Patent Description:
Conventionally, as a means of accumulating bag packages, a device is known which projects packages onto a conveyor and, while conveying the packages a fixed distance at a time, aligns the packages in such a way that the packages partially lie on top of each other. For example, <CIT> discloses a packing device that aligns plural bag packages to a state in which mutually adjacent packages partially overlap to thereby create a group in which a predetermined quantity of the packages are accumulated and conveys the group with conveying means so that the predetermined quantity of packages are together put into a predetermined box <CIT> discloses a package apparatus that includes a first conveyance unit and a second conveyance unit, wherein the first conveyance unit is configured and arranged to convey a plurality of packaged objects in a first conveying direction, and wherein the second conveyance unit is provided below the first conveyance unit and configured and arranged to convey the packaged objects in a second conveying direction generally opposite from the first conveying direction. <CIT> discloses a packing device according to the preamble of claim <NUM>.

Groups of the packages are conveyed by a downstream conveyor to a predetermined position, but as a preceding group is being conveyed by the downstream conveyor, the next group of packages is being formed by an upstream conveyor.

However, if the bags of the packages are greater than a predetermined size, sometimes when the downstream conveyor is conveying the preceding group the package at the front of the next group of packages sticks out from the downstream end of the upstream conveyor, contacts the downstream conveyor, and ends up being pulled onto the downstream conveyor, so that the line of accumulation becomes disarranged.

It is a problem of the present disclosure to provide a package accumulating device that accumulates even packages with a large bag size without disarranging the line.

As defined in appended claim <NUM>, a package accumulating device according to the invention conveys plural bag packages to a predetermined position while performing an accumulating operation that aligns the packages in such a way that parts of each of the packages lie on top of parts of adjacent packages in their thickness direction. The package accumulating device includes a first conveyor that comprises a conveyance surface for accumulating the packages, the first conveyor performing the accumulating operation with the conveyance surface, a second conveyor that comprises a conveyance surface, the second conveyor receiving and further conveying a group of the packages aligned by the first conveyor and being moved from the conveyance surface of the first conveyor onto the conveyance surface of the second conveyor, and a control unit. The control unit performs switching between a first state and a second state. The first state is a state in which a downstream end of the first conveyor in a conveyance direction of the conveyance surface and an upstream end in the conveyance direction of the conveyance surface of the second conveyor oppose each other when the second conveyor accepts the group of the packages from the conveyance surface of the first conveyor. The second state is a state in which the position of the upstream end of the conveyance surface of the second conveyor is lower than it is in the first state with respect to the downstream end of the conveyance surface of the first conveyor.

In this package accumulating device, the second state is a state in which the position of the upstream end of the second conveyor is lower than it is in the first state with respect to the downstream end of the first conveyor, so even if the package at the front of the next group of packages sticks out from the downstream end of the upstream conveyor, it is kept from contacting the conveyance direction upstream end of the second conveyor and is not pulled onto the downstream conveyor, and the line of accumulation is also inhibited from becoming disarranged.

Advantageously, in the first state the conveyance surface of the first conveyor and the conveyance surface of the second conveyor form a substantially continuous conveyance surface. In the second state the conveyance surface of the second conveyor is lower than the downstream end of the first conveyor.

In this package accumulating device, in the second state the continuity between the downstream end of the first conveyor and the upstream end of the second conveyor is eliminated and the position of the upstream end of the second conveyor is lower than it is in the first state, so even if the package at the front of the next group of packages sticks out from the downstream end of the upstream conveyor, it is kept from contacting the conveyance direction upstream end of the second conveyor and is not pulled onto the second conveyor, and the line of accumulation is also inhibited from becoming disarranged.

According to the invention, in the first state the conveyance surfaces of the first conveyor and the second conveyor are both inclined. In the second state the upstream end of the second conveyor is lowered so that the conveyance surface of the second conveyor becomes horizontal.

Advantageously, in this package accumulating device, in the second state, due to the upstream end of the second conveyor being lower, a package sticking out from the upstream end of the first conveyor does not contact the conveyance surface of the second conveyor as long as the center of gravity of the package remains on the conveyance surface of the first conveyor, so the package is not pulled onto the second conveyor, and the line of accumulation is also inhibited from becoming disarranged.

Said package accumulating device can optionally further include a third conveyor that accepts and conveys the group of the packages from the second conveyor.

In this package accumulating device, even when the second conveyor and the final conveyance position of the group of the packages are located away from each other, the group of the packages can be conveyed to the final conveyance position via the third conveyor.

Advantageously, the control unit causes the first conveyor to perform the accumulating operation by moving the conveyance surface of the first conveyor by a predetermined amount each time the packages come onto the conveyance surface of the first conveyor.

In this package accumulating device, the packages following after the package at the front of the group lie on top of each other in the same inclined posture and align.

Advantageously, the control unit moves the conveyance surface by an amount greater than the predetermined amount and simultaneously causes the second conveyor to operate.

