US2562734A - Series flux vibrator for use on synchronous clock motors - Google Patents

Description

July 31, 1951 E A. PHANEUF 2,562,734

SERIES FLUX VIBRATOR FOR USE ON SYNCHRONOUS CLOCK MOTORS Filed Feb. 26, 1948 j 48 Inventor-v: Edgar A. PhaneuF,

His Attorney.

Patented July 31, 1 951 SERIES FLUXWIBRATOR' FOR USE ON SYNCHRONOU S CLOCK MOTORS Ed'garA'. Phaneui, S'outhborough, ,Mass., assignor to Telechron,Inc.', a corporation of Maine ApplicationzFebruary 26, 1948, Serial No; 10,993

4 Claims.

My invention relatesto alternating current mos tor vibrators-such as areemployed onsynchroefor example, are described. in United'States Pat-- ent-LNo. 2,002,433..to.Cow1es,-'.May 21, 1935. The vibrator of-tmy; invention is'in series with the entire motorfluxicircuit ofithemotor and is readily adapted for application to. various typesof motors, including.the=conoentric core type" such as isdescribedinUnited States Patent No. 1,977,186 to Haydon, October 16,.1934,:aswe1l aszto motor structures such as aredescribed in -the abovementionedCowles patent. Moreover, instead. of shunting flux away'fromthe motor air gap and therefore decreasing; the: iiux available for. motor torque I have-found that' my. magnetic vibrator whichis .in series with :the motor flux. and rotor air. gap. distinctly'improves: the motor. torque of reluctance typeamotors when the vibrator is in operation.

The featuresof my. invention whichare-believed'to beinovel and patentablewill be pointed outtintheclaimsappendedhereto. For a better understanding of my invention, reference is madein-tthe following description to the accompanyingdraw-ing in which Fig. 1 shows in part airont elevation andFig. 2-in part a bottomview of an alternating current clock motor structure to which my invention hasbeen applied, by providing an air gap in the stator magnetic circuit atone end ofthecoreand resiliently mounting thecoreso thatthis gap will open and close with the flux pulsations; Fig. 2 also shows cam means for holdingthe-gap closed'when avibratory alarm noise is undesired, and time control release means for causingthe.vibratory. alarm to sound ata selected time. Fig. 3 shows in part arear elevation andFig. 4 a plan View of. a-concentric core type of alternating current -clock:motor and the application of my invention theretofor alarm clock purposes; and Fig.,- 5'shows in part an end elevation. and Fig. 6 in part a bottom view of an alternating-current motor of the multipolar ofiset core type :representing. the application of. my inven-- tion thereto. I

In Figs, lv and,.2-there isrepresented a twopole; shaded -polesynchronous motor of the type described in United States-Patent No. 1,168,386

toiWarren,Junei24, 1930, .to which my, invention of corev I.

has beenapplied Theistator comprises the lame inated magnetic. core I about which the single phase exciting coil.2is woundand the two laminated polepiece limbs 3 and 4. Adjacent the rotor'air gap, these limbs are split into two halves and have shading coil 5fon each trailing pole half. A polar rotor 6 of'the hysteresis type is mounted. forrotation within the rotor air gap and is schematically represented for driving an alarm clock. gear train I having an alarm cam 8 which willbe driven at one revolution in twelve or twenty-four hoursand' is adjustable relative tothe clock hands for setting the time for the alarm to sound. As represented in Fig. 2, the cam amaybeconnected to its driving gear'by a friction clutch 9,802,511) be adjusted with respect to such gear bythe thumb'piece III on the shaft of cam 8.

As. shown inFig. 2', I'have provided an adjustableairgap, IIJ'between the limb 4 and core I of themotor. stator in series with the flux cir cuit of the motor. The stator structure'is supportedv by posts 23'at itsrotor end; and the core I is sufiiciently. resiliently mounted so 'thatzit may vibrate between tthe open gap position represented in Fig. 2' to a position in contact with limb 4. The .normal' position when unrestrained and withthemotorv unexcitedi is that shown. Whenthe motor. is excited with commercial frequency alternatingcurrent, the flux crosses this gapand magnetic attraction causes the'parts to be drawn together and the gap closed synchronously withthe flux pulsations, and to open again as the flux passes through zero values. Thus the magnetic parts which face each-other across this gap vibrate and cause a vibrating noise as they striketogether. The resiliency of'the mounting must besuch' as .to permit this if the vibratory alarmnoise is to be obtained, and the loudness of. this ,noise depends somewhat upon the maximum. air. gap. which occurs at It] and the resiliency of the mounting. As represented in Fig. 2, the-.end'of core I adjacent gap I0 is supported by aflnonmagnetic spring. arm I I secured to limb 4lby.-a bolt or rivet I2; The other end of core I is preferably fastened rigidly to the otherwise free .endlofilimb-3I When so mounted, the core vibrates'suificiently for the-intended purpose. I have tried mounting both ends of the core resiliently as, described for the one end. While this increases the vibratory'noise, it is unnecessary as the one gap. is suflicient for this purpose.

