Rapid grease injection device for crossed roller bearing without oil injection hole

Abstract

The utility model discloses a quick grease injection device for a crossed roller bearing without an oil injection hole, which relates to the technical field of bearing grease injection and comprises a grease injection device with an integrated structure, a grease injection part is arranged at the bottom of the grease injection device, a fitting part with the diameter smaller than that of the grease injection part is coaxially arranged at the bottom of the grease injection part, and the periphery of the fitting part is tightly attached to the inner wall of the bearing; the end face of the grease injection part is provided with an annular protrusion, and the annular protrusion extends into a bearing raceway to be subjected to grease injection and is tightly attached to the bearing raceway. A grease injection channel is formed in the grease injection part and comprises an axial hole penetrating through the annular protrusion and a radial hole communicated with the axial hole, and the radial hole is used for being connected with a grease injection gun. According to the utility model, through precise annular bulge sealing and optimized grease channel design, the industrial pain point that the crossed roller bearing without the oil injection hole is difficult to lubricate effectively is ingeniously solved, the direct, accurate and leakage-free injection of lubricating grease into a bearing raceway area is realized, and the operation is simple, convenient and quick.

Description

Technical Field

[0001] This utility model relates to the field of bearing grease injection technology, and in particular to a quick grease injection device for crossed roller bearings without grease injection holes. Background Technology

[0002] Because crossed roller bearings can simultaneously withstand radial, axial, and combined loads, they are suitable for complex stress scenarios and are therefore widely used in industrial robot joints and humanoid robots. With the optimization of crossed roller bearing structures, radial oil injection holes have begun to be eliminated. This closed design prevents external dust and contaminants from entering the bearing, thereby improving bearing life and efficiency. Simultaneously, it effectively slows grease loss during operation, extending the bearing's service life and reducing equipment maintenance costs. However, as crossed roller bearing technology matures, the elimination of oil injection holes has resulted in a lack of quick grease injection methods. Grease injection can only be performed through the gap between the inner and outer rings. This method is not only slow, but most of the grease is also trapped in the stepped grooves of the inner and outer rings, significantly impacting the convenience of grease injection. Therefore, a rapid grease injection device is urgently needed to improve the grease injection efficiency of crossed roller bearings without oil injection holes. Utility Model Content

[0003] The technical problem to be solved by this utility model is to provide a quick grease injection device for cross roller bearings without oil injection holes, which can effectively solve the grease injection problem of finished cross roller bearings and improve grease injection efficiency.

[0004] To achieve the above objectives, the technical solution adopted by this utility model is as follows:

[0005] A quick grease injection device for crossed roller bearings without grease injection holes includes an integral grease injection device. The bottom of the grease injection device has a grease injection section, and the bottom of the grease injection section has a fitting section with a diameter smaller than the grease injection section. The outer periphery of the fitting section is in close contact with the inner wall of the bearing. The end face of the grease injection section has an annular protrusion that extends into the bearing raceway to be greased and fits tightly with the bearing raceway. The grease injection section has a grease injection channel inside, which includes an axial hole penetrating the annular protrusion and a radial hole communicating with the axial hole. The radial hole is used to connect a grease injection gun.

[0006] Furthermore, the outer diameter of the grease injection portion is equal to the outer diameter of the bearing.

[0007] Furthermore, the clearance between the annular protrusion and the bearing raceway does not exceed 0.05 mm.

[0008] Furthermore, the length of the annular protrusion extending into the bearing raceway is equal to the width of the gap between the inner and outer rings of the bearing.

[0009] Furthermore, the diameter of the axial hole is 0.5 mm.

[0010] Furthermore, the diameter of the radial hole is 2 mm, and its axis is perpendicular to the axial hole.

[0011] Furthermore, the radial hole is a stepped hole that decreases in size from the outside to the inside.

[0012] Furthermore, the grease injection device is entirely made of steel.

