the holding surface of the other grip piece is deformed.

Images