Abstract: The invention is a bearing unit and bearing system for supporting a large rotatable element, such as a mooring turret. The bearing unit includes a hydrostatic suspension system which enables the bearing unit to accommodate fabrication tolerances and also enables the bearing unit to conform to relative movements between the ship and the turret, thereby providing a compliant bearing system. The system includes multiple bearing units of the invention which serve as thrust and/or radial bearings for supporting the turret. By manifolding a plurality of bearing units together in a fluidly-isolated group, the pressure applied to the bearing units in that group is self-equalizing so that all the bearing units act in unison to equally support the load, while also allowing some degree of self-alignment and tilting of the load. As a result, the bearing system emulates a self-aligning bearing system and is able to compensate for axial and angular misalignment.

Abstract: A detachable handle system (10) includes a connector which in a first embodiment (33) pins (34) to a handle tube (21), and which in a second embodiment (433) attaches through a resilient tube (437) that is radially expanded. The detachable handle is in the preferred embodiment provided with a readily replaced handle grip (22). By detaching the handle (21) and replacing the handle grip (22), a multitude of grips may be fabricated in diverse colors and geometries for a single handle, thereby satisfying the desires of each individual user. A tow rope (35) is attached to the connector (33, 433) through a hole (36) in the connector (33) and then circumferentially about the connector (33), independent of the handle tube (21).

Abstract: A high efficiency extremely stable marine vehicle that is connected to and supported by submerged supporting structure(s) is presented. The submerged structure(s) are normally airfoil shaped to insure maximum efficiency and are, in the preferred embodiments, air lubricated on their undersides by pressurized air to reduce wetted area frictional effects. Propulsor(s) take in water from the boundary layer adjacent the upper surfaces of the submerged supporting structure(s) which provides boundary layer control and also enhances the efficiency of the propulsor(s).

Abstract: A side stop arm for school buses in various embodiments, each embodiment having the common element of an extendable arm on the side of a bus that contains the STOP sign or moves in concert with the arm. The extendable arm acts as both a deterrent to vehicles that may wish to pass the bus on the driver's side but more importantly acts as warning as to the bus being stopped for loading or discharge of passengers. The first extendable arm is a separate element engaged to the side of the bus. In this embodiment, the extendable arm has a breakaway portion in the event a passing vehicle comes into contact with the arm. In a second embodiment of the invention, the STOP sign is engaged to the end of the extendable arm and it extends outwards with the arm to a position displaced from the side of the bus. In a third embodiment, that is a combination of the first two, the STOP sign is engaged to the end of a first extendable arm that moves in conjunction with a second extendable arm.

Abstract: A test system and a method for producing a test signal for food tolerance analysis using a signal producing device (12), from which an electric signal may be produced at a defined frequency spectrum and may be electrically coupled with a sample (18) containing at least one sample substance, and with an output (23), via which the signal generated by the signal producing device (12) may be emitted when coupled electrically with the sample (18). The test system and method enable food tolerance analysis to be performed easily, safely and quickly.

Abstract: An apparatus for growing a single crystal (20) comprising at least a main chamber (1) enclosing a crucible (5, 6) for accommodating a raw material melt (4) and a heater (7) for heating the raw material melt and a pulling chamber (2) continuously provided above the main chamber, into which a grown single crystal is pulled and stored, wherein the apparatus further comprises a cooling cylinder (11) that extends at least from a ceiling of the main chamber toward a raw material melt surface so as to surround a single crystal under pulling (3) and is forcibly cooled with a cooling medium, and an auxiliary cooling member (13) extending below the cooling cylinder and having a cylindrical shape or a shape tapered toward the downward direction. There is provided an apparatus for growing a single crystal that can exert cooling effect on a grown single crystal to the maximum extent so as to accelerate the crystal growth rate and safely produce a single crystal without leakage of cooling medium due to breakage etc.

Abstract: A method for making a below 200-nm wavelength optical fluoride crystal feedstock includes loading a fluoride raw material into a chamber, exposing the fluoride raw material to a flow of gaseous fluoride at a predetermined temperature, and storing the exposed fluoride raw material in a dry atmosphere.

