VISION ENABLED APPARATUS FOR SORTING PARTS AND SYSTEMS AND METHODS THEREFOR
20190388939 ยท 2019-12-26
Assignee
Inventors
- Glen Albert Bell (Waterloo, CA)
- Joshua Bailey (Listowel, CA)
- Angelos KOTZAMBASIS (Waterloo, CA)
- John Crocker (Waterloo, CA)
- Matthew BORDMAN (St. Marys, CA)
- Mark De Groot (Poole, CA)
Cpc classification
B07C5/3422
PERFORMING OPERATIONS; TRANSPORTING
B07C5/20
PERFORMING OPERATIONS; TRANSPORTING
B07C1/04
PERFORMING OPERATIONS; TRANSPORTING
B07C5/342
PERFORMING OPERATIONS; TRANSPORTING
International classification
B07C1/04
PERFORMING OPERATIONS; TRANSPORTING
B07C5/36
PERFORMING OPERATIONS; TRANSPORTING
Abstract
A parts feeder which incorporates a position-controlled conveyor, a unique flex crowder system and destacker for promoting the singulation of parts on the conveyor, and a vision enabled reject mechanism to select and reject non-compliant parts. In this regard, parts to be sorted are lifted onto a conveyor and run past a series of adjustable crowder sections, including a flex crowder section, past a destacker element and into a singulation zone whereupon multiple camera images of both edges and features in conjunction with conveyor speed, conveyor position and laser triggering synchronize the parts to be rejected. The parts feeder incorporates adjustable settings thereby obviating the need to switch out components for the purpose of accommodating parts of various shapes and sizes.
Claims
1. A parts feeder for singulating parts, comprising: a hopper for receiving parts; a conveyor for transporting parts; a lift operatively connected to an end of the hopper for driving received parts to the conveyor; a crowder landing member positioned substantially perpendicular to the upper surface of the conveyor, the crowder landing member disposed in the vicinity of the path of exit of the lift, the crowder landing member adapted for movement within a horizontal plane forward and away from the conveyor; a singulator crowder member positioned substantially perpendicular to the upper surface of the conveyor, the singulator crowder member disposed downstream from the crowder landing member, the singulator crowder member adapted for movement within a horizontal plane forward and away from the conveyor; and a flex crowder member disposed between and connected to each of the crowder landing member and the singulator crowder member, the flex crowder member comprised of a flexible material for facilitating the movement of parts along the conveyor, including where the crowder landing member and singulator crowder member are not aligned in relation to the conveyor.
2. The parts feeder of claim 1 wherein the lift is of a fixed depth.
3. The parts feeder of claim 1 wherein the lift is housed in a feeder housing.
4. The parts feeder of claim 1 further comprising a destacker disposed between the crowder landing member and the singulator crowder member on the same side of the conveyor as the crowder landing member and the singulator crowder member, the destacker moveable in a vertical plane perpendicular to the upper surface of the conveyor, the destacker functioning to deflect stacked parts or prevent the movement of parts of undesired shape or size past the destacker.
5. The parts feeder of claim 4 wherein the destacker has an angled lower edge.
6. The parts feeder of claim 5 wherein the angle is between 4 and 10 degrees.
7. The parts feeder of claim 4 wherein the destacker is attached to the leading edge of the singulator crowder member.
8. The parts feeder of claim 1 wherein the flex crowder member changes in shape in relation to the length of the conveyor adjacent to the flex crowder member in response to the movement of the crowder landing member and the singulator crowder member forward and/or away from the conveyor.
9. A parts feeder for sorting parts, comprising: a hopper for receiving parts; a conveyor for transporting parts; a lift operatively connected to an end of the hopper for driving received parts to the conveyor; a crowder landing member positioned substantially perpendicular to the upper surface of the conveyor, the crowder landing member disposed in the vicinity of the path of exit of the lift, the crowder landing member adapted for movement within a horizontal plane forward and away from the conveyor; a singulator crowder member positioned substantially perpendicular to the upper surface of the conveyor, the singulator crowder member disposed downstream from the crowder landing member, the singulator crowder member adapted for movement within a horizontal plane forward and away from the conveyor; a flex crowder member disposed between and connected to each of the crowder landing member and the singulator crowder member, the flex crowder member comprised of a flexible material for facilitating the movement of parts along the conveyor, including where the crowder landing member and singulator crowder member are not aligned in relation to the conveyor; a camera positioned in the vicinity of the singulator crowder member, the camera for recording images of singulated parts on the conveyor to produce an image data set; a processor linked to the camera for analyzing the image data set and identifying parts to be removed from the conveyor; and an at least one part removal apparatus in operative communication with the processor, the at least one part removal apparatus disposed downstream from the camera, the at least one part removal apparatus operable to effect the removal a part from the conveyor.
