Abstract:
An appliance comprises a housing containing an electric motor whereof the output shaft is designed for driving a working tool, a switch controlling the motor speed which is actuated by a hand-operated control knob mounted rotating about an axis of rotation to take up an “off” position and several “on” positions, and a device for ejecting the tool capable of being controlled by the knob in its “off” position. The button is also mounted tilting about an axis transverse to its axis of rotation so as to control the actuating of the tool ejecting device. The appliance is particularly applicable to hand-operated electric food mixers.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This is the 35 USC 371 national stage of International application PCT/FR99/00140, filed on Jan. 22, 1999, which designated the United States of America. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to an electric hand-held kitchen appliance, adapted to drive at least one working tool, comprising a housing enclosing an electric motor whose output shaft is adapted to drive the working tool having an axle of which one end is inserted in an opening provided in the housing, a speed control switch for the motor which is actuated by a manually operable button rotatably mounted along an axis of rotation so as to be able to occupy a “stop” position or several angularly offset “operating” positions, and a device for ejecting the working tool which is controllable by the button in the “stop” position. 
     It is particularly applicable, but not exclusively, to an electric hand-held beater adapted to drive at least one whisk or at least one kneader. 
     BACKGROUND OF THE INVENTION 
     In known electric kitchen appliances of this type, such as a hand-held beater, the manually actuated rotatable button is adapted, in addition to control the switch to regulate the speed of the motor, to control the ejector device for the whisks by means of a control mechanism, of the lever and cam type, and, to this end, is turned by the user beyond its “stop” position to control the actuation of the ejection device by the whisks. However, the ejection of the whisks being carried out in the same direction of movement of rotation of the button which permits control of the speed of the motor, it can be involuntarily used by the user when the latter turns the button in an untimely manner. Moreover, the manually operated rotatable button has a high angular swing to carry out both the control of speed of the motor and the control of ejection of the whisks, and as a result occupies a relatively large volume in the apparatus. 
     SUMMARY OF THE INVENTION 
     The invention has particularly for its object to overcome these drawbacks and to provide a hand-held electric kitchen appliance, of the type described above, in which the ejection of the working tool can be carried out easily and with precision in even the same stopped position of the manually-operated button. 
     According to the invention, the manually operated button is also swingably mounted about an axis transverse to its axis of rotation so as to control the actuation of the working tool ejector device. 
     Thus, the fact that the ejection of the working tool is carried out by a swinging movement of the button which is thus different from the rotation button of the latter, permits control of the speed of the motor, and requires on the part of the user a voluntary action on the button, which action is moreover particularly easy. Moreover, because of its double rotative and swinging movement, the manipulating button operates a reduced space in the apparatus. 
     According to another important characteristic of the invention, the manually operable button comprises a lug which directly actuates the ejector device for the working tool during swinging of the button. This direct actuation lug therefore constitutes a simple mechanical means, contrary to the complicated cam and lever mechanism according to the prior art, thus leading to less costly production of the manually operable button. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The characteristics and advantages of the invention will become clearer from the description which follows, by way of non-limiting example, with reference to the accompanying drawings, in which: 
     FIG. 1 is a view partially in vertical cross-section of an electric hand-held kitchen appliance such as a beater-mixer, according to the invention; 
     FIG. 2 is a top plan view of the apparatus of FIG. 1; 
     FIG. 3 is a view on an enlarged scale and in perspective, of a manually operated button associated with a switch, this button being shown in one position for control of the speed of the motor (in full lines) and in a position to eject a working tool (in broken lines); 
     FIG. 4 is an exploded schematic perspective view of the switch of FIG. 3; 
     FIG. 5 is a view on an enlarged scale and in perspective, of the button associated with the switch, showing the actuation of a finger by a cam of the button when the latter occupies a position for controlling the speed of the motor; and 
     FIGS. 6 and 7 are schematic views showing a conductive track and a movable contact respectively, not urged by the finger of the switch of FIG. 5 (FIG. 6) and urged by this same finger (FIG.  7 ). 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     In the embodiment shown in FIG. 1, the electric hand-held kitchen appliance  1  is an electric hand-held beater-mixer adapted to drive selectively at least one beating tool, such as a whisk or a kneader, or a mixing tool turning at high speed, such as for example a rotatable helical mixer. 
     The hand-held beater-mixer  1  shown in FIG. 1 comprises a housing  2  of generally prismatic shape having a recessed portion  4  which delimits a handle  5 , and enclosing an electric drive motor  7  provided with an output shaft  8  with an axis XX′ and disposed in the lower portion  10  of the housing  2  extending horizontally therein. 
