WO2022151178A1

WO2022151178A1 - Apparatus and method for feeding flexible ring-shaped workpieces

Info

Publication number: WO2022151178A1
Application number: PCT/CN2021/071813
Authority: WO
Inventors: Zhiwei Li; Qi Lu
Original assignee: Abb Schweiz Ag
Priority date: 2021-01-14
Filing date: 2021-01-14
Publication date: 2022-07-21
Also published as: CN116529028A

Abstract

An apparatus and method for feeding flexible ring-shaped workpieces. The apparatus comprises a feeder (101) adapted to separate at least one workpiece (201) from a pile of workpieces (201) to a predetermined location by vibration; an identifying assembly (102) adapted to acquire and analyze an image of the at least one workpiece (201) on the predetermined location to identify an operation position of a selected workpiece; and an operating assembly (103) adapted to be coupled to the selected workpiece (201) at the operation position to feed the selected workpiece (201) to a standby location. With the apparatus, a selected flexible ring-shaped workpiece such as a belt can be, without manual operation of the workpiece, separated from a pile of workpieces and automatically fed to a standby location. In this way, the flexible ring-shaped workpieces can be fed faster and more accurately.

Description

APPARATUS AND METHOD FOR FEEDING FLEXIBLE RING-SHAPED WORKPIECES

FIELD

Embodiments of the present disclosure generally relate to an apparatus and a method for feeding flexible ring-shaped workpieces.

BACKGROUND

Flexible ring-shaped workpieces are typically used on a device for purposes such as transmission, sealing, or the like. Common flexible ring-shaped workpieces comprise belts such as V-belts, circular belts, timing belts (also known as toothed belts) , etc., and O-rings. The belts, which are typically used on vehicle engines, industrial robots, home appliances or the like, aim to transmit power from a driving part to a driven part. The O-rings provide sealing between two parts.

For some relatively “rigid” O-rings, due to their small diameter-to-width ratio, they are usually less prone to deformation or relatively controllable deformation in comparison with belts which are relatively “flexible” due to large diameter-to-width ratio. Some approaches have been proposed to feed and even to assemble the relatively “rigid” O-rings. These approaches at least partially take advantage of “rigid” characteristics of the relatively “rigid” O-rings, and therefore may not be suitable for relatively “flexible” belt-type components.

Actually, due to its ring shape and flexibility and elasticity, a relatively “flexible” belt tends to entangle with other belts when in a hopper. As a result, it is difficult for a robot to position and grip the flexible belt, let alone to assemble it to a predetermined position of a device. Therefore, as for some relatively flexible ring-shaped workpieces such as belts, it is usually manually fed and assembled to the proper position of a device.

SUMMARY

Embodiments of the present disclosure provide an apparatus for feeding flexible ring-shaped workpieces.

In a first aspect, an apparatus for feeding flexible ring-shaped workpieces is provided. The apparatus comprises a feeder adapted to separate at least one workpiece from a pile of workpieces to a predetermined location by vibration; an identifying assembly adapted to acquire and analyze an image of the at least one workpiece on the predetermined location to identify an operation position of a selected workpiece; and an operating assembly adapted to be coupled to the selected workpiece at the operation position to feed the selected workpiece to a standby location.

With the apparatus according to embodiments of the present disclosure, a selected flexible ring-shaped workpiece such as a belt can be, without manual operation of the workpiece, separated from a pile of workpieces and automatically fed to a standby location. In this way, the flexible ring-shaped workpieces can be fed faster and more accurately.

In some embodiments, the feeder comprises a hopper arranged obliquely on and driven by a vibrator and adapted to receive the pile of workpieces, the hopper comprising an outlet arranged at a lower position of the hopper; and a baffle arranged at the outlet so that the outlet has a height larger than a height of the workpiece to allow the at least one workpiece to be discharged from and separated by the outlet. In this way, the workpieces that are entangled together can be effectively separated through the outlet, so that at least one workpiece released from the outlet is basically not entangled. As a result, the reliability of the apparatus is further improved.

In some embodiments, the hopper is arranged above the predetermined location so that a distance between the outlet and the predetermined location is larger than or equal to a length of a long axis of the workpiece after being deformed. This arrangement may ensure that the at least one workpiece can be dropped to the predetermined location, thereby further improving the reliability of the apparatus.

In some embodiments, the identifying assembly comprises: a camera arranged over the predetermined location to acquire the image of the at least one workpiece on the predetermined location; and a controller adapted to: determine a selected edge of the at least one workpiece in the image; determine a minimum distance between a position of the selected edge and a corresponding adjacent edge of the at least one workpiece; and determine the position of the selected edge as the operation position in response to the minimum distance being larger than or equal to a predetermined value. In this way, the operation position can be identified in a simple way.

