Visual inspection device

Abstract

To provide a visual inspection device that can inspect the front and back surfaces of a workpiece with high precision. [Solution] The visual inspection device 1 includes an inversion guide member 15 that, on the +Y direction side of the tail pulley 113 of the belt conveyor 11, faces and curves along the winding portion around which the belt 111 is wound on the tail pulley 113 from the vertically upper side to the vertically lower side, and guides the workpiece that has been conveyed to the end of the belt conveyor 11 on the +Y direction side to be transferred to the belt conveyor 12 in an inverted state; an imaging unit 13 that faces from vertically above the portion of the belt 111 that is located vertically above the head pulley 112 and the tail pulley 113; and an imaging unit 14 that faces from vertically above the portion of the belt 121 that is located vertically above the portion between the head pulley 122 and the tail pulley 123.

Description

Technical Field

[0001] The present invention relates to an appearance inspection device.

Background Art

[0002] An appearance inspection device has been proposed that images the inner and outer surfaces of a cap to be inspected (see, for example, Patent Document 1). First, this appearance inspection device places the caps in a matrix on a transparent plate, conveys them along the upper surface of the transparent plate while pushing each row with a pusher rod, and images the inner surface of the cap from below the transparent plate with an inner surface inspection camera during this process. Next, the appearance inspection device conveys the caps to a turret table through a first belt conveyor and a second belt conveyor, receives them one by one in pockets, then transfers them in the rotational direction of the turret table while holding the inner surface of the cap, and images the cap from the side and above with an outer peripheral surface inspection camera and a top surface inspection camera while pushing up the cap at the inspection position and rotating it.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, since the appearance inspection device described in Patent Document 1 images the inner surface of the cap through a transparent plate, there is a risk of misrecognizing, for example, foreign matter adhering to the transparent plate as an abnormality on the inner surface of the cap. Therefore, there is a risk of incorrect sorting of the caps.

[0005] The present invention has been made in view of the above reasons, and an object thereof is to provide an appearance inspection device capable of inspecting the appearance of the front and back of a workpiece with high accuracy.

Means for Solving the Problems

[0006] To achieve the above objective, the visual inspection apparatus according to the present invention is A first belt conveyor having two first pulleys spaced apart from each other and with their rotation axes parallel, and a first belt stretched between the two first pulleys, which conveys a workpiece in a second direction when viewed from a first direction along the rotation axis of the first pulleys, A second belt conveyor for transporting the workpiece in the second direction, comprising: two second pulleys spaced apart from each other and with their rotation axes parallel; a second belt stretched between the two second pulleys, with a portion of it facing one of the two first pulleys vertically below the one on the second direction side; On the opposite side of one of the two first pulleys from the other, a reversal guide member is provided, which curves from vertically upward to vertically downward, facing the winding portion around which the first belt is wound on the first pulley, and along the winding portion, and guides the workpiece that has been conveyed to the end of the first belt conveyor on the second direction side to be transferred to the second belt conveyor in an inverted state, A first imaging unit is positioned vertically above the portion of the first belt located vertically above the two first pulleys, and The second belt comprises a second imaging unit positioned vertically above the portion located vertically above the two second pulleys, and facing it from vertically above. [Effects of the Invention]

[0007] According to the present invention, the reversal guide member is located on the opposite side of the second direction side of one of the two first pulleys of the first belt conveyor, and curves from vertically upward to vertically downward, facing and along the winding portion around which the first belt is wound on one of the pulleys, guiding the workpiece that has been conveyed to the end of the second direction side of the first belt conveyor to be reversed and then transferred to the second belt conveyor. As a result, the front and back appearances of the workpiece can be directly imaged by the first imaging unit and the second imaging unit, respectively, so that the front and back appearances of the workpiece can be inspected with high precision. [Brief explanation of the drawing]

[0008] [Figure 1] This is a front view of the visual inspection device according to Embodiment 1 of the present invention. [Figure 2] This is an explanatory diagram of the operation of the visual inspection apparatus according to Embodiment 1, where (A) shows the workpiece being imaged by the first imaging unit, (B) shows the workpiece being transferred from the first belt conveyor to the second belt conveyor by the reversing guide member, and (C) shows the workpiece being imaged by the second imaging unit. [Figure 3] This is a front view of the visual inspection device according to Embodiment 2 of the present invention. [Figure 4] This is a plan view of the visual inspection device according to Embodiment 2. [Figure 5] The guide portion of the horizontal guide member according to Embodiment 2 is shown, where (A) is a perspective view and (B) is a perspective view taken from a different direction than (A). [Figure 6] This is an explanatory diagram of the operation of the visual inspection apparatus according to Embodiment 2, where (A) shows the process of transporting the workpiece on the guide section along the direction of movement of the first belt, (B) shows the process of changing the transport direction of the workpiece on the guide section toward the second belt conveyor, and (C) shows the process of pushing the workpiece on the guide section toward the second belt conveyor. [Figure 7] This is a front view of the visual inspection device related to a modified example. [Figure 8] This is a front view of the visual inspection device related to a modified example. [Modes for carrying out the invention]

