US1490704A - Pressure-operated cut-out - Google Patents

Description

A'bril .15, 1924;

,E. P. LARSH PRESSURE OPERATED CUT-OUT Filed Jan. 23, 1919 2 Sheets-Sheet 1 E. P. LARSH PRESSURE OPERATED cUT- u'r April 15, 1924. 1,490,704

I Filed Jan 23, 1919 2 Sheets-Sheet 2 Patented Apr. 15, 1924.

T A, T S

insane EVERETT P. LARSH, OF DAYTON, OHIO, ASSIGNOB, BY MESNE ASSIGNMENTS, TO THE EURO PUMP AND MANUFACTURING- COMPANY, OF DAYTON, OHIO, A COBPORATIGN OF OHIO.

PRESSUBE-QPERATE-D CUT-OUT.

Application filed January 23, 1919. Serial No. 272,723.

To all whom it in my concern Be it known that I, EVERETT P. LAnsH, a citizen of the United States, residing at Dayton, in the county of Montgomery and State of Ohio, have invented certain new and useful Improvements in Pressure-Operated Cut-Outs, of which the followingis a specification.

My invention relates to improvements in quick acting reversing or cut-out mechanism, adapted to open and close an electric switch or valve, reverse a clutch or perform other analogous operations under the influence of variations of pressure, temperature or intensity of actuating medium.

The mechanism forming the subject matter hereof is applicable in the same manner and for the same purposes as that disclosed in my Patent No. 1,248,505, issued Decemher 4th 1917, to which reference is to be had for various methods of applying the actuating power and the mode of employing the mechanism for performance of various operations.

The object of the invention is to simplify the structure as well as the means and mode of operation of such devices, whereby they are not only cheapened in construction but will be more efficient in use, positive in operation, sensitive, and unlikely to get out of repair.

A further object is to provide a quick acting means for positively imparting to the operated element a full stroke movement at each operation.

In view of the fact that such mechanism shows a tendency to waiver or fluctuate as the tripping point is approached, causing a release of holding pressur and consequent arcing of an electric switch or leakage of a valve, prior to the full strokereversal of said part, a further object is to provide a suitable locking means for the operated element which will be released only by the reversing movement.

A further object of the invention is to provide an automatic indicator for indicating the approach of the mechanism to tripping condition, and the variations of the actuating pressure.

' dicator.

With the above primary and other incidental objects in view as will more fully appear in the specification, the invention con sists of the features of construction, the parts and combinations thereof, and the mode of operation, or their equivalents, as hereinafter described and set forth in the claims.

In the drawings, Fig. 1 is a sectional view of the assembled apparatus as it approaches the high pressure tripping point. Fig. 2 is a detail view showing the operative parts in their operated or tripped positions after having reached the high pressure stage. Fig. 3 is a detail perspective view of the reversing levers and the lock therefor. Fig. 4 is a top plan view of the assembled apparatus, showing the relation of the several parts. Fig. 5 is a side elevation illustrating the in- Fig. 6 is a detail sectional view illustrating the indicator connections.

Like parts are indicated by similar characters of reference throughout the several views.

lVhile the apparatus has been shown in the drawing as controlling the opening and closing of an electric switch, it is to be understood that it is not limited to such use, but may be applied to other analogous uses as indicated in my prior patent referred to. Likewise while the drawings show a fluid pressure operated mechanism it is to be understood that it may be float controlled, or actuated by either the flexing or the expansion of a thermostatic member as also described and shown I in said prior patent. Such actuated and actuating members fornr ing no partof the present invention per se, but being fully disclosed in the prior patent aforementioned, of the disclosure of which the present invention is an improvement and amplification, they will not be herein illustrated.

The term cut-out as herein used is to be interpreted as including a switch, valve, clutch or other operated member, while pressure operated is intended to include not only fluid pressure but mechanical pres-- sure or other force by which the reversing levers are oscillated.

In constructing the devirethcre is employed a main frame comprising a hollow or chambered base portion 1 from which project upwardly parallel side plates 22 interconnected by a tie bar 3. The base 1 is preferably formed in separable parts between which is clamped a flexible diaphragm 4. A. passage 7 for fluid under pressure leads to the under side of the diaphragm 4.

