US2281753A - Motor - Google Patents

Description

May 5, 1942. G. DALKowlTz MOTOR Filed Oct. 1, 1937 2 Sheets-Sheet 1 '338 Moo 92 INVENTOR Go fre Dalkowlz BY @AA/l- ATTORNEY May 5, 1942 G. DALKowl'rz 2,281,753

MOTOR Filed Oct. l. 1957 2 Sheets-Sheet 2 TEV. Z2 4.-;

Patented May 5, 1942 UNITED STATES PATENT OFFICE MOTOR Application October 1, i937, Serial No. 166,726

8 Claims.

In one of its aspects, this invention relates to dry shaving apparatus whereby the shaving operation is effected without any preparation of the skin and hair as by the application of soap, shaving cream and the like and in another of its aspects relates to a motor particularly intended for the operation of small tools or instruments of which dry shavers and hair clippers are examples.

Among the general objects of my invention is the provision of a device that is compact, eilicient in operation and low in manufacturing and maintenance costs.

Among the more particular objects of my invention may be mentioned the provision in a motor operated tool of an effective arrangement of the parts thereof; the provision in a motor operated tool of an improved motor; the provision in an electric motor of the magnetic type, of improved make and break means; the provision in a motor of improved means for mounting the rotor thereof; the provision in a motor operated tool, the motor oi' which has a time control operating device associated therewith, of improved means for operating said time control device and for transmitting movement from the motor to the tool; the provision in a motor operated tool, the motor of which is an electric motor of the magnetic type provided with a make and break device, of improved means for operating said make and break device and for transmitting motion from the motor to the tool; the provision in a dry shaver of a motor having improved means for transmitting power from the motor to the shaver head; the provision in an electric motor of the magnetic type of a make and break device comprising two sets of contacts and more particularly of two sets of contacts connected in series so that when the contacts of either set are 'separated the circuit will be broken; the provision oi' an improved casing for a motor; and the provision, in a casing for a motor, of improved means for mounting the motor in the casing.

For the attainment of these objects and such other objects as will hereinafter appear or be pointed out I have shown one invention in the drawings, in which:

Figure 1 is a plan viewof a dry shaver according to my invention. with a portion of the casing removed so as to expose the interior thereof;

Figure 2 is -a sectional view substantially on the irregular line 2--2 of Figure 2, looking in the direction of the arrows, and showing all portions of the device in place within the casing;

Figure 3 is a sectional view substantially on the irregular line 3 3 of Figure l, looking in the direction of the arrows; and

- Figures 4, 5 and 6 are sectional views respectively on the lines 4 4, 5-5 and 6-6 of Figure 1, looking in the direction of the arrows.

Referring now to the drawings for the details of my invention, it will be observed that my invention has been shown in an illustrative embodiment thereof as comprising an electric motor enclosed within a casing from one end of which protrudes an oscillating lever for causing movement of tool parts such as a shaver head (so indicated in dot-and-dash lines) while from its other end protrude terminals through which connection with a source of electrical energy may be made.

The motor is shown as of the magnetic" type and as comprising a laminated horseshoe-shaped field structure I0 of any suitable or preferred material, such as electrical steel, which has the property of becoming magnetized when subjected to the action of the electric current in a coil oi' insulated wire, such as shown at i2, and of losing its magnetism when the electric current is no longer allowed to pass through the coil, and this field structure I0 is provided with a pair of poles I4, I4, spaced from each other so as to provide a gap within which is positioned the armature I6, mounted on a shaft I8 for rotation therewith.

The field structure I0 and coil I2 are preferably of such dimensions and proportions that when they are enclosed in the casing, shown as comprising two sections numbered 20 and 22 respectively, the wholey may be conveniently grasped in the hand and serve as a handle in manipulating the dry shaver while shaving.

The casing section 20, which may be referred to as the lower section, since it is provided with mountings for holding the motor within the casing, is in the form of a thin shell of any suitable or preferred material, such for example as synthetic resin, which possesses the advantage of being 'an insulator and may be readily molded into the desired shape, and in order to impart strength to this shell and to afford portions of sufficient thickness to provide an anchorage for the motor and for the means to hold together the parts of the casing, I have shown the casing section 20 as provided with a pair of longitudinally extending ribs 24 and 26, as well as with bosses 28 adapted to receive suitable fastening means, and the section 20 is further shown as having a thickened portion 30 at its forward end provided with a recess within which is adapted to seat'the shaving head, indicated in dot-anddash lines at 32. Where the anchorages or other fastenings for uniting the casing sections take the form of screws, nuts to receive the same are conveniently molded into the material of the casing, as indicated in the drawings.

