CA1118408A - Safety lock-switch system for household blenders - Google Patents

Safety lock-switch system for household blenders

Info

Publication number
CA1118408A
CA1118408A CA000325910A CA325910A CA1118408A CA 1118408 A CA1118408 A CA 1118408A CA 000325910 A CA000325910 A CA 000325910A CA 325910 A CA325910 A CA 325910A CA 1118408 A CA1118408 A CA 1118408A
Authority
CA
Canada
Prior art keywords
lock
motor base
bars
motor
levers
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
CA000325910A
Other languages
French (fr)
Inventor
Johannes Grandel
Gunther Falkenbach
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Braun GmbH
Original Assignee
Braun GmbH
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from DE2817044A external-priority patent/DE2817044C3/en
Priority claimed from DE2904498A external-priority patent/DE2904498C2/en
Application filed by Braun GmbH filed Critical Braun GmbH
Priority to CA000364760A priority Critical patent/CA1116593A/en
Application granted granted Critical
Publication of CA1118408A publication Critical patent/CA1118408A/en
Expired legal-status Critical Current

Links

Classifications

    • AHUMAN NECESSITIES
    • A47FURNITURE; DOMESTIC ARTICLES OR APPLIANCES; COFFEE MILLS; SPICE MILLS; SUCTION CLEANERS IN GENERAL
    • A47JKITCHEN EQUIPMENT; COFFEE MILLS; SPICE MILLS; APPARATUS FOR MAKING BEVERAGES
    • A47J43/00Implements for preparing or holding food, not provided for in other groups of this subclass
    • A47J43/04Machines for domestic use not covered elsewhere, e.g. for grinding, mixing, stirring, kneading, emulsifying, whipping or beating foodstuffs, e.g. power-driven
    • A47J43/046Machines for domestic use not covered elsewhere, e.g. for grinding, mixing, stirring, kneading, emulsifying, whipping or beating foodstuffs, e.g. power-driven with tools driven from the bottom side
    • AHUMAN NECESSITIES
    • A47FURNITURE; DOMESTIC ARTICLES OR APPLIANCES; COFFEE MILLS; SPICE MILLS; SUCTION CLEANERS IN GENERAL
    • A47JKITCHEN EQUIPMENT; COFFEE MILLS; SPICE MILLS; APPARATUS FOR MAKING BEVERAGES
    • A47J43/00Implements for preparing or holding food, not provided for in other groups of this subclass
    • A47J43/04Machines for domestic use not covered elsewhere, e.g. for grinding, mixing, stirring, kneading, emulsifying, whipping or beating foodstuffs, e.g. power-driven
    • A47J43/06Machines for domestic use not covered elsewhere, e.g. for grinding, mixing, stirring, kneading, emulsifying, whipping or beating foodstuffs, e.g. power-driven with a plurality of interchangeable working units, e.g. with a single driving-unit
    • AHUMAN NECESSITIES
    • A47FURNITURE; DOMESTIC ARTICLES OR APPLIANCES; COFFEE MILLS; SPICE MILLS; SUCTION CLEANERS IN GENERAL
    • A47JKITCHEN EQUIPMENT; COFFEE MILLS; SPICE MILLS; APPARATUS FOR MAKING BEVERAGES
    • A47J43/00Implements for preparing or holding food, not provided for in other groups of this subclass
    • A47J43/04Machines for domestic use not covered elsewhere, e.g. for grinding, mixing, stirring, kneading, emulsifying, whipping or beating foodstuffs, e.g. power-driven
    • A47J43/07Parts or details, e.g. mixing tools, whipping tools
    • A47J43/075Safety devices
    • A47J43/0761Safety devices for machines with tools driven from the lower side
    • A47J43/0772Safety devices for machines with tools driven from the lower side activated by the proper positioning of the cover

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Food Science & Technology (AREA)
  • Food-Manufacturing Devices (AREA)
  • Crushing And Pulverization Processes (AREA)

Abstract

ABSTRACT
Electric household blender having a base enclosing a motor to drive the tools of an auxiliary unit such as a carved element, wherein the auxiliary unit is anchored by lock bars arranged thereon to bolts provided on the base. The bolts can be rotatably moved together with a ring mounted on the base for the purpose of locking, which ring, in turn, cooperates with an operating switch to turn the drive motor on and off and with a positioning member, lock rod and lock fork. The lock bars are either rigidly arranged on the auxiliary unit and formed in two pieces, or formed as one-piece, double-bent, flat pushers mounted in a movable manner in the housing of the auxiliary unit. The operating switch and the lock bars can only be activated when the lock bolts have first entered into the recesses or lock bar in such a manner that the auxiliary unit is nonremovably locked in place.

