Abstract:
A solenoid valve has a valve body with an inlet, an outlet and a valve chamber therebetween. A valve member is selectively engagable with the valve chamber for controlling the flow of fluid from the inlet to the outlet. A solenoid assembly is mounted upon the valve member for moving the valve member to control the flow of fluid from the inlet to the outlet. The solenoid assembly includes a solenoid and a frame for holding the solenoid. The solenoid assembly is connected to the valve body such that the frame is rotatable and slidable away from the valve body to permit access to and slidable removal of the solenoid from the valve member.

Description:
FIELD OF THE INVENTION 
       [0001]    This invention relates generally to solenoid operated, liquid dispensing valves and, more particularly, pertains to improvements in a solenoid mounting arrangement for such valves. 
       BACKGROUND OF THE INVENTION 
       [0002]    Solenoid valves are commonly used to control the flow of infusion water or liquid in hot beverage machines. The typical solenoid valve of this type includes a valve body that defines a valve chamber, and an inlet and an outlet that communicate with the valve chamber. A valve seat is interposed between the inlet and the outlet, and a solenoid operated valve member is adapted to engage the valve seat to permit and prevent flow to the outlet. In the conventional valve, the valve member is biased to a closed position by a spring, and operation of a solenoid will move the valve to an open position. 
         [0003]    U.S. Pat. No. 6,684,901, issued Feb. 3, 2004, and assigned to the assignee of this application, discloses a modular liquid dispensing valve assembled by twisting and untwisting certain valve components into and out of a snap fit without the use of tools and fasteners. In such valve, the solenoid or coil is held in position by a C-shaped frame. A bottom plate of the frame is formed with a plurality of recesses for receiving tang ramping surfaces of locating pins on a snap plate attached to a valve body. The ramping surfaces are snap fit against walls the frame recesses so that the frame, the solenoid and the snap plate form a tightly joined subassembly. This subassembly does not permit an easy disassembly of the frame of the solenoid. Other solenoid mounting arrangements exist which require the use of tools and fasteners to couple and uncouple the frame and the solenoid. Such prior art solenoid mounting arrangements create drawbacks in servicing installed liquid dispensing valves, particularly in the replacement of a solenoid. 
         [0004]    It would be desirable to provide a solenoid valve with a solenoid mounting arrangement in which the frame and the solenoid are easily assembled and disassembled on an installed valve body using rotary and sliding motions and a frictional fit. It would also be desirable to provide a solenoid mounting arrangement which does not require tools and fasteners. Likewise, it would be desirable to provide a solenoid valve wherein the frame and the solenoid are cooperatively moved together and adjustably positioned relative to the valve body. 
         [0005]    The present invention relates to a solenoid valve having a valve body with an inlet, an outlet and a valve chamber therebetween. A valve member is selectively engagable with the valve chamber for controlling flow of fluid from the inlet to the outlet. A solenoid assembly is mounted upon the valve member for moving the valve member to control the flow of fluid from the inlet to the outlet. The solenoid assembly includes a solenoid and a frame for holding the solenoid. The solenoid assembly is connected to the valve body such that the frame is rotatable and slidable away from the valve body to permit access to and slidable removal of the solenoid from the valve member. 
         [0006]    The frame and the solenoid have cooperating structure preventing rotation of the solenoid relative to the frame. The frame has a bottom end plate, a top end plate and a connector plate joining the bottom end plate and the top end plate. The bottom end plate has a depending nib which is engagable with wall structure on the valve body. The bottom end plate and the top end plate are formed with U-shaped slots defined by a pair of spaced apart bottom arms and a pair of spaced apart top arms. The solenoid has an upper surface formed with stop structure engagable with the top arms of the frame. The solenoid assembly includes a backstop member engagable with the top arms of the frame. The backstop member is biased upwardly against the top arms of the frame by spring structure. The bottom arms of the frame are engagable about an upstanding portion of the valve body that encircles the valve member. The frame is slidable away from the solenoid by pressing downwardly on the backstop member against the force of the spring structure. 
