Security of electricity

Why we should pay attention to security of electricity:

In order to avoid self-harm, damage to personal or public property Note:

Do not touch high-voltage objects

Do not close to a high-pressure objects

Do not touch the micro switches with a wet hand

Human security voltage is not higher than 36 volts

With great power must be grounded electrical line

Can not use your body to connect the FireWire and ground line

The body can not use FireWire connectivity and zero line

With the use of the total electrical power can not be too high, otherwise excessive current caused a fire

You can not pull him immediacy use you hand,you must cut the master switch,then use a dry stick discission him and the wire.

naphthente

Naphthenates are sorts of carboxylic acids which contain saturated cyclic hydrocarbons such as cyclopentane and cyclohexane; acids of this kind are known as naphthenic acids. The acids are separated from the gas oil fraction in petroleum distilling. Naphthenates are formed through interaction of naphthenic acids in crude oil with metal ions such as calcium and sodium. Insoluble in either the oil or water phase, and with a density between that of oil and water, naphthenates tend to accumulate at the oil/water interface and act as surfactants to help stabilize emulsions.

The most widely used naphthenates are certain metallic soaps. These soaps are soluble, not in water but in many organic substances. The metallic naphthenates are yellowish-brown and, depending on metallic content, viscous liquids, sticky compounds or soft, solid substances. The metallic content can vary between about 6% and about 40%. 

 

Naphthenates are mostly used as an ingredient in paints, to accelerate the drying of the painted surface. When the binder in paint comes into contact with atmospheric oxygen, the intention is for the binder to cross-link and become a solid layer, i.e. to set. The metallic part of the siccative accelerates absorption of atmospheric oxygen, catalyses the formation of free radicals, and the binder reacts – dries – more rapidly. Most often a combination of two metallic naphthenates is used to achieve rapid drying of the surface and after-setting in depth. Calcium/lead naphthenate mixtures have been common, but since the 1970s lead has been increasingly superseded by zinc and zirconium. Lead, however, gives better after-setting at temperatures below 10ºC. Thus it is the metallic part which decides how the naphthenate functions. The naphthenate acid contributes by dissolving the substance in oils and other non-polar substances. Metallic soaps applied to oils have a gelling effect – the lubricant oil turns into lubricant grease. Naphthenates are also used in this way.

Use of naphthenates as siccatives is diminishing globally, partly due to a transition to other acids, above all 2-ethylhexane acid, which permits higher metallic content in the metallic soap, and also due to the substitution of water-based paints.

Copper and zinc naphthenates are also used to prevent microbial attacks on wood and textiles. These two naphthenates account for over 3/4 of use in Sweden, mostly as wood preservatives. Lead naphthenates are still being used in certain lubricants, in which the lead provides lubrication at high temperature (cf. lead lubrication of valve seats in petrol engines). 

Naphthenate

Paint and ink driers are metal carboxylates (mainly octoates and naphthenates) used in paint and ink manufacturing industries to enhance the film properties of the coating and accelerate the drying process.

They have the general formula of Me (RCOO) x, where Me is the metal, (RCOO) is the specific higher carboxylic acid group and x is the number of groups attached to the metal depending on its coordination number. The metal can be a heavy or an alkaline-earth metal and the carboxylic acid can be naphthenic, 2-ethyl hexanoic or C7-C11 acid.

BARIUM OCTOATE is improved to substitute toxic lead components in the paint systems. Barium octoate also shows a through drying of a coating and has good pigment wetting properties.

CALCIUM OCTOATE is an auxiliary drier. When used alone, calcium does not show a sufficient drying effect.In combination with active metal soaps calcium octoate gives much better results.

COBALT OCTOATE is the most active and most widely used drier metal. It catalyses the oxygen uptake, accelerates peroxide formation and effects mostly surface-drying. To prevent wrinkles in the film cobalt octoate is used in conjunction with auxiliary driers than can either the activity of cobalt (zinc octoate) or promote drying of the interior of the film (lead octoate). Cobalt also improves the hardening in baking alkyd-melamine systems.

LEAD OCTOATE is also an auxiliary drier. Lead octoate is used in combination with manganese, cobalt and calcium octoates.

MANGANESE OCTOATE is also a surface drier but is a little less active than cobalt. Manganese octoate catalyses the polymerisation in baking finishes and gives a better through-drying than cobalt. It is especially suitable for exterior coatings, enamels and baking finishes.

ZINC OCTOATE is also an auxiliary drier and produces a hard film when used in combination with cobalt octoate. Zinc driers mostly help the oxygen uptake by keeping the film 'open' thus retarding surface dry.

ZIRCONIUM OCTOATE is often applied a substitute for lead octoate.

OTHER OCTOATES We can offer a wide range of carboxylates including cerium, copper, Nickel and Sodium upon request.

Plastic Injection Molding

Plastic injection molding is the primary process for manufacturing plastic parts. Although the tooling is expensive, the cost per part is very low.  Complex geometries are possible and limited only to mold manufacturability.  Your computer monitor, mouse and keyboard are injection molded plastics.

Injection molding involves taking plastic in the form of pellets or granules and heating this material until a melt is obtained. Then the melt is forced into a split-die chamber/mold where it is allowed to "cool" into the desired shape. The mold is then opened and the part is ejected, at which time the cycle is repeated.