In some embodiments, the identifying assembly further comprises a frame arranged across the predetermined location; and a supporter arranged on the frame to support the camera. This arrangement enables the apparatus to be manufactured more easily and increases the flexibility of the apparatus.

In some embodiments, the operating assembly comprises a gripper coupled to a robot to grip the selected workpiece at the operation position. With this arrangement, the selected workpiece can be fed more easily.

In some embodiments, the identifying assembly is further adapted to determine a gripping direction along which the gripper grips the selected workpiece, the gripping direction perpendicular to a tangent direction of the selected edge at the operation position. As a result, it is ensured that the selected workpiece can be firmly gripped.

In some embodiments, the operating assembly comprises a push rod coupled to a robot to push the selected workpiece radially outward at the operation position. In this way, the selected workpiece can be fed to the standby location with the operating assembly having simplified structures.

In some embodiments, the apparatus further comprises at least one wall comprising a notch to allow the selected workpiece pushed by the push rod to pass through. This arrangement can ensure that only one selected workpiece is fed to the standby location, thereby further improving the reliability of the apparatus.

In some embodiments, the apparatus further comprises a push plate arranged to push the at least one workpiece to ensure that the at least one workpiece is in the predetermined location. The push plate can ensure that the at least one workpiece release from the hopper is in the predetermined location.

In some embodiments, the apparatus further comprises a shaping plate arranged at the standby location and adapted to shape a part of the selected workpiece to a predetermined shape. This further facilitates the further operation of the selected workpiece, for example assembling of the workpiece to a device. The applicability of the apparatus is improved.

In some embodiments, the identifying assembly is further adapted to determine a reference point located inside the selected workpiece relative to the operation position. This arrangement can ensure the selected workpiece is fed into a shaping plate to facilitate the further operation of the selected workpiece.

In some embodiments, the shaping plate is U-shaped or V-shaped or comprises two edges separated by a predetermined distance. This allows the shaping plate to be manufactured more flexibly.

In a second aspect, a method of feeding flexible ring-shaped workpieces is provided. The method comprises causing at least one workpiece to be separated from a pile of workpieces to a predetermined location by vibration; identifying an operation position of a selected workpiece by analyzing an image of the at least one workpiece on the predetermined location; and causing an operating assembly to couple to the selected workpiece at the operation position to feed the selected workpiece to a standby location.

In some embodiments, identifying the operation position of the selected workpiece comprises determining a selected edge of the at least one workpiece in the image; determining a minimum distance between a position of the selected edge and a corresponding adjacent edge of the at least one workpiece; and determining the position of the selected edge as the operation position in response to the minimum distance being larger than or equal to a predetermined value.

In some embodiments, the method further comprises determining a gripping direction perpendicular to a tangent direction of the selected edge at the operation position; and causing the selected workpiece to be gripped along the gripping direction.

In some embodiments, the method further comprises determining a reference point located inside the selected workpiece relative to the operation position; and causing the selected workpiece to be coupled with the operating assembly by means of the reference point.

It is to be understood that the Summary is not intended to identify key or essential features of embodiments of the present disclosure, nor is it intended to be used to limit the scope of the present disclosure. Other features of the present disclosure will become easily comprehensible through the description below.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objectives, features and advantages of the present disclosure will become more apparent through more detailed depiction of example embodiments of the present disclosure in conjunction with the accompanying drawings, wherein in the example embodiments of the present disclosure, same reference numerals usually represent the same components.

FIG. 1 shows a front view and a side view of a flexible ring-shaped workpiece;

FIG. 2 shows a simplified perspective view of an apparatus according to embodiments of the present disclosure;

FIG. 3 shows a perspective view of a feeder of an apparatus according to embodiments of the present disclosure; and

FIG. 4 shows a simplified perspective view of an apparatus according to embodiments of the present disclosure;

FIG. 5 shows a perspective view of an operating assembly of an apparatus when operating a selected workpiece according to embodiments of the present disclosure;

FIG. 6 shows a perspective view of an operating assembly when pushing a selected workpiece into a shaping plate according to embodiments of the present disclosure;

FIG. 7 shows a perspective view of a shaping plate with a workpiece arranged therein according to embodiments of the present disclosure; and

FIG. 8 shows a flowchart illustrating a method of feeding flexible ring-shaped workpieces according to embodiments of the present disclosure.

Throughout the drawings, the same or similar reference symbols are used to indicate the same or similar elements.

