Abstract: An articulating ball joint for connecting a pair of driven members to a driving member such as a crank pin. In one embodiment, a single ball is held in a first, or inner, socket defined by a coupling member having a convex outer surface, and the first socket is held within a second, outer, socket defined in a second coupling member also having a convex outer surface, which is, in turn, engaged by a retainer.

Abstract: In a motor, a gear housing of a speed reducer is connected to a motor unit. A worm is received in the gear housing and is rotated by rotation of a rotatable shaft of the motor unit. A worm wheel is received in the gear housing and is meshed with the worm. An output shaft is fixed to a center part of the worm wheel. The worm wheel includes a receiving recess, which is axially recessed in a center part of the worm wheel. An axially inner part of a bearing, which rotatably supports the output shaft, is received in the receiving recess.

Abstract: The invention relates to a wiper blade (1) that comprises a bearing structure (20) in which a flexible vertebra (23) is longitudinally inserted and on the sides of which are formed openings (25a, 25b, 26a, 26b, 27a, 27b) exposing the side edges (23a) of the vertebra (23), as well as a connector (50) that is fitted substantially transversally onto the bearing structure (20) at the level of the openings (25a, 25b, 26a, 26b) and that is blocked in terms of movement in the fitting direction thereof by the portions of the side edges (23a) protruding from said openings (25a, 25b, 26a, 26b). The invention is characterised in that the connector (50) includes at least one deformation (70a) extending inside a notch (71a) formed in the vertebra (23) at a portion of a side edge (23a) and accessible via an opening (27a).

Abstract: The invention provides for a wiper arm for a windshield wiper system comprising a fixing element (12) for connection to a drive shaft, whereby a tiltably-fixed cover unit (24) is provided for at least partially releasing the fixing element (12). It is proposed that the cover unit (24) can be engaged with the fixing element (12) in the tilted position. A cover unit for a wiper arm is also proposed.

Abstract: A swing lever is fixed to a pivot shaft to pivot the pivot shaft about a pivot axis thereof. A wiper arm is directly connected to a distal end portion of the pivot shaft and is pivoted together with the pivot shaft about the pivot axis of the pivot shaft when the pivot shaft is driven by the swing lever. The wiper arm is pivotable about a pivot axis thereof, which is generally perpendicular to or is tilted relative to the pivot axis of the pivot shaft, toward or away from a wiping surface. A coil spring is directly or indirectly connected between the wiper arm and the swing lever to exert an urging force to urge the wiper arm toward the wiping surface in a wiping operational position of the wiper arm for wiping the wiping surface.

Abstract: A wiper system for a vehicle includes a frame supported by the vehicle and a wiper motor supported by the frame. The wiper system further includes a wiper arm coupled to the wiper motor and configured to be driven by the wiper motor to move in a reciprocating pattern. A water blocking member is wrapped around a portion of the frame to prevent water running along the frame from reaching the wiper motor. The blocking member is flexible and has separate free ends to enable assembly with the frame. A method of assembling the wiper system includes pressing the water blocker onto the frame at a location away from spaced apart ends of the frame.

Abstract: In a vehicle windshield wiper system, a support base includes a connecting rod (9) fixedly attached to a vehicle body and extending across a width of the vehicle body, and a base member (10, 11) depending from an intermediate part of the connecting member. A wiper motor (2) attached to a lower surface of a horizontal wall portion (11) of the base member, and a crank arm (3) is attached to an output shaft of the wiper motor. The base member is formed with an opening (13) to avoid an interference with the crank arm as the crank arm undergoes the rotative movement. The opening in the support base prevents an interference with the movement of the crank arm, and this allows the crank arm and an associated link mechanism (6) to be placed opposite to a vertically intermediate part of the support base, and immediately adjacent to the support base. Therefore, the windshield wiper system can be accommodated in a readily available space (24) under the lower edge of the windshield.

Abstract: A location space in an engine compartment is made smaller. A DR-side wiper motor and an AS-side wiper motor are arranged within a projection area of a windshield into a cabin of a vehicle in comparison with a DR-side pivot holder and an AS-side pivot holder. Therefore, a location space of each wiper apparatus inside an engine compartment can be made smaller, and can further improve a degree of freedom of design on a vehicle side.