Design Considerations

Part design should include draft features (angled surfaces) to facilitate removal from the mold.  Depending surface length draft angles down to half a degree are reasonable. Typical draft angles should be about 1 to 2 degrees for part surfaces not exceeding 5 inches.  Dimensional tolerance specification will govern the part cost and manufacturability.  If you have a small region of the part that needs higher tolerances, say the location of a critical feature used for alignment.  DO NOT specify tight tolerance, instead design and plan for post molding processes such as machining using "assembly intent" fixturing.

Wall Thickness

Wall thickness for thin parts such as a soda bottle or ball point pen ink inserts are quite possible and economical. Thick wall sections are possible as well. Uneven wall thickness present challenges to the plastic molder manufacturer.  Designing your part with uniform walls and cross section will simplify manufacturing and costing.  At wall intersection or "tees" sinking will occur.  Thick walls cool slower and greater shrinking will occur.  Thin walls cool faster as thus, less shrinkage.

Radii and Corners

Maintain uniform wall thickness at corners.  External and internal radius should share the same center point.  External radii = internal radii + wall thickness. The minimum radii should not be less than 1/4 minimum wall thickness.  Design for radii to be 1/2 to 3/4 of the nominal wall thickness.  When significant stress is present, design in larger radius as larger radius distributes stress uniformly.

Ribs

Ribs should be 1/2 to 2/3 of the nominal wall thickness and less than 3 times thickness in height.  Taper of 1 deg. is typical.  Note: excess thickness promotes shrinkage.  Excess rib height combined with taper will produce thin sections requiring extra fill time at the mold.

Bosses

Diameter = (Outside Diameter) \ (Inside Diameter) = 2 to 3

Thickness = 1/2 to 2/3 nominal wall thickness

Gusset Height = 2/3 Height

Height = Fastener minimum requirements

Taper = 1 deg. all around

Diameter Ratio should be minimum ratio of 2. This will reduce risk of failure.

Weld (Part) lines 

Location should be considered by design and the molder.  Weld lines are formed at the mating of the flow fronts of the plastic during molding.  The weld line area is more susceptible to cracks and stress failure.

Surface Finish (micro inches) 64 or higher, depending on material, down to 7-16 is possible

mold

A

ACIS - A standard computer file format for exchanging CAD data, typically from AutoCAD programs.

A-Side - The mold half that mounts to the fixed side of the injection molding press, through which resin is injected into the part cavity via the sprue. Sometimes referred to as the cavity side of the mold, the A-side does not have ejector pins and for this reason it often produces the outside or cosmetic side of the part.

B

Barrel - The part of the molding press where resin is melted.

Bead blasting - Using abrasives in a pressurized air blast to create a surface texture on the part.

Bevel - See “chamfer”.

Blush - Cosmetic blemish at the point of injection in the finished part.

Boss - A cylindrical protrusion within a part, often designed to accept fasteners.

Bridge tool - A temporary or interim mold made for the purpose of making production parts until a high-volume production mold is ready.

B-Side - The mold half that mounts to the moving side of the injection molding press. Sometimes referred to as the core side of the mold, the B-side has ejector pins to push the part out of the open mold. An analysis of the part geometry determines the optimal part orientation to ensure that it will remain on the B-side when the mold is opened.

C

CAD - Short for “computer aided design”.

Cam - See “side action”.

Cavity - A concave feature on either side of the mold into which an opposing core enters when the mold is closed. The void between the cavity and core is where the resin solidifies and forms the part. Often the A-side of a mold is referred to as the cavity side, and in the case of a part like a drinking cup, the entire A-side will be a cavity.

Chamfer - Also known as a bevel, it is a flat truncated corner.

Clamp force - The force required to hold the mold shut so resin cannot escape during injection.

Contoured pins - Ejector pins with the ends shaped to match a sloping surface on the part.

Core - A convex feature on either side of the mold that will enter an opposing cavity when the mold is closed. The void between the cavity and core is where the resin solidifies and forms the part. Often the B-side of a mold is referred to as the core side, and in the case of a part like a drinking cup, the entire B-side will be a core.

Core-cavity - The design of a mold where the A-side forms the outside of the part and the B-side forms the inside. The advantage to this approach is that the part will shrink onto the B-side so it can be ejected, and if the inside and outside are drafted with equal and opposite draft the wall thickness will be constant.

Cycle time - The time it takes to make one part including the closing of the mold, the injection of the resin, the solidification of the part, the opening of the mold and the ejection of the part.

D

Direction of pull - Refers to the motion of a part surface relative to a mold.

Draft - The taper of features in the direction of pull. It allows deeper features to be produced in three-axis milling machines and it also helps parts release from the mold during ejection.

Drying of plastics - Many plastics absorb water and must be dried prior to injection molding to ensure good cosmetics and material characteristics.

Durometer - A measure of the hardness of a resin. It is measured on a numeric scale with numbers ranging from lower (i.e. softer) to higher (i.e. harder).

E

Edge gate - An injection method that uses a gate on the parting line of the mold. It typically leaves a vestige on the outside of the part and is sometimes referred to as a tab gate.

Ejection - The process of pushing a completed part out of a mold.

Ejector pins - Steel pins incorporated into the B-side of a mold that push out the plastic part.

End mill - A cutting tool that is used to machine a mold.

ESD - Stands for “electro static discharge”, an electrical effect that may necessitate shielding in some applications. Some special grades of plastic are electrically conductive or dissipative and help prevent ESD.

