An axial semi-closed hydrodynamic-rolling bearing combined supporting spindle system of an inertia friction welding machine

Abstract

An axial semi-closed dynamic and static pressure bearing-rolling bearing combined supporting spindle system of an inertia friction welding machine, the present application relates to the system design of axial bearing and rolling bearing supporting part of axial semi-closed spindle system. The present application aims to realize the semi-closed axial bearing and rolling bearing supporting structure, realize the closed type within the pre-tightening range of back pressure bearing (3), realize the open type outside the pre-tightening range of back pressure bearing (3), so that the assembly is simple and the manufacturing cost is reduced. Back pressure bearing (3) improves the carrying capacity of liquid dynamic and static pressure thrust bearing (11). Back pressure bearing (3) improves the stability of liquid dynamic and static pressure thrust bearing (11) under the condition of large load and high speed, reduces the scraping work of liquid dynamic and static pressure thrust bearing bush, and improves the production efficiency. Spring structure (2) reduces the noise of back pressure bearing (3) during work. The specific structure is shown in abstract drawing 1.

Description

Technical Field

[0001] This invention belongs to the technical field of friction welding equipment and relates to an axial semi-closed dynamic and static pressure bearing-rolling bearing combined support spindle system for an inertial friction welding machine. Background Technology

[0002] Inertial friction welding technology utilizes an electric motor (18) to provide potential energy to an inertial energy storage disk (17), then turns off the motor (18), and applies a forging force to the moving side workpiece (21) to bring the two workpieces into contact. Due to the heat generated by friction on the surface, the surfaces of the two workpieces enter a high-temperature state. The forging force causes elastoplastic deformation at the contact point of the two workpieces, and penetration occurs between the two workpieces, i.e., the two workpieces are welded together. However, the welding process requires ensuring that the oil film structure of the hydrostatic thrust bearing (11) has a certain rigidity and that the oil film is stable during the welding process. Therefore, a thrust roller bearing is selected as a back pressure bearing (3) at the end of the spindle of the inertial friction welding machine by pre-tightening. In this way, the hydrostatic thrust bearing (11) is more stable in terms of load bearing when rotating at high speed and bearing the forging force, ensuring the minimum load-bearing oil film gap. Meanwhile, in terms of assembly and processing, since only one side of the hydrostatic thrust bearing (11) is used as the main axial bearing, the efficiency of the factory to scrape the bearing shell of the hydrostatic thrust bearing is improved, and the processing and manufacturing costs are reduced. Summary of the Invention

[0003] The technical problem to be solved by this invention is to implement semi-closed control of the spindle system during the welding process. That is, the spindle system is under closed control when it is not subjected to upsetting force, so that the oil film stiffness when the spindle rotates at high speed and is not subjected to upsetting force can be improved to obtain better resistance to external forces. In this process, since the preload is always present, this process has a feedback effect, that is, it forms a closed system. However, when subjected to upsetting force, because the upsetting force is far beyond the preload range of the back pressure bearing (3), it exceeds the feedback limit, making the spindle system open. This greatly reduces the complexity of the spindle system operation, and the structure is simple and easy to use, easy to assemble, scrape, maintain and produce. In view of the above, an axial semi-closed dynamic and static pressure bearing-rolling bearing combined support spindle system for inertial friction welding machine is proposed.

[0004] The axial semi-enclosed dynamic and static pressure bearing-rolling bearing combined support spindle system of the inertia friction welding machine is implemented according to the following structure:

[0005] An axial semi-closed dynamic and static pressure bearing-rolling bearing combined support spindle system for an inertial friction welding machine, the overall working process of which is as follows: when the inertial friction welding machine is stopped, the moving side mechanism (22) is at the rear end of the fixed end travel guide (25), making the intermediate space larger and facilitating the installation of the workpiece. When welding begins, the inertial friction welding machine uses the moving end travel guide (23) to bring the moving side workpiece (21) close to the rotating side workpiece (20), starts the motor (18), drives the rotating side spindle (19) to rotate and makes the inertial energy storage disk (17) have the rotational inertia required for welding the workpiece. During the working process, the back pressure bearing (3) is always in axial preload. In the state, the motor (18) is stopped, and the upsetting force is applied through the moving side mechanism (22). The moving side weldment (21) and the rotating side weldment (20) come into contact and rub against each other. The back pressure bearing (3) is in a relaxed state due to the upsetting force, generating vibration and noise. The spring structure (2) is responsible for pressing the back pressure bearing (3) after the upsetting force is applied to reduce vibration and noise. Due to the friction of the contact part, the potential energy is converted into heat energy, causing the contact part area to enter a high temperature state. Under the action of the upsetting force, elastic-plastic deformation occurs until the potential energy is exhausted. The rotating side workpiece (20) and the moving side workpiece (21) are welded together, and the inertial friction welding process ends.