Description

Description Electric Household Blender Ihe invention relates to an electric household blender having an attachable device in which cutting tools driven by a motor rotate, and a motor base with an electric switch.
In known devices of this type, if the material to be processed in the container is quite thin, the rotor often continues to rotate for several seconds after being turned off. If the user is not careful, he runs the danger of placing his hand in the container too early, before the blades have stopped, and severely injuring himself.
In order to protect the user of a household blender from ; in~ury by the still rotating blades, it has already been proposed (German Publication 2,228,189, Mantelet, August 30, 1973) to close the control circuit of a brake device of the motor as soon as the lid is removed from the container with the material to be processed. For this purpose the electrical circuit of the drive motor includes one or more switches connected in series, whose movable switch ele~ent can assume either an operating position in which the electrical circuit is closed, or a rest position in which this electrical circuit is open, whereby the movable switch element has one contact which in the rest position closes the control circuit of the brake device of the motor.
Moving the switch out of the brake position to turn the blender on is effected by pressing the lid against the container. ~his known blender has the disadvantage that the user must continually press the lid of the device downward durlng operation, and cannot leave it unattended.
Furthermore, the known blender cannot be combined with auxi]iary units such as a mixer, citrus press or meat grinder, because these units require a firm anchor with the motor base.
me ob~ect of the present invention is to provide an electric household blender in ~hich, after the motor is turned off, all danger of injury from still rotating blades is eliminated and which allows the provision of auxiliary units. The apparatus is formed such that the user of the blender need not remain next to the apparatus during its operation.
Finally, the type of interlockLng mechanism for the attachable device is formed such that the attachable device can have a different free diameter than that of the motor base.
According to the invention there is provided an electric household blender, comprislng; a mountable apparatus having a housing and a lid, and a motor base provided with a motor and an electric switch, said apparatus being mountable on said motor base and having cutting tools adapted to be driven by said motor, a holder for hold m g said apparatus to said base, said holder in-cluding lock bolt supports, a lock ring provided with lock bolts and being held and guided in said motor base for rotation about a longitudinal axis thereof, said lock ring belng provided with a lock bar for rotating said lock ring, said switch being engaged with a longitudinally mo~eable lock rod for selectively preventing operation of 5aid switch in dependence upon the pos-ition of said lock ring, wherein said lock bolt supports comprise urther lock bars having truncated ends, said urther lock bars being guided next to said housing and being moveable against a biasing orce, lock levers co-operating with said further lock- bars, said lock levers being pivotably mount-ed in said housing, said lid having ~ number of apertures, and said lock levers having free ends passing through said apertures when pivoted.
The motor base and container holder are advantageously provided with guide surfaces, whereby the container holder has lock openings or slots in the vicinity o the guide surfaces as C

4~t3 lock bolt supports, in which lock bolts or studs engage. These lock bolts or studs are arranged on the movable lock ring and are supported and guided in openings in the housing of the motor base.
The container is advantageously provided with guide surfaces, at least two of which are arranged so as to be distri-buted on the circumferential surface, whereby each locking pocket is provided with a locking groove or locking slot and the locking pockets are enclosed in corresponding depressions equipped with guide surfaces, which are provided on the motor base.
In one exemplary embodiment in which the attachable device has a substantially larger diameter, the lock bolt supports et the top and bottom are truncated bars which .

