Abstract: A rotor blade comprises a blade platform and an airfoil. The airfoil comprises a blade tip, a leading edge, and a trailing edge with a stiffening compound lean contour. The blade tip is radially opposite the blade platform, and defines a blade span between the blade itself and the blade platform. The leading and trailing edges extend from the blade platform to the blade tip to define blade chords between the leading edge and the trailing edge. The compound lean contour comprises a positive lean section located at the lean tip, and extending along a lean axis to a lean end. The negative lean section is located radially inward of the positive lean section, and extends along the lean axis to the lean end.

Abstract: A system includes an airfoil that includes a first suction portion of a nominal airfoil profile in accordance with Cartesian coordinate values of X, Y, and Z of a suction side as set forth in TABLE I, wherein the X and Y values of the suction side are coordinate values that couple together to define suction side sections of the first suction portion of the nominal airfoil profile at each Z coordinate value, the suction side sections of the first suction portion of the nominal airfoil profile are coupled together to define the first suction portion, the airfoil includes an airfoil length along a Z axis, the first suction portion includes a first portion length along the Z axis, the first portion length is less than or equal to the airfoil length, and the Cartesian coordinate values of X, Y, and Z are non-dimensional values convertible to dimensional distances.

Abstract: A coating including a CMAS-resistant layer with a rare earth oxide. The CMAS-resistant layer is essentially free of zirconia and hafnia, and may further include at least one of alumina, silica, and combinations thereof.

Abstract: A turbine airfoil for a rotating blade or stationary nozzle vane includes an airfoil body including a leading edge and a trailing edge. A coolant supply passage extends within the airfoil body, and a coolant return passage extends within the airfoil body. A first trench is in an external surface of the airfoil body, the first trench extending to the trailing edge and being in fluid communication with the coolant supply passage. A second trench is in the external surface of the airfoil body, the second trench extending to the trailing edge and being in fluid communication with the coolant return passage and the first trench. A cover seats in the airfoil body and encloses the trenches to form coolant passages with the airfoil body. In embodiments, two coolant passages to and back from the trailing edge may be used to allow for a recycling flow.

Abstract: A seal assembly is provided that extends along an axial centerline, and includes a rotor seal element that engages with a stator seal element. The rotor seal element extends radially between an inner element side and an outer element side, and includes a channel, a plurality of first passages and a plurality of second passages. The channel extends radially into the rotor seal element from the inner element side. The first and the second passages are fluidly coupled with the channel. Each of the first passages extends radially through the rotor seal element to a respective first passage outlet. Each of the second passages extends axially through the rotor seal element to a respective second passage outlet.

Abstract: A seal assembly for a gas turbine engine according to an example of the present disclosure includes, among other things, a housing, a seal carrier secured to the housing and configured to be selectively biased from the housing, and a wedge seal secured to the seal carrier and configured to abut against at least two sealing surfaces. A method of sealing between adjacent components of a gas turbine engine is also disclosed.

Abstract: A vane assembly for a gas turbine engine is disclosed in this paper. The vane assembly includes an inner platform, an outer platform, and a ceramic-containing airfoil. The ceramic-containing airfoil extends from the inner platform to the outer platform. A clamp mechanism couples the inner platform and the outer platform to the ceramic-containing airfoil.

Abstract: A seal for sealing a gap between a vane and a liner of an outlet guide vane is provided. The seal includes: a joint section for joining with the liner; a flexible fillet section elongated from the joint section and tapering toward a tip so as to form a round corner between the vane and the liner when the tip is placed in contact with the vane; and a flexible rib section projecting from an inner surface and so dimensioned as to get in contact with an upper surface of an external structure for securing the vane to keep gas tightness.

Abstract: The invention refers to a blade of a rotary flow machine including an airfoil having a suction surface and a pressure surface joining each other along a trailing and a leading edge. A radially outward directed airfoil tip and a radially inward directed end joining an inner platform connect the airfoil to a shank at a radial end of the airfoil and providing, at least one shank pocket radially encircled by an axially extending portion of the platform. At least one radially extending rim extends from the trailing edge side of the shank and has an essentially radially orientated first slot for receiving a seal. A mount extends radially inwardly from said shank pocket. The first slot has a first aperture on a shank surface orientated in an axial direction.

Abstract: A turbine blade, including: an airfoil and a platform, which has an upper face on which the airfoil is arranged; and at least one lateral face, the lateral face including a slot for insertion of a sealing strip. The transition between the upper face of the platform and the at least one lateral face includes a stepped portion and a beveled portion is provided.

