Abstract: A piston for an internal combustion engine with a separate head and skirt which are joined by a piston pin. The ring belt extends downward from the head and terminates above the pin. The space between the lower edge of the ring belt and a section of the head defines a cooling oil ring space. A depression is formed in the head and is partly defined by the section. The section has a thickness of between four percent and seven percent of the piston diameter, corresponding to an angle of zero to sixty degrees of the section with respect to a vertical longitudinally extending line. The thickness of the head above the space is six percent to twelve percent of the piston diameter. The top of the space is below the top ring groove. Above the second ring groove, the ring belt has a thickness of greater than two and one-half percent of the piston diameter.

Abstract: A piston structure includes protection of the peripheral edge portion of a lubricant injection nozzle receptacle cut-out. The piston structure employs mechanisms for reinforcing the peripheral edge portion of the cut-out to an extent that can avoid concentration of the stress and thus can avoid the formation of cracks.

Abstract: Present day diesel engines having aluminum piston assemblies are limited to combustion chamber pressures of approximately 12,410 kPa (1,800 psi) whereas the desire is to increase such pressures up to the 15,170 kPa (2,200 psi) range. To reach such levels the instant piston assembly includes a steel piston member having an upper cylindrical portion of a diameter "D" and a compression height "CH". The ratio of the compression height "CH" to the diameter "D" being within the range of from 60% to 45%. The piston member is preferably forged and subsequently machined to precisely controllable dimensions. Moreover, the piston assembly is preferably of the articulated type and includes a forged aluminum piston skirt connected to the piston member through a common wrist pin. Engine manufacturers are also demanding a smaller engine package size while retaining power output, improve fuel consumption and decreased emissions.

Abstract: A working cylinder is described which features a cylinder of compact construction. The openings provided for the tension member can be very well sealed by simple means. The tension element features a cross-section having a continuous circumferential line. The size of the cylinder is also reduced through the use of a generally elliptical piston. The tension element is preferably comprised of several plastic tension strands encased in a jacket of plastic material which also has a generally elliptical cross-sectional shape.

Abstract: A rotary actuator comprising a housing which defines an arcuate chamber, the housing including a first monolithic portion in which the arcuate chamber is completely contained, a piston disposed in the housing for reciprocable movement in the arcuate chamber, a shaft journaled in the housing and connected to the piston and being rotated in response to movement of the piston, a floating seal assembly carried by one of the piston or the housing for effecting sealing between the piston and the housing, a fluid pressure port to introduce fluid into the housing to effect movement of the piston in the first direction and a means such as fluid pressure or a spring return to effect movement of the piston in an opposite second direction, the actuator in one preferred embodiment employing a spring return which provides a substantially constant torque acting upon the shaft as the spring moves from a compressed first position to an uncompressed second position such that the torque acting upon the shaft in both rotational

Abstract: A fluid operated actuator includes a housing having a longitudinally extending aperture with open ends. First and second end caps are attached to opposite ends of the housing forming a chamber within the housing. A longitudinally reciprocal piston and attached rod are disposed within the chamber with the rod extending externally of the chamber through one of the end caps. The piston is adapted for reciprocal movement from one end limit of travel adjacent the first end cap to a second end limit of travel adjacent the second end cap. At least one of the first and second end caps includes a longitudinal aperture in communication with the chamber and a transverse aperture communicating between the longitudinal aperture and an exterior of the end cap. A sleeve is connected to the rod adjacent the piston and is engageable within the longitudinal aperture of the end cap when the piston is in the end limit of travel.

Abstract: A jack comprising a casing consisting of two flanges connected by a tubular element in which is sliding a piston connected to a rod itself slidably mounted to extend through one flange, the ends of the tubular element which is oval in cross-section as well as the piston being fast with the flanges, respectively, through a double crimping, namely a crimping of the ends of the tubular elements onto the flanges and a crimping of the flanges onto these ends.

