US1226966A - Telephone system and apparatus. - Google Patents

Description

C. L. GOODRUM.

TELEPHONE SYSTEM AND APPARATUS. APPLICATION FILED FEB-3.1910.

1,226,966. Patented May 22, 1917.

2 SHEETS-SHEET I.

$ZQLM @E A445, QM a L A C. L. GOODRUM.

TELEPHONE SYSTEM AND APPARATUS.

APPLICATION FILED FEB. 3, I910- Patented May 22,1911

2 SHEETS-SHEET 2- CHARLES L. GOODRUM, OF URBANA, OHIO ASSIGNOR, BY MESNE ASSIGNMENTS, T0

WESTERN ELECTRIC COMPANY, INCORPORATED, A CORPORATTON 0F NEYV YORK.

TELEPHONE SYSTEM AND APPARATUS.

Siecification of Letters Patent.

Patented May 22, 191

Original application filed April 1, 1905, Serial No. 253,227. Divided and this application filed February 3,

1910. Serial No. 541,811.

To all whom it may concern:

Be it known that 1, Cinemas LANE (loon- RUM, citizen of the United States, residing at Urbana, in the county of Champaign and State of Ohio, have invented certain new and useful Improvements in Telephone Systems and Apparatus, of which the following is a specification.

My present invention relates to and has for its object toprovide improved electromagnetica'lly operated switches adap ted particularly for use in connection with automatic telephone systems, such as the one illustrated in my prior application, Serial No. 253,227, filed April 1, 1905, entitled Telephone systems and apparatus of which this application is a division.

While switches embodying my invention may be used for purposes other than the one mentioned, they relate more particula ly to the art of telephony and are adapted to be employed in making connection between two or more telephone lines or the trunk circuits of an automatic telephone exchange arranged between and interconnecting'a plurality of such switches. The automatic switch of this invention comprises a mo mble contact member and groups of contact terminals arranged in a row with which said contact member cooperates, electromagnetic means being provided for moving said contact member past said terminals to select a group thereof, and for controlling the return of said contact member to efiect the selection of a contact terminal in the selected group.

In the drawings:

Figure 1 is a plan view of a switch con structed in accordance with my invention.

Fig. 2 is a longitudinal View thereof taken on the line 2 2 of Fig. 1.

Fig. 3 is a detail sectional view taken on the line 3 -3" of Fig. 2.

Fig. 4: is a detail of some of the contacts and the manner of supporting the same.

Similar reference characters in the several figures indicate similar parts.

In the present case, instead of employing the double motion switches commonly known as the Strowger switches" the same having been improved by Messrs. Lundquist, Ericson and others, I have adopted a very difi'erent design. In the first place,

my switches are all mounted upon l'lat bases, so they can be mounted like drawers in a cabinet; and in the second place i make them separable, one part carrying the contact banks and multiple wiring conncc ns, and the other part carrying the relays and the working magnets together with the switch arms or wipers. These second parts are provided with contact terminals which when the parts are in position register with corresponding terminals on the first parts, completing the connections of the relays. etc. These second parts are removable and all of the same kind are interclmngeablc, and as it is with these parts that a very large percentage of the troublesoccur, it is obvious that I have achieved an im ortant end by this arrangement; for in case of any trouble with the working parts of a switch, it is only necessary to slide out the defective switch body and slide in another in its place.

I have chosen to depart from the decimal system of trunking because thereby T can simplify the switches and get better results. In the ordinary Strowger switch it is customary to step up the switch arm to the row of contacts desired, and then operate a socalled rotary magnet which would carry the wiper around continuously until it rests upon an idle contact. In the present case I provide fifty contacts in the switch divided into groups of five. The groups of five small contacts are equal in angular dimension and each is overlaid by a single broad contact. Each switch has a double ratchet motion; a pawl working into a coarse ratchet first steps the wipers around to the group contact desired, clearing five of the small contacts at a jump; then an escapement pawl working into a finer ratchet (live to one of the other) steps back the wipers one step at a time in the group thus selected until the desired unit contact is reached. Thus in these switches 1 only give five trunks to a switch, and T can multiply the number of switches if desired.

In illustrating my invention I have shown the switch mechanism mounted upon a base comprising the parts E and c, divided on the line 0 the former comprising a base upon which operating mechanism is mounted, which is removable from the part c, the

latter being provided with the bank of contacts 1F and being adapted to be ri idly attached or supported on a circuit frame or within a cabinet so that the removaole part of the base E may be applied thereto.