In this package accumulating device, the last package of the group of the packages reliably moves from the conveyance surface of the first conveyor onto the conveyance surface of the second conveyor.

According to the invention, the control unit lowers the upstream end of the second conveyor after the last package of the group of the packages moves from the conveyance surface of the first conveyor onto the conveyance surface of the second conveyor.

In this package accumulating device, the upstream end of the second conveyor is lowered after the last package of the group of the packages moves from the conveyance surface of the first conveyor onto the conveyance surface of the secondconveyor, so it is difficult for the line of the group to become disarranged.

A package accumulating device pertaining to a fifth aspect of the disclosure is the package accumulating device pertaining to the invention or any one of the first aspect to the fourth aspect, wherein advantageously, the control unit decides whether or not to execute the switching to the second state depending on the bag size of the packages.

In this package accumulating device, in a case where the bag size is large, the package at the front of the next group sticks out from the downstream end of the first conveyor and contacts and becomes pulled onto the second conveyor that is conveying the preceding group, so switching to the second state in accordance with the bag size is sensical.

Advantageously, the control unit decides whether or not to execute the switching to the second state depending on the required production capacity.

In this package accumulating device, when the production speed is increased, formation of the "next group" is performed by the first conveyor while the second conveyor conveys the "preceding group," and it becomes easier for the package at the front of the "next group" to stick out from the downstream end of the first conveyor and contact and become pulled onto the second conveyor that is conveying the "preceding group. " For that reason, switching to the second state depending on the required production capacity is sensical.

In the package accumulating device according to the invention, the second state is a state in which the position of the upstream end of the conveyance surface of the second conveyor is lower than it is in the first state with respect to the downstream end of the conveyance surface of the first conveyor, so even if the package at the front of the next group of packages sticks out from the downstream end of the conveyance surface of the upstream conveyor, it is kept from contacting the conveyance direction upstream end of the second conveyor and is not pulled onto the downstream conveyor, and the line of accumulation is also inhibited from becoming disarranged.

An embodiment of the disclosure will be described below with reference to the drawings. It will be noted that the following embodiment is a specific example of the disclosure and is not intended to limit the technical scope of the disclosure.

<FIG> is a block diagram of a packing system <NUM> equipped with a case forming, packing, and sealing apparatus pertaining to an embodiment of the disclosure. Furthermore, <FIG> is a perspective view showing the configuration of the packing system, and <FIG> is a perspective view showing a flow of cardboard boxes B and products G in the packing system <NUM>.

In <FIG> and <FIG>, the packing system <NUM> is a system that packs a fixed number of bagged products (products G) such as snack foods, for example, in an aligned state and in multiple layers into cardboard boxes B.

As shown in <FIG> and <FIG>, the packing system <NUM> comprises a cardboard box handling area DHA and a product handling area GHA that are interconnected in a state in which they are mutually independently separable. The cardboard box handling area DHA includes two processes, a case forming process P1 and a packing process P3. The product handling area GHA includes a product aligning process P2.

That is, in the packing system <NUM>, because the cardboard box handling area DHA and the product handling area GHA are interconnected, the three processes of the case forming process P1, the product aligning process P2, and the packing process P3 work together.

The case forming process P1 is a process of erecting sheet-like cardboard box precursors Z into cardboard boxes B and conveying the cardboard boxes B to a packing position. The case forming process P1 is configured by a box precursor accommodating unit <NUM>, a case forming unit <NUM>, a first posture changing unit <NUM>, and a box downward conveying unit <NUM>.

The product aligning process P2 is a process of feeding to a predetermined position the products G supplied from an upstream process, aligning a fixed number of the products G so that adjacent products partially lie on top of each other, and conveying the fixed number of products G to the packing position. The product aligning process P2 is configured by a product feeding unit <NUM>, a product aligning unit <NUM>, and a product inserting unit <NUM>.

The packing process P3 is a process of packing, into the cardboard boxes B that have been conveyed thereto from the case forming process P1, the fixed quantity of products G that have finished being aligned in the product aligning process P2, closing the boxes, and conveying the boxes to a box discharge position. The packing process P3 is configured by a product receiving unit <NUM>, a second posture changing unit <NUM>, and a case sealing unit <NUM>.

The packing system <NUM> performs multilayer packing of the products G into the cardboard boxes B, and the posture of the products G inside the boxes B is a "standing posture. " That is, the standing posture is a posture where, when the openings of the boxes B face up, the front sides and the back sides of the products G face sideways, the upper and lower end portions of the products G face up and down, and the left and right side portions of the products G face sideways.

Furthermore, as shown in <FIG> and <FIG>, the cardboard box handling area DHA has a two-level structure, and the case forming process P1 and the packing process P3 are supported by a common frame <NUM>. The case forming process P1 occupies the second-level portion, and the packing process P3 occupies the first-level portion.

In order to realize this two-level structure, the conveyance direction of the cardboard boxes B from the erection of the cardboard boxes B by the case forming unit <NUM> to the box downward conveying unit <NUM> and the conveyance direction of the cardboard boxes B up to when the openings of the cardboard boxes B that have been packed with the products G are sealed by the case sealing unit <NUM> are mutually opposite directions.