Abstract: A piston ring whose contour deviates from the circular shape, and in particular an elliptical or oval piston ring, which, when seen in the circumferential direction, has regions that, in the installed state as well as in the operating mode, exert less radial contact pressure than the remaining surface regions in order to reduce wear of and leakage by the ring.

Abstract: Engines having cylinders of noncircular cross section wherein the cylindrical curve is generated at a preselected constant outwardly normal distance from a closed curve. The closed curve is defined as including two spaced points on a major axis of symmetry of the cylinder with two continuously curved portions extending between these points and curved outwardly from the major axis. The closed curve about which the cylinder curve is generated is preferred such that there is a continuous change of curvature without discontinuity in that curvature in the cylindrical curve. The avoidance of discontinuity in the generating curve aids in mass production considerations and cutter life. A plurality of intake and exhaust port arrangements are disclosed illustrating four intake ports and four exhaust ports on opposite sides of the major axis of symmetry of the defined cylinder. In one embodiment, the outermost of the ports are smaller and are positioned closer to the major axis of symmetry.

Abstract: It is a question of a piston and cylinder unit comprising a cylinder barrel defining a piston space, a piston able to run axially in said barrel with a support action due to a peripheral bearing surface of the barrel. The piston includes at least one annular running belt which is coaxially arranged thereon along part of the length of the piston. The belt has a surface facing radially outwards which makes contact with the inner bearing surface of the barrel with sliding fit to support the piston, while an inwardly directed surface of the belt bears on an outer peripheral surface of the piston, which is spaced from the bearing surface of the barrel. The belt further has an inwardly directed retainer spur fitting into a groove-like peripheral recess in the piston. The belt is made of a material with resiliently elastic properties and is interrupted at one position on its periphery so that in the fitted condition of the belt there is a closed interruption able to be opened out for fitting purposes.

Abstract: A piston-cylinder assembly wherein in the cylinder housing there is provided a cylinder chamber extending in axial direction, in which cylinder chamber a piston is movably guided in axial direction. Both the piston and also the cylinder chamber have a cross section which is different from a circular shape. A permanent-magnet piece is arranged fixedly in the area of the outer circumference of the piston. A switch arranged in the area of the linear path of movement of the permanent-magnet piece is provided on the outside on the cylinder housing, which switch can be operated without contact by the magnetic field of the permanent-magnet piece.

Abstract: A vacuum-type brake booster device for automotive use having a shape such that the mounting of the booster device and surrounding components inside the engine compartment of the vehicle is markedly eased. The shell of the booster device, and hence the diaphragm contained therein, has the shape in the plane of the diaphragm of a circle having a peripheral segment thereof removed. This causes the effective center of the diaphragm to be shifted from the center of the circle. The input and output shafts and the master cylinder are mounted on the shell aligned with the offset effective center of the diaphragm.

Abstract: A tread-brake unit copmrises, as a unitary structure, a brake shoe (300) for engaging a vehicle wheel tread, a brake actuator (100) having an output member (19) via which the brake shoe (300) can, firstly, be moved into engagement with the wheel tread and, thereafter, a braking force generated by the actuator (100) can be transmitted to the brake shoe (300), and a slack adjuster (200) by which clearance between the brake shoe (300) and the wheel tread, in the "released" condition of the unit, can be maintained substantially constant. The slack adjuster (200) has a pair of fast-threaded units (20,21), each nut being threadedly engaged with and rotatable on the output member (19) of the actuator (100).

Abstract: In a two-cycle internal combustion engine (10), the piston (20) has an outer peripheral oval shape (58) with a minor axis (62) offset from the centerline (54) of the wrist pin (26) towards a line (56) through the intake and exhaust ports (16 and 18). The outer peripheral shape of the piston also has increasing ovality, from at least the wrist pin (26) upwardly to at least the piston rings (22, 24).

Abstract: A power conversion device which can efficiently convert between fluid pressure and rotary motion. The device includes a piston plate, which is surrounded by an array of pressure chambers and engageable with a shaft and its accompanying gear assembly. Manifold networks act as valves to control the sequential pressurization and depressurization of the pressure chambers so as to produce orbital movement of the piston plate about the shaft, as though it were floating on a cushion of air.

