Abstract: A method of mounting an accelerometer to an internal combustion engine comprises securing the accelerometer to a mating surface on an engine component external to a combustion chamber where the accelerometer can generate a signal output that is characteristic of engine knock, when it occurs, and at least one other combustion behavior inside the combustion chamber during a combustion event. The method further comprises connecting a signal wire at one end to the accelerometer and at an opposite end to a signal processor, and increasing the signal output's signal-to-noise ratio.

Abstract: An engine control device with a reverse control function including: reverse control means for performing reverse control including a process of excessively advancing an ignition position of an engine for reversing a rotational direction of the engine when a reverse switch is operated; and a light emitting display device that displays that the reverse control is performed, wherein the reverse control means further includes light emitting display device blinking means for blinking the light emitting display device when the reverse switch is once operated, and operating error preventing means for starting the reverse control when the reverse switch is again operated within a set time after the one operation of the reverse switch, and stopping the reverse control when the reverse switch is not again operated within the set time after the one operation of the reverse switch.

Abstract: In a fuel supply system for a spark-ignition internal combustion engine having a blow-in valve for each cylinder for blowing an easily ignitable mixture of a liquid fuel and a combustion gas via a blow-in nozzle into a combustion chamber of the internal combustion engine, the blow-in valve has a pressure connection for supplying pressurized combustion gas to a blow-in nozzle from an external pressure source and the blow-in valve has a piston/cylinder unit for delivering the liquid fuel for injection into the cylinder together with the combustion gas with a plunger of being provided for an at least indirect actuation of a nozzle needle of the blow-in nozzle controlling the injection of a metered quantity of fuel and the combustion gas.

Abstract: In a method for operating an internal combustion engine including inlet valves with variably adjustable opening curves, during part-load operation, the closing time of the inlet valves and the fuel injection time are controlled as a function of the cylinder internal temperature so as to maintain the cylinder internal temperature relatively low in a controllable manner for reducing NOx emissions.

Abstract: An estimated quantity of soot deposited near a movable part of a variable capacity mechanism and an estimated quantity of soot burnt off therefrom are determined in advance in accordance with values of parameters (engine rotation speed or similar) that express the engine operating condition, and stored in storage means. Then actual values of the parameter are measured, and an estimated deposition quantity Sa and an estimated burn off quantity Sb corresponding to the measured values are determined from the storage means. An estimated remaining quantity of soot Kn is determined by obtaining the difference between the estimated deposition quantity and the estimated burn off quantity, and a movable vane is forcibly driven to open and close in accordance with the estimated remaining quantity Kn.

Abstract: The present invention relates to a rotary motor, preferably a pivot drive for construction machinery, trucks and the like comprising an elongate housing, preferably an approximately tubular housing, a piston displaceably received in the housing, which is axially displaceable by charging with a pressure medium in a pressure chamber, and a shaft received axially fixedly, but rotatably in the housing, with the piston being in screw engagement with the shaft and/or the housing. The invention furthermore relates to a method for the manufacture of such a rotary motor. The present invention departs from the previous approach of separating the sealing of the piston at the shaft and at the housing from the section effecting the rotary guide or the screw engagement.

Abstract: In the seal structure (30) of a fuel injection valve, including an annular seal member (31) which effects sealing in order that high-pressure fuel within a pressure-introducing chamber (21) may not escape onto a low-pressure side through a gap (28) that is defined between an injector housing (2) and a valve body 6 having a valve piston (5) slidably inserted, and which is disposed in the pressure-introducing chamber (21); a backup ring (32) having a rigidity is arranged between the gap (28) and the seal member (31), so as to prevent the seal member (31) from being pushed out into the gap (28), and the backup ring (32) is provided with a plurality of pawls (33), by which the seal member (31) is fixed to the backup ring (32), thereby to prevent the seal member (31) from floating.

Abstract: An injection system for injecting one or both of water and alcohol into an internal combustion engine comprising a system monitor, a control module and a mixture delivery system. The system monitor may have a parameter level display, the control module may be adapted to receive one or more user-supplied parameters and the control module may be further adapted to store the one or more user-supplied parameters. The control module may also be comprised of a plurality of connectors and at least one electrical signal generator. The system may also be comprised of electrical wiring and a mixture delivery system having a pressure source.

