US1176634A - Time element. - Google Patents

Description

A. AICHLLE.

UME ELEMENT.

APPLICATIBR FILED IAV l2, 19H 1.176,634. Patenxted Mar. 21, 191s.

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ALBERT AICHELE, F BADEN, SWITZERLAND, ASSIGNOB TO AKTIENGESELLSCHAFT BROWN BOVERI & CIE., OF BADEN, SWITZERLAND.

TIME ELEMENT.

Specification of Letters Patent.

Patented Mar. 21, 1916.

' To au whom it may concern.'

Be it knownl that I, ALBERT AICHELE, a citizen of the Swiss Republic, and residing at Baden, Switzerland, have invented certain new and useful Improvements in and Relating to Time Elements, of which the following is a specification.

This invention relates to time element mechanism for overload contacts and the like.

Time elements have already been proposed in which the clockwork is driven by anA electric motor. In these the rotor of the clockwork motor is arranged in the iron circuit of the relay magnet itself, so that the relay magnet supplies the field in which the rotor rotates. The clockwork after the expiration of a certain adjustable time limit unlocks the locking means for the lever effecting the cutting out of the excessive current, whereby also current is cut ofl' from the magnet winding of the time element and the relay reassumes its initial position.

The object of thel present invention is to provide an improved construction of this kind.

'lhe invention consists in a time element mechanism driven by an electric motor or otherwise the rotor being arranged in the iron circuitof an electro-magnet with movable armature, the arrangement being such that on the maximum permissible current being exceeded one end of the armature is first Vattracted whereby the driving mechanism of vthe clockwork is geared up, the other end of the armature remaining locked until the clockwork has run down. this end ot the aI- mature only being attracted after the release ol the locking means to cause, for exam le, the opening of the main switch. L y

The invention also consists in an arrangement of this kind with means whereby -a short-circuit or other heavy overload causes both ends of the armature to be attracted.

In the accompanying diagrammatic drawingsz-I `igure 1 shows the position of the parts when a normal current is fiwing; Fig. 2 shows their position just after a current above the maximum permitted has begun to flow; F ig. 3 shows the position which the parts take .for instance after the aforesaid excess current has flowed for a predetermined time. f

Some of the inductors illustrated in Fig.

'1 are omitted'from Figs. 2 and 3. The

shafts which are shown with section lines .are intended to be fixed in space.

In Fig. 1 the electro-magnet a is provided with a winding b through which the current flows and a limb r containing the rotor c of an electromotor operated on'the shaded ole l principle. This motor drives the gear w eel 1 which by means of the pinion 2 drives the wheel n mounted on the spindle d. On this spindle is also mounted the pinion 3 and pivoted'the'arm e connected to the main swltch or the like by a rod 3. To the arm e is pivoted at the point h an armature f; this at one end is formed with a curved pole piece' g and at the other end k has a wheel l pivoted to it and also connected to it by means of the springs s and the screw t. The armaturef also carries a flat spring 4 bearing on the rotor c and a connection for a spring z', the tension-of which can be varied by apparatus 5. The plate l has a projection m of sufficient length to engage a locking bar'o with a notch in which a projection 7 on the bar e normally engages. The plate l is provided with a slot u so that it can move on the spindle 'n and is controlled by the spring p which can be tensioned by apparatus 8.

In operation the springs ,p and s are first suitably tensioned until the various indicators show the ordinary maximum permissible current, the short-circuit current and the time element being allowed. `With excessive current the magnet a attracts the end k of the armature f, thus overcoming the actidn of the spring z', so that the said end turns about l1. By ythis means the teeth provided on the disk Z are in the first place caused to engage with the gear wheel m of the motor c and further the plate spring 4, which up to that mcfnent prevented the rotor c from rotation is lifted out of contact with the said rotor. This position of the 'apparatus is 'shown in Fig. 2. The rotor c now at once starts to r0- tate and to drive the disk Z in the direction indicated by the arrow against the action o the spring s. After a few seconds the projection m then strikes against the locking lever o, thus forcing the same in an upward direction, so that it is unlocken :t fl. The mag net a now immediately attracts the other end g of the armature f causing the release lever e to share in its movement and to open the main switch or the like (not shown). The parte now assume 'the position shown in Fig.

but only for a moment.

