DE9301160U1 - Spring-loaded hinge for front doors of household dishwashers - Google Patents

Description

EBHZ-91/59 .-. .··. .: .·*. "^5.01.1993

L ice &eegr; tia
Patent-Verwaltungs-GmbH . Frankfurt/Main

Spring-loaded hinge for front doors of domestic dishwashers

The innovation concerns a file-loaded hinge for the front doors of household dishwashers. In a narrower sense, it concerns an adjustable door weight compensation with an integrated movement braking device.

The front doors of most commercially available dishwashers can be swiveled or folded and have horizontal hinges arranged near the floor for an opening angle of approx. 90°. The front doors in question must engage securely and smoothly and must not fall too hard into the hinge when opened in order to avoid damaging the bearings. Furthermore, the front door, which is almost horizontal and located near the floor, must be able to be swiveled into the closed position by the user with minimal effort. On dishwasher types that can be integrated into kitchen units, the front doors in question are covered with so-called "decorative front panels" of various shapes, the weight of which varies. The movement behavior of the front door is determined by its weight. Adjustment devices are therefore provided which enable self-compensating spring counteractions to the weight of the door during opening and closing.

For this purpose, a "door hinge, in particular for household appliances" has become known from DE 40 27 931 A1. A tension spring that can be hooked onto the side of the housing body and is arranged vertically can be adjusted from above. The lower spring head is mechanically connected to the front door via hinged rod elements, triangular plates and various levers.

Furthermore, DE 36 18 740 C2 describes a "door hinge with

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Weight compensation for household appliances, especially for dishwashers". Here, the door bearing block is inserted into a U-shaped frame rail and locked into place. The tension springs of the door hinges, which can be adjusted from above, are arranged vertically and run along said vertical frame rails.

Both known designs require a large number of individual parts, such as rod elements, plates, various levers and stamped sheet metal parts. The manufacturing and assembly effort is considerable and extremely costly.

The innovation is based on the task of creating an inexpensive door hinge for household dishwashers that can be manufactured from a few individual parts and is easy to adjust.

According to the innovation, this problem is solved by the characterizing features of the subordinate, mutually independent claims.

The advantages that can be achieved through the innovation are already apparent from the nature of the task: simple manufacturing and the resulting reduction in costs. Other advantages include: Any intermediate door position desired by the user can be adjusted (i.e. equilibrium state of the door at any opening angle). The dimensional distances, door center of gravity - door pivot point or hinge point - door pivot point are selected so that relatively low spring forces are sufficient to operate mechanism ¹ .

Several embodiments of the innovation are shown in the drawings and are explained in more detail below.

It shows:

Fig. 1 a schematic representation of a dishwasher with the side wall removed, showing the pressure spring-loaded push rod guide and the front door hinged to it,

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Fig. 1a a possible intermediate door position in equilibrium,

Fig. 1b the front door in the final opening position,

Fig. 2 the compression spring adjustment device as detail "X" according to Fig. 1 in an enlarged view,

Fig. 3 shows a push rod modified compared to Fig. V,

Fig. 4 shows a simulated door movement sequence over its entire opening path using the pressure spring-loaded push rod drive according to Fig. 1,

Fig. 5 a dishwasher similar to Fig. 1, but with a tension spring loaded push rod guide and a front door hinged to it,

Fig. 6 is a sectional view along the line a-a according to Fig. 5 in an enlarged side view,

Fig. 7 a dishwasher similar to Fig. 1 or Fig. 5, but with a gas spring loaded door drive.

According to Fig. 1, a schematically illustrated household dishwasher 1 has a front door 3 that can be pivoted horizontally around the pivot point 2 for a maximum opening angle of approx. '90 °. The door is supported at the pivot point 2 using hinge brackets 4 attached to the front door 3. Said hinge bracket 4 has a vertically downward-cranked link lever 4' for the articulated mounting of the lower end of a push rod 5. At the upper end, the push rod 5 is also articulated to a height-adjustable slider 6. For this purpose, the slider 6 is guided with a precise fit in a vertical housing support rail 7 with a U-shaped cross-section. Furthermore, the above-mentioned slider 6 has a mounting bolt 8 at the top for the compensating compression spring.

