CA2030030A1 - Hydro-pneumatic level - Google Patents
Hydro-pneumatic levelInfo
- Publication number
- CA2030030A1 CA2030030A1 CA 2030030 CA2030030A CA2030030A1 CA 2030030 A1 CA2030030 A1 CA 2030030A1 CA 2030030 CA2030030 CA 2030030 CA 2030030 A CA2030030 A CA 2030030A CA 2030030 A1 CA2030030 A1 CA 2030030A1
- Authority
- CA
- Canada
- Prior art keywords
- reservoir
- liquid
- pressure
- sensing
- flexible
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01C—MEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY
- G01C5/00—Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels
- G01C5/04—Hydrostatic levelling, i.e. by flexibly interconnected liquid containers at separated points
Landscapes
- Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- General Physics & Mathematics (AREA)
- Radar, Positioning & Navigation (AREA)
- Remote Sensing (AREA)
- Measurement Of Levels Of Liquids Or Fluent Solid Materials (AREA)
- Measuring Fluid Pressure (AREA)
Abstract
ABSTRACT OF THE DISCLOSURE
A vertical-difference measuring instrument comprising a variable-volume reference reservoir and a sensing reservoir interconnected by a flexible hose, a flexible-walled gas container in the sensing reservoir and a pressure gauge connected in fluid communication with the flexible-walled gas container in the sensing reservoir for giving a visible indication of the vertical distance between the reference reservoir and the sensing reservoir.
A vertical-difference measuring instrument comprising a variable-volume reference reservoir and a sensing reservoir interconnected by a flexible hose, a flexible-walled gas container in the sensing reservoir and a pressure gauge connected in fluid communication with the flexible-walled gas container in the sensing reservoir for giving a visible indication of the vertical distance between the reference reservoir and the sensing reservoir.
Description
2~3~3~
BACKGROUND OF THE INVENTION
-The invention relates to instruments for measuring vertical distances and for assuring that various components of a building structure are at the same level or at specified, predetermined differences in level.
In the construction industry, it is often necessary to place a plurality of structures at the same level or at different levels at known and predetermined differences between the various levels. For example, in laying tile, positioning windows vertically, positioning wall panels vertically, and the like, it is necessary that all of the particular components be at exactly the same level or at precisely predetermined level differences.
There are various methods and apparatus used in ascertaining such levels. The conventional spirit level or bubble level may be used, but when large distances between the components are involved, this approach is difficult. In addition, when one starts at a given point on a long wall, particularly a wall with corners, it is possible to accumulate errors as one pro~resses along the wall and end up with a non-level panel, paint line, tile line, or the like.
Most often, these craftsman measure from the floor or some other structure which is presumed, or at least hoped to be level. While this is satisfactory in some instances, it is not reliable in many structures.
The well-known surveyor's transit is unsuited to use by tile layers, plumbers, carpenters and others who work in confined spaces and often alone. These instruments ' -: . -:
:- ... : : -. . . . .. . ...
.
20309~
require, for efficient use, two workmen and are expensive and cumbersome. In addition, one cannot assure that a tile line, for example, which extends into several rooms will be level because these rooms may not be visible from a given site.
S Laser transits are even less suited to applications as described because of their great expense and the great amount of time required to set up the equipment.
There is a great and long-standing need for an inexpensive but accurate measuring and leveling device which will assure that components are exactly level with each other, vertically, or are at exactly predetermined differences in vertical position, as may be desired~in particular instances. It is to a solution of this long-standing problem and meeting this serious need in the building and construction industries that the present invention is directed.
SUMMARY OF THE INVENTION
The present invention is a vertical-difference measuring instrument comprising a variable-volume reference reservoir and a sensing reservoir interconnected by a flexible hose, a flexible-walled gas container in the sensing reservoir and a pressure gauge connected in fluid communication with the flexible-walled gas container in the sensing reservoir for giving a visible indication of the vertical distance between the reference reservoir and the sensing reservoir.
As a leveling instrument for assuring that plural points on vertical surfaces in a building structure are at the same level, the invention comprises two basic structural assemblies. A liquid-containing system comprises a variable-liquid-volume reference reservoir, a `. ' ' ' ' ' ' " ' ' , ' ' ' ,' ' "' ' ' .'' . , , '.
.; ' . ' ~ , " '' '. " ' :' ' ,'. . ' ' ' ' '., ,. ' ' 203Qo3a sensing reservoir, and a flexible conduit having a first end and a second end for connecting said reservoirs in liquid communication with each other. The liquid-containing system also includes means connecting the reference reservoir at the first end of and in fluid communication with the flexible conduit means connecting the sensing reservoir at the second end of and in fluid communication with the flexible conduit, and liquid filling the flexible conduit. The instrument also includes a fluid-pressure gauge having a visible pressure 10 indicator and indicia for giving a visual quantitative -indication of the pressure applied to the gauge. Means are provided for connecting the fluid pressure gaug~e in fluid communication with the sensing reservoir. The fluid-pressure gauge and liquid-containing system are so connected, constructed and configured that the pressure measured by the pressure gauge is proportional to the vertical distance of the sensing reservoir above or below the reference reservoir. The leveling instrument includes indicia on the gauge, including a zero point and indicia indicating pressures above and below the zero point, and means may be provided for adjusting the indicator to the zero point regardless of the actual pressure applied to the pressure gauge. At the zero point, when so adjusted, the sensing reservoir is always at the same vertical elevation, even though moved from one wall to another or one room to another.
In a preferred embodiment, a flexible-walled gas container is positioned in the sensing reservoir, and the pressure gauge is connected in fluid communication with the flexible-walled gas container. In this embodiment, the fluid-pressure gauge, flexible-walled gas container and liquid-containing system are so connected, '',, ' ' ` ' ' .. , :
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constructed and configured that the pressure measured by the pressure gauge is the pressure of the gas in the gas container which is proportional to the vertical distance of the sensing reservoir above or below the reference reservoir.