         [0007]    In another aspect of the invention, a solenoid operated liquid dispensing valve includes a valve body having an inlet and an outlet for respectively introducing liquid into and delivering liquid out of the valve body. A valve member is selectively movable relative to the valve body for controlling a flow of liquid from the inlet to the outlet. A solenoid assembly is mounted upon the valve body for selectively moving the valve member. The solenoid assembly includes a solenoid slidably mounted on the valve member and a frame for holding the solenoid, wherein the frame is separable from the solenoid without the use of tools and fasteners. 
         [0008]    The valve body includes a snap plate having an upper surface formed with a series of spaced apart cavities having walls for positioning the frame. A cylindrical neck rises from the upper surface of the snap plate in the center thereof for receiving a portion of the valve member therethrough, the neck being formed with a number of outwardly projecting retaining elements. The frame has a bottom end plate, a top end plate and a connector plate joining the bottom end plate and the top end plate. The bottom end plate has a depending nib that is engagable with the wall of any of the cavities formed in the snap plate. The bottom end plate of the frame has a pair of spaced apart bottom arms that are frictionally engagable between the upper surface of the snap plate and the retaining elements on the neck. The solenoid assembly includes an upwardly biased tubular backstop member that extends through a center of the solenoid and slidably receives an upper portion of the valve member. A coil spring extends between a top end of the backstop member and the upper portion of the valve member. The top end of the backstop member is formed externally as a spool having a head, a base and a body connecting the head and the base. The top end plate of the frame has a pair of spaced apart top arms that are slidably engagable between the head and the base of the backstop member. The top arms of the frame are engagable against the base of the backstop member. 
         [0009]    The frame and the solenoid are rotatable together on the snap plate such that the nib on the frame will travel along the walls of the cavity in the snap plate to a predetermined position whereat downward pressure on the head of the backstop member will enable the frame to be slidably pulled and removed from the snap plate, after which the solenoid may be slidably removed from the valve member. 
         [0010]    The invention also contemplates a method of disassembling of solenoid valve to permit servicing thereof. The method includes the steps of (a) providing a valve body having an inlet and an outlet for respectively introducing liquid into and delivering liquid out of the valve body; (b) providing a valve member selectively movable relative to the valve body for controlling flow of liquid from the inlet to the outlet; (c) providing a solenoid assembly movably mounted on the valve body for selectively moving the valve member, the solenoid assembly including a solenoid in a frame for holding the solenoid therein; (d) moving the frame and the solenoid together relative to the valve body to a predetermined position thereon; (e) slidably pulling the frame away from the valve body and the solenoid; and (f) slidably pulling the solenoid upwardly away from the valve member. The steps (d), (e), and (f) are performed without the use of tools and fasteners. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]    The drawings illustrate the best mode presently contemplated of carrying out the invention. In the drawings: 
           [0012]      FIG. 1  is a top isometric view of a solenoid operated, liquid dispensing valve having a solenoid mounting arrangement shown in an operating position; 
           [0013]      FIG. 2  is a view like  FIG. 1  showing the solenoid mounting arrangement rotated to a servicing position; 
           [0014]      FIG. 3  is a view like  FIG. 2  showing removal of the solenoid frame; 
           [0015]      FIG. 4  is a bottom isometric view of the solenoid frame; 
           [0016]      FIG. 5  is a view like  FIG. 3  showing the removal of the solenoid; 
           [0017]      FIG. 6  is a plan view of  FIG. 2 ; 
           [0018]      FIG. 7  is a plan view of  FIG. 1 ; and 
           [0019]      FIGS. 8-10  are sequential partial diagrammatic views showing the replacement of the solenoid frame. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0020]    Referring now to the drawings, there is shown a solenoid operated, liquid dispensing valve  10  embodying the present invention. Valve  10  has particular utility in beverage or liquid dispensing machines, such as for example, coffee machines, soup machines, rug cleaning machines, ice making machines and the like. 
         [0021]    Valve  10  is generally comprised of a valve body  12 , a valve member  14 , a coil spring  16 , a snap plate  18 , a solenoid frame  20  and a solenoid  22 . 