Abstract: A fuel injector, e.g., for fuel-injection systems of internal combustion engines in motor vehicles, includes a valve housing including a sleeve-shaped housing section; and a solenoid, situated on the housing section, having a coil brace, magnetic coil and magnetic cup. To protect the magnetic coil from salt fog that arises under specific environmental conditions and penetrates along the contact areas of solenoid and housing section, the coil brace with wound magnetic coil is completely enclosed on all sides by a one-piece plastic coat.

Abstract: A control method for an actuator (1-4) of an injector of a fuel injection system in an internal combustion engine has the following steps: specification of a target value (SOISOLL) for the start of the injection; electric control of the actuator (1-4) at a specific trigger time (tTRIGGER) with a specific actuator energy (E); detection of an actual value (SOI1IST, SOI2 IST, SOI3 IST, SOI4 IST) at the start of the injection; determination of the deviation between the target and actual values (DeltaSOI1, DeltaSOI2, DeltaSOI3, DeltaSOI4) at the start of the injection; and adjustment of the actuator energy (E) in accordance with the deviation between the target and actual values (DeltaSOI1, DeltaSOI2, DeltaSOI3, DeltaSOI4) at the start of the injection to control the start of the injection.

Abstract: An apparatus for controlling the quantity of fuel injection of injectors in accordance with the fuel pressure in the fuel rail of a direct injection type internal combustion engine, including a fuel injection quantity calculating section for calculating the quantity of fuel injection of the injector, a fuel discharge quantity calculating unit for calculating the quantity of fuel discharged from the high-pressure fuel pump into the fuel rail, and a difference calculating unit for calculating the difference between the quantity of fuel injected out of the injector calculated by the fuel injection quantity calculating section and the quantity of fuel discharged from the high-pressure fuel pump into the fuel rail calculated by the fuel discharge quantity calculating unit, wherein the reference value for controlling the injector is obtained on the basis of the difference and the fuel pressure in the fuel rail at the time of starting fuel injection out of injector, and the injector is controlled depending on the re

Abstract: A system and method are provided for determining an ethanol content of a fuel that is part of a fuel and air mixture combusted within an internal combustion engine. A pressure characteristic of a fuel rail is monitored during operation of the engine. At least one of an effective bulk modulus of the fuel and a pressure perturbation signature is determined based on the pressure characteristic. The ethanol content is determined based on the at least one of the effective bulk modulus and the pressure perturbation signature.

Abstract: A vehicle fuel tank assembly includes a fuel tank having a fuel pump receiving opening, a fuel pump, a mounting ring, at least one attachment member (a clip) and a fuel pump cover. The fuel pump is disposed in the fuel pump receiving opening such that a portion of the fuel pump is exposed. The mounting ring secures the fuel pump to the fuel tank. The at least one attachment member has a ring attachment portion connected to the mounting ring and a cover attachment portion. The fuel pump cover is connected to the cover attachment portion of the attachment member to substantially cover at least the exposed portion of the fuel pump.

Abstract: A fuel system of an engine is provided with a venting assembly to vent air that accumulates within a fuel filter of the fuel system and provides anti-drainback of clean fuel back toward the fuel filter when the engine is turned off. In one embodiment, the venting assembly includes a piston valve that provides both the vent and anti-drainback. The valve is actuatable by fluid pressure to a first position that restricts drainback, a second position that restricts venting, and intermediate positions between the first and second positions which permit venting.

Abstract: A method of controlling an internal combustion engine having a fuel vapor purging system and a fuel delivery system including a fuel pump and a fuel pressure sensor for detecting the fuel pressure provided by the fuel pump is disclosed. In one example, the method includes, during a degraded condition of the fuel pressure sensor, adjusting the fuel pump output in response to an operating condition, adjusting at least one of a condition of the fuel vapor purging system and adaptive learning of a characteristic of the fuel delivery system; and further adjusting the fuel pump output in response to an output of an exhaust gas sensor while also adjusting an amount of fuel injected into a cylinder of the engine in response to said output of the exhaust gas sensor.

Abstract: A method of carboration and combustion where a combustible gas is mixed and burned in a compression combustion engine yielding power and no hydro carbons. Where a certain H2 gas derivative is mixed with other gases and burned. And where the gas entering the combustion area is controlled by varing the pressure and thus the power output.

