Patent Publication Number: US-2004042337-A1

Title: Food processors

Description:
FIELD OF THE INVENTION  
       [0001] The present invention relates to food processors, in particular, although not exclusively, to blenders.  
       BACKGROUND OF THE INVENTION  
       [0002] It is well known that blenders comprise a jug for containing a processing blade, which jug attaches to a base motor unit for driving the processing blade. Generally, such blenders have a safety device such that the motor is only activated when the jug is locked onto the motor base.  
       [0003] it is common to find a blender jug having an integral handle formed from the same material as the jug, which material is usually glass.  
       [0004] Prior art blenders do not account for hazards associated with the rotating blade whilst the lid of the blender is removed. When the blade rotates, without the lid, material contained within the jug may be displaced from the jug.  
       [0005] A more serious hazard, associated with an open blender jug during operation of the blade, may be injury to the operator; for example, if the operator tries to push material into the jug, it is likely that injury to the operator&#39;s fingers and/or hands will be sustained.  
       [0006] Therefore, it is an object of preferred embodiments of the present invention to provide an improved blender.  
       SUMMARY OF THE INVENTION  
       [0007] Accordingly, the present invention provides a food processor comprising a processing container having an opening for placing food into the container and a processing mechanism operable to process food in the container; a lid engageable with the processing container to close the opening thereof; and a drive unit engageable with the processing container. The drive unit is operable to drive the processing mechanism only when both the lid and the drive unit are operably engaged with the processing container.  
       [0008] Optionally, the processing container comprises a jug. The jug may comprise a base unit, which base unit may be integral with or separate from the jug.  
       [0009] Optionally, the processing container comprises a handle. The handle suitably has an elongate conformation. Advantageously, the handle extends along the full height of the processing container.  
       [0010] Optionally, the handle comprises a first member and a second member. The first and second members may be complementary elongate portions joining together to form the handle.  
       [0011] The handle, and preferably the first member of the handle may comprise attachment means to allow the handle to be attached to the processing container. Any suitable fixing means may be used with the attachment means to attach the handle to the container. For example, the fixing means may comprise a mechanical fastener, such as a screw, rivet or similar. Alternatively, or in addition, the fixing means may comprise any suitable adhesive, cement or the like.  
       [0012] The first member may provide an inner surface of the handle. Preferably, at least part of a surface of the first member comprises an undulating profile providing a gripping section for a user.  
       [0013] Also, the second member may provide an outer surface of the handle.  
       [0014] The handle suitably comprises a passage extending therein, along at least a portion of the longitudinal extent thereof. The handle may be hollow along at least a portion thereof. Preferably, the handle is hollow along substantially the full, and more preferably the full, extent thereof.  
       [0015] Preferably, the food processor further comprises an actuator for signalling that the lid is operably engaged with the processing container.  
       [0016] The actuator may be movable between an open position, wherein the lid is not operably engaged with the processing container, and a closed position, wherein the lid is operably engaged with the processing container. Suitably, the actuator is biased into an open position.  
       [0017] Optionally, the actuator is an elongate member having a first and second end. Suitably, a pressure applied at the first end moves the actuator to the closed position.  
       [0018] Alternatively, or in addition, the actuator may comprise an electrical contact. Suitably, the electrical contact is in an open state when the lid is not operably engaged with the processing container and in a closed state when the lid is operably engaged with the processing container.  
       [0019] The actuator may be conductive. The actuator may comprise a conductive portion.  
       [0020] The actuator may be associated with the handle of the processing container. Suitably, the actuator extends along the full extent of the handle and at least part of the actuator may be contained within the handle. Suitably, the handle comprises a passage extending along the full extent thereof and the actuator extends along the full extent of the passage. Preferably, the handle is hollow along the full extent thereof and the actuator is contained within the handle and extends along the full extent thereof. The actuator may extend beyond one or both ends of the handle.  
       [0021] The lid may be operably engaged with the processing container when the lid is locked in a closed position on the processing container.  
       [0022] Optionally, the food processor comprises an alignment mechanism for positioning the processing container relative to the drive unit. Any suitable alignment mechanism may be used.  
       [0023] The alignment mechanism may comprise an opening in the drive unit for receiving an element of the processing container, or vice versa. Suitably, the alignment mechanism comprises an opening in the drive unit for receiving the actuator.  
       [0024] The drive unit may also comprise a controller, which controller comprises a switch assembly.  