As shown in <FIG>, the case forming process P1 is configured by the box precursor accommodating unit <NUM> that introduces the cardboard box precursors Z to the packing system <NUM>, the case forming unit <NUM> that erects the cardboard boxes B, the first posture changing unit <NUM> that rotates the cardboard boxes B <NUM>° about a horizontal axis orthogonal to the conveyance direction, and the box downward conveying unit <NUM> that conveys downward the cardboard boxes B that have been switched to a first posture.

The box precursor accommodating unit <NUM>, as shown in <FIG>, picks one at a time and transports upward the cardboard box precursor Z at the very front of the cardboard box precursors Z stacked in a supply position, rotates the transported cardboard box precursor Z <NUM>° about a vertical axis, and opens it into a tubular shape.

The cardboard box precursors Z are placed in the supply position by a worker. The cardboard box precursors Z are collapsed with their flaps Zf open and are stacked in a horizontal direction in a posture in which the flaps Zf are positioned in the vertical direction. It will be noted that for convenience of description the flaps Zf on the top surface side will be called top flaps Zfa and the flaps Zf on the bottom surface side will be called bottom flaps Zfb.

The upward transport of the cardboard box precursors Z is performed by a lift mechanism <NUM>. When all the cardboard box precursors Z in the supply position run out, a detection sensor (not shown in the drawings) sends a detection signal to a controller <NUM> (see <FIG>).

Furthermore, the rotation of the cardboard box precursors Z about the vertical axis is realized by sucking and holding, with suckers, the side surfaces of the cardboard box precursors Z with a sucking and rotating mechanism <NUM> and rotating the sucking and rotating mechanism <NUM><NUM>° about the vertical axis.

The case forming unit <NUM> conveys in a horizontal direction the cardboard box precursors Z that have been opened into a tubular shape and at the same time folds and tapes the bottom flaps Zfb of the cardboard box precursors Z to thereby erect the cardboard boxes B in a state in which the top flaps Zfa are open.

The first posture changing unit <NUM> rotates the cardboard boxes B <NUM>° in the conveyance direction. More specifically, the first posture changing unit <NUM> rotates the cardboard boxes B <NUM>° about a horizontal axis orthogonal to the conveyance direction to thereby change the posture of the cardboard boxes B to a posture (hereinafter called a first posture) in which the openings and the top flaps Zfa of the cardboard boxes B are in the same vertical plane. When the cardboard boxes B are in the first posture, the openings face the product handling area GHA.

The box downward conveying unit <NUM> conveys downward the cardboard boxes B that have been switched to the first posture. That is, the box downward conveying unit <NUM> moves the cardboard boxes B downward with the openings of the cardboard boxes B kept facing the product handling area GHA.

Disposed upstream of the product aligning process P2 in terms of the flow of the products G in the packing system <NUM> are a weigher, a bag-making and packaging machine, and the like not shown in the drawings. Only products G that have passed, for example, weight, seal, and contamination inspections in the upstream process are supplied to the product aligning process P2 in the packing system <NUM>.

The product aligning process P2 is configured by the product feeding unit <NUM> that accepts the products G and conveys them to a predetermined position, the product aligning unit <NUM> that aligns the products G supplied from the product feeding unit <NUM>, and the product inserting unit <NUM> that accumulates and pushes out the aligned products G.

The product feeding unit <NUM> has a product introducing conveyor <NUM> and a feeding conveyor <NUM>. The product introducing conveyor <NUM> receives, downstream of the process that performs, for example, the weight, seal, and contamination inspections, the supply of the products G that have passed the inspections and leads those products G to the feeding conveyor <NUM>.

The feeding conveyor <NUM> conveys to the product aligning unit <NUM> the products G conveyed thereto from the product introducing conveyor <NUM>.

<FIG> is a perspective view showing the arrangement of the feeding conveyor <NUM>, a first aligning conveyor <NUM>, and a second aligning conveyor <NUM>. In <FIG>, the conveyance surface of the feeding conveyor <NUM> is inclined with respect to a horizontal plane, and a support wall <NUM> that supports and prevents the products G from falling off and guides the products G in the conveyance direction is provided on the inclination direction lower side end of the conveyance surface. The products G that move on the inclination direction upper side of the conveyance surface receive a component force of the force of gravity along the inclination direction, so the products G slide down toward the support wall <NUM> while moving and thereafter move along the support wall <NUM>.

The product aligning unit <NUM> has the first aligning conveyor <NUM>, the second aligning conveyor <NUM>, and a third aligning conveyor <NUM>. The product aligning unit <NUM> is a unit that conveys the products G to a predetermined position while performing an accumulating operation with respect to the products G. The product aligning unit <NUM> is particularly suited to the accumulation of bag packages, so it can also be used independently as a package accumulating device.

