| 摘要 |
<p>An electrically heated excising or cutting tool for cutting rubber, plastic, and the like includes a handle carrying at one end a cutting blade of flat resistive material through which current flows to produce heat. The blade is substantially U-shaped with limbs having free ends clamped to contact pieces on the handle connected to the poles of a power supply. The blade is bent at right angles to the plane of the flat material in the region between the free ends of the limbs and the bight portion of the U-shaped blade to define a cutting region having a first limb disposed in a cutting direction from the second limb. The first limb is reduced in cross-sectional area at the bend to increase the production and concentration of heat in the cutting region to counteract the increased heat dissipation in the cutting region caused by the accumulation of excised material thereat. A cooling device is provided on the handle for cooling the parts of the blade away from the cutting region to reduce the transfer of heat to the handle and to simultaneously result in an increase in heat generation in the cutting portion of the blade due to the increase in electrical resistance in that region. The contact pieces are provided with openings to further reduce heat transfer to the handle.</p> |
