HK1058746B - Hand mixer or hand blender comprising a coupling device - Google Patents

Description

Hand-held or insertion-type stirrer with coupling device

Technical Field

The invention relates to a hand-held or plug-in mixer having a coupling device.

Background

In the art, a number of hand-held or plug-in mixers with coupling devices are already known. Suitable coupling means are usually used for fixedly mounting the drive shaft coupled to the motor part, as opposed to the tool shaft mounted on the attachment in the longitudinal direction of the shaft. In this way, a torque can be transmitted from the drive shaft to the tool shaft and thus to the tool of the attachment. In this arrangement, half of the flange connections of the coupling device are fixedly connected to the motor part and the other half of the flange connections are fixedly connected to the attachment device. One known way of connection is herein to use a threaded coupling between two parts to be coupled.

Another coupling device is disclosed in the patent FR 1467108. In accordance with this disclosure, in a hand held cookware application, a stirrer in the form of an attachment is inserted on an elongated housing of a motor assembly. In this application, the tool shaft is mounted in an axially fixed position relative to the drive shaft by means of a stationary housing part of the attachment. The housing part of the attachment is coupled to the housing of the drive part by means of a snap lock. By arranging the clamping member on the device, a snap lock can be formed under the action of a spring force applied inwards in the direction of the circular charging opening. The cylindrical coupling portion of the accessory member has an annular groove in which the clamping member can be captured. The tool shaft itself is inserted into the opposite drive shaft coupling transmission by means of its engaging coupling end. The coupling detent can be formed by an internal gear sleeve. The attachment means may be disengaged by depressing an ejection means in the form of a button formed in the housing of the drive member. The attachment is disengaged because the clip member is released from the annular groove and returned to its original shape. This also causes the engaged shaft end of the tool shaft to withdraw from the coupling device.

Another coupling device for a cooking appliance is described in EP-0692215 a 1. This specification discloses a hand mixer in which a tool wheel shaft comprising a tool shaft is coupled to a motor part of the hand mixer and can be disengaged. In order to achieve this, provision is made in the motor part, perpendicular to the drive shaft, for an approximately U-shaped expansion chuck which engages in a mounting groove in the tool spindle. The free end of the expansion chuck is in contact with the expansion surface. To decouple the motor element from the tool spindle, the expansion chuck is moved by a push button. The free end is then slid along the expansion surface so that the posts of the expansion chuck are forced apart from the mounting slots, thereby decoupling the motor member from the tool hub and separating the members from each other. In terms of parts and assembly, the configuration of the expansion surfaces required to open the expansion chuck and the push buttons required to actuate the expansion chuck represent the actual force.

Finally, another coupling device for a cookware appliance is disclosed in DE 20006028U 1. In this disclosure, the coupling between the motor housing and the axle component can be achieved by machining the clamping element on an elastic material. The preferred construction is one in which the resilient material is plastic, in effect forming a frame having one longer and one shorter axis. It is thus possible to form a clamping coupling between the housing parts and to uncouple it by actuating the protruding button part. With this coupling, the stationary housing part is fixed in the position of the longitudinal axis of the shaft. By means of the meshing coupling, the torque of the drive shaft can be transmitted to the tool shaft.

A disadvantage of the coupling device in the described cookware appliance is that, on the one hand, the handling is laborious, e.g. using a screw coupling, there is always a risk of tilting of the screw parts; on the other hand, the number of movable parts is too large, for example, in a case where the coupling member has a separate clamping member, a spiral spring and an actuating button.

Disclosure of Invention

It is an object of the present invention to provide an improved hand held or insertion mixer which includes a coupling device. The coupling and uncoupling of the attachment from the drive member should be very easy and not require a great force. Such a coupling device should be simple to manufacture and inexpensive.

According to the present invention there is provided an improved hand held or inserted mixer comprising a coupling device for uncoupling a shaft with a working tool from an electrically driven part, having an upper coupling part arranged on the driving part, having locking means, and a lower coupling part arranged on the tool shaft, having retaining means for enabling the coupling device to be axially locked, characterised in that the locking means are formed by spring-like retaining projections projecting radially outwards and the retaining means are formed by slots in the inner circumference of the lower coupling part, the upper coupling part being twisted relative to the lower coupling part so as to be able to be uncoupled.

