JP7733422B2 - packaging machine - Google Patents

Description

Article 30, Paragraph 2 of the Patent Act applies. Published at "Monozukuri Fair 2021" on October 13, 2021.

The present invention relates to a packaging machine that packages specified workpieces into bags that have one side that can be opened.

A conventional packaging machine that places workpieces into a specified bag is described in Patent Document 1. This packaging machine is equipped with a magazine that can store multiple bags stacked in the thickness direction, and a supply mechanism that removes bags from the magazine. The supply mechanism of this packaging machine is equipped with a suction pad that suction-holds the bags, a bag conveying mechanism that transports the suction pad from the magazine to a specified bag supply position, an opening pad that waits at the bag supply position and opens the transported bags, and a hollow cylindrical chute that can enter the open bag, and is configured to insert the workpieces into the bag after the chute enters the bag.

JP 2014-15228 A

However, the packaging machine described in Patent Document 1 has a hollow cylindrical chute that is relatively large enough to allow workpieces to pass through at all times. This means that depending on how open the bag opening is, the chute can come into contact with the bag opening. This can cause problems such as the bag becoming dislodged from the supply pad or opening pad and falling off, or the chute being unable to enter the bag, making it impossible to insert workpieces into the bag.

The present invention was created in light of the above-mentioned problems, and aims to provide a packaging machine configured to allow workpieces to be smoothly inserted. To achieve this objective, the present invention provides a packaging machine that inserts workpieces into bags configured with one side openable, comprising: a supply unit that supplies the bags in an open state; and a swivel unit that receives the bags from the supply unit. The swivel unit has a swivel member formed with a supply hole through which the workpieces can pass, and a swivel support attached to the swivel member, and is characterized in that the swivel support member enters the bag in a closed state while expanding the bag inside. Preferably, the swivel support member includes a pair of expansion rods that expand in a direction parallel to the bag and a pair of expansion plates that expand in a direction perpendicular to the bag. Preferably, the swivel member is configured to be rotatable about a predetermined support axis, and is configured to be swivelable so that the opening of the bag faces upward. Furthermore, the supply device preferably includes a supply pad that suction-holds the lower side of the bag, and an opening pad that suction-holds the upper side of the bag, and the opening pad suction-holds the opening side of the bag more closely than the suction pad.

The packaging machine of the present invention is equipped with a swivel support unit that can expand inside the bag. This swivel support unit is configured to enter the bag in a closed state and expand inside the bag, preventing the bag from falling out during insertion and greatly widening the bag's opening. These features offer advantages such as smooth workpiece insertion. Furthermore, the expansion rod and expansion plate expand the bag's opening in all directions, preventing workpiece spillage. Furthermore, because the swivel member is rotatable, bags supplied in any orientation, including horizontal, can be rotated to the desired orientation, enabling the use of a wide range of supply units. Furthermore, the supply unit's opening pad is offset toward the opening from the supply pad, allowing the bag to be opened smoothly while preventing the upper surface of the opening from drooping. This prevents the swivel support unit from getting caught on the bag, even when the bag is supplied horizontally, providing advantages such as smooth insertion.

1 is a partially cross-sectional side view showing the structure of a packaging machine according to the present invention. 2 is a partial cross-sectional side view showing an operation of transitioning from the state of FIG. 1 to the next state; FIG. 3 is a partial cross-sectional side view showing an operation of transitioning from the state of FIG. 2 to the next state; FIG. 1A and 1B are plan views showing the structure of a packaging machine according to the present invention, in which FIG. 1A is a plan view showing a state in which a supply cylinder extends a piston rod, and FIG. 1B is a plan view showing a state in which a supply cylinder extends a piston rod. 2A and 2B are enlarged views of part A in FIG. 1 showing the operation of the supply unit of the packaging machine according to the present invention, in which (a) is an enlarged side view of the main part showing the state in which a bag is being removed, (b) is an enlarged side view of the main part showing the state in which the bag is being transported, and (c) is an enlarged side view of the main part showing the state in which the gripping claws have opened the opening of the bag. 1 is a schematic front view showing the structure of a magazine of a packaging machine according to the present invention. 3A and 3B are enlarged views of part B in FIG. 2 showing the operation of the swivel unit of the packaging machine according to the present invention, in which (a) is an enlarged side view of the main part showing the swivel member in a vertical state, and (b) is an enlarged side view of the main part showing the swivel member in a horizontal state. 5A and 5B are enlarged views of part C in FIG. 4 showing the operation of the rotating unit of the packaging machine according to the present invention, in which (a) is an enlarged plan view of the main part showing the state in which the spreading rod is closed, and (b) is an enlarged plan view of the main part showing the state in which the spreading rod is open. 1A and 1B are explanatory diagrams showing the operation of the gripping unit of the packaging machine according to the present invention, in which (a) is an enlarged plan view of the essential parts showing the state before the gripping unit grips the bag, (b) is an enlarged plan view of the essential parts showing the state after the gripping unit grips the bag, (c) is an enlarged plan view of the essential parts showing the state when the bag is sealed by the sealing unit, and (d) is an enlarged view of part D in (b) showing the state of the side edge of the gripped bag. 10A and 10B are operation explanation sections showing another embodiment of the swivel unit of the packaging machine according to the present invention, in which (a) is an enlarged side view of the main part showing the state in which the oscillating cylinder is contracted, and (b) is an enlarged side view of the main part showing the state in which the oscillating cylinder is extended.