'I'he casing section 22 is shown as provided with a thickened portion 8l similar to portion 88 of the section 28 and also recessed to accommodate the shaving head 32, and is further shown as provided with tubular bosses 84 through which may pass screws 86 used to fasten the two casing sections together and it may also be provided with strengthening ribs similar to the ribs 24 and 26 of casing section 28.

In order to hold the field structure I6 in place within the casing section 28 I have shown fastening means, such as a pair of screws 38, one

passing through each of the legs of the ileld structure I l and anchored respectively in suitable means provided in the ribs 24 or 26 of the casing.

The armature I6, like the eld I8, is of any suitable or preferred laminated material, such as electrical steel, and is carried by an armature shaft 'I8 shown as journalled in a pair of members 42and '44 .disposed respectively-on op- -posite sides ofthe armature, and anchored to the poles I4 of the field structure Ill in any suitable or preferred manner, as by the rivets 46. In order not. to interfere with the functioning of the motor, which depends on thev magnetic action of the field on the armature, the members 42 and 44 are preferably made` of non-magnetic materiale of any suitable or preferred type, and

forv apurpose.- that will appear latex-this material should lpreferably be electrically insulating as well. y

A washer 48 is shown interposed between each member 42 and `44 and the armature, and as sunk into the end laminations of the amature. It

will be observedthat the washers 4II-serve thefunction among others of 4preventing rubbing ofthe armature against these members 42 and 44.

At one end thereof the armature shaft I8 is shown as provided with an eccentric 48, and this eccentric is shown as surrounded by a bushing 60 in slidable engagement with the walls of a slot 62 provided in one end 54 of an operating lever 66 pivotally mounted in the casing as byV means of the pin 68 passing through the leverand journailed within a pair of bushings 68, one on each side of the lever and carried respectively by spaced members 62 and 64 mounted on the casing section 28 as by means of screws 66 passing through both of said members 62 and 64 and anchored in the casing section 20, the- members 62 and 64 being shown as held in spaced relation by sleeves 68 surrounding the screws 66.

I'he lever 66 of the specific embodiment herein illustrated isI shown as made in three sections, one of which 64, already mentioned, is positioned above the amature and is provided with the slot 62, while another carries the pin 58, and extends out of the casing through an opening 69 therein, and is adapted to activate the shaving head 32 by means of its free end portion 68 that is adapted to extend into the shaving head and to cause movement of parts thereof as the lever 66 oscillates about the pin 58 as an axis, this oscillation being effected by the rotation of amature shaft I8 and the consequent movement of the eccentric 48 and bushing 68 within the slot 62 of the inner end of the lever 56, Be-

`cure this result of' preventing passage of cur'- rents through the lever into the shaving head it is not suicient to provide insulation only at this point, but insulation must be provided wherever the lever touches parts that are or may become electrically alive.

In order to keep bushing 60 in its place surrounding' the eccentric 48 I have shown a plate or disc, II4 mounted on the end of the shaft I8 and secured thereto by suitable or preferred means such as ascrew IIS.

The motor assembly further requires a make and break arrangement, whereby the electrical circuit consisting of the field coil I2 may be made and broken at appropriate times so as to give the timed magnetic impulses to the armature on which the operation of the motor depends. For this purpose I have shown by way of example, a pair of electrically conducting members 12 (visible most clearly in Figure 4) mounted one on each side of the member 42, as by rivets- 14 and whioh as already stated is made of velectrically non-conducting material in any suitable or preferred manner. One end of each of Said members I2A is illustrated as of U-shaped cont-our andas carrying a beador button 16 of material suitable for a contact for an electrical make and break. Adjusting means whereby the position of the contactv 16 may beA adjusted with a high degree of refinement is shown in the-form ofan adjusting screw I8 passing through the inner leg of the U-shaped portion of eachmember' 12, as well as through the other end portion thereof, and inv threaded engagement therewith and the nose of the screw 'I8 is shown as pressing against the outeg` contact carrying leg of the U-shaped portion. 'Bie latter is resilient or resiliently connected to the other portions of the member 12, so that it will always maintain contact with the nose of the screw 18, and as the screw is adjusted the contact will be correspondingly moved. Each contact 16 is opposed by a companion contact indicated at 86, and carried by a resilient or resiliently mounted electrically conducting member 82 that is shown as caried by an electrically conducting strip or plate 84 serving to electrically unite the members 82. The strip or plate 84 is conveniently mounted either by passing the screws 38, that hold the field within the casing, through the strip 84 so that it is clamped against the field under the heads thereof, or by mounting the same on a second strip or plate clamped against the field as just described or in any other preferred or desired manner. Whichever method is used it is obviously preferable that the strip or plate 84 be insulated from the eld structure so that the make and break system is insulated therefrom.