Abstract: A disengageable arrangement for connecting a windscreen-wiper arm to a drive shaft driven in rotation about its longitudinal axis has a device solidly attached to the arm and providing the connection of the arm, and the drive shaft in the normal operating position of the windscreen wiper. The device is deformable under an effect of a torque applied to the arm greater than that exerted by said drive shaft, and is capable of being placed back in the normal operating position by locked relative positioning of the arm and the drive shaft. There is a single locked relative position of the arm and the drive shaft. The deformable device has at least two stacked elastic blades. The ends of each stacked elastic blade solidly are attached to the arm. Each of the at least two stacked elastic blades has a locking part inserted in a stopping part solidly attached to the drive shaft.

Abstract: A rotation control mechanism including a primary shaft driven in an alternating axially rotating manner, a drive carrier fixed to the primary shaft, a secondary shaft mounted in an axially rotatable manner in relation to the drive carrier, a fixed cam provided with a specific profiled element, and a control element which is fixed to the secondary shaft and cooperates in a sliding manner with the cam profiled element during the displacement of the drive carrier in relation to the fixed cam, where the sliding of the control element along the cam profiled element control the axial pivoting of the secondary shaft.

Abstract: A wiper arm assembly and method of construction thereof includes a mounting head and a wiper arm configured for relative rotation during assembly from a disassembled position to a shipping position, wherein the wiper arm and mounting head are locked against rotation toward the disassembled position once in the shipping position. The mounting head and wiper arm have locking surfaces configured for locked engagement with one another while in the shipping position. The locking surfaces are brought into engagement with one another by a force imparted by a spring while rotating the mounting head relative to the wiper arm from the disassembled position toward the shipping position. When in the shipping position, the locking surfaces confront each other and prevent the mounting head and the wiper arm from rotating back toward the disassembled position from the shipping position.

Abstract: A motor bracket to which a wiper motor is fixed, and a DR side pivot holder are coupled together by means of a DR side pipe frame inclined to a plane perpendicular in the axial direction of an output shaft of a wiper motor, and the motor bracket and an AS side pivot holder are coupled together by means of an AS side pipe frame inclined to the plane perpendicular in the axial direction of the output shaft. An output arm is fixed to the output shaft of the wiper motor, and the output arm is disposed between the DR side pipe frame and the AS side pipe frame, and between the connecting rod for coupling a DR side lever and an AS side lever, and the motor bracket.

Abstract: The invention starts with a windshield wiper device (10), in particular for a motor vehicle, with at least one drive element (16) that can be fastened to the vehicle body (26) and that has a driven shaft (28) and at least two axially rigid fastening elements (22), which engage in receiving openings (24) on the vehicle body (26) and are provided with at least one damping element (76, 90, 96) for damping mechanical vibrations.

Abstract: A windscreen wiper arm, particularly for automobiles, comprising a mounting head on a drive shaft and an arm member pivotally connected to the mounting head by means of a pivot pin, wherein the arm member has a substantially U-shaped cross-section near said pivot pin comprising two side walls, wherein a part of the mounting head extends between the side walls and beyond said pivot pin, and wherein a spring is hooked with its first end on a pin on the mounting head, with the special feature that said spring is hooked with its second end on the arm member.

Abstract: In a motor, a gear housing of a speed reducer is connected to a motor unit. A worm is received in the gear housing and is rotated by rotation of a rotatable shaft of the motor unit. A worm wheel is received in the gear housing and is meshed with the worm. An output shaft is fixed to a center part of the worm wheel. The worm wheel includes a receiving recess, which is axially recessed in a center part of the worm wheel. An axially inner part of a bearing, which rotatably supports the output shaft, is received in the receiving recess.

Abstract: A windshield wiper device (10), in particular, for a motor vehicle, includes a wiper bearing (14), which includes a bearing housing (24), a wiper shaft 922), which is supported in the bearing housing (24) and which supports a wiper arm (28) on a first end (26), and an element (42) that axially secures the wiper shaft (22). The element (42) includes at least one region that is made from a foam material.