F

Family mold - A mold containing two or more different parts.

Flame retardant - A resin formulated to resist burning.

Flash - Excess plastic that flows into the parting line of the mold beyond the edges of a part and freezes to form a thin, sheet-like protrusion from the part.

Flow marks - Visible indications on the finished part that indicate the flow of plastic within the mold prior to solidification.

Food grade - Resins or mold release sprays that are approved for use in the manufacture of parts that will contact food in their application.

G

Gate - The location where the plastic enters the part. There is typically a visible vestige when the gate is removed.

GF - Stands for “glass filled”, it refers to a resin with glass fibers mixed into it. Glass filled resins are much stronger and more rigid than the corresponding unfilled resin, but also more brittle. Resins can also be filled with carbon fiber, stainless steel, etc. In general, filled resins can be very susceptible to warp.

Gusset - A triangular rib that reinforces areas such as a wall to a floor or a boss to a floor.

H

Hot tip gate - An injection molding method that uses a heated gate on the A-side of the part to eliminate the creation of any runner or sprue. The gate vestige will be a small sharp bump that can be trimmed if necessary.

I

IGES - Stands for “Initial Graphics Exchange Specification”. It is a common file format for exchanging CAD data.

Injection - The process of forcing melted resin into a mold.

J

Jetting - Flow marks caused by the resin entering a mold at high speed, typically occurring near a gate.

K

Knit lines - Visible indications in a finished part, formed by the intersection of two hot plastic fronts. They are always formed downstream of through - holes and between multiple gates. They are also known as weld lines.

L

Living hinge - Very thin section of plastic used to connect two parts and keep them together while allowing them to open and close. They require careful design and gate placement. A typical application would be the top and bottom of a box.

M

Medical grade - Resin that may be suitable for use in certain medical applications.

Metal-safe - A change to the part design that requires only the removal of metal to produce the desired geometry. Typically most important when a part design is changed after the mold has been manufactured, because then the mold can be modified rather than entirely re-machined. It is also commonly called "steel safe".

Mold release spray - A liquid applied to the mold as a spray to facilitate the ejection of parts from the B-side. It is typically used when the parts are difficult to eject because they are sticking to the mold.

Multi-cavity mold - A mold with multiple copies of the same part, typically used to reduce piece-part pricing for higher volume runs.

N

Nozzle - The tapered fitting on the end of the barrel of the injection molding press where the resin enters the sprue.

P

Packing - The practice of using increased pressure when injecting a part to force more plastic into the mold. This is often used to combat sink or fill problems, but also increases the likelihood of flash and may cause the part to stick in to the mold.

Parasolid - A file format for exchanging CAD data.

Parting line - The location where the pieces of a mold come together. Typically a thin line is created on the part here.

Post gate - An injection method that injects plastic through an ejector pin hole. This gating technique leaves a gate vestige on the B-side of the part where it can often be less visible for cosmetic purposes. There is often gate blush opposite a post gate.

Press - The injection molding machine that makes the plastic parts. It holds the mold closed, melts the resin, injects it into the mold, opens the mold and ejects the part.

Process - The injection molding environment consisting of input variables such as temperature, pressure, injection rates and time that are controlled to fill the mold while optimizing the tradeoffs between cosmetics and dimensional accuracy.

R

Radiused - An edge or vertex that has been rounded.

Recess - An indentation in the plastic part caused by the impact of the ejector pins.

Reinforced resin - Refers to base resins with fillers added for strength. They are particularly susceptible to warp because the fiber orientation tends to follow flow lines, resulting in asymmetric stresses. Typically these resins are harder and stronger but also more brittle (i.e. less tough).

Resin - Synonymous with “plastic” as far as injection molding is concerned.

Rib - A reinforcing member of a molded part.

Runner - A channel machined into the mold that directs the resin from sprue to the gate.

S

Screw - The mechanical feature inside the barrel that forces the resin out the nozzle. Shear - The force between layers of resin as they slide against each other or the surface of the mold. The resulting friction causes some heating of the resin.

Short shot - A part that wasn't completely filled with resin, causing short or missing features.

Shrink - The change in size of the part during solidification typically anticipated based on published material property data and built into the mold design prior to machining.

Shutoff - The surfaces where the A-side and B-side of the mold contact. The shutoff meets the part at the parting line.

Side action - A sliding cam arrangement within the mold that allows for the molding of parts with undercuts. The undercut-creating mold face is held in place during the injection process and then slides out of the way prior to ejection.

Sink - Undesired depressions in the surface of a part that are caused by the shrinking of resin as it solidifies. Sink is most common in thick sections of a part.

Splay - Discolored visible streaks in the part, typically caused by moisture in the resin.

Sprue - The route the resin takes from the point where it enters the mold until it reaches the runner(s). When solidified, it remains attached to the part via one or more runners and is typically removed in finishing.

Steel safe - See “metal-safe”.

STEP - Stands for "Standard for the Exchange of Product Model Data”. It is a common format for exchanging CAD data.

Sticking - A problem during the ejection phase of molding, where a part becomes lodged in one or the other half of the mold, making removal difficult. This is a common issue when the part is not designed with sufficient draft.

STL - Originally stood for “Stereo Lithography”. It is a common format for transmitting CAD data to rapid prototyping machines and is not suitable for rapid injection molding.

Straight pull mold - A mold without side actions. It is less expensive than a comparable mold with side actions.

T

Tab gate - See “edge gate”.

