Abstract: A coil spring is disposed in a fluid passage between a cylindrical body and a valve element to urge the valve element toward a closed position. The coil spring comprises a valve support portion supporting the valve element, a secured portion secured to an inner peripheral surface of the fluid passage, an expanding-contracting portion extending from the secured portion, and a connecting portion between the expanding-contracting portion and the valve support portion. The connecting portion comprises a first portion curved so as to pass radially outward of an end winding portion of the expanding-contracting portion, a second portion passing through the center of the valve support portion, a third portion extending curvedly so as to overlap the first portion, and a fourth portion extending to the valve support portion. When the coil spring is compressed, the valve support portion is supported to the expanding-contracting portion 54 through the connecting portion.

Abstract: A drive arrangement for a motor vehicle functional part includes: a housing, in which a drive motor, a gear mechanism and an adjustor are provided at least partially; a drive shaft configured to transfer the adjustor via the gear mechanism from a closed position into an open position and vice versa; and a wrap spring arrangement comprising two wrap spring members, which act in opposite directions. The wrap spring arrangement is arranged on a gear mechanism output side, in a region of the adjustor.

Abstract: A clutch apparatus is equipped with two clutch structures having a clutch drum therein. A driven plate and a piston are provided in the clutch drum of each clutch structure, and a primary coned disc spring and a secondary coned disc spring, which are ring-shaped, are provided between the driven plate and the piston. A flat portion 12 is formed on an inner peripheral portion of a convex surface of the primary coned disc spring 1, and the flat portion 12 can come into contact with a counter member first when a load is applied. A load in a flat condition due to elastic deformation is adjusted by the flat portion so as to be a desirable value. Blanks 1A and 2A of the primary coned disc spring and the secondary coned disc spring can be obtained from one sheet of material having the same thickness. In this case, the flat portion 12A is formed by press forming on an inner peripheral portion of the blank 1A in view of the shape thereof after bending forming is performed.

Abstract: A manufacturing method of a coil spring for an automobile suspension includes forming a material into a coil shape; performing a heat treatment step on the material; performing a warm shot peening step on the material, and performing a hot setting step on the material. By performing the warm shot peening step prior to the hot setting step, a stronger compressive residual stress is imparted in a direction along which a large tensile stress acts during actual use of the coil spring, thereby improving sag resistance and durability of the coil spring. A coil spring is also manufactured according to this method.

Abstract: A gas spring and gas damper assembly can include a gas spring and a gas damper. The gas spring can include a first end member, a second end member and a flexible wall that at least partially form a spring chamber. The gas damper can include first, second and third damper elements that are telescopically interconnected with one another. The first and third damper elements can be operatively connected to respective ones of the first and second end members. The third damper element includes damper piston having an axial clutch. The second damper element is suspended between the first and third damper elements by biasing elements that engaging the damper piston.

Abstract: A method of increasing oil pressure in a heavy duty truck engine lubricating system is provided. The lubricating system comprises an oil pressure regulating assembly mounted in an oil filter base and having a main spring to regulate oil pressure, and a high pressure relief valve assembly mounted in the oil filter base and having a peak clipping spring to relieve oil pressure when the pressure exceeds a specified limit. The method includes the steps of replacing the main spring with a replacement main spring having a higher spring constant and replacing the peak clipping spring with a replacement peak clipping spring having a higher spring constant. A replacement kit for increasing oil pressure is also provided.

Abstract: A vehicle seating system includes a top frame for mounting to a vehicle seat. The top frame has integral rails or channels with roller tracks at one end and vibration dampening systems at the other. An opposing pair of the roller tracks includes a vibratory dampening or regulation system that controls the amount of fore and aft travel of the top frame.

Abstract: A vehicle differential unit (DU), including: a torsional damper assembly having a plurality of independently sprung damper assemblies positioned with respect to the DU, each damper assembly configured to reduce noise or vibration generated by the DU in a predetermined frequency range.

Abstract: An electromagnetic clutch with improved transmission torque by means of a low-cost method includes an electromagnetic coil, a rotor that is rotary driven by means of an external drive source, an armature attracted to the rotor by means of a magnetic force of the electromagnetic coil, and a hub structure. The electromagnetic clutch is characterized in that a recessed and projected surface having a surface roughness of 10 ?m or more and a hardness of 4 GPa or less is formed on the friction surface of the rotor and/or the friction surface of the armature.

