JP7777957B2 - Pallet transport device - Google Patents

Description

The present invention relates to a pallet transport device.

In the pallet supply device disclosed in Patent Document 1 below, empty pallets stored in a pallet magazine are sent out one by one by an output roller conveyor as needed and transported to a predetermined location. A height detector is installed along the way to detect nails or other objects protruding upward from the empty pallet. If a nail or other object protrudes upward from the empty pallet, the height detector's engagement plate comes into contact with the nail or object and swings in the transport direction. This swing is detected by a detector attached to the engagement plate's swing shaft.

Japanese Patent Application Publication No. 5-294433

For example, in a pallet transport device that transports pallets to a product placement position where products processed by automatic processing equipment are placed, the surrounding area is divided into a first area where workers work, and a second area where the automatic processing equipment is located. Within the first area, workers place the pallet on the pallet placement section of the pallet transport device. However, depending on the placement position of the pallet on the pallet placement section, the pallet may be transported outside the specified tolerance range and become stuck in the second area. In such cases, workers may have to reposition the stuck pallet in the second area.

A pallet conveying device according to one aspect of the present invention comprises a conveying section that extends along the conveying direction of a pallet having a rectangular shape in a plan view and is capable of conveying the pallet while maintaining the orientation of the pallet in the conveying direction; a partition wall section that is provided between the upstream and downstream sections of the conveying section in the conveying direction and that divides the conveying section and its surrounding area into a first area that includes the upstream section and a second area that includes the downstream section; a pallet placement section that is provided in the upstream section and is capable of placing the pallet; and a horizontal width direction of the pallet placement section that is perpendicular to the conveying direction. a widthwise positioning section having a pallet abutment section that can position the pallet in the width direction by abutting against an edge on one widthwise side of the pallet placed on the pallet placement section; and a regulating section that is disposed between the pallet placement section and the partition wall on the other widthwise side of the conveying section, wherein the pallet is allowed to pass through in the second region within a predetermined tolerance range in the width direction of the conveying section, and the pallet abutment section and the end on the one widthwise side of the regulating section are located inside the predetermined tolerance range in the width direction.

According to one aspect of this pallet conveying device, a pallet can be placed on the pallet placement section from at least the other widthwise side of the pallet placement section. The widthwise positioning section then allows the pallet to be positioned more reliably. Furthermore, if a pallet is positioned such that it will become stuck in the second area when transported, mechanical interference with the regulating section occurs during transport, preventing it from being transported downstream in the transport direction. This prevents the pallet from being transported to the second area.

One aspect of the present invention provides a pallet conveying device that can prevent pallets positioned in a way that would cause them to become stuck in the second area when conveyed from being conveyed to the second area.

FIG. 1 is a perspective view showing an example of the overall configuration of a pallet conveying device according to an embodiment. FIG. 2 is a plan view showing an example of the overall configuration of a pallet conveying device according to an embodiment. Figure 3 is a partial oblique view showing the vicinity of the pallet loading section of the pallet conveying device of the first embodiment, and is a diagram showing the arrangement relationship between the conveying section, the pallet loading section, the width direction positioning section, the conveying direction positioning section, and the regulating section. FIG. 4 is a partial plan view showing the vicinity of the pallet placement unit of the pallet transport device according to the first embodiment, and shows a state in which the pallet is positioned on the pallet placement unit. Figure 5 is a partial plan view showing the vicinity of the pallet loading section to explain the operational effect of the pallet conveying device of the first embodiment, and shows a state in which the transport of a pallet loaded on the pallet loading section in a misaligned state is restricted. Figure 6 is a partial oblique view showing the vicinity of the pallet loading section of the pallet conveying device of the second embodiment, and is a diagram showing the arrangement relationship between the conveying section, the pallet loading section, the width direction positioning section, the conveying direction positioning section, and the regulating section. FIG. 7 is a diagram showing a state in which the conveying direction positioning unit shown in FIG. 6 has been moved to the inside in the width direction of the conveying unit. FIG. 8 is a partial plan view showing the vicinity of the pallet placement unit of the pallet transport device according to the second embodiment, and shows a state in which the pallet is positioned on the pallet placement unit. Figure 9 is a partial plan view showing the vicinity of the pallet loading section to explain the operational effect of the pallet conveying device of the second embodiment, and shows a state in which the transport of a pallet placed on the pallet loading section in a misaligned state is restricted.

The pallet conveying device according to the embodiment will be described below with reference to the drawings. In each figure, FR and RR indicate the front and rear in the longitudinal direction of the pallet conveying device. LH and RH indicate the left and right in the width direction of the pallet conveying device. UP and DN indicate the top and bottom. In the following description, the front and rear in the longitudinal direction and the left and right in the width direction of the pallet conveying device will be referred to simply as "front," "rear," "left," and "right," respectively. Elements with the same function will be given the same symbols, and duplicate descriptions will be omitted.

In the following description, the "conveying direction" refers to the direction of the route along which the pallet 5 is transported. In the pallet transport devices 1 and 2 according to the embodiments, the rear direction corresponds to the conveying direction, as indicated by arrow D in Figure 1 or Figure 2. Similarly, in the examples shown in Figures 3 to 9, the rear direction corresponds to the conveying direction. Furthermore, the "width direction" refers to the horizontal direction perpendicular to the conveying direction. In the examples shown in Figures 1 to 9, the left-right direction corresponds to the width direction.

Figure 1 is a perspective view showing an example of the overall configuration of a pallet conveying device 1 according to an embodiment. Figure 2 is a plan view showing an example of the overall configuration of a pallet conveying device 1 according to an embodiment. The pallet conveying device 1 is a device that conveys a pallet 5 to, for example, a product placement position 4. The pallet conveying device 1 comprises a conveying section 10, a pallet placement section 20, and a partition wall section 30. As in the illustrated example, the pallet conveying device 1 may also comprise a first device 40.

An automatic processing device (not shown) is located behind the pallet conveying device 1 illustrated in Figure 1 or Figure 2. The product placement position 4 is where the product 3 processed by the automatic processing device is placed. The automatic processing device processes the workpiece and manufactures the product 3 without manual operation by an operator.

