Field of the Invention
This invention relates generally to electronic article surveillance (EAS) systems and pertains more particularly to EAS pedestals and methods for making EAS pedestals.
Background of the Invention
EAS pedestals are commonly found at exits of facilities, such as libraries, department stores and the like, and include, within front and rear covers, antennas (coils) transmitting and receiving radiant energy into and from a surveillance zone adjacent the pedestal to detect active, i.e., non-deactivated, EAS markers (tags). Typically, the markers are deactivated at a checkout counter. Where a party seeks to remove a tagged article from the facility fraudulently, the marker is in an activated state and, when the article enters the surveillance zone, an alarm condition is generated by the EAS system.
EAS pedestals presently known are quite labor-intensive in manufacturing assembly and repair. Common construction for pedestals is either a routed center section that contains the coils and is covered with a thermoformed skin or formica, or a molded center section using a process suitable for producing large housings. Bumpers are used to secure the covers to a main chassis, which complicates initial factory assembly and requires almost a complete disassembly of the pedestal to access the coils and printed circuit boards when field service repair is necessary following pedestal installation at a facility.
Summary of the Invention
A primary object of the subject invention is to provide simplification in EAS pedestal structure and assembly from that heretofore known.
A more particular object of the invention is to simplify both initial factory assembly of pedestals and subsequent access to the pedestal interior as needed in field service.
In the attainment of these and other objects, the invention provides a pedestal assembly for an EAS system, comprising an antenna, an electronic assembly, a support member having at least first and second recesses, the antenna being seated in the first recess and the electronic assembly being seated in the second recess, first and second covers secured to the support member and a top cap member circumscribes upper ends of the first and second covers.
Preferably, the pedestal assembly includes bumpers (sidewalls) mounted on sides of the support member and the bumpers bear lengthwise upon the covers and apply force transversely on the covers.
The electronic assembly may be in the form of a printed circuit board (PCB) arrangement and may include a fan having an exhaust port issuing onto the PCB arrangement and the support member will then be configured with air ducts therein for both communicating ambient exterior air to the intake port of the fan and for exhausting air heated by the PCB arrangement through the top cap member.
The support member may also define channelling for electrical wiring powering the pedestal assembly.
The top cap member is preferably in the form of an alarm lens structure for providing visual indication atop the pedestal assembly of system detection of activated markers.
The support member comprises a two-layer plastic body, one layer of which defines the first and second recesses and the other layer reinforcing the first layer. The two-layer plastic body is preferably a thermoformed molded body or a cold formed bonded assembly.
The invention will be further understood from consideration of the following description of preferred embodiments and methods thereof and from the drawings where like reference numerals identify like parts throughout.
Description of the Drawings
FIG. 1 is a front elevation of a pedestal assembly in accordance with the invention.
FIG. 2 is a top plan elevation of the FIG. 1 pedestal.
FIG. 3 is an exploded perspective view of certain components of the FIG. 1 pedestal.
FIG. 4 is a cross-sectional view as would be seen from plane IV--IV of FIG. 3, with various parts omitted in the interests of clarity.
Detailed Description of Preferred Embodiment and Practices
Referring to FIGS. 1 and 2, upstanding EAS pedestal assembly 10 includes front arcuate cover 12, a rear arcuate cover 14 (FIG. 4) and a top cap member 16 which includes lens 16a and circumscribes the upper ends of the covers. Bumpers (sidewalls) 62a and 62b bear upon covers 12 and 14 as is discussed more fully hereinafter. The pedestal covers include support legs, one being shown at 18 in FIG. 1.
Pedestal assembly interior structure is seen in FIG. 3 to include support member 20, printed circuit board (PCB) assembly 22 having printed circuit boards 22a and 22b, coils 23 and 24 forming loops of a Figure-8 antenna and template 42. A recess 28 is formed generally centrally of support member 20 of configuration complemental to that of PCB assembly 22, so as to receive the same.
Grooves 29 and 30 are formed also in support member 20 of configuration complemental to that of coils 23 and 24, so as to receive and retain the coils with support member 20.
PCB assembly 22 includes a fan 32 which has an exhaust port 32a issuing air onto the circuit boards 22a and 22b for conducting heat away from the circuit boards. Support member 20 defines an air exhaust channel with exhaust port 34 and an intake channel with an exhaust port 36, which is adjacent to the intake port (not shown) of fan 32. Covers 12 and 14 include exhaust vents, that of cover 12 being shown at 12a in FIG. 1. Exhaust air impinging on the undersurface of top cap member 16 is deflected downwardly to issue outwardly of pedestal assembly 10 through the cover vents.
