A damper spring having an excellent fatigue limit is provided. A damper spring according to the present embodiment includes a nitrided layer formed in an outer layer, and a core portion that is further inward than the nitrided layer. The chemical composition of the core portion consists of, in mass%, C: 0.53 to 0.59%, Si: 2.51 to 2.90%, Mn: 0.70 to 0.85%, P: 0.020% or less, 5: 0.020% or less, Cr: 1.40 to 1.70%, Mo: 0.17 to 0.53%, V: 0.23 to 0.33%, Cu: 0.050% or less, Ni: 0.050% or less, Al: 0.0050% or less, Ti: 0.050% or less, N: 0.0070% or less, and Nb: 0 to 0.020%, with the balance being Fe and impurities. In the core portion, a number density of V-based precipitates having a maximum diameter ranging from 2 to 10 nm is 500 to 8000 pieces/μm.sup.2.

A damper spring having an excellent fatigue limit is provided. A damper spring according to the present embodiment includes a nitrided layer formed in an outer layer, and a core portion that is further inward than the nitrided layer. The chemical composition of the core portion consists of, in mass%, C: 0.53 to 0.59%, Si: 2.51 to 2.90%, Mn: 0.70 to 0.85%, P: 0.020% or less, 5: 0.020% or less, Cr: 1.40 to 1.70%, Mo: 0.17 to 0.53%, V: 0.23 to 0.33%, Cu: 0.050% or less, Ni: 0.050% or less, Al: 0.0050% or less, Ti: 0.050% or less, N: 0.0070% or less, and Nb: 0 to 0.020%, with the balance being Fe and impurities. In the core portion, a number density of V-based precipitates having a maximum diameter ranging from 2 to 10 nm is 500 to 8000 pieces/μm.sup.2.

The disclosure provides a buffer bracket, which comprises a base, a moving part, an elastic buffer and a positioning pin. The base is provided with a group of holes, which comprises a plurality of positioning holes arranged in sequence along the first direction. The moving part is movably fitted to the base along the first direction. The elastic buffer is elastically compressed between the base and the moving part. The locating pin is installed on the moving part. When the moving part moves forward in the first direction relative to the base under external force, the positioning pin is restricted to a certain positioning hole. The beneficial effect of the disclosure is that it can absorb impact energy and avoid rebound.

The disclosure provides a buffer bracket, which comprises a base, a moving part, an elastic buffer and a positioning pin. The base is provided with a group of holes, which comprises a plurality of positioning holes arranged in sequence along the first direction. The moving part is movably fitted to the base along the first direction. The elastic buffer is elastically compressed between the base and the moving part. The locating pin is installed on the moving part. When the moving part moves forward in the first direction relative to the base under external force, the positioning pin is restricted to a certain positioning hole. The beneficial effect of the disclosure is that it can absorb impact energy and avoid rebound.

A device for reducing impact forces upon a surface includes a base comprising a first contact portion and a transition portion, a contact member disposed between the base and the surface; and a biasing portion disposed between the first contact portion of the base and the surface. At least a first portion of an impact force upon the surface is transferred from the contact member to the base, and a second portion of the impact force is subsequently returned to the surface, the second portion being less than the first portion.

A device for reducing impact forces upon a surface includes a base comprising a first contact portion and a transition portion, a contact member disposed between the base and the surface; and a biasing portion disposed between the first contact portion of the base and the surface. At least a first portion of an impact force upon the surface is transferred from the contact member to the base, and a second portion of the impact force is subsequently returned to the surface, the second portion being less than the first portion.

Filtering pulleys have a hub adapted to be fixed to a rotating shaft, a ring assembled coaxial and rotationally free on the hub, and an elastic assembly arranged circumferentially with respect to the hub and the ring and interposed between a pair of first elements integral with the hub and between a pair of second elements integral with the ring. The elastic assembly includes an elastic element having a progressive rigidity increasing starting from a predetermined threshold value of the angle of relative rotation between the hub and the ring.

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.

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.

A squeeze mode giant electrorheological fluid damper is disclosed. The squeeze mode giant electrorheological fluid damper comprises a support, a container and a connecting structure, wherein the support comprises a bottom plate, guide shafts and a top plate, the guide shaft is vertically fixed on the bottom plate, and the top plate is slidably arranged on the guide shaft; the container comprises a container body and two spiral spring pieces coaxially arranged in the container body, the container body is fixed on the bottom plate, the bottoms of the two spiral spring pieces are fixed to the bottom of the container, the two spiral spring pieces are not in contact with each other and are spaced by 180°; the top of the connecting structure is fixedly connected with the top plate, and the bottom of the connecting structure is fixedly connected with the tops of the two spiral spring pieces.