[0009] (Embodiment 1) The visual inspection apparatus according to this embodiment comprises a first belt conveyor, a second belt conveyor, a reversing guide member, a first imaging unit, and a second imaging unit. The first belt conveyor has two first pulleys spaced apart from each other and with parallel rotation axes, and a first belt stretched between the two first pulleys, and conveys the workpiece in a second direction when viewed from a first direction along the rotation axis of the first pulleys. The second belt conveyor has two second pulleys spaced apart from each other and with parallel rotation axes, and a second belt stretched between the two second pulleys, with a portion of it facing one of the first pulleys on the second direction side vertically below that first pulley, and conveys the workpiece in a second direction. The reversal guide member is positioned on the opposite side of one of the two first pulleys from the other first pulley, and curves from vertically upward to vertically downward, facing and along the winding portion around which the first belt is wrapped on one of the first pulleys, guiding the workpiece that has been conveyed to the end of the first belt conveyor on the second direction side to be transferred to the second belt conveyor in an inverted state. The first imaging unit is positioned facing the portion of the first belt located vertically upward between the two first pulleys, and images the workpiece placed on the first belt. The second imaging unit is positioned facing the portion of the second belt located vertically upward between the two second pulleys, and images the workpiece placed on the second belt.

[0010] As shown in Figure 1, the visual inspection device 1 according to this embodiment comprises two belt conveyors 11 and 12, a reversal guide member 15, and two imaging units 13 and 14. The visual inspection device 1 also comprises a base member 161, a pulley support part 162 erected on the base member 161 and rotatably pivoting the head pulley 112 of the belt conveyor 11 at its tip, and a pulley support part 163 erected on the base member 161 and rotatably pivoting the tail pulley 113 of the belt conveyor 11 at its tip. Furthermore, the visual inspection device 1 comprises a pulley support part 164 erected on the base member 161 and rotatably pivoting the head pulley 122 of the belt conveyor 12 at its tip, and a pulley support part 165 erected on the base member 161 and rotatably pivoting the tail pulley 123 of the belt conveyor 12 at its tip. In this visual inspection device 1, for example, the visual appearance of the front surface Wf and the back surface Wb of the workpiece W, which is a cap, are sequentially captured by the imaging units 13 and 14, and the captured images are used to perform the visual inspection.

[0011] The belt conveyor 11 includes a head pulley 112 and a tail pulley 113 that are spaced apart from each other and have parallel axis of rotation, a belt 111 stretched between the head pulley 112 and the tail pulley 113, and a pulley drive unit 114 that drives the belt 111 to rotate in the direction indicated by arrow AR11. The belt conveyor 11 transports a workpiece W placed on the portion of the belt 111 located on the +Z direction side between the head pulley 112 and the tail pulley 113 in a second direction when viewed from the +X direction, i.e., the +Y direction, along the axis of rotation of the head pulley 112 and the tail pulley 113. The belt 111 is, for example, a rubber belt and has an annular belt body 111a and a plurality of protrusions 111b that are arranged at equal intervals along the extending direction of the belt body 111a and protrude outwards from the belt body 111a. The tail pulley 113 has a cylindrical main wheel 113a around which the belt 111 is wound, and a transmission wheel 113b that is coaxially positioned with the main wheel 113a on the +X side and rotates together with the main wheel 113a. The pulley drive unit 114 has a drive pulley 1141, a rotational drive unit 1142 that rotates the drive pulley 1141, and a drive belt 1143 stretched between the transmission wheel 113b of the tail pulley 113 and the drive pulley 1141. The rotational drive unit 1142 rotates the drive pulley 1141, thereby rotating the tail pulley 113 via the drive belt 1143.

