US586560A - Sylvania - Google Patents
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- US586560A US586560A US586560DA US586560A US 586560 A US586560 A US 586560A US 586560D A US586560D A US 586560DA US 586560 A US586560 A US 586560A
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- brake
- arch
- cam
- motor
- pendulum
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- 230000001276 controlling effect Effects 0.000 description 24
- 238000004804 winding Methods 0.000 description 10
- 230000000979 retarding Effects 0.000 description 6
- 210000001699 lower leg Anatomy 0.000 description 4
- 238000009877 rendering Methods 0.000 description 4
- 230000000875 corresponding Effects 0.000 description 2
- 230000005484 gravity Effects 0.000 description 2
- 230000036633 rest Effects 0.000 description 2
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Classifications
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R13/00—Arrangements for displaying electric variables or waveforms
Definitions
- the first object of our invention is to provide a retarding device or brake for the driving member of registering-meters such as described in Letters Patent No. 571,032, issued November 10, 1896, wherein an oscillating motor or pendulum is employed to operate a registering mechanism.
- an oscillating motor or pendulum is employed to operate a registering mechanism.
- pendulum In registering-meters of the character referred to the pendulum is liable to swing through too great an angle and strike other parts of the meter mechanism or framework. This action occurs when, for instance, the pressure on the electric light or power circuit rises, and hence more current passes through the motor-winding, thus producing a stronger pull on the pendulum and causing it to swing through a greater angle.
- the motor-winding is connected across the circuit and will actuate the pend ulum continuously regardless of whether or not current is passing through the meter-solenoids, and as the pendulum is adjusted to make a certain number of oscillations per minute when actuating the registering mechanism it will be seen that when no current is passing through the meter the pendulum will be caused to swing through a greater angle because the registering mechanism is not actuated thereby.
- the pendulum strikes any parts of the meter, it will be brought torest suddenly, and the blow will cause the pendulum to swingin the opposite direction with increased speed, and hence increase the number of oscillations per minute, and resulting in a constant hammering of the pendulum while no current is passing through the ampere-ind ioator. If the oscillations of the pendulum are adjusted so as to prevent hammering while the pendulum is doing no work, it may not swing through a sufficient angle to register the full load when it is doing work. Such irregularities in the amplitude of oscillation of the pendu- Serial No: 638,682. (No model.)
- the brake is carried by and acts upon the shaft or hub of the pendu- 6o lum by the engagement of one member of the brake with a rigid stop. lVhile those devices prevent the hammering of the pendulum, they both tend to accelerate the swing of the pendulum. This tendency is avoided in our improved brake, wherein the brake is pivoted to or is mounted or works upon a stationary support and acts upon a movable member of the pendulum or motor or upon a device oscillated thereby.
- the brake is preferably arranged to engage the oscillating member periodically during the latter part of the swing of the oscillating member in one direction and during a period of the first part of the swing in the opposite direction. The period of engagement may be varied to adjust the oscillations of the pendulum or motor or the device oscillated thereby.
- the second object of our invention is to provide a device which will render deadbeat the controlling cam or arch which is adjusted by the ampere-indicator of the meter and at the same time prevent any swing of the arch due to the energizing of the cores of the ampere indicator when the circuit- 0 breaker is in contact.
- Figure 1 is an elevation of the essential parts of the meter, showing the preferred form 9 5 of brake and the device for rendering the controlling cam or arch dead-beat.
- Figs. 2 and 3 are respectively front and side elevations of a modified form of brake;
- Fig. 4 a view illustrating a spring engaging the driv- I00 ing-cam of the oscillating motor and acting as a brake, and
- Fig. 5 is an edge view of the device for rendering the controlling cam or arch of the ampere-meter dead-beat.
- A is the ampereindicator solenoid; B, the core carried by a shaft pivoted at b; C, the pointer of the ampere-indicator, and D the controlling cam or arch, the pointer O and the arch D being also carried by the shaft of the core B.
