Box moving device

A box moving device is disclosed. The box moving device changes the position of a box having four side surfaces. The box moving device is equipped with a conveyor and a movement control unit. The movement control unit drives the conveyor to cause the box to move from a first position to a second position. The conveyor can alternately switch between a first state, in which it is contracted along a moving direction of the box, and a second state, in which it is extended along the moving direction of the box. The movement control unit causes the box to move from the first position to the second position by driving the conveyor that is in a holding mode in which it holds at least one of the side surfaces of the box and simultaneously switching the conveyor from the first state to the second state.

CROSS REFERENCE TO RELATED APPLICATIONS

This is the National Phase in the United States of PCT/JP2017/044342, filed Dec. 11, 2017, which claims priority to Japanese Patent Application No. 2017-050519, filed Mar. 15, 2017. Both of those applications are incorporated by reference herein in their entireties.

TECHNICAL FIELD

The present invention relates to a box moving device for changing the position of a box having four side surfaces that are connected to each other in a loop.

BACKGROUND ART

Conventionally, as disclosed in JP-A No. 2004-155428, a box packing apparatus for packing articles into boxes that are in a state in which their openings face the horizontal direction has been known. The box packing apparatus is equipped with a box moving device for moving, to the position at which the articles are packed, the boxes that have been conveyed thereto in the horizontal direction in a state in which their openings face the horizontal direction. The box moving device moves, to the position at which the articles are packed, the boxes by causing the boxes to drop to a predetermined position along the vertical direction, for example. In this case, the box moving device has a stopper for catching the boxes that have dropped to the predetermined position and stopping the movement of the boxes resulting from the drop.

BRIEF SUMMARY

However, in the box moving device that causes the boxes to drop along the vertical direction, in a case where the weight of the boxes is small, there is the concern that the boxes will stop midway before touching the stopper. Furthermore, in a case where the boxes are caused to drop while cover portions of the boxes move along a guide, there is the concern that the boxes will stop midway before touching the stopper because of the force that the guide receives from the cover portions. For that reason, the problem that the boxes do not reach the position at which the articles are packed, so that the articles cannot be packed normally into the boxes, has the potential to occur.

It is an object of the present invention to provide a highly reliable box moving device that moves a box to a predetermined position and inhibits the occurrence of the problem that the box does not reach the predetermined position.

A box moving device pertaining to the invention is a device for changing the position of a box having four side surfaces that are connected to each other in a loop. The box moving device is equipped with a conveyor and a movement control unit. The conveyor has at least a holding mode in which it holds at least one of the side surfaces of the box. The movement control unit drives the conveyor to cause the box to move along a moving direction from a first position to a second position. The conveyor can alternately switch between a first state, in which it is contracted along the moving direction, and a second state, in which it is extended along the moving direction. The movement control unit causes the box to move from the first position to the second position by driving the conveyor that is in the holding mode and simultaneously switching the conveyor from the first state to the second state.

The box moving device pertaining to the invention moves the box to the predetermined position by extending the conveyor in the direction in which it moves the box in a state in which the side surface of the box is being held by the conveyor. Because the box moving device uses the conveyor that can extend and contract in the moving direction of the box, the problem that the box is not conveyed normally to the predetermined position is inhibited. Consequently, with the box moving device pertaining to the invention, reliability can be improved.

Furthermore, in the box moving device pertaining to the invention, it is preferred that the movement control unit switch the conveyor from the first state to the second state by causing an end portion of the conveyor to move from the first position to the second position and switch the conveyor from the second state to the first state by causing the end portion of the conveyor to move from the second position to the first position.

In this case, the box moving device can cause the end portion of the conveyor on the side of the moving destination of the box to extend and contract toward the moving destination of the box. For that reason, the dimension of the conveyor in the moving direction of the box is kept down and a mechanism that moves the conveyor itself along the moving direction of the box becomes unnecessary. Consequently, with this box moving device, space for installing a device other than the conveyor can be ensured in the neighborhood of the box that has been conveyed by the conveyor.

Furthermore, in the box moving device pertaining to the invention, it is preferred that the conveyor further have a non-holding mode in which it does not hold the side surface. In this case, the movement control unit causes the box to move from the first position to the second position, then changes the conveyor from the holding mode to the non-holding mode, and then switches the conveyor from the second state to the first state.

In this case, the box moving device extends the conveyor to move the box to the predetermined position and then contracts the conveyor in the moving direction of the box in a state in which the side surface of the box is not being held by the conveyor. Consequently, this box moving device can prevent the box from being moved by the conveyor when the box moving device contracts the conveyor after having moved the box.

Furthermore, in the box moving device pertaining to the invention, it is preferred that the movement control unit cause the box to move from the first position to the second position by causing the box to move from above to below along the vertical direction in a state in which one of the four side surfaces of the box faces downward.

In this case, the box moving device can move the box to the predetermined position in a state in which the opening of the box faces sideways. Consequently, this box moving device can be utilized in, for example, a box packing apparatus for packing articles into boxes that have been conveyed by a conveyor.

Furthermore, it is preferred that the box moving device pertaining to the invention be further equipped with a flap guide. In this case, the box further has a flap that is a flat panel-shaped cover portion that extends from the side surface. The flap guide guides the flap while the movement control unit is causing the box to move from the first position to the second position.

In this case, the box moving device is equipped with the flap guide for regulating the position of the moving box by guiding the flap of the box. Consequently, this box moving device can prevent positional misalignment of the box that has been conveyed by the conveyor.