Abstract: A piston, particularly for internal combustion engines, of which the bearing surfaces with which the piston comes into contact with the engine cylinder bore lie on a generated surface which runs asymmetrically to the axis of an engine cylinder accommodating the piston without clearance in the longitudinal direction of the piston and/or in the circumferential direction.

Abstract: Structure and method are disclosed for providing timed valving in which a nutating plate having an opening defined therethrough moves relative to at least one other nominally static plate having a complementary opening defined therethrough, the nutating plate at one portion of the nutating travel bringing the opening defined therethrough in alignment with the complementary static opening and in another portion of the nutating movement positioning such opening therethrough in a spaced, sealing relationship relative to the complementary static opening. Either the nutating or nominally static plate may be utilized in pairs such that a sandwiched relationship between one type of plate and the other exists.

Abstract: A two-cycle internal combustion engine having an oblong cylinder and an oblong piston therein. The engine includes two sets of scavenging ports at either end of the oblong cylinder having at least three ports each. Scavenging passages extending to the scavenging ports may be directed at sequentially increasing angles of inclination to the local normal with the cylinder away from the exhaust porting. In this way, flow may be directed across the piston head away from the exhaust porting and then upwardly to return toward the exhaust porting. A domed piston is also disclosed having discrete guide surfaces on the domed surface of the piston to specifically direct incoming air/fuel mixture upwardly from each of the scavenging ports. An element of the cylinder midway in the long dimension of the cylinder extends in the direction of piston movement without porting so as to provide a smooth wall surface.

Abstract: Engines having cylinders of noncircular cross section wherein the cylindrical curve is generated at a preselected constant outwardly normal distance from a closed curve. The closed curve is defined as including two spaced points on a major axis of symmetry of the cylinder with two continuously curved portions extending between these points and curved outwardly from the major axis. The closed curve about which the cylinder curve is generated is preferred such that there is a continuous change of curvature without discontinuity in that curvature in the cylindrical curve. The avoidance of discontinuity in the generating curve aids in mass production consideration and cutter life. A plurality of intake and exhaust port arrangements are disclosed illustrating four intake ports and four exhaust ports on opposite sides of the major axis of symmetry of the defined cylinder. In one embodiment, the outermost of the ports are smaller and are positioned closer to the major axis of symmetry.

Abstract: A piston-cylinder arrangement, particularly useful for the press shoe of an extended nip press. The cylinder is a fluid pressure cylinder with a piston, which is fluid pressure reciprocated, disposed in the cylinder chamber. The cylinder and piston are polygonal around their peripheries. A circumferential groove in the cylinder wall carries a plurality of sealing pieces which are urged outwardly of the groove and against the periphery of the piston. The sealing pieces comprise corner pieces disposed at the corners of the polygonal cylinder and second sealing pieces joining the corner pieces. Where the corner and second sealing pieces meet around the periphery of the cylinder, they have overlying, overlapping surfaces that are oriented perpendicular to the reciprocation of the piston. A spring in the groove may urge some of the pieces outwardly toward the piston.

Abstract: In a light alloy piston having a convex and oval external shape, the piston skirt has in the cold state a larger running clearance at its top end than at its bottom end. In order to reduce the friction loss of such piston, the piston skirt has a larger ovalness adjacent to the horizontal plane extending through the pin axis than in the remaining regions of the piston skirt.

Abstract: The machine is an engine or pump with a box shaped piston positioned between two stationary sidewalls. Opposite inward ends and inwardly facing moving sidewalls of the piston act with the two stationary case sidewalls and a block-shaped central head to define a pair of working chambers. The piston moves as restrained by a crankshaft to extract or add energy to the working chambers. Force is transferred between the piston and the crankshaft by means of a slide block on the crankshaft and the inner surface of a pair of parallel walls connected to the box shaped piston. Through the use of suitable cams and valves, four-cycle, two-cylinder equivalent engines and two-cycle, one-cylinder equivalent engines can be produced per piston. The planar walls of the machine maximize displacement while reducing mechanical stress and allowing use of heat resistant coating material, such as ceramics for thermal protection so that radiantly cooling rather than separate fluid or gaseous cooling systems can be used.