The first aligning conveyor <NUM>, in order to receive the products G that drop thereto from the feeding conveyor <NUM>, has one end set in a lower position than the height of the distal end portion of the feeding conveyor <NUM> and has the other end set in the height position of the second aligning conveyor <NUM>.

It will be noted that it is preferred that the distal end portion of the feeding conveyor <NUM> be positioned in the space directly above the product placement surface of the first aligning conveyor <NUM>. Here, the product placement surface is the surface-of the conveyance surface of the first aligning conveyor <NUM>-that waits to receive the products G that drop thereto.

Additionally, each time the first aligning conveyor <NUM> catches one product G, it conveys the product G a fixed distance (pitch L) toward the second aligning conveyor <NUM>. This is because it is necessary to vacate the landing position before the next product G drops thereto because the position where the first aligning conveyor <NUM> catches the products G is the same. For that reason, the product G moves the fixed distance (pitch L) closer to the second aligning conveyor <NUM> from the position to which it dropped.

Part of the product G that drops thereafter lands on the first aligning conveyor <NUM>, while the remaining part leans against the preceding product G and becomes inclined. This operation of aligning plural products G in such a way that parts of each of the products G lie on top of parts of adjacent products G in their thickness direction is called an accumulating operation.

<FIG> is a front view of the product aligning unit <NUM>. In <FIG>, the product G at the front that was dropped first on the first aligning conveyor <NUM> has a subsequent product G partially lying on top of it, and thereafter another subsequent product G comes to lie on top of that subsequent product G to form a line.

In a case where, for example, the product aligning unit <NUM> aligns N=<NUM> products G as a group, the product G at the front is ahead a length of <NUM> from the position where the product G at the rear lands, so in the present embodiment at least the product G at the front of the line arrives on the second aligning conveyor <NUM>.

<FIG> is a front view of the product aligning unit <NUM> when the product G at the front of the aligned groups of products G has moved onto the second aligning conveyor <NUM>. In <FIG>, after the product G at the rear of the line lands on the first aligning conveyor <NUM>, the first aligning conveyor <NUM>, the second aligning conveyor <NUM>, and the third aligning conveyor <NUM> simultaneously perform a conveying operation in the same direction. For that reason, the N-number of the products G aligned in a line on the first aligning conveyor <NUM> and the second aligning conveyor <NUM> move in unison toward the third aligning conveyor <NUM> and advance on the third aligning conveyor <NUM>.

As shown in <FIG> and <FIG>, a conveyance direction downstream end 221b of the first aligning conveyor <NUM> and a conveyance direction upstream end 222a of the second aligning conveyor <NUM> oppose each other.

Here, the state in which the downstream end 221b of the first aligning conveyor <NUM> and the upstream end 222a of the second aligning conveyor <NUM> oppose each other is a state in which the downstream end 221b of the first aligning conveyor <NUM> and the upstream end 222a of the second aligning conveyor <NUM> are close enough to each other that the conveyance surface of the first aligning conveyor <NUM> and the conveyance surface of the second aligning conveyor <NUM> form a substantially continuous conveyance surface. This state is a first state.

In this first state, it is preferred that the gap between the downstream end 221b of the first aligning conveyor <NUM> and the upstream end 222a of the second aligning conveyor <NUM> be within <NUM>.

As shown in <FIG> and <FIG>, each time the first aligning conveyor <NUM> catches one product G, it repeats the operation of conveying that product G the fixed distance (pitch L) toward the second aligning conveyor <NUM>, and when the last product G comes onto the first aligning conveyor <NUM>, namely, when one line's worth of a group of products is reached, the first aligning conveyor <NUM> performs a conveying operation at a longer pitch than the fixed distance (pitch L) only at that time because the group of products G must be discharged from the first aligning conveyor <NUM>. At the same time, the second aligning conveyor <NUM> and the third aligning conveyor <NUM> also perform a conveying operation at the same speed.

<FIG> is a front view of the product aligning unit <NUM> after the aligned group of products G has completely transferred to the second aligning conveyor <NUM>. In <FIG>, just the first aligning conveyor <NUM>, upon ending the longer pitch conveying operation, decelerates, stops, and prepares to catch the next group of products G. At this time, the second aligning conveyor <NUM> and the third aligning conveyor <NUM> convey the group of products G handed over from the first aligning conveyor <NUM>.

In a case where the products G are small bag products and many of them can be placed on the first aligning conveyor <NUM>, or in a case where the conveyance speed is slow, the first state shown in <FIG>, <FIG> is employed as the posture of the second aligning conveyor <NUM>.

However, in a case where the products G are large bag products and the conveyance speed is fast to increase production capacity and the second aligning conveyor <NUM> and the third aligning conveyor <NUM> perform a conveying operation except for when the products are inserted, there is the concern that when the second aligning conveyor <NUM> is conveying a preceding group of products the product at the front of the subsequent group of products will come into contact with the second aligning conveyor <NUM> and be pulled onto the second aligning conveyor <NUM>.