The invention also serves as a vertical-difference measuring instrument comprising a variable-volume reference reservoir, a sensing reservoir, a flexible hose having one end connected in fluid communication with the reference reservoir and the other end connected in fluid communication with the sensing reservoir, a flèxible-walled gas container in the sensing reservoir, a pressure gauge connected in fluid communication with the flexible-walled gas container in the sensing reservoir, the pressure gauge having a visible indicator, and liquid filling the reference reservoir and hose and that portion of the sensing reservoir not filled by the gas container, the reservoirs, hose, gas container and pressure gauge being so constructed and connected that the pressure gauge gives a visible indication of the pressure in the gas container which is proportional to the vertical diætance between the reference reservoir and the sensing reservoir.
:.
BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 is a side view in cross-section, largely schematic, showing the use of the leveling or measuring instrument of this invention in connection with a -building structure comprising a floor and a wall.
Figure 2 is a schematic view shown in partial cross-æection of the components and the interconnection of the components of this invention.
i.:: , ~ . -: . : -2 ~ 3 ~ 7 Figure 3 is a front view of the housing holding the gauge and the sensing reservoir which is also depicted in Figure 2, Figure 3 being enlarged with respect to Figure 2.
Figure 4 depicts an alternative construction of the sensing reservoir of this invention interconnected with the gauge.
Figure 5 depicts in schematic view a structure for adjusting the visual indicator on the gauge to zero, regardless of the actual pressure being applied to the gauge-~ .
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In the following description, reference will be madeprincipally to the instrument as a leveling device, but as explained above, the instrument serves just as well for measuring different vertical distances. Also, the following description will use particular reference to convenient structural materials and particular structures, it being clearly understood that these are not limiting and that many alternatives to the various structures and embodiments described below may be used without departing from the spirit and scope of the invention.
Referring first to Figure 1 for an understanding of the use and general operation of the invention, the invention is shown in use in a building structure which comprises a floor F and wall W. The invention conveniently comprises a case 10, although that certainly is not a necessary or an important part of the invention. The case 10, in the preferred embodiment, has a variable-volume reference reservoir 13 connected by means of a tube in fluid communication with a hose 20.
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The reference reservoir 13 may be of any convenient construction or configuration; indeed, the reference reservoir 13 may simply be an open reservoir of liquid.
In Figure 2, the reference reservoir is simply a flexible, non-resilient bag which is incompletely filled with liquid. The liquid conveniently used and which will be referred to hereinafter is water, but any liquid may be used. Liquids with a high coefficient of thenmal expansion should be avoided for greatest accuracy.
Liquids should be free of dissolved gases.
In the preferred embodiment, the variable-volume reservoir 12 is an accordian-fluted balloon-like structure, i.e. a resilient container having accordian-like fluted walls for easy expansion. If desired, the bulb may be constrained at its upper level and allowed to expand horizontally in order to maintain a constant level at the top of the reference reservoir;
however, this is not necessary. Since differences are being measured, any absolute errors introduced by changes in vertical height of the reference reservoir are insignificant.
A housing 30 formed of an injection-molded plastic having walls such as indicated at 32 defining an upper chamber 34 and a lower chamber 36 divided by a wall 38 may be used. Actually, however, the size and configuration of the housing is not critical, and any housing may be used. Indeed, it is not necessary to use a housing, but it certainly is a convenient form of the invention.
The housing 30 carries a gauge 40 which, as shown in Figure 3, may have indicia on the gauge and will have a visual indicator of the pressure or force being exerted on the gauge.
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The lower chamber 36 of the housing, in the preferred embodiment of the invention under discussion, constitutes a sensing reservoir. Also, in the preferred embodiment, a flexible-walled air container, such as a fluted balloon, shown at 50, is positioned and is connected by means of a conduit 52 in fluid communication with the pressure gauge 40. The sensing reservoir is connected through a conduit 54 and through the hose or other flexible conduit 20, thereby forming a fluid communication path.
It will also be noted, in reference to Figure 1, that the hose may follow any path, such as over a beam B, without introducing errors in the measurement. This permits placement of the reference reservoir at any desired reference location and movement of the sensing reservoir to any location, with the hose running under or over objects, whether or not the reference reservoir is visible. For example, in health clubs and the like, multiple shower and dressing rooms are often tiled. The instrument of this invention permits the craftsman to assure that a line of tile is perfectly level throughout all rooms, thus avoiding the embarrassing circumstance of having a tile joint which is off-set vertically.
While it is preferable, for economy and accuracy, to provide the flexible-walled container 50 in the sensing reservoir 36, it is not necessary to do so. As shown in Figure 4, the gauge 40 may be in fluid communication directly with the sensing reservoir 36. In either instance, the gauge 40 will measure the liquid head, i.e.
;~ the distance above or below the reference reservoir of the sensing reservoir. Stated differently, the gauge 40 will measure and indicate the weight of the water being .~:, . : . - , supported by the reservoir 36 or the weight of water above the level of the constant-level sensing reservoir 36, if the sensing reservoir is below the reference reservoir.
In some construction operations it may be desirable to establish a "zero" level or reference level and to assure that all similar structures are at exactly that zero level or at some predetermined distance above or below thàt zero level. It is, therefore, desirable to be able to "zero" the gauge regardless of the force or pressure being exerted upon the gauge. Figure 5 depicts a simple mechanism for accomplishing this desired result. The shaft 60, which is connected to the pr~essure measuring device, extends through a wall or face plate 62 upon which the indicia may be formed. The visual indicator 64 is provided with a hub 66 having a hollow, cylindrical aperture therein which slips over the end of the shaft 60. The hub will cause the indicator to turn ; as the shaft turns, but will also permit the hub to turn relative to the shaft, thus permitting the indicator 64 to be moved to the zero position, thereby "zeroing" the gauge. The movement may be accomplished by a shaft 68 connected to a nob 70 on the outside of the gauge, the shaft extending through a glass or other transparent gauge cover 72.
Having described the basic features and structure of the invention, the various components will be discussed in somewhat greater detail. As previously noted, it is not necessary to provide an enclosed reference reservoir;
all that is necessary is that the volume of liquid which may be held by the reservoir is variable. In a convenient embodiment, the reference reservoir is a ~' .