An embodiment of the present invention will now be described with reference to the drawings. In Figures 1 to 9, reference numeral 10 denotes a packaging machine that places predetermined workpieces (not shown) into bags H. As shown in Figure 1, this packaging machine 10 comprises a supply unit 20 capable of supplying bags H one by one; a turning unit 40 disposed in front of the supply unit 20 and rotating the bags H supplied from the supply unit 20 into a vertical position; a gripping unit 50 that grips the bags H that have been rotated into a vertical position by the turning unit 40; a sealing unit 60 that seals the bags H; and a control unit (not shown) that controls the operation of each mechanism. The supply unit 20 also comprises a magazine 21 that can store a large number of bags H and a conveying unit 31 that conveys the bags H in the magazine 21 toward the turning unit 40.

The bag H is a rectangular flat bag formed by folding a resin film, and has a folded short side H1 (hereinafter referred to as the bottom H1), two long sides H2, H2 (hereinafter referred to as the lateral edges H2, H2) adjacent to the bottom H1 that have been sealed in advance by heat welding or the like, and an unsealed short side H3 (hereinafter referred to as the opening H3) facing the bottom H1. The bag H is stored in the magazine 21 in a horizontal position with the opening H3 facing forward.

The magazine 21 of the supply unit 20 is configured to store multiple horizontally arranged bags H stacked in the thickness direction, and includes a bottom 22 that supports the bags H from below and a frame 26 that supports the bags H from the sides. The bottom 22 of the magazine 21 has a support plate 23 fixed to the base 11 of the packaging machine 10. Fixed to the support plate 23 are side support members 241, 241 that are configured to be approximately the same size as the front-to-rear dimension of the bags H in the front-to-rear direction. The side support members 241, 241 are cylindrical and are positioned with a predetermined gap between them so that they abut the lateral side edges H2, H2 of the bags H. A plate-shaped rear support member 242, slightly thinner in diameter than the side support members 241, 241, is disposed between the side support members 241, 241. The rear support member 242 is set to be less than half the front-to-rear dimension of the bag H and is positioned so as to be able to support the bottom H1 of the bag. With this structure, the bag H placed in the magazine 21 has its lateral side edges H2, H2 supported by the side support members 241, 241, while its lateral center portion curves downward and this curved portion abuts against the rear support member 242. Note that the vicinity of the opening H3 of the bag H that is not supported by the rear support member 242 is raised above the support plate 23, forming a gap therebetween. In addition, the support plate 23 and the base 11 are formed with a notched groove 25 (hereinafter referred to as the pad passage path 25) at a position corresponding to the lateral center of the bag, and this pad passage 25 is configured so that a supply pad 331 (described later) can move freely back and forth and up and down. The support plate 23 and pad passage 25 extend to the vicinity of the swivel unit 40 located in front, and as shown in Figure 4(b), when the bag H is supported by the swivel unit 40 (described below), the front end of the support plate 23 is configured to be able to support both ends of the bottom H1 of the bag H.