[0006] In the friction welding process, a preload is applied to the back pressure bearing (3). A back pressure bearing (3) is added to the end of the rotating side spindle (19) of the friction welding machine, and a preload is applied to the back pressure bearing (3). The preload is about 50% of the axial limit pressure of the selected back pressure bearing (3). This allows the oil film of the liquid dynamic and static pressure thrust bearing (11) to have a certain rigidity when the workpiece (20) on the rotating side rotates at high speed and is not subjected to upsetting force. This prevents axial movement of the workpiece (20) on the rotating side when it rotates at high speed but is not subjected to upsetting force, thereby improving welding accuracy and improving the control accuracy of the axial shortening at the weldment interface after welding.

[0007] In the aforementioned friction welding, the inertial friction welding machine spindle system with back pressure bearing (3) as back pressure is called semi-closed because during the welding process, only when the upsetting force is less than or equal to the preload force can the hydrostatic thrust bearing (11) form a feedback structure through constant flow oil supply, that is, the inertial friction welding machine spindle system is closed, which is beneficial to maintain the oil film stiffness and stability of the hydrostatic thrust bearing (11) when the inertial energy storage disk (17) is working, and prevent the spindle system from axial movement. When the upsetting force exceeds the preload force, it exceeds the oil film feedback range of the hydrostatic thrust bearing (11), and the inertial friction welding machine spindle system forms an open structure. As long as the stability of the constant flow oil supply system is ensured, the welding stability can be guaranteed. The structure is simple and easy to maintain. Therefore, for the above reasons, this structure is called the inertial friction welding machine axial semi-closed hydrostatic bearing-rolling bearing combined support spindle system.

[0008] In the aforementioned friction welding, when the inertial friction welding machine is working, the rotating side workpiece (20) is subjected to upsetting force, causing the back pressure bearing (3) to relax, and the rotating side spindle (19) of the inertial friction welding machine is in a rotating state. Therefore, the back pressure bearing (3) will vibrate, generate noise, and even have some negative impact on the bearing life. To address this issue, a spring structure (2) is added to the rear end of the back pressure bearing (3) to reduce the vibration and noise of the end back pressure bearing (3) when the rotating side spindle (19) of the inertial friction welding machine is rotating at high speed and subjected to upsetting force, thereby reducing the impact of vibration on the bearing life. Although the pressure of the spring structure (2) can be considered as part of the preload, since the pressure of the spring structure (2) is much different from the preload of the bearing, the pressure of the spring structure (2) can be omitted when calculating the preload.

[0009] In the friction welding process, at the front end of the rotating spindle (19) of the inertial friction welding machine, two rows of angular contact ball bearings (14) are designed as supports to support the weight of the components at the front end of the spindle and the bearing itself. Since the clearance of the double row angular contact ball bearings (14) can be adjusted, the rolling elements can both revolve and rotate within the raceways on both sides, preventing the rolling elements from damaging the raceways by projectile motion. Since the contact area between the rolling elements and the raceways in the double row angular contact ball bearings (14) is small, the selection of appropriate lubricating oil can effectively reduce the heat generation of the bearing and quickly dissipate the heat generated by the bearing, thereby reducing the thermal deformation of the double row angular contact ball bearings (14). The radial load capacity of the double row angular contact ball bearings (14) also meets the load-bearing standard of the spindle system. Therefore, double row angular contact ball bearings (14) are selected at the front end. Similarly, according to the radial load characteristics of the spindle system, double row cylindrical roller bearings (10) are selected as the radial load bearing between the back pressure bearing (3) and the hydrostatic thrust bearing (11).

