QJR3-400S Six-axis robotic arm (manipulator)
3kg / 400mm
QJR3-400S specifications
QJR3-400S industrial robot, with a load of 3kg and an armspan of 400mm.
QJR-S Series Small High-Speed Robots · Series technical features
3-20kg · Short reach, fast beat
400-1000mm short arm span, maximum repeat positioning accuracy of ±0.01mm (QJR3-400S).
The official website categorizes applications into loading/unloading, assembly, and sorting categories.
The compact machine body is suitable for machine tools and narrow workstations.
QJR-S Series Small High-Speed Robots · Other models in the same series
Compare load and reach to choose the model that best suits your process.
QJR3-400S model positioning and working condition adaptation
QJR3-400S It belongs to the QJAR Robotics QJR-S series of small high-speed robots, featuring a rated load of 3kg, a motion radius of 400mm, and a repeat positioning accuracy of ±0.01mm. QJAR Robotics' technical foundation is based on the background of QJAR motorcycle equipment manufacturing, with the QJR series focusing on welding and general handling both for its cost-effectiveness. The control platform is the QJAR Controller (QJR platform), and the program ecosystem consists of graphical programming + welding process packages.
From the perspective of working condition adaptation, typical applications for small load (3kg) positioning are:High-speed sorting, precision assembly, dispensing coating, and inspection/pick-and-place processingThe short reach (400mm) keeps the machine compact, suiting dense workstations and close-range pick-and-place with a small workcell footprint. Repeatability of ±0.01mm is precision-class, meeting path requirements for precision assembly, dispensing and vision-guided inspection. Even with a light payload, keep the total end-effector and workpiece weight within 70% of the rated value, and leave enough acceleration margin for high-speed cycles.
| Parameters | Engineering interpretation and usage recommendations |
|---|---|
| Rated load 3kg | It is recommended to reserve a load margin of 20%–30%; Verification is made by combining end self-weight + workpiece + imbalanced load inertia, especially sensitive to high-speed conditions |
| Movement radius: 400mm | Determine the radius of the work unit layout: bins, tooling, and fences are bounded by maximum arm span + safety distance; Verify the accessibility of each pick-and-place point during cross-station service |
| Repeat positioning accuracy: ±0.01mm | Repeatability ≠ absolute accuracy: Precision assembly requires external measurement closed-loop or visual guidance; Long-term accuracy trends rely on annual retest management |
| Controller: QJAR Controller (QJR platform) | Decide on the process ecosystem, spare parts channels, and second-hand residual value; Currently, spare parts channels are smooth, and repair and upgrade paths are mature |
Control systems and common failure modes
The QJAR controller (QJR platform) compatible with the QJR3-400S features a programming language and development environment of graphical programming + welding process packages. Maintenance of this generation of control platforms focuses on three basic components: power, storage, and cooling—most "sudden downtime" can be detected in advance when preventive maintenance is in place.
| Failure mode | Typical performance | Disposal recommendations |
|---|---|---|
| Driver overcurrent alarm | Driver overcurrent alarm | Included as a mandatory inspection item for annual maintenance, with spare parts stocked in advance |
| Encoder cable interference | Encoder cable interference | Initial interpretation of alarm codes by reference with manuals, remote diagnosis allows for early positioning |
| Welding process parameter drift | Drift of welding process parameters (welding machine linkage) | Daily inspection coverage, with abnormal trends (abnormal noises/temperature rise/errors) recorded |
| Showing the wear and tear of the teaching device | Showing the wear and tear of the teaching device | Quarterly dust removal maintenance and cabinet temperature monitoring |
| Maintenance projects | Cycle recommendations | Key points |
|---|---|---|
| Batteries should be replaced periodically | By cycle | Batteries should be replaced periodically |
| Welding linkage parameters should be regularly calibrated | Periodically | Welding linkage parameters should be regularly calibrated |
| Reducer lubrication management | According to the manufacturer's manual cycle | Reducer lubrication management |
| Cable and drag chain inspection | every six months | Insulation, shielding, and bending radius inspection of power and encoder lines, as well as wear of cables inside the drag chain, are the main causes of intermittent faults |
| Zero point and accuracy retest | Every year | Repeatability measured by dial gauges or laser trackers, drift trend digitization—accuracy degradation can be seen six months in advance |
| Control cabinet dust removal and fans | Every quarter | Filter cleaning, fan speed and noise checks, cabinet temperature recording; Dust environments shorten the cycle |
Henghuan's service capabilities for the QJR3-400S
We are a third-party robot technical service provider. For the QJR3-400S we offer the following eight services, ordered by how often they are actually needed for this model:
- Maintenance and repair: on-site diagnosis, board-level repair and annual maintenance contracts for the QJR3-400S — brand-specific items such as periodic battery replacement are performed per our SOPs; same-day response within Sichuan and Chongqing.
