Blade Drive Device Curtain Locking Mechanism
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Electromagnetic drive-type focal plane shutters in cameras face challenges in miniaturization and quick shutter operation while ensuring impact resistance, as increasing detent torque for holding curtains in place slows the shutter and decreasing it may cause unintended curtain movement due to impacts.
Innovation Solution
A blade drive device with a substrate, movable front and rear curtains, electromagnetic actuators, locking portions, and a blade position holding mechanism that locks the curtains in place during opening and closing operations, allowing for miniaturization and impact resistance without increasing detent torque.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the detent torque of the electromagnetic actuator is increased to improve the holding force of the front curtain and rear curtain when power is not supplied, then the holding reliability is improved, but the shutter operation speed decreases and the device size increases
Solution Approach 1:
The invention divides the holding function into two separate mechanisms: the electromagnetic actuator's detent torque provides basic holding, while a dedicated blade position holding mechanism with locking portions provides enhanced holding during impacts. This segmentation allows the detent torque to be reduced for faster operation while the locking mechanism ensures impact resistance.
Solution Approach 2:
The blade position holding mechanism acts as an intermediary between the electromagnetic actuator and the curtains. It includes a holding member with locking portions that engage with grooves on the curtains, providing additional holding force during impacts without requiring increased detent torque from the actuator.
2Reliability
If the detent torque of the electromagnetic actuator is increased to ensure impact resistance, then the impact resistance is improved, but the device size increases
Solution Approach 1:
The holding function is segmented between the electromagnetic actuator and a separate blade position holding mechanism. The locking portions on the holding member provide impact resistance without requiring the actuator to be oversized, thus maintaining miniaturization while ensuring impact protection.
Solution Approach 2:
The blade position holding mechanism serves as an intermediary structure that provides impact resistance independently of the actuator size. The locking portions engage with the curtains to prevent impact-induced movement without requiring increased actuator dimensions.
3Reliability
If a blade position holding mechanism is disposed in each of the front curtain and rear curtain, then the impact resistance is improved, but the device complexity and size increase
Solution Approach 1:
The invention merges the blade position holding mechanisms for both curtains into a single integrated structure. The holding member includes locking portions that can engage with both the front curtain and rear curtain, eliminating the need for separate holding mechanisms and reducing overall device complexity while maintaining impact resistance.
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 enables miniaturization of the camera device, quickens shutter operation, and provides impact resistance by locking the curtains in place during impacts, preventing unintended movement and maintaining the open position without increased detent torque.
Implementation Method 1
electromagnetic drive-type FP shutter which actuates the front curtain and the rear curtain by using an electromagnetic actuator
Implementation Method 2
the electromagnetic drive-type FP shutter holds the open position of the front curtain and the rear curtain by using a detent torque (magnetic attraction force in a state where power is not supplied) of the electromagnetic actuator
Data Source
AI summary
There is provided a blade drive device including a substrate that has an opening, a front curtain and a rear curtain that are movable along an opening surface of the opening so as to open and close the opening, a front curtain electromagnetic actuator that actuates the front curtain, a rear curtain electromagnetic actuator that actuates the rear curtain, and that is capable of holding the rear curtain at an open position in a state having no power supply, a front curtain locking portion that interlocks with opening and closing operations of the front curtain, a rear curtain locking portion that interlocks with opening and closing operations of the rear curtain, and a blade position holding mechanism that is capable of entry and escape between an entry position which enters each operation trajectory of the front curtain locking portion and the rear curtain locking portion in response to the opening and closing operations of the front curtain and the rear curtain and an escape position escaped from the operation trajectory. At the entry position, the blade position holding mechanism can engage with both the front curtain locking portion and the rear curtain locking portion, thereby regulating the movement of the front curtain and the rear curtain in the closing direction.