Abstract: Disclosed is a method for producing a Group III nitride compound semiconductor including a pit formation step in which a portion of an uppermost layer of a first Group III nitride compound semiconductor layer containing one or more sub-layers, the portion containing lattice defects, is subjected to treatment by use of a solution or vapor which corrodes the portion more easily than it corrodes a portion of the uppermost layer containing no lattice defects, the first Group III nitride compound semiconductor layer not being accompanied by a substrate therefor as a result of removal therefrom, or being accompanied by a substrate such that the semiconductor layer is formed with or without intervention of a buffer layer provided on the substrate; and a lateral growth step of growing a second Group III nitride compound semiconductor layer through vertical and lateral epitaxial overgrowth around nuclei as seeds for crystal growth which are on flat portions of the uppermost layer of the first Group III nitride compoun

Abstract: A method, installation and reactor is for the production of components or of their intermediate products. Each component in the process of being produced as a structural member, is subjected to a treatment process and several of the structural members are simultaneously subjected to a common CVD process under conditions of ultrahigh vacuum. The treatment process is a vacuum process and from it the structural members are supplied to the CVD process under vacuum.

Abstract: An apparatus and process for atomic layer deposition that minimizes mixing of the chemicals and reactive gases is disclosed. The first precursor and second precursor are only mixed with other chemicals and reactive gases when and where desired by installing and monitoring a dispensing fore-line. Also, independent and dedicated chamber outlets, isolation valves, exhaust fore-lines, and exhaust pumps are provided that are activated for the specific gas when needed.

Abstract: The invention relates to a method and a device for producing Group-III-N, Group-III-V-N and metal-nitrogen component structures on Si substrates by means of organometallic gas phase epitaxy.

Abstract: A refined SiC single crystal that includes a small number of defects is provided as follows. At a first growth step, a first seed crystal is formed from a crude SiC single crystal, and a first grown crystal is formed on a first growth surface, which is a plane having an inclination of 20 degrees or smaller from a {1-100} plane or an inclination of 20 degrees or smaller from a {11-20} plane. At an intermediate growth step, an n growth crystal is formed on an n growth surface, which is a plane having an inclination of 45 to 90 degrees from an (n−1) growth surface and an inclination of 60 to 90 degrees from a {0001} plane. At a final growth step, a final SiC single crystal is formed on a final growth surface, which has an inclination of 20 degrees or smaller from a {0001} plane.

Abstract: A susceptor for use in a Czochralski crystal growing apparatus is disclosed wherein erosion of the susceptor is minimized. The susceptor contains ventilation holes that allow process gases found between the susceptor and crucible to escape. The crucible may incorporate the use of a protective coating over part or all of the susceptor, such as a silicon carbide coating. The ventilation holes are placed at various heights along the susceptor wall to allow ventilation near the area of plastic deformation of the crucible.

Abstract: Decrease in sensitivity can be avoided to obtain a stable and highly sensitized photosensitive layer in a process for preparing a photopolymerizing lithographic plate including a coating step and using rubber rollers before and after the coating site. This is achieved by excluding an antioxidant and/or aging retardant from at least the surface of rubber rollers placed before and after the coating site. The photopolymerizing lithographic plate excellent in its sensitivity as compared with the conventional one can be obtained.

Abstract: A coating tool and a coating set including such a coating tool can uniformly and reliably apply protection liquid onto the recording surface of a recording medium so as to avoid problems of uneven application and uncoated areas. The coating tool comprises a protection liquid absorbing member for absorbing and holding protection liquid. The protection liquid absorbing member is formed to show a density not less than 30 kg/m3.

Abstract: An apparatus (1) for applying a slurry to a substrate (2). The apparatus includes a delivery drum (4) incorporating a delivery surface (5) disposed to support a layer of slurry. A spattering roller (8) is positioned closely adjacent the delivery drum and is rotatable so as to spatter the slurry from the delivery surface onto the substrate. Regulation means selectively vary or interrupt the flow of slurry from the delivery surface onto the substrate.

Abstract: An apparatus and method for holding a substrate on a support layer in a processing chamber. The method includes the steps of positioning the substrate a predetermined distance from the support layer, introducing a plasma in the processing chamber, lowering the substrate to a point where the substrate engages the support layer, and maintaining the plasma for a predetermined time. The apparatus is directed to a susceptor system for a processing chamber in which a substrate is electrostatically held essentially flat. The apparatus includes a substrate support and a support layer composed of a dielectric material disposed on the substrate support. At least one lift pin is used for supporting the substrate relative to the support layer. Means are provided for moving each lift pin relative to the support layer. Means are also provided for producing a plasma within the processing chamber.