Telescoping shutoff - An area within a mold where metal slides along metal, usually creating a hole in the part. A three degree draft angle is required on any related part surfaces.Texture - A surface treatment applied to the mold to create texture on the parts.

Tunnel gate - An injection method that uses a small gate located off the parting line in one of the mold halves. It leaves a vestige a short distance from the parting line of the part.

U

Undercut - A portion of the part geometry that would prevent the part from being ejected from a straight-pull mold without a portion of the mold passing through (and destroying) the part. The simplest example of an undercut feature on a part would be a through-hole aligned perpendicular to the direction of part ejection.

V

Vents - A very small (e.g. 0.001” – 0.005”) opening in the mold cavity, typically at the shutoff surface or via an ejector pin tunnel, that is used to let air escape from a mold while the resin is injected.

Vestige - A visible mark created by the manual process of finishing parts when the gate is trimmed. Ejector pins also may leave a vestige where they impact the part (also see “recess”).

W

Warp - The curving or bending of parts that typically occurs after ejection as the part cools. Warp is often caused by glass filled resins.

Weld lines - See “knit lines”.

Wireframe - A type of CAD model consisting only of lines and curves, in 2D or 3D. Wirefame models are not suitable for rapid injection molding.

what is a mold?

A mold used to produce plastic parts is a metal form consisting of a core and a cavity for each part. The core forms the inner shape of the part, while the cavity forms the outer shape of the part. The space between the core and the cavity is where the melted material flows (in injection molding) or the heated, softened material is pressed (as in pressure forming or thermo-forming) to form the plastic part. Molds range in size from single cavity to upwards of 200 cavities, depending on the size of the component and the number of parts required. A car bumper mold, for example, is generally only one cavity. The type of mold and runner system selected depends on the design and complexity of the part to be produced.



A mold can be a complex piece of equipment that makes very complex components, and can even allow other functions to be performed inside the mold cavity such as decorating the part, assembling the part, and other functions to save time and money on secondary operations. A mold can also be a simple piece of equipment that molds simple parts. The cost of the mold is determined by the complexity, size, process type being used (i.e. blow molding, injection molding, thermoforming/pressure forming), and design requirements of the plastic component being molded.

Traditionally, molds have been expensive to manufacture. They were usually only used in mass production where thousands of parts were being produced. Molds are typically constructed from hardened steel, pre-hardened steel, aluminum, and/or beryllium-copper alloy.

Molds can be manufactured by standard machining or by using electrical discharge machining processes.

Standard Machining, in its conventional form, has historically been the method of building injection molds. With technological development, CNC machining became the predominant means of making more complex molds with more accurate mold details in less time than traditional methods.

The electrical discharge machining (EDM) or spark erosion process has become widely used in mold making. As well as allowing the formation of shapes which are difficult to machine, the process allows pre-hardened molds to be shaped so that no heat treatment is required. Changes to a hardened mold by conventional drilling and milling normally require annealing to soften the steel, followed by heat treatment to harden it again. EDM is a simple process in which a shaped electrode, usually made of copper or graphite, is very slowly lowered onto the mold surface (over a period of many hours), which is immersed in paraffin oil. A voltage applied between tool and mold causes spark erosion of the mold surface in the inverse shape of the electrode.

Plastic molds

Arete Mold has over 20 years of experience in designing and manufacturing a wide variety of plastic molds. Arete offers customized solutions with advanced technology and competitive prices.

Arete's strength comes from constant technical innovation which enables us to satisfy the demanding needs of customers worldwide. Our customers cover nearly all aspects of the plastic industry including automotive, home appliance, houseware, and electronics, etc..

We use quality materials and a strictly controlled production process for each mold we manufacture. From concept design and project management through to the finished product, we utilize the latest design technology to manufacture high quality molds. Each project is handled uniquely and is customized according to your specific requirements.

Arete offers a full range of services to satisfy all your needs, including mold design, mold tooling, hardware stamping, and product assembly, etc.. Our customers have been satisfied with our rapid delivery times and attentive after-sales services over the past 20 years.

With the emphasis on precision and quality, we work closely with each customer to find out the best possible solutions. If you need a mold to meet high production requirements, please count on Arete to become your competitive advantage.

Automatically switch

Automatically switchfrom the following three main parts:

(1) sensory components. Responsible for receiving circuit in the case of the anomaly or the operator, relay protection system signals through the transmission of action components to enable the implementation of components. Such as over-current or undervoltage release, such as release.

(2) transmission components. Responsible for power transmission, transformation, including the operation of institutions, transmission, free release agencies, such as the spindle.

(3) the implementation components. Automatically switch contact and interrupter system, mainly responsible for the access circuit and breaking the task.

The left photo shows the structure of the general principle of automatic switch which is in working condition. The three main contact and the locking rod through the transmission to keep closed, locking can rotate around the axis. When the circuit is in normal operation, the over-current release of the electromagnetic coil string although in the main loop, but can not be generated by suction so that armature movement, and only when the circuit short-circuit or overload occurs, the armature when the contract was rapid impact absorption lever to lock release, the main contact was the rapid opening of spring breaking the main circuit. In contrast, in normal operation, the undervoltage release coil electromagnetic because it is a parallel in the main circuit, the required voltage range so that the normal pull-keeper, at the same time to overcome the spring tension. When the circuit failure, low voltage (usually 70% of rated voltage or less) to reduce suction, armature by spring open and hit the lever to release locking, the main role of contact in the spring rapidly breaking the circuit.

the structure and principle of Automatically switches

1 the main contact; 2 transmission pole; 3 Lock; 4 axis;

5 lever; 6 Spring; 7 over-current release;

8 under-voltage release; 9 armature; 10 spring;

Case in a number of small-capacity automatic switch,exception with the short-circuit protection, also equipped with a double metal sheets which be made of release, when the circuit overload occurs, the dual-metal bending, open the lock, breaking contact circuit.