[0012] The belt conveyor 12 includes a head pulley 122 and a tail pulley 123 that are spaced apart from each other and have parallel axes of rotation, a belt 121 stretched between the head pulley 122 and the tail pulley 123, and a pulley drive unit 124 that drives the belt 121 to rotate in the direction indicated by arrow AR12. This belt conveyor 12 transports a workpiece W placed on the portion of the belt 121 located on the +Z side between the head pulley 122 and the tail pulley 123 in the +Y direction. The belt 121 is, for example, a rubber belt and has an annular belt body 121a and a plurality of protrusions 121b that are arranged at equal intervals along the extending direction of the belt body 121a and protrude outwards from the belt body 121a. In addition, the portion of the belt 121 near the -Y side end faces the tail pulley 113 of the belt conveyor 11 vertically below it, i.e., on the -Z side. The head pulley 122 has a cylindrical main wheel 122a around which the belt 121 is wound, and a transmission wheel 122b that is coaxially positioned with the main wheel 122a on the +X side and rotates together with the main wheel 122a. The pulley drive unit 124 rotates the head pulley 122 so that the belt 121 moves circumferentially in the same direction as the circumferential movement of the belt 111. The pulley drive unit 124 also has a drive pulley 1241, a rotational drive unit 1242 that rotates the drive pulley 1241, and a drive belt 1243 stretched between the transmission wheel 122b of the head pulley 122 and the drive pulley 1241. The rotational drive unit 1242 rotates the drive pulley 1241, thereby rotating the head pulley 122 via the drive belt 1243.

[0013] The reverse guide member 15 has a guide portion 151 and a guide support portion 152 that supports the guide portion 151. The guide portion 151 faces and curves along the winding portion where the belt 111 is wound around the tail pulley 113 from the vertically upper side to the vertically lower side on the side opposite to the head pulley 112 side of the tail pulley 113 of the belt conveyor 11, that is, on the +Y direction side. Then, the guide portion 151 guides the work W conveyed to the end portion on the +Y direction side of the belt conveyor 11 to slide along the inner curved portion of the guide portion 151 and be reversed and transferred to the belt conveyor 12.

[0014] The imaging unit 13 is an imaging device such as a visible light camera or an infrared camera, and is disposed to face from directly above in the vertically upper side, that is, the +Z direction side, between the head pulley 112 and the tail pulley 113 of the belt 111 of the belt conveyor 11. Then, the imaging unit 13 images the work W placed on the portion located on the +Z direction side between the head pulley 112 and the tail pulley 113 of the belt 111.

[0015] The imaging unit 14 is an imaging device such as a visible light camera or an infrared camera, and is disposed to face from directly above in the +Z direction side between the head pulley 122 and the tail pulley 123 of the belt 121 of the belt conveyor 12. Then, the imaging unit 14 images the work W placed on the portion located on the +Z direction side between the head pulley 122 and the tail pulley 123 of the belt 121. Here, when the imaging unit 14 images the surface Wf of the work W, the imaging unit 14 images the back surface Wb of the work W.

[0016] Next, the operation of the appearance inspection apparatus 1 according to the present embodiment will be described with reference to FIG. 2. First, as shown in FIG. 2(A), the work W is placed near the -Y-direction end of the portion located on the +Z-direction side between the head pulley 112 and the tail pulley 113 of the belt 111 of the belt conveyor 11. Here, the work W is placed on the belt 111, for example, with its surface Wf facing vertically upward. Then, when the belt conveyor 11 conveys the work W to directly below the imaging unit 13 as indicated by the arrow AR21, the imaging unit 13 images the surface Wf of the work W placed on the belt 111. Next, when the belt conveyor 11 further conveys the work W in the direction indicated by the arrow AR21 and the work W reaches the +Y-direction end of the belt conveyor 11, the work W slides down along the curved portion inside the guide portion 151 of the inversion guide member 15 as indicated by the arrow AR22 in FIG. 2(B). Then, the work W is transferred to the belt conveyor 12 in a state where the front and back are inverted. Subsequently, when the belt conveyor 12 conveys the work W to directly below the imaging unit 14 as indicated by the arrow AR23, the imaging unit 13 images the surface Wf of the work W placed on the belt 111.

[0017] As described above, according to the packaging machine according to the present embodiment, the inversion guide member 15 has a guide portion 151 that faces the winding portion around which the belt 111 is wound on the tail pulley 113 from the vertically upper side to the vertically lower side on the +Y-direction side of the tail pulley 113 of the belt conveyor 11 and is curved along the winding portion, and guides the work W conveyed to the +Y-direction end of the belt conveyor 11 to be transferred to the belt conveyor 12 after being inverted. Thereby, since the appearance of the front and back surfaces Wf and Wb of the work W can be directly imaged by each of the imaging units 13 and 14, the appearance of the front and back of the work W can be inspected with high accuracy.