.
'`-,,""~' `,',, ' . '"'' ' "'"' .' '' ,'' , ', :'~ -' . ,. : , ' . ' ' : , ' ' ~: ' ' ',, ~ .' j .: ' , - . . . . ,. ', .
rubber balloon or even a non-resilient plastic or polymeric bag which is held in a tray or container and is incompletely filled, such that additional liquid may flow into and out of the bag. It is important that the liquid in the reference reservoir be able to change in volume with negligible resistance; otherwise, the struature of the reference reservoir is insignificant.
The hose 20 may be of any conventional design. Many such hoses are available from any industrial supply house. A typical garden hose, small-diameter rubber, chlorinated rubber or other polymeric hose, or a high-pressure hose such as is used for filling pneumatic tires and the like may be used, for example.
The housing 30 may be made of metal or any other convenient material. Molded plastics are exceptionally convenient in forming housings of this type. The sensing reservoir 36 may be of any design which will assure that the weight of the water, or water head, is transmitted accurately to the gauge. The weight of the water or water head may be transmitted directly to the gauge, i.e.
the gauge may be in continuous liquid communication with the reference reservoir, as depicted in Figure 4. In the preferred embodiment, however, the weight of the water is transmitted by means of air or gas pressure differential, the gas pressure differential being a function of the expansion or contraction of the flexible-walled gas container 50 in the sensing reservoir. In the preferred embodiment, a balloon-like structure is preferred, but a diaphragm, or any other flexible-walled structure, may be used.
The gauge 40 may be of any convenient construction or mode of operation. The conventional Bourdon tube ,. .
:~
~ 35 _ .. _ .. . . , . - . ; . ., . , . , - .
. . ~ , .
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pressure gauge, the diaphragm-type pressure gauge, etc., may be used. In all such pressure gauges it will be noted that there is a mechanical movement system which responds to differences in pressure which differences are transmitted via any Gf many various mechanical movements to an indicator. The indicator may, as depicted in Figure 3, be a simple needle on the face of a gauge with numerical or other indicia thereupon, or it may be a digital or electronic display, or any other display. For simplicity and accuracy and convenience, the well-known DWYE ~ gauge is highly accurate and is conveniently avàilable through industrial supply houses. DWYE
gauges are conveniently used in connection with the~
present invention. It will also be noted that the movement of the mechanical components of the gauge make the use of the flexible-walled gas container unnecessary, since such movement can be accomplished by liquid filling of the gauge tube or diaphragm chamber, etc. It is difficult, however, to fill some gauge mechanisms fully with the liquid and, therefore, it is more convenient and in many instances more accurate to use a gas transmission mechanism such as the flexible-walled gas container which is in fluid communication with the gauge, rather than connecting the liquid directly to the gauge mechanism.
It is also well known that many gauges have built-in 25 "zeroing" mechanisms which work through clutches, gears, ;
or other mechanisms to allow the calibration of the gauge in setting the indicator at zero. The adjusting mechanism depicted in Figure 5 is provided simply for simplicity to illustrate the principal of operation and not necessarily to indicate a preferred mechanism of operation. Any gauge which can be calibrated may be used.
~. :: : . ~ . . ....... . . . . . .
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203~3i~
Returning to the mode of use, for further discussion, it will now be understood that the invention can be used in connection with a marking pencil or any other marker, to mark a line around a plurality of walls which will be perfectly level, or to mark particular points on walls in different rooms which will be perfectly level and will all be the same vertical distance above the floor or other reference point where the reference reservoir is located. By appropriate marking, the exact vertical location of windows, paint lines, wall boards, and other structures may be determined, and high accuracy and leveling achieved. In some plumbing insulations, it is desirable to maintain a high level of accuracy as to~ -vertical height of various drain pipes and to assure proper sloping of the pipes. This invention may be used by plumbers for accomplishing these results.
In like manner, the invention may be used to position various structures at precisely known elevations that are different one from another. For example, if it is desired to position one window a precisely determined number of inches above another window, the instrument may be zeroed at the lével of one window and then moved to the level of the other window, the level of the other window being determined by the reading on the gauge. The gauge indicia maybe made to read in centimeters, inches, feet, etc. Most conveniently for most structural operations, the gauge will read in inches and in fractions of inches, in English and American construction.
The principal of the invention may be embodied in many structures, and many types of components may be ,~" : ~. - , - - - ............................ ... -.. .. . .
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assembled to accomplish the purpose of the invention without departing from the spirit of the invention. The invention is also embodied in a method of determining relative vertical differences or in assuring that two or more components are at the same level. In carrying out this method, a variable volume reference reservoir is positioned at any desired reference point from which other measurements are to be taken. The reference reservoir is in fluid communication with a sensing reservoir to which a gauge is connected for measuring the difference in vertical elevation of the sensing reservoir from the reference reservoir. The sensing reservoir is then moved to obtain a predetermined reading on the~
gauge, or to a predetermined point at which the gauge is set to read zero. By moving the reference reservoir to different points on a wall or upon different walls, exactly the same vertical elevation may be obtained by positioning the sensing reservoir to obtain a zero reading on the gauge. To obtain a different vertical elevation, the sensing reservoir is positioned to obtain a precisely known different reading on the gauge which positions the sensing reservoir a predetermined distance above or below the reference reservoir.
Many variations of the method of the invention may be accomplished without departing from the spirit and scope of the invention.
INDUSTRIAL APPLICATION
.
This invention is useful in the building trades.
, . . .......... .
:- . : : .. - :
~:: 1 . ,. . ~ '
BACKGROUND OF THE INVENTION
-The invention relates to instruments for measuring vertical distances and for assuring that various components of a building structure are at the same level or at specified, predetermined differences in level.
In the construction industry, it is often necessary to place a plurality of structures at the same level or at different levels at known and predetermined differences between the various levels. For example, in laying tile, positioning windows vertically, positioning wall panels vertically, and the like, it is necessary that all of the particular components be at exactly the same level or at precisely predetermined level differences.