Abstract: A power plant for an aircraft such as an unmanned aero vehicle in which a gas turbine engine drives an electric generator to produce electrical power for a system load of the aircraft. An engine control unit monitors engine performance and regulates engine power output through fuel flow control to a combustor. A power control module regulates power output of the generator to the system load and to a battery through a bus. A pulse width modulation is used between the power control module and the bus to optimize performance of the gas turbine engine instead of adjusting fuel flow to the combustor.

Abstract: Stator vane assembly includes plurality of vanes arranged in circumferential array, radially proximal mounting portion, radially distal mounting portion, and first latching mechanism. Each of plurality of vanes extends radially between radially proximal mounting portion and radially distal mounting portion, with each of plurality of vanes being pivotally mounted between radially proximal mounting portion and radially distal mounting portion. Plurality of vanes is movable between first arrangement allowing gas to flow across vanes, and second arrangement blocking gas flow across vanes. Pivot axis of each of plurality of vanes is offset from the line of aerodynamic center of pressure of vane towards trailing edge of vane, and first latching mechanism holds plurality of vanes in first arrangement. Upon receipt of signal, first latching mechanism releases plurality of vanes so that gas flow through vane assembly causes plurality of vanes to move from first arrangement to second arrangement.

Abstract: A position adjustment device is provided with an eccentric pin and a push rod. The eccentric pin has a rotating shaft part, and an eccentric shaft part inserted into an end in a circumferential direction of a lower-half inside member. The push rod is inserted into the lower-half inside member from an end surface in the circumferential direction of the lower-half inside member, the push rod being able to come into contact with the eccentric shaft part within the lower-half inside member. The rotating shaft part has a columnar shape with a rotational axis line. The eccentric shaft part is formed with: a side peripheral surface that comes into contact with the inner peripheral surface of an eccentric shaft hole in the lower-half inside member into which the eccentric shaft part is inserted, and a rod contact surface that comes into contact with the push rod.

Abstract: In accordance with one aspect of the present technique a method includes receiving at least one of a speed and an acceleration of a rotating component in a rotating machine. The method includes determining whether at least one of the speed and the acceleration of the rotating component exceeds a non-trip operating (NTO) space in a speed-acceleration plane, wherein the NTO space is based on a trip overshoot model. The method further includes sending a notification for tripping the rotating machine in response to determining that at least one of the speed and the acceleration of the rotating component exceeds the NTO space.

Abstract: A gas turbine engine (20) and method for containing a fan inside an engine after a fan thrust bearing assembly failure. The engine (20) may comprise a fan (42), a housing (100) including a compartment (102), a fan shaft (104) inside the compartment (102) and comprising a bowl (108), a support structure (110) inside the compartment (102), a speed sensor pickup (114) mounted on the outer surface (120) of the bowl (108), a speed sensor (112) mounted on the support structure (110), and a fan thrust bearing assembly (41) disposed forward of the bowl (108). The fan thrust bearing assembly (41) including a bearing (126). The speed sensor (112) and the sensor pickup (114) define a defining a sensor gap (116). The bearing (126) and the outer surface (120) defining a fan thrust bearing gap (130), wherein the sensor gap (116) is less than the fan thrust bearing gap.

Abstract: According to one aspect of the present disclosure, a debris monitoring system is disclosed that includes a fan, a geared architecture operatively coupled to the fan. The geared architecture includes a component having a non-ferrous metal coating. A scavenge pump is in fluid communication with the geared architecture via a lubrication sump. A non-ferrous chip detector is situated downstream of the geared architecture, but upstream of the scavenge pump. A controller is configured to determine a lubrication condition of the component based on a signal received from the non-ferrous chip detector, and command a status indicator in response thereto.

Abstract: A turbine section including a high pressure turbine, an intermediate pressure turbine and a fan drive turbine, the fan drive turbine driving a gear reduction to in turn drive a fan, and effecting a reduction in the speed of the fan relative to an input speed from the fan drive turbine and said high pressure turbine driving a high pressure compressor, and the intermediate pressure turbine driving a low pressure compressor, with the intermediate pressure turbine having a number of turbine blades in at least one row, and the turbine blades operating at least some of the time at a rotational speed, and the number of turbine blades in the at least one row, and the rotational speed being such that the following formula holds true for the at least one row of the intermediate pressure turbine: (number of blades×speed)/60?5500 Hz.