The automatic processing device may be, for example, a bending device that bends a plate-shaped workpiece. The product 3 is placed on a pallet 5 placed at a product placement position 4, for example, by a robot arm of an industrial robot provided in the automatic processing device.

As shown in the example, the pallet 5 is a loading platform made of, for example, resin, that has a roughly rectangular shape in a plan view. Furthermore, the dimensions of each side of the pallet 5 in a plan view are greater than the vertical dimension. Therefore, the pallet 5 has a flat, box-like shape overall. The upper surface of the pallet 5 is roughly flat, on which the product 3 can be placed. The lower surface of the pallet 5 is also roughly flat. Pallets 5 can be stacked vertically.

The conveying unit 10 extends along the conveying direction of the pallet 5. The conveying unit 10 is configured to be able to convey the pallet 5 while maintaining the orientation of the pallet 5 in the conveying direction. The conveying unit 10 illustrated in the figure is able to convey the pallet 5 placed on the conveying unit 10 towards the first device 40. The conveying unit 10 extends approximately horizontally in the front-to-rear direction. Therefore, the pallet 5 on the conveying unit 10 is conveyed on an approximately horizontal plane. Note that although the conveying unit 10 illustrated in the figure extends linearly in the front-to-rear direction, this is not limiting. The conveying unit 10 may include a portion that curves, for example, to the left or right.

As illustrated in the figure, the conveying unit 10 may include a pair of conveying units 10a and 10b that are spaced apart in the width direction of the conveying unit 10 and extend parallel to each other. The conveying units 10a and 10b constitute both ends of the conveying unit 10 in the width direction. The conveying units 10a and 10b each include a drive roller 11 that can be driven and controlled by a control circuit (not shown).

The drive roller 11 has a cylindrical shape extending in the width direction of the conveying section 10 and may be made of metal such as iron or steel. The drive roller 11 contains an electric motor (not shown) whose drive can be controlled by a control circuit. Therefore, the drive roller 11 can rotate around a central axis parallel to its extension direction.

Each of the conveying units 10a and 10b has a plurality of drive rollers 11 installed at predetermined intervals in the extension direction of the conveying unit 10. Cover units 12 may be attached between the plurality of drive rollers 11. The cover units 12 are plate-like members having a substantially rectangular shape in a plan view, and form at least a portion of the upper side of the conveying unit 10. The upper surface of the cover unit 12 is located below the uppermost portion of the outer circumferential surface of the drive roller 11.

By driving the drive rollers 11, the pallet 5 placed on the conveying unit 10 can be conveyed. For example, by rotating the multiple drive rollers 11 installed on each of the conveying units 10a and 10b clockwise as viewed from the right, the pallet 5 on the conveying unit 10 can be conveyed backward. At this time, each of the multiple drive rollers 11 installed on each of the conveying units 10a and 10b rotates, for example, by approximately the same amount of rotation. Therefore, the orientation of the pallet 5 in the conveying direction is maintained during the process of conveying the pallet 5 placed on the conveying unit 10.

Note that "the orientation relative to the conveying direction is maintained" means that there is no relative change in the angle formed by each side of the outer periphery of the pallet 5 relative to the conveying direction, or in the widthwise position on the conveying unit 10, as the pallet 5 is conveyed. This also includes cases where the relative change in the angle and widthwise position is maintained within a predetermined tolerance range. In the example shown, as the pallet 5 is conveyed backward, the pallet 5 does not rotate horizontally relative to the conveying unit 10, and its relative widthwise position on the conveying unit 10 does not change. Note that the amount of rotation of each of the drive rollers 11 installed on each of the conveying units 10a and 10b may be set as appropriate so that the orientation of the pallet 5 is maintained relative to the conveying direction.

A pallet placement unit 20 is arranged in the upstream section 13 of the conveying section 10 in the conveying direction. A pallet 5 can be placed on the pallet placement unit 20. In the example shown, the pallet placement unit 20 is arranged at the upstream end of the upstream section 13 in the conveying direction. Furthermore, four pallets 5 are stacked vertically in four layers on the pallet placement unit 20, but this is not limited to this. A single pallet 5 may also be placed on the pallet placement unit 20.

The upstream section 13 is a region of the conveying section 10 that extends over a predetermined range upstream in the conveying direction. The upstream side in the conveying direction refers to the upstream side in the direction in which the pallet 5 is conveyed, in a direction parallel to the extension of the conveying section 10. In the example shown, the upstream side in the conveying direction is the front side. The downstream section 14 is a region of the conveying section 10 that extends over a predetermined range downstream in the conveying direction. The downstream side in the conveying direction refers to the downstream side in the direction in which the pallet 5 is conveyed, in a direction parallel to the extension of the conveying section 10. In the example shown, the downstream side in the conveying direction is the rear side.

An intermediate section 21 may be provided in the downstream section 14. The intermediate section 21 is an area where pallets 5 transported from the pallet loading section 20 can be temporarily placed before being transported into the first device 40. As illustrated in the figure, the intermediate section 21 may include loading positions 22a and 22b as positions where pallets 5 can be placed. Pallets 5 are placed in four vertically stacked layers at each of loading positions 22a and 22b. However, each of loading positions 22a and 22b may only have one pallet 5 placed thereat. By providing the intermediate section 21, more pallets 5 can be placed in the conveying section 10. The dimensions of the intermediate section 21 in the conveying direction can be set appropriately depending on the dimensions of the conveying section 10 in the conveying direction.

The partition wall 30 is provided between the upstream section 13 and downstream section 14 in the conveying direction of the conveying section 10. The partition wall 30 also divides the conveying section 10 and its surrounding area into a first region 90 that includes the upstream section 13 and a second region 91 that includes the downstream section 14.

The first area 90 is an area extending forward from the partition wall section 30. The first area 90 is an area where work related to the pallet conveying device 1 can be performed. For example, an operator can place a pallet 5 on the pallet placement section 20. The second area 91 is an area extending rearward from the partition wall section 30. The second area 91 is an area where automatic processing equipment and the first device 40 are located. The partition wall section 30 may include a fence section 31 and an object detection area 32.

