Lip-shaped sealing ring for rotating shaft of micro circulating electric pump of washing machine

Abstract

A lip-shaped sealing ring for a rotating shaft of a micro circulating electric pump of a washing machine comprises a rubber body, the rubber body comprises a plurality of sealing lips used for sealing, and grooves used for storing oil are formed among the sealing lips. The sealing lip located in the middle and / or the upper portion in the axial direction is a first sealing lip which is in the shape of an arc-shaped protruding lip, the inner diameter of the lip top of the first sealing lip is D1, the radial distance from the lip top of the first sealing lip to the adjacent groove is A1, D1 is designed to be phi 1.0-phi 4.0, and A1: D1 is 10%-30%. The sealing lip located at the axial lower end is a second sealing lip and obliquely extends from the body to the axial lower end and the radial inner side, the inner diameter of the lip top of the second sealing lip is D2, the radial distance from the lip top of the second sealing lip to the adjacent groove is A2, D2 is designed to be phi 1.0-phi 4.0, and A2: D2 = 10%-30%. According to the special design, tests prove that enough groove oil storage capacity and sealing interference can be achieved even if a tightening spring is not used, and demolding can be conducted smoothly in the manufacturing process.

Description

TECHNICAL FIELD

[0001] The utility model relates to a lip seal ring for rotating shaft, especially to a lip seal ring for rotating shaft of micro circulation electric pump of washing machine. BACKGROUND

[0002] At present, the ordinary circulation drainage pump in household appliances such as washing machine is a micro shield electric pump driven by permanent magnet synchronous motor, and the rotating shaft does not need waterproof sealing, in order to prevent foreign matter from penetrating, the rotating shaft is sealed by a lip seal ring, and a clamping spring does not need to be installed, but the micro circulation electric pump for water washing of the detergent box has low flow, is driven by a high-speed micro brushless DC motor, and the lip seal ring for the rotating shaft must maintain long-term good waterproof sealing performance, but due to the further reduction of the rotating shaft diameter to below 5mm, it is difficult to install the clamping spring in the limited position, in order to ensure that the lip seal ring and the shaft have sufficient interference and the oil storage groove has sufficient oil storage depth and avoids causing demolding difficulty, the design and manufacture of the lip seal ring are challenged.

[0003] Common knowledge and terms can refer to Machinery Industry Press 1982 edition 1 or 1997 edition 2 "Mechanical Engineering Handbook" and "Electrical Engineering Handbook", Machinery Industry Press 2014 edition 1 "Pump Theory and Technology", China Aerospace Press 2011 edition 1 "Modern Pump Theory and Technology", China Electric Power Press 2008 edition "Pump and Fan", Machinery Industry Press 2003 edition 1 "Hydraulic and Pneumatic Sealing and Leakage Prevention", 2009 edition 1 "Sealing Design Handbook", and national standards GB / T7021 "Centrifugal Pump Nomenclature", GB / T 33925.1 "Liquid Pump and Its Device General Terms, Definitions, Quantities, Characters and Units Part 1: Liquid Pump", Machinery Industry Standard JB / T5415 "Micro Centrifugal Electric Pump". UTILITY MODEL CONTENT

[0004] To solve the above technical problems, the utility model provides the following technical scheme:

[0005] A lip seal ring for rotating shaft of micro circulation electric pump of washing machine, comprising a rubber body, the body comprises a plurality of sealing lips for sealing and a groove formed between the sealing lips for storing oil;

[0006] Characterized in that:

[0007] The sealing lip located in the axial middle and / or upper part is a first sealing lip, which is an arc-shaped convex lip, the inner diameter of the lip top of the first sealing lip is D1, the radial distance from the lip top of the first sealing lip to the adjacent groove is A1, and D1 is designed as Φ1.0-Φ4.0, and A1:D1=10%-30%;

[0008] The sealing lip at the axial lower end is a second sealing lip, which extends obliquely towards the axial lower end and the radial inner side of the body, the inner diameter of the lip top of the second sealing lip is D2, the radial distance from the lip top of the second sealing lip to the adjacent groove is A2, D2 is designed as Φ1.0-Φ4.0, and A2:D2=10%-30%.

[0009] The special design is verified by experiments, and even if the snap spring is not used, sufficient oil storage and sealing interference can be achieved, and the manufacturing process can be smoothly demoulded.

[0010] One of the typical designs of the lip-shaped sealing ring is that the sealing lip at the axial middle and upper part is two first sealing lips, the second sealing lip at the axial lower end is one, and the grooves are two. Compared with the prior art with only one oil storage groove, two grooves store oil, are not easy to flow out, have long-lasting lubrication effect, and the sealing lip is wear-resistant and long-lasting.

