Double-sided sealed engine crankshaft oil seal

Abstract

This utility model relates to the field of engine oil seal technology, and more particularly to a double-sided sealed engine crankshaft oil seal, including a support frame and a sealing frame. One end face of the support frame is interference-fitted with the inner wall of the flywheel housing. The support frame is covered with a rubber body. A sealing lip one on the engine side and a sealing lip two on the gearbox side are provided at the end of the rubber body away from the flywheel housing. Sealing lip one and sealing lip two are in interference contact with the sealing frame. The inner side of the sealing frame is interference-fitted with the crankshaft. The sealing frame is located between the two lips of the oil seal and the crankshaft, reducing the machining requirements of the crankshaft. The sealing frame is located between the sealing lip and the oil cavity, reducing the impact of oil on the sealing lip and preventing impurities in the oil from entering the sealing lip. The sealing lip uses a rubber lip with a spiral line, and the interference between the sealing lip and the sealing frame is small, which not only improves the oil seal's resistance to carbon buildup but also prevents vacuum formation between the two lips of the oil seal.

Description

Technical Field

[0001] This utility model relates to the field of engine oil seal technology, and in particular to a double-sided sealed engine crankshaft oil seal. Background Technology

[0002] With the increasing prevalence of engineering vehicles with hydraulic transmissions housed within the flywheel housing at the rear of the engine, there is a growing demand for oil seals that seal both engine oil on one side and transmission oil on the other. To meet this dual-sided sealing requirement, existing double-sided oil seals employ either a two-way mounting system or a single oil seal with two opposing spring-rubber lips that are interference-fitted with the crankshaft to achieve a seal on both sides. However, current double-sided radial spring-lip oil seals, where both lips are interference-fitted with the crankshaft, are prone to vacuum formation during operation, leading to a reduced seal life. Furthermore, the fit between the seal lips and the crankshaft places high demands on crankshaft machining. The spring-rubber lips also result in poor resistance to lateral movement. Additionally, the high clamping force of the sealing lips leads to significant carbon buildup as mileage increases. Utility Model Content

[0003] Technical objective: In order to overcome the shortcomings of the existing technology, this utility model provides a double-sided sealed engine crankshaft oil seal to prevent two different lubricating oils from mixing, achieve double-sided sealing, reduce crankshaft processing requirements, avoid vacuuming of the oil seal, and improve the oil seal life.

[0004] Technical Solution: To achieve the above objectives, this utility model discloses a double-sided sealed engine crankshaft oil seal, disposed between the crankshaft and the flywheel housing, including a support frame and a sealing frame. One end face of the support frame is interference-fitted with the inner wall of the flywheel housing. The support frame is covered with a rubber body. The end of the rubber body away from the flywheel housing is provided with a sealing lip one on the engine side and a sealing lip two on the gearbox side. The sealing lip one and sealing lip two are in interference contact with the sealing frame. The inner side of the sealing frame is interference-fitted with the crankshaft.

[0005] Furthermore, the sealing skeleton includes a sealing skeleton one on the engine side and a sealing skeleton two on the transmission side. The inner side of the sealing skeleton one is interference-fitted to the crankshaft, and the sealing skeleton two is interference-fitted to the outer side of the sealing skeleton one. The sealing lip one is in interference contact with the sealing skeleton one, and the sealing lip two is in interference contact with the sealing skeleton two.

[0006] Furthermore, the end of the second sealing skeleton away from the first sealing skeleton is provided with an axial flange, and the second sealing lip is in interference contact with the inner side of the flange.

[0007] Furthermore, the sealing lip adopts an end-face sealing structure.

[0008] Furthermore, both the sealing lip one and the sealing lip two have spiral lines on their openings.

[0009] Furthermore, both the first and second sealing lips are made of FKM peroxide.

[0010] Furthermore, the first sealing lip is made of FKM peroxide, and the second sealing lip is made of PTFE.

[0011] Compared with the prior art, the beneficial effects of this utility model are:

[0012] This invention relates to an engine crankshaft oil seal. A sealing skeleton is provided between the two lips of the oil seal and the crankshaft. The lips and the sealing skeleton are in direct contact, reducing the machining requirements on the crankshaft. The sealing skeleton is located between the sealing lip and the oil cavity, reducing the impact of oil on the sealing lip and preventing impurities in the oil from entering the sealing lip. The sealing lip uses a helical rubber lip, and the interference fit between the sealing lip and the sealing skeleton is small, which not only improves the oil seal's resistance to carbon buildup but also prevents vacuum formation between the two lips. The sealing lip uses FKM peroxide, which reduces the oil seal's rotational torque and increases its lifespan. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the overall structure of the double-sided sealed engine crankshaft oil seal in Example 2.

[0014] In the diagram, 1. Crankshaft; 2. Flywheel housing; 3. Support frame; 4. Sealing lip one; 5. Sealing lip two; 6. Sealing frame one; 7. Sealing frame two; 8. Flanged edge. Detailed Implementation

[0015] The following is in conjunction with the appendix Figure 1 The principles and features of this utility model are described, and the examples given are only used to explain this utility model and are not intended to limit the scope of this utility model.