In Fig, Zthere is shown a cam It the periphery of which forms a back stop for the vibratory end The position of this cam represented in Fig. 2 allows a maximum air gap at IU. Rotating the cam I3, 180 degrees from the position shown, closes the gap l and prevents the vibration described even though the motor be energized. Hence, the rotary position of this cam and its shape determine the absence or presence of the vibratory alarm and its loudness when vibration is permitted, and serve as a device for turning on and off the alarm when the motordriven clock is in operation.

It is now a simple matter to associate this cam with the usual alarm letolf device found on alarm clocks, so as to cause the vibratory alarm to sound at a predetermined set time, and also to shut the alarm off manually when the sleeper has been awakened. One way of doing this is somewhat schematically illustrated in Fig. 2. Associated with the periphery of the alarm cam 8 is a cam follower lever [A pivoted at l and biased by gravity, or otherwise, to rest against the cam 8. This lever has two offset latches l6 and l! thereon. The shaft of cam [3 has athumb-piece is for turning it manually. It also has a latch arm l9 having an offset latch projection at 26. In the alarm on position of cam I3 shown, the arm [9 rests against a stop 2| and is biased counterclockwise against this stop by a spring 22. To shut the alarm off, cam l3 and arm [9 are rotated about 180 degrees more or less clockwise manuallywhere the latch projection on the arm cooperates with either latch 16 or IT. These latches are beveled so that when arm 20 is turned manually to the off position, the latch projection will pass by behind whichever latch H5 or i? it engages and, in so doing, the cam lever will be momentarily moved to' the left, lifting its cam follower off cam 8 and dropping back'again as soon as the engaging latch has been passed by. The latches I6 and ll are slightly staggered so thatif the cam follower end of lever I4 is in the depression of the alarm cam 8, latch 20 will engage with latch I1; and when the arm l9 has been turned clockwise slightly beyond the position of latch I! and released, the latch I! will hold arm IS in this alarm off position.

If, on the other hand, lever I4 rests on the high part of cam 8 when the alarm is turned off, latch finger 20 will contact latch finger l6 and will not contact latch ffinger i! even though turned that far. When released, arm 20 will be held by latch ll in alarm off position. When the lever l4 again drops into the depression in alarm cam 8, arm 20 will be released and spring 22 will move it to the alarm position shown and the alarm will sound. In case the alarm is turned off very'soon after it sounds automatically and arm I9 is retained by latch ll as above described, when the lever I4 is shifted to the left by the'rise in the cam 8, lever 19 will be released by latch ll but will then be caught by latch 16. Hence, this double staggered latch arrangement is advan tageous in that the alarm may be turned off immediately and will reset itself automatically for the next scheduled automatic alarm operation without further attention. In the usual alarm clock, if the alarm is turned off immediately after it sounds, it must be reset for automatic operation some time later. Otherwise, it will not operate at the next scheduled alarm period.

It is to be noted that except for the relatively short proportion of the time when the alarm is in vibratory operation, assuming normalconditions, the gap i0 is closed and the motor magnetic circuit has a reluctance corresponding to that of a normal motor and hence has starting and operating characteristics corresponding to a normal motor. No flux is shunted from the rotor flux path. When the alarm is in operation, it can produce the maximum noise energy possible for a given watt input to the motor. The running characteristics of the hysteresis type of motor described do not appear to be affected when the vibrator is in operation, and the starting characteristics of this type of motor appear to be only slightly impaired.

Figs. 3 and 4 represent the application of the invention to the concentric coil type of synchronous reluctance motor, or a motor of the type described in United States Patent No. 1,977,186. In this type of motor a central magnetic core 24 is surrounded by an energizing coil 25. To one .end of the core is fastened a polar magnetic plate 26, and closely adjacent thereto and concentric with the core is a polar magnetic rotor 21. The magnetic circuit from the other end of the core is completed by a magnetic cup 28, which in the usual motor of this type has its inner bottom centered against the end of the core opposite or otherwise magnetically connected thereto. The side walls of the cup 28 extend adjacent the rotor periphery and in some cases may have polar teeth out therein opposite the rotor.