Meanwhile, the frame portion 26 has a pair of side walls 27, 27 that support the bag H from both lateral sides. These side walls 27, 27 are fixed to the base 11, with their upper ends positioned higher than the uppermost bag H and their rear ends bent inward, allowing them to support the bag H from behind. A restricting member 28 is attached to the front ends of the side walls 27, 27. This restricting member 28 is a plate that supports the bag H from the front and has a through hole 281 formed in the center of its lower end. The lateral dimension of this through hole 281 is slightly shorter than the lateral dimension of the bag H and its height is slightly longer than the diameter of the side support members 241, 241, with a restricting protrusion 282 formed in its center. This restricting protrusion 282 extends from the top of the passing hole 281 into the pad passing path 25, horizontally dividing the passing hole 281 and being sufficiently narrower than the pad passing path 25, allowing bags H with their horizontal center portion curved downward to pass through, as shown in FIG. 6. With this configuration, only the lowest bag H, whose horizontal center portion has been pulled downward by the supply pad 331 of the conveying unit 31 (described below), can pass through the passing hole 281 and pad passing path 25.

The magazine 21 also has a lid member 29 that is placed on top of the stored bags H. This lid member 29 is a plate that is the same shape as the bags H or smaller than the bags H, and a downwardly extending pressure protrusion 291 is formed on its underside. This pressure protrusion 291 is positioned opposite the supply pad 331, which will be described later, and presses downward near the opening H3 of the bag H. As a result, the lowest bag H will abut against the bottom 22 regardless of the number of bags H stored in the magazine 21.

The conveying section 31 of the supply unit 20 is equipped with a supply cylinder 32, an example of a reciprocating drive means, fixed to the underside of the base 11. This supply cylinder 32 is attached forward of the magazine 21 and is arranged so that its piston rod extends rearward. A lower suction section 33, which can reciprocate back and forth, is attached to the tip of the piston rod of the supply cylinder 32. This lower suction section 33 is provided with a suction pad 331 (hereinafter referred to as the supply pad 331) located below the pad passage 25 and a supply pad lifting section 332 that lifts the supply pad 331 toward the bag H. A suction means such as a vacuum generator is connected to the supply pad 331. The lower suction unit 33 configured in this manner allows the supply pad 331 to be raised and lowered directly below the magazine 21 by the drive of the supply pad lifting unit 332, and to move back and forth below the magazine 21 and the swivel unit 40 by the drive of the supply cylinder 32, making it possible to extract the lowest bag H from the magazine 21 and supply it to the swivel unit 40. The stroke of the supply pad lifting unit 332 is sized so that when the drive rod is extended, the supply pad 331 is positioned above the upper ends of the side support members 241, 241, and when the drive rod is retracted, the supply pad 331 is positioned below the lower end of the restricting protrusion 282.

A sliding rod 34 extending in the front-to-rear direction is fixed to the base 11, and an upper suction portion 35 is attached to the sliding rod 34 so that it can slide along the sliding rod 34. The upper suction portion 35 is provided with a suction pad 351 (hereinafter referred to as the opening pad 351) located above the pad passage path 25 and an opening pad lifting portion 352 that lowers the opening pad 351 toward the pad passage path 25, and a suction means such as a vacuum generator is connected to the opening pad 351. The upper suction portion 35 is connected to the lower suction portion 33 via a connecting spring 36 and is configured to follow the front-to-rear movement of the lower suction portion 33, and the sliding rod 34 is provided with a stop portion 341 that abuts the upper suction portion 35 before it hits the magazine 21. As a result, the upper suction portion 35 moves back and forth in the front-to-rear direction in response to the lower suction portion 33 until it abuts against the stop portion 341, and then waits in front of the magazine 21 after abutting against the stop portion 341, as shown in Figure 4(a). Note that the opening pad 351 is positioned slightly forward of the supply pad 331 of the lower suction portion 33 when it is driven.

The conveying unit 31 configured as described above is capable of opening the opening H3 of the bag H by moving the supply pad 331 and the opening pad 351 toward and away from each other after the lower suction unit 33 has extracted the bottom bag H from the magazine 21 as described above. The supply cylinder 32 is then driven to move the bag H with its opening H3 open toward the turning unit 40.

The swivel unit 40 includes a swivel member 41 disposed below the hopper 12 fixed to the base 11, and a swing cylinder 47, which is an example of a swing drive source that swings the swivel member 41. The swivel member 41 is configured to rotate around support shafts 46, 46 fixed to the base 11, and has a supply hole 42 formed longitudinally that is large enough for the workpiece. This supply hole 42 is configured to communicate with the hopper 12 when the swivel member 41 is in a vertical position, and is configured to guide workpieces passing through the hopper 12 downward. Meanwhile, the swing cylinder 47 is attached to the underside of the base 11, and the swivel member 41 is connected to the tip of its piston rod via a connecting member 471 that allows for angle change. The stroke of this swing cylinder 47 is dimensioned so that when the piston rod is extended, the swivel member 41 assumes a horizontal position facing the magazine 21 as shown in Figure 1, and when the piston rod is retracted, the swivel member 41 assumes a vertical position as shown in Figure 2. The hopper 12 is configured in a funnel shape that allows workpieces to pass through, and its upper opening is provided with a work supply device (not shown) that can feed a predetermined amount of workpieces into the hopper 12.

