US1300483A - Rheostat. - Google Patents

Description

E. PODSENICK.

RHEOSTAT.

APPLICATION FILED MAR 28. I916.

Patented Apr. 15, 1919.

Swvewtoz EDWARD PODSEN/CK, mMMe-y 6 EDWARD PODSENICK, OF BROOKLYN, NEW YORK.

RHEOSTAT.

Specification of Letters Patent.

Patented Apr. 15, 1919.

Application filed March 28, 1916. Serial No. 87,151.

To all whom it may concern:

Be it known that I, EDWARD PoDsENIcK, a citizen of the United States, residing in the borough of Brooklyn, in the county of Queens and State of New York, have invented new and useful Improvements in Rheostats, of which the following is a specification.

This invention relates to rheostats, and it is the object of the invention to provide an improved rheosta-t to cheapen the cost of construction and increase the efliciency thereof.

In rheostats as heretofore constructed it is the practice to provide a series of resistance coils connected in series and to a terminal of an electric circuit, or a coil with a plurality of contacts connected to dilierent sections of said coil and to a terminal of an electric circuit, the coil or coils and contacts being in a fixed position. The resistance coils, or different sections of a coil, are thrown into circuit by a movably supported contact connected to the other terminal of the electric circuit and adapted to be thrown successively into contact'with the re spective coils, or different sections of a coil. This mechanism is usually inclosed in a metallic box necessitating a great amount of insulation to insulate the parts from the box and requiring a great deal of time to install such insulation.

It is an object of the invention to overcome the above disadvantages and to reduce the insulation to a minimum, and with this object in view instead of providing a movable contact connected to a terminal of an electric circuit adapted to be thrown in circuit with the contacts connected in circuit with a fixed coil or coils, the said contact is supported and insulated from the inclosing box for the mechanism to have yielding movement into and out of the box, and a resistance coil or coils connected to the other terminal of the electric circuit with the connected contacts pivotally supported within the box to move as a unit and adapted to be oscillated to throw the resistance coil contacts successively into and out of contact with the contact connected to the other terminal of the circuit.

A further object of the invention is to provide a rheostat which is in the nature of a starting box for an electric motor and to provide braking means operative simultaneously with and by the means to throw the reing a part of this speci sistance coil contacts into and out of contact with the contact connected to the terminal of the circuit opposite to which the coil is connected.

In the drawing accomipanying and formcation Figure 1 is a front elevation, partly broken away, of a rheostat showing an embodiment of my inventlon.

2 is a sectional side elevation.

F 1g. 3 is a fragmentary view looking at the right of Fig. 2 to show the lever and crank connection to the coil carrier.

Fig. 4 is a diagrammatic view illustrating the relationship between the various parts of the electric circuit.

Similar characters of reference designate like parts throughout the different views of the drawing.

In the embodiment of my invention shown in the drawing the operative parts are carried and inclosed by a casing 4, preferably circular in, shape, open at one end which is closed by a. removable cover 5, said cover having an opening with a. wall 6 extending laterally from said opening and the opening closed by a removable plate or cover 7. The casing proper t has standards 3 whereby it is secured to a suitable support.

Secured in the opening of the cover 5 is a panel of insulating material 8 carrying a terminal post 9 to which is connected one terminal 11 of a conductor connected to a source of power, said conductor passing through an opening in the plate 7 having an insulating lining or eyelet 12. The said panel has a terminal post 13 to which is connected the other terminal 14 of the current conductor connected to the source of power which conductor is also passed through the eyelet 12. Slidably mounted in a bushing 15 in the panel 8 is a contact 16 in the form of a stick of carbon, to have movement into and out'of the casing, the said contact being carried by a resilient arm or spring 17 and connected therethrough with the terminal post 13, the said post 13 and clamping screw 18 serving to connect said arm to the panel.