DETAILED DESCRIPTION

The present disclosure will now be discussed with reference to several example embodiments. It is to be understood these embodiments are discussed only for the purpose of enabling those skilled persons in the art to better understand and thus implement the present disclosure, rather than suggesting any limitations on the scope of the subject matter.

As used herein, the term “comprises” and its variants are to be read as open terms that mean “comprises, but is not limited to. ” The term “based on” is to be read as “based at least in part on. ” The term “one embodiment” and “an embodiment” are to be read as “at least one embodiment. ” The term “another embodiment” is to be read as “at least one other embodiment. ” The terms “first, ” “second, ” and the like may refer to different or same objects. Other definitions, explicit and implicit, may be comprised below. A definition of a term is consistent throughout the description unless the context clearly indicates otherwise.

Flexible ring-shaped workpieces, such as belts or O-rings, are essential parts for power transmission and sealing, or the like in the automotive, robotics, and home appliances, etc. There are many sizes of flexible ring-shaped workpieces used in the industry. FIG. 1 shows a front view and a side view of a flexible ring-shaped workpiece. As shown, the flexible ring-shaped workpiece with certain elasticity has a wire diameter W (referred to as a width) , an inner diameter I (referred to as a diameter) and a height T in an axial direction. Generally, a ratio of the diameter I to the width W (referred to as diameter-to-width ratio) may reflect the deformation ability of the flexible ring-shaped workpiece to a certain extent. Specifically, the smaller the ratio, the harder it is to be deformed and the larger the ratio, the more easy it is to be deformed.

In a case where the diameter-to-width ratio of a flexible ring-shaped workpiece is larger than a certain threshold, it is usually easy to be deformed and entangled with other workpieces, and as a result, it is basically impossible to separate and feed a messy pile of flexible ring-shaped workpieces with the conventional feeding apparatus and method. Thus, in many cases, flexible ring-shaped workpieces need to be separated or fed manually. Manual operation is inefficient and labor-intensive which significantly reduces the overall assembly efficiency of a device using the flexible ring-shaped workpieces. Furthermore, manual separation and feeding of the flexible ring-shaped workpieces are also prone to maloperations and various assembly problems.

In order to improve efficiency and accuracy, embodiments of the present disclosure provide an apparatus for feeding flexible ring-shaped workpieces. Now some example embodiments will be described with reference to FIGs. 2-7. A belt such as a timing belt, which is widely used in the field, will be mainly used as an example of the flexible ring-shaped workpiece to describe the concept of the present disclosure in the following. It is to be understood that this is merely illustrative and is not intended to limit the scope of the present disclosure. Any other suitable flexible ring-shaped workpieces 201, such as O-rings or the like, may also be automatically separated and fed using the apparatus according to embodiments of the present disclosure without human intervention, which will be not repeated in the following.

FIG. 2 shows a simplified perspective view of an apparatus 100 according to embodiments of the present disclosure. As shown, generally, the apparatus 100 for feeding flexible ring-shaped workpieces 201 (also referred to as workpieces 201 in the following) comprises a feeder 101, an identifying assembly 102 and an operating assembly 103. The operating assembly 103 may be a part of or arranged on an end effector of a robot (not shown) . As shown in FIG. 2, in the feeder 101, a pile of workpieces 201 are entangled or overlapping with each other. Usually, it is difficult for a manipulator or a robot to automatically select or separate a workpiece 201 directly from the pile of workpieces 201 and to feed it to a standby location. To facilitate the automatic separation and feeding of the workpieces 201, the feeder 101 is adapted to separate at least one workpiece 201 from a pile of workpieces 201 to a predetermined location by vibration.

In some embodiments, the identifying assembly 102 can detect whether there are one or more workpieces 201 in the predetermined location. In response to a detection of whether there is one or more workpieces 201 in the predetermined location, the feeder’s vibration will stop until the identifying assembly 102 detects that there is no workpiece at the predetermined location again. Of course, it is to be understood that the vibration of the feeder can also be started or stopped by other trigger conditions. As shown in FIG. 2, at the predetermined location, four workpieces 201 have been separated from the pile of workpieces 201. The number of workpieces dropped by vibration from the feeder 101 is related to the detection interval, a size of an outlet and inclination angle of the feeder 101, etc., and it is to be understood that the smaller the number, the higher the processing efficiency. Thus, to improve the processing efficiency, the above parameters, such as a size of an outlet and inclination angle of the feeder 101, etc., are set reasonably so that the number of dropped workpieces is controlled within a reasonable range, e.g., from 1 to 5.

