US1109689A - Electric-circuit closer and breaker. - Google Patents

Description

T; E. MoQUOWN. ELECTRIC CIRCUIT CLOSER. AND BREAKER AIPLIGATION FILED NIOV; 24, 1906.

1,109,689 hten'ted Sept. 8, 1914.

nu/f if I) UTE STATES PATENT @FFFLCE.

THOMAS H. MOQUOWN, OF CAMBRIDGE. MASSACHUSETTS, ASSIGNOR. BY DIRECT AND MESNE ASSIGNMENTS, SYLVANIA.

'10 ARTHUR AT'WATER KENT, OF PHILADELPHIA, PENN- ELECTRIC-CIRCUIT CLOSER AND BREAKER.

specification of Letters Patent.

llatented Sept. 8, 1914-.

To all ill/1,0777, it may concern Be it known that l, Tnoams H. MoQUowN, a citizen of the United States, and resident of Cambridge, county of lvliddlesex, State of ll iassachusetts, have invented an improvement in Electric-Circuit Closers and Breakers, of which the following description. in connection with the accompanying drawing, is a specification, like letters on the drawing representing like parts.

This invention relates to a device formaking and breaki g an electric circuit. Dcvices of this character are commonly used in quite a variety of mechanism, such for instance as electric time recorders, electric speed recorders, ignition devices for internal combustion engines, etc.

In most of these mechanisms it is necessary to close the circuit momentarily only, the mere closing and breaking of the circuit serving to operate the mechanism with which the make-and-break device is used, and in order to prevent any unnecessary consumption of current it is desirable that as soon as the circuit has been closed it should be instantly opened again.

A device which is adapted to break the circuit instantly that it is closed is shown in my prior Reissued Patent No. 12,273, reissued October 11, 1904.

In order to get the best result from these makc-and-brcak devices it is also desirable that during the short interval of time that the contacts are closed together there should be a good electrical contact between the contacts, and also that when they are separated to break the circuit the separation should be instantaneous.

The necessary good electric contact can usually be produced by bringing the contacts together with some little ressure, but 1n order to get the best sparking effect where the circuit is broken it is desirable to separate the contacts instantly while they are still under pressurerather than to separate them in such a way that'the pressurebetween them will gradually diminish to zero andthereafter the contacts begin to open :1 art. p

.make-and-break device in which the contacts "are not only broken instantly that the circuit In my present invention I have provided a is closed, but one in which the separation of the contacts occurs instantaneously from a closed condition in which they are pressed together with some force. This result is preferably secured by so constructing one of the contacts that it constantly acted upon by some force which tends to move it to\ aid the other contact, so that when the latter contact is moved against the first contact to close the circuit the contacts are held together bythis force. and when the contacts separate to break the circuit the separation occurs instantancmisly at a time when they are thus pressed together. One convenient way of accoimilishing this result is to cmploy a spring of equivalent device which constantly acts on one contact to move it toward the other, the movement of said first contact toward the other being limited by a suitable stop. lVhcn said other contact is closed against the first contact to close the circuit the two contacts are pressed together by action of the spring. thus making the necessary good electrical contact, and when the latter contact moves away from the for mer the breaking or separation occurs while they are thus pressed together thus producing the desirable instantaneous break.

My invention may be embodied in various devices. and in order to illustrate it I have shown it as embodied in a make-and-br*ak device for a ships log. The invention however is not limited to use in connection with such an aiparatus as will be obvious.

in the rawings l igure 1 is a perspective view showing a ships log embodying my invention; Fig. 2 is a View of the casing for the a )paratus with the cover removed showing the make and break device; Fig. 3 is a detail of the contact-closing member; Fig.

4 is a detail of the make-and-break device;

Fig. 5 shows another modification of the invention; Fig. (3 is a section through the post or stud 5.

Referring first to Figs. 2, 3 and d, the two contacts of the make-and-break device are designated by 3 and l, andin order to avoid confusion I will refer to the contact 3 as the fixed contact and to contact 4 as the movable contact. It will be understood however that the fixed contact 3 is not necessarily an absolutely rigid and unyielding contact but only one that is fixed relative to the contact 4 which moves toward and from the contact l 3. The fixed contact 3 is shown as an arm is acted upon by means suclr'for instance as spring 6 which normally tends to force it toward the movable contact.

In the embodiment of the invention herein illustrated the spring 6 has one end coiled around and secured to the stud 5 and the other end bent to engage the upper side of the contact 3. With this arrangement the spring will tend to swingthc contact 3 downwardly toward the contact 4.; its movement in this direction is limited by a suitable stop 8 which may be in the form of a. pin projecting 'lron'rthe backing piece 9 on which the contact is mounted.