Abstract: A wiper arm pivot is rotatably mounted in a pivot holder fixedly securable to vehicle structure. The wiper arm pivot is telescopingly displacable in the pivot holder upon an impact load on one end of the wiper arm pivot. An energy absorption material has a gel state when disposed in the pivot holder and flows through one or more orifices from the pivot holder under impact forces causing telescoping movement of the pivot in the pivot holder absorption of the impact force on the pivot shaft. In another aspect, the energy absorption material is a liquid which is retained within the pivot holder by a releasable plug which is separable from the orifice under a predetermined impact pressure.

Abstract: A mounting part of a windshield wiper, having a receiving opening for a wiper shaft at one end, and forming a part of a fold-away hinge at the other end, and being formed from a flat sheet metal by deep-drawing, punching and bending and having a u-shaped cross-section profile and a spring mount. The spring mount is formed by deep-drawing from a sidewall of the u-shaped cross-section profile.

Abstract: The invention relates to a windscreen wiper device comprising an arm (1) mounted in such a way that it can pivot about a first axis (3) on a driver (2) which is rotationally actuated within an angular range by means of the shaft (5) of an axis which is substantially parallel to the first axis (3), comprising means for limiting the extent of pivoting in a direction opposite to a surface that is to be wiped, consisting of an arm part and a driver part which acts as a stop when the arm (1) is pivoted from a specific angle. According to the invention, said driver part is a washer (6) which is mounted on said shaft (5) and is integral with the driver (2) and is provided with a stop means for said arm part.

Abstract: A wiper arm window latch system and method includes an end of a wiper arm which is mounted on a window and which is received in a drive coupler coupled to a drive motor mounted on a door. The drive coupler permits the wiper arm to be drivingly coupled to a wiper motor. The drive coupler and end of the wiper arm also cooperate to lock the wiper arm to the drive coupler, thereby causing the window of the vehicle to be locked in a closed position, such as against the door. This system and method is particularly suited for use in a vehicle having a rear window which is pivotable between an open position and a closed position and where a rear window wiper is desired or required.

Abstract: An energy absorbing wiper system for a vehicle, including: a pivot shaft to which a wiper arm is fixed; a pivot shaft holder into which the pivot shaft is rotatably inserted; an impact absorbing portion provided between the pivot shaft and the pivot shaft holder, the impact absorbing portion being adapted to be broken or deformed when a certain load is applied thereto to thereby permit the movement of the pivot shaft in a sinking direction relative to the pivot shaft holder; and, an energy absorbing member interposed between the wiper arm and the pivot shaft holder, the energy absorbing member adapted to be broken or deformed while permitting the sink of the pivot shaft when the pivot shaft moves in the sinking direction after the impact absorbing portion has been broken or deformed, to thereby absorb the moving energy of the pivot shaft.

Abstract: A wiper assembly for use in vehicles is provided, including a shaft which is connected to a driving motor via a linkage and rotated by the driving motor, an arm head including a shaft hole into which the shaft is inserted, an arm having one end combined with the arm head by a rotating shaft and rotatable about the rotating shaft and the other end combined with a wiper blade which wipes a window of a vehicle, a locking member which is supported by the arm head and movable between a locking location where the locking member is locked in the shaft so that the shaft cannot be separated from the shaft hole of the arm head and an unlocking location where the locking member is unlocked from the shaft so that the shaft can be separated from the shaft hole of the arm head, and a locking member moving unit which moves in gear with a rotation of the arm so as to move the locking member between the locking location and the unlocking location.

Abstract: A drive mechanism 10 for a windshield wiper has a pivot 11 with a first end with an internally threaded hole 22 for receiving a screw 23 for securing a wiper arm. The first end has a coupling surface 24 adapted to mate with a DIN style wiper arm attachment. A ring driver 25 is fitted to the end of the pivot and mates with the coupling surface 24. The driver has an outer surface 27 adapted to mate with a US style wiper arm attachment.

Abstract: A windshield wiper includes a drive shaft (10), to which shaft a crank (12) is fastened. A base body (14) of the drive shaft (10) is made from an extruded light metal profile and on its free end, in the region of a fastening part, carries a connection part (16, 22) of a harder material, which has a screw thread (18).

