Two-shaft vacuum pump release structure for piston contact safety
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Twin-shaft vacuum pumps face a risk of piston contact, leading to potential damage from flying fragments and increased rotational energy, which poses a safety hazard as higher speeds increase the stored energy and risk.
Innovation Solution
A release structure is introduced between the piston surfaces and shaft bearings, allowing relative rotation and reducing torque transmission, featuring a clamping ring and sleeve-like extension, and optionally a deformation zone to absorb kinetic energy through plastic deformation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the rotational speed of the shafts is increased to achieve higher pumping speeds, then the productivity is improved, but the rotational energy stored in the rotating parts increases non-linearly, leading to increased risk and harmful factors
Solution Approach 1:
The patent implements a release structure (sleeve-like extension with clamping ring) that acts as a predetermined safety mechanism. When piston contact occurs, this structure allows relative rotation between shaft and piston, dissipating the suddenly released rotational energy through controlled slippage rather than transmitting it to the bearings and housing. This beforehand cushioning protects the pump from damage even at high rotational speeds.
2Power
If a rigid connection between shaft and piston is used to ensure reliable torque transmission, then the power transmission is improved, but the device complexity increases due to additional release mechanisms
Solution Approach 1:
The patent merges the torque transmission function with the safety release function into a single integrated connection structure. The sleeve-like extension with clamping ring simultaneously transmits torque during normal operation and provides controlled slippage during abnormal conditions. This merging eliminates the need for separate rigid connections and independent release mechanisms, reducing overall device complexity while maintaining both power transmission and safety functions.
3Manufacturing precision
If the shaft and piston are manufactured as a single piece or joined by material bond, then the manufacturing precision is improved, but the ease of manufacture decreases due to additional design constraints
Solution Approach 1:
The patent segments the shaft-piston connection into separable components (shaft with clamping ring and piston with sleeve-like extension) that are joined through a standardized frictional connection. This segmentation allows each component to be manufactured independently with standard tolerances, then assembled together. The clamping ring design ensures precise alignment during assembly while maintaining manufacturing simplicity, avoiding the need for complex single-piece machining or specialized bonding processes.
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 design significantly reduces the risk of damage by minimizing the transmission of moments to the bearings and housing, enhancing safety while maintaining structural simplicity and efficiency.
Implementation Method 1
The inner surface of this extension is pressed onto the shaft by means of a clamping ring that is closed in its circumferential direction. The resulting frictional connection is released when high forces are introduced into the piston.
Implementation Method 2
In this deformation zone, additional kinetic energy is dissipated through plastic deformation, thus further reducing the moments transmitted to the bearings.
Data Source
Figure 1
Figure 2~3
Figure 4~5
AI summary
The vacuum pump has two shafts (10,14) and two pistons (12,16) which are connected with the shafts respectively. The vacuum pump has a drive which displaces the shaft in rotation and a bearing (22,24,26,28) for rotatable support of the shaft. A releasing structure is provided between the piston and the bearing.