The feeder 101 can separate the at least one workpiece 201 from the pile of workpieces 201 in any suitable way. For example, in some embodiments, as shown in FIGs. 1 and 2, the feeder 101 may comprise a hopper 1012 and a baffle 1014. The hopper 1012 is used to receive the pile of workpieces 201 and is arranged obliquely with an outlet 1013 arranged at a lower position. The hopper 1012 is driven by a vibrator to vibrate. The tilting angle of the hopper 1012 is set to allow the workpieces 201 arranged therein to slide effectively at an appreciated speed when it vibrates. For example, in some embodiments, the tilting angle may range from 15° to 30°. In addition to the tilting angle, in order to achieve effective sliding of the workpieces 201 during vibration, the inner bottom surface of the hopper 1012 is sufficiently smooth.

FIGs. 1 and 2 show that in some embodiments, a pneumatic vibrator is used to provide vertical vibration. The pneumatic vibrator is connected with the air pressure source to realize low-frequency and large-amplitude vibration, which is beneficial to effectively separating the workpieces 201. It is to be understood that the above embodiments where the vibrator is the pneumatic vibrator are merely illustrative, without suggesting any limitation as to the scope of the present disclosure. The vibrator may be any suitable component that can provide appropriate vibration (including vertical vibration, horizontal vibration or a combination of both) of the hopper 1012. For example, in some alternative embodiments, the vibrator may comprise a motor and an eccentric wheel to provide the vibration.

With the vibration of the hopper 1012, the workpieces 201 will slide to and eventually be discharged from the outlet 1013 located at the lower position of the hopper 1012. To prevent the workpieces 201 entangled together from being discharged from the outlet 1013, the baffle 1014 is arranged at the outlet 1013 so that the outlet 1013 has a height only allowing the workpieces 201 which are not entangled or overlapping to pass through. The upper workpieces of the overlapping or entangled workpieces will be blocked by the baffle 1014 to achieve the purpose of separation. As a result, the entangled workpieces 201 can only be discharged from the outlet 1013 after being separated. In some embodiments, as shown in FIG. 3, the height H of the outlet 1013 limited by the baffle 1014 may be larger than the height T of the workpiece 201. For example, according to factors such as the amplitude of vibration, the height H of the outlet 1013 may range from 1 to 3 times, e.g., 1, 1.1, 1.2, 1.3, 1.5, 2, 2.5 times, the height T of the workpiece 201. In this way, the feeder 101 ensures that the at least one workpiece 201 discharged from the feeder 101 is not entangled, which is beneficial for subsequent identification and operation of the workpieces 201.

Furthermore, as shown in FIGs. 1 and 2, there is a distance (i.e., a height difference) between the outlet 1013 of the hopper 1012 and the predetermined location. The workpieces 201 discharged from the outlet 1013 will fall in the predetermined location. When falling, the workpiece 201 would probably fall with a long axis thereof as a substantially vertical orientation. To prevent the workpieces 201 from hanging at the outlet 1013 and not falling on the predetermined location, the height difference between the outlet 1013 and the predetermined location is larger than or at least equal to a length of a long axis of the workpiece 201 after being deformed. This arrangement ensures that the workpieces 201 discharged from the outlet 1013 can drop on the predetermined location.

It can be seen from the above that with the hopper 1012 for receiving the pile of workpieces 201 and the baffle 1014 to limit the height of the outlet 1013, the workpieces 201 may be effectively separated and discharged to the predetermined location with simple structures. It is to be understood that the feeder 101 as described in the above embodiments is merely illustrative, without suggesting any limitations as to the scope of the present disclosure. Any other suitable structures and/or arrangements are possible as well. For example, in some alternative embodiments, the feeder 101 may also comprise a combination of a vibrating conveyor and a baffle 1014.

After the workpieces 201 drop on the predetermined location, to ensure that the operating assembly 103 can operate one workpiece 201 (referred to as a selected workpiece 201) to a standby location, the identifying assembly 102 is adapted to acquire and analyze an image of the workpiece 201 on the predetermined location to identify an operation position of the selected workpiece 201. The standby location as mentioned above is a general term for locations that are conducive to following processes of flexible ring-shaped workpieces 201, such as shaping, assembling or the like.

The operation position at which the selected workpiece 201 is gripped may be located at any suitable edge (referred to as a selected edge) of the at least one workpiece 201 on the predetermined location. To prevent the operating assembly 103 from interfering with other workpieces during the gripping, in determination of the operation position, a minimum distance between a position of the selected edge and a corresponding adjacent edge of the at least one workpiece 201 may be determined. In some embodiments, if the minimum distance is larger than or equal to a predetermined value, then the position of the selected edge where the minimum distance is determined may be determined as the operation position.

