US1373474A - Electrical recording or indicating apparatus for boilers - Google Patents

Electrical recording or indicating apparatus for boilers Download PDF

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US1373474A
US1373474A US153610A US15361017A US1373474A US 1373474 A US1373474 A US 1373474A US 153610 A US153610 A US 153610A US 15361017 A US15361017 A US 15361017A US 1373474 A US1373474 A US 1373474A
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contact
tube
contacts
chamber
float
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US153610A
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James M Wight
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United Banking & Savings Co
United Banking & Savings Compa
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United Banking & Savings Compa
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    • GPHYSICS
    • G01MEASURING; TESTING
    • G01FMEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
    • G01F23/00Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm
    • G01F23/30Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm by floats
    • G01F23/56Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm by floats using elements rigidly fixed to, and rectilinearly moving with, the floats as transmission elements
    • G01F23/60Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm by floats using elements rigidly fixed to, and rectilinearly moving with, the floats as transmission elements using electrically actuated indicating means

Definitions

  • This invention relates to electrical recording, indicating and alarm mechanisms for boilers, designed especially for use in the recording ofthe water level of a boiler and for giving a visible and audible indication or alarm when certain high and low levels are reached.
  • this invention is an improvement over the subject mat ter or" my prior Patent No. 1,1793%, granted to me on the 18th day of April, 1916, for water level recorder.
  • the principal object of this invention is to provide in connection with a' float chamber of such recording and alarm mechanism, contact mechanism which eliminates the necessity for grounding one side of the source of current, or for grounding any part of the column itself.
  • the invention in one of its aspects includes the provision of a tube or" good conducting material located in, but wholly 1nsulated from the float/chamber or the extension thereof which incloses the contacts,
  • this tube receiving a movable sliding contact which is actuated by the float, and which is designed to engageinsulated contacts which are connected to the magnets of the recorder proper, or to an alarm or signaling device such as a lamp, bell, or both.
  • Figure 1 is a vertical sectional view through the column or float chamber showing the contact mechanism embodying my invention and the parts inclosing and supporting the same;
  • Fig. 2 is a similar view showlng a modification;
  • Fig. 3 is a transverse sectlonal view substantially along the Fig. 1;
  • Fig. 1 is a side view looking toward the right of Fig. 1, showing the upper part of the structure only;
  • Fig. 5 is a detailsectional view on an enlarged scale showing the sliding contact and the manner 1n which it is connected to the float rod;
  • Fig. 6 is a sectional view on an enlarged scale, showing one of the station ary contacts and the manner in which it is supported and insulated from the surrounding metal parts.
  • 10 represents a float chamber, which at the bottom is designed to be connected by a pipe 11 to the water side of a boiler.
  • the chamber 10 has at its top an extension 12, which at the top is designed to be connected by a pipe 13 to the steam side of a boiler so that the water will at all times stand in the chamber 10 to the level of the water in the boiler.
  • the chamber 10 has suitable openings 14 and 15, to which an ordinary gage glass may be connected, and it has other openings 16, to which trycocks may be connected.
  • the float chamber extension 12 as will be observed from the cross sectional view of Fig.
  • the tube is centered andinsulated from the extension 12, by two rings of insulating material 23 which are preferably of glass, and the tube is held at the desired position in the member 12 by a nut 24, screwed onto the upper end of the tube and resting against the upper glass ring 23.
  • This tube has diametrically'opposite vertical slots 25 and 26, through which extends atransversey vertically movable or sliding contact mem-v ber 27 which, is secured by a set screw 28 to a head 29 atthe upper end ofa rod 30,
  • the movable con.- tact 27 is not insulated from the'head 29,
  • the latter which is electrically connected to the tube 22 by reason of the fact that it has flange-like extensions 32, which slide up and down along the inner surface of the 2 tube 22, is carefully insulated from the rod 30 which supports it.
  • the upper end of the rod is provided with a 'T-head 33 which is re' ceived in a cap 34, screwed on to a boss on the lower end of the head 29, the head 33 being spaced fromthiscap 34 and being separated from the boss on thelower end of the head 29 by insulating material prefend'of this contact being enlarged to form a. contact face or head which engages several insulated contacts in the contact chamber 20.
