US2617907A

US2617907A - Voltage regulator adjustment

Info

Publication number: US2617907A
Application number: US114621A
Authority: US
Inventors: Umbarger James Andrew; Glenn E Heveran
Original assignee: Reconstruction Finance Corp
Current assignee: Reconstruction Finance Corp
Priority date: 1949-09-08
Filing date: 1949-09-08
Publication date: 1952-11-11
Anticipated expiration: 1969-11-11

Description

J. A. UMBARGER in AL VOLTAGEREGULATOR ADJUSTMENT Filed Sept. 8, 1949 Nov. 11, 1952 INVENTORS:

JAMES A-UMBARGER GLEN E. HEVERAN ATT'Y Patented Nov. 11, 1952 VOLTAGE REGULATOR ADJUSTIVIENT James Andrew Umbarger and Glenn E. Heveran,

Waukegan, IiL, assignors, by mesne assignments, to Reconstruction Finance Corporation, Chicago, 111., a corporation of the United States Application September 8, 1949, Serial No. 114,621

2 Claims.

This invention relates in general to a regulator for controlling an electrical device through an enclosing casing. It is more particularly described as a regulator for controlling the output of an automotive generator.

The ordinary type of controller for an automobile current generator for producing current for recharging the battery comprises a cut out, a current limiter and a voltage regulator, all closely assembled, usually in a more or less convenient place and having a removable cover for encasing and enclosing them against tampering and ordinary manipulation. The most common method of adjusting the regulators heretofore has been to remove the protecting cover and by means of bending tools to alter the tension or position of a spring of the voltage regulator or the current limiter. The act of doing this properly is far more diflicult than it sounds for the reason that it is impossible to tell whether the altered tension of the spring is suflicient or too much. This difficulty is also increased by the fact that the act of replacing the cover usually alters the adjustment made, frequently necessitating several tries before the desired result is obtained. This work frequently must be done by unskilled mechanics and under adverse conditions.

The present invention results from the realization of the need for a simple non-critical means of alterin the current or voltage setting of the regulator without removing the protective cover- An important object of the invention is therefore in the provision of adjusting means attachable to the cover of a regulator and extending through the cover to engage and move an adjustable member within the cover for varying the resistance of a spring or other variable adjusting means.

A further object of the invention is to provide an insulated means extending through a cover for engaging an electrical device within the cover without altering the electrical resistance of any circuits or electrical devices within the cover.

A further object of the invention is to provide an adjusting means extending through a cover adapted to be fixed in position, the adjusting means having a fixed and lockable device engaged by a removable tool so that adjustment is not readily made by unauthorized persons nor is the adjustment likely to become changed or altered except by the application of a proper tool.

Other objects of the invention will appear in the specification and will be apparent from the accompanying drawings in which,

Fig. 1 is a perspective view of the outside of a voltage regulator for an automotive generator which includes an enclosing cover with the adjusting means of the present invention as applied thereto and accessible from the outside;

Fig. 2 is a sectional view showing the cover and the present invention in section and portions of the operating parts of the voltage regulator as enclosed by the casin in elevation, the variable member of this invention engaging the spring contact of the voltage regulator for an automobile generator; and

Fig. 3 is a diagrammatic representation of a regulator to which the present invention is applied for connection to an automotive generator, a storage battery supplied thereby and a current load from the storage battery.

While this invention is particularly described as applied to a voltage regulator for an automobile generator, it may also be utilized in connection with any casing which is preferably fixed to enclose electrical operating parts, but requires adjustment of the parts within the cover. It is particularly applicable to the current regulation of an automotive generator because it is frequently desirable to change the amount of current which is supplied to the storage battery depending for example upon summer or winter driving, and depending somewhat upon the amount of day and night driving of any particular automobile.

Referring now more particularly to the drawings, the electric regulator comprises generally a cut out, a current limiter and a voltage regulator enclosed by a cover l0 applied to a supporting base 12 by fixed fastening means M at the ends thereof. In the top of the cover is an opening it which is covered by a thin plate 18 and firmly fastened to the cover by fastening rivets 20 at the corners thereof. At the inside of the plate and projecting inwardly through the openin l6 within the cover is a flat spring 22 secured by rivets 24 at one end to the plate I8 offset downwardly from the plate intermediate its ends and having an insulating contact member 26 secured at the other end and projecting outwardly therefrom.

