© Copyright 2015 Oki Electric Industry Co., Ltd. S OSDC CONFIDENTIAL Reed Switch Basics OKI Sensor...

Copyright 2015 Oki Electric Industry Co., Ltd. S OSDC CONFIDENTIAL 2 A switch composed of two (reed) blades created from magnetic material and sealed with inert gas. The switching mechanism relies on external magnetic waves to magnetize the blades and initiate contact.

Copyright 2015 Oki Electric Industry Co., Ltd. S OSDC CONFIDENTIAL 3 A reed switch consists of; Two reed blades made from ferromagnetic permalloy Glass Tube Plating applied to the contact surfaces Nitrogen based inert gas pumped into the glass tube Pb-free solder dipped terminals Contact surface are plated with platinum group metals, such as iridium and rhodium. Contact surfaces also go under oxygen treatment to stabilize contact resistance. The fusing machine brings two reeds and a glass tube together to form the reed switch. Inert gasor vacuumGlass tubeHermetic seal PB-free lead solder Permalloy (Fe+Ni) Gold (Au) Rhodium (Rh)+[Iridium (Ir)] A layer of Au & a PG metal is applied upon the pressed permalloy Placing a magnetic field close to the reed switch induces a magnetic north and south pole in the ferromagnetic permalloy leads. The contact surfaces attract and close in what is considered the ON state. As the magnetic field is removed the contacts are restored and open into the OFF state.

Copyright 2015 Oki Electric Industry Co., Ltd. S OSDC CONFIDENTIAL 4 OFF State Operation ON State Operation N poleS pole N pole Inert gasor vacuum Reed blade contacts PB-free lead solder Glass tubeHermetic seal

Copyright 2015 Oki Electric Industry Co., Ltd. S OSDC CONFIDENTIAL 5 Shipment Permalloy leads Glass tube Reed blade Sealing Machine Plating Machine Sealing portion (Both top and bottom) Undercoat Surface Plating Reed blade Permalloy lead Cut and Press Cut & Press Magnetic Annealing Contact surface plating Surface treatment Glass sealing Solder dip Electrical inspection Physical inspection Packaging Final inspection K1 K2 Annex

Copyright 2015 Oki Electric Industry Co., Ltd. S OSDC CONFIDENTIAL 7 Glass sealing is achieved using in-house designed and produced automated sealing machines [Surface Treatment] After plating on the reed blades contact surface, the blades undergo high temperature oxidation treatment. This treatment removes moisture and carbon particles from the surface, leading to stable electrical resistance throughout the reed switchs lifespan. As the reed switch contains ferromagnetic leads there is a probability that particles end up inside the glass of the reed switch. Alongside electrical characteristics measurement, the below process of magnetic flux scanning removes particles from all reed switches. [Electrical MeasurementPhysical Examination] All reed switches under electrical characteristics and physical examination [Glass Sealing Automation] [Magnetic Flux Scanning]

Copyright 2015 Oki Electric Industry Co., Ltd. S OSDC CONFIDENTIAL 10 The sensitivity of OKI Reed Switches are measured using the OKI Standard Coil. Other brands of reed switches have sensitivities which may not be equivalent.

Copyright 2015 Oki Electric Industry Co., Ltd. S OSDC CONFIDENTIAL 12 Case 1: X-Y Characteristic (Horizontal) Position 1: Lines of magnetic force flow through ON Position 2: Lines of magnetic force do not flow through OFF Position 3: Lines of magnetic force flow through ON When magnetic drive is applied, depending on the magnet position the ON & OFF operating position may vary. Depending on the magnetic fields direction, the ON and OFF ON & OFF operating position may vary. With a strong magnet OR with a high sensitivity reed switch(AT is small) there are areas on the far edges of the terminals that are ON operating positions(3 point operation).

