US549597A - Combined rheostat and reversing-switch for electric motors - Google Patents
Combined rheostat and reversing-switch for electric motors Download PDFInfo
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- US549597A US549597A US549597DA US549597A US 549597 A US549597 A US 549597A US 549597D A US549597D A US 549597DA US 549597 A US549597 A US 549597A
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01C—RESISTORS
- H01C10/00—Adjustable resistors
- H01C10/30—Adjustable resistors the contact sliding along resistive element
- H01C10/32—Adjustable resistors the contact sliding along resistive element the contact moving in an arcuate path
Definitions
- My invention relates to an improved combined rheostat and reversing-switch for electrio motors, the object of the invention being i to so construct an apparatus of the nature above specified as to reduce the cost of manufacturing the same to a minimum.
- a further object is to construct and arrange theapparatus in such manner that it shall be ing devices.
- the invention also consists in the combinatiornwith a reversing-switch for a motor and operating devices, of a rheostat controlled by the operation of said operating devices, said rheostat being so constructed and arranged that the resistance material will be switched out of circuit when the operating devices are turned'in either direction from their normal position.
- the invention further consists in the combination, with. a reversing-switch and operating devices, of a rheostat hearing such. relation to said operating devices that when the operating devices are operated at either side of their normal position the switch will be operated and more or less resistance material gradually switched into or outot circuit.
- the invention also consists in a rheostat composed of a coiled conductor having insulating material between its convolutions and having a transverse path over said convolutions for a contact device.
- the invention also consists in certain novel arrangements of parts,as hereinafterset for th, and pointed out in the claims.
- Figure l is a face view.
- Fig. 2 is a vertical cross-section.
- Fig. 3 is a side view.
- Fig. i is a plan view.
- Figs. 5 and 6 are views illustrating the switch devices.
- Fig. 7 is a detail 'view of the resistance-coil.
- Figs. '7 and 7 are detail views.
- Figs. 8 and 9 are views illustrating modifications.
- ratus and comprises counterpart platesa a, secured together by means of bolts?) 1 I) I) and c, the latter being insulated from the platesv a by means of an insulating-sleeve 0.
- tray being made'in two parts. and provided with perforations for the pa'ssageof the bolts 1), insulating-sleeves cdbeing inserted within said perforations, so'as to insulate the. tray from said bolts b, and at the ends of said sleeves washers c are disposed between the tray and frame, so as to insulate these parts from. each other.
- the tray B is constructed to receive a resistance-coil 0 between its members, said coil and tray being insulated from (each other by means of suitable insulating resistance material, and between its convolutions insulating material e (such asmica) is placed.
- the resistance-c0110 is preferably provided terial, and said coil is milled across the face to produce a contact-path g, with which a brush, (similar to a commutator-brush, hereinafter described, makes contact.
- the contact-path g is preferably made in the arc of a circle, extending outwardly from. opposite sides of the non-conducting center or hub f, so as-to accommodate the contactbruslnwhich I prefer to attach to a pivoted .leverD.
- the leverl is pivotally connected between its ends with the bolt 0 and insulated therefrom by the sleeve c-.
- the upper end of the. lover-.1.) is provided with a locking pin having a handle it, said pin.
- the material (I.
- the coilC preferably composed of ribbon of German silver or other suitable with ahub or centerf, of non-conducting matact-brush in engagement with the hub 01' disk f in the center of the resistance-coil; Stops h are adjustably secured to the quadrant k wherebyto limit the throw of said lever, said stops being serrated or toothed on their under faces to engage similar serrations or teeth 7v" on the quadrant.
- a plate i of fiber or other insulating material
- said insulating-plate being made with an elongated slot 11
- a metal plate 2' is secured and provided at its upper end with a lug i having a screw-threaded perforation for the reception of the lower end of a rod 2 the upper end of which is electrically connected with the bolt
- a metal bracket 2' is secured by means of bolts 77, said bolts passing through'an elongated slot 2' in said metal plate i whereby to enable said bracket to be adjusted vertically.
- a rheostat constructed as above described is very cheap, since the cost of winding the ribbons of the spiral conductor and interposed insulation, and finishing the contact-path is very small.
- a further advantage of my improved construction is that there are from twenty-five to forty contacts per inch, depending upon the thickness of the conductor used, and therefore the number of contacts is so great as to reduce the voltage between the contacts to so small an amount as to entirely eliminate the sparkingwhich takes place in rheostats as they have heretofore been constructed;
- the lower end of the levei D is provided with a roller is, adapted to enterthe forked 01' bifurcated end of an armor lever F, secured to a rock shaft F, which latter is mounted in the lower portion of the framework-of the apparatus and at its opposite 8 5 end is provided with an armG, having a bifurcated upper end, for a purpose hereinafter explained.
