Abstract:
A rotary plug valve is disclosed having a housing and a valve core which can be selectively locked in an unlimited number of positions relative to the mandatory inlet and outlet piping, said valve having no visible indication of the internally concealed locking mechanism location. Selectively, a locking pin, that can be activated by authorized personnel, is passed through a passageway engaging a concealed locking cap preventing rotation of the valve core relative to the valve housing for security and safety applications. Removal of the locking pin with an authorized key permits operation for conventional usages.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of Invention 
     The present invention relates to a rotary plug valve that not only can be opened to fluid flow or closed to fluid flow but can also be selectively and securely locked-closed to fluid flow. In limited application, an adaptation can make this concept lock-open to fluid flow. 
     2. Description of the Prior Art 
     Since the inception of piping distribution systems and gas systems in particular, it has been necessary to control the opening and closing of gas supply to each location as required and to securely lock the gas supply for safety and to secure property. Externally exposed locks, shields, shrouds, wings, and locking apertures have been easily sawed, hammered, pried, broken, sheared, levered and otherwise tampered with to circumvent the locking security. Internal locking mechanisms have been complicated, such as spring activated plungers, magnets, single operation mechanisms, and mechanisms requiring special tools that may not be available in emergency situations where fire, police, or emergency may have need to secure an installion. 
     An unauthorized turn-on of a gas supply can create a fire, explosion or suffocation at some point downstream of the gas valve, particularly in new projects, in renovations, and in unoccupied buildings. In such locations all appliances may not be completely installed. Branch lines may be temporarily not inspected. Unauthorized turn-on of the gas supply can be disasterous. 
     In cases of non-payment of past due bills, unauthorized turn-on of the gas supply is theft. 
     U.S. Pat. No. 3,560,130, issued Jan. 15, 1968 to this inventor, created a simple and effective internal locking device, whereby the valve housing enshrouded a locking pin such as a gas-industry-utilized Smith-Morse or E.J. Brooks &#34;Barrel&#34; lock. The vulnerable exposed wings were made internal and an internally concealed locking cap secured a standard locking pin. The locking pin that passed through a cavity through the valve housing, through the valve core and locked into the blind locking cap. To create this internally concealed passageway, additional material was added to two sides of the valve housing, creating two protrusions. 
     After over twenty years of usage throughout the United States, millions of valves installed, and thousands of valves attacked, some shortcomings to this device became known. Where headroom or sideroom was limited, necessary access for installing the locking pin may have presented some difficulty Access to installing was limited to a single plane at right angles to the inlet and outlet piping. The extra material needed to create the internal locking pin passageway presented some installation difficulty, but, most significantly, these protrusions gave some indication as to where the valve could possibly be attacked. Although there are no reported cases of gas being stolen because of a failed (after thousands of attempts) valve, the many mutilated valves had to be replaced at some cost. Since the valve was designed to fail-safe, hazards were not created. Determining that an unauthorized gas turn-on had been attempted was generally easy, but efforts to determine who was responsible were not as successful. 
     Some manufacturers of the valves had had problems registering the locking pin through its passageways in the valve core and valve body when the core migrated due to wear on the valve seat. In an attempt to facilitate lining up the holes, those of skill in the art made all the lock pin holes larger, which made the pin more vulnerable to an attack by a puller. 
     SUMMARY OF THE INVENTION 
     The object of this invention is to correct the limitations of the PILFER-PROOF valve of U.S. Pat. No. 3,560,130; namely, to improve access for installing the locking pin, improve clearance for installing the valve, eliminate protrusions, and deter attacks on the valve. Rotating the passageway of the valve housing (including the cap segment) and the valve core 90 degrees eliminates all protrusions. The locking pin passageway becomes parallel to the inlet and outlet piping and in close proximity to it. The outside dimensions of the walls of the locking pin passageway are flush with the two sides and the top (head) of the valve housing, creating a formidable rectangle of material enshrouding the locking pin passageway. The mandatory clearance necessary for installing the inlet and outlet piping is also available for installing the valve and the locking pin. The valve can be installed so that the locking pin passageway is in any of an unlimited number of positions around the circumference of the inlet and outlet piping. Alternatively, the valve can be reversed 180 degrees which makes another 360 degrees available to the locking pin and its passageway on the other side of the valve. An installation position can be optimized to achieve access by utility personnel, to achieve concealment, or to impede vandals from gaining access. 