Upon the base 6 is a row of socket con tacts H mounted in insulation, with which cooperate the contact terminals 7L mounted in a strip on the base it. These terminals 71, are used to complete the circuit to the mag nets shown on the base E hereinafter referred to.

The contact banks F are termed as an arc of a circle somewhat less than 180 and concentric. with the center or axis 7) ot the switch spindle. in the blllllin are the broad contacts 4L8 and individual trunk contacts m.

The switch mechanism comprises a progres ively movable element 6 which adapted to be advanced step by step and to this end is made circular in form and is mounted on the revcluble shaft 7), the lower end of the shaft l ing journal/ed in the base plate ll, the othe; end being journaled in abracket 0', the ends of which are extended downwardly and are detachably secured to the base plate by fastening devices. such as screws. Carried on the movable elementand insulated therefrom and from each other are contact springs or wipers indicated by 6 7F 6 7), 5 Any desired number of these ipers may be employed and they are arranged as shown one below the other and have at their rear ends segments, as indicated by 7), with which cooperate spring brushes 6 supported in an insulated holder a secured to one of the legs of the bridge. Each brush has a tail 6 for the attachment of its circuit wire and an extension 7) which receives the wiper when turned all the way around to clear it from the bank contacts and hold it in proper position for reengagcment therewith, this clearing being necessary when the plate E and its attached parts are removed from the bank. To facilitate the removal and replacing of the plate in proper alinement with the plate 0 of the banks, I provide a pair of guide tongues attached to the plate (2 and overlying the plate E when in position. The bank as a. whole is carried on tour posts best shown in Fi 's. 3 and l, and each bank of contacts is built up of insulating segments with the contacts radially interposed between them, the whole being held together by upper and lower segmental p ates f secured by through-bolts or screws 7. Connected to the lower end of the shaft 6 is a coil-spring 7) arranged in a. casing to which its outer-end is attached the tension a ppliedto the spring being suflicient to return the shaft and the parts sup ported thereon to their normal position, shown in Fig. 1', when they are released.

Cooperating with the ratchet teeth b on the wheel 6 is a pawl 7) on a dog 7), pivoted in a yoke attached to the base plate E, as shown in Figs. 1, 2 and 3. The dog has a. joint in the middle and a spring normally tending to throw it up with the pawl engaging teeth 7). looperating with this pawl to form an escap -nent is an armature lever 7) of the magnet M this lever having a chisel edge to enter the teeth and a bar b to withdraw the pawl as the edge enters by forcing up the tail 7) of the dog.

Opposite the ratchet the dog has a toe 7), with which cooperates a hook on the end of a spring 7) carried on the end of the armature lever of the release magnet M. \Vhen this armature is attracted, the pawl 72 being up, the spring reaches up, the hook takes hold of the toe and pulls down the dog, permitting the spring 7) to return the spindle 7) and all of its wipers to zero position.

In order to step the wheel 7)* around, the armature lever 7) of the magnet M carries a pawl 7) pivoted at b on said lever and having a angle-stop 7) which comes against a fixed stop 7) on the bridge 0, when the magnet is deenergized as shown in Fig. 1. A spring 79 secured at one end to a projection on the armature 7) and at the other end to some stationary part, normally tends to hold the armature 7) in retracted position as shown in Fig. 1. As the magnet M is energized its vertical lever 7) is thrown to the left against the tension of the spring 7) and a projection on the lower part thereof comes against the spring 7) to remove it from the toe 7) and thus permits the retaining pawl 7) to rise into engagement with the teeth 7). The tension of the spring 7P tends to keep the angle stop against the fixed stop 7) so that as the armature lever 7) moves, its movement will cause the pawl. 7) to swing about its pivotal point 7) until the pawl. engages with the teeth 7) and admnces the wheel 7)" a space of one notch. Each tooth on this wheel 7) will. move the cont-act arms around ver five contacts M at a jump, equal to the distance of one broad contact -18, while each tooth 6 moves the contact arms over one contact singly. As the pawl 7) pushes the wheel 7) around, the toe 7) on the upper end of the armature lever comes over in the path of and serves as a stop for the teeth on the second wheel 7/ furnishing a positive stop for each step in the rotation.

The operation of the switch is then that the action of the magnet M will advance the wipers, depending upon the number of impulses through said magnet, the pawl 7f holding the movable element in its advanced position. The action of the magnet M permits the movable element 7) to move backwardly step by step over the individual contacts 3 through the medium of its operating spring I), the number of steps back wardly depending upon the number of im pulses through said magnet M The action of the release magnet restores all the parts to their normal position by pulling down the pawl m in the manner described, and permitting the movable element 6* to move back by the action of its spring 6 until the stop 5 thereon comes against the legs of the bridge as shown in Figs. 1 and 3.

