Anti-Vandalism Protective Attachment Device for a Pay Telephone

This invention relates to anti-vandalism protective devices for pay telephones, amd more particularly to a protective device for the dialing mechanism of a pay telephone.

A main object of the invention is to provide a novel and improved protective device for the dial mechanism of a pay telephone, the device being simple in construction, being easy to install, and having rugged parts which are able to resist heavy impacts and which are arranged to completely shield the fragile dial mechanism of the telephone while allowing it to be operated in a normal manner.

A further object of the invention is to provide an improved anti-vandalism shield assembly for the dial mechanism of a pay telephone which allows the dial mechanism to be operated in a customary fashion, which adequately protects the dial mechanism from impacts imparted to the telephone by angry customers or by vandals, and which does not adversely affect either the operation or the appearance of the telephone.

A still further object of the invention is to provide an improved anti-vandalism shield assembly for the dial mechanism of a pay telephone, the shield assembly being capable of economical manufacture, being capable of being readily installed in the field as a complete unit without requiring special tools, being compact in size, and being attractive in appearance.

A still further object of the invention is to provide an improved pay telephone anti-vandalism shield assembly for protecting the dial mechanism of a pay telephone against damage by vandals, without interfering with its operation, the assembly being devised to protect the telephone dial mechanism from being dislodged or mutilated, to prevent any access to the dial mechanism itself, to prevent the dial assembly from being forced inwardly by heavy impacts whereby to prevent destruction or damage to internal components, and to minimize replacement costs for damage by vandals.

Further objects and advantages of the invention will become apparent from the following description and claims, and from the accompanying drawings wherein:

FIG. 1 is a perspective view of a typical pay telephone provided with an improved anti-vandalism shield device according to the present invention.

FIG. 2 is a perspective view, partly broken away, of the pay telephone of FIG. 1 with the anti-vandalism shield device separated therefrom prior to installation.

FIG. 3 is an enlarged cross-sectional view taken substantially on line 3--3 of FIG. 1, showing one form of the protective shield assembly according to the present invention, with the dial drive element thereof and associated fastening parts disassembled.

FIG. 4 is an enlarged front elevational view of the protective shield assembly of FIG. 1.

FIG. 5 is an exploded perspective view showing the components of another form of protective shield assembly according to the present invention.

FIG. 6 is a cross-sectional view similar to FIG. 3 but showing the assembled protective shield assembly of FIG. 5.

FIG. 7 is a fragmentary vertical cross-sectional view taken substantially on line 7--7 of FIG. 6.

FIG. 8 is a vertical cross-sectional view generally similar to FIGS. 3 and 6, but showing another modification of a pay telephone dial protective shield assembly in accordance with the present invention.

The dialing assemblies of pay telephones have been particularly vulnerable to damage by vandalism, sometimes by angry and frustrated users because of bad service, or by malicious individuals. Angry users or malicious invididuals generally tend to employ the telephone receiver as a hammer or buldgeon and use it to strike the dial assembly, causing serious damage thereto and often driving the dial assembly inwardly, creating serious damage to or destruction of the delicate and expensive internal components of the telephone installation.

A prime purpose of the present invention is to provide an effective guard shield assembly which will protect the dial mechanism and shield it and the internal parts adjacent thereto from damage or destruction by such hammer blows, as well as to prevent any access to the dial mechanism by prying implements such as knife blades, screwdrivers, the receiver hang-up lug, or the like, without interferring with normal usage of the dial mechanism.

Referring to the drawings, and more particularly to FIGS. 1 through 4, a conventional pay telephone is illustrated generally at 9, the telephone being provided with a hook-supported hand set or receiver 10. FIG. 1 shows a protective shield assembly 11 according to the present invention installed over the circular dial aperture 12 in the front wall 13 (see FIG. 2) to which the rotary dial member 14 is normally exposed. Dial member 14 has the circularly arranged finger holes 15 through which the dial numbers are normally visible. The dial assembly also includes an inwardly extending finger stop lug 16 for stopping clockwise rotation of member 14 when rotated by a finger in one of the holes 15. The shield assembly 11 shown in FIGS. 1 through 4 comprises a generally annular cover member, or main support member, 17 which is secured concentrically around aperture 12 by a plurality of fastening screws 18, engaged from the inside of the telephone housing 19 through apertures 20 in the front walls 13 of the housing, spaced around dial aperture 12, as shown in FIG. 2, and engaged in tapped holes 60 in member 17. The outer surface of cover or support member 17 is smoothly contoured with no projections or protuberances. The member 17 is formed with a front flange 21 to define a generally circular front opening 22 and is recessed inwardly therefrom to define a frusto-conical annular bearing surface 22. Member 17 is annularly recessed at 23 to receive an annular raceway member 24 having a reduced generally annular inner end portion 25 which is receivable in the dial aperture 12 around member 14. The end portion 25 is suitably notched to receive finger lug 16.

Raceway member 24 is formed opposite bearing surface 22 with a cooperating frusto-conical bearing surface 26, forming a V-shaped annular outer groove for bearing balls 27. A disc-like substitute dial member 28 is rotatably received in the center plane of said V-shaped groove and has a corresponding outwardly facing peripheral V-shaped groove 29 forming the inner raceway seat for the balls 27. Member 28 is retained between flange 21 and the shouldered portion 61 of member 24 adjacent bearing surface 26, as shown in FIG. 3.