To prevent the operating assembly 103 from feeding more than one workpiece 201 at once, the inventors have discovered that an operation position of the selected workpiece 201 for operating the selected workpiece 201 is preferably located at an outer boundary of the at least one workpiece 201 on the predetermined location. The outer boundary refers to a continuous closed line formed by outermost parts of the edge of at least one workpiece 201 on the predetermined location. Otherwise, if the operation position is located at any inner edges of the at least one workpiece 201 there is a risk of one or more workpieces being caught on the gripped workpiece 201 and being grabbed together. In the following, the concept of the present disclosure will be described mainly by taking the outer boundary as the selected edge as an example. It is to be understood that other edges except the outer boundary are also possible as the selected edge, and will not be described separately in the following.

In some embodiments, the identifying assembly 102 may comprise a camera 1021 arranged over the predetermined location to acquire the image of the at least one workpiece 201 on the predetermined location. In some embodiments, the identifying assembly 102 may further comprise a frame 1022 arranged across the predetermined location and a supporter 1023 moveably arranged on the frame 1022 to support the camera 1021, as shown in FIG. 1.

The movement of the supporter 1023 enables the camera 1021 to acquire an image of the at least one workpiece 201 at the predetermined location more flexibly. For example, in some embodiments, if the workpieces 201 at the predetermined location deviate from a viewing area of the camera 1021, the supporter 1023 for supporting the camera 1021 can be moved or deflected to align the viewing area with these workpieces 201.

It is to be understood that the above embodiments where the frame 1022 and moveable supporter 1023 are provided are merely illustrative, without suggesting any limitation as to the scope of the present disclosure. Any other suitable structure and/or arrangement are also possible. For example, in some alternative embodiments, the frame 1022 and the supporter 1023 may also be fixed and there are some additional arrangements to prevent the viewing area of the camera 1021 from being blocked by, e.g., the hopper 1012 or deviating from the predetermined location.

For example, in some alternative embodiments, the apparatus 100 may further comprise a push plate 105. The push plate 105 may be driven by suitable driving components such as a motor or a cylinder to move in a direction of the double arrow as shown in FIG. 4. If a part of the at least one workpiece 201 is blocked by the hopper 1012 or located outside of the predetermined location which is already aligned with the viewing area of the camera 1021, the push plate 105 can push the workpiece 201 to ensure that the at least one workpiece 201 is in the predetermined location and not blocked by the hopper 1012. In this way, the reliability of the apparatus 100 is improved.

With the acquirement of the image of the at least one workpiece 201, the identifying assembly 102 can analyze the image and identify the operation position of the selected workpiece 201 from the outer boundary of the at least one workpiece 201. This may be achieved by a controller of the identifying assembly 102. In some embodiments, the controller of the identifying assembly 102 may be a separated component from a controller of the robot which may be used to operate the operating assembly 103. In some alternative embodiments, the controller of the identifying assembly 102 may also be integrated into the controller of the robot. That is, in some embodiments, it is the controller of the robot to analyze the image and identify the operation position.

The controller can identify the operation position with an appropriate algorithm or method. For example, in some embodiments, the controller is adapted to first determine the outer boundary of the at least one workpiece 201 in the image, which can be achieved with any suitable algorithm. After the outer boundary is determined, a minimum distance between a position of the outer boundary and a corresponding adjacent inner edge of the workpiece 201 may be determined. In response to the minimum distance being larger than or equal to a predetermined value, the position of the outer boundary where the minimum distance is determined will be determined as the operation position. The predetermined value may be larger than a width of the operating assembly 103 for operating the selected workpiece 201, which ensures that the operating assembly 103 will not interfere with other workpieces 201 during the operation of the selected workpiece 201. In this way, the operation position may be automatically identified without human intervention.

It is to be understood that the above embodiments where the operation position is identified are merely illustrative, without suggesting any limitation as to the scope of the present disclosure. Any other suitable methods or approaches are also possible. For example, in some embodiments, alternatively or additionally, regions densely populated with several junction points may be recognized and transmitted into one-pixel to improve the algorithm accuracy and efficiency

It is also to be understood that the above embodiments regarding the operation position located at the outer boundary are merely for illustrative, without suggesting any limitation as to the scope of the present application. It is also possible that the operating position is one the inner edges of the at least workpiece 201. For example, in some embodiments where there are other technologies or algorithms that can prevent the above mentioned risk of one or more workpieces being caught on the gripped workpiece 201 or of the overlapping edges being gripped, the operation position may also be at any suitable position of any edge of the at least workpiece 201.