There are various methods and apparatus used in ascertaining such levels. The conventional spirit level or bubble level may be used, but when large distances between the components are involved, this approach is difficult. In addition, when one starts at a given point on a long wall, particularly a wall with corners, it is possible to accumulate errors as one pro~resses along the wall and end up with a non-level panel, paint line, tile line, or the like.
Most often, these craftsman measure from the floor or some other structure which is presumed, or at least hoped to be level. While this is satisfactory in some instances, it is not reliable in many structures.
The well-known surveyor's transit is unsuited to use by tile layers, plumbers, carpenters and others who work in confined spaces and often alone. These instruments ' -: . -:
:- ... : : -. . . . .. . ...
.
20309~
require, for efficient use, two workmen and are expensive and cumbersome. In addition, one cannot assure that a tile line, for example, which extends into several rooms will be level because these rooms may not be visible from a given site.
S Laser transits are even less suited to applications as described because of their great expense and the great amount of time required to set up the equipment.
There is a great and long-standing need for an inexpensive but accurate measuring and leveling device which will assure that components are exactly level with each other, vertically, or are at exactly predetermined differences in vertical position, as may be desired~in particular instances. It is to a solution of this long-standing problem and meeting this serious need in the building and construction industries that the present invention is directed.
SUMMARY OF THE INVENTION
The present invention is a vertical-difference measuring instrument comprising a variable-volume reference reservoir and a sensing reservoir interconnected by a flexible hose, a flexible-walled gas container in the sensing reservoir and a pressure gauge connected in fluid communication with the flexible-walled gas container in the sensing reservoir for giving a visible indication of the vertical distance between the reference reservoir and the sensing reservoir.
As a leveling instrument for assuring that plural points on vertical surfaces in a building structure are at the same level, the invention comprises two basic structural assemblies. A liquid-containing system comprises a variable-liquid-volume reference reservoir, a `. ' ' ' ' ' ' " ' ' , ' ' ' ,' ' "' ' ' .'' . , , '.
.; ' . ' ~ , " '' '. " ' :' ' ,'. . ' ' ' ' '., ,. ' ' 203Qo3a sensing reservoir, and a flexible conduit having a first end and a second end for connecting said reservoirs in liquid communication with each other. The liquid-containing system also includes means connecting the reference reservoir at the first end of and in fluid communication with the flexible conduit means connecting the sensing reservoir at the second end of and in fluid communication with the flexible conduit, and liquid filling the flexible conduit. The instrument also includes a fluid-pressure gauge having a visible pressure 10 indicator and indicia for giving a visual quantitative -indication of the pressure applied to the gauge. Means are provided for connecting the fluid pressure gaug~e in fluid communication with the sensing reservoir. The fluid-pressure gauge and liquid-containing system are so connected, constructed and configured that the pressure measured by the pressure gauge is proportional to the vertical distance of the sensing reservoir above or below the reference reservoir. The leveling instrument includes indicia on the gauge, including a zero point and indicia indicating pressures above and below the zero point, and means may be provided for adjusting the indicator to the zero point regardless of the actual pressure applied to the pressure gauge. At the zero point, when so adjusted, the sensing reservoir is always at the same vertical elevation, even though moved from one wall to another or one room to another.
In a preferred embodiment, a flexible-walled gas container is positioned in the sensing reservoir, and the pressure gauge is connected in fluid communication with the flexible-walled gas container. In this embodiment, the fluid-pressure gauge, flexible-walled gas container and liquid-containing system are so connected, '',, ' ' ` ' ' .. , :
~: . . : . . - : . -`.''.'., ' ' ' :, . ,~'~ `- `' : :
~ - . , .
constructed and configured that the pressure measured by the pressure gauge is the pressure of the gas in the gas container which is proportional to the vertical distance of the sensing reservoir above or below the reference reservoir.
The invention also serves as a vertical-difference measuring instrument comprising a variable-volume reference reservoir, a sensing reservoir, a flexible hose having one end connected in fluid communication with the reference reservoir and the other end connected in fluid communication with the sensing reservoir, a flèxible-walled gas container in the sensing reservoir, a pressure gauge connected in fluid communication with the flexible-walled gas container in the sensing reservoir, the pressure gauge having a visible indicator, and liquid filling the reference reservoir and hose and that portion of the sensing reservoir not filled by the gas container, the reservoirs, hose, gas container and pressure gauge being so constructed and connected that the pressure gauge gives a visible indication of the pressure in the gas container which is proportional to the vertical diætance between the reference reservoir and the sensing reservoir.
:.
BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 is a side view in cross-section, largely schematic, showing the use of the leveling or measuring instrument of this invention in connection with a -building structure comprising a floor and a wall.
Figure 2 is a schematic view shown in partial cross-æection of the components and the interconnection of the components of this invention.
i.:: , ~ . -: . : -2 ~ 3 ~ 7 Figure 3 is a front view of the housing holding the gauge and the sensing reservoir which is also depicted in Figure 2, Figure 3 being enlarged with respect to Figure 2.
Figure 4 depicts an alternative construction of the sensing reservoir of this invention interconnected with the gauge.
Figure 5 depicts in schematic view a structure for adjusting the visual indicator on the gauge to zero, regardless of the actual pressure being applied to the gauge-~ .
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In the following description, reference will be madeprincipally to the instrument as a leveling device, but as explained above, the instrument serves just as well for measuring different vertical distances. Also, the following description will use particular reference to convenient structural materials and particular structures, it being clearly understood that these are not limiting and that many alternatives to the various structures and embodiments described below may be used without departing from the spirit and scope of the invention.
Referring first to Figure 1 for an understanding of the use and general operation of the invention, the invention is shown in use in a building structure which comprises a floor F and wall W. The invention conveniently comprises a case 10, although that certainly is not a necessary or an important part of the invention. The case 10, in the preferred embodiment, has a variable-volume reference reservoir 13 connected by means of a tube in fluid communication with a hose 20.
.
.. . . . :. . . ... . . .. -: - .. ..
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203~
The reference reservoir 13 may be of any convenient construction or configuration; indeed, the reference reservoir 13 may simply be an open reservoir of liquid.