Abstract: A flexible spring member includes a flexible wall that is at least partially formed from an elastomeric material The flexible wall can have a longitudinal axis and extend peripherally about the axis and longitudinally between first and second ends. The flexible wall can also include an outside surface and an inside surface that can at least partially define a spring chamber. A radial-biasing band can be disposed along the outside surface of the flexible wall in longitudinally-spaced relation to the first and second ends. The radial-biasing band can be at least partially formed from an elastomeric material and can be operative to elastically bias at least a portion of the flexible wall in one of a radially-inward direction and a radially-outward direction in an inflated condition of the gas spring assembly. A gas spring assembly and a method of manufacture including such a flexible spring member are also included.

Abstract: Disclosed are a pad spring for disc brakes wherein the surface of the pad spring is roughened through the use of a sanding device using a basket, thereby increasing adhesive force of a coating material coated on the pad spring, and a manufacturing method thereof.

Abstract: A railcar draft gear assembly including a housing, a spring sea, a spring and a friction clutch assembly in operable combination relative to each other within the housing. The spring includes a series of axially stacked elastomeric pads arranged between a closed end of the housing and the spring seat. An axially elongated guide rod is endwise passed through the spring seat and elastomeric pads for aligning the pads relative to a longitudinal axis of the draft gear assembly. The guide rod is operably inhibited from axial shifting movements during operation of the draft gear assembly. A related method for assembling the draft gear is also disclosed.

Abstract: Lateral support elements for engaging an associated flexible wall of an associated gas spring assembly can be displaceably mounted along an associated end member of the associated gas spring assembly, such as by way of an elastomeric mounting element. The elastomeric mounting element can be formed as an endless annular ring, from an elongated length of elastomeric material wound helically about an axis, a plurality of support element sections disposed in peripherally spaced relation to one another about an axis or from a plurality of concentric element rings formed from elastomeric and comparatively rigid materials. Gas spring assemblies including one or more of such lateral support element as well as suspension systems that includes one or more of such gas spring assemblies and methods of manufacture are also included.

Abstract: An assembly includes a flexible wall, that can at least partially define a spring chamber for containing pressurized gas. The flexible wall can include at least one mounting bead formed along an end thereof. A compression core can be disposed along the exterior of the flexible wall in abutting engagement with the mounting bead. The compression core can be captured between the mounting bead and a portion of the flexible wall such that inflation of the spring chamber biases the flexible wall, mounting bead and compression core outward and into engagement with an end member to form a gas spring assembly. A suspension system and a method of assembly are also included.

Abstract: A clutch apparatus is equipped with two clutch structures having a clutch drum therein. A driven plate and a piston are provided in the clutch drum of each clutch structure, and a primary coned disc spring and a secondary coned disc spring, which are ring-shaped, are provided between the driven plate and the piston. A flat portion is formed on an inner peripheral portion of a convex surface of the primary coned disc spring, and the flat portion can come into contact with a counter member first when a load is applied. A load in a flat condition due to elastic deformation is adjusted by the flat portion so as to be a desirable value. Blanks and of the primary coned disc spring and the secondary coned disc spring can be obtained from one sheet of material having the same thickness. In this case, the flat portion is formed by press forming on an inner peripheral portion of the blank in view of the shape thereof after bending forming is performed.

Abstract: A handlebar is described, including a handlebar tube having a middle portion and two rising portions disposed on opposite sides of the middle portion. A damping device may be spaced from the middle portion and may span from one rising portion to the other rising portion, the damping device including a first member operatively connected to a second member by an articulation device. The articulation device may be configured to dampen axial movement of the first member relative to the second member.

Abstract: A method of making a compressible elastomeric spring including at least one compressible elastomeric pad enclosed by a pair of metal plates includes the steps of forming plates with a center aperture and a plurality of prongs positioned about a peripheral edge thereof, forming each end of the pad with an axial projection and abutting groove, aligning the plurality of prongs with each respective projection and respective groove and applying axial force to one end of the spring to frictionally interlock the plurality of prongs with such projection and groove. The method also provides for making a multi-tiered stack of pads separated by plates in the above described manner and pre-shortening the spring prior to installation into the conventional yoke. The above described method additionally improves axial straightness and lateral stability of the multi-tiered spring assembly.

