US3655994A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electric fence charger
Assignee: Wire Sales Co
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Filing: 1971-02-08
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Granted: 1972-04-11
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Expires: 1991-02-08
Abstract
Abstract A device for periodically applying a high potential on an electric fence has means for applying such potential for very short times at periodic intervals. The time between successive charging intervals depends upon whether the fence is ''''loaded'''' (where an animal grounds such fence) or is ''''unloaded''''. If the fence is ''''unloaded'''', the repetition rate of charging pulses is minimized and if the fence is ''''loaded'''', the pulse repetition rate is increased. The change in pulse repetition rate is determined by the fence ''''loading'''' reflected into the fence charger system and determines the discharge level of a timing capacitor.
Inventors
- 👤 Elmer K Malme
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 13:53
CPC Classifications
H; H05; H05C; H05C1/00; H05C1/04
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
391 words
An electric fence charger for intermittently charging a fence to a shocking potential, said charger including a first storage capacitor, means for charging said first storage capacitor to a predetermined high potential within a fraction of a second, a first solid state device having positive, negative and gate electrodes, a wire connection from said negative electrode to a first junction point, a pulse step-up transformer having primary and secondary windings, a direct connection from one terminal of said primary winding to said first junction point, a direct wire connection from the other terminal of said primary winding to the other terminal of said first capacitor, a first resistor network connected between said positive electrode and gate electrode, said first resistor network including a direct current nonconducting barrier device having a predetermined breakdown potential, said first resistor network including a second junction point with said barrier device disposed between said second junction point and said gate electrode, a second (timing) capacitor connected between said two junction points, a second solid state device having positive, negative and gate electrodes, a direct wire connection from said second device negative electrode to said first junction point, a direct current connection between said second device positive electrode and said second junction point, a second resistor network including a rectifier device having a predetermined voltage breakdown value in the conducting direction between the gate and negative electrodes of said second device, a third auxiliary capacitor connected across a portion of said second resistor network, said third capacitor having one terminal connected to said first junction point and having the other terminal connected through a wire connection to the negative terminal of a rectifier, said rectifier having its positive terminal connected to the other terminal of said pulse transformer primary winding, said system having the portions thereof cooperating so that when the pulse transformer secondary winding faces a sufficiently high resistance, the discharge of said first solid state device causes said second solid state to discharge completely said second capacitor whereby recharging said second capacitor requires maximum recharge duration (and consequent minimum pulse repetition rate), said charger, when facing a lower resistance, operating to permit said first solid state device to discharge without discharge of said second solid state device, said second capacitor discharging only partially through said first device and thus increase the pulse and repetition rate.
Claim 2
Dependent Claim
391 words
An electric fence charger for intermittently charging a fence to a shocking potential, said charger including a first storage capacitor, means for charging said first storage capacitor to a predetermined high potential within a fraction of a second, a first solid state device having positive, negative and gate electrodes, a wire connection from said negative electrode to a first junction point, a pulse step-up transformer having primary and secondary windings, a direct connection from one terminal of said primary winding to said first junction point, a direct wire connection from the other terminal of said primary winding to the other terminal of said first capacitor, a first resistor network connected between said positive electrode and gate electrode, said first resistor network including a direct current nonconducting barrier device having a predetermined breakdown potential, said first resistor network including a second junction point with said barrier device disposed between said second junction point and said gate electrode, a second (timing) capacitor connected between said two junction points, a second solid state device having positive, negative and gate electrodes, a direct wire connection from said second device negative electrode to said first junction point, a direct current connection between said second device positive electrode and said second junction point, a second resistor network including a rectifier device having a predetermined voltage breakdown value in the conducting direction between the gate and negative electrodes of said second device, a third auxiliary capacitor connected across a portion of said second resistor network, said third capacitor having one terminal connected to said first junction point and having the other terminal connected through a wire connection to the negative terminal of a rectifier, said rectifier having its positive terminal connected to the other terminal of said pulse transformer primary winding, said system having the portions thereof cooperating so that when the pulse transformer secondary winding faces a sufficiently high resistance, the discharge of said first solid state device causes said second solid state to discharge completely said second capacitor whereby recharging said second capacitor requires maximum recharge duration (and consequent minimum pulse repetition rate), said charger, when facing a lower resistance, operating to permit said first solid state device to discharge without discharge of said second solid state device, said second capacitor discharging only partially through said first device and thus increase the pulse and repetition rate.
