Computer Numerical Control

what is a cnc limit switch?

Two kinds of switches.
1.) Normally Open.
2.) Normally Closed.
There are many different kinds of limit switch makes, some are electric and others are mechanical you can even find wireless limiting switches and Optical Limiting switches. So why is it called a limit switch? Simply because it stops the movement of the axis when interacted with, really a limit switch can be as simple as a two wire switch that completes or breaks a circuit when pressed. When continuity exists load is supplied to the breakout board and the computer program stops the motion of the steppers, or in some cases when the circuit if broken the supply voltage is removed from the driver circuit, after the interaction the CAM program will either continue or await the operators attention.

What is a switch?

 A switch can be used to complete a circuit or break a circuit, you see them in your home and in everyday devices generally never thought of. They work when physical contact is made between two points of one wire completing or breaking a circuit.

A switch is used in Computer Numeric Control for a number of reasons and in many forms, some use infrared, or for some applications proximity censors maybe used. Generally the limit switch is used for determining the location of the material loaded, finding spinal and tooling location, and where the bed is. The limit switches act as a set of eyes of for the spinal.

What is a mechanical limit switch?

Mechanical limit switches offer very high precision due to the fact that physical contact is made between two points of one wire completing a circuit when pressed. It operates in real time. Although one drawback of the mechanical limiting switch, as the switch gets older parts start to wear so completing a circuit or breaking a circuit may become problematic, another drawback being if the environment is extreamly dusty, the dust may also cause problems.

"Mechanical limit switches are contact sensors widely used for detecting the presence or position of objects in industrial environments"

What is an electrical limit switch?

An electrical limit switch can be seen as an Optical switch, or infrared switch. The optical switch works by sending pulses very fast between two points, if that current is interupted the Micro-Processor and/ or CAM program will recognise the difference and stop the machine. No moving parts exist, so wear is no concern, they are also very reliable.

What is an Open Switch and what is a Closed Switch?

An open switch is not conducting; a closed switch is conducting.

What is a DIP switch

A DIP switch is short for "dual in-line package switch" because DIP is short for "dual in-line package" it is used in electronics to turn on or off certain circuit routs. more information can be found on the wikipedia website

What is a sensor?

"A device that responds to a physical stimulus (as heat, light, sound, pressure, magnetism, or a particular motion) and transmits a resulting impulse (as for measurement or operating a control) "

Here are the sensors used today?

Acoustic-(sound, vibration) Automotive-(transportation) Chemical, Electric-(current, electric potential, magnetic, radio) Environment-(weather, moisture, humidity) Flow-(fluid velocity) Ionising-(radiation, subatomic particles) Navigation-(instruments) Position-(angle, displacement, distance, speed, acceleration) Optical-(light, imaging, photon) Pressure, Force-(density, level), Thermal (heat, temperature), Proximity-(presence)

A sensor can be used in place of a switch, they are great for interacting with the world around us.

A good sensor obeys the following rules: