JPS64305Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to keeping the handle portion of a power tool held by an operator warm.

Conventional power tools generally have a structure in which cooling air from the motor is sucked in from the handle side and discharged to the tip tool side. However, in the case of power tools that are often used intensively during the cold period of winter, such as electric drills for cultivating shiitake mushrooms (shiitake mushroom drills) and electric chain saws, cold air is sucked in from the handle side.
Because the handle is constantly cooled, it is still cold even if the operator takes measures to protect himself from the cold, reducing work efficiency and causing problems such as Raynaud's syndrome in some workers who have used it for a long time. . Conventional power tools have taken measures to reduce vibration to some extent, but no measures have been taken to deal with low temperatures.

The purpose of this invention is to solve the above-mentioned problems of the conventional technology, to keep the handle part held by the operator warm,
The aim is to improve work efficiency and prevent occupational diseases such as Raynaud's syndrome.

This invention focuses on the shared voltage of the stator while the motor is operating, and supplies the low voltage generated at both ends of the stator windings to the heating element installed in the handle, thereby keeping the handle warm. This design was designed to improve safety since the body's voltage is low.

An embodiment of the present invention will be explained using a shiitake mushroom drill as an example.

In the figure, a stator 1 and a rotor 2 are housed inside an outer frame 7. A handle portion 3 that is gripped by an operator is formed at the rear of the outer frame 7.

During operation of the motor, the voltage generated across the stator windings is as low as about 20% of the motor supply voltage. As shown in the circuit diagram of Fig. 3, using the voltage generated at both ends of the stator winding as a power source, a heating element 6 such as a stainless steel plate is installed along the inner peripheral surface of the handle.
is installed. As shown in FIG. 2, this heating element is covered with an insulator 4 such as silicone rubber. When the temperature of the heating element rises and the outside temperature also rises, the operator holds it and when the upper limit temperature is reached, the circuit of the heating element is turned on by the switch 5 installed in a position that can be operated from the outside. It is arranged so that it can be opened and closed.

Further, by extracting the power supplied to the heating element from a part of the stator winding, it is possible to supply a voltage even lower than that of this embodiment, depending on the turn ratio of the stator winding.

According to the present invention, the voltage generated at both ends of the stator winding during motor operation is used as a power source, and a heating element is placed in the handle grip to keep it warm. This improves safety and improves work efficiency during cold seasons. Occupational diseases such as Raynaud's syndrome can be prevented.

[Brief explanation of the drawing]

FIG. 1 is a partially longitudinal front view of an electric drill showing this embodiment, FIG. 2 is a sectional view taken along line AA in FIG. 1, and FIG. 3 is a circuit diagram. In the figure, 1 is a stator, 2 is a rotor, 3 is a handle, 4 is a heating element, 5 is a switch, and 6 is an insulator.

Claims (1)

[Scope of utility model registration request] An electric motor includes a stator held inside a frame, a rotor rotatably supported by the frame and to which a cooling fan is fixed, and a handle held by an operator on a part of the frame. 1. A power tool having a handle part, wherein a heating element is provided in the handle part, and power for the heating element is supplied from a low voltage power source generated at both ends of the winding of the stator.