Furthermore, in the box moving device pertaining to the invention, it is preferred that in the holding mode the conveyor hold the two side surfaces that are along the moving direction.

In this case, the box moving device can stably move the box to the predetermined position by moving the box while holding, with the conveyor, the side surfaces on both sides of the box.

Furthermore, in the box moving device pertaining to the invention, it is preferred that the conveyor be a telescopic conveyor whose holding surface that holds the side surface can extend and contract in the moving direction.

In this case, because the box moving device uses the telescopic conveyor, the dimension of the conveyor in the moving direction of the box is kept down and a mechanism that moves the conveyor itself along the moving direction of the box becomes unnecessary. Consequently, with this box moving device, space for installing a device other than the conveyor can be ensured in the neighborhood of the box that has been conveyed by the conveyor.

The box moving device pertaining to the invention inhibits the occurrence of the problem that the box does not reach the predetermined position, so an improvement in reliability can be expected.

DETAILED DESCRIPTION

An embodiment of the invention will be described with reference to the drawings.

The embodiment described below is a specific example of the invention and is not intended to limit the technical scope of the invention.

(1) Configuration and Operation of Box Packing Apparatus

FIG. 1is a schematic view of a box packing apparatus10that uses a box moving device20pertaining to the embodiment of the invention. The box packing apparatus10is installed on a line in a food factory, for example, and is an apparatus for packing, into boxes, articles A that have been produced on the line in the food factory. The box packing apparatus10feeds, into a cardboard box C that has been placed in a location to which the articles A that are objects to be packed are delivered one after another, pluralities of the articles A through an opening Op of the cardboard box C to thereby pack the articles A. The articles A are bags in which a food such as potato chips has been packaged with a packaging material.

The box packing apparatus10is mainly equipped with a box forming unit1, a box packing unit2, and a box closing unit3.FIG. 1is a schematic front view of the box packing apparatus10.

In the following description, terms such as upper, lower, left, right, front (front), and rear (back) are used to describe directions and positions. These terms, unless otherwise specified, mean upper, lower, left, right, front, and rear indicated by arrows in the drawings.

(1-1) Box Forming Unit

The box forming unit1opens cardboard sheets S, which are the cardboard boxes C in a collapsed state, and closes and seals shut, with tape T, bottom covers B of the cardboard boxes C to thereby form the cardboard boxes C in which just one side thereof is open.FIG. 2is a view of the cardboard box C seen from the side of the closed bottom cover B. Flaps C21to C24on a top cover side opposite the bottom cover B are open outward. The open top cover side of the cardboard box C corresponds to the opening Op of the cardboard box C.

The cardboard boxes C that have been formed by the box forming unit1are conveyed by a conveyor (not shown in the drawings) to the box packing unit2. The box forming unit1delivers one after another the cardboard boxes C it has formed to the box packing unit2.

(1-2) Box Packing Unit

The box packing unit2feeds pluralities of the articles A into the cardboard boxes C to thereby pack the articles A.FIGS. 3A to 3Fare drawings for describing the operation of the box packing unit2. InFIGS. 3A to 3F, three articles A are sequentially fed, starting from the lower side, into a cardboard box C by the box packing unit2.FIG. 3Ashows a state just before the first article A is fed into the cardboard box C.FIG. 3Bshows a state just after the first article A has been fed into the cardboard box C.FIG. 3Cshows a state just before the second article A is fed into the cardboard box C.FIG. 3Dshows a state just after the second article A has been fed into the cardboard box C.FIG. 3Eshows a state just before the third article A is fed into the cardboard box C.FIG. 3Fshows a state just after the third article A has been fed into the cardboard box C.

The cardboard boxes C that are in a state in which their openings Op face sideways are supplied by the conveyor of the box forming unit1to the box packing unit2. Specifically, the cardboard boxes C having the bottom covers B formed on the front side of the box packing apparatus10and the openings Op formed on the back side of the box packing apparatus10are supplied to the box packing unit2.

As shown inFIG. 2, the cardboard box C used in the box packing apparatus10has four side surfaces C11to C14which are connected to each other in a loop, and eight flat panel-shaped flaps C21to C28, which extend forward and rearward from the four side surfaces C11to C14. The flap C21and the flap C25extend from the back side and the front side, respectively, of the side surface C11. The flap C22and the flap C26extend from the back side and the front side, respectively, of the side surface C12. The flap C23and the flap C27extend from the back side and the front side, respectively, of the side surface C13. The flap C24and the flap C28extend from the back side and the front side, respectively, of the side surface C14.

At the point in time when the cardboard box C is supplied to the box packing unit2, the flaps C25to C28on the front side of the box packing apparatus10have been closed by the box forming unit1and sealed shut with the tape T, so that the bottom cover B is formed. Also, at the point in time when the cardboard box C is supplied to the box packing unit2, the flaps C21to C24on the back side of the box packing apparatus10are open outward. That is, the cardboard box C is supplied to the box packing unit2with its opening Op facing rearward. The cardboard box C is supplied to the box packing unit2in a state in which the side surface C14faces downward as shown inFIG. 2.

The box packing unit2mainly has the box moving device20, a supporting and moving mechanism30, a feed mechanism50, a shutter mechanism60, a spill prevention mechanism70, an article conveyance mechanism80, and a box conveyance mechanism90.