Abstract: An engine component for a gas turbine engine includes a film-cooled wall having a hot surface facing hot combustion gas and a cooling surface facing a cooling fluid flow. A film hole in the wall has an inlet, an outlet, and a passage connecting the inlet and outlet that defines an inflection point.

Abstract: A gas turbine shroud ring segment assembly (36) with an outer structural block (32A) having cooling channels (72) between inlets (60) on a front face and outlets (74, 76) on a front hanger rail (48). The outlets may be positioned on a radially inner surface (77) of the front rail for impingement and forced convection cooling of backsides of radially inner front lips (44) of adjacent shroud ring segments (30A, 30B) mounted on front and rear rails (48, 50) of the block. The outlets may enter a pocket (86) on the inner surface configured to allow coolant flow in all positions of the ring segments (32A, 32B). The cooling channel may form a main channel (72A) and tributary channels (72B, 72C). These channels may be drilled upward from the rail to the inlet. The tributaries may have offset intersections (72E, 72D) with the main channel.

Abstract: A first stage vane arrangement having an array of first stage vanes and an array of frame segments and method for cooling frame segments of the first vane arrangement of a gas turbine are disclosed. The frame segments are designed for axially receiving aft ends of a combustor transition pieces. The first stage vanes include extended vanes, each vane having a leading section, a trailing edge, and an airfoil extending between an outer platform and an inner platform. The frame segments having an I-beam with an upper horizontal element, a lower horizontal element, and a vertical web. The vertical web having a downstream face facing towards a first stage of a turbine when installed in a gas turbine. The downstream face of the vertical web of at least one of the frame segments overlaps, at least partially, the leading section of at least one of the extended vanes.

Abstract: A bearing assembly is provided. The bearing assembly includes an inner race configured to couple to a shaft, an outer race disposed around the inner race, and a housing disposed around the outer race. The housing and the outer race define an annulus and a buffer region, and the buffer region defines an axial boundary of the annulus.

Abstract: A turbocharger turbine having housing walls defining a diffuser. Within the diffuser, a center body within the diffuser is supported by de-swirl vanes extending from the diffuser wall. The center body forms a de-swirl passageway having an increasing mean diameter of flow from an upstream end of the center body to a leading edge of the de-swirl vanes. A trailing edge of the de-swirl vanes is near the downstream end of the center body. Annular-type guide vanes surround the center body within the de-swirl passageway. A wastegate system is configured to vent wastegate flow into the diffuser through injection ports on the de-swirl vanes, annular guide vanes and/or center body.

Abstract: A method of repairing a casing for a gas turbine engine, wherein the casing has a wall extending generally axially, and between at least one radially extending flange, the radially extending flange being formed with a plurality of bolt holes, includes the steps of removing a portion of the flange including at least one bolt hole. The removed portion is associated with a defect and a remaining portion of the flange includes at least one non-removed bolt hole. A replacement portion is obtained to replace the removed portion. The replacement portion is secured in an opening left in the flange by the removed portion. A repaired gas turbine engine casing is also disclosed.

Abstract: A mid-turbine frame for use in a gas turbine engine comprises at least one vane extending between a vane inner platform and a vane outer platform, and an inner case radially inward of the inner platform. A plurality of tie rods extend from a platform radially inward of the inner case to a radially outer location which is secured by a mount member. The tie rods are secured in the inner case by a forward bolt, and at least one rear bolt, with the forward bolt extending along an axis which is non-parallel to a center axis of the inner case. A gas turbine engine and a method for assembling a mid-turbine frame are also disclosed.

Abstract: A turbine assembly of an engine is disclosed. The turbine assembly includes a nozzle ring for receiving exhaust gases from a combustion chamber having a plurality of guide vanes for guiding the exhaust gases, a stator ring disposed downstream to the nozzle ring, and a rotor disposed circumferentially within the stator ring. The stator ring includes a plurality of stator vanes adapted to receive the exhaust gases through the guide vanes of the nozzle ring. The stator ring is axially movable between a first position and a second position along at least one cross-key pin disposed between the stator ring and a turbine casing. Each of the plurality of stator vanes moves into a throat plane of each pair of the plurality of guide vanes in the first position of the stator ring, and moves out of the throat plane in the second position of the stator ring.

