WO2017005426A1

WO2017005426A1 - A washer comprising additive with low coefficient of friction

Info

Publication number: WO2017005426A1
Application number: PCT/EP2016/062532
Authority: WO
Inventors: Merve ZAKUT; Osman Gokhan Ersoy
Original assignee: Arcelik Anonim Sirketi
Priority date: 2015-07-06
Filing date: 2016-06-02
Publication date: 2017-01-12

Abstract

The present invention relates to a washer (1) having a sealing element (6) that comprises an additive with a low friction coefficient and thus is improved in terms of wear resistance. By means of the present invention, the washer (1) is enabled to operate in a more silent manner and the lifespan thereof is prolonged.

Description

A WASHER COMPRISING ADDITIVE WITH LOW COEFFICIENT OF FRICTION

The present invention relates to a washer whereof the mechanical features are improved.

The washer of the present invention is a dishwasher or a washing machine. In the said washers, a sealing element, for example a gasket or bellows, is used between the door and the washing chamber in order to provide leakproofing. The sealing element is generally produced from elastomeric materials like ethylene propylene diene monomer (EPDM) rubber. The sealing element, that is produced from easily-deformable EPDM material due to its low elasticity modulus, being worn out in course of time, causes decrease in sealing performance and noise during the operation of the washer.

In the state of the art Patent Application No. US5208293, a rubber composition having low friction and comprising thermoplastic fluororesin is disclosed.

The aim of the present invention is the realization of a washer that is enabled to operate in a more silent manner and having a sealing element whereof the wear resistance is increased.

In the washer realized in order to attain the aim of the present invention, explicated in the first claim and the respective claims thereof, the sealing element disposed between the washing chamber and the door comprises an additive which is a huntite-hydromagnesite mineral. The sealing element is produced from a material that is the mixture of EPDM and huntite-hydromagnesite mineral. By means of the flat structure of the huntite-hydromagnesite mineral, the mixture of EPDM and huntite-hydromagnesite has a smooth and uniform distribution in the sealing element, thus, the sealing element acquires a lubricant effect.

In an embodiment of the present invention, the sealing element is obtained by mixing 90 – 70% EPDM by weight and 10 – 30% huntite-hydromagnesite mineral by weight.

In an embodiment of the present invention, the washer is a dishwasher or a washing machine.

The washer realized in order to attain the aim of the present invention is illustrated in the attached figures, where:

Figure 1 – is the perspective view of a washer when the door is in the closed position.

Figure 2 – is the perspective view of a washer when the door is in the open position.

Figure 3 – is the detailed perspective view of the door of a washer and the sealing element thereon.

Figure 4 – is the view of detail A in Figure 3.

The elements illustrated in the figures are numbered as follows:

1 - Washer

2 - Body

3 – Washing chamber

4 - Loading port

5 - Door

6 – Sealing element

The washer (1) comprises a body (2), a washing chamber (3) wherein the washing process is performed, a loading port (4) through which the items to be washed are loaded into the washing chamber (3), a door (5) that covers the loading port (4) and a sealing element (6) disposed between the loading port (4) and the door (5).

The sealing element (6) of the present invention comprises huntite-hydromagnesite mineral and ethylene propylene diene monomer (EPDM). By means of the huntite-hydromagnesite mineral with low coefficient of friction, the sealing element (6) acquires a lubricant effect and thus the wear resistance of the sealing element (6) is increased.

Tests

In the method of the present invention, the antislip effectiveness of the mixtures of huntite-hydromagnesite mineral and ethylene propylene diene monomer (EPDM) at different ratios is measured by comparing the coefficients of friction. The measurement of the coefficient of friction is performed in compliance with the test standard BS ISO 15113:2005 ''Rubber-Determination of frictional properties''. The said standard describes a method suitable for measuring the coefficient of friction of a rubber against rubber or against any other specified surface. Two test surfaces are brought together under the normal measured load movement. The surfaces move by sliding over each other at a predetermined standard speed and the applied load movement is recorded. The ratio of the friction force to the normal applied force is the coefficient of friction at the time of the experiment. In particular, in order to simulate the ambient conditions, the experiment is repeated under the dry and detergent environment. The reference plate comprises only ethylene propylene diene monomer (EPDM). The test results showing the comparative friction coefficient values are given in Table A and the performance results in Table B.