- Brackets Z are secured toithe base II, and to these brackets switclrlevers I I are pivot-' ally connected at points near their lower ends, and adapted, Dealt-their upper ends to engage "contacteplates mm; projecting from contact-blocks mimi'; To the lower end of each switch-lever.
- a link at is connected, and said links are connected together by means of a bar or bars '01, of non-conducting mate rial, said her or bars being provided with a a pin or pins 0, which enter the bifurcated end of the lever or arm G.
- the switch-levers I are also adapted to engage the respective ends of a contact-plate o, secured to a contact-block 0 secured to the center of the base H, one of said switch-levers being normally in contact with said contact-plate '0 and the other switch-lever being normally in Contact with oneof the contact-plates m, and by connecting the short arms of the switchlevers by the bar a when the latter is moved longitudinally ,both switch levers will be shifted simultaneously to reverse the current through themotor with which the apparatus is connected.
- each switchlever is provided at its free end with an arcingtip 3, of carbon or similar materiahadapted to engage the arcing-rollers, the latter being normally retained in their normal positions by means of springs 15, secured at one end to the arms in which the rollers are mounted and at their other ends to the contact-blocks.
- the reversing-switch constructed as above explained is quite similar to reversingswitc'hes as heretofore constructed, except IIO that it is provided ii'ith an additional. fea-' t1ire-viz., arc-rupturing contacts so placed that the circuit will always be made andi broken between these contacts in'preferenceto making and breaking at themain contacts,
- rock-shaft F rock-shaft F, lever or arm G, and connect-' lug-barn to shift the said' switch-levers and reverse the current through the motor.
- the reversing-switch is set in one direction, thus causin g the current to pass through the armature from that direction, and as the lever D is gradually thrown over the resistance will be cutout gradually by the contactbrush i working over the ribbon.
- the breaking of the circuit is done on the arcing-rollers, thus preventing sparking at the switch contacts.
- the lever D is thrown in the reverse direction, the reversing-switch is also thrown over, causing the current to pass through the motor in the opposite direction, the contact-brush E cutting out the resistance, as before".
- contact-path may be made straight across the face of the coil or exactly in line with the diameter thereof, as shown in Fig. 9.
- the resistance-coil instead of being made round may be wound in rectangular form, as shown in Fig. 8.
- said brush being adapted to engage and pass over the convolutions of the resistance coil, a pin carried by said lever and adapted to enter the socket in said quadrant, and stops adjustably secured to said quadrant to limit the movement ofsaid pivoted lever, substantially as set forth.
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Description
(No Model.) 4 4 Sh'eets-Sheet'1.
I J. P. B. FISKEQ COMBINED RHEOSTAT AND REVERSING SWITCH FOR ELEGTRIG MOTORS.
No. 549,597 Patented Nov. 12,1895.
. 4 SheetsSheet 2.
(No Model.)
J. P. B. FISKE. v COMBINED RHBOSTAT'AND REVERSING SWITCH FOR ELECTRIC MOTORS.
Patented Nov. 12,1895.
ERSC sumarmv n c (No Model.) 4 Sheets-Sheet 3.
' J. P. B. FISKE. GOMBINE-D RHEOSTAT AND REVERSING SWITCH FOR ELECTRIC MOTQRS.
,59'7. Patented N0v. 12,1895.
WWW \XWIIZIIIMHII (No Model.)
J.P.. B. PIS-KB. COMBINED RHEOSTAT AND REVBRSING SWITCH FOR'ELEGTRIG MOTORS.
4 Sheets-Sheet 4.
No. 549,597. Pate ited Nov. 12,1895.
UNITED STA ES I PATENT. OFFICE.
.ToNA'rnAN r. n. FISKE, or ALLIANCE, onto.
COMBINED RHEOSTAT'AN D REVERSlNG-SWITCH FOR ELECTRIC MOTORS.
SPECIFICATION forming part of Letters Iatent No. 549,597, dated November 12, 1895. Application fil d November 6, 1894' Serial No. 528,053. [N0 model.)
To all whom .it'mag concern.-
Be it known that I, JONATHAN P. B. FlSKE, a resident ofAlliance, in the county of Stark and State of Ohio have invented certain new and useful Improvements in a Combined Rheostat and Reversing-Qwitch for Electric -Motors; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as Will enable others skilled in the art to which it appertains to make and use the same. 7.
