Material handling equipment

Abstract

To provide an article conveying device which is equipped with a gripper consisting of a pair of grip pieces provided on adjacent movable elements and has a wide range of common use for articles that can be held by the gripper even if the movement range of adjacent movable elements is limited.SOLUTION: Each gripper 3 of the linear conveying device 6 (article conveying device of the present invention) includes a grip piece 3A provided on one adjacent movable elements 16 and a grip piece 3B provided on the other adjacent movable elements 16. When holding the smallest container 2 with the gripper 3, the adjacent movable elements 16 are brought closest to each other, and the pair of grip pieces 3A and 3B are moved horizontally with respect to the movable elements 16 to bring them closer to each other ( (See Figure 3(c)). When holding the largest container 2 with the gripper 3, the adjacent movable elements 16 are separated as much as possible, and the pair of grip pieces 3A and 3B are moved horizontally with respect to the movable elements 16 to maximize the separation. (see Figure 3(d)).SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to an article conveying device, and more particularly to an article conveying device using a linear motor, which holds and conveys an article by grippers provided across a pair of adjacent movers.

Background Art

[0002] Conventionally, a linear conveying device configured to convey an article using a linear motor has been known (see, for example, Patent Document 1 and Patent Document 2). In such a conventional linear conveying device, one grip piece is attached to one mover, and the article is conveyed while being held at the front and rear by a gripper (holding means) composed of a pair of adjacent grip pieces.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, in the above conventional linear conveying device, when attempting to hold articles having different dimensions in the conveying direction, the interval between adjacent movers is adjusted to change the interval between a pair of adjacent grip pieces to match the dimension of the article. Specifically, when holding an article having a small dimension in the conveying direction with the gripper, the interval between a pair of adjacent grip pieces, that is, the interval between adjacent movers, is set narrow, and when holding an article having a large dimension in the conveying direction with the gripper, it is necessary to set the interval between a pair of adjacent grip pieces, that is, the interval between the movers, wide. Incidentally, since the gripping piece is attached to the movable part, when holding a small item with the gripper, the limit was the position where adjacent movable parts did not interfere with each other. Furthermore, for example, if the item is a container and the container is held by multiple grippers, each consisting of a pair of grip pieces, and then transported to a filling device for filling with liquid, the pitch of adjacent containers must match the pitch of adjacent filling nozzles in the filling device. Therefore, when holding a large container with a gripper, the limit was the position where it would not interfere with the movable part of the gripper holding the adjacent container. In this case, increasing the range of motion of the movable part would also increase the pitch of the filling nozzles, resulting in a larger filling device itself, higher manufacturing costs, and thus undesirable. Therefore, the object of the present invention is to provide an article conveying device equipped with a gripper that can broaden the range of articles that can be held, even if there is a limitation on the range of movement of adjacent movable elements for moving a pair of grip pieces that constitute the gripper. [Means for solving the problem]

[0005] In view of the circumstances described above, the present invention comprises a plurality of movable elements, a stator for linearly driving the movable elements along a predetermined transport path, and a grip piece provided on one of two adjacent movable elements, and a grip piece provided on the other movable element. In an article conveying device in which a gripper is formed by the gripping pieces of the two movable elements described above to hold an article, and the two movable elements are moved synchronously to convey the article held by the gripper along the conveying path described above, The above-mentioned gripper is configured such that each of the grip pieces is movably mounted relative to the movable element on which the grip piece is attached in the direction of transporting the article, Each grip piece in the movable element provided with each of the above grip pieces A positioning mechanism is provided to position the transport direction. Furthermore, a switching mechanism is provided that operates the positioning mechanism to switch the position of the grip piece in the movable element. Depending on the width in the conveying direction of the article held by the gripper, The above switching mechanism activates the above positioning mechanism, One grip piece and the other grip piece upThis invention is characterized by positioning the movable element either upstream or downstream in the transport direction. [Effects of the Invention]

[0006] This configuration allows for a wider range of items that can be held by the gripper, thus suppressing increases in manufacturing costs and providing a highly versatile item handling device. [Brief explanation of the drawing]

