Patent Publication Number: US-2012043406-A1

Title: Drive device for driving a work unit

Description:
The invention relates to a drive device for driving a work unit and a method for driving a work unit. 
     Drive devices are known in manifold different types of embodiments and are used in manifold technical fields. Thus, using drive devices for driving grinding elements for foods in grinding devices and stirring elements for sauces in stirring devices is already known, for example. 
     A grinding device for food is known from WO2007/009654, in which a spindle is used as a drive device for driving grinding elements. A coupling device, which is connected to the grinding elements, is fixedly connected to the spindle in this grinding device. The spindle is partially housed and the grinding elements are completely housed inside a housing of the grinding device. 
     Such a connection of the drive device to the coupling device of the grinding elements has manifold disadvantages. Thus, because of the fixed connection of the coupling device to the drive device, it is not possible to use the drive device for other devices, such as stirring devices. I.e., every device must be provided with a separate drive device, which in turn increases the production costs of the respective device. A further disadvantage of such a connection is that the devices are relatively large, whereby the storage space required for the individual device is increased. 
     It is the object of the present invention to provide a drive device which can be used in a plurality of devices. A further object of the invention comprises ensuring that the size of the respective device is reduced. 
     These objects are achieved according to the invention by the features of Patent claim  1  or Patent claim  13 , respectively. Advantageous embodiments of the invention are characterized in the subclaims. 
     The invention has the advantage that a coupling device of the work unit can be engaged with a rotation transmission unit of the drive device. It is thus possible for the drive device and the work unit to be implemented modularly as separate components. This allows the drive device to be able to be used to drive multiple different devices, each having different work units. A further advantage of such a modular implementation is that the size of the individual device decreases, since the devices no longer necessarily must have a drive unit. As a result, the total required storage space of the devices is also decreased, since these have a small size and the drive unit can be stored separately from the respective device. In addition, an advantage of the invention is that the production costs of the individual devices are decreased, since the devices can be produced without a drive device, for example. 
     In a further advantageous embodiment of the invention, by providing a partition unit between the drive device and the work unit, soiling of the drive device can be prevented. Therefore, only the work unit must still be cleaned after operation of the device. 
     Furthermore, in a further advantageous embodiment of the invention, using the coupling element of the drive device, the drive device can be fixed in a partition unit. The coupling element is implemented so that it can be inserted into a corresponding recess of the partition unit. A further advantage is that through the removable fastening of the coupling element on the drive device, a correspondingly shaped coupling element can be attached to the drive device depending on the shape of the recess of the partition unit. Therefore, the usage capability of the drive device is increased, since it can be inserted into differently shaped recesses using the partition element. 
    
    
     
       Details of the invention are explained in greater detail on the basis of the drawing, identically acting elements being provided with the same reference numerals. In the figures: 
         FIG. 1 : shows an exploded view of a grinding device, 
         FIG. 2 : shows a sectional view of a drive device, 
         FIG. 3 : shows the grinding device in a partially assembled state, 
         FIG. 4 : shows the grinding device in the assembled state. 
     
    
    
