Abstract: Provided is a method for strengthening a steel plate member employing a heating and quenching treatment. The method includes a first heating step, a partial cooling step, a second heating step and an entire cooling step, each step conducted in the written order.

Abstract: Provided is a method for strengthening a steel plate member employing a heating and quenching treatment. The method includes a first heating step, a partial cooling step, a second heating step and an entire cooling step, each step conducted in the written order.

Abstract: Providing a bumper absorbing large amount of impact energy with respect to both a light collision and a heavy collision, and preventing the reinforcement beam from bending and protruding backward at a portion where an obstacle collides and from displacing backward in this protruding state. Provided is a bumper for vehicles including a reinforcement beam made of metal and a pair of support members having a hollow cross section, protruding from a vehicle frame, and supporting the reinforcement beam therebetween. A quenched region is provide over a portion including a middle of the reinforcement beam. Unquenched portions are provided on the pair of connecting portions or a pair of adjacent portions inside the pair of connecting portions.

Abstract: A bumper for vehicles having a high productivity and a large energy absorption amount in which the reinforcement beam is prevented from buckling. The bumper includes a reinforcement beam made of steel and support members protruding from a vehicle frame and supporting the reinforcement beam therebetween. The reinforcement beam is provided with a quenched portion provided at least over a portion where an obstacle hits the reinforcement beam. The reinforcement beam is further provided with unquenched portions next to the portion where the obstacle hits the reinforcement beam to sandwich the quenched portion. A mechanical strength of the unquenched portions is smaller than the mechanical strength of the quenched portion.

Abstract: Providing a bumper absorbing large amount of impact energy with respect to both a light collision and a heavy collision, and preventing the reinforcement beam from bending and protruding backward at a portion where an obstacle collides and from displacing backward in this protruding state. Provided is a bumper for vehicles including a reinforcement beam made of metal and a pair of support members having a hollow cross section, protruding from a vehicle frame, and supporting the reinforcement beam therebetween. A quenched region is provide over a portion including a middle of the reinforcement beam. Unquenched portions are provided on the pair of connecting portions or a pair of adjacent portions inside the pair of connecting portions.

Abstract: A shock absorber capable of preventing the collapse or deformation of a vehicle body member when a local load applied to a bumper, without being influenced by the arrangement and construction of the vehicle body member. The shock absorber comprises a multi-diameter stepped tube having different diameter tube portions integrally formed by partially reducing or partially enlarging a straight tube that can be plastically deformed through a stepped portion connecting those tube portions under installation of which a smaller-diameter tube portion connecting to the bumper and of which a larger-diameter tube portion connecting to the side member, a mounting part having a quadrilateral shape with a diagonal length of which is longer than the diameter of the larger-diameter tube portion and positioned at a front end of the side member, and load transmission members fixed between an outer side surface of the larger-diameter tube portion and the mounting part.

Abstract: A shock absorber as being of a bumper supporting member and a shock absorber as being of a side member, which retain the sinking motion of a smaller-diameter tube portion into a larger-diameter tube portion even if an impact is applied at a larger angle obliquely of an axial direction, thereby to achieve the absorption of the impact energy by a plastic deformation. A plastically deformable straight tube is partially reduced or partially enlarged to form a smaller-diameter tube portion and a larger-diameter tube portion, which join to each other through a step portion. The step portion is formed by joining a folded-back portion of the smaller-diameter tube portion and a folded-back portion of the larger-diameter tube portion, which have circular arc-shaped sections having arcuate angles more than 90 degrees.

Abstract: A method for producing a bumper reinforcement having a hollow and a substantially rectangular cross sectional shape formed by the steps of providing a straight tubular member and forming a curved bumper reinforcement, continuously; wherein angle portions of the straight tubular member having the radius of curvature established in profiling corner portions of an inner die having the radius established in larger than the radius of the corner portions of the outer die are bulged in a range of relief spaces formed between the corresponding corner portions of the inner die and the outer die to prevent generation of the wrinkles particularly on the angle portions of the straight tubular member while being curved.

Abstract: A bumper reinforcement comprises an outer reinforcement and an inner reinforcement wherein the outer reinforcement of an open section is formed by a front face, an upper face, and a lower face; and the inner reinforcement housed in the outer reinforcement is formed symmetrically from the center in vertical direction by a intermediate portion formed by edge portions of inner skirt plate portions confronting each other, the inner skirt plate portion, a top portion, an outer skirt plate portion, and an outer contact face portion. The outer reinforcement comprises a concave groove portion in the front face, and a pair of ribs in the upper/lower face. Accordingly, the bumper reinforcement of the invention has achieved high rigidity against the impact applied and easy manufacturing with high cost performance and capability of various designing of the vehicles.

Abstract: A shock absorber comprising a first collapsible shock absorbing part and a second shock absorbing part adapted to be compressed in an axial direction thereof inclined outward in the width direction of a vehicle. The first shock absorbing part has a structure of a basin-like truncated conical shape having a bead integrally formed therewith. The direction of the transmission of an impact force F is corrected by utilizing this first shock absorbing part to an axial direction of the second shock absorbing part, and the second shock absorbing part is thereby compressed in the axial direction without inclining the second shock absorbing part.

