Abstract:
A mechanism used for locking a valve that provides positive control of the valve lock to prevent the valve from changing position unintentionally is disclosed. The positive locking valve control device preferably includes a housing with a handle and a linkage extending therefrom. A main gear inside the housing is disposed about a shaft which is positionally fixed outside of the housing. The main gear is releasably intermeshed with a locking gear controlled by the handle. Squeezing the handle separates the gear and allows angular movement of the handle which corresponds to movement of the linkage. The linkage is connected to a valve actuator or valve stem and the position of the valve may be adjusted in this manner. Springs in the handle cause the main gear and locking gear return to a locked position when the handle is released. Accordingly, the valve cannot drift or be bumped out of position when the handle is released.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims the benefit of U.S. Provisional Patent Application Ser. No. 60/913,040, filed Apr. 20, 2007, the disclosure of which is hereby incorporated by reference. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention relates to valve control devices, and more particularly relates to a positive locking valve control device with a squeeze trigger that may prevent unintended movement of the valve. 
       BACKGROUND INFORMATION 
       [0003]    Top mount controls are used to open and close water valves. Such devices are particularly suited for use with water valves located on vehicles such as fire trucks in order to prevent the valve from changing position unintentionally while it is either in use or awaiting use. However, conventional top mount controls tend to slip, causing the valve position to change unintentionally. 
         [0004]    U.S. Pat. No. 6,568,654, which is incorporated herein by reference, discloses a positive locking valve control device which includes a push-pull rod having a toothed configuration that is engaged at different positions by a spring mechanism on the valve locking device in order to hold the push-pull rod and thereby the valve securely in place. This configuration is often used to provide a side mounted control for a water valve on a fire truck. However, the push/pull nature of this control device is better suited for a side mount control than for a top mount control. 
         [0005]    A need exists for a valve locking mechanism that provides positive control of the valve lock. A need also exist to provide a valve locking mechanism that is easily controlled from a top mount configuration. 
         [0006]    The present invention has been developed in view of the foregoing. 
       SUMMARY OF THE INVENTION 
       [0007]    The present invention provides a mechanism used for locking a valve that provides positive control of the valve lock to prevent the valve from changing position unintentionally. The positive locking valve control device preferably includes a housing with a handle and a linkage extending therefrom. A main gear inside the housing is disposed about a shaft which is positionally fixed outside of the housing. The main gear is releasably intermeshed with a locking gear controlled by the handle. Squeezing the handle separates the gear and allows angular movement of the handle which corresponds to movement of the linkage. The linkage is connected to a valve actuator or valve stem and the position of the valve may be adjusted in this manner. Springs in the handle cause the main gear and locking gear to return to a locked position when the handle is released. Accordingly, the valve cannot drift or be bumped out of position when the handle is released. 
         [0008]    An aspect of the present invention provides a valve locking device comprising a housing containing a main gear coupled to a shaft projecting from the housing; a linkage extending from the housing in a first direction; a first rod having a first end connected to the housing and a second end extending from the housing in a second direction; a handle assembly connected the second end of the outer rod, the handle assembly comprising a handle top and a handle bottom; a second rod connected at a first end to the handle assembly and connected at a second end to a locking gear, the second rod adjacent with the first rod and the locking gear intermeshed the main gear, whereby the angular movement of the housing relative to the shaft is restricted; wherein pressure applied to the handle assembly separates the locking gear from the main gear permitting movement of the housing relative to the shaft. 
         [0009]    These and other aspects will become more apparent from the following description. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0010]      FIG. 1  is an isometric view of the left side of the valve control device according to one embodiment of the present invention. 
           [0011]      FIG. 2  is an isometric view of the right side of the valve control device according to one embodiment of the present invention. 
           [0012]      FIG. 3  is a right side view of the valve control device showing some of the internal components of the device according to one embodiment of the present invention. 
           [0013]      FIG. 4  is a front view of the valve control device of  FIG. 3  showing some of the internal components of the device according to one embodiment of the present invention. 
           [0014]      FIG. 5  is a cross sectional view of the valve control of  FIG. 4  along section line  5 - 5 . 
           [0015]      FIG. 6  is left side partial sectional view showing the interior components of the valve control device with the teeth of the main gear intermeshed with the teeth of the locking gear according to one embodiment of the present invention. 
