Tapered Roller Coil Spring Heating Device

The patent replaces the combustion heating furnace (mechanical/chemical heating system) with an electric induction heating system. The induction heating coil generates electromagnetic fields that induce eddy currents in the coil spring, heating it to 980°C or higher without direct contact with flames or hot gases. This substitution enables automated continuous heating while preventing decarburization, as the induction heating occurs in a controlled electromagnetic field rather than an oxidizing atmospheric environment.

The electric induction heating system creates an inert heating environment where the coil spring is heated by electromagnetic induction without exposure to oxidizing atmospheres. The heating coil generates eddy currents within the spring material itself, producing heat internally without requiring contact with combustion gases or hot air that would cause surface decarburization. This inert heating method allows the entire surface area to be heated uniformly without carbon loss.

The patent replaces parallel cylindrical rollers with tapered rollers that have asymmetric geometry. The rollers are tapered such that the diameter varies along the axial direction, creating a conical surface. This asymmetric shape allows the rollers to grip the coil spring effectively while rotating it, preventing the spring from popping out in the rotational direction. The tapered geometry provides radial inward force components that secure the spring during rotation and heating.

The tapered rollers act as intermediaries between the conveyor system and the coil spring. Instead of directly using simple parallel rollers that fail to secure the spring, the tapered rollers provide a transitional gripping mechanism. Their conical surfaces contact the spring at multiple points, distributing the gripping force and preventing ejection while allowing rotation. This intermediary tapered roller design bridges the gap between simple parallel roller structures and the need for reliable spring retention.

The patent implements continuous heating by maintaining constant rotational motion of the tapered rollers while the coil spring passes through the induction heating zone. The continuous rotation ensures that all surfaces of the spring are uniformly exposed to the electromagnetic field over time. The conveyor system provides continuous linear motion, and the combination with continuous roller rotation ensures uniform heating throughout the entire spring structure, preventing localized overheating or cold spots even at high processing speeds.

The patent uses dynamic rotation of the tapered rollers to achieve uniform heating. Instead of a static positioning system, the rollers continuously rotate the spring during heating. This dynamic rotation ensures that all surfaces of the coil spring are uniformly exposed to the induction heating coil's electromagnetic field. The rotational speed can be optimized to match the linear conveyor speed, ensuring that the spring spends equal time in each angular position within the heating zone, thereby achieving uniform heating distribution even at high productivity rates.