Types of Electric Switches

Cam switches have a plastic disk (cam) over which contoured surface a mechanical follower moves, controlling the contacts. The cam is attached to and rotated by a handle shaft.

Double pole double throw (DPDT) switches open or close the connections of two conductors to a pair of separate circuits. DPDT switches, which usually have six terminals, can be set to maintain contact, alternate contact or have momentary contact.

Double pole single throw (DPST) switches open or close the connection of a pair of circuit conductors in a single circuit. DPST switches usually have four terminals.

Dual inline package (DIP) switches are a set of small-sized ON-OFF switches. DIP switches are used in place of jumpers and in such electronics as garage door openers, personal computers and paintball marker electro-chips.

Enabling switches are similar to safety switches , except they are manually operated. Enabling switches are designed to protect workers in more hazardous environments in which there is heavy machinery.

Key lock switches are activated by use of a fitting key. The key is turned to one of several positions, triggering the switch.

Lever switches are activated by turning a lever that is connected to a pivot point. Lever switches typically have three positions.

Limit switches are utilized in monitoring and for the control of machinery and industrial equipment. Limit switches come in many different sizes and configurations.

Maintained switches stay in the selected position when the handle is released.

Miniature switches are used in applications that require compact mechanisms, such as handheld equipment.

Multiple limit switches are used for the positioning and control of industrial equipment and machinery.

Pressure switches convert pressure changes to electrical functions.

Pushbutton switches are so called due to their activation method, which is usually in the form of a plunger that, when pushed down, opens or closes the switch. The configurations of these mechanical switches can be single-pole single-throw (SPST), single-pole double-throw (SPDT), double-pole single throw (DPST), double-pole double throw (DPDT) or solid state.

Reed switches feature two contact blades, called ferromagnetic reeds, which are encapsulated in glass. The reeds close when exposed to a magnet.

Rocker switches are electric switches that are activated by rocking the switch to one side.

Rope pull switches are triggered when there is tension in the safety cable. Rope pull switches provide safety and monitoring contacts in the printing, food processing and pharmaceutical industries.

Rotary switches have contacts that are arranged in a full or partial circle, which means the mechanism that selects the contact must be turned. Rotary switches, which may be manual or automatic, are used in such applications as automobile distributions or ignition switches.

Safety switches feature integrated actuators, which serve to protect both equipment and personnel. This is done by monitoring the positions of movable components.

Single pole double throw (SPDT) switches, also referred to as "three-way switches," open or close the connection of one conductor with one of two other conductors. SPDT switches often have three terminals and are sometimes used in pairs.

Single pole single throw (SPST) switches, also called a "single-pole switches," open or close the connection of one conductor in a single circuit. SPST switches usually have two terminals.

Snap action switches are designed to very quickly move their contacts from one location to another. Mouse buttons and appliance settings use such switches.

Toggle switches have only two positions. Light switches and the caps lock key on a computer keyboard are examples of toggle switch applications.

Description of rocker switches

A rocker switch is an on/off switch that rocks (rather than trips) when pressed, which means one side of the switch is raised while the other side is depressed much like a rocking horse rocks back and forth. Designed for use in low voltage and current level circuits, rocker switches are available in a variety of sizes, ratings, colors, and termination types.

A rocker switch may be marked with a circle (for "on") and a horizontal dash or line (for "off") on the other to let the user known if the device is on or off. They may also be lighted to indicate on or off status.

A rocker switch with independent circuitry can have a light activated on the face of the switch in both the on and off positions, which allows the switch to be found easily in the dark. With dependent circuitry, the light is activated only when the switch is on.

Rocker switches are commonly used in surge protectors, display monitors, computer power supplies, and automotives. Although they are found most often in portable appliances and electronics, rocker switches are also utilized in the communications, transportation, medical, and automobile industries.

Ten tips for the security about the electricity

1:Ask a professioal to set the electrocircuit

2:Choose a good electrical wire.

3:Choose the micro switches best.

4:Set a lighting rod on your housetop.

5:Don't use any electric equipment when lightning.

6:Please sure you won't closed to the wall when raining.

7:Don't touch any conductor when raining.

8:Stay at home and don't go out when lightning.

9:No conductor in your pocket.

10:Don't open the electrical wire by yourself.

Industrial Pressure Switches GLOSSARY

1. Absolute Pressure

The difference between zero pressure (a perfect vacuum) and some known pressure.

2. Accuracy (Repeatability)

The maximum allowable set-point deviation of a single pressure switch under one given set of environmental and operational conditions.

3. Actuation Point (Set Point)

The point at which the switch is actuated to either open or close the electrical circuit, depending on how the switch is wired.

4. Ambient Pressure

Adjacent (not necessarily atmospheric) pressure immediately surrounding the switch .

5. Ambient Temperature

Adjacent (not necessarily atmospheric) temperature immediately surrounding the switch .