Abstract: This invention relates to a method of condensing and energy recovery within a thermal power plant using the Venturi effect and gas stored under hydrostatic pressure and to an energy storage system using the method in a hydrogen and oxygen combusting turbine, where the hydrogen and oxygen gasses are produced by water electrolysis and hydrostatically pressurized and stored.

Abstract: A liquid heating appliance for heating water or other liquids, suitably to a target temperature of from 55° C. to around boiling point, includes a primary heat chamber or body (heat source chamber) that is thermally insulated and which in use contains a high thermal density heat storing liquid or solid; and a secondary chamber alongside the primary chamber through which a liquid to be heated is passed in use. The appliance has a heat transfer feature to selectively transfer thermal energy from the heat-storing liquid or solid to the liquid to be heated in the secondary chamber. The secondary chamber is preferably a conduit through which the liquid to be heated is able to flow and the thus heated liquid can be delivered to a tap as hot water for a range of uses. Water may also be heated for a central heating system for space heating.

Abstract: In a steam turbine power generation system according to the present invention, a regenerator and an ejector are selectively operated according to outdoor air temperature so that the effects of the outdoor air temperature can be minimized and thus an increase in back pressure of a turbine is prevented and thus the operating efficiency of the steam turbine power generation system can be guaranteed. In addition, when the outdoor air temperature is lower than a set temperature, only a steam condenser and an air cooling condenser are used, and when the outdoor air temperature is equal to or higher than the set temperature, the regenerator and the ejector are operated so that the condensation efficiency of the air cooling condenser is improved and thus the cooling efficiency of the steam turbine power generation system can be maximized.

Abstract: The present application provides a method of evaluating fatigue damage in an actuator spring of a valve used in a turbine by a data acquisition system. The method may include the steps of receiving a number of operating parameters from a number of sensors including valve spindle position over time, determining cyclic loading on the actuator spring based upon the valve spindle position over time, generating an intended design lifetime for the actuator spring, determining a fatigue damage indicator based on the cyclic loading as compared to the intended design lifetime, and altering one or more of the operating parameters and/or initiating repair procedures based upon the fatigue damage indicator.

Abstract: Extra heat in a closed cycle power generation system, such as a reversible closed Brayton cycle system, may be dissipated between discharge and charge cycles. An extra cooling heat exchanger may be added on the discharge cycle and disposed between a cold side heat exchanger and a compressor inlet. Additionally or alternatively, a cold thermal storage medium passing through the cold side heat exchanger may be allowed to heat up to a higher temperature during the discharge cycle than is needed on input to the charge cycle and the excess heat then dissipated to the atmosphere.

Abstract: A heat-driven engine having a first, thermally conductive, pump to which a working medium is admitted and within which the working medium subsequently absorbs its latent heat while undergoing a phase change from low to high enthalpy phase before being expelled from the first pump. Also, a restrictive cooling element accepts the working medium in its high enthalpy phase and allows it to release its latent heat and undergo a phase change from a liquid to a low enthalpy phase. A first and a second passage, through which the working medium traverses, connects the first pump and the cooling element. The second passage incorporates a thermally conductive element, placing the working medium in thermal contact with a heat source or sink. Also, a heat pump is in thermal contact with the first pump and the cooling element. Finally, a power transmission element links the first pump to the heat pump.

Abstract: A method of operating a combined heat and power plant (10) (CHP plant) includes generating hot flue gas and cooling the hot flue gas in a sequence of cooling steps to recover heat and to generate steam in a heat recovery steam generator (16) (HRSG). The HRSG (16) includes an LP steam evaporator (36) designed to generate steam at least over a pressure range of from 2 bar(g) to 18 bar(g) so that either LP steam or MP steam can selectively be generated by the LP steam generator (36), thereby to cool the hot flue gas, and an MP steam superheater (24) upstream of the LP steam evaporator (36) to superheat MP steam in heat exchange with the hot flue gas thereby to cool the hot flue gas.

Abstract: A variable valve mechanism of an internal combustion engine includes a cam, a transmission mechanism, a first variable device that controls the transmission mechanism to continuously change at least a maximum lift amount of a lift curve indicating a lift amount of a valve that corresponds to a rotation angle of the internal combustion engine, and a second variable device that controls the transmission mechanism to continuously change at least an operation angle of the lift curve. When the lift curve lies in any condition within a predetermined range that covers all or part of a variable range of the lift curve, an absolute value of a ratio of a maximum lift amount variation to an operation angle variation for a slight change from the condition caused by the first variable device is larger than that for a slight change from the condition caused by the second variable device.

