Time：2026-11-06
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As the new energy vehicle (NEV) industry grows rapidly, e-drive systems are becoming highly integrated, lightweight, and structurally complex. The transmission—a key part of the e-drive—demands many bolted connections across different directions and positions during case closing and internal assembly. This raises the bar for automated tightening equipment in spatial adaptability, synchronized operation, and assembly precision. Danikor answers with a combined automatic screw feeding and smart tightening solution built on multi-axis variable-pitch synchronous tightening, blow-suction combined feeding, and sleeve floating compensation.
E-drive systems are trending toward high integration, light weight, and structural complexity. The NEV transmission involves numerous bolted joints on different planes and positions during housing case closing, transmission-mechanism, and internal-structure assembly—imposing stricter requirements on the spatial adaptability, synchronized operation capability, and assembly accuracy of automated tightening equipment.
Especially at the case-closing station, the complex housing and irregular bolt distribution mean some bolts are obstructed by surrounding structures, reinforcing ribs, and other components. Traditional single-axis, one-by-one tightening is easily constrained by cycle time and spatial layout. How to achieve automatic feeding, flexible clearance, and synchronous tightening of multiple bolts within limited equipment space—while guaranteeing joint quality—has become a critical problem for NEV transmission automation.
The transmission housing is complex, with case-closing bolts distributed across different planes and directions. Some sit in deep holes, on side faces, or in narrow spaces, forcing the tightening tool to adjust its posture to each hole. A fixed-structure multi-axis device is easily obstructed by the housing and struggles to cover every bolt position.
Bosses, reinforcing ribs, and other structural parts surround the housing, so each bolt position needs a different clearance height. Traditional fixed-stroke or spring-downward methods cannot flexibly adapt to these height differences and may cause tool-to-workpiece collisions, hurting equipment stability.
Case closing typically involves many bolts. A single-axis, one-by-one feed-and-tighten approach repeats pick-up, positioning, and tightening for every bolt. As bolt count grows, per-bolt time directly drags down the station cycle time, wasting the efficiency advantage of automation.
Influenced by housing machining accuracy, fixture positioning, and accumulated assembly errors, the actual bolt-hole position may deviate from the equipment's theoretical coordinates. If the tightening sleeve cannot align with the bolt axis, the bit or sleeve may fail to fit smoothly and the bolt may be mispositioned—in severe cases causing thread damage or fastening failure.
Therefore, automatic case-closing tightening must solve not only multi-axis synchronization, but also spatial clearance, hole-deviation compensation, and stable feeding.
Targeting these pain points, Danikor adopts a system combining multi-axis variable-pitch synchronous tightening with automatic screw feeding, custom-configured to the housing structure, bolt distribution, and equipment space—delivering flexible feeding, synchronous tightening, and process control for many bolts at once.
For housings with many irregularly distributed bolts, a multi-axis variable-pitch synchronous tightening mechanism adjusts the spacing between spindles to match the bolt-hole layout, so multiple spindles adapt to different bolt positions. Within process limits, the multi-axis unit fastens several bolts simultaneously, reducing the repeat actions of one-by-one tightening.
Multi-axis coordination cuts the time spent fastening bolts individually.
Variable-pitch design improves adaptability to different hole layouts.
Spindle spacing and mechanism layout are customized to the housing.
Optimized motion paths raise the overall station cycle time.
During synchronous multi-axis tightening, ensuring each spindle reliably receives a screw is key to continuous operation. Danikor configures a blow-suction combined feeding module based on screw spec, feed distance, and station layout.
Blow feeding transports screws by airflow to a target position where conditions allow.
Suction feeding (vacuum pickup) retrieves and positions screws via vacuum, configured to the actual station structure.
This combination supplies the multi-axis unit flexibly and reduces manual pick-up and repeated loading.
Automatic screw supply reduces manual intervention.
Feed method is configured per axis position and station space.
Supports flexible multi-axis layout.
Coordinated feed-and-tighten motion under automation control.
For height differences, bosses, and structural interference around the housing, Danikor applies a servo module with clearance height control, setting differentiated travel for each tightening position. Via servo control, the suction tube or actuator stops at designated positions, flexibly controlling the clearance stroke. Compared with fixed-stroke or pure spring-compression methods, servo control adapts more flexibly to different products and heights, reducing the need for extra Z-axis mechanisms.
Set clearance height per bolt position.
Adapt to complex housing structures and varying height differences.
Reduce mechanism-interference risk.
Optimize equipment space layout and improve system flexibility.
For insufficient hole-position consistency and workpiece positioning deviation, Danikor uses sleeve floating compensation. When a bolt hole deviates from the spindle's theoretical center, the floating mechanism provides mechanical compensation so the sleeve can re-center within an allowed range, improving sleeve-to-bolt alignment.
Compensate hole-position and positioning deviations within tolerance.
Improve sleeve-to-bolt centering adaptability.
Lower fastening-failure risk from position deviation.
Reduce over-reliance on fixture and equipment positioning accuracy, helping control retrofit cost.
Note: floating compensation is not unlimited position correction—the compensation range must be designed around the bolt spec, hole deviation, and floating mechanism structure.
For the case-closing station, automation must coordinate feeding, positioning, fastening, and quality judgment—not just whether a bolt is tightened. Danikor's integrated system performs this workflow:
Automatic feeding: the screw-feeding mechanism arranges, separates, and conveys screws.
Screw-in-position confirmation: detection confirms the screw reached its position before fastening.
Multi-axis positioning & clearance: adjust spindle spacing and per-position clearance height to the housing.
Sleeve floating compensation: mechanically compensate in-range hole deviations to improve alignment.
Synchronous tightening: multi-axis units fasten multiple bolts per the preset process.
Quality judgment & data management: smart tightening tools monitor torque, angle, and results, performing OK/NG judgment for data traceability.
Coordinated control reduces manual intervention, improves assembly stability, and provides data for downstream quality analysis and process optimization.
Improved cycle time: multi-axis variable-pitch synchronous tightening cuts repeat one-by-one actions, shortening case-closing station time.
Higher equipment flexibility: variable-pitch structure and differentiated clearance height adapt to varied bolt distributions and complex housings.
Higher fastening success: blow-suction combined feeding plus sleeve floating improve common feeding and alignment problems.
Lower automation retrofit cost: sensible mechanism design and floating compensation reduce dependence on ultra-high-precision positioning and extra motion mechanisms (actual savings assessed per project).
Stronger quality management: smart tightening tools monitor torque, angle, and results, giving data backing to critical joint processes.
As e-drive integration deepens, the transmission case-closing station faces many bolts, complex spatial interference, hole deviations, and tight cycle-time demands. Through multi-axis variable-pitch synchronous tightening, blow-suction combined feeding, servo clearance-height control, and sleeve floating compensation, Danikor delivers a more flexible feeding-and-tightening solution for NEV transmission automation—folding feeding, execution, and quality control into one automated flow to help automakers raise both assembly efficiency and joint quality.
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