Patent Description:
This disclosure is directed generally at transporting parts in/on an assembly line, and at a method and apparatus for part transfer and transport when moving a group or matrix of parts on a first conveyor system to a second conveyor system in which the parts have a different configuration.

In part transfer and transport systems, parts are typically moved around by conveyors and then acted on at various stations along an assembly line. In some cases, a conveyor will feed a part or parts to a station, a process may be performed on the part or parts, and then a second conveyor will move the part or parts away from the station. In some cases, a group/matrix of parts may enter a station at which the parts can be rearranged to provide a different grouping of parts or single/individual parts for further processing. One of the difficulties in an assembly line operation is co-ordinating the movement of the conveyors together with the process of rearranging the parts or the process being performed at the station in an efficient, effective and repeatable way. This is particularly difficult in higher speed assembly processes where the co-ordination has to be done consistently over a very large number of high speed operations.

<CIT> discloses a system for part transfer and transport according to the preamble of claim <NUM>. The document further discloses a method for part transfer and transport comprising:.

In particular, <CIT>, referred to a "Container delivery method, and container delivery device", solves the problem of holding a container such as a syringe in an erected state in the spiral groove of a screw and conveyed. In a container delivery device including a screw in which a spiral groove is formed at an equal pitch and which holds and conveys a syringe in the groove, upper and lower elevating and lowering guides and guiding the side surface of the syringe held in the groove of the screw, a container holding means (robot) holding the syringe and supplying the syringe into the groove of the screw and a following guide guiding the syringe while following and moving the syringe conveyed by the screw, the upper and lower elevating and lowering guides are moved to a retreat position where the syringe is not guided, the syringe held by the container holding means is supplied to the screw and the upper and lower elevating and lowering guides are moved to a position where the syringe is guided while keeping the held state.

As such, there is an on-going need for an improved method and apparatus for part transfer and transport systems in assembly lines.

The disclosure is directed at a method and system for transferring and transporting parts, preferably within an industrial or manufacturing environment. An embodiment of a part transport system of the present disclosure includes a first conveyor system and a second conveyor system. The first conveyor system conveys a grouping of parts, example. parts carried in trays forming a two-dimensional grid, such as a matrix or the like. The second conveyor system conveys a different grouping of parts, i.e. individual parts in a linear arrangement of singulated part spaces. The part transport system further includes a part selection apparatus, i.e. a pick and place apparatus, for transferring a part from the first conveyor system to the second conveyor system. The part transport system provides improved coordination between the first conveyor system, the part selection apparatus, and the second conveyor system relative to the prior art. Further details on embodiments of the part selection apparatus are provided below. In this document, the term "part" is used, however, it will be understood that this may include a finished product, sub-assembly, or the like depending on the application.

Turning to <FIG>, a schematic diagram of an embodiment of a system <NUM> or apparatus for transferring and transporting parts is shown. The part transport system <NUM> includes a first conveyance, or conveyor, system <NUM>, for transporting trays <NUM> of a set of parts to a selection apparatus <NUM> (sometimes referred to as a pick and place apparatus <NUM>). In some embodiments, the trays <NUM> may be delivered to the first conveyor system <NUM> using other or alternate forms of conveyor system, such as an automatic guided vehicle (AGV) <NUM>.

It will be understood that in some embodiments, the trays, seen as full trays 14A, carry a matrix (rows and columns) of the same part, however, different products or parts may also be present within a single tray. In some embodiments, the first conveyor system <NUM> carries or delivers a plurality of trays 14A to the selection apparatus <NUM>. In some embodiments, the trays 14A may be full or may be partially full. The trays contain a two-dimensional grid or matrix of parts.