Abstract: A shock absorber comprising a first collapsible shock absorbing part and a second shock absorbing part adapted to be compressed in an axial direction thereof inclined outward in the width direction of a vehicle. The first shock absorbing part has a structure of a basin-like truncated conical shape having a bead integrally formed therewith. The direction of the transmission of an impact force F is corrected by utilizing this first shock absorbing part to an axial direction of the second shock absorbing part, and the second shock absorbing part is thereby compressed in the axial direction without inclining the second shock absorbing part.

Abstract: A shock absorber capable of preventing the collapse or deformation of a vehicle body member when a local load applied to a bumper, without being influenced by the arrangement and construction of the vehicle body member. The shock absorber comprises a multi-diameter stepped tube having different diameter tube portions integrally formed by partially reducing or partially enlarging a straight tube that can be plastically deformed through a stepped portion connecting those tube portions under installation of which a smaller-diameter tube portion connecting to the bumper and of which a larger-diameter tube portion connecting to the side member, a mounting part having a quadrilateral shape with a diagonal length of which is longer than the diameter of the larger-diameter tube portion and positioned at a front end of the side member, and load transmission members fixed between an outer side surface of the larger-diameter tube portion and the mounting part.

Abstract: A bumper reinforcement attached to a front or a rear side of a vehicle frame as a strength member comprising: a bumper beam to be supported on the vehicle frame, and a reinforcement member attached to the bumper beam on a forward surface thereof which is upstream with respect to an impact exertion direction, wherein: the reinforcement member has a concave portion of a substantially C-shaped cross section projecting in a downstream direction reverse to the impact exertion direction, the bumper beam has a groove portion extending longitudinally of the reinforcement member on the forward surface to which the reinforcement member is attached, and the reinforcement member and the bumper beam are engaged by joining a bottom surface of the concave portion and a surface of the groove portion.

Abstract: A method for producing a bumper reinforcement having a hollow and a substantially rectangular cross sectional shape formed by the steps of providing a straight tubular member and forming a curved bumper reinforcement, continuously; wherein angle portions of the straight tubular member having the radius of curvature established in profiling corner portions of an inner die having the radius established in larger than the radius of the corner portions of the outer die are bulged in a range of relief spaces formed between the corresponding corner portions of the inner die and the outer die to prevent generation of the wrinkles particularly on the angle portions of the straight tubular member while being curved.

Abstract: A bumper reinforcement comprises an outer reinforcement and an inner reinforcement wherein the outer reinforcement of an open section is formed by a front face, an upper face, and a lower face; and the inner reinforcement housed in the outer reinforcement is formed symmetrically from the center in vertical direction by a intermediate portion formed by edge portions of inner skirt plate portions confronting each other, the inner skirt plate portion, a top portion, an outer skirt plate portion, and an outer contact face portion. The outer reinforcement comprises a concave groove portion in the front face, and a pair of ribs in the upper/lower face. Accordingly, the bumper reinforcement of the invention has achieved high rigidity against the impact applied and easy manufacturing with high cost performance and capability of various designing of the vehicles.

Abstract: A shock absorber as being of a bumper supporting member and a shock absorber as being of a side member, which retain the sinking motion of a smaller-diameter tube portion into a larger-diameter tube portion even if an impact is applied at a larger angle obliquely of an axial direction, thereby to achieve the absorption of the impact energy by a plastic deformation. A plastically deformable straight tube is partially reduced or partially enlarged to form smaller-diameter tube portion and larger-diameter tube portion, which joins to each other through a step portion. The step portion is formed by joining a folded-back portion of the smaller-diameter tube portion and a folded-back portion of the larger-diameter tube portion, which have circular arc-shaped sections having arcuate angles more than 90 degrees.

Abstract: A bumper reinforcement attached to a front or a rear side of a vehicle frame as a strength member comprising: a bumper beam to be supported on the vehicle frame, and a reinforcement member attached to the bumper beam on a forward surface thereof which is upstream with respect to an impact exertion direction, wherein: the reinforcement member has a concave portion of a substantially C-shaped cross section projecting in a downstream direction reverse to the impact exertion direction, the bumper beam has a groove portion extending longitudinally of the reinforcement member on the forward surface to which the reinforcement member is attached, and the reinforcement member and the bumper beam are engaged by joining a bottom surface of the concave portion and a surface of the groove portion.

Abstract: A vehicle bumper assembly characterized by high connection strength with reliable impact absorption, wherein a support bracket is in the form of multi-step structure, a small tube portion of one end of the support bracket is provided with a bumper connection member connected to a bumper and a large tube portion of the other end of the support bracket is provided with a vehicle body connection member attachable to and detachable from a vehicle body member, the bumper connection member is installed to one end or one end portion of the bumper, a connection hole is provided on the bumper connection member for inserting the small tube portion, and the bumper and the support bracket is connected by inserting the small tube portion into the connection hole and by welding the side surface of the small tube portion at a cylindrical wall of the peripheral edge of the connection hole.

Abstract: A vehicle bumper assembly characterized by high connection strength with reliable impact absorption, wherein a support bracket is in the form of multi-step structure, a small tube portion of one end of the support bracket is provided with a bumper connection member connected to a bumper and a large tube portion of the other end of the support bracket is provided with a vehicle body connection member attachable to and detachable from a vehicle body member, the bumper connection member is installed to one end or one end portion of the bumper, a connection hole is provided on the bumper connection member for inserting the small tube portion, and the bumper and the support bracket is connected by inserting the small tube portion into the connection hole and by welding the side surface of the small tube portion at a cylindrical wall of the peripheral edge of the connection hole.