Having thus described my invention, I claim:

1. In an automatic telephone exchange switch, contacts arranged in groups, each group constituting trunk terminals, a switch contact and means to bring said switch contact into active relation with the last contact of a definite group of said contacts, and means to cause said switch contact to step backwardly until it becomes operatively associated with one or another of said contacts in said group.

2. In an automatic switch, for telephone exchanges, a series of contacts in circular re lation, a concentrically mounted arm sweeping over said contacts, and means to cause said arm to make long steps in one direction and relatively shorter steps or movements in the opposite direction.

3. In an automatic switch for telephone exchanges, a spindle, two wheels on said spindle, and two pawls cooperating with said wheels, one to set the wheels forward by long steps, and the other to move the wheels rearwardly by short steps.

4. A switch for automatic telephone exchanges comprising a base having a stationary portion and a relatively movable part thereon, a bank of circularly-arranged terminal contacts mounted on the stationary part, and a concentrically mounted element on the movable part of the base and cooperating with the contacts, means for operating said element in long steps and separate means for operating said elements in relatively shorter steps, electromagnetic de vices for controlling the respective stepping means, said stepping means being supported on the movable part of said base.

5. In a switching mechanism, a plurality of terminal contacts arranged in an are shaped row and an underlying base or support provided with parallel ways, a base plate detachably connected to the support and fitted in said ways, a revoluble element journaled on the plate to coeperate with said contacts and mechanism for operating said element comprising two sets of stepping devices, one for long and one for short steps which mechanism is also carried on the movable plate.

6. In a progressively movable switch for automatic telephone systems, the combination with a row of terminal contacts and a movable contact element cooperating therewith, a movable part havmg ratchet teeth arranged in two series in opposite di arm havmg an engaging rections, a vibratin portion to contact with one set of teeth and a pivoted pawl to engage the other series of teeth, and means for vibrating said arm as and for the purpose specified.

7. In a progressively movable switch for automatic telephone systems, the combination with a row of terminal contacts and a movable contact element cooperating therewith, ratchet wheels having relatively short and long teeth, a series of auxiliary ratchet teeth arranged in opposite directions from the teeth in the wheel, and a vibrating part having a pawl for turning said ratchet wheel and an engaging part for engaging the auxiliary teeth to prevent overthrow, as and for the purpose specified.

8. In a progressively movable switch for automatic telephone systems, the combination with a row of terminal contacts and a movable contact element cooperating there with, ratchet wheels with relatively long and short teeth and pawls for engaging the same, of a series of auxiliary teeth or stops and an engaging part operating with a pawl and adapted to engage said stops and limit the throw of said pawl when the switch is being moved in long steps.

9. In a progressively movable switch for automatic telephone systems, the combination with a row of terminal contacts and a movable contact element cooperating therewith, a movable element, and a ratchet wheel moving with said element, a spring for moving said element to its normal position, a holding pawl operating against the tension of said spring, and an escapement pawl adapted to operate in connection with said holding pawl to permit the wheel to turn backwardly step-by-step by the cooperation of said escapement and holding pawls, as set forth.

10. In an automatic switch for telephone exchanges, groups of terminals arranged in a row, a contact arm therefor, and means to cause said arm to move over said terminal groups to the end of the desired group, and then to step backwardly to select a contact in said group.

11. In an automatic switch for telephone exchanges, sets of trunk terminals arranged in groups, a contact arm therefor, and electromagnetic means to cause said arm to move over said groups to the last set of terminals therein, and then to move backwardly to select a contact set in said group.

12. In an automatic switch for telephone exchanges, the combination with a selector apparatus having a movable contact member and groups of contact terminals arranged in a row with which said member cooperates,

means for moving said contact member past said contact terminals to select a group thereof, and means for controlling the return of said member to effect the selection of a contact terminal in the selected rou 3.

18. In an automatic switch for telephone exchan e systems, the combination with a selector switch comprising a spring-retracted movable brush and a row of line terminals arranged in groups, electromagnetic means for moving said contact member past said terminals to select a group thereof, and an escapement mechanism including a magnet to release said brush step by step to effect the CHARLES L. GOODRUM.

lVitnesses CHAS. I. lVELoir,

0L1 VER T. CLARKE.

Gopies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents. Washington, D. G.

Images