The present invention relates to a shelf height adjustment mechanism adapted to be used in refrigerators, enabling adjusting shelf heights inside a refrigerator body.

In refrigerators, food items and various containers are placed on shelves. Depending on the needs of the users, it may be required to modify the distance between two shelves, i.e. adjusting the height of a shelf in the body. In some refrigerators, a plurality of slots or rails are formed on two opposite walls of the body in order to adjust the height of a shelf. The user changes the height of a shelf by removing it from the slots of a certain elevation and placing it to another slot pair on a desired elevation. However, to that end, the user needs to first pull the shelf out of the body, and then to push the shelf back in after adjusting its height. This creates a problem for the users particularly with coolers whose doors cannot be completely opened. In addition, when the shelf is loaded, the user is obliged to remove the food products from the shelf to change the position thereof.

The patent application no. JP2004286411 (A) discloses a refrigerator in which the height of a shelf can be changed in certain limits by means of a threaded pulley mounted on the edge portion or the lower portion of the shelf and rotated by means of a belt.

The patent application no. KR20140097798 (A) discloses a shelf assembly enabling changing the height of shelves used in refrigerators.

The aim of the present invention is to realize a shelf height adjustment mechanism adapted to be used in refrigerators, enabling shelf heights to be stably changed by application of a reasonable force by a user, even when the shelf is extremely loaded.

The height adjustment mechanism realized to achieve the aim of the present invention, is used to adjust heights of body shelves used in refrigerators. The height adjustment mechanism of the invention comprises right hand threaded or left hand threaded shafts perpendicularly mounted on the corners of a rectangular prism shaped frame consisting of vertical and horizontal arms, and pulleys with threads cut in their hub bores are mounted on the threaded shafts. The height adjustment mechanism is further provided with a timing belt engaging the periphery of the pulleys. A user moves the timing belt by means of a handle, and the pulleys are thus rotated in clockwise or counter-clockwise direction. The pulleys which simultaneously rotate, move upwards or downwards on the threaded shafts. Thus, the shelf bearer fitted on the pulleys and therefore the shelf on the shelf bearer moves upwards or downwards by the user puling the timing belt rightwards or leftwards.

The height adjustment mechanism further comprises a direction adjustment lever provided on the handle, which can be brought by a user to a "shelf raising" position used to raise the shelf and a "shelf lowering" position used to lower the shelf depending on the (leftwards or rightwards) direction which the timing belt is moved, and a ratchet mechanism activated by said direction adjustment lever, enabling the timing belt to be advanced by being sequentially pulled in one direction by the handle being pulled in one direction and being pulled back in a free state, and the shelf to be raised or lowered to an extent desired by the user so as to remain in the frame.

The height adjustment mechanism realized to achieve the aims of the present invention is illustrated in the accompanying drawings, wherein:

Figure 1 is a frontal view of the height adjustment mechanism in a refrigerator.

Figure 2 is a perspective view of the height adjustment mechanism.

Figure 3 is an exploded view of the height adjustment mechanism.

Figure 4 is a perspective view of the height adjustment mechanism, from another angle. Figure 5 is an exploded view of a ratchet mechanism.

Figure 6 is a schematic view of the height adjustment mechanism utilizing right hand threaded shafts, while the shelf is being raised.

Figure 7 is a schematic view of the height adjustment mechanism in the state in which the handle is pulled back in a free state in order to raise the shelf again.

Figure 8 is a schematic view of the height adjustment mechanism utilizing right hand threaded shafts, while the shelf is being lowered.

Figure 9 is a schematic view of the height adjustment mechanism in the state in which the handle is pulled back in a free state in order to lower the shelf again.

The elements in the figures are numbered individually and the correspondence of these numbers are given hereinafter.