The fence section 31 is a wall erected in the peripheral area of the pallet conveying device 1, extending from the left to the right of the pallet conveying device 1. The fence section 31 may be constructed, for example, by attaching mesh or lattice panels to an aluminum frame. A partition opening 33 penetrating in the front-to-rear direction is provided within a predetermined range of the fence section 31. The conveying section 10 extends from the first area 90 to the second area 91 through the partition opening 33. The fence section 31 mechanically divides the conveying section 10 and its peripheral area into the first area 90 and the second area 91.

The object detection area 32 is formed, for example, by an object detection unit (not shown) provided in the partition opening 33. The object detection unit may be a light curtain equipped with a light-emitting unit provided on one side of the partition opening 33 in the left-right direction and a light-receiving unit provided on the other side. The object detection area 32 is formed between the light-emitting unit and the light-receiving unit by receiving multiple parallel optical axes emitted by the light-emitting unit. The object detection area 32 optically divides the transport section 10 and its surrounding area into a first area 90 and a second area 91.

If at least some of the multiple optical axes emitted from the light-emitting unit are not received by the light-receiving unit, the control circuit determines that an object has entered the partition opening 33 and, for example, stops the transport of pallets 5 by the pallet transport device 1 and the automatic processing device.

Because the pallet conveying device 1 is equipped with the partition wall portion 30, workers are prevented from entering the second area 91 from the first area 90. Furthermore, even if part of a worker's body enters the partition opening 33, for example, the conveyance of pallets 5 by the pallet conveying device 1 and the automatic processing equipment can be temporarily stopped.

The first device 40 is disposed downstream of the conveying unit 10 in the conveying direction. The first device 40 has an inlet 41 through which pallets 5 conveyed from the conveying unit 10 are brought in. The inlet 41 is connected to the end of the conveying unit 10 on the downstream side in the conveying direction. The conveying unit 10 conveys the pallets 5 while maintaining their orientation in the conveying direction, so the pallets 5 are brought into the inlet 41 in the orientation they had when they passed through the partition wall unit 30. In this way, the first device 40 has an inlet 41 connected to the downstream unit 14 through which the pallets 5 are brought in in the orientation they had when they passed through the partition wall unit 30. The inlet 41 also has a substantially rectangular shape when viewed from the front to back.

In the illustrated example, the first device 40 is a pallet lifting device 46. The pallet lifting device 46 is a device that supplies the lowest pallet 5 of multiple pallets 5 stacked vertically and stored in an internal space 47 to the product loading position 4. The internal space 47 is a space that can accommodate a pallet 5 carried in through the carry-in entrance 41. The internal space 47 has a roughly rectangular shape in a plan view.

The pallet lifting device 46 has a rear wall 42, a side wall 43a, and a side wall 43b. The rear wall 42 is a wall that defines the rear side of the internal space 47. The side wall 43a is a wall that defines the left side of the internal space 47. The side wall 43b is a wall that defines the right side of the internal space 47. The lower part of the internal space 47 is defined by the bottom (not shown) of the pallet lifting device 46. At least a portion of the bottom of the pallet lifting device 46 may be formed by the drive roller 11. In the illustrated example, the rear wall 42 has a substantially rectangular shape when viewed in the axial direction parallel to the front-to-rear direction. The side walls 43a and 43b have a substantially rectangular shape when viewed in the axial direction parallel to the left-to-right direction.

The front end 44a of the side wall 43a defines the widthwise end 41a of the inlet 41. The front end 44a is the upstream end of the side wall 43a in the conveying direction. The front end 44b of the side wall 43b defines the widthwise end 41b of the inlet 41. The front end 44b is the upstream end of the side wall 43b in the conveying direction.

A tapered surface 45a may be formed on the front end 44a. The tapered surface 45a is a wall surface that extends obliquely relative to the front-to-rear direction in a plan view. Furthermore, the upstream edge of the tapered surface 45a in the conveying direction is located further outward in the width direction of the inlet 41 than the downstream edge in the conveying direction.

A tapered surface 45b may be formed on the front end 44b. The tapered surface 45b is a wall surface that extends obliquely relative to the front-to-rear direction in a plan view. Furthermore, the upstream edge of the tapered surface 45b in the conveying direction is located further outward in the width direction of the inlet 41 than the downstream edge in the conveying direction.

When tapered surfaces 45a and 45b are formed, the left end 41a of the inlet 41 is defined by the upstream edge of tapered surface 45a in the conveying direction. Furthermore, the right end 41b of the inlet 41 is defined by the upstream edge of tapered surface 45b in the conveying direction. Therefore, the width dimension of the inlet 41 is configured to be larger than the width dimension of the internal space 47.

If the tapered surfaces 45a and 45b are not formed, the end 41a of the loading entrance 41 is defined by the widthwise inner edge of the front end 44a. Furthermore, the end 41b of the loading entrance 41 is defined by the widthwise inner edge of the front end 44b.

The shape, dimensions, etc. of the conveying unit 10 or the first device 40 are not limited to the example shown in the figure. The shape, dimensions, etc. of the conveying unit 10 or the first device 40 can be set appropriately depending on, for example, the shape, dimensions, and number of stacked tiers of the pallet 5. The first device 40 is not limited to the pallet lifting device 46. For example, it may be a pallet supply device that supplies one pallet 5 carried in through the carry-in entrance 41 to the product placement position 4.

Next, the pallet conveying devices 1 and 2 according to the embodiment will be described in more detail with reference to Figures 3 to 9. In the illustrated examples, one widthwise side of the pallet placement unit 20, pallet 5, conveying unit 10, or regulating units 70a and 70b corresponds to the left side. The other widthwise side of the pallet placement unit 20, pallet 5, conveying unit 10, or regulating units 70a and 70b corresponds to the right side. In the examples shown in Figures 3 to 5, one conveying direction side of the pallet placement unit 20 or pallet 5 corresponds to the front side. The other conveying direction side of the pallet placement unit 20 or pallet 5 corresponds to the rear side. In the examples shown in Figures 6 to 9, one conveying direction side of the pallet placement unit 20 or pallet 5 corresponds to the rear side. The other conveying direction side of the pallet placement unit 20 or pallet 5 corresponds to the front side.

