Abstract: The invention provides a clutch seal which can enhance a durability of a membrane portion which is a constituting part of a seal and is constructed by a rubber-like elastic body, and can inhibit a working fluid from standing in a concave surface of the membrane portion. The clutch seal of the invention is an annular seal interposed between a clutch plate in a dry clutch and a piston pressing the clutch plate, has a middle ring fixed to the piston between an outer ring and an inner ring which are fixed to a clutch housing, and has membrane portions constructed by a rubber-like elastic body respectively between the outer ring and the middle ring and between the inner ring and the middle ring, wherein the middle ring is arranged at an intermediate position of a stroke in an initial shape of the membrane portion.

Abstract: The invention provides a clutch seal which can enhance a durability of a membrane portion which is a constituting part of a seal and is constructed by a rubber-like elastic body, and can inhibit a working fluid from standing in a concave surface of the membrane portion. The clutch seal of the invention is an annular seal interposed between a clutch plate in a dry clutch and a piston pressing the clutch plate, has a middle ring fixed to the piston between an outer ring and an inner ring which are fixed to a clutch housing, and has membrane portions constructed by a rubber-like elastic body respectively between the outer ring and the middle ring and between the inner ring and the middle ring, wherein the middle ring is arranged at an intermediate position of a stroke in an initial shape of the membrane portion.

Abstract: A shaft part is coaxially provided within a pressure release port provided in a sealing plate sealed to an opening portion of a case for a condenser or a battery, a valve body closely fitted and fixed within the pressure release port has a seal lip which is directed toward the outside of a pressure container and is closely contacted with an outer peripheral surface of the shaft part with predetermined tensional force, and in the case that internal pressure of the case is increased more than a predetermined value, the seal lip is operated so as to open the valve, thereby releasing the internal pressure to the atmospheric air.

Abstract: A shaft part (20) is coaxially provided within a pressure release port (10) provided in a sealing plate (3) sealed to an opening portion of a case for a condenser or a battery, a valve body (30) closely fitted and fixed within the pressure release port (10) has a seal lip (33) which is directed toward the outside of a pressure container and is closely contacted with an outer peripheral surface of the shaft part (20) with predetermined tensional force, and in the case that internal pressure of the case is increased more than a predetermined value, the seal lip (33) is operated so as to open the valve, thereby releasing the internal pressure to the atmospheric air.

Abstract: In a boot for a universal joint in which a fitting portion is installed at one end side in an axial direction of a bellows portion on an outer ring portion of the universal joint by the clamp and a relief portion is provided between the bellows portion and the fitting portion on purpose to lower interference between each of the bellows and to relieve a contact of the bellows portion against the shaft in the case when being bent at a sharp angle. This prevents the relief portion from interfering with the tightly clamping portion of the clamp. The relief portion is designed to be arranged apart from the clamp by providing the spacer portion with the predetermined length in the axial direction between the fitting portion and the relief portion.