Dustproof and waterproof slewing bearing for crane

Abstract

The utility model discloses a dustproof and waterproof slewing bearing for a crane, which comprises an outer ring, an inner ring, an upper sealing element, a lower sealing element and a steel ball, and the outer ring and the inner ring are respectively provided with a semi-arc raceway for accommodating and mounting the steel ball; built-in frameworks are arranged in the upper sealing element and the lower sealing element, the upper sealing element and the lower sealing element are respectively provided with three arc lips, the outermost lip is a dustproof lip, and the inner two lips are oil-proof lips. According to the multi-arc lip sealing element with the built-in framework and the matched slewing bearing wedge-shaped inclined plane sealing structure, the oil discharge channels are uniformly distributed on the outer ring of the slewing bearing, so that the dustproof and waterproof sealing capabilities of the slewing bearing are greatly improved, and the service life of the slewing bearing is prolonged.

Description

Technical Field

[0001] The utility model relates to the field of slewing bearings, in particular to a dustproof and waterproof slewing bearing for cranes. Background Art

[0002] A slewing bearing is a rotating support component and is considered an extra-large bearing. It typically consists of an inner ring, outer ring, rollers, a spacer (cage), seals, plugs, and taper pins. The inner or outer ring typically has drive teeth that mesh with the drive pinion to transmit torque and power. Single-row ball slewing bearings use steel ball rollers in a single row, also known as single-row.

[0003] Slewing bearings are widely used in construction machinery, mining machinery, medical machinery, wind turbine machinery, and other machinery requiring relative rotational motion, such as cranes, excavators, wind turbines, and tunnel boring machines. Slewing bearings connect the upper and lower rotating bodies. However, slewing bearings are expensive and difficult to install and maintain. Therefore, a failure in these bearings poses significant safety risks and downtime risks, resulting in significant economic losses.

[0004] The general operating environment of construction machinery is poor, with much dust and impurities; the continuous operation time is sometimes long; customers have a weak awareness of machinery maintenance; the continuous operation reliability of construction machinery is high, and failure and downtime will cause serious losses to customers. Therefore, high requirements are placed on the reliability and durability of construction machinery, especially the reliability and durability of the slewing bearing, which is a key component. Among them, the seal of the slewing bearing is crucial to the reliability of the slewing bearing.

[0005] Existing slewing bearings, such as the utility model patent "A Waterproof Design Slewing Bearing," application number 2019210228506, and the utility model patent "A Slewing Bearing Sealing Structure," application number 2018205483026, have weak sealing capabilities and are essentially non-waterproof. Rainwater can enter the internal raceway of the slewing bearing, causing grease to leak out of the seal. This leads to grease loss, drying up the bearing and rusting the raceway. This in turn causes faults such as abnormal noise and vibration, severely reducing the bearing's fatigue performance and severely impacting the reliability of the entire machine. Furthermore, current crane slewing bearings lack dedicated oil drain channels. When relubricating, excess grease or waste oil drains from the sealing lip of the seal, causing it to warp. Iron filings and impurities in the waste oil further cause abnormal wear of the sealing lip, reducing the sealing capability of the seal, causing false oil leaks in the vehicle, and contributing to environmental pollution.

[0006] Therefore, it is necessary to develop a new type of dustproof and waterproof slewing bearing for cranes to overcome the above problems. Utility Model Content

[0007] Purpose of the utility model: In view of the shortcomings and defects of the existing technology, the utility model provides a dustproof and waterproof slewing bearing for cranes, which is provided with a multi-arc lip seal with a built-in skeleton and a matching slewing bearing wedge-shaped inclined surface sealing structure, and a uniformly distributed oil discharge channel is provided on the outer ring of the slewing bearing, which greatly improves the dustproof and waterproof sealing ability of the slewing bearing and increases the service life of the slewing bearing.

[0008] Technical Solution: This utility model provides a dustproof and waterproof slewing bearing for cranes, characterized by comprising an outer ring, an inner ring, an upper seal, a lower seal, and steel balls. Both the outer and inner rings are equipped with semicircular raceways for accommodating the steel balls. The upper and lower seals are each internally provided with a built-in framework. Each seal features three circular lips: the outermost one is a dustproof lip, and the inner two are oil-proof lips. These lips ensure reliable and sustained pressure, elasticity, and compression, preventing grease from leaking out during grease filling or use, and providing a durable waterproof and dustproof seal.