[0018] (Embodiment 2) The visual inspection apparatus according to this embodiment differs from Embodiment 1 in that, along with the reversing guide member, it includes a horizontal guide member that guides the workpiece discharged from the reversing guide member toward the second belt conveyor in a horizontal direction perpendicular to the vertical direction. Here, the judgment guide member is located on the opposite side of one of the two third pulleys from the other side, and curves from the vertically upper side to the vertically lower side, facing and along the winding portion around which the third belt on one of the third pulleys is wound, and discharges the workpiece that has been conveyed to the end of the second direction side of the third belt conveyor toward the vertically lower side in an inverted state.

[0019] As shown in Figure 3, the visual inspection device 2001 according to this embodiment includes two belt conveyors 11 and 2012, a reversing guide member 2015, a horizontal guide member 2017, and two imaging units 13 and 14. In Figure 3, components similar to those in Embodiment 1 are denoted by the same reference numerals as in Figure 1. The visual inspection device 1 also includes a base member 161, pulley support parts 162 and 163, a pulley support part 2164 erected on the base member 161 and pivotally supporting the head pulley 2122 of the belt conveyor 2012 (described later) at its tip, and a pulley support part 2165 erected on the base member 161 and pivotally supporting the head pulley 2122 of the belt conveyor 2012 (described later) at its tip.

[0020] Belt conveyor 11 includes a head pulley 112 and a tail pulley 113, a belt 111 stretched between the head pulley 112 and the tail pulley 113, and a pulley drive unit (not shown) that rotates the tail pulley 113 to drive the belt 111 in the direction indicated by arrow AR31. Belt conveyor 2012 includes a head pulley 2122 and a tail pulley 2123 that are spaced apart from each other and have parallel axes of rotation, and a belt 121 stretched between the head pulley 2122 and the tail pulley 2123. Belt conveyor 2012 also includes a pulley drive unit (not shown) that rotates the tail pulley 2123 to drive the belt 121 in the direction indicated by arrow AR22. This belt conveyor 2012 transports the workpiece W, which is placed on the portion of the belt 121 located on the +Z side between the head pulley 2122 and the tail pulley 2123, in the +Y direction. Furthermore, as shown in Figures 3 and 4, the portion of the belt 121 near the -Y side end is located vertically below the tail pulley 133 of the belt conveyor 11 and offset in the direction of the rotation axis of the tail pulley 133, i.e., offset in the +X direction.

[0021] The reversal guide member 2015 has a guide portion 2151 and a guide support portion 2152 that supports the guide portion 2151. The guide portion 2151 is curved on the +Y direction side of the tail pulley 113 of the belt conveyor 11, facing the wound portion of the belt 111 on the tail pulley 113 from the vertically upper side to the vertically lower side, and along the wound portion. The guide portion 151 guides the workpiece W, which has been conveyed to the end of the belt conveyor 11 on the +Y direction side, to be reversed by sliding down along the curved portion on the inside of the guide portion 151 and transferred to the horizontal guide member 2017.

[0022] As shown in Figure 3, the horizontal guide member 2017 has a guide portion 2171 and a guide support portion 2172 that supports the guide portion 2171, and the guide portion 2171 is positioned to face from vertically below the portion located vertically below the head pulley 112 and tail pulley 113 on the belt 111 of the belt conveyor 11. As shown in Figures 5(A) and (B), the guide portion 2171 has a guide portion body 21711 in which a guide groove 21711a is formed that guides the workpiece W entering along the circular trajectory direction of the belt 111 of the belt conveyor 11 in the vertical direction and in a direction perpendicular to the direction of entry of the workpiece W, i.e., in the +X direction. Furthermore, the guide portion 2171 includes a rib 21712 erected along the guide groove 21711a on the outer circumference on the -X side of the guide groove 21711a on the +Z side of the guide portion body 21711, and two ribs 21713 and 21714 erected along the guide groove 21711a on the outer circumference on the +X side of the guide groove 21711a on the +Z side of the guide portion body 21711. Here, the guide portion 2171 is positioned such that the first distance between the region A1 extending along the circumferential trajectory direction of the belt 111, at least on the outer circumference of the guide groove 21711a on the +Z direction side of the guide portion body 21711, facing the plurality of protrusions 111b of the belt 111 of the belt conveyor 11, and the belt body 111a of the belt 111 is greater than the height in the protruding direction of each of the plurality of protrusions 111b, and the second distance between the region A1 at the bottom of the guide groove 21711a and the belt body 111a is greater than the vertical thickness of the workpiece W. Furthermore, the guide portion 2171 is positioned such that the third distance between the region A1 at the bottom of the guide groove 21711a and the tip of each of the plurality of protrusions 111b of the belt 111 is smaller than the vertical thickness of the workpiece W. As a result, the workpiece W placed inside the guide groove 21711a of the guide section 21711 is pushed in the -Y direction by the tip of the projection 111b of the belt 111 of the belt conveyor 11, and is transported in the -Y direction within the guide groove 21711a.