My invention relates to an improved combined rheostat and reversing-switch for electrio motors, the object of the invention being i to so construct an apparatus of the nature above specified as to reduce the cost of manufacturing the same to a minimum.
' A further object is to construct and arrange theapparatus in such manner that it shall be ing devices.
The invention also consists in the combinatiornwith a reversing-switch for a motor and operating devices, of a rheostat controlled by the operation of said operating devices, said rheostat being so constructed and arranged that the resistance material will be switched out of circuit when the operating devices are turned'in either direction from their normal position.
The invention further consists in the combination, with. a reversing-switch and operating devices, of a rheostat hearing such. relation to said operating devices that when the operating devices are operated at either side of their normal position the switch will be operated and more or less resistance material gradually switched into or outot circuit.
The invention also consists in a rheostat composed of a coiled conductor having insulating material between its convolutions and having a transverse path over said convolutions for a contact device. I
. The invention also consists in certain novel arrangements of parts,as hereinafterset for th, and pointed out in the claims.
. In the accompanying drawings, Figure l is a face view. Fig. 2 is a vertical cross-section. Fig. 3 is a side view. Fig. i is a plan view. Figs. 5 and 6 are views illustrating the switch devices. Fig. 7 is a detail 'view of the resistance-coil. Figs. '7 and 7 are detail views. Figs. 8 and 9 are views illustrating modifications.
ratus, and comprises counterpart platesa a, secured together by means of bolts?) 1 I) I) and c, the latter being insulated from the platesv a by means of an insulating-sleeve 0.
tray being made'in two parts. and provided with perforations for the pa'ssageof the bolts 1), insulating-sleeves cdbeing inserted within said perforations, so'as to insulate the. tray from said bolts b, and at the ends of said sleeves washers c are disposed between the tray and frame, so as to insulate these parts from. each other. The tray B is constructed to receive a resistance-coil 0 between its members, said coil and tray being insulated from (each other by means of suitable insulating resistance material, and between its convolutions insulating material e (such asmica) is placed.
The resistance-c0110 ispreferably provided terial, and said coil is milled across the face to produce a contact-path g, with which a brush, (similar to a commutator-brush, hereinafter described, makes contact. The contact-path g is preferably made in the arc of a circle, extending outwardly from. opposite sides of the non-conducting center or hub f, so as-to accommodate the contactbruslnwhich I prefer to attach to a pivoted .leverD. The leverl) is pivotally connected between its ends with the bolt 0 and insulated therefrom by the sleeve c-. The upper end of the. lover-.1.) is provided with a locking pin having a handle it, said pin. being adapted to normally enter a socket 71- in. a quadrant h", secured to the top of the frame A, so as to retain said lever normally ina vertical position and the con- A represents the main frame of the appa featuresof construction and combinations and Within the frame Aa tray B is located, said material (I. The coilCis preferably composed of ribbon of German silver or other suitable with ahub or centerf, of non-conducting matact-brush in engagement with the hub 01' disk f in the center of the resistance-coil; Stops h are adjustably secured to the quadrant k wherebyto limit the throw of said lever, said stops being serrated or toothed on their under faces to engage similar serrations or teeth 7v" on the quadrant. Below the pivotal connection of the lever D'with the bolt 0 said lever is made with an opening 1}, in which a plate i, of fiber or other insulating material, is inserted, said insulating-plate being made with an elongated slot 11 To the insulating-plate i a metal plate 2' is secured and provided at its upper end with a lug i having a screw-threaded perforation for the reception of the lower end of a rod 2 the upper end of which is electrically connected with the bolt To the inner face of the metal plate 2' a metal bracket 2' is secured by means of bolts 77, said bolts passing through'an elongated slot 2' in said metal plate i whereby to enable said bracket to be adjusted vertically.
To the bracket 1 a small lever j ispivoted, to which the contact-brush E is secured, said brush being maintained in contact with the resistance device by means of a spring j, one
end of which is connected with the leverj, and the other end is secured to a lug projecting from the metal plate In placing the device in the circuit one wire is connected with the bolt 0, and the other wire is connected with the outer extremity of the coiled resistance material.
A rheostat constructed as above described is very cheap, since the cost of winding the ribbons of the spiral conductor and interposed insulation, and finishing the contact-path is very small.
From the construction and arrangement of parts above described it will be seen that when the lever D is turned on its fulcrum in one direction or the other more or less resistance will be included in the circuit, the current passing through the apparatus as indicated by the arrows in Fig. 2.