[0010] The force balance diagram for the friction welding process described herein is attached to the instruction manual. Figure 3 lateral pressure F C Equal to the forging force F D With back pressure side pressure F B The sum of the two. When the preload of the back pressure bearing (3) is too large, the oil chamber pressure of the hydrodynamic thrust bearing (11) will increase, which will increase the temperature rise of the oil film, increase energy loss, increase the thermal deformation of the bearing bush, and reduce the spindle rotation accuracy. When the back pressure preload of the back pressure bearing (3) is too small, the stiffness of the oil film of the hydrodynamic thrust bearing (11) is low, the ability to resist external forces is weak, and it is easily affected by the external environment, thus causing axial movement. Based on experience and the relevant calculation conditions of bearing life, the preload is approximately 50% of the bearing's axial limit load.

[0011] Invention effects:

[0012] This invention applies a preload to the back pressure bearing (3) at the end of the spindle system, resulting in a semi-closed control characteristic for the entire inertial friction welding machine spindle system. When not subjected to upsetting force, the presence of the back pressure bearing (3) in the spindle system increases the oil film stiffness of the hydrostatic thrust bearing (11), enabling the hydrostatic thrust bearing (11) to resist external forces more effectively under no-load conditions, thereby improving its oil film stiffness and reducing axial movement of the spindle system. When the main bearing is subjected to upsetting force, since the upsetting force is much greater than the preload provided by the back pressure bearing (3), the system is in an open state during this process, making the oil film of the hydrostatic thrust bearing (11) more stable, thereby improving welding accuracy. The semi-closed spindle system is simple to process and reduces the amount of bearing scraping work during assembly, improving manufacturing efficiency. Attached Figure Description

[0013] Figure 1 Schematic diagram of the axial semi-enclosed dynamic and static pressure bearing-rolling bearing combined support spindle system of an inertial friction welding machine

[0014] Figure 2 Schematic diagram of the overall structure of the inertial friction welding machine

[0015] Figure 3 Schematic diagram of the positions of the side pressure and back pressure of the dynamic and static thrust bearing (11) when the axial semi-closed dynamic and static pressure bearing-rolling bearing combined support spindle system of an inertial friction welding machine is subjected to upsetting force.

[0016] Figure label:

[0017] In the diagram, 1-end cover, 2-spring structure, 3-back pressure bearing, 4-retaining ring, 5-reducer transmission gear, 6-retaining ring, 7-keyway, 8-chassis component, 9-retaining ring, 10-double row cylindrical roller bearing, 11-liquid hydrostatic bearing, 12-hydrostatic bearing base, 13-retaining ring, 14-double row angular contact ball bearing, 15-retaining ring, 16-oil inlet pipe, 17-inertia storage disk, 18-motor, 19-rotating side spindle, 20-rotating side weld (workpiece), 21-moving side weld (workpiece), 22-moving side mechanism, 23-stroke guide rail, 24-inertia friction welding machine base, 25-fixed end stroke guide rail. Detailed Implementation

[0018] See Figure 2When installing friction-welded workpieces, the moving side mechanism (22) is located at the rear end of the moving end travel guide rail (23). At this time, the distance between the rotating side and the moving side of both mechanisms is the greatest, which facilitates the installation and disassembly of the workpieces. During welding preparation, the moving end travel guide rail (23) is slowly moved by the motor until the two workpieces are close together. The positions of the workpieces to be welded on both sides are about a few millimeters apart. At this time, the moving end travel guide rail (23) is locked. The motor (18) is run, and the speed is transmitted to the rotating side spindle (19) through the reducer (5), so that the inertial energy storage disk (17) obtains potential energy and at the same time the rotating side workpiece (20) reaches the predetermined speed. After that, the motor (18) is removed, and the spindle continues to rotate the rotating side workpiece (20) at the original speed through inertia. In the latter half of the welding process, the moving side mechanism (22) operates through its internal mechanism to bring the moving side workpiece (21) into a working state of small displacement and large upsetting force, so that the moving side workpiece (21) comes into contact with the rotating side workpiece (20). When the rotating side spindle (19) is also rotating at high speed and subjected to a large upsetting force, since the upsetting force is much greater than the back pressure preload, there is no feedback in this process, that is, the system is an open structure. When the spindle system is installed, the preload is applied through the back pressure bearing (3), so that the oil film of the hydrostatic bearing (11) has a certain rigidity. In the early stage of welding, when the spindle rotates at high speed but is not subjected to upsetting force, feedback can be provided, and the spindle system constitutes a closed structure. However, it should be noted that when the rotating spindle (19) is subjected to upsetting force, the preload of the back pressure bearing (3) fails, so the back pressure bearing (3) is in a relaxed state, which will cause vibration and noise. Therefore, a spring structure (2) is added to the rear end of the back pressure bearing (3) to reduce the vibration of the back pressure bearing (3) and help improve the service life of the back pressure bearing (3). The magnitude of the preload is determined by empirical value, which is approximately 50% of the axial ultimate bearing capacity of the back pressure bearing. The workpieces on both sides generate heat due to friction. The potential energy is converted into thermal energy, resulting in a high temperature at the interface. The moving side workpiece (21) and the rotating side workpiece (20) undergo elastoplastic deformation, and the materials interact with each other until the potential energy is exhausted and the temperature drops to the point where the material structure does not change, thus announcing the end of the welding process.

