US1985659A - Control device - Google Patents

Description

Dec. 25,- 1934. v w. L. HlcKsTElN Er AL 1,985,659

CONTROL DEVICE Filed Deo. 12, 1930 fz /j //zz 27 WZ, a

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Patented Dec.4 25, 1934 UNITED sTAEs PATEN GCNTRTL DEWCE William L. ckstein, Hrvington, and Edwin CU.,

Loesser, Glen Ridge, N. d.

26 Claims.

This invention relates to control devices which may govern mechanism o1 any type. 1n the particular embodiment we have illustrated the invention is applied to an oil burning steam heater 5 as our rst commercial devices were used in con- 4 tion is to provide a. device that will operate in some :fashion entirely automatically and in respense to either of two movements substantially at right angles to each other or to the combined movements. the present invention is the provision o an automatic switch which will be operated by a horizontal movement of the control device to open or close the switch and in addition will be operated to open or close the device independently of the rst movement if the control rod be moved in a different direction.

A still further object of the present invention lies in the provision of an automatic device for control of the motor of an oil burner by either change in pressure or change in water level or both.

In many installations it is common to cut off the heat when the steam pressure or the temperature reaches some chosen maximum point and to turn on the heat either by moving a valve or starting a. motor when some chosen minimum is reached and the. installation generally contains in addition a separate switch which closes the valve or stops the motor Whenever the water level sinks below a certain chosen point. While the two devices Working together are very common there is no simple compact automatic control unit for accomplishing both purposes.

In the drawing:

Figure 1 is a side elevation partly broken away.

Figure 2 is an end view of the preferred apparatus as shown in Figure 1 but with the ca removed.

Figure 3 is a side elevation of a modied form.

Figure 4 is a still further modification.

Figure 5 is an end view of the switch cradle.

Figure 6 is a plan of the contact members shown in Figure d.

in. the preferred form shown in Figures l and 2, the device consists in a casting lo having a steamy A second and important object of j iT [l .Y 1 i. Application necesite@ le, ieee. seein ne. coince niet *i "u i 1 (Cle 2Min-Stell inlet nipple il and a water inlet 12, the former in communication with the steam chamber of the boiler and the latter in communication with the water which. is being heated. The pressure in the chamber i3 will, therefore, be the same as the pressure in the steam line and the entire device is so located that the chosen water level is at the longitudinal center line ci the cylindrical castlli.

To the open end ci" the casting l is secured a dish lei permanently carrying a corrugated metal cylinder l hereinafter called the bellows. The circular end i6 of the bellows is preferably oi slightly heavier metal than the corrugated portion and this dislf. carries centrally a bearing and carries near its periphery a float 18. While obviously the `doat 18 may be spaced away from the bellows as in earlier models, We iind it convenient 'to build the bellows in the short test tube icrm lustrated and to fasten it securely and permanently to the bellows and also the rod 20 which slides freely but rather snugly 'thru the bearing l?.

From the .above it will be seen that the chamber i3 is uid and liquid tight and that when the steam pressure entering thru port 1l increases the bellows will be made shorter and since the bellows carries the float and the rod 2G is attached to the oat at its far end any increase oi pressure will move the rod 26 in an axial direction and any decrease in pressure, augmented, if desired, by the optional helical spring 2l which we rind unnecessary with the rather low pressure encountered in oil burning heaters, the rod 20 is moved horizontal to the right as seen in Figure l. A further and totally independent movement ot the rod follows changes in the water level. As illustrated the Water level is at the desired height. Should the water level sink in the main device the water level in chamber i3 would respond at once and the float 20 would fall but since the bellows is fast to the-closure disk lli the rod 2O will turn about the bearing 1'? which acts as a ulcrum. The bellows, being readily bendable, will permit the necessary tilting of the end wall lo as will readily be understood by those familiar with these elements. it will thus be seen that the central rod 20 will move axially in response to pressure changes and will tilt about some central point in response to water level changes.

in the preferred form the object which is controlled by movement of the rod is an electric maire and break apparatus of the mercury type known in the trade as a mercoid switch. This tube is given the numeral 22 and receives its currents thru wires 23 leading to ari-outlet box 24. While the tube itself is of well-known commercial form its mounting is novel. lThe removable end wall 14 ol. the pressure chamber carries the outlet box at the bottom and two parallel brackets 25, the free ends of which are con' nected by a pivot rod 26 on which is swung a cradle 27 which is merely a strap of material preferably spring metal to embrace rather iirmly the tiltable mercoid tube 22. At each side and diametrically of the tube is an outwardly Aextending lug 28 positioned so as to be engaged by a rather heavy wire frame 30 adjustably carried on the control rod 20. We prefer to have the engagement between the lug 28 and the frame 30 adjustable because in this way we can use the same device for many differentA types of installation. A very convenient way of .achieving this purpose is by having a portion of the control rodi- 20 threaded and on this threaded portion we locate a nut 31 having an extended sleeve 32 which is annularly grooved to receive the nearly circular end 33 of the fork frame 30. The frame being of spring steel can be adjusted manually after the nut is correctly set so as not to engage either the tube or .the sides of the cradle 27 and preferably the nut 3l should be held in chosen position by some positive means such as the lock nut 34. Upon decrease of pressure in the chamber 13 the rod 20 moves to the right and the space between the lug 28 andthe vertically standing arms of"l the fork 30 increases.

