US 3379932 A
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April 23, 1968 w. 5. LEGGE 3,37
FOOT GROUNDING DEVICE Filed July 8. 1966 W ,2 ll
7 INVENTOR ATTORNEY United States Patent 3,379,932 FOOT GROUNDING DEVICE Walter G. Legge, Brooklyn, N.Y. (101 Park Ave, New York, N.Y. 10017) Filed July 8, 1966, Ser. No. 563,730 1 Claim. (Cl. 317-2) ABSTRACT OF THE DISCLOSURE This invention relates to a conductive foot covering, and more particularly to a conductive rubber footwear designed to be worn over a shoe as a component of a body grounding device.
The invention has for an object to provide a novel conductive foot covering adapted to be worn over the shoe and capable of establishing a grounded connection between the body of the wearer and a grounded floor or surface to the end that the risk of explosion as a result of static spark from the wearer may be reduced to a minimum.
Devices of this general type are subject by their nature to be worn in atmospheres which contain gases and vapors which have a deteriorating effect on its components and in particular, on those which are provided to maintain them in position on the wearers person. It is common to employ elasticized foot bands, for example, on those designed to be worn on the shoe. These bands deteriorate quickly in such atmospheres. It is desirable therefore to use bands made of a material resistant to gases and acids and fashion the band so that the device still may be worn selectively over shoes and boots of different shapes and sizes. To this end the conductor foot covering made according to the present invention is provided with a band made to pass over the top of the shoe and which is fabricated of a plastic material or other gas resistant material. Due to the fact that the band is non-elastic, it is composed of two parts each connected to one end of the carbonized rubber conductor which is in conductive contact with the floor when worn on the foot with the free ends thereof adjustably connected according to shoe size for maintaining the device on the foot. It has been found that the most effective location for the device is at the instep of the shoe and a heel band is provided for assuring this location on the users foot. To assure maximum conductive contact with the floor, which would otherwise be limited due to the fact that the conductive tread is being drawn rearwardly and upwardly away from the floor by the securing members, a resilient shoe pad is secured to the upper surface of the tread and bears against the instep of the wearer.
One object of the invention is to provide a conductive 3,379,932 Patented Apr. 23, 1968 foot covering having improved durability in gaseous atmospheres without sacrificing adaptability to various sizes of shoe previously attained by employing elastic shoe bands.
Other objects and advantages of the invention may be appreciated on reading the following detailed description of one embodiment thereof taken in conjunction with the following drawings, in which:
FIG. 1 is a perspective of the foot grounding device on the user,
FIG. 2 is a plan view of the conductive foot covering component of the grounding device, and
FIG. 3 is a partial section on line 3-3 of FIG. 1.
Referring to the drawings, the grounding device is adapted to be fastened to a shoe and to a leg of the wearer for carrying off electrostatic charges from the body of the wearer. The grounding device includes a tread member 10 which is preferably fashioned of resilient material and impregnated with conductive material such as graphite or carbon and which by reason of its resiliency is comfortable to wear. A soft foot pad 12 is secured to the member 10 intermediate its ends and on its top surface. The pad is preferably resilient and when so attached in use is sufficiently thick that together with the member 10 takes up any space that may exist between the instep of the shoe and the floor.
To one end of the member 10 is attached a plastic securing device 14 and to the other end of the member is attached a similar device 16. Neither device has any elasticity and so to provide the necessary adjustability for different size shoes and boots, there is mounted on the free end of the device 14, a buckle 18 which is adapted to receive and secure in place the free end of the device 16. An inelastic heel strap 20 is similarly attached to the member It) being adapted to maintain the member 10 at the instep and against the heel of the shoe.
A conductor 22 is connected to the member ltl at one end thereof. The conductor is connected at its other end to a conductive leg band 24 on which there is mounted a metallic plate 26 which is placed against the skin near the calf of the leg when worn by the user. As in other grounding devices of the general type, the band is adapted to pick up static charges generated by the body which are led off through the device to the floor due to its neutral potential.
The width of the member 1%) may be varied as desired to assure maximum contact at the instep. The efficiency of the grounding device is dependent to some degree on the tension placed on its principal components. Because there are separate securing components tending to urge the conductive tread from the floor support and generally in the direction of the leg band, the tension is apt to be relieved due to these components especially as the Wearers weight is borne by the tread member 10. The pad 12 serves to counteract the effect of the securing components and the weight of the user without sacrificing the security of the device itself nor its adaptability to different users and shoes on which it is worn.
Various modifications of the invention may be effected by persons skilled in the art Without departing from the scope and principle thereof as defined in the appended claim.
What is claimed is:
1. A body grounding device comprising a resilient conductive tread member, a non-conductive and inelastic plastic device connected to one end of said member, a second non-conductive and inelastic plastic device connected to the other end of said member, means for adjusta'bly connecting the free ends of said devices, a foot pad secured to the top surface of said member, and a conductive leg band electrically connected to said tread memher.
4 References Cited UNITED STATES PATENTS 2,287,744 6/ 1942 Monahan 3172 2,745,041 5/ 1956 Price 3172 2,933,651 4/1960 Legge 317-2 MILTON O. HIRSHFIELD, Primary Examiner.
J. A. SILVERMAN, Assistant Examiner.