Abstract: Disclosed are an apparatus for and a process of atomic layer deposition using remote plasma. A thin film is deposited to a desired thickness on a wafer by use of the apparatus, which comprises a plurality of transfer pipes for individually transferring the first and the second reactive gas and the carrier gas to the vacuum chamber; an energy supplier, provided inside the transfer pipe for transferring the first and the second reactive gas, for supplying excitation energy to generate excited plasma to ionize the first reactive gas; and a valve controller, established in the transfer pipes, for alternately feeding into the vacuum chamber the second reactive gas and the first reactive gas ionized by the plasma excited in the energy supplier, at predetermined time intervals.

Abstract: An apparatus and process for atomic layer deposition that minimizes mixing of the chemicals and reactive gases is disclosed. The first precursor and second precursor are only mixed with other chemicals and reactive gases when and where desired by installing and monitoring a dispensing fore-line. Also, independent and dedicated chamber outlets, isolation valves, exhaust fore-lines, and exhaust pumps are provided that are activated for the specific gas when needed.

Abstract: A method is provided for preparing a substrate for processing in a chamber that has a substrate receiving portion. The substrate is positioned within the chamber in a location not on the substrate receiving portion. A gaseous flow is provided to the chamber, from which a plasma is struck to heat the substrate. After the substrate has been heated, it is moved to the substrate receiving portion for processing.

Abstract: A tunable multi-zone injection system for a plasma processing system for plasma processing of substrates such as semiconductor wafers. The system includes a plasma processing chamber, a substrate support for supporting a substrate within the processing chamber, a dielectric member having an interior surface facing the substrate support, the dielectric member forming a wall of the processing chamber, a gas injector fixed to part of or removably mounted in an opening in the dielectric window, the gas injector including a plurality of gas outlets supplying process gas at adjustable flow rates to multiple zones of the chamber, and an RF energy source such as a planar or non-planar spiral coil which inductively couples RF energy through the dielectric member and into the chamber to energize the process gas into a plasma state.

Abstract: An apparatus for producing a foam surfactant suitable for a bovine teat dip comprises means for air pressurization of a surfactant solution containing a germicide, disinfectant, biocide, etc., means for passing the air-surfactant mixture through a flow or line mixer to a foam holding cup adjacent the teat area and means for expanding the mixture in the holding cup to produce an adherent surfactant foam product with reduced run off, which both protects and reduces infection of the teat and surrounding udder area.

Abstract: An animal feeder system comprises a mobile feeder suspended from an overhead track. The track can conveniently be made from pipe bent into a desired configuration. The mobile feeder has an on-board computer controller and a computer-controlled motor which can drive the mobile feeder to feed drops located along the track. The mobile feeder has a number of feed compartments which each hold a feed ingredient. The ingredients are dispensed simultaneously by variable speed augers. A customized blend of feed ingredients is dispensed at each feed drop. The animal feeder system can automatically track the amount of feed consumed at each feed drop and can run unattended. Applications include feeding swine, horses, chickens, fish, cattle and other animals which are reared in captivity.

Abstract: A new use of coconut coir includes using the coir as an absorbent in pet litter. The coconut coir can be used alone as a kitty litter or other pet litter, in combination with fragrance, or in combination with other absorbents such as clay, gypsum, diatomaceous earth, alfalfa, wood chips, sawdust, paper, foam, plastic or other similar absorbent material.

Abstract: The present invention relates to a recirculating marine aquaculture process for production of a crab species, including (i) a broodstock conditioning, (ii) spawning, (iii) egg incubation, (iv) larval growth, (v) nursery post-larval growth, and (vi) grow-out of the crab to a final product weight, in which each stage (i)-(vi) of the process involves operation in an aqueous medium that is coupled in liquid recirculation relationship with means for removing waste components from the aqueous medium and returning purified aqueous medium to the external environment. The process involves operation in a closed, recirculating aquaculture system in which photoperiod, water temperature, water chemistry, and diet are optimized and then continuously monitored and controlled to obtain optimal production at each of the six phases (i)-(vi) of the life cycle.