- the controlling-cam controls the rate of registration.
- the primary wheel of the register or counter is indicated by the dotted circle E.
- a frame F pivoted at f, carries the pawl for driving the wheel E.
- the frame F is actuated by the driving-cam G, which cam is mounted upon a shaft g, upon which shaft is also mounted the pendulum II.
- the pendulum is provided with a core H, which is actuated by the motor-solenoid 11
- an automatic circuit-breaker of the character described in Patent No. 571,032, above referred to is provided to periodically open and close the circuit to the motor-solenoid H but to avoid confusion in the drawings this circuit-breaker is omitted.
- the brake comprises a plate I, which is pivoted at I to the central frame-plate I a weight J, secured to the plate I, a finger K, which rests on a pin 70, projecting from an arm of the f rame-plate I and which finger holds the brake in its normal position, and a springfinger L, which strikes the pin it) when the pendulum is near the end of its stroke in the direction of the arrow.
- the positions of the parts indicate the meter at rest-that is, with no current passing through either the motor-solenoid or the ampere-indicator solenoid. Nhen the circuit is closed to the motor-solenoid, the pendulum will oscillate, but the driving-cam G will not actuate the pawl-frame F, due to the controlling-arch D being at the zero position.
- the brake-surface M When the pendulum swings in the direction of the arrow, (which is the unattracted swing,) the brake-surface M will engage with the drivingcam G at or before the point 00 of the camsurface, and the engagement of the drivingcam with the brake M will continue to the end of the stroke.
- the device shown in Figs. 2 and 3 may be employed.
- This device consists of a brake-shoe M, carried by a shank m,which works through two bearings m, projecting from the frameplate I
- the downward movement of the brake-shoe is limited by the collar m on the shank m, and between this collar and the upper bearingm is a spiral spring m for giving the proper pressure to the brake.
- a simple bladespring M is shown as the brake.
- This spring may be arranged to be always in contact with the driving-cam G or only at intervals, as is the case with the constructions of Figs. 1 and 2. IVith this arrangement of Fig. 4 the spring will act upon the cam G with a gradually-increasing pressure until it reaches the highest point of the cam.
- the friction is due practically to the spring pressure alone, while in the preferred form shown in Fig. 1 the brake acts first by gravity and then by spring-pressure.
- the brake engage the driving-cam at a certain point during its swing in the direction of the arrow, and the brake in Fig. 1 is located so that it will engage the. driving-cam only after the highest point 0c of the cam has passed under the wheel F, or, in other words, the brake is so located that the cam will register the full capacity of the meter before it strikes the brake.
- This device has a knife-edge N, which engages with the concentric arch D to hold the controlling-arch against movement while the circuit to the motor-coil is closed.
- the knifeedge N is carried by an arm n, pivoted at 'n to an extension of the arm upon which the frame F is pivoted.
- the arm n is provided with a foot N, adapted to engage with the upper side of the frame F, and whereby the knife-edge is raised from the arch D.
- the positions of the parts in Fig. 1 represent the relative positions when no current is passing through the ampere-indicator, the knife edge N holding the controlling-arch against movement.
- the cam G oscillates it strikes the wheel F, but the height of this wheel, due to the zero position of the arch D, prevents the cam actuating the counter.
- the cam is enabled to give a sufficient movement to the frame to raise the pin F from the arch I) and the knife-edge N from the arch D, thus releasing the arch D and permitting it to adjust itself in case any current should be flowing through the ampere'indicator. Assuming now that current is flowing through the ampere-indicator and that the controllingarch is moved to a position beyond the zeropoint, the frame F will drop a corresponding distance.
- the frame F will be moved upward until the pin F strikes the arch D, which will be the proper length of movement for the amount of current flowing through the ampere-indicator.
- the frame F will strike the foot N and raise the knife-edge N from the arch D, the proportions of the parts '12, N, and N being such that the knife-edge will be disengaged from the arch D before the pin F strikes the arch D, and hence the controlling'arch is released and is free to adjust itself to the amount of current flowing through the ampere-indicator before the frame reaches the limit of its upward movement.
