US3599865A - Thermohydraulic control device - Google Patents

Thermohydraulic control device Download PDF

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Publication number
US3599865A
US3599865A US848455A US3599865DA US3599865A US 3599865 A US3599865 A US 3599865A US 848455 A US848455 A US 848455A US 3599865D A US3599865D A US 3599865DA US 3599865 A US3599865 A US 3599865A
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United States
Prior art keywords
cylinder
piston
tooth
temperature
control device
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.)
Expired - Lifetime
Application number
US848455A
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English (en)
Inventor
Svend Helge Kristiansen
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Novenco Building and Industry AS
Original Assignee
Nordisk Ventilator Co
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Filing date
Publication date
Priority claimed from DK392368A external-priority patent/DK124362B/da
Application filed by Nordisk Ventilator Co filed Critical Nordisk Ventilator Co
Application granted granted Critical
Publication of US3599865A publication Critical patent/US3599865A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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    • G—PHYSICS
    • G05—CONTROLLING; REGULATING
    • G05D—SYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES
    • G05D23/00—Control of temperature
    • G05D23/01—Control of temperature without auxiliary power
    • G05D23/12—Control of temperature without auxiliary power with sensing element responsive to pressure or volume changes in a confined fluid
    • G05D23/125—Control of temperature without auxiliary power with sensing element responsive to pressure or volume changes in a confined fluid the sensing element being placed outside a regulating fluid flow
    • G05D23/126—Control of temperature without auxiliary power with sensing element responsive to pressure or volume changes in a confined fluid the sensing element being placed outside a regulating fluid flow using a capillary tube
    • G05D23/127—Control of temperature without auxiliary power with sensing element responsive to pressure or volume changes in a confined fluid the sensing element being placed outside a regulating fluid flow using a capillary tube to control a gaseous fluid circulation
    • A—HUMAN NECESSITIES
    • A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
    • A01K—ANIMAL HUSBANDRY; AVICULTURE; APICULTURE; PISCICULTURE; FISHING; REARING OR BREEDING ANIMALS, NOT OTHERWISE PROVIDED FOR; NEW BREEDS OF ANIMALS
    • A01K1/00—Housing animals; Equipment therefor
    • A01K1/0047—Air-conditioning, e.g. ventilation, of animal housings
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F11/00—Control or safety arrangements
    • F24F11/70—Control systems characterised by their outputs; Constructional details thereof
    • F24F11/72—Control systems characterised by their outputs; Constructional details thereof for controlling the supply of treated air, e.g. its pressure
    • F24F11/74—Control systems characterised by their outputs; Constructional details thereof for controlling the supply of treated air, e.g. its pressure for controlling air flow rate or air velocity
    • F24F11/76—Control systems characterised by their outputs; Constructional details thereof for controlling the supply of treated air, e.g. its pressure for controlling air flow rate or air velocity by means responsive to temperature, e.g. bimetal springs
    • G—PHYSICS
    • G05—CONTROLLING; REGULATING
    • G05D—SYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES
    • G05D23/00—Control of temperature
    • G05D23/01—Control of temperature without auxiliary power
    • G05D23/02—Control of temperature without auxiliary power with sensing element expanding and contracting in response to changes of temperature
    • G05D23/021—Control of temperature without auxiliary power with sensing element expanding and contracting in response to changes of temperature the sensing element being a non-metallic solid, e.g. elastomer, paste
    • G—PHYSICS
    • G05—CONTROLLING; REGULATING
    • G05D—SYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES
    • G05D23/00—Control of temperature
    • G05D23/01—Control of temperature without auxiliary power
    • G05D23/02—Control of temperature without auxiliary power with sensing element expanding and contracting in response to changes of temperature
    • G05D23/021—Control of temperature without auxiliary power with sensing element expanding and contracting in response to changes of temperature the sensing element being a non-metallic solid, e.g. elastomer, paste
    • G05D23/022—Control of temperature without auxiliary power with sensing element expanding and contracting in response to changes of temperature the sensing element being a non-metallic solid, e.g. elastomer, paste the sensing element being placed within a regulating fluid flow
    • G—PHYSICS
    • G05—CONTROLLING; REGULATING
    • G05D—SYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES
    • G05D23/00—Control of temperature
    • G05D23/01—Control of temperature without auxiliary power
    • G05D23/12—Control of temperature without auxiliary power with sensing element responsive to pressure or volume changes in a confined fluid
    • G05D23/125—Control of temperature without auxiliary power with sensing element responsive to pressure or volume changes in a confined fluid the sensing element being placed outside a regulating fluid flow
    • G05D23/126—Control of temperature without auxiliary power with sensing element responsive to pressure or volume changes in a confined fluid the sensing element being placed outside a regulating fluid flow using a capillary tube