     The grinding device  1 , which is shown in an exploded view in  FIG. 1 , has a drive device  10 , a partition unit  20 , and a container  40 . The drive device  10  has a rotationally-fixed actuating device  11 , a coupling element  14 , and a housing  13 , which is situated between the actuating device  11  and the coupling element  14 . 
     The actuating device  11  has a plunger shape and is displaceable along a longitudinal axis of the drive device  10 . During a movement of the actuating device  11 , it moves relative to the housing  13 , which is not movable in the longitudinal direction. The coupling element  14  is removably connected to the housing  13 . 
     The partition unit  20  has a partition element  21 , which terminates the container  40 . The partition element  21  has a recess  22 , which has the same shape as the coupling element  14  of the drive device  10 . The recess  22  has an opening  23 , which is dimensioned in such a way that a coupling device  31  of a drive unit  30  can go through it. 
     In addition to the coupling device  31 , the work unit  30  has a work element  32 , which is connected to the coupling device  31 . The coupling device  31  is implemented in this embodiment as a body having a polygonal shape, but can also have other shapes, The work element  32  is implemented in this case as a cylindrical body, on which grinding elements, which run transversely to its axis, are situated for grinding foods. The work elements  32  can be implemented as stirring elements, spinning elements, striking elements, and/or as other tool elements instead of the grinding elements, depending on the device. The work unit  30  has an opening for placing the work unit  30  on a mounting element  41  on the end remote from the coupling device  31 . The mounting element  41  is connected to the container  40  and is used to fix the work unit  30 . The container  40  is used to accommodate the foods, sauces, etc. to be processed and is implemented as cylindrical, other shapes also being conceivable. 
       FIG. 2  shows a sectional view of the drive device  10 , in which the actuating device  11  is located in a maximally extended position. The drive device  10  is a spindle drive device  10  in this case. However, other drive devices are also conceivable, which have another drive unit  16  instead of a spindle  16 . It is recognizable from  FIG. 2  that the actuating device  11 , the housing  13 , and the coupling element  14  each form a cavity. The rotationally-fixed actuating device  11  is coupled to a rotationally-fixed rotation generation unit  15 , which is implemented as a spindle nut  15  and is designated in such a way hereafter. The spindle nut  15  can be coupled to the spindle  16 . More precisely, the spindle nut  15  can be coupled to a thread of the spindle  16 . In this case, any possible embodiment which allows a conversion of a longitudinal movement into a rotational movement of the spindle  16  is understood as a thread. I.e., the thread is not to be limited to a screw thread, for example. 
     Inside the cavity of the housing  13 , the spindle drive device  10  has a spring  17 , which is connected at one end to the spindle nut  15 . At the end remote from the spindle nut  15 , the spring  17  is situated inside the spindle drive device  10  in such a way that it can be pre-tensioned in the direction toward the coupling element  14  during a movement of the spindle nut  15 . In addition, the spindle drive device  10  has a locking device (not shown in  FIG. 2 ). Using this locking device, during an actuation of the grinding device  1 , the actuating device  11  can be locked in the actuated, compressed position and a movement of the actuating device  11  into the starting position can thus be prevented. 
     The spindle  16  extends over the respective cavities of the actuating device  11 , the housing  13 , and the coupling element  14 . The spindle  16  is coupled on its end remote from the actuating device  11  to a rotation transmission unit  18 . The rotation transmission unit  18  has a coupling opening  19  corresponding to the polygonal shape of the coupling device  31 . Through such a shape of the coupling opening  19  of the rotation transmission unit  18 , it is ensured that the rotational movement of the spindle  16  is transmitted via the rotation transmission unit  18  and the coupling device  31  to the work elements  32  when the coupling device  31  is engaged with the rotation transmission unit  18 . Alternatively, the rotation transmission unit  18  can be situated in the partition unit  20 . In this case, the rotation transmission unit  18  would be connected or coupled to the work unit  30  and would have a coupling for coupling to the spindle  16  on the end facing toward the spindle  16 . The spindle  16  can have multiple sections each having different thread pitches. The number and implementation of the sections is a function of the requirements with respect to the torques to be delivered by the spindle  16  and/or with respect to the required speeds of the spindle. 
       FIG. 3  shows the grinding device  1  in a partially assembled state, the coupling element  14  of the drive device  10  not yet having been inserted into the recess of the partition element  21 . The partition element  21 , which is implemented as a lid, for example, is placed on the container  40 , so that it terminates it. A part of the coupling device  31  protrudes out of the opening  23  of the recess  22 . 
       FIG. 4  shows the grinding device  1  in the assembled state. The coupling element  14  of the spindle drive device  10  is inserted into the recess  22  of the partition unit  20 . The part of the coupling device  31  protruding out of the recess  22  is engaged with the coupling opening  19  of the rotation transmission unit  18 . More precisely, the part of the coupling device  31  protruding out of the recess  22  is inserted into the coupling opening  19  of the rotation transmission unit  18 . 
     The assembly of the grinding device  1  is described hereafter. The work unit  30  is placed in a first step on to the mounting element  41  of the container  40 , in order to fix the work unit  30  inside the container  40 . Subsequently, the partition unit  20  is placed on the container  40  to terminate it. Alternatively, the partition unit  20  can be fixedly connected to the work unit  30 , so that the container  40  is already terminated when the work unit  30  is placed on the mounting element  41 . Furthermore, it is checked in a further step whether the shape of the coupling element  14  corresponds to the shape of the recess  22  of the partition element  21 . If this is not the case, a corresponding coupling element  14  is removably connected to the housing  13  of the spindle drive device  10 . Finally, the coupling element  14  of the spindle drive device  10  is placed in the recess  22 , the part of the coupling device  31  protruding out of the opening  23  penetrating into the coupling opening  19  of the rotation transmission unit  18 . 
     The operation of the grinding device  1  by a user is described hereafter. The user moves the actuating device  11 , preferably manually, in the direction toward the coupling element  14 . As a result of the movement of the rotationally-fixed actuating device  11 , the rotationally-fixed spindle nut  15  also moves in the direction toward the coupling element  14 . More precisely, the actuating device  11  first penetrates into the cavity of the housing  13  and then comes into contact with the spindle nut  15 . Alternatively, it is conceivable that the actuating device  11  is already in contact with the spindle nut  15  in the non-actuated position. 
     The spindle  16  begins to rotate because of the contact of the spindle nut  15  with the thread of the spindle  16 . The rotational movement of the spindle  16  is transmitted via the rotation transmission unit  18  to the coupling device  31  of the work unit  30 . In this way, the work elements  32  located inside the container  40 , such as grinding elements, are rotated. The spindle nut  15  is moved in the direction toward the coupling element  14  until the spindle nut  15  and/or the actuating device  11  strike against a stop element. It can be ensured by the spring  17  that the spindle nut  15  and actuating device  11  are displaced back into the starting location shown in  FIG. 1 , if the locking device is not actuated in order to prevent this. 
     LIST OF REFERENCE NUMERALS 
     
         
           1  grinding device 
           10  drive device/spindle drive device 
           11  actuating device 
           13  housing 
           14  coupling element 
           15  rotation generation unit/spindle nut 
           16  spindle/drive unit 
           17  spring 
           18  rotation transmission unit 
           19  coupling opening 
           20  partition unit 
           21  partition element 
           22  recess 
           23  opening 
           30  work unit 
           31  coupling device 
           32  work element 
           40  container 
           41  mounting element