- ⁇ Vhat we claim is- 1.
- a registering electric meter the combination with a register, of a controlling de vice adjusted by an ampere-indicator for controlling the rate of registration, and a device for periodically holding said controlling device against movement, substantially as set forth.
- a registering electric meter the combination with an oscillating motor for driving a register, of a controlling device adjusted by an ampere-indicator for controlling the rate of registration, a device for holding said controlling device against movement, and means actuated through the oscillations of the motor for periodically releasing said holding device, substantially as set forth.
- a registering electric meter the combination of an oscillating motor, a register, an actuating device driven by said motor to actuate the register, a controlling-arch ad- 3' usted by an ampere-indicator for controlling the rate of registration, a device engaging with said controlling-arch to hold the same against movement, and which device is periodically actuated by the motor to release the controlling-arch, substantially as set forth.
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- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Stopping Of Electric Motors (AREA)
Description
(No Model.)
W. D. MARKS 8: G. R. GREEN.
ELECTRIC METER.
No. 586,560. Patented July 20, 1897.
UNITED STATES PATENT Crrrcn.
TVILLIAM D. MARKS AND GEORGE ROSS GREEN, OF PHILADELPHIA, PENN- SYLVANIA, ASSIGNORS TO THE AMERICAN ELECTRIC METER COMPANY,
OF SAME PLACE.
ELECTRIC METER.
SPECIFICATION forming part of Letters Patent No. 586,560, dated July 20, 1897.
Application filed May 29, 1897.
To a/ZZ 2072,0111, it may concern.-
Be it known that we, WILLIAM D. MARKS and GEORGE ROSS GREEN, citizens of the United States, residing in the city and county of Philadelphia, State of Pennsylvania, have invented certain new and useful Improvem cuts in Electric Meters, of which the following is a specification.
The first object of our invention is to provide a retarding device or brake for the driving member of registering-meters such as described in Letters Patent No. 571,032, issued November 10, 1896, wherein an oscillating motor or pendulum is employed to operate a registering mechanism. In registering-meters of the character referred to the pendulum is liable to swing through too great an angle and strike other parts of the meter mechanism or framework. This action occurs when, for instance, the pressure on the electric light or power circuit rises, and hence more current passes through the motor-winding, thus producing a stronger pull on the pendulum and causing it to swing through a greater angle.
In practice the motor-winding is connected across the circuit and will actuate the pend ulum continuously regardless of whether or not current is passing through the meter-solenoids, and as the pendulum is adjusted to make a certain number of oscillations per minute when actuating the registering mechanism it will be seen that when no current is passing through the meter the pendulum will be caused to swing through a greater angle because the registering mechanism is not actuated thereby.
If the pendulum strikes any parts of the meter, it will be brought torest suddenly, and the blow will cause the pendulum to swingin the opposite direction with increased speed, and hence increase the number of oscillations per minute, and resulting in a constant hammering of the pendulum while no current is passing through the ampere-ind ioator. If the oscillations of the pendulum are adjusted so as to prevent hammering while the pendulum is doing no work, it may not swing through a sufficient angle to register the full load when it is doing work. Such irregularities in the amplitude of oscillation of the pendu- Serial No: 638,682. (No model.)
lum result in an incorrect registration of the registering mechanism per minute, and hence the register or counter Will not show correctly the amount of energy consumed. A device for guarding against this objection is shown in the patent above referred to, and also in Patent No. 571,037, issued November 10,1890.
In both these patents the brake is carried by and acts upon the shaft or hub of the pendu- 6o lum by the engagement of one member of the brake with a rigid stop. lVhile those devices prevent the hammering of the pendulum, they both tend to accelerate the swing of the pendulum. This tendency is avoided in our improved brake, wherein the brake is pivoted to or is mounted or works upon a stationary support and acts upon a movable member of the pendulum or motor or upon a device oscillated thereby. The brake is preferably arranged to engage the oscillating member periodically during the latter part of the swing of the oscillating member in one direction and during a period of the first part of the swing in the opposite direction. The period of engagement may be varied to adjust the oscillations of the pendulum or motor or the device oscillated thereby.