[0007] [Figure 1] A plan view showing one embodiment of the present invention. [Figure 2] Figure 2(a) is a front view of the main part of Figure 1, Figure 2(b) is a longitudinal section of the main part of Figure 1, and Figure 2(c) is a cross-sectional view of the main part along the line II-II in Figure 2(a). [Figure 3] Figures 2(a) to 2(c) are plan views showing how the grippers hold containers of different sizes. [Figure 4] Figure 4(a) is an explanatory diagram showing the state in a conventional device where adjacent movable elements are brought as close together as possible to minimize the gap between grippers, and Figure 4(b) is an explanatory diagram showing the state in a conventional device where adjacent movable elements are separated as far apart as possible to maximize the gap between grippers. [Figure 5] Figure 5(a) is an explanatory diagram showing the state in this embodiment where adjacent movable elements are brought as close together as possible to minimize the gap between the grippers, and Figure 5(b) is an explanatory diagram showing the state in this embodiment where adjacent movable elements are separated as far apart as possible to maximize the gap between the grippers. [Figure 6] Figure 6(a) is a perspective view showing a second embodiment of the gripper and the like of the present invention, where Figure 6(a) shows a state in which a small-diameter container is held by the gripper, and Figure 6(b) shows a case in which a large-diameter container is held by the gripper. [Figure 7] Figure 6 shows a front view and a top view illustrating how the gripper holds containers of different sizes. Figures 7(a) and 7(c) show the gripper holding a large container, while Figures 7(b) and 7(d) show the gripper holding a small container. [Figure 8]Figures 6 and 7 show side views illustrating the engagement relationship between the gripper's grip piece and the cam. [Modes for carrying out the invention]

[0008] The present invention will now be described with reference to the illustrated embodiments. In Figures 1 and 2, 1 is a filling system for filling a container 2 with liquid. This filling system 1 has a number of grippers 3 that hold the container 2 which are circulated along a circulating transport path R in the direction of the arrow. After the container 2 is supplied to the grippers 3 stopped at supply position A by a supply robot 4 and held, the container 2 held by the grippers 3 is transported to filling position B and stopped, where a predetermined amount of liquid is filled into the container 2 by a filling device 5. The filling system 1 includes a linear conveying device 6 as an article conveying device that holds and conveys containers 2 with a gripper 3, a supply robot 4 positioned at supply position A in the circulating conveying path R of the linear conveying device 6 to supply empty containers 2 to the gripper 3, a filling device 5 positioned at filling position B downstream of supply position A in the circulating conveying path R to fill liquid into containers 2, a capping device 7 provided at capping position C downstream of filling position B in the circulating conveying path R, an inspection device 8 provided at inspection position D downstream thereof to inspect containers 2, a discharge robot 9 provided at discharge position E downstream of inspection position D, and a control device 11 that controls the operation of these components, etc.

[0009] Although not shown in Figure 1, a Ferriplate 12 is positioned to support the bottom of the container 2 from the supply position A to the discharge position E downstream in the transport direction. The container 2, which is held and transported by the gripper 3, is supported by the Ferriplate 12 and slides along its surface. A nut member 13 is connected to the lower part of the Ferriplate 12, and this nut member 13 is screwed onto a ball screw 14 positioned vertically. The ball screw 14 is rotated by a servo motor M1, and the operation of this servo motor M1 is controlled by a control device 11. If the height or shape of the container 2 to be processed is changed, the control device 11 rotates the servo motor M1 by the required amount, thereby changing the height of the Ferriplate 12. This allows the gripper 3 to hold the body of the container 2 at a suitable height. A linear supply conveyor 15 is positioned parallel to the circulating transport path R at supply position A, and empty containers 2 arranged in a vertical line in an upright position are supplied to supply device A by the supply conveyor 15 and stopped there. A supply robot 4 is positioned at supply device A, and the supply robot 4 grasps the empty containers 2 on the supply conveyor 15, widens the spacing between adjacent containers 2, and then has the containers 2 held by eight grippers 3 that are stopped on the ferriplate 12 at supply position A. The gripper 3 consists of a grip piece 3A provided on one adjacent movable element 16 and a grip piece 3B provided on the other adjacent movable element 16. These pair of grip pieces 3A and 3B hold the body of the container 2 from the front and rear in the transport direction (see Figure 3). As described above, the container 2 held by the gripper 3 is supported by the ferriplate 12 and slides on its surface. The container 2, into which the liquid is filled, has a body and an upper opening, and the liquid is filled into the interior from the upper opening.

