Diagonal coil springs are widely used in many fields, including:

1. Electrical equipment: Switches, vibrators, automatic shut-off components, etc. in electrical equipment require coil springs. For example, the timer switch of an alarm clock and the volume control of a television are typical applications of coil springs.

2. Mechanical equipment: Diagonal coil springs are also widely used in mechanical equipment, such as safety valves, valve components for various pumps, and hydraulic valves. In these devices, coil springs can be used to control liquid flow and pressure release.

3. Instrument manufacturing: Diagonal coil springs are also important components in instrument manufacturing, such as string instruments, reed instruments, etc. Diagonal coil springs can generate resonance and sound in these instruments.

4. Biomedical field: Oblique coil springs also have applications in the biomedical field, such as intraosseous switches, spinal fusion devices, etc. These devices require the use of coil springs for mechanical fixation and sealing.

In summary, helical coil springs have many unique performance and application advantages, such as lightweight, high precision, corrosion resistance, wear resistance, etc., and have therefore been widely used in many fields. With the continuous development of technology, the application fields of helical coil springs will continue to expand.