1. Height adjustment mechanism

2. Frame 3. Shelf bearer

4. Threaded shaft

5. Timing belt

6. Pulley

7. Handle

8. Direction adjustment lever

9. Ratchet mechanism

10. Ratchet wheel

11. Latch

12. Ratchet pulley

13. Housing

14. Cover

15. Nose piece

16. Push spring

17. Refrigerator

18. Shelf

Y : Shelf raising position

A: Shelf lowering position

The height adjustment mechanism (1) adapted to be used in refrigerators (17) having at least one shelf (18) on which food products are placed in the cooler/freezer compartments in a body, enabling adjusting the height of the shelf (18) in the body, comprises

- a rectangular prism shaped frame (2) consisting of vertical and horizontal arms,

- a shelf bearer (3) movable upwards/downwards inside the frame (2), on which is placed the shelf (18) whose height is desired to be adjusted,

- four threaded shafts (4) mounted on four comers of the frame (2), in perpendicular direction to the horizontal shelf bearer (3) plane, - four pulleys (6) with internal helical grooves cut in their hub bores or central bores, mounted on the threaded shafts (4), provided below the shelf bearer (3), performing simultaneously rotation motion and linear motion in upwards/downwards direction on the threaded shafts (4) by means of a timing belt (5) and enabling the shelf bearer (3) to be moved upwards/downwards, and

- a handle (7) connected to the timing belt (5), enabling the timing belt (5) to be moved in horizontal direction rightwards, i.e. in counter-clockwise direction or leftwards, i.e. in clockwise direction. The "right" and "left" directions are defined with respect to the users.

The height adjustment mechanism (1) of the invention comprises

- a direction adjustment lever (8) provided on the handle (7), which can be brought by a user to a shelf raising position (Y) used to raise the shelf bearer (3) and the shelf (18) and a shelf lowering position (A) used to lower the shelf bearer (3) and the shelf (18) depending on the (leftwards or rightwards) direction which the timing belt (5) is moved, and

- a ratchet mechanism (9) connected to the handle (7) and activated by said direction adjustment lever (8), enabling the timing belt (5) to be pulled in one direction (rightwards or leftwards) by the handle (7) locking on the timing belt (5) and the handle (7) to move in a free state on the timing belt (5) by disengaging the handle (7) from the timing belt (5) upon the handle (7) being moved in opposite direction, depending on the upwards or downwards movement direction adjusted by the direction adjustment lever (8), thereby enabling the timing belt (5) to be advanced by being sequentially pulled in one direction by the handle (7) being pulled in one direction and being pulled back in a free state, and the shelf (18) to be raised or lowered to an extent desired by the user, so as to remain in the frame (2).

When it is desired to adjust the shelf (18) height by moving it upwards or downwards depending on the dimensions of the items such as food products, containers, bottles and the like placed in the refrigerator (17), the user actuates the timing belt (5) by means of the handle (7) by pulling it rightwards or leftwards from front. The pulleys (6) to which the timing belt (5) transmits motion, perform rotation motion in counter-clockwise direction when the timing belt (5) is pulled rightwards, and in clockwise direction when the timing belt (5) is pulled leftwards. The pulleys (6) performing rotation motion move upwards or downwards on the threaded shafts (4) on which they are engaged from their hub bores, thereby enabling the shelf bearer (3) fitted on the pulleys (6) and therefore the shelf (18) to be moved upwards or downwards. The shelf (18) is raised or lowered depending on the advancement distance of the timing belt (5) by the user. Unlike the prior art, the shelf (18) is enabled to be raised or lowered to an extent desired by the user so as to remain within the frame (2), by the timing belt (5) being sequentially advanced a plurality of times by means of the ratchet mechanism

(9).

The ratchet mechanism (9) comprises

- a ratchet wheel (10),

- a latch (11) triggered by the direction adjustment lever (8), locking the ratchet wheel (10) in one direction (in clockwise or counter-clockwise direction) and allowing the ratchet wheel

(10) to rotate in opposite direction,

- a ratchet pulley (12) concentric with the ratchet wheel (10), rotating and being locked together with the ratchet wheel (10), and meshed with the timing belt (5),

- a housing (13) supporting the ratchet pulley (12),

- a cover (14) supporting the ratchet wheel (10),

- a nose piece (15) provided on the latch (11), and a push spring (16) abutting on the right or left portions of the latch (11) by passing over the nose piece (15) in the position to which the direction adjustment mechanism (8) is brought and enabling the latch (11) to lock the ratchet wheel (10) in one direction by pressing thereon.

