Insert machine for weaving reed holders: easier to operate, increased output and quality

Challenge

Picanol, a global manufacturer of weaving machines, wanted to automate the process of inserting and fastening inserts into reed holders.

The goals of automating this step:

enable a single operator to run this insert machine and the milling machine simultaneously;
reduce cycle times;
increase total output;
and standardize product quality.

We faced several challenges when engineering this insertion machine.

Variability

There is a variable number of inserts per reed holder, ranging from 16 to 61.

The insert machine must be able to handle three different types of reed holders, with lengths varying between 1900 and 5400 mm. The clamping unit, for instance, had to be engineered to accommodate these different mechanical designs.

Operator specifics

The operator must be able to load two reed holders simultaneously. If the lengths are below 2,5 m, the capacity increases to four holders.

Accuracy and speed

Positioning accuracy is approximately 0.1 mm. Inserts need to be screwed in at a precise torque of 25 Nm. An expected cycle time of 20 seconds per insert was put forward.

Footprint of the insert machine

Although the final products can reach lengths of up to 5.4 meters, we had to keep the insertion machine’s footprint as compact as possible.

Quality control

Integrated automatic quality control was essential to guarantee the accuracy of both position and torque.

Solution

Let’s zoom in on the three most important parts of this insertion machine

The machine frame
The screwing unit
And the integrated vision

1. Machine frame

We designed and manufactured a perfectly milled, solid 6,6 m frame, featuring perfectly aligned linear guides for the screwdriving unit carriage.

Regardless of the reed holder type, the loading procedure always remains the same. The operator manually positions the holders against the mechanical stops of the insert machine, after which they are pneumatically clamped at the start of the cycle.

2. Screwdriving unit carriage

For the automatic screwing unit, we developed a solution in collaboration with the Weber Group, a specialist in tools and automation solutions for the metal industry.

The solution consists of an automatic screwing head with

integrated depth measurement
torque control
recipe management
and a step feeder

Since inserts must be installed across the entire length of the reed holder, we mounted the screwing unit and feeder on a rack-and-pinion controlled carriage. This assembly moves along the full length of the reed holders.

To reach both rows, we integrated a servo spindle for horizontal movement. Additionally, as different reed holder variants require different approach angles, we included a servo-controlled tilt movement.

3. Integrated vision

We integrated a Keyence smart camera system onto the moving carriage. This vision system serves two major purposes:

1. Guaranteeing position accuracy before screwing

Since the reed holders are manually loaded, the camera verifies whether the 0.1 mm positioning accuracy is met. It adjusts the absolute screwing coordinates accordingly.