` When, however, the pressure increases within the in the left hand end and the pressure breaks the electric current4 which in this case goes tothe P motor and the stopping of the motor in turn cuts off the supply of liquid fuel. When the pressure or temperature decreases the bellows 15 expands and the current is again completed to the motor.

The same mercury tube 22 responds independently to a change in water level. The control rod 20 at its extreme left hand edge is bent upwardly as at 36. We do not ilnd it necessary to fork this end but the rounded free end strikes the tube at its lowest point and with pressure changes merely slides horizontal on the tube having no eiect whatsoever upon it. Should the water level drop, however, the end 36 of the control rod is elevated and this tilts-the mercury tube 22 in exactly the same way as does the engagement between the frame 30 and the lugs 28. It will be noted that the upturned end 36 of the control rod also acts as a stop for the switch. Except for this provision it would be necessary to have some means for preventing the heavier left hand end of the tube moving downwardly.

In Figure 3 the casing is made in two parts 10u and 10b binding between them in fluid tight manner a circularly corrugated disk 40 to which the control rod 20a is permanently secured. The

oat 18 in this case is spaced from the diafragm disk 40 but the operating mechanism in the left hand space is identical and, as in the preferred form, it is covered by a readily removable light cap 41 which may, if desired, be of anecdote glass or other transparent material. In Figure 4 the mercury switch is replaced by a pair of spaced terminals 44 which are bridged to complete the circuit by the upturned end 36b of the control rod 20h. The frame 30 has its counterpart in a cam surface 45 which presses two spring leaf terminals 44 downward into contact with an electrically-conducting bridging member 46 carried on the control rod preferably in an adjustable manner as by the nut 31h. In this modincation the member 47 moves horizontally in accordance withsome change in conditionsl as,for example, a change in pressure. The rod carries a` plate. 48 which may engage a roller 49 on the control rod which is spring pressed against the plate 48 so as to move the control rod horizontally against the spring. The member' 50 corresponds to the float and it moves vertically in accordance with some change in conditions as, for example, the water level. This member 50 ends in a ring 51 which rather Asnugly embraces the control rod which slides freely in a spherical bearing 52 set in a wall 14". As in the other modifications the circuit is completed or is broken as may be desired upon a movement oi' the member 47 in one direction and by a movement of the member 50 in a vdirection at right angles to the movement of the member 47.

What we claim is:

l. A device operated by changes in water level and pressure, comprising a float, a pressure responsive element secured to said float, means actuated by the float in response to changes in liquid level, said means lsoconnected to the pressure responsive element as to be actuated thereby independently of the liquid level changes.

2. In combination, a float, a pressure responsive device, an operating element, a mercury switch tube and a cradle therefor, said tube and cradle forming a pivoted crank of which the tube is the substantially horizontal arm and the cradle is the substantially vertical arm, said operating element being pivotally supported by the pressure responsivedevice and so connected to the float as tobe actuated by changes in liquid level, the operating element being positioned to move4 against the vertical arm of the suspended crank when actuated by the pressure responsive device, and positioned to move against the horizontal tube when actuated about its pivot by the float.

3. A bellows and a iioat flxedly secured thereto in combination with a rod to produce a movement of one end thereof in two directions normal to each other.

4. A diafragm anda iloat in combination with one end of a rod to produce a movement of the other end of the rod in two directions normal to each other.

5. 'I'he combination with a member to operate a control device, of actuating means to move the member in one direction in accordance with a changed condition, and a second actuating means xedly secured to said first mentioned means to move the member at an angle to such direction in accordance with a different changed condition.

6. In a device for completing an electrical circuit, a rod, a bearing in which the rod' is slidably and pivotally supported, and means located on one side of said bearing moving substantially normally to each other for moving the rod in and about its bearing. f

7. In a pressure operated switch controllin device, a pivoted cradle, a pressure responsive member, a rod connected to said member, a cam adjustably secured on saidrod to tilt the cradle upon increase. of pressure, and means at the end of the rod for holding the cradle at horizontal.

8. In combination, a cylindrical bellows expansible under pressure, a iloat secured to the bellows, and a rod fast to the iloat and passing axially thru the bellows.

9. In combination, a corrugated metal pressure responsive cylinder'closed at one end by a disk, a perforated wall supporting the cylinder at the free end in fluid tight fashion, a rod passing thru the hole in the wall and passing axially thru the cylinder, and a float secured Ito the free end oi the rod.