The box moving device20moves, to a predetermined position, the cardboard boxes C that are supplied one after another from the box forming unit1. The box moving device20moves the cardboard boxes C from above to below in the vertical direction. The detailed configuration of the box moving device20will be described later.

The supporting and moving mechanism30supports, at the location where the articles A are packed into the cardboard box C, the cardboard box C that has been moved by the box moving device20. Furthermore, the supporting and moving mechanism30moves the cardboard box C into which the articles C have been packed from the location where the articles A were packed onto a conveyor belt of the box conveyance mechanism90.

The feed mechanism50feeds, into the cardboard box C being supported by the supporting and moving mechanism30and through the opening Op of the cardboard box C, the articles A that are conveyed thereto by the article conveyance mechanism80. The feed mechanism50uses a push plate to push the articles A forward to thereby feed the articles A into the cardboard box C.

The shutter mechanism60uses a shutter61to inhibit the articles A that have already been fed into the cardboard box C from obstructing the feeding of the articles A when the articles A are fed into the cardboard box C. The shutter mechanism60uses a pneumatic cylinder or the like to insert the shutter61into the cardboard box C and remove the shutter61from the cardboard box C.

The spill prevention mechanism70prevents the articles A that have already been fed into the cardboard box C from spilling out from the cardboard box C, which is in a state in which its opening Op faces sideways.

The article conveyance mechanism80conveys the articles A before the articles A become packed into the cardboard box C. The article conveyance mechanism80conveys the articles A with a conveyor belt at a predetermined timing so that the articles A are conveyed in front of the push plate of the feed mechanism50.

The box conveyance mechanism90conveys in the horizontal direction with a conveyor belt, and supplies to the box closing unit3, the cardboard box C that has been moved by the supporting and moving mechanism30and which is in a state in which its opening Op faces upward.

(1-3) Box Closing Unit

The box closing unit3closes, and seals shut with tape or the like, the flaps C21to C24of the cardboard box C that is supplied from the box conveyance mechanism90of the box packing unit2and whose opening Op faces upward to thereby form the top cover. The cardboard box C in which the top cover has been formed by the box closing unit3is conveyed out from the box packing apparatus10.

(2) Configuration of Box Moving Device

The box moving device20of the present embodiment mainly has a pair of conveyors21,22and a movement control unit23. Below, each of the pair of conveyors21,22is called a first conveyor21and a second conveyor22as needed.FIG. 4andFIG. 5are schematic perspective views of the box moving device20.FIG. 4shows a state before the conveyors21,22move a cardboard box C downward.FIG. 5shows a state after the conveyors21,22have moved the cardboard box C downward.FIG. 6is a front view of the box moving device20shown inFIG. 4.FIG. 7is a front view of the box moving device20shown inFIG. 5.FIG. 8is a block configuration diagram of the box moving device20.

The conveyors21,22move the cardboard box C from above to below in the vertical direction as a result of being driven while they hold the side surfaces of the cardboard box C. That is, the moving direction of the cardboard box C is parallel to the vertical direction. InFIG. 6andFIG. 7, the rotational directions of the conveyors21,22are indicated by arrows. The cardboard box C that is moved by the conveyors21,22has the side surface C14facing downward, the side surface C13facing leftward, the side surface C12facing upward, the side surface C11facing rightward, the bottom cover B facing forward, and the opening Op facing rearward.

The first conveyor21is disposed on the left side of the cardboard box C, and the second conveyor22is disposed on the right side of the cardboard box C. That is, the first conveyor21opposes the side surface C13of the cardboard box C, and the second conveyor22opposes the side surface C11of the cardboard box C.

The conveyors21,22are a type of belt conveyor called a telescopic conveyor or a shuttle conveyor in which the length of the conveyor can be extended and contracted. The conveyors21,22can extend and contract along the vertical direction.

The first conveyor21is a belt conveyor in which a first endless belt21eis entrained about one first follower roller21a, two first drive rollers21b, a first main guide roller21c, and a first auxiliary guide roller21d. The first follower roller21ais positioned on the right side of the two first drive rollers21b. The first main guide roller21cis positioned on the right side of the first auxiliary guide roller21d. The first main guide roller21cand the first auxiliary guide roller21dare rollers for changing the length of the first conveyor21. Between the first follower roller21aand the first main guide roller21c, the right-side surface of the first endless belt21eopposes the side surface C13of the cardboard box C. When the first conveyor21is driven, the first endless belt21emoves from above to below between the first follower roller21aand the first main guide roller21c.

The second conveyor22is a belt conveyor in which a second endless belt22eis entrained about one second follower roller22a, two second drive rollers22b, a second main guide roller22c, and a second auxiliary guide roller22d. The second follower roller22ais positioned on the left side of the two second drive rollers22b. The second main guide roller22cis positioned on the left side of the second auxiliary guide roller22d. The second main guide roller22cand the second auxiliary guide roller22dare rollers for changing the length of the second conveyor22. Between the second follower roller22aand the second main guide roller22c, the left-side surface of the second endless belt22eopposes the side surface C11of the cardboard box C. When the second conveyor22is driven, the second endless belt22emoves from above to below between the second follower roller22aand the second main guide roller22c.

The first conveyor21has the same length as the second conveyor22and is installed in the same position as the second conveyor22in the vertical direction. The conveyors21,22each have a holding mode and a non-holding mode. The holding mode is a mode in which the conveyors21,22hold the side surfaces C11, C13of the cardboard box C. The non-holding mode is a mode in which the conveyors21,22do not hold the side surfaces C11, C13of the cardboard box C.