Abstract: An anvil for our ultrasonic textile slitting apparatus comprises an elongated, flat, substantially rectangular, housing in which two pistons are disposed for motion relative to one another along the longitudinal axis of the housing. A first piston, responsive to fluid pressure, is urged against the force exerted by springs into motion toward the second piston for causing the second piston, which is provided with a slitting implement, to be urged toward contact with the output surface of an ultrasonic horn. Further, springs are interposed between the first and the second piston for urging the pistons apart, but becoming compressed responsive to such fluid pressure. The combination of fluid pressure and springs causes the slitting implement to be kept in continuous contact with the horn despite the very high acceleration forces manifest at the horn output surface. In addition, the springs provide vibratory isolation from the vibratory energy of the horn.

Abstract: A gas refrigerant compressor comprises a shaft having a first portion and an offset portion. A body supports the first portion of the shaft for rotating movement around an axis of rotation and defines a compression chamber. A compression member is adapted for reciprocating movement within the compression chamber. The compression member is connected to the offset portion of the shaft such that rotating the shaft draws gas refrigerant into the compression chamber upon movement of the compression member toward the axis of rotation and exhausts compressed gas refrigerant out of the compression chamber upon movement of the compression member away from the axis of rotation.

Abstract: A sealing apparatus is disclosed for a device having variable volume chambers formed by the walls of a case and a piston. The device includes a piston assembly having an outer piston structure with an inner piston structure therein. The inner piston structure is mounted on an eccentric on a crank shaft, the rotation of which causes nutating movement of the inner piston structure and a reciprocal linear movement of the outer piston structure. First sealing elements are mounted on the outer piston structure to provide sealing for the chambers having the outer piston structure forming part of the chambers, and second sealing elements are mounted on the ported faces of the inner piston structure to provide sealing for the chambers having the inner piston structure forming part of the chambers. Each sealing element includes one portion received in grooves in the piston structures and another portion with a plurality of spaced raised sections which engage the case walls.

Abstract: In a reciprocating piston internal combustion engine, an upwardly arcuately shaped combustion space is formed in the cylinder head, which contains suspended valves arranged V-shaped. The valves are moved as close as possible to the combustion space boundary and form narrow spaces with respect thereto. The radii of the transitional arcs from the valve-end faces to the combustion space boundary increase continuously from the narrow spaces in both circumferential directions of the combustion space boundary and reach their maximum values in the center plane between the valves. The combustion space curvature is matched to the predetermined angles of inclination of the valves.

Abstract: Structure and method for providing timed valving in which a nutating plate having an opening defined therethrough moves relative to at least one other nominally static plate having a complementary opening defined therethrough, the nutating plate at one portion of the nutating travel bringing the opening defined thereto in alignment with the complementary static opening and in another portion of the nutating movement positioning such opening therethrough in a spaced, sealing relationship relative to the complementary static opening. Either the nutating or nominally static plate may be utilized in pairs such that a sandwiched relationship between one type of plate and the other exists. The static and nutating plates may advantageously be biased together. Timing of the opening and closing of the valving structure may be adjusted relative to a nominal rotating shaft such as to provide opening and closing cycles of selected portions of an entire rotation.

Abstract: A compact lightweight engine or pump is constructed having a H-shaped piston, usually double acting. Each end of the piston has extending surfaces which form two moving sidewalls which act with two case sidewalls and a block-shaped head protrusion to define a working chamber with the appropriate top surface of the piston which moves to extract or add energy to the working chamber. Energy is transferred between the piston and a crankshaft by means of a slide block on the crankshaft and the inner surfaces of a pair of parallel walls forming the center of the "H" of the piston, whose opposite surfaces form the piston top surfaces. Through the use of suitable cams and valves, 4-cycle, 2-cylinder equivalent engines can be produced. With suitable porting, baffles, and/or auxillary compression means, 2-cycle engines can also be produced as well as air pumps.