(First embodiment)
3 or 4, the pallet transport device 1 according to the first embodiment includes a width direction positioning unit 50 and a restricting unit 70a. The pallet transport device 1 may also include a transport direction positioning unit 60a.

Figure 3 is a partial perspective view showing the vicinity of the pallet placement unit 20 of the pallet conveying device 1 according to the first embodiment, and is a diagram showing the relative positions of the conveying unit 10, pallet placement unit 20, width direction positioning unit 50, conveying direction positioning unit 60a, and regulating unit 70a. Figure 4 is a partial plan view showing the vicinity of the pallet placement unit 20 of the pallet conveying device 1 according to the first embodiment, and is a diagram showing the state in which the pallet 5 is positioned on the pallet placement unit 20.

The widthwise positioning unit 50 is disposed on one horizontal widthwise side of the pallet placement unit 20, perpendicular to the conveying direction. The widthwise positioning unit 50 also has a pallet abutment unit 51 that can abut against the edge 6a on one widthwise side of the pallet 5 placed on the pallet placement unit 20, thereby positioning the pallet 5 in the widthwise direction.

The widthwise positioning unit 50 illustrated in the figure is erected on the left side of the pallet placement unit 20. The widthwise positioning unit 50 may have, for example, an inverted C shape in plan view and may be made of metal such as iron or steel. The widthwise positioning unit 50 may be fixed to a fixture such as a bracket using a fastener such as a bolt.

The pallet abutment portion 51 may be configured with a pallet abutment surface 52. The pallet abutment surface 52 is a generally flat surface that forms the right side of the widthwise positioning portion 50. The pallet abutment surface 52 extends in the front-to-rear direction and has a generally rectangular shape when viewed in the axial direction parallel to the left-to-right direction. By configuring the pallet abutment portion 51 with the pallet abutment surface 52, the pallet 5 can be more reliably positioned in the widthwise direction in the positioning process described below.

The dimensions of the pallet abutment surface 52 in the front-to-rear direction are not limited to the example shown in the figure, and can be set appropriately depending on, for example, the dimensions of the pallet 5, the dimensions of the conveying section 10, the dimensions of the pallet conveying device 1, etc. Furthermore, the pallet abutment surface 52 is not limited to being the component that constitutes the pallet abutment portion 51. For example, the pallet abutment portion 51 may be constituted by arranging multiple rod-shaped members, such as cylindrical or rectangular pillar-shaped members, that extend in the vertical direction in the front-to-rear direction.

The conveying direction positioning unit 60a is arranged on one side of the pallet placement unit 20 in the conveying direction. Furthermore, the conveying direction positioning unit 60a can position the pallet 5 in the conveying direction by abutting the edge 6b on one side of the conveying direction of the pallet 5 placed on the pallet placement unit 20.

In the illustrated example, the transport direction positioning unit 60a extends in the width direction of the transport unit 10, on the front and left side of the pallet loading unit 20. The transport direction positioning unit 60a has a generally rectangular shape when viewed in the axial direction parallel to the front-to-rear direction, and may be made of a metal such as iron or steel. In addition, the left end of the transport direction positioning unit 60a may extend rearward and be connected to the front end of the width direction positioning unit 50.

A pallet abutment portion 61 is formed on the rear side of the conveying direction positioning portion 60a. This abutment portion 61 can position the pallet 5 in the conveying direction by abutting the edge 6b of the pallet 5 placed on the pallet placement portion 20. The pallet abutment portion 61 may be configured with a pallet abutment surface 62. The pallet abutment surface 62 is a flat surface extending in the left-right direction.

The regulating unit 70a is disposed between the pallet placement unit 20 and the partition wall unit 30 on the other widthwise side of the conveying unit 10. In the illustrated example, the regulating unit 70a is erected on the right side of the conveying unit 10, in an area rearward of the pallet placement unit 20 and forward of the partition wall unit 30. The regulating unit 70a may be a columnar unit with a generally C-shaped cross section that extends vertically. The regulating unit 70a may be made of a metal such as iron or steel, and may be fixed to a fixture such as a bracket using a fastener such as a bolt.

As shown in Figure 4, the pallet abutment portion 51 and the end portion 71a on one widthwise side of the regulating portion 70a are located inside the specified tolerance range 92 in the width direction of the conveying unit 10. Therefore, the widthwise distance L2 between the pallet abutment surface 52 and the end portion 71a is smaller than the widthwise dimension L5 of the specified tolerance range 92.

The predetermined tolerance range 92 refers to a predetermined range in the width direction of the conveying unit 10 through which the pallet 5 is allowed to pass when being conveyed from the first region 90 to the second region 91. The width dimension L5 of the predetermined tolerance range 92 is set so that the pallet 5 that has passed within the predetermined tolerance range 92 does not become stuck in the second region 91. Therefore, in the second region 91, the pallet 5 is allowed to pass within the predetermined tolerance range 92 in the width direction of the conveying unit 10.

The value of dimension L5 may be set based on the positions of devices and components provided in the conveying section 10 in the second region 91. For example, it may be determined based on the widthwise distance L3 (see Figure 2) between the ends 41a and 41b of the entrance 41. In some embodiments, the value of dimension L5 may be equal to or less than distance L3.

When viewed in the axial direction parallel to the width direction of the conveying unit 10, the pallet abutment portion 51 and the end portion 71a on one width direction side of the regulating portion 70a may at least partially overlap. The end portion 71a may be a plane extending in a direction parallel to the conveying direction. In the example shown, the rear end portion of the pallet abutment surface 52 and the front end portion of the end portion 71a overlap when viewed in the axial direction parallel to the left-right direction.

As illustrated in the figure, a pallet 5 can be placed and positioned on the pallet placement section 20. The state in which the pallet 5 is positioned on the pallet placement section 20 is simply referred to as the "positioned state." In the example shown, the edge 6a on one side of the pallet 5 in the width direction abuts against the pallet abutment surface 52. Furthermore, the edge 6b on one side of the pallet 5 in the conveying direction abuts against the pallet abutment surface 62. Therefore, the pallet 5 is positioned in the width direction and conveying direction on the pallet placement section 20.