With the operation position of the selected workpiece 201 being identified, the operating assembly 103 will be then controlled, e.g., by the robot as mentioned above, to be coupled to the selected workpiece 201 at the operation position to feed the selected workpiece 201 to the standby location. In some embodiments, as shown in FIG. 5, the operating assembly 103 may comprise a gripper 1031 coupled to the robot. The gripper 1031 may comprise at least two gripping members that can be move towards or away from each other to grip or release the selected workpiece 201.

To increase a success rate of gripping and reduce a required stroke of the gripping members, in some embodiments, a gripping direction along which the gripping members are moved may be determined. In some embodiments, the gripping direction may be perpendicular to a tangent direction of the selected edge, such as the outer boundary, at the operation position. For example, after the operation position is identified, the controller can then determine the tangent direction of the selected edge at the operation position. Subsequently, a direction perpendicular to the tangent direction can then be determined as the gripping direction to ensure that the workpiece 201 can be gripped radially instead of circumferentially at the operation position, thereby further improving the reliability of the apparatus 100.

It is to be understood that the above embodiments where the selected workpiece 201 is operated by the gripper 1031 are merely illustrative, without suggesting any limitation as to the scope of the present disclosure. Any other suitable structures and/or arrangements are also possible. For example, in some alternative embodiments, the operating assembly 103 may comprise a push rod 1032 coupled to the robot, as shown in FIG. 4.

Instead of gripping, the push rod 1032 can push the selected workpiece 201 radially outward at the operation position. In this way, the workpiece 201 can be fed with simple structures. In some embodiments, the push rod 1032 may also be formed by moving the gripping members of the gripper 1031 as mentioned above close to each other. That is, in a case where the gripper 1031 is provided, the selected workpiece 201 can be either gripped or pushed by the gripper 1031. In some alternative embodiments, the push rod 1032 may also be a separated component from the gripper 1031, to further simplify structures of the operating assembly 103.

To ensure that the selected workpiece 201 is pushed by the push rod 1032 from the inside to the outside thereof, in some embodiments, a reference point located inside the selected workpiece 201 relative to the operation position may be determined. For example, in some embodiments, after the operation position is determined, the reference point indicating the inside of the selected workpiece 201 may then be determined. Then the push rod 1032 may be operated to move over the reference point or a point adjacent to the reference point. Subsequently, the push rod 1032 is moved vertically down so that a distance between a free end of the push rod 1032 and a plane for arranging the selected workpiece 201 is smaller than the height T of the workpiece 201. In this way, with the further movement of the push rod 1032 towards the operation position, the selected workpiece 201 will be pushed or dragged by the push rod 1032.

To prevent other workpieces 201 than the selected workpiece 201 from being dragged to the standby location by the selected workpiece 201 during the process of the push rod 1032 pushing the selected workpiece 201, in some embodiments, as shown in FIG. 4, at least one wall 104 with a notch 1041 may be provided. The notch 1041 has a width larger than or equal to a minimum curvature diameter of a workpiece 201 after being deformed. Furthermore, as mentioned above, the width of the notch 1041 is also set to prevent other workpieces 201 than the selected workpiece 201 from being dragged through the notch 1041. To this end, in some embodiments, the width of the notch 1041 may be smaller than two or three times the minimum curvature diameter. In this way, only the selected workpiece 201 can be pushed to pass through the notch 1041. Other workpieces 201 that may be dragged by the selected workpiece 201 are blocked by the wall 104.

Relative to the predetermined location, the standby location is located outside the wall 104. After passing through the notch 1041, the selected workpiece 201 will continue to be pushed to the standby location. In some embodiments, at the standby location, a shaping plate 106 may be provided. The shaping plate 106 can be used to shape a part of the selected workpiece 201 to a predetermined shape, as shown in FIGs. 6 and 7.

In some embodiments, the shaping plate 106 may comprise two edges separated by a predetermined distance. The predetermined distance may be related to a diameter of a part of a device in which the workpiece 201 is to be assembled. For example, in some embodiments where the device, such as a joint of a robot, has a more compact size, the predetermined distance may be slightly smaller than the diameter of the part of the device in which the workpiece 201 is to be assembled. In some alternative embodiments, the predetermined distance may be slightly larger than the diameter of the part of the device. After the selected workpiece 201 is pushed or gripped to a position adjacent to the shaping plate 106, the selected workpiece 201 will be pushed further along a direction of an arrow as shown in FIG. 6, which is substantially parallel to the edges, as shown in FIG. 6.

