Abstract: A pressing apparatus includes a lower die (24) fixed to a lower plate (11), and first and second plate (11), and first and second upper die punches (33 and 34) capable of being lifted and lowered along with an upper plate (12). The first upper die punch (33) supported by a spring (49) is capable of being lifted and lowered relative to the second upper die punch (34). The upper plate (12) is lifted and lowered, while intermittently feeding a band-shaped work (W) one pitch by one pitch from the right to the left along an upper surface of the lower die (24), thereby pressing the work (W) to form grooves in the work (W) continuously. When the groove is formed in the work (W) by pressing the work (W) by the second upper die punch (34), the groove formed at the last time by pressing the work (W) by the second upper die punch (34) is retained and positioned between the first upper die punch (33) and the lower die (24).

Abstract: A condenser includes a cooling section having a plurality of vapor passages to convert vapor into water, a blower for drawing water produced in the vapor passages out of the vapor passages, and a recovery section for receiving the drawn-out water. Thus, the water produced in the vapor passages in the cooling section can be prevented from occluding the vapor passages.

Abstract: In an internal combustion engine, a combustion chamber is provided in a cylinder head on one side of a partition wall, and a heat-insulating layer is provided in the cylinder head on the other side of the partition wall. Cooling passages are provided in a plurality of regions provided with different heat loads in the partition wall, respectively. The flow rate of a cooling medium is set, so that the flow rate in the cooling passage existing in the region of the larger heat load is larger than that in the cooling passage existing in the region of the smaller heat load. Thus, the temperature of an exhaust gas can be maintained at a high level by maintaining the combustion chamber at a high temperature.

Abstract: A pressing apparatus includes a lower die (24) fixed to a lower plate (11), and first and second plate (11), and first and second upper die punches (33 and 34) capable of being lifted and lowered along with an upper plate (12). The first upper die punch (33) supported by a spring (49) is capable of being lifted and lowered relative to the second upper die punch (34). The upper plate (12) is lifted and lowered, while intermittently feeding a band-shaped work (W) one pitch by one pitch from the right to the left along an upper surface of the lower die (24), thereby pressing the work (W) to form grooves in the work (W) continuously. When the groove is formed in the work (W) by pressing the work (W) by the second upper die punch (34), the groove formed at the last time by pressing the work (W) by the second upper die punch (34) is retained and positioned between the first upper die punch (33) and the lower die (24).

Abstract: In an exhaust port structure in an internal combustion engine, a cylinder head has a cylinder head body and a cylindrical exhaust port liner. The exhaust port liner is partially supported at a plurality of points on the cylinder head body, and a heat-insulating layer exists around the exhaust port liner. Thus, it is possible to inhibit the propagation of heat from the exhaust port liner to the cylinder head body as much as possible.

Abstract: A condenser includes a cooling section having a plurality of vapor passages to convert vapor into water, a blower for drawing water produced in the vapor passages out of the vapor passages, and a recovery section for receiving the drawn-out water. Thus, the water produced in the vapor passages in the cooling section can be prevented from occluding the vapor passages.

Abstract: A hollow shaft is manufactured by defining a through hole axially in a shaft blank to produce a cylindrical hollow shaft blank, inserting a mandrel in the through hole of the hollow shaft blank, holding opposite ends of the mandrel concentrically with the through hole, and rotating the hollow shaft blank about its own axis while cutting an outer circumferential surface of at least one end of the hollow shaft blank concentrically with the through hole to form a reference outer circumferential surface on the at least one end of the hollow shaft blank. After the reference outer circumferential surface is formed, it is held in position, and the hollow shaft blank is rotated about its own axis while cutting a predetermined thickness of an outer circumferential surface of the hollow shaft blank over a substantially entire length thereof for thereby finishing the hollow shaft blank into a hollow shaft.