[0010] The linear conveying device 6, as an article conveying device, comprises a pair of upper and lower rails 17 arranged along an endless circulating conveying path R, an electromagnetic coil unit 18 arranged over the entire circulating conveying path R between these upper and lower rails 17 and having a large number of electromagnetic coils provided inside at predetermined intervals, and a large number of movable elements 16 arranged adjacent to the electromagnetic coil unit 18 and moving along the circulating conveying path R guided by the rails 17. The electromagnetic coil unit 18 constitutes the stator of the linear motor for the movable elements 16. A permanent magnet 19 is embedded in the movable element 16, facing the electromagnetic coil unit 18, and multiple rollers 16A are rotatably provided at vertical positions that roll along the guide surfaces of the upper and lower rails 17. In this embodiment, a gripper 3 that holds the container 2 is formed by a grip piece 3A provided on one adjacent movable element 16 (the movable element 16 on the upstream side in the conveying direction) and a grip piece 3B provided on the other adjacent movable element 16 (the movable element 16 on the downstream side in the conveying direction) (see Figure 3). The numerous electromagnetic coils located within the electromagnetic coil unit 18 are individually energized at the required timing by the control device 11. The control device 11 synchronizes the movement of a pair of adjacent movable elements 16 along the circulating transport path R, thereby moving each gripper 3, consisting of grip pieces 3A and 3B attached to the pair of movable elements 16, along the circulating transport path R, and also allows for individual control of the movement position and speed during the movement. By exciting the electromagnetic coil at the required position along the circulation conveyance path R, the gripper 3 provided across the pair of adjacent rotors 16 can be circulated at a predetermined speed along each position A to E along the circulation travel path R and stopped at the required position. Thereby, the container 2 held by the gripper 3 is conveyed from the supply position A to the discharge position E by the linear conveyance device 6. Further, by adjusting the interval in the conveyance direction of the pair of adjacent rotors 16 by the control device 11, the interval between the pair of grip pieces 3A and the grip piece 3B can be adjusted, whereby containers 2 having different sizes can be held in common by the gripper 3. Note that the basic configuration of the linear conveyance device that moves the rotor by linear drive is conventionally well-known, and thus detailed description thereof is omitted here.

[0011] Here, referring to FIG. 1, the conveyance of the container 2 by the gripper 3 of the linear conveyance device 6 and the outline of the processes performed at each position A to E will be described. When eight grippers 3 are stopped above the ferriplate 12 at the supply position A and the upright empty container 2 is supplied to the supply device A by the supply conveyor 15, the supply robot 4 grips the empty container 2 on the supply conveyor 15 and then widens the interval between adjacent containers 2 and causes the eight grippers 3 stopped at the supply position A to hold the container 2. At this time, as described above, the bottom of the container 2 is supported by the ferriplate 12. When the container 2 is held by the gripper 3 at the supply position A, the six grippers 3 holding the empty container 2 are moved to the filling position B and stopped. The filling device 5 is provided with six filling nozzles (not shown) at equal pitches along the conveyance direction of the container 2, and the containers 2 held by the six grippers 3 and stopped at the filling position B are located below the six filling nozzles. Then, a predetermined amount of liquid is filled into the six containers 2 by the filling nozzles of the filling device 5. After that, the six grippers 3 holding the liquid-filled containers 2 are conveyed to the capping position C and stopped there. A capping device 7 is arranged at the capping position C, and caps are attached to the upper port portions of the six containers 2 by the capping device 7 to be closed. After that, the gripper 3 holding the container 2 with the cap attached is conveyed to the inspection position D and stopped. An inspection device 8 is arranged at the inspection position D, and the inspection device 8 inspects the presence or absence of foreign matter and capping defects for every four containers 2. The containers 2 that have completed the inspection by the inspection device 8 at the inspection position D are then conveyed to the discharge device E and stopped. A discharge robot 9 and a discharge conveyor 21 are arranged at the discharge position E. The discharge robot 9 takes out four containers 2 at a time from the gripper 3 stopped at the discharge position E and delivers them onto the discharge conveyor 21. The containers 2 delivered onto this discharge conveyor 21 are conveyed downstream. On the other hand, the gripper 3 from which the container 2 has been taken out and emptied at the discharge position E is moved to the supply position A and stopped again there. Note that the containers 2 determined to be defective as a result of the inspection by the inspection device 8 are rejected from the discharge conveyor 21 by a reject device (not shown) after being delivered to the discharge conveyor 21. Thus, the filling system 1 of this embodiment sequentially conveys the containers 2 held by the grippers 3 of the linear conveying device 6 along the circulation conveying path R from the supply position A to the discharge position E, and performs filling of liquid into the containers 2, subsequent capping, and required inspections.