In electric meters of the character referred to we find that our object is best accomplished So by applying the brake to the working surface of the pendulum-cam which drives the register or counter.
The second object of our invention is to provide a device which will render deadbeat the controlling cam or arch which is adjusted by the ampere-indicator of the meter and at the same time prevent any swing of the arch due to the energizing of the cores of the ampere indicator when the circuit- 0 breaker is in contact.
Our invention is illustrated in the accompanying drawings.
Figure 1 is an elevation of the essential parts of the meter, showing the preferred form 9 5 of brake and the device for rendering the controlling cam or arch dead-beat. Figs. 2 and 3 are respectively front and side elevations of a modified form of brake; Fig. 4:, a view illustrating a spring engaging the driv- I00 ing-cam of the oscillating motor and acting as a brake, and Fig. 5 is an edge view of the device for rendering the controlling cam or arch of the ampere-meter dead-beat.
Referring to the drawings, A is the ampereindicator solenoid; B, the core carried by a shaft pivoted at b; C, the pointer of the ampere-indicator, and D the controlling cam or arch, the pointer O and the arch D being also carried by the shaft of the core B. The controlling-cam, as is now well understood, controls the rate of registration. The primary wheel of the register or counter is indicated by the dotted circle E. A frame F, pivoted at f, carries the pawl for driving the wheel E. The frame F is actuated by the driving-cam G, which cam is mounted upon a shaft g, upon which shaft is also mounted the pendulum II. The pendulum is provided with a core H, which is actuated by the motor-solenoid 11 In practice an automatic circuit-breaker of the character described in Patent No. 571,032, above referred to, is provided to periodically open and close the circuit to the motor-solenoid H but to avoid confusion in the drawings this circuit-breaker is omitted.
The brake comprises a plate I, which is pivoted at I to the central frame-plate I a weight J, secured to the plate I, a finger K, which rests on a pin 70, projecting from an arm of the f rame-plate I and which finger holds the brake in its normal position, and a springfinger L, which strikes the pin it) when the pendulum is near the end of its stroke in the direction of the arrow.
The positions of the parts indicate the meter at rest-that is, with no current passing through either the motor-solenoid or the ampere-indicator solenoid. Nhen the circuit is closed to the motor-solenoid, the pendulum will oscillate, but the driving-cam G will not actuate the pawl-frame F, due to the controlling-arch D being at the zero position. When the pendulum swings in the direction of the arrow, (which is the unattracted swing,) the brake-surface M will engage with the drivingcam G at or before the point 00 of the camsurface, and the engagement of the drivingcam with the brake M will continue to the end of the stroke.
Before the highest point of the cam-surface, which is at 01;, approaches the brake-surface M the spring-finger L will have been forced against post it, and thus the cam will be subjected to additional pressure, which gradually increases until the highest point on the cam is in contact with the brake-surface M. The driving-cam is not subjected to increasing pressure beyond the point a" to the end 662, because that portion of the cam G is concentrio with the shaft g. On the swing of the pendulum in the direction opposite to the arrow it is slightly accelerated by the pull of the solenoid H Thus the pendulum is alternately retarded and accelerated and a uniform rate of oscillation of the pendulum is maintained.
Instead of the brake shown in Fig. 1, the device shown in Figs. 2 and 3 may be employed. This device consists of a brake-shoe M, carried by a shank m,which works through two bearings m, projecting from the frameplate I The downward movement of the brake-shoe is limited by the collar m on the shank m, and between this collar and the upper bearingm is a spiral spring m for giving the proper pressure to the brake.