       [0025] The switch assembly suitably comprises first and second contacts, which are biased into an open position. Suitably, at least one of, and preferably both of, the first and second contacts are spring mounted. One or both of the first and second contacts may be mounted on a contact holder.  
       [0026] Movement of the actuator may cause movement of the first and/or second contacts. Suitably, the actuator contacts the first and/or second contact in order to move the first and second contacts from the open position to the closed position. Preferably, the actuator contacts the contact holder of the first and/or second contact in order to move the first and second contacts from the open position to the closed position.  
       [0027] Optionally, the switch assembly cooperates with the actuator and the alignment mechanism such that when the processing container is correctly positioned on the drive unit and the lid is operably engaged with the processing container, the switch assembly allows activation of the control means.  
       [0028] Suitably, movement of the actuator indicates to the switch assembly that the lid is operably engaged with the processing container.  
       [0029] The lid may be configured to cooperate with the actuator so as to effect movement of the actuator. Suitably, the lid comprises a protrusion, which interacts with the actuator when the lid is operably engaged with the processing container to effect movement of the actuator.  
       [0030] The processing mechanism is part of the base unit. Suitably, the processing mechanism is detachable from the base unit; therefore facilitating easier cleaning.  
       [0031] The lid may comprise an opening and a removable plug. The opening advantageously provides a filling port for safe addition of material to the processing container whilst the food processor is in use.  
       [0032] Other objects, features and advantages of the present invention will become apparent from the following detailed description, the accompanying drawings, and the appended claims. 
     
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
     [0033] An embodiment of the invention will now be described, by way of example only, with reference to the accompanying schematic drawings, in which:  
     [0034]FIG. 1 is a partially exploded view of a blender type food processor;  
     [0035]FIG. 2 shows the blender of FIG. 1 when assembled for use;  
     [0036]FIG. 3 shows an exploded view of a processing container for the blender of FIGS. 1 and 2;  
     [0037]FIG. 4 shows an exploded view of the drive unit of the blender of FIGS. 1 and 2;  
     [0038]FIG. 5 a  shows the switch assembly of FIG. 4 as assembled and viewed from the direction indicated by arrow A;  
     [0039]FIG. 5 b  shows the switch assembly of FIG. 4 as assembled and viewed from the direction indicated by arrow B;  
     [0040]FIG. 6 a  shows the switch assembly of FIGS. 5 a  and  5   b  in an open position;  
     [0041]FIG. 6 b  shows the switch assembly of FIG. 6 b  in a closed position; and  
     [0042]FIG. 7 shows a sectional view of the blender as previously shown in FIG. 2. 
    
    
     [0043] Throughout the Figures like reference numerals are used to refer to like features.  
     DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENT  
     [0044] The blender  1 , of FIGS.  1  to  6 , comprises three main parts, a drive unit  2 , a processing container  3  having an opening for enabling food to be placed in the container  3 , and a lid  4  for closing the opening.  
     [0045] The processing container  3  comprises a handle assembly  7  and a jug  9 . The jug  9  has a base unit  13 . A processing mechanism having at least one processing blade  20  is located in the base unit  13 . The processing mechanism may have any number of blades  20  and may have any suitable construction for processing food. In the context of the invention, the term food is intended to be read broadly and processing food may include processing solid foods, such as grinding vegetables, or liquid foods, such as blending milkshakes. Blades need not be used, and grinding elements or the like may be substituted therefor.  
     [0046] The handle assembly  7  (shown exploded in FIG. 3) extends the full height of the jug  9 , and includes two elongate members  8 ,  10 . An inner member  8  of the handle assembly has an undulating profile to provide a comfortable grip for the operator. The inner member  8  also provides attachment means for connecting the handle assembly  7  to the jug  9 . In the embodiment shown, the inner member  8  is connected to the jug  9  by screws, but any other mechanical fastener, adhesive or a combination thereof may be used.  
     [0047] An outer member  10  of the handle assembly  7  provides the outer casing for the handle assembly  7 . The inner  8  and outer  10  members form two halves of the handle assembly  7 , which when joined together provide a hollow handle  7 .  
     [0048] An actuator  11  has a shape that corresponds substantially with the profile of the handle assembly  7 . The actuator  11  extends through the hollow handle assembly  7 . A spring  12  is seated between the upper end of the actuator  11  and the interior upper surface of the inner member  8 . The spring  12  biases the upper end of the actuator  11  towards the outer member  10 .  