In some embodiments, the trays <NUM> may be placed on the first conveyor system <NUM> in a stacked manner. In this case, after receiving the stacked trays, the trays 14A may be unstacked at an optional unstacking station 17A. In some embodiments, to monitor part quality, the part transport system <NUM> or the first conveyor system <NUM> may include an optional part testing station 17B configured to performs tests on one or more parts in the tray 14A to determine if the part is suitable for further processing. In some cases, this may be a pass/fail determination. In some cases, if the part is marked as "fail", it will not be transferred to the second conveyor system <NUM>. In other cases, if the part is marked as "fail", once placed on the second conveyor system <NUM> the part will be redirected to a secondary location for remediation, recycling or destruction. It will be understood that the unstacking station 17A and part testing station 17B are not necessarily required in embodiments as claimed.

The part transport system <NUM> or first conveyor system <NUM> may further include an indexing apparatus <NUM> for indexing the trays that are being received in order to track and correlate the parts when they are transferred to the second conveyor system <NUM>, and, ultimately, the final destination. The indexing apparatus may include a barcode scanner (not shown), camera (not shown), near field reader (not shown) or the like that are positioned appropriately in relation to the first conveyor system <NUM> in order to track the parts. For example, in some embodiments, the indexing apparatus <NUM> scans barcodes associated with each of the parts, each of the trays <NUM>, or the like and then stores this barcode and other information into a database <NUM>, other storage medium or the like. The indexing apparatus <NUM> may also receive and provide control signals to the selection apparatus <NUM> and may include a processor for executing computer readable instructions on a computer readable medium for analysing and handling the control signals. The indexing apparatus <NUM> may also receive control signals from the part testing station station 17B with regard to the status of the parts (for example, "pass" or "fail") in the tray <NUM> for use in further processing.

One or more selection apparatuses <NUM> retrieve a group of parts, in this case, a linear array of parts, for example, a row of parts, from a full (or partially full) tray 14A as the tray 14A enters the area of the selection apparatus <NUM>. As noted above, in some cases, the row may not be a complete row and there may be gaps between successive parts. The selection apparatus <NUM> then transfers each of the retrieved parts onto a second conveyor system <NUM>. In some embodiments, the parts may be transferred into a linear arrangement of containers <NUM> that travel along the second conveyor system <NUM>. In this example, the second conveyor system includes two flexible chain conveyors <NUM>. Each flexible chain conveyor <NUM> includes an out path section <NUM> and a return path section <NUM> along which containers <NUM>, either full (18A) or empty (18B), traverse. The containers <NUM> receive parts removed from the trays 14A by the selection apparatus <NUM>. The containers <NUM> then move along the flexible chain conveyor <NUM> along the out path sections <NUM> to be delivered to a predetermined destination where the containers <NUM> can be emptied so the parts can undergo further processing. Empty containers 18B are then transported over the return path sections <NUM> for re-filling by the selection apparatus <NUM>. In some embodiments, the tray and/or part information retrieved when the part is delivered to the selection apparatus <NUM> may be associated with each full container 18A carrying the transferred part in order to track the part through the process. Further details with respect to the selection apparatus <NUM> are provided below. It will be understood that the second conveyor system <NUM> may also be another type of conveyor system and may or may not require the containers to carry the parts. For example, the second conveyor system may be a linear motor conveyor system or the like. Further, the second conveyor system <NUM> is shown with containers arriving and departing on the same side of the first conveyor system <NUM> with a turnaround 20A to reverse the direction but this is not required and the second conveyor <NUM> may be arranged as a flow-through.

The first conveyor system <NUM> further includes a tray return section <NUM> where empty trays 14B or trays containing only "fail" parts, are fed from the selection apparatus <NUM> and may be further transported for refilling. In some cases, the trays 14B may be moved to an empty AGV <NUM>, which then returns the empty trays to a predetermined destination, such as, but not limited to, a part filling station (not shown). In some embodiments, the empty trays may be stacked at the tray return station <NUM> or the like before being returned to the empty AGV <NUM>.