The outer surface of the swivel member 41 is provided with a swivel support portion 43 that supports the bags H supplied from the supply unit 20. This swivel support portion 43 is composed of a pair of spreading rods 44, 44 that can swing parallel to the bags H and a pair of spreading plates 451, 452 that can swing perpendicular to the bags H. The spreading plates 451, 452 and spreading rods 44, 44 are designed so that their tips protrude outward in the rotational direction (away from the support shafts 46, 46) beyond the tip of the swivel member 41. The spreading rods 44, 44 are biased in the direction that their tips open by a compression spring (not shown) provided between them and the swivel member 41, and the spreading plates 451, 452 are composed of leaf springs that bias their tips in the direction that they open. Meanwhile, a pair of pressure cylinders 48, 48 are attached to the base 11 with a predetermined gap therebetween so as to sandwich the horizontally positioned swivel member 41, and these pressure cylinders 48, 48 are arranged so that their piston rods abut against the spreader rods 44, 44. The base 11 is provided with a pressure pin 491 configured to be able to press the spreader plate 451 from above when the swivel member 41 is in the horizontal position, and the connecting member 471 is provided with a pressure pin 492 configured to be able to press the spreader plate 452 from below when the swivel member 41 is in the horizontal position. Therefore, the spreader rods 44, 44 and the spreader plates 451, 452 are pressed in the closing direction by the pressure cylinders 48, 48 and the pressure pins 491, 492. As a result, when the spreader rods 44, 44 and spreader plates 451, 452 are pressed by the pressure cylinders 48, 48 and pressure pins 491, 492, they wait in a closed state on the path of the bag H, but when the pressure cylinders 48, 48 and pressure pins 491, 492 are released, they spread open and are able to support the bag H. With this structure, the swivel unit 40 can support horizontally positioned bags H supplied from the supply unit 20 and can also rotate the bags H 90 degrees to a vertical position.

The gripping unit 50 is composed of an elevating cylinder 51 that extends and retracts a piston rod vertically upward, and a gripping part 52 fixed to the tip of the piston rod of the elevating cylinder 51. As shown in Figure 9(a), the gripping part 52 is provided with guide rods 53, 53 extending laterally, and a pair of slide blocks 54, 54 that slide along the guide rods 53, 53. The slide blocks 54, 54 are connected to each other so that they can move toward and away from each other by a claw reciprocating cylinder 55 that extends and retracts the piston rod laterally. Claw fixing plates 56, 56 are attached to the slide blocks 54, 54 via a slide table that is configured to slide freely back and forth. Attached to the upper surface of the claw fixing plate 56 are gripping claws 57, 57 that grip the bag H that has been verticalized by the swivel unit 40, and claw opening/closing drives 58, 58 that drive the gripping claws 57, 57 to open and close. The gripping claw 57 is composed of a fixed claw 571 fixed to the claw fixing plates 56, 56, and an opening/closing claw 572 that opens and closes relative to the fixed claw 571, with unevenness formed on the opposing surfaces of the fixed claw 571 and the opening/closing claw 572. In this embodiment, the opening/closing claw 572 is constantly biased by a claw spring in a direction that moves its tip away from the fixed claw 571, while the tip approaches the fixed claw 571 when driven by the claw opening/closing drive unit 58.

The stroke of the claw reciprocating cylinder 55 is configured so that when its piston rod is extended, the distance between the gripping claws 57, 57 is wider than the width of the bag H, as shown in Figure 9(a), while when its piston rod is retracted, the claw fixing plates 56, 56 abut against the spreader rods 44, 44, as shown in Figure 9(b). The claw fixing plates 56, 56 are constantly biased rearward, allowing the gripping claws 57, 57 to grip bags H in a vertical position, and the bags H gripped by the gripping claws 57, 57 wait at a predetermined position between the heater member 61 and the opposing member 62 of the sealing unit 60, described below. The gripping claws 57 and claw opening/closing drive units 58, 58 configured in this manner can move forward and backward using the slide table and can move closer and farther apart when driven by the claw reciprocating cylinder 55. Furthermore, the stroke of the lifting cylinder 51 is sized so that when the piston rod is extended, the gripping claws 57, 57 clamp the bag H together with the expansion rods 44, 44 of the swivel support part 43 that have entered the bag H, as shown in Figure 2, while when the piston rod is retracted, the swivel support part 43 comes out of the bag H, as shown in Figure 3.