Abstract: A turbocharged internal combustion engine is provided with at least a partially variable valve train on an intake side wherein the intake valves are controlled to optimize the actuation of a second inlet valve in relation to a first inlet valve for different load conditions.

Abstract: An engine comprising a camshaft, the engine coupleable to an auxiliary device driven from the camshaft, the camshaft comprising: a plurality of valve cams each configured to actuate a respective intake valve or exhaust valve of the engine, an angular orientation of the valve cams about the rotational axis of the camshaft defined by the operational requirements of the valves; and an auxiliary device cam configured to actuate a drive element of the auxiliary device via one or more cam lobes, the auxiliary device cam having an angular orientation about the rotational axis of the camshaft, and the drive element having an angular orientation about the rotational axis of the camshaft, wherein the angular orientation of the drive element of the auxiliary device is selected respective to the angular orientation of the valve cams such that each actuation event of the auxiliary device occurs between two successive valve actuation events.

Abstract: The present invention provides a valve seat of a Co-free, sintered iron-based alloy having excellent heat resistance, oxidation resistance and wear resistance, as well as excellent machinability, which is usable for internal combustion engines using a gas fuel. The valve seat is produced by using a prealloy containing 12% or more by mass of Cr in a matrix for, and hard particles having high strength and hardness at high temperatures are used, such that the entire valve seat has a composition comprising by mass 5.0-20.0% of Cr, 0.4-2.0% of Si, 2.0-6.0% of Ni, 5.0-25.0% of Mo, 0.1-5.0% of W, 0.5-5.0% of V, 1.0% or less of Nb, and 0.5-1.5% of C, the balance being Fe and inevitable impurities.

Abstract: A valve arrangement for a cylinder of an internal combustion engine arrangement includes a check valve configured to be positioned at an intake side port of the cylinder for controlling gas flow into the cylinder, wherein the valve arrangement further includes an intake valve arrangement positioned upstream from the check valve, and an actuating arrangement configured to controllably position the intake valve arrangement for closing the intake side port.

Abstract: A hydraulic fluid system for a variable valve train system is provided that allows hydraulic fluid flow from a high pressure chamber to a medium pressure chamber during a higher pressure phase after a control valve closes. The hydraulic fluid system includes a housing defining (a) the middle pressure chamber which is connected to a hydraulic fluid supply, and (b) the high pressure chamber which contains hydraulic fluid that is pressurized by a pump piston assembly configured to engage a rotating cam. A control valve selectively provides a first flowpath for hydraulic fluid between the middle pressure chamber and the high pressure chamber. A bypass valve selectively provides a second flowpath for hydraulic fluid between the middle pressure chamber and the high pressure chamber based on a pressure of the hydraulic fluid in the high pressure chamber.

Abstract: An internal combustion engine capable of cylinder deactivation or skip fire control in combination with variable valve lift control. One bank of cylinders can be deactivated while the air induction of the other bank of cylinders is regulated using variable valve lift control to increase engine efficiency. An internal combustion engine with two cylinder banks, where control of one cylinder bank using skip fire control can be operating at an appropriate firing fraction in combination with variable valve lift control on the other cylinder bank. A single bank of cylinders can be controlled in a skip fire manner in conjunction with variable valve lift control.

Abstract: An oil supply device for an engine is provided with an oil pump of a variable capacity type; a plurality of hydraulically operated devices connected to the pump via an oil path; a pump control unit which changes the capacity of the pump to control a discharge amount of oil; and a hydraulic pressure detecting unit which detects a hydraulic pressure of the oil path. The plurality of the hydraulically operated devices include a metal bearing, and the pump control unit sets a highest requested hydraulic pressure among requested hydraulic pressures of the hydraulically operated devices as a target hydraulic pressure for each of the operating conditions of the engine, and changes the capacity of the pump in such a manner that the hydraulic pressure detected by the hydraulic pressure detecting unit coincides with the target hydraulic pressure for controlling the discharge amount.

Abstract: The invention relates to a device (11) for cooling oil for a turbine engine, such as an aircraft turbojet or turboprop engine, characterized in that it comprises a duct (12) for circulating a flow of cold air (F1), means (16) for injecting oil into the duct, and means (19) for extracting the oil mixed with the flow of cold air (F1), located in the duct (12), downstream from the injection means (16).

