Patent Grant
8408080
The present invention relates to inspection machines for small precision parts, and more particularly, to an optical and mechanical inspection station capable of high speed sorting and high-tolerance checking down to 0.0001″ (controlling thickness to very tight tolerances), and coining to perfect deformed, bent or oversize parts.
The present invention is an automated system comprising an adaptable combination of optical inspection stations and precision mechanical gauge stations for high-speed small-tolerance inspection, and a coining station to repair bent, deformed or oversize (excessively thick) parts. An additional mechanical gauge station verifies that the parts were repaired according to the specified tolerances. The system architecture is adaptable to inspecting and repairing any precision metal parts with small or polished surface features, and is particularly well-suited for inspecting and repairing the locking bar and rack of a rekeyable lock cylinder, and for inspecting and sorting the welded pins therein. The present inspection stations allow parts tolerance verification of these extremely small parts in a cycle time between 0.7 to 2.3 seconds, which can potentially raise production with higher yields from 110M parts/year (by 100% manual inspection) to 275M parts/year by automated inspection and part “coining” (repairing).
Coining is a known method of precision stamping in which a workpiece is subjected to a sufficiently high stress to induce plastic flow on the surface of the material. Coining is used to manufacture parts for all industries, and when referred to herein connotes reforming existing parts with high relief or very fine features to correct imperfections. Thus, the present system is a high-volume inspection system for small precision parts capable of both detecting and correcting imperfections.
The present system may incorporating various combinations of visual inspection station(s), mechanical inspection station(s), and a coining station, as appropriate for the production parts. The stations are modular, and there may be different production scenarios for each of the racks, pins and locking bars, depending on demand. The speed of the system is achieved by a novel ultra-high-speed pneumatic sorting/positioning matrix that reorients the components into the various camera-inspection and mechanical-gauge-inspection stations for combined gauge and visual tolerance checking.
By way of background
To rekey the lock cylinder 10, a valid key is inserted into the keyway 52 and is rotated approximately 90 degrees counterclockwise or clockwise from the home position. A learning tool or other pointed device is inserted into the rekeying tool opening 54 and is pushed against the carrier 90 to move the carrier 90 parallel to the longitudinal axis of the lock cylinder 10 into a learn mode. The valid key is removed and a second valid key is inserted and rotated clockwise or counterclockwise. The carrier 90 is biased toward the plug assembly 14 face by the return spring 98, causing the racks 92 to re-engage the pins 113. The racks 92 each include a frontal pin-engaging surface having a plurality of gear teeth configured to engage the annular gear teeth of the pins 113, a semi-circular recess at the bottom, and a backside surface with a plurality of anti-pick grooves and a pair of locking bar-engaging grooves. The plurality of spring-loaded pins 113 are generally cylindrical with annular gear teeth and a central longitudinal bore for receiving biasing springs 115. The spring-loaded locking bar 94 is configured to fit into a recess in the carrier 90 and also includes triangular edges configured to fit into grooves.
The racks 92, pins 113 and locking bar 94, are small extreme precision parts that must be manufactured to very tight tolerances. In a production environment this necessarily entails a thorough 100% inspection and, where necessary, coining for compliance before use in the field. It should be apparent from
What is needed is an automated or semi-automated inspection process that can raise production and quality levels drastically, via a system with automated optical and mechanical inspection stations using a configuration that is adaptable to inspecting the locking bar, the rack, and the pin, and for automated coining (resizing) and sorting of bent or oversize racks and locking bars that exceed drawing specifications to meet tight tolerances.
It is also desirable that the inspection system be modular. A thorough inspection involves a combination of visual inspections and mechanical gauge inspections, optionally followed by coining of components that failed an inspection. The racks 92, pins 113 and locking bar 94 differ, and production requirements may vary. It follows that the particular combination and sequence of inspections and coining may vary. Consequently, for each component part there may be several suitable system configurations available to satisfy the various inspection and/or coining needs.
The present system accomplishes the foregoing for the components of rekeyable lock cylinders including racks, pins and locking bars, as well as any other small high-precision parts that must be manufactured to very tight tolerances. The system is modular and easily reconfigurable to accommodate possible variations in system configuration and operation. Despite the desired number or sequence of inspections, it remains necessary to sort, convey and orient the components through and into each of the plurality of inspection/coining stations. This high-speed sorting, conveying and orientation is herein achieved with an ultra-high-speed pneumatic sorting/positioning matrix that reorients the components into the various camera inspection and gauge stations for combined gauge and visual tolerance checking. Defects are identified by a combination of visual and machine-gauge inspection, and the components are sorted into three bins: 1) rejects; 2) good parts; 3) parts for coining. The sorters orient and feed the components to a dispenser that dispenses the sorted components single file from a queue.