- Second-hand and inventory robot sales: used prices are affordable, making this a budget-friendly choice for welding and handling duty; always run an all-axis accuracy test before buying; in-stock QJR3-400S or equivalent models come with a full-function inspection report and a 12-month warranty.
- Sales of new industrial robots: When adding new production lines or replacing entire batches, we conduct cross-brand selection comparisons based on process requirements (including models of the same class as QJAR Robotics), and provide configuration and pricing plans.
- Applied technology services: process programming, path optimization, cycle-time tuning and changeover recipe management for the QJR3-400S, commissioned specifically for high-speed sorting, precision assembly, dispensing/coating and inspection pick-and-place.
- Research and development of automation equipment: Custom fixture ends, peripheral tooling, and safety fences for QJR3-400S, with interfaces designed according to QJAR Robotics flange and IO standards.
- Robot rental: for short-term capacity needs or process validation, you can rent an in-stock QJR3-400S-class model, with transport, installation and commissioning included; rental terms are flexible and the unit can be purchased at the end of the lease.
Common issues with this device
Is it easy to find spare parts for the QJR3-400S?
QJAR Robotics: Spare parts channels for this generation are smooth; we have in-stock or short-cycle channels for standard parts such as drivers, power modules, batteries, and teach pendant components; It is recommended to configure consumables for battery replacement periodically according to the annual maintenance contract.
With a rated load of 3kg, how much weight can it actually handle?
The rated load is the static load limit of the flange surface. In actual selection, three factors must be considered: the self-weight of the end fixture (vacuum suction cup groups or grippers often account for 2–5kg), the inertia generated by the workpiece offload (checked according to the inertia ratio when the center of gravity deviates from the flange center), and the dynamic load during high-speed movement. The conventional engineering practice is to keep the "end + workpiece" within 70%–80% of the rated value to ensure cycle time and service life.
If the equipment's accuracy deteriorates after several years of use, how can it be restored?
According to the inspection order: first check whether the zero point is drifting (common after collision or battery depletion), then perform zero calibration; Check the reducer's return error (actual measurement of forward and reverse positioning deviation; if exceeded, disassemble or replace); Then check the installation base fastening and foundation settlement; Finally, trajectory compensation parameter restructuring. Most accuracy issues can be mostly restored after calibration and maintenance, so there is no need to rush into major repairs—we first release the inspection data before deciding on the plan.
Is the used QJR3-400S worth buying?
Affordable second-hand prices, budget-friendly options for welding and handling conditions; Perform full-axis precision inspection before purchasing. Three essential items for second-hand procurement: comprehensive inspection reports (axial accuracy, driver status, insulation and battery), maintenance history and operating hours, controller generation, and software license integrity. Every used machine we sell comes with inspection records and a 12-month warranty, and we can also accept third-party inspections designated by customers.
Need technical support or procurement for this model?
Whether it's model selection comparison, installation and commissioning, or maintenance of in-use equipment, you can contact Henghuan. Tell us about your processes, loads, and equipment status, and we will provide third-party technical support and solution recommendations.
Contact HenghuanBack to the full series