I have modified this construction by providing an opening in the bottom of the cup 28 so that it is spaced from the core by a nonmagnetic spacer washer 29 such that there is the equivalent of a concentric air gap at this point. Then I provide a washer-shaped magnetic part 30 resiliently mounted adjacent the magnetic gap at 25 and large enough to bridge the concentric gap between the core and magnetic part 28. The resilient mounting of part 30 is such that it is normally spaced slightly away from thecore 24 as shown but such as to be magnetically attracted to strike against the adjacent magnetic parts in synchronism with the alternating flux pulsations in the magnetic circuit of the motor to produce a vibratory alarm when the motor is energized with alternating current. In the example shown this resilient mounting comprises a nonmagnetic resilient strap 3| secured between the side wall of the cup 28 and the magnetic armature member 30 of the vibrator. It is thus-seen that the vibrator is operated by the series flux of the motor.

In order to prevent this vibrator alarm from operating, the armature 30 may be held from vibration either in the position shown or up against theend surfaces of core 25 and cup 28,

, and for this purpose I have shown a bail type of sprin wire clamp such as is commonly used on fruit jars to hold the armature up against the core. This clam-p consists of wire having a clamping part 32'diametri-cally embracing the -central part of the armature 30 and-retained in such central position by a slotted guide part 33 fixed to the armature, and abail-lilre operating lever part 34 for moving the part-32between-clamping and unclamping positions. T-he lever part 34 is pivoted to opposite sides of the motor-shell 28 and securedto-clarnping part 32 on a line suffic'iently offset from the pivot axis so as to obtain a lever action on the part 32 to move it between armature clamping and unclamping positions. The parts as shown in Fig. 4 are in the unclamped position. Armature 30 is biased to the detracted position by spring SI and is free to vibrate. The slot in guide 33 permits such vibration without interference from clampingwire member 32. When th'elever part 34 is pulled down to the aceegvee dotted line positionindicated34a, the clamping part 32 is pulled down securely to clamp' the armature 38- against the end of the motor housing in nonvibrating flux gap closing position.

When the part 34 is thus moved from full line position to position 34a, there is a resilient'tensioning of the wire parts so that, if released, it will spring baci: to full line position. If the part 34' be moved still further to the'position indi-' cated by dotted lines at 34b, it will beretained in this position by reaso'n'of a toggle action of the wire parts. In this 34bpositionthearmature isalso clamped in nonvibratingfiuxgap closing-- position.

In Fig. 4, I have indicated a gear reduction train 35 by means..of.which.the motor shaft 36 may drive hour and minute clockhands 31 and 38; Geared-to the hour hand 'shaft igan alarm cam member 39. A friction clutchi idintervenes.

to enable-the; cam to'be set byan alarm setting shaft 45: I have shownan alarm release leverflfpivoted at 43 andarranged toi'be"re= leased by the cam pin 39 as'such pin iszrotated past one position in its path of rotation. Lever'42 is provided with. aslatch ati.44',..movable into and out of a position to hold. or..release wire lever. 34 when inthe alarm set position 34a. The lver 42 may be biased to such holding position against a stop as by a spring 45. It is now evident that if lever 34 be in position 34a and retained there by the release lever 42, and the clock is in operation, a time will arrive when pin 39 moving down and to the right as seen in Fig. 4 will engage the free end of lever 42 and move it to the right and thus release the alarm at a time determined by the alarm setting. The serie motor flux vibrator armature 30 will then sound a vibratory alarm until shut off by moving lever 34 to position 34a or 34b. The alarm may be permanently shut off immediately after it starts to operate by moving the lever 34 to position 34b. Later when the release lever 42 has moved back to holding position, lever 34 may be moved manually from position 341) to 34a to set the alarm for the next scheduled alarm period.

I have found that with respect to the reluctance type of synchronous motor here briefly described, the starting and operating characteristics are actually substantially improved when the vibrator alarm is in operation. Apparently the synchronous opening and closing of the flux gap by the vibrating armature 30 has a beneficial effect in controlling the size or shape of the flux pulsations which act upon the polar motor rotor 21. When the armature of the vibrator i held in nonvibrating, gap closing position, the motor operation characteristics are those of the normal motor of this type. The series flux vibrator alarm is especially beneficial for use with motors of the type shown in Figs. 3, 4, because with these types of motors it is not practicable to use a shunt flux vibrator.