The shape and dimensions of the pallet 5 are not limited to the example shown in the figure. The widthwise dimension L1 of the pallet 5 only needs to be smaller than the distance L2. In the example shown, the edge 6c on the other widthwise side of the pallet 5 is located inside the end 71a of the restricting portion 70a in the widthwise direction.

Next, with reference to Figure 2, the relative positions of the entrance 41, widthwise positioning unit 50, and restricting unit 70a will be explained.

The end 41a on one widthwise side of the loading entrance 41 is located widthwise outside the pallet abutment portion 51 of the widthwise positioning portion 50. The end 41b on the other widthwise side of the loading entrance 41 is located widthwise outside the end 71a on one widthwise side of the restricting portion 70a. The one widthwise side of the loading entrance 41 corresponds to the left side. The other widthwise side of the loading entrance 41 corresponds to the right side.

As illustrated in the figure, imaginary surface 80a, formed by virtually extending parallel to the conveying direction from the pallet abutment surface 52 toward the carry-in entrance 41, intersects with the opening surface of the carry-in entrance 41 widthwise inward of end 41a of the carry-in entrance 41. Furthermore, imaginary surface 80b, formed by virtually extending parallel to the conveying direction from end 71a toward the carry-in entrance 41, intersects with the opening surface of the carry-in entrance 41 widthwise inward of end 41b of the carry-in entrance 41. Therefore, distance L3 is greater than distance L2. The opening surface of the carry-in entrance 41 is a surface defined by the inner peripheral edge of the carry-in entrance 41.

Second Embodiment
Similar to the pallet conveying device 1, the pallet conveying device 2 according to the second embodiment includes a conveying section 10, a pallet placement section 20, and a partition wall section 30. The pallet conveying device 2 may also include a first device 40. As shown in FIGS. 6 to 8, the pallet conveying device 2 includes a width direction positioning section 50 and a regulating section 70b. The pallet conveying device 2 may also include a conveying direction positioning section 60b. In the following description of the second embodiment, only the configurations that differ from the preceding embodiments and variants (hereinafter referred to as the preceding embodiments, etc.) will be described. Elements that have the same functions as elements already described in the preceding embodiments, etc., will be designated by the same reference numerals, and their description will be omitted.

Figure 6 is a partial perspective view showing the vicinity of the pallet placement unit 20 of the pallet conveying device 2 according to the second embodiment, and illustrates the relative positions of the conveying unit 10, pallet placement unit 20, widthwise positioning unit 50, conveying direction positioning unit 60b, and regulating unit 70b. Figure 7 illustrates the conveying direction positioning unit 60b in Figure 6 after being moved to the inside in the width direction of the conveying unit 10. Figure 8 is a partial plan view showing the vicinity of the pallet placement unit 20 of the pallet conveying device 2 according to the second embodiment, illustrating the state in which a pallet 5 is positioned on the pallet placement unit 20.

The regulating portion 70b is disposed between the pallet placement portion 20 and the partition wall portion 30 on the other widthwise side of the conveying portion 10. In the illustrated example, the regulating portion 70b is erected in an area on the right side of the conveying portion 10, rearward of the pallet placement portion 20 and forward of the partition wall portion 30. The regulating portion 70b may be a columnar member extending in the vertical direction. The regulating portion 70b may be made of metal such as iron or steel, and may be fixed to a fixture such as a bracket using a fastener such as a bolt. Note that the end portion 71b on one widthwise side of the regulating portion 70b may be a flat surface extending in a direction parallel to the conveying direction.

The restricting portion 70b may include a conveying direction positioning portion 60b. In the illustrated example, the end portion 71b is configured by the conveying direction positioning portion 60b. The conveying direction positioning portion 60b has a substantially rectangular shape when viewed in the axial direction parallel to the left-right direction.

Extending portions 72a and 72b extend from the right side of the transport direction positioning portion 60b. Extending portions 72a and 72b are columnar portions extending in the left-right direction and may have a cylindrical shape, for example. The right ends of extending portions 72a and 72b are connected to each other by a gripping portion 73 extending in the up-down direction.

The extensions 72a and 72b are slidably supported by the support portion 74. The support portion 74 has a plate-like shape extending in the vertical direction, and a pair of openings (not shown) penetrating in the left-right direction are formed in each of the upper and lower regions. The extensions 72a and 72b are slidably inserted into each of the pair of openings. Therefore, the transport direction positioning portion 60b is supported by the support portion 74 so that it can slide left-right. Therefore, for example, an operator can grasp the grip portion 73 and move the transport direction positioning portion 60b toward the inside of the width direction of the transport unit 10, as shown by arrow B in Figure 7. In other words, the transport direction positioning portion 60b is disposed between the pallet placement portion 20 and the partition wall portion 30 so that it can move in the width direction of the transport unit 10.

In this way, the conveying direction positioning unit 60b is included in the regulating unit 70b. Therefore, the conveying direction positioning unit 60b is arranged on one conveying direction side of the pallet loading unit 20. In the example shown, the conveying direction positioning unit 60b is arranged on the rear side of the pallet loading unit 20. Furthermore, the conveying direction positioning unit 60b can position the pallet 5 in the conveying direction by abutting the edge 6d on one conveying direction side of the pallet 5 loaded on the pallet loading unit 20.

The conveying direction positioning unit 60b may include a pallet abutment portion 63 that forms its front end. In the example shown, the pallet abutment portion 63 is composed of a pallet abutment surface 64, which is a flat surface extending in the vertical direction.

When viewed in the axial direction parallel to the width direction of the conveying unit 10, the pallet abutment portion 51 and the end portion 71b on one width direction side of the regulating portion 70b may at least partially overlap. In the example shown, the rear end portion of the pallet abutment surface 52 and the end portion 71b overlap when viewed in the axial direction parallel to the left-right direction.