The movable contact t is shown as pivoted on a stud 10 which also extends from the backing piece 9, and preferably it will be acted upon by a suitable spring 11 tending to move it away from the contact 12- is a stop which serves to limit the downward movement of the contact at. lVith this construction it will be seen that the sprlngo acts to hold the contact 3 against the stop 8 with more or less pressure depending upon the resiliency of the spring 6.

If the movable contact i is moved upwardly sutliciently to engage the fixed contact 3 and lift it from the stop 8 the contacts will.be held together by the pressure due to the action of the spring 6, which is suiiicient to furnish a good electrical contact between said contacts. This pressure will be maintained While said contacts are closed together.

When the movable contact 4: swings downwardly the fixed contact 3 will follow it, said contacts still beingpressed together by the action of the spring 6 until the contact 3 rests against the stop 8 when the pressure with which the contacts are held together is instantly removed and the separation of the contacts occurs instantaneously and while they are still under pressure. I

The means herein shown for giving move ment to the movable contact 4 is of such a construction that the two contacts will be broken instantly that they are closed. The movable contact 4 is given its closing movement by means of a contact-closing member 12, herein shown as a cam loosely mounted upon a stud or pivot 13. This contact-closing member is turned about its stud thereby to bring the cam portion thereof against the movable contact 4 to force the latter against the fixed contact 3, and suitable means are employed to accelerate the movement of the contact-closing member at the time that it is about to engage, with the movable. contact so as to cause the contacts to be quickly closed and then instantly opened.

The means herein shown for-actuating the contact-closing member oomprisesa gear wheel 1 1: formed with a shoulder 15 which is adapted to engage a. pin 16 which extends loosely through a slot 18 in the contact-clos ing member, and is carried by an an; 17 loosely carried by the stud 13.

{llhearm 17 is acted upon by a suitable spring, .weight or other automatically operating means which tends to huh. it in the position shown in Fig. I have herein shown for this purpose a weight 19 which is pivoted to the casing 20, as at 21, and which is link 22.

The operation of the parts thus tar do" scribed will be apparent to those skilled in the art and is as follows: As the gear 14% rotates in. the direction oi the arrow (1., Fig. 3, the shoulder 15 engages the end of the pin 16 and carries s'aid pin and the arm 17 around with it and as said pin. reaches the end of the slot 18 the cauitact-closing menr ber 12 is also carried around with the gear. When the arm 17 has been carried around slightly past its vertical position, as shown in Fig. 4, the action of the weight 19 will tend to accelerate the movement oi the arm 17 and carry it quickly into the position shown in Fig. 2, and because the pin 16 extends through the slot in the member 12 the movement of the contact-closing member 12 is accelerated. The acceleration oi the contact-closing member occurs ust prior to the time that it engages the movable contact 4-, and the result is that the accelerated movement of the contact-closing member 1'). carries said member out from engag ment with the movable contact l almost iils'itantly that, it is brought into engagement therewith. The contacts are thus vermitted to separate almost instantly that they are cl sed. During the accelerated movement oi the arm 17 the pin 16 thereof is carried ahead of the shoulder 15 as will be obvious, and said pin shown in Fi 2, remain in sue position until during to rotation of the gear 14 the shoulder 15 has again come in contact with the pin.

capable of operating when the gear 14 turns in either direction, andaccordmgly I have shown the gear 14 as having two opposed shoulders, one the shoulder 15 above described and the otherthe shoulder 25. One shoulder is operative when the gear is moving'in one direction and the other is opertive when the gear is movin in the opposite direction. The contact-closing member 12 is also made symmetrical in shape so that it may operate in either direction. It de sired the movable contact 1 may carry a friction roll 26 with which the contact-(low ing member engages thereby to reduce the friction between the parts. In the present embodiment of my invention this makeandbreak device is shown as used in conjunction with a ships log, and it accordingly is so mounted that the gear 11 may he turned connected to the pin 16 by means of a and arm 17 will, after reachin Y the position- It is desirable to make the mechanism by a usual rotator which drags through the water and operates the log.

The operative parts are inclosed in a suitable casing 20 which is shown as having a hollow stem 27 extending therefrom through which extends and in which is journaled a shaft 28 to which the line 29 leading to the rotator is connected. This shaft 28 has fast thereon a pinion 30 which meshes with and drives the gear 14. The casing 20 is supported by a universal joint device that it may swing both a vertical and horizontal axis to permit it to accommodate itself to the motion of the vessel. It is shown as pivoted to the arms 31 of a yoke device which in turn is pivoted to turn about a vertical stud 32 carried by a bracket 33. This bracket may be secured to any suitable portion of the vessel, as for instance to the tafl rail 34. I have shown the stand 33 as detachably secured to the taii'rails 34, it be ing removably supported by a base piece 35 which is screwed to said tafi'rail.