Claims

1. An axial semi-enclosed dynamic and static pressure bearing-rolling bearing combined support spindle system for an inertial friction welding machine, characterized in that: The axial semi-closed dynamic and static pressure bearing-rolling bearing combined support spindle system of the inertial friction welding machine includes an end cover (1), a spring structure (2), a back pressure bearing (3), a double row cylindrical roller bearing (10), a liquid dynamic and static pressure bearing (11), a double row angular contact ball bearing (14), an inertial energy storage disk (17), a motor (18), a rotating side spindle (19), a rotating side weldment (20), a moving side weldment (21), a moving side mechanism (22), and a travel guide rail (23). A liquid hydrostatic bearing (11) is installed on the front side of the rotating side spindle (19) of the inertial friction welding machine. A double-row angular contact ball bearing (14) is installed on the front side of the liquid hydrostatic bearing (11). The double-row angular contact ball bearing (14) serves as a support component and its clearance is adjustable. An inertial energy storage disk (17) is installed on the front side of the double-row angular contact ball bearing (14). The rotating side spindle (19) can drive the rotating side weldment (20) to rotate. A back pressure bearing is added to the end of the rotating side spindle (19) of the inertial friction welding machine. A spring structure (2) is installed at the rear end of the back pressure bearing (3) to contact the back pressure bearing (3). The spring structure (2) is installed at the rear end of the back pressure bearing (3). End caps are provided; a double-row cylindrical roller bearing (10) is provided between the liquid hydrostatic bearing (11) and the back pressure bearing (3) as a radial load bearing; the moving side weldment (21) is provided on the moving side mechanism (22), and the travel guide rail (23) allows the moving side mechanism (22) to move back and forth; when welding begins, the inertial friction welding machine brings the moving side weldment (21) close to the rotating side weldment (20) through the travel guide rail (23), starts the motor (18), drives the rotating side spindle (19) to rotate and makes the inertial energy storage disk (17) have the rotational inertia required for welding the workpiece, and during the operation, the back pressure bearing (3) The back pressure bearing (3) is always in an axial preload state. When the workpiece (20) on the rotating side rotates at high speed and is not subjected to upsetting force, the hydraulic hydrostatic bearing (11) increases the stiffness of the bearing oil film, so that the workpiece (20) on the rotating side can avoid axial movement when it rotates at high speed but is not subjected to upsetting force. The motor (18) is stopped, and upsetting force is applied through the moving side mechanism (22). The moving side weldment (21) contacts and rubs with the rotating side weldment (20). The back pressure bearing (3) is in a relaxed state due to the upsetting force, generating vibration and noise. The spring structure (2) is responsible for applying the upsetting force. After the upsetting force is applied, the back pressure bearing (3) is pressed to reduce vibration and noise. Due to friction, the potential energy of the contact part between the moving side weldment (21) and the rotating side weldment (20) is converted into heat energy, causing the contact part area to enter a high temperature state. Under the action of the upsetting force, elastic-plastic deformation occurs until the potential energy is exhausted. The rotating side weldment (20) and the moving side weldment (21) are welded together, and the inertial friction welding process ends. During the welding process, when the external force is less than or equal to the preload force, the bearing oil film of the liquid hydrostatic bearing (11) forms a feedback structure through constant flow oil supply, that is, the spindle system of the inertial friction welding machine forms a closed structure.When the external force exceeds the preload, it exceeds the oil film feedback range of the hydrostatic bearing (11), and the spindle system of the inertial friction welding machine forms an open structure.

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