Abstract: A gas spring and damper assembly can include a first gas spring having a first spring rate and a second gas spring connected in series with the first gas spring. The second gas spring can have a second spring rate that is at least two times the first spring rate of the first gas spring. A damper can be operatively connected with at least one of the first and second gas springs. A suspension system including one or more of such gas spring and damper assemblies and a method of assembly are also included.

Abstract: A leaf spring manufactured from composite material has a variable cross sectional area. The leaf spring is manufactured by die forming a core of a constant cross section, then winding fibres onto the core to create a spring with a variable cross section and then cutting the spring to size. A ply lay-up station is shown which winds fibre onto a die formed workpiece as it moves through the station.

Abstract: A vehicle transmission includes a housing part, a shaft extending from the housing part, and a spring element having a plurality of spring windings wound around the shaft, a first end of the spring element being fixed to the housing part. An actuating means is attached to a second end of the spring element and is configured to twist the second end in a circumferential direction of the spring element to thereby cause the spring element to tighten and frictionally contact an outer circumference of the shaft. The spring element is comprised of a hollow cylindrical metal base body having a helical-shaped incision that defines the plurality of spring windings. The incision may be formed in the hollow cylindrical base body by a plasma beam process, by a laser cutting process, by a flame cutting process or by a water jet cutting process.

Abstract: A method of manufacturing suspension devices comprising the steps of: a) forming an integral elastic sheet, the elastic sheet having first and second suspension devices, each suspension device being provided with attachment parts configured to be fixed to a movable object, fixing parts configured to be fixed to a base, and elastic parts connected between the attachment parts and the fixing parts respectively and configured to bias the object relative to the base, the elastic parts of the suspension devices being alternately distributed; b) separating the first and second suspension devices from each other before being attached to the object.

Abstract: A jounce bumper can include a mounting wall and at least one helical thread. An end member can be at least partially formed from a quantity of polymeric material and can include a base wall and at least one helical thread integrally formed from the quantity of polymeric material. The end member and the jounce bumper can form a gas spring assembly. A method of assembly is also included.

Abstract: Compression springs, such as helical compression springs, include end portions with selectively contoured inner contact surfaces. The selective contours of the inner contact surfaces may take the form of planar, grooved, concave, or other shaped, non-circular surfaces. In addition, enough of the inner contact surface is contoured to reduce the contact stress and/or stress concentration effects on the adjacent coils when the compression spring is placed under load and the adjacent coil engages or contacts the respective end portion. The selective contouring of the end portions may be accomplished by holding the spring in a holder and moving a cutter relative to the end portion of the spring to remove the desired amount of material from the end portion.

Abstract: A suspension system for supporting a vehicle body includes an axle and a mounting member that is coupled by a first coupling member to the axle. The mounting member is also coupled by a second coupling member to the axle. At least one of the first and second coupling members includes a mount damper that dampens loads transferred between the mounting member and the axle. The suspension system also includes a track bar that is coupled by a third coupling member to the vehicle body and that is coupled by a fourth coupling member to the mounting member.

Abstract: A device for the elastic mounting of an engine, in particular an engine transmission unit, on a motor vehicle body, comprising a rigid support with a supporting section and a mounting section, to which the engine can be fastened, a rigid flange ring which can be fastened to the motor vehicle body and surrounds the full circumference of the supporting section, and a spring body which is elastically supported on the supporting section of the support and on an inner side of the flange ring.

Abstract: Provided are: a steel wire rod material for a high-strength spring, which does not undergo the increase in deformation resistance arising from the increase in hardness and can exhibit good wire-drawing processability and the like even when a heat treatment, which deteriorates productivity, is eliminated or a simplified and rapid heat treatment is employed instead; a useful method for producing the steel wire rod material for a high-strength spring; a high-strength spring produced using the steel wire rod material for a high-strength spring as a material; and others. This steel wire rod material for a high-strength spring is a steel wire rod material that has been hot-rolled already, and has a texture having a specified chemical composition and mainly composed of pearlite, wherein the average value (Pave) of the pearlite nodule size numbers and the standard deviation (P?) of the pearlite nodule size numbers fulfill the following formulae (1) and (2), respectively: 9.5?Pave?12.0;??(1) and 0.2?P??0.