Claim 3
Dependent Claim
47 words
The system according to claim 1 wherein said first capacitor and said timing capacitor each have values of over 10 microfarads, said first capacitor being of the non-polarized type, said third cApacitor having a value of a lower order than either of said first or second capacitors.
Claim 4
Dependent Claim
58 words
The system according to claim 2 wherein a choke is connected between the negative terminal of said first named rectifier and the other terminal of said third capacitor, said choke having a value in the millihenry range for reducing the self-inductive pulse from the primary winding of the pulse transformer after shut-off of said first solid state device.
Claim 5
Dependent Claim
58 words
The system according to claim 1 wherein a second rectifier and current limiting resistor are connected across said first solid state device, the polarity of said second rectifier being reverse of said first device, said second rectifier having a sufficiently high breakdown value to protect said first device against reverse potential originating in said pulse transformer primary winding.
Claim 6
Dependent Claim
144 words
The system according to claim 1 wherein said resistance network associated with said second device comprises a current limiting resistor between said first junction point and the positive electrode of said second device, a second current limiting resistor connected between the gate and negative electrodes of said second device, a potentiometer resistor element connected across said third capacitor, said potentiometer resistor having a wiper associated therewith connected through said second trigger barrier device to the gate electrode of said second device, said second barrier trigger device having a predetermined breakdown potential in the direction of current flow from the wiper toward said gate electrode, said first barrier trigger device connected to said gate electrode of said first solid state device having predetermined cut-in and cut-out potentials in the direction of current flow from said first junction point to the gate of said first device.
Claim 7
Dependent Claim
37 words
The system according to claim 5 wherein a choke in the millehenry range is connected between the negative electrode of the first rectifier and the common terminal of said potentiometer resistance and terminal of said third capacitor.
Claim 8
Dependent Claim
83 words
The system according to claim 6 wherein the resistance element of said potentiometer has a sufficiently high value so that said third capacitor, when charged from the operation of the pulse transformer primary winding, will discharge slowly enough so that substantially no change in the potential across the same will occur during the sudden precipitant change in potential conditions in the system incident to the discharge of either of said devices but instead will discharge over the substantial portion of a sawtooth wave.
Claim 9
Dependent Claim
200 words
A fence charger system comprising a sawtooth wave generator including a primary winding of a pulse transformer, said generator also including a resistor for determining a repetition rate for sawtooth wave generation, a timing capacitor connected between two point in said generator, said two points being so disposed as to have potential differences therebetween available for charging said timing capacitor, the level of charge in said timing capacitor having an effect upon the repetition rate of said generator system, said pulse transformer having a secondary winding for connection to a fence and ground and means responsive to the loading on said secondary winding with regard to high resistance corresponding to a normally ''''unloaded'''' fence and lower resistance corresponding to a normally ''''loaded'''' fence for changing the charge level in said timing capacitor and thereby changing the difference in potential between said two points in said generator sufficiently to increase the repetition rate of said sawtooth generator when said pulse transformer secondary winding sees a ''''loaded'''' fence and to decrease substantially the pulse repetition rate when said secondary winding sees an ''''unloaded'''' fence, the pulse repetition rates being sufficiently different so that substantial changes in operating power for the charger occur.
Claim 10
Dependent Claim
200 words
A fence charger system comprising a sawtooth wave generator including a primary winding of a pulse transformer, said generator also including a resistor for determining a repetition rate for sawtooth wave generation, a timing capacitor connected between two point in said generator, said two points being so disposed as to have potential differences therebetween available for charging said timing capacitor, the level of charge in said timing capacitor having an effect upon the repetition rate of said generator system, said pulse transformer having a secondary winding for connection to a fence and ground and means responsive to the loading on said secondary winding with regard to high resistance corresponding to a normally ''''unloaded'''' fence and lower resistance corresponding to a normally ''''loaded'''' fence for changing the charge level in said timing capacitor and thereby changing the difference in potential between said two points in said generator sufficiently to increase the repetition rate of said sawtooth generator when said pulse transformer secondary winding sees a ''''loaded'''' fence and to decrease substantially the pulse repetition rate when said secondary winding sees an ''''unloaded'''' fence, the pulse repetition rates being sufficiently different so that substantial changes in operating power for the charger occur.
References Cited (Backward Citations)
US3392285A
Cited
US3378694A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-04-11 | 1975-10-11 | 1976-04-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-04-11 | 1979-10-11 | 1980-04-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-04-11 | 1983-10-11 | 1984-04-11 | $7700.00 | Window Closed / Lapsed |