-2a-!'X ~ "
, ., ., _ ~, 340~

are held and guided next to the housing of the apparatus and are per~endicularly movable against spring force and cooperate with tilt-able levers mounted in the housing, the free ends of which levers enter into openings in the side wall of the lid when the bar is pushed downward.
By means of the apparatus according to the invention, it is assured that the apparatus can only be turned on when the container for the material to be blended or an auxiliary unit is placed on the motor base and is rigidly locked thereto. The unlocking procedure and subsequent removal of the container holder requires so much time that the motor will surely have stopped before contact with the tools or blades is possible.
Ihe invention allows a wide variety of possible embodiments.
Two of these are sche~atically illustrated in the attached drawings, wherein:
Figures 1 and 2 show an electric household blender in perspective view, whereby the holder for the container for receiving the material to be blended is shown separately from the motor base;
Figure 3 shows a partial section through the blender, whereby the device for locking the container holder, part of the con-tainer and the container locked by the container holder are shown in section. The motor and wing blades are not depicted for better visibility;
Figure 4 shows a perspective partial illustration of the container holder with interlocking pocket;
Figure 5 shows a perspective partial illustration of the motor base;
Figures 6 and 7 show a schematic and perspective illustration of the basic parts of the device for locking the container holder to the motor base;
Figure 8 shows the motor base of the kitchen appliance according to Figure 1 in front view;
Figure 9 shows a back view of the motor base according ,, - to Figure 8;
Figure 10 shows an enlarged partial section through the motor base with attached carved element;
Figure 11 shows a longitudinal section of the lid of the carved element according to Figure 10;
Figures 12, 13 and 14 show various views of the lock bar to hold the carved element on the motor base; and Figures 15 and 16 show various views of the lock lever to lock the lid of the carved element.
The container 1, together with the container lid 10, is held by a container holder 2 between the edge 20 of the container holder 2 on one side ~nd the motor base 4 on the other side. In order to be able to lock the container 1 with lid 10 to the motor base 4, said holder 2 has three interlocking pockets 5 with ~uide surfaces 35, 36 37 uniformly distributed about its circumference. These guide surfaces are equipped with respective perpendicular pins 7 and a lock bolt support 12 (Fig. 4). When the holder 2 is placed on the motor base 4, the pins 7 move in the diredtion A of the arrows (Fig. 4) and press against the loc'c bolts 8, three of which are distributed on the circumference of a lock ring 9 arranged in the inside of the motor base 4, and thus make the interlocking mechanism (shown in Figs. 6 and 7) activatable.
After placement of the hclder 2 and movement thereof in the direction A, the lock ring 9 which is movabl~T
mounted in the motor base 4 (Fig. 6) is pushed by the pins 7 in direction A against the force of springs 16. If the lock ring 9 is then rotated in direction C by the lock bar 11, the lock bolt 8 becomes enclosed in the lock bolt 8upport 12 (Fig. 7). The horizontally arranged lock bolts 8 are held and g~ided for this purpose in L-shaped longitudinal holes 1- cut in the housing wall of the motor base 4. The loc~ ring 9 also has three longitudinal holes 17 distributed about its circumference whereby a screw 14 with spring 16 passes through each of these longitudinal holes 17, which screws 14 are attached 40t:~
, at 15 to the motor base 4. The springs 16 press the lock ring 9 upward against arrow direction A.
On the outside wall of the motor base 4 in the area of the L-snaped longitudinal holes 14, downwardly open guide studs 30 (Fig. 5) with bores 28 are provided for the pins 7 of the interlocking pockets 5 so that they exactly meet the lock bolts 8 of the lock ring 9 when the container holder 2 is placed on the motor base 4. As shown in Figs. 6 and 7, the lock ring 9 can be moved in direction C
or D with the aid of the lock bar ll, which is guided in a longitudinal hole (not shown n greater detail) present in the housing wall of the motor base.
