US1681558A - Electric switch - Google Patents

Description

Aug. 21, 1928.

J. SCHLAGENHAU FER ELECTRIC SWITCH Filed 001,. 4, 1923 F-ic i 2% 0| ..u n 2%? 0M w u e 3 M H F e mu 5 vb Patented Aug. 21, 1928.

UNITED STATES PATENT cr es.

J'OSEF SCHLAGENHAUFER, 0F MUNICH, GERMANY, ASSIGNOR, BY MESNE ASSIGN- MENTS, TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

ELECTRIC SWITCH,

Application'filed October 4, 1923, Serial No. 666,548, and in Germany November 25, 1922.

My invention relates to switch mechanism, and more particularly to motor starting switches of the type which are arranged to establish one set of connections for starting the motor and another set of connections for normal running operation of the motor, such as the star-delta switch or the like. In switches of this typeit is desirable that the switching operations be effected pos tively and quickly in a definite order and 1f this order of movement is in any way confused the protective fuses in the motor circuit may be burned out, or worse still, damage may be done to the motor windings or coils.

The object of my present invention is to produce a switch mechanism whereby these defects are avoided and which moreover is so constructed'that the circuit is broken and closed instantaneously.

In the accompanying drawings in which I have shown by way of example an embodiment of my invention in a manually operated star-delta motor starting switch having an off, a starting and a running position, Fig. 1 is a sectional elevation of such a switch constructed in accordance with my invention, Figs. 2 and 3 show the locking mechanism for the manual operating lever or handle of the switch in two different positions, Figs. 4, 5, 6 show the relation of the several parts of; the switch operating mechanism with various positions of the manual operating switch lever, Fig. 7 is a diagram of the electric ci.1- cuitof the motor starting switch, and Fig. 8 is a section along AB in Fig. 1, shown in the direction of the arrow C in said figure.

On the usual contact operating shaft 1 of the starting switch illustrated in Fig. 1 is mounted for independent rotation the manual operating switchhandle or lever 2, the lower end of which as shown in Fi 4 is formed in the shape of two cam surf aces provided with different curves. In the path of these curves are the thrust locking pins 3 and 4, guided by pivots which are mounted to slide under the action of biasing springs 5 and 6 so that the pins 3 and 4tendito enter notches e, f, g, provided in a cooperating locking disc formed'integral with the disc lever 9 which is suitably securedto the switch shaft 1. The locking pins 8. and 4 have suitable extensions which are arranged to slide upon the cam shaped curves of the lower endof theswitch lever 2 so that'the operation'of the pins 3 and 4 into thenotches e, f, g, of the cooperating locking disc on the disc lever 9 is controlled by the position of the cam portionof the switch lever 2.

The manual operating lever 2 is operable between an ofi, a starting and a running position and is arranged to operate the disc lever 9, and hence the contact members 11, through the agency of a flexible spring 7 Preferably the spring 7 is disposed around the switch shaft 1 with the ends thereofextending on opposite sides of the pins 8 and 10, carried respectively by the manual operating lever 2 and the disc lever 9. The arrangement is such that if the switch lever 2 is turned from the off position in which it is shown in Fig. 4 to the left, the limb z of the spring 7 is carried along by the pin 8, whereas the other limb is of the said spring will bear against the pin 10 provided on the disc lever 9. Consequently, a tension will be produced in the spring 7 which tends to move the disc lever 9 in the same direction as the switch lever 2 is moved. The tension is maintained in the spring 7 due to the fact that the pin 3*engages with the notch e which is provided in the disc portion of the lever 9, and thus prevents movement of the latter. Upon further rotation of the switch lever 2, the pin 3 will be lifted out of the notch e by the cam surface 1 sothat the'disc lever 9 is'released. This permits the lever 9, together with the switch shaft 1 and the switch blades 11 to be whirled around by the spring 7 until the locking pin 4 enters the notch 9 shown in Fig. 5. It will be understood that after the portion m of the cam surface passes the locking pin 4, the latter will be free to engage with the cooperating disc portion of lever 9, while the pin. 3 is maintained out of locking relation with the notch g by the cam surface 1. When the switch lever 2 is now rotated to the right to the position in which it isshown in Fig. 6, the following occurs V 1 As the switch operating lever 2fis turned back over an arc of 180 the pins 3 and 4 remain in their respective positions as shown in Fig. 5 until after the pin 3 passes over the inclined portion of the cam surface 1 and enters the notch 9. Due to the pivotal mounting of locking pin 4, a slight pivotal movement thereof occurs when the switch lever 2 is operated to the right. This permits the pin 3 to enter notch 9 before, a little later, pin 4 is lifted out of the notch g by the ascending portion m of the cam surface above referred to. As the manual operating lever 2 is moved to the right it will be evident that the limb is of the spring 7 will be carried along by the pin 8 while the limb z' of the spring will engage with and bias the disc lever 9 to fol-.