     The retaining cap may be oriented upstream over the live part of the valve containing live gas; or oriented downstream past the live gas, according to policy. If there is sufficient clearance around the pipes to install the valve, there will be sufficient clearance to access the lock, since both operations require similar clearances. 
     The two side protrusions of the prior valve are eliminated. The profile of the head is lowered. There are no increases in any of the overall dimensions. As a result, clearance is improved in three directions. 
     The rectangular design eliminates any indications as to where the locking mechanism may be located or if and how it can be attacked. Placing the entire valve and locking mechanism in this imposing rectangular block is a deterrent. It is apparent to an attacker that making long and elaborate incisions in close proximity to live gas can be hazardous to the attacker. 
     A color matched dust cap flush to the locking pin entranceway and or a color matched seal, together with an optimum valve positioning installation, could deter an attacker completely. 
     Fitting clearances for aligning the locking pin and passageway are very tight in the housing section but are loose in the internally concealed passageway through the valve core. This eliptical passageway has its long axis in the same plane as the valve head-torque nut axis. When manufactured, the locking pin passageway of the valve housing is made to register on the bottom (gas port side) of the valve core passageway. This permits adjustment (downward) as the valve core reseats in usage and gives vertical clearance for installing the lock. 
     In contrast to the conventional approach of making large clearances in all the passages, the clearance of the cylindrical head of the locking pin with the cylindrical entrance of the locking passageway is reduced. This reduction gives extra protection to the head of the locking pin. 
     The retaining lip of the cap is made perpendicular to the retaining bearings of the locking pin. Thus, bearings are in compression if unauthorized force is placed on the long axis of the locking pin. The locking grooves of the prior art present a more readily circumvented inclined plane if these same unauthorized forces are applied to the prior art locking pin. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     In order that the present invention may be readily carried into effect, it will be described with reference to the accompanying drawings forming a part of the specification, wherein: 
     FIG. 1 is a perspective view showing the valve of the present invention with gas ports in the open position. 
     FIG. 2 is a cross sectional view of FIG. 1 through A--A. 
     FIG. 3 is a perspective view of the valve core. 
     FIG. 4 is a perspective view of the valve housing sectioned through section A--A and all other components (sans dust cap) in perspective view ready for assembly in the locked-closed position when the valve core from FIG. 3 is included. 
     FIG. 5 is a partial section through section A--A showing components in a gas-flow-locked position. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     In the drawings the same components are identified by the same reference numerals. 
     In FIG. 1, valve core 2 (FIG. 2) can be rotated around axis 3 in valve housing 1, the rectangular wrench-operated head 4 of valve core 2 has its longer dimension parallel to the gas ports 5 (FIG. 3) to indicate gas ports open, registering with inlet and outlet piping 7. With valve core 2 thus oriented, locking passageway 9 of valve core 2 (FIG. 2 is not capable of accepting locking pin 10 (FIGS. 4). By rotating valve head 4 (FIG. 3) ninety degrees, whereby gas ports 5 of valve core 2 are perpendicular to inlet and outlet piping 7 (FIG. 5, gas passage is blocked by tapered seating face 15 of valve body 1 (FIGS. 4, 5). Locking pin passageway 8 is aligned and in register with valve core passageway 9 and retaining cap 12 (FIG. 5). For authorized locking off of gas supply a key (not shown) operated locking pin 10 is inserted through locking passageway 8 and 9 and, with the same key, retaining bearings 13 (FIG. 4) are engaged and locked against retaining cap lip 11 (FIG. 4). Said key-operated locking pin can be an industry &#34;Bullet&#34; or &#34;Barrel&#34; lock, as furnished by Smith-Morse or E.J. Brooks, or can be another suitably sized cammed locking cylinder. 