By the use of my improved construction of rheostat the employment of separate contactplates mounted on an insulated base and connected by wires to the resistance is entirely done away with, and therefore one great source of expense, trouble, and annoyance is eliminated.
A further advantage of my improved construction is that there are from twenty-five to forty contacts per inch, depending upon the thickness of the conductor used, and therefore the number of contacts is so great as to reduce the voltage between the contacts to so small an amount as to entirely eliminate the sparkingwhich takes place in rheostats as they have heretofore been constructed;
It will be noticed that there are two dis tinct paths 011 the resistance-coil for the c011- tact shoe or brush E that is to say, one pat-h when the brush is moved to the right and a similar path when the brush is moved to the left Thus thecuttin g out of resistance is etc struction and operation of which latter will be presently explained.
The lower end of the levei D is provided with a roller is, adapted to enterthe forked 01' bifurcated end of an armor lever F, secured to a rock shaft F, which latter is mounted in the lower portion of the framework-of the apparatus and at its opposite 8 5 end is provided with an armG, having a bifurcated upper end, for a purpose hereinafter explained. r
A plate or base H, of insulating material, is secured to the rear face of the frame A for the reception and, support of ray improved reversing-switch, a description of which will now follow. Brackets Z are secured toithe base II, and to these brackets switclrlevers I I are pivot-' ally connected at points near their lower ends, and adapted, Dealt-their upper ends to engage "contacteplates mm; projecting from contact-blocks mimi'; To the lower end of each switch-lever. a link at is connected, and said links are connected together by means of a bar or bars '01, of non-conducting mate rial, said her or bars being provided with a a pin or pins 0, which enter the bifurcated end of the lever or arm G. The switch-levers I are also adapted to engage the respective ends of a contact-plate o, secured to a contact-block 0 secured to the center of the base H, one of said switch-levers being normally in contact with said contact-plate '0 and the other switch-lever being normally in Contact with oneof the contact-plates m, and by connecting the short arms of the switchlevers by the bar a when the latter is moved longitudinally ,both switch levers will be shifted simultaneously to reverse the current through themotor with which the apparatus is connected. Tothe upper ends of the contact-blocks m" arms 19 are pivotally connected, in the'free ends of which are-rupturing rollers q are-mounted, and to the upper end of the central contact-block 0 arms r are pi votally connected and provided at their free ends with arcing-rollers Each switchlever is provided at its free end with an arcingtip 3, of carbon or similar materiahadapted to engage the arcing-rollers, the latter being normally retained in their normal positions by means of springs 15, secured at one end to the arms in which the rollers are mounted and at their other ends to the contact-blocks. The reversing-switch constructed as above explained is quite similar to reversingswitc'hes as heretofore constructed, except IIO that it is provided ii'ith an additional. fea-' t1ire-viz., arc-rupturing contacts so placed that the circuit will always be made andi broken between these contacts in'preferenceto making and breaking at themain contacts,
the arc-rupturing rollers being so held as to the entire apparatus as above described it will be seen that by operating the lever I) the contact-ln'ush E will be moved over the con.-
tact.-path on the edges of the ribbon of which the resistance-coil is composed, and simultaneously motion will be imparted to the switch levers through the medium of the lever F,
rock-shaft F, lever or arm G, and connect-' lug-barn to shift the said' switch-levers and reverse the current through the motor. The
moment the operating-handle is turned to the right.- the reversing-switch is set in one direction, thus causin g the current to pass through the armature from that direction, and as the lever D is gradually thrown over the resistance will be cutout gradually by the contactbrush i working over the ribbon. As the lover I) is again thrown to the central position the breaking of the circuit is done on the arcing-rollers, thus preventing sparking at the switch contacts. hen the lever D is thrown in the reverse direction, the reversing-switch is also thrown over, causing the current to pass through the motor in the opposite direction, the contact-brush E cutting out the resistance, as before".
My improvements are exceedingly simple in construction, sparking at the various points of electrical contact is reduced to a minimum, the circuit through the motor can be easily and quickly reversed without injury thereto, and the apparatus is effectual in every respect'in the performance of its functions.
Instead of making the contact-path across the face of the coiled resistanceconductor in thearc of a circle for the accommodation of the movement of the contact-bluish when carried by a pivoted lever said contact-path may be made straight across the face of the coil or exactly in line with the diameter thereof, as shown in Fig. 9.
The resistance-coil instead of being made round may be wound in rectangular form, as shown in Fig. 8.