As shown in Figure 8, when the transport direction positioning unit 60b is moved toward the inside of the width direction of the conveying unit 10, the pallet 5 can be positioned on the pallet loading unit 20. In the example shown, the edge 6a of the pallet 5 abuts against the pallet abutment surface 52. Furthermore, the edge 6d of the pallet 5 abuts against the pallet abutment surface 64. Therefore, the pallet 5 is positioned in the width direction and transport direction on the pallet loading unit 20.

Note that end 71b of regulating portion 70b corresponds to end 71a of regulating portion 70a. Therefore, as shown in FIG. 9, the pallet abutment portion 51 and end 71b on one widthwise side of regulating portion 70b are located inside the specified tolerance range 92 in the width direction of the conveying section 10. Therefore, the widthwise distance L4 between the pallet abutment surface 52 and end 71b is smaller than dimension L5. Furthermore, end 41b on the other widthwise side of the inlet 41 is located widthwise outside end 71b on one widthwise side of regulating portion 70b. Therefore, distance L3 (see FIG. 2) is greater than distance L4.

In the illustrated example, the regulating unit 70b includes the conveying direction positioning unit 60b, but this is not limited to this. For example, the conveying direction positioning unit 60b may be disposed between the pallet placement unit 20 and the partition wall unit 30, separate from the regulating unit 70b, so as to be movable in the width direction of the conveying unit 10.

Next, an example of the operation of the pallet conveying device 1 according to the embodiment will be described with reference to Figure 1 or Figure 2.

First, a worker performs the pallet placement process in the first area 90. The pallet placement process is a process of placing a pallet 5 on the pallet placement section 20. In the illustrated example, the pallet 5 can be placed on the pallet placement section 20 from the right or front. The pallet placement process may be performed by a worker.

When loading multiple pallets 5, the pallets 5 may be stacked one by one on the pallet loading section 20. Alternatively, multiple pallets 5 may be stacked vertically in multiple layers and loaded onto the pallet loading section 20. The pallet loading process may also be carried out using a pallet truck, forklift truck, etc. A pallet truck is a transport vehicle equipped with the function of supporting cargo so that it can be raised and lowered. A forklift truck is a cargo handling vehicle equipped with the function of supporting cargo so that it can be raised and lowered.

Next, a positioning process is carried out to position the pallet 5. In the positioning process, first, for example, an operator presses the pallet 5 on the pallet mounting section 20 against the width direction positioning section 50 from the right. This brings the edge 6a of the pallet 5 into contact with the pallet contact surface 52. In the example shown in Figure 4, the edge 6a and the pallet contact surface 52 are in line contact in a plan view. Next, the pallet 5 is pressed from the rear against the transport direction positioning section 60a. This brings the edge 6b of the pallet 5 into contact with the pallet contact surface 62. In the example shown, the edge 6b and the pallet contact surface 62 are in line contact in a plan view. Through this positioning process, the pallet 5 is positioned.

Next, a transport process is performed to transport the pallet 5 placed on the pallet placement section 20. The transport process may be started by an operator operating the operation section 8 installed in the first area 90. During the transport process, the pallet 5 placed on the pallet placement section 20 passes between the widthwise positioning section 50 and the restriction section 70a and is transported toward the second area 91. Note that detection of objects passing through the partition opening 33 by the object detection section is suspended for a predetermined time until the pallet 5 passes through the partition opening 33 and is transported into the second area 91. After the pallet 5 passes through the partition opening 33 and is transported into the second area 91, object detection by the object detection section is resumed.

The pallet 5 transported into the second area 91 is transported through the intermediate section 21 into the inlet 41 of the pallet lifting device 46 and placed in the internal space 47. The pallet 5 placed in the internal space 47 is supplied to the product loading position 4 as appropriate. In the example shown in Figures 1 and 2, the pallet 5 is supplied to the product loading position 4 on the left side by a cylinder (not shown) attached to the bottom of the pallet lifting device 46. The cylinder may be a hydraulic cylinder or pneumatic cylinder that can extend and retract in the left-right direction. When the pallet 5 is transported into the internal space 47, the pallet 5 may be transported so that the edge 6d is pressed against the rear wall 42. This allows the pallet 5 to be more reliably positioned in the transport direction within the internal space 47.

If the first device 40 has a tapered surface 45a or a tapered surface 45b, the pallet 5 can be more reliably transported into the first device 40. For example, in the example shown in Figure 2, even if the edge 6c of the pallet 5 comes into contact with the tapered surface 45b, the pallet 5 can be guided into the internal space 47 along the tapered surface 45b.

When performing the positioning process using the pallet conveying device 2 according to the second embodiment, as shown in FIG. 8, the conveying direction positioning unit 60b is moved inward in the width direction of the conveying unit 10. Then, the pallet 5 on the pallet loading unit 20 is pressed against the width direction positioning unit 50 from the right. This causes the edge 6a of the pallet 5 to come into contact with the pallet contact surface 52. In the example shown, the edge 6a and the pallet contact surface 52 are in line contact in a plan view. Next, the pallet 5 is pressed against the conveying direction positioning unit 60b from the front. This causes the edge 6d of the pallet 5 to come into contact with the pallet contact surface 64. In the example shown, the edge 6d and the pallet contact surface 64 are in line contact in a plan view. This positioning process allows the pallet 5 to be positioned. Then, the conveying direction positioning unit 60b is moved outward in the width direction of the conveying unit 10. This allows the pallet 5 to pass between the pallet contact surface 52 and the regulating unit 70b during the conveying process.

Next, the effects of the pallet conveying device 1 according to the first embodiment will be described. In the following description, "misaligned state" refers to a state in which the pallet 5 is positioned such that it will become stuck in the second region 91 when conveyed. For example, if a pallet 5 placed in a misaligned state is conveyed from the first region 90 to the second region 91 on the conveying section 10 with a portion outside the predetermined tolerance range 92, there is a risk of mechanical interference with the ends 41a, 41b of the carry-in entrance 41. Such interference could cause the pallet 5a to become stuck in the carry-in entrance 41.

Figure 5 is a partial plan view showing the vicinity of the pallet placement section 20 to explain the operational effects of the pallet conveying device 1 according to the first embodiment, and shows a state in which the conveyance of a pallet 5a placed on the pallet placement section 20 in a misaligned state is restricted.

