18 Colors Dispensing Machine: Working Principle

An 18 colors dispensing machine is automated equipment capable of dispensing multiple colors of liquid materials-typically PVC, silicone, or similar polymers-into molds or onto substrates in a single production cycle. As the name suggests, it is configured with eighteen separate material channels, enabling the simultaneous or sequential deposition of eighteen distinct colors.

This article explains what the machine is, how it works, and the core principles that govern its operation.

What Is an 18 Colors Dispensing Machine?

A dispensing machine, also known as a dripping machine, is specialized equipment that controls fluid and automatically injects flowing liquids into molds. When configured with eighteen color channels, the machine can produce multi-colored products with complex patterns and layered color schemes that would be impractical to achieve through manual methods.

These machines are widely used in the production of soft PVC and silicone products, including keychains, badges, labels, phone cases, luggage tags, promotional gifts, and molded toys. An 18-color configuration sits at the higher end of standard offerings, which typically range from 8 to 24 colors depending on production requirements.

The core value of an 18-color machine lies in its ability to handle complex, multi-color designs automatically. A single operator can manage two to three machines simultaneously, significantly reducing labor costs compared to manual dispensing.

Core Working Principle

The working principle of an 18 colors dispensing machine can be understood through five key stages: production file creation, material preparation, coordinate positioning, controlled dispensing, and layer formation.

Stage 1: Production File Creation

The product design is first converted into a machine-readable program. This program defines the dispensing paths, coordinates, colors, and sequence required for the product. Modern machines use computerized controls or teach pendants to program these parameters, allowing the same design to be reproduced repeatedly without manual marking.

Stage 2: Material Preparation and Supply

Each of the eighteen color channels is loaded with a different liquid material, typically PVC plastisol or silicone. These materials are stored in separate barrels or containers and fed through individual delivery systems.

Maintaining stable material flow is critical. Variations in viscosity, temperature, or pressure can affect the amount of material dispensed and lead to inconsistency. Some dispensing systems incorporate automated stirring mechanisms to keep colorants or materials uniformly mixed and prevent sedimentation.

Stage 3: Coordinate Positioning and Motion Control

The dispensing head moves along programmed X, Y, and Z coordinates. The X and Y axes control the horizontal dispensing path across the mold, while the Z axis controls the dispensing height.

This motion is typically driven by servo motors or stepper motors, which provide the precision needed for multi-color work. Repeat positioning accuracy of ±0.01 mm is common in high-quality machines, ensuring that each color is deposited in precisely the correct location across production cycles.

The machine follows the programmed path for each color, dispensing material only where that specific color is required. This allows the machine to build up complex multi-color patterns sequentially.

Stage 4: Controlled Dispensing

When the dispensing head reaches the programmed position, the machine releases a controlled amount of material. The dispensing action is typically driven by compressed air or motorized pumps.

In a typical dispensing system, a piston or valve mechanism controls the release of material from the corresponding channel. When the valve opens, the material flows from the supply container through the feed pipe to the dispensing needle. The amount dispensed is controlled by factors such as valve open time, pressure, and nozzle diameter.

Modern machines achieve dispensing material error of ≤±1%, which helps control material consumption and reduce waste. Some high-precision systems use piston/cylinder pump arrangements where the piston stroke directly determines the volume dispensed, providing highly repeatable results.

Stage 5: Layer Formation and Curing

After one layer or color is dispensed, the material is typically heated and stabilized before additional colors or layers are applied. This process may be repeated several times until the complete multi-layer, multi-color structure is formed.

This layer-by-layer approach enables manufacturers to create raised edges, three-dimensional logos, and detailed patterns that would be difficult or impossible to achieve through flat printing methods. The heating and curing steps ensure that each layer solidifies properly before the next is applied, maintaining the integrity of the final product.

Key Components of an 18 Colors Dispensing Machine

The machine consists of several integrated systems working together:

Material Supply System: Eighteen separate containers or barrels, each holding a different color material. Each container connects to its own feed line.

Dispensing Head Assembly: Contains the dispensing valves, needles, and mixing mechanisms. In multi-color machines, each color typically has its own dedicated dispensing channel, preventing cross-contamination between colors.

Motion System: The X, Y, and Z axes with servo or stepper motors, guide rails, and transmission components that position the dispensing head precisely.

Control System: The computerized brain of the machine, which stores production programs, coordinates the motion system, and controls the opening and closing of dispensing valves according to the programmed sequence.

Frame and Work Table: Provides structural support and holds the mold or substrate in position during dispensing. Some machines include adjustable platforms to accommodate different product sizes.

Why Accuracy Matters in Multi-Color Dispensing

In multi-color production, each color must be placed in its correct area of the mold. If the dispensing position shifts between production cycles or between colors, several problems can occur:

Color misalignment between layers

Uneven borders or edges

Inconsistent product details

Material overflow into adjacent color zones

Increased rework and material waste

This is why repeat positioning accuracy of ±0.01 mm is an important specification for multi-color dispensing machines. This level of precision ensures that the machine returns to the same programmed position consistently, maintaining color registration across thousands of cycles.

Summary

The 18 colors dispensing machine represents a significant step up from manual multi-color production. By combining precise motion control, independent color channels, and programmable operation, it enables manufacturers to produce complex multi-color products consistently and at scale.