[0016] A double-sided sealed engine crankshaft oil seal is disposed between the crankshaft 1 and the flywheel housing 2. It includes a support frame 3 and a sealing frame. One end face of the support frame 3 is interference-fitted with the inner wall of the flywheel housing 2. The support frame 3 is covered with a rubber body, one end of which is also interference-fitted with the inner wall of the flywheel housing 2. Two sealing lips are provided at the end of the rubber body away from the flywheel housing 2, namely a sealing lip 4 on the engine side and a sealing lip 5 on the gearbox side. The sealing lip 4 and the sealing lip 5 are in interference contact with the sealing frame. The inner side of the sealing frame is interference-fitted with the crankshaft 1.

[0017] Example 1

[0018] In this embodiment, the sealing skeleton is a single skeleton, with its inner side interference-fitted to the crankshaft 1, and sealing lips 4 and 5 interference-fitted to the outer side of the sealing skeleton. Sealing lip 4 is made of FKM peroxide, and sealing lip 5 is made of PTFE.

[0019] Example 2

[0020] In this embodiment, the sealing skeleton is a composite skeleton, including a sealing skeleton 6 on the engine side and a sealing skeleton 7 on the transmission side. Since the engine side has a larger oil volume and the transmission side has a smaller oil volume, to prevent oil from the engine side from flowing to the transmission side through the seam between the sealing skeleton 6 and the sealing skeleton 7, in this embodiment, the inner side of the sealing skeleton 6 is interference-fitted to the crankshaft 1, and the sealing skeleton 7 is interference-fitted to the outer side of the sealing skeleton 6. This design ensures a seamless connection on the engine side. The sealing lip 4 is in interference contact with the sealing skeleton 6, and the lip of the sealing lip 4 adopts an end-face sealing structure. The sealing lip 5 is in interference contact with the sealing skeleton 7, and there is a small interference fit between the sealing lip and the sealing skeleton. In this embodiment, both the sealing lip 4 and the sealing lip 5 are made of FKM peroxide. Specifically, the end of the sealing skeleton 7 away from the sealing skeleton 6 is provided with a flange 8 along the oil seal axis, and the inner side of the sealing lip 5 is in interference contact with the flange 8. Both sealing lip 4 and sealing lip 5 have spiral lines on their edges, ensuring that the space between the two lips is not absolutely sealed to the spaces on the engine side and the gearbox side, respectively, thus preventing a vacuum from forming between the two lips of the oil seal. For example, when crankshaft 1 stops working, outside air can slowly enter the space between the two lips through the spiral lines, restoring the balance of internal and external air pressure. When the oil seal operates to its limit, the interference fit between sealing lip 5 and the inner side of flange 8 becomes zero, at which point air enters the space between the two lips from the gearbox side, restoring the balance of internal and external air pressure.

[0021] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A double-sided sealed engine crankshaft oil seal, disposed between the crankshaft (1) and the flywheel housing (2), characterized in that, The system includes a support frame (3) and a sealing frame. One end face of the support frame (3) is press-fitted with the inner wall of the flywheel housing (2). The support frame (3) is covered with a rubber body. The end of the rubber body away from the flywheel housing (2) is provided with a sealing lip 1 (4) on the engine side and a sealing lip 2 (5) on the gearbox side. The sealing lip 1 (4) and the sealing lip 2 (5) are press-fitted with the sealing frame. The inner side of the sealing frame is press-fitted with the crankshaft (1).

2. The double-sided sealed engine crankshaft oil seal according to claim 1, characterized in that, The sealing skeleton includes a sealing skeleton one (6) on the engine side and a sealing skeleton two (7) on the gearbox side. The inner side of the sealing skeleton one (6) is interference-fitted to the crankshaft (1), and the sealing skeleton two (7) is interference-fitted to the outer side of the sealing skeleton one (6). The sealing lip one (4) is interference-fitted to the sealing skeleton one (6), and the sealing lip two (5) is interference-fitted to the sealing skeleton two (7).

3. The double-sided sealed engine crankshaft oil seal according to claim 2, characterized in that, The sealing skeleton 2 (7) is provided with an axial flange (8) at one end away from the sealing skeleton 1 (6), and the sealing lip 2 (5) is in interference contact with the inner side of the flange (8).

4. The double-sided sealed engine crankshaft oil seal according to claim 2, characterized in that, The sealing lip (4) adopts an end face sealing structure.

5. The double-sided sealed engine crankshaft oil seal according to claim 2, characterized in that, Both the sealing lip one (4) and the sealing lip two (5) have spiral lines on their openings.

6. The double-sided sealed engine crankshaft oil seal according to claim 2, characterized in that, Both the sealing lip one (4) and the sealing lip two (5) are made of FKM peroxide.

7. The double-sided sealed engine crankshaft oil seal according to claim 1, characterized in that, The first sealing lip (4) is made of FKM peroxide, and the second sealing lip (5) is made of PTFE.

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