In the misaligned state illustrated in the figure, the pallet outer end 7 is located widthwise further outward than the end 71a of the restricting portion 70a. The pallet outer end 7 is the outermost portion of the edge 6c on the other widthwise side of the pallet 5 placed on the pallet placement section 20.

The pallet 5a shown in the figure is a pallet 5 that has been placed in a misaligned state. The rear corner of the edge 6a is in contact with the pallet contact surface 52. The pallet 5a is placed so that the edge 6a intersects the conveying direction at an angle in a plan view. Therefore, the pallet outer edge 7 is located to the right of the edge 71a. In the example shown, the pallet outer edge 7 is the corner of the edge 6c that is located furthest forward.

During the conveying process, the pallet 5a is conveyed in the direction of arrow A shown in the figure. At this time, the pallet 5a comes into contact with the regulating portion 70a. In the example shown, the edge 6c comes into contact with the end portion 71a. Because of this mechanical interference between the pallet 5a and the regulating portion 70a, the drive roller 11 in contact with the bottom surface of the pallet 5a rotates freely. This prevents the pallet 5a from being conveyed to the second region 91.

Next, we will explain the effects of the pallet conveying device 2 according to the second embodiment.

Figure 9 is a partial plan view showing the vicinity of the pallet placement section 20 to explain the operational effects of the pallet conveying device 2 according to the second embodiment, and shows a state in which the conveyance of a pallet 5a placed on the pallet placement section 20 in a misaligned state is restricted.

The rear corner of the edge 6a of the pallet 5a shown in the figure abuts against the pallet abutment surface 52. Furthermore, the pallet 5a is placed with the edge 6a diagonally intersecting the conveying direction in a plan view. Therefore, the outer edge 7 of the pallet is located to the right of the edge 71b.

During the conveying process, the pallet 5a is conveyed in the direction of arrow C shown in the figure. At this time, the pallet 5a comes into contact with the regulating portion 70b. In the example shown, the edge 6c comes into contact with the end 71b of the regulating portion 70b. Because of this mechanical interference between the pallet 5a and the regulating portion 70b, the drive roller 11 in contact with the bottom surface of the pallet 5a rotates freely. This prevents the pallet 5a from being conveyed to the second region 91.

The pallet conveying devices 1 and 2 may be configured to detect when the transport of a pallet 5a is restricted. For example, if a pallet 5 is not detected at a predetermined position in the second area 91 for a predetermined period of time, the control circuit may determine that the transport of the pallet 5a is restricted and stop driving the drive roller 11. The pallet 5 in the second area 91 may be detected, for example, using a photoelectric sensor (not shown) attached between the placement positions 22a and 22b or near the front side of the carry-in entrance 41. A contact-type displacement sensor may also be provided in the restriction units 70a and 70b to detect contact with the pallet 5a.

In addition, the pallet conveying devices 1, 2 may also include a return conveying section 100 that conveys the pallet 5 placed at the product placement position 4 forward, as shown in Figure 1 or 2, for example. The return conveying section 100 extends from the first area 90 to the second area 91 via the partition wall section 30. A pallet removal section 101 is disposed at the front end of the first area 90 of the return conveying section 100. An operator can remove the pallet 5 from the pallet removal section 101. This allows the operator to remove the pallet 5 with the products 3 placed on it from the first area 90.

(1) The pallet conveying devices 1 and 2 according to the embodiments include a conveying section 10 that extends along the conveying direction of a pallet 5 having a rectangular shape in a plan view and that is capable of conveying the pallet 5 while maintaining the orientation of the pallet 5 relative to the conveying direction, a partition wall section 30 that is provided between an upstream section 13 and a downstream section 14 in the conveying direction of the conveying section 10 and that divides the conveying section 10 and its surrounding area into a first area 90 that includes the upstream section 13 and a second area 91 that includes the downstream section 14, and a partition wall section 30 that is provided in the upstream section 13. The conveying section 10 includes a pallet placement section 20 on which a pallet 5 can be placed, a widthwise positioning section 50 disposed on one side of the pallet placement section 20 in a horizontal width direction perpendicular to the conveying direction and having a pallet abutment section 51 that can position the pallet 5 in the width direction by abutting an edge 6a on one side of the width direction of the pallet 5 placed on the pallet placement section 20, and restricting sections 70a, 70b disposed between the pallet placement section 20 and the partition wall section 30 on the other side of the width direction of the conveying section 10. In the second region 91, the pallet 5 is allowed to pass within a predetermined tolerance range 92 in the width direction of the conveying section 10, and the pallet abutment section 51 and the widthwise end sections 71a, 71b of the restricting sections 70a, 70b are located within the predetermined tolerance range 92 in the width direction.

With the pallet conveying devices 1 and 2 according to the embodiments, the pallet 5 can be placed on the pallet placement section 20 from at least the other widthwise side of the pallet placement section 20. The widthwise positioning unit 50 allows the pallet 5 to be positioned more reliably. Furthermore, if a pallet 5a is positioned such that it would become stuck in the second area 91 during transport, it will mechanically interfere with the restricting units 70a and 70b during transport, preventing it from being transported downstream in the transport direction. This prevents the pallet 5a from being transported to the second area 91. This allows a worker in the first area 90 to reposition the pallet 5a to a position where it will not become stuck in the second area 91 during transport. This in turn prevents workers from entering the second area 91, where automatic processing equipment and the like are located.

(2) The pallet conveying devices 1 and 2 according to the present embodiment include a first device 40 having an inlet 41 connected to the downstream section 14, through which the pallet 5 is brought in in the position it was in when it passed through the partition wall section 30. The end 41a on one widthwise side of the inlet 41 is located widthwise outside the pallet abutment section 51 of the widthwise positioning section 50, and the end 41b on the other widthwise side of the inlet 41 is located widthwise outside the ends 71a and 71b on one widthwise side of the regulating sections 70a and 70b.