Abstract: The invention relates to a hydraulic rim brake for bicycles with a triggering mechanism which is attached to the handlebar of the bicycle and is actuated by a hand lever, with two brake cylinder housings which are attached to the frame of the bicycle in oppositely located relationship to each other and enclose between them a wheel rim, the brake cylinder housings being connected by pressure lines to the triggering mechanism, with pistons displaceable in the brake cylinder housings, and with brake shoe supports arranged on these pistons for supporting brake shoes engaging the rim. In order to protect the piston from the effect of harmful bending moments, provision is made for the brake shoe supports to be in the form of flanges which are connected to the piston and are each displaceable parallel to the motion of the brake piston in a slide guide provided on the brake cylinder housing, and for the slide guide to simultaneously constitute abutments for absorption of the braking forces.

Abstract: A piston ring for an internal combustion engine having a piston and a cylinder of an elliptical or oblong circular cross-sectional shape is divided into two or more segments which are connected end to end in a ring. Each of the end-to-end joints between the neighboring segments is so designed as to provide an adequate surface pressure of the piston ring against the cylinder wall when installed in a cylinder. In one embodiment, the piston ring comprises two arc segments each of which has two inward projections projecting from both ends of the segment, respectively. In the installed state, the two inward projections of one arc segment abut against the inward projections of the other segment, respectively, in such a manner that an abutting pair of the inward projections at each joint produce a force which tends to increase a gap clearance between the ends of the segments.

Abstract: A disc brake includes a rotor, an opposed pair of friction pads each arranged on an opposite side of the rotor, and a caliper which straddles the circumferential periphery of the rotor. The caliper has a pair of leg portions each arranged on an opposite side of the rotor. The caliper is arranged to push one of the friction pads against the rotor by a piston disposed within a cylinder formed in one leg portion and to push the other friction pad against the rotor on the other side with the other leg portion which is arranged to be slidable by a force of reaction to the thrusting action of the piston. A load distribution plate part is formed at the end of the piston which engages the back of the friction pad. This plate part on the piston is arranged to restrict rolling or turning of the piston around its axis by engaging the inner surface of a saddle portion of the caliper straddling the rotor.

Abstract: An unsymmetrical cylinder-piston of a rotary compressor having a body with a bearing for receipt of a rotatable cylinder-piston shaft therein; two spaced walls extending from the body and having opposing parallel surfaces; a wall interconnecting the two spaced walls at their end remote from the body to form an opening in the cylinder-piston for receipt of a rectangular piston in slidable relation therein, the spaced walls being bolted to the body and connecting wall and the body being balanced making the center of gravity of the unsymmetrical cylinder piston on or close to the axis of the bearing located therein.

Abstract: Caliper brake apparatus has a caliper housing, an actuator including a plunger movable axially longitudinally to urge a lining against a rotating disc, and the lining having the form of a plate which is laterally elongated and defines a plane generally perpendicular to said axis. The apparatus is improved by:(a) the plunger having cross sections in planes normal to said axis and characterized as laterally elongated and as having lateral length dimensions which are substantially greater than the plunger transverse width dimension, the width dimension being generally normal to said axis and to said lateral length dimension, and(b) the actuator having a recess receiving the plunger, the recess having cross sections in planes normal to said longitudinal axis characterized as conforming in shape to said plunger cross sections.In addition, one or more removable end plates may be employed to removably retain the lining in position.

Abstract: A reduced impact piston assembly including a cylindrical body with a cavity formed therein and having a cross-bore formed therethrough which intersects the cavity. The cross-bore receives a piston pin which has an exposed intermediate portion aligned with the cavity for attachment of a connecting rod thereto. A wide groove is formed about the outer circumference of the cylindrical body which has its center aligned with the center of the cross-bore. Positioned within this groove are a pair of C-shaped inserts, the legs of which abut the ends of the piston pin to prevent axial movement of the pin within the cylindrical body. The C-shaped inserts cooperate with the pin to form a closed loop having a circumferential length which is larger than the circumferential length of the cylinder body. In addition, a portion of each of the C-shaped inserts is in constant contact with a cylinder wall.