[0013] Based on the above technical solution, the beneficial effects of this utility model are:

[0014] This invention cleverly solves the industry pain point of ineffective lubrication of crossed roller bearings without oil injection holes through an integrated structure, a precise annular raised seal, and an optimized grease channel design. It enables direct, precise, and leak-free injection of grease into the bearing raceway area, making operation simple and quick. At the same time, the structure is robust and durable, significantly improving the maintenance efficiency and effectiveness of such bearings and reducing long-term maintenance costs. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the structure of this utility model;

[0016] Figure 2 This is a schematic diagram of the present invention used in conjunction with a bearing.

[0017] The markings in the diagram are: 1. Grease injection device, 11. Grease injection part, 12. Fitting part, 13. Annular protrusion, 21. Radial hole, 22. Axial hole, 3. Bearing, 31. Bearing raceway. Detailed Implementation

[0018] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0019] The structures, proportions, sizes, etc., shown in the accompanying drawings of this specification are only for the purpose of assisting those skilled in the art in understanding and reading the content disclosed in the specification, and are not intended to limit the implementation conditions of this utility model. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportions, or adjustments to the size, without affecting the effects and purposes that this utility model can produce, should still fall within the scope of the technical content disclosed in this utility model.

[0020] It should also be noted that, unless otherwise stated, the terms "upper," "lower," "left," "right," "front end," and "rear end," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used solely for the convenience of describing this utility model and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. Changes or adjustments to these relative relationships, without substantially altering the technical content, should also be considered within the scope of implementation of this utility model.

[0021] like Figure 1-2 As shown, a quick grease injection device for crossed roller bearings without grease injection holes includes a one-piece grease injection device 1 made of steel. The bottom of the grease injection device 1 has a grease injection section 11, and a fitting section 12 with a diameter smaller than the grease injection section 11 is coaxially located at the bottom of the grease injection section 11. The outer periphery of the fitting section 12 is in close contact with the inner wall of the bearing 3, forming a seal between the grease injection device 1 and the inner ring of the bearing 3, preventing grease from leaking along the surface of the bearing inner ring or contaminating other non-target areas of the bearing. The outer diameter of the grease injection section 11 is equal to the outer diameter of the bearing 3. The one-piece structure of the grease injection device 1 is simple and robust, with no moving parts or easily damaged connecting parts, making it convenient to use, highly reliable, and not easily damaged.

[0022] The end face of the grease injection section 11 is provided with an annular protrusion 13, which extends into the bearing raceway 31 to be greased. The length of the annular protrusion 13 extending into the bearing raceway 31 is equal to the width of the gap between the inner and outer rings of the bearing 3. The annular protrusion 13 fits tightly with the bearing raceway 31, and the clearance between the annular protrusion 13 and the bearing raceway 31 does not exceed 0.05mm. The annular protrusion 13 and the bearing raceway 31 can form a temporary, sealed channel pointing into the raceway, overcoming the problem that bearings without grease holes cannot be directly greased into the raceway. Moreover, without modifying the bearing itself, grease can be directly and accurately injected into the raceway area that needs the most lubrication.

[0023] The grease injection section 11 has an internal grease injection channel, which includes an axial hole 22 with a diameter of 0.5 mm that passes through the annular protrusion 13 and a radial hole 21 that communicates with the axial hole 22. The radial hole 21 is used to connect the grease injection gun. The radial hole 21 has a diameter of 2 mm and its axis is perpendicular to the axial hole 22. Alternatively, the radial hole 21 is a stepped hole that gradually decreases in size from the outside to the inside, which facilitates good docking and sealing with grease injection gun nozzles of different specifications or interfaces, improves the compatibility and reliability of the connection, and prevents grease leakage at the connection.

[0024] The manufacturing method and working process of the grease injection device are as follows:

[0025] Taking the RAU5008 standard series crossed roller bearing as an example, the bearing has an outer diameter of 66mm and an inner diameter of 50mm. First, the center diameter of the clearance between the inner and outer rings of the bearing 3 is measured to determine the diameter of the axial hole 22 of the grease injection device 1. The grease injection device is then drilled based on the center diameter. Specifically, a 0.5mm axial hole 22 is machined on the grease injection part 11 using an EDM machine, and it passes through the annular protrusion 13, ensuring that the outer wall of the annular protrusion 13 fits tightly with the inner diameter of the bearing raceway 31, with a maximum clearance of no more than 0.05mm.

