US 3440681 A
Description (OCR text may contain errors)
Apnl 29, 1969 w. H. HIXSON E 3,440,681
VACUUM CONTROL FOR ELECTRIC HAIR CLIPPER HAVING AN ASSOCIATED VACUUM SYSTEM Filed March 6, 1967 II II II II II II IA tn I I a I N VE N TOIQS ZUz'Ibur' H h'z'xson yolzn .1 ZZJa/zl M W4 M) fiwwii/ 41 95 Clfffora H Jordz'rzy United States Patent Oifice 3,440,681 Patented Apr. 29, 1969 3,440,681 VACUUM CONTROL FOR ELECTRIC HAIR CLIPPER HAVING AN ASSOCIATED VACUUM SYSTEM Wilbur H. Hixson, Monroe, Wis., and Clifford H. Jordmg and John F. Wahl, Sterling, Ill., assiguors to Wahl Clippper Corporation, Sterling, Ill., a corporation of Illinois Filed Mar. 6, 1967, Ser. No. 620,764 Int. Cl. B26b 19/44; A471 9/32, 9/00 US. Cl. 15-339 2 Claims ABSTRACT OF THE DISCLOSURE An electric hair clipper having an associated Vacuum system for removing cut hair during clipper operation. The vacuum system includes a duct located on the top of the clipper, the forward end of the duct positioned adjacent the clipper blades and the rearward end adapted to be connected to a source of subatmospheric pressure. A wall of the duct is provided with an opening, and a plate mounted for sliding movement engages the wall at this opening. The plate in one position of adjustment closes the opening, and in other positions of adjustment uncovers portions of the opening to provide venting to atmosphere and consequent change in pressure conditions within the duct. The sliding plate is located for easy manipulation during use of the clipper, and enables the operator to control in a continuous manner the intensity of air flow through the duct as required by the clipping operation being performed.
BACKGROUND OF THE INVENTION This invention falls in the field of electric hair clippers, and more particularly in the field of electric hair clippers which are provided with an associated vacuum system for removing hair as it is cut by the clipper blades. The vacuum system includes a duct extending along the top of the clipper, the duct having its forward end adjacent the clipper blades. The invention contemplates a continuously adjustable vacuum control for the system, whereby the operator easily may manipulate the control while the clipper is in use to regulate the flow of air through the system in accordance with the requirements of the clipping operation being performed.
When a clipper with an associated vacuum system is operated to cut hair to a comparatively long length, in which case the clipper is spaced a substantial distance from the head, neck, or ears of the customer, it usually is desirable to have a maximum flow of air through the vacuum system for purposes of hair removal. However, when the clipper is used to cut the hair to short length, as in the region of the neck and ears, a maximum flow of air through the system is undesirable for the reason that portions of skin tend to be drawn across the forward duct end and into the clipper blades, producing discomfort and possible skin cutting. Accordingly, it is desirable to be able to control the intensity of the air flow through the system. The air flow, of course, would be reduced in intensity for close cutting.
SUMMARY OF THE INVENTION A wall of the vacuum duct on the top of the clipper is provided with an opening, preferably of T-shape. A slider plate engages the duct wall at the opening. In one position of adjustment the slider plate seals the opening, and in other positions of adjustment it uncovers portions of the opening to provide venting to atmosphere in varying degree. The size of the opening uncovered by the slider plate, of course, controls the intensity of air flow within the duct. Means are provided for mounting the slider plate on the duct wall, and for applying alight bias between the plate and wall so that frictional forces will hold the pate in a set position. The invention is extremely inexpensive to install and easy to operate, compared, for example, with an arrangement for varying the magnitude of the sub-atmospheric pressure at the pressure generator, and is equally elfective in operation.
BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a perspective view of an electric hair clipper having an associated vacuum system embodying the vacuum control of the invention.
FIG. 2 is a side elevational view of the clipper shown in FIG. 1.
FIG. 3 is an enlarged side elevational view, partly in longitudinal section, showing details of the vacuum control, certain irrelevant clipper features being omitted.
FIG. 4 is a fragmentary top plan view showing further details of the control.
FIG. 5 is a bottom view of the portion of the duct wall shown in FIG. 4.
FIG. 6 is an enlarged longitudinal sectional view on line 6-6 of FIG. 4.
FIG. 7 is an enlarged transverse sectional view on line 77 of FIG. 4.
DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the drawing, the vacuum control of the invention is incorporated in an electric hair clipper 10 having an associated vacuum system 11. Clipper 10 has conventional stationary blade 12 and movable blade 13 driven by a suitable motor generally designated 14 (FIG. 3).