  • These contacts include a series or" contacts 35, (see particularly Figs. 3 and 4) which in this case extend laterally inward from opposite sides of the plate 21, these contacts Jreferabl extendin inwardl' -alternately from'oneside and then the other, and beingarranged so that the forward face of the enlarged end ofthe movable contact 27 will slide over and thus make electrical connection with'the inner portions of these contacts.
  • These contacts 35 eight of which are here shown, are designed to be connected to the magnets or" a recorder, substantially as shown in my prior patent.
  • high and low water alarm ontacts '36 are provided at the upper and lower ends of the contact chamber 21, these contacts preferably extending in from the front wall of the contact chamber 21, and
  • each contact 35 or 36 has between its ends, within the bushing, a shoulder 39 between which and the inner end of the bushing are disks 40 of mica, the shoulder 39 bein separated from the cap 38 by similar disks-of mica and a glass tube; 41 which'surrounds a portion of the contact, theinner surface of the bushing being lined with mica so that the contact member is very effectively held in position and so insulated from the metal parts surrounding or holding it that there is no likelihood of a ground taking place.
  • the tube 22 is connected to one side of the sourceof current.
  • the connection is made with the tube by means of a contact 43 which is preferably mounted and insulated precisely as are the contacts 35 and 36, the inner end of this contact'43 being in engagement with theiend of the tube, and the outer end being adapted to have an electric conductor attached thereto;
  • the innerend of the contact or conductor 43 is received in an opening formed in the tube, but does not extend beyond the inner surface'of the tube as shown in Fig. 3.
  • the advantage of extending the inner end of the contact or conductor 43 into the wall of the tube is that not only is a good electrical connection obtained between the contact and tube, but the contact- 43 anchors the tube against turning movement in the float chamber extension 12.
  • Fig. 2 I have shown a construction which is adaptedfor high and low water recording or indicating only.
  • the float chamber proper is preciselylike that of the construction first described, and there is mounted on this chamber an exten 'sion constituting a contact chamber 44,
  • the tube 45 is not slotted as is the tube 22, but it receives a dislnlike float actuated contact 46 which is connected to the float rod 30 and engages the inner wall of the tube as the contact is raised or lowered by the float 31.
  • the stationary contacts X tend inwardly through the wall of the tube into the interior thereof, so that they may be engaged by the movable contact 46.
  • I employ only two stationary contacts 47 and 48, the former being the high level contact, and the latter the low level contact.
  • These contacts 47 and 48 are supported and insulated precisely as are the contacts 35, 36 and 43 of the first described construction, but their inner ends project through openings in the tube so that when the movable or sliding contact 46 reaches its upper limit of movement it will engage the high level contact 47, and when it reaches its low limit of movement it engages the low level contact 43.
  • the contact disk 46 is beveled or tapered at its periphery on both i s upper and lower surfaces, and preferably the inner ends of the contacts 47 and 48 have beveled portions which may be formed by screwing beveled nuts 4" and 48 on the inner ends of the conta ts, and which are adapted to receive the beveled peripheral portions of the sliding contact so that when the contact disk 46 engages either contact 47 or 48, it will be pulled firmly against the tube 45. This does away with the necessity of having a close sliding fit between the tube and the contact 46.
  • the contacts 47 and 48 will be connected to one side of a source of current, and to the high and low level recording or signaling device or devices which may consist of magnets, or of lamps or bells, or both, and that the other side of the source of current will be connected to the conductor or contact 49 leading to the tube 45. It will be understood also that when the float actuated sliding contact engages either of the stationary contacts 47 or 48, the circuits will be completed through such contact to the sliding contact 46, then to the tube, and tien to the contact or conductor 49.
  • the conductors leading to and from this apparatus may be connected to the contacts 35, 36, 43, 47, 48 and 49 in any desired manner such as by extending the conductor through an opening in the contact and screwing a nut 50 down on the wire (see Fig. 6).
  • a float chamber including a portion adapted to receive contacts, a conducting tube on the interior of, and extending lengthwise of said portion of the chamber and insu ated therefrom, a float, a movable contact adapted to engage and to be moved lengthwise of said insulated conducting tube, a set of stationary contacts adapted to be successively engaged by said movable contact and normally insulated from the tube, and means for making electrical connection with said tube.
  • a float chamber including a portion adapted to receive contacts, a conducting member on the interior of, and extending lengthwise of said portion of the chamber and insulated there- 3.
  • a float chamber including a portion adapted to receive contacts, a conducting tube on the interior of,

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  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • General Physics & Mathematics (AREA)
  • Level Indicators Using A Float (AREA)

