Abstract: A fine bubble generator may include an inlet; an outlet; a first fine bubble generation portion; and a second fine bubble generation portion. The first fine bubble generation portion includes: a diameter-reducing flow path and a diameter-increasing flow path. The second fine bubble generation portion includes: a first swirling flow generation portion; and a second swirling flow generation portion. The first swirling flow generation portion includes: a first outer peripheral portion; and a plurality of first vanes disposed configured to generate a first swirling flow flowing in a first swirling direction with respect to a center axis of the second fine bubble generation portion. The second swirling flow generation portion includes: a second outer peripheral portion; and a plurality of second vanes configured to generate a second swirling flow flowing in a second swirling direction opposite to the first swirling direction with respect to the center axis.

Abstract: In a gas governor, an auxiliary chamber divided by a separating wall from a main chamber that is a portion of the secondary pressure chamber is provided in the secondary pressure chamber, the auxiliary chamber communicates with the main chamber through a communicating passage, the separating wall is positioned at a portion away in a circumferential direction from an outflow-port opened portion that is a peripheral wall portion of the secondary pressure chamber, in which the outflow port is opened, and the separating wall is provided so that a distance from a valve hole and a curvature in the circumferential direction of at least an end portion of the separating wall, which is close to the valve seat, are equal to those of an end portion of the outflow-port opened portion, which is close to the valve seat.

Abstract: In a combustion apparatus that includes a burner constituted by a burner body, an inside of which an air-fuel mixture is supplied to and one surface of which is made into an open surface, and a combustion plate covering the open surface of the burner body, and a combustion box enclosing a combustion space of the air-fuel mixture ejecting from the combustion plate, an offset part that is positioned at a portion which is away from the swelling part in an inflow direction of the air-fuel mixture to the inner chamber and does not oppose to a tip part(s) of the ignition electrode(s) through the combustion plate is provided with the opposite wall of the burner body and the offset part offsets to a combustion-plate side so that a distance between the offset part and the combustion plate becomes shorter than that between the combustion plate and a general part of the opposite wall except the swelling part and the offset part.

Abstract: Not only a cylindrical weight is inserted with a clearance around an outside of a first axis part or a second axis part that extends opposite to the first axis part and is movable freely in an axial direction but also an annular seat surface on which the cylindrical weight is able to be seated by self-weight is provided with a governor valve. A projecting part(s) is provided with only a part in circumferential direction of one of the annular seat surface and a lower end surface of the cylindrical weight. The cylindrical weight is made sure to be supported on the annular seat surface in an inclined state from an upright posture by contact of the projecting part(s) with the other of the annular seat surface and the lower end surface of the cylindrical weight.

Abstract: In a combustion apparatus that includes a combustion plate having a burner frame with a shape of a picture frame, which covers an open surface of a burner body, and a frame flange part outwardly extending from a side plate part, which is sandwiched between a body flange part of the burner body and a box flange part of a combustion box, which is fastened to the body flange part, a projecting part(s) positioning the burner frame with respect to the combustion box, which comes into contact with, or comes close to and is disposed opposite to an inner surface of the combustion box is provided with the side plate part of the burner frame. Preferably, the projecting part(s) is provided at a portion away from an end of a side of an opening peripheral edge part of the side plate part to a side of the frame flange part.

Abstract: A fine bubble generating nozzle may include a nozzle unit and a baffle. The nozzle unit may include: an inlet; a pressure decreasing portion configured to decrease a pressure of a gas-dissolved pressurized water introduced from the inlet; a first collision chamber disposed downstream of the pressure decreasing portion and including a first collision wall with which the gas-dissolved pressurized water introduced from the pressure decreasing portion collides so that a flow direction of the gas-dissolved pressurized water changes; a second collision chamber disposed downstream of the first collision chamber and including a second collision wall with which the gas-dissolved pressurized water having flowed through the first collision chamber collides so that the flow direction of the gas-dissolved pressurized water changes; and an outlet. The baffle may be disposed outside of the nozzle unit and is disposed at a position facing the outlet.

Abstract: A fine bubble generator may include an inlet into which gas-dissolved water in which gas is dissolved flows, an outlet out of which the gas-dissolved water flows; and a fine bubble generation portion disposed between the inlet and the outlet. The fine bubble generation portion may include a venturi portion including a diameter-reducing flow path and a diameter-increasing flow path, wherein a flow path diameter of the diameter-reducing flow path reduces from upstream to downstream, and the flow path diameter of the diameter-increasing flow path increases from upstream to downstream, a discharging flow path configured to discharge the gas-dissolved water, which flowed out of the venturi portion, out of the fine bubble generation portion; and a recirculation flow path connecting a midstream of the outflow path and the venturi portion.