Therefore, while the second aligning conveyor <NUM> is performing the conveying operation, the controller <NUM> switches the second aligning conveyor <NUM> to a second state, which is a state in which the position of the upstream end 222a of the second aligning conveyor <NUM> is lower than it is in the first state with respect to the downstream end 221b of the first aligning conveyor <NUM>.

<FIG>, and <FIG> are front views of the product aligning unit <NUM> when the second aligning conveyor <NUM> is in the second state. In <FIG>, and <FIG>, a product G on the conveyance surface of the first aligning conveyor <NUM> is shown moving closer to the second aligning conveyor <NUM>.

In <FIG>, and <FIG>, in the second state the upstream end 222a of the second aligning conveyor <NUM> is lowered in the direction of the arrow until the conveyance surface of the second aligning conveyor <NUM> is lower than the downstream end 221b of the first aligning conveyor <NUM>.

In control terms, the controller <NUM> lowers the upstream end 222a of the second aligning conveyor <NUM> after the last product G of the group of products G has moved from the conveyance surface of the first aligning conveyor <NUM> onto the conveyance surface of the second aligning conveyor <NUM>.

As shown in <FIG>, while the second aligning conveyor <NUM> is conveying a preceding group of products G, or even when a group of products G on the third aligning conveyor <NUM> is not yet standing up, the product G at the front of the subsequent group of products moves closer to the second aligning conveyor <NUM>.

However, because the upstream end 222a of the second aligning conveyor <NUM> has been lowered, the product at the front of the subsequent group of products does not come into contact with the second aligning conveyor <NUM> and is not pulled onto the second aligning conveyor <NUM>, and the line of accumulation of the group of products is also inhibited from becoming disarranged.

<FIG> is a front view of the product aligning unit <NUM> when the aligned group of products G has been switched to a standing state on the third aligning conveyor <NUM>. In <FIG>, a stand-up conveyor <NUM> whose conveyance surface moves in the vertical direction is disposed on the conveyance direction terminal end portion of the third aligning conveyor <NUM>. It will be noted that in <FIG> illustration of the stand-up conveyor <NUM> is omitted for convenience of description.

After the group of products G has moved from the second aligning conveyor <NUM> onto the third aligning conveyor <NUM>, the product G at the front stands up because of the conveyance surface of the stand-up conveyor <NUM> that moves in the vertical direction, and then the subsequent products G also stand up.

When the group of products G is in the standing state at the third aligning conveyor <NUM>, products G are not present on the conveyance surface of the second aligning conveyor <NUM>, and products G can be received from the first aligning conveyor <NUM>. Moreover, the timing is such that on the first aligning conveyor <NUM> the product at the front of the next group of products G has moved closer to and is about to drop onto the second aligning conveyor <NUM>. For that reason, the upstream end 222a of the second aligning conveyor <NUM> is raised so that the second aligning conveyor <NUM> switches to the first state and can support the product at the front of the group of products G.

The timing of this up/down operation of the second aligning conveyor <NUM> will be described in the section titled "(<NUM>) Control" in the latter part of this specification.

It will be noted that according to the invention, as shown in <FIG>, <FIG>, <FIG>, and <FIG>, in the first state the conveyance surfaces of the first aligning conveyor <NUM> and the second aligning conveyor <NUM> are both inclined. Additionally, as shown in <FIG>, and <FIG>, in the second state just the upstream end 222a of the second aligning conveyor <NUM> is lowered so that the conveyance surface of the second aligning conveyor <NUM> in the second state is substantially horizontal.

Furthermore, the controller <NUM> can decide whether or not to execute the switching to the second state depending on the size of the products G (e.g., the bag size) or can decide whether or not to execute the switching to the second state depending on the required production capacity.

The third aligning conveyor <NUM> conveys, in front of the openings of the cardboard boxes B standing by, the group of products G aligned by the first aligning conveyor <NUM> and the second aligning conveyor <NUM>. The third aligning conveyor <NUM> doubles as an element of the product inserting unit <NUM> described below.

The product inserting unit <NUM> sandwiches the front and rear of the group of products G aligned in a line by the third aligning conveyor <NUM> and inserts the whole group of products G into the cardboard boxes B. As shown in <FIG>, the product inserting unit <NUM> has the stand-up conveyor <NUM>, a push-toward plate <NUM>, and an insertion plate <NUM> in order to sandwich the aligned group of products G.

The stand-up conveyor <NUM> is provided over the downstream end of the third aligning conveyor <NUM> and blocks the advance of the products G forming a line and being conveyed thereto. The stand-up conveyor <NUM> is disposed in such a way that its conveyance surface is always orthogonal to the conveyance direction of the products G.