In the form shown in Fig. 4: a simple bladespring M is shown as the brake. This spring may be arranged to be always in contact with the driving-cam G or only at intervals, as is the case with the constructions of Figs. 1 and 2. IVith this arrangement of Fig. 4 the spring will act upon the cam G with a gradually-increasing pressure until it reaches the highest point of the cam.
In the form of brake shown in Figs. 2 and 4 the friction is due practically to the spring pressure alone, while in the preferred form shown in Fig. 1 the brake acts first by gravity and then by spring-pressure. In practice we prefer to have the brake engage the driving-cam at a certain point during its swing in the direction of the arrow, and the brake in Fig. 1 is located so that it will engage the. driving-cam only after the highest point 0c of the cam has passed under the wheel F, or, in other words, the brake is so located that the cam will register the full capacity of the meter before it strikes the brake.
From the foregoing it will be seen that with either form of brake shown the pendulum will not be arrested suddenly, norwill the brake have any tendency to accelerate the swing of the pendulum in the opposite direction, as is the case with the brakes shown in the patents above referred to.
It will be understood that our form of brake may be applied to any form of oscillating or chrono-electric motor without departing from the spirit of our invention, and that its application is not limited to oscillating motors employed in meters, since it is evident that our brake may be equally as well applied to clocks and other apparatus employing oscillating motors or pendulums.
In an application filed by \Villiam D. Marks January 23, 1897, Serial No. 020,312, is described an arrangement for overcoming magnetic and frictional lag in the ampere-indicator by means of an additional winding. When the current through this winding is controlled by the automatic circuit-breaker for the oscillatingmotor coil, a slight oscillation of the controlling-arch is produced, thus overcoming frictional lag. The register of the meter herein described is actuated by a driving-cam during the unattracted swing of the pendulum and the circuit to the motorcoil is closed for a short period during the attracted swing of the pendulum. The closure of the circuit to the motor-coil takes place While the driving-cam G is still in engagement with the wheel F of the frame F, and hence the controlling-arch is free to move, due to the pull of the ampere-indicator coils.
Thus it will be seen that upon the closure of the circuit to the mot0r-coil an additional movement is given to the controlling-arch due to the increased pull on the core B through the additional winding above referred to. This is objectionable for the reason that should the pin F carried by the frame F, strike the arch D while this additional movement is given to the arch the arch is liable to beheld at that point, and upon the next swing of the pendulum in the direction of the arrow the pawl engaging the wheel E will be moved through a greater distance than it should be, for the reason that the increased movement of the controlling-arch permitted the frame F and the wheel F to drop a greater distance, and hence the advancement of the wheel E will be correspondingly increased, although the amount of current flowing through the ampere indicator coils may not have increased. To prevent this action, we provide the device illustrated in Figs. 1 and 5. This device has a knife-edge N, which engages with the concentric arch D to hold the controlling-arch against movement while the circuit to the motor-coil is closed. The knifeedge N is carried by an arm n, pivoted at 'n to an extension of the arm upon which the frame F is pivoted. The arm n is provided with a foot N, adapted to engage with the upper side of the frame F, and whereby the knife-edge is raised from the arch D. The positions of the parts in Fig. 1 represent the relative positions when no current is passing through the ampere-indicator, the knife edge N holding the controlling-arch against movement. As the cam G oscillates it strikes the wheel F, but the height of this wheel, due to the zero position of the arch D, prevents the cam actuating the counter. However, the cam is enabled to give a sufficient movement to the frame to raise the pin F from the arch I) and the knife-edge N from the arch D, thus releasing the arch D and permitting it to adjust itself in case any current should be flowing through the ampere'indicator. Assuming now that current is flowing through the ampere-indicator and that the controllingarch is moved to a position beyond the zeropoint, the frame F will drop a corresponding distance. As the cam G engages the wheel F on the unattracted swing of the pendulum the frame F will be moved upward until the pin F strikes the arch D, which will be the proper length of movement for the amount of current flowing through the ampere-indicator. As the pin F approaches the arch D the frame F will strike the foot N and raise the knife-edge N from the arch D, the proportions of the parts '12, N, and N being such that the knife-edge will be disengaged from the arch D before the pin F strikes the arch D, and hence the controlling'arch is released and is free to adjust itself to the amount of current flowing through the ampere-indicator before the frame reaches the limit of its upward movement. Upon the return swing of the pendulumthat is, in the direction opposite the arrowthe knife-edge N will reen gage the arch D before the circuit to the motor-coil is closed, and the controllingarch will be again held against movement. Thus it will be seen that at a certain period during the unattracted swing of the pendulum the pin F and the knife-edge N are removed from engagement with the arches D and D, respectively, and hence the controlling-arch is free to adjust itself accurately to the amount of current flowing through the ampere-indicator and insure a proper registration by the counter, while at all other times the control1ing-arch is held stationary.