Abstract: A method of manufacturing a coil spring using a helicoid reduction mill includes supplying a coil spring material linearly unrolled by a prestraightener to a surface treatment machine and then short-blasting or scarfing its outer surface to surface-treat the coil spring material; primarily heating the surface-treated coil spring material to a predetermined temperature using a first heater; sequentially supplying and pressurizing the primarily-heated coil spring material in a stepwise fashion such that the coil spring material has the same diameter as that of a coil spring to be manufactured; measuring the diameter and the length of the coil spring material and then cutting the coil spring material to a desired size; secondarily heating the cut coil spring material to a predetermined temperature using a second heater; forming the secondarily heated coil spring material into a coil spring using a coiling machine; and oil-quenching and then tempering the formed coil spring.

Abstract: A method of producing a modular independent suspension having portal wheel ends is disclosed herein. The method includes, but is not limited to, assembling a first flank component and a second flank component to opposite sides of a sub-frame configured to receive a carrier. The method further includes assembling a first upper control arm and a first lower control arm to the first flank component. The method further includes assembling a second upper control arm and a second lower control arm to the second flank component. The method further includes assembling a first portal wheel end to the first upper control arm and the first lower control arm. The method still further includes assembling a second portal wheel end to the second upper control arm and the second lower control arm.

Abstract: A bicycle shock absorber having a primary unit and a remote unit that can be substantially entirely outside of the primary unit. The primary unit includes a damper tube, a spring chamber, and a piston rod that supports a main piston for movement within the damper chamber of the primary unit. The main piston and the damper tube at least partially define a compression chamber. The remote unit comprises a remote fluid chamber and, in some arrangements, an inertial valve within the remote unit that preferably is responsive to terrain-induced forces and not responsive to rider-induced forces when the shock absorber is assembled to the bicycle. The inertia valve can include at least one protective coating or layer configured to contact the reservoir shaft. A fluid flow control arrangement can utilize compression fluid flow to delay closing of the inertia valve after acceleration forces acting on the inertia valve diminish.

Abstract: In a method of producing a stabilizer for installation in a bearing unit of a motor vehicle, each end portion of a strip-shaped metal element is provided with a closing contour. The metal element is shaped to assume an undulating configuration having a wave portion. After being placed in a tool, a stabilizer bar is pressed against a circumference of the wave portion of the undulating metal element and the wave portion is formed onto the stabilizer bar such that the wave portion has at least one section which is ironed and the ironed section is urged into forced contact with the stabilizer bar. The metal element is then bent to embrace the stabilizer bar, and the end portions of the metal element are connected by engaging the closing contours of the end portions with a defined incline to thereby form a closed limiter ring fixed to the stabilizer bar.

Abstract: A flexible sleeve dimensioned for securement to an associated end member for an associated gas spring assembly includes a flexible wall. An annular reinforcement member is embedded within the flexible wall. A retainment element that includes an element surface is disposed along the flexible wall such that at least the element surface is outwardly exposed. At least one gas spring piston, at least one gas spring assembly and at least one method are also included.

Abstract: A method for enhancing an initial tension by changing a wound direction of a coil spring. A large and precise initial tension is provided to the coil spring. An actuator having an excellent function is prepared by using a shape memory alloy. Each shape of the coil spring at high and low temperatures can be controlled by a flexible shape memory effect.

Abstract: A spring wire with a hardness of 50 to 56 HRC is subjected to first and second shot peening processes within a warm working temperature range of 150 to 350° C. In the first shot peening process, a first shot of a shot size of at least 1.0 mm is used. In the second shot peening process, a second shot smaller in shot size than the first shot is sued. Through these shot peening processes, compressive residual stress is imparted to the spring wire. The spring wire includes a residual stress increase part, residual stress peak part, and residual stress decrease part. In the residual stress decrease part, a part including a compressive residual stress magnitude equivalent to the magnitude of the compressive residual stress at a surface of the spring wire exists at a region at a depth exceeding the permissible pit depth.

Abstract: A production method for coned disk springs includes: preparing a plate member; punching plural annular blanks from the plate member by pressing; and forming the blanks into coned disk springs. In the pressing, plural slits are formed at one of a peripheral portion and an inner peripheral portion of at least one of the blanks, and a smaller outer diameter blank among the blanks is punched from an inner region of a larger outer diameter blank among the blanks.