[0012] Thus, on the premise of the above configuration, this embodiment makes the pair of grip pieces 3A and 3B constituting the gripper 3 horizontally movable along the conveying direction with respect to the mover 16 on which they are provided, thereby expanding the versatility of the containers 2 that can be held by the gripper 3. The following will describe the configuration of a pair of adjacent movable elements 16 and the grip pieces 3A and 3B of the grippers 3 provided thereon, with reference to Figures 2 and 3. A base member 22 is horizontally connected to the upper part of each movable element 16, and a rotating shaft 23 is fixed to the center of the upper surface of this base member 22 (center in the transport direction) with its orientation facing vertically upward. A support block 24 is positioned above the rotating shaft 23, and a fixed shaft 25 is fixed vertically upward to the center of the upper part of this support block 24. A mounting base 26 is horizontally fixed to the upper end of this fixed shaft 25. A grip piece 3A is horizontally connected to one adjacent mounting base 26, and a grip piece 3B is horizontally connected to the other adjacent mounting base 26. The main body (lower portion) of the support block 24 has a through hole in the vertical direction, and the upper end (free end) of the rotating shaft 23 is rotatably passed through this through hole. In other words, the support block 24 is pivotably mounted on the rotating shaft 23, and the grip piece 3A (3B) is attached via a mounting base 26 fixed to a fixed shaft 25 erected on the support block 24. One end of the connecting shaft 27 is connected to the side of one adjacent support block 24 (the left support block 24 in Figure 2(a)). The other adjacent block 24 (the right support block 24 in Figure 2(a)) has a horizontal through hole formed along the conveying direction, and the other end of the connecting shaft 27 slides through this through hole. In this embodiment, the grip piece 3A and the movable element 16 on which it is provided are located on the upstream side in the conveying direction, and the grip piece 3B and the movable element 16 on which it is provided are located on the downstream side in the conveying direction. A large-diameter stopper portion 27A is formed at the other end of the connecting shaft 27 (the right end in Figure 2(a)), preventing the support block 24, which passes through the connecting shaft 27, from falling off the connecting shaft 27. When adjacent movable elements 18 move closer together or further apart, the connecting shaft 27 guides the adjacent pair of support blocks 24 and the pair of grip pieces 3A and 3B provided on their upper parts, allowing them to move closer together or further apart in the transport direction. Furthermore, in this embodiment, the support block 24 and the grip piece 3A (3B) above it are pivotable relative to the rotating shaft 23 and the movable element 16 located below it. As the pivotable support block 24, on which the grip pieces 3A and 3B are provided, moves along the connecting shaft 27, the gripper 3, consisting of the grip pieces 3A and 3B, holds the container 2 and moves along the corner of the circulating transport path R, ensuring that the orientation of the grip pieces 3A and 3B is kept parallel. The support block 24 may be fixedly attached to the movable element 16, and the connecting shaft 27 may not be provided.