To adjust the position of the spring 22 and the engagement of the contact 26, a set screw 28 has a rounded or blunt extremity 30 to engage the upper side of the spring 22 and preferably extends through a lock nut 32 rigidly secured to the plate l8. At the top of the screw is a recessed angular opening 34 adapted to be engaged by a corresponding angular tool 36. The top of the screw is preferably flush with the fixed nut 32 so that the adjusting screw is not easily turned except by a particular tool therefor and the adjusting screw is held firmly in place in any adjusted position.

The voltage regulator within the casing has a fiat spring S (see Fig. 3) fixed at one end and normally closing contacts C at the other end. This spring is opposed by an electro-magnet having an armature VR and a winding coil ER which when energized tends to withdraw the spring S and separate the contacts C. The regulation of this electro-magnet is such that as the regulator is depressed from the cover to engage the spring S, the voltage applied to the battery will be re-- duced and as the pressure of the regulator is reduced by less tension on the spring 22, the voltage applied to the battery will be increased as hereinafter set forth.

The current limiter is represented as having an armature CL with a magnet winding IL for controlling a spring SL which maintains contacts CL normally closed.

The cut out is represented as an electro-responsive device having an armature CO with differential windings EC and 10, the latter attached to one end of a spring S for controlling contacts LO normally open and closed when the winding EC is energized but opened by the winding IC under certain conditions.

The terminals of this regulator are designated as A for the armature, F for the field and B for the battery. A generator G is represented as having an armature connected to ground, a generator field GF connected by a conductor G9 to the terminal F and the other end of the field connected by conductor 2 to the armature terminal A.

A storage battery SB is connected by a conductor M to the regulator terminal B with conductors 36 extending from the battery for the car lights, radio, and the like, and the other side of the battery connected by a conductor 48 to a ground which may be the frame of a car to which the invention is applied. The other terminal of the cut out winding is connected by a conductor 50 to the regulator terminal A. One terminal of the cut out winding EC is connected by a conductor 52 to the armature terminal A, the other terminal being connected to ground. One terminal of the winding ER of the voltage regulator is connected by a conductor 54, to armature terminal A, the other terminal of the winding being connected to ground. One terminal of the current limiter winding IL is connected by conductor 56 with a contact LO of the cut out switch S0 and the other terminal of this'winding is connected by a conductor 58 to the :battery terminal B. p

The current limiter switch SL is connected by a conductor 60 with the field terminal F and one of the contacts CL of the current limiter switch is connected by a conductor 62 with the end of the voltage regulator switch S, one of the terminals C of the switch S being connected by a conductor 64 to ground. The field terminal is also connected by a conductor 65 through a resister 68 to ground.

With this construction, the voltage coil EC of the cut out produces a magnetic pull against the spring SO causing the contacts L0 to close when and if the voltage from the generator becomes sufiiciently great. With these contacts closed, current can flow from the generator armature through the current coil 10 of the cut out, the cut out contacts L0 and the current limiter coil IL through conductor 58 to the storage battery.

With the battery now connected across the generator, the cut out contacts will be electrically locked in closed position by the battery voltage regardless of the electro-motive force of the generator. Except for the effect of the coil IC, a reverse current of destructive magnitude would flow from the battery to the generator during the times when the generator electro-motive force became much less than the battery voltage which would be the case during very low speed operation; Under such conditions, however, the reverse current through the coil 10' opposes the forces caused by the coil EC so that the resultant force will reach zero and release the cut out contacts before the reverse current exceeds a safe magnitude.

