In engine-assembly lines, large housing-type components—such as timing-chain covers, cylinder-head covers, and oil pans—are typically secured by several bolts arranged on the same plane. The bolts are of the same specification but large in quantity. The prevailing automated solution is a multi-spindle bolt-tightening machine whose torque can be adjusted and controlled; all bolts are tightened simultaneously.
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Yet automatic multi-spindle tightening faces two main difficulties:
Size and weight
An engine cylinder-head, for example, may have 18 bolts. When each spindle is paired with a conventional tightening module, the entire machine becomes bulky and heavy, which is unacceptable on space-restricted assembly lines. Very few suppliers in the industry can deliver machines with more than ten spindles.
High failure rate and poor maintainability
Many spindles require many traditional modules. Their high travel speed can impact the spindles, damaging sensors and raising failure rates. The spindles are packed tightly together, leaving little room for maintenance.
Without a tightening-module concept that moves in perfect synchrony with the continuous conveyor, it is hard to engage all these bolts in one pass, jeopardizing both quality and economics. To solve these problems, Danikor offers an ultra-compact, integrated tightening module that forms a 12-spindle multi-bolt tightening system for automatic engine-assembly lines.
The advantages of this integrated tightening module are four-fold:
Monolithic structure
Compact, with no external moving parts → saves floor space.
Narrower and smaller → fits tighter bolt patterns and complex work envelopes.
Lighter (20–30 % weight reduction) → allows use with 5 kg-class robots or 3-axis gantries.
Simple pneumatic/electric routing; cables are fixed—no drag chains.
Collaborative high quality
Patented design: the suction tube stops at the pick-up position for reliable screw capture, ensuring perpendicularity and stability.
Active-opening jaws eliminate impact wear on the suction tube, extending its life.
Fixed mounting reduces shocks on the tightening tool, safeguarding sensors and prolonging tool life.
Greater convenience
Bit change: Instead of removing the entire tool, only the nose of the integrated module needs to be detached; the cylinder extends and the bit is swapped in seconds.
Down-force adjustment: A simple regulator in the pneumatic line changes tightening down-force—no need to swap springs.
Safer operation
No external Z-axis mechanism improves safety, making the system ideal for human-robot collaboration.
By ensuring the reliability of automatic multi-spindle bolt-tightening machines, this integrated module significantly boosts engine-assembly throughput while maximizing assembly quality.