Directional control valve locking device

An inexpensive, simple, effective, and easily implementable locking device for use with directional control valves that allows for the valve to be securely locked in a desired operating position, thereby preventing unauthorized, inadvertent or otherwise undesired manipulation of the valve minimizing potentially damaging or injurious conditions. The locking device has an adjustable locking plate and a fixed locking bracket, both of which are adapted to the valve using the valve's existing components for ease of installation and adaptation and so the normal operation of the valve is not impeded. The adjustable locking plate is mounted to the valve over the valve stem. The fixed locking bracket mounts to the valve body using the valve's existing bolts and nuts. Locking holes in the adjustable locking plate and fixed locking bracket line up and allow for the valve to be securely locked in a desired operating position with a locking member.

BACKGROUND

The present invention relates to locking devices in general and more particularly to a locking device for directional control valves to protect against the intentional and/or unintentional adjustment of the valve handle from a desired position.

In typical directional control valve systems, whether liquid or gas, the selected operating position of the handle of the valve thereof may be essential to the proper operation and functioning of the system as a whole. The improper positioning of the handle or the intentional or unintentional adjustment of the valve handle may result in a complete malfunction of the system, often with serious and dangerous consequences. Accordingly, it is often desirable to securely lock directional control valves at one or more desired operating positions to prevent intentional tampering and unauthorized or otherwise inadvertent manipulation of the valve handle from the desired operating position.

Directional control valves are commonly used for general purpose and heavy-duty industrial applications. It is desirable to secure or lock valves in a desired operating position in nearly all applications. Unfortunately, tampering with industrial operations is often a great temptation to certain people, or organizations, by unauthorized manipulation of the valves to interrupt or interfere with industrial productions. Alternatively, unauthorized manipulation of valves can simply be the result of inadvertent misuse or accidental mistakes. Occupational health and safety organizations, such as the Occupational Safety and Health Administration (OSHA) and other workplace and industrial oversight organizations, advocate more control over the operation of directional control valves. The ability to securely lock directional control valves in the desired operating positions avoids many, if not all, of the described problems, which in turn avoids potential catastrophic and/or injurious conditions in industrial and other settings.

Many of the known valve locking devices are expensive, complex, difficult to manufacture and install, interfere with the normal operation of the valve, and require many parts in order to be adapted to a valve. Because of this, field personnel often improvise and hastily create a roughly constructed, makeshift mechanism to lock a valve in its desired position. The inadequacy of the makeshift mechanism often leads to unsafe conditions. For example, an extremely important safety procedure in many industries, the oil and gas industry for example, is the “lockout/tagout” procedure to ensure workers remain safe while servicing or repairing equipment by making it physically impossible to change the desired operating position. An effective locking device for valves during “lockout/tagout” is important to prevent unsafe conditions. Failure of having an adequate locking device could lead to property damage, serious injury or death.

For the foregoing reasons, there is a need for a relatively inexpensive yet secure, simple, effective and easily implemented locking device for valves which may be virtually universally adapted for mounting and operation on almost all conventional directional control valves for use in any number of applications and/or environments to prevent the unauthorized, inadvertent or otherwise undesired manipulation of directional control valves from a desired operating position.

SUMMARY

The present invention is directed to a locking device for directional control valves that satisfies the foregoing needs. The locking device according to this invention provides an economical and easily implemented solution for the secure locking of directional control valves in the desired operating position. Such a device according to this invention cannot be easily defeated, destroyed or otherwise removed without authorization. Therefore, the locking device of the present invention prevents the unauthorized, inadvertent or otherwise undesired manipulation of directional control valves from their desired operating position, thereby minimizing, if not entirely eliminating, the likelihood for damage or injury in an industrial or other setting.

A locking device having features of the present invention comprises an adjustable locking plate and a fixed locking bracket designed to be installed on directional control valves using the valve's existing parts for ease of installation and so as not to interfere with the normal operation of the valve. The adjustable locking plate of the present invention replaces the valve's existing ball detent travel stop plate. The adjustable locking plate retains the use of the valve's stem, stem bushing, lever handle, stem washer, and stem nut. The adjustable locking plate is installed on the existing stem of the valve underneath the stem bushing, which separates the adjustable locking plate from the control lever handle, and affixed to the valve by the stem washer and stem nut. The adjustable locking plate incorporates the features found on the valve's existing ball detent travel stop plate, which include the ball detent holes and travel stop hole. The ball detent holes in combination with the ball detents of the valve aid in the adjustment of the valve lever handle to the different operating positions. The travel stop hole also aids in this adjustment and limits the movement of the valve lever handle. Additionally, the adjustable locking plate has at least three spaced apart locking holes therein. The fixed locking bracket of the present invention consists of a mounting portion and locking portion. The mounting portion of the fixed locking bracket has at least two holes designed to be mounted to the valve using the valve's existing bolts, lock washers and nuts. The locking portion of the fixed locking bracket has at least 3 spaced apart locking holes. The locking holes of the adjustable locking plate and fixed locking bracket are spaced apart so that they align with each other depending on the position of the directional control valve's control lever handle. A lock or other locking means can then be inserted through the aligned locking holes of the adjustable locking plate and fixed locking bracket to securely lock the directional control valve in the desired position to prevent the unauthorized, inadvertent or otherwise undesired manipulation of the directional control valve, thereby increasing the security and safety of the directional control valve and systems utilizing them.