[0013] A pair of adjacent grip pieces 3A and 3B are at the same height and face each other, and recesses are formed on their opposing surfaces for holding the body of the container 2 (see Figure 3). As shown in Figure 3, a concave space is formed at the tip of the mounting base 26, and two straight guide shafts 26A aligned with the conveying direction are attached there. Each of the grip pieces 3A and 3B has two guide holes 3Aa and 3Ba, respectively. By passing the guide shaft 26A through the guide holes 3Aa and 3Ba and positioning the grip pieces 3A and 3B, the grip pieces 3A and 3B can be moved along the guide shaft 26A. A connecting pin 29 is vertically attached to the base of each grip piece 3A and 3B, and the lower end of this connecting pin 29 protrudes downward, passing through the space between two guide shafts 26A attached to the mounting base 26. A tension spring 28 is attached across the upper end of the connecting pin 29 on the grip pieces 3A and 3B and across the upper surface of the base of each mounting base 26. A lever 32A is positioned horizontally near the mounting base 26 of the grip piece 3A, which is on the upstream side in the conveying direction. The upper small-diameter portion of the fixed shaft 25 passes through the through hole 32a in the center of this lever 32A. Similarly, a lever 32B is positioned horizontally near the mounting base 26 of the grip piece 3B, which is on the downstream side in the conveying direction. The upper small-diameter portion of the fixed shaft 25 passes through the through hole 32a in the center of this lever 32B (see Figure 2(c)). As a result, levers 32A and 32B can swing around the fixed shaft 25 as the center of rotation. An oval-shaped through hole 32b is drilled at one end of the levers 32A and 32B that are on the connecting shaft 27 side (tip side), and the connecting pin 29 of the grip piece 3A (3B) is inserted through this through hole 32b. In addition, engaging pieces 32Aa and 32Ba are attached to the rear ends of levers 32A and 32B, respectively. These engaging pieces 32Aa and 32Ba are provided at different heights so that they can be positioned in an overlapping position without colliding in the vertical position (Figure 2(a)). Thus, one lever 32A is linked to one grip piece 3A, and the other lever 32B is linked to the other grip piece 3B. When the levers 32A and 32B are swung horizontally around the fixed shaft 25, the pair of grip pieces 3A and 3B are guided by the guide shaft 26A of the mounting base 26 and become able to move horizontally on each movable element 16 in the direction of transporting the container 2. The grip pieces 3A and 3B are pulled toward the engaging pieces 32Aa and 32Ba of the levers 32A and 32B by the tension spring 28 mentioned above. Therefore, when the lever 32A is swung around the fixed shaft 25 as the pivot point, the grip piece 3A (3B) shown in Figure 3 alternately moves between a position where the left side of the base of the grip piece 3A (3B) abuts against the upstream mounting portion 26Ba (upstream contact portion) of the guide shaft 26A on the mounting base 26 (upstream end in the transport direction) and a position where the right side of the base of the grip piece 3A (3B) abuts against the downstream mounting portion 26Bb (downstream contact portion) of the guide shaft 26A on the mounting base 26 (downstream end in the transport direction) (see Figure 3). As a result, the grip pieces 3A and 3B alternately move between one moving end (upstream end in the transport direction) and the other moving end (downstream end in the transport direction) in the horizontal direction along the transport direction relative to the movable element 16 on which they are attached. In this embodiment, a locking mechanism 33 (positioning mechanism) is configured by a tension spring 28, a lever 32A (32B), a guide shaft 26A, an upstream mounting portion 26Ba, a downstream mounting portion 26Bb, etc., to position the grip pieces 3A and 3B at the upstream and downstream ends in the transport direction on the movable element 16. Next, a switching mechanism 35 for switching the stopping position when levers 32A and 32B are swung will be described. As shown in Figure 2(b), the switching mechanism 35 comprises a pair of upper and lower engaging members 36A and 36B, and a pair of upper and lower cylinders 37A and 37B for raising and lowering them. The cylinders 37A and 37B are located at an appropriate position on the transport path of engaging pieces 32Aa and 32Ba, in this embodiment at position X in Figure 1. The engaging member 36A is movable up and down by a cylinder 37A that is directed vertically upward, and the engaging member 36B is provided to be movable up and down by a cylinder 37B that is directed vertically downward. When the engaging member 36A is at its lowered end due to the cylinder 37A, the engaging member 36A is positioned below the engaging piece 32Aa of the lever 32A. When the engaging member 36A is raised to its upper end position by the cylinder 37A, the engaging member 32A becomes capable of engaging with the engaging piece 32Aa of the lever 32A. Furthermore, when the engaging member 36B is at its upper end due to the cylinder 37B, the engaging member 36B is positioned above the engaging piece 32Ba of the lever 32B. When the engaging member 36A is lowered to its lower end by the cylinder 37B, the engaging member 32B becomes capable of engaging with the engaging piece 32Ba of the lever 32B. The operation of cylinders 37A and 37B is controlled by the control device 11. The control device 11 controls the raising and lowering operation of cylinders 37A and 37B, thereby switching the engaging member 36A between a height position in which it engages with the engaging piece 32Aa of lever 32A and a height position in which it does not engage. Similarly, the control device 11 switches the engaging member 36B between a height position in which it engages with the engaging piece 32Ba of lever 32B and a height position in which it does not engage. Here, Figure 2(c) shows levers 32A and 32B when adjacent grip pieces 3A and 3B are fully open (separated). However, if the width of the container 2 being held in the transport direction changes, and grip piece 3A is moved downstream in the transport direction and grip piece 3B is moved upstream in the transport direction from the position shown in Figure 2(c) to narrow the distance between the two grip pieces 3A and 3B, then lever 32A must be rotated clockwise and lever 32B must be rotated counterclockwise. When rotating the lever 32A clockwise, first the engaging member 36A at position X is raised to a position where it engages with the engaging piece 32Aa of the lever 32A. Next, all the movable elements 16 on the circulating transport path R are moved in the direction of supply position A → filling position B → capping position C → inspection position D → discharge position E, so that the engaging piece 32Aa of the lever 32A engages with the engaging member 36A and causes the lever 32A to swing clockwise around the fixed shaft 25. Furthermore, when the lever 32B is rotated counterclockwise, the engaging member 36B is raised and lowered to a position where it engages with the engaging piece 32Ba of the lever 32B. Next, all the movable elements 16 on the circulating transport path R are moved in the opposite direction from before, that is, in the direction of supply position A → discharge position E → inspection position D → capping position C → filling position B, so that the engaging piece 32Ba of the lever 32B engages with the engaging member 36B and causes the lever 32B to swing counterclockwise around the fixed shaft 25. In this way, the grip pieces 3A and 3B are switched between the upstream end position and the downstream end position in the conveying direction. Furthermore, the engaging members 36A and 36B are mounted so as to be able to swing in the conveying direction, and when a load is applied, they swing to engage with the engaging pieces 32Aa and 32Ba, thereby reducing the load.