<FIG> is a front view of the region around the third aligning conveyor <NUM> just before the aligned group of products G is made to stand up. Furthermore, <FIG> is a front view of the region around the third aligning conveyor <NUM> in a state in which the aligned group of products G of <FIG> has been made to stand up. In <FIG> and <FIG>, the conveyance surface of the stand-up conveyor <NUM> moves vertically upward a little before the products G come into contact with the conveyance surface of the stand-up conveyor <NUM>. Then, when the leading end of the product G at the front comes into contact with the conveyance surface of the stand-up conveyor <NUM>, an upward force acts on the leading end of the product G, and the horizontal movement of the product G by the third aligning conveyor <NUM> also continues, so the product G at the front can reliably stand up.

The push-toward plate <NUM> pushes the product at the rear of the N-number of products G aligned in a line to thereby sandwich the products G between itself and the stand-up conveyor <NUM> and cause the products G to stand up.

The push-toward plate <NUM> is provided on the upstream end side of the third aligning conveyor <NUM>, but while the line of products G is moving from the second aligning conveyor <NUM> to the third aligning conveyor <NUM>, the push-toward plate <NUM> is accommodated on the side of the third aligning conveyor <NUM> so that its flat surface portion is parallel to the conveyance direction of the products G. Furthermore, when the product G at the rear of the line has completely transferred from the second aligning conveyor <NUM> to the third aligning conveyor <NUM>, the push-toward plate <NUM> swings so that its flat surface portion becomes orthogonal to the conveyance direction of the products G Moreover, the push-toward plate <NUM> pushes the product G at the rear of the line to thereby push the entire line toward the stand-up conveyor <NUM>.

At this time, the conveyance surface of the stand-up conveyor <NUM> is moving vertically upward, so the product G at the front of the line stands up along the conveyance surface of the stand-up conveyor <NUM>, and the next product G stands up along the product G at the front that has been made to stand up. The subsequent products G also successively stand up because of the same operation, so the N-number of products G become aligned in a standing state.

Furthermore, the product inserting unit <NUM> collectively pushes, via the insertion plate <NUM>, the N-number of products G in the standing state into the cardboard boxes B. The insertion plate <NUM> is positioned on the opposite side of the position of the cardboard boxes B across the third aligning conveyor <NUM>. When viewed from the second aligning conveyor <NUM> side, the open surfaces of the cardboard boxes B are positioned on the right side of the third aligning conveyor <NUM> and the insertion plate <NUM> is positioned on the left side of the third aligning conveyor <NUM>.

The insertion plate <NUM> stands by with its flat surface portion opposing the openings of the cardboard boxes B. After the N-number of products G have been switched to the standing state, the insertion plate <NUM> pushes the N-number of products G toward the open surfaces of the cardboard boxes B and in one fell swoop inserts the N-number of products G through the openings to the bottoms of the cardboard boxes B. The insertion plate <NUM> crosses between the stand-up conveyor <NUM> and the push-toward plate <NUM> and advances to the open surfaces of the cardboard boxes B.

The packing process P3 has the product receiving unit <NUM> that receives the products G into the cardboard boxes B, the second posture changing unit <NUM> that changes the posture of the cardboard boxes so that the openings of the cardboard boxes face up, and the case sealing unit <NUM> that conveys the cardboard boxes B that have finished being packed with the products G and at the same time closes the openings of the cardboard boxes B.

The product receiving unit <NUM> maintains the cardboard boxes B in the first posture and has the cardboard boxes B stand by with the openings of the cardboard boxes B opposing the insertion plate <NUM> of the product inserting unit <NUM>. The N-number of products G that have been switched to the standing state in the product inserting unit <NUM> are pushed out by the insertion plate <NUM> toward the open surfaces in the cardboard boxes B, so the product receiving unit <NUM> stands by in that position until the N-number of products G are completely inserted through the openings to the bottoms of the cardboard boxes B.

When a first layer of the N-number of products G is inserted into a cardboard box B, the product receiving unit <NUM> descends a predetermined distance. Then, in order to receive a second layer of the N-number of products G, the product receiving unit <NUM> has the cardboard box B stand by in such a way that the portion of the opening of the cardboard box B that leads to the space above the first layer opposes the insertion plate <NUM>.

The product receiving unit <NUM> repeats the above-described operation so that an i-th layer of the N-number of products G is inserted into the cardboard box B, and the receiving of the products into the cardboard box B is finished.

As shown in <FIG>, the second posture changing unit <NUM> has a posture changing mechanism <NUM> that changes the posture of the cardboard boxes B packed with the products G to a posture in which the openings face up.

The posture changing mechanism <NUM> rotates the cardboard boxes B so that the open surfaces that had been vertical until then become horizontal, namely, so that the open surfaces face up. The posture changing mechanism <NUM> uses an L-shaped member with suckers that simultaneously suck the side surface and the bottom surface of the cardboard boxes B to hold the cardboard boxes B, and when the L-shaped member rotates <NUM>°, the cardboard boxes B rotate.

When the cardboard boxes B have been rotated <NUM>° by the posture changing mechanism <NUM>, the cardboard boxes B are placed on the discharge conveyor <NUM> in a state in which the openings face up. The discharge conveyor <NUM> conveys the cardboard boxes B to the discharge position.