The sealing unit 60 is composed of a heater member 61 positioned slightly above the gripping portion 52 when it reaches the lowered position, an opposing member 62 positioned opposite the heater member 61, and a sealing cylinder 63 that reciprocates the heater member 61 toward the opposing member 62. The heater member 61 is configured to be heated to a temperature at which the bag H can be welded when power is applied. The heater member 61 and opposing member 62 are positioned at a predetermined distance apart so that the bag H containing the work can pass through. The sealing cylinder 63 is configured to move the heater member 61 toward the opposing member 62 when the gripping portion 52 reaches the lowered position, so that the heater member 61 and opposing member 62 sandwich the opening H3 of the bag H. This welds the opening H3 of the bag H. A guide plate 64 is provided above the opposing member to ensure that the bag H, which is lowered by the gripping unit 50, is positioned between the heater member 61 and the opposing member 62. Furthermore, below the sealing unit 60, a discharge chute 70 is provided that discharges the bags H to a predetermined discharge position.

Next, the operation of the packaging machine 10 configured as above will be described.
First, in the standby state, the lower suction portion 33 is retracted to below the magazine 21, and the upper suction portion 35 is retracted by the tension spring 37 following the lower suction portion 33 until it abuts against the stop portion 341. When a drive signal is input in this state, the control unit drives the suction means and also drives the supply pad lifting unit 332 to raise and lower the supply pad 331 multiple times toward the lowest bag H. As the supply pad 331 is raised and lowered multiple times in this manner, swinging the bags H in the magazine 21 up and down, the bags H in the magazine 21 are released from their fixed state in which their lateral centers are bent downward, allowing them to be smoothly removed. Furthermore, the suction means is driven, and the supply pad 331 adsorbs the lowermost bag H against which it abuts, so that the lowermost bag H is pulled downward as the supply pad 331 descends. At this time, the side support members 241, 241 and the rear support member 242 form a gap between the vicinity of the opening H3 of the bag H and the support plate 23, allowing the vicinity of the opening H3 of the bag H to move freely by the gap, allowing the suction pad 331 to pull downward only the vicinity of the opening H3 of the lowest bag H. As a result, the center portion of the opening H3 of the lowest bag H is pulled downward below the lower end of the restricting protrusion 282, as shown by the two-dot chain line in FIG. 6 , and the corners between the opening H3 and the lateral side edges H2, H2 disengage from the side support members 241, 241, bending the bag H into a shape that allows it to pass through the passage hole 281. Thereafter, the supply cylinder 32 is driven to advance the supply pad 331. At this time, the lowest bag H, because it is bent as described above, can pass through the passage hole 281 without being locked by the restricting member 28, while the bags H in the next and subsequent rows are locked by the restricting member 28. As a result, the next bag H does not come out at the same time as the bottom bag H, and only the bottom bag H can be pulled out of the magazine 21. As described above, when the opening H3 of the bag H is pulled down by the supply pad 331, the side edges H2, H2 are pulled toward the center by the amount that the opening H3 is lowered, causing slack in the upper surface of the bag H near the opening H3. However, this slack portion of the upper surface is pressed down by the bags H in the next or subsequent rows above, or by the pressing protrusions 291 of the lid member 29, and slackens downward. Therefore, when the bag H is pulled down by the supply pad 331, the opening H3 can bend to the aforementioned state without opening, and the upper surface of the bag H does not get caught on the restricting protrusions 282, allowing it to pass smoothly through the passage hole 281. Furthermore, as described above, the side edges H2, H2 of the lowest bag H are pulled toward the center, and the corners on the opening H3 side are released from the side support members 241, 241, so that the weight of the bags H stacked above them is not placed on those corners, and the contact area with the bag H in the next tier directly above is reduced. This reduces friction with the lowest bag H, making it possible to pull it out smoothly. After passing through the passage hole 281 in this way, the bag H, with its side edges H2, H2 supported by the support plates 23, 23, is driven by the supply cylinder 32 and moves toward the turning unit 40.