This invention does not relates to the out out. The invention does pertain to the current limiter and/or to the voltage regulator although it is shown as applied to the voltage regulator only. In order for current to flow through the generator field winding to the ground, it must pass from the regulator terminal F through the resistor 68 or through the contacts CL of the current limiter and the contact C of the Voltage regulator. With the contacts CL of the current limiter, and the contacts C of thevoltage regulator both closed, nearly all of the field current will flow through these contacts and through conductors 59, E2 and 54 to ground. When either of these contacts open, the field current WillfiOW only throughthe resistor andwill be reduced from its former value. This will cause the generator electro-motive force to be reduced and therefore its output voltage and current will be reduced. 7

When the current output of the generator through the current limiter coil IL becomes large enough to exert sufiicient force on the spring SL to open the contacts CL, the field current will be reduced as explained above until the force exerted rent limiter exerts no influence on the generator 7 under all other conditions which are attended by lesser currents.

Similarly, the output voltage of the generator across the coil ER of the voltage regulator causes a force to work against the spring S opening the contact C, reducing the field current and the generator output voltage until a vibrating and regulating action results, as explained for the current limiter. An important fact is that with both the current limiter and the voltage'regulator, the value of the current or voltage at which the regulation takes place is dependent upon the zesiraiining force on the spring S and the conac Y 7 In the operation of this invention, the ad- 1 justment of the screw 28 changes the tension on the spring 22 and by reducing the effective pressure on the spring, it will more asily respond to the forces caused by the winding coil ER, thereby permitting the regulating action to occur at a lower voltage. V

Backing the screw 28 out, produces the opposlte effect. Obvious the adture would alter its tension for compensating purposes; the spring might be fastened to the regulator strip instead of to the cover. In the latter case, the only part needed in the cover is the contacting screw 28.

Various other constructions may also be adopted for accomplishing the desired result, but the present construction is particularly adapted for us because it may be incorporated with existing voltage regulators without changing any part :of the electrical mechanism of the regulator itself so that the present invention may be considered independent of the actual construction of the regulator mechanism itself so long as it includes a spring element for closing contacts in the current limiter or voltage regulator, the resistance of which is varied by an adjusting means extending through the cover of the regulator. The present invention is therefore independent of the specific electrical regulator construction shown and may be applied to various types of regulameans to vary the spring for different voltages, a.

a cover for completely enclosing the voltage regulating parts, means for attaching the cover in fixed position with respect to the voltage regulator parts, an opening in the top of the cover adjacent the said spring, a plate attachable over the opening to which one end of the spring is connected, the plate having a mounting device extending therethrough, an adjusting element threaded in the mounting device, the inner end of the adjusting element engageable with the sprin intermediate its ends to vary the pressure of the free end thereof and thus to vary the voltage at which it will be attracted for movement by the electro-responsive device, and the outer end of the adjusting element extending to the outside of the plate and to the outside of the mounting device where the element is provided with an angular opening for receiving a tool for rotating the element into and out of engagement with the spring without removing the cover.

2. In combination, a voltage regulator for an electric generator, comprising at least one electro-responsive device which includes a movable contact and a flat spring pivoted at one end and actuated by an electro-magnet for moving the contact at its other end, a cover for enclosing the voltage regulator and the electro-responsive device, the cover having an opening therethrough opposite the said contact moving spring, a plate and means to secure it in closed position over the opemng of the cover, a flat spring secured at one end to the under side of the plate and offset inwardly therefrom, a contact maker at the other end of the last spring to engage the first said spring which holds the movable contact, an ad- Justmg device comprising an element extending through the plate with the inner end in engagement with the spring attached to the plate intermediate the ends of the spring, a mounting device fixed in the plate and extending therethrough 1n which the adjusting device is threaded for ad usting movement, the outer end of the adustmg device being substantially flush with outside of the mounting means and having an angular recess therein for engagement by a tool to adust the pressure upon the spring attached to the plate from the outside of the cover without removing and thereby to vary the pressure upon the contact spring of the voltage regulator.

JAMES ANDREW UMLBARGER. GLENN E. HEVERAN.

REFERENCES CITED The following references are of record file of this patent: m the UNITED STATES PATENTS Number Name Date 300,253 Hazazer June 10, 1884 1,576,768 Loudon Mar. 16, 1926 1,724,197 Hartzell Aug. 13 1929 2,238,383 Collins Apr. 15 1941 2,339,526 Thompson Jan. 18, 1944 2,358,482 Thompson Sept. 19, 1944 2,428,218 Herbst Sept. 30, 1947