Abstract: A wiper arm window latch system and method includes an end of a wiper arm which is mounted on a window and which is received in a drive coupler coupled to a drive motor mounted on a door. The drive coupler permits the wiper arm to be drivingly coupled to a wiper motor. The drive coupler and end of the wiper arm also cooperate to lock the wiper arm to the drive coupler, thereby causing the window of the vehicle to be locked in a closed position, such as against the door. This system and method is particularly suited for use in a vehicle having a rear window which is pivotable between an open position and a closed position and where a rear window wiper is desired or required.

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: A four-jointed wiper arm assembly includes a drive lever, which is connected to a driveshaft so that they rotate together and is coupled via a coupling element to a link rod which is pivotably mounted in a bearing on a vehicle body. The drive lever encloses an angle of approximately 90° with the coupling element in a parking position of the windshield wiper and is adjustable about an adjustment axis which extends approximately parallel to the coupling element and intersects the longitudinal axis of the driveshaft, and the coupling element is connected to the link rod via a ball joint.

Abstract: A lightweight windshield wiper installation system is provided wherein the system includes a re-usable mounting device in combination with a lightweight windshield wiper assembly which does not require a connecting member. The mounting device includes a mounting arm having a first end and a second end, a first retaining means, a second retaining means. The lightweight windshield wiper installation system may further include an arm linkage, and a release handle. The mounting arm is operative to position a lightweight windshield wiper system onto a vehicle which is removably attached to the mounting arm via the first retaining means and the second retaining means. The release handle cooperates with the first retaining means and the second retaining means via an arm linkage to hold and release the lightweight windshield wiper system.

Abstract: The invention relates to a wiper apparatus in which a pair of pivot axes are provided, one pivot axis at the central portion and the other pivot axis one side portion in the left and right direction of the window surface. In the invention, wherein the rod rush angle formed by a link arm, which rotates the pivot axes clockwise and counterclockwise, and a link rod can be made as small as possible. The second pivot axis at one side portion is disposed so that the plane, including the swinging locus, of the second link arm, that is coupled to the corresponding second pivot axis, and the axial line of the second link rod, in the lengthwise direction, are made roughly parallel to each other.

Abstract: A wiper arm including a securing member and a hinge member coupled thereto via a hinged joint, and a cover cap affixed to the securing member and having a cover wall and side walls laterally contiguous thereto which cover the securing member. Adjacent to the cover cap toward the hinge member is a movable hinge cap which is coupled to the hinge member and covers the hinged joint, while it is guided on the securing member and the cover cap, respectively, in a manner that it is able to swivel and is movable in longitudinal direction.

Abstract: An arm head has a couple of hinge holes. A cover has a couple of hinge projections. The arm head and the cover are hingedly connected to each other through the hinge holes and the hinge projections. A rotation guide extends radially outwardly from each hinge hole. A protrusion protrudes radially outwardly from each hinge projection and is received in the rotation guide. A locking projection extends from the rotation guide. The locking projection is spaced from an opening movement limiting end of the rotation guide for a distance, which is substantially the same as a width of the protrusion of the hinge projection.

Abstract: In a wiper arm, a head cover detachably attached to an arm head has a stopper wall that protrudes inward from an end thereof and is inserted into a gap between the arm head and an arm member. When the arm member is rotated by a certain angle to the arm head in the direction away from the windshield glass, the stopper wall comes in contact with the arm member so that further rotation of the arm member is suppressed. Accordingly, a possible damage of the wiper arm due to a car washer, which accidentally turns the arm member to the lock back state, is avoided. On the other hand, if a user detaches the head cover from the arm head, the arm member can be manually rotated to the lock back state so that a blade rubber replacement operation for a maintenance purpose is easy.

Abstract: The invention proposes a motor vehicle windscreen wiper of the type in which a cover (10), intended completely to cover over a drive head, includes two longitudinal lateral flanks (16) joined together by a transverse back (18) which includes an upper longitudinal part (24) and a downwards-curved part (86) at its rear end. The transverse back of the cover (10) includes an aperture (14) giving access to means for fixing the drive head onto the end of an alternating-sweep drive shaft. A cap (12) is provided, the contour (44, 46, 48) of which is complementary to that (30, 32, 34) of the aperture (14), which is mounted articulated (50, 60) on the cover (10) between a service position in which it blocks off the aperture (14) and an open raised position in which the aperture (14) is clear.