With the present invention, coupling or uncoupling of the accessory part to or from the drive part can be easily achieved using a simple insertion/uncoupling action, and without requiring too much force. The holding projection enters the slot on the inner circumference of the lower coupling part by a simple insertion movement, so that the upper coupling part is axially locked in the axial direction. The coupling of the hand-held or plug-in agitator of the invention requires only few components and does not require the installation of any additional drive components, which is simple and economical to manufacture. And it is possible to make the housing structure smooth and easy to clean.

It is of course also possible to fit the projection on the lower coupling part and to provide the slot on the upper coupling part easily without departing from the spirit of the invention, i.e. this result is a comparable solution.

Preferably, a slide rail is formed around the insertion groove, and the grip protrusion slides along the slide rail after the upper coupling part is inserted into the lower coupling part, and the protrusion is elastically pressed inward during the assembly process. In this arrangement, the slide rail is formed with a regularly upward curl. Thus, when the upper coupling part is inserted into the lower coupling part, for example, the catching projection is elastically pressed inward in the radial direction in advance, the catching projection slides along the slide rail so as to be able to be inserted into the first position.

Preferably, the rail is of half-moon or U-shaped configuration. This form-fit design ensures in a surprisingly simple manner that the holding projection is reliably locked in place irrespective of its direction of approach to the slot in which the projection is placed.

Preferably, the upper and lower coupling parts include shoulders and sliding supports that axially move the two parts apart from each other when they are twisted. Thus, when the two coupling parts are twisted relative to each other, they can be reliably moved in the axial direction, that is, the two parts can be separated.

Preferably, there is a groove gripping edge on the inside of the slide rail, enabling a reliable locking action.

Preferably, the front side of the holding protrusion has a rounded or beveled edge to facilitate sliding movement of the holding protrusion along the slide rail.

Preferably, the holding projection has a corresponding holding hook between the front side and the upper side of the projection, which enables the holding projection to be locked onto the holding edge of the holding socket in which the projection is placed.

Preferably, a shoulder is formed on the upper coupling portion and a sliding support is formed on the lower coupling portion, the shoulder and the sliding support including wave-shaped fitting surfaces which are in face-to-face contact with each other in a state in which the assembly is completed. In this configuration, the wave shape, together with the sliding track defined by the positioning of the projecting slots, allows the coupling to be disengaged by a simple "uncoupling" action. Further, the appropriate wave shape determines the position of the upper coupling part relative to the lower coupling part in the coupled state, that is, the fail-safe function can be established.

Preferably, the upper coupling part has a cylindrical guide sleeve which can be placed inside the lower coupling part. This feature facilitates concentric mounting of the upper coupling part relative to the lower coupling part and allows relative twisting.

Preferably, the guide sleeve is made of a plastic material and has a slit at the free end for forming the spring member, from which the holding projection projects. It is thus possible to manufacture the part by a simple, low-cost plastic injection moulding process, which can be used as a finishing process when elastic clamping protrusions are required and included.

Preferably, the upper and lower coupling parts are made of a thermoplastic material. Thus, a low cost, easy to clean, sanitary and impact resistant structure can be manufactured. It will of course be appreciated that other suitable materials are also contemplated.

Drawings

Further structures and advantages of the invention will be explained in the following structural description, so that reference must be made to the attached drawings. In the drawings:

FIG. 1 is a perspective view of one construction of the coupling device of the present invention used in a cooker.

Fig. 2 is a view of fig. 1, section II.

Fig. 3 is a view of fig. 1, section III.

Fig. 4 is a partial cross-sectional view taken along line IV-IV of fig. 3.

Fig. 5 is a partial cross-sectional view taken along line V-V of fig. 2.

Fig. 6, 7 and 8 are three schematic views of the coupling device of fig. 1, showing different steps in the coupling process.

Fig. 9 and 10 are schematic views of the upper half of the flange joint of the structure of fig. 1, each rotated 90 °.

Fig. 11 is a perspective view of the coupling device of fig. 1.

Figure 12 is a schematic cross-sectional view of the coupling device of figure 11 taken along line XII-XII.