In the time until the cardboard boxes B are conveyed to the discharge position, the openings of the cardboard boxes B are closed as a result of the front flap Zfaa, the rear flap Zfab, the left flap Zfal, and the right flap Zfar being folded and are sealed by the tape applicator <NUM>. The tape applicator <NUM> is installed near the discharge position on the conveyance path of the cardboard boxes B, and taping is performed before the cardboard boxes B reach the discharge position.

<FIG> is a timing chart showing the operations of the first aligning conveyor <NUM>, the second aligning conveyor <NUM>, and the third aligning conveyor <NUM>. Below, the timing when the second aligning conveyor <NUM> is raised and lowered will be described with reference to <FIG> and <FIG>.

First, in <FIG> and <FIG>, the first aligning conveyor <NUM> performs an intermittent conveyance at pitch L each time each one of the first to the fourth products G of a first group of products lands on the first aligning conveyor <NUM>.

The second aligning conveyor <NUM> starts an intermittent operation at the same time as the third intermittent conveyance by the first aligning conveyor <NUM> when the third product G lands on the first aligning conveyor <NUM>.

This is because, as shown in <FIG>, the product G that landed first on the first aligning conveyor <NUM> is starting to move onto the upstream end 222a of the second aligning conveyor <NUM>, so by also causing the second aligning conveyor <NUM> to intermittently convey at pitch L at the same time, the product G is received onto the second aligning conveyor <NUM>.

Consequently, at the time in point when the fourth product G lands on the first aligning conveyor <NUM> and there are a fourth intermittent conveyance by the first aligning conveyor <NUM> and a second intermittent conveyance by the second aligning conveyor <NUM>, at least the product G at the front has moved onto the second aligning conveyor <NUM>, and the third and fourth products G are on the first aligning conveyor <NUM>.

Then, after the fifth product G lands on the first aligning conveyor <NUM>, the first aligning conveyor <NUM> conveys at pitch La, which is greater than pitch L. This is a conveyance amount needed to transfer to the second aligning conveyor <NUM> the third and fourth products G that have already landed on the first aligning conveyor <NUM> and the fifth product G that has just landed.

After ending the intermittent conveyance at pitch La, the first aligning conveyor <NUM> receives a second group of products G and starts the intermittent conveyance at pitch L.

The second aligning conveyor <NUM> starts an intermittent conveying operation at a long pitch Lb at the same time as when the first aligning conveyor <NUM> starts the intermittent conveyance at pitch La. The upstream end 222a of the second aligning conveyor <NUM> is lowered in the middle of this intermittent operation at the long pitch Lb and at the same time as when the first aligning conveyor <NUM> ends the intermittent conveyance at pitch La (see <FIG>).

The reason the upstream end 222a of the second aligning conveyor <NUM> is lowered in this way is, the first product G of the second group that has already landed on the first aligning conveyor <NUM> is moving closer to the upstream end 222a of the second aligning conveyor <NUM>, and if the upstream end 222a is not lowered the first product G of the second group will be pulled onto the second aligning conveyor <NUM> that is conveying the first group of products G.

Then, at the point in time when the second product G of the second group lands on the first aligning conveyor <NUM> and the intermittent conveyance at pitch L finishes, the first group of products G has been transferred from the second aligning conveyor <NUM> to the third aligning conveyor <NUM> and the first group of products G has been switched to the standing state by the stand-up conveyor <NUM> on the third aligning conveyor <NUM>, so there are no products G on the second aligning conveyor <NUM>, and the second aligning conveyor <NUM> can receive the second group of products G from the first aligning conveyor <NUM>. For that reason, the upstream end 222a of the second aligning conveyor <NUM> is raised and returned to its original position (see <FIG>).

It will be noted that the intermittent conveyance at the long pitch Lb by the second aligning conveyor <NUM> finishes by the time the second product G of the second group lands on the first aligning conveyor <NUM> and the intermittent conveyance at pitch L finishes and the third product G lands.

The third aligning conveyor <NUM> starts an intermittent conveying operation at a long pitch Lc at the same time as when the first aligning conveyor <NUM> starts the intermittent conveyance at pitch La. The third aligning conveyor <NUM> finishes the intermittent conveyance at the long pitch Lc by the time the third product G of the second group lands on the first aligning conveyor <NUM> and the intermittent conveyance at pitch L finishes and the fourth product G lands.

During the time period of the intermittent conveyance at the long pitch Lc, the first to fifth products G of the first group finish aligning on the conveyance surface of the third aligning conveyor <NUM>, and their insertion into the cardboard box B finishes.

(<NUM>-<NUM>)
In the second aligning conveyor <NUM> of the packing system <NUM>, the second state is a state in which the position of the upstream end 222a of the second aligning conveyor <NUM> is lower than it is in the first state with respect to the downstream end 221b of the first aligning conveyor <NUM>, so even if the package at the front of the next group of packages sticks out from the downstream end 221b of the first aligning conveyor <NUM>, it is kept from contacting the conveyance direction upstream end 222a of the second aligning conveyor <NUM> and is not pulled onto the second aligning conveyor <NUM>, and the line of accumulation is also inhibited from becoming disarranged.