Abstract: The invention proposes a motor vehicle windscreen wiper of the type in which a cover, intended completely to cover over a drive head, includes two longitudinal lateral flanks joined together by a transverse back which includes an upper longitudinal part and a downwards-curved part at its rear end. The transverse back of the cover includes an aperture giving access to means for fixing the drive head onto the end of an alternating-sweep drive shaft. A cap is provided, the contour of which is complementary to that of the aperture, which is mounted articulated on the cover between a service position in which it blocks off the aperture and an open raised position in which the aperture is clear.

Abstract: A crushable windshield wiper pivot is provided. The crushable wiper pivot includes a pivot base, a hollow sleeve, and a cap. The pivot base is driven by a windshield wiper motor and adaptable to reciprocate the windshield wiper arm and its components across the windshield. The pivot base is disposed partially in a vehicle cowl. The hollow sleeve includes a first end mounted on the pivot base, a middle section adaptable to crush outwardly and vertically, and a second end. The cap of the present invention is mounted on the second end of the hollow sleeve. The cap has a surface adaptable to mate with a base of a wiper arm whereby the cap is vertically displaced and the hollow sleeve crushes outwardly and vertically at the middle section when subjected to a pedestrian impact.

Abstract: The invention is a wiper arm (20) for securement to a drive shaft (10,12). The wiper arm (20) has a securing part (18), which on one end has a bearing point (16) by way of which the wiper arm can be connected, in a manner fixed against relative rotation, to the drive shaft (10, 12) via a nut (14). The nut can be screwed onto the drive shaft (10,12). The nut is formed by a component integrally cast onto the securing part (18) and is connected to the securing part (18) via a binding (26) that can be released upon installation of the wiper arm (20).

Abstract: A wiper arm for a pivotably connected wiper blade has a fastening part (10) for fastening to a drive shaft (12), by inserting the drive shaft through a widening indentation (38) of the fastening part (10), and a screw nut (44 tenses the fastening part (10) against a bearing face (30) to the drive shaft (12) via a clamping part (40, 50) that is adapted to the indentation (38), and also the contact face (66) between the clamping part (40, 50) and the fastening part (10) forms a part of the surface of a sphere, and the bearing face (30) forms a part of a jacket face of a cylinder, whose cylinder axis (32) extends through the center point (36) of the sphere and parallel to the longitudinal direction (34) of the wiper blade.

Abstract: The present invention is based on a wiper arm (10) having a securing member (12) and a hinge member (14) coupled thereto via a hinged joint (16), a cover cap (46) being affixed to the securing member (12) and having a cover wall (48) and side walls (50) laterally contiguous thereto which cover the securing member (12).

Abstract: An arm head has a couple of hinge holes. A cover has a couple of hinge projections. The arm head and the cover are hingedly connected to each other through the hinge holes and the hinge projections. A rotation guide extends radially outwardly from each hinge hole. A protrusion protrudes radially outwardly from each hinge projection and is received in the rotation guide. A locking projection extends from the rotation guide. The locking projection is spaced from an opening movement limiting end of the rotation guide for a distance, which is substantially the same as a width of the protrusion of the hinge projection.

Abstract: The invention is based on a fastening element for a wiper arm, which on one end has a first fastening region (12) with a conical hub (14) and on another end has a second fastening region (18) with a bearing point (20). It is proposed that the fastening element comprises a middle, longitudinally extending, prefabricated carrier part (22), and the fastening regions (12, 18) are formed by separate heads (24, 26) cast onto two ends (10, 16) of the carrier part (22).

Abstract: In a wiper arm, a head cover detachably attached to an arm head has a stopper wall that protrudes inward from an end thereof and is inserted into a gap between the arm head and an arm member. When the arm member is rotated by a certain angle to the arm head in the direction away from the windshield glass, the stopper wall comes in contact with the arm member so that further rotation of the arm member is suppressed. Accordingly, a possible damage of the wiper arm due to a car washer, which accidentally turns the arm member to the lock back state, is avoided. On the other hand, if a user detaches the head cover from the arm head, the arm member can be manually rotated to the lock back state so that a blade rubber replacement operation for a maintenance purpose is easy.

