Patent Publication Number: US-2006009089-A1

Title: Safety electrical connection assembly for appliances

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
      This application claims priority to U.S. Provisional Patent Application Ser. No. 60/586,961 filed on Jul. 9, 2004, incorporated herein by reference in its entirety. 
    
    
     BACKGROUND OF THE INVENTION  
      1. Field of the Invention  
      The present invention relates to electrical connection assemblies and, more particularly, to electrical connection assemblies that enable selective contact between terminal ends and appliance conductors while preventing inadvertent contact with terminal ends when not in use.  
      2. Description of Related Art  
      Various electrical appliances exist in which it is desirable to allow one or more parts to be removed from a base, in which the base conducts electrical energy from an external power source and transfers the energy to the removable part. For example, certain cooking appliances have an electrical base with a removable pot or griddle, wherein the pot or griddle has conductive pins that, when in conductive contact with the base, provide electrical energy to on-board heat elements.  
      Known devices achieve this result by providing a movable cover on the base, whereby the cover selectively slides over the terminal ends on the base to protect them while the removable part is disengaged. When the removable part is engaged, one or more mechanisms cause the cover to be slid away from the terminal ends to expose them and allow them to contact the appliance conductor pins.  
     OBJECT AND SUMMARY OF THE INVENTION  
      It is an object of the present invention to overcome the shortcomings of the prior art mentioned above. These and other objects are achieved by the present invention described herein.  
      It is desirable to provide an electrical connection assembly that enables selective contact between terminal ends and appliance conductors while preventing inadvertent contact with terminal ends when not in use, wherein the need for complex or moveable parts is eliminated. The elimination of such parts eliminates potential wear, costs, and complexity in assembly. Furthermore, safety is enhanced because potential of failure is eliminated.  
      The present invention achieves these and other objectives by provided terminal ends that are sunk into openings in a base such that they cannot be contacted by any person or object larger than the openings into which they are sunk. In order to provide positive contact and resistance to pull-out, a novel spring leaf design is employed. The appliance conductor pins are shaped and sized to enter the openings into which the terminal ends are sunk, and to simultaneously block access to the openings by any other objects. The pins enter into and are held by the leaf springs, which surround the pin in a flower-petal configuration. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
      The present invention is more fully understood by reference to the following detailed description of an illustrative embodiment with the drawings identified below.  
       FIG. 1  is a top view of a connector block according to the present invention.  
       FIG. 2  is a side, sectional view of the connector assembly according to the present invention.  
       FIG. 3  is a side, sectional view of the connector assembly according to the present invention. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION  
      Referring to  FIGS. 1 and 2 , an electrical appliance contains a connector block  10 , which can be permanently attached to the base of the electrical appliance. The connector block  10  comprises a body  12  adapted to be attached to an electrical appliance base  13 . The block  10  includes openings  14 ,  16 ,  18 . Opening  16  is adapted to receive a grounding pin  24 , which can be attached to a removable portion  20  of an electrical appliance. Openings  14 ,  18  receive two live conductor pins  22  of a removable portion  20  of an electrical appliance. The conductor pins  22  can be of various types, such as calrod pins. The openings  14 ,  18  for the conductor pins are identical and, thus, only one is illustrated in  FIGS. 2-3 , and only one is discussed below.  
       FIG. 2  shows the electrical connection assembly in its “disassembled” state.  FIG. 3  illustrates the assembly in its “assembled” state. The opening  14  in the connector block  10  contains a live electrical terminal end. This live electrical terminal end can be in the configuration of four spring-biased contacts  26 . In a preferred embodiment, these spring-biased contacts are leaf springs, in a “cauliflower” type arrangement. This leaf spring design provides positive contact and resistance to pull-out.  
      Each leaf spring  26  has a distal tip  28  and a curved mid-portion  30 . The distal tips  28  are distanced from the edge of the opening  14  at a sufficient distance from the top surface  32  of the block  10  to prevent inadvertent contact with the leaf springs  26 . The diameter of the block opening  14  would preferably be small enough to prevent an operator&#39;s fingers from entering the opening  14 .  
      When the removable part is positioned over the base  13  for operation, the conductor pins  22  enter the opening  14  and the pin ends  34  are received between the springs  26 , which flex and make contact along the curved mid-portions  30 , as shown in  FIG. 3 . The four leaf-shaped connectors, which are biased inward, ensure a tight fit between the conductor pins  22  and the live terminals  26 . The grounding pin  24  enters the block opening  16 .  
      In order to further prevent an operator&#39;s fingers or other objects from entering the live electrical terminal end opening  14 , a collar  36  is utilized. The collar  36  is positioned on the conductor pins to fill the openings  14  when the pin ends  34  are engaged with the springs  26 . The collar  36  is located at a distance from the pin end  34  and preferably has a diameter slightly smaller than that of the opening  14 . This slightly smaller diameter will prevent objects from entering the opening  14 .  
      The present invention assembly is suitable for use with a variety of appliances including, but not limited to, fryers, fry pans, kettles and griddles for consumer use.  
      While a preferred embodiment of the invention has been herein disclosed and described, it is understood that various modifications can be made without departing from the scope of the invention.