DKE-L3 Bending Machine Shearing Machine Laser Protection Anti-Hand-Pressing Device

The DAIDISIKE DKE-L3 series laser safety protection device is a specialized anti-hand-crushing protector designed for press brakes and shearing machines, aimed at preventing industrial accidents such as finger or arm injuries during metal processing. It is a laser AOPD: instead of an area light curtain across the front of the machine — impractical where the operator must hold the workpiece against the tooling — three laser beams are carried on the ram so that the guarded zone is the point of operation itself.

The product is of separate construction: a transmitter and a receiver mounted on either side of the ram, projecting three laser beams E1, E2 and E3. The E1 beam is set 3 mm below the tool tip, so during the high-speed closing stroke any object such as a finger must break the protective band before it can reach the punch, triggering a stop. The device has three operating modes, including a box/tray bending mode that keeps guarding active when the raised flanges of a box-shaped part would otherwise obstruct the beams, plus a protection on/off switch.

The advantages of this device lie in its short 5 ms response time and 10 mm resolution, together with a dedicated FA (fast-close enable) output that lets the ram close at high speed whenever the protective band is clear, and two selectable slow-speed inputs for the pressing phase. This preserves cycle rate instead of forcing the whole stroke to run at slow speed. Mounting brackets are matched to the machine structure — contact the factory with your ram and tooling details.

In practical applications, DKE-L3 addresses common risks such as operator negligence, inconsistent workpiece placement rhythm or fatigue work. The light source is an infrared laser of approximately 780 nm, Class 1 under the IEC 60825-1 classification during documented normal operation. This classification does not replace the installation, maintenance or fault-state precautions in the supplied manual. The housing is IP65-rated and the device runs on a DC 12–24 V supply (tolerant of 12–26 V), taken directly from common press brake control power. Housing material, dimensions, operating temperature range and current draw are not published in the current factory data — contact the factory if your specification requires them.

DKE-L3 Series Specification Table

DKE-L3 Series Technical Parameters

The technical parameters of DKE-L3 are based on the laser AOPD principle, emphasizing detection close to the tool tip and fast response. Key parameters include:

• Laser Wavelength and Class: Infrared laser of approximately 780 nm, Class 1 under the IEC 60825-1 laser classification — eye-safe on the shop floor, with no visible light radiation.
• Protection Zone Configuration: Three beams (E1/E2/E3) are carried on the ram and form a protective band directly beneath the punch, with E1 set just 3 mm below the tool tip, so the guarded area follows the tool instead of blocking the operator's hands.
• Response Mechanism: When a beam is broken the receiver drops its dual OSSD safety outputs (pins 8 and 9) within a 5 ms response time, giving the press brake control the stop command.
• Fast-Approach Logic: A dedicated FA (fast-close enable) output on pin 7 permits high-speed ram closing while the protective band is clear; two selectable slow-speed inputs (pins 5 and 6) handle the pressing phase.
• Interfaces: Transmitter on a 9-pin aviation plug, receiver on a 15-pin aviation plug, with an integrated foot-switch input on pin 4. There is no RS485, RS232 or analogue interface.
• Beam Set-up: 4.5 mm beam profile, adjustable within a 15 mm window, allows fine set-up to each tooling configuration after a tool change.
• Enclosure: IP65-rated housing and a wide DC 12–24 V (12–26 V tolerant) supply that runs directly off common press brake control power.

These parameters describe the device interface; the achieved protection depends on the machine stopping time, mounting geometry, control system and validation of the complete safety function.

DKE-L3 Series Working Principle

The working principle of DKE-L3 is laser beam interruption detection at the point of operation. The transmitter is mounted on one side of the upper die slider and emits three parallel laser beams (E1, E2, E3) that form a thin protective band beneath the punch, with E1 set 3 mm below the tool tip. The receiver is mounted opposite, up to 15 m away, and monitors the integrity of the beams.

When the press brake or shearing machine's upper slider descends at high speed, the protective band moves with the slider, so the guarded zone always tracks the tooling. If an operator's finger or another object enters the band, a beam is blocked and the receiver no longer sees the complete signal. Within a 5 ms device response time the receiver drops both OSSD outputs (pins 8 and 9), requesting the machine control to execute its validated stop or safe-slow-speed function.

The workflow is as follows:

1. Set-up: Align transmitter and receiver on the ram and adjust the 4.5 mm beam band within its 15 mm window so that E1 sits 3 mm below the tool tip for the fitted tooling.
2. Fast approach: While the protective band is clear, the FA output on pin 7 enables high-speed closing of the ram.
3. Trigger response: On beam interruption the dual OSSD outputs (pins 8 and 9) switch off within 5 ms and the machine control stops slider movement.
4. Pressing phase: The two slow-speed inputs (pins 5 and 6), together with the foot-switch input on pin 4, control the bending stroke at safe slow speed.
5. Mode selection: Three operating modes, including box/tray bending mode, plus a protection on/off switch, adapt the guarding to the workpiece being formed.

The receiver connects through a 15-pin aviation plug and the transmitter through a 9-pin aviation plug. The device has no RS485, RS232 or analogue interface — the interface to the machine is the dual OSSD safety outputs plus the FA and slow-speed signals.

Specs reviewed by Engineer Cai, Senior Application Engineer. See certificates.