[0023] Next, the operation of the visual inspection device 2001 according to this embodiment will be described with reference to Figure 6. First, the workpiece W discharged from the reversing guide member 2015 is fed into the guide groove 21711a of the guide body 21711 of the guide section 2171 on the +Y side. Next, as shown in Figure 6(A), the workpiece W is pushed in the -Y direction by the tip of the projection 111b of the belt 111 of the belt conveyor 11, and is transported in the -Y direction within the guide groove 21711a as shown by arrow AR41. Subsequently, as the workpiece W is further pushed in the -Y direction by the tip of the projection 111b, the workpiece W is pushed out along the guide groove 21711a on the +X side as shown by arrow AR42 in Figure 6(B). After that, as shown by arrow AR43 in Figure 6(C), the workpiece W is further pushed out on the +X side by the tip of the projection 111b and transferred to the belt 121 of the belt conveyor 12.

[0024] As described above, according to the visual inspection device 2001 of this embodiment, the workpiece W discharged from the reversing guide member 2015 first moves through the guide groove 21711a of the guide portion 2171 of the horizontal guide member 2017 before being transferred to the belt 121 of the belt conveyor 2012. This reduces the impact applied to the workpiece W when it is transferred from the belt conveyor 11 to the belt conveyor 2012, thereby reducing the problem of the inverted workpiece W being reversed again due to the impact and causing the imaging unit 14 to image the surface Wf of the workpiece W. Therefore, the front and back surfaces of the workpiece W can be properly inspected.

[0025] Although various embodiments of the present invention have been described above, the present invention is not limited to the embodiments described above. For example, the belts 111 and 121 may be made by connecting metal or resin footplates in a ring shape.

[0026] In Embodiment 1, for example, as shown in the visual inspection device 3001 in Figure 7, the belt 3121 of the belt conveyor 3012 may be a so-called flat belt made of rubber with no protrusions and an annular shape. Also, in Embodiment 2, for example, as shown in the visual inspection device 4001 in Figure 8, the belt 3121 of the belt conveyor 4012 may be a so-called flat belt made of rubber with no protrusions and an annular shape.

[0027] By the way, in the case of belt conveyors 12 and 2012 equipped with a belt 121 having a plurality of protrusions 121a as described in Embodiments 1 and 2, when a workpiece W is transferred from the reversing guide member 15 or the horizontal guide member 2017 to the belt 121, depending on the timing of the transfer, the workpiece W may collide with the protrusions 121a and become stuck between the lower end of the reversing guide member 15 or the tip of the guide groove 21711a of the horizontal guide member 2017 and the protrusions 121a. In this case, the belt conveyors 12 and 2012 may stop, and the operating rate of the visual inspection devices 1 and 2001 may decrease.

[0028] In contrast, in this configuration, since the belt conveyors 3012 and 4012 have belts 3121 without protrusions, the workpiece W is smoothly transferred from the reversing guide member 15 or the horizontal guide member 2017 to the belt 3121, regardless of the timing of the transfer of the workpiece W from the reversing guide member 15 or the horizontal guide member 2017 to the belt 3121. Therefore, problems such as the workpiece W getting caught between the lower end of the reversing guide member 15 or the tip of the guide groove 21711a of the horizontal guide member 2017 and the belt 3121 can be suppressed, which has the advantage of increasing the operating rate of the visual inspection devices 3001 and 4001. [Industrial applicability]

[0029] This invention is particularly suitable for processes such as inspecting and sorting the appearance of caps by examining the front and back surfaces. [Explanation of symbols]

