Abstract: A yoke bushing that reduces the cyclic movement between the main shaft of a ball-and-race type coal pulverizer, thereby resulting in longer shaft life and reduced incidences of shaft failure. The yoke bushing is comprised of a flexible structure that provides individual contact areas which will have, at the same locations, equal stress fields between the main shaft and the yoke bushing.

Abstract: A tolerance ring (10) for providing an interference fit between inner and outer components (36, 50) is disclosed. The tolerance ring (10) comprises a deformable band wound to form a first layer (111) having a plurality of radially extending projections (12, 13, 15) around its circumference and an unformed second layer (110) which overlaps with the first layer. The second layer acts as a force diffuser to spread the forces transferred through the projections on to the inner or outer component.

Abstract: The invention relates to a fastening element (1), in particular for connecting two parts (2, 3) in a chassis, which fastening element has a central axle (4) on which at least two support elements (5, 6, 7, 8) of damping material are arranged at an axial distance from one another. In order to achieve an improved performance of the vehicle which has the chassis, the invention provides that at least one of the support elements (5, 6, 7, 8) is composed of at least two different components (9, 10) and/or of different materials.

Abstract: A valve retainer is provided for securably retaining a discharge valve assembly within a recess formed in a scroll. The valve retainer can be installed between the recess of the non-orbital scroll and the discharge valve assembly to retain the discharge valve assembly at the recess. The valve retainer can include a ring-like body having inwardly and/or outwardly extending tangs for cooperating with structure formed on the respective valve and the recess of the non-orbital scroll.

Abstract: A disc brake having an anchor bracket fixed to a vehicle, a rotor fixed to and rotatable with a wheel and a caliper that spans the disc and supports a pair of opposed braking pads with respect to the rotor. Parallel alignment members fixed to the caliper and having a corresponding set of generally parallel bores for receiving the alignment members in the anchor bracket to allow limited relative movement and caliper translation during a brake application and subsequent release. Plastic inserts disposed intermediate an alignment member and a corresponding bore to provide a desired minimum running clearance there between. The plastic inserts being formed and remaining in situ within the respective bores through a sprues or gate that extend from and are generally transversely to a bore to align the alignment members with the bores and corresponding the braking pads with the rotor.

Abstract: A link for connecting a pair of spaced members having a set of aligned holes, together, generally including a bolt having threaded end portions and a pair of upset portions based inwardly relative to the threaded end portions thereof, a pair of inner grommets each formed of a resilient material, mountable on the bolt and having a portion functional to snap-fit on one of the upset portions of the bolt when such grommet is mounted on the bolt, a pair of outer grommets each formed of a resilient material, mountable on the bolt and cooperable with one of the inner grommets to engage one of the members therebetween and a pair of nuts threadable on the threaded portions of the bolt, engageable with an exterior grommet mounted on the bolt.

Abstract: A pivot assembly is provided for attaching a closing wheel frame to a planter. The closing wheel frame has a pair of closing wheels attached at a rear end and a pair of mounting openings formed at a front end. The pivot assembly includes ball bearings having outer races fit loosely within each of the mounting openings of the closing wheel frame. The inner races of the ball bearings are secured to the planter frame using threaded nut and bolt assemblies. The closing wheel frame is pivotal relative to the planter frame during normal operation by relative movement between the inner and outer races of the bearing. Variations of the mounting openings in the closing wheel frame are disclosed, including a tubular part, heavy washer or other annular structure welded to an outside surface of the closing wheel frame, or a bearing housing formed integral with the closing wheel frame.

Abstract: A tool holder for a power tool, in particular a drilling and/or hammering tool comprising a manually actuable sleeve (40) wherein components of the tool holder are held within the sleeve by a snap ring (100) which snap ring is fitted within the sleeve. The snap ring has at least one resilient arm (102) and the sleeve has a corresponding number of through holes (105) which extend to a radially outwardly facing surface of the sleeve, arranged such that the or each arm is engageable with a corresponding through hole in a snap fit. Each arm and through hole cooperate so that the portion (104) of the or each arm which can be viewed from the radially outwardly facing surface of the sleeve appears in the shape of a symbol. Thus, the snap ring (100) has the dual function of maintaining components, such as a locking ring (42) within the sleeve (40) and of providing an external indication to a user of how to actuate the sleeve.