[0014] Figures 3(a) to 3(f) show specific examples of how the linear conveying device 6 and its gripper 3, configured as described above, can hold containers 2 of different sizes. First, when holding the smallest container 2 with the gripper 3, as shown in Figure 3(c), the grip piece 3A is positioned at the downstream end in the transport direction relative to the movable element 16 on which it is attached, and the grip piece 3B is positioned at the upstream end in the transport direction relative to the movable element 16 on which it is attached. Then, the movable elements 16, 16 on which the grip pieces 3A and 3B are attached are brought as close together as possible. This makes it possible to hold the smallest container 2 with the gripper 3. On the other hand, when the largest container 2 is to be held by the gripper 3, as shown in Figure 3(d), grip piece 3A is positioned at the upstream end in the transport direction relative to the movable element 16 on which it is provided, and grip piece 3B is positioned at the downstream end in the transport direction relative to the movable element 16 on which it is provided. Then, the movable elements 16, 16 on which these grip pieces 3A and grip piece 3B are provided are separated to the maximum distance. This makes it possible to hold the largest container 2 with the gripper 3. Furthermore, when holding containers 2 of intermediate sizes between the smallest container 2 and the largest container 2 with the gripper 3, the arrangement is as shown in Figures 3(a), 3(b), 3(e), and 3(f). Even when holding these intermediate containers 2 of different sizes, the gripper 3 can smoothly hold containers 2 of different sizes by adjusting the spacing between adjacent pairs of movable elements 16 in the transport direction, and by switching the positions of the grip pieces 3A and 3B on each movable element 16 to the upstream and downstream ends in the transport direction. Furthermore, as shown in Figures 3(b) and 3(e), both grip pieces 3A and 3B may be positioned on the upstream end side or the downstream end side relative to the movable element 16. Alternatively, magnets may be attached to the upstream mounting portion 26Ba and the downstream mounting portion 26Bb, and iron plates or magnets may be attached to the grip pieces 3A and 3B, so that the grip pieces 3A and 3B are positioned on the upstream mounting portion 26Ba and the downstream mounting portion 26Bb by magnetic force. In this case, the tension spring 28 is not required.

[0015] According to this embodiment configured as described above, it is possible to expand the versatility of the container 2 that can be held compared to a conventional gripper. Here, using Figures 4 and 5, we will compare and explain the differences in the range of application between the gripper of a conventional linear conveying device and the gripper 3 of this embodiment when filling liquid with multiple filling nozzles provided in the filling device. Note that the movable elements 16a and 16b in Figures 4 and 5 are assumed to be conveyed from left to right. In other words, Figure 4 shows the prior art, where Figure 4(a) shows the state in which adjacent movable elements 16a and 16b are brought as close together as possible to minimize the distance between the grippers 3, and Figure 4(b) shows the state in which adjacent movable elements 16a and 16b are separated as far apart as possible to maximize the distance between the grippers 3. Here, if the pitch of adjacent filling nozzles in the filling device is 180 mm, the width of each movable element 16a and 16b in the conveying direction is 5 mm, and the clearance when movable elements 16a and 16b are brought as close together is 5 mm, then the range of motion of movable elements 16a and 16b is 35 mm. Here, if we ignore the thickness of the grip pieces 3A and 3B and assume that they are both fixedly positioned in the center of the movable elements 16a and 16b, the size of the container 2 that can be held by the grip pieces 3A and 3B will be 55 to 125 mm. Compared to conventional grippers, this embodiment allows the grip pieces 3A and 3B to be moved in the transport direction relative to the movable element on which they are attached, thereby widening the range of container sizes that can be held by the gripper 3. Specifically, Figure 5 shows this embodiment, where Figure 5(a) shows the state in which the distance between the grippers 3 is minimized by bringing adjacent movable elements 16a and 16b as close together as possible, and Figure 5(b) shows the state in which the distance between the grippers 3 is maximized by separating adjacent movable elements 16a and 16b as far as possible. The dimensions of the movable elements 16a and 16b, the pitch of the filling nozzle, and other values ​​are the same as in Figure 4. As shown in Figure 5(a), when holding the smallest container 2, by positioning the grip piece 3A at the upstream end in the transport direction of the movable element 16a on which it is provided, and the grip piece 3B at the downstream end in the transport direction of the movable element 16b on which it is provided, and bringing adjacent movable elements close together with a clearance of 5 mm, it becomes possible to hold a container with a size of 5 mm. Furthermore, when holding the largest container 2, as shown in Figure 5(b), by positioning the grip piece 3A at the upstream end of the movable element 16a in the transport direction and the grip piece 3B at the downstream end of the movable element 16b in the transport direction, and separating adjacent movable elements to a maximum of 75 mm, it becomes possible to hold a container 2 of 175 mm. Therefore, according to this embodiment, even if there is a limit to the range of movement of the movable elements 16, 16 that move an adjacent pair of grip pieces 3A, 3B, it is possible to widen the range of use of the container 2 held by the gripper 3, thereby providing a linear conveying device 6 that is more versatile than conventional devices.