10. The parts feeder of claim 9 further comprising a destacker disposed between the crowder landing member and the singulator crowder member on the same side of the conveyor as the crowder landing member and the singulator crowder member, the destacker moveable in a vertical plane perpendicular to the upper surface of the conveyor, the destacker functioning to deflect stacked parts or prevent the movement of parts of undesired shape or size past the destacker.
11. The parts feeder of claim 9 further comprising a bumper disposed downstream from the destacker on the same side of the conveyor as the at least one blower, the bumper for forcing rejected parts away from the singulator crowder member.
12. The parts feeder of claim 11 wherein the bumper is affixed at or near the leading edge of the singulator crowder member.
13. The parts feeder of claim 9 wherein the part removal apparatus is an at least one blower connected to an air source.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] In the drawings, preferred embodiments of the invention are illustrated by way of example. It is to be expressly understood that the drawings are only for the purpose of illustration and as an aid to understanding and are not intended as a definition of the limits of the invention. The embodiments herein will be understood from the following description with reference to the drawings, in which:
[0008]
[0009]
[0010]
[0011]
[0012]
[0013]
[0014]
[0015]
[0016]
[0017]
DETAILED DESCRIPTION OF EXAMPLE EMBODIMENTS
[0018] In this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangements of the components outlined in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of description and should not be regarded as limiting. In particular, all terms used herein are used in accordance with their ordinary meanings unless the context or definition clearly indicates otherwise. Also, unless indicated otherwise except within the claims the use of or includes and and vice-versa. Non-limiting terms are not to be construed as limiting unless expressly stated or the context clearly indicates otherwise (for example, including, having, characterized by and comprising typically indicate including without limitation). Singular forms included in the claims such as a, an and the include the plural reference unless expressly stated or the context clearly indicates otherwise. Further, the stated features and/or configurations or embodiments thereof the suggested intent may be applied as seen fit to certain operating conditions or environments by one experienced in the field of art.
[0019] In an example embodiment, as shown in
[0020] At the top end of the lift 30, parts to be sorted (not shown) are placed on the conveyor 40. The conveyor 40 is also controlled by a motor 60 (or equivalent) which can determine by use of an encoder (not shown) both the position of parts on the conveyor 40 as well as conveyer speed. In the embodiment contemplated, the encoder is an electro-mechanical device which converts the angular position of the motor 60 into digital pulses. For example, if the encoder has 360 increments, each pulse would indicate 1 degree of rotation of the shaft (not shown) of the motor 50. By operation of the encoder, the parts feeder assembly 10 is able to synchronize the cycle of the lift 30 with the speed of the conveyor 40 such that parts on the conveyor 40 will clear the deposit of a new batch of parts being placed on the conveyor. If parts are placed on the conveyor 40 without clearing the preceding batch, excessive parts are rejected, and cycle time goes down. In contrast, when the preceding parts are cleared off, cycle time goes up as system capacity increases. Still referring to
[0021] The singulator crowder member 100 is a walled member also positioned substantially perpendicular to the conveyor 40. The singulator crowder member 100 is positioned downstream from the lift 30 egress and functions to guide singulated parts along the conveyor 40 for selection. The singulator crowder member 100 is also operatively connected to an at least one adjusting rod (or movement member) 110 affixed to the feeder assembly on the side of the singulator crowder member 100. In the embodiment shown in
[0022] It should also be mentioned that the singulator crowder member 100 can also be moved close to the edge of the conveyor 40 on the side of the conveyor 40 opposite the singulator crowder member 100 in order to force non-aligned parts moving on the conveyor 40 in the vicinity of the singulator crowder member 100 back into the hopper 20.
[0023] Once parts are positioned on the moving conveyor 40 in the vicinity of the singulator crowder member 100 (e.g. parts on the conveyor adjacent to member 100), the singulator crowder member 100 is moveable to position parts in the field of view of a camera 180, which camera 180 is positioned above the conveyor 40 in the vicinity of the singulator crowder member 100.