Member 28 is formed with circularly arranged forwardly facing finger-engagable recesses 30 located to register with the dial holes 15 of member 14.

A rearwardly directed drive sleeve member 31 is secured by a bolt 32 and nut 33 to the rear surface of member 28 in axial alignment with the zero recess 72. As shown in FIG. 3, the inner end wall of this zero recess 72 is formed with a central hole 34 to receive the bolt 32, and the drive sleeve 31 is engaged on bolt 32, being clamped thereto by nut 33. Sleeve 31 projcts rearwardly sufficiently to engage in the zero hole 74 of dial member 14. Thus, sleeve 31 provides a driving connection between substitute dial 28 and original dial member 14 when the device 11 is secured on the telephone 9 in the manner shown in FIG. 1. A coil spring 35 surrounds sleeve 31 and bears between member 14 and member 28.

Support member 17 is formed with an inwardly extending finger stop plug 36 (see FIG. 4), which is in registry with lug 16 when device 11 is intalled on the telephone 9. Stop lug 36 acts in the same manner as lug 16 to limit rotation of said substitute dial 28.

The recesses 30 are provided with number-bearing indicia discs 37 suitably secured in the recesses to numerically identify the number recesses 30.

With the device 11 secured on the front wall of the telephone housing 19 in the manner shown in FIG. 1, the substitute dial 28 is employed in the same manner as original dial element 14, using the recesses 30 for finger engagement. The return spring means of the telephone dial mechanism returns the substitute dial to starting position when the recesses 30 are released.

FIGS. 5, 6 and 7 shows another form of the present invention, wherein the protective shield device is designated generally at 11'. The shield device 11' comprises a generally annular cover member, or main support member, 17', similar to the previously-described member 17, which is secured concentrically around the dial aperture 12 by a plurality of fastening screws 18, as in the previously-described form of the invention. Member 17' has the front flange 38 formed with the inwardly projecting finger stop lug 36. Received in the member 17' is an annular raceway assembly comprising an annular inner member 39, a main ring-like body 42 and a flat inwardly projecting retention ring 43 which are rigidly secured together in any suitable manner. The reduced inner end portion 40 of the ring 39 is engagable in the dial aperture 12 around dial member 14, and has a notch 41 to receive the finger stop lug 16. The raceway assembly has an inwardly facing channel 70, in the opposite corners of which are received respective sets of circularly arranged bearing balls 44 and 45 disposed on opposite sides of a peripheral divider rib 46 on the substitute dial member, shown at 28', which is thus rotatably and coaxially mounted in the main support member 17', being retained therein at its front side by flange 38 and at its rear side by the member 39.

Substitute dial 28' has the circularly arranged number recesses 30', registrable with the number holes of dial member 14 when device 11' is installed on the telephone housing 19, the stop lugs 36 being then in registration with the normal finger stop lug 16. A drive assembly is secured to the rear surface of substitute dial 28' in axial alignment with the zero number recess 72' and is drivingly engagable with the zero hole 74 of the dial member 14 of the original dial assembly. The drive assembly comprises a flanged sleeve 49 mounted on a connecting bolt 47 extending through a counterbored axial hole 48 in the end wall of said zero recess 72', and clampingly held by a nut 50 threaded on the rear end of the bolt. An annular cap member 51 is loosely mounted on sleeve 49, facing the flange 52 of the sleeve. A coiled spring 53 surrounds sleeve 49, bearing between flange 52 and cap member 51 and is received in said cap member, as shown in FIG. 6. Nut member 50 retains cap member 51 on sleeve 49. However, the loose fit of cap member 51 on the sleeve allows sufficient movement to facilitate the engagement of cap member 51 in the zero hole 74 of dial member 14 in installing the device, and to enable the cap member 51 to be automatically adjusted to properly fit the zero hole 74, if there is any mis-alignment between the substitute dial 28' and the dial member 14.

The assembly of the parts shown in FIGS. 5, 6 and 7 is held together as a unit by headed retention screws 65,65 (FIG. 5) engaged in diametrically opposed tapped countersunk holes 66, 66 provided in the rim of member 17', with the heads of the screws retentively overlying the member 39.

The device 11' is preassembled at the factory as a complete unit which can be easily handled in the field and which can be quickly and easily installed on existing public pay telephones, merely requiring the drilling of holes 20 in the front wall 13 of the telephone housing 19 for receiving the fastening screws 18.

FIG. 8 illustrates another embodiment of the invention, wherein the reduced inner end member 40' of the raceway assembly is extended and externally threaded to receive a clamping ring 54 which is threadedly engaged thereon. Ring 54 exerts clamping pressure on a washer 55 interposed between the ring and the adjacent front wall 13 of housing 19, and thereby clamps the raceway in the dial aperture 12.

While certain specific embodiments of protective anti-vandalism shield devices for the rotary dial assemblies of pay telephones have been disclosed in the foregoing description, it will be understood that various modifications within the spirit of the invention may occur to those skilled in the art. Therefore, it is intended that no limitations be placed on the invention except as defined by the scope of the appended claims.