In the illustrated embodiment the making and breaking of the electrical circuits is shown as effected by means that cause separation of the contacts 88 and 16 at appropriate times. For

this purpose a tapper or cam 86 is shown as mounted on the portion 64 of lever 66, being secured thereto in any suitable or preferred manner as by rivets 66; and projecting portions thereof are adapted to strike against the members 62 and to cause separation of the contacts 16 and 66 as the eccentric 66 causes the lever portion 64, and consequently the cam 66, to move to one side or the other of itsmidposition.

It will be observed that electrical current is introduced into the motor through the terminals I6 and 62, shown as carried on an insulating plate 86 seating within grooves in the casing sections 26 and 22, as by connection thereof to a plug connected to a source of current.

It will be convenient in order to trace the electric circuits of the motor to consider the current as entering at the terminal 66 and from there passing through a lead 64 into the coil I2 through one terminal 66 thereof, and out of the coil I2 through the terminal 66 thereof and into the lead 89 from which it passes through the head |02 into the right hand member 12 (as seen in Figure 1) through the right hand contacts 16 and 60, through the right hand member'62, and through the strip 64 into the left hand member 62, and the left hand contacts 66 and 16 and left hand member 12, from which it passes through the leads |06 and lili into the terminal 62, which completes the circuit.

It will be observed that the circuit as just described is a closed circuit and presupposes a position of the eccentric 66 in which the cam 66 does not effect separation of either pair of contacts, that is the lever I6 must be in, or near its mid-position. When the circuit is so closed the field structure i will be magnetized and the armature i6 will move into bridging alignment with the poles I6 of the field structure. The eccentric I6 is positionally so related to the armature that as the latter reaches the aforementioned bridging position the cam 66 causes either one or the other of the pairs of contacts 66 and 16 to separate, and since these pairs of contacts are in series, separation of the contacts of either pair opens the motor circuit, the coil I2 is deenergized and the field structure I0 demagnetized. The armature, due to its momentum and the cessation of the force causing it to bridge the poles il, moves past said bridging position and the eccentric also moves until the cam 66 again permits the closing of the circuit through contacts 16 and 60, when the armature again receives a magnetic impulse or kick.

The pairs of contacts operate in alternation as the lever portion 5I moves first to one side and then to the other side of its mid-position, and it will be apparent that to each revolution of the armature corresponds one complete operative cycle of the lever 56 and one opening and closing of each pair of contacts 16 and 66, corresponding each to one impulse of the armature.

It will be understood that instead of connecting the two pairs of contacts 16 and 66 in series, as here shown, I may connect them in other ways and still secure the proper operation of the motor. For example, a parallel connection might be used, with the contacts 16 and 60 normally open, while the cam would serve to close them alternately and energize the coil I2 at each closing of one of said pairs of contacts.

In order to increase the effectiveness of the make and break system, I have shown a condenser |66 shunted across the contacts 16 and 66. which may be done conveniently in the construction shown, by connecting its terminals respectively to the ends of leads |66 and |62.

Since the motor will not be self-starting if it should happen that the circuit is open, I have shown starting means in the form of a starting wheel |66 carried by the armature shaft. As shown in the drawings this wheel is mounted on the end of shaft I6 opposite to that in which the eccentric is positioned and its rim is shown as knurled or corrugated and as accessible to a user through the slot |66 provided in the casina section 26. By means of his iinger the operator may, after connecting the motor to the power source push the knurled rim of wheel |66 and rotate the same until the motor starts, or he may, before connecting the motor to the power source rotate the armature into a starting position corresponding to a point at which the circuit has lust closed and the armature is in a position roughly about half-way between the poles. To indicate such a position the starting wheel may be provided with a suitable mark such for example as shown at Ill, that is, a rim portion from which the corrugations have been omitted, and a corresponding mark (not shown) may be provided on the casing, and it is only necessary to bring these marks into registration in order to assure the starting of the motor as soon as it is connected to the power source.

The wheel |06 may be connected to the shaft I6 in any suitable or preferred manner, as for example by the screw ||2 holding the end of the. shaft in a keyed recess in the wheel.

For the purpose of locking the shaving head 22 in place, I have shown a detent ||6 located in a recess in the casing section and having its nose portion III passing through an aperture in said casing section and adapted to press against the shaving head when it is suitably adjusted by means of the screw |26 by which it is attached to the casing section 22. In order to secure a more positive locking of the shaving head I may provide a groove in the wall thereof into which the nose ||6 of the detent may enter.