Abstract: The present invention relates to a shaft-hub connection having an attachment flange and a clamping element, particularly a clamping ring, attachable thereto, by means of which the shaft end assigned to the attachment flange may be friction-locked to the attachment flange, with an interposed bushing which receives a slip torque. The present invention is based on the object of refining a device of the type initially cited in such a way that the lifetime of the attached components in the drivetrain is increased. This object is achieved according to the present invention in that the bushing is designed in multiple parts in the axial direction.

Abstract: The present invention provides a tent pole assembly for shoring up, which comprises a bottom pipe made of iron, a top pipe made of fiberglass reinforced plastic, and a connecting portion for connecting said bottom pipe and said top pipe. Said connecting portion is provided with a insertion portion and a protruding ring disposed along with exterior surface thereof. When said insertion portion inserts into one end of said bottom pipe, said protruding ring shores up said bottom pipe.

Abstract: A rivet system for use in motion furniture linkage and the like. The rivet system incorporates an electrically conductive plastic washer which eliminates the need for oil lubrication while maintaining the ability to electrostatically paint the linkage assembly.

Abstract: A bicycle assembly includes a frame portion, a component and a shim. The frame portion has a component mounting section. The component has a frame mounting section. The frame mounting section is removably coupled to the component mounting section by a fastener. The shim is mounted between the component mounting section and the frame mounting section on the fastener to space the component a predetermined distance from the frame portion. The shim includes a shim portion and a handle portion. The shim portion includes two shim sections connected together. The shim sections have free ends spaced from each other to form an open ended fastener opening with the fastener selectively received therein. The shim portion has a predetermined thickness in an axial direction of the fastener opening to space the component a predetermined distance from the frame section. The handle portion extends outwardly from the shim portion.

Abstract: An improved rivet system is disclosed. A wall proximity reclining/tilt chair includes the improved rivet system which eliminates the need for oil lubrication and additional bushings. The rivet system is such that installation is simplified and manufacturing inconsistencies are reduced. In this manner, the rivet system can be installed with less need for quality control confirmations.

Abstract: A pivot assembly is provided for attaching a closing wheel frame to a planter. The closing wheel frame has a pair of closing wheels attached at a rear end and a pair of mounting openings formed at a front end. The pivot assembly includes ball bearings having outer races fit loosely within each of the mounting openings of the closing wheel frame. The inner races of the ball bearings are secured to the planter frame using threaded nut and bolt assemblies. The closing wheel frame is pivotal relative to the planter frame during normal operation by relative movement between the inner and outer races of the bearing. Variations of the mounting openings in the closing wheel frame are disclosed, including a tubular part, heavy washer or other annular structure welded to an outside surface of the closing wheel frame, or a bearing housing formed integral with the closing wheel frame.

Abstract: A method of generating force between a structure and an additional member, particularly for reinforcing an existing structure so that an additional member can share existing load. Pre-cooled or pre-heated shims of shape memory alloy (SMA) are inserted between the additional member and the existing structure, or between different sub-units of the additional member, or between the additional member and shoes fixed for this purpose to the existing structure. On subsequent warming or cooling the SMA shims expand to apply compressive forces to the portions of the structure, additional member or shoe(s) with which they are in contact on their opposite sides. Further compressive, tensile, flexural or torsional forces will be developed within other parts of the structure and additional member as a result of the shim expansion depending on the particular arrangement.

Abstract: A device for fixing the hub of an arm of a wind-screen wiper (2) on a pivoting axis (1) with locking elements (6, 7) for the arm on the pivoting axis (1), a cavity (32) which is created in the hub (2) and is provided with adjusting and angular positioning elements for the arm in relation to the axis (1), whereby the hub (2) rests on the base of a stop (3) which nestles on a radius of operation (4) of the said axis (1); the locking elements (6, 7) are adapted in such a way that they can be engaged in a locking or unlocking position, the adjusting elements includes a connecting ring (10) which is rotationally fixed to the axis (1) and accommodated in the cavity (32) of the hub (2) with a certain amount of play allowing for limited relative angular displacement between the connecting ring (10) and the hub (2) when the locking elements (6, 7) are in an unlocked position, whereby all relative displacement is prohibited between the connecting ring (10) and the hub (2) when the locking elements (6, 7) are in a locke

Abstract: An opening and closing device includes a rotor pressed by a rotor spring and a reverse-rotor pressed by reverse-rotor spring, of which rotor cam and reverse-rotor cam are respectively placed at a certain position of stator cam. With this construction, rotor is urged in an opening direction in the opening condition and urged in a closing direction in the closing condition with respect to stator. A release cam pushes the reverse-rotor cam by moving a releaser along an axis, so that the device opens.