Table A:

Table 1

Sample	Friction Coefficients
Sample	Dynamic Friction Coefficient (Dry environment)	Dynamic Friction Coefficient (Detergent environment)
Reference plate	0.83	0.26
150 phr (huntite-hydromagnesite mineral / EPDM)	0.20	0.16
100 phr (huntite-hydromagnesite mineral / EPDM)	0.21	0.17
75 phr (huntite-hydromagnesite mineral / EPDM)	0.45	0.22

The mechanical features of the material comprising huntite-hydromagnesite mineral at the stated ratios compared with the reference plate are given in the table below.

Table B:

Table 2

	Reference Plate	75 phr (huntite-hydromagnesite mineral / EPDM)	100 phr (huntite-hydromagnesite mineral / EPDM)	150 phr (huntite-hydromagnesite mineral / EPDM)
SPECIFIC WEIGHT, g/cm3	1.11	1.11	1.16	1.26
HARDNESS , Sh A -ISO 7619-1	41	39	41	46
TENSILE STRENGTH, N/mm2 - ISO 37	8.87	3.6	5.2	6.5
ELONGATION AT BREAK , % - ISO 37	555	245	301	427
TEAR STRENGTH - ISO 34-1B	24.6	16.6	20.7	21.8
ABRASION mm3 - ISO 4649-A	304.4	332	377	438
DEF. UNDER STRESS,% (3 days 100°) - ISO 815-1	55.8	54.4	58.5	60.5

In the tests conducted, the sealing element (6) with a mixture ratio of 100 phr showing optimum mechanical features comprises respectively antimicrobial additive material with the ratio of 1 %, 3 % by weight and EPDM material with the ratio of 99 % and 97 %.

In an embodiment of the present invention, the sealing element (6) comprises EPDM material with a ratio of 90 – 70 % and huntite-hydromagnesite mineral with the ratio of 10 – 30 % by weight. According to the results of the laboratory tests given in Table A and Table B, the optimum huntite-hydromagnesite mineral ratio is determined as 10%-30%.

In an embodiment of the present invention, the sealing element (6) is produced from thermoplastic elastomer (TPE) which is polystyrene / elastomer block copolymer material. TPE presents advantages in terms of recyclability and ease of production. The TPE material is polystyrene / elastomer copolymer (for ex. SEBS or SBS) or thermoplastic vulcanizate (EPDM/PP). The TPE material used in the sealing element (6) is a thermoplastic vulcanizate obtained from the mixture of EPDM and polypropylene (PP) and is in granule form.

In an embodiment of the present invention, the sealing element (6) is produced from thermoplastic elastomer (TPE) which is a thermoplastic vulcanizate (TPV) derived from EPDM and polypropylene (PP).

In an embodiment of the present invention, the washer (1) is a dishwasher and the sealing element (6) is the gasket between the loading port (4) and the door (5).

In another embodiment of the present invention, the washer (1) is a washing machine and the sealing element (6) is the bellows between the loading port (4) and the door (5).

In the huntite-hydromagnesite mineral additive of the present invention, the surface friction coefficient of the ethylene propylene diene monomer (EPDM) material is reduced and thus the sealing element (6) is prevented from wearing out in the course of time and the lifespan of the washer (1) is prolonged. Moreover, the noise level, that is triggered by the vibrations during the operation of the washer (1) and that cannot be efficiently prevented due to the wear on the sealing element (6), is reduced.

Claims

A washer (1) comprising a body (2), a washing chamber (3) wherein the washing process is performed, a loading port (4) through which the items to be washed are loaded into the washing chamber (3), a door (5) that covers the loading port (4) and a sealing element (6) disposed between the loading port (4) and the door (5), characterized by the sealing element (6) comprising huntite-hydromagnesite mineral and ethylene propylene diene monomer (EPDM) material.
A washer (10) as in Claim 1, characterized by the sealing element (6) comprising EPDM material with a ratio of 90 – 70 % and huntite-hydromagnesite mineral with the ratio of 10 – 30 % by weight.
A washer (1) as in Claim 1 or Claim 2, characterized by the sealing element (6) comprising thermoplastic elastomer (TPE) material which is polystyrene / elastomer block copolymer.
A washer (1) as in Claim 1 or 2, characterized by the sealing element (6) comprising thermoplastic elastomer (TPE) material which is a thermoplastic vulcanizate (TPV) derived from EPDM and polypropylene (PP).
A washer (1) as in any one of the above claims, which is a dishwasher.
A washer (1) as in any one of the Claims 1 to 4, which is a washing machine.