US1229635A - Snap-switch. - Google Patents

Description

lF. W. &'W. A. MARSCHKE.

SNAP SWITCH.

APPLICATION min SEPT. 1l, 1916.

,229, 63 5.. Patented June 12, 1917.

2 SHEETS-SHEET l.

F. W. L W. A. MARSCHKE.

SNAP SWITCH.

APPLICATION FILED SEPT. II. I9I6.

lw. mmm Jun@ 12, 1917.

2 SHEETS-SHEET 2.

.y M y Y UNITED STATES PATENT OFFICE.

FREDRICII w. ivianscnxn AND WILLIAM n. ivmnscHKn, or INDIANAPOLIS, IIvnIANA.

SNAP-SWITCH.

Original application filed December 24, 1915, Serial No. 68,498, now Patent No. 1,221,345.

application filed September 11, 1916.

To all wlw-m t may concern.

h Be it known that we, FREDRICII WV. MARsoHkn and WILLIAM A. MARsoHKn citizens of the United States, residing at Indianapolis, in the county of Marion and State of Indiana, have invented a new and useful Snap-Switch, of which the following is a specification.

It is the object of our invention to provide a starter for electric motors, which shall be simple and inexpensive, eflicient andsure in operation, and will serve to make and breakthe circuit by a snap switch action-and automatically to increase the electro-motive force impressed on the motor after the closing of the circuit; and to make the apparatus readily controllable by the operators foot so that he may have his hands free from other work. y

This application isdirected primarily to the switch structure, and is a division of our co-pending application Ser. No. 68,498, filed December 24, 1915, on which Patent No. 1,221,345 was granted April 3, 1917, and in which patent themotor controller is claimed.

The accompanying drawings illustrate our invention. Figure 1 ris a front elevation of a starter embodying our invention, showing in section the oil tank in which the switch contacts are immersed; Fig, 2 is a side elevation of such starter, with the oil tank partly in section and the switch open; Fig. 3 is a detail showing the releasable connection between the rheostat rod and its lifting mechanism; and Fig. 4 is a detail of the switch taken from the same viewpoint -as Fig. 2, but with the switch closed. Y

A suitable upright support y10 carries near its lower end an oil tank 1.1 in which is mounted a 'horizontalshaft 12 on which are fixed two movable knife blade contacts 13 and 14, which are insulated from the shaft 12 by insulation 15. The lower ends of these knife bladesf13 and y14 are movable into and out of engagement with Afixed contacts 17 and 18, suitably mounted on insulation 19 with-inthe oil tank 11 and connected by metal strips 21 and 22 to binding posts 23 and 24 atvthe top of the oil tank 11. The movable blades 13 and 14 are provided with binding posts 25 and 26.

On .one end of the shaft 12, outside the oil tank 11, is fixed a T-shaped member having an upwardly extending arm 31, a forwardly extending` arm 32, anda downwardly Patented J une 1.2, 1917.

Divided and this Serial No. 119,391.

extending arm 33. The upwardly extending arm 31 is connected by a tension spring 34l to a fixed pin 35, suitably carried in the stationary frame work, yand by a tension spring 36 to the upper end of an arm 37 fixed'on a shaft 38 suitably supported below the oil tank 11 and provided with a forwardly extending arm 39 carrying a foot piece 40 so that it can readily lbe operated by the operators foot. The springs 34 and 36 extend in opposite directions from the karm 31, and are normally balanced in their action on such arm. The forwardly extending arm 32 of the T-shaped member carries a roller 41 which may'ride yon either the upper or lower surface of a lprojection 42 carried by the arm 37, so asto prevent movement of the shaft 12 save when the arm 37 is in one or the other of its extreme positions. The arm 37 and foot lever 39 are suitably biased in a clockwise direction (Figs. 2 Aand 4), as by the weight of associated parts `(of which more hereafter), or by a tension spring43 connecting such lever and a fixed pin 44 suitably supported on the main frame. The downwardly extending arm 33 of the yT-shaped member is provided with an inturned flange 45 which strikes a cushion 46 ymounted on the side of the oil tank 1l to take the shock when the switch is opened as hereinafter described.

