Household appliance with adjustment mechanism for the door weight compensation device

Abstract

The present invention relates to a household appliance (1) such as a dishwasher or an oven, the front door (3) of which is opened by pulling from the top downwards, comprising an adjustment mechanism (5) that balances the weight of the door (3) so that while the door (3) is being opened it doesn't fall by its own weight or closed in a hard way. The adjustment mechanism (5) comprises a spring (9) that applies a tensile force on the door (3), that is pulled to be tensioned by the pulling cable (10) which is activated by an adjustment rod (6), an endless screw (7) and a gearwheel (8).

Claims

1. A household appliance (1) comprising a body (2), a door (3) providing access into the body (2) and moving about a horizontal axis, a hinge (4) that attaches the door (3) to the body (2), a spring (9) balancing a weight of the door (3) by applying a tensile force on the hinge (4), and further comprising an adjustment mechanism (5) comprising an adjustment rod (6) that is rotatable, a pulling cable (10) fixed to one end of the spring (9) and providing to pull to strain the spring (9), a spool (11) rotated around a fixed axis by actuating of the adjustment rod (6) and providing the pulling cable (10) to wind around the spool, a retainer (13) providing to fix one end of the pulling cable (10) to the spool (11) and rotatable around the spool such that the retainer and the one end of the pulling cable are moved together with the spool (11), and a fixing arrangement (16) providing the tension of the spring (9) not to change until readjustment is made.

2. The household appliance (1) as in claim 1, wherein the fixing arrangement (16) comprises an endless screw (7) rotated by the adjustment rod (6) and a gearwheel (8) rotated by the endless screw (7) providing to transfer a rotational movement from the adjustment rod (6) to the spool (11).

3. The household appliance (1) as in claim 2, wherein the adjustment mechanism (5) comprises the spool (11), coaxial with the gearwheel (8), and rotated around the fixed axis of the spool by the gearwheel (8).

4. The household appliance (1) as in claim 2 or 3, wherein the adjustment mechanism (5) comprises the retainer (13) that provides to attach the one end of the pulling cable (10) on a front surface of the gearwheel (8) next to the spool (11) allowing the spool to be moved together with the gearwheel (8).

5. The household appliance (1) as in claim 2 or 3, wherein the adjustment mechanism (5) further comprises a guide (14) that extends from an end portion of the retainer (13) to curve the pulling cable (10) that stays outside the retainer (13) when passing from the retainer (13) to the spool (11), and providing the spring (9) to continue being tensioned by the pulling cable (10) during this passage, wherein the guide (14) includes a lip having a curved portion.

6. The household appliance (1) as in claim 2, wherein the adjustment mechanism (5) comprises a gearbox (12) that provides housing the endless screw (7) and the gearwheel (8) and a hole (15) allowing the pulling cable (10) to enter through a fixed point.

7. The household appliance (1) as in claim 2 or 3 wherein the adjustment mechanism (5) comprising the gearwheel (8), the spool (11), a guide (14) and the retainer (13) is produced as a single piece from plastic material.

8. The household appliance (1) as in claim 4, wherein the adjustment mechanism (5) further comprises a guide (14) to curve the pulling cable (10) that stays outside the retainer (13) when passing from the retainer (13) to the spool (11), and providing the spring (9) to continue being tensioned by the pulling cable (10) during this passage.

9. The household appliance (1) as in claim 4, wherein the adjustment mechanism (5) comprising the gearwheel (8), the spool (11), a guide (14) and the retainer (13) is produced as a single piece from plastic material.

10. The household appliance (1) as in claim 5, wherein the adjustment mechanism (5) comprising the gearwheel (8), the spool (11), the guide (14) and the retainer (13) is produced as a single piece from plastic material.

11. The household appliance (1) as in claim 6, wherein the adjustment mechanism (5) comprising the gearwheel (8), the spool (11), a guide (14) and the retainer (13) is produced as a single piece from plastic material.