Definitions

  • thermohydraulic control device for a ventilation or air supply damper consisting of a hydraulic motor, comprising a cylinder in which a plunger piston is movably disposed, the volume of thecylinder being of such a size relative to its cross-sectional area that the cylinder can at the same [54] THERMOHYDRAULIC CONTROL DEVICE time act as a temperature-responsive element, the piston pin 7 claimss Drawmg Flgs' of the plunger piston being coupled to the damper shaft by [52] U.S.
  • Cl 236/99 means of a single-toothed rack and pinion wheel connection 98/32,236/49,25l/250 having engagement surfaces which lock the damper in the [51] Int. Cl F24f 13/08 open or the closed position, respectively, when the tooth of [50] Field of Search 236/49, 99, the rack is out of engagement with the single tooth-space of lOO, 98; 251/248, 250; 98/32, 33 the tooth wheel.
  • thermohydraulic control device for the temperature-responsive control of regulating dampers, particularly for the ventilation of stables, e.g. a stable fan with an extraction pipe and an injection pipe mounted concentrically therewith, which device has a liquid-filled cylinder and a plunger piston movable therein by changes in the liquid content of the cylinder, which changes are produced by fluctuations in temperature.
  • the known control devices of this kind comprise a hydraulic adjustment motor which is connected with a temperature sensor via a narrow tube and is of a rather complicated design. They are frequently employed in connection with central heating installations, for instance for the regulation of a radiator valve.
  • thermohydraulic control device an electric motor is used for this purpose, as an adjustment motor and an electronic temperature-responsive control of same instead of a thermohydraulic control device.
  • An electric control device is, however, particularly costly, and where it is a question of controlling several uniform elements, e.g. several fans used in a stable, one will therefore forego an individual regulation and will control all of them in common by means of the same adjustment motor, the individual elements being, in a suitable manner, coupled mechanically.
  • thermohydraulic control device is characteristic in that the volume of the cylinder is of such a dimension in relation to its diameter, that within the normal range of temperature fluctuations the change in volume of the quantity of liquid contained solely in the cylinder owing to these fluctuations, is great enough to cause a travel of the piston corresponding at least to the adjustment movement desired and preferably a considerably longer travel, and that for the conversion of the displacement of the piston into a rotation of the adjustment shaft of the damper, a single-toothed rack and pinion coupling is inserted between the shaft and a rod rigidly connected with the piston, said coupling having one tooth that is rigidly connected to the piston and a wheel having only one tooth space, said tooth having a flat surface situatedparallelto the direction of movement, which surface is in contact with a corresponding flat surface on the wheel in positions in which the tooth is not engaged with the tooth space.
  • the control of the quantity of fresh air takes place in that the regulating device dealt with adjusts the damper to an aperture dependent on the stable temperature, i.e. that a change in the stable temperature brings about a rotation of the damper to a larger or smaller aperture, depending on whether the change in temperature constitutes a rise or a fall in the temperature.
  • the temperature change that is required in order to cause the damper to move from a fully closed to a fully open position must not be too small, as in such a case fluctuations occur.
  • the temperature change in the stable temperature has to be of 4-5 C. in order to turn the damper from a fully open to a fully closed position.
  • the damper is going to be fully open for a supply of fresh air at a sensor temperature-and thereby stable temperature, of 20 C.
  • a relatively high outside temperature where a large supply of fresh air is required in order to remove the excess heat in the stable.
  • the temperature in the stable will start to decrease. This causes the sensor temperature to fall and thereby to reduce the supply of fresh air further.
  • the sensor will adjust the damper until a balance between the quantity of fresh air supplied and the generation of heat in the stable has been restored. This adjustment can only take place by the sensor temperature, and with it the stable temperature, having become lower.
  • a closing of the damper to e.g. 20 percent fresh air will correspond to a reduction in the sensor temperature and with it the stable temperature of 4 C., thus in the present example to 16 C.
  • the cylinder is, moreover, connected with an outside sensor for the variation in the quantity of liquid in the cylinder, which outdoor sensor contains a quantity of liquid constituting the fraction of the quantity of liquid in the cylinder necessary for the desired compensation.
  • FIG. 1 shows a part of an embodiment of a thermohydraulic control device according to the invention
  • FIG. 2 the connection of the device to two damper shafts for the adjustment of two symmetrical damper parts
  • FIG. 3 the device shown in FIGS. 1 and 2 mounted together with a stable fan