When the selected workpiece 201 is moved between the two edges, the two edges will force the part of the selected workpiece 201 between the two edges to be deformed and eventually cause the entire workpiece 201 to be deformed, as shown in FIG. 7. The deformed workpiece 201 will be further operated, e.g., to be assembled on the device where the workpiece 201 is needed.

It is to be understood that the above embodiments where the shaping plate 106 comprises two edges are merely illustrative, without suggesting any limitation as to the scope of the present disclosure. Any other suitable structures and/or arrangements are also possible. For example, in some alternative embodiments, the shaping plate 106 may also be U-shaped or V-shaped.

After the selected workpiece 201 has been assembled in the device, the identifying assembly 102 will be operated further to identify an operation position of a next selected workpiece 201 from a new selected edge formed by the remaining workpiece (s) 201 on the predetermined location. The above mentioned gripping or pushing of the selected workpiece 201 will be repeated, until no workpiece 201 is located on the predetermined location.

When no workpiece 201 is located on the predetermined location, the feeder 101 may then be operated to separate a next batch of workpieces 201 from the remaining workpieces 201 in the hopper 1012, until the number of the workpieces 201 in the hopper 1012 is smaller than a predetermined value or equal to zero. Then the next pile of workpieces 201 may be provided in the hopper 1012 for further operation.

It can be seen from the above that with the apparatus 100 according to embodiments of the present disclosure, a selected flexible ring-shaped workpiece 201 such as a belt can be, without human intervention, separated from a pile of workpieces 201 and automatically fed to a standby location. In this way, the flexible ring-shaped workpieces 201 can be fed faster and more accurately.

According to other aspects of the present disclosure, a method of feeding flexible ring-shaped workpieces 201 is provided. FIG. 8 shows a flowchart illustrating a method of feeding flexible ring-shaped workpieces 201 according to embodiments of the present disclosure. The method can be implemented as program codes stored in a memory, which can be performed by a controller of a robot or any other suitable controller or processor.

At block 410, the controller causes the at least one workpiece 201 to be separated from a pile of workpieces 201 to a predetermined location by vibration, which may be performed by the feeder 101 as mentioned above. After the at least one workpiece 201 is separated and located on the predetermined location, at block 420, the controller identifies an operation position of a selected workpiece 201 from a selected edge, such as an outer boundary, of the at least one workpiece 201 by analyzing an image of the at least one workpiece 201 on the predetermined location, which is acquired by the identifying assembly 102 as mentioned above. After the operation position is identified, at block 430, the controller causes an operating assembly 103 to couple to, e.g., to grip or push or the like, the selected workpiece 201 at the operation location. In this way, the selected workpiece 201 can be fed to a standby location.

At the standby location, as mentioned above, the selected workpiece 201 or at least a part thereof may be shaped to facilitate the further operations. After the selected workpiece 201 is removed from the standby location for further operation, the steps as shown in

blocks

420 and 430 may be repeated until there is no workpiece 201 located on the predetermined location. Then the step as shown in the block 410 may be repeated. In this way, workpieces 201 arranged in piles may be fed to the standby location for further operation automatically without human intervention. The efficiency and accuracy for feeding the flexible ring-shaped workpieces 201 can be significantly improved.

In some embodiments, to identify the operation position of the selected workpiece 201, the controller may determine the selected edge, such as the outer boundary, of the at least one workpiece 201 in the image. After that, a minimum distance between a position of the selected edge and a corresponding adjacent edge of the at least one workpiece 201 may be determined. In response to the minimum distance being larger than or equal to a predetermined value, the position of the selected edge where the minimum distance is determined may be determined as the operation position.

In some embodiments, the controller may also determine a gripping direction perpendicular to a tangent direction of the selected edge at the operation position. In this way, the selected workpiece 201 can be gripped for example by the gripper 1031 as mentioned above along the gripping direction. In this way, the selected workpiece 201 can be gripped radially, which reduces the stroke of the gripper 1031 and thus reduces a size of a driving component such as an air cylinder for driving the gripper 1031. In this way, the costs of the gripper 1031 can be reduced.

In some embodiments, the controller may also determine a reference point located inside the selected workpiece relative to the operation position. On the one hand, this allows the operating assembly 103 such as the push rod 1032 to move into a position that can be coupled with the workpiece 201 by means of the reference point. On the other hand, it can be ensured that the selected workpiece 201 can be pushed into the shaping plate 106. In this way, the reliability of the apparatus 100 can be significantly improved.

It should be appreciated that the above detailed embodiments of the present disclosure are only for exemplifying or explaining principles of the present disclosure and do not limit the present disclosure. Therefore, any modifications, equivalent alternatives and improvements, etc. without departing from the spirit and scope of the present disclosure shall be comprised in the scope of protection of the present disclosure. Meanwhile, appended claims of the present disclosure aim to cover all the variations and modifications falling under the scope and boundary of the claims or equivalents of the scope and boundary.