[0009] The outer ring gear of the outer ring has a circular oil drain port located between the teeth at the root, which is connected to the raceway inside the outer ring. When grease is added to the slewing bearing raceway, it is prevented from being discharged from the sealing lip and is discharged from the oil drain port between the outer teeth of the outer ring gear, thus ensuring sealing performance while achieving lubrication of the outer ring gear.

[0010] The arcuate lips of the upper and lower seals fit onto the mating surfaces of the outer and inner rings of the slewing bearing. The upper and lower seals are provided with wedge-shaped slopes on the outer and inner rings, respectively. Based on the slewing bearing raceway center, the position farther from the raceway center is considered low, while the position closer to the raceway center is considered high. This effectively isolates rainwater and car wash water.

[0011] Wherein, one end of the non-sealing lip of the upper sealing member and the lower sealing member is fixed on the outer wall of the inner ring and the inner wall of the outer ring respectively.

[0012] The outer ring upper surface and the inner ring lower surface are respectively provided with an outer ring wedge-shaped inclined surface and an inner ring wedge-shaped inclined surface at the fitting parts with the arc lip of the upper seal and the arc lip of the lower seal.

[0013] The outer ring wedge-shaped inclined surface and the inner ring wedge-shaped inclined surface are both based on the center of the slewing bearing raceway, with the lower position being farther away from the raceway center and the higher position being closer to the raceway center.

[0014] Beneficial Effects: Compared with existing technologies, this invention offers the following significant advantages: By providing a multi-lip seal with an internal skeleton, a matching wedge-shaped sloped surface slewing bearing sealing structure, and an oil drainage channel on the slewing bearing outer ring, this invention enhances the slewing bearing's dust and water sealing capabilities, thereby resolving slewing bearing failures such as abnormal noise and vibration caused by water ingress and grease loss. By providing an oil drainage channel between the outer teeth of the slewing bearing outer ring, the discharged grease lubricates the slewing bearing's outer ring gear, thereby extending the outer ring gear's service life. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a structural diagram of the utility model;

[0016] Figure 2 It is a schematic diagram of the cross-sectional structure of the utility model;

[0017] Figure 3 This is a schematic diagram of the installation structure of the utility model;

[0018] Figure 4 This is a schematic structural diagram of the upper sealing member of the present utility model;

[0019] In the figure, 1 is the outer ring; 11 is the outer ring gear; 12 is the oil drain port; 13 is the outer ring wedge-shaped inclined surface; 2 is the inner ring; 21 is the inner ring wedge-shaped inclined surface; 3 is the upper seal; 31 is the built-in skeleton; 32 is the arc lip; 4 is the lower seal; and 5 is the steel ball. DETAILED DESCRIPTION

[0020] The technical solution of the present utility model is further described below in conjunction with the accompanying drawings and specific implementation methods.

[0021] The dustproof and waterproof slewing bearing for cranes of this utility model comprises an outer ring 1, an inner ring 2, an upper seal 3, a lower seal 4, and steel balls 5. Both outer ring 1 and inner ring 2 are equipped with semicircular raceways and accommodate and fit the steel balls 5. Supported by the steel balls 5, the outer ring 1 and inner ring 2 are assembled into a single assembly, allowing them to rotate concentrically relative to each other. One end of the non-sealing lip of the upper seal 3 and the lower seal 4 is fixed to the outer wall of the inner ring 2 and the inner wall of the outer ring 1 respectively, and three arc lips 32 are provided to fit with the outer ring wedge bevel 32 on the upper surface of the outer ring 1 and the inner ring wedge bevel 21 on the lower surface of the inner ring 2 to achieve a sealing function, thereby preventing external water and impurities from entering the internal raceway of the slewing bearing and preventing the grease in the slewing bearing raceway from flowing out; an internal skeleton 31 is provided inside the upper seal 3 and the lower seal 4; the outer ring wedge bevel 13 and the inner ring wedge bevel 21 are provided at the fitting parts of the upper surface of the outer ring 1 and the lower surface of the inner ring 2 with the arc lip 32 of the upper seal 3 and the arc lip 32 of the lower seal 4 respectively; an oil drain port 12 is provided at the root of the outer ring gear 11.