Abstract: An engine employing oval pistons and cylinders with dual connecting rods for each piston. The connecting rods are connected to each piston by a common wrist pin and to a composite crankshaft. The crankshaft includes a main bearing between the connecting rods of each of the pistons. It also includes a middle portion associated with each piston including two crank pins and the shaft therebetween for receipt of the centrally located main bearing.

Abstract: A four-cycle internal combustion engine comprising a cylinder bore formed in a cylinder block, a piston slidably fitted in the cylinder bore, and a combustion chamber formed in a cylinder head above the piston. The bore, piston and combustion chamber have an elongated non-circular cross-section which, for example, can be of elongated circular or elliptical shape. An intake system for fuel mixture is connected to the combustion chamber to supply fuel mixture to a central region of the combustion chamber and an exhaust system is connected to each end of the combustion chamber in an outer region for discharge of exhaust gases.

Abstract: A piston and cylinder are oblong in cross section with the major dimension at right angles to the crankshaft axis. An inlet valve and an exhaust valve are mounted near opposed end portions of the oblong cylinder with a spark plug arranged along the minor centerline, either between the valve or displaced laterally from the major centerline of the cylinder. The valves are symmetrically inclined with respect to the central axis of the oblong cylinder, and are operated from separate camshafts. The combustion chamber roof is a concave surface having both major and minor centerline surface elements which employ radii of curvature greater than the radius of curvature of the cross-sectional ends of the oblong cylinder.

Abstract: A pneumatic drive has at least one working cylinder composed of a pair of parallel stationary walls and a pair of walls which extend at right angles to the first pair and are movable relative thereto, towards and away from each other. This varies the volumetric content of the cylinder and changes one transverse dimension thereof. A piston is reciprocable in the cylinder and constructed of a plurality of sections which together define the piston surface that is exposed to the pressurized working medium of the drive. During the working stroke these sections move apart from one another so as to together define a piston surface of maximum area; during the idle (return) stroke the sections are moved together by an arrangement provided for this purpose, so that some of them are concealed behind or within others, thus reducing the piston surface to an area which may only amount to about 20% of the former area.

Abstract: Disclosed is a pressure cylinder apparatus having a cylinder and a slidable member such as a ram or piston which is slidable back and forth in response to charging and discharging of fluid into and out of the cylinder, wherein that the said slidable member has a polygonal cross-sectional shape and that the said stopper assembly having an aperture of a polygonal shape corresponding to the polygonal cross-section of the slidable member is provided in the plane perpendicular to the direction of movement of the slidable member so that the stopper assembly prevents or limits the undesirable rotation of the slidable member during outward movement of the slidable member, and disclosed also is a hydraulic press incorporating the pressure cylinder apparatus stated above, and the end surface of the said slidable member is shaped and sized to conform with the press mold part to which the end surface portion is connected.

Abstract: A piston machine, e.g. an internal-combustion engine, compressor or pump, in which a piston is reciprocatable in a cylinder and crankshaft is provided with an eccentric pin received in a transverse slot of the piston and preferably in a massive portion of the body thereof, so that piston rods and the like are avoided.

Abstract: A holder for a roller slitting knife is provided comprising a first selectively-operable piston assembly including a first piston and a first piston cylinder housing. The first piston has a non-circular, cross-sectional portion preferably configured as a curved triangle of constant diameter received in the mating bore of the housing. A second selectively-operable piston assembly including a second piston and a second piston housing is mounted to the first assembly and disposed for operation in a direction transverse to operation of the first piston assembly. A roller slitting knife is mounted to the second piston assembly whereby the knife is selectively positioned for operation upon selective operation of the first and second piston assemblies.