Abstract: A double lead leash construction (10) including a pair of generally elongated lead members (20), (20′) having looped distal ends (21) engaging a respective pair of snap swivels (22), (22′). The proximal ends of the lead members (20), (20′) are joined together as at (23). A rigid support arm (30) connected on its opposite ends to opposed surfaces of the lead members (20), (20′) proximate to, but spaced from the juncture (23) of the lead member s (20), (20′) and a generally rigid main shaft member (60) having a distal end attached to the juncture (23) of the lead members (20), (20′) and a looped proximal end (61) that captively engages a double swivel element (62) that is adapted to be attached to a conventional control handle unit (14), (14′) to prevent the entanglement of the pair of lead members (20), (20′) while walking a pair of animals.

Abstract: An animal mask for removable fitment to the appropriate portion of the head of an animal such as the front of the head or over one nostril for the effective delivery of drugs or medicaments, for pulmonary or nasal absorption. The rings of the mask are nestable, forming a succession of monotonically decreasing sized telescopable rings from a largest ring to a smallest ring to form a relatively flexible skirt. An animal interface adapter extends from the largest ring and is adapted to establish a substantial seal between the animal interface adapter and the face of an animal. The animal mask is collapsible to permit use in a full or partially open state, and to permit easy and convenient transport in a collapsed or closed state.

Abstract: An indirect black liquor concentrator uses recirculating flow black liquor through a heat exchangers, employing flue gas for heat. The heated liquor is flashed, to provide steam and concentrate the liquor.

Abstract: A hot water heating system, and kit for installing such a system, that utilizes male and female union connections for all main heating system components allows the system to be completely installed using only two ordinary wrenches. The system includes a first isolator valve, a flow control valve, a circulator and a second isolator valve. Each of these components is equipped with one male union type connection on one side of the component and one female union type connection on the other side. The system may be an installed system or may entail a kit of parts for installation.

Abstract: A water lance blower for cleaning heat installations is disclosed. A water lance linked with a water feed conduit system is swivel-mounted with its orifice disposed in a hatch. The water lance can blow a jet of water through the heating installation in operation and through which flames and/or flue gases are guided to wall areas that can be reached from the hatch. The water lance blower is provided with a drive system with at least two drive units that control the water lance, and with a holding device that fastens the water lance blower onto the heating installation. Further, parts of the water feed conduit system are integrated onto the holding device, thereby substantially limiting the size of the water lance blower to the swivel range of the water lance.

Abstract: A device for liquefying fuel fractions which are in vapour form in fuel tanks (1), having a suction device (10), a pump (13), a condensation device (16) and a separation and storage device (18). This device has a regulation means, with the aid of which the fraction-air mixture (31), which is displaced by the fuel (30), flowing in during the refuelling of the fuel tank (1) and/or a fraction-air mixture (31) which is produced by air injection by means of an air-injection device (23) can be sucked out and separated.

Abstract: An electronic control unit for a combustion engine having a water coolant passageway in heat transfer adjacency to the unit and adapted to remove heat from the unit. An ECU for combustion engine, comprising: electrical input circuits, electrical control circuits, electrical fuel injection output drive circuits, electrical oil pump output drive circuits and electrical ignition circuits. An ECU is disclosed which is adapted to verify firing of the ignition coils of the engine.

Abstract: A spark-ignition rotary internal-combustion engine, having a plurality of pistons (7) which perform a reciprocating motion inside cylinders (6) arranged so as to be equally angularly spaced on a same circumference, the cylinders (6) being formed in a rotating body or rotor (2) which rotates coaxially inside a fixed body or stator (1), in which the inlet duct (9) for the air-fuel mix, the burnt gas exhaust duct (8) and the spark-plug recess (10) are provided.

Abstract: An axial piston rotary power device has a housing enclosing a cylindrical chamber. An axially undulating guide cam is medially fixed to the inner annular wall of the chamber. A central cylindrical stator protrudes axially through the chamber from one end of the housing. The stator has lateral intake and discharge ports communicating with axial channels for conveying working fluid to and from the chamber. A rotary cylindrical block has a plurality of closed-ended cylindrical bores parallel to and spaced apart at equal angular intervals around a central bore. The block rotatably encloses the central cylindrical stator. Each closed-ended cylindrical bore has, at each end, a radially inward opening through the central bore and axially aligned with lateral ports in the central stator. A plurality of double-acting pistons are slidably received in the bores. Each piston has a medial stub shaft protruding through a slot parallel to the axis.