12. A household appliance (1) comprising body (2), a door (3) providing access into a body (2) and moving about a horizontal axis, a hinge (4) that attaches the door (3) to the body (2), a spring (9) balancing a weight of the door (3) by applying a tensile force on the hinge (4), and further comprising an adjustment mechanism (5) comprising an adjustment rod (6) that is rotatable, a pulling cable (10) having an end fixed to one end of the spring (9) and providing to pull to strain the spring (9), a spool (11), located inside a gearbox (12) having a hole (15) through which the pulling cable passes from the spring (9) to the spool (11), and wherein the spool (11) is rotated around a fixed axis by actuating the adjustment rod (6) and provides the pulling cable (10) to wind around the spool, without changing pulling direction of the pulling cable from the spring (9) to the hole (15), a retainer (13) that is rotatable around the spool providing to fix an opposite end of the pulling cable (10) to the spool (11) and to move the retainer and the opposite end of the pulling cable together with the spool (11), and a fixing arrangement (16) providing the tension of the spring (9) not to change until readjustment is made.

Description

(1) The household appliance realized in order to attain above mentioned aim of the present invention is shown in the attached figures, where:

(2) FIG. 1—is the schematic view of a household appliance.

(3) FIG. 2—is the schematic view of a door adjustment mechanism.

(4) FIG. 3—is the schematic view of a gear box.

(5) FIG. 4—is the perspective view of a door adjustment mechanism and a spring.

(6) FIG. 5—is the perspective view of a door adjustment mechanism and a spring before balancing adjustment is made.

(7) FIG. 6—is the perspective view of a door adjustment mechanism and a spring after balancing adjustment is made.

(8) Elements shown in figures are numbered as follows: 1. Household appliance 2. Body 3. Door 4. Hinge 5. Adjustment mechanism 6. Adjustment rod 7. Endless screw 8. Gearwheel 9. Spring 10. Pulling cable 11. Spool 12. Gear box 13. Retainer 14. Guide 15. Hole 16. Fixing arrangement

(9) The household appliance (1), preferably a dishwasher or an oven, comprises a body (2), a door (3) providing access into the body (2), preferably moving about a horizontal axis and opened by holding onto a handle, a hinge (4) that attaches the door (3) to the body (2), a spring (9) preferably of helicoil shape, balancing the weight of the door (3) by applying a tensile force on the hinge (4) and an adjustment mechanism (5) that adjusts the tension of the spring (9).

(10) The adjustment mechanism (5) comprises an adjustment rod (6) that can be rotated preferably from the exterior of the body (2) manually or with the help of a hand tool like a screwdriver, a pulling cable (10) fixed to one end of the spring (9) and providing to pull the spring (9) to strain it, a spool (11) rotated around a fixed axis by rotating the adjustment rod (6) and providing the pulling cable (10) to wind around it without changing its direction, a retainer (13) providing to fix the end of the pulling cable (10) that winds around the spool (11) and to move together with the spool (11), and a fixing arrangement (16) that avoids the pulling cable (10) to be unwound from the spool (11) by the tensile force of the spring (9) and hence providing the tensile adjustment of the spring (9) not to change until readjustment is made by the user or the maintenance service.

(11) During the tension adjustment, the direction of the spring (9), one end of which is attached to the pulling cable (10), stays fixed, only being stretched or compressed and does not move to the right or left within the body (2) since the pulling cable (10) to which one end of the spring (9) is attached, is wound around a fixed spool (11) that only rotates around its axis, without making a displacement movement e.g. to the left or right. Consequently an additional movement space within the body (2) doesn't need to be allocated for the spring (9) and the pulling cable (10) that only move up and down along the direction of their central axis.