Detailed Description

Fig. 1 shows a perspective view of a coupling device 1. A schematic view of a completely hollow cylindrical upper coupling part 2 is provided, the upper extension of which is located inside the drive part of the plug-in mixer, which is not shown in the figures. Also shown is a lower coupling part 3 of similar, completely hollow cylindrical construction, the extension of which is within the respective appendage of the plug-in mixer, which mixer is likewise not shown in the figures. In the present structure, both the upper coupling portion 2 and the lower coupling portion 3 are made of a thermoplastic material. A drive shaft, not shown in the figure, extends in a concentric manner to the upper coupling part 2. The tool shaft, not shown, extends in a concentric manner to the lower coupling part, which part is likewise not shown.

The upper coupling part 2 has a smooth outer shell 4, the outer shell 4 having a lower shoulder 8 with a wave-shaped sliding surface 22. The sliding surface 22 extends in a direction completely transverse to the longitudinal axis 25 of the upper coupling part 2. Adjoining the shoulder 8 is a smooth cylindrical guide sleeve 5 which has a smaller diameter than the housing 4. The shaft shoulder 8 is a wavy curved surface. A similar cylindrical guide sleeve 5 comprises spring members 10, each spring member being offset 180 ° and supporting a gripping protrusion 11. In the present configuration, the holding projection 11 is likewise made of thermoplastic material and projects radially beyond the circumference of the guide sleeve 5.

The spring member 10 and the holding projection 11 are partially represented and shown in an enlarged scale in fig. 2. The edge 21 between the front side of the holding projection 11 and the projection surface 13 and the underside 15 of the holding projection 11 is of rounded or beveled construction. The edge 26 between the upper side and the front side 18 of the holding projection 11 is shaped with the holding hook 14, that is to say it projects like a barb on the tip of the holding projection 11. Further, in fig. 5 a section along the line V-V is shown, again illustrating the basic structure of the guide sleeve 5 with the spring element 10 separated from the guide sleeve 5 by a lateral groove 24 and thus connected thereto only at the upper end portion 28 (fig. 9).

Fig. 1 also shows a schematic perspective view of the lower coupling part 3. The lower coupling part is in this figure completely machined to a hollow cylindrical shape with a sliding surface 23 at its upper end, machined to the sliding support 9. The sliding support 9 has a wave-shaped configuration, cooperating with the shoulder 8 of the upper coupling part 2, that is to say, in the inserted state, the two sliding surfaces 22, 23 are in contact with each other, forming a slit 27 (fig. 11). The sliding surfaces 22, 23 extend circumferentially around the parts 2, 3.

A half-moon shaped slide rail 12 offset by 180 is arranged on the smooth inner wall 6 of the lower coupling part 3. The slide rail 12 is shown on an enlarged scale in fig. 3, in fig. 1 in detail III. Below the slide rail is a placement of a protruding socket 16 in the shape of a circular socket or groove. The inner diameter of the lower coupling part 3 is dimensioned just enough to place the guide sleeve 5 of the upper coupling part 2.

Further, the outer wall 7 of the lower coupling part 3 is configured to be bent together with the housing 4 of the upper coupling part 2 in the coupled state.

As mentioned above, fig. 3 shows the detail III of fig. 1. The configuration of the half-moon shaped sliding rail 12 is similar to a lying U, that is to say the two upright sides are directed downwards and the curved section is directed upwards in the direction of the upper coupling part 2. The width of the slide rail 12 remains constant. The lower edge of the slide rail 12, i.e. the inner side of the U forming the clamping edge 17, forms a smooth projection or slot adapted to be contacted by the contact hook 14 of the clamping projection 11. As is clear from the view of fig. 3, the two legs of the U terminate approximately in a plane perpendicular to the cylindrical axis of the lower coupling part. The basic structure can be further seen in the section taken along line IV-IV in fig. 4. This view particularly shows the slide rail 12 and the placement tab slot 16.

Fig. 6, 7, 8 show three steps of the coupling operation, which will be explained below.

Fig. 6 shows a coupling device 1 comprising an upper coupling part 2 and a lower coupling part 3, the upper coupling part 2 being inserted into the lower coupling part 3 according to the direction of arrow a. The wavy top of the shoulder 8 of the upper coupling part 2 and the sliding support 9 of the lower coupling part 3 have a face-to-face relationship with each other. A guide sleeve 5, having a smaller diameter than the outer wall 4 of the upper coupling part 2, is partly placed inside the lower coupling part 3. Further, a gripping projection 11, which is offset by 180 °, protrudes from the spring element 10 of the upper coupling part 2, which is not visible in the drawing, up to the left or right side of the guide sleeve 5.