In addition to a stud 24, with which it is enclosed in a recess 43 of the lock ring 9, the lock bar ll also has a lock fork 25 which acts together with the lock rod 26 movable in a perpendicular diJre~ion in the motor base f 4 and in which, in turn, the L~d 2~ vf the operating switch engages. When the lock ring 9 is in the position shown in Fig. 7, i.e., when the holder 2 is locked by the bolts 8 and the lock bolt supports 12 after the lock bar ll is moved in direction C, the lock rod 26 ~an be moved vertically upward in direction E by rotating the operating switch 27-in direction G, so that the lock rod 26 enters into the recess 29 of the lock fork 25. Only in this position (Fig. 7) can the operating switch 27 be roltated and the motor be turned on to drive the wing blades. If the operating switch 27 is rotated opposite direction G, the lock rod 26 falls vertically downward against the direction E, so that the lock bar ll can be moved in direction D. After the lock bar ll is moved in direction D (Fig. 6), the lock rod 26 is locked, because one end thereof abuts the shoulder 23, which renders the operating switch 27 incapable of rotating.
The exemplary embodiment of the holder 2 shown in Fig. 3 is not only suited to hold a lid on a container and lock both parts (10 and l) to the motor base 4, but rather the container l with lid 10 can be exchanged for 111~408 a mixing unit, a meat grinder or a citrus press. These auxiliary units only require a base portion which corresponds in diameter d and height h (Figure 3) to the illustrated container 1 and lid 10. Because the holder 2 is provided on its upper side with an opening ~, parts of the auxiliary units can be formed in such a manner that they project far beyond the holder 2. Finally, container holders can be provided whose dimensions h and 8 are such that, for example with a mixing unit, it is impossible for the user to reach the rotating blades with the h~nd or fingers from the top through the opening. The inner surfaces of the holder are effectively provided with ribs, cams or the like (not shown), which reliably prevent the holder or the auxiliary unit from rotating about the blade axis when the motor is turned on. The electrical control portion in the motor base may also be provided with a known braking device; thus when the motor is turned off, the control circuit of a braking device is closed so that the motor instantaneously comes to a halt Instead of an electrically operating braking device, the lock bar 26 can also be coupled with a mechanically operating motor brake. As soon as the lock bar moves opposite the arrow direction E, i.e., when the motor is turned off, it presses a brake shoe (not shown) against the motor shaft.
In the household blender according to Figure 3, a container is placed on the motor base. In place of this container, in the dev~ce according to Flgure 10, the motor base is combined with a carbed element.
Lock bolts 8, which serve to lock the unit placed on the motor base 4, in this case the carved element 50, project radially outward through the L,shaped slots 17a, 17b, 17c of the motor base (Figures 8 and 9). The lock bolts 8 are connected with a positioning member 24 by the linkage described in detail above, which positioning member 24 moves the lock bolts 8 in direction C (Figure 1) by movlng in direction D. To be capable of moving in direction C, the lock bolts must first be pushed downward (in direction A), which occurs with the aid of :~ - 6 -three lock bars 51 mounted on the carved element 50 as the carved element 50 is mounted.
Each lock bar 51 also has fingers 52 (Figure 10) which enter into guide slots 53a, 53b and 53c (Figures 8 and 9) provided in guide studs 70, 71, 72 on the motor base 4 and move the lock bolts 8 in direction A, so that the lock bolts 8 can be moved in direction C
(Figure 8) by the linkage, which is not shown in greater detail. Each of the three lock bars 51 is mounted and guided in the housing of the carved element so as to be capable of being pushed in direction E
against the force of a spring 54. As shown in Figures 10 and 13, each lock bar 51 has a truncated end 55, whereby each end 55 is also provided with an opening 56 in which the free end 57 of respective lock levers 58 engage, the other end of which is mounted in the carved element housing 50 so as to be pivotable about the rib 60.
If the carved element 50 with associated lid 73 is placed on the motor base 4, and after such mounting of the entire carved element 50/73 pressure is exerted in direction G on the lid, the three lock levers 58 connected with the lock bars 51, moved by the ribs 77 of the lid 73, pivot about the ribs 60 in direction H, whereby the free ends 57 of the lock lever 58 enter into the openings 62 beneath the ribs 77 in such a manner that a form-fitting connection arises between the lid 73 with the car~ed element 50 by means of the lock levers 58.
At the same time the lock levers 58 pivot in direction H
the lock levers 58 push the lock bars 51 in direction E against the force of the springs 54 until (distance sl) the lower edge 63 of the lid 73 abuts the collar 64 of the carved element 50. m e three lock bars 51 thereby move by almost the same distance s2, and the fingers 52 thereof engage in openings 53a, 53b and 53c in the guide studs 70, 71, 72 on the motor base 4 and press the lock bolts 8 downward in direction A. Now the three lock bolts 8 can be pushed by moving the positioning m~n~er 24 simultaneously in directions D and C