6. Atmospheric Pressure

The actual weight of the earth's atmosphere at a given locale and altitude. Atmospheric pressure at sea level is approximately 14.7 psia or 30 inches of mercury.

7. Deadband (Differential / Hysteresis)

The difference between the actuation point and the deactuation point.

8. Deactuation Point

Once the switch is actuated (See Actuation Point), the point at which the switch then changes state (open or closed depending on wiring) to return it to its initial state.

9. Differential

See Deadband.

10. Double-Pole Double-Throw (DPDT)

switch es which make and break two separate circuits. This circuit provides a normally open and normally closed contact for each pole.

11. Differential Pressure

The differential between two independent pressures.

12. Electrical switch ing Element

Opens or closes an electrical circuit as a result of the movement it receives from the pressure sensing element.

13. Explosion-Proof switch

A UL listed switch capable of withstanding an internal explosion of a specified gas without igniting surrounding gases.

14. Factory Set

A pressure switch design that can be set only at the factory to customer's requirements.

15. Field Adjustable

A pressure switch design that provides for adjustment of set points in the field.

16. Hermetically Sealed

An enclosure completely sealed from escaping or entry of gases or liquids. All joints are soldered or welded to insure sealing integrity. Hermetically sealed electrical assemblies are metal to metal or glass to metal infusion.

17. Hysteresis

See Deadband.

18. Maximum System Pressure

Maximum continuous pressure which may be applied to any switch without causing permanent degradation.

19. Normally Closed (N/C)

Provide a normally closed circuit when actuator is in free position.

20. Normally Open (N/O)

Provide a normally open circuit when actuator is in free position.

21. Pressure Sensing Element

The portion of the pressure switch that is in contact with the media and moves as a result of a change in pressure of the media.

22. Pressure switch

An electromechanical device that upon the increase or decrease of pressure, opens or closes an electrical switch ing element at a predetermined set point.

23. Proof Pressure

Maximum momentary pressure including surges, which may be applied to any switch without causing permanent degradation.

24. Rise Rate or Ramp Rate

The rate at which the pressure will increase in a unit of time.

25. Set Point

See Actuation Point.

26. Single Pole Single Throw (SPST)

Continuity of circuit is only possible through one leg of circuit.

27. Single Pole Double Throw (SPDT)

Continuity of circuit is possible through either/both legs of circuit but not at the same time.

28. Surge Pressure

A transient pressure varying in amplitude, frequency, and duration.

29. Wetted Parts

Components of a pressure switch that are directly exposed to the media.

switch

In electronics, a switch is an electrical component which can break an electrical circuit, interrupting the current or diverting it from one conductor to another. The most familiar form of switch is a manually operated electromechanical device with one or more sets of electrical contacts. Each set of contacts can be in one of two states: either 'closed' meaning the contacts are touching and electricity can flow between them, or 'open', meaning the contacts are separated and nonconducting.

In the simplest case, a switch has two pieces of metal called contacts that touch to make a circuit, and separate to break the circuit. The contact material is chosen for its resistance to corrosion, because most metals form insulating oxides that would prevent the switch from working. Contact materials are also chosen on the basis of electrical conductivity, hardness (resistance to abrasive wear), mechanical strength, low cost and low toxicity.

Sometimes the contacts are plated with noble metals. They may be designed to wipe against each other to clean off any contamination. Nonmetallic conductors, such as conductive plastic, are sometimes used.

The moving part that applies the operating force to the contacts is called the actuator, and may be a toggle or dolly, a rocker, a push-button or any type of mechanical linkage.

Contact arrangements

A pair of contacts is said to be 'closed' when there is no space between them, allowing electricity to flow from one to the other. When the contacts are separated by an insulating air gap, an air space, they are said to be 'open', and no electricity can flow at typical voltages.

switch es can be and are classified according to the arrangement of their contacts in electronics fields— but electricians in the electrical wiring service business and their electrical supplier industries use different nomenclature, such as "one-way", "two-way", "three-way" and "four-way" switch es—which have different meanings in North American and British cultural regions as is delineated in the table below.

Some contacts are normally open (Abbreviated "n.o." or "no") until closed by operation of the switch , while others are normally closed ("n.c. or "nc") and opened by the switch action, where the abbreviations given are commonly used on electronics diagrams for clarity of operation in assembly, analysis or troubleshooting. They serve to synchronize meaning with possible mistakes in wiring assembly, where wiring part of switch one way and part another (usually opposite) way will pretty much guarantee things won't work as designed.

A switch with both types of contact, that can switch on a circuit in one position & can switch another circuit on in other position, is called a changeover switch or "make-before-break" switch contact, whereas most switch es have a spring loaded action which momentarily disconnect the load and so are "break-before-make" types by contrast— which type is used could be important, if for example, the switch selects two different power sources instead of switch ing circuit loads, or the circuit load will not and cannot tolerate any interruption in applied power.

The terms pole and throw are also used to describe switch contact variations. A pole is a set of contacts, the switch 's electrical terminals that are connected to and belong to a single circuit, usually a load. A throw is one of two or more positions (the nomenclature is also applied to rotary switch es, which can have many 'throw' positions) that the switch can adopt, which normally, but not always correspond to the number positions the switch handle or rotor can take when connecting between the common lead of the switch and a pole or poles. A throw position which connects no terminals (poles) has a mis-match between positions and positions which connect terminals, but are quite useful to turn things "Off" or for example, alternatively select between two scaled modes of operation. (e.g. Bright illumination, moderate illumination, no illumination.)