- When the foot lever 39 is in its normal position, the springs 34 and 36 are both contracted and the T-shaped member is yin the position shown in Fig. 2, withthe switch open. Vhen now the operator steps on the foot piece 40 and depresses the lever 39, he tends to stretch both springs 34 and 36, but before there is any material movement of the T-shaped member the upper surface of the projection 42 passes under ,the roller 41 and prevents such T-shaped member and the movable switch contacts from moving in a counterclockwise direction (Figs. 2 and 4), until ,the foot lever 39 and lever 37 have about reached their limit of movement in' that same direction. By this time, the spring 36 is well tensioned, and the spring 34 is still under practically no tension. When the lever 37 reaches its limit of movement as aforesaid, the projection 42 passes out from under the roller 41, being shown just on the verge of doing so in dotted lines in Fig. 2, whereupon the restraining action on the T-shaped member and movable switch contacts is removed and the spring 36 contracts to throw the shaft 12 and parts carried thereby to the 4position shown in Fig. 4,`or in other words to close the switch, whichis done with a snap actio-n. l/Vhen now the operator releases the footlever39, such foot lever and the arm 37 return in a clockwise directiony from the position shown in full lines in Fig. 4 toward the position shown in full lines in Fig. 2, being moved in such direction by reasonof their aforesaidbias.

y As this movement starts, there is a tendency to diminish the tension on both spring 34 and 36, but before there can vbe any material movement of the shaft 12 and parts carried thereby, the under surface of the projection 42 passes over the roller 4l and effectually locks the shaft k12 and its associated parts from movement until the arm 37 ypractically reaches its limit of movement in a clockwise direction (Figs. 2 and '4). When the arm 37 does reach its limit of-movement in such Y clockwiser direction, the proj ection' 42 passes Mounted-on a strip of insulation 50 carried by the frame l above the oil tank 11 are a series of contacts 51 and a single contact 52 opposite them, and the single Contact 52 may be connected to any one of the series of contacts 51 vby a cross-connectingbar 53 having carbonbrushes 54 which arefspring- "pressed outward into engagement vwith the contact 52 and the series of contacts 51. The cross-'connecting bar. 53 is carried by and. insulated from a vertically reciprocable rod 55, which also carries a laminated contact piece 56 which when the cross connecting bar 53 is in engagement with the lowermost contact 51,v interconnects two stationary contacts 57 and 58'carried by the insulation and connected to such lowermost contact 51 and to the contact 52 respectively. On the lower end of the reciprocable rod y is the piston of a dash pot 60, which retards downward movement of the rod 55 while permitting a free upward movement thereof, in theA fusual manner of such dash. pots. The rod 55 Vis prevented from turning by a screw 61 which projects into a longitudinal slot in the rod 55. The upper end of the reciprocable rod 55 is provided with a circumferential shoulder 63, which may be cngaged byk teeth 64 carried by flat springsy 65 which join a collar 66 freely slidable on the rod. 55'and a yoke 67 carried by a lever 68 pivoted on a fixed `pin 69 near the top of the` main frame 10. The springs 65 are alsoV provided with cams 70 'which when the yoke 67 is moved upward engage a cammingmember 71 fixed in proper position on the main frame 10` and spread the springs 65 apart so as to disengage the teeth 64 from theshoulder 63. The lever 68 is suitably biased in a counterclockwise direction (Fig. 1) as by a tension spring 72, but is connected by a link 73, a lever 74, and a link A75 of adjustable length to a rearwardly eX- 'tending arm 79 from the arm 37, so that as the foot lever 39 is depressed to move the arm 37 from full to the dotted line positions shownin Fig. 2 the lever 68 is moved from the full to the dotted line positions in Fig. 1, and vice versa. It is in the dotted line position yof the lever 68 (Fig. 1) that ytheteeth 64 are disengaged from the shoulvder 63.

The binding posts 24 and23 are connected by wires and'81'to the supply mains 82. The binding post 26l isconnected by* a wire 831to one terminal of the ield windings 84 and also to one 'brush of the armature 85 of the motor to be controlled. The other brush of the armature 85 -is connected by a wire 86 to a binding post 87 on the contact 52. The other terminal ofthe field windings 84 is connected by a wire 88 to a binding post 89 on the insulation 50. `The binding post 89 is connected by a wire 90 to thelowermost of the contacts-51, and by a' wire 91 to the binding post 25. A variable resistance 92 has its ends connected to the uppermost and lowermost of the contacts 51 Iand intermediate points alongit connected tothe intermediate contacts 51. l

When the operator depresses the foot lever 39, he movesA the arm 37 from the full line positionY shown in Fig. 2 to the full line position shown'y in Fig. 4, and at the same time moves the lever 68 andthe reciprocable rod 55 and' associated parts from the'full line to the rdotted line position shown in Fig. 1. The reciprocable rod rreaches its uppermost position, with the cross-connecting bar 53 in engagementfwith the upperymost contact 51, vat yabout the time the projeetion '42 passes out of engagement with f the roller 41 and allows theswitch to snap closed to close the motor circuit, so that the entire resistance 92 is in thecircuit of the armature4 85 and reduces'the electro-motive force impressed on such armature from that of the supply mains 82.A At about the same time that the switch snaps closed, the camming member 71 and cams 7 O cause the teeth 64 to be disengaged from the shoulder 63, thus disconnecting ythe reciprocable rod 55 from the lever 68 and allowing such rod to start downward7 under the action of gravity andv retarded byl the dash pot 60. vAs the reciprocable yrod 55 movesl downward, it

comes successively into engagement with the contacts 5l, thus cutting out the sections of the resistance 92 and progressively increasing the electro-motive force impressed on the armature 85, but doing so suiiiciently slowly to allow the motor to gain in speed suliiciently to develop a counter electromotive force suilicient to prevent too great a current through the armature. When the cross-connecting bar 53 reaches they lowermost contact 5l, the laminated contact 56 interconnects the contacts 57 and 58, and as the whole resistance 92 is now cut out the full electro-motive force of the mains 82 is impressed on the armature 85.