Abstract: An internal combustion engine has an oblong piston sliding in an oblong cylinder bore and cooperating with a cylinder head to form an oblong combustion chamber. Intake and exhaust valves communicating with the combustion chamber are positioned in series in the direction of the length of the combustion chamber, each valve having a large head extending for substantially the whole width of the combustion chamber. Intake and exhaust passages communicating with the combustion chamber through the intake and exhaust valves extend away from the combustion chamber at right angles of the length thereof to minimize blow-by from the intake valve to the exhaust valve.

Abstract: A piston ring for use with an oblong piston and cylinder has a gap at one end. A resilient corrugated expander is positioned behind the piston ring and within the piston ring groove in the piston. The expander also has a gap and the two gaps are adjacent each other and in close alignment.

Abstract: An engine employing oval pistons and cylinders with dual connecting rods for each piston. The connecting rods are connected to each piston by a common wrist pin and to a composite crankshaft. The crankshaft includes a main bearing between the connecting rods of each of the pistons. It also includes a middle portion associated with each piston including two crank pins and the shaft therebetween for receipt of the centrally located main bearing.

Abstract: A four-cycle internal combustion engine comprising a cylinder bore formed in a cylinder block, a piston slidably fitted in the cylinder bore, and a combustion chamber formed in a cylinder head above the piston. The bore, piston and combustion chamber have an elongated non-circular cross-section which, for example, can be of elongated circular or elliptical shape. An intake system for fuel mixture is connected to the combustion chamber to supply fuel mixture to a central region of the combustion chamber and an exhaust system is connected to each end of the combustion chamber in an outer region for discharge of exhaust gases.

Abstract: An internal combustion engine is provided with at least one oblong cylinder and an oblong piston mounted to reciprocate therein. A piston ring is positioned within an annular piston ring groove formed in the piston, the piston ring including an outer ring in contact with the cylinder, an inner ring and a biasing means such as a corrugated plate spring positioned between the inner ring and the outer ring. The inner ring is normally slightly spaced apart from the inner periphery of the piston ring groove so that the piston ring is allowed to be laterally displaced the amount of such spacing during piston oscillation, thereby providing improved sealing between the piston and cylinder.

Abstract: An internal combustion engine has an oblong piston sliding in an oblong cylinder bore, with the major dimension at right angles to the crank shaft axis. A set of intake valves communicates with the oblong combustion chamber near one end thereof, and a set of exhaust valves communicates with the combustion chamber near the other end thereof. Each of the intake and exhaust valves are of the poppet type and each has a longitudinal axis inclined with respect to the cylinder bore axis, the axes of two intake valves and two exhaust valves lying in the same plane and intersecting at a common point. The angular spacing between said two intake valves and said two exhaust valves are substantially the same.

Abstract: A powder-actuated tool is provided with a barrel assembly having two parallel, communicating bores and a piston comprised of joined, offset portions, with one of said portions being adapted to slide in one bore while another portion is sliding in the other bore, whereby it is possible to provide a relatively short tool, capable of setting long fasteners, with continuous centering, of the fasteners, during their displacement.

Abstract: A piston ring for an oblong piston reciprocating in an oblong cylinder has side portions which merge at one end with a relatively long convex portion. Each side portion also merges with a relatively short convex end portion, respectively. The short convex end portions define a gap between them. Upon installation of the piston ring into a groove on the piston and within the wall of the oblong cylinder, the width of the gap is substantially reduced, thereby to stress the side portions and cause them to reduce pressure variations between the piston ring and the cylinder wall around the periphery of the piston ring. The oblong piston and cylinder may have straight side walls merging with arcuate end walls, or may be substantially elliptical in cross section.

Abstract: A four cylinder four cycle spark ignition engine has oblong pistons each mounted to reciprocate in sliding contact with an oblong cylinder. Intake valves in a series are positioned in a straight line on one side of and parallel to a central plane extending through the longest dimension of each oblong cylinder. Exhaust valves in a series are positioned in a straight line on the other side of and parallel to that central plane. A cam shaft operates all of the intake valves and another cam shaft operates all of the exhaust valves.