US3572795A

US3572795A - Tamper resistant seal

Info

Publication number: US3572795A
Authority: US
Inventors: James Y Howard; Loren R Springett
Original assignee: General Signal Corp
Current assignee: SPX Corp
Priority date: 1969-11-25
Filing date: 1969-11-25
Publication date: 1971-03-30
Anticipated expiration: 1988-03-30
Also published as: CA959243A

Abstract

A tamper resistant seal for restricting access to a removal fastener in a receptacle has been provided. A loose fitting removal insert lodged in the receptacle covers the cross section of the receptacle and fastener and a sealing member passing through a hole in the sidewall of the receptacle and at the cross section of the receptacle restricts the removal of the insert and the sealing member must be broken to give access to the fastener.

Description

United States Patent 315, 205, 316, 317, 318, 319, 320, 321, 322, 323, 324, 325, 326,198,251;70/440,176,2, 177; 220/39 (A); 217/56; 24/(1nquired); 85/(1nquired) IAN Il/lllllllllllll! [56] References Cited UNITED STATES PATENTS 255,313 3/1882 Mayer 292/251 837,789 12/ 1 906 Brooks 292/ 307 1,612,420 12/1926 Davis..... 292/307 2,084,963 6/1937 Paige..... 292/307 2,772,109 11/1956 Busch 292/307 Primary Examiner-Stephen .l. Novosad Assistant Examiner-Edward J. McCarthy Attorneys-Harold S. Wynn ABSTRACT: A tamper resistant seal for restricting access to a removal fastener in a receptacle has been provided. A loose fitting removal insert lodged in the receptacle covers the cross section of the receptacle and fastener and a sealing member passing through a hole in the sidewall of the receptacle and at the cross section of the receptacle restricts the removal of the insert and the sealing member must be broken to give access to the fastener.

TAMPER RESISTANT SEAL BACKGROUND OF THE INVENTION This invention relates to sealing devices and in particular to tamper resistant devices which must be destroyed before access can be had to fasteners and the like.

It is sometimes necessary to provide a sealing device for access covers to safety equipment such as relays or metering equipment and the like. In certain types of apparatus, the sealing device will, if broken, give a warning that the apparatus enclosed was tampered with and that such apparatus must be adjusted again or removed and repaired. Under these conditions, it is not always necessary to make the seal a permanent part of the apparatus housing. For example, it is possible to seal a cover with a rivet and removal of the rivet by drilling or punching enables a person to gain access to the cover. In other situations, a screw-type fastener may be inserted in a receptacle and the head of the screw covered with a wax and suitably sealed with some code or the initials of some authorized person. Such a coded indication means that the person sealing the screw head was authorized to do so. In order to remove a wax seal and the like from such a receptacle, it is necessary to drill out or gouge out the wax which may at times be a very difficult and time consuming operation. However, this may be necessary because not only is the seal for providing a warning that some unauthorized person has entered the housing, but also it is to retard or at least restrict access to the head of the screw so that the screw may not be backed off somewhat and limited access gained to the inside of the housing which is possible in some cases. In other words, it may be possible to gain access in some instances to the housing without breaking the seal thereby frustrating the purpose of the seal in the first place and secondly not giving a warning that the apparatus has been tampered with and thus may result in some damage to periphery equipment which this apparatus may be protecting.

It is therefore an object of this invention to provide a tamper resistant seal for restricting access to a removable fastener recessed in a receptacle and for alleviating the aforementioned problems, with a simple and easily installed device.

It is another object of this invention is to provide a seal which is easily removed by authorized personnel but when removed by unauthorized personnel gives a warning that the apparatus has been tampered with.

The foregoing and other objects and advantages of this invention will become apparent from the following description when taken and read in conjunction with the accompanying drawings, in which:

FIG. 1 is a top elevation of a housing to be protected by the seal with the seal in place;

FIG. 2 is a side section elevation of the FIG. 1 along line 2-2; and

FIG. 3 is an alternate configuration of the preferred embodiment of the present invention.