Abstract: A V-twin engine having a crankcase and a pair of cylinders defining a V-space therebetween, wherein the V-space is substantially enclosed, and a carburetor is positioned within the V-space. An intake air preheating arrangement supplies heated intake air to the carburetor, and a carburetor heating arrangement heats the V-space and the carburetor which is positioned within the V-space. Each of the foregoing arrangements, used separately or in combination within one another, aids in preventing “freeze-up” of the carburetor during running of the engine in a cold environment.

Abstract: A method of operating an engine having at least one cylinder, the method comprising of directing a first air stream to an intake valve of the cylinder; directing a second, separate air stream to a second intake valve of the cylinder, said second air stream at a higher temperature than said first air stream; operating said first intake valve and adjusting at least one of an opening timing and a closing timing of said first intake valve to adjust engine output; and intermittently operating said second intake valve to maintain said higher temperature of said second air stream.

Abstract: To prevent inflow of condensed water to an exhaust gas recirculation (EGR) valve, an exhaust gas recirculation system includes a first gas passage, an exhaust gas recirculation valve connected to the first gas passage and selectively opening/closing the first gas passage, an exhaust gas passage disposed in the exhaust gas recirculation valve, and a second gas passage connecting the exhaust gas passage to an air-fuel mixture passage. The exhaust gas passage is tilted at a predetermined angle with respect to the second gas passage. The predetermined angle may be greater than about 10°, and in some embodiments the predetermined angle is about 15°.

Abstract: The invention relates to a method for controlling a dethrottled internal combustion engine (1) having a shared fresh gas line (10) which supplies fresh gas to a plurality of fresh gas pipes (11) which in turn supply fresh gas to each cylinder (5), having at least one intake valve (7) per cylinder (5), having a clocked valve (13) per fresh gas pipe (11) for opening and closing the respective fresh gas pipe (11) and having a fuel injector (9) for each cylinder (5) for metered addition of fuel. To improve the emission values of internal combustion engines, the chronological location of the injection time of the fuel is adjusted for the respective cylinder (5) as a function of a point in time of a change in the switch position of the respective clocked valve (13) and in addition the clocked valves (13) are controlled so that the metered addition of fresh gas is accomplished for the respective cylinder (5).

Abstract: An improved T fitting results in a more uniform flow of fumes from an engine crankcase. The T fitting combines flows from an air filter and a hose connected to the engine crankcase, into coaxial paths, and then combines the flows into a combined flow. The combined flow is drawn into an intake manifold by manifold vacuum. The combining of the flows through the coaxial paths results in a more uniform flow of fumes from the crankcase.

Abstract: Method of controlling the combustion of an internal-combustion engine, in particular a direct-injection supercharged engine, notably of gasoline type, wherein the engine comprises at least one cylinder (12) with a combustion chamber (14) within which a compression stage takes place, followed by a stage of combustion of a fuel mixture by a spark-ignition means (34), characterized in that it consists in measuring a quantity related to at least one parameter representative of the state of the fuel mixture during said stages; in determining a value that depends on the amplitude of the measured quantity; in comparing the determined value with at least one threshold value representative of the quantity related to said parameter representative of the conventional state of the fuel mixture during said stages; in detecting the start of an abnormal combustion when the determined value exceeds said threshold value and when the ignition means is not actuated; in controlling the course of the abnormal combustion detected

Abstract: Known fuel injectors have a valve-closure member, which cooperates with a sealing seat of a valve seat, and a flow exit region situated downstream from the sealing seat, the fuel spray generated by the fuel injectors having an average droplet diameter that is not small enough for future regulations governing exhaust emission. In the fuel injector according to the present invention the atomization is improved in a simple manner and the average droplet diameter is reduced without additional auxiliary power. The projections which influence the fuel flow are situated in the flow exit region.

Abstract: Ignition device for an internal combustion engine comprising an ignition coil which is feedable on its primary side by a voltage supply unit and a secondary current measuring device for measuring the course of the secondary side current and a control device for at least temporary controlling of the primary side voltage or the primary side current in dependence on the measured course of the secondary side current, wherein, subsequent to an interruption of the primary side voltage or current supply of the ignition coil during an ignition process or subsequent to the drop of the primary side voltage or the primary side current in the ignition coil below a predeterminable threshold during the ignition process, said control device energises or regulates the primary side voltage or current supply of the ignition coil above the predeterminable threshold only when the secondary side current induced thereby acts in the direction of the predetermined course of the secondary side current.