[0026] After the grease injection device fits against the bearing inner diameter through the outer periphery of the fitting part 12, the device is stably positioned on the bearing end face, preventing wobbling or displacement, and facilitating grease injection by one-handed operation of the grease gun. The annular protrusion 13 can directly extend into the bearing raceway 31. The outlet of the axial hole 22 is located in the bearing raceway 31. A 2mm radial hole 21 is machined on the outer diameter of the side of the grease injection part 11 using an EDM drilling machine. Alternatively, the diameter of the radial hole 21 can be appropriately enlarged at the opening to facilitate good mating and sealing with grease gun nozzles of different specifications or interfaces, improving the compatibility and reliability of the connection and preventing grease leakage at the connection. Since coolant is sprayed in during EDM drilling, when the coolant is sprayed into the radial hole 21 and then flows out from the axial hole 22, it proves that the opening position is just right, and the radial hole 21 and the axial hole 22 are connected. Then, grease is injected from one end of the radial hole 21 of the device using a grease gun. The grease flows directly into the bearing raceway 31. As the bearing 3 rotates, the grease spreads quickly and evenly inside the bearing 3, thus achieving rapid grease injection. This rapid grease injection action can be achieved by repeating the operation.

[0027] The grease injection device 1 of this invention is primarily made of 45 steel with a hardness of HB280-320. This steel possesses high strength, hardness, and wear resistance, enabling the grease injection device 1 to withstand the high pressure generated by the grease injection gun without deformation or damage. In particular, the connection between the radial hole 21 and the axial hole 22 is less prone to cracking. Furthermore, the wear-resistant steel can withstand the lubricating grease and potential friction for a long time, extending the service life of the device.

[0028] It should be noted that the above embodiments are only used to illustrate the present utility model, but the present utility model is not limited to the above embodiments. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present utility model shall fall within the protection scope of the present utility model.

Claims

1. A quick grease injection device for crossed roller bearings without grease holes, characterized in that: The device includes an integral grease injection unit (1), which has a grease injection part (11) at the bottom. The bottom of the grease injection part (11) has a fitting part (12) with a diameter smaller than that of the grease injection part (11) on the same axis. The outer periphery of the fitting part (12) is in close contact with the inner wall of the bearing (3). The end face of the grease injection part (11) has an annular protrusion (13). The annular protrusion (13) extends into the bearing raceway (31) to be greased and fits tightly with the bearing raceway (31). The grease injection part (11) has a grease injection channel inside. The channel includes an axial hole (22) that passes through the annular protrusion (13) and a radial hole (21) that communicates with the axial hole (22). The radial hole (21) is used to connect the grease injection gun.

2. The quick grease injection device for cross roller bearings without oil injection holes according to claim 1, characterized in that: The outer diameter of the grease injection section (11) is equal to the outer diameter of the bearing (3).

3. The quick grease injection device for cross roller bearings without grease holes according to claim 1, characterized in that: The clearance between the annular protrusion (13) and the bearing raceway (31) shall not exceed 0.05 mm.

4. The quick grease injection device for cross roller bearings without grease injection holes according to claim 1, characterized in that: The length of the annular protrusion (13) extending into the bearing raceway (31) is equal to the width of the gap between the inner and outer rings of the bearing (3).

5. The quick grease injection device for cross roller bearings without grease holes according to claim 1, characterized in that: The diameter of the axial hole (22) is 0.5 mm.

6. The quick grease injection device for cross roller bearings without grease injection holes according to claim 1, characterized in that: The radial hole (21) has a diameter of 2 mm and its axis is perpendicular to the axial hole (22).

7. The quick grease injection device for cross roller bearings without oil injection holes according to claim 1, characterized in that: The radial hole (21) is a stepped hole that decreases in size from the outside to the inside.

8. The quick grease injection device for cross roller bearings without grease injection holes according to claim 1, characterized in that: The grease injection device (1) is made entirely of steel.

Images