Interfacing surfaces of adjacent tiles in a downhole tool may combine to form a tortuous path therebetween. In various embodiments, this tortuous path may run generally parallel and/or perpendicular to a top surface of the tiles. One example of such a tortuous path may be created by a protrusion extending from an interfacing surface of one of the tiles that may fit snugly within a cavity receding into an interfacing surface of another of the tiles.

A tie rod that includes a central section, a first tapered section, and a second tapered section. A thermoplastic tube extends the length of the tie rod. The first tapered section includes a first insert positioned within the thermoplastic tube. The second tapered section includes a second insert positioned within the thermoplastic tube. A channel extends through the tie rod along the central section, the first tapered section, and the second tapered section.

A method may be employed to produce a variable-length steering shaft. The method may involve positioning a shaft core within a mold cavity of an injection molding tool coaxially with respect to a mold surface that delimits a toothing region, injecting molten plastic into the mold cavity between the shaft core and the mold surface of the mold cavity, removing a toothed shaft from the injection molding tool after the molten plastic has solidified, providing a hollow shaft and axially inserting the toothing region into an internal toothing of the hollow shaft. To make it possible to provide an improved sliding coating with the least possible manufacturing outlay, the injection of the molten plastic may be performed from one axial end region of the mold cavity.

An engine includes a crankshaft and a timing gear to be attached to the crankshaft so as to rotate integrally with the crankshaft. A fitting projection is provided on either one of the crankshaft and the timing gear, and a fitting recess to be fitted with the fitting projection, and erroneous-assembling prevention ribs to sandwich the fitting recess in a circumferential direction are provided on the other one of the crankshaft and the timing gear.

A composite tube may include a body having a longitudinal centerline axis and an end portion having a tapered section and an end rim. At least one of a radially outward edge and a radially inward edge of the end rim may be non-circular. The end rim may be circumferentially continuous. The end rim may be an undulating annulus. A joint assembly may include a support wedge that at least partially engages at least one of a radially inward surface of the end portion and a radially outward surface of the end portion of the composite tube.

A tube arrangement includes a composite tube defining a centerline axis, wherein the composite tube comprises a proximal surface and a distal surface, and an end fitting comprising a first end disposed within the composite tube and a second end extending from the composite tube, wherein an outer surface of the end fitting defines a flared portion defining a terminus of the first end, a lobe portion disposed axially from the flared portion, and a terminating portion disposed axially from the lobe portion, the proximal surface conforms to a geometry of the outer surface of the end fitting, the lobe portion and the flared portion mechanically lock the end fitting to the composite tube to mitigate movement of the end fitting relative to the composite tube.

Provided are a bearing assembly, a bearing assembly mounting structure and an air blowing apparatus. The bearing assembly includes: a bearing sleeve including an inner assembling face, and a bearing mounted into the bearing sleeve from an axial side of the bearing sleeve and including an outer assembling face corresponding to the inner assembling face. The inner assembling face and/or the outer assembling face is provided with a supporting structure protruding toward an opposing assembling face and cooperating with the opposing assembling face in a contacting manner, and the supporting structure is symmetrically disposed in a peripheral direction of the assembling face where the supporting structure is located.

A connecting rod is provided, which includes a rod shaft and a rod cap. The rod shaft and the rod cap can be releasably fastened through connecting means to form a connected state, and when the rod shaft and the rod cap are in the connected state, they form a rod eye configured to enclose a bore for mounting the connecting rod on a crank shaft. The rod shaft and the rod cap have contact surfaces at which they touch each other in the connected state. The contact surfaces have an interlocking section-wise serration, and the contact surfaces have an un-serrated section.

A connecting rod structure includes a first rod, a second rod and a locking element. The first rod includes a first rod portion, a first and a second limiting portion. The first and the second limiting portion extend from a side of the first rod portion, and are spaced apart. The first limiting portion has a first through hole, and the second limiting portion has a second through hole. The second rod includes a second rod portion and a positioning portion. The positioning portion has a through groove, and is located between the first and the second limiting portion. An inner diameter of the through groove is greater than that of the first and the second through hole. The locking element passes through the first through hole, the through groove and the second through hole, to lock the first rod and the second rod together.

A method of assembly of a drive shaft comprising providing a tubular member 12 of composite material form, fitting a collar 24 of composite material form to an exterior of an end part of the tubular member 12 to inwardly compress the end part of the tubular member 12, and subsequently press fitting part 14a, 16a of an end fitting 14, 16 into the interior of the end part of the tubular member 12. A drive shaft 10 manufactured in this manner is also described.