Turning to <FIG>, a schematic top view of another embodiment of a part transfer and transport system <NUM> is shown. It will be understood that this embodiment is intended to further illustrate the concepts herein and elements in this embodiment may be combined, with other embodiments as would be understood by one of skill in the art on reading this document. The part transport system <NUM> includes similar elements as the embodiment of <FIG> and similar numbering will be used accordingly. The part transport system <NUM> includes a first conveyor system <NUM> and a second conveyor system <NUM> as well as one or more part selection apparatuses <NUM> (in this case, three) for transferring parts from the first to second conveyor systems. The transport system <NUM> may also include the indexing apparatus <NUM> and the database <NUM>. Within the second conveyor system <NUM>, the flexible chain conveyors <NUM> may include one or more buffers <NUM> on the out path sections <NUM> and/or the return path sections <NUM>. The buffers <NUM> allow for better control of the movement of the containers/parts along the second conveyor system <NUM> by allowing for storage/delay of movement of selected containers/parts.

Turning to <FIG>, an enlarged schematic view of the selection apparatus <NUM> of <FIG> is shown. <FIG> provides a general indication of where different actions performed by the selection apparatus <NUM> occur. Area A reflects the return path <NUM> where the empty containers 18B are returned for filling by the selection apparatus <NUM>. Area B reflects the out path <NUM> where a full container 18A is transferred from the selection apparatus <NUM> to a predetermined location where the container can be unloaded or emptied. Area C reflects the area where the selection apparatus <NUM> picks up a grouping of parts (e.g. a row) from one of the trays 14A and then transfers this grouping of parts to the second conveyor <NUM>. Area D reflects an area where a feed screw <NUM> (shown in <FIG> and <FIG>) receives incoming empty containers 18B and adjusts the positioning of the empty containers (such as by adjusting the pitch) so that one or more containers 18B are ready for receiving the grouping of parts from the selection apparatus <NUM>. The feed screw <NUM> defines a plurality of singulated part spaces separated by a part pitch along the second conveyor <NUM>. In some cases, the second conveyor <NUM> includes a plurality of containers <NUM> for carrying individual parts and each singulated part space of the feed screw <NUM> is sized to receive one of the containers. In some embodiments, the feed screw <NUM> manipulates the pitch of the empty containers 18B to match the pitch of the parts being held by the grippers so that the parts can be inserted into the empty containers 18B.

In use, the feed screw <NUM>, or timing feed screw, can provide an added benefit to the system as it is able to control and adapt the movement of the empty containers 18B along the return path <NUM> to the requirements of the selection apparatus <NUM>. In other words, the positioning of the empty containers 18B within the second conveyor system <NUM> can be controlled with respect to the selection apparatus <NUM> in order to facilitate the placement of the part within the empty container 18B. The timing feed screw <NUM> may provide a degree of precision and reliability for positioning the empty containers, which can be beneficial in a high-speed manufacturing environment. For example, pitching by the feed screw <NUM> can help to more easily place the parts in containers after the parts have been manipulated by the pick and place apparatus. Along with the positioning, the timing feed screw <NUM> may also assist to control the timing in which the empty containers18B pass by the selection apparatus <NUM>. In some cases, the second conveyor system <NUM> can also provide driving force, drive pressure or the like to the timing feed screw <NUM> to assist in its operation.

<FIG> is an exploded perspective view of an embodiment of the selection apparatus <NUM>, in this case, a pick and place apparatus for transferring the grouping of parts from the tray 14A to the containers 18B. As can be seen, the pick and place apparatus includes a set of grippers <NUM> that grip and hold the grouping of parts (retrieved from the tray 14A). Further details of the transfer of the part <NUM> will be described below.