Abstract: An air-fuel ratio of each cylinder is estimated on the basis of a detection value of an air-fuel ratio sensor disposed in an exhaust confluent portion. An air-fuel ratio correction quantity is computed on the basis of the estimated air-fuel ratio of each cylinder. The air-fuel ratio of an air-fuel mixture to be supplied to each cylinder is corrected on the basis of the cylinder air-fuel ratio correction quantity to reduce a variation in the air-fuel ratio between the cylinders. When a state in which the cylinder air-fuel ratio correction quantity or its learning value of any cylinder is outside a specified range continues for a while during a period in which this cylinder air-fuel ratio control is performed, a combustion is stopped for the cylinder outside the specified range and the cylinder air-fuel ratio control is continuously performed only for other normal cylinders.

Abstract: A linear engine including a first and a second cylinder in axial alignment and a a main connecting rod passing through the first and second cylinders. A first dual sided double acting piston connected to the connecting rod in the first cylinder and a second dual sided double acting piston connected to the connecting rod in the second cylinder subdividing the two cylinders into four combustion chambers. Lubricant is supplied and returned through the connecting rod to the first and second piston.

Abstract: A toy device for use in entrapping an object including a handheld implement exhibiting at least a barrel which supports a propelling mechanism and a trigger which, further upon depressing, actuates the propelling mechanism. A projectile includes a stem and a pair of mutually hingedly supported and opposingly actuation pads, the stem being supported upon the barrel and in contact with the propelling mechanism. Upon being discharged, the pads are actuated from a first position to a second rotated position, such as through the action of a lanyard extending from the handheld implement to a release plate associated with the projectile, and in order to entrap the object such as a winged insect.

Abstract: A bow string release includes a retention portion having an interior area for containing a portion of a bow string and a barrier for selectively separating the interior area from an area external thereto. The barrier is movable from an open configuration in which the bow string may pass between the interior and external areas and a closed configuration in which the bow string may not pass between the interior and external areas. The bow string release includes an actuating portion having a trigger operatively coupled to the barrier for selectively moving the barrier between the open and closed configurations. The actuating portion includes a trigger guard for protecting the trigger from being accidentally actuated. The retention portion includes a trigger lock for selectively restricting movement of the trigger and barrier, the barrier being immovable from the closed configuration when the trigger lock is activated.

Abstract: A restraining structure for a pressure regulator of a paint ball gun includes a cylinder and a restrainer. The cylinder comprises a lower chamber. The lower chamber has an inner wall and an opening. A groove is provided at the inner wall close to the opening to receive the restrainer therein. The restrainer is to confine the movement of a regulating bolt provided in the lower chamber, preventing the regulating bolt from over adjustment to damage other parts.

Abstract: An improved solid fuel combustion apparatus intended for use in residential or light commercial settings capable of sustaining a controlled, continuous blue flame burn, resulting in high efficiency heat output with low emissions and low ash. The combustion apparatus is further capable of being thermostatically controlled, turning off combustion of the fuel when a desired temperature is reached and automatically re-igniting when more heat is called for, and also comprises improved safety features.

Abstract: An apparatus for recovering heat from exhaust air received from a restaurant kitchen. Rotating backwards inclined fan blades draw exhaust air from the kitchen along a flow path and impel it against walls of a housing, such that grease is removed from the exhaust air. A fan motor is positioned out of the flow path. The exhaust air is pushed out of the housing to a heat recovery coil directly downstream that is formed from a heat conductive material. The coil has an internal conduit through which a heat transfer fluid is supplied at a temperature below the exhaust air temperature, such that the fluid in the conduit is heated by exhaust air passing over the conductive material. After leaving the conduit, heat energy is transferred from the fluid to makeup air for return to, or to water for use in, the restaurant.

Abstract: An additional bottom adapted to be fixed to an outer surface of a bottom of a vessel, provided with holes which are designed to be filled by a material of the vessel during a coining step which fixes the bottom to the vessel, further comprising protrusions which protrude from an outer surface of the bottom of the vessel.

Abstract: A frame system suitable for mounting a solar module on a roof, the frame system comprising at least one frame comprising an upper frame member, a lower frame member a right-side frame member, a left-side frame member, at least one projecting member that is attached to or is an integral part of at least one of the side frame members, and projecting in a direction toward or substantially toward the fewer frame member; and a batten comprising a recess for engaging the projecting member of the frame. The frame optionally comprises a means for affixing the frame to another frame.