     The key-activated retaining bearings 13 of locking pin 10 are retracted to clear retaining lip 11 (FIG. 2). Removal of the key causes retaining bearings 13 to move outward, thereby engaging the vertical face of retaining lip 11 (FIG. 5). Retaining bearings are placed in compression if unauthorized tensile or compressive force is placed on either end of locking pin 10. Commercially used caps, for more than fifty years, have used a groove for retaining these bearings. Where such a groove was used, unauthorized tensile or compressive force on either end of the lock had but to overcome an inclined plane. In the present invention, unauthorized effort to rotate valve core 2 for illegal turn-on of gas is thwarted as locking pin 10 is placed in shear in two planes on both ends of locking pin passageway 9. If excessive rotating force is placed on valve core head 4, it is designed in to fail-safe, its head shearing off with the valve in a locked-closed position. Authorized removal of locking pin 10 by utility company personnel after payment of past due account, or after an installation is certified as to safety, permits normal usage of the gas supply system. 
     Locking pin passageway 8 and retaining cap 12 are parallel and in close proximity to inlet and outlet piping 7. The same access space for installing the necessary supply piping, including a myriad of fittings, is available for installing the valve. The locking pin passageway can be installed in an unlimited number of positions or orientations around the 360 degree circumference of the inlet and outlet piping. The locking pin is always in the same close proximity, positioned at an optium plane for a particular desired access. The same access available for the inlet and outlet piping 7, and the locking passageway 8 is also available for installing locking pin 10. With the elimination of the protrusions that enveloped the locking passageway of U.S. Pat. No. 3,560,130, the outer dimensions of locking pin passageway 8 and 12 (FIG. 2) in valve housing 1 (FIG. 1) are placed within the existing limits of dimension 16 and 17 (flush block), improving installation clearance. Inlet-outlet piping passageway 7 now shares a common wall of material 19 with locking pin passageway 8, eliminating one wall of material and reducing profile 18 (FIG. 1), thereby reducing material. 
     The locking pin passageway 9 and the gas port 5 of valve core 2 (FIG. 3) are at right angles to each other in this valve-lock-closed configuration. The core is strengthened as there is more material 20 (FIG. 3) in this plane at no increase in material for the complete valve core 2. In the valve-locked-open configuration with parallel ports, the core is weaker. Since the lock-closed configuration is the more vulnerable and more often used configuration (99+ percent), the gain in strength is in the configuration where such gain is most needed. 
     Eliptical locking passageway 9 of valve core 2 has its long (vertical) axis on center line 3. Adjustment of the tapered seating area of valve core 4 and valve housing seating area 15 with adjusting nut 14 permits continual reseating and gas tightness in the manufacture, fitting, and continual future use and wear. The short axis of elipical locking pin passageway 9 of valve core 2 in manufacturing has greater clearance 21 (FIGS. 2 and 5) on the operating head side of valve core 2 and lesser clearance 22 on the gas port side of valve core 2, permitting future reseating adjustment and creating locking pin installation clearance. Cylindrical locking pin passageway 8 and retaining cap 12 are of minimal clearance to locking pin 10, as locking pin passageway 8 and retaining cap 12 are in fixed and identical planes vertically and horizontally. In other words, they share the same line as a central axis. Locking pin retaining cap 12 and head 23 of locking pin 10 are of a diameter which is larger than the short (horizontal) axis of eliptical passageway 9 of valve core 2, to prevent unauthorized removal of locking pin 10 or locking cap 12. 
     With the elimination of all locking pin passageway protrusions and the creation of a formidable rectangular block with some of this material at close proximity to the inlet and outlet piping threads, the design gives no indication as to where or how locking is effected or where should be attacked. The color blended dust cap (seal) 26 FIG. 4 and 5 and multiplicity of locking pin orientations are effective deterrents, as is the hazard of working in the proximity of the inlet and outlet piping, where live gas could be encountered, or of making extensive apertures through extended stretches of material. 
     The valve can be made to lock open for limited control functions by advancing the locking pin passageway 90 degrees in the valve core. It can be made to accept other cylindrical locks with a myriad of keying systems. It can be adapted for water systems, fire hydrants, and other systems where a rotary plug valve needs to be secured.