In Figs. 5 and 6 my invention is shown as applied to the offset type of multipolar single phase synchronous motor. In this type of motor there is a magnetic core 46 surrounded by a single phase coil 47. From opposite ends of the core magnetic stator plates 4 and 49 extend at right angle to the core in one direction. The extremities of these plates each have a circular series of teeth or pole pieces 59 offset toward each other and interleaved so as to form a partial circle of uniformly spaced teeth of opposite polarity. This general type of motor is described in my patent No. 2,541,830, February 13, 1951. Within this 6 partial circle is a polar rotor.52 rotatively sup. ported on an axis of rotation at 5!. Supporting studs 53 of the pillar type space and secure the:

clearance so that these parts do not contact each other. Also, the plate 49 is normally spaced slightly from the adjacent end of the larger'section of the core so as to leave an air gap" at 56. The stator-plate 48 at the opposite end is rigidly securedto the core and to stationary supporting structure designated at 51, and the plate 49 which forms the vibrator armature of the alarm is secured 'toplate 48 by the studs 53. Thus the lower endof "plate 49 as represented in Fig. 5'is'unsupportedandthere is suziicient resiliencyin this plateand inits supporting structure to allow the lowerend to" vibrate as a magnetic armature when the motor isenergized by single phase al=- ter'nating current and, in so doing, to move to and from th'e'positio'n represented-in Fig. 6 and strike against the end of large core part 46.

This series flux vibrator arrangement in no way interferes with the'operation of the motor and, intact, improves-its starting operating characteristics when the armature is allowed to vibrate and at the same time is operating as a sound vibrator. When the vibrator sound is not desired, I provide a shutoff device consisting of a cam lever 56 pivoted at 51 to the reduced core extension 55. The position of this cam lever represented in Fig. 6 allows the armature plate 49 to vibrate, and the loudness of the sound produced may be controlled by an adjustable back stop 58 for such lever. The lever is biased against the stop 58 by a spring 59.

When the vibrator alarm is to be shut oli, lever 58 is pulled over to the right and retained by a catch Gil and a pin 3!. This presses the armature plate 49 against the end of large core part 43 and closes the gap 56. The latch {56 may be released manually or in response to an alarm clock. release mechanism as previously explained and when re leased, allows the cam lever 55 to be pulled over to the alarm on position represented, by spring 59.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. In combination, a single phase alternating current motor having a magnetic circuit energized by a single phase winding, a rotor for said motor and a magnetic vibrator in series in the flux path of said magnetic circuit, said magnetic vibrator comprising relatively movable magnetic parts resiliently biased in spaced relation to provide a magnetic gap in series in the flux path of the motor, which parts are adapted to be alternately magnetically attracted together and separated by the resilient bias in vibratory synchronous relation with the flux pulsations of said motor, and means movable between releasing and holding positions for holding the parts of said vibrator together when said means is in holding position.

2. In combination, a single phase alternating current motor having a magnetic circuit energized by a single phase winding, a rotor for said motor and a magnetic vibrator in series in the flux path of said magnetic circuit, said magnetic vibrator comprising relatively movable magnetic parts resiliently biased in spaced relation to provide a magnetic gap in the series flux path of the motor, which parts are adapted to be alternately magnetically attracted together and separated by the resilient bias in vibratory synchronous relation with the flux pulsations of said motor, and means movable between releasing and holding positions for holding the parts of said vibrator against vibration when said means is in holding position.

3. In combination, a single phase alternating current motor comprising a magnetic circuit, a single phase winding for energizing said magnetic circuit, a rotor forsaid motor and a magnetic vibrator in series at different points in said magnetic circuit, said magnetic vibrator comprising relatively movable magnetic parts, one of which is resiliently biased in spaced relation to the other part to provide a magnetic gap in series in the'flux path of said motor, which parts are adapted to be alternately magnetically attracted together and separated by the resilient bias in vibratory synchronous relation with the flux pulsations of said motor, control means movable between releasing and holding positions for holding said parts against vibration when said con trol means is in holding position, means for biasing said control means toward the releasing positionjand means for releasably holding said'control means in holding position.

4. In combination, a single phase alternating current synchronous motor, said motor having a magnetic circuit, a single phase coil for energizing said circuit, and a motor rotor and a magnetic vibrator in series in the flux path of said magnetic circuit, a control means associated with said magnetic vibrator movable between holding and releasing positions for holding said magnetic vibrator against vibration when said control means is in holding position, means for biasing said control means toward releasing position, a releasable catch for holding said control means in holding position, and means responsive to the operation of said motor for releasing said catch at a predetermined time.

EDGAR A. PHANEUF.

REFERENCES CITED The following references are of record in the file of this patent:

UN STATES PATENTS

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