Turning to <FIG>, a schematic diagram showing additional detail for an embodiment of the second conveyor system <NUM> is shown. In this embodiment, the flexible chain conveyors <NUM> of the second conveyor system <NUM> pass through the selection apparatus <NUM> where an empty container 18B is filled with a part by the selection apparatus <NUM>. In general, the second conveyor system <NUM> transports parts from the selection apparatus to downstream equipment, at a predetermined destination, for processing or emptying of the containers. In some cases, the container may be empty or hold a "fail" part (due to the rejection of a part or the like) when leaving the selection apparatus <NUM>. In this case, the system <NUM> may also include a container separation area <NUM>, a void separation station <NUM>, and/or a container merge section <NUM>. At the container separation area <NUM>, the containers <NUM> may be diverted to a parallel and/or adjacent conveyor in order to introduce gaps between containers and/or to disengage the nesting of containers with each other. In this case, the parallel and/or adjacent conveyor may be operating at a faster speed. At the void separation section or station <NUM>, the apparatus determines if the container leaving the selection apparatus <NUM> is full or empty. If it is full, the container 18A continues along the out path <NUM> towards the predetermined destination. If the container is empty, the empty container 18B can be diverted back to the selection apparatus <NUM> via the return path <NUM> and merge with other empty containers at the merge section <NUM>. There may also be an alternate path for "fail" parts that are being sent for further processing or the like.

<FIG> are views of an embodiment of the selection apparatus <NUM>. <FIG> and <FIG> are right and left side perspective views, <FIG> is a front view, <FIG> is a left side view, <FIG> is a section view along the section line A-A in <FIG>, and <FIG> is a top view. The selection apparatus <NUM> is driven by a drive shaft <NUM>, which rotates a cam assembly <NUM>. The cam assembly <NUM> is used for high-speed, consistently repeatable actions over long periods of time and operations with less chance of wear than servo-based systems. A tray 14A enters the front of the selection apparatus <NUM>, where the grippers <NUM> grip a group of parts <NUM> (a linear array of parts) and rotate the parts <NUM> degrees, where they are transferred to second grippers <NUM>, which then deposit the parts into containers 18B which are brought into alignment with the second grippers <NUM> by the second conveyor system <NUM>. The containers 18B are in a linear arrangement to match with the grippers <NUM>.

The grippers <NUM> and <NUM> may also move up-and-down, and from side-to-side during operation. For example, with reference to <FIG>, the grippers <NUM> and <NUM> may rise during a first phase (identified by numeral <NUM>), rotate inward towards each other during a second phase (identified by numeral <NUM>), and move sideways towards each other during a third phase (identified by numeral <NUM>). Accordingly, with reference to <FIG>, the cam assembly <NUM> may include a vertical motion cam subassembly <NUM> for raising and lowering the grippers <NUM> and <NUM>, a rotational motion cam subassembly <NUM> for rotating the grippers <NUM> and <NUM>, and a horizontal motion cam subassembly <NUM> for moving the first and second set of grippers towards and away from each other. The cam subassemblies <NUM>, <NUM>, <NUM> are configured with cam profiles that synchronize operation of the grippers <NUM> and <NUM> to facilitate transfer of the array of parts from the first conveyor system <NUM> to the second conveyor system <NUM>.

As shown in this embodiment, the cam subassemblies <NUM> and <NUM> may include pairs of cam plates for driving corresponding linkage pairs. As shown, the pairs of cam plates may have different cam profiles based on their corresponding linkage configurations. Even though the cam profiles are different, the pairs of cam plates may cooperate with the linkages to provide mirrored motion, which can help provide operational stability when moving the grippers <NUM> and <NUM>.

In some embodiments, there may be a gripper controller <NUM> (shown schematically) for timing opening and closing of the grippers in synchronization with the cam assembly <NUM>. For example, the gripper controller <NUM> may be a PLC for pneumatically controlling the grippers <NUM> and <NUM>. Accordingly, the gripper controller <NUM> may actuate valves for controlling pneumatic pressure. In other embodiments, the grippers <NUM> and <NUM> may be controlled using other mechanisms, such as servos, cam drivers, and the like.

In some embodiments, motion of the grippers <NUM> and <NUM> may be controlled to have matching movements for the vertical, rotational, and/or horizontal motion phases (identified by numerals <NUM>, <NUM>, and <NUM> in <FIG>).

<FIG> shows a flowchart of an embodiment of a method of part transfer and transport <NUM>. Initially, at least one tray of parts is received. The parts are arranged within the tray, typically in a grid format. In some embodiments, there may be more than one tray and the trays may arrive stacked whereby the trays are then unstacked by the system before the method commences.