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9, the preload of which can be adjusted using an upper counter bearing 10 and determines the door movement behavior. Fig. 1 also shows the front door 3 in the closed state according to position A. The sliding piece 6 assumes the height position A' in the housing support rail 7 and the pivotable pivot point of the link lever 4 ^r with its push rod 5 assumes the position A ¹ '.

Fig. 1a illustrates the partially shown front door 3 in intermediate opening position B. In position B, usually at half the opening angle (45 °), the compensating pressure spring 9 on the counter bearing is adjusted so that the front door 3 automatically remains in this position. The front door 3 is in a state of unstable equilibrium, i.e. a small actuating force is sufficient to move it into the closed position A or the open position C (Fig. 1b). In other words: the front door 3 falls from its position B by itself with the smallest of force, either force-fitting into its locking mechanism or gently into the hinge.

Note: According to Fig. 1b, the front door 3 is in position C, the fully open position. According to Fig. 1, the sliding piece 6 assumes the height position C under the simultaneous maximum spring pressure effect. (The highest possible point in the housing support rail 7) and the push rod pivot point in the link lever 4' has been pivoted to the height position C ^11. (Similarly, in door position B, the intermediate position, the link lever 4' assumes the height position B ^11. The intermediate position of the sliding piece 6 has not been drawn for the sake of clarity; it is located between C and A ¹ ); see also Fig. 4.

Fig. 2 shows the upper counter bearing 10 for the compensating pressure spring 9 in an enlarged view as a detail at "X" in Fig. 1. An internally threaded pressure plate 11 that can be moved up and down is inserted into the housing support rail 7. A threaded pin 12 that holds the compensating pressure spring 9 rotates in the internal thread of the pressure plate 11 with a bevel gear and track pin 14 molded onto the top. Said track pin 14 is mounted on the front side and is fixed in place. The bevel gear 13 of the threaded pin 12 is

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with a bevel gear 15 of the adjusting screw 16 in engagement, so that when the adjusting screw 16 is actuated, the angle drive 13, 15 causes the threaded pin 12 to rotate; the pressure plate 11 is moved up or down depending on the direction of adjustment and the compensating pressure spring 9 on the underside of the pressure plate is thus pre-tensioned more or less. The adjusting screw 16 is accessible from the front in a convenient working position when the front door 3 is open.

Fig. 3 shows a design of the door or pressure spring linkage that is significantly more cost-effective than that shown in Fig. 1. The modified sliding piece 6' is designed as an injection-molded part with a molded-on push rod 5 ¹ and spring retaining bolt 8 ^1. The push rod 5' and sliding piece 6' are pivotally connected via a thin film hinge 6''. The push rod 5 ¹ has a suspension opening at the lower end into which the nose 4 ¹¹¹ of a slightly modified linkage lever 4 ^M is snapped.

Fig. 4 shows a simulated movement sequence of the front door 3, the sliding piece 6 and the link lever 4 ^1. The center of gravity of the front door 3 is at point S. The vertical force component of the door weight acting on this is designated F, with the door weight being counteracted by the respective force of the compensating compression spring 9. Only in position B do the spring force and door weight component F _ß cancel each other out, i.e. F _ß becomes 0. The front door 3 remains in this position. After overcoming position B in the opening direction, the vertical force component F increases rapidly. This would cause the front door 3 to hit the hinge with inadmissible force and damage its bearings over a longer period of use. (Or, in the opposite direction, fall too forcefully into the locking lock). The resulting forces Fp to F. are now additionally counteracted by sliding friction forces which arise in the housing support rail 7. Depending on the angle of inclination, the push rod 5 presses the sliding piece 6 more or less firmly against the side wall of the U-profile of the housing support rail 7, thereby dampening the door movement and, as mentioned above, functioning as an integrated braking device. As indicated, the length of the lever arm b, the distance from the pivot point 2

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to the center of gravity of the door S and the length of the lever arm c, the distance from the pivot point 2 to the lower attachment point of the push rod 5 in the linkage lever 4' are dimensioned in such a way that relatively low spring forces are sufficient to realize the aforementioned functional sequence.