After the bag H is pulled out of the magazine 21 as described above, the control unit further drives the supply cylinder 32 to move the lower suction unit 33 forward toward the swivel unit 40. After the lower suction unit 31, which has begun moving toward the swivel unit 40, reaches below the upper suction unit 35, the control unit drives the suction means to enable suction of the opening pad as well, and drives the supply pad lifting/lowering unit 332 and the opening pad lifting/lowering unit 352 to bring the supply pad 331 and the opening pad 351 closer together. As a result, when the opening pad 351 also suctions and holds the bag H, as shown in Figure 5(b), the control unit again drives the supply pad lifting/lowering unit 332 and the opening pad lifting/lowering unit 352 to separate the supply pad 331 and the opening pad 351, thereby opening the bag H. At this time, as mentioned above, the opening pad 351 is misaligned with the supply pad 331, and the area around the opening H3 opens while bending differently on the front and back sides. This distributes the force applied to the surface of the bag H, allowing it to open relatively smoothly. The opened bag H is then driven by the supply cylinder 32 and moves toward the rotating unit 40 located in front.

As described above, the bag H advances in an open state, covering the swivel support 43 of the swivel unit 40, which is waiting along its path of travel, as shown in Figure 5(c). At this time, the spreader rods 44, 44 and spreader plates 451, 452 of the swivel support 43 are sandwiched between the pressure cylinders 48, 48 and the pressure pins 491, 492, respectively, as shown in Figures 8(a) and 7(b), and are waiting in a closed state. This allows the bag H to be smoothly covered without the opening H3 getting caught on these. At this time, as described above, the opening pad 351 is offset forward from the supply pad 331, and suction-holds the opening H3 side of the bag H, preventing the upper surface of the opening H3 from drooping downward. As a result, when the bag H covers the swivel support 43, the swivel support 43 does not get caught on the opening H3, preventing the opening pad 351 from coming off the bag H or the bag H from being torn. When the bag H covers the spreader rods 44 and spreader plates 451 and 452 in this manner, the control unit retracts the presser cylinders 48, spreading the spreader rods 44 as shown in Figure 8(b). This causes the spreader rods 44 to abut against the lateral edge portions H2 of the inner surface of the bag H, supporting the bag H in a state in which it is opened laterally. The control unit then stops the suction means to remove the supply pad 331 and opening pad 351 from the bag H, and double-acts the supply cylinder 32 to move the lower suction portion 33 and upper suction portion 35 toward the magazine 21. After the lower suction portion 33 leaves the bag H, the control unit retracts the swing cylinder 47 to rotate the pivot member 41. At this time, as the rotating member 41 assumes a vertical position, the retaining pins 491, 492 are released from the spreader plates 451, 452, and the spreader plates 451, 452 gradually open, as shown in Figure 7(a). This tensions the opening H3 of the bag H between the spreader plates 451, 452 and the spreader rods 44, 44, preventing the bag from falling out during rotation. Furthermore, because the spreader rods 44, 44 and spreader plates 451, 452 remain inserted within the bag H during rotation, the bag H is not deformed by the effects of wind or the like during rotation, and can reliably reach between the gripping jaws 57, 57, as shown in Figure 9(a).

When the bag H reaches between the gripping claws 57, 57 as described above, the control unit drives the claw reciprocating cylinder 55 of the gripping unit 50 to move the gripping claws 57, 57 toward the bag H. As a result, the lateral edges H2, H2 of the bag H penetrate deeply between the gripping claws 57, 57, as shown in Figure 9(b), and the bag H is sandwiched between the spreading rod 44 and the claw fixing plate 56. At this time, because the gripping claws 57, 57 are configured to be movable in the front-to-rear direction by the slide table, the front-to-rear position of the gripping claws 57, 57 is corrected so that they align with the spreading rods 44, 44. After that, when the claw reciprocating cylinder 55 is fully retracted, the control unit drives the claw opening/closing drive units 58, 58 to close the gripping claws 57, 57. 9(d), the gripping unit 50 can firmly grip the bag H by pinching the periphery of the lateral edge H2 at three points: between the spreading rod 44 and the jaw fixing plate 56, between the spreading rod 44 and the fixed jaw 571, and between the spreading rod 44 and the opening/closing jaw 572. When the gripping jaws 57 grip the bag H in this way, the work supply device is driven to feed the work into the bag H via the hopper 12 and the supply hole 42 of the rotating means. At this time, the opening H3 of the bag H is widely opened in all directions by the spreading rod 44 and the spreading plates 451, 452, and the supply hole 42 is formed in the center of the spreading rod 44 and the spreading plates 451, 452 that open the opening H3, so the work is reliably guided into the bag H. Furthermore, because the gripping jaws 57 firmly grip the bag H together with the spreading rod 44 as described above, the bag H is less likely to slip, and a relatively large amount of work can be supplied. This results in a relatively clean product. Furthermore, the unevenness formed on the opposing surfaces of the gripping claws 57, 57 acts as an anti-slip surface, further preventing the bag H from slipping off.

