US 2113444 A
Description (OCR text may contain errors)
April 5, 1938. ERICKSON 2,113,444
VIBRATING MOTOR Filed Sept. 26, 1936 Patented Apr. 5, 1938 UNITED STATES PATENT OFFKIE Prentis E. Erickson, Minneapolis, Minn., assignor to James B. Bradshaw, Minneapolis, Minn.
Application September 26, 1936, Serial No. 102,782
My invention relates to vibration producing apparatus and particularly to apparatus for imparting vibration to a vibratory tool.
According to common practice many vibratory tools are driven by followers reciprocated by cams, by cranks or eccentrics connected to the tool by connecting rods, or by armatures of electric buzzer devices. All of such tool driving means produce vibratory movement of a substantially reciprocatory or rectilinear nature and also are subject to more or less wear which, after a time, tends to render the device excessively noisy.
A general object of my invention is to provide apparatus for imparting to a vibratory tool a motion including lateral as well as projective and retractive components of movement.
Another object of. my invention is to provide such vibratory tool driving apparatus of a rotary nature and yet of such construction as to obviate the need for motion converting means such as cam followers, connecting rods and the like.
A more specific object is to provide a vibration producing mechanism utilizing an eccentrically rotating Weight as the vibration producing element.
Still another object is to provide such mechanism wherein a resiliently supported motor is vibrated as a unit by an eccentric weight carried by the shaft of the motor.
A further object is to provide such apparatus of simple, rugged, compact, inexpensive and relatively wear-free construction.
These and other objects and advantages of the invention will more fully appear from the following description made in connection with the accompanying drawing, wherein like reference characters refer to the same or similar parts throughout the various views, and in which:-
Fig. 1 is a top view of an apparatus incorporating an embodiment of my invention,
Fig. 2 is a side view,
Fig. 3 is a front view, and
Fig. 4 is a sectional view taken along the line 44 of Fig. 2 as indicated by the arrows.
Referring to the drawing, I have illustrated my invention by showing an embodiment thereof incorporated in a scalp massaging device.
Essentially, my vibration producing apparatus consists of a member journalled in a suitable bearing element so as to be rotatable about a predetermined axis, said member having a center of mass disposed eccentrically of said axis and said bearing element being mounted on supporting means therefor of a yieldable nature so as to be resistingly permissive of lateral displacement of said bearing element and said member. Rotation of the eccentrically weighted rotatable member of such a combination will cause said yieldably supported bearing element to non-rotatively move in an annular path whereby an object connected to said bearing element will be vibrated. A manner in which the above broadly described essential elements may be embodied in a scalp massaging device is as follows.
The illustrated device includes a handle 5, having a radially enlarged portion or head 5a at its forward end carrying forwardly projecting parallel similar extensions 5bspaced from and at respectively opposite sides of the longitudinal axis of the handle 5. The handle 5, head Ea and extensions 5b comprise a support for elements to be described.
Structure including a member journalled in suitable elements is supported from the above described support between and inwardly spaced from the extensions 5b thereof. Preferably the supported structure consists of an electric motor M having a casing or frame 6 and an armature shaft 1. The motor M is supported from the extensions 5b in a manner permissive of movement of the motor M in directions radial thereof relative to the extensions 512. An endless band 8, of elastic material such as rubber, encircles the extensions 51) and the motor M so as to bear against the outer sides of the extensions 5b and points at right angles thereto on the periphery of the case 6 of the motor. The band 8 is secured to the extensions 51) and the motor case 6 at its points of contact therewith by suitable means such as the screws 9 and ID. If. desired washers H and I2 may be placed between the heads of the respective screws 9 and I0 and the band 8.
A spacing block l3, formed of elastic and resilient material such as sponge rubber or the like, is interposed between the handle head 5a and the rear end of the motor M.
To form a motor driven vibration producing unit, an element l4, preferably of cylindrical form and constructed from relatively heavy material, is eccentrically mounted on the motor shaft 1, as shown in Fig. 4, whereby the rotating parts of the motor M and the element I4 together comprise a member having a center of mass disposed eccentrically of the axis of rotation of. such member. The axis of rotation referred to obviously consists of the longitudinal axis of the motor shaft 1 which is, in a well known manner,
confined to rotation about such axis by shaft bearings (not shown) of conventional form included in the structure of the motor M in accordance with common practice.