Engaged with the diaphragm 4 and moving vertically in unison with the undulations thereof, is a stem or shaft 8 having at its upper end a sliding bearing in a. bushing 9 mounted in a transverse head or bar 10 extending between the side plates 2-2. Adjacent to its lower end the stem or shaft 8 car ies a collar 11 engaged by one end of a helical spring 12, the opposite end of which bears upon the under side of the bushing 9. The spring 12 tends to resist the upward movement of the stem 8 under the influence of fluid pressure upon the diaphragm 4. The tension of the spring 12 and its resistance to the movement of the stem maybe varied by the adjustment of the bushing 9.

Below the collar or head 11 there is formed in the stem 8 a yoke 13 within which engages the short arm of a bell crank 18 pivoted upon a transverse pin 17 mounted in the side plates 2.

The arm of this bell crank is formed with an arcuate head 19 which engages the upper and lower bearing surfaces of the recess of the yoke 13 whereby any vertical movement of the stem 8 under influence of fluctuations of the diaphragm is transmitted to the bell crank 18, oscillating the latter about the fulcrum 17. The long arm of the bell crank is formed with a similar arcuate head 22 engaging in the bifurcation 23 of a second bell crank 24 fulcrumed upon the t'ansverse pin 25. The bifurcation 23 is slightly wider than the head 22 whereby there is permitted a slight degree of lost motion or play. The longer arm of the second bell crank is also bifurcated at 26 and carriesa pin 27 extending across such bifurcation.

Fulcrumed upon a transverse pin 28 supported in the side plates 22 is an oscillatory cut-out arm 29. In the drawing this cutout arm is shown as provided with a pendant integral arm 31 to which the operated element such as the switch, valve, clutch, or other member to be shifted is connected. The cut out arm 29 has been shown as of double form interconnected by a web 30.. The projecting ends of the double arm form a bifurcation across which extends pin 32. This'pin 32 projects laterally beyond the cut-out arm and into a hole 33 of larger diameter in the side plate 2. The engagement of the pin with opposite sides of the hole 33 limits the degree of oscillation of the cut out arm. A similar hole 21 engaged by a pin carried by the bell crank 18 serves to limit the movement of the bell crank to a predetermined range of variation.

As thus far described the construction is quite similar to that set forth in the aforementioned prior patent.

Pivotally connected with each of the transverse pins 27 and 32 carried by the oscillatory members 24 and 29 respectively is a bow spring 34. The ends of the spring nating several parts and reducing the necessary machine and assembly operations, thus materially reducing the costs of construction.

The bow spring is placed under tension by the oscillation of the bell crank 24 toward a position of dead center in relation with the cut out arm 29 upon which the spring 34 exerts a pressure tending to oscillate the cut-out arm about its pivot. the direction of the influence of the spring, i. e. by oscillating the bell crank 24 to and fro beyond the dead center in either direction, the spring is made to act alternately to move the cut-out arm up or down. However means is provided to prevent the movement of the cut-out in one direction until the operating member 24 is well across the dead center, in order that there may be no hesitation of the parts at the moment of reversal. v 7

To this end there is provided a pivoted detent 35, pivoted at 36 to one of the side plates 2 and having a shoulder 37 engaging a flattened extremity of the pin 32 to hold the cut-out arm in depressed position. The detent carries a laterally projecting arm 38 extending into the path of the projecting end of the pin 27 carried by the bell crank 24, whereby said arm is engaged by the projecting end of the pin 27 and oscillated to disengage the pin 32 when the bell crank 24 is well. across the position of dead center. This withdraws the shoulder 37 from the flattened extremity of the pin 32 allowing the cut-out to be thrown to opposite position under the influence of the bow spring 34. The detent is retracted by a spring 35 which is coiled about the pivot of the detent with one end engaging the tie bar 3 and the other end engaged with the detent substantially opposite the shoulder 37. Upon the return movementof the cut-out the detent is pressed back against the tension of the s ring bv the on e 'ement of the extremity 4, v D L) v By changing of the pin 32 with the inclined cam surface immediately above the shoulder 37. When the pin passes the shoulder the detent is immediately thrown to operative position by its spring 35*.

