Electrospindle Bearing Preload via Cooling Liquid Pressure
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing electrospindles for machine tools face challenges in having a simple and variable preload system for their bearings, often relying on mechanical or hydraulic means that increase wear and complexity.
Innovation Solution
The use of cooling liquid to radially preload bearings, with an elastic self-lubricating element, allowing for adjustable preload without additional mechanical or hydraulic systems, leveraging the existing cooling system for both preload and lubrication.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If traditional preloaded sliding bushes are used for bearing preload, then the bearings are preloaded to provide adequate rigidity, but mechanical wear increases and the system complexity increases
Solution Approach 1:
The patent replaces the traditional mechanical sliding bush preload system with a hydraulic preload system using cooling liquid pressure. The cooling liquid is directed into the bearing preload chamber to apply radial preload force to the bearings, eliminating the need for mechanical sliding bushes and reducing mechanical wear while maintaining the required rigidity.
Solution Approach 2:
The patent uses hydraulic pressure from the cooling liquid to apply preload to the bearings. The cooling liquid pressure is regulated to provide the necessary radial preload force, replacing mechanical means with a hydraulic system that reduces wear and simplifies the overall structure.
2Force
If additional mechanical or hydraulic systems are added for bearing preload, then the preload can be applied, but the device complexity increases
Solution Approach 1:
The patent makes the cooling liquid system serve dual functions: cooling the electrospindle and applying radial preload to the bearings. By utilizing the existing cooling liquid infrastructure and adding a preload chamber with pressure regulation, the system achieves bearing preload without requiring separate mechanical or hydraulic systems, thereby reducing overall device complexity.
Solution Approach 2:
The patent merges the cooling function and bearing preload function into a single integrated system. The cooling liquid serves both to cool the electrospindle and to provide radial preload to the bearings through pressure regulation, combining two previously separate functions into one unified system.
3Force
If fixed preload systems are used, then the bearings are preloaded, but the preload cannot be varied
Solution Approach 1:
The patent implements a dynamic preload system where the radial preload force can be varied by adjusting the cooling liquid pressure. The pressure regulation mechanism allows the preload to be adapted to different operating conditions, replacing fixed mechanical preload systems with a controllable hydraulic system that provides flexibility and adaptability.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach reduces mechanical wear and simplifies the preload system by using cooling liquid pressure to apply radial preload, enabling adjustable bearing support without additional components, enhancing the electrospindle's rigidity and operational efficiency.
Implementation Method 1
The preload is obtained by means of an elastic element, preferably made of selflubricating material, which considerably reduces wear of the mechanical components in contact, contrary to the traditional systems with preloaded sliding bushes.
Implementation Method 2
The preload is obtained by means of an elastic element, preferably made of selflubricating material, which considerably reduces wear of the mechanical components in contact
Data Source
Figure 1
Figure 2
AI summary
An electrospindle (10) with preloaded bearings for a machine tool comprising: an external container (12); a drive shaft (14) rotatable with respect to said external container (12), by means of front bearings (15) and rear bearings (16), located at the two ends of said drive shaft (14); a series of channels positioned inside said electrospindle (10) to cause a cooling liquid of said electrospindle (10) to flow; characterized in that at least one cooling channel (30) of said electrospindle (10) is provided positioned circularly external to said rear bearings (16) designed to provide a radial force to said rear bearings (16) equal to the pressure of said cooling liquid; said at least one cooling channel (30) is positioned between a circular housing ring (22) housing the rear bearings (16) and a circular external flange (20) which is fixed to the external container (12); a flat and circular gasket (31) is positioned between said at least one cooling channel (30) and said external flange (20). (Fig. 1)