Abstract: A vehicle suspension mount (20) for connection of a first vehicle body—structure (22) with a second vehicle body structure (24). The mount including a suspension mount damping liquid damper pumper member (42).

Abstract: A method of manufacturing a vehicle suspension component, such as a helical coil spring, includes the step of rotating a first impeller to project ceramic peening media in a first direction toward the vehicle suspension component to peen a surface section of the vehicle suspension component. In one example, the vehicle suspension component is peened with metal peening media before peening with the ceramic peening media.

Abstract: A manufacturing method of a coil spring for an automobile suspension includes forming a material into a coil shape; performing a heat treatment step on the material; performing a warm shot peening step on the material, and performing a hot setting step on the material. By performing the warm shot peening step prior to the hot setting step, a stronger compressive residual stress is imparted in a direction along which a large tensile stress acts during actual use of the coil spring, thereby improving sag resistance and durability of the coil spring. A coil spring is also manufactured according to this method.

Abstract: A wheelchair conversion vehicle and a method of manufacturing a wheelchair conversion vehicle include replacing the OEM trailing arm with a trailing arm substitute and substantially reproducing the movement of the rear wheel OEM spindle along first or second arc paths between an upper limit and a lower limit. The upper limit is a distance above the OEM ride height and the lower limit is a distance below the OEM ride height. The conversion vehicle and method of manufacturing further include installing a wheelchair access system to provide wheelchair access to the wheelchair conversion vehicle.

Abstract: A suspension coil spring, when assembled to a suspension device, in which a spring reaction axis is positioned coincident with or sufficiently close to a load input axis, and the design and manufacture of coil springs are facilitated. Namely, A suspension coil spring (19) in a free state is formed so that a coil axis (AC) is bent in V-shape at bend point (PB) and the distance from the end turn center (CU) of the upper seating surface (38) to an imaginary coil axis (AI) is an upper inclination amount (VU), and the distance from the end turn center (CL) to the imaginary coil axis (AI) is a lower inclination amount (VL). When the suspension coil spring (10) is interposed between spring seats (22, 24) in the suspension device and compress along a strut axis, the spring reaction axis of the suspension coil spring (10) is inclined and offset with respect to the imaginary coil axis (AI) according to the inclination amounts (VU, VL).

Abstract: Suspension systems and methods of assembling suspension systems for weight-bearing structures are presented. The suspension system can have linearly translating load-bearing or load support members that confine displacement of a weight-bearing body or member to a longitudinal axis or displacement axis rather than a lateral axis or not coincident with the longitudinal axis, comprising a rail and bridge assembly. The linear bearing assembly can comprise a rail and a bridge slidably movable along the longitudinal axis of the rail.

Abstract: A method for manufacturing a pot-shaped pressure vessel, in particular an air spring pot for a vehicle, comprises the following steps: providing a pot, which comprises a bottom, which comprises at least one aperture, providing at least one screw, which comprises a head and a shank, inserting the shank of the at least one screw through the aperture from an inside of the pot, so that the shank of the screw protrudes from an outside of the bottom, and firmly joining the screw to the bottom of the pot. In the transitional area from the head to the shank at least one screw comprises a connecting section tapering from the head to the shank and extending all round the circumference. In inserting the shank through the aperture the connecting section is brought to bear against the edge of the aperture, and the connecting section is joined to the edge of the aperture along its bearing contact with the latter.

Abstract: A base of a shock-absorbing front fork for a bicycle includes two straight tubes and a bridge. The bridge has two ends connected integrally with an upper section of each of the straight tubes. The bridge has a chamber therein. Thus, the base of the shock-absorbing front fork has the advantages of high structural strength and long service life.

Abstract: A clutch apparatus is equipped with two clutch structures having a clutch drum therein. A driven plate and a piston are provided in the clutch drum of each clutch structure, and a primary coned disc spring and a secondary coned disc spring, which are ring-shaped, are provided between the driven plate and the piston. A flat portion 12 is formed on an inner peripheral portion of a convex surface of the primary coned disc spring 1, and the flat portion 12 can come into contact with a counter member first when a load is applied. A load in a flat condition due to elastic deformation is adjusted by the flat portion so as to be a desirable value. Blanks 1A and 2A of the primary coned disc spring and the secondary coned disc spring can be obtained from one sheet of material having the same thickness. In this case, the flat portion 12A is formed by press forming on an inner peripheral portion of the blank 1A in view of the shape thereof after bending forming is performed.