A carrier for resistance coil or coils 19 is pivotally or rotatably supported in the casing to have oscillatory movement, said carrier comprising an annular member 20 of insulating material, preferably porcelain, having annular flange portions 21 and 22, the flange 22 being of greater area than the ing into the casing with one end of the shaft projecting out from the casing. The resistance wires or coil 19 of suitable conducting material are wound or coiled around the flanges 21, 22 of the annular member 20, as shown in Fig. 2. The coils or sections thereof are connected in series with a plurality of contacts 26 carried by the annular member 20, and are shown as six in number arranged in the arc of a. circle, only four of which are connected with the resistance wires 19, while the other two at the left of Fig. 1 and indicated by 26 are not connected in circuit with the wires for a purpose to be hereinafter described. These contacts comprise buttons of conducting material having screw threaded connection with headed binding screws 27 passing through openings in the coil carrier 20. The resistance coil or wires, or sections thereof, are connected successively to the contacts 26 through the binding screws 27. In the present instance these screws are electrically connected to different sections of the coil 19 by wires 28 which may lie in a transversely extending recess in the coil carrier as shown in Fig. 2. The first section of the resistance wires or coil is connected 'to the contact 26 at the extreme right by wire 29 and by means of the latter with the terminal post 9.

Movement is imparted to the resistance coil 'to place the contacts '26 successively in contact with the fixed contact 16 by a rod or lever 31 connected to a pin 32 fixed in a crank 33 fixed to the projecting end of the shaft 24. It will be obvious that as the lever 31 is pulled down movement will be imparted to the coil in a direction indicated by the arrow in Fig. 1, thereby successively placing the cont-acts 26 in contact with the contact 16 this movement of the coil being limited by the crank engaging with a fixed stop 34 projecting from the casing with the contact 26 at the extreme right of Fig. 1 in contact with the contact 16. As soon as the rod 31 is released the contact carrier is returned to initial position with the dead contact 26 at the extreme left of the series of contacts, as shown in Fig. 1, enga ing the cont-act 16, by a spring 35 coiled about the rod 31 and confined between a lug 36 and the crank pin 32, said spring maintaining the coil in this position with the crank 33 engaging a stop 37 projecting from the casing. It will be noted that as the contacts 26 are not in circuit with the resistance coil the circuit will be broken or opened as soon as either one of these contacts is brought into engagement with the contact 16. The contacts '26 are so proportioned and spaced apart that they will serve as a continuous track and readily slide over the contact 16, and the latter contact is at all times maintained in engagement with said contacts 26 during the movement thereof by the tension of the spring arm 17.

To utilize the rheostat as a starting box for an electric motor and simultaneously actuate braking mechanism as the rheostat is operated to throw it, out of circuit with the source of electricity to retard the movement of the motor there is connected to the lever 31 an arm 38 to have movement therewith, said arm 38 being connected to one end of a rocker arm 39 fulcrumed in a longitudinal slot, as at 43, providing adjustment for pulleys of various dimensions, and to the other end of which is connected a brake shoe 40 adapted to frictionally engage with a movable part of the motor, shown in the present instance as a driving wheel 41 of a motor. It will be noted that the spring 35 also serves to cause the shoe 40 to frictionally engage with the pulley 41 when said spring operates to return and maintain the coil in initial position, and as the coil is moved to place the contacts 26 in contact with the contact 16 by the lever 31, the brake shoe will be simultaneously thrown out of frictional engagement with the pulley 41. \Vhen the coil is moved to start the motor in motion and the shoe is thrown out of operative engagement with the pulley 41, this movement will be against the tension of the spring 35 the said spring being compressed increasing the inherent tendency of the tension of the spring to return the parts to inoperative position, and when the lever 31 is released this spring will expand, but the expanding movement of the spring will be limited thereby preventing any tendency of the spring expanding too greatly with the possibility of the breaking of the spring which is the case when the cont-racting'act-ion of a spring is utilized to return the parts to inoperative position.

In Fig. 4 there is shown diagrammatically the circuit of the various parts. The circuit passes from the source of power, such as a dynamo D, through conductor 14 to the resilient arm 17 carrying the contact 16 normally in contact with one of the contacts 26* carried by the carrier for the resistance coil. The current passes from the contact 16 to either one of the contacts 26 of the coil carrier as they are placed in contact-therewith by the movement of the coil carrier. and from said contacts through the wires 28 to the'resistance coil, and from the latter through the wires 29, 11 to the motor M connected in circuit with the source of power or dynamo D.

Having thus described my invention I claim:

1. In a rheostat, the combination of a fixed contact connected to a terminal of an electric circuit; a resistance coil connected to the other terminal of said circuit; a pivotally supported carrier around which said coil is Wound; a plurality of contacts secured to said carrier electrically connected in series and with different sections of said coil and normally out of circuit with the fixed contact; means to impart rotative movement in one direction to said carrier and thereby place said contacts successively in contact with the fixed contact; and a spring to return the carrier to initial position, substantially as and for the purpose specified.