Abstract: A fine bubble generator may include an inlet, an outlet, a first fine bubble generation portion including a first flow path, and a second fine bubble generation portion including a second flow path. The first flow path may include a diameter-reducing flow path and a diameter-increasing flow path. The second flow path may include a guide flow path and a collision flow path disposed downstream of the guide flow path. A first bearing and a first impeller rotatably attached to the first bearing may be disposed on the collision flow path. The first impeller may include a disc disposed at a position at which the gas-dissolved water collides with the disc; a first rotation shaft disposed on a downstream surface of the disc and rotatably attached to the first bearing; and one or more first vanes disposed on an upstream surface of the disc.

Abstract: Not only a cylindrical weight is inserted with a clearance around an outside of a first axis part or a second axis part that extends opposite to the first axis part and is movable freely in an axial direction but also an annular seat surface on which the cylindrical weight is able to be seated by self-weight is provided with a governor valve. A projecting part(s) is provided with only a part in circumferential direction of one of the annular seat surface and a lower end surface of the cylindrical weight. The cylindrical weight is made sure to be supported on the annular seat surface in an inclined state from an upright posture by contact of the projecting part(s) with the other of the annular seat surface and the lower end surface of the cylindrical weight.

Abstract: A gas manifold allows each distribution chamber to be fed with fuel gas at an appropriate flow rate irrespective of an increase in the number of distribution chambers included in the gas manifold. Fuel gas flowing through in an inlet is distributed to a plurality of distribution chambers through a main channel. A bypass channel parallel with the main channel also feeds fuel gas to a maximum distribution chamber. This can prevent the feeding of the fuel gas to the maximum distribution chamber from being affected by and reduced by the feeding of the fuel gas to the bypassed distribution chambers. This also prevent the feeding of the fuel gas to the other distribution chambers from being affected by and reduced by the feeding of the fuel gas to the maximum distribution chamber. The plurality of distribution chambers are thus fed with fuel gas at appropriate flow rates.

Abstract: In a premixing apparatus that mixes a fuel gas with air and supplies an air-fuel mixture to a burner through a fan, includes a main valve, a zero governor, and a variable throttle valve which are interposed from an upstream side downward in sequence in a gas supply passage, of which an downstream end is connected to a gas suction part that is provided in an air supply passage on an upstream side of a fan, and carries out a first control that regulates an opening degree of the variable throttle valve so that an excess air ratio of the air-fuel mixture, which is indexed based on a flame current that is detected by a flame rod which is exposed in flames of the burner, and a second control that, at time of a post-purge operation, if the flame rod detects the flame current, it will be decided that an open trouble of the main valve occurs and the opening degree of the throttle valve will be tightened till a minimum opening-degree which is set so that the burner is extinguished.

Abstract: In a premixing apparatus that mixes a fuel gas with air, supplies an air-fuel mixture to a burner through a fan, and carries out a control that regulates an opening degree of a variable throttle valve, which is interposed in a gas supply passage, so that an excess air ratio of an air-fuel mixture becomes an appropriate value, in a case where a detected excess air ratio deviates to one side, e.g., a large side, from an acceptable range, a motor is repeatedly caused to rotate by a unit-angle in an opening-degree increasing direction until the detected excess air ratio becomes an appropriate value. In a case where the detected air ratio deviates to the other side, e.g.

Abstract: In a fan apparatus that includes a passage, a switching device, and a control device, on a premise that at a state where an effective sectional area at a predetermined portion of the passage is switched to a predetermined first-area by the switching device, a value of a current flowing to the fan when a rotational speed of the fan is made to a predetermined rotational speed is defined as a first fan-current value, at a state where the effective sectional area at the predetermined portion of the passage is switched to a predetermined second-area which is larger than that of the first area by the switching device, the value of the current flowing to the fan when the rotational speed of the fan is made to the predetermined rotational speed is defined as a second fan-current value, and a ratio of the first fan-current value to the second fan-current value is defined as a detected current ratio, a control device is configured to: memorize as a standard current ratio a detected current ratio that is detected when t

