Automated Lead Forming Equipment for Varistor Sleeve Heat-Shrink Forming Machine

Project scope

We designed a vertical electronics component sleeve forming machine for bulk varistors and discharge tubes. The machine combines vibratory bowl feeding for bulk varistors, manual sleeve-roll loading, manipulator handling, lead correction, lead cutting, rotary clamping, sleeve insertion, hot-air heat shrinking, cooling and finished-part unloading. That makes the scope an Automated Lead Forming Equipment application for varistor sleeve feeding, heat shrinking, cooling and unloading.

The equipment is built as a single-machine station. Operators load bulk varistors into the vibratory bowl and place the sleeve roll onto the support position; the machine then handles the component transfer, sleeve application and heat-shrink forming sequence.

Integrating sleeve forming after lead preparation

The process has to prepare the component before sleeving. The four-station manipulator route includes clamping, correction, lead cutting and transfer to the clamping position. Only after that preparation step can the product move onto the eight-station turntable for sleeve insertion and heat shrinking.

Heat-shrink control with downstream cooling

The sleeve process is not finished at insertion. The line has to shrink the sleeve with hot air, cool the part and unload it without mixing finished product with lead-cutting waste. The equipment therefore includes hot-air heat-shrink components, air cooling, unloading and a waste-bin section.

Process sequence

The operating route is:

1. Feed bulk varistors through the vibratory bowl.
2. Load the sleeve roll onto the support position.
3. Use the manipulator to clamp, correct and cut leads.
4. Transfer the prepared product to the rotary clamping position.
5. Move the product onto the eight-station turntable.
6. Detect product presence with a fiber sensor.
7. Insert the sleeve.
8. Heat-shrink the sleeve at the fourth and fifth stations with hot air.
9. Cool the product at the sixth station.
10. Unload finished product at the seventh station.
11. Collect cutting waste in the waste-bin section.

Functional modules

The machine consists of a vibratory bowl feeding module, a four-station manipulator loading module, rotary clamping, an eight-station turntable, detection module, sleeve hot-air heat-shrink module, unloading module and waste-bin module.

Module	Confirmed role
Vibratory bowl feeding	Feeds bulk varistors into the station
Four-station manipulator	Clamps, corrects, cuts leads and transfers product to the clamping position
Rotary clamping	Moves prepared parts onto the eight-station turntable
Detection station	Uses fiber sensing to confirm product presence
Sleeve station	Applies sleeve material before heat shrinking
Hot-air stations	Fourth and fifth stations perform hot-air heat shrinking
Cooling station	Sixth station performs air cooling
Unloading and waste sections	Separate finished product unloading from lead-cutting waste collection

Reference specifications

The reference machine size is 1,250 x 770 x 1,950 mm, L x W x H. The required air supply is 0.5 to 0.6 MPa, the power supply is AC220V, and the control package uses PLC plus an industrial computer. The listed capacity is 800 to 1,200 pieces per hour for one machine, with one operator required.

Item	Confirmed specification
Reference size	1,250 x 770 x 1,950 mm, L x W x H
Air supply	0.5 to 0.6 MPa
Power supply	AC220V
Capacity	800 to 1,200 pieces per hour
Control	PLC plus industrial computer
Operator count	1 operator

Proposed operating result

The resulting station turns sleeve forming into a defined automatic route: bulk feeding, lead preparation, rotary transfer, sleeve application, two hot-air shrinking stations, cooling, unloading and waste separation.

Process value

The practical value is compact integration. A single operator can support bulk feeding and sleeve-roll loading while the machine handles correction, cutting, sleeve forming and unloading. The available project data does not include equipment price, labor saving or payback period, so we do not assign an ROI figure.