     [0049] A slot  6  is provided at the top of the handle assembly  7 , between the inner  8  and outer  10  members, providing access to the upper end of the actuator  11 .  
     [0050] The lid  4  has a protruding lug  5  that fits into slot  6  when the lid  4  is fitted to the jug  9 . The lid  4  also has an opening and a removable plug  14  to allow material to be added to the jug  9  whilst the blender  1  operates.  
     [0051] It should be understood that the container  3  can have any construction or configuration and the invention is not limited to the one illustrated.  
     [0052] A drive means  24 , such as an electric motor, is housed in the drive unit  2  provides driving power to the processing blade  20  via a cog  21 . The drive unit  2  comprises a controller, illustrated by way of example as a safety switch assembly  15  that will prevent activation of the drive means  24  unless electrical contact is made between contacts  16 ,  17  of the switch assembly  15 .  
     [0053] The switch assembly is shown in exploded view in FIG. 4 and assembled in FIGS. 51, 5 b,    6   a  and  6   b.    
     [0054] The switch assembly  15  comprises a first contact holder  30 , which has a dog-legged configuration. The switch assembly further comprises a second contact holder  36 . The first contact  16  is mounted in the contact support  32  and the second contact  17  is mounted in the second contact holder  36 . In this embodiment, the first contact  16  and the second contact  17  are connected to the respective contact holder  30 ,  36  by means of a silver faced bimetallic rivet.  
     [0055] The first and second contacts  16 ,  17  are mounted within a housing  34 . The first contact holder  30  is spring mounted within the housing  34  by means of a spring  38 . The second contact holder  36  is spring mounted within the housing  34  by means of springs  42 .  
     [0056] As can be seen from FIGS. 6 a  and  6   b,  when the switch assembly  15  is open, the contacts  16 , and  17  are maintained separated from one another by means of the spring  38 . When a downwards force is applied to the first contact holder  30  by means of the actuator  11 , the spring force  38  is overcome and the contacts  16 ,  17  are brought together to move the switch assembly to the closed position.  
     [0057] In the closed position, the electric circuit to the drive unit  2  can be completed to allow activation of the drive means  24 .  
     [0058] The drive unit  2  further comprises an alignment mechanism, illustrated by way of example as an alignment opening  26 . The alignment opening  26  is located to be aligned with the lower end  22  of the actuator  11  when the jug  9  is correctly positioned on the drive unit  2 . Any suitable mechanism for facilitating alignment may be used.  
     [0059] It should be understood that the drive unit  2  may have any construction or configuration and the present invention is not limited to the one illustrated.  
     [0060] Safe operation of the blender  1  depends on both, the lid  4  being fitted to the jug  9 , and the processing container  3  being correctly aligned on the drive unit  2 .  
     [0061] The processing container  3  attaches to the drive unit  2 , via the base unit  13 , by twisting into a locking position, in which it is correctly aligned. The locked and unlocked positions are indicated visually by alignment of arrows on the casing of the drive unit  2  and the casing of the base unit  13  (see FIG. 1).  
     [0062] When the base unit  13  is locked onto the drive unit  2 , the lower end  22  of the actuator  11  is axially aligned with the safety switch assembly  15 . When the lid  4  is fitted on the jug  9  the protruding lug  5  enters the slot  6  (see FIG. 1). The lug  5  connects with the upper end of the actuator  11  and pushes it downward against the restraint of spring  12 . As the actuator  11  moves downwards its lower end  22  passes through the alignment opening  26  and makes contact with the first contact holder  30  of the safety switch assembly  15  which effects contact of the first and second contacts  16 , 17  allowing current flow through the safety switch assembly  15  allowing safe operation of the blender  1  via the control unit.  
     [0063] Conversely, removal of the lid  4  causes expansion of the spring  12 , thereby raising the actuator  11  to break the contact between the lower end  22  of the actuator  11  and the first contact holder  30 . The force of spring  38 , will then cause the first and second contact  16 ,  17  to separate, thus preventing operation of the drive means  24 .  
     [0064] Only when both the first  16  and second  17  contacts are closed can current flow through the switch assembly  15  to activate the processing blade  20 .  
     [0065] The foregoing description has been provided solely to illustrate the structural and functional principles of the present invention and is not intended to be limiting. To the contrary, the present invention is intended to encompass all substitutions, modifications, alterations and equivalents within the spirit and scope of the appended claims.