With a small force applied in the direction indicated by arrow a, the upper coupling part 2 is now twisted in the direction indicated by arrow B, while the lower coupling part 3 is clamped tightly. The shoulder 8 of the upper coupling part 2 slides along the sliding support 9 of the lower coupling part 3 during assembly, i.e. the "wave-shaped top" of the shoulder 8 slides in the "wave-shaped channel" of the sliding support 9.

Fig. 7 shows the next step of the coupling operation, in which the upper coupling part 2 and the lower coupling part 3 have been partly twisted relative to each other, i.e. the "wave-shaped top" of the shoulder 8 of the upper coupling part 2 has entered the "wave-shaped channel" of the sliding support 9 of the lower coupling part. As already shown in fig. 6, the upper coupling part 2 is moved downwards in the direction of arrow a. The guide sleeve 5 moves deeper and deeper down into the lower coupling part 3.

Fig. 8 shows the connecting device 1 before entering the fully coupled state. In the coupled state, the shoulder 8 and the sliding support 9 correspond to each other, i.e. the wavy shape of the shoulder 8 and the sliding support 9 correspond to each other. This and the operation of the sliding sleeve 5 make the two half-flange joints concentric with each other. The outer wall 4 of the upper coupling part 2 and the outer wall 7 of the lower coupling part 3 are curved together with their surfaces. The bend of the guide sleeve 5 disappears entirely within the lower coupling part 2.

In this arrangement, the gripping protrusions 11 are of resilient construction, that is to say, during the coupling operation, initially disappear completely within the profile of the guide sleeve 5 when the remaining coupling parts 3 of the upper coupling part 2 come into contact with one another, as shown in fig. 6. When the upper coupling part 2 is twisted relative to the lower coupling part 3, the depressed clamping protrusion 11 slides along the inner wall 6 of the lower coupling part 3 until it reaches one of the posts of the half-moon shaped sliding rail 12. The spring-loaded holding projections 11 slide upwards on the slide rails 12 until they finally enter the placing projection insertion slots 16. When this occurs, the gripping protrusions 11 come into contact with the gripping hooks 14 in the slots of the gripping edge 17 where the protrusion slots 16 are placed. This condition is created when the shoulder 8 of the upper coupling part 2 is fully resting on the sliding support 9 of the lower coupling part 3.

Now the coupling device 1 is completely coupled together, that is to say the upper coupling part 2 and the lower coupling part 3 are completely coupled together. The attachment is thus locked on the drive part in the axial direction.

The coupling slot may also be achieved by placing the upper 2 and lower 3 coupling parts against each other so that the "wave-shaped top" of the shoulder 8 and the "wave-shaped channel" of the sliding support 9 already correspond to each other. In this case, the upper coupling portion 2 and the lower coupling portion 3 only need to be moved toward each other in the axial direction. When the guide sleeve 5 enters the lower coupling part 3, the holding projection 11 is pressed inward by the inner wall 6 of the lower coupling part 3. When the shoulder 8 is placed down on the sliding surface 9, the holding projection 11 springs into the holding projection insertion slot 16, where the holding hooks 14 of the holding projection 11 lock with the holding edges 17. This locks the coupling device 1 in the axial direction.

For uncoupling, the description of the coupling operation with reference to fig. 6 to 8 is made in the opposite direction. This involves twisting the upper coupling part 2 relative to the lower coupling part 3. The underside 15 or one of the projecting sides 13 of the holding projection 11 is moved upwards along the slide rail until a position is reached in which the holding hook 14 of the holding projection 11 is no longer in contact with the holding edge 17 of the holding projection socket 16. The clamping projection 11 thus slides over a rounded or beveled corner between the front side 18 of the clamping projection 11 and the projection flank 13 projecting out of the groove-shaped receptacle in which the projection receptacle 16 is located and is pressed down by the spring force of the spring member 10, which is in turn on the guide sleeve 5 of the upper coupling part 2. The upper coupling part 2 can then be simply twisted off by means of the wave-shaped shoulder 8. As a result, a configuration called "insertion/disengagement" is achieved.