     The shaft  8  of the drive motor  7  carries at its forward end  12  an endless screw (not shown) which coacts with two helicoidal pinions each turning about a vertical axis YY′ perpendicular to the axis XX′, and which form with the latter a reducer  14 . These two helicoidal pinions are located in the forward portion  16  of the housing and are connected respectively to two coupling devices  18  along the axis YY′, of which only one is visible in FIG. 1, adapted respectively to receive, by insertion through two openings  20  provided in the base  22  of the housing  2 , the two upper ends of the respective axles  24  of two beating tools, in this case two whisks  26  of which only one is shown in FIG. 1; these two whisks  26  can be fixed in the coupling devices  18  either side by side or one behind the other. 
     In a manner known per se, the rear end  28  of the shaft  8  of the drive motor  7  carries a rotatable drive  30  adapted to receive, by insertion through an opening  32  provided in the rear wall  33  of the housing  2 , a mixing tool (not shown), such as for example a mixing foot. 
     As shown in FIG. 1, in the upper portion  35  of the housing  2 , in the front part of the latter, is arranged a projecting manually operable button  37  which is rotatably mounted about an axis of rotation designated ZZ′, transverse to the axis YY′ of the whisks  26 . This manual manipulating button  37  is adapted to actuate an electric switch  40  which places the motor  7  out of service and regulates its speed of rotation. Thus, the button  37  can occupy a “stop” position and one or several successive “operating” positions, for example three in number, disposed at a certain angle relative to each other, on the same side of the “stop” position, so as to constitute a control sector for the speed of motor  7 , permitting, in this case, selecting three speed levels for the motor. These three positions of the electric switching of the switch  40  are indicated in the form of suitable marks on the upper wall  42  of the housing  2 , in front of the button  37  for actuating the switch. 
     As regards FIG. 1, the beater-mixer comprises moreover an ejector device  45  for the whisks  26  which is controlled by the manually operated button  37  in its “stop” position. In this embodiment, the ejector device  45  is constituted by a movable ejection member  47  arranged vertically in the front portion  16  of the housing  2 , between the button  37  and the two coupling devices  18 . This ejection member  47  has a lower portion  47   a  which bears on the upper ends of the axles  24  of the two whisks  26 , and is resiliently urged by a return spring (not shown) to pass from a low position in the absence of the whisks to a high position (FIG. 1) during mounting of the whisks, and inversely from this high position to the low position in which the ejection member  47  frees the whisks under the action of the manually operated button  37  in its “stop” position. 
     According to the invention, as shown in FIG. 3, the manually operated button  37  is also swingably mounted about an axis, designated BB′ in FIG. 3, transverse to its rotation axis ZZ′ so as to control the actuation of the ejection member  47  for the whisks  26 . 
     In the embodiment shown in FIG. 4, switch  40 , which will be described in detail hereafter, is of the rotatable type and is comprised by two external concentric disks secured against each other by any suitable coupling means, namely a fixed disk forming a support  49  provided axially of a shaft  51  mounted fixedly in the housing and constituting the rotation axis ZZ′ of the button  37  (FIGS.  1  and  3 ), and a rotatable disk  53  forming the support for the switch made of insulating material and adapted to be driven in rotation by the manually operated button  37  when the latter is turned about its axis ZZ′ to occupy its “stop” position or one of its “operating” positions. 
     In this example, as will be seen in FIGS. 1 and 3, the manually operated button  37  is shaped like a spherical cap  54  which is surmounted by a handle  55  of substantially cylindrical shape with an axis UU′ (FIG.  3 ), and which is swingably mounted on its base on two pins  57 , of which only one is visible in FIGS. 3 and 4, formed on the external periphery of the rotatable disk  53  of switch  40  and diametrically opposed to each other so as to constitute the swinging axis BB′ (FIG. 3) of the spherical cap  54 . 
     Preferably, the spherical cap  54  and the handle  55  of the manually operated button  37  are molded of a single piece of plastic material. 
     In this embodiment, the axis of rotation ZZ′ and the swinging axis BB′ of the spherical cap  54  of the button  37  are located in planes that are orthogonal to each other (FIG.  3 ). 
     As shown in FIGS. 1 and 2, the handle  55  of the manual operating button  37  projects from the upper wall  42  of the housing  2  through a cutout  60  provided in the housing, whilst the spherical cap  54  is mounted below this cutout  60  and is applied, with slight clearance play, against the internal surface of the upper wall  42  of the housing bordering the cutout  60 , thereby forming a sealing joint. 
     The cutout  60 , FIG. 2, comprises a first track  60   a  of arcuate form along which the spherical cap  54  of the button  37  can move, during rotation about its axis ZZ′, to occupy successively its different “operating” positions, three in number in the selected example, corresponding respectively to the three predetermined levels of speed of the motor, as well as its “stop” position, and a second track  60   b  communicating with the first track  60   a  and extending beyond the latter and located at the level of the “stop” position of the button  37 , so as to permit swinging about a wide angular path, of the cap  54  of the button  37 , about its axis BB′ (FIG.  3 ), when the button occupies its “stop” position in which it controls the actuation of the ejection member  47  for the whisk. 