  • FIG. 4 a section after the lines IV-IV in FIG. 2, and
  • FIG. 5 an outdoor sensor to be used in connection with the device shown in FIG. 1.
  • FIG. I an elongated cylinder I with a plunger piston 2 is shown.
  • the cylinder 1 is at one end closed by a bottom piece 3 and at the opposite end provided with a mounting collar 4.
  • a bushing 5 is disposed that forms a guide for the piston 2 and which is secured by means of a cover plate 6 which is bolted to the flange 4.
  • packings 7 and 8 are inserted between the cover plate 6 and the piston 7 and between the flange 4 and the bushing 5, respectively.
  • a sleeve 9 is fixed and between this sleeve 9 and the bushing 5 a spiral spring 10 is inserted.
  • the part of the control device described above constitutes, at the same time, a hydraulic adjustment motor and a temperature sensor, in that the cylinder 1 is sufficiently long in relation to its cross section, e.g. having a length of up to 50 times its diameter, so that the variation in volume of a liquid contained in the cylinder through a temperature fluctuation within a suitable control interval can bring about the displacement of the piston 2 necessary for the desired adjustment.
  • the end of the piston 2 extending outside the cylinder constitutes a rack with a single tooth 11 at each side serving for the transmission of the linear movements of the piston to the adjustment movement, which is a rotary movement, in a way as shall be described in greater detail below in connection with FIG. 2.
  • a tube 12 is fitted in the bottom piece 3 connecting the inside of cylinder I with the inside ofa cylinder 13 with a piston 14.
  • the piston 14 penetrates through a sleeve 15 that is screwed into the cylinder 13 and which tightens against a sealing ring 38 which produces sealing between the cylinder and the piston.
  • the bushing 15 has an exterior thread, by means of which it is screwed into an outer cylinder 16 which, at the end situated opposite to the cylinder 13, is provided with an axial screw 17 which abuts against the end of the piston 14 and is provided with a counter nut 18.
  • the cylinder 13 has a temperature scale 19 on its outer surface.
  • the unit described above connected with the cylinder via a pipeline 12 serves for the adjustment of the control device, since a displacement of the piston 14 in the cylinder 13 will bring about a change in the amount ofliquid in the cylinder 1 and by this means a corresponding movement of the piston 2.
  • a displacement is brought about by the outer cylinder 16 being more or less screwed down over the cylinder 13, by which means the screw 17 rigidly connected with the cylinder 16 occasions the displacement of the piston 14.
  • the quantity of liquid contained in the cylinder 13 and the pipeline l2 constitutes such a small fraction of the quantity of liquid contained in the cylinder that it has no bearing upon the functioning of the control device in dependence of temperature fluctuations.
  • FIG. 2 shows the connection between the piston 2 and two adjustments shafts 20 and 21 for a damper with two symmetrical halves each mounted on one of the two shafts, but not shown in FIG. 2.
  • connection is a rack and pinion coupling, in that the two members 23 that are fixed each on their respective shafts 20 and 21 and constructed with a tooth space 24, with which the tooth 11 is engaged.
  • the members 23 may therefore be regarded as tooth wheels, in which the toothing is reduced to the one tooth gap which is the only effective one, because'the rack interacting with the tooth wheels has only one single tooth.
  • the two single teeth and the tooth spaces are constructed in such a way that each of the two teeth precisely disengages from the corresponding tooth space in each of the two extreme positions ofthe shafts 20 and 21,
  • each of the two single teeth 11 are shaped as a flat surface 22 that is parallel to the direction of movement of shaft 2.
  • the members 23 are for the sake of safety provided with extensions 27, on which the surfaces 25 continue into surfaces 28, in a way that even at a very high temperature it is ensured that the damper is kept in a fully open position.
  • the described construction of the movement transmission mechanism is a very essential feature of the contml device as a whole, since the complicated measures which otherwise have to be taken in thermohydraulic control devices for the limitation of the movement of the piston at temperatures exceed ng the control interval, are avoided altogether, and such measures would in praxis be exceedingly difficult to carry out when the hydraulic adjustment motor and the temperature sensor are constituted of one and the same element and are to render possible a large adjustment movement within the control interval.
  • the parts described are disposed in a housing 29 which is bolted to the flange 4.
  • This housing 29 and the cylinder 1 are shown in FIG. 3, where the described control device is mounted on a stable fan.
  • the two damper parts 34 and 35 of the fan which are mounted on the shafts 20 and 21, are adjusted by means of the control device.
  • the cylinder 1 of the device acting as a temperature sensor is disposed directly in the airflow extracted from the stable, in that it is situated axially in the duct 30.
  • the damper parts are connected with counterweights 36 and 37, respectively.
