This invention relates to hair clippers, and more particularly to motor vibration and noise dampening for hair clippers driven by a rotary motor with an eccentric cam mechanism converting rotary motion into linear motion of a reciprocating blade.
Many hand held tools are designed to hold or support a motor in a rigid housing around the motor's front and rear motor bearings. To suppress vibration transferring to the housings, a thin rubber collar is used around the circumference of the bearings. For additional vibration reduction, a piece of sponge rubber is often used between the motor and housing under light compression. However, if the housing is significantly larger than the motor (creating a large dead air space) or the motor has significant clearance between the shaft and bearing, the motor vibration tends to resonate inside the housing causing amplified noise. Both vibration and noise are undesirable.
Vibration and noise occur in rotary motor hair clippers, where an eccentric cam drives a blade along a linear reciprocating path. The eccentricity of the cam causes resonant frequencies at the points of contact between the motor and the housing, and transfers energy into vibration and noise that the user feels while the hair clipper is in use.
Thus, there is a need for vibration dampening for hair clippers that use rotary motors to reduce motor and housing vibrations of the hair clipper.
There is also a need for vibration dampening for hair clippers having rotary motors that better reduce noise generated by operation of the hair clipper.
In keeping with one aspect of the invention, a hair clipper has a base structural housing with a blade set operably secured thereto. The blade set has a stationary blade and a reciprocating blade. The base structural housing also has at least one support for a rotary motor. The rotary motor has a shaft extending between a front bearing and a back bearing of the motor, and the shaft has a cam near the front bearing for driving the reciprocating blade.
A flexible motor vibration damper fits over half of the motor, and a motor cover is secured to the base structural housing over the vibration damper. A secondary housing cover is secured to the base structural housing over the motor cover.
The above mentioned and other features of this invention and the manner of obtaining them will become more apparent, and the invention itself will be best understood by reference to the following description of an embodiment of the invention taken in conjunction with the accompanying drawings, in which:
As seen in
A blade set 14 includes a stationary blade 15 and a reciprocating blade 16. A blade depth adjuster 17, a motor switch 18 and a clipper hanger hook 19 are provided. A power source such as a battery or line cord and appropriate wiring (not shown) are also provided.
A rotary motor 20 has a shaft 22 (
Turning briefly to
Returning to
A flexible motor vibration damper 40 fits over the cover side 36 of the motor 20. The damper 40 is preferably made of flexible rubber or plastic material that absorbs vibration and reduces noise.
The vibration damper 40 has an inside surface 42 (
On the inside surface 42, the vibration damper 40 has a plurality of spaced ribs 46 (
The vibration damper 40 also has a raised portion 50 (
A plurality of openings 56 can be provided in the vibration damper 40. Heat from the motor 20 is dissipated through the channels 48, the openings 56 and corresponding openings 59 in a motor cover 60 (
The motor cover 60 is secured to the base structural housing 12 by a plurality of fasteners 62. The motor cover 60, which is preferably rigid, is secured to the base structural housing 12 over the vibration damper 40, compressing the damper 40 over the motor 20. The motor cover 60 includes an opening 64 through which the protrusion 50 on the top of the vibration damper 40 passes. The motor cover 60 also has side surfaces 61, 63 that cover the motor face flanges 45, 47 and openings for the fasteners 62.
The vibration damper 40 includes a pair of fingers 76 (
The secondary housing cover 13 is secured to the base structural housing 12 by fasteners 82 (
Assembly of the hair clipper 10 can be best understood with reference to
The blade set 14 is also secured to the base structural housing 12 with suitable fasteners 90. In
Referring again to
The advantages of this invention are now apparent. Both vibration and noise are reduced as compared with the vibration and noise generated by conventional hair clippers.
While the principles of the invention have been described above in connection with specific apparatus and applications, it is to be understood that this description is made only by way of example and not as a limitation on the scope of the invention.