The at least one tray travels along a first conveyor system and, optionally, an identification code associated with the single tray or with the parts therein is scanned (<NUM>). The identification code may be scanned while the tray is moving or at a scanning station. The identification code may also include information associated with the parts within the tray such as, but not limited to, production date, part code, part size and the like. The identification code can then be stored in a database <NUM> or on a storage medium for later retrieval by the system (<NUM>).

In some embodiments, the method may optionally include a test performed on the parts to determine if the parts conform to expected characteristics. For example, a test may be performed to confirm that a size of a part does not exceed expected dimensions. If there are non-conforming parts, they can then be removed or may not be picked up by the selection apparatus/pick and place apparatus and left in the tray based on control signals from a processor that is controlling the operation of the system.

In some embodiments, the trays are moved into alignment with the pick and place apparatus by a servo walking beam to place the tray in a proper position for the retrieval of products from the tray.

As the tray is brought into alignment with the pick and place apparatus, empty containers for transporting individual parts are received by the pick and place apparatus via a second conveyor system. Identification information associated with each of the containers, for example, from a barcode, a near field tag (for example, a radio frequency identification (RFID) tag) or the like on the container, may be scanned and then saved within the database (<NUM>). As will be understood, this may be performed in parallel with respect to the scanning of the tray code and the storage of the tray code.

In some embodiments, the feed screw <NUM> is used to align a plurality of containers with the pick and place apparatus such that the pitch of the containers is adjusted to a preferred pitch for receiving the parts (<NUM>). The feed screw <NUM> may be servo controlled, cam driven, a cam drive, and/or may be driven by the second conveyor system.

The pick and place apparatus then retrieves an array, matrix or group of parts from the grid, for example, a row of parts (<NUM>). The row of parts is then manipulated by the pick and place apparatus (<NUM>) as needed to orient the row of parts for placement into the containers. The row of parts is picked from the tray and then rotated <NUM> degrees before being passed to a second pick apparatus which rotates the row of parts a further <NUM> degrees before placing them into the containers.

Once oriented, the parts are inserted into the individual containers in a linear arrangement, and each container is associated with a part (<NUM>) such as by matching, or assigning, the container ID information (from, for example, the RFID tag or the like) with the identification code obtained from the tray. This combined information may then be stored in the database and/or transmitted to another processing unit. The filled containers are then transported on the second conveyor system for delivery to a designation location (<NUM>). The process is then repeated with another row of parts and empty containers until the tray is emptied (<NUM>).

Although the present disclosure has been illustrated and described herein with reference to embodiments and specific examples thereof, it will be readily apparent to those of ordinary skill in the art that other embodiments and examples may perform similar functions and/or achieve like results.

Claim 1:
A system (<NUM>) for part transfer and transport, the system comprising:
a first conveyor system (<NUM>) for transporting a plurality of trays (<NUM>) containing a two-dimensional grid of parts;
a second conveyor system (<NUM>) for transporting the parts to a predetermined destination in a linear arrangement; and
a selection apparatus (<NUM>) for transferring a linear array of parts selected from the grid of the first conveyor system to the linear arrangement of the second conveyor system, the selection apparatus comprising:
a pick and place apparatus (<NUM>) for moving the parts, the pick and place apparatus comprising a
first set of grippers (<NUM>) for picking the linear array of parts from the tray along the first conveyor; and
a feed screw (<NUM>) defining a plurality of singulated part spaces separated by a part pitch along the second conveyor to facilitate insertion of the linear array of parts into the linear arrangement,
characterized in that the pick and place apparatus (<NUM>) further comprises:
a second set of grippers (<NUM>) for receiving the linear array of parts from the first set of grippers, and subsequently placing the linear array of parts into the singulated part spaces along the second conveyor;
wherein the first set of grippers (<NUM>) provides the linear array of parts with a first rotation, and the second set of grippers (<NUM>) provides the linear array of parts with a second rotation to provide a full inversion of the parts.