low the movement of the manual operating lever 2. The disc lever 9, however, is held in the position shown in Fig. 5 first by the pin 4 engaging the notch g and then by the pin 3 engaging the notch 9 until the latter is withdrawn from the notch g by the projection n. This releases the disc lever 9 secured to the shaft 1 which, together with the switch blades 11, is rapidly whirled around until the locking pins 3 and t both enter the notch f on the switch operating lever 9 as shown in Fig. 6.

When the manual switch lever 2 is moved back to its initial position as shown in Fig. 4:, pins 3 and 1 are lifted out of the notch upon respectively engaging with the projection n and the ascending portion 7) of the cam surface. The pin 3 then quickly drops back to reengage the notch e and arrest the switch operating lever 9 when it reaches the position shown in Fig. 4. s

It will be observed that the action of the spring 7 is uniform in both directions and serves to quickly and positively rotate the switch shaft 1 and the switchhlades 11 between the circnit-closing and the circuit-opening positions.

Fig. 7 shows schematically the usual circuit connections of a star-delta motor starting switch which may be employed with my improved form of switch illustrated in Fig. 1. Fig. 8 shows the relative positions of the sev eral operating parts of my improved switch mechanism at the moment when the pin 3 is lifted out of the notch e and the pin 1 is lowered toward the cam surface. This figure also shows the'action of the spring 7 In order to insure the proper sequence of operation and to maintain the manual switch operating lever 2 in its respective off, starting and running positions, the switch mechanism I may be provided wlth a locking mechanisn'i constructed as shown in Figs. 2 and The locking mechanism comprises a locking dog 12 which is pivotally mounted upon the switch lever 2 and is biased by means of suitable springs as indicated in the drawing to a central position. The locking dog 12 is arranged to cooperate with notches formed in the partition l l which separates the switch operating mechanism'from the switch contact mechanism as shown in Fig. 1. A notch of the form shown in Fig. 2 is provided in the partition let for maintaining the manual operating switch lever 2 in the central or off position. It will be observed that in this position of the arm 12, movement of the lever 2 towards the right is impossible and only a switch movement toward the left can-be effected. In both the starting and the running positions of the switch lever 2, the notch in the partition 14 is so shaped that the locking dog 12 can swing freely to one or the other side as shown more in detail in Fig. 8; This locking mechanism insures that the switch lever 2 is operated first to the starting and then to the running position and at the same time permits the switch lever to be returned to the centralor ofi' position. The locking mechanism operates in the following manner Then the manual operating lever 2 is moved from the central or ofl position to the left it will be evident that the locking dogl2 yields to the right and slides along the partition 14 until it engages the notch in the partition at the starting. position as shown in Fig. 3. Upon the engagement of the locking dog 12 with the right hand-sloping side of the notch the return of the switch lever 2 to the central or off position isprevented. However, upon a slight further movement of the lever 2 to the left, the locking dog 12 is permitted to rotate to its central or biased'position and a return movement of the switch lever 2 to the right serves to depress the locking dog 12 to the left, in which position it easily passes the central or off position notch shown in Fig. 2 and slides along the face of partition 14; until the left hand sloping edge of the notch located in the partition at the running position is encountered. The switch lever 2 is maintained in the runnin'gposition b engagement of the dog 12 with the left han sloping edge of the notch ina manner similar to that previously described. Astill further movement of the switch lever 2 to the right again permits the locking dog 12 to move to its central or biased position, thereby permitting return movement of the switch lever 2 to its off position in which the locking dog 12 reengages the notch in partition 14, as shown in Fig. 2.