Rather than merely sorting components for coining, the system can also be configured with an integral coining station for resizing the parts, followed by a mechanical thickness gauge for checking the coining result. The automated optical and mechanical gauge inspection station(s), component sorters and component dispensers, and coining station are adaptable to the various machine configurations shown above for each of the locking bar, rack, and pin components, and will herein be described in the context of a Locking Bar System Configuration including a visual inspection station and mechanical gauge for thickness and straightness sorting of the locking bar in the X-Direction, a component sorter for 90° part rotation, and then another visual inspection station and mechanical gauge for thickness and straightness sorting in the Y-Direction.
For each component part there may be several suitable system configurations available to satisfy the various inspection and/or coining needs. For example, the following configurations of the present system are suitable for the various components as follows:
1. Rack System Configurations (3 Examples)
In each of the foregoing system configurations it is possible to electronically enable or disable all or some of the stations. For example, for the Locking Bar System Configuration (a), it is possible to turn OFF the visual inspection station and leave ON the Mechanical Gauge, or vice versa.
The system as a whole is capable of tolerance-checking down to 0.00011811″, with a repeatability of 0.00005906.
Other objects, features, and advantages of the present invention will become more apparent from the following detailed description of the preferred embodiments and certain modifications thereof when taken together with the accompanying drawings in which:
The present invention is an automated optical and mechanical inspection, sorting and coining system capable of high speed sorting and small-tolerance checking down to 0.0001″, plus coining and re-inspection to straighten bent or oversized parts. The optical/mechanical inspection and coining system employs an adaptable multi-station architecture suitable for both optical and mechanical inspection, as well as coining and re-inspection, specifically adapted for each of the locking bar, rack, and pin of a rekeyable lock cylinder, and other small parts. Rekeyable lock cylinder components are shown, for example, in U.S. Pat. No. 6,862,909 to Armstrong et al. and
The present system includes a configurable series of optical and mechanical inspection stations, plus sorting and coining stations, that allow parts tolerance verification of extremely small parts in an average cycle time of 1.5 seconds (2.3 seconds (max)), and is capable of tolerance-checking down to 0.00011811″, with a repeatability of 0.00005906″.
The system cycle time is variable from 0.7 to 2.3 seconds subject to the number of sorting stations needed for optical inspection, mechanical gauging and coining, and desired component yields.
The vibrating feeder bowl 10 accepts bulk components onto a vibrating bowl which aligns them against a circular sidewall. The components line-up against the sidewall where they are fed in a continuous stream onto the inline single-file feed vibratory conveyor 20 (arranged as a linear track). The vibrating feeder bowl 10 is continuous motion with adjustable vibration frequency and feed rate. A variety of vibratory feeders are commercially available and will serve as the vibrating feeder bowl 10 so long as it is capable of sorting, orienting and feeding the locking bars (or others parts) single-file to the conveyor 20.
The components are transported by the vibratory feed conveyor 20 in a single file and continuous stream. The feed conveyor 20 may be any suitable small parts conveyor although in the presently preferred embodiment is a vibratory conveyor (linear track). The vibration frequencies and hence the feed rates of both the vibrating feeder bowl 10 and vibratory conveyor 20 are adjusted by individual linear amplifiers (shown and described below with regard to
The sorting assembly 40 includes an ultra-high-speed pneumatic sorting/positioning matrix 60 that singulates, transfers and reorients the components through the various camera-inspection and mechanical-gauge-inspection stations for combined gauge and visual tolerance checking. The embodiment of
More specifically, each locking bar is singulated and gated into the sorting/positioning matrix 60 of sorting assembly 40 from the single-file conveyor 20. The locking bar is then pneumatically transferred through three inspection stations, beginning with a length measurement station 62, then to a first visual inspection station 65 beneath camera 30 for optical inspection, and then to a mechanical gauge station 61 for thickness and straightness sorting. The length measurement station 62 comprises any suitable high-precision length measurement sensor, a linear measurement interferometer being preferred. Optical camera imaging is provided by mast-mounted overhead optical inspection cameras 30 in communication with a remote display such as a laptop computer 90. The camera 30 images the locking bar along an X plane for visual tolerance checking relative to a gradient scale displayed on computer 90. The sorting/positioning matrix 60 then ushers the components through a pre-calibrated mechanical gauge station 61 comprising a digital-output micrometer adjusting a fixed-dimension pass-through gate (described below). The locking bar passes through this first mechanical gauge station 61 for thickness and straightness sorting along an X plane. Locking bars that pass the combined visual and machine-gauge inspections are sorted by a collection station 50 into a good parts bin 52.
Defects identified during the combined visual and machine-gauge inspections are fed to a coining station 80 and then to a supplemental mechanical gauge station 63 for automated coining (remanufacture) and re-inspection of the coined parts. If the coined locking bars now pass the supplemental machine-gauge inspection, they are likewise sorted by collection station 50 into the good parts bin 52.