         [0022]    Valve body  12  is preferably formed of a plastic or nylon material and includes a horizontally extending inlet  24  and a vertically extending outlet  26  disposed at generally 90 degrees with respect to inlet  24 . Valve body  12  also defines a valve chamber  28  which is located between inlet  24  and outlet  26 . As is well known, a circular valve seat (not shown) opens into the center of a valve chamber  28 . Liquid introduced through the inlet  24 , flows through the valve seat and exits through the outlet  26 . The outlet  26  is provided with a flow adjuster  30  for altering the flow rate of the outgoing liquid. The outlet  26  is further provided with a vent tube  32  that extends upwardly through a loop  34  on snap plate  18 . Valve body  12  includes a tube  36  on either side of the inlet  24  adapted to receive fasteners for mounting the valve  10  as desired. Extending radially outwardly from the valve chamber  28  is a circular crown  38  provided with attachment structure for permitting joinder of the remaining valve components to the valve body  12  as will be detailed below. 
         [0023]    The valve member  14  includes an elongated, cylindrical metallic plunger  40  having a lower end which is attached to a flexible diaphragm, and an upper end formed with a blind opening for supporting the lower end of spring  16 . The diaphragm is engagable with the valve seat to provide a seal. The plunger  40  and coil spring  16  extend upwardly through the snap plate  18  into the interior of solenoid  22 . The plunger  40  is designed to move up and down in response to energization and deenergization of solenoid  22 . 
         [0024]    Snap plate  18  is disposed on top of crown  38  and includes depending leg and pin structure received with a twisting frictional fit in the engagement structure of the crown  38  as set forth in the aforementioned U.S. Pat. No. 6,684,901. As best seen in FIGS.  5  and  8 - 10 , snap plate  18  has an upper surface  42  molded with a series of four spaced apart dog-legged cavities and a series of various relief cutouts  46 . The cavities  44  have walls  48  for enabling positioning of the frame  20  and the solenoid  22  over a limited range of rotary travel thereon. The upper surface  42  is also formed with an upstanding cylindrical neck  50  through which the plunger  40  extends. The neck  50  is provided with a number of outwardly projecting retaining elements  52  used for retaining the frame  20  in an operating position as shown in  FIG. 1 . The neck  50  is designed to be received in the bottom of a central passageway  54  formed completely through the solenoid  22 . 
         [0025]    Frame  20  is generally a C-shaped metal member, and includes a bottom end plate  56  and a top end plate  58  joined by a connector plate  60 . Bottom end plate  56  and top end plate  58  are formed with aligned with U-shaped slots  62  defined respectively by a pair of bifurcated bottom arms  64  and a pair of bifurcated top arms  66 . A lower surface of the bottom end plate  56  is provided with a depending nib  68  adjacent connector plate  60 . As will be understood, the nib  68  is engagable with any one of the walls  48  forming the cavities  44  in snap plate  18  as the frame  20  is rotated and slides thereon. 
         [0026]    Solenoid  22  has an encapsulated body  70  for protecting an internal coil (not shown) that surrounds passageway  54 . The body  70  has an upper end  72  formed with a ledge  74  provided with a pair of stop elements  76  that are engagable with top arms  66  of the frame  20 . Suitable terminals  78  for connection of electrical leads project outwardly from the upper end  72  of the solenoid  22 . The interior passageway  54  receives a tubular metal backstop member  80  having a spool-like backstop  82  pressed into the top end of a guide tube  84  that extends beyond a bottom end of the body  70 . The backstop  82  has a head  86  and a base  88  connected by a body  90  with a smaller diameter than the head and the body. A spring washer  92  encircles the guide tube  84  and is designed to sit between a countersunk surface  94  recessed in the upper end  72  of the solenoid  22  and the bottom of base  88 . The head  86  of the backstop  82  is formed with a small aperture  96  to release air from the passageway  54  during plunger movement. The aperture  96  also aids in preventing corrosion of the plunger  40 . The top end of the plunger  40  telescopes into a bottom end of the guide tube  84  with the spring  16  engaging the bottom of the backstop  82  so as to provide an upwardly biased force thereon. The body  70  is rotatably supported upon the neck  50  of the snap plate  18  but is normally limited in rotation in an operating mode as will be described below. 