Vacuum system 11 includes a duct 15 on the top of clipper 10, as best shown in FIG. 3. The forward open end 16 of duct 15 is positioned adjacent the clipper blades 12, 13, and the rearward end 17 of the duct is adapted to be connected to a source of sub-atmospheric pressure (not shown). The sub-atmospheric pressure applied to rearward end 17 of the duct 15 causes a fiow of air through the duct from front to rear, as indicated by the arrows 18. This air is effective to remove hair cut by the clipper blades.
As best shown in FIGS. 37, one wall of duct 15, preferably upper wall 20, is provided with an opening 25. In preferred form, opening 25 is T-shaped, the head 26 of the T positioned forwardly in the duct wall and the stem 27 (FIG. 5) of the T extending longitudinally of the duct. As shown, opening 25 is more or less centrally located in duct wall 20, a position particularly convenient for manual manipulation of the control.
A slider plate 30 (all figures) engages upper duct wall 20 at opening 25. As will be seen, slider plate 30 in one position (forward) of adjustment seals opening 25, and in other or rearward positions of adjustment uncovers portions of opening 25 to provide venting to atmosphere.
Means are provided for mounting plate 30 on duct wall 20 for sliding movement, and in the form of the invention shown, the mounting means includes an elongated rib or reduced boss 35 on the bottom of plate 30, the bottom surface of the plate engaging duct wall 20. Rib or boss 35 has a width corresponding to that of stem 27 of the opening, and thus it cooperates with the sides of the opening to provide a guide for plate movement. The thickness of rib or boss 35 corresponds to that of duct wall 20, as best shown in FIGS. 6 and 7.
The illustrated plate mounting means also includes a portion 36 (FIGS. 5-7) protruding from boss 35 into the interior of duct 15. A spring means 37 is secured to protruding portion 36, and it bears against the under side of duct wall 20, thereby providing a light bias and consequent frictional relation between plate 30 and the duct wall. As shown, spring 37 is a resilient washer in pressed fit relation with protruding portion 36.
As previously mentioned, during use of the clipper in cutting hair to the longer lengths, slider plate 30 normally is pushed all the way forwardly to seal opening 25, thereby maximizing the flow of air through the vacuum system for desired hair removal. When the clipper is being used for close cuttings, plate 30 is moved rearwardly to a greater or less extent, thereby closely controlling in a continuous manner the flow of air through the vacuum system to avoid discomfort to the customer, or possible skin cutting. The problem of loose skin sealing across the open forward duct end is greatly reduced or eliminated, as opening the adjustable vacuum control prevents the build up of excessively low pressure. This allows the clipper to be moved smoothly across the skin for an evenly tapered haircut.
From the above description it is thought that the construction and advantages of this invention will be readily apparent to those skilled in the art. Various changes in detail may be made without departing from the spirit or losing the advantages of the invention.
Having thus described the invention, what is claimed as new and desired to secure by Letters Patent is:
1. In an electric hair clipper having an associated vaccum system for removing cut hair wherein said vacuum system includes a duct on the top of the clipper, the forward end of the duct positioned adjacent the clipper blades and the rearward end of the duct adapted to be connected to a source of sub-atmospheric pressure, a continuously adjustable vacuum control for said vacuum system comprising:
a duct wall having a T-shaped opening therein remote from the forward end of the duct, the stem portion of said opening extending longitudinally of said wall;
a manually actuated slider plate engaging said duct wall at said T-shaped opening, said slider plate in one position of adjustment sealing said opening and in other positions of adjustment uncovering the head portion of said T-shaped opening in whole and in part to provide venting of the duct to atmosphere; means mounting said slider plate on said duct wall for sliding movement, said means including an elongated boss on said slider plate extending into said stem portion of said opening and cooperating with the sides of said opening stem portion to provide a guide for plate movement, said boss having a reduced portion protruding into the duct interior; and spring means secured to said reduced portion of said boss and bearing against the underside of said duct wall, providing a light bias and consequent frictional relation between said plate and said wall, whereby said slider plate is secured in all set positions and movable only in response to manual manipulation. 2. The combination of claim 1 wherein said spring means is a resilient washer in pressed fit relation with said protruding reduced portion of said boss.
References Cited UNITED STATES PATENTS 2,176,139 10/1939 Lofgren. 3,331,130 7/1967 Ligon 30-133 3,348,308 10/1967 Andis 30 133 2,748,472 6/1956 Sheley et a1. 30-133 2,811,738 11/1957 Gall 1S375 XR FOREIGN PATENTS 564,060 9/ 1958 Canada.
1,086,685 8/ 1954 France.
ROBERT W. MICHELL, Primary Examiner.
s. c1. X.R. 15-421; 30 133