In Figure 2, the reference reservoir is simply a flexible, non-resilient bag which is incompletely filled with liquid. The liquid conveniently used and which will be referred to hereinafter is water, but any liquid may be used. Liquids with a high coefficient of thenmal expansion should be avoided for greatest accuracy.
Liquids should be free of dissolved gases.
In the preferred embodiment, the variable-volume reservoir 12 is an accordian-fluted balloon-like structure, i.e. a resilient container having accordian-like fluted walls for easy expansion. If desired, the bulb may be constrained at its upper level and allowed to expand horizontally in order to maintain a constant level at the top of the reference reservoir;
however, this is not necessary. Since differences are being measured, any absolute errors introduced by changes in vertical height of the reference reservoir are insignificant.
A housing 30 formed of an injection-molded plastic having walls such as indicated at 32 defining an upper chamber 34 and a lower chamber 36 divided by a wall 38 may be used. Actually, however, the size and configuration of the housing is not critical, and any housing may be used. Indeed, it is not necessary to use a housing, but it certainly is a convenient form of the invention.
The housing 30 carries a gauge 40 which, as shown in Figure 3, may have indicia on the gauge and will have a visual indicator of the pressure or force being exerted on the gauge.
~ : : ... .. . .
..... .. . .. .. -3 ~ ~
The lower chamber 36 of the housing, in the preferred embodiment of the invention under discussion, constitutes a sensing reservoir. Also, in the preferred embodiment, a flexible-walled air container, such as a fluted balloon, shown at 50, is positioned and is connected by means of a conduit 52 in fluid communication with the pressure gauge 40. The sensing reservoir is connected through a conduit 54 and through the hose or other flexible conduit 20, thereby forming a fluid communication path.
It will also be noted, in reference to Figure 1, that the hose may follow any path, such as over a beam B, without introducing errors in the measurement. This permits placement of the reference reservoir at any desired reference location and movement of the sensing reservoir to any location, with the hose running under or over objects, whether or not the reference reservoir is visible. For example, in health clubs and the like, multiple shower and dressing rooms are often tiled. The instrument of this invention permits the craftsman to assure that a line of tile is perfectly level throughout all rooms, thus avoiding the embarrassing circumstance of having a tile joint which is off-set vertically.
While it is preferable, for economy and accuracy, to provide the flexible-walled container 50 in the sensing reservoir 36, it is not necessary to do so. As shown in Figure 4, the gauge 40 may be in fluid communication directly with the sensing reservoir 36. In either instance, the gauge 40 will measure the liquid head, i.e.
;~ the distance above or below the reference reservoir of the sensing reservoir. Stated differently, the gauge 40 will measure and indicate the weight of the water being .~:, . : . - , supported by the reservoir 36 or the weight of water above the level of the constant-level sensing reservoir 36, if the sensing reservoir is below the reference reservoir.
In some construction operations it may be desirable to establish a "zero" level or reference level and to assure that all similar structures are at exactly that zero level or at some predetermined distance above or below thàt zero level. It is, therefore, desirable to be able to "zero" the gauge regardless of the force or pressure being exerted upon the gauge. Figure 5 depicts a simple mechanism for accomplishing this desired result. The shaft 60, which is connected to the pr~essure measuring device, extends through a wall or face plate 62 upon which the indicia may be formed. The visual indicator 64 is provided with a hub 66 having a hollow, cylindrical aperture therein which slips over the end of the shaft 60. The hub will cause the indicator to turn ; as the shaft turns, but will also permit the hub to turn relative to the shaft, thus permitting the indicator 64 to be moved to the zero position, thereby "zeroing" the gauge. The movement may be accomplished by a shaft 68 connected to a nob 70 on the outside of the gauge, the shaft extending through a glass or other transparent gauge cover 72.
Having described the basic features and structure of the invention, the various components will be discussed in somewhat greater detail. As previously noted, it is not necessary to provide an enclosed reference reservoir;
all that is necessary is that the volume of liquid which may be held by the reservoir is variable. In a convenient embodiment, the reference reservoir is a ~' .
.
'`-,,""~' `,',, ' . '"'' ' "'"' .' '' ,'' , ', :'~ -' . ,. : , ' . ' ' : , ' ' ~: ' ' ',, ~ .' j .: ' , - . . . . ,. ', .
rubber balloon or even a non-resilient plastic or polymeric bag which is held in a tray or container and is incompletely filled, such that additional liquid may flow into and out of the bag. It is important that the liquid in the reference reservoir be able to change in volume with negligible resistance; otherwise, the struature of the reference reservoir is insignificant.
The hose 20 may be of any conventional design. Many such hoses are available from any industrial supply house. A typical garden hose, small-diameter rubber, chlorinated rubber or other polymeric hose, or a high-pressure hose such as is used for filling pneumatic tires and the like may be used, for example.
The housing 30 may be made of metal or any other convenient material. Molded plastics are exceptionally convenient in forming housings of this type. The sensing reservoir 36 may be of any design which will assure that the weight of the water, or water head, is transmitted accurately to the gauge. The weight of the water or water head may be transmitted directly to the gauge, i.e.
the gauge may be in continuous liquid communication with the reference reservoir, as depicted in Figure 4. In the preferred embodiment, however, the weight of the water is transmitted by means of air or gas pressure differential, the gas pressure differential being a function of the expansion or contraction of the flexible-walled gas container 50 in the sensing reservoir. In the preferred embodiment, a balloon-like structure is preferred, but a diaphragm, or any other flexible-walled structure, may be used.
The gauge 40 may be of any convenient construction or mode of operation. The conventional Bourdon tube ,. .
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~ 35 _ .. _ .. . . , . - . ; . ., . , . , - .
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:., . . : .
