Electromagnetic Switch Auxiliary Relay Radial Arrangement
Solution Overview
Problem
Conventional electromagnetic switch devices for starters, particularly in large-displacement engines, face challenges with increased coil resistance due to larger solenoid coil development length, leading to insufficient current supply and increased manufacturing costs, while protruding auxiliary relays compromise vehicle mountability and vibration resistance.
Innovation Solution
An electromagnetic switch device with an auxiliary relay where the main contact chamber and sub coil are arranged in parallel in a radial direction within a cylindrical terminal block, eliminating axial protrusions and integrating the auxiliary relay with the starter to enhance vehicle mountability and vibration resistance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If the solenoid coil of the auxiliary relay is wound around the outer circumference of the movable contact, then the auxiliary relay can be provided, but the development length of the coil is increased
Solution Approach 1:
The patent repositions the auxiliary relay from a radial arrangement (around the movable contact) to an axial arrangement (at the end of the movable contact). This dimensional change allows the coil to be wound in a compact axial direction rather than requiring a large radial development length, thereby reducing the coil's overall dimensions while maintaining functionality.
Solution Approach 2:
The auxiliary relay is nested within the existing electromagnetic switch structure, specifically utilizing the axial space at the end of the movable contact. This nesting approach allows the auxiliary relay to be integrated without requiring additional external space, and the coil can be compactly arranged within the nested configuration.
2Power
If the sectional area of the coil element wire is increased to supply needed current, then current supply is improved, but the size of the solenoid coil is enlarged and manufacturing cost is increased
Solution Approach 1:
By changing the winding arrangement from radial to axial, the patent reduces the coil's footprint in the radial direction. This allows the use of thinner wire (smaller sectional area) while maintaining the same magnetic field strength, because the axial winding path is more efficient and requires less total wire length to achieve the same number of effective turns.
Solution Approach 2:
The patent changes the geometric parameters of the coil arrangement, specifically the winding direction and compactness. This parameter change allows optimization of the wire sectional area - thinner wire can be used because the axial winding configuration achieves better space utilization and fewer total turns are needed to generate the required magnetic field.
3Volume of moving object
If the auxiliary relay protrudes in the axial direction, then the size of the solenoid coil is reduced, but vehicle mountability is deteriorated
Solution Approach 1:
The axial end of the movable contact serves multiple functions: it acts as the support structure for the auxiliary relay, provides the mounting surface for the relay, and maintains the electromagnetic circuit functionality. This multi-functionality eliminates the need for separate mounting structures that would increase overall size or compromise vehicle installation.
Solution Approach 2:
The auxiliary relay is nested at the axial end of the movable contact, utilizing the existing structural space rather than adding external protrusions. This nested configuration minimizes the overall envelope dimensions of the electromagnetic switch device, improving vehicle mountability while still accommodating the auxiliary relay functionality.
4Ease of manufacture
If the auxiliary relay is located away from the engine attachment surface, then assembly is simplified, but vibration response is increased
Solution Approach 1:
The patent merges the auxiliary relay mounting with the existing movable contact structure. By integrating the relay directly onto the movable contact assembly, the relay is positioned close to the engine attachment surface, which reduces vibration response while still allowing for straightforward assembly as the relay becomes part of the integrated electromagnetic switch unit.
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 configuration downsizes the sub coil, improves vehicle mountability, and enhances vibration resistance by eliminating axial protrusions and separating contact chambers, thereby improving the overall performance and reliability of the starter system.
Implementation Method 1
an auxiliary relay which includes a pair of sub fixed contacts, a sub movable contact, and a sub coil
Implementation Method 2
an electromagnetic switch which includes a pair of main fixed contacts, a main movable contact, an attraction coil, and a holding coil and which opens and closes an electric circuit for a motor via the pair of main fixed contacts, and when the attraction coil and the holding coil are energized, moves an overrunning clutch via a shift lever
Data Source
Figure 1~2
Figure 3~4
Figure 5~6
AI summary
Provided is an electromagnetic switch device for starter in which an auxiliary relay is provided and which has a small size and can be easily manufactured. The electromagnetic switch device (17) for starter includes: a main contact chamber (34) forming a space in which a pair of main fixed contacts (20) are located and a main movable contact 22 can move; and a sub contact chamber 35 forming a space in which a pair of sub fixed iron cores (A) (60), (B) (61) are located and a sub movable contact (29) can move; and a cylindrical terminal block 37 in which the main contact chamber (34) and the sub coil (32) are arranged so as to be adjacent to each other in the radial direction with a partition wall (36) provided therebetween and separating the sub coil (32) and the main contact chamber (34) from each other.