[0022] The outer ring wedge-shaped slope 13 and the inner ring wedge-shaped slope 21 are both based on the center of the slewing bearing raceway, with the slope farther from the raceway center being lower and the slope closer to the raceway center being higher. This prevents rainwater and high-pressure water from washing cars from flowing into the slewing bearing raceway through the outer ring wedge-shaped slope 13 and the inner ring wedge-shaped slope 21.

[0023] The arc lip 32 provided on the upper seal 3 and the lower seal 4 is arc-shaped and has three lips, the outermost one is a dustproof lip, and the inner two are oil-proof lips; the arc lip 32 of the upper seal 3 fits with the outer ring wedge-shaped inclined surface 13 on the outer ring 1, and the arc lip 32 of the lower seal 4 fits with the inner ring wedge-shaped inclined surface 21 on the inner ring 2, thereby achieving a dustproof and waterproof sealing effect of the slewing bearing; the upper seal 3 and the lower seal 4 are provided with a built-in skeleton 31 to ensure that the arc lip 32 fits with the outer ring wedge-shaped inclined surface 13 and the inner ring wedge-shaped inclined surface 21 with reliable and lasting pressure, thereby avoiding irreversible deformation of the seal and having good support and sealing properties.

[0024] Oil drain port 12 is located at the root of two teeth on outer ring gear 11. It is circular and communicates with the raceway of outer ring 1. When grease is added to the raceway, excess or waste grease from the raceway is discharged through oil drain port 12 onto the surface of outer ring gear 11. This prevents excess grease from lifting the sealing lip and overflowing during grease addition, which would otherwise reduce sealing effectiveness. Excess grease can also lubricate outer ring gear 11. During slewing bearing operation, oil drain port 12 is blocked with a rubber plug to prevent excessive grease loss.

[0025] This utility model improves the dust and water-proof sealing capabilities of the slewing bearing by providing a multi-lip seal with an internal skeleton, a matching wedge-shaped sloped surface slewing bearing sealing structure, and an oil drainage channel on the slewing bearing outer ring. This solves slewing bearing failures such as abnormal noise and vibration caused by water ingress and grease loss. The oil drainage channel is provided between the outer teeth of the slewing bearing outer ring, and the discharged grease lubricates the outer ring gear of the slewing bearing, thereby extending the service life of the outer ring gear.

Claims

1. A dustproof and waterproof slewing bearing for a crane, characterized by: The invention comprises an outer ring (1), an inner ring (2), an upper seal (3), a lower seal (4) and a steel ball (5), wherein the outer ring (1) and the inner ring (2) are both provided with a semicircular arc raceway for accommodating and installing the steel ball (5); the upper seal (3) and the lower seal (4) are both provided with a built-in skeleton (31) inside, and the upper seal (3) and the lower seal (4) are both provided with three arc lips (32), wherein the outermost one is a dustproof lip and the inner two are oilproof lips.

2. The dustproof and waterproof slewing bearing for crane according to claim 1, characterized in that: A circular oil discharge port (12) is provided at the tooth root portion of the outer ring gear (11) of the outer ring (1), and the oil discharge port (12) is communicated with the raceway inside the outer ring (1).

3. The dustproof and waterproof slewing bearing for a crane according to claim 1, characterized in that: The arc lips (32) of the upper seal (3) and the lower seal (4) are fitted on the joint surfaces of the outer ring (1) and the inner ring (2) of the slewing bearing, and the upper seal (3) and the lower seal (4) are respectively provided with an outer ring wedge-shaped inclined surface (13) and an inner ring wedge-shaped inclined surface (21).

4. The dustproof and waterproof slewing bearing for a crane according to claim 3, characterized in that: One end of the non-sealing lip of the upper sealing member (3) and the lower sealing member (4) is fixed on the outer wall of the inner ring (2) and the inner wall of the outer ring (1), respectively.

5. The dustproof and waterproof slewing bearing for crane according to claim 3, characterized in that: The outer ring (1) upper surface and the inner ring (2) lower surface are respectively provided with an outer ring wedge-shaped inclined surface (13) and an inner ring wedge-shaped inclined surface (21) at the fitting parts with the arc lip (32) of the upper seal (3) and the arc lip (32) of the lower seal (4).

6. The dustproof and waterproof slewing bearing for crane according to claim 5, characterized in that: The outer ring wedge-shaped inclined surface (13) and the inner ring wedge-shaped inclined surface (21) are both based on the center of the slewing bearing raceway, with the lower position being farther away from the raceway center and the higher position being closer to the raceway center.

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