Abstract: Embodiments of the present invention provide a suspension assembly including a bolt made from a bolt material; a suspension component made from a suspension material, the suspension component having a suspension opening therethrough, the suspension opening having a geometry for insertion of at least a first portion of the bolt; and a bushing assembly including an elastomeric element and a bushing opening therethrough, the bushing opening having a geometry for insertion of at least a second portion of the bolt; wherein the suspension material has a yield strength that is substantially higher than a yield strength of the bolt material.

Abstract: A suspension coil spring, when assembled to a suspension device, in which a spring reaction axis is positioned coincident with or sufficiently close to a load input axis, and the design and manufacture of coil springs are facilitated. Namely, A suspension coil spring (19) in a free state is formed so that a coil axis (AC) is bent in V-shape at bend point (PB) and the distance from the end turn center (CU) of the upper seating surface (38) to an imaginary coil axis (AI) is an upper inclination amount (Vu), and the distance from the end turn center (CL) to the imaginary coil axis (AI) is a lower inclination amount (VL). When the suspension coil spring (10) is interposed between spring seats (22, 24) in the suspension device and compress along a strut axis, the spring reaction axis of the suspension coil spring (10) is inclined and offset with respect to the imaginary coil axis (AI) according to the inclination amounts (VU, VL).

Abstract: The invention relates to a method of producing a divided tube stabilizer having a swivel motor (2) mutually coupling two tube stabilizer halves (3, 4), a first tube stabilizer half (3) being non-rotatably connected with a first connection part (5) of the swivel motor, and a second stabilizer half (4) being non-rotatably connected with a second connection part (6) of the swivel motor (2). In order to achieve that the tube stabilizer halves can be easily linked in a non-rotatable manner with the connection parts of the swivel motor, the following process steps are suggested: a. The tube ends to be connected with the connection parts (5, 6) of the swivel motor (2) are expanded and upset in one working step by means of a mandrel (20); b. the tube stabilizer halves (3, 4) with the expanded and upset ends are shaped to their final shape by bending; c. the finished bent tube stabilizer halves (3, 4) are subjected to a heat treatment; d.

Abstract: A spring manufacturing apparatus comprises a tool support (30, 40, 50) which supports a tool in a way that the tool can be slid toward the spring forming space. A plurality of the tool supports can be arranged in a radial pattern from the spring forming space on the forming table. The apparatus also comprises a driving force transmission unit (70), attached to the tool support on the forming table, which transmits driving force to the tool support for sliding the tool. The tool support includes first and second tool supports for driving a tool by different driving methods. The first tool support (30) comprises a first driving mechanism (32) that transmits driving force of a common driving axis to the tool. The second tool support (40) comprises a second driving mechanism (41) that transmits driving force of the driving axis to the tool.

Abstract: A one-way drive device is disclosed herein and includes a pocket plate assembly having a disc-shaped pocket plate and a notch plate assembly having a disc-shaped notch plate. The device also includes an axially extending, open-ended cylindrical shell for containing therein the pocket and notch assemblies. This shell includes opposite first and second axial ends and opposing inner and outer circumferential surfaces which extend axially between the end and which together are configured to include splines and first and second sets of tabs. The splines are circumferentially spaced from one another and extend axially across the shell body and they project radially inward and outward such that there innermost surface edges of the splines together define an innermost annular bearing surface.

Abstract: A production method for coned disk springs includes: preparing a plate member; punching plural annular blanks from the plate member by pressing; and forming the blanks into coned disk springs. In the pressing, plural slits are formed at one of a peripheral portion and an inner peripheral portion of at least one of the blanks, and a smaller outer diameter blank among the blanks is punched from an inner region of a larger outer diameter blank among the blanks.

Abstract: A manufacturing method of a spring assembly, assembles an annular plate and a compression coil spring. The method includes forming a protrusion having a tapered portion on the annular plate, and inserting a punch including a first portion having a larger diameter than an inner diameter of a tip end of the tapered portion from the tip end side into the protrusion to expand the tip end of the tapered portion. The expansion of the tip end of the tapered portion involves expanding a base portion of the protrusion, which extends the tapered portion and has a larger inner diameter than that of the tip end of the tapered portion, along a surface of an end turn of the compression coil spring.