[0024] Referring to
[0025] As previously indicated, the flex crowder 120 functions to retain and guide parts as they move along the conveyor 40. On the conveyor 40 in the vicinity of the crowder landing member 80, the parts dropped onto the conveyor 40 from the lift 30 are positioned in the staging area 70 on the conveyor 40. An alternative view of the staging area 70 is depicted in
[0026] The flex crowder 120 feature reduces or eliminates the need to employ a feeder using lifts of varying depths and widths including feeders which utilize multiple lifts of different sizes And the flex crowder member 90 which is disposed between and connected to each of the members 80, 100 makes up any difference in alignment between members 80 and 100 and thereby allows for a smooth transition of parts from the crowder landing member 80 to the singulator crowder member 100. When the feeder 10 is in operation, as parts move on the conveyor 40 from a position in the vicinity of the crowder landing member 80 and past the flex crowder member 90 to the singulator crowder member 100, any stacked parts and/or crowded parts (i.e. parts positioned side-by-side) are diverted back to the hopper 20 to be recycled through the process again.
[0027] The base concept of a step feeder is to align or singulate the parts such that the parts can then be fed either into a fixed escarpment or positioned in the field of view of a vision system associated with the step feeder. The conventional lift is of a fixed with and parts not aligned initially fall off the lift back into the hopper. With this type of system, the staging area is fixed so that as the parts move along the conveyor, they are further aligned. For large parts and/or cylindrical parts a wider lift is needed. The system of the present invention uses a different approach. All parts (i.e. small, large and/or cylindrical) are raised by a lift of defined width. The flex crowder staging or accumulation area 70, can be adjusted to a position either close to the edge of the conveyor 40 or set back from the edge of the conveyor 40. If a part being staged needs to be tipped back into the hopper 20, then the crowder landing member 80 can be moved forward close to the edge of the conveyor 40, in a similar manner to using a lift of narrow depthbut rather than have the parts tip back into the hopper 20 because the lift is too narrow to support them, in the case of the present invention, the parts tip back into the hopper 20 since the staging or accumulation area 70 has been narrowed by movement of the crowder landing member 80. In contrast, when larger parts are to be selected, since the lift is already of a fixed, wide depth to accommodate larger sized parts, the staging area 70 can be set wider by moving the crowder landing member 80 further away from the edge of the conveyor 40.
[0028] An angled destacker, shown generally by reference numeral 130 functions to deflect stacked parts while reducing the occurrence of parts jamming by variance of its pinch point angle. In the embodiment shown in
[0029] As mentioned, parts are singulated as they pass along the conveyor 40 from the area in the vicinity of the flex crowder member 90 to the area of the conveyor in the vicinity of the singulator crowder member 100. In the flex crowder 120 embodiment shown in
[0030] As different parts have different shapes, sizes, heights and centers of gravity, the push point or blow off point of a given part will vary from the upper surface of the conveyor 40 to typically the mid-point from the bottom of the conveyor to the top of the part. For example, parts such as washers which lie very close to the conveyor 40 surface require a low blow off point close to the conveyor 40 surface. In contrast, mid-size parts such as a inch nut may require a blow off point above the base of the conveyor 40. To accommodate a wide variety of parts of various shapes and sizes, heights and centers of gravity, a multiple blow off manifold with multiple jet outlet locations (or blowers 150) is used. Setting the location of the blow off point(s) is as simple as removing set screws from the manifold for desired location(s) and placing in set screws for blocking individual blowers 150.
[0031] Since parts on a conveyor may be prone to rolling (including cylindrical-shaped parts), the parts feeder 10 of the present invention may be adapted to slightly tilt the parts feeder (or the conveyor 40 portion of the parts feeder) to create a slight incline (e.g. 1 degree, or 1 to 5 degrees) on the conveyor 40 as parts move from the staging area 70 through the singulation crowder member 100 zone of the conveyor 40. This allows for cylindrical parts to be stabilized while traveling through the camera 180 field of view on the conveyor 40, while also not impeding the part from being rejected.
[0032] Now referring to
[0033] The part continues to move along the conveyor 40, wherein the position of the part has now been located by the laser trigger sensor to identify the leading-edge trigger set point and the position of the part on the conveyor based on the encoder count readings. The encoder count readings may be transmitted from the encoder for processing as part of a computer implemented system, wherein key components of the system are in network communication with one another in order to produce a set out outputs. A processor may be employed to receive and analyze the encoder count readings and transmit instructions to the camera 180 to take an image of the part when the part reaches the focal area for the camera 180, on the conveyor 40. A computer associated with a memory having stored thereon a database of existing part images, can be employed to receive a transmission of the image in question and compare the image in question to the images in the database using a proprietary algorithm based on input from the network linked camera, laser trigger sensor, and conveyor encoder for the purpose of identifying a non-compliant part. When a non-compliant part is identified, the system transmits instructions to a processor associated with the at least one blower 150 to activate and the at least one blower 150 or a combination of a plurality of blowers in order to remove the part from the conveyor 40.