Various oi her slight changes might be made in the details of construction of my invention without departing from the spirit thereof or limiting its scope, and hence I do not wish to limit myself to the precise details of construction herein set forth; but,
lla vin 'l'ul l y described my invention, what l. claim as new, and desire to secure by Letters Patent, is
l. The combination with a frame and a tray secured thereto, of a resistance coil retained. .in position by said tray and having its convolutions insulated from each other, and a contactdevice adapted to be passed trans versely over said convolut-ions, whereby to include more or less of said. resistance coil in an electric circuit, substantially as set forth.
2. The combination with a frame, of a resistance coil supported therein, said resistance coil being composed of a ribbon of resistanoe material, interposed insulating ma-" 'terial between the convolutions of the coil and a center or hub of non-conducting mas terial, and a contact, device ada-ptedvto be passed transversely over the convolutions of said coil in either direction from said vnonconducting center or hub, substantially as set forth. 7
The combinationwith a frame, of a two-, part tray secured thereto, a resistance coil. having insulating material between its convolutions, .held in position by said tray, in-
sulating material between the coil and tray, and a contact device adapted to be passed transversely over the eonvolutions of said resistance coil, substantially as set forth.
4. The combination with a frame and a resistance coil carried .thereby, said resistance coil having insulating material between its convolutions, of a pivoted lever having an elongated opening, an insulating plate hav-.
ing an elongated slot secured in the slot of the lever, a metallic plate secured to said insulated plate, and a contact device carried by said iiietall'ic plate and adapted to pass over said resistance coil, substantially as set forth.
5. The combination with a frame and a resistance coil having insulating material in terposed between its cenvolutions, of a pivoted lever, a metallic plate carried by said pivoted lever and insulated therefrom, a lever pivotally connected with said plate, and brush carried by said lJlVOtGCls lever ma adapted to pass over the convolutions of the resistance coil, and a spring adapted to maintain said brush normally in, contact with the resistance device or coil, substantially as set forth.
6. The combination with a frame and aresistance coil secured therein, said resistance coil having insulating material between its convolutions, of a pivoted lever, a metallic plat-e carried by and insulated from said 1e ver,'a lever pivoted to said adjustable plate,
tween its convolutions, of a bolt or shaft mounted in the frame and insulated therefrom, an operating lever pivotallyconnected with said bolt or shaft and insulated therefrom, a non-conducting plate secured to said operating lever, a metallic plate secured to the honconducting plate, a bar or rod connecting said metallic plate electrically with said bolt or shaft, an adjustable metallic plate secured to the first mentigned metallic plate, a lever pivoted to the adjustable plate, a contact brush secured to said last-men tion ed lever and adapted to engage the resistance coil and over the convolutions thereof, and a spring adapted to maintain said brush in proper relation to said resistance coil, substantially as set forth.
8. The combination with a frame, a resist.- ance coil carried thereby, and a quadrant on said frame provided with a socket, of: apivoted lever, a cont-act brush carried by and .in-
snlated from said pivoted lever, said brush being adapted to engage and pass over the convolutions of the resistance coil, a pin carried by said lever and adapted to enter the socket in said quadrant, and stops adjustably secured to said quadrant to limit the movement ofsaid pivoted lever, substantially as set forth.
9. The combination withaswitch leverand its contact plate, of an arm pivotally connected in electrical relation to said contact plate, a conducting roller carried by said arm, and a spring" adapted to maintain said roller normallv in the path of the switch leve vvhereby'to produce an arc rupturin contact, substantially as set forth.
10; The combination with. a switch lever and a contact plate, said switch lever having; its end provided with material of low conductivity, of a pivoted arm having electrical connection with the contact pla1e,a conduct in roller in the free end of said arm, and a spring constructed and adapted to maintain the roller in the path of the poor conducting" material at the end of the switch lever, substantially as set forth.
ll. The combination witha frame made in two parts secured together, of a tray made in two parts and inclosed by said frame, a-resistance held in said tray, a contact device for the resistance, a reversing switch mounted 011 the frame and an operating device connected with said contact device and, reversing switch, substantially as set forth.
In testimony whereof I have signed, this specification in the presence of two subscribing witnesses.
JONATHAN P. I FTSKE.
\Vitnesses: WILLIS ll. RAMSEY E. WooLGAR.
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US549597A true US549597A (en) | 1895-11-12 |
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Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4528544A (en) * | 1983-09-12 | 1985-07-09 | Allied Corporation | Control apparatus for variable speed reversible motor |
-
0
- US US549597D patent/US549597A/en not_active Expired - Lifetime
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4528544A (en) * | 1983-09-12 | 1985-07-09 | Allied Corporation | Control apparatus for variable speed reversible motor |
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