         [0027]    As is well known, the force of coil spring  16  will normally urge valve member  14  to a closed position such that the diaphragm seals off the seat in the valve chamber  28  preventing flow from the inlet  24  to the outlet  26 . Energization of the solenoid  22 , however, will cause the plunger  40  and the diaphragm to be pulled upwardly to an open position so that flow between the inlet  24  and the outlet  26  may occur. With deenergization of the solenoid  22 , the coil spring  16  will again force the diaphragm into the closed position. 
         [0028]      FIGS. 1 and 7  show the valve  10  in a locked, operating position. Here, it is assumed that snap plate  18  has been connected to valve body  12  by a twisting snap fit as set forth in U.S. Pat. No. 6,684,901. It is also assumed that the valve  10  is typically mounted in a dispensing application such as, for example, in a beverage dispenser. With the solenoid  22  slidably mounted on the plunger  40 , the bottom arms  64  of frame  20  are frictionally engagable between the upper surface  42  of the snap plate  18  and the bottom of the retaining elements  52  on the neck  50 . The nib  68  on the bottom plate  56  is engaged against an end wall  48  of one of the cavities  44 . The top arms  66  of frame  20  are slidable between the head  86  and the base  88  of backstop  82  and forced against the base  88 . The ends of the top arms  66  are constantly engagable with the stop elements  76  on solenoid  22  to prevent relative rotation between the frame  20  and the solenoid  22 . The frame  20  thus frictionally holds the solenoid  22  in place on the valve body  12  during normal valve operation. 
         [0029]    The present invention provides a convenient, unique solenoid mounting arrangement which permits at least partial disassembly of the valve  10  and servicing of the solenoid  22  while the valve  10  is installed without the use of tools and fasteners. 
         [0030]    When it is desired to service the solenoid assembly, the snap plate  18  is held and the frame  20  and the solenoid  22  are rotated together to a servicing position shown in  FIGS. 2 and 6 . Nib  68  has been moved to a wall in a straight portion of cavity  44 . At this point, the backstop  82  is pressed downwardly against the biasing force of spring  16  and spring washers  92 . This releases the holding force on the frame  20  so that the nib  68  slides out of the cavity  44 , and the frame  20  is slidably removed from the snap plate  18  and the solenoid  22  as shown in  FIG. 3 . Now, full access to the solenoid  22  is permitted and the solenoid  22  with backstop  82  is lifted upwardly from plunger  40  for inspection and replacement as desired. 
         [0031]    Once replacement solenoid  22  is again slidably mounted on the plunger  40 , the frame  20  (shown in phantom lines) is reinstalled as depicted in  FIGS. 8-10 . Nib  68  is first aligned with the straight portion of the one cavity  44  with the bottom arms  64  sliding in frictional engagement between the snap plate  18  and the retaining elements  52 , and the top arms  66  sliding against the base  88  of backstop  82 . Bottom U-shaped slot  62  receives neck  50  on snap plate  18  and top U-shaped slot  62  receives body  90  on backstop  82 . Frame  20  is then pushed forwardly so that nib  68  engages a cavity wall  48  at  98  ( FIG. 9 ). Frame  20  is then rotated clockwise as shown by arrow A ( FIG. 10 ) so that the nib  68  engages wall  48  at  100  which redefines a locking position. It should be understood that the frame  20  and the solenoid  22  can be positioned as desired in any of the three other cavities  44  depending on the orientation of the solenoid terminals  78  relative to the installation environment. 
         [0032]    The valve  20  is thus more easily operated and serviced by making use of rotary and sliding motions of the frame  20  relative to the snap plate  18 , and a frictional fit of the frame  20  relative to snap plate  18  and the backstop  82 . 
         [0033]    While the invention has been described with reference to a preferred embodiment, those skilled in the art will appreciate that certain substitutions, alterations and omissions may be made without departing from the spirit thereof. Accordingly, the foregoing description is meant to be exemplary only and should not be deemed limitative on the scope of the invention set forth with the following claims.