Second-time defects are sorted by collection station 50 left or right, mechanical gauge rejected parts into bin 51, and optical inspection rejected parts into bin 53.
A programmable controller with a touch screen display 70 synchronizes the entire operation, which, even if coining is required, lasts no more than 2.3 seconds. The operator simply empties mechanical gauge rejected parts from bin 51, good parts (including failed-coined- and now-good parts) from bin 52, and optical inspection-rejected parts from bin 53. The system as a whole is capable of tolerance-checking down to 0.00011811″, with a repeatability of 0.00005906. The automated inspection, sorting and coining system is adaptable with minimal modification for each of the locking bar, rack, and pin components, although the embodiment illustrated and described herein is adapted for inspection of locking bars. The system is highly configurable depending on production needs, owing largely to the flexibility of the sorting/positioning matrix 60. Both number and sequence of inspections may be changed. For example, a second visual inspection may be needed in a Y-plane, and for this purpose a second visual inspection station may be added for tolerance inspection in a Y plane, and a second mast-mounted overhead optical inspection camera 30 also included. In this case the sorting/positioning matrix 60 rotates each locking bar onto its side at a 90° part rotator, and moves it to the second visual inspection station (under a second camera 30) for visual tolerance checking along the Y plane, again relative to a gradient scale displayed on computer 90.
Initially the locking bars enter the fixed-position gate 63 with a defined channel to singulate the parts. A pneumatic slide 82A actuated by opposing pneumatic cylinders 101, 104 then gates the individual parts into the matrix 60 under the control of a programmable controller as monitored on the controller's touch screen display 70. The slide 82A slides back and forth pneumatically under control of opposing pneumatic cylinders 101, 104, and parts are gated into slide 82A when it is in the rightmost position (in this position parts shift from the channel in gate 63 into a corresponding channel in the pneumatic slide 82A). The slide 82A itself comprises a length measurement station 62. Presently, length measurement station 62 allows measurement of the length of the locking bars to nanometer accuracy by interferometric optical fibers embedded in the slide 82A channels, thereby providing a nanometer-accuracy linear measurement of each locking bar.
Next, the pneumatic slide 82A moves left to transport the locking bar into a camera optical inspection stations 65. Again, when the pneumatic slide 82A moves left the locking bar is pneumatically blown from the channel in slide 82A into a corresponding channel in optical inspection stations 65, where the component is effectively held stationary within exceedingly close confines for optical inspection using the overhead mast-mounted camera 30 of
After optical inspection, a second slide 82B shifts left pneumatically under control of opposing pneumatic cylinders 102, 105, and parts are gated into a first mechanical gauge station 61 for mechanical inspection along an X-plane (in this position parts are blown from the channel in optical inspection station 65 into a corresponding channel in the mechanical gauge station 61). Again, the slide 82B moves back to the right to serve as a closed gate. The mechanical gauge station 61 comprises a digital-output micrometer adjusting a fixed-dimension pass-through gate which confirms the thickness of the locking bar.
It should now be apparent that several such slides 82A-C are provided to facilitate movement and gating of the component parts through the various stations, and each is actuated by a pair of opposing pneumatic cylinders 101/104, 102/105 and 103/106 all controlled by the programmable controller 70. The slide positions (left or right) are reported to the programmable controller 70 via sensors mounted on the pneumatic cylinders 101-106.
Depending on the results of the combined inspections, the component is shifted either right or left by pneumatic slide 82C through a singulation station 68 which isolates the component. If it is determined by inspection that the component requires coining, it is transferred left to a coining station 80 which re-manufactures (coins) the parts in real time to resize them. The parts are coined and then sent through a supplemental mechanical gauge 63 to quality-check the coining operation. Coined components that pass the mechanical gauge 63 are gated one-by-one single file through an exit gate 71 at the bottom of the figure, this gating occurring under control of the programmable controller 70. The parts are gated into collection station 50 via a moving shuttle 55 which sorts the parts into good parts bin 52. Coined components that fail the mechanical gauge 63 are shuttled by moving shuttle 55 into mechanical gauge reject bin 51.
Components that do not require coining are gated one-by-one single file through an exit gate 69 at the bottom of the figure, this gating also occurring under control of the programmable controller 70. These components are likewise gated into collection station 50 via a moving shuttle 55 which sorts the parts into the good parts bin 52 or optical inspection rejects bin 53, as appropriate. The programmable controller 70 maintains a synchronous operation by controlling all gating and pneumatics. The inspection performed at each station result in a simple go/nogo determination, the end result of which may be earmarking of parts as good, defective or suitable for coining (remanufacturing).