2. In a rheostat, the combination of a fixed contact connected to a terminal of an electric circuit; a resistance coilconnected to the other terminal of said circuit; a pivotally supported carrier around which said coil is wound; a plurality of contacts carried by the carrier and insulated from the coil and electrically connected in series and With diflerent sections of the coil, said contacts being normally out of contact with the fixed contact and adapted to be placed in contact with the fixed contact; a spring to maintain the carrier in position with the coil out of circuit with the fixed contact; and a lever to impart rotative movement to said carrier against the action of the spring to place the coil contacts successively .in contact with the fixed contact, substantially as and for the purpose specified.

3. In a rheostat, the combination of a resistance coil connected to a terminal of an electric circuit; an annular carrier of insulating material for said coil supported to have oscillatory movement; a plurality of contacts carried by said carrier electrically connected in series and to difi'erent sections of the coil; a fixed contact connected to the other terminal of the electric circuit; a crank to impart rotative movement to the coil carrier to place the contacts carried thereby successively in contact with the fixed con-j tact,-and a spring to impart return movement to the coil carrier, substantially as and for the purpose specified.

4. In a rheostat, the combination of a resistance coil connected to a terminal of an electric circuit; an oscillatory annular carrierof insulating material for said coil; a plurality of contacts carried by said carrier electrically connected in series and to different sect-ions of the coil; a fixed contact connected to the other terminal of the electric circuit; a crank connected to the coil carrier; a rod connected to the crank to operate the coil carrier and successively place the contacts carried thereby in contact with the fixed contact; and a spring to return the carrier, substantially as and for the purpose specified.

5. In a rheostat, the combination of a casing; a contact arranged to be connected to a terminal of an electric circuit insulated rom and supported by the casing to have yielding movement into and out of the casing; a resistance coil pivotally supported Within the casing connected to the other terminal of the electric circuit; a plurality of contacts movable with the coil connected in series and to different sections of said coil, and at least one of which contacts is not in circuit with the coil and normally in contact With the contact carried by the casing; and means to impart movementto the coil to place the connected contacts successively in circuit with the contact carried by the casing, substantially as and for the purpose specified.

6. In a rheostat, the combination of a casin having an opening in one end; a remova le cover for said opening; a contact connected to a terminal of an electric circuit carried by and insulated from the cover to have yielding movement through said cover into and out of the casing; a resistance coil in the casing connected to the other terminal of the electric circuit; a carrier for said coil; a plurality of contacts carried by said carrier certain of which contacts electrically connected in series and to different sections of the coil; a spring to normally maintain the carrier in position pivotally supported with a contact not in circuit with the coil in contact with the contact carried by the cover; and means to move the coil against the tension of the spring to place the contacts carried thereby successively in contact with the contact carried by the cover, substantially as and for the purpose specified.

7 In a rheostat, the combination of a casing having an opening in one end; a removable cover for said opening having an opening with a panel of insulating material therein; terminal posts for an electric circuit carried by said said panel to have yielding sliding movement 1n an opening in said panel into and out of the casing and electrically connected to one terminal post; a resistance coil pivotally supported within the casing connected to the other terminal post carried by the panel; a plurality of contacts movable with the coil certain of which contacts are electrically connected in series and with different sections of the coil and at least one of which contacts is not connected with the coil and which contact is adapted to normall be in contact with the contact carried liy the panel; and means to move said coil to place the contacts connected in circuit therewith successively in circuit with the contact carried by the cover, substantially as and for the purpose specified.

8 In a rheostat, the combination of acasing having an open end; a cover to close said opening having an opening with a panel of insulating material therein; terminal post-s for an electric circuit carried by said panel; a contact carried by panel; a contact sliclably mounted in an opening in said panel; a resilient arm carrying said contact to connect it to one of the terminal posts and te-nsioned to normally move the contact into the casing; a resistance coil within the casing connected to the other terminal post carried by the panel; a carrier of insulating material for said coil having means to pivotally support the same in the casing; a plurality of contacts carried by said carrier certain of which contacts are electrically connected in series and with different sections of the coil, and at least one of EDWARD PODSENICK.

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