           [0016]      FIG. 7  is left side partial sectional view showing the interior components of the valve control device with the teeth of the locking gear separated from the teeth of the main gear according to one embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0017]    For purposes of the following detailed description, it is to be understood that the invention may assume various alternative variations and step sequences, except where expressly specified to the contrary. Moreover, other than in any operating examples, or where otherwise indicated, all numbers expressing, for example, quantities of ingredients used in the specification and claims are to be understood as being modified in all instances by the term “about.” Accordingly, unless indicated to the contrary, the numerical parameters set forth in the following specification and attached claims are approximations that may vary depending upon the desired properties to be obtained by the present invention. At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claims, each numerical parameter should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques. 
         [0018]    Also, it should be understood that any numerical range recited herein is intended to include all sub-ranges subsumed therein. For example, a range of “1 to 10” is intended to include all sub-ranges between (and including) the recited minimum value of 1 and the recited maximum value of 10, that is, having a minimum value equal to or greater than 1 and a maximum value of equal to or less than 10. 
         [0019]    In this application, the use of the singular includes the plural and plural encompasses singular, unless specifically stated otherwise. In addition, in this application, the use of “or” means “and/or” unless specifically stated otherwise, even though “and/or” may be explicitly used in certain instances. 
         [0020]    The present invention provides a valve control mechanism that provides positive control of the valve actuator to prevent the valve from changing position unintentionally. In certain respects, the valve control mechanism is well suited to be used as top mount water valve control on a fire truck. However, in other respects the valve control device may be used to control many different valves in numerous locations, e.g., any water or gas valve adapted to be actuated by the linkage of the valve control device. 
         [0021]      FIGS. 1 and 2  show isometric views of the left and right hand sides of a valve control device  10 , respectively, according to one embodiment of the present invention. The valve control device  10  has a central housing  20  which holds main gear  30 . Attached to and extending from the housing  20  is a linkage  40 . As used herein, the term “linkage” refers to a mechanical linkage which is a series of rigid links connected with joints to form a closed chain, or a series of closed chains. The linkage  40  shown in the embodiments of  FIGS. 1-7  described herein illustrates the first in the series of two or more rigid links. It will be appreciated by one skilled in art that the movement of the linkage at this first link can be translated into countless outputs by additional rigid links connected by joints. In one embodiment, the linkage  40  connects to a valve stem which spans from outside of a valve body (not shown) to inside the valve body or other valve part, thereby transmitting motion of the linkage which controls the internal workings of the valve, for example, movement of a gate or globe. Linkage  40  may also have an aperture  42  or other arrangement for connecting the linkage to the valve. In one embodiment, the linkage  40  connects to another member which is then connected to the valve. The housing  20  may have a cover  50  held in place by cover screws  52 . The cover  50  allows access to the interior of the housing  20 . 
         [0022]    Also extending from and connected to the housing  20  is outer rod  60 . It should be appreciated that the outer rod  60  and linkage  40  extend from the housing  20  in different directions. It should further be appreciated that main gear  30  is centered about a central longitudinal axis  2 . Attention is drawn to the fact that outer rod  60  and linkage  40  extend not only from the housing  20  but, more particularly, extend radially from the central longitudinal axis to the main gear  30 . In this manner, angular rotation of the outer rod  60  causes similar angular rotation of the linkage  40 . For example, in the embodiment shown, linkage  40  and outer rod  60  are each lie in a plane generally perpendicular to the longitudinal axis  2  and arranged approximately 140° apart. This angle may be any angle capable of translating rod  60  movement into suitable movement of the linkage  40  within the valve body. 