XV hen it is now desired to stop the motor, the operator releases the foot lever 39, allowing the parts to return to their normal position and the switch to open, and causing the teeth Gtagain to engage the shoulder 63 to reconnect the reciprocable rod and lever 68 for the next starting operation.

l/Ve claim as our invention:

l. An electric switch, comprising the combination of a movable switch member, two tension springs acting opposite directions on said movable switch member, a movable operating member between which and said movable switch member one of said springs is connected, cooperating projections on said movable switch member and said movable operating member for preventing the opening or closing movement of said movable switch member as the movable operating member travels through an intermediate portion of its movement in either direction, and a second switch member cooperating with the first.

2. An electric switch, comprising the combination of a movable switch member, two springs acting in opposite directions on said movable switch member', a movable operating member between which and said movable switch member one of said springs is connected, coperating projections on said movable switch member and said movable operating member for preventing the opening or closing movement of said movable switch member as the movable operating member travels through an intermediate portion of its movement in either direction, and a second switch member coperating with the first.

3. An electric switch, comprising the combination of a pivoted switch member, a second switch member coperating with said pivoted switch member, two tension springs acting on said switch member and tending to throw it in opposite directions, a pivoted operating member biased in one direction and between which and said pivoted switch member one of said tension springs is connected, and two coperating projections carried by said pivoted switch member and said pivoted operating member and interlocking to prevent movement of said pivoted switch member during the movements of said pivoted Operating member in either direction until such movement of the pivoted operating member is nearly completed.

4L. An electric switch, comprising the combination of a pivoted switch member, a second switch member coperating with said pivoted switch member, two springs acting on said switch member and tending to throw it in opposite directions, a pivoted operating member biased in one direction and between which and said pivoted switch member one of said springs is connected, and two coperating projections carried by said pivoted switch member and said pivoted operating member and interlocking to prevent movement of said pivoted switch member during the movement of said pivoted operating member in either direction until such movement of the pivoted operating member is nearly completed.

5. An electric switch, comprising the combination of a pivoted switch member, a second switch member cooperating with said pivoted switch member, two tension springs acting on said switch member and tending to throw it in opposite directions, a pivoted operating member between which and said pivoted switch member one of said tension springs is connected, and two cooperating projections carried by said pivoted switch member and said pivoted operating member and interlocking to prevent movement of said pivoted switch member during the movement of said pivoted operating member in either direction until such movement of the pivoted operating member is nearly completed.

6. An electric switch, comprising the coinbination of a pivoted switch member, a second switch member cooperating with said pivoted switch member, two springs acting on said switch member and tending to throw it in opposite directions, a pivoted operating member between which and said pivoted switch member one of said springs is connected, and two coperating projections carried by said pivoted switch member and said pivoted operating member and interlocking to prevent movement of said pivoted switch member during the movement of said pivoted operating member in either direction until such movement of the pivoted operatinO' member is nearly completed.

An electric switch, comprising the cornbination of a shaft, a switch blade carried thereby, a switch contact coperating with said switch blade, a member iXed on said shaft and having two projecting arms, a pivoted operating member, a tension spring interconnecting said pivoted operating member and one of said arms, a tension spring acting in the opposite direction on said shaft from said first tension spring, and two cooperating projections carried by said piv-4 oted operating member and by said second arm and interlocking to prevent movement of said shaft in either direction during an intermediate part of the movement of said operating member in either direction.

8. An electric switch, comprising the combination of a shaft, a switch blade carried thereby, a switch contact coperating With said switch blade, a member fixed on said shaft and having tivo projecting arms, a pivoted operating member, a spring interconnecting said pivoted operating member and one of said arms, a spring acting' in the opposite direction on said shaft from said lirst spring, and two cooperating projections carried by said pivoted operating member and by said second'arm and interlocking to prevent movement of said shaft in either direction during an intermediate part of the movement of said operating member in either direction.

In Witness whereof, We have hereunto set our hands at Indianapolis, Indiana, this ninth day of September, A. D. one thousand nine hundred and sixteen.

FRIEDRICH W. MARSCHKE. WILLIAM A. MARSCHKE.

Copies of this patent may be obtained for ve cents eachyby addressing the Commissioner of Patents, Washington, D. C.

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