Abstract: A plant cutter apparatus has a tubular handling rod having a first end portion and a second end portion. A drive shaft extends through the handling rod and is mounted for undergoing rotation. A drive source unit is mounted on the first end portion of the handling rod for rotationally driving the drive shaft. A cutter blade is connected to the drive shaft for rotation therewith. A clutch case has a first mounting portion connected to the first end portion of the handling rod, a flexible coupling portion extending from the first mounting portion toward the drive source unit, and a second mounting portion extending from the flexible coupling portion and connected to drive source unit. The second mounting portion has an axial fitting hole for receiving the first end portion of the handling rod so that the first end portion of the handling rod is axially slid able therein.

Abstract: An adjunct part can be secured to a host part, where the host part defines a recess configured to allow a threaded fastener to secure the host part to a further part. The adjunct part has a resilient boss projecting therefrom and adapted to enter the recess, the boss having an axially extending opening to receive a threaded tightening member. The boss and the threaded tightening member have configurations which allow the tightening member, as it advances into the boss along the opening, to resiliently urge portions of the boss radially outward into binding contact with the interior of the recess, thereby fastening the adjunct part to the host part.

Abstract: A clamping device for a wire or cable (2), the end of which has to be attached in a housing (10) includes two clamping bodies (7, 8) with interacting conical surfaces. One clamping body (7) is arranged for receiving and passing through the cable (2), which has to be secured. The second clamping body (8) is arranged to exert pressure against the first clamping body for frictional securing of the cable. The clamping bodies are arranged in such a manner that when the tension in the cable increases the clamping bodies enclose the cable more tightly. The invention is particularly suitable for tools that have to be lowered into a well by the cable.

Abstract: A shock absorber for fifth wheel hitches for pickup trucks has a bushing embedded in memory polyurethane elastomer confined within a metal frame. The shock absorbers are mounted by brackets on the fifth wheel hitch support frame. The bushings receive pivot pins terminal to a cross beam mounting the couple assembly of the hitch. Both bushing and shock absorber frame have projections extending into the elastomer for better engagement. The projections can be studs or planar lugs. When the projections are loops of wire welded to the bushing and frame, the elastomer flows into the loops providing better engagement.

Abstract: In a preferred embodiment, a light weight telescope assembly for bicycles that is readily adjustable by riders in the field and that provides smooth action of the suspension system. This telescope assembly contains roller bearings to reduce stiction and prevent torsional losses. The adjustment mechanism includes an adjustable outer race shim composed of two oppositely tapered races moving longitudinally in relation to each other, thereby causing their combined thickness to expand or contract thus allowing the bearing pre-load to be adjustable. Integral with this adjustable pre-load mechanism is a bayonet-style collar whose design enables bearing pre-load adjustment from a position that is readily accessible by consumers. In addition, this collar enables greater geometric latitude on the shape of the inner tube, thereby enabling significant strengthening of the telescoping assembly using light weight materials and lower cost manufacturing processes that hitherto have been unachievable.

Abstract: A bar connection or splice and method uses a cage of relatively short bars which may be smaller reinforcing bars or threaded bars or rods. The bars of the cage may be joined by rings or wires and clamped to bridge or lap aligned bar ends. In one form, the concrete may be cast directly around to cage and bar ends to form the equivalent of a butt joined lap splice. In an enhanced form, the cage is included in a sleeve and set screws clamp the bars, cage and sleeve together. The sleeve may be filled with a hardenable matrix such as resin or grout, and then concrete is cast around the connection. The number of sets screws and bars of the cage may vary widely to form vertical and horizontal splices of axially aligned bar of the same or transitional sizes.

Abstract: The invention is based on a link joint with a first lever (10) which is constructed as a bent sheet metal part and which has, at one end, a trough (24) for receiving a bearing pin (14) and with a second lever (12) having a bearing eye (15) which encloses the bearing pin (14) and which has a bearing part (16) that is held between two stop surfaces (18, 20) arranged at its front sides. It is proposed that the bearing pin (14) has a hollow space (22) which is open at least toward a front side.