Fig. 5 illustrates a push rod driven front door 3, the weight of which is balanced by means of an adjustable tension spring 17. The sliding piece 18, which is also guided in the housing support rail 7, has a centrally formed pin 18' and a suspension bolt 19 arranged at the bottom. A height-adjustable suspension bracket 20 with an adjusting screw 21 is arranged in the machine base area of the housing support rail 7. The tension spring 17 is clamped between the suspension bolt 19 and the suspension bracket 20 (and in contrast to the design according to Fig. 1, is placed in the lower half of the housing support rail 7). The upper end of the door-linking push rod 22 is anchored or attached to the pin 18' of the spring-loaded slider 18 and its lower end is anchored or attached directly to the suspension point 23 of the front door 3. The hinge plate 24 serves exclusively to support the door in the pivot point 2. Sliding friction forces that dampen door movement in the housing support rail 7 are generated analogously to Fig. 1 or Fig. 4 by lateral push rod pressure on the slider 18. (In a manner not shown, the push rod 22 can also be articulated directly to the hinge plate 24, which is provided with various suspension points).

Fig. 6 shows a longitudinal section in an "enlarged view along the line a-a in Fig. 5. A section of the housing support rail 7 and the sliding piece 18 guided longitudinally therein together with the pin 18' are shown. As mentioned above, the push rod 22 is pivotally mounted on the pin 18' and secured in place by a disk 25.

According to Fig. 7, the front door 3 is hinged in a movement-damped manner by a gas spring 26 that is fixed in place in the housing support rail 7. The piston rod 27 of the gas spring 26 is attached in a hinged manner to the lowest end 28 of a straight door hinge plate 29 in a position-secured manner.

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In all examples shown, the front door 3 is always fitted on both sides with an adjustable compensating spring 9 or 17 or gas spring 26
Only a maximum of three different individual parts in duplicate are required. (Sliding piece, push rod,
hinge angle).

In a manner not shown, a spring adjustment can be made according to the
The embodiment according to Fig. 1 can be carried out on the upper counter bearing 10 with the aid of a horizontally movable wedge piece. When an adjusting screw is operated, the said wedge compresses the compensating spring more or less via a beveled bracket.

Also in a manner not shown, a double-sided friction brake can be attached directly to the door bearing points. One
Brake pad is held in place by two disc springs and a
Adjusting screw with nut pressed more or less tightly.

Claims (3)

EBHZ-91/59 .£5.01.1993 "ßa/ub Licenti a Patent-Verwaltungs-GmbH Frankfurt/Main Protection claims 1. Spring-loaded hinge for front doors of household dishwashers with pivotable angles and with adjustable compensating pressure springs arranged within vertical housing support rails, characterized by the following features, a) that the compensating pressure spring (9) is clamped between a sliding piece (6) movably guided in the upper half of the housing support rail (7) and an adjustable upper counter bearing (10), b) that the spring-loaded sliding piece (6) is connected to the upper end of a push rod (5) in an articulated and force-locking manner, c.) that the opposite lower end of the push rod (5) is connected in an articulated manner to a vertically downward cranked linkage lever (4 ¹ ) of the hinge bracket (4) of the front door (3), d) that the sliding piece (6 ¹ ) and the push rod (5 ¹ ) are designed as a one-piece injection-molded part and are elastically connected to one another by a molded film hinge (6 ¹¹ ). 2. Spring-loaded hinge for front doors of household dishwashers with adjustable compensating tension springs arranged within vertical housing support rails, characterized by the following features, a) that the compensating tension spring (17) is clamped between a suspension bolt (19) of a sliding piece (18) that is longitudinally movable in the lower half of the housing support rail (7) and a height-adjustable suspension bracket (20) arranged in the machine base area, EBHZ-91/59 .25.01.1993 üa/ub b) that a pin (18 ¹ ) is formed on the sliding piece (18), which is non-positively connected to the front door (3) via a hinged push rod (22) and with a suspension point (23). 3. Spring-loaded hinge for front doors of household dishwashers and with door weight balancing devices attached to vertical housing support rails, characterized in that a gas spring (26) with a movement-damped piston rod (27) can be used as the balancing device.