Definition

1. Noun:
   • A contact arm is a mechanical component, specifically a conducting arm that rotates over a series of fixed electrical contacts. It is designed to make an electrical connection by coming to rest on a specific outlet or contact point.

Usage

• The term contact arm is used primarily in technical and engineering contexts, especially when describing parts of electrical switches, relays, potentiometers, or ignition systems (e.g., in a distributor).

Examples

• Noun:
  • The technician adjusted the contact arm to ensure proper ignition timing.
  • In this variable resistor, the contact arm slides across a resistive strip to change the output voltage.

Advanced Usage

• "Wiper arm": In many contexts, especially in potentiometers or rheostats, a contact arm is also called a or , as it "wipes" across the contacts.
  • The potentiometer's output is controlled by the position of its contact arm (wiper).

Variants and Related Words

• Wiper (arm) (n): A synonym often used in electronics for a moving contact that slides over a fixed resistive element.
• Rotor arm (n): A specific type of contact arm found in the distributor of some internal combustion engines, which rotates to distribute high voltage to each spark plug.

Synonyms

• Wiper
• Moving contact
• Slider

Notes

• The reference context mentions "cần vít búa (vít lửa)," which is the Vietnamese term for a or in a traditional ignition system. This is a specific application of a contact arm.

Noun

1. contact consisting of a conducting arm that rotates over a series of fixed contacts and comes to rest on an outlet