Abstract: A comprehensive aerosol therapy for administration to a patient in need of treatment is provided. More particularly, the aerosol therapy kit provides a seamless conduit for a patient to receive in-office or hospital inhalation treatments and access to drugs and equipment for continuing home use.

Abstract: A spacer device for the oral administration of a volatile medium containing a medicament comprises a chamber (110) having an inlet (102) to admit a measured dose of medicament and an outlet (104) to be received in the mouth, wherein the spacer comprises a butterfly valve (106). Preferably, the chamber comprises two frustoconical members assembled together coaxially at their divergent ends, said inlet and outlet being respectively at the opposed convergent ends.

Abstract: In one embodiment, a human-powered dry powder inhaler comprises a human-powered compressible component operable to discharge an air pulse at an outlet at a pressure of about 1-40 psi; an inflatable reservoir operable to receive an air pulse discharged from the human-powered compressible component to provide an aerosol of a dry powder pharmaceutical formulation in the reservoir, the reservoir including an outlet valve; and a receiving mask in communication with the outlet valve and operable to receive an aerosol of dry powder from the reservoir and to deliver the aerosol to at least a mouth or nose of a patient. In another embodiment, the inhaler comprises a human-powered compressible component operable to discharge an air pulse at an outlet of a polymeric pressure release valve at a pressure of about 1-40 psi; and a receiving mask in communication with the outlet of the compressible component and operable to deliver an aerosol of dry powder to at least a mouth or nose of a patient.

Abstract: Inhaler counter (20) comprising a counter housing (390), a rocker arm (200) with a pawl (210), the rocker arm being pivotally supported by the housing and arranged to perform a rocker movement in response to a linear actuation motion, a return spring (220) for resetting the rocker arm, a ratchet wheel (230) engagable with the pawl to convert the movement of the rocker arm into an incremental rotational motion of an axle arrangement (240) advancing a display means (60), the axle arrangement further comprising a back rotation prevention means (280) in the form of a spring loaded friction brake and a worm gear, the display means comprising rotatable indicator means (120) with teeth that engage the worm-gear and a stationary scale.

Abstract: A breathing apparatus designed to display at least one condition associated with the breathing apparatus to the user of the breathing apparatus. The breathing apparatus includes a breathing mask, a display assembly and a sensor assembly. The display assembly includes at least one display designed to display at least one condition of the display assembly and/or the sensor assembly. The breathing apparatus design can be designed to enable a third party to view at least one condition of the display assembly and/or the sensor assembly while a user is wearing the breathing mask. The breathing apparatus can include a sealing arrangement for forming a seal between a circuit board and/or other electronic components and a housing of the display assembly and/or the sensor assembly.

Abstract: Methods, systems, and computer products for filling lungs. Exemplary embodiments include a method for filling lungs, the method including identifying an ailment for active lung filling treatment, determining a preset volume to fill into the lungs, determining an inhalation period and determining an exhalation period.

Abstract: A method and corresponding system for providing breathing cues includes monitoring respiration of a user and determining a user breathing frequency including an inspiration portion and an expiration portion of the breathing, supplying a high positive air pressure to the user during the inspiration portion and a low positive air pressure during the expiration portion in substantial synchronicity with the user's respiration, comparing the user breathing frequency with a target breathing frequency, and when the user breathing frequency is greater than the target breathing frequency, increasing, in a predetermined manner, a time over which the high positive air pressure is supplied to the user, and adjusting a time over which the low positive pressure air pressure is supplied to the user.

Abstract: Isolation devices and methods of controlling a partition are disclosed. Devices according to the invention have a housing disposed about a movable partition. The housing has respirator and patient sides on respective first and second sides of the partition. The housing also has: (a) a respirator orifice on the respirator side, adaptable to be in pneumatic communication with a respirator; (b) a patient inspiration orifice on the patient side, adaptable to be in pneumatic communication with a patient; (c) a bias inflow orifice on the patient side, adaptable to be in pneumatic communication with a source of inspiratory gas; and, (d) an expiration return orifice on the patient side. The devices may further include a partition position sensor, a CO2 scrubber, and a controller operable to regulate gas flow to the bias inflow orifice based on partition position.