10. In combination, a chamber adapted to be placed in communication with a iluid reservoir anda pressure system, a. pressure responsive diafragm closing one side of said chamber, a inember pivoted to said diafragm and a float secured to the member and lying within the chamber.

ll. In a switch, a pair of contacts, a bridging member mounted to -ioin said contacts upon lowering of a water level, a second bridging inember, and pressure responsive ineans to cause the second bridging member to loin said contacts.

l2. in combination, a vessel having a steers port and a water port, e. float within said chainber, a pivoted lever carrying said oat, pressure responsive means for moving the pivot ci the lever in a horizontal direction, a tiltable member supported by the lever, and means for translating the sliding movement of the lever into tilting movement of the-member independently ci the support given the tilting member by the rod.

is. in combination, a rod, adapted to open .and close an electric switch, means responsive to pressure changes to move the rod, and d oat secured to said rod to rnove the rod in response to changes in liquid level.

le. An electric switch, a rod, a pressure responsive member secured to said rod to move the rod axially to operate said switch, and a float directly secured to said rod to operate said switch in accordance with liquid level changes.

15. A switch operating unit consisting of means responsive to liquid level changes and means responsive to pressure changes, and a switch engaging member rigidly secured to both of said means to move constantly therewith.

i6. In combination, a member having a free end adapted to be operatively connected to a desired mechanism, activating meanslocated at a ilxed distance from said free end and responsive to liquid level changes for moving the free end ci said member, and means responsive to pressure changes to move the free end of the member, said first mentioned means being so connected to said member as to maintain said xed distance during all changes in pressure and liquid level.

i7. In combination, a chamber having an opening in one wall, a pressure responsive device sealing said chamber, a rod centrally pivoted in said device, a float within the chamber and secured to one end of the rod, the free end of said rod extending thru said opening, a switch adjacent to said free end and adapted to be operated thereby upon movement of the rod by pressure on. the device or by change in water level in sai'i chamber.

i8, A combined pressure and float actuated switch mechanism for boilers, comprising a casing having means for communicating with the interor of a boiler above and belowthe water level thereo, an electric switch mechanism including a mercury tube switch and operating means for throwing the switch tube to open and closed posiiions, an expansible and contractible member within the casing and connectedto said switch operating means whereby a change of pressure in the casing actuates the switch actuating means, in combination with means within the casing including e, float, said switch operating means connected to and communicating the movement of said oat to the exterior oi the casing whereby changes in the water level in the boiler actuate the switch.

i9. in combination, a casing, an apertured closure on one end of the casing, a pressure responsive bellows secured to said closure over said aperture and extending within the casing, a float secured to the inner end of the bellows, a rod connected to the bellows and to the oat and extending thru said aperture and switch means mounted adjacent the free end of the rod whereby movement ci the rod due to pressure change and water level change or both operates said switch.

2li. lin combination, a cylindrical bellows havine e, closed end and an open end, a float sealed to said closed end, a rod secured to said closed end, a water level casing having an apertured wail and ineens for securing said open end to said wail whereby the bellows, the float and the rod are supported by the wall, said rod extending from said closed end axially thru the bellows and thru said wall and means mounted exterior oi said casing adapted to be operated by axial and transverse movement of the free end of said rod.

2l. il device operated by changes in water level and pressure, comprising e, pressure re sponsive element, float supported by said element, ineens actuated by the float in response to changes in liquid level, said means being hxediy secured to the pressure responsive element whereby chmees in pressure actuate said means independently ci change in liquid level.

22. in combination, a water level casing havin@ s. removable apertured lwall, a pressure responsive bellows within the casing secured to the wall, a float secured to the bellows, a rod secured to the doet and thereby to the bellows and extending thru the aperturedV wall, and a switch mounted on said casing adjacent the free end of said rod and adepted to be operated thereby.

23. d combined pressure and oat actuated switch mechanism for boilers, comprising a water level casing, a pressure responsive device and a i'loat within the casing, an electric switch mechanisrn including a mercury switch tube suspended in a pivoted cradle, a unitary means for moving the tube into open and closed positions, said means being connected to the pressure responsive device and doet on the interior of the casing; whereby change in pressure or change in water level will actuate said switch.

24. A combined pressure and float actuated mechanism for boilers, comprising a casing provided with ineans for communicating with the interior of s, boiler above and below the water level thereof, an electric switch mechanism including a mercury switch tube pivotally supported by said casing, unitary operating means for moving the switch tube into open and closed positions, a pressure responsive device of the bellows type secured to the inner wall of the casing and a float within the casing, said float and said device being connected together and to said switch operating means whereby either change in pressure or change in water level or both will move said operating means to actuate said switch.

25. In a. mercury tube switch having Ybut two moving parts, a support, a cradle freely suspended on. a pivot in said support, a mercury tube resilently clamped in said cradle and adapted to hang in a, substantially horizontal position below said pivot, a. pivoted rod, float means on one end of said rod for turning the same about its pivot to bring the free end thereof into engagement with said tube to thereby actuate the switch.

26. In a mercury tube switch, a support, a cradle freely suspended on a pivot said support, a mercury tube resiliently clamped in said resuena cradle and adapted to hang in a substantially horizontal position below said pivot, a pivoted rod, float means on one end of said rod for turning the same about its pivot to bring the free end thereof into engagement with said tubewto thereby actuate the switch, means for moving said rod and its pivot longitudinally, and means on the EDWIN C. LOESSER. ILLIAM L. HICKBTEIN.

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