.,~': :, :; '--;3~
pressure gauge, the diaphragm-type pressure gauge, etc., may be used. In all such pressure gauges it will be noted that there is a mechanical movement system which responds to differences in pressure which differences are transmitted via any Gf many various mechanical movements to an indicator. The indicator may, as depicted in Figure 3, be a simple needle on the face of a gauge with numerical or other indicia thereupon, or it may be a digital or electronic display, or any other display. For simplicity and accuracy and convenience, the well-known DWYE ~ gauge is highly accurate and is conveniently avàilable through industrial supply houses. DWYE
gauges are conveniently used in connection with the~
present invention. It will also be noted that the movement of the mechanical components of the gauge make the use of the flexible-walled gas container unnecessary, since such movement can be accomplished by liquid filling of the gauge tube or diaphragm chamber, etc. It is difficult, however, to fill some gauge mechanisms fully with the liquid and, therefore, it is more convenient and in many instances more accurate to use a gas transmission mechanism such as the flexible-walled gas container which is in fluid communication with the gauge, rather than connecting the liquid directly to the gauge mechanism.
It is also well known that many gauges have built-in 25 "zeroing" mechanisms which work through clutches, gears, ;
or other mechanisms to allow the calibration of the gauge in setting the indicator at zero. The adjusting mechanism depicted in Figure 5 is provided simply for simplicity to illustrate the principal of operation and not necessarily to indicate a preferred mechanism of operation. Any gauge which can be calibrated may be used.
~. :: : . ~ . . ....... . . . . . .
-:.. :. . . . . .
203~3i~
Returning to the mode of use, for further discussion, it will now be understood that the invention can be used in connection with a marking pencil or any other marker, to mark a line around a plurality of walls which will be perfectly level, or to mark particular points on walls in different rooms which will be perfectly level and will all be the same vertical distance above the floor or other reference point where the reference reservoir is located. By appropriate marking, the exact vertical location of windows, paint lines, wall boards, and other structures may be determined, and high accuracy and leveling achieved. In some plumbing insulations, it is desirable to maintain a high level of accuracy as to~ -vertical height of various drain pipes and to assure proper sloping of the pipes. This invention may be used by plumbers for accomplishing these results.
In like manner, the invention may be used to position various structures at precisely known elevations that are different one from another. For example, if it is desired to position one window a precisely determined number of inches above another window, the instrument may be zeroed at the lével of one window and then moved to the level of the other window, the level of the other window being determined by the reading on the gauge. The gauge indicia maybe made to read in centimeters, inches, feet, etc. Most conveniently for most structural operations, the gauge will read in inches and in fractions of inches, in English and American construction.
The principal of the invention may be embodied in many structures, and many types of components may be ,~" : ~. - , - - - ............................ ... -.. .. . .
::i.. - , . :
. :;. ~ . .: .
203~03~ ~
assembled to accomplish the purpose of the invention without departing from the spirit of the invention. The invention is also embodied in a method of determining relative vertical differences or in assuring that two or more components are at the same level. In carrying out this method, a variable volume reference reservoir is positioned at any desired reference point from which other measurements are to be taken. The reference reservoir is in fluid communication with a sensing reservoir to which a gauge is connected for measuring the difference in vertical elevation of the sensing reservoir from the reference reservoir. The sensing reservoir is then moved to obtain a predetermined reading on the~
gauge, or to a predetermined point at which the gauge is set to read zero. By moving the reference reservoir to different points on a wall or upon different walls, exactly the same vertical elevation may be obtained by positioning the sensing reservoir to obtain a zero reading on the gauge. To obtain a different vertical elevation, the sensing reservoir is positioned to obtain a precisely known different reading on the gauge which positions the sensing reservoir a predetermined distance above or below the reference reservoir.
Many variations of the method of the invention may be accomplished without departing from the spirit and scope of the invention.
INDUSTRIAL APPLICATION
.
This invention is useful in the building trades.
, . . .......... .
:- . : : .. - :
~:: 1 . ,. . ~ '
Claims (16)
1. A leveling instrument for assuring that plural vertical points are at the same level, comprising:
(a) a liquid-containing system which comprises;
(i) a reference reservoir comprising a flexible bag containing liquid partially filling the bag constructed and configured for allowing the liquid to expand with negligible resistance to thereby maintain a substantially constant liquid level;
(ii) a sensing reservoir; and (iii) a flexible conduit having a first end and a second end for connecting said reservoirs in liquid communication with each other;
(iv) means connecting the reference reservoir at the first end of and in fluid communication with the flexible conduit;
(v) means connecting the sensing reservoir at the second end of and in fluid communication with the flexible conduit;
and (vi) liquid filling the flexible conduit and contained in the sensing reservoir;
the reference reservoir and conduit being constructed and configured to define a closed fluid-containing system;
(b) a fluid-pressure gauge having a visible pressure indicator and indicia for giving a visual quantitative indication of the pressure applied to the gauge; and (c) means connecting the fluid-pressure gauge in fluid communication with the sensing reservoir;
the fluid-pressure gauge and liquid-containing system being connected, constructed and configured, whereby the pressure measured by the pressure gauge is proportional to the vertical distance of the sensing reservoir above or below the reference reservoir.
(a) a liquid-containing system which comprises;
(i) a reference reservoir comprising a flexible bag containing liquid partially filling the bag constructed and configured for allowing the liquid to expand with negligible resistance to thereby maintain a substantially constant liquid level;
(ii) a sensing reservoir; and (iii) a flexible conduit having a first end and a second end for connecting said reservoirs in liquid communication with each other;
(iv) means connecting the reference reservoir at the first end of and in fluid communication with the flexible conduit;
(v) means connecting the sensing reservoir at the second end of and in fluid communication with the flexible conduit;
and (vi) liquid filling the flexible conduit and contained in the sensing reservoir;
the reference reservoir and conduit being constructed and configured to define a closed fluid-containing system;
(b) a fluid-pressure gauge having a visible pressure indicator and indicia for giving a visual quantitative indication of the pressure applied to the gauge; and (c) means connecting the fluid-pressure gauge in fluid communication with the sensing reservoir;
the fluid-pressure gauge and liquid-containing system being connected, constructed and configured, whereby the pressure measured by the pressure gauge is proportional to the vertical distance of the sensing reservoir above or below the reference reservoir.