[0030] 1,2001,3001,4001: Visual inspection device, 11,12,2012,3012,4012: Belt conveyor, 13,14: Imaging unit, 15: Reversing guide member, 111,121,3121: Belt, 111a,121a: Belt body, 111b,121b: Protrusion, 112,122,2122: Head pulley, 113,123,2123: Tail pulley, 113a,122a: Main wheel, 113b,122b: Transmission wheel, 114,124: Pulley drive unit, 15 1,2151,2171: Guide section, 152,2152,2172: Guide support section, 161: Base member, 162,163,164,165,2164,2165: Pulley support section, 1141,1241: Drive pulley, 1142,1242: Rotary drive section, 1143,1243: Drive belt, 2017: Horizontal guide member, 21711: Guide section body, 21711a: Guide groove, 21712,21713,21714: Rib, W: Workpiece, Wf: Front surface, Wb: Back surface

Claims

1. A first belt conveyor having two first pulleys spaced apart from each other and with their rotation axes parallel, and a first belt stretched between the two first pulleys, which conveys a workpiece in a second direction when viewed from a first direction along the rotation axis of the first pulleys, A second belt conveyor for transporting the workpiece in the second direction includes two second pulleys spaced apart from each other and with their rotation axes parallel, and a second belt stretched between the two second pulleys, with a portion of it facing one of the two first pulleys vertically below the one on the second direction side. On the opposite side of one of the two first pulleys from the other, a reversal guide member is provided, which curves from the vertically upper side to the vertically lower side, facing the winding portion around which the first belt is wound on the first pulley, and along the winding portion, and guides the workpiece that has been conveyed to the end of the first belt conveyor on the second direction side to be transferred to the second belt conveyor in an inverted state, A first imaging unit is positioned vertically above the portion of the first belt located vertically above the two first pulleys, and The second belt comprises a second imaging unit positioned vertically above the portion located vertically above the two second pulleys, Visual inspection device.

2. The first belt conveyor has a first pulley drive unit that rotationally drives at least one of the two first pulleys, The second belt conveyor has a second pulley drive unit that rotates at least one of the two second pulleys so that the second belt moves in the same direction as the first belt moves in the same direction. The appearance inspection apparatus according to claim 1.

3. The second belt is a flat belt. The appearance inspection apparatus according to claim 1 or 2.

4. A third belt conveyor having two third pulleys spaced apart from each other and with their rotation axes parallel, and a third belt stretched between the two third pulleys, which conveys a workpiece in a fourth direction when viewed from a third direction along the rotation axis of the third pulleys, A fourth belt conveyor for transporting the workpiece in the fourth direction, comprising: two fourth pulleys spaced apart from each other and with their rotation axes parallel; a fourth belt stretched between the two fourth pulleys, with a portion of it positioned vertically below one of the two third pulleys on the fourth direction side and offset in the direction of the rotation axis; On the opposite side of one of the two third pulleys from the other, a reversal guide member is provided, which is curved from the vertically upper side to the vertically lower side, facing the winding portion around which the third belt of the one pulley is wound, and along the winding portion, and which discharges the workpiece that has been conveyed to the end of the third belt conveyor on the fourth side in an inverted state to the vertically downward side, A horizontal guide member guides the workpiece discharged from the reversing guide member toward the fourth belt conveyor in a horizontal direction perpendicular to the vertical direction, A third imaging unit is positioned vertically above the portion of the third belt located vertically above the two third pulleys, and The fourth belt comprises a fourth imaging unit positioned vertically above the portion located vertically above the two fourth pulleys, and facing it from vertically above. Visual inspection device.

5. The horizontal guide member has guide grooves formed therein that guide the workpiece entering along the circumferential trajectory direction of the third belt of the third belt conveyor in the vertical direction and in a direction perpendicular to the direction in which the workpiece enters, and is positioned so as to face from vertically below the portion located vertically below the two third pulleys on the third belt. The appearance inspection apparatus according to claim 4.

6. The aforementioned third belt is The annular belt body, The belt body has a plurality of protrusions that protrude outward from the outside, The horizontal guide member is arranged such that a first distance between the belt body and a region extending along the circumferential trajectory direction, at least on the outer circumference of the guide groove and facing the plurality of protrusions, is greater than the height in the protruding direction of each of the plurality of protrusions; a second distance between the belt body and the bottom region of the guide groove is greater than the vertical thickness of the workpiece; and a third distance between the bottom region of the guide groove and the tip of each of the plurality of protrusions is smaller than the vertical thickness of the workpiece. The appearance inspection apparatus according to claim 5.

7. The previous fourth belt is a flat belt. The appearance inspection apparatus according to any one of claims 4 to 6.

Images