When the first conveyor21is in the holding mode, the right-side surface of the first endless belt21etouches the side surface C13of the cardboard box C between the first follower roller21aand the first main guide roller21c. When the first conveyor21is driven, the first endless belt21emoves from above to below between the first follower roller21aand the first main guide roller21c. Because of this, a force from above to below in the vertical direction acts on the cardboard box C being held by the first conveyor21. Conversely, when the first conveyor21is in the non-holding mode, the right-side surface of the first endless belt21edoes not touch the side surface C13of the cardboard box C between the first follower roller21aand the first main guide roller21c. For that reason, when the first conveyor21is in the non-holding mode, the force does not act on the cardboard box C even if the first conveyor21is driven.

When the second conveyor22is in the holding mode, the left-side surface of the second endless belt22etouches the side surface C11of the cardboard box C between the second follower roller22aand the second main guide roller22c. When the second conveyor22is driven, the second endless belt22emoves from above to below between the second follower roller22aand the second main guide roller22c. Because of this, a force from above to below in the vertical direction acts on the cardboard box C being held by the second conveyor22. Conversely, when the second conveyor22is in the non-holding mode, the left-side surface of the second endless belt22edoes not touch the side surface C11of the cardboard box C between the second follower roller22aand the second main guide roller22c. For that reason, when the second conveyor22is in the non-holding mode, the force does not act on the cardboard box C even if the second conveyor22is driven.

In the first conveyor21, the vertical direction length of the right-side surface of the first endless belt21ebetween the first follower roller21aand the first main guide roller21cis called a first effective holding length L1. In the second conveyor22, the vertical direction length of the left-side surface of the second endless belt22ebetween the second follower roller22aand the second main guide roller22cis called a second effective holding length L2. The first effective holding length L1and the second effective holding length L2are the vertical direction dimensions of the sections where the first conveyor21and the second conveyor22can hold the side surfaces of the cardboard box C.

The first conveyor21and the second conveyor22shown inFIG. 4andFIG. 6are respectively in a state in which the first effective holding length L1and the second effective holding length L2are at their shortest. The first conveyor21and the second conveyor22shown inFIG. 5andFIG. 7are respectively in a state in which the first effective holding length L1and the second effective holding length L2are at their longest. The range that the first effective holding length L1and the second effective holding length L2can take is appropriately set on the basis of, for example, the dimensions of the cardboard box C and the specifications of the box packing apparatus10.

(2-2) Movement Control Unit

As shown inFIG. 8, the movement control unit23is connected to the first conveyor21and the second conveyor22and controls the first conveyor21and the second conveyor22. The movement control unit23is a computer configured from a CPU, a ROM, and a RAM, for example.

The movement control unit23has a first conveyor driver23a, a second conveyor driver23b, a first effective holding length changer23c, a second effective holding length changer23d, a first mode switcher23e, and a second mode switcher23f, which are programs stored in the ROM or the like and executed. In other words, these elements are sets of machine-readable instructions, stored on non-transitory memory in the movement control unit23that, when executed, cause the movement control unit23to perform the functions described.

The first conveyor driver23acontrols the first drive rollers21bof the first conveyor21. For example, the first conveyor driver23acan cause the first drive rollers21bto rotate at a predetermined rotational speed. Because of this, the first conveyor driver23acan cause the first endless belt21eto rotate in the direction shown inFIG. 6andFIG. 7to drive the first conveyor21.

The second conveyor driver23bcontrols the second drive rollers22bof the second conveyor22. For example, the second conveyor driver23bcan cause the second drive rollers22bto rotate at a predetermined rotational speed. Because of this, the second conveyor driver23bcan cause the second endless belt22eto rotate in the direction shown inFIG. 6andFIG. 7to drive the second conveyor22.

The first effective holding length changer23ccontrols the first main guide roller21cand the first auxiliary guide roller21dof the first conveyor21. The first effective holding length changer23cchanges the vertical direction positions of the first main guide roller21cand the first auxiliary guide roller21dto adjust the first effective holding length L1of the first conveyor21. Specifically, the first effective holding length changer23cchanges the first effective holding length L1by using a pneumatic cylinder or the like to cause the first main guide roller21cand the first auxiliary guide roller21dto move the same distance in the same direction.

The second effective holding length changer23dcontrols the second main guide roller22cand the second auxiliary guide roller22dof the second conveyor22. The second effective holding length changer23dchanges the vertical direction positions of the second main guide roller22cand the second auxiliary guide roller22dto adjust the second effective holding length L2of the second conveyor22. Specifically, the second effective holding length changer23dchanges the second effective holding length L2by using a pneumatic cylinder or the like to cause the second main guide roller22cand the first auxiliary guide roller22dto move the same distance in the same direction.

The first mode switcher23ealternately switches the first conveyor21between the holding mode and the non-holding mode. When switching the first conveyor21from the holding mode to the non-holding mode, the first mode switcher23ecauses the entire first conveyor21to move a predetermined distance leftward. Because of this, the right-side surface of the first endless belt21eof the first conveyor21moves away from, to a position at which it cannot touch, the side surface C13of the cardboard box C. Conversely, when switching the first conveyor21from the non-holding mode to the holding mode, the first mode switcher23ecauses the entire first conveyor21to move a predetermined distance rightward. Because of this, the right-side surface of the first endless belt21eof the first conveyor21moves toward, to a position at which it can touch, the side surface C13of the cardboard box C.