2. The leveling instrument of claim 1 wherein said indicia includes a zero point, indicia indicating pressures above and below said zero point,and means for adjusting the indicator to the zero point regardless of the actual pressure applied to the pressure gauge.
3. A leveling instrument for assuring that plural points on vertical surfaces in a building structure are at the same level, comprising:
(a) a liquid-containing system which comprises:
(i) a variable-liquid-volume reference reservoir comprising a flexible bag containing liquid partially filling the bag constructed and configured to allow the liquid to expand with negligible resistance to thereby maintain a substantially constant liquid level;
(ii) a sensing reservoir; and (iii) a flexible conduit having a first end and a second end for connecting said reservoirs in liquid communication with each other;
(iv) means connecting the reference reservoir at the first end of and in fluid communication with the flexible conduit;
(v) means connecting the sensing reservoir at the second end of and in fluid communication with the flexible conduit;
and (vi) liquid filling the flexible conduit;
(b) a fluid-pressure gauge having a visible pressure indicator and indicia for giving a visual quantitative indication of the pressure applied to the gauge;
(c) a flexible-walled gas container in the sensing reservoir; and (d) means connecting the fluid-pressure gauge in fluid communication with flexible-walled gas container, the fluid-pressure gauge, flexible-walled gas container and liquid-containing system being connected, constructed and configured whereby the pressure measured by the pressure gauge is the pressure of the gas in the gas container which is proportional to the vertical distance of the sensing reservoir above or below the reference reservoir.
(a) a liquid-containing system which comprises:
(i) a variable-liquid-volume reference reservoir comprising a flexible bag containing liquid partially filling the bag constructed and configured to allow the liquid to expand with negligible resistance to thereby maintain a substantially constant liquid level;
(ii) a sensing reservoir; and (iii) a flexible conduit having a first end and a second end for connecting said reservoirs in liquid communication with each other;
(iv) means connecting the reference reservoir at the first end of and in fluid communication with the flexible conduit;
(v) means connecting the sensing reservoir at the second end of and in fluid communication with the flexible conduit;
and (vi) liquid filling the flexible conduit;
(b) a fluid-pressure gauge having a visible pressure indicator and indicia for giving a visual quantitative indication of the pressure applied to the gauge;
(c) a flexible-walled gas container in the sensing reservoir; and (d) means connecting the fluid-pressure gauge in fluid communication with flexible-walled gas container, the fluid-pressure gauge, flexible-walled gas container and liquid-containing system being connected, constructed and configured whereby the pressure measured by the pressure gauge is the pressure of the gas in the gas container which is proportional to the vertical distance of the sensing reservoir above or below the reference reservoir.
4. The leveling instrument of claim 3 wherein said indicia includes a zero point, numerical indicia indicating pressures above and below said zero point, and said gauge comprises means for adjusting the indicator to the zero point regardless of the actual pressure applied to the pressure gauge.
5. A vertical-difference measuring instrument comprising: a reference reservoir comprising a flexible bag containing liquid partially filling the bag constructed and configured to allow the liquid to expand with negligible resistance to thereby maintain a substantially constant liquid level; a sensing reservoir;
a flexible hose having one end connected in fluid communication with the reference reservoir and the other end connected in fluid communication with the sensing reservoir; a pressure gauge connected in fluid communication with the sensing reservoir, the pressure gauge having a visible indicator; and liquid filling the reservoirs and hose; the reservoirs, hose and pressure gauge being so constructed and connected that the pressure gauge gives a visible indication of the vertical distance between the reference reservoir and the sensing reservoir.
a flexible hose having one end connected in fluid communication with the reference reservoir and the other end connected in fluid communication with the sensing reservoir; a pressure gauge connected in fluid communication with the sensing reservoir, the pressure gauge having a visible indicator; and liquid filling the reservoirs and hose; the reservoirs, hose and pressure gauge being so constructed and connected that the pressure gauge gives a visible indication of the vertical distance between the reference reservoir and the sensing reservoir.
6. The vertical-difference measuring instrument of claim 5 wherein said indicia includes a zero point, indicia indicating pressures above and below said zero point, and said gauge comprises means for adjusting the indicator to the zero point regardless of the actual pressure applied to the pressure gauge.
7. A vertical-difference measuring instrument comprising: a variable-volume reference reservoir comprising a flexible bag containing liquid partially filling the bag constructed and configured to allow the liquid to expand with negligible resistance to thereby maintain a substantially constant liquid level; a sensing reservoir; a flexible hose having one end connected in fluid communication with the reference reservoir and the other end connected in fluid communication with the sensing reservoir; a flexible-walled gas container in the sensing reservoir; a pressure gauge connected in fluid communication with the flexible-walled gas container in the sensing reservoir, the pressure gauge having a visible indicator; and liquid filling the reference reservoir and hose and that portion of the sensing reservoir not filled by the gas container; the reservoirs, hose, gas container and pressure gauge being constructed and connected, whereby the pressure gauge gives a visible indication of the pressure in the gas container which is proportional to the vertical distance between the reference reservoir and the sensing reservoir.
8. The vertical-difference measuring instrument of claim 7 wherein said indicia includes a zero point, indicia indicating pressures above and below said zero point, and said gauge comprises means for adjusting the indicator to the zero point regardless of the actual pressure applied to the pressure gauge.
9. A method of assuring that a plurality of points at different locations are at the same vertical level, comprising the steps of: positioning a variable volume reservoir comprising a flexible bag containing only liquid partially filling the bag constructed and configured to allow the liquid to expand with negligible resistance to thereby maintain a substantially constant liquid level at a given site, moving a pressure gauge connected through a liquid conduit system to the variable volume reservoir to each of the respective points which are to be level with one another, and fixing such points vertically such that the pressure gauge at each such point measures the same pressure.