Abstract: An axial piston rotary power device can be configured as a four-cycle and two-cycle internal combustion engine, a compressor, a pump, a fluid-driven motor or an expander. The device includes an external stator housing, an internal axial stator and a rotary cylindrical block attached to an end shaft that can rotate within the annular enclosure formed by the two stators. The cylindrical block contains a plurality of cylindrical cavities arranged as pairs of working cylinders. Each cylindrical cavity encloses a double-acting piston assembly comprising two piston heads connected to a middle portion having a pair of axially spaced apart roller cam followers that make roller contact with a guide cam surface protruding from the inside of the external stator housing. The action of the cam roller followers on the guide cam imparts rotation to the cylindrical block when the piston assemblies reciprocate within their respective bores.

Abstract: A four stroke engine including a crankshaft. A power piston within a first cylinder connected to the crankshaft such that the power piston reciprocates through a power stroke and an exhaust stroke. A compression piston within a second cylinder is connected to the crankshaft such that the compression piston reciprocates through an intake stroke and a compression stroke. A gas passage interconnects the first and second cylinders and includes an inlet valve and an outlet valve defining a pressure chamber therebetween. An inlet manifold is in fluid communication with an inlet valve of the second cylinder. A bypass valve is in fluid communication with the second cylinder and the inlet manifold, wherein during a compression stroke the bypass valve allows a portion of the air to bypass the inlet valve and exhaust into the inlet manifold to provide a variable compression ratio.

Abstract: In an internal combustion engine with a motor block (6) and a longitudinal extending anti-rotation guide (5), which includes receiving recesses situated at apportioned spatial distances, one from the other to receive valve tappets and is affixed in a receiving groove of the motor block (6). The guide (5) is constructed as an injection molded component with a one-piece, molded-on, elastically expanded or deformable clip, which engages in a complementary receiving contour on the motor block (6).

Abstract: A valve timing control device for an internal combustion engine, in which upon cold start, combustion gas containing quench hydrocarbons and wet fuel is confined in a combustion chamber by advancing an exhaust valve close timing. This combustion gas is richer in hydrocarbons and wet fuel than is the gas produced after the engine has been warmed up. When the pressure in an intake line becomes lower than 600 mmHg, the exhaust valve close timing is retarded so as to recirculate post-combustion gas back to the combustion chamber. Then the unburned hydrocarbons in the post-combustion gas are involved in combustion again and their emission is reduced. Such gas recirculation and confinement to the combustion chamber are switched in accordance with a target valve underlap corresponding to the intake line pressure in the internal combustion engine.

Abstract: A valve timing control device according to the present invention has a between-sealing-faces clearance defined between a frontal end of each shoe of a first rotor and an outer periphery of a boss section of a second rotor corresponding to the frontal end of the shoe and accepting the quantity of oil leaks having no effect on the responsibility of the device as a maximum value. The between-sealing-faces clearance is so set as to be larger than the maximum bearing clearance defined between the camshaft and a bearing section of the device supporting rotationally the camshaft.

Abstract: A device for changing the control times of gas exchange valves of an internal combustion engine, particularly a rotary piston adjusting device for rotation angle adjustment of a camshaft relative to a crankshaft, which device is fastened by a central fastening screw to a camshaft mounted in the cylinder head of the internal combustion engine. The device includes a stator, in driving connection with the crankshaft and having two side covers, and of a rotor connected to rotate with the camshaft, with at least two hydraulic working spaces being formed in the stator by at least two radial boundary walls. The chambers are divided by at least two radial vanes on the rotor, respectively, into two hydraulic pressure chambers which work in opposition to one another. The stator and the one side cover of the device are formed as an integral stator unit, and the rotor and the other side cover are formed as an integral rotor unit.

Abstract: A valve timing control apparatus is provided which comprises an intermediate rotary member rotatable relative to a driving rotary member and a driven rotary member and having a spiral guide of a single spiral. Rotation of the intermediate rotary member caused by a control force applying unit causes radial movement of the guided members which is in turn converted to relative rotation between the driving rotary member and the driven rotary member by the links. The spiral of the spiral guide is defined so that a rate of change of spiral radius per angle is not constant.

Abstract: A first stopper device is arranged between an output element of a planetary gear unit and a drive rotation member driven by an output shaft of an engine. The first stopper device stops a relative rotation therebetween when a relative rotation angle therebetween comes to a first predetermined degree. A second stopper device may be arranged between a free element of the planetary gear unit and an input element of the planetary gear unit. The second stopper device stops a relative rotation therebetween when a relative rotation angle therebetween comes to a second predetermined degree.