In the drawing the arm 31 has been shown as carrying a block of insulating material to which is attached the transverse electrical contact arm 39 having contact heads 40 to engage with the terminal studs 41 carried by a block of insulating material attached to the main frame.

It will be understood that such electrical connections are for the purpose of illustration and the invention is not limited to such association, but that other devices, such as a valve, clutch shifting means or like elements may be connected to and operated by the cut-out arm.

While the movement of the member 24 or the lever 18 would if closely observed indicate in some degree the variation of the apparatus, the movement of these parts is so short and the lost motion-between the bell crank 18 and the bell crank 24 is such that such indication would be entirely unreliable, and moreover such parts are almost inaccessible for close observation. However, there is provided an oscillatory pointer 42 pivoted at 43 to an auxiliary side plate 44 attached to the side of the main frame. The fulcrum head 45 of the pointer 42 carries a stud or pin 46 projecting inward and engaging beneath the collar 11 of the stem 8.

A retracting spring coiled about the pivot of the pointer with one end engaged beneath a lug on the auxiliary plate 44 and having its other end engaged beneath the stud or pin 46 tends to oscillate the pointer in one direction and to keep the pin 46 in engagement with the collar 11. The pointer is thus actuated in one direction by said spring in unison with the vertical movement of the stem 8, which at all times controls such movement, and is actuated in the opposite direction against the tension of said spring by the reverse movement of the stem 8.

The pointer coacts with a series of graduations 47 upon the main frame to indicate the pressure of the actuating fluid, and the condition of the apparatus in relation with its trip off or operative point.

The apparatus is initially set or operated in one direction by the preponderance of fluid pressure on the underside of the diaphragm 4 which exceeds the tension of the spring 12, and in the opposite direction by the preponderance of the tension of the spring 12 over the fluid pressure beneath the diaphragm.

However the fluid pressure and the spring 12 operate the parts through their initial or setting movement. The cut-out arm 29 is given a quick movement in either direction by the subsequent expansion of the bow spring 34. This is effected by changing the abutment of one end of the bow spring upon the member 24 from a point below the connection of said spring with the cut-out arm to a position thereabove and vice versa. The locking of the cut-out insures a sufficient movement of the member 24 to in turn insure a full stroke of the cut-out. The pointer enables one to determine within certain limits the approximate fluid pressure exerted upon the diaphragm 4 and the approximation of the apparatus to the point of reversal.

From the above description it will be apparent that there is thus provided a device of the character described, possessing the particular features of advantage before enumerated as desirable, but which obviously is susceptible of modification in its form, proportion, detail construction and arrangement of parts, without departing from the principle involved or sacrificing any of its advantages.

While in order to comply with the statute the invention has been described in language more or less specific as to structural features, it is to be understood that the invention is not limited to the specific details shown, but that the means and construction herein described,

comprise but one of several modes of putting the invention into effect, and the invention is therefor claimed in any of its forms or modifications within the legitimate and valid scope of the appended claims.

Having thus described my invention, I claim;

1. The combination of a cut-out member, spring actuated tumbler mechanism for reversing said cut-out member, means for tensioning said tumbler mechanism, detent means for the tumbler mechanism preventing operation thereof, until predetermined tension is obtained, an indicator controlled by said tumbler mechanism and tensioning means for progressively indicating the approach of the tension to the detent release point, substantially as specified.

2. The combination of a cut-out member, and operating mechanism therefor including two relatively movable pivoted levers, an intermediate spring connection between the free ends of said levers, means for oscillating one of said levers past a dead center position to place the spring connection under tension, the retraction of which will actuate the other. lever to effect a movement of the cut-out member, and a lock for the last mentioned lever released by the movement of the first mentioned lever.

3. The combination with a cut-out member and an operating mechanism therefor including two independently movable members relatively movable to and fro past dead center positions, means for actuating one of said members, resilient means placed under tension by the movement of said member, the retraction of which will actuate the second independently movable member, and a lock for said second mentioned independently movable member normally resisting any movement thereof under the influence of said resilient means said lock being disengaged by the first mentioned independently movable member when it has reached a predetermined point in its tensioning move- 10 ment.

In testimony whereof, I have hereunto set my hand this 21st day of November A. D. 1918. 1

EVERETT P. LARSH. Witnesses i JOHN DINEEN, F. L. WALKER.

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