What are the differences between three-axis and five-axis injection molding manipulators? What are the differences in installation?

The core differences between three-axis and five-axis injection molding manipulators are the number of axes (freedom of movement), functional complexity and applicable scenarios. The installation differences focus on positioning accuracy requirements, linkage logic and spatial adaptation. The specific comparison is as follows:

First, the core difference: the number of axes and functional positioning

Comparative dimension three-axis injection manipulator five-axis injection manipulator

Axis number and motion x (traverse), y (front and back) and z (elevation) are three linear axes, and only three axes (x/y/z) plus two rotating axes (axis A: rotation around the z axis, axis B: rotation around the x axis) based on three-dimensional linear motion can be realized, which can realize linear+rotation compound motion.

The core functions are simple picking and blanking, which can only move along a fixed path, but cannot adjust the posture of plastic parts, such as complicated picking, posture adjustment, insert implantation and multi-station transfer. The angle of plastic parts can be flexibly adjusted to adapt to complex molds and processes.

Applicable scenes: common horizontal/vertical injection molding machine, simple plastic parts (such as shells and plates), single-process production of two-color/multi-color injection molding machines, high-speed machines, complex plastic parts (with inserts and special-shaped parts), and multi-process cooperation (taking parts+inserts+testing).

The repeated positioning accuracy is medium (0.1 ~ 0.2 mm) and higher (±0.05~±0.1mm), and the rotating shaft is positioned accurately.

The operation complexity is simple, the parameter setting is few and complicated (only the linear path needs to be set), so it is more difficult to debug.

Second, the key differences in installation

1. Installation orientation and space requirements

Three-axis manipulator:

The installation is simple, and it only needs to be fixed on the side, top or workbench of the fixed template of the injection molding machine, and the levelness error is less than or equal to ≤0.5mm/m/m, which requires low flatness of the installation surface.

Small space requirement, only need to reserve a linear motion path (no rotation interference), suitable for small and medium-sized injection molding machines, no need to expand the installation space.

Five-axis manipulator:

The positioning accuracy is required to be higher, the levelness error of the fuselage is less than or equal to ≤0.3mm/m/m, and the verticality (error is less than or equal to ≤0.1mm/m/m) should be calibrated when installing the rotating shaft to avoid posture deviation during rotation.

Space for rotating motion should be reserved, and the installation position should avoid molds, pull rods and safety doors to ensure that there is no interference when the A/B axis rotates (there is no obstacle within the rotating radius), and usually more installation space is needed.

2. Fixation and connection methods

Three-axis manipulator:

It is fixed by simple bolts, and the connection between the machine body and the injection molding machine does not need special shock absorption measures (only heavy-duty models need to be equipped with gaskets), and the stability can be met if the number of fixing points is ≤4.

There are few pneumatic/electrical interfaces, only the X/Y/Z axis drive and fixture air source need to be connected, and the wiring is simple.

Five-axis manipulator:

It is necessary to strengthen the fixation. The connection between the machine body and the injection molding machine needs to be equipped with shockproof pads (the rotation movement is easy to produce vibration), and the number of fixing points is ≥6, and it needs to be fixed on the load-bearing structure (to avoid shaking when rotating).

There are two more rotary shaft drive interfaces, which need to be connected with the rotary shaft motor control line and encoder signal line, and the wiring needs to distinguish between the straight shaft and the rotary shaft line to avoid interference.

3. Linkage debugging differences

Three-axis manipulator:

The signal docking is simple, and only the basic signal of "mold opening is completed → parts taking → blanking → mold closing" needs to be associated, without complicated time sequence matching.

Path debugging: manually calibrate the pick-up point and blanking point of X/Y/Z axis, and set the linear motion speed, and it will be stable after 3~5 trial runs.

Five-axis manipulator:

The signal linkage is complex, so it is necessary to correlate the cooperative signals between the rotating shaft and the foundation shaft (such as "After taking the parts, the A-axis rotates 90°→B the B-axis tilts 30 → the insert is implanted"), and it is necessary to match the mold action of the injection molding machine (such as the rotation signal of the two-color machine).

Path debugging: it is necessary to calibrate the coordinates of the linear axis and the angle of the rotating shaft respectively, simulate the compound motion path, and repeatedly test the attitude accuracy during rotation. The number of mold trials is more (10~20 times), and the rotating shaft needs to be calibrated with a laser locator.

4. Fixture and accessories installation

Three-axis manipulator:

Only simple fixtures (suction cup, fixed jaw) are suitable, and the fixture is directly installed at the end of Z axis, without additional switching structure.

Five-axis manipulator:

It is necessary to install a rotating fixture or an adapter flange (connecting the Z axis and the rotating shaft), and the fixture should adapt to the rotating motion (light weight, stable center of gravity, and avoid imbalance during rotation).

If insert implantation is involved, additional positioning fixture (linked with rotating shaft) shall be installed to ensure accurate insert implantation angle.

5. Safety protection settings

Three-axis manipulator:

The safety protection is simple, just set the limit of linear motion stroke, and the safety light curtain covers the linear path.

Five-axis manipulator:

Both linear travel limit and rotation angle limit (the rotation range of axis A is usually 180 and axis B is 90) should be set at the same time, and the safety light curtain should cover the rotating movement area to avoid colliding with people or equipment during rotation.

It is necessary to additionally set up the emergency stop linkage of the rotating shaft to ensure that the rotating shaft is locked immediately and there is no inertia rotation during emergency stop.

Third, summary

Three-axis manipulator: "simple and practical", with fast installation and easy debugging, suitable for basic picking of conventional plastic parts, low cost and convenient maintenance.

Five-axis manipulator: "flexible and accurate", with high installation requirements and complex debugging, but it can adapt to complex processes, improve production efficiency and product quality, and is suitable for middle and high-end injection molding production.