Abstract: An exhalation valve assembly for a respirator, said assembly comprising an upstream one-way flap valve and a downstream one-way flap valve, both mounted within a housing. The valves are 5 spaced apart to define therebetween a volume which acts as a ‘dead space’ in which a portion of the just-exhaled air will rest so that, should the upstream valve leak for any reason, any leakage air drawn back into the respirator will be taken from this just-exhaled air, and will thus not be contaminated by the ambient air.

Abstract: A cockpit oxygen mask comprises a mask body, an oxygen inhalation valve, a mixed air inhalation valve, an exhalation valve as well as with a control device. At least the oxygen inhalation valve is signal-connected to the control device. The oxygen inhalation valve is designed as an electromagnetically actuatable valve, and comprises at least one throughflow path which may be closed by a magnetically movable valve body, wherein the throughflow path is limited by a magnetizable wall, and wherein the wall comprises at least one discontinuous location which deforms a magnetic field produced in the wall.

Abstract: An air filter that a user places in his mouth when necessary. The filter is in the shape of a plug and has inlet air ports defined therein with the air passing through filter media before passing out of outlet ports which are located inside the user's mouth when the filter is in use. The filter can be worn around a user's neck to be readily available when needed.

Abstract: A patient interface device including a cushion assembly having a cushion-in-a-cushion arrangement and a system for supplying a flow of gas to a patient using such an interface device. The patient interface includes a mask shell having a patient side and an outer side opposite the patient side adapted for receiving a supply of gas. A seal cushion contacts a first area of a patient's face to form a seal therewith. A support cushion encircles the seal cushion and includes a first end portion that contacts a second area of a patient's face.

Abstract: The invention is to provide a facemask roll made of elastic nonwoven fabric for the merits of collecting the masks continuously during the manufacturing process and the convenience of dispensing the facemasks to users. The method of manufacturing comprises feeding one or multiple pieces of elastic nonwoven fabric, layering and folding, welding and sealing, die-cutting, punching, winding on a core, and finishing with determined quantity to make a roll.

Abstract: This document discusses, among other things, systems, devices, and methods for using surface energy to assist in fluid transport or separation. One example includes removing mucus from a subject's lungs during mechanical ventilation of the subject using a tracheal tube. At least one wicking fluid pickup port is located more distal than a sealing device between the tracheal tube and the trachea. Surface energy assists in introducing mucus into the port. Ventilation of the subject is not impaired by the mucus removal. Safety venting reduces or avoids damage to tissue occluding the port. Other structures may assist in directing the mucus toward the port. Various illustrative examples include single lumen tracheal tubes, double lumen tracheal tubes, two-piece tracheal tubes (having outer and inner cannulas) and bronchial blockers.

Abstract: The present invention relates to formulations of nucleotide reverse transcriptase inhibitors (N(t)RTIs), preferably [2-(6-Amino-purin-9-yl)-1-methyl-ethoxymethyl]-phosphonic acid (tenofovir, PMPA), or a physiologically functional derivative thereof, suitable for topical application and their use in the prevention of HIV infections.

Abstract: One aspect relates to reducing a pressure differential across one or more supporting surfaces of a body surface of an individual at least partially by displacing at least one displaceable contouring unit to at least partially conform to one or more contours of the body surface of the individual. Certain aspects can relate to stabilizing at least the one or more supporting surfaces of the body surface of the individual at least partially with at least one of the at least one displaceable contouring unit Other aspects can relate to relatively displacing at least one displaceable contouring unit with respect to a medical device portion based at least in part on a contour of an individual to support at least a portion of the individual while limiting pressure applied to the individual.

Abstract: An orthotic device (100) for retaining a patient's mandible in an advanced or protrusive position comprises an intraoral anterior mandibular abutment surface (125) for resisting mandibular retraction by abutting the gingiva covering the mandible and an extramaxillary anterior maxillary abutment surface (115) against which the intraoral anterior mandibular abutment surface (125) is braced. In order to resist rotation of the dental orthotic produced by the interaction of the intraoral anterior mandibular abutment surface and the extramaxillary anterior maxillary abutment surface, the orthotic device is provided with an intraoral posterior maxillary abutment surface (140). The relative positions of the maxillary and/or mandibular abutment surfaces may be adjusted to suit the requirements of the user.