According to an embodiment, a coil spring includes a wire rod having an end and the other end. The wire rod of the coil spring includes, with regard to a section of the wire rod, a round section portion of an effective spring part, a square section portion in which the section is substantially square, and a taper portion. The square section portion includes an end turn part. A length of each side of the section of the square section portion is less than or equal to a square root of ½ multiplied by a diameter of the wire rod of the round section portion. In the taper portion, from the round section portion to the square section portion, the section changes from a round shape to substantially a square shape, and a sectional area is decreased.

A bumper spring assembly having a one piece mandrel including an integral head piece is further configured with a cage assembly retained on the mandrel with a cage nut locked to the mandrel to obviate the need for pins, set screws, and the like, to provide a more robust assembly. In two embodiments the cage nut is locked to the mandrel in a swaging operation. Improved flow of fluids through and around the bumper spring assembly are also provided

The disclosure provides a vibration isolation structure for linear oscillating motor and Stirling engine, wherein the said vibration isolation structure comprises a first vibration isolation device and a second vibration isolation device. The first vibration isolation device is set between the fixed hood and the housing of the linear oscillating motor to attenuate the high-frequency and small-amplitude vibrations from the linear oscillating motor. The first vibration isolation device comprises a first set of tension springs and a second set of tension springs, and a lateral gap is formed between the fixed hood and the linear oscillating motor. The second vibration isolation device is set in the said lateral gap to attenuate the low-frequency and large-amplitude vibrations from the linear oscillating motor. The second vibration isolation device comprises at least two sets of position-limiting protrusions and position-limiting blocks, and the position-limiting protrusion and position-limiting block are set in a match at the linear oscillating motor and the fixed hood respectively or reversely. Also disclosed is a Stirling engine assembled with a linear oscillating motor that comprising with an aforementioned vibration isolation structure. The vibration isolation structure improves the stability of the reciprocating linear oscillating motor and the Stirling engine, and reduces mechanical vibrations and noises.

A spring apparatus (10), including: a spring (12); an elongated object (18A) disposed within and along the spring (12); and a mode-changing assembly (16), for providing a first mode in which a portion (38) of the spring (12) being along the elongated object (18A) is not springy, and a second mode in which an entire of the spring (12) is springy.

In the coil spring of the present invention, a helical space defined by a space between coils has a first end region whose space is increased as it extends towards the other side in the axial direction from a first reference point where the space is zero, a reference region whose space is set at a reference value L (L>0), and a second end region whose space becomes narrow as it extends toward the other side in the axial direction and zero at a second reference point. The first end region is configured such that the number of turns of the helical space is greater than 1 and the space between coils in a terminal position is greater than the reference value L. The helical space has a first transitional region between the terminal position of the first end region and the reference region, the first transitional region being configured so that the distance of space between coils is reduced from the terminal position of the first end region along the helical shape of the helical space toward the other side in the axial direction and becomes the reference value L.

A shock absorber includes a hollow rod, a suspension spring arranged outside the hollow rod, a spring receiver arranged to be displaceable with respect to the hollow rod and receiving a load of the suspension spring, an adjusting screw inserted into one end side of the hollow rod and configured to adjust a position of the suspension spring by restricting movement of the spring receiver to the one end side, and a shaft member which transmits a load received by the spring receiver to the adjusting screw inside the hollow rod. An insertion portion which extends in an axial direction of the hollow rod and into which the shaft member is inserted is provided on a side surface of the hollow rod.

A steel wire for a spring includes a steel wire that has Ca or Na adhered thereto in an amount of 0.2 g/m.sup.2 or less. The steel wire has an oxide film on a surface thereof, and the oxide film has a thickness of, for example, from 2.0 μm to 20 μm.

The present invention discloses a three-dimensional seismic and vibration isolator with adaptive stiffness property in both vertical and horizontal directions. The isolator comprises an upper connection plate, a middle plate, an under connection plate, a disc spring, pre-compressed helical springs, a laminated lead rubber bearing, and viscous dampers. The upper connection plate, middle connection plate and under connection plate are made of high strength low carbon steel with high loading capacity. The upper connection plate and middle plate are tightly contacted by the occlusive design, to guide the vertical motion. The vertical isolation system is made up of the disc spring, pre-compressed helical spring, and viscous damper. The horizontal isolation system comprises the laminated rubber bearing, pre-compressed helical spring and viscous damper. The invention adopts the theory of nonlinear adaptive vibration control technology and can be used to protect building structures or instruments from the seismic strikes or other environmental vibrations.

A vehicle output shaft includes a torque transmission shaft, a drive-side end which is connected to a differential by way of a differential-side joint, and an output-side end which is connected to a driven wheel of the motor vehicle by way of a wheel-side joint, as well as at least one torsional vibration damper. The torsional vibration damper is arranged in a series circuit between the torque transmission shaft and at least one of the joints.

A suspension system for a vehicle and method for operating the same includes a shock absorber housing having a longitudinal axis, a spring disposed around the shock absorber housing, a retainer collar disposed around the shock absorber housing and an actuator engaged to the retainer collar. The actuator moves at least a portion of the retainer collar to move the spring in a direction corresponding the longitudinal axis. A switch generates a ride height position signal. A controller is coupled to the actuator and the switch. The controller controls a position of the actuator in response to the ride height position signal.