Abstract: A crushable windshield wiper pivot is provided. The crushable wiper pivot includes a pivot base, a hollow sleeve, and a cap. The pivot base is driven by a windshield wiper motor and adaptable to reciprocate the windshield wiper arm and its components across the windshield. The pivot base is disposed partially in a vehicle cowl. The hollow sleeve includes a first end mounted on the pivot base, a middle section adaptable to crush outwardly and vertically, and a second end. The cap of the present invention is mounted on the second end of the hollow sleeve. The cap has a surface adaptable to mate with a base of a wiper arm whereby the cap is vertically displaced and the hollow sleeve crushes outwardly and vertically at the middle section when subjected to a pedestrian impact.

Abstract: A wiper arm that can be pivoted out of the way, in particular for motor vehicles, having a fastening part (2) and a hinge-part (3), which are joined together via a wiper arm hinge (4) in such a way that the hinge part (3) can be pivoted out of the way about the wiper arm hinge (4), thereby reaching a locking means (14), and further having a tension spring (8) and a hoop spring (9), wherein the hoop spring (9) has clamping segments (9.3, 9.4), and that the fastening part has an extension (13) with bearing faces (14.1, 14.2), on which the clamping segments (9.3, 9.4) of the hoop spring (9) rest in the position pivoted out of the way of the hinge part (3).

Abstract: A wiper device for a vehicle disclosed is provided with a wiper motor, a wiper pivot connected to the wiper motor, and a pivot holder having a base portion attached to the vehicle body and a bearing hole pivotally supporting the wiper pivot in a rotatable manner. Here, the wiper pivot can rotate around the pivot axis thereof by using a drive force from the wiper motor and has a cutout portion, and the wiper pivot extends so as to project toward an outer side of the vehicle body. In such a structure, it is further structured such that a C ring engaged with the cutout portion of the wiper pivot is released from the cutout portion when a load equal to or more than a predetermined value acts on the wiper pivot. In this case, as a result, the wiper pivot is moved to an inner side of the vehicle body.

Abstract: In a windshield wiper drive assembly having a pivot shaft and housing for passage through an aperture formed in a panel of a vehicle, a seal is provided formed as a unitary one-piece cap and seal body. The one-piece body has a cap with a longitudinally extending aperture engageable at one end with the housing and at another end with the pivot shaft. An integrally formed seal portion is provided to be engaged with the panel of the vehicle after installation. The cap has an enlarged portion for snap-fit with respect to the housing, and a reduced portion for sealing engagement with the pivot shaft. The sealed portion extends radially and longitudinally from an inner edge adjacent an outer longitudinal edge of the enlarged portion of the cap toward an outer edge adjacent an outer longitudinal edge of the reduced portion of the cap. The seal portion can extend beyond the outer longitudinal edge of the reduced portion of the cap.

Abstract: A motor vehicle wiper comprising a driving head designed to be fixed to a free upper end of a wiper driving shaft at a bore includes a wiper arm, which is articulated on the driving head by a rear longitudinal end around a transverse axis which is substantially perpendicular to the general longitudinal direction of the wiper and perpendicular to the driving shaft axis, between a raised position and an operative position toward which it is returned by a helical compression spring inserted between the driving head and a support surface of the arm, the helical compression spring extends around the bore.

Abstract: A wiper bearing has a bearing shell and a shaft, which is received by the bearing shell and is connected at one point to a drive mechanism and has a receptacle for wiper arm. The bearing shell concentrically grips a region of the shaft and forms a first axis, which forms an angle with a second axis that extents through a region having a receptacle of the shaft.

Abstract: A pivot structure for a vehicle wiper device is provided. The pivot structure prevents foreign matters from invading through a body exterior sheet into a dash board area, for example. The pivot structure may be used in both left-side-drive vehicles and right-side-drive vehicles. A first regulating rib and second regulating rib are formed on respective fixing pieces, which extend from the outside periphery of a pivot holder. The first and second ribs are formed symmetrically with respect to an imaginary line X passing through the center axis of the pivot shaft on the right side and the left side.