WO2008052980A1

WO2008052980A1 - A washing machine

Info

Publication number: WO2008052980A1
Application number: PCT/EP2007/061650
Authority: WO
Inventors: Yavuz Sahin; Mehmet Kaya; Murat Elgun; Deniz Seker
Original assignee: Arcelik Anonim Sirketi
Priority date: 2006-10-31
Filing date: 2007-10-30
Publication date: 2008-05-08

Abstract

The present invention relates to a washing machine (1) wherein the inner surface of the air trap (4) is coated with hydrophobic material (A) in order to measure the water level received into the tub (3) accurately.

Description

Description A WASHING MACHINE

[0001] The present invention relates to a washing machine wherein the water level measurement is made accurately.

[0002] In washing machines, the amount of water received into the tub is determined by measuring the pressure of the air compressed in the air trap connected to the tub as the manometric height of the water level rises in the tub and comparing this pressure with the reference pressure value when the tub is empty.

[0003] However, the water that enters into the air trap during measurement cannot be entirely discharged after washing.

[0004] Moreover, when the machine is not used, the water left in the discharge conduit from the previous use can enter into the air trap for reasons such as vibration during the transportation of the machine, condensation under high temperatures etc. and slay there. This can lead to misreading of the reference pressure value to be used for comparison. Respectively, the level of water received into the machine cannot be determined accurately and less/more than the required amount of detergent and energy is used thus reducing the washing effectiveness. Various implementations relating to improvements in particularly the air trap design are devised in the technique in order to avoid the mentioned problems.

[0005] In the United States of America Patent Document No US5964001 , an air dome comprised of an angled tube is described in order to prevent water entering into the air dome and to be trapped therein when the washing machine is tilted.

[0006] In the Japanese Patent Document No JP7124382, an air trap design is described wherein the water inlet pipe is situated lower than the inner wall of the drain pipe in order to prevent the faulty measurement of the water level in the washing machine as a result of the air pool between the drain pipe and the air trap during water intake.

[0007] However, since only structural improvements are accomplished in state of the art implementations, the water left in the drain conduit from the previous use entering the air trap by evaporating and to be compressed therein cannot be prevented particularly when the machine is not used. Consequently, the determined reference pressure value is measured erroneously and the change in the pressure amount that is detected by comparing with this value and thus the water amount values present in the tub will be inaccurate.

[0008] The object of the present invention is to design a washing machine wherein the water level is measured with a great accuracy.

[0009] The washing machine designed to fulfill the objective of the present invention is explicated in the claims.

[0010] In the washing machine of the present invention, the inner surface of the air trap is partially or entirely coated by a hydrophobic material in order to prevent the adverse effect on the pressure and respectively the water level measurement of the water entering the air trap during measurement and not being completely discharged after washing or the water left in the drain conduit from the previous use entering the air trap as a result of vibration during transporting the machine from one place to another or condensation at high temperatures etc. when the machine is not used. The water repelling property of the hydrophobic material makes the unwanted water entering the air trap harder to cling to the inner surface of the air trap. Moreover, the water taken into the air trap during the washing process can be discharged more effectively.

[0011] In the preferred embodiment of the washing machine of the present invention, the air trap is connected to the tub and comprises a chamber wherein water fills and the air contained therein is compressed as water is received into the tub and a pipe with one end connected to the chamber, the other end to the pressure sensor, providing the communication therebetween. As water is received into the tub for performing the washing process, water also fills into the chamber. This in turn results in the air present in the chamber to proceed to the pipe by being compressed and to exert an extra pressure on the pressure sensor connected to the pipe. In the alternatives of this embodiment of the present invention, only the chamber, only the pipe or both can be coated with the hydrophobic material.

[0012] In other embodiments of the washing machine of the present invention, the inner surface of the air trap is partially or entirely coated with hydrophobic material depending on the geometric configuration of the air trap.

[0013] The washing machine designed to fulfill the objective of the present invention is illustrated in the attached figures, where:

[0014] Hgure 1 - is the front schematic view of an embodiment of the present invention.