\Vhat we claim is- 1. The combination with an oscillating motor, of a brake carried by a stationary support and engaging periodically with a movable member of the motor, substantially as set forth.
2. The combination with an oscillating motor, of a brake engaging periodically with a movable member of the motor near one end of the swing of the motor and with a graduallyvarying pressure, substantially as set forth.
3. The combination with an oscillating motor, of a gravity-brake periodically engaging the motor, substantially as set forth.
4. The combination with an oscillating motor, of a gravitybrake acting upon a movable member thereof, and means for increasing the pressure of the brake at a certain period, substantially as set forth.
5. The combination with an oscillating motor, of a brake comprising a pivoted body adapted to make contact with a movable member of the motor, and means for holding said brake out of contact with said movable memher during a certain period, substantially as set forth.
6. The combination with an oscillating motor, of a brake comprising a pivoted weighted body adapted to make contact with a movable member of the motor, and means for holding said brake out of contact with said movable member during a certain period, substantially as set forth.
7. The combination with an oscillating motor, of a brake comprising a pivoted body adapted to make contact with a movable member of the motor, means for holding said brake out of contact with said movable member during a certain period, and a spring for increasing the pressure of the brake at a certain period, substantially as set forth.
8. The combination with an oscillating motor, of a brake comprising a pivoted weighted plate, a projection from said plate engaging a stud to hold said brake out of contact with a movable member of the motor during a certain period, and a spring projecting from said plate adapted to strike said stud at a certain period during the engagement of the brake ally retarding the oscillations, substantially as set forth.
10. The combination of an oscillating mo-, tor, a cam oscillated thereby, a device oscillated by said cam, and a brake engaging with said cam for periodically retarding the oseillations, substantially as set forth.
11. In a registering-meter, the combination With an oscillating motor and a counter driven thereby, of a brake carried by a stationary support and engaging periodically With a movable member of the motor, substantially as set forth.
12. In a registering-meter, the combination of an oscillating motor, a cam oscillated thereby, a counter driven bysaid cam, and a brake engaging periodically-With said cam, substantially as set forth.
13. In a registering electric meter, the combination with a register, of a controlling de vice adjusted by an ampere-indicator for controlling the rate of registration, and a device for periodically holding said controlling device against movement, substantially as set forth.
let. In a registering electric meter, the combination with an oscillating motor for driving a register, of a controlling device adjusted by an ampere-indicator for controlling the rate of registration, a device for holding said controlling device against movement, and means actuated through the oscillations of the motor for periodically releasing said holding device, substantially as set forth.
15. In a registering electric meter, the combination of an oscillating motor, a register, an actuating device driven by said motor to actuate the register, a controlling-arch ad- 3' usted by an ampere-indicator for controlling the rate of registration, a device engaging with said controlling-arch to hold the same against movement, and which device is periodically actuated by the motor to release the controlling-arch, substantially as set forth.
This specification signed and witnessed this 26th day of May, 1897.
WM. D. MARKS. GEO. ROSS GREEN.
Witnesses:
JOHN P. l\IOLAUGHLIN, P. H. SCHAEFFER.
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US586560A true US586560A (en) | 1897-07-20 |
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