These terms give rise to abbreviations for the types of switch which are used in the electronics industry such as "single-pole, single-throw" (SPST) (the simplest type, "on or off") or "single-pole, double-throw" (SPDT), connecting either of two terminals to the common terminal. In electrical power wiring (i.e. House and building wiring by electricians) names generally involving the suffixed word "-way" are used; however, these terms differ between British and American English and the terms two way and three way are used in both with different meanings.

Micro switches

In electronics, the micro switches is an electrical component which can break an electrical circuit, interrupting the current or diverting it from one conductor to another. The most familiar form of the micro switches is a manually operated electromechanical device with one or more sets of electrical contacts. Each set of contacts can be in one of two states: either 'closed' meaning the contacts are touching and electricity can flow between them, or 'open', meaning the contacts are separated and nonconducting.

Since the advent of digital logic in the 1950s, the term has spread to a variety of digital active devices such as transistors and logic gates whose function is to change their output state between two logic levels or connect different signal lines, and even computers, network switches, whose function is to provide connections between different ports in a computer network. The term 'switched' is also applied to telecommunications networks, and signifies a network that is circuit switched, providing dedicated circuits for communication between end nodes, such as the public switched telephone network. The common feature of all these usages is they refer to devices that control a binary state: they are either on or off, closed or open, connected or not connected.

RadioShack recalls electrical switches

WASHINGTON, April 3 (UPI) -- The U.S. Consumer Product Safety Commission announced a voluntary recall of RadioShack electrical micro switches due to faulty installation instructions.

The wiring instructions that come with the illuminated round rocker switches, catalog number 275-0021 with date codes of 01P09 or January 2009 or early, are incorrect, specifically a diagram on the package, the Commission said.

About 18,000 of the switches were sold nationwide from June 2008 and January 2009 for about $4.

Consumers were advised to contact RadioShack Corp. (NYSE:RSH) of Fort Worth, Texas, for correct installation instructions.

Permanent Magnets from Stanford Magnets Company

Our manufacturer has been involved in research, development and manufacturing of permanent magnets since the middle of 1980. Now, we supply various rare earth permanent magnets products to our customers in various fields, such as NMR (Nuclear Magnetic Resonance), loud speakers and mechanical devices, in large production quantities at VERY competitive pricing. We supply rare earth permanent magnetic materials in powder form or in sintered as well as polymer-bonded magnet form. We also supply other permanent magnet materials including Alnico, Ceramic (Ferrite) and Flexible magnet materials. We specialize in manufacturing permanent magnets according to customers' requirements in terms of composition, magnetic characteristics, shape, and size. If you have any needs for permanent magnetic products, please contact us. You will be very happy to have us as your vendor, supplying you with high quality products at unbeatable prices.

Micro switch history

Micro switch ? technology has launched most sensing and switching products Sensing and Control produces. View early versions of micro switch devices, in addition to the legacy of micro switch products.

1942

In 1943, the V3 switch was named to represent Victory in Europe, Victory in Asia, and a Victory for micro switch products. The first class postage stamp at the time was an eagle with outspread wings in the form of a “V”. The cost was 3 cents. The V3 and postage size stamp of the switch all seemed to go together, so V3 it became.

1944

The development of the EN micro switch line was just in time to catch the front end of the jet engine age. Landing gear switches had become a particular problem since available switches filled with water. It was necessary in many cases to drill holes to allow water to drain out. The excellent sealed features of the switch, together with its size, operating features and circuitry, were just what the aircraft industry was looking for. The EN was soon established as Military Standard.

1951

The need for attachment of lead wires directly to the switch was met by designing and providing the E and V die cast switch enclosures. This enclosed switch became one of the most popular micro switch product lines, sold year after year in volume for literally millions of applications. The enclosures started out as zinc die castings which were changed to aluminum during WWII for weight saving in aircraft applications. This family of switches became known as the “die cast” line, which has persisted as part of micro switch terminology for years.


1953

Almost as soon as the basic switch was put into use, people began to find ways to use it as a pushbutton switch. Through the years, ’s micro switch push button line has been used for military aircraft (originally advertised as a unit that would allow aircraft to use wing and tail lights to signal to ground stations using Morse Code), military tanks, and firing switches for nuclear warhead torpedoes on submarines.


1955

A development in ’s Solid State Research Center in Minneapolis led to the development of “Hall” micro switch components, named after the phenomena known as the Hall Effect. Researchers discovered that when an integrated circuit chip was moved through a magnetic field (or vice versa), a minute electrical current would be generated. This development led to the introduction of keyboard pushbutton units for the first IBM? computers, technology predecessor to the keyboards we use today.


1956

Experience with unsealed switches on aircraft during WWII pointed to the need for a hermetically sealed micro switch design. Rapid ascent and descent of aircraft from humid ground conditions to cold flight conditions often caused switch malfunction which was traced to icing of contacts. A glass-to-metal seal was conceived, and the new technology quickly became widely used, and is still popular to this day.

1957

In 1937, the Explosion Proof micro switch family of products was introduced, ushering in a safer working environment in industrial settings. The switch was engineered to ensure that volatile gases that entered the switch and exploded would not ignite gases outside the switch enclosure. The configuration and size of the switches made it the smallest explosion proof switch on the market, a position it has maintained since its existence.