'gThe complete device herein shown is gwadapted to be used in connection with some electrical recording device, such for instance as shown in my Patent No. 749,743, dated January 19, 1904, with which device the contacts of the mechanism herein shown will be electrically connected.

It will be obvious of course that the contacts 3 and 4 must be insulated from each other when they: are separated, and to accomplish this both aremounted upon a block 9 of insulating material, and the studs 5 and 10 on which said contacts are mounted may extend through the insulating material and through the back of the case and constitute binding posts 36 to which the wires of the circuit may be connected.

I have also shown a registering device mechanically connected with the rotary shaft 28 so that the rotations of the shaft m'ay be read directly from the casing 20 if desired. For this purpose the hub of the gear lt has thereon a worm 37 which meshes with and drives a worm gear on a vertical,

shaft 38. Said shaft 38 has at its upper end another worm which meshes with and drives a worm gear 39 on the shaft 40 of any suitable registering device 41. The casing 20 is provided :with a removable cover 42 which preferably has the sight opening 43 through which the registering device 41 may be read.

In Fig.5? 5 I have shown another form of my invention in which the fixed contact is made resilient, and the resiliency thereof is the force which tends to move said contact toward the movable contact; In this embodiment of my invention the fixed contact 300 is a resilent member which is rigidly secured to its supporting member as at 301.

Said fixed contacts normally rest against a stop 800 which is so situated that said movable contact when resting. thereagainst is under tension, the resiliency of "the fixed contact holding it against the stop with more or less pressure. The movable contact 400 may be moved against the fixed contact by any suitable means. It will be noted that in this form of the invention when the movable contact during its movement engages the fixed contact 300 and lifts the same from its stop 800 the resiliency of said fixed contact 300 holds the contacts together with sufficient force to produce the necessary good electrical contact between them, and that as soon as the movable contact moves downwardly this pressure is maintained until the fixed contact rests on the step 800 when the contacts instantly separate thus breaking the circuit while the contact 300 is still under tension.

Having described my invention what I claim as new and desire to secure by Letters Patent is 1. in a make and break device the combination of a shaft, a wheel mounted on said shaft and rigidly secured thereto andcarrying a pair of oppositely arranged shouiders,

ders, a contact point, a movable support therefor, a symmetrical contact closing member having an arc-shaped projection to operatively engage said support, said contact closing member being loosely mounted on said shaft between said arm'and said wheel and provided with a slot through which said pin extends; a stationary contact point arranged to cooperate with said mentioned contact point, and yielding means also connected to said pin and acting on said arm immediateily prior to the instant that said arc-shaped projection passes through a plane passing through the point of the operative engagement of said su port with said projection and the axis of said shaft, to accelerate the movement of said contact closing member.

2. In a contact device a shift, a crank arm loose on said shaft, a. crank pin extending parallel to said shaft, a cam loosely mounted on said shaft, the peripheral surface of which that is most remote from the axis of said shaft being arc-shaped and extending concentrically to the axis of said shaft, said cam being also provided with an arc-shaped slot also concentric to the axis of said shaft andsymmetricaliy arranged with respect to and on the same side of the axis of said shaft as said arc-shaped surface or" said cam; a member rigidly secured to said shaft and having a pair of shoulders, one on each side of said shaft, said crank pin extending from said arm through said arc-shaped slot and into the path of and between said shoulders a contact point carrying arm in the path of the projecting arc-shaped surface of said cam and moved away from the axis of said shaft when operated upon by said cam, a spring tending to force said arm' toward the axis of said shaft to move said arm into its position nearest the axis of said shaft when said arm is not being acted upon by said cam, a Contact point mounted. on said contact carrying arm, a fixed contact point coiiperating therewith, and a Weight connected to said crank pin and normally holding said crank pin in aiinement With the 1,1oa,ese

axis of said shaft and the pointoi: engzwemeat of said cam wiihsaid incvahie 00 i, support and on that side of the axis of ca' shaft diametrically opposite to that 01': support.

In testimony whereof, I have signed my name to this specificatik'uu in {he presence oi: two subscribing witnesses,

THOMAS H. MCQUUWR.

Witnesses LOUIS C. SMITH, MARGARET A. DUNN.

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