[0011] The second typical design of the lip-shaped sealing ring is that A1:D1=17%-21% and A2:D2=17%-21%, the radial depth of the groove 8 is in the most reasonable range, demoulding is extremely easy, and the interference sealing is very stable and reliable.

[0012] Further, the lip-shaped sealing ring surrounds the rotating shaft for sealing, the second sealing lip is provided with a ring cylindrical surface surrounding the rotating shaft, the diameters of the two are equal, the transition fitting surface formed by the ring cylindrical surface and the rotating shaft has sufficient axial length and will not cause large-area interference friction, the effect of preventing leakage by the groove oil storage is good, long-term use can retain sufficient lubricating oil to avoid wear of the sealing lip, so that the sealing performance of the sealing lip is ensured for long-term use, and the ring cylindrical surface also has a good rigid reinforcing effect on the lip top of the second sealing lip and the pump shaft interference fit, so that the sealing effect of the lip top is enhanced.

[0013] Further, D1=Φ2.1, A1:D1=19%, D2=Φ2.1, and A2:D2=19%, the rotating shaft diameter d is Φ2.3, the lip-shaped sealing ring is smoothly formed and demoulded, and the comprehensive performance such as oil storage capacity, sealing interference and sealing durability is good. BRIEF DESCRIPTION OF DRAWINGS

[0014] Figure 1 is a three-dimensional schematic view of two orientations of the lip-shaped sealing ring of the embodiment of the utility model;

[0015] Figure 2 is Figure 1 a sectional view of the lip-shaped sealing ring;

[0016] Figure 3 is Figure 2 an enlarged schematic view of the A area in the middle;

[0017] Figure 4 is usedFigure 1 A cross-sectional schematic diagram of a miniature circulating electric pump for a washing machine with a lip-shaped seal.

[0018] Figure 5 yes Figure 4 A magnified view of region B in the middle.

[0019] Figure label:

[0020] 1. Miniature electric pump; 2. Rotary shaft; 3. Lip seal ring; 4. Body; 5. Skeleton; 6. First sealing lip; 7. Second sealing lip; 8. Groove; 9. Annular cylindrical surface. Detailed Implementation

[0021] To enable those skilled in the art to better understand the technical solutions of this utility model, the technical solutions in the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings.

[0022] The terms "center," "upper," "lower," "inner," and "outer" used in the text are based on Figure 2 The orientation or positional relationship shown in the figure is that the center line is the central axis of the lip seal, i.e., the center.

[0023] Example 1

[0024] like Figures 1-5As shown, the pump shaft, i.e. the rotating shaft 2, of the micro circulating electric pump for washing machine is designed as d = Φ2.3, the lip seal ring 3 of the utility model which embraces the pump shaft seal comprises the body 4 made of rubber and the rigid framework 5, the body 4 comprises three sealing lips for sealing, two recesses 8 for storing oil are formed between the sealing lips; the sealing lip located in the axial middle and upper end is the first sealing lip 6, the shape of which is arc convex lip, the inner diameter of the lip top is designed as D1, the radial distance from the lip top to the groove bottom of the adjacent recess 8 is designed as A1, D1 is designed as Φ2.1, A1:D1 = 19%, that is, the radial depth A1 of the recess 8 is 0.4, the arc convex lip not only has good rigidity of the lip bottom but also is beneficial to the mold core occupying the recess 8 to be taken out, so that the lip seal ring 3 can be smoothly demolded when the rubber is formed and manufactured; the sealing lip located in the axial lower end is the second sealing lip 7, in order to facilitate the mold core occupying the upper recess 8 to be smoothly taken out downwards, the shape of the second sealing lip 7 is not arc, the body 4 extends a ring cylindrical surface 9 in the axial lower end and the radial inner side direction for embracing the rotating shaft 2, the upper part of the ring cylindrical surface 2 protrudes the lip top of the second sealing lip 7, the inner diameter of the lip top is designed as D2, the radial distance from the lip top to the groove bottom of the adjacent recess 8 on the upper side is designed as A2, D2 is designed as Φ2.1, A2:D2 = 19%, that is, the radial depth A2 of the recess 8 is 0.4. In this way, D1 and D2 are both designed as Φ2.1, the shaft diameter of the rotating shaft 2 for sealing is designed as Φ2.3, the interference amount of the sealing lip is 0.1, the effective radial depth of the oil storage space of the recess 8 is designed as 0.3, the oil storage amount is sufficient, and the oil storage of the two recesses 8 is not easy to be lost, so that the lip seal ring 3 can be smoothly demolded when the rubber is formed and manufactured, the lip seal ring embraces the rotating shaft 2, and enough sealing interference amount and good sealing effect can be achieved. At the same time, the ring cylindrical surface 9 of the second sealing lip 7 embracing the rotating shaft 2 is designed as the diameters of the two are equal, the transition fitting surface of the ring cylindrical surface 9 and the rotating shaft 2 has enough axial length and will not cause large-area interference friction, so as to prevent the motor performance from being affected, the effect of the recess 8 storing oil to prevent leakage is good, enough lubricating oil can be reserved for long-term use to avoid the sealing lip from being worn, so as to ensure the sealing performance of the sealing lip for long-term use, and the ring cylindrical surface 9 also plays a good role in rigidly strengthening the lip top of the second sealing lip 7 and the rotating shaft 2, so as to strengthen the sealing effect of the lip top.