Abstract: The invention relates to a fixing device, comprising two clamping jaws (33) arranged symmetrically to each other and each having a through hole (38) for a rod (12) or shaft passing through same, and an actuating piston (27) which can be actuated by means of a fluid in a piston chamber. The fixing device also comprises an actuating lug (30) which can be moved by the actuating piston for engaging the clamping jaws and moving them away from each other against the force of a spring (36) and about a pivoting bearing (35) from a first into an open second position. The center of each through hole is at a first distance to the pivoting bearing and at a second distance to the area where each actuating lug engages each clamping jaw. The invention is characterized in that the second distance is smaller than the first distance.

Abstract: The invention relates to a coupling for coupling two rotatable bodies, in particular a gear and a drive shaft, which are disposed essentially concentric to each other, with or without axial offset, having a coupling part. In order to reduce the structural height of the coupling, the coupling part is integrated into one of the rotatable bodies. In a fuel-supply pump, the drive shaft is coupled to the driven gear by means of the coupling part.

Abstract: The present invention is for a device for mounting of wheels so that they may move in a preferably vertical direction at right angle to the wheel shaft. The invention is also standing board for prams having such wheel mounting. At its from end the standing board has a mounting means by which the standing board is pivotably mounted to the rear axle of a pram the main direction of movement of which is shown by arrow. The turning shaft of the wheel is mounted in a movable sleeve the movements of which are controlled both by a brushing which surrounds the sleeve and by a tube which is partially inserted into a groove in the sleeve. A spring is placed into the groove in the sleeve so that the spring contacts both the bottom of the groove and the end of the tube which penetrates the groove.

Abstract: A tolerance compensator provides a predetermined tolerance or space between connected assembly members. The tolerance compensator has a pair of connector components a first of which is secured to one of the assembly members and the second connector component is threadably installed, with a left hand thread, into the first connector component. A threaded fastener, with a right hand thread, is inserted into the connector components to initially engage the second connector component, either threadably or frictionally, to cause relative rotation between the first and second components whereby the second component advances toward and engages the second assembly member. The threaded fastener also threadably engages the first connector component to provide a secure connection between assembly members with the designed tolerance or space therebetween.

Abstract: An air compressor assembly includes a compressor, a motor, and a drive assembly operatively interconnecting the motor with the compressor. The compressor contains a piston in a cylinder. The motor has an output shaft. The drive assembly includes a flywheel and a bearing that supports the flywheel for rotation about an axis. A drive belt transmits torque from the output shaft to the flywheel so as to rotate the flywheel upon rotation of the output shaft. A linkage structure interconnects the flywheel with the piston so as to reciprocate the piston in the cylinder upon rotation of the flywheel. The drive assembly further includes a shaft extending along the axis between the flywheel and the bearing. A first end portion of the shaft is journaled in the bearing for rotation about the axis. A second end portion of the shaft is received within a bore in the flywheel with an interference fit between an outer surface of the shaft and an inner surface of the flywheel.

Abstract: A guide sleeve includes an outer bushing, which encloses an inner bushing with radial clearance, an elastic spring member made of an elastomeric material being arranged in gap created by the clearance, and inner bushing having at least one lubricant pocket open radially to the inside.

Abstract: One embodiment of the present invention is a device for attaching a polygonal baluster end to a handrail or base. This device includes a connector which is generally cylindrical. This connector also defines an internal axial channel having a polygonal cross-section. The axial channel is adapted to receive the polygonal baluster end.

Abstract: A connection structure of an electrical component is provided wherein the first connection member consists of liquid crystalline polymer synthetic resin. A weld joint is formed in the sleeve of the first connection member during the molding process. This weld joint permits the second connection member to be press-fitted into the first connection member by permitting the first connection member to fracture along the weld joint, thereby resulting in a tight connection between the first and second connection members.

Abstract: A wind tunnel blade (30) connected to a base (32) and held in position by a two-piece cuff (34). The wind tunnel blade (30) is formed in a resin transfer molding process in which central, fore, and aft foam core sections (70, 72, 74) are placed together to form the wind tunnel blade (30). Radius fillers (120) are used to fill the gaps between the outer edge of the foam core sections. The radius fillers (120) used in the wind tunnel blade (30) are formed by a braided sleeve (122) surrounding a number of unidirectional tows (124). A tip (68) is formed separately from the rest of the wind tunnel blade (30) and is glued to the top thereof. Stacked layers of braided fibers (100) are used to reinforce the central core section (70).