Once a predetermined amount of workpieces has been supplied to the bag H as described above, the control unit drives the lifting cylinder 51 to lower the gripping claws 57, 57 until the opening H3 is positioned between the heater member 61 and the opposing member 62. This releases the bag H from the pivot support 43. When the opening H3 of the bag H reaches the gap between the heater member 61 and the opposing member 62, the control unit stops the lifting cylinder 51 and double-acts the claw reciprocating cylinder 55 to separate the gripping claws 57, 57, as shown in Figure 9(c). This causes the bag H gripped by the gripping claws 57, 57 to gradually expand laterally, stretching the opening H3. The control unit then drives the sealing cylinder 63 to move the heater member 61 toward the opposing member 62. As a result, the bag H is sandwiched between the heater member 61 and the opposing member 62, and the control unit energizes the heater member 61. As a result, the heater member 61 and the opening H3 of the bag H that contacts it are heated, and the opening H3 is welded. At this time, as described above, the gripping claws 57, 57 are configured to be slidable in the front-rear direction by the slide table and can move until the bag H contacts the opposing member 62. Therefore, the bag H can be sandwiched between the heater member 61 and the opposing member 62 simply by moving the heater member 61 toward the opposing member 62. As a result, a drive source for moving the opposing member 62 is not required, allowing for inexpensive manufacturing. Furthermore, as described above, the bag H is welded while the opening H3 is stretched laterally and taut, so no wrinkles are formed at the welded portion. Once the bag H is sealed in this manner, the control unit re-drives the sealing cylinder 63 to separate the heater member 61 from the bag H. At this time, the gripping claws 57, 57 continue to grip the bag H, allowing the heater member 61 to smoothly separate from the bag H. Furthermore, as described above, the jaw fixing plates 56, 56 are biased rearward. When the biasing force of the heater member 61 is released, the jaw fixing plates 56, 56, the gripping jaws 57, 57, and the bag H move rearward and smoothly separate from the opposing member 62. This prevents the bag H from remaining attached to the heater member 61 or the opposing member 62. The gripping unit 50 then double-acts the jaw opening/closing drive units 58, 58 to open the gripping jaws 57, 57. At this time, the jaw opening/closing drive units 58, 58 open and close the gripping jaws 57, 57 multiple times, ensuring that the bag H falls from the gripping jaws 57, 57. As a result, the bag H that has detached from the gripping jaws 57, 57 falls into the discharge chute 70 and is discharged to the specified discharge location, as shown by the two-dot chain line in FIG. 3.

Because the packaging machine 10 configured as described above is configured to transfer bags H from the supply unit 20 to the swivel unit 40, the supply unit 20 can retrieve the next tier of bags H from the magazine 21 while the swivel unit 40 is rotating the bags H and while the work is being inserted. Therefore, after the rotation and insertion processes are completed, the next tier of bags H can be immediately supplied when the swivel member 41 returns to its initial position. Similarly, because the packaging machine 10 is configured to transfer bags H from the swivel unit 40 to the gripping unit 50, the swivel unit 40 can receive and rotate the next tier of bags H from the supply unit 20 while the gripping unit 50 and sealing unit 60 are sealing the bags H. Because bags H are transferred between the supply unit 20 and the swivel unit 40 and between the swivel unit 40 and the gripping unit 50 in this manner, each mechanism can receive the next tier of bags H after transferring the bags H to the next process. As a result, the standby time of each mechanism is shortened, and the time per cycle is shortened, improving work efficiency. Furthermore, because the supply unit 20 is configured to remove the lowest bag H from the magazine 21, it is possible to remove bags H with the same operation regardless of the number of bags H remaining in the magazine 21. At this time, the lid member 29 is placed above the bag H, and this lid member 29 presses the bag H downward, preventing the bag H from floating even when there are only a few bags remaining, making it easier for the supply pad 331 to abut against the bag H. In particular, because the pressing protrusion 291 of the lid member 29 is formed in a position facing the supply pad 331, the pressing protrusion 291 and the supply pad 331 abut against the bag H so as to sandwich it between them. As a result, when the bag H abuts against the supply pad 331, it is prevented from bending upward and can be reliably sucked and held. Furthermore, because the configuration removes the lowest bag H from the magazine 21, there is no need to stop the packaging machine 10 when adding bags H to the magazine 21. This allows the packaging machine 10 to operate for longer periods of time, further improving work efficiency.