Protruding through openings |22 in the forward end of the casing are shown a pair of pins |26 provided at an intermediate point thereof with abutments in the form of collars indicated at |26, and each having its inner end portion passing through an aperture |28 in a bracket |62 upstanding from the member 6I (see Figure 6). Each aperture |26 is sufficiently large to permit lateral movement of the pin |26 therein, and the openings |22 in the casing also permit lateral movement of the pins' |24 therein. A coil spring |32 is shown positioned on each pin between the collar |26 and a bracket |30 and this spring presses against the collar |26 so as to urge the pin outward but without preventing its inward movement when pressure is brought to bear on the outer end lof the pin. In order to keep the pins substantially parallel to each other no matter how they move as they contact the moving parts of the shaving head', I have shown a plate |26 provided with apertures through one of which each of the pins passes, each of said apertures serving to hold the pins a fixed distance apart. and said plate is further shown as provided with a centrally positioned aperture through which the lever 66 passes, this aperture however being large enough to permit free lateral movement of the lever therewithin.

By the use of plate |66 it will be observed that the outward movement of the pins |24 is limited and as they move their positions are substantially parallel to each other at all times. -It will be observed that it is impossible to remove the pins from their seats without lifting out the plate |34 and this cannot be `done without rst removing the lever 5I from the aperture oi' the plate |34, which requires disassembly of the same from the casing.

It will of course be understood that li desired the plate |34 can be dispensed with; vin that case the openings |22 might be made oi suinciently restricted size so that the walls oi.' the reinforced portions 34 and 32 of the casing sections 20 and 22 would serve as abutments to take up the thrust of the collar |20 of the pin |24. It will be noted however that with this construction the positions of the pins would not be kept, parallel and that as soon as the casing sections 20 and 22 are separated, there would be great danger and likelihood that the pins |24 on receiving a slight displacement might suddenly ily out of their positions in the casing due to the resilient action of the springs |22.

The pins |24 are intended to enter the shaving head and to exert pressure against parts thereof for the purpose of maintaining contact between them. Since the pins can freely move laterally it will be obvious that their end portions are free to follow any movable parts of the razor head with which they '-contact, thereby eliminating sliding friction at the points of contact.

I have herein disclosed the details of construction of one speciiic embodiment oi my invention and it will be understood that this has been done only for purposes oi' illustration and that my invention may be embodied in many other forms kdiiering in construction from that herein illustrated without departing from the spirit thereof as will be obvious to those skilled in the art. The disclosure herein therefore of the details of construction of one embodiment is not to be interpreted in a limiting sense and my invention is not to be limited thereby other than as called for by the prior art.

Having thus described my invention and illustrated its use what I claim as new and desire to secure by Letters Patent is:

1. In an electromotor, a make and break device comprising two sets of paired contacts connected in series so that when 'the contacts of either set are separated the motor circuit will be broken, means for normally holding the contacts of each set in adjacency but permitting their separation and a single means for alternately separating the contacts of either set.

2. In an electric motor of the magnetic type, a make `and break device comprising two sets of paired contacts connected in series so that when the contacts of either set are separated the motor circuit will be broken, means tor normally holding the contacts oi .each set in adjacency but permitting their separation and means fo; alternately separating the contacts of either se 3. In an electric motor of the magnetic type, a make and break device comprising two sets of paired contacts connected in series so that when the contacts of either set are separated the motor circuit will be broken, one contact o! each set being ilxed,v means for urging the other contact of each set toward the iixed contact of the set, and means for alternately separating the contacts of either set.

4. In an electric motor of the magnetic type, a make and break device comprising two sets of paired contacts connected in series so that when the contacts of either set are separated the motor circuit will be broken, one contact of each set being xed, means for urging the other contact of each set toward the xed contact of the set, and means for alternately separating the contacts of either set and means ort adjusting the position of said ilxed conac s.

5. In an electric motor of the magnetic type, a make and break system comprising a plurality of pairs of contacts connected in series in the motor circuit, so that when the contacts of any one pair are separated the motor circuit will be broken, means for causing the separation of the contacts oi one of said pairs of contacts while the others remain closed and a condenser shunted across the serially connected pairs of contacts.

6. In an electric motor of the magnetic type, a make and break system comprising a plurality of pairs of contacts connected in series in the motor circuit, so that when the contacts of any one pair are separated the motor circuit will be broken, means for causing the separation of the contacts and a condenser shunted across the serially connected pairs of contacts.

7. In a motor operated tool operated by an electric motor of the magnetic type, a make and break device for said motor, having a plurality of sets of contacts arranged in series in the motor circuit, so that when the contacts of any one pair are separated the motor circuit will be broken, an oscillating lever for transmitting motion from said motor to said tool, and means on said lever associated with the contacts oi each set for causing separation of the contacts thereof.

8. Means for assuring the starting of an electric motor of the magnetic type comprising indicia positioned in xed relation respectively with the rotor and the stator of the motor, and their relative positions being such that when said respective indicia are brought into registration with each other the motor will be in a starting position and will start as soon as the electric current is turned on.

GODFREY DALKOWITZ.

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