[0015] Hgure 2 - is the schematic view of the air trap used in an embodiment of the present invention.

[0016] The elements illustrated in the figures are numbered as follows:

1. Washing machine

2. Drum

3. Tub 4. Air trap

5. Pressure sensor

6. Drain pipe

7. Chamber

8. Pipe

[0017] The washing machine (1) comprises a drum (2) wherein laundry is emplaced, a tub

(3) inside which the drum (2) rotates, an air trap (4) for measuring the water level as the air therein is compressed while the amount of water received into the tub (3) increases and a pressure sensor (5) connected to the air trap (4) that measures the pressure of the air compressed in the air trap (4) (Rgure 1).

[0018] The inner surface of the air trap (4) is at least partially coated with a hydrophobic material (A) that repels water thus reducing the amount of water clinging to the inner surface thereof.

[0019] The washing machine (1) furthermore comprises a drain pipe (6) for discharging out the waste water.

[0020] In the washing machine of the present invention, the air trap (4) comprises a chamber (7) connected to the tub (3) wherein water fills in as water is received into the tub (3) and the air contained therein is compressed and a pipe (8) with one end connected to the chamber (7), the other end to the pressure sensor (5), providing the communication therebetween (Rgure T).

[0021] In this embodiment, when the tub (3) is empty, the chamber (7) and the pipe (8) are filled with air and the pressure sensor (5) measures a reference value. During utilization as the water level rises in the tub (3), water also fills into the chamber (7). The water rising in the chamber (7) compresses the air in the pipe (8). The compressed air exerts an extra pressure on the pressure sensor (5) connected to the pipe (8) and there is an increase in the measured pressure value. The water amount is determined according to the magnitude of the difference between the measured pressure value and the reference value.

[0022] In the washing machine (1) of the present invention, the inner surface of the air trap

(4) is coated with a hydrophobic material (A). Thus, in case the water present in the drain pipe (6) enters the air trap (4) during conditions such as the transport of the washing machine (1), clinging of the water on the inner surface of the air trap (4) will be difficult and will flow out of the air trap (4) because of the water repelling property of the hydrophobic material (A).

[0023] In various embodiments of the washing machine (1) of the present invention, hy- drophobic coating (A) is applied on some portion or the entirety of the air trap (4) inner surface depending on the geometric configuration of the air trap (4). With the washing machine (1) of the present invention, the water level received into the tub (3) is measured accurately and the activities such as determining the load amount, dispensing of detergent etc. that depend on this data can be performed more precisely thus increasing the washing performance. Moreover, intake of extra water into the washing machine (1) and respectively the increase in energy consumption are prevented.

Claims

[0001] A washing machine (1) comprising a drum (2) wherein laundry is emplaced, a tub (3) inside which the drum (2) rotates, an air trap (4) for measuring the water level as the air therein is compressed while the amount of water received into the tub (3) increases and a pressure sensor (5) connected to the air trap (4) that measures the pressure of the air compressed in the air trap (4) and characterized by an air trap (4) wherein the inner surface is at least partially coated with a hydrophobic material (A) that repels water thus reducing the amount of water clinging to the inner surface of the air trap (4).

[0002] A washing machine (1) as in Claim 1, characterized by the air trap (4) comprising a chamber (7) connected to the tub (3) wherein water fills in as water is received into the tub (3) and the air contained therein is compressed and a pipe (8) with one end connected to the chamber (7), the other end to the pressure sensor (5), providing the communication therebetween.

[0003] A washing machine (1) as in Claim 2, characterized by the air trap (4) wherein only the inner surface of the chamber (7) is coated with hydrophobic material (A).

[0004] A washing machine (1) as in Claim 2, characterized by the air trap (4) wherein only the inner surface of the pipe (8) is coated with hydrophobic material (A).

[0005] A washing machine (1) as in Claim 1 or 2, characterized by the air trap (4) wherein the entire inner surface of the air trap (4) is coated with hydrophobic material (A).