[0025] In other embodiments, the shape of the first sealing lip 6 located in the axial upper end can also not be designed as arc convex lip, but be designed as the second sealing lip 7 extending in the axial upper end and the radial inner side direction of the body 4, which can also achieve smooth demolding.

[0026] The ring cylinder 9 of the second sealing lip 7 matched with the rotating shaft 2 can also have different diameters, and a slight interference can have a good early sealing effect and a slightly poor long-term wear resistance, a slight gap can have a slightly poor oil storage leakage, but all can have a good sealing effect under the condition of ensuring smooth demolding. The ring cylinder 9 can also be designed as a convex surface, a concave surface or a special-shaped surface, and all can have a good sealing effect under the condition of ensuring smooth demolding.

[0027] In some other embodiments of the extended application, for the rotating shaft 2 with a shaft diameter of d = Φ1.2-Φ4.2, the inner diameter of the lip top of the first sealing lip 6 is designed as D1 = Φ1.0-Φ4.0, A1:D1 = 10%-30%, the inner diameter of the lip top of the second sealing lip 7 is designed as D2 = Φ1.0-Φ4.0, A2:D2 = 10%-30%, as long as the first sealing lip 6 located in the middle part of the axial direction is designed as an arc convex lip, smooth demolding and sufficient sealing interference can be realized. When A1:D1 = 17%-21% and A2:D2 = 17%-21%, the radial depth of the groove 8 is in the most reasonable range, demolding is extremely easy, and interference sealing is very stable and reliable.

[0028] Although the specific embodiments of the utility model have been shown and described, those skilled in the art can understand that various changes, modifications, replacements and additions can be made to the embodiments without departing from the principles and purposes of the utility model, and the scope of the utility model is defined by the claims and their equivalents.

Claims

1. A lip seal ring for the rotating shaft of a micro-circulation electric pump of a washing machine, comprising a rubber body (4) having a plurality of sealing lips for sealing and grooves (8) between the sealing lips for storing oil; characterized in that: the sealing lips located in the middle and / or upper axial part are first sealing lips (6) in the shape of arc convex lips, the inner diameter of the lip top of the first sealing lips (6) is D1, the radial distance from the lip top to the adjacent groove (8) is A1, and D1 = Φ1.0-Φ4.0 is designed, A1:D1 = 10%-30%; the sealing lip located in the lower axial end is a second sealing lip (7) extending obliquely towards the lower axial end and the inner radial side of the body (4), the inner diameter of the lip top of the second sealing lip (7) is D2, the radial distance from the lip top to the adjacent groove (8) is A2, and D2 = Φ1.0-Φ4.0 is designed, A2:D2 = 10%-30%.

2. The lip seal of claim 1 wherein: the sealing lips located in the middle and upper axial part are two first sealing lips (6), the second sealing lip (7) is one, and the grooves (8) are two.

3. The lip seal of claim 1 wherein: The lip seal ring surrounds the rotating shaft (2) for sealing, the second sealing lip (8) is provided with an annular cylindrical surface (9) surrounding the rotating shaft (2), and the diameter of the annular cylindrical surface (9) is equal to that of the rotating shaft (2).

4. The lip seal of claim 1 wherein: A1:D1 = 17%-21%; A2:D2 = 17%-21%.

5. The lip seal of claim 4 wherein: D1 = Φ2.1, A1:D1 = 19%; D2 = Φ2.1, A2:D2 = 19%. D1 = Φ2.1, A1:D1 = 19%; D2 = Φ2.1, A2:D2 = 19%.

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