Description

2 SHEETS-SHEET l.
Patented Apr. 5, 1921.
J. M. WIGHT. ELECTRICAL RECORDING 0R INDICATING APPARATUS FOR BOILERS. APPLICATION FILED MAR. 9,1917.
J. M. WIGHT.
ELECTFICAL-RE CORDINGQR INDICATING APPARATUS FOR BOILERS.
APPL |CAT|0N FILED MAR. 9, m7
1 ,373-,4= 74. Patented Apr. 5, 192 1.
2 SHEETSSHEET 2.
* UNITED STATES, PATENT OFFICE.
JAMES M. WIGHT, O F LAKEWOOD, OHIO, ASSIGNOR, BY IVIESNE ASSIGNMENTS, TO THE UNITED BANKING & SAVINGS COIvIPANY, TRUSTEE, OF CLEVELAND, OHIO A 0 PORATION OF OHIO.
ELECTRICAL RECORDING- 0R INDICATING- APPARATUS FOR BOILERS.
Specification of Letters Patent.
Patented Apr. 5', 1921.
Application filed March 9, 1917. Serial No. 153,610.
T 0 all w 720m it may concern:
Be it known that I, JAMES M. WIGHT, a citizen or" the United States, residing at Lakewood, in the county of Cuyahoga and State of Ohio, have invented a certain new and useful Improvement in Electrical Recording or Indicating Apparatus for B011- ers, of which the following is a full, clear, and exact description.
This invention relates to electrical recording, indicating and alarm mechanisms for boilers, designed especially for use in the recording ofthe water level of a boiler and for giving a visible and audible indication or alarm when certain high and low levels are reached. In certain aspects this invention is an improvement over the subject mat ter or" my prior Patent No. 1,1793%, granted to me on the 18th day of April, 1916, for water level recorder.
The principal object of this invention is to provide in connection with a' float chamber of such recording and alarm mechanism, contact mechanism which eliminates the necessity for grounding one side of the source of current, or for grounding any part of the column itself.
The invention in one of its aspects includes the provision of a tube or" good conducting material located in, but wholly 1nsulated from the float/chamber or the extension thereof which incloses the contacts,
this tube receiving a movable sliding contact which is actuated by the float, and which is designed to engageinsulated contacts which are connected to the magnets of the recorder proper, or to an alarm or signaling device such as a lamp, bell, or both. Either the movable contact or the insulated contacts which are engaged by the later, extend through the wall of the tube so thatthe proper electrical contacts and connections are made as he float rises and falls. In either event the construction is such that when the movable contact engages one of the insulated contacts, the connection or circuit is from theinsulated contact so engaged, to the movablecontact, then to the insulated tube and conductor which is connected to the the tube, and to the source of current, such as a battery, lighting circuit, or other source.
The invention may be further briefly summarized as consisting in certain novel details 01": construction and combinations and line 3 -3 of arrangements of parts which. will be descrlbed 1n the specification and set forth in the appended claims.
In the accompanying sheets of wherein I have shown two forms of my invention, Figure 1 is a vertical sectional view through the column or float chamber showing the contact mechanism embodying my invention and the parts inclosing and supporting the same; Fig. 2 is a similar view showlng a modification; Fig. 3 is a transverse sectlonal view substantially along the Fig. 1; Fig. 1 is a side view looking toward the right of Fig. 1, showing the upper part of the structure only; Fig. 5 is a detailsectional view on an enlarged scale showing the sliding contact and the manner 1n which it is connected to the float rod; and Fig. 6 is a sectional view on an enlarged scale, showing one of the station ary contacts and the manner in which it is supported and insulated from the surrounding metal parts.
In the drawings, 10 represents a float chamber, which at the bottom is designed to be connected by a pipe 11 to the water side of a boiler. The chamber 10 has at its top an extension 12, which at the top is designed to be connected by a pipe 13 to the steam side of a boiler so that the water will at all times stand in the chamber 10 to the level of the water in the boiler. The chamber 10 has suitable openings 14 and 15, to which an ordinary gage glass may be connected, and it has other openings 16, to which trycocks may be connected. The float chamber extension 12, as will be observed from the cross sectional view of Fig. 1, includes an upright cylindrical middle portion from which extend outwardly, diametrically opposite slots 17 and 18, the former being closed by a plate 19 which engages flanges 19 and the latter, that is the slot 18, leading or extending into an upright con tact chamser 20 in which contact is designed to be made between certain stationary insulated contacts and the movable contact which is actuated by the float. This contact CllfLDlllJGTdS formed by a slotted plate 21 secured to flanges 21, similar to, but oppositely disposed with reference to the flanges 19 Seated in the cylindrical central portion of the float chamber extension 12 is a tube drawings 22 of brass or other good conducting material which is carefully insulatedfrom the inclosing member or extension 12. In this case the tube is centered andinsulated from the extension 12, by two rings of insulating material 23 which are preferably of glass, and the tube is held at the desired position in the member 12 by a nut 24, screwed onto the upper end of the tube and resting against the upper glass ring 23. This tube has diametrically'opposite vertical slots 25 and 26, through which extends atransversey vertically movable or sliding contact mem-v ber 27 which, is secured by a set screw 28 to a head 29 atthe upper end ofa rod 30,
