Abstract:
A sheet metal rocker arm of the welded and brazed tube and “boat type” rocker arm formed from sheet metal and characterized by having a reinforcing cross member which is integrally formed from a tab created by slitting the tube insert and which yields a unitary structure that introduces substantially greater stiffness to the rocker arm. The tube may be optionally rolled from sheet metal or by using seamless tubing. The method of creating integrally formed reinforcing cross-members by appropriate lancing slits in the sheet metal can be applied to any stamped rocker arm that has a U-channel architecture, e.g., including, for example, rocker arms for pushrod type valve trains as well as roller finger follower type rocker arms. Provision of the integrally formed cross member renders stiffness to the rocker arm that enables an engine to operate at a higher rpm and thereby to produce more horsepower.
Abstract:
A rocker arm (25) adapted to engage a pair of cam lobes (15,17), the rocker arm having first (31) and second (33) sidewall portions, and being formed from a flat sheet metal blank (25B) having a nominal thickness (T). The sidewall portions (31,33) define fold regions (51,53) whereby, after each is folded over upon itself, and the rocker arm is formed to have the sidewall portions generally parallel to each other, the fold regions provide first (41) and second (43) cam contact surfaces, each having a width (W) substantially greater than the nominal thickness of the blank.
Abstract:
In relation to a rocker arm obtained by applying cold forging to a blank made from a metal wire rod, cold forging is applied to a blank obtained by cutting a metal wire rod to a predetermined length to make a second intermediate blank 34b having a pair of side wall sections 2a and a base 39 which connects the two side walls 2a at one of their respective widthwise edges Punching is applied to the base 39 of this second intermediate blank 34b to form a first and a second connection sections. In the case where it is assumed that a roller 35 is arranged at a position corresponding to an arrangement position of the roller 35 of the rocker arm to be obtained, on the inside of the second intermediate blank 34b which is to be subjected to punch processing, the roller 35 and the base 39 do not interfere with each other. As a result, performance improvement of an engine fitted with this rocker arm is obtained.
Abstract:
When forces given in the processes of machining in the cross direction and machining for forming a groove are adjusted and the machining is repeatedly conducted by a plurality of times, the valve engaging portion (10) is machined, and the metal flow (30) formed between the valve guide walls (28, 29) and the connecting wall (8) is prevented from being cut off. Therefore, the rigidity of the valve engaging portion (10) can be ensured, and the quality of the rocker arm (1) can be stabilized.
Abstract:
A rocker arm 1 includes an arm body 4 prepared from a single plate material by means of a press work. The arm body 4 includes a pair of parallel side walls 5 and a connecting wall 6 bridging between the opposite side walls 5 and also having a pivot support hole 7 defined at a location generally intermediate of the length of the arm body 4. A roller support pin for rotatably supporting a roller 10 for driving engagement with a cam is mounted on one ends 1a of the opposite side walls 5, while the opposite end 1b of the connecting wall 6 defines an overlapped structure 13 formed by bending an end overlap piece 12, extending integrally from a side edge of the connecting wall 6, backwardly to overlap the connecting wall 6. This overlapped structure 13 in turn defines an adjustment element 16 having a mounting hole 15 defined therein for adjustably receiving a valve driving member 14. The rocker arm 1 may be designed to be an end pivot type, in which case the adjustment element 16 is provided with a pivot member.
Abstract:
A sheet metal rocker arm manufactured by the steps of punching one metal plate to form a blank having a predetermined contour and through holes, and subjecting this blank to a bending work based on a press work to form a pair of side walls parallel to each other and a connecting portion for connecting the both ends of the side walls in the width direction thereof. This rocker arm is also provided with at least a pair of though holes formed at positions which are aligned with each other on the both side walls and at least one engagement portion provided in a part of the connecting portion. The thickness of at least one engagement portion, is formed to be greater than the thickness of the both side walls.
Abstract:
To provide a rocker arm of a design effective to avoid occurrence of a loosening of the adjustment screw to ensure a proper operation of the internal combustion engine including the control of the opening of the valve body on the engine cylinder head, the rocker arm 1 is of a type capable of being rockingly driven by a cam 2 for selectively opening and closing a valve of an internal combustion engine. The rocker arm 1 includes an arm body 4 prepared from a steel plate by means of a press work to have a generally inverted U-shaped section. The arm body 4 has one end formed with an internally threaded hole 12 into which an adjustment screw 7 is threaded. This adjustment screw has one end defining a pivot piece 7b or a valve drive piece 7Ab. Two nuts 13 and 14 are threadingly mounted in overlapping relation to each other on one end portion of the adjustment screw 7 protruding outwardly from the arm body. Instead of the use of the two nuts 13 and 14, a flanged nut may be employed or a single nut 13 in combination with a washer 17 may be employed.
Abstract:
An adjustable length composite push rod constructed of a composite bar having two specially shaped ends to which metal end fittings bond via mating surfaces provided thereon for evenly distributing mechanical stress from the metal end fittings to the composite bar. The bar is constructed of a plurality of layers of sheets of thermosetting, epoxy impregnated, longitudinally oriented fiber material that form the inner portion of the push bar and a single outside sheet of thermosetting, epoxy impregnated, woven fiber material forms the outside portion of the bar.
Abstract:
The thickness in the width direction of a pair of side wall sections 4 is made as uniform as possible. In use, a load is applied to the pivot 3 from the side of the first and second connecting sections 5, 6 which connect the pair of side wall sections 4. A crimped section 13a is formed on the outer periphery at the opposite end surfaces of the pivot 3b, on the half on the side of the connecting sections 5, 6. Therefore, the outer peripheral surface of the opposite ends of the pivot 3b comes into contact with the inner peripheral surface of the through hole 11 on the load support side. Consequently, the load is sufficiently supported by the contact surface, and even after being used for a long time of period, lost motion is prevented from occurring on the support section at the opposite ends of the pivot 3 with respect to the pair of side wall section 4.
Abstract:
A gap (34) for forming an excess thickness portion is provided between a pair of first dies (26, 27) and a intermediate portion (32) of the second die (24), and an excess thickness portion (35) is formed in bottom portions of the valve guide walls (28, 29) of valve guide walls.