(12) In the preferred embodiment of the present invention, the fixing arrangement (16) comprises an endless screw (7) rotated by the adjustment rod (6) providing the transfer of rotational movement from the adjustment rod (6) to the spool (11) and a gearwheel (8) rotated by the endless screw (7). The spool (11) being coaxial with the gearwheel (8) is rotated about its axis by the gearwheel (8). The spool (11) is preferably produced in one piece with the gearwheel (8) and extends out surrounding the center of the gearwheel (8).

(13) As the tension adjustment of the spring (9) is made, the endless screw (7) is rotated by the adjustment rod (6) and the gearwheel (8) is rotated by the endless screw (7), and as the pulling cable (10) is wound around the spool (11), the spring (9) is strained. The strained spring (9) applies a force on the spool (11) in the opposite direction of the winding and the spool (11) tries to rotate the gearwheel (8) by rotating in the opposite direction of the winding. Since the gears of the gearwheel (8) that try to rotate are meshed with the grooves of the endless screw (7), movement in the unwinding direction is stopped, and the endless screw and the gearwheel (8) avoid the pulling cable (10) to be unwound from the spool (11) by the tensile force of the spring (9) and hence provide the tension of the spring (9) to stay unchanged, without the need for an auxiliary element, until the user or the maintenance service makes a readjustment.

(14) In this embodiment, the adjustment mechanism (5) comprises gearbox (12) that provides housing of the endless screw (7) and the gearwheel, and a hole (15) allowing the pulling cable (10) to enter through a fixed point, a retainer (13) right next to the spool (11), fixed to the front surface of the gearwheel (8) preferably by way of plastic injection, that provides fixing of the end of the pulling cable (10) winding on the spool (11), and to move it together with the gearwheel (8) and the spool (11), a guide (14) that provides the part of the pulling cable (10) that stays outside the retainer (13) to pass from the retainer (13) to the spool (11) making a curvature during winding, providing the spring (9) to continue being tensioned by leaning on the pulling cable (10) during this passage.

(15) The guide (14) provides the part of the pulling cable (10) that stays outside the retainer (13) to pass to the spool (11) by a smooth turn and avoid the pulling cable (10) to erode the outer edges of the retainer (13) (FIG. 6).

(16) The pulling cable (10) is produced of cables having a high yield strength or bendable but not stretchable materials like wire or textile thread. The pulling cable (10) is fixed to the retainer (13) by plastic injection and a pulling cable (10)—retainer (13) attachment that is not effected by humidity is attained.

(17) In this embodiment, the gearwheel (8), the spool (11), the guide (14) and the retainer (13) are produced of plastic material as a single piece.

(18) When the weight of the door (3) is tried to be balanced by the adjustment mechanism (5), the adjustment rod (6) is rotated by a hand tool such as a screwdriver, the adjustment rod (6) rotates the endless screw (7), and the endless screw (7) rotates the gearwheel (8). In the case where the door (3) weight is too much, the adjustment rod (6) is rotated so that the spring (9) tension is increased, e.g. in a clockwise direction and the gearwheel (7) starts rotating about its axis. The spool (11) also rotates together with the gearwheel (8) about its axis. When the spool (11) rotates, the part of the pulling cable (10) that stays outside the retainer (13) starts winding around the spool (11) passing over the guide (14) (FIG. 6). As the pulling cable (10) winds around the spool (11), it provides the spring (9) to be strained by pulling the end of the spring (9) to which it is attached. The spring (9) with increased tension applies a bigger tensile force on the hinge (4) and the door (3) does not fall due to its own weight after being opened. If the spring (9) tension is more than required, the adjustment rod (6) is rotated in e.g. counterclockwise direction to decrease the tension of the spring (9).

(19) Since the pulling cable (10) moved by the adjustment mechanism (5), and the spring (9) which is attached to the pulling cable (10) move only in the direction of extension and contraction without being displaced, the pulling cable (10) and the spring (9) can function within the body (2) in a comparably narrower space than the conventional state-of-the-art household appliances (1) wherein the door (3) weight adjustments are made, hence economizing space.