[0016] Next, Figures 6 to 8 show the configuration of the gripper 3 and related parts of a linear conveying device 1, which is a second embodiment of the present invention. In this second embodiment, a mounting plate 41 is connected to adjacent movable element blocks 24, covering them from above. Two pairs of inclined guide shafts 42A and 42B are erected on each mounting plate 41. A pair of guide holes are drilled at an angle in the vertical direction at the base of the grip piece 3A, and the pair of guide shafts 42A are slidably passed through these guide holes in the grip piece 3A. Similarly, a pair of guide holes are drilled at an angle in the vertical direction at the base of the grip piece 3B, and the pair of guide shafts 42B are slidably passed through these guide holes in the grip piece 3B. As a result, each grip piece 3A and 3B can move up and down on the movable element 16 on which they are installed. Positioning blocks 43A and 43B are fixed to the upper ends of the guide shafts 42A and 42B of each set. Iron plates 44 are attached to the lower surfaces of the positioning blocks 43A and 43B, the lower ends of the guide shafts 42A and 42B, and the upper surface of the mounting plate 41 (see Figure 7(a)). Furthermore, magnets 45 are embedded in the upper and lower surfaces of the base of each grip piece 3A and 3B, and these magnets 45 magnetically attach to either the upper or lower plate 44, thereby positioning the grip pieces 3A and 3B at either the upper or lower end (see Figure 7). In other words, the upper and lower surfaces of the base of each grip piece 3A and 3B serve as contact points that come into contact with the plate 44 at the upper or lower position. A gripper 3 is formed by grip pieces 3A and 3B provided on adjacent movable elements 16 to hold the container 2. The guide shaft 42B of one movable element 16 is inclined upward toward the downstream direction in the conveying direction. The guide shaft 42A of the other movable element 16 is inclined upward toward the upstream direction in the conveying direction, symmetrically to the guide shaft 42B. Therefore, when the gripper 3, consisting of grip piece 3A and grip piece 3B, is positioned at the upper ends of the guide shafts 42A and 42B while maintaining a constant distance between adjacent movable elements 16, 16, the distance between grip piece 3A and grip piece 3B becomes wider than when they are positioned at the lower ends, making it possible for the gripper 3 to hold a container 2 with a wide width in the transport direction. Conversely, when the grip pieces 3A and grip piece 3B are positioned at the lower ends of the guide shafts 42A and 42B, the distance between grip piece 3A and grip piece 3B becomes narrower than when they are positioned at the upper ends, making it possible for the gripper 3 to hold a container 2 with a narrow width in the transport direction. In other words, in this second embodiment as well, the grip pieces 3A and 3B are moved in the transport direction relative to the movable element 16 on which they are provided. In this second embodiment, the locking mechanism (positioning mechanism) is composed of magnets 45 embedded in the upper and lower surfaces of the base of the grip pieces 3A and 3B, and upper and lower plates 44 that are magnetically attached to these magnets 45. Alternatively, iron plates may be provided on the upper and lower surfaces of the grip pieces 3A and 3B, and magnets may be attached to the lower surfaces of the positioning blocks 43A and 43B and the upper surface of the mounting plate 41. Or, magnets may be attached to the upper and lower surfaces of the grip pieces 3A and 3B, the lower surfaces of the positioning blocks 43A and 43B, and the upper surface of the mounting plate 41. In this second embodiment, the switching mechanism 35 for switching the positions of the grip pieces 3A and 3B comprises a pair of cams 47A and 47B that are raised and lowered by cylinders 37A and 37B, and cam followers 48A and 48B attached to the bases of the grip pieces 3A and 3B. Cams 47A and 47B are provided at appropriate positions along the transport path of grip pieces 3A and 3B, and are arranged to engage with the cam followers 48A and 48B of the transported grip pieces 3A and 3B. Cam 47A can move grip pieces 3A and 3B from the upper end to the lower end, and cam 47B can move grip pieces 3A and 3B from the lower end position to the upper end position. When moving grip pieces 3A and 3B to the lowered end position, the cylinder 37A lowers the cam 47A and moves the movable element 16 toward the cam 47A to engage the cam followers 48A and 48B with the cam 47A (see Figures 7 and 8). Conversely, when moving grip pieces 3A and 3B to the raised end position, the cylinder 37B lowers the cam 47B and moves the movable element 16 toward the cam 47B to engage the cam followers 48A and 48B with the cam 47B (see Figures 7 and 8). The other basic configurations are the same as in the first embodiment described above. In this second embodiment, the corresponding components shown in Figures 1 to 3 are assigned the same component numbers as in the first embodiment. Even in this second embodiment with such a configuration, the grip pieces 3A and 3B can move in the transport direction relative to the movable element 16 on which they are attached, so the same operation and effect as in the first embodiment can be obtained in this second embodiment as well. In the second embodiment described above, the guide shafts 42A and 42B that guide the raising and lowering of the grip pieces 3A and 3B were inclined symmetrically, but this is not limited to this. For example, the guide shaft 42A may be inclined 15 degrees upstream in the conveying direction with respect to the vertical line, and the guide shaft 42B may be inclined 10 degrees downstream in the conveying direction with respect to the vertical line.