In the supply unit 20, the upper suction portion 35 and the lower suction portion 33 are connected by a connecting spring 36. Both the lower suction portion 33 and the upper suction portion 35 can be moved by driving the supply cylinder 32. This eliminates the need for position control using multiple drive sources, resulting in a relatively inexpensive configuration. Furthermore, the bag H removed from the supply unit magazine 21 is moved horizontally and handed over to the swivel unit 40 located on its path. Because the bag H rotates parallel to the radial direction of the support shaft 46 of the swivel unit 40, the range of motion of the bag H and the swivel unit 40 due to their rotation is relatively narrow. As a result, the packaging machine 10 can be made smaller. At the same time, unlike conventional packaging machines, there is no need to rotate piping such as an air intake hose connecting the suction pad that adsorbs the bag to the suction means simultaneously with the bag, which has the advantage of preventing the piping from getting caught on surrounding components.

The packaging machine 10 according to the present invention is not limited to the above-described configuration and can be modified in various ways without departing from the spirit of the invention. For example, in this embodiment, the bags H are rectangular flat bags with side edges H2, H2 welded together. However, flat bags with gussets around the perimeter or shapes other than rectangular are also acceptable, and it is preferable that the magazine 21 be modified appropriately to match the shape of the bags H. Furthermore, the supply cylinder 32, swing cylinder 47, pressure cylinder 48, lifting cylinder 51, claw reciprocating cylinder 55, and sealing cylinder 63 are examples of moving means for reciprocating various components. They are not limited to cylinders, and other moving means, such as a ball screw mechanism consisting of a ball screw and a drive nut threaded thereto, may also be acceptable. The arrangement of various drive sources may also be changed, such as by attaching the swing cylinder 47 forward of the pivoting member 41 as shown in FIG. 10 . If the swing cylinder 47 is attached forward of the pivoting member 41, the packaging machine 10 can be made smaller in the front-to-rear direction and installed in a smaller space.

H... bag H1... bottom H2... side edge H3... opening 10... packaging machine 11... base 12... hopper 20... supply unit 21... magazine 22... bottom 23... support plate 241... side support member 242... rear support member 25... pad passing path 26... frame 27... side wall 28... regulating member 281... passing hole 282... regulating protrusion 29... lid member 291... pressing protrusion 31... conveying section 32... supply cylinder 33... lower suction section 331... supply pad 332... supply pad lifting section 34... sliding rod 341... stopping section 35... upper suction section 351... opening pad 352... opening pad lifting section 36... LIST OF NUMERALS Connecting spring 40 Swivel unit 41 Swivel member 42 Supply hole 43 Swivel support portion 44 Spreading rod 451, 452 Spreading plate 46 Support shaft 47 Swing cylinder 471 Connecting part 48 Pressing cylinder 491, 492 Pressing pin 50 Grip unit 51 Lifting cylinder 52 Grip portion 53 Guide rod 54 Slide block 55 Jaw reciprocating cylinder 56 Jaw fixing plate 57 Grip jaw 571 Fixed jaw 572 Opening and closing jaw 58 Jaw opening and closing drive portion 60 Sealing unit 61 Heater member 62 Opposing member 63 Sealing cylinder 64 Guide plate 70 Discharge chute

Claims (3)

In a packaging machine in which a workpiece is placed inside a bag having one side that can be opened,
a supply unit that supplies the bag in an open state;
a turning unit that receives the bag from the supply unit;
The turning unit has a turning member formed with a supply hole through which the work can pass, and a turning support part attached to the turning member, and the turning support part is inserted into the bag in a closed state, and is expanded inside the bag,
A packaging machine characterized in that the pivot support portion includes a pair of spreading rods that spread the bag in a direction along the surface of the bag and a pair of spreading plates that spread the bag in a direction perpendicular to the bag. 2. The packaging machine according to claim 1 , wherein the pivoting member is configured to be rotatable about a predetermined support shaft, and is configured to be able to pivot so that the opening of the bag faces upward. 3. The packaging machine according to claim 1, wherein the supply unit includes a supply pad that suction-holds the lower side of the bag, and an opening pad that suction-holds the upper side of the bag, and the opening pad suction- holds the opening side of the bag more than the suction pad.