Also defined in support member 20 are electrical wiring channels which have openings 38 and 40 to permit electrical wiring to enter and exit the pedestal. Template 42 is securable to the generally inverted T-shaped lower portion 44 of support member 20 and has a central aperture 42a and external apertures therein for passage of electrical wiring (not shown) into pedestal assembly 10.
A securement member is indicated at 46 in FIG. 3 and a securement recess is indicated at 48 in support member 20. In accordance with particularly preferred practice per the invention, member 46 is a mechanical quick release fastener and recess 48 is formed to accept and retain fastener 46. Referring to FIG. 1, fasteners 50 and 52, also mechanical quick release fasteners, secure the pedestal assembly cover 12 to support member 20, extending through apertures in lower portion of the cover and seating in sockets formed in portions 20a and 20b of the support member. Rear cover 14 is likewise secured to the support member by like structure at the rear of the assembly. Covers 12 and 14 are also secured to support member 20 under top cap member 16, as discussed hereinafter.
Referring to FIG. 4, support member 20 is constituted as a two-layer member, having mutually secured layers 54 and 56. Further, support member 20 has a hollow section for improved strength and has various projections or bosses on its surfaces, one being indicated at 67 in FIG. 3. Recess 28 is formed in layer 56 and the surface bounding recess 28 is desirable formed with undulations 56a which define air ducts below PCB assembly 22 to assist in providing temperature control therefor by conducting forced air from fan 34 therethrough.
Layers 54 and 56 define jointly define projections 58 and 60 lengthwise of support member 20, the projections being configured to retentively seat in channels extending lengthwise through bumpers 62a and 62b. As is seen at the right side of FIG. 4, projection 60 is seated in channel 64 of bumper 62b. Additionally, bumpers 62 and a plurality of bosses (48) formed on layers 54 and 56 are effective so as to compress covers 12 and 14 which increases the vertical strength of pedestal assembly 10.
In reaching the pedestal assembly of the invention, PCB assembly 22 is seated in recess 28 and a plurality of fasteners 46 are passed through PCB assembly mounting apertures 66 into support member 20 sockets 48. Coils 23 and 24 are seated in grooves 29 and 30 and electrical wiring is introduced through secured template 42 through support member 20 channels and connected to PCB assembly 22, inclusive of its fan 32. Coils 23 and 24, jointly forming a single antenna which is time-shared for transmitting and receiving, are energized by transmitter and receiver circuitry of PCB assembly 22.
The assembly bumpers 62a and 62b are applied to the projections 58 and 60 of support member 20. Top cap member 16 is now secured in sockets 20c and 20d of support member 20. Upper ends of covers 12 and 14 are now inserted slidingly into the interior of top cap member 16 and the cover lower ends are now secured to support member 20.
In field service, a technician can readily remove the covers by unsecuring their lower ends from the support member and downwardly sliding covers 12 and 14 from top cap member 16. The PCB assembly is thus immediately accessible, as are the coils.
The support member comprises, as noted, a two-layer plastic body, either layer of which defines a singular or plurality of features above discussed. In preferred practice per the invention, the support member is a thermoformed molded body, but the invention is not limited to this process.
In its method aspect, the invention will be seen to involve the steps of preforming a support member with recesses of configuration to receive an electronic assembly for an EAS pedestal and an antenna, inserting the electronic assembly and antenna into the recesses and securing the same and connecting electrical wiring thereto, applying bumpers to sides of the support member and securing a top cap member to the support member and to provide a preassembly. First and second covers are formed with an arcuate configuration to jointly enclose front and rear sides of the preassembly. Upper ends of the covers are slidably inserted interiorly of the top cap member. Lower ends of the covers are secured to the support member in facing relation to the front and rear sides of the preassembly, completing the assembly.
In the preferred practice, the support member is further formed with sideward projections and the bumpers are formed with channels for receiving the projections. The bumpers are applied to receive the projections and marginal portions of the first and second covers are placed in abutment with the bumpers and the support member so as to provide interference between the components and to compress the covers transversely to increase vertical strength. The top cap member is a preferably formed so as to provide a channel for retentively circumscribing upper ends of the covers and upper ends of the bumpers intervening the covers.
Various changes to the particularly depicted embodiment and described practices of the invention may be introduced without departing from the scope of the invention. Accordingly, it is to be appreciated that the particularly disclosed embodiments and practices are intended in an illustrative, and not in a limiting, sense. The true spirit and scope of the invention is set forth in the ensuing claims.