The pallet conveying devices 1 and 2 according to the present embodiment include a first device 40 having an inlet 41. Pallets 5a positioned such that they would become stuck at the inlet 41 during transport mechanically interfere with the restricting units 70a and 70b during transport, preventing them from being transported downstream in the transport direction. This prevents the pallet 5a from being transported to the second area 91. This allows a worker in the first area 90 to reposition the pallet 5a so that it will not become stuck at the inlet 41 during transport. This in turn prevents workers from entering the second area 91, where the automatic processing equipment and the first device 40 are located.

(3) In the pallet conveying devices 1 and 2 according to the embodiments, when viewed in the axial direction parallel to the width direction, the pallet abutment portion 51 and the end portions 71a and 71b on one side of the width direction of the regulating portions 70a and 70b at least partially overlap.

With the pallet conveying devices 1 and 2 according to the embodiments, when the pallet 5a comes into contact with the restricting portions 70a and 70b during conveyance, the edge 6a on one widthwise side of the pallet 5a can come into contact with the pallet contact portion 51. This restricts movement of the pallet 5a to one widthwise side of the conveying unit 10. This more reliably causes mechanical interference between the pallet 5a and the restricting portions 70a and 70b. This more reliably prevents the pallet 5a from being conveyed downstream in the conveying direction. This more reliably prevents the pallet 5a from being conveyed to the second region 91.

(4) The pallet conveying devices 1 and 2 according to the present embodiment are equipped with conveying direction positioning units 60a and 60b that are arranged on one side of the pallet placement unit 20 in the conveying direction and can position the pallet 5 in the conveying direction by abutting the edges 6b and 6d on one side of the pallet 5 in the conveying direction that are placed on the pallet placement unit 20.

In the pallet conveying devices 1 and 2 according to the present embodiment, the conveying direction positioning units 60a and 60b can more reliably position the pallet 5 in the conveying direction on the pallet loading unit 20.

(5) In the pallet conveying device 2 according to the second embodiment, the conveying direction positioning unit 60b is arranged between the pallet placement unit 20 and the partition wall unit 30 so as to be movable in the width direction.

In the pallet conveying device 2 according to the second embodiment, the conveying direction positioning unit 60b is disposed downstream in the conveying direction of the pallet placement unit 20 in the first region 90. This means that when the pallet 5 is placed from the front side of the pallet placement unit 20 during the pallet placement process, the conveying direction positioning unit 60b does not interfere with the placement operation. This makes it easier to place the pallet 5 on the pallet placement unit 20.

(6) In the pallet conveying device 2 according to the second embodiment, the regulating portion 70b includes a conveying direction positioning portion 60b.

In the pallet conveying device 2 according to the second embodiment, the conveying direction positioning unit 60b is included in the regulating unit 70b. This allows some of the components that make up the regulating unit 70b to be shared with the components that make up the conveying direction positioning unit 60b. This reduces the number of components that make up the pallet conveying device 2 according to the embodiment, making it easier to configure the pallet conveying device 2.

DESCRIPTION OF SYMBOLS 1, 2 Pallet transport device 3 Product 4 Product placement position 5, 5a Pallet 6a, 6b, 6c, 6d Edge portion 7 Pallet outer end 8 Operation unit 10, 10a, 10b Transport unit 11 Drive roller 12 Cover portion 13 Upstream portion 14 Downstream portion 20 Pallet placement portion 21 Middle portion 22a Placement position 22b Placement position 30 Partition wall portion 31 Fence portion 32 Object detection area 33 Partition opening 40 First device 41 Carry-in entrance 41a End portion 41b End portion 42 Rear wall portion 43a, 43b Side wall portion 44a, 44b Front end portion 45a, 45b Tapered surface 46 Pallet lifting device 47 Internal space 50 Width direction positioning portion 51 Pallet abutment portion 52 Pallet abutment surface 60a, 60b Transport direction positioning portion 61 Pallet abutment portion 62 Pallet contact surface 63 Pallet contact portion 64 Pallet contact surfaces 70a, 70b Restriction portion 71a, 71b End portion 72a, 72b Extension portion 73 Grip portion 74 Support portion 80a, 80b Virtual surface 90 First region 91 Second region 92 Predetermined tolerance range 100 Return path conveyance portion 101 Pallet removal portion

Claims (4)

a conveying unit that extends along a conveying direction of a pallet having a rectangular shape in a plan view and is capable of conveying the pallet while maintaining the orientation of the pallet with respect to the conveying direction;
a partition wall portion provided between an upstream portion and a downstream portion of the conveying portion in the conveying direction, the partition wall portion dividing the conveying portion and its surrounding area into a first area including the upstream portion and a second area including the downstream portion;
a pallet placement section disposed in the upstream section and capable of placing the pallet;
a width direction positioning unit that is disposed on one side of the pallet placement unit in a horizontal width direction perpendicular to the conveying direction, and has a pallet abutment portion that can position the pallet in the width direction by abutting an edge portion of the one side in the width direction of the pallet placed on the pallet placement unit;
a regulating section disposed between the pallet placement section and the partition wall section on the other side of the conveying section in the width direction;
a conveyance direction positioning section that is disposed on one side of the pallet placement section in the conveyance direction and that is capable of positioning the pallet in the conveyance direction by abutting an edge portion of the pallet placed on the pallet placement section on the one side in the conveyance direction;
Equipped with
In the second region, the pallet is allowed to pass through within a predetermined allowable range in the width direction of the conveying section,
the pallet abutment portion and the end portion on one side in the width direction of the regulating portion are located inside the predetermined tolerance range in the width direction,
the conveying direction positioning unit is disposed between the pallet placement unit and the partition wall unit so as to be movable in the width direction;
Pallet transport device. a first device having an inlet connected to the downstream portion, into which the pallet is carried in the attitude when it passed through the partition wall portion;
an end portion on one side in the width direction of the carry-in entrance is positioned outside the pallet abutment portion of the width direction positioning portion in the width direction;
The pallet transport device according to claim 1 , wherein the other widthwise end of the entrance is positioned outside the one widthwise end of the restricting portion. A pallet conveying device according to claim 1 or 2, wherein, when viewed in an axial direction parallel to the width direction, the pallet abutment portion and the end portion of the regulating portion on one side in the width direction at least partially overlap. The pallet conveying device according to claim 1 , wherein the regulating portion includes the conveying direction positioning portion.