Copyright 2015 Oki Electric Industry Co., Ltd. S OSDC CONFIDENTIAL 13 Case 1: X-Y Characteristic (Horizontal)Case 2: X-Z Characteristic (Horizontal) 90Clockwise Case 3: X-Y Characteristic (Vertical) Magnet 90Clockwise

Copyright 2015 Oki Electric Industry Co., Ltd. S OSDC CONFIDENTIAL 16 Stop Lamp Switch Lamp Expiration Sensor Seatbelt Sensor Engine Temperature Sensor Power Seat Position Sensor Fuel Tank Level Indicator Seat Position Sensor Brake Fluid Level Indicator (FLI) Airbag Sensor Speed Sensor Equipped with a liquid ammonia tank, this liquid is sprayed into the exhaust gas to produce ammonia gas. This ammonia gas is then used in the treatment of nitrogen oxides(NO X ) in exhaust gas. Liquid Ammonia Tank Dosing Control Engine Oxidation SCR Post treatment Temperature Sensor Selective Catalytic Reduction System Window Wash Tank Level Indicator Liquid Ammonia Tank Level Indicator Brake Fluid Level Indicator (FLI) Engine Oil Level Indicator Fuel Tank Level Indicator

Copyright 2015 Oki Electric Industry Co., Ltd. S OSDC CONFIDENTIAL 17 Rice Cooker Washing Machine Air Conditioner Dish Washer Refrigerator Temperature Sensor Oneba Sensor Pot Sensor Open/Close Sensor Cleaner Position Sensor Open/Close Sensor Temperature Sensor Open/Close Sensor

Copyright 2015 Oki Electric Industry Co., Ltd. S OSDC CONFIDENTIAL 18 Bidet Toilet Seat Coffee Maker Electric Shaver Humidifier Electric Toothbrush Electric Hot Pot Water Level Sensor Power ON/OFF Switch Water Level Sensor Power ON/OFF Switch

Copyright 2015 Oki Electric Industry Co., Ltd. S OSDC CONFIDENTIAL 19 Electric Thermometer Open/Close Sensor Flow Sensor Reset Switch Gas Meter Water Heater Capacity Sensor Rotation Sensor Magnetic Sensor Bicycle Meter Slot Machine Electric Reel IC Tester Security Systems Reed Relay Power ON/OFF Switch

Copyright 2015 Oki Electric Industry Co., Ltd. S OSDC CONFIDENTIAL 22 Reed Switch Traits Advantages ON State resistance is low, OFF state resistance is high No operating electricity needed Can handle direct loads of DC/AC Usable in any environment

Copyright 2015 Oki Electric Industry Co., Ltd. S OSDC CONFIDENTIAL 26 Refrigerator door open/close sensor With the reed switch set in the main unit, opening the door opens the reed switch beginning a timer. When the timer reaches a certain count an alarm sounds. Magnet enclosed in the door

Copyright 2015 Oki Electric Industry Co., Ltd. S OSDC CONFIDENTIAL 28 Smart Meters (Gas, Water) Flow of water/gas is measured by the rotation of the magnet triggering counting over the reed switch circuit. Magnet mm

Copyright 2015 Oki Electric Industry Co., Ltd. S OSDC CONFIDENTIAL 29 Water Level Sensor Coffee Maker/Electric Water Pot) As the float with magnet inside goes down with the water level, the [Empty] switch turns ON to stop the heater. As the water empties, water is pumped in and stops when the [Full] switch turns ON. As the float with magnet inside goes down with the water level, the [Empty] switch turns ON to stop the heater. As the water empties, water is pumped in and stops when the [Full] switch turns ON. Magnet Float Full Empty Pump Heater

Copyright 2015 Oki Electric Industry Co., Ltd. S OSDC CONFIDENTIAL 30 Multiple point fluid level sensor (Gasoline/Diesel Tank) With magnets fitted into the floats, as the fluid level fluctuates the multiple switches turn off and on to indicate the level of fluid.

Copyright 2015 Oki Electric Industry Co., Ltd. S OSDC CONFIDENTIAL 31 Power Windows detection sensor 2 Reed switches on the motor detect the change in rotation speed. Magnets on the motor gear turn the switches to the ON state allowing detection of the rotation direction and rotation speed.

© Copyright 2015 Oki Electric Industry Co., Ltd. S OSDC CONFIDENTIAL Reed Switch Basics OKI Sensor...

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