Fig. 9 to 10 show two schematic views of the upper coupling part 2, each rotated by 90 °. They show the housing 4 and the guide sleeve 5. Also shown in fig. 9 is a spring member 10 which extends over the guide sleeve 5 parallel to the longitudinal axis of the coupling device, and from which a holding projection 11 projects at an acute angle. The smaller diameter of the guide sleeve 5 relative to the outer wall 4 of the upper coupling part 2 is also clearly shown. The shoulder 8 between the housing 4 and the guide sleeve 5 is formed by a wave-shaped sliding support.

Fig. 11 shows a schematic view of the coupling device in a coupled state. In this state, the shoulder 8 of the upper coupling part 2 is completely placed on the sliding support 9 of the lower coupling part 3.

Figure 12 shows a schematic cross-sectional view of the coupling device of figure 11 taken along section line XII-XII. On the upper coupling part 2 there is a completely cylindrical sleeve 19. The sleeve 19 is placed against the inner wall 20 of the upper coupling part 2. The sleeve 19 has the spring element 10 formed together as one piece construction. At the lower end of the spring member 10, a portion where the holding projection 11 projects by being deviated by 180 ° is provided. In this configuration, the sleeve 19 is made of a resilient plastics material.

Further, the sectional view of fig. 12 schematically shows the lower coupling part 3 having a holding edge 17 at a portion where the protrusion insertion groove 12 is placed, with which the holding hook 14 of the holding protrusion 11 comes into contact to form a locked state.

Claims (11)

1. A hand-held or plug-in mixer, comprising a coupling device (1) for separating a shaft with a working tool from an electric drive part, having an upper coupling part (2) arranged on the drive part, having locking means, and a lower coupling part (3) arranged on the tool shaft, having clamping means for axially locking the coupling device (1),

characterised in that the locking means are formed by spring-like gripping protrusions (11) extending radially outwards and the gripping means are formed by slots (16) in the inner circumference of the lower coupling part (3), the upper coupling part (2) being twisted relative to the lower coupling part (3) so that the coupling can be released.

2. A hand-held or plug-in mixer according to claim 1, characterised in that a sliding track (12) is formed around the receptacle (16), along which the holding projection (11) slides when the upper coupling part (2) is inserted into the lower coupling part (3), the projection being pressed resiliently inwards during assembly.

3. Hand-held or insertion-type agitator as claimed in claim 2, characterized in that the sliding rail (12) is of half-moon or U-shaped construction.

4. A hand-held or insertion-type whisk according to claim 1, characterised in that the upper coupling part (2) and the lower coupling part (3) comprise shoulders (8) and sliding supports (9) which, when the two parts are twisted, move the two parts (2, 3) axially away from each other.

5. A hand-held or plug-in mixer as claimed in claim 2, characterized in that the slide (12) has a recessed holding edge (17) on the inside.

6. Hand-held or insertion-type stirrer according to one of the preceding claims, characterised in that the front side (18) of the clamping projection (11) has a rounded or beveled edge (21).

7. A hand-held or plug-in mixer according to claim 6, characterised in that the gripping protrusions (11) have corresponding gripping hooks (14) between the front side (18) and the upper side of the protrusion.

8. A hand-held or plug-in mixer according to claim 4, characterised in that the shoulder (8) is formed on the upper coupling part (2) and the sliding support (9) is formed on the lower coupling part (3), the shoulder (8) and the sliding support (9) comprising wave-shaped co-operating surfaces (22, 23) which, in the assembled state, are in face-to-face contact with each other.

9. A hand-held or insertion-type stirrer according to any one of claims 1 to 5, characterised in that the upper coupling part (2) has a cylindrical guide sleeve (5) which can be placed inside the lower coupling part (3).

10. A hand-held or insertion-type whisk as claimed in claim 9, wherein the guide sleeve (5) is made of a plastic material and has a slit at the free end for forming the spring member (10), from which the holding projection (11) protrudes.

11. A hand-held or insertion stirrer according to any one of claims 1 to 5, characterised in that the upper coupling part (2) and the lower coupling part (3) are made of a thermoplastic material.