  • a control device like the one described may be used in an analogous manner for the adjustment of a damper having a single adjustment shaft.
  • the guide for the piston 2 is dimensioned in such a way as to be able to absorb the radial forces which can occur, while these, on account of the symmetry in the construction described, act as equally strong forces in the opposite direction and consequently do not affect the control of the piston.
  • FIG. 4 shows a particularly expedient embodiment of the two members or tooth wheels 23, in that these are formed of slats 40 and 41.
  • the slats 40 are of such a shape that they form the said extensions 27 on the members 23, while the slats 41 are made without these extensions and the slats are mounted in a way that the slats 40 on the one member 23 are situated facing the slats 41 on the other member 23, viz.
  • the one member consists of a bundle of slats 40 with a bundle of slats 41 on each side, and on the other one of a bundle of slats 41 with a bundle of slats 40 on each side.
  • the outside sensor shown in FIG. 5 comprises a cylinder 51 which, via a pipeline 52, is destined to be connected to the liquid-filled cylinder described, with reference to FIG. 1 which constitutes the actual control device.
  • a displaceable piston 53 is fitted, in that the necessary sealing is produced by means of a sealing ring 54, which-is tightened by means of a cylindrical top piece 55 screwed on to the cylinder 51.
  • an adjustment screw 56 is screwed, which serves for the adjustment to a larger or smaller volume of the liquid in the cylinder 51.
  • the size of this volume depends on the influence the outside temperature is desired to have on the adjustment of the fan carried out by means of the screw.
  • the influence of the outside temperature on the regulation in a change in the outside temperature of 20 C. corresponds to a change in the inside temperature of 4 C. and full compensation is desired, so that a drop in the outside temperature does not bring about any change in the stable temperature, it will, depending on the dimensioning of the control device, generally be sufficient that the quantity of liquid which is contained in the cylinder 51 constitutes 20-25 percent of the quantity of liquid in the control device itself.
  • the degree of compensation can, in the embodiment shown, be adjusted by means of the screw 56 and it may thus be sometimes desirable to adjust to a certain slight overcompensation, for instance, in such a way that a temperature rise of l-2 C. occurs in the stable when there is a drop of l0 C. in the outside temperature.
  • the volume of the container may be dimensioned to produce a certain overcompensation, if this is desired.
  • thermohydraulic control device for the temperatureresponsive control of a regulating damper comprising, a liquid-filled cylinder and a plunger piston movable in said cylinder by the expansion and contraction of the liquid content of said cylinder due to temperature fluctuations, said piston having a piston rod rigidly connected'therewith, a control shaft for said damper, coupling means being inserted between said shaft and said piston rod comprising a single tooth rack connected to said piston and a wheel having only one tooth space connected to said shaft, said tooth engaging said wheel and having an end surface, said wheel being provided with corresponding surfaces on opposite sides of said tooth space engageable with said end surface of said tooth when said tooth is moved outside said tooth space to positively maintain said shaft in the adjust position during continued movement of said piston.
  • a control device as claimed in claim 1 in which said cylinder is, moreover, connected with an outdoor sensor for the variation of the quantity of liquid in said cylinder, said outdoor sensor containing a quantity of liquid which constitutes the fraction of the quantity of liquid in said cylinder necessary for the compensation for variations of the temperature of said sensor.
  • thermohydraulic control device for the temperatureresponsive control of a regulating damper consisting of two symmetrical damper parts comprising, a liquid filled cylinder and a plunger piston movable in said cylinder by the expansion and contraction of the liquid content of said cylinder due to temperature fluctuations, said piston having a piston rod rigidly connected therewith, a control shaft for each of said damper parts, said control shafts being disposed parallel to each other, coupling means being inserted between said shafts and said piston rod comprising a rack having two single teeth connected to said piston and extending in opposite directions and a wheel having only one tooth space connected to each of said shafts, each of said teeth engaging a respective wheel and having an end surface, each ofsaid wheels being provided with corresponding surfaces on opposite sides of said tooth space engageable with said end surface of each tooth when said teeth are moved outside said too h spaces to positively maintain said shafts in the adjusted position during continued movement of said piston.
  • each of said wheels is comprised of a plurality of punched slats some of which are provided with elongated extensions which will cross each other in one extreme position of said piston, said elongated extensions having opposed surfaces disposed parallel to each other in the other extreme position of said piston.