Immediately7 after the attraction of the armature, the coupling between the disk Z and the train of wheels n is disconnected as shown in Fig. 3, so that. the disk l is rapidly turned hy the spring into its initial position (Fig. l), that is to say, until the pin t comes into contact with the armature f. The armature f aiso only remains for a short moi ent in the closed position as on release of the main switch, the winding b is rendered currentless and the relay magnet releases its armature, so that it returns in lthe position shawn in Fig. 1.

Un short-circuiting the time element is cut out because in consequence of the increased trctive effort of the relay magnet a, the armature, ,i may be attracted at both ends k endg;y without unlocking (j, the necessary m0- tion of the lol ng bar o being permitted by the slot u.

if now in consequence of a short-circuiting the tractire. ctort of the magnet has increased to such an extent that it overcomes ,he force of the spring p then the projection g on the lever f pushes back the lockinglever o, causing o to slide in the slot u and the re lease is effected instantaneously.

The current intensity for the time release y oe adjusted bv vthe tension of the spring d 5i e current intensity for the short-cir rase bv 'the tension of the spring p.

Tige. time interval iietween responding and release may be regulated by shifting the pin t' on the disk i.

As the speed of the motor c depends upon the periodicity and not upon the current intensity in the winding 1, the time between tlfzc responding and release of the relay is aiso independent of the releasing current. A clockwork motor, however, might be used, the speed of which would be dependent in some vmanner upon the releasing current. 'ihc releasing period would then be dependent upon the releasing current.

Arrangements as described above have the advantage that the armature does not stick but is immediately released when the exciting euri-mit e *he relay falls to its permissille value even "ore thc running down of the ciockwork, 'Inc reason ot' this is the iron circuit of' thc relay magnet comprises 'two air gaps, so that when the magnet has attr 4ted ne rofl ci thi: arnfatm n there .still us an air ule'ch as is wel known.

reni j; ts an cxressiw increase of' tlnfield,

Ionserpicntly :i "srickirg" of the armature. This effect is further increased by the circumstance that the path `which must' be traversed by the armature in order to couple the clockwork to its driving member, and conseipn-ntly the distance separating the respective end of the armature from the relay magnet'nced only be very small, whereas mostly a shorter path must be traversed by the armature for the purpose of effecting a release. The air gap which is bridged in the first place owing to the one-sided attraction of the armature on the occurrence of an eX- cessive current,amounts therefore only to a small fraction of the total air gap atboth ends of the armature.

Having now described my invention what I claim as new and desire to secure by Letters Patent is:-

1. Time element mechanism comprising an electro-magnet, a lever with a projection thereon, an electro-magnet armature pivoted on the lever, a toothed disk carried on said armature, gearing adapted to drive Said toothed disk and a motor arranged to drive said gearing, a locking leverV with a notch engaging the projection on the first mentioned lever and springs controlling the action respectively of the electro-magnet armature, the toothed disk andthe locking lever.

2. Time element mechanism comprising an electromagnct, a rotor disposed in a gap in said magnet and adapted to be driven thereby, a train of gearing in connection with said rotor, a pivoted lever with a projection,

an armature for said electro-magnet pivoted on said lever, a toothed disk `rhavlng a projection and also a slot, said disk being mounted on said electro-magnet armature, a blade spring connected with said armature and adapted to press on said rotor, a locking lever having a notch to engage the projectionron the first mentioned lever and a slot to permit motion of said lever, together with a projection arranged in the path of the projection on the toothed disk, a spring connecting the electro-magnet armature to the toothed disk by way of the slot therein, a further spring in connection with said ar -mature and a spring in connection with said locking lever with means for adjusting theA tension of said springs. l

3. Time element mechanism comprising an electro-magnet, a pi voted lever, an armature for said electroanagnet pivoted to said 1ever near one of the poles of the electro-magnet and so disposed that the gap at this pole Vshall be greater than the gap at the other pole, gearing and means for driving the same, and a tooth'cd disk mounted on the electro-magnet armature so as to be driven by said gearing.

4. 'liine clement mechanism comprising an elcctromagnet with two gaps, a pivoted s .non

lever acting as an armature and arranged in proximity to one gap, e train of gearing, one gear wheel of said train being mounted on the aforesaid armature,'a rotor disposed in the second gap and forming'with said' electromagnetf an electric mot-or, means connecting said rotor to said train of gearingy for the motor to drive the aforesaid train,' a switch and means for operating same after ALBERT AIGHELE.

Witnesses:

CARL GUERRE, AUGUST REGG.

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