I claim as my invention:

' 1. In a motor starting switch, the combination with contact members, of a switch lever operable in each direction from a plurality of positions, yielding means operatively connectingsaid switch lever with said con tact members, means comprising a stationary part provided with notches and a locking arm mounted upon said switch lever and adapted to engage said notches for retaining the switch lever positively in its positions, said locking arm and said notches being arranged to require movement of the switch lever in one direction from each of said positions before permitting movement of the lever in the other direction from said position.

2. 'In a switch mechanism, the combination with a movable contact member having aplurality of positions, of a switch lever movable between a plurality'of corresponding positions, a yielding connection between said contact member and said lever, and means comprising a locking member and a plurality of locking pins controlled by said switch lever to successively engage with said locking member for holding the said contact member in one position while the said switch lever is operatedfrom one position through an intermediate position to another position, each of said locking pins operating separately to hold the contact member in the said one position during a different portion of the movement of said switch lever.

3. In a switch mechanism, the combination with a movable contact member'having a plurality of positions, of a switch lever movable between a plurality of corresponding positions, a yielding connection between said contact member and said lever, a notched disc secured to said contact members, and a pair of independently operable locking pins controlled by said switch lever and arranged to successively engage with a notch in said disc for holding the said contact member in one position while the said switch lever is operated from one position through an intermediate position to another position and thereupon release the contact member for quick operation under the action of said yielding connection from said one position through the corresponding intermediate position to the position corresponding to said other position of the switch lever, said locking pins each operating to hold the contact member in said one position during a difierent portion of the movement of said switch lever.

4:. In a motor starting switch, the combi nation with a movable contact member having an off position intermediate a motor starting and a motor running position, of a switch lever movable from starting through an off to a running position, a yielding connection between said switch lever and said contact member to efiect operation of the contact member to a position corresponding to the position of the switch lever, a notched member secured to the said contact member, a pair of independently operable locking pins adapted to engage with notch in said notched member, and a cam associated with said switch lever and having surfaces arranged to successively engage said pins with a notch in said notchedmember to hold the contact member in the starting position while the switch lever is operated from the starting through the off position to the running position and thereupon release the contact member for quick operation under the action of said yielding connection from said starting position through the off position to the running position, each of said locking pins operating during a difierent portion of the movement of said switch lever to hold the said contact member in said starting position.

5. In a motor starting switch, the combi nation with a movable contact member having an off position intermediate a motor starting and a motor running position, of a switch lever movable successively between a corresponding off, a starting and a running position, a yielding connection between said switch lever and said contact member to effect operation of the contact member to a position corresponding to the position of the switch'lever, a notched member secured to the contact members, a pair of independently operable locking pins biased into engagement with each of a plurality of notches in said member, and a cam associated with said switch lever and provided with surfaces for separately controlling the operation of said pins into and out of engagement with the notches in said notched member to maintain the contact member in each of its positions until the switch lever is operated to the next successive one of its positions, said locking pins each operating separately to hold the contact member in said starting position during a different portion of the movement of said switch lever between the starting position and the running position.

6. A motor starting switch comprising contact members, a shaft carrying said contact members and operable between an oil, starting and a running position, a disc lever secured to said shaft and provided with a notch for each'of said positions, a switch lever mounted for operation to an as, a starting and a running position independently of said switch shaft, a spring connection between said switch lever andsaid disc lever for biasing the said switch shaft to a position corresponding to the position of the switch lever, a pair of independently operable locking pins each biased to engage with the notches in said disc lever, and a cam associated with said switch lever and having separate surfaces for independently controlice ling the engagement of said pins with said 1 disc lever to insure a quick operation of said switch shaft to and from said off, starting and running positions by said spring upon operation of said switch lever to the corresponding position.

In testimony whereof I affix my signature.

J OSEF SCHLAGENHAUFER.

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