Korea Ever-Power · NMRV Series · Packaging Machine Drive Guide

NMRV worm gearmotors at ratios of 40:1 and above are reliably self-locking — the output shaft cannot be back-driven by load forces when the motor is stopped. For packaging applications where the driven mechanism is essentially frictionless during the dwell phase (label applicator drum at rest, auger filler screw at rest between fills) and where stopping at the exact position of a mechanical cam stop is acceptable, the worm gear self-locking at 40:1 or above eliminates the need for a separate brake motor. The motor simply stops and the self-locking worm holds the position passively without any additional holding torque.

A Y2EJ brake motor is required in place of a standard Y2 when: the machine operates at a gear ratio below 30:1 where self-locking is not reliable; when high-frequency stop-start cycling requires a defined and repeatable stop time for tooling registration accuracy; when the packaging machine has a safety guard interlock that requires motor stop confirmation before the guard can be opened; or when the film or product must stop within a defined distance to prevent overshoot that would misregister the seal position. At gear ratios between 20:1 and 35:1, always specify the Y2EJ brake motor to avoid relying on the uncertain self-locking behaviour in this transition zone.

The output shaft stop position repeatability of an NMRV gearmotor with Y2EJ brake depends on the stop time consistency and the load inertia. At a consistent stop time of 0.2 s from an output shaft speed of 60 rpm, the output shaft rotates (60 rpm ÷ 60 s) × 0.2 s = 0.2 revolutions during braking. For a film feed roller with 150 mm circumference, this corresponds to 30 mm of film overshoot — which must be accounted for in the mechanical cam stop or electronic cycle length setting. The stop position is highly repeatable cycle-to-cycle because the brake torque and load inertia are constant, making the NMRV + Y2EJ combination suitable for registration-dependent packaging functions.

The motor brake stops the motor shaft in 0.1 to 0.4 seconds depending on motor size and brake torque. The output shaft stop time is the same as the motor shaft stop time because the worm gear does not introduce significant additional inertia at the output speed (the motor inertia dominates total system inertia reflected to the motor shaft). Output shaft overshoot after the brake engages = (output rpm ÷ 60) × t-stop × 360° — this overshoot angle must be within the registration tolerance of the machine application.

The Y2EJ brake motor includes a manual release lever that allows the maintenance technician to release the brake and rotate the output shaft by hand when the machine is jammed or when setting the tooling position before a production run. The manual release must be disengaged and confirmed returned to the automatic position before the machine is returned to production. Korea Ever-Power Y2EJ motors include a visual indicator on the manual release mechanism to confirm the brake is in automatic mode.

Standard NMRV thermal ratings assume continuous S1 duty at rated input power. For packaging machine intermittent duty with a 40 to 60% on-time CDF, the gearbox can accept an input power 15 to 25% above the S1 thermal limit. However, at high cycle rates (above 120 cycles/min) the gearbox heat generation from repeated meshing impacts may approach the S1 continuous thermal limit even at partial load. Verify the gearbox housing temperature during initial machine trials at maximum production rate and confirm it stays below 80°C after 2 hours at peak rate.

The Korea Ever-Power Y2EJ brake motor is rated for a maximum of 240 braking operations per hour (operating class AC3 per IEC 60947). At 60 packs/min this equates to 3,600 braking operations per hour — 15 times the rated limit. For packaging machines above 30 cycles/minute with a Y2EJ brake motor, the drive architecture must use a servo motor, a stepper motor with gearbox, or a mechanically indexed cam-driven arrangement rather than the start-stop motor approach. The Y2EJ is suitable for packaging machines up to 30 cycles/minute (1,800 cycles/hour) if a 2.0 safety factor on the brake rating is applied, reducing the effective limit to 120 cycles/hour = 2 cycles/minute — appropriate for slow carton erectors, case sealers, and pallet wrappers rather than high-speed film packaging.

Korea Ever-Power supplies NMRV worm gearmotors as matched and assembled combinations of Y2 (standard) or Y2EJ (brake) motors with NMRV 025 through 090 worm gear reducers. The motor connects directly to the NMRV IEC B5 input flange — no coupling, no adapter, and no alignment procedure — and the complete unit is delivered ready to bolt down to the machine frame. The full gearmotor range with all standard ratio and size combinations is available in the gearmotor combination product section. For packaging machine OEM customers requiring custom output shaft configurations (hollow shaft, dual shaft, or extended shaft), please contact the technical team.

Label peel and feed roller on self-adhesive labelling machines. NMRV 040–050 with Y2 at 18:1 to 50:1 for label drum at 20 to 80 rpm. Self-locking at 40:1 or above provides position hold between label cycles without brake motor.

Infeed and discharge conveyor drives on shrink-wrap tunnels run continuously at fixed speed — NMRV 050 with standard Y2 (no brake) at 10:1 to 20:1 for 60 to 150 rpm output. No start-stop cycling; continuous S1 duty thermal rating applies.

Case sealer infeed and outfeed conveyors use NMRV 063 with Y2EJ at 20:1 to 40:1 for accurate case positioning at the sealing heads. Low cycle rate (below 20 cases/min) keeps starts below the Y2EJ 240 braking operations/hour thermal limit.

Turntable drive on rotary arm pallet stretch wrappers uses NMRV 075–090 at 40:1 to 60:1 for slow turntable rotation at 5 to 15 rpm. Self-locking worm provides pallet hold at any position when wrapping cycle is paused. Y2 4-pole 0.75 to 1.5 kW.