Segmented Labyrinth Seal for Main Spindle Coolant Resistance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional main spindle devices face challenges in effectively preventing high-pressure cutting fluids, such as coolant, from entering the gap between the main spindle and the housing, leading to potential bearing seizure due to the lack of a complex seal structure, which complicates rotation balance and integration with the main spindle.
Innovation Solution
A labyrinth-forming annular groove is created on the main spindle, with a housing lid member divided into pieces to form a complex labyrinth seal, and an air sealing system is implemented using annular grooves and air supply passages to reduce coolant entry, while a discharging passage is provided to manage any entering fluid.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a conventional air sealing structure is used to prevent coolant entry, then sealing function is provided, but high-pressure coolant can still penetrate through the simple gap structure
Solution Approach 1:
The housing lid member is divided into multiple segments (first housing lid member and second housing lid member) that can rotate relative to each other, creating a complex multi-stage sealing path that effectively blocks high-pressure coolant penetration while maintaining reliable sealing function
Solution Approach 2:
The sealing structure transitions from a simple radial gap to a multi-dimensional complex path involving axial and radial movements through the rotatable segmented housing lid members, creating a labyrinthine sealing mechanism that prevents coolant entry
2Reliability
If a complex seal structure is introduced to prevent coolant entry, then sealing performance improves, but rotation balance of the main spindle deteriorates
Solution Approach 1:
The housing lid member is designed to be rotatable rather than fixed, allowing dynamic adjustment during operation. This rotational capability maintains balance by accommodating thermal expansion and manufacturing tolerances while the segmented structure provides complex sealing without compromising rotation balance
3Reliability
If a separate sealing member is fitted onto the main spindle to create sealing, then sealing function is achieved, but integration complexity and manufacturing difficulty increase
Solution Approach 1:
The sealing function is merged into the housing lid member itself through the rotatable segmented structure, eliminating the need for separate sealing members. This integration simplifies manufacturing and assembly while maintaining effective sealing function against high-pressure coolant
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
The solution effectively suppresses the entry of coolant and foreign matter into the bearing area, enhancing the sealing performance and preventing bearing seizure, while allowing for easier installation and maintenance without the need for separate sealing members.
Implementation Method 1
a non-contact, air sealing structure that effects sealing by discharging compressed air (hereinafter referred to as 'air') through a gap between a housing, which includes a housing body 20 and a bearing holding lid member 130, and a main spindle 110
Implementation Method 2
a labyrinth-forming annular groove is formed, in a circumferential direction of the main spindle, on a protruding portion of the main spindle that protrudes from the housing on a front side along a rotation axis of the main spindle
Data Source
Figure 1A~1B
Figure 2
Figure 3A~3C
AI summary
In a main spindle device (1) provided with a housing (20, 30) and a main spindle (10), a labyrinth-forming annular groove (MR) is formed, in the circumferential direction of the man spindle (10), on the outer circumferential surface of a protruding portion of the spindle that protrudes from the housing (20, 30) on the front side. A housing lid member (40) having a protruding portion that is inserted into the labyrinth-forming annular groove (MR) so as not to contact an inside surface of the labyrinth-forming annular groove (MR) all around the periphery is fixed to the housing (20, 30) on the front side thereof and forms a labyrinth seal portion (60) between the protruding portion and the labyrinth-forming annular groove (MR). The housing lid member (40) is constructed so that the housing lid member (40) can be divided into at least two pieces with respect to the circumference of the labyrinth-forming annular groove (MR).