[0017] Furthermore, while the above embodiments apply the present invention to the linear conveying device 6 of the filling system 1 to hold and convey the container 2 with the gripper 3, the linear conveying device 6 can also be used to hold and convey articles other than the container 2 with the gripper 3. [Explanation of Symbols]

[0018] 2...Container (item) 3...Gripper 3A...Grip piece 3B...Grip piece 6…Linear transport device (material transport device) 16…Movement 18... Electromagnetic coil unit (stator) 33... Locking mechanism (positioning mechanism) 35…Switching mechanism

Claims

1. The device comprises a plurality of movable elements, a stator for linearly driving the movable elements along a predetermined transport path, and, of two adjacent movable elements, one grip piece provided on one movable element and the other grip piece provided on the other movable element. In an article conveying device in which a gripper is formed by the gripping pieces of the two movable elements described above to hold an article, and the two movable elements are moved synchronously to convey the article held by the gripper along the conveying path described above, The above-mentioned gripper is provided with each of the grip pieces so as to be movable in the direction of transport of the article relative to the movable element on which the grip piece is provided, and a positioning mechanism is provided to position each of the grip pieces in the direction of transport on the movable element on which the grip piece is provided. Furthermore, a switching mechanism is provided that operates the positioning mechanism to switch the position of the grip piece in the movable element. An article conveying device characterized in that, depending on the width of the article held by the gripper in the conveying direction, the switching mechanism activates the positioning mechanism to position one grip piece and the other grip piece on the upstream or downstream side in the conveying direction relative to the movable element.

2. A mounting base for attaching the grip piece is placed above the above movable element, The article conveying device according to claim 1, characterized in that the mounting base has an axis extending in the conveying direction, and the gripper is movably mounted on the axis.

3. The article conveying device according to claim 2, characterized in that the mounting base has an upstream contact portion that contacts a grip piece moving upstream in the conveying direction to determine the upstream position of the grip piece, and a downstream contact portion that contacts a grip piece moving downstream in the conveying direction to determine the downstream position of the grip piece.

4. An inclined shaft is erected on one of the adjacent movable elements, with its upper end tilted downstream in the conveying direction, and an inclined shaft is erected on the other movable element, with its upper end tilted upstream in the conveying direction. The article conveying device according to claim 1, characterized in that the grip piece is provided so as to be able to move up and down diagonally along the inclined axis.

5. The article conveying device according to claim 4, characterized in that it is provided with an upper contact portion that contacts the upper surface of the grip piece located above the inclined axis and a lower contact portion that contacts the lower surface of the grip piece located below the inclined axis, a magnet is placed on at least one of the upper surface of the grip piece and the upper contact portion, and a magnet is placed on at least one of the lower surface of the grip piece and the lower contact portion, so that the grip piece can be magnetically attached to the upper contact portion and the lower contact portion.

Images