     In a preferred embodiment, the cap  54  of the manually operated button  37  comprises at its base a lug  62  (FIGS.  1  and  3 ), preferably molded with the cap  54 , which actuates directly the ejection member  47  for the whisks when the spherical cap  54  of the button  37  in the “stop” position is swung forwardly about its axis BB′ (as shown in broken lines in FIG.  3 ), with the help of the handle  55  which is moved into the cutout  60  (FIG. 2) coming into abutment, at the end of swinging of the cap  54 , against the forward edge of the track  60   b  of the cutout  60 , this latter thereby serving as a limit to swinging movement. Under the direct action of the lug  62 , the ejection member  47  passes from its high position to its low position in which it frees, by its lower portion  47   a  (FIG.  1 ), the whisks  26 ; after ejection of the whisks, the ejection member  47  is returned by its spring to its upper position. 
     Thus, thanks to this swinging movement of the cap  54  of the manually operated button  37 , separate from the rotative movement of this latter to control the different speeds of the motor, the ejection of the whisks desirably requires on the part of the user a deliberate action, easily carried out, on the button  37 , and this in the same stopped position of the button. Moreover, the lug  62  for directly actuating the ejection member  47  of the whisks constitutes a particularly simple and inexpensive member. 
     As to FIG. 4, the fixed disc  49  of the rotatable switch  40  comprises several fixed contacts formed by conductive areas distributed in the same arc of a circle, namely a so-called common track  64  and three tracks  65 ,  66  and  67  corresponding respectively, in the selected example, to the three predetermined speeds of the motor  7 , as well as an internal conductive track  68 , concentric to the preceding and corresponding to a high speed, so-called instantaneous operation, which is used for example for a mixing foot. The various tracks  64 - 68  are all electrically connected, in a manner known per se, to a printed circuit  70  (FIG. 1) which, in the example illustrated in FIG. 1, is mounted vertically in the housing  2 . The disc  49 , FIG. 4, is made of an insulating material in which are preferably overmolded the conductive tracks  64 - 68 , and comprises at its lower portion a substantially parallelepipedal insulating bar  72 , for example molded with the disc  49 , extending into the housing  2  transversely to the shaft  51  and comprising on its forward face an angular sector with several indexing notches  74  corresponding respectively to the “stop” position and to the different “operating” positions of the manually operated button. 
     On the rotatable disc  35  of the switch  40 , FIG. 4, is fixedly mounted, by any suitable securement means, a cursor  76  with flexible metallic blades  77  carrying at the end two movable contacts  78 ,  79  which are adapted respectively to coact with the common track  64  and with one of the three tracks  65 ,  66 ,  67  according to the “operating” position of the button  37 . For purposes of clarity, there has not been shown the movable contact blade adapted to coact with the track  68  corresponding to the instantaneous speed of operation for a mixer foot. The contacts  78  and  79  extend in a same vertical plane designated P in FIG.  4 . The disc  53  comprises in its lower portion a rounded tongue  81  having a vertically descending tooth  83  engaged successively, according to the rotation of the disc  53 , in the different indexing notches  74  of the bar  72  according to the “stop” and “operating” positions of the manually operated button  37 , see FIG.  3 . 
     According to another aspect of the invention, the cap  54  of the manually operated button  37  is moreover adapted to swing about its axis BB′ in each of the “operating” positions of the button, according to an angular path substantially less than that permitting controlling the ejection of the whisks, with the aid of the handle  55  which is moved into the cutout  60  (FIG. 2) coming into abutment, at the end of swinging of the cap  54 , against the forward edge of the track  60   a  of the cutout  60 , this latter serving to limit swinging. As shown in FIGS. 1 and 5, the cap  54  of the button  37  comprises internally a cam  85  that actuates, upon swinging of the cap  54  in each of the “operating” positions of the button, a finger  87  which is movably mounted in the rotatable disc  53  of the switch  40  (FIG. 5) and which actuates a flexible supplemental metallic blade  89  with a movable contact  90  (FIG. 4) located behind the plane P and coacting with a specific conductive track, designated  92  in FIG. 4, carried by the fixed disc  49  of the switch  40 , so as to increase the speed of the motor during a short period, thereby facilitating, for example, incorporation of ingredients in the course of preparation of foodstuffs. 
     In FIG. 6, there is shown schematically the finger  87  in a rest position, defined before swinging of the cap  54  of the buttons  37  in each of its “operating” positions, and in which it bears on the metallic blade  89  carrying at its end the movable contact  90  located at a distance from the associated conductive track  92 ; in FIG. 7, there is shown this same finger  87  in a working position in which it is actuated by the cam  85  of the cap  54  of the button during swinging of this cap in each of its “operating” positions of the button, and in which it bends the metallic blade  89  so as to apply the movable contact  90  against the conductive track  92 , thereby permitting increasing the speed of the motor. 
     It will be noted that the invention described above in the context of an electric hand-held beater-mixer is applicable also to any other type of hand-held electric kitchen appliance using ejection of the working tool and a variation of the speed of the motor, such as for example an electric knife or else an immersed mixer.