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  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • General Physics & Mathematics (AREA)
  • Automation & Control Theory (AREA)
  • Fluid Mechanics (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Environmental Sciences (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Combustion & Propulsion (AREA)
  • Zoology (AREA)
  • Animal Husbandry (AREA)
  • Biodiversity & Conservation Biology (AREA)
  • Chemical & Material Sciences (AREA)
  • Fluid-Damping Devices (AREA)
  • Control Of Temperature (AREA)
  • Transmission Devices (AREA)
US848455A 1968-08-14 1969-08-08 Thermohydraulic control device Expired - Lifetime US3599865A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DK392368A DK124362B (da) 1968-08-14 1968-08-14 Termohydraulisk reguleringsmekanisme.
DK125469 1969-03-06

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US3599865A true US3599865A (en) 1971-08-17

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US848455A Expired - Lifetime US3599865A (en) 1968-08-14 1969-08-08 Thermohydraulic control device

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US (1) US3599865A (enrdf_load_stackoverflow)
DE (1) DE1940899A1 (enrdf_load_stackoverflow)
FR (1) FR2015663A1 (enrdf_load_stackoverflow)
GB (1) GB1273173A (enrdf_load_stackoverflow)
NL (1) NL6912315A (enrdf_load_stackoverflow)
SE (1) SE354714B (enrdf_load_stackoverflow)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3722396A (en) * 1970-11-16 1973-03-27 Nordisk Ventilator System for the ventilation of buildings
US4630873A (en) * 1983-11-24 1986-12-23 Messer Griesheim Gmbh Apparatus for low temperature storage of biological or pharmaceutical samples
US5816493A (en) * 1996-04-08 1998-10-06 Texan Corporation Thermally expansible compositions methods for preparation and devices using same
US6029648A (en) * 1997-12-29 2000-02-29 Willis; W. Coy Outside wood-burning furnace
CN103615545A (zh) * 2013-11-21 2014-03-05 浙江金锋自动化仪表有限公司 一种可定点调节温度的自力式温度调节器

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
RU2217714C2 (ru) * 2001-12-21 2003-11-27 Васин Владимир Анатольевич Датчик-реле температуры (варианты)

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2081842A (en) * 1933-12-29 1937-05-25 Baldwin Southwark Corp Pivot valve and sealing means
US3207438A (en) * 1962-10-06 1965-09-21 Huber & Cie A G J Regulating valve for manual and automatic actuation
US3463391A (en) * 1967-04-26 1969-08-26 Big Dutchman Intern Ag Air duct assembly,particularly for a stable or the like

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2081842A (en) * 1933-12-29 1937-05-25 Baldwin Southwark Corp Pivot valve and sealing means
US3207438A (en) * 1962-10-06 1965-09-21 Huber & Cie A G J Regulating valve for manual and automatic actuation
US3463391A (en) * 1967-04-26 1969-08-26 Big Dutchman Intern Ag Air duct assembly,particularly for a stable or the like

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3722396A (en) * 1970-11-16 1973-03-27 Nordisk Ventilator System for the ventilation of buildings
US4630873A (en) * 1983-11-24 1986-12-23 Messer Griesheim Gmbh Apparatus for low temperature storage of biological or pharmaceutical samples
US5816493A (en) * 1996-04-08 1998-10-06 Texan Corporation Thermally expansible compositions methods for preparation and devices using same
US6029648A (en) * 1997-12-29 2000-02-29 Willis; W. Coy Outside wood-burning furnace
CN103615545A (zh) * 2013-11-21 2014-03-05 浙江金锋自动化仪表有限公司 一种可定点调节温度的自力式温度调节器
CN103615545B (zh) * 2013-11-21 2015-11-11 浙江金锋自动化仪表有限公司 一种可定点调节温度的自力式温度调节器

Also Published As

Publication number Publication date
NL6912315A (enrdf_load_stackoverflow) 1970-02-17
GB1273173A (en) 1972-05-03
FR2015663A1 (enrdf_load_stackoverflow) 1970-04-30
SE354714B (enrdf_load_stackoverflow) 1973-03-19
DE1940899A1 (de) 1970-02-26

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