A cup-like enclosure or housing l5, having a radially outwardly projecting annular flange Ia thereon, is placed over the eccentrically mounted weight element l4 and shaft 1 in enclosing and spaced relation thereto and is mounted on the front end of the casing 6 of. the motor M by suitably securing the flange in to the motor M as by means of nutted studs I512. The outer end of the enclosure l5 projects a short distance beyond the front or free ends of the extensions 5b and carries a centrally located forwardly projecting boss I5c. A strap 16, of elastic material such as rubber, has an apertured medial portion fitting closely about the periphery of the boss I50 and secured at its ends to the outer ends of the respective extensions 5b by suitable means such as the screws IT.
The band 8 and strap It constitute elastic connections between the motor M and the extensions 5b of the supporting structure such as to restrain the case 6 of the motor M from bodily rotation through any appreciable angle and yet resistingly permit deflection of the motor M within limits in any direction substantially normal to the axis of the motor shaft 1. With such yielding supporting means for the motor, operation of the motor and consequent rotation of the eccentric weight element M will result in a reaction tending to move the motor M bodily in an annular path generally normal to the shaft '1. Such movement of the motor M is, of course, not accompanied by rotation of the motor case 6 about the axis of the shaft 1. The motor M and the housing l5 move together and, in effect, constitute a single body moving annularly as described relative to the motor M.
Means is provided for connecting the above mentioned annularly moving body to any object to be vibrated. To this end an arcuate plate l8a, on which a depending, externally screw-threaded attachment stud I8 is mounted, is secured to the lower side of the enclosure l5 as shown in Fig. 4.
To illustrate one application of my vibration producing apparatus to a vibratory tool or appliance, a scalp massaging appliance S is shown screw threadedly mounted on the attachment stud [8 in operative relation therewith. The massaging appliance S is substantially the same as that shown in my U. S. Patent No. 2,049,434 on Scalp massaging apparatus issued August 4, 1936, and includes a spider-like series of resilient fingers l9 having rubber coverings Mia and.
mounted on the flange 20a of a flanged internally screw-threaded sleeve 20 adapted for mounting on the stud it of my device as shown. Curved elements 2i formed into hooks 2la at their outer ends are secured at their inner ends to the flange 20, as shown and are adapted for attachment thereto of a suitable retaining strap passing under the chin of a person on whose head the appliance S is disposed.
The motor M is provided with an electric cord 22 extending through a suitable passage within and disposed longitudinally of the handle 5 and adapted to be connected to a source of electrical energy. A switch 23, conveniently mounted in the handle 5, is connected in the circuit of the cord 22 for use in turning the motor M on and off.
The motion applied to the appliance S by the annularly moving motor M is obviously such that the appliance will be vibrated both vertically and horizontally and will hence produce both a rubbing action and a varying pressure on the head of the user.
It is apparent that I have invented a novel, simple, compact, effective and inexpensive vibration producing apparatus wherein structure subject to wear and productive of friction is minimized and which is capable of producing vibration including components of vibratory motion in various directions.
While my vibration producing apparatus has been illustrated and described as applied to a scalp massaging appliance, it should be obvious that the apparatus is readily adapted for use with many other types of appliances and tools.
It Will, of course, be understood that various changes may be made in the form, details, proportions and arrangement of the parts, without departing from the scope of my invention, which, generally stated, consists in a device capable of carrying out the objects above set forth and in the novel parts and combinations of parts disclosed and defined in the appended claim.
What is claimed is:
Vibration producing apparatus comprising, a motor having a frame and a power delivery shaft projecting outwardly thereof, supporting structure for said motor, resilient means connecting said motor to said structure, an element mounted on said shaft and having a center of mass disposed eccentrically of said shaft, means secured to said frame and enclosing said element and said projecting portion of the shaft, and an element carried by said enclosing means and adapted to be connected to an object to be vibrated.
PRENTIS E. ERICKSON.