[0034] In the case where a part is identical dimensionally to another part but only distinguishable by color, then the algorithm is set up to compare multiple (2 or more) images to determine a non-compliant part. When a part is identical to another with all physical dimensions and distinguishable only by color or finish, multiple camera images are then considered in the algorithm.
[0035] The part continues to move along the conveyor, the position is still being reference based on the pulse counts provided by the conveyor encoder. The part would then reach the part reject location or blow off. If the algorithm has determined that the part is non-compliant, then the blow-off pulse is activated. Typically, and by default the program is set up for a single reject/blow off pulse and is activated in, or approximately in, the center location of the part. In some cases, multiple blow off pulses will be required. The location of the blow off may be determined not to be the part center and may be activated ahead or after the center of the part which can be located by the leading edge of the laser trigger point as well as the location based on the pulse count from the encoder associated with the conveyor motor.
[0036] The algorithm monitors parts as they pass under the camera 180. If after a set period of time where parts are no longer being sensed as present, the system interprets this as a jam. At this point the conveyor stops, the lift is deactivated and the conveyor cycles in reverse to remove parts from the conveyor and from the destacker. Once the cycle concludes, normal operation resumes.
[0037] Consider the following jam clearing examples. The first is based on a situation where the destacker 130 cannot clear multiple level parts. In this case the conveyor 40 would continue to run however no images would be recorded by the camera 180. If after a set period of time (e.g. fifteen seconds), the system would assume a jam and go into a jam recovery cycle, wherein the conveyor motor 60 would move in a reverse direction. The lift motor 50 moves the lift to a lower position and remains there for the cycle, and any parts jammed under the destacker 130 would travel back to the conveyor landing area adjacent to member 80 and be directed back into the hopper 20. While the conveyor 40 reverses the blow off pulses of the at least one blower 150, any parts that are on the discharge member of the conveyor are returned back into the hopper 20 to be recycled. If the jam has cleared, the parts traveling along the conveyor 40 will now trigger an escapement sensor 170 which would reset a jam cycle count to zero. If a jam is still present a jam cycle count would increase by one and the jam recovery cycle would repeat. This cycle will repeat for three times or until the jam cycle count reaches three. If after the third time a jam is still being detected, the system will shut down a wait for technically assistance. The system will not restart until the system is reset. The escapement sensor 170 functions to monitor parts as they are being discharged through the escapement (e.g. the end of the conveyor 40, or conveyor roll-off member). If the escapement sensor 170 remains activated typically for a period of fifteen seconds, if is considered that there is an issue at the discharge of the parts. This would not be considered a feeder problem but to moderate the feeder, the conveyor motor 60 and the lift motor 50 would stop until the issue is resolved and parts resume feeding.
[0038] At some point the current part being run requires a change over to a new part. When this happens, the hopper 20 may be empty, partially full or completely full. Feeders are typically emptied by either scooping or manually picking the parts out or by continuing to run the system and switching a form of gate mechanism. At times this gate mechanism is not easily or safely accessible. The feeder 10 of the present invention uses an empty hopper cycle, wherein a back gate 190 is removed and an empty bin cycle is initiated which has the lift 30 operate as normal but in this case the conveyor 40 is reversed. The parts are then discharged to an area which is typically not the production member. The feeder allows for a hopper empty cycle by opening the back gate 190 and reversing the conveyor 40 while the lift 30 continues to cycle.
[0039] The scope of this disclosure encompasses all changes, substitutions, variations, alterations, and modifications to the example embodiments described or illustrated herein that a person having ordinary skill in the art would comprehend. The scope of this disclosure is not limited to the example embodiments described or illustrated herein. Moreover, although this disclosure describes and illustrates respective embodiments herein as including particular components, elements, functions, operations, or steps, any of these embodiments may include any modification, combination or permutation of any of the components, elements, functions, operations, or steps described or illustrated anywhere herein that a person having ordinary skill in the art would comprehend. All such modifications, combinations and permutations are believed to be within the sphere and scope of the invention as defined by the claims appended hereto.