The second mode switcher23falternately switches the second conveyor22between the holding mode and the non-holding mode. When switching the second conveyor22from the holding mode to the non-holding mode, the second mode switcher23fcauses the entire second conveyor22to move a predetermined distance rightward. Because of this, the left-side surface of the second endless belt22eof the second conveyor22moves away from, to a position at which it cannot touch, the side surface C11of the cardboard box C. Conversely, when switching the second conveyor22from the non-holding mode to the holding mode, the second mode switcher23fcauses the entire second conveyor22to move a predetermined distance leftward. Because of this, the left-side surface of the second endless belt22eof the second conveyor22moves toward, to a position at which it can touch, the side surface C11of the cardboard box C.

The movement control unit23causes the cardboard box C to move to the predetermined position from above to below in the vertical direction, as described next, by executing at predetermined timings the first conveyor driver23a, the second conveyor driver23b, the first effective holding length changer23c, the second effective holding length changer23d, the first mode switcher23e, and the second mode switcher23.

(3) Operation of Box Moving Device

An operation where the box moving device20moves, from above to below in the vertical direction, one cardboard box C that has been supplied from the box forming unit1to until the cardboard box C becomes supported by the supporting and moving mechanism30will be described using the drawings.FIGS. 9 to 12are drawings for describing the operation of the box moving device20.FIGS. 9 to 12are front views of the box moving device20. The state of the box moving device20changes in the order ofFIG. 9,FIG. 10,FIG. 11, andFIG. 12and then returns toFIG. 9in the process of moving the cardboard box C. The movement control unit23respectively drives, with the first conveyor driver23aand the second conveyor driver23b, the first conveyor21and the second conveyor22while the box packing apparatus10is being driven. That is, in the states shown inFIGS. 9 to 12, the first endless belt21eand the second endless belt22eare always being driven. InFIG. 9andFIG. 10, the first effective holding length L1of the first conveyor21and the second effective holding length L2of the second conveyor22are at their shortest as shown inFIG. 6. InFIG. 11andFIG. 12, the first effective holding length L1of the first conveyor21and the second effective holding length L2of the second conveyor22are at their longest as shown inFIG. 7.

FIG. 9shows a state just before the cardboard box C that has been supplied from the box forming unit1becomes held by the conveyors21,22. The cardboard box C is positioned in the neighborhood of the vertical direction upper portions of the conveyors21,22. The conveyors21,22are in the non-holding mode. That is, the first endless belt21eof the first conveyor21is not touching the side surface C13of the cardboard box C, and the second endless belt22eof the second conveyor22is not touching the side surface C11of the cardboard box C.

In the state shown inFIG. 9, the movement control unit23uses the first mode switcher23eand the second mode switcher23to respectively cause the first conveyor21and the second conveyor22to transition from the non-holding mode to the holding mode. Because of this, the conveyors21,22transition to the state shown inFIG. 10.

FIG. 10shows a state just after the cardboard box C that has been supplied from the box forming unit1has become held by the conveyors21,22. The cardboard box C is positioned in the neighborhood of the vertical direction upper portions of the conveyors21,22. The conveyors21,22are in the holding mode. That is, the first endless belt21eof the first conveyor21is touching the side surface C13of the cardboard box C, and the second endless belt22eof the second conveyor22is touching the side surface C11of the cardboard box C.

In the state shown inFIG. 10, the movement control unit23uses the first effective holding length changer23cand the second effective holding length changer23dto respectively lengthen the first effective holding length L1of the first conveyor21and the second effective holding length L2of the second conveyor22. Because of this, the cardboard box C is conveyed downward in the vertical direction as a result of being held by the conveyors21,22in the holding mode, and at the same time the first conveyor21and the second conveyor22extend downward in the vertical direction. For that reason, the cardboard box C is conveyed to the neighborhood of the vertical direction lower portions of the conveyors21,22extended in the vertical direction. The cardboard box C that has been conveyed becomes supported by the supporting and moving mechanism30. Because of this, the conveyors21,22transition to the state shown inFIG. 11.

FIG. 11shows a state just after the cardboard box C has been conveyed downward in the vertical direction by the conveyors21,22to a position where it becomes supported by the supporting and moving mechanism30. The cardboard box C is positioned in the neighborhood of the vertical direction lower portions of the conveyors21,22. The conveyors21,22are in the holding mode.

In the state shown inFIG. 11, the movement control unit23uses the first mode switcher23eand the second mode switcher23to respectively cause the first conveyor21and the second conveyor22to transition from the holding mode to the non-holding mode. Because of this, the conveyors21,22transition to the state shown inFIG. 12.

FIG. 12shows a state just after the cardboard box C has been conveyed downward in the vertical direction by the conveyors21,22to the position where it becomes supported by the supporting and moving mechanism30. The cardboard box C is positioned in the neighborhood of the vertical direction lower portions of the conveyors21,22. The conveyors21,22are in the non-holding mode.

In the state shown inFIG. 12, the movement control unit23uses the first effective holding length changer23cand the second effective holding length changer23dto respectively shorten the first effective holding length L1of the first conveyor21and the second effective holding length L2of the second conveyor22. Because of this, the first effective holding length L1and the second effective holding length L2shorten to the state shown inFIG. 9. Because of this, the conveyors21,22transition to the state shown inFIG. 9. In the process of transitioning fromFIG. 12toFIG. 9, the conveyors21,22are in the non-holding mode, so the cardboard box C is not conveyed by the conveyors21,22.

