A new solution for assembly, in electrical- electronics industry, screws with 0.8 ratio

Semi-automatic assembly of condenser batteries for power factor-correction systems with M6x8 screws at about 7 Nm torque. The screws, extremely specific due the 0.8 ratio between total length and head diameter, cannot be processed with the standard screw feeding systems

The solution

Fiam designed and manufactured an autofeed screwdriver with transducerized brushless DC electric motor, torque and angle control, to be used by the operator on the work bench

The most interesting innovations introduced in order to handle such particular screws are: "T" shaped blowing hose mirroring screw design.Tightening head receiving the screw from the side rather than axially as normally happens. What above described allows feeding screws without jamming

The tightening module is composed of a screwdriver equipped with:

- Straight grip with lever start to ease start by the operator

- Brushless DC electric motor MCB line with torque and angle control

- Forward bit stroke device with positive screw engagement to keep screw always visible to the operator, thus facilitating centering while preventing screw retraction into the jaw set

- Jaw set with a special screw retaining solution which holds the screw from the head rather than the shank, to ease access to the tightening point

BC CARTESIAN ARM: installed on the work bench, in addition to relieving screwdriver weight, allows keeping the tool upright, ensures maximum ergonomics of the work place and prevents any reaction on the operator''s wrist

MULTIFUNCTION PANEL: useful for selecting one among the different tightening programs set in the feed and control unit TCS -B

FEED AND CONTROL UNIT TCS-B: provides programming and control functions of the tightening cycle plus control of electric power supply

SCREW FEEDING SYSTEMS: the vibrating bowl of the screw feeding unit prevents any jamming and ensures production continuity. The extendable device cover, in addition to soundproofing, allows rapid screws supply into the bowl

Solution benefits:

Waste reduction: thanks to programmability, management of the tightening cycle, traceability of the process and elimination of the post-process controls, assembly operations become precise, reducing the amount of waste: a crucial advantage to the benefit of products quality

Maximum ergonomics and productivity: assembly operations become faster, more reliable (without jamming) and also safer for the operator: the solution avoids any effort and facilitates the job