Claims

An apparatus for feeding flexible ring-shaped workpieces (201) , comprising:

a feeder (101) adapted to separate at least one workpiece (201) from a pile of workpieces (201) to a predetermined location by vibration;

an identifying assembly (102) adapted to acquire and analyze an image of the at least one workpiece (201) on the predetermined location to identify an operation position of a selected workpiece; and

an operating assembly (103) adapted to be coupled to the selected workpiece (201) at the operation position to feed the selected workpiece (201) to a standby location.
The apparatus of claim 1, wherein the feeder (101) comprises:

a hopper (1012) arranged obliquely on and driven by a vibrator (1011) and adapted to receive the pile of workpieces (201) , the hopper (1012) comprising an outlet (1013) arranged at a lower position of the hopper (1012) ; and

a baffle (1014) arranged at the outlet (1013) so that the outlet (1013) has a height (H) larger than a height (T) of the workpiece (201) to allow the at least one workpiece (201) to be discharged from and separated by the outlet (1013) .
The apparatus of claim 2, wherein the hopper (1012) is arranged above the predetermined location so that a distance between the outlet (1013) and the predetermined location is larger than or equal to a length of a long axis of the workpiece (201) after being deformed.
The apparatus of claim 1, wherein the identifying assembly (102) comprises:

a camera (1021) arranged over the predetermined location to acquire the image of the at least one workpiece (201) on the predetermined location; and

a controller adapted to:

determine a selected edge of the at least one workpiece (201) in the image;

determine a minimum distance between a position of the selected edge and a corresponding adjacent edge of the at least one workpiece (201) ; and

determine the position of the selected edge as the operation position in response to the minimum distance being larger than or equal to a predetermined value.
The apparatus of claim 4, wherein the identifying assembly (102) further comprises:

a frame (1022) arranged across the predetermined location; and

a supporter (1023) arranged on the frame (1022) to support the camera (1021) .
The apparatus of claim 1, wherein the operating assembly (103) comprises:

a gripper (1031) coupled to a robot to grip the selected workpiece (201) at the operation position.
The apparatus of claim 6, wherein the identifying assembly (102) is further adapted to determine a gripping direction along which the gripper (1031) grips the selected workpiece (201) , the gripping direction perpendicular to a tangent direction of the selected edge at the operation position.
The apparatus of claim 1, wherein the operating assembly (103) comprises:

a push rod (1032) coupled to a robot to push the selected workpiece (201) radially outward at the operation position.
The apparatus of claim 8, further comprising:

at least one wall (104) comprising a notch (1041) to allow the selected workpiece (201) pushed by the push rod (1032) to pass through.
The apparatus of any of claims 1-9, further comprising:

a push plate (105) arranged to push the at least one workpiece (201) to ensure that the at least one workpiece (201) is in the predetermined location.
The apparatus of any of claims 1-9, further comprising:

a shaping plate (106) arranged at the standby location and adapted to shape a part of the selected workpiece (201) to a predetermined shape.
The apparatus of claim 11, wherein the identifying assembly (102) is further adapted to determine a reference point located inside the selected workpiece (201) relative to the operation position.
The apparatus of claim 11, wherein the shaping plate is U-shaped or V-shaped or comprises two edges separated by a predetermined distance.
A method of feeding flexible ring-shaped workpieces (201) , comprising:

causing at least one workpiece (201) to be separated from a pile of workpieces (201) to a predetermined location by vibration;

identifying an operation position of a selected workpiece by analyzing an image of the at least one workpiece (201) on the predetermined location; and

causing an operating assembly (103) to couple to the selected workpiece (201) at the operation position to feed the selected workpiece (201) to a standby location.
The method of claim 14, wherein identifying the operation position of the selected workpiece comprises:

determining a selected edge of the at least one workpiece (201) in the image;

determining a minimum distance between a position of the selected edge and a corresponding adjacent edge of the at least one workpiece (201) ; and

determining the position of the selected edge as the operation position in response to the minimum distance being larger than or equal to a predetermined value.
The method of claim 14, further comprising:

determining a gripping direction perpendicular to a tangent direction of the selected edge at the operation position; and

causing the selected workpiece (201) to be gripped along the gripping direction.
The method of any of claims 14-16, further comprising:

determining a reference point located inside the selected workpiece relative to the operation position; and

causing the selected workpiece (201) to be coupled with the operating assembly by means of the reference point into a shaping plate.