FIG. 13is a timing chart of control of constituent elements of the movement control unit23. As shown inFIG. 13, the first conveyor driver23aand the second conveyor driver23bare synchronously controlled, the first effective holding length changer23cand the second effective holding length changer23dare synchronously controlled, and the first mode switcher23eand the second mode switcher23are synchronously controlled. That is, the movement control unit23controls the first conveyor21and the second conveyor22in the same way at the same timings. The states shown inFIGS. 9 to 12respectively correspond to the states at times t1to t4inFIG. 13.

The first conveyor driver23aand the second conveyor driver23bcan each take an “ON” state, in which they drive the first conveyor21and the second conveyor22, and an “OFF” state, in which they do not drive the first conveyor21and the second conveyor22. InFIG. 13, the first conveyor driver23aand the second conveyor driver23bare always in the “ON” state. That is, the first endless belt21eof the first conveyor21and the second endless belt22eof the second conveyor22are always being driven.

The first effective holding length changer23cand the second effective holding length changer23dcan each take an arbitrary state between a “shortest” state, in which the first effective holding length L1and the second effective holding length L2are at their shortest, and a “longest” state, in which the first effective holding length L1and the second effective holding length L2are at their longest. The range that the first effective holding length L1and the second effective holding length L2, which is the range from the shortest to the longest, can take is appropriately set on the basis of, for example, the dimensions of the cardboard boxes C and the specifications of the box packing apparatus10. InFIG. 13, the first effective holding length changer23cand the second effective holding length changer23dtransition between “shortest” and “longest.”

The first mode switcher23eand the second mode switcher23can each take the “holding mode” and the “non-holding mode” of the first conveyor21and the second conveyor22. InFIG. 13, the first mode switcher23eand the second mode switcher23transition between the “holding mode” and the “non-holding mode.”

The box packing apparatus10is a device for changing the vertical direction position of the cardboard box C having the four side surfaces C11to C14that are connected to each other in a loop. The box packing apparatus10is equipped with the conveyors21,22for conveying the cardboard box C downward in the vertical direction and the movement control unit23for controlling the operation of the conveyors21,22. The movement control unit23causes the cardboard box C to move from above to below in the vertical direction by driving the conveyors21,22that are in the holding mode and simultaneously switching the conveyors21,22from a state in which are contracted along the vertical direction (FIG. 10) to a state in which they are extended along the vertical direction (FIG. 11). The movement control unit23can alternately switch the conveyors21,22between the state in which they are contracted and the state in which they are extended.

The box moving device20moves the cardboard box C to the predetermined position by extending the conveyors21,22in the direction in which they move the cardboard box C (downward in the vertical direction) in a state in which the side surfaces C13, C11of the cardboard box C are being respectively held by the conveyors21,22. As shown inFIG. 6andFIG. 7, the movement control unit23can extend and contract the conveyors21,22in the vertical direction by adjusting the first effective holding length L1of the first conveyor21and the second effective holding length L2of the second conveyor22.

In this way, by using the conveyors21,22that can extend and contract in the moving direction of the cardboard box C while they hold the cardboard box C, the box moving device20can move, with the conveyors21,22, the cardboard box C to the predetermined position in a state in which the cardboard box C is held by the conveyors21,22. Because of this, the box moving device20can inhibit the problem that the cardboard box C is not conveyed normally to the predetermined position. For that reason, the occurrence of the problem that the moving of the cardboard box C stops midway before the cardboard box C reaches the position where it becomes supported by the moving and supporting mechanism30, so that as a result the articles A are not fed normally into the cardboard box C, is inhibited.

Consequently, the box moving device20inhibits the occurrence of the problem that the cardboard box C does not reach the predetermined position, so an improvement in the reliability of the box moving device20can be expected.

In the box moving device20, the movement control unit23lengthens the first effective holding length L1and the second effective holding length L2to extend the conveyors21,22in the vertical direction by causing the first main guide roller21cand the second main guide roller22cto move downward in the vertical direction. Conversely, the movement control unit23shortens the first effective holding length L1and the second effective holding length L2to contract the conveyors21,22in the vertical direction by causing the first main guide roller21cand the second main guide roller22cto move upward in the vertical direction. The first main guide roller21cand the second main guide roller22ccorrespond to end portions of the conveyors21,22on the side of the moving destination of the cardboard box C (the lower side).

In this way, the box moving device20can cause the conveyors21,22to extend and contract downward in the vertical direction, which is the moving destination of the cardboard box C. Because of this, the box moving device20does not need to use conveyors with long lengths that extend as far as the neighborhood of the predetermined position to convey the cardboard box C to the predetermined position. For that reason, the dimension of the conveyors21,22(the length of the conveyors21,22) in the vertical direction, which is the moving direction of the cardboard box C, is kept down and a large-scale mechanism that moves the conveyors21,22themselves along the moving direction of the cardboard box C becomes unnecessary.

Consequently, with the box moving device20, space for installing a device other than the conveyors21,22can be ensured in the neighborhood of the cardboard box C that has been conveyed by the conveyors21,22. For that reason, for example, space for installing the feed mechanism50and the shutter mechanism60, which are used for packing the articles A into the cardboard boxes C, can be sufficiently ensured under the conveyors21,22.

In the box moving device20, the conveyors21,22each have the non-holding mode in which they do not hold the side surfaces C13, C11of the cardboard box C. The movement control unit23drives the conveyors21,22and simultaneously causes the conveyors21,22to extend downward in the vertical direction to move the cardboard box C, then changes the conveyors21,22from the holding mode to the non-holding mode, and then causes the conveyors21,22to contract in the vertical direction.