Abstract: In a valve timing control system, an intermediate rotator is rotated with respect to a driving plate and a lever shaft to make radial displacement of a ball engaged with a spiral slot of the intermediate rotator along a radial slot. The radial displacement is converted into relative rotation of the driving plate and the lever shaft through a link. A bottomed cylindrical guide member which is rotatably supported by a front end of the link has a base engaged with the spiral slot. The ball engaged with the spiral slot, a retainer for supporting the back of the ball, and a coil spring for biasing the ball through the retainer are accommodated in a hold hole of the guide member. Disengagement of the ball from the spiral slot is prevented by an abutment of an end face of the retainer and a bottom wall of the hold hole.

Abstract: A valve timing control apparatus including a drive rotary member, a driven rotary member and an intermediate rotary member rotatable relative to the drive and driven rotary members. A follower is moveably engaged with a radial guide of one of the drive and driven rotary members and a spiral guide of the intermediate rotary member. An actuator rotates the intermediate rotary member to allow a movement of the follower along the radial guide which is converted into relative rotation of the drive and driven rotary members via a link coupling the follower with the other of the drive and driven rotary members. A lubricating oil chamber is arranged to surround an engagement portion between the spiral guide and the follower and pivotal connection portions between one end of the link and the other of the drive and driven rotary members and between an opposite end thereof and the follower.

Abstract: An internal combustion engine having at least one combustion cylinder that includes a combustion chamber provided with gas-exchange valves, and an electrohydraulic valve control device having valve actuators that actuate the gas-exchange valves. To reduce manufacturing costs and/or the installation space required for the electrohydraulic valve control device, at least two synchronously controlled gas-exchange valves are connected using a coupling element to a common valve actuator, and the connection sites of the gas-exchange valves are flexibly formed on the coupling element.

Abstract: Simplifying a control system by integrating current control for an exciting coil and a main current control for a starter motor is accomplished by a current control unit for a starter motor and is constructed with a control device provided among a battery, a motor contact point and an exciting coil, and a starter ECU for driving the control device. The control device has a device capacity for allowing main current of the starter motor. The starter ECU changes a control specification for the control device before and after closing the motor contact point. That is, control-start timing of a coil current is determined by a battery voltage before closing the motor contact point. Thereafter, the coil current is restricted to a predetermined value to reduce a moving speed of a plunger. After closing the motor contact point, the main current is slowly raised.

Abstract: An intake system of an engine comprises an intake module, in which a throttle body joint portion and an upstream portion of an intake manifold are formed in a single structure, and a downstream portion of the intake manifold extending from an engine body. A downstream end of the intake module is joined to the downstream portion of the intake manifold and an end portion of the intake module opposite to its portion joined to the downstream portion of the intake manifold is connected to an uppermost part of an oil filler pipe which is connected to the engine body. In this construction, the intake module is supported by the engine body via the oil filler pipe.

Abstract: A cuff is clamped to a boss on an air resonator. The cuff has an inner leg with an o-ring seal sized to provide a seal against an inner periphery of the air resonator boss. A throttle body has a boss to be received within the inner leg of the cuff, and will also deform the o-ring seal. The inner leg preferably includes a second forward seal which also contacts the throttle body boss. Preferably, this second seal includes a spring for biasing the second seal against the throttle body boss. The cuff is initially placed on the air resonator which may then be mounted within the engine compartment. The throttle body may be then simply snapped into the cuff. In this way, no space around the connection is necessary, while a dust-free connection is still provided.

Abstract: This is a high torque power reciprocating engine. Comprehensive mathematics shows its fuel efficiency and why it is inherently impossible to make crank engines efficient.

Abstract: An engine for a motorcycle having dummy covers for covering at least part of cylinder heads from the sides and overhead covers for covering at least part of head covers coupled to the cylinder heads from above and the sides. This configuration is provided in order to enhance the functional beauty of the engine wand to eliminate the need to provide specially shaped parts for cylinder heads, or the need provide a special surface treatment for the cylinder heads. At least one spot of dummy covers is fastened to an engine main unit including a cylinder head and a head cover with bolts. A plurality of engaging protrusions provided in overhead covers formed in a shape to cover the bolts are resiliently engaged with the engine main unit or the dummy covers so that the overhead covers are detachable or attachable.