(<NUM>-<NUM>)
In the first state the conveyance surface of the first aligning conveyor <NUM> and the conveyance surface of the second aligning conveyor <NUM> form a substantially continuous conveyance surface, and in the second state the conveyance surface of the second aligning conveyor <NUM> is lower than the downstream end 221b of the first aligning conveyor <NUM>. For that reason, in the second state the continuity between the downstream end 221b of the first aligning conveyor <NUM> and the upstream end 222a of the second aligning conveyor <NUM> is eliminated and the position of the upstream end 222a of the second aligning conveyor <NUM> is lower than it is in the first state, so even if the package at the front of the next group of packages sticks out from the downstream end 221b of the first aligning conveyor <NUM>, it is kept from contacting the conveyance direction upstream end 222a of the second aligning conveyor <NUM> and is not pulled onto the second aligning conveyor <NUM>, and the line of accumulation is also inhibited from becoming disarranged.

(<NUM>-<NUM>)
In the second state, due to the upstream end 222a of the second aligning conveyor <NUM> being lower, a package sticking out from the upstream end of the first aligning conveyor <NUM> does not contact the conveyance surface of the second aligning conveyor <NUM> as long as the center of gravity of the package remains on the conveyance surface of the first aligning conveyor <NUM>, so the package is not pulled onto the second aligning conveyor <NUM>, and the line of accumulation is also inhibited from becoming disarranged.

(<NUM>-<NUM>)
In the second aligning conveyor <NUM> of the packing system <NUM>, even when the second aligning conveyor <NUM> and the final conveyance position of the group of packages are located away from each other, the group of packages can be conveyed to the final conveyance position via the third aligning conveyor <NUM>.

(<NUM>-<NUM>)
The controller <NUM> causes the first aligning conveyor <NUM> to perform the accumulating operation by moving the conveyance surface by a predetermined amount (pitch L) each time the packages come onto the conveyance surface of the first aligning conveyor <NUM>, so the packages following after the package at the front of the group lie on top of each other in the same inclined state and align.

(<NUM>-<NUM>)
When the last package of the group of the packages comes onto the conveyance surface of the first aligning conveyor <NUM>, the controller <NUM> moves the conveyance surface by an amount greater than the predetermined amount and simultaneously causes the second aligning conveyor <NUM> to operate, so the last package of the group of the packages reliably moves from the conveyance surface of the first aligning conveyor <NUM> onto the conveyance surface of the second aligning conveyor <NUM>.

(<NUM>-<NUM>)
The controller <NUM> lowers the upstream end 222a of the second aligning conveyor <NUM> after the last package of the group of the packages moves from the conveyance surface of the first aligning conveyor <NUM> onto the conveyance surface of the second aligning conveyor <NUM>, so it is difficult for the line of the group to become disarranged.

(<NUM>-<NUM>)
In a case where the bag size is large, the package at the front of the next group sticks out from the downstream end 221b of the first aligning conveyor <NUM> and contacts and becomes pulled onto the second aligning conveyor <NUM> that is conveying the preceding group, so the controller <NUM> decides whether or not to execute the switching to the second state depending on the bag size of the packages.

Claim 1:
A package accumulating device that conveys plural bag packages to a predetermined position while performing an accumulating operation that aligns the packages (G) such that parts of each of the packages (G) lie on top of parts of adjacent packages (G) in a thickness direction, the package accumulating device comprising:
a first conveyor (<NUM>) that comprises a conveyance surface for accumulating the packages (G), the first conveyor (<NUM>) performing the accumulating operation with the conveyance surface;
a second conveyor (<NUM>) that comprises a conveyance surface, the second conveyor (<NUM>) receiving and further conveying a group of the packages aligned by the first conveyor (<NUM>) and being moved from the conveyance surface of the first conveyor onto the conveyance surface of the second conveyor; and
a control unit (<NUM>) that performs switching between a first state in which a downstream end (221b) of the first conveyor (<NUM>) in a conveyance direction and an upstream end (222a) of the second conveyor (<NUM>) in the conveyance direction oppose each other when the second conveyor (<NUM>) accepts the group of the packages from the first conveyor (<NUM>) and a second state in which a position of the upstream end (222a) of the second conveyor (<NUM>) is lower than it is in the first state with respect to the downstream end (221b) of the first conveyor (<NUM>), characterized in that
the control unit (<NUM>) lowers the upstream end (222a) of the second conveyor (<NUM>) after a last package of the group of the packages moves from the conveyance surface of the first conveyor (<NUM>) onto the conveyance surface of the second conveyor (<NUM>), and wherein
in the first state, the conveyance surfaces of the first conveyor (<NUM>) and the second conveyor (<NUM>) are both inclined, and
in the second state, the upstream end (222a) of the second conveyor (<NUM>) is lowered so that the conveyance surface of the second conveyor (<NUM>) becomes horizontal.