Because of this, the box moving device20can move, with the conveyors21,22, the cardboard box C to the predetermined position and then, in a state in which the side surfaces C13, C11of the cardboard box C are not being respectively held by the conveyors21,22, return the first effective holding length L and the second effective holding length L2to the state before the cardboard box C was moved (FIG. 9).

Consequently, the box moving device20can prevent the problem that the cardboard box C ends up being held and moved by the conveyors21,22when the conveyors21,22become contracted after they have moved the cardboard box C.

Furthermore, just after the box moving device20conveys the cardboard box C to the predetermined position and changes the conveyors21,22from the holding mode to the non-holding mode (FIG. 12), the next cardboard box C that has been supplied from the box forming unit1can be set between the conveyors21,22as shown inFIG. 9. Because of this, just after the cardboard box C has been conveyed by the supporting and moving mechanism30to the box conveyance mechanism90, the box moving device20can prepare to hold, with the conveyors21,22, the next cardboard box C. Consequently, the box moving device20can efficiently convey the cardboard boxes C and can improve the capacity of the box packing apparatus10.

The box moving device20can move the cardboard box C from above to below along the vertical direction in a state in which the side surface C14, which is one of the four side surfaces C11to C14of the cardboard box C, faces downward. Because of this, the box moving device20can move the cardboard box C to the predetermined position in a state in which the opening Op of the cardboard box C faces sideways (rearward).

Consequently, the box moving device10can be utilized in the box packing apparatus10for packing the articles A in the horizontal direction into the cardboard boxes C that have been conveyed by the conveyors21,22.

In the box moving device20, telescopic conveyors whose holding surfaces that hold the side surfaces C13, C11of the cardboard box C can extend and contract in the moving direction of the cardboard box C are used as the conveyors21,22. The holding surfaces are the right-side surface of the first endless belt21eof the first conveyor21, which touches the side surface C13of the cardboard box C, and the left-side surface of the second endless belt22eof the second conveyor22, which touches the side surface C11of the cardboard box C.

Because of this, the box moving device20can cause the conveyors21,22to extend and contract downward in the vertical direction, which is the moving destination of the cardboard box C. For that reason, the dimension of the conveyors21,22(the length of the conveyors21,22) in the vertical direction, which is the moving direction of the cardboard box C, is kept down and a large-scale mechanism that moves the conveyors21,22themselves along the moving direction of the cardboard box C becomes unnecessary. Consequently, with the box moving device20, space for installing a device other than the conveyors21,22can be ensured in the neighborhood of the cardboard box C that has been conveyed by the conveyors21,22.

Furthermore, the box moving device10can stably move the cardboard box C to the predetermined position by moving the cardboard box C while holding, with the conveyors21,22, the side surfaces C13, C11on both sides of the cardboard box C.

The speed at which the cardboard box C is moved by the box moving device20is equal to the speed of the first endless belt21eof the first conveyor21and the second endless belt22eof the second conveyor22. Furthermore, the speed at which the cardboard box C is moved by the box moving device20is independent of the extension/contraction speed (the speed at which the first effective holding length L1and the second effective holding length L2change) and the extension/contraction timing (the timing when the first effective holding length L1and the second effective holding length L2change) of the first conveyor21and the second conveyor22. For that reason, it is not necessary to strictly synchronize the extension/contraction speed and the extension/contraction timing of the first conveyor21and the second conveyor22. Consequently, inexpensive mechanisms such as pneumatic cylinders can be employed as the drive source for changing the positions of the first main guide roller21cand the first auxiliary guide roller21dof the first conveyor21and the drive source for changing the positions of the second main guide roller22cand the second auxiliary guide roller22dof the second conveyor22.

(5) Example Modifications

An embodiment of the invention has been described above, but the invention is not limited to the above embodiment and can be changed in various ways in a range that does not depart from the spirit thereof.

(5-1) Example Modification A

It is preferred that the box moving device20of the embodiment be further equipped with a flap guide30. While the box moving device20is moving the cardboard box C downward in the vertical direction, the flaps C21to C24of the cardboard box C, which are located on the back side of box packing apparatus10, are open outward. The flap guide30guides the flaps C21to C24of the cardboard box C to regulate the front and rear direction and right and left direction position of the cardboard box C while the box moving device20is moving the cardboard box C downward in the vertical direction.

The flap guide30has a structure that can guide, along the vertical direction, at least one of the flaps C21to C24of the cardboard box C.FIG. 14shows an example of the flap guide30of the present example modification.FIG. 14is a schematic perspective view of the box moving device20equipped with the flap guide30. The flap guide30guides the flap C21on the right side of the cardboard box C.

The flap guide30is installed on the vertical direction lower side of the right-side conveyor22. The flap guide30is mainly configured from a fixed guide portion31and a movable guide portion32. The fixed guide portion31is installed on the rear side of the flap C21of the cardboard box C that moves downward in the vertical direction. The fixed guide portion31is fixed in a predetermined position. The fixed guide portion31has a fixed guide surface31athat is orthogonal to the front and rear direction. The fixed guide surface31atouches the rear-side surface of the flap C21being guided by the flap guide30.

