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Hydraulic Rescue Spreader

Product

Overview

A hydraulic rescue spreader, commonly called the "jaws of life," is a powered extrication tool that forces apart, pulls or crushes wrecked vehicle structure to free trapped occupants. This unit is fully self-contained and battery-powered, carrying its own motor, pump and reservoir so it needs no external power unit or umbilical hoses. Two forged arms pivot on a center bolt; driven by a hydraulic cylinder, they generate tens of kilonewtons of force to pry open doors, push back dashboards and spread crushed sheet metal.

The working head is the Spreader Arm Assembly assembly, a pair of forged aluminium-bronze arms with replaceable serrated tips on a high-tensile pivot bolt. Force is delivered by the Hydraulic System, a high-pressure cylinder, directional control valve and relief valve fed from a bladder reservoir. Pressure is generated by the Pump Unit, a brushless motor turning a two-stage pump with an accumulator. The Motor Controller commutates that motor with overload protection, drawing from the removable Battery Pack. The operator works the Control Handle, a pistol grip with a deadman trigger and proportional flow valve, while the Work Light Module illuminate the scene.

How it works

Pressing the deadman trigger spins the brushless motor, which drives the two-stage pump. The first gear stage delivers high flow at low pressure to close the gap quickly with little resistance; once the tips meet structure and resistance rises, the tool automatically shifts to the radial piston stage, trading speed for the full system pressure of around 720 bar. The control handle's proportional valve routes fluid to either side of the cylinder piston, and a toggle linkage converts the piston's short stroke into a wide 32-inch arm spread. The cylinder force multiplied through the arm geometry yields up to 147 kN at the spreading tips. A relief valve caps peak pressure to protect the tool, and releasing the deadman trigger stops the motor and pump instantly, freezing the arms in position under load.

Bill of materials for Hydraulic Rescue Spreader

11 top-level lines as of r91893
# Item / sub-assembly Part no. Qty/assy Ext. qty Parts Type
1 Spreader Arm Assembly 4 parts jaws-of-life-spreader-arms 1× 1 0 assembly
2 Hydraulic System 7 parts jaws-of-life-hydraulic-system 1× 1 0 assembly
3 Pump Unit 4 parts jaws-of-life-pump-unit 1× 1 0 assembly
4 Motor Controller 5 parts jaws-of-life-controller 1× 1 0 assembly
5 Battery Pack 4 parts jaws-of-life-battery-pack 1× 1 0 assembly
6 Control Handle 3 parts jaws-of-life-control-handle 1× 1 0 assembly
7 Work Light Module 3 parts jaws-of-life-work-lights 1× 1 0 assembly
8 Carry Handle jaws-of-life-carry-handle 1× 1 · part
9 Pressure Relief Vent jaws-of-life-pressure-relief 1× 1 · part
10 Wire Bundle wire-bundle 1× 1 · part
11 Fastener Set fastener-set 2× 2 · part

351-word article