         [0023]    Still referring to  FIGS. 1 and 2 , it can be seen that outer rod  60  is connected at one end to the housing  20 . A set screw  22  may be used to hold the outer rod  60  within housing  20 . At its other end, the outer rod  60  is connected to the handle assembly  70 . The handle assembly  70  includes a bottom handle  80  and a top handle  90 . Bottom handle  80  is attached to an inner rod (not shown) by way of roll pins  82 . The top handle  90  is secured to the outer rod  60  by way of a retention screw  92 . The top handle  90  may also have a label area  94  recessed in its outer surface providing a convenient location to label the valve controlled by device  10  with appropriate indicia. The handle assembly  70  is configured to allow a person to grip the handle assembly  70  with one hand and squeeze the bottom handle  80  and top handle  90  so that bottom handle  80  and top handle  90  move with respect to one another. In the embodiment described herein, the bottom handle  80  is pulled into top handle  90  which releases housing  20  to move freely about the main gear  30  and its corresponding central longitudinal axis  2 . As a consequence, linkage  40  also moves and adjusts the valve position. Ergonomic contours  86  may be provided on the exterior of bottom handle  80  to allow easier gripping of the handle assembly  70 . 
         [0024]    Referring now to  FIGS. 3-5 , the interior components of the valve controlled device  10  according to the embodiment shown in the  FIGS. 1-2 . The main gear  30  comprises a shaft  32  which may have holes  34  therein. The main gear  30  also has a center section  36  which is located within the housing  20 . The center section  36  has teeth about its circumference. As used herein, the phrase “main gear” refers to a toothed wheel that engages another toothed mechanism. The housing  20  has cover screw holes  54  for receiving cover screws  52 . The handle assembly  70  is equipped with springs  100  located between the bottom handle  80  and the top handle  90 . As used herein, the term “spring” refers to a flexible elastic object used to store mechanical energy. The spring may be any suitable type, e.g., cantilevered, coiled, compression, tension or leaf. Springs  100  apply pressure which keeps bottom handle  80  and top handle  90  separated. An inner rod  110  is coaxially located within outer rod  60 . Inner rod  110  is connected to the bottom handle  80  by roll pins  82 . Bottom handle boars  84  align with inner handle boars  112  to define roll pin boars  86  through which the roll pins pass. It should be noted that while roll pins and other mechanical fastening means were described herein, any suitable fasteners may be used. Similarly, although springs  100  are shown, any resilient number capable of applying, constant pressure may be used. Each roll pin  82  also passes through a slot  62  in the outer rod  60 . Slots allow axial movement of the roll pins within the length of the slot  62 . Accordingly, movement of the bottom handle  80  is translated into movement of the inner rod  110 . A locking gear  130  is affixed to the end of the inner rod  110  closest to the main gear  30 . As used herein, the phrase “locking gear” refers to a toothed mechanism. Hence, locking gear  130  is also located within the housing  20 . 
         [0025]    Referring now to  FIGS. 6 and 7 , a description of the use of valve control device  10  will be described.  FIG. 6  illustrates a partial view of the interior of the valve closing device in a locked or non-rotational position. The non-rotational or locked position is the normal condition when no force is applied to the handle  70 . The inner rod  110  is fully extended into the housing  20  so that the teeth  132  of the locking gear  130  intermesh with the teeth  38  of the main gear  30 . It follows that due to the intermeshing of the teeth  38 ,  132 , when the mounting holes  34  of the main gear shaft  32  which are arranged external to the housing  20  are secured onto an external frame of a mounting apparatus (not shown), the housing  20 , outer rod  60  and linkage  40  will also be held in a fixed position. 
         [0026]    Referring now to  FIG. 7 , the configuration of the valve control device  10  in the unlocked or rotating configuration, is shown. When bottom handle  80  is depressed into top handle  90 , the bottom handle  80  acts on roll pins  82  which, in turn, act on inner rod  110 . Inner rod  110  moves axially toward the handle assembly  70  which disengages locking gear  130  from main gear  30 . This allows a tangential force applied to the handle assembly  70  to cause angular motion of the housing  20  along with the components attached to the housing  20  about the central longitudinal axis  2  of the main gear  30 . The angular movement of the handle assembly  70  and the corresponding movement of the linkage  40  causes adjustment of the connected valve stem (not shown) and continues until the desired valve position is achieved. Once the appropriate valve setting is reached, the bottom handle is released, returning the locking gear  130  to its inner-meshed position with main gear  30 . In the locked position, undesired drifting of the valve or unintended movement of the handle assembly  70  is prevented. 
         [0027]    Whereas particular embodiments of this invention have been described above for purposes of illustration, it will be evident to those skilled in the art that numerous variations of the details of the present invention may be made without departing from the invention as defined in the appended claims.