While it is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive on the present invention, these and other features, aspects, and advantages of the present invention will become better understood with regard to the following detailed description and accompanying drawings where:

DESCRIPTION

Referring now to the drawings, reference will be made to the preferred embodiment of the invention, an example of which is illustrated in the accompanying drawings and not meant for purposes of limited the scope of the present invention. With reference toFIG. 1, it is generally shown a directional control valve1to which a locking device20of the present invention is installed thereon. Although the preferred embodiment has been developed for the directional control valve1, it is shown for purposes of merely illustrating the present invention and it is within the scope of the present invention to adapt the locking device to any valve or other device controlled by an operating member or handle rotating between any number of controlled positions. However, as disclosed herein, the valve used with the preferred embodiment of the present invention comprises the directional control valve1having a stem19protruding outwardly from the valve body on which an adjustable locking plate9and a valve lever handle8are mounted. The adjustable locking plate9and a valve lever handle8are separated from each other by a stem bushing7and all affixed to the valve stem19by a stem washer6and a stem nut5. In the preferred embodiment, the valve lever handle8, stem bushing7, stem washer6and stem nut5are existing components of the valve1. A fixed locking bracket10is affixed to the valve body using existing bolts2, lock washers3, and nuts4of the valve.

The locking device20of the present invention is better illustrated inFIGS. 2A-3Cand in, the preferred embodiment, is generally comprised of two, separate component parts, namely, the adjustable locking plate9and fixed locking bracket10. The adjustable locking plate9has a stem slot18for receiving the stem19of the valve for mounting and installation and adopts the ball detent holes21and travel stop22that are part of original valve ball detent travel stop plate so that the adjustable locking plate9retains the use of the valve's ball detents and travel stop, thereby not interfering with the normal operation of the valve1. Further, the adjustable locking plate9has locking holes15,16, and17, each of which correspond to a different desired operating position of the valve wherein the valve may be securely locked in said position. The fixed locking bracket10is comprised of a mounting portion25and a locking portion24, wherein the mounting portion25has two mounting holes23so that the fixed locking bracket can be affixed to the valve using the existing bolts2, lock washers3, and nuts4of the valve, and the locking portion has three locking holes12,13, and14, each of which correspond to a different desired operating position of the valve and also align with the locking holes15,16, and17of the adjustable locking plate9at the desired operating positions. The locking portion24is in a plane generally higher than the plane of the mounting portion25, that is the locking portion24is in a plane close to the top of the valve1, while the mounting portion25is in a plane closer to the middle of the body of the valve1. It is possible for alternative embodiments for use with other types of valves or apparatuses in difference environments to have more or less locking holes and to have them spaced differently than in the preferred embodiment. The adjustable locking plate9and fixed locking bracket10are preferably constructed from A36 carbon steel and yellow zinc plated, but of course can be made of other advantageous materials without departing from the intent or scope of the present invention.

As is shown inFIGS. 4A and 4B, when the valve lever handle8is in a first position of operation, locking hole15of the adjustable locking plate9is perfectly aligned above locking hole14of the fixed locking bracket10. As is shown inFIGS. 6A and 6B, if the first position of operation of the lever handle is the desired position of the directional control valve1, then a padlock11, or other means of locking, can be passed through the aligned locking holes15and14so as to securely lock the valve in this desired operating position.

FIGS. 5, 7A and 78Bshow the directional control valve1locked in a second position of operation of the valve lever handle S. As is shown, when the directional control valve1is in the second position of operation, locking hole16of the adjustable locking plate9is perfectly aligned above locking hole13of the fixed locking bracket10. A padlock11, or other locking means, can then be passed through the aligned locking holes13and16so as to securely lock the directional control valve in this desired position.

As is shown inFIGS. 8A and 8B, when the valve lever handle8is in a third position of operation, locking hole17of the adjustable locking plate9is perfectly aligned above locking hole12of the fixed locking bracket10. If the third position of operation of the valve lever handle8is the desired position of the valve1, then a padlock11, or similar means of locking, can be passed through the aligned holes12and17so as to securely lock the valve in this desired position.

While the locking device has been described with reference to a directional control valve, it will be appreciated that other valve types as well as other structures and apparatus having a rotatable operating member could also utilize the subject device. While some modifications to the subject locking device may be necessary for adapting to a specific valve or apparatus or operational environment, the above description of the preferred embodiment is deemed sufficient to permit those skilled in the art to practice the concepts of the present invention. Further, it is within the ambit of the present invention to cover any obvious modifications of the preferred embodiment described herein.