340~3 (circumferential direction) by means of the lock ring 9 which is mounted in the motor base 4, whereby the lock bolts 8 slide into the vertical slots 17a, 17b and 17c and simultaneously become enclosed in the hooks 65 at the lower ends of the lock bars 51 in such a manner that the lock bars 51 and thereby the entire carved element including lid 73 are firmly held on the motor base 4.
The interlocking appara~us located in the motor base 4 is formed in such a manner that the operating switch 27 for turning the motor on and off can only be rotated when the positioning member 10 24 is moved in direction D and at the same time the lock bolts 8 are pushed in direction C. Complete safety from unintentional con~act with the cutting tools 79 of the friction disc 78 results in that all lock bolts 8 can only be pushed by the positioning member 24 when the apparatus 50 including lid 73 have been mounted on the motor base 4 and pressed downward against spring force.
The ~otor can also not be turned on if only the part 50, i.e., without the lid 73, is mounted because the lock lever 58 can then not be rotated out of its original position.

~, f - 8 -

Claims (5)

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. An electric household blender, comprising;
a mountable apparatus having a housing and a lid, and a motor base provided with a motor and an electric switch, said apparatus being mountable on said motor base and having cutting tools adapted to be driven by said motor, a holder for holding said apparatus to said base, said holder in-cluding lock bolt supports, a lock ring provided with lock bolts and being held and guided in said motor base for rotation about a longitudinal axis thereof, said lock ring being provided with a lock bar for rotating said lock ring, said switch being engaged with a longitudinally moveable lock rod for selectively preventing operation of said switch in dependence upon the position of said lock ring, wherein said lock bolt supports comprise further lock bars having truncated ends, said further lock bars being guided next to said housing and being moveable against a biasing force, lock levers cooperating with said further lock bars, said lock levers being pivotably mounted in said housing, said lid having a number of apertures, and said lock levers having free ends passing through said apertures when pivoted.
2. Electric household blender according to claim 1, characterized in that the lock levers pivot about horizontal axes and, when the lid is pressed down, push the lock levers together with the further lock bars effectively connected therewith in the closing direction.
3. Electric household blender according to claim 1, characterized in that the perpendicularly mounted and movable further lock bars have openings in the area of their upper outwardly truncated ends in which the free ends of the lock levers engage.
4. Electric household blender according to claim 1, characterized in that the further lock bars have fingers on their lower ends, which engage in slots for the purpose of locking, which slots are provided in the motor base, and in that hooks are provided adjacent the fingers.
5. Electric household blender according to claim 1, characterized in that the further lock levers are supported with their ends on ribs which are part of the apparatus, the lock levers abutting housing projections to pre-vent lateral shifting.
CA000325910A 1978-04-19 1979-04-19 Safety lock-switch system for household blenders Expired CA1118408A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CA000364760A CA1116593A (en) 1978-04-19 1980-11-14 Electric household blender

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
DEP2817044.7 1978-04-19
DE2817044A DE2817044C3 (en) 1978-04-19 1978-04-19 Electric household mixer chopper
DEP2904498.2 1979-02-07
DE2904498A DE2904498C2 (en) 1979-02-07 1979-02-07 Electric household mixer chopper

Publications (1)

Publication Number Publication Date
CA1118408A true CA1118408A (en) 1982-02-16

Family

ID=25774291

Family Applications (1)

Application Number Title Priority Date Filing Date
CA000325910A Expired CA1118408A (en) 1978-04-19 1979-04-19 Safety lock-switch system for household blenders

Country Status (10)

Country Link
EP (1) EP0004987B1 (en)
AR (1) AR219589A1 (en)
AT (1) AT368383B (en)
AU (1) AU526300B2 (en)
BR (1) BR7902446A (en)
CA (1) CA1118408A (en)
ES (1) ES480326A1 (en)
HK (1) HK64183A (en)
MX (1) MX145140A (en)
SG (1) SG40783G (en)

Families Citing this family (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0063241A1 (en) * 1981-04-03 1982-10-27 Braun Aktiengesellschaft Electrically powered driving device for food processors
EP0346598A1 (en) * 1988-06-11 1989-12-20 Braun Aktiengesellschaft Household appliance, especially a centrifugal juice extractor
US6609821B2 (en) 2001-04-13 2003-08-26 Sunbeam Products, Inc. Blender base with food processor capabilities
GB2426868B (en) * 2005-06-03 2008-01-09 Kenwood Marks Ltd Interlock system
FR2957508B1 (en) * 2010-03-22 2012-03-23 Seb Sa CULINARY PREPARATION ELECTRICAL APPLIANCE COMPRISING A MOTOR HOUSING FOR RECEIVING DIFFERENT TYPES OF REMOVABLE ACCESSORIES
FR2957509B1 (en) * 2010-03-22 2012-03-23 Seb Sa CULINARY PREPARATION ELECTRICAL APPLIANCE COMPRISING A BOX SUPPORTING A WORKING BOWL RECEIVING A FRAGMENTATION TOOL
FR2999404B1 (en) * 2012-12-14 2014-12-26 Seb Sa HOUSEHOLD APPLIANCE COMPRISING AN INTERNAL SEAL COVER
DE102015206935A1 (en) * 2015-04-16 2016-10-20 BSH Hausgeräte GmbH Thrust adjustment device with axial bearing for food chopping device and device for chopping food with passage adjustment device

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1205663B (en) * 1959-07-06 1965-11-25 Baumgarten K G Drive housing for various attachable domestic kitchen appliances with an electric motor that can be operated at several different speeds
FR2140891A5 (en) * 1971-06-11 1973-01-19 Moulinex Sa

Also Published As

Publication number Publication date
EP0004987B1 (en) 1981-09-02
HK64183A (en) 1983-12-16
AT368383B (en) 1982-10-11
AU526300B2 (en) 1983-01-06
ES480326A1 (en) 1979-11-16
BR7902446A (en) 1979-10-23
ATA270279A (en) 1982-02-15
AU4623379A (en) 1979-10-25
MX145140A (en) 1982-01-06
AR219589A1 (en) 1980-08-29
EP0004987A1 (en) 1979-10-31
SG40783G (en) 1985-02-15

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