extending vertically upward from a float 31 in, the float chamber 10. The movable con.- tact 27 is not insulated from the'head 29,
but the latter, which is electrically connected to the tube 22 by reason of the fact that it has flange-like extensions 32, which slide up and down along the inner surface of the 2 tube 22, is carefully insulated from the rod 30 which supports it. For the purposeof insulating the head 29 from the rod 30, and at the same time to provide a good mechanical connection, the upper end of the rod is provided with a 'T-head 33 which is re' ceived in a cap 34, screwed on to a boss on the lower end of the head 29, the head 33 being spaced fromthiscap 34 and being separated from the boss on thelower end of the head 29 by insulating material prefend'of this contact being enlarged to form a. contact face or head which engages several insulated contacts in the contact chamber 20. These contacts include a series or" contacts 35, (see particularly Figs. 3 and 4) which in this case extend laterally inward from opposite sides of the plate 21, these contacts Jreferabl extendin inwardl' -alternately from'oneside and then the other, and beingarranged so that the forward face of the enlarged end ofthe movable contact 27 will slide over and thus make electrical connection with'the inner portions of these contacts. These contacts 35, eight of which are here shown, are designed to be connected to the magnets or" a recorder, substantially as shown in my prior patent.
Additionally, high and low water alarm ontacts '36 are provided at the upper and lower ends of the contact chamber 21, these contacts preferably extending in from the front wall of the contact chamber 21, and
being arranged so that the enlarged end of the movable contact 27 will abutagainst.
them when it reaches respectively its uppermost permissiblemovement and its lowermost permissible movement. 7 v
Each of these contacts 35 and 36 (see Fig.
6) is carefully insulated fromthe walls of the. contact chamber. 21, and in this case each extends through a bushing 3?, threaded into the wall of thecontact chamber andis clamped in position by a cap 38,the contact member 35 or 36 (designated 35 in Fig. 6) being insulated from all metal parts by mica and glass which are clamped between the. innerend of the bushing 37 and the cap 38. In this case, each contact 35 or 36 has between its ends, within the bushing, a shoulder 39 between which and the inner end of the bushing are disks 40 of mica, the shoulder 39 bein separated from the cap 38 by similar disks-of mica and a glass tube; 41 which'surrounds a portion of the contact, theinner surface of the bushing being lined with mica so that the contact member is very effectively held in position and so insulated from the metal parts surrounding or holding it that there is no likelihood of a ground taking place. V 7
As before stated, the tube 22 is connected to one side of the sourceof current. The connectionis made with the tube by means of a contact 43 which is preferably mounted and insulated precisely as are the contacts 35 and 36, the inner end of this contact'43 being in engagement with theiend of the tube, and the outer end being adapted to have an electric conductor attached thereto; Preferably the innerend of the contact or conductor 43 is received in an opening formed in the tube, but does not extend beyond the inner surface'of the tube as shown in Fig. 3. The advantage of extending the inner end of the contact or conductor 43 into the wall of the tube is that not only is a good electrical connection obtained between the contact and tube, but the contact- 43 anchors the tube against turning movement in the float chamber extension 12.
Withthis constructionthe circuit is completed through the sliding contact andthie stationary contacts which the former engages wlthout grounding one side of the chamber including the chamber exte-nsion 12,
In Fig. 2 I have shown a construction which is adaptedfor high and low water recording or indicating only. In this case the float chamber proper is preciselylike that of the construction first described, and there is mounted on this chamber an exten 'sion constituting a contact chamber 44,
circuit or grounding any part of the float chamber, and the upper flange being secured to a flanged cap similar to that shown insulated from the metal walls surrounding it. In this case the tube 45 is not slotted as is the tube 22, but it receives a dislnlike float actuated contact 46 which is connected to the float rod 30 and engages the inner wall of the tube as the contact is raised or lowered by the float 31. Instead of the movable contact 46 extending through the wall of the tube, the stationary contacts X tend inwardly through the wall of the tube into the interior thereof, so that they may be engaged by the movable contact 46. In this instance I employ only two stationary contacts 47 and 48, the former being the high level contact, and the latter the low level contact. These contacts 47 and 48 are supported and insulated precisely as are the contacts 35, 36 and 43 of the first described