Abstract: A chair control mechanism for a chair assembly having a seat and a back includes an arrangement for mounting the lower end of a back support member, for positioning the back above the seat. The chair control mechanism includes a variable configuration mounting area so as to enable different back support members to be used with the same basic chair control mechanism structure. In one version, the variable configuration mounting area is provided by engaging one of a series of inserts within a transverse rear wall defined by the chair control mechanism. Each insert defines a passage configured to receive the lower seat mounting section of a back mounting member having a different set of dimensions, and the seat mounting section of the back mounting member extends through the passage and is engaged with the chair control mechanism by means of a fixed fastener-type arrangement or by a hand screw received within a slot for providing adjustability in the position of the back relative to the seat.

Abstract: A bicycle stem assembly comprising a bicycle stem having a novel ways for securing it to an unthreaded bicycle fork steerer tube, the novel means featuring a castellated bushing for pre-loading the upper bearing for the steerer tube and a clamp carried by the stem for selectively locking the stem and bushing to the steerer tube.

Abstract: In a device for reversibly locking a constant-velocity joint (2) with respect to a hub (1), the constant-velocity joint is axially locked to the hub by means of a spring-lock ring (21) of circular cross section recessed in a circumferential groove (22) in part formed on said joint (2) and in part on said hub (1). The joint comprises reaction means (24) integral therewith, particularly a rigid annular diaphragm disposed adjacent to the hub and facing an axial through bore (15) formed in the hub. The diaphragm is adapted for co-operation with an extraction tool (28) that can be inserted through the hub bore (15) in order to apply to the joint (2) and the spring-lock ring (21) an axial force with relative to the hub in either direction so as to separate or couple the joint (2) from or to the hub.

Abstract: For seating a rolling contact bearing ring in a housing or on a shaft, first and second grooves are formed in the cooperating periphery of either the rolling contact bearing ring or the housing or shaft. The first groove extends axially and is followed by the second groove that is inclined to form a conical surface at the rolling contact bearing ring. An intermediate ring is installed from the lateral entrance side of the bearing in the first groove and is plastically deformed, inclined into the second groove. A recess in the housing or shaft receives the deformed part of the intermediate ring. The remaining axial part of the bearing includes the diameter of the rolling contact bearing ring and of the cooperating housing or shaft that are the same diameter. The intermediate ring may include a flange that engages the entrance side of the bearing to position the intermediate ring. The intermediate ring may be the peripheral region of a pot-shaped cover over the entrance side of the bearing.

Abstract: A clamping joint between a universal joint spindle and a stub or wobbler of a rolling mill roll is formed by providing wedge members between the juxtaposed surfaces of the coupling box and roll stub and by bracing the wedge members by springs in the coupling head bracing the wedge members against a shoulder of the roll stub.

Abstract: A key washer for interlocking a pair of concentric parts is described. The key washer is comprised of a flat, metal ring having an outer circumferential edge and an inner circumferential edge. Two or more formations are formed in the inner circumferential edge and adapted to be received on a mating formation of an inner one of the concentric parts. The outer circumferential edge has a plurality of straight flat sections for mating engagement with a corresponding configured surface of an outer one of the concentric parts. The metal ring prevents rotation between the concentric parts. The washer is utilized in a preferred application for interlocking an aircraft turbine engine high pressure rotor assembly and a tie shaft nut.

Abstract: There is provided a structure for joining an impeller to a rotatable shaft, including (a) a bushing through which the impeller is joined to the rotatable shaft, the bushing including a hollow cylindrical portion which is to fit into a recess formed with the impeller and into which the rotatable shaft is to fit, (b) a first joint structure for joining the bushing to the impeller so that the bushing is positioned coaxially with the impeller, and (c) a second joint structure for joining the rotatable shaft to the bushing so that the rotatable shaft is positioned coaxially with the bushing. The structure provides a sufficient ability for transferring a torque between an impeller and a shaft, self-aligning performance between an impeller and a shaft, and good serviceability for assembling and disassembling, and further provides higher accuracy in axially positioning an impeller and a shaft and lower fabrication costs.

Abstract: A transition piece for use on tools of the type having a tool head with a socket to receive a tool handle. The transition piece includes a hollow cylindrical body and an annular skirt extending from the cylindrical body and encircling the body to define a recess for receiving the end of a tool head socket. A lower portion of the body is provided with slots to define a split end, and such insertion of a tool handle through the transition piece causes the split end to be biased radially outwardly into engagement with the tool head socket. In addition, the transition piece provides a smooth visual transition between the handle and the socket.