The movable guide portion32is installed on the vertical direction lower side of the right-side conveyor22so as to be movable in the front and rear direction and the right and left direction by a drive mechanism (not shown in the drawings). The movable guide portion32can, together with the fixed guide portion31, sandwich, on the front side of the fixed guide portion31, the flap C21of the cardboard box C that moves downward in the vertical direction. The movable guide portion32can have an arbitrary shape that can, together with the fixed guide portion31, sandwich the flap C21.

InFIG. 14, the flap C21of the cardboard box C moving downward in the vertical direction is sandwiched between the fixed guide portion31and the movable guide portion32, whereby movement of the flap C21in the front and rear direction and the right and left direction is regulated. Because of this, movement, in the front and rear direction and the right and left direction, of the cardboard box C21moving downward in the vertical direction is regulated by the flap guide30.

In this way, the flap guide30regulates the front and rear direction and right and left direction position of the moving cardboard box C by guiding the flap C21of the cardboard box C while the cardboard box C is being moved downward in the vertical direction by the movement control unit23. Consequently, the box moving device20can prevent, with the flap guide30, positional misalignment of the cardboard box C that has been conveyed by the conveyors21,22and can move the cardboard box C in a predetermined posture to the predetermined position. As a result, when the articles A are packed into the cardboard box C by the feed mechanism50, the problem that the articles A collide with the cardboard box C because of positional misalignment of the cardboard box C, so that the cardboard box C moves in the horizontal direction, is inhibited.

Furthermore, inFIG. 14, the flap guide30guides the flap C21on the right side of the cardboard box C. However, the flap guide30may also guide the flap C23on the left side of the cardboard box C, or may also guide both the flaps C21, C23on both the right and left sides of the cardboard box C.

Furthermore, as mentioned above, with the box moving device20of the embodiment, space for installing a device other than the conveyors21,22can be ensured in the neighborhood of the cardboard box C that has been conveyed by the conveyors21,22. For that reason, in the present example modification, space for installing the flap guide30can be sufficiently ensured under the conveyors21,22.

Furthermore, the flap guide30may also have another structure that can guide at least one of the flaps C21to C24of the cardboard box C while the cardboard box C is being moved downward in the vertical direction by the movement control unit23. That is, the flap guide30can have an arbitrary structure for regulating the front and rear direction and right and left direction position of the cardboard box C moving downward in the vertical direction.

(5-2) Example Modification B

The box moving device20of the embodiment moves the cardboard box C to the predetermined position by extending the conveyors21,22in the direction in which they move the cardboard box C (downward in the vertical direction) in a state in which the side surfaces C13, C11of the cardboard box C are being respectively held by the conveyors21,22. In this way, the box moving device20moves the cardboard box C by respectively holding, with the conveyors21,22, the two side surfaces C13, C11of the four side surfaces C11to C13of the cardboard box C.

However, the box moving device20may also move the cardboard box C to the predetermined position in a state in which at least one of the four side surfaces C11to C13of the cardboard box C is held. For example, the box moving device20may also move the cardboard box C by holding, with the conveyor21, just the side surface C13on the left side of the cardboard box C. Furthermore, the box moving device20may also move the cardboard box C by holding, with the conveyor22, just the side surface C11on the right side of the cardboard box C. In these cases, it is preferred that the side surface not held by the conveyors21,22out of the side surfaces C13, C11on both the right and left sides of the cardboard box C be guided by an arbitrary guide member while the cardboard box C is moving downward.

FIG. 15is a schematic perspective view of a box moving device120in the present example modification. InFIG. 15, a conveyor122is installed on the right side of the cardboard box C and a conveyance roller121is installed on the left side of the cardboard box C. The conveyor122has the same structure and function as the conveyor22of the embodiment. That is, the conveyor122has a holding mode and a non-holding mode.

The conveyance roller121is fixed in a predetermined position. The conveyance roller121has plural rollers121adisposed along the vertical direction. The rollers121aare rollers with open cylinder shapes, for example. The rollers121aare disposed in such a way that the rotational axes of the open cylinder shapes are along the front and rear direction. That is, the rollers121aare rotatable along the vertical direction.

When the conveyor122is in the holding mode, the surface C13on the left side of the cardboard box C touches the rollers121aof the conveyance roller121. While the cardboard box C is being moved downward in the vertical direction by the conveyor122, the rollers121aof the conveyance roller121rotate while touching the side surface C13on the left side of the cardboard box C. In this way, the conveyance roller121guides the cardboard box C conveyed by the conveyor122, regulates the right and left direction position of the cardboard box C, and prevents positional misalignment of the cardboard box C.

It will be noted that, inFIG. 15a conveyor having the same structure and function as the conveyor21of the embodiment may also be installed on the left side of the cardboard box C, and a conveyance roller having the same structure and function as the conveyance roller121of the present example modification may also be installed on the right side of the cardboard box C.

(5-3) Example Modification C

The box moving device20of the embodiment moves the cardboard box C from above to below along the vertical direction in a state in which the side surface C14, which is one of the four side surfaces C11to C14of the cardboard box C, faces downward and the opening Op faces sideways (rearward). However, the orientation of the cardboard box C conveyed by the box moving device20and the moving direction of the cardboard box C can be appropriately changed depending on the apparatus in which the box moving device20is used.

For example, the box moving device20can also be applied to an apparatus that moves the cardboard box C along the horizontal direction in a state in which the bottom cover B of the cardboard box C faces downward and the opening Op faces upward. In this case, the positions and orientation of the conveyors21,22are appropriately changed in the box moving device20.

REFERENCE SIGNS LIST