10. A method of fixing a plurality of points at different locations at predetermined vertical levels relative to one another, comprising the steps of:
positioning a variable volume reservoir comprising a flexible bag containing only liquid partially filling the bag constructed and configured to allow the liquid to expand with negligible resistance to thereby maintain a substantially constant liquid level at a given site, moving a pressure gauge connected through a liquid conduit system to the variable volume reservoir to each of the respective points which are to be level with one another, and fixing such points vertically such that the pressure gauge at each of the perspective points measures a predetermined pressure difference.
positioning a variable volume reservoir comprising a flexible bag containing only liquid partially filling the bag constructed and configured to allow the liquid to expand with negligible resistance to thereby maintain a substantially constant liquid level at a given site, moving a pressure gauge connected through a liquid conduit system to the variable volume reservoir to each of the respective points which are to be level with one another, and fixing such points vertically such that the pressure gauge at each of the perspective points measures a predetermined pressure difference.
11. An apparatus for comparing the height of spaced apart locations comprising:
(a) a reference reservoir partially filled with liquid to provide a reference liquid pressure representative of the height of said reference reservoir;
(b) a sensing reservoir partially filled with liquid;
(c) a flexible conduit filled with liquid communicating with said reference reservoir and said sensing reservoir to provide an hydraulic system for the liquid pressure in said sensing reservoir to represent the height differential between said sensing reservoir and said reference reservoir;
(d) means responsive to the liquid pressure in said sensing reservoir for translating the liquid pressure in said sensing reservoir into a gas or air pressure representative of the liquid pressure in said sensing reservoir; and (e) gauge means response to said means for displaying the height differential between said reference reservoir and said sensing reservoir.
(a) a reference reservoir partially filled with liquid to provide a reference liquid pressure representative of the height of said reference reservoir;
(b) a sensing reservoir partially filled with liquid;
(c) a flexible conduit filled with liquid communicating with said reference reservoir and said sensing reservoir to provide an hydraulic system for the liquid pressure in said sensing reservoir to represent the height differential between said sensing reservoir and said reference reservoir;
(d) means responsive to the liquid pressure in said sensing reservoir for translating the liquid pressure in said sensing reservoir into a gas or air pressure representative of the liquid pressure in said sensing reservoir; and (e) gauge means response to said means for displaying the height differential between said reference reservoir and said sensing reservoir.
12. An apparatus as claimed in claim 11 wherein said means responsive to the liquid pressure in said sensing reservoir comprises a flexible container containing gas or air responsive to the liquid pressure in said sensing reservoir for providing gas or air pressure representative of the liquid pressure in said sensing reservoir to operate said gauge means for displaying the height differential between said reference reservoir and said sensing reservoir.
13. An apparatus as claimed in claim 12 wherein said reference reservoir is a flexible container.
14. An apparatus as claimed in claim 11 wherein said reference reservoir is a flexible container.
15. An apparatus as claimed in claim 11 wherein said means responsive to the liquid pressure in said sensing reservoir is disposed in said sensing reservoir.
16. An apparatus as claimed in claim 12 wherein said flexible container containing gas or air responsive to the liquid pressure in said sensing reservoir is disposed in said sensing reservoir.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US45193489A | 1989-12-18 | 1989-12-18 | |
| US451,934 | 1989-12-18 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2030030A1 true CA2030030A1 (en) | 1991-06-19 |
Family
ID=23794326
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA 2030030 Abandoned CA2030030A1 (en) | 1989-12-18 | 1990-11-15 | Hydro-pneumatic level |
Country Status (3)
| Country | Link |
|---|---|
| AU (1) | AU7341691A (en) |
| CA (1) | CA2030030A1 (en) |
| WO (1) | WO1991009272A1 (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1996018867A1 (en) * | 1994-12-12 | 1996-06-20 | Dietzsch & Rothe Msr-Technik Ohg | Level difference measurement apparatus |
Family Cites Families (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US872183A (en) * | 1907-03-19 | 1907-11-26 | Gustav A Jenning | Leveling instrument. |
| US1216129A (en) * | 1913-08-11 | 1917-02-13 | Gustav A Jenning | Leveling instrument. |
| US2557021A (en) * | 1946-09-12 | 1951-06-12 | Standard Oil Dev Co | Hydraulic system for measuring differences in elevation |
| EP0030221A1 (en) * | 1979-11-30 | 1981-06-10 | Amplikart S.P.R.L. | Water level that may be equipped with accessories |
| DD159362B1 (en) * | 1980-11-03 | 1986-07-16 | Gerd Schuchardt | ARRANGEMENT FOR TURNING VOLUME CHANGE EFFECTS ON A DEVICE FOR STRAIGHT & LEVEL MEASUREMENT |
| US4379367A (en) * | 1980-12-31 | 1983-04-12 | Marcel Legris | Electrically controlled level |
| FR2522137A1 (en) * | 1982-02-25 | 1983-08-26 | Abf | Hydraulic amplifier for e.g. inclinometer - uses two columns contg. liquids of different densities for measuring gradient, inclination, acceleration or weight |
| FR2542866B1 (en) * | 1983-03-18 | 1985-08-16 | Legris Marcel | APPARATUS FOR SEARCHING HORIZONTALITIES AND AUTOMATIC LEVELING OF CERTAIN PARTS |
| SU1174747A1 (en) * | 1983-07-13 | 1985-08-23 | Ставропольский Ордена "Знак Почета" Научно-Исследовательский Институт Сельского Хозяйства | Hydrostatic level |
| US4651433A (en) * | 1985-09-18 | 1987-03-24 | Mohr Henry G | Pressure sensitive leveling device |
| US4686773A (en) * | 1986-07-07 | 1987-08-18 | Brewer Aubrey W | Structure leveling system |
| US4759134A (en) * | 1986-11-26 | 1988-07-26 | Chrisley Barney D | Flexible level |
| SE460622B (en) * | 1988-04-21 | 1989-10-30 | Rolf Eriksson | LEVEL |
-
1990
- 1990-11-15 CA CA 2030030 patent/CA2030030A1/en not_active Abandoned
- 1990-12-17 AU AU73416/91A patent/AU7341691A/en not_active Abandoned
- 1990-12-17 WO PCT/US1990/007394 patent/WO1991009272A1/en unknown
Also Published As
| Publication number | Publication date |
|---|---|
| WO1991009272A1 (en) | 1991-06-27 |
| AU7341691A (en) | 1991-07-18 |
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