Abstract: The disclosed invention is an improved closing wheel attachment mechanism which has longer wear life than that of the typical attachment mechanism. The closing wheel arm on an agricultural planter has installed thereon an improved grease bushing assembly which has increased wear surface and the capability to utilize a grease on the surface. The combination of increased wear surface and greasing will greatly increase the operational life of the planter. Also included in the invention is the process and fixturing to incorporate the improved configuration on to an existing planter closing wheel structure. Included in this attachment mechanism is a welding jig which assures proper alignment of the improved bushing assembly.

Abstract: An expandable stop ring slides over the end of a top post until it engages a selected one of a number of spaced apart grooves in the end of a top post. The end of the top post is inserted into a bottom tubular post until the stop ring fits inside a keeper that is mounted to the upper end of the bottom post. The keeper prevents expansion of the stop ring, hence the stop ring and keeper combination support the top post and any equipment carried thereon. The top post height adjustment is made by lifting the top post to remove the stop ring from the keeper, thereby permitting sliding movement of the stop ring to another selected groove on the top post.

Abstract: A tap handle contains an attachment assembly to adjustably attach the handle to a tap spindle over a range of different axial positions relative to a closure member sealing an opening in a wall. The attachment assembly includes a locating member axially slidable within a bore of the handle to rotatably engage the spindle and a locking member which cooperates with the locating member to lock the locating member at a preselected axial position.

Abstract: Pins are arranged on the upper surface of a rotary case of a rotary connector for electrically connecting the steering wheel and the steering column of a vehicle by a flexible flat cable, while the steering wheel is provided on the lower surface thereof with coupling holes for respectively receiving a corresponding pin in order to securely hold the rotary case. Each of the pins is provided with an elastic silicon rubber cap. The elastic cap comprises a cylindrical main body and a plurality of elastic members extending longitudinally along the axis of the cylindrical section. When viewed from above, the elastic members show an arcuately curved and tapered profile projecting from the base toward the tip.

Abstract: An alignment device for power tools is disclosed comprising a power tool attachment, typically a socket or an extension and an alignment ring mounted on an output shaft. The alignment ring is placed between the output shaft and a socket or extension. The alignment ring reduces the motion between the socket and the output shaft, thereby reducing wear on both the socket and the output shaft. Also, the use of the alignment ring allows the energy of the tool to be used in improving torque.

Abstract: An acoustic ceiling compression strut system and method to help a suspended office building ceiling withstand an earthquake. The system includes two elongated tubes in a telescoping relationship and an adjustable locking connector placed between the two tubes and having a U-shape with two legs and a base. One tube is placed to abut a deck of the office building while the connector abuts the bottom of the tube. Thereafter, the second tube is lowered to abut a grid and the legs are bent around the top of the second tube thereby locking the two tubes and the connector and causing them to become a rigid strut.

Abstract: A modular support rail assembly that includes a rail having an open end with an internal wall surface and an elbow with facility at one end for mounting to a support, such as a building wall, and an opposing end with an internally threaded opening. An insert construction is disposed within the open end of the rail, and a fastener extends through the insert into the internally threaded opening in the elbow. An expansible ring is carried by the insert structure within the open end of the rail, and is responsive to compression of the insert structure upon tightening of the fastener to expand radially outwardly against and frictionally engage the internal wall surface of the rail. The rail is thereby firmly fastened to the elbow.

Abstract: A depth-adjustable steering column for a motor vehicle whose shaft is disposed in a tube body including two tubes (2, 3), one sliding in the other, a sheath (5) being disposed between the two tubes (2, 3). The sheath (5) comprises projecting elements which are flexible in a radial direction and come into contact with at least one of the tubes (2, 3). The projecting elements are orientated longitudinally, namely parallel to the axis of the tubes (2, 3).

Abstract: A structure for centering and connecting two members includes a first member having an engagement opening, and a second member having an engagement projection which has an outer peripheral surface substantially corresponding to an inner peripheral surface of the engagement opening. Small protrusions extend radially outwardly and are equidistantly disposed along a circumferential direction on the outer peripheral surface of the engagement projection. Straight notches are formed in the outer peripheral surface on both axial sides of each small protrusion to provide elasticity. When the engagement projection is fitted into the engagement opening, the small protrusions are elastically urged against the inner peripheral surface of the engagement opening. In this way, even when the two members have different thermal expansions, no play or no excessive stress is generated between the two members.