Abstract: An engine control device sets a target value for the engine oil temperature appropriately in an engine that uses gasoline as a fuel, even when the fuel does not have a single boiling point because the gasoline is a mixed composition, or when the fuel property changes (for example, when the vaporization property changes due to deterioration). In other words, the engine control device prevents excessive heating or insufficient heating by changing the oil temperature to the high side in a condition wherein the fuel being used does not easily vaporize, and changing the oil temperature to the low side in a condition wherein the fuel being used easily vaporizes. This engine control device includes an oil temperature controller that controls the temperature of oil lubricating the interior of the engine; a fuel supply device that supplies fuel to the engine; and a detector for detecting the property of the fuel. The temperature of the oil is controlled on the basis of a signal from the detector.

Abstract: A method for operating a combustion engine having a crankcase, a piston group and a crankshaft, wherein the crankcase has an oil reservoir and an operational amount of lubricating oil is provided, wherein i) a partial amount of the lubricating oil is continuously discharged from the crankshaft and ii) a refill amount of new lubricating oil is continuously supplied, so that the operational amount of lubricating oil remains essentially the same; as well as a combustion engine for carrying out the method.

Abstract: A device for cleaning a contaminated crankcase gas generated during operation of an internal combustion engine is provided. An internal combustion engine including such a device is also provided. The device permits for an increased flexibility as to constructing the cleaning device while maintaining or possibly improving cleaning of the contaminated crankcase gas.

Abstract: A clean-side oil and air separator includes (i) a first housing including a filter material; (ii) a second housing including a threaded portion adapted to be a direct replacement for an engine oil fill cap removably closing an oil engine fill port; and (iii) a coupler disposed between and removably coupling the first housing and the second housing; wherein the first housing, second housing, and coupler include a continuous fluid pathway therethrough that extends between (a) an air intake from a PCV valve and (b) the engine oil fill port; and wherein the filter material is disposed in said fluid pathway within said first housing.

Abstract: Provided is an exhaust gas purification filter including a substrate comprising a plurality of porous partitions, wherein the partitions form an exhaust gas flow path, a porous catalytic layer is provided on the partitions and the catalytic layer having a thickness of 10 ?m or greater is provided over at least 20% of the total length of the partitions in the lengthwise direction thereof, and the catalytic layer having a thickness of 10 ?m or greater is not present on the partitions 15 mm from an outflow side.

Abstract: A particulate filter (1) is provided having a first wall flow region (2) and a second flow through region (3). The filter is provided with a catalytic washcoat, whereby the filter can be used to remove both particulate matter and harmful gaseous emissions from an exhaust gas stream.

Abstract: A first fuel addition valve disposed in a portion of a first exhaust passage upstream from a first upstream purification device, a first urea addition valve disposed in a portion of the first exhaust passage between the first upstream purification device and a first downstream purification device, and a first valve cooling passage configured such that i) refrigerant passes the first urea addition valve and the first fuel addition valve in order, and ii) the refrigerant cools the first fuel addition valve after the refrigerant cools the first urea addition valve.

Abstract: An exhaust system for an internal combustion engine, the exhaust system comprising, a lean NOx trap, a NOx storage and reduction zone on a wall flow monolithic substrate having a pre-coated porosity of 50% or greater, the NOx storage and reduction zone comprising a platinum group metal loaded on one or more first support, the or each first support comprising one or more alkaline earth metal compound, and a selective catalytic reduction zone on a monolithic substrate, the selective catalytic reduction zone comprising copper or iron loaded on a second support, the second support comprising a molecular sieve.

Abstract: Provided is an exhaust purification system including: an NOx occlusion reduction type catalyst (32), a catalyst temperature estimating unit (115), an NOx occlusion amount estimating unit (113), a regeneration control unit (100) that performs catalyst regeneration of bringing an exhaust gas into a rich state to recover NOx occlusion capacity of the NOx occlusion reduction type catalyst (32), an interval setting unit (118) that sets a target interval from the termination of the catalyst regeneration to a start of next catalyst regeneration, a catalyst regeneration start processing unit (110) that starts the next catalyst regeneration when the NOx occlusion amount is equal to or greater than a threshold and an elapsed time from the termination of the catalyst regeneration reaches the target interval, and an interval target value correcting unit (119) that extends and corrects the target interval based on the NOx occlusion amount when the catalyst temperature is lower than a predetermined catalyst activation temp