CA2046751A1 - Rescue cutter - Google Patents

Abstract

(ss. 21, 31, 34 and 142) ABSTRACT

In emergency rescue activities involving automobile accident victims, rescue cutters are frequently used for the extraction of victims trapped in vehicles. The rescue cutters available today are expensive large industrial hydraulic powered devices not accessible to all emergency response personnel, in that they require specialized training and take time to transport and set up at an accident site. This invention is an inexpensive, light weight, manual rescue cutter which can be operated by a single individual. Low cost, ease of use, safe design, and small size make it readily accessible by all emergency response personnel, including fire fighters, policemen, and ambulance operators. The invention features a cutting handle consisting of a case hardened steel blade fastened to a fixed handle made from mild steel box section, and a moving handle fastened to a connecting arm which in turn is bolted to a moving blade as well as an adjusting screw in the fixed handle.

Description

SPECI~ICATION

This invention relates to a mamlally operable tool for cutting steel to free accident victims trapped in vehicles as a result of automobile accidents.
Fire fighters, policemen, ambulance operators and other emergency response personnel all take part in emergency rescue activities involving automobile accident victims. Rescue cutters for the extraction of accident victims trapped in crashed vehicles are available as large and expensive industrial hydraulic powered devices requiring skilled operators. In addition, the equipment is generally not easily accessible due to its size and complexity and must be called for and transported to accident sites, in some cases along with its operators. Although highly effective, emergency rescue with such devices is relatively time consuming, expensive, and cumbersome.
These disadvantages can be overcome by providing a simple, inexpensive, lightweight, and manuaily operated rescue cuKer. The invention features a fixed handle aKached to a hardened steel blade, and a moving handle fastened to a moving blade through a connecting arm which is also attached to an adjusting screw in the fixed handle. Depending on the setting of the adjusting screw and the pressure exerted in pushing the handles together, the manual rescue cuKers can achieve the same amount of cuKing pressure at the tip of the blade as can the hydraulic cuKers. The manual rescue cutters can be operated by any personnel with minimal training, and are small enough to be conveniently carried in all emergency response vehicles.
In drawings which illustrate an embodiment of the invention, Figure 1 is a top plan view of this embodiment, and Figure 2 is an elevation partly in section of the embodiment.

The tool illustrated comprises a ~Ixed handle 1 constructed from steel box section bolted to a case hardened steel fixed blade 2. A slot is cut in the wall of the fixed handle 1 to allow the free movement of the connecting arm 3, and to prevent the end of the connecting arm 3 from falling out of the fixed handle 1.
The connecting arm 3 is cut from steel plate, and is shaped at the top with a cam 3a which allows a straight line to form (when the handles are pushed together) between the pivot point of the connecting arm 3, the top of the case hardened steel moving blade 4 to which it is bolted, and the point of the adjusting screw 5. In addition7 the cam 3a provides a safety feature by stopping the handles from closing together onto the operator's fingers.
The moving handle 6 is constructed from steel box section and has part of the inside wall cut away to allow the connecting arm 3, to which it is bolted, free movement. The moving handle 6 is bent and a small section of the outside wall is cut away at the end to allow free movement of the moving blade 4, and for the same reason a semi-circle is milled into the fixed handle 1.
The moving blade 4 is bolted to the fixed blade 2, and a spring 7 extends from a hole drilled into the moving blade 4 to a hole drilled in the fixed handle 1 to hold the blades apart.
The adjusting screw 5 is machined from a length of round steel stock to produce a square threaded rod.
The adjusting screw 5 is located in the fixed handle 1 and held by two supporting blocks 8 within the handle. A cup 3b is welded to the connecting arm 3 against which the adjusting screw 5 can press. The turning handle 9 is fastened to the end of the adjusting screw 5.
The tool is assembled with steel bolts, packing washers and tightened with lock nuts. All bolt holes tightly fit around the shank of the bolts to minimi~e any free play which will impair the performance of the tool.
The tool operates on the four-bar chain force model, which has four dependent links with one bar fixed as a boundary condition. A force applied to the handles of the tool results in a magnifled force through the moving blade. The adjusting screw head and the fixed blade are the pivots that cause the moving blade to close relative to the fixed blade. The cutting force is dependent on the length of the handles and the magnitude of the force applied by the operator.

Claims (5)

1. A manually operable cutting tool which operates on the four-bar chain force model, which has four dependent links with one bar fixed as a boundary, to magnify the force applied at the handles to the cutting blades.

2. A tool as defined in claim 1 to be used in the extraction of accident victims trapped in vehicles involved in automobile accidents.

3. A tool as defined in claim 1 or claim 2, in which a cutting blade is fastened to a fixed handle, and bolted to a moving cutting blade which is in turn bolted to a moving handle and a connecting arm connected to the fixed handle.

4. A tool as defined in claim 1 or claim 2 or claim 3, in which the width of the opening between the cutting blades when the handles are pulled apart depends on the setting of an adjusting screw in the fixed handle.

5. A tool as defined in claim 1 or claim 2 or claim 3 or claim 4, in which a spring pulls the cutting blades apart from one another.