Referring back to
All pneumatic lines are controlled by corresponding digital on/off solenoid valves connected to the controller. In the illustrated embodiment there are six pneumatic cylinders 101-106 and three corresponding slide inlays 82A-C, and hence there are twelve solenoid valves and pneumatic lines for moving the three slides 82A-C left and right on each side, in addition to the three pneumatic lines and solenoid valves coupled to manifold 90. Fiber optic sensors are used to detect the part entering and exiting slide inlays 82A-C. This information is communicated to the PLC controller 70 for synchronizing the movements of slide inlays 82A-C. This way, part jams can be detected by the PLC 70 via the fiber optic sensors. The PLC 70 will stop the slide inlay 82A-C movements and the jam will be reported by an error message. The six pneumatic cylinders require twelve air lines (each cylinder takes both input and exhaust air lines). This configuration allows centralized automatic high speed synchronous on/off operation, and pressure control, by the programmable controller 70. The pneumatic cylinders, solenoid valves and pneumatic lines are commercially-available for example from SMC Inc.
As the locking bars travel through the matrix 60 and the system as a whole the individual components positions are tracked by fiber optics. Specifically,
Referring collectively to
After leaving the sorting/positioning matric 60 the locking bars are coined at coining station 80, transported to supplemental mechanical gauge station 63 for follow-up mechanical inspection, and sorted by shuttle 55 into one of three bins: 1) Mechanical Gauge rejected parts into bin 51; 2) coined and now-good parts into bin 52; and 3) Optical Inspection rejected parts into bin 53.
If a second (optional) optical inspection along a Y-plane is desired, after step 5 the locking bar may be rotated 90°, transported to a Camera 2 Station for a Y-plane optical inspection, and then transported to mechanical gauge station 61 for mechanical inspection. This entails the addition of a fourth slide, two additional pneumatic cylinders, four solenoids, and a second overhead camera 30, all of which is readily possible given the reconfigurable nature of the system.
At step 1, with reference to
At step 2, the locking bar is singulated within gate 63 (e.g., isolated as a discrete component).
At step 3, slide inlay 82A is displaced right (as shown) and the locking bar enters slide inlay 82A which serves as length measurement station 62. Here it stops for length measurement by a high-precision interferometric length measurement sensor with fiber-optic probe tips embedded in the walls of slide inlay 82A. One skilled in the art should understand that other types of length measurement sensors may suffice for this operation.
At step 4 with reference to
As seen in
At step 6, if the locking bar fails any optical or mechanical inspection, the next slide inlay 82C is displaced left and the locking bar is shifted left into a reject track where it is transferred to reject bin 51 (or optionally coining bin 53). As described above with reference to
All the inspected and optionally coined components accumulate at collection station 50 in the three bins: 1) rejects in bin 51; 2) good parts in bin 52; and 3) optical inspection rejects into bin 53. The parts are gated out of the sorting matric 60 or supplemental mechanical inspection station 63 into collection station 50 via a moving shuttle 55 which collects the parts and moves them into the appropriate bin. Good parts are shuttled to bin 52, parts that fail optical inspection and are not coined are rejected into bin 53, and coined components that fail the mechanical gauge 63 are shuttled by moving shuttle 55 into mechanical gauge reject bin 51. The entire process is controlled by the programmable controller in accordance with the user-settings entered by menus appearing on the touch screen display 70 (
It should now be apparent that the above-described visual inspection station(s), mechanical inspection station(s), coining station(s), and component sorters and component dispensers provide ultra-high-speed pneumatic sorting and reorientation of the components into the various camera inspection and gauge stations for combined gauge and visual tolerance checking. Although the Locking Bar System Configuration described above includes a visual inspection station and mechanical gauge for thickness and straightness sorting in the X plane, one skilled in the art should readily understand that various related configurations are possible depending on the particular component part to be inspected and the inspection goals of the operator. Specifically, it is envisioned that the following combinations will serve the corresponding component parts:
1. Rack-Testing Configurations
In all the foregoing exemplary configurations it is possible to electronically enable or disable all or some of the stations. For example, for the Locking Bar System, Configuration (a), it is possible to turn OFF the visual inspection station and leave ON the Mechanical Gauge, or vice versa.
Having now fully set forth the preferred embodiment and certain modifications of the concept underlying the present invention, various other embodiments as well as certain variations and modifications of the embodiments herein shown and described will obviously occur to those skilled in the art upon becoming familiar with said underlying concept. It is to be understood, therefore, that the invention may be practiced otherwise than as specifically set forth in the appended claims.
The present application derives priority from U.S. provisional application Ser. No. 61/214,711 filed 27 Apr. 2009.
| Number | Name | Date | Kind |
|---|---|---|---|
| 7658291 | Valerio | Feb 2010 | B2 |
| Number | Date | Country | |
|---|---|---|---|
| 20100269602 A1 | Oct 2010 | US |
| Number | Date | Country | |
|---|---|---|---|
| 61214711 | Apr 2009 | US |