SUMMARY OF THE INVENTION There has been provided a tamper resistant seal for restricting access to a removal fastener recessed in a receptacle including a loose fitting removal insert lodged in a receptacle for substantially covering the cross section of the receptacle and the fastener. A sealing member passing through a hole in the sidewall of the receptacle and out of the cross section of the receptacle sealed upon itself and the presence of the sealing member restricts the removal of the insert so that the sealing member must be broken to give access to the fastener thereby giving warning of unauthorized access to the fastener.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The apparatus of the present invention is employed in order to provide a simple and easily detected unauthorized access to a restricted housing. FIGS. 1 and 2 show top and side views respectively of the housing and the apparatus used in the present invention. The housing includes the base 1 and a cover section 2 containing apparatus to which access must be restricted to only authorized personnel. A screw 3 is fitted into tapped hole 4 in base 1 and through counterbore or receptacle 5 of the cover 2. A ball 6 is inserted over the top of screw 3 so that a screwdriver or other suitable tool for removing the screw may not be used to gain access to the head of the screw 3. A sealing member is then inserted over the ball 6 for preventing the removal of the ball 6. This sealing member in cludes a top ball 7 with a tab wire 8 attached thereto and a hole 9 passing through the top ball 7. Tab wire 8 is fitted through a hole 10 in the counterbore 5 and then passed through hole 9 in the ball 7 itself for sealing. Once the tab wire is drawn tightly through hole 10 and sealed, it is impossible to remove ball 6 and gain access to the screwhead 3 without snapping or breaking the tab wire 8 thus giving notice to any one who checks the seals that the apparatus may have been tampered with.

It can be readily seen from this that it is no longer necessary to seal the receptacle or counterbore 5 with the sealing wax and the like. All that is necessary now is to insert the ball 6 into the counterbore 5 which prevents any tool from being inserted into the counterbore 5 for backing off screw 3. Thus, the protection to the apparatus is sustained because unauthorized access will be readily detected. As previously mentioned, the use of sealing wax has made it difficult to gain access to the apparatus in the housing and may require complete removal for repairs at a later time. Replacement of the apparatus and the housing because of the excess time required for repairing the housing is often expensive and with the disclosure of the present invention may be unnecessary because access by authorized personnel is quite readily achieved.

An alternate application of the concept of the present invention may be observed with respect to FIG. 3. Instead of using a separate sealing member and ball member, for restricting access to the counter bore 5, a cylinder 11 may be used having a tab wire 12 which is passed through the hole 10 in the counterbore 5 as shown and then sealed on itself at 13 by some suitable sealing member of the like. This device similarly prevents access to the screwhead 3 and also must be destroyed or clipped to be removed. In this way, the detection of unauthorized access to the apparatus has been detected but the authorized entrance may be readily achieved.

While there has been described what is at present considered to be the preferred embodiments of the present invention, it will be obvious to those skilled in the art that various changes and modifications may be made therein without departing from the true scope of the present invention.

We claim: 1. A tamper resistant seal for restricting access to a removal fastener recessed in a receptacle comprising:

a loose fitting removable insert lodged in said receptacle for substantially covering the cross section of said receptacle and fastener; and a a sealing member passing through a hole in a sidewall of the receptacle and out the cross section of said receptacle such that once sealed, the presence of the sealing member restricts the removal of said insert whereby the length of sealing member must be broken to give access to the fastener.

2. The seal of claim 1 wherein the insert is of spherical shape.

3. The seal of claim 1 wherein the sealing member comprises a tab relatively larger than the receptacle, said tab having a hole therein; and a length of scalable material attached to said tab at one end for passing through the cross section and hole in the sidewall of the receptacle and through the hole in the tab for sealing.

4. A tamper resistant seal for restricting access to a removable fastener recessed in a receptacle comprising:

a loose fitting removable insert lodged in said receptacle substantially covering the cross section of the receptacle, with one end adjacent to the fastener; and

a length of sealable material attached to the other end of said insert passing through a hole in the sidewall and the cross section of the receptacle for sealing on itself for preventing unauthorized access to said fastener.

Claims

1. A tamper resistant seal for restricting access to a removal fastener recessed in a receptacle comprising: a loose fittinG removable insert lodged in said receptacle for substantially covering the cross section of said receptacle and fastener; and a sealing member passing through a hole in a sidewall of the receptacle and out the cross section of said receptacle such that once sealed, the presence of the sealing member restricts the removal of said insert whereby the length of sealing member must be broken to give access to the fastener.

2. The seal of claim 1 wherein the insert is of spherical shape.

3. The seal of claim 1 wherein the sealing member comprises a tab relatively larger than the receptacle, said tab having a hole therein; and a length of sealable material attached to said tab at one end for passing through the cross section and hole in the sidewall of the receptacle and through the hole in the tab for sealing.

4. A tamper resistant seal for restricting access to a removable fastener recessed in a receptacle comprising: a loose fitting removable insert lodged in said receptacle substantially covering the cross section of the receptacle, with one end adjacent to the fastener; and a length of sealable material attached to the other end of said insert passing through a hole in the sidewall and the cross section of the receptacle for sealing on itself for preventing unauthorized access to said fastener.