The ratchet mechanism (9) enables the timing belt (5) to be pulled back at a free state by being pulled by means of the handle (7) in one direction determined by the direction adjustment lever (8), and the shelf (18) to be raised or lowered at a desired level to an extent allowed by the dimensions of the frame (2), by the timing belt (5) being sequentially advanced is said direction (rightwards or leftwards).

In an embodiment of the invention, the threaded shafts (4) are right hand threaded, and

- the pulleys (6) ascend on the threaded shafts (4) by rotating in counter-clockwise direction, upon the timing belt (5) being sequentially pulled rightwards and the handle (7) being pulled back (leftwards) in a free state each time, and the shelf bearer (3) on the pulleys (6) and therefore the shelf (18) move upwards to an extent depending on the rightwards advancement distance of the timing belt (5) when the direction adjustment lever (8) is in shelf raising position (Y); - the pulleys (6) descend on the threaded shafts (4) by rotating in clockwise direction, upon the timing belt (5) being sequentially pulled leftwards and the handle (7) being pulled back (rightwards) in a free state each time, and the shelf bearer (3) on the pulleys (6) and therefore the shelf (18) move downwards to an extent depending on the leftwards advancement distance of the timing belt (5), when the direction adjustment lever (8) is in shelf lowering position (A),;

In another embodiment of the invention, the threaded shafts (4) are left hand threaded, and

- the pulleys (6) descend on the threaded shafts (4) by rotating in counter-clockwise direction, upon the timing belt (5) being sequentially pulled rightwards, and the shelf bearer (3) on the pulleys (6) and therefore the shelf (18) move downwards to an extent depending on the rightwards advancement distance of the timing belt (5); and

- the pulleys (6) ascend on the threaded shafts (4) by rotating in clockwise direction, upon the timing belt (5) being sequentially pulled leftwards, and the shelf bearer (3) on the pulleys (6) and therefore the shelf (18) move upwards to an extent depending on the leftwards advancement distance of the timing belt (5).

For a height adjustment mechanism (1) utilizing right hand threaded shafts (4), the shelf raising method comprises the steps of:

- switching the direction adjustment lever (8) to the shelf raising position (Y),

- locking the ratchet wheel (10) and therefore the ratchet pulley (12) by the latch (11) of the ratchet mechanism (9) such that they cannot rotate rightwards (in clockwise direction) and freely rotate leftwards (in counter-clockwise direction),

- pulling the handle (7) rightwards and thereby pulling the ratchet pulley (12) and the timing belt (5) rightwards,

- rotating by the timing belt (5), the pulleys (6) leftwards (in counter-clockwise direction) about their axes,

- the pulleys (6) moving upwards on the right hand threaded shafts (4),

- the shelf bearer (3) arranged on the pulleys (6) and therefore the shelf (18) moving upwards, and

- halting the upwards displacement of the shelf (18) once the horizontal advancement distance of the handle (7) is completed, - pulling the handle (7) back (leftwards), if the elevated level of the shelf (18) is not sufficient, i.e. if it is desired to raise the shelf (18) some more,

- allowing by the ratchet mechanism (9), the ratchet pulley (12) to rotate in counter-clockwise direction and to move leftwards on the timing belt (5) during the handle (7) is being pulled back (leftwards),

- the timing belt (5), pulleys (6), shelf bearer (3) and therefore the shelf (18) resting stationary during the handle (7) is being pulled back (leftwards),

- pulling the handle (7) rightwards again, advancing the timing belt (5) rightwards in order to raise the shelf (18) some more, and raising the shelf (18) again depending on the advancement distance of the timing belt (5).

In the shelf lowering method for the height adjustment mechanism (1) utilizing right hand threaded shafts (4), the direction adjustment lever (8) is brought to the shelf lowering position (A), and the shelf (18) is lowered to an extent desired by the user so as to remain within the frame (2) by sequentially pulling the timing belt (5) leftwards.

In the height adjustment mechanism (1) of the invention, the timing belt (5) is enabled to be sequentially moved rightwards or leftwards by means of a ratchet mechanism (9) connected to the timing belt (5), enabling the shelf bearer (3) and the shelf (18) thereon to be moved upwards or downwards even when the shelf (18) is extremely loaded. The ratchet mechanism (9) enables the shelf (18) to be raised or lowered to a desired level to an extent allowed by the dimensions of the frame (2).