1971

pioneered the designs for basic, miniature, subminiature, heavy-duty and limit switches. These core designs are the standard footprint for most electromechanical switches manufactured by switch providers globally today.

1972

Sensing and Control maintains a global manufacturing and service footprint, with customer service and factory locations in North America, Europe and Asia. micro switch products are currently made in Freeport, IL, Galena, IL, Juarez, Mexico, and Newhouse, Scotland.

micro switch

Honeywell's micro switches EX Series Hazardous Location line of switch
products received the International Electrotechnical Commission's Certification to Standards relating to Equipment for use in Explosive Atmospheres (IECEx). With this international certification, Honeywell's global customers can be assured their explosion-proof switch meet the IEC's high standards for equipment used in explosive atmospheres.



In addition to IECEx certification, the EX family of products currently holds North American UL/CSA and European ATEX approvals. With this certification, manufacturers can specify one Honeywell micro switches
EX Series switch for a machine that may potentially be used in Europe, Asia, or North America.



"Now that we have this certification, our customers can apply our products almost anywhere in the world and meet ever-increasing levels of safety regulations," said Brad Kautzer, vice president and general manager of the electromechanical line of business for Honeywell Sensing and Control.



"Honeywell offers a wide range of differentiated solutions to meet virtually any application requirement."

Swedes Develop Netbook Kill Switch

The problem: You are a telco, and you give away netbooks in order to lock customers into lengthy 3G internet contracts. The customer does a runner and stops paying his bills. With a cellphone, simply cutting the service from afar would make the handset useless. But with a netbook? The customer still has a fully working computer.
The solution: Fit a kill switch that can disable the netbook from afar. This is exactly what Ericsson has done, and it even has a catchy name for the tech: "We call it a 'kill pill," Ericsson VP Mats Norin told the Associated Press.
The mobile broadband card, called the F3607gw, has other features, such as low power consumption and wake-on-wireless capability, but its the remote control that is the most interesting. By sending an SMS to the unit, the card speaks to Intel's ATT (Anti-Theft Technology) inside the machine. This not only locks down the hard drive but the actual computer itself. Even swapping in a new drive wouldn't wake the computer from its deathly slumber.
Morally, we're confused on this one. When you sign a contract, you are agreeing to honor an agreement. Break it and the injured party has a right to redress, and to repossess its property. On the other hand, handing life or death control of our equipment over to somebody else is always a chilling thought. Our advice? Buy your own machine and stick a 3G USB dongle in the side. But then, we're control freaks. In fact, give us the handle of the kill switch so we disable our machines if they are stolen.

Three fingers been cut

Yesterday afternoon, a chinese working man, when he cleared the meat grinder machine, his hand was swallowing into it and three fingers been truncated, the doctors said that can only cut his toe for replantation.

Mr GU is 32-year-old this year, and work at a supermarket which about fresh meat. Yesterday 11:30, He looked many residues in the grinder, so he clean up it, but he does not turn off the machine switch. When he clear it with his left hand, suddenly his hand was been swallow. Other workers heard the scream, immediately unplug the power switch, too late, His hand was bloody.Other peoples help him out it, the index finger, middle finger and ring finger all be cut off and be crushed. Others sent him to the Provincial People's Hospital and take the fingers also. When the doctor prepare to do a finger replantation surgery, found that three fingers are broken badly. So the doctor only can cut one toe for replantation which ensure that his left hand have the general function.

How to choose a switch

Although the appliance of switches socket does not like other big things, but relations to the security in every home everyday. Now, how to choose the switch socket? It's very important!

Switches handle: In order to ensure the connect is reliable, low contact resistance, generally the good switch’s spring is hardly, and common switch is very soft, and even happen that the switches handle often parked in the middle situation, pose a security risk.

Fluorescence switches: general have the fluorescence switches and power LED-based (such as neon bubble), first switches the prices is more lower, but the phosphor in the light will soon out of energy when disappearance of the outside world! Cannot play the role of fluorescence.

Copper: when choose the copper, it must require that the structure design is very reasonable, also must ensure that the copper is thick.

Hello,everyone!

Hello,everyone!

Welcome to my blog!

This blog is about switches. If you have any question about the Switches , you can ask me,our website is http://www.american-switches.com/, you can E-mail to me: jimmy.wang@oceania-inc.com.

About American Switches

Originally established in 1991,American Switches is now recognized as a global manufacturer of quality appliance Switches and indicator lights.

American Switchesoffers a wide variety of Switches styles including push-button, rocker, air pressure and micro switches. The majority of them are granted by international approvals, such as UL, TUV, CE, CB and EK. Our customers and their end users worldwide rely on our products for applications that are used in diversified industries including household appliances, instrumentation, industrial automation and others.

American Switchesobtained ISO 9001 certification in 1999. From raw materials to finished products, through design and production, we control all the production stages. Our engineers focus on innovative technologies and strive to provide optimum solutions for all of your application requirements.

American Switcheswill continue to provide outstanding services by providing quality products at competitive prices and being responsive to market demands.

American switches

American Switches is your premier supplier of push-button switches, rocker switches, air pressure switches, micro switches and indicator lights. We offer exceptional quality and service at competitive prices.

The majority of them are granted by international approvals, such as UL, TUV, CE, CB and EK. Our customers and their end users worldwide rely on our products for applications that are used in diversified industries including household appliances, instrumentation, industrial automation and others.