construction, but their inner ends project through openings in the tube so that when the movable or sliding contact 46 reaches its upper limit of movement it will engage the high level contact 47, and when it reaches its low limit of movement it engages the low level contact 43. Preferably the contact disk 46 is beveled or tapered at its periphery on both i s upper and lower surfaces, and preferably the inner ends of the contacts 47 and 48 have beveled portions which may be formed by screwing beveled nuts 4" and 48 on the inner ends of the conta ts, and which are adapted to receive the beveled peripheral portions of the sliding contact so that when the contact disk 46 engages either contact 47 or 48, it will be pulled firmly against the tube 45. This does away with the necessity of having a close sliding fit between the tube and the contact 46.
Electrical connection is made from the outside of the column 44 to the tube by means of a contact or conductor 49, which is supported and mounted precisely as are the other stationary contacts including the contact or conductor 43 of the first described construction, this contact being here shown as having its inner end enterin an openin in the tube so that it will not only make gooc electrical connection with the tube, but will prevent the tube turning in the column 44.
It will be understood that in use, the contacts 47 and 48 will be connected to one side of a source of current, and to the high and low level recording or signaling device or devices which may consist of magnets, or of lamps or bells, or both, and that the other side of the source of current will be connected to the conductor or contact 49 leading to the tube 45. It will be understood also that when the float actuated sliding contact engages either of the stationary contacts 47 or 48, the circuits will be completed through such contact to the sliding contact 46, then to the tube, and tien to the contact or conductor 49. The conductors leading to and from this apparatus may be connected to the contacts 35, 36, 43, 47, 48 and 49 in any desired manner such as by extending the conductor through an opening in the contact and screwing a nut 50 down on the wire (see Fig. 6).
With both of the described constructions there is avoided the necessity of grounding the circuit or of connecting it to the outer inclosing walls or" the float chamber including the extensions 12 and 44. .At the same time, the desired electrical connections are obtained eflfectively, without danger of grounding or short circuiting, so that an electrical recorder, such for example, as shown in my prior patent and high and low level indicating or alarm devices will be actuated through the engagement of the float actuated contact with the stationary contacts.
The two constructions described, wherein the float actuated contact in one instance extends through the wall of the tube, and wherein the stationary contacts in the other instance extend through the wall of the tube, are illustrative of the fact that my invention in its broad aspects may be modified considerably. Not only may my invention be embodied in either of the forms here shown, but the form or embodiment thereof may be changed in other respects such as in the details of construction, including the arrangement and manner of supporting and insulating the several contact members. I therefore aim in my claims to cover all changes and modifications which do not involve a departure from the spirit and scope of my invention.
Having thus described my invention, what I claim is:
1. In a water level recording or indicating apparatus for boilers, a float chamber including a portion adapted to receive contacts, a conducting tube on the interior of, and extending lengthwise of said portion of the chamber and insu ated therefrom, a float, a movable contact adapted to engage and to be moved lengthwise of said insulated conducting tube, a set of stationary contacts adapted to be successively engaged by said movable contact and normally insulated from the tube, and means for making electrical connection with said tube.
2. In a water level recording or indicating apparatus for boilers, a float chamber including a portion adapted to receive contacts, a conducting member on the interior of, and extending lengthwise of said portion of the chamber and insulated there- 3. In a Water level recording or indicating apparatus for boilers, a float chamber including a portion adapted to receive contacts, a conducting tube on the interior of,
andextending lengthwise of said portion of the chamber and insulatedtl1erefrom,'a movable Vcontact adapted to be engaged and to be moved lengthwiserof said insulated conducting tube, a stationary contact adapted to be engaged by said movable'contact, one of said contacts extending through the Wall of the tube, and means for making an electrical connection With Said tube. 1 r
In testimony-whereof, I hereunto afiix my signature.
JAMES M. WIGHT.
US153610A 1917-03-09 1917-03-09 Electrical recording or indicating apparatus for boilers Expired - Lifetime US1373474A (en)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3118304A (en) * 1964-01-21 Brake system
FR2200510A1 (en) * 1972-09-15 1974-04-19 Bendix Gmbh

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3118304A (en) * 1964-01-21 Brake system
FR2200510A1 (en) * 1972-09-15 1974-04-19 Bendix Gmbh

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