Abstract: In a combustion apparatus that includes a heat exchanger which is disposed in a combustion box, on a premise that a direction from a burner to the heat exchanger is defined as a Z-axis plus direction, a direction opposite to the Z-axis plus direction is defined as a Z-axis minus direction, and an orthogonal direction to a Z-axis direction, which is along fins of the heat exchanger is defined as a X-axis direction, a thermal insulation material is arranged on an inner surface of a swelling part that is formed at a side plate part of a combustion box and outwardly swells in the X-axis direction so as to be sandwiched from both sides in the Z-axis direction by a step that is outwardly bent in the X-axis direction, which is positioned an end, in the Z-axis plus direction, of the swelling part and a structural member of a burner, which inwardly protrudes in the X-axis direction from an end, in the Z-axis minus direction, of the side plate part.

Abstract: A rich-lean flame burner having on an upper part thereof: a longitudinally elongated lean burner port; and a rich burner port lying adjacent to at least one lateral side of the lean burner port with a clearance therebetween. At a plurality of longitudinal points of straightening members having a plurality of straightening plates which divide the lean burner port into a plurality of laterally sectioned regions, there are disposed first constricted portions which bring upper parts of the straightening plates into intimate contact with each other. Second constricted portions are disposed in at least laterally outermost straightening plates to further divide each portion of the lean burner port that has been divided by the first constricted portions. The second constricted portions are such that the lower end thereof is positioned above the lower end of the first constricted portions, and that the vertical length is shorter than the first constricted portions.

Abstract: A combustion device may include a casing including a bottom plate, a combustion unit housed in the casing, and a fan housed in the casing and configured to take in air inside the casing and supply the air to the combustion unit. The bottom plate may be provided with a flat portion and a recess recessed downward from the flat portion. The recess may be provided with a drainage hole and an eave arranged above the drainage hole. The drainage hole may be located below an upper surface of the flat portion. The eave may be at least partially located below the upper surface of the flat portion.

Abstract: A premixing apparatus that mixes a fuel gas with air and supplies an air-fuel mixture in a burner through a fan includes a control device that is configured to carry out a third control that: calculates and memorizes a lower limit of a rotational speed of a fan, at which an increase of an opening degree of a variable throttle valve becomes necessary, as a first threshold; and when the rotational speed of the fan increases to the first threshold or faster next time, immediately changes the opening degree of the variable throttle valve to an increased opening degree, which is larger than a predetermined standard opening degree and is obtained by multiplying a deviation of the rotational speed of the fan from the first threshold by a predetermined coefficient.

Abstract: A flow regulating valve in which a needle valve body is arranged to be moved axially by a motor through a motion conversion mechanism. The motion conversion mechanism has: a guide member having formed therein axially elongated slits with which cam pins fixed to the needle valve body are slidably engaged, the guide member being coupled to the motor; and a cam body having formed spirally shaped cam parts with which the cam pins are engaged such that the cam body is prevented from rotating relative to a valve casing. The valve casing includes inside thereof a deformation-restricting element having a female type of fitting part into the inside of which the forward-direction-side end part of the cam body gets fitted.

Abstract: An outer peripheral edge part of the air-fuel mixture permeable member is connected to a portion away outward by a predetermined distance from an inner peripheral edge of the burner frame. Between the burner frame and the air-fuel mixture permeable member a clearance reaching the inner peripheral edge of the burner frame is secured at a position inward of the outer peripheral part of the air-fuel mixture permeable member. Preferably, a bent edge part formed on an inner peripheral edge of the burner frame, in a manner to be bent toward the air-fuel mixture permeable member. The amount of the air-fuel mixture to flow into the clearance is limited to a smaller amount.

Abstract: A totally aerated combustion burner has a combustion plate part through which an air-fuel mixture is ejected. The combustion plate part includes: an air-fuel mixture permeable body made from metallic fibers to allow the air-fuel mixture to pass therethrough; and a distribution plate having formed therein a multiplicity of distribution holes and being stacked on a back surface of the air-fuel mixture permeable body. An air-fuel mixture permeable body is constructed by laminating a plurality of metallic-fiber woven bodies which are woven by metallic-fiber threads obtained by bundling a plurality of metallic fibers relatively large in diameter. These metallic-fiber woven bodies are laminated such that a part of meshes in one metallic-fiber woven body overlaps a portion other than meshes in another metallic-fiber woven body, said one metallic-fiber woven body and said another metallic-fiber woven body that lies adjacent to each other in the laminating direction.