Jtekt Corporation

Koyo Seiko Company, Ltd.

Akihide Nagayama

Nobuo Komeyama

Takeshi Miyachi

Kazushige Ootsuka

Youichi Numada

Nobuo Nakagawa

A torque limiter includes a shaft member, and a cylindrical member which is fitted rotatably on the shaft member. When the cylindrical member is rotated relative to the shaft member in such a state that the cap member is not screwed in the threaded hole and in such a state that the oil release passage is not opened to the outside, the other end portion of the oil release passage circumferentially moves within the circumferentially extended groove while being spaced apart from the circumferentially extended groove.

Torque limiter

A torque limiter in which an area of a region where an area of a region where an inner face of a circumferentially extending chamber intersects an oil pressure expanding chamber in an extended plane extended toward the oil pressure expanding chamber is larger than a sectional area of an opening of the oil removing hole which is opened to the circumferentially extending chamber.

A shear valve protection member is disposed radially outwards of the shear valves and in the same axial position as the shear valves, which can be switched between a tightly attached state in which the strip-shaped shear valve protection member cannot move relatively to a cutting portion which connects to the other member by virtue of a frictional force generated between the cutting portion and itself by tightly attaching the cutting portion thereto in the radial direction and a tight attachment cancelled state in which the strip-shaped shear valve protection member can move in a circumferential direction relative to the cutting portion. The shear valve protection member can be switched between a position where the shear valves are covered with the shear valve protection member and a position where the shear valves are exposed from the shear valve protection member through the through holes therein.

A torque limiter in which an area of a region where an inner face of a circumferentially extending chamber intersects an oil pressure expanding chamber in an extended plane extended toward the oil pressure expanding chamber is larger than a sectional area of an opening of an oil removing hole which is opened to the circumferentially extending chamber.

A torque limiter includes a cylindrical member, and a shaft member which is fitted rotatably in the cylindrical member. The cylindrical member has a main body portion having in an interior thereof an oil pressure expansion chamber for pressing an inner circumferential surface of the cylindrical member against an outer circumferential surface of the shaft member and an oil release passage which is opened to the oil pressure expansion chamber at one end portion while being closed tightly at the other end portion and which is positioned further radially outwards than an outer circumferential surface of the main body portion. When the cylindrical member stays still relative to the shaft member, the other end portion of the oil release passage is accommodated within a cap member which is screwed to be fixed in a threaded hole. When the cylindrical member rotates relative to the shaft member, the other end portion of the oil release passage is broken by the cap member, whereby the oil release passage is opened to the outside. When the cylindrical member is rotated relative to the shaft member in such a state that the cap member is not screwed in the threaded hole and in such a state that the oil release passage is not opened to the outside, the other end portion of the oil release passage moves in the circumferential direction within circumferentially extended groove while being spaced apart from the circumferentially extended groove.

A torque limiter includes a shaft member, a cylinder member, and a traction oil. The shaft memberhas an outer circumferential surface, and the cylinder memberhas an inner circumferential surfacewhich is to be frictionally coupled to the outer circumferential surfaceof the shaft memberduring torque transmission. The traction oil is interposed between the outer circumferential surfaceof the shaft memberand the inner circumferential surfaceof the cylinder member

A torque limiter includes a shaft memberand a cylinder member. An oil-seal preventing grooveopened on axial both sides of the shaft memberis formed in an outer circumferential surfaceof the shaft memberto be frictionally coupled to an inner circumferential surfaceof the cylinder memberin torque transmission.

There is provided a universal joint which is a universal joint of a block type in which a bearing cup for supporting a trunnion of a joint cross is integrally formed with a key portion, and the bearing cup is joined to be fixed to a yoke by a bolt in a state of fitting the key portion to a key way of the yoke, in which by forming WC&#x2014;Ni&#x2014;Cr thermally-sprayed coatings at both side surfaces of the key portion, corrosion resistance of the key portion is promoted, even when used over a long period of time in a drive system of a rolling mill or the like, a clearance between the key portion and the key way caused by corrosion of the key portion is prevented from being brought about, and a stable performance can be maintained over a long period of time by promoting service life of the bearing and preventing an excessively large bending load from being operated to the bolt.

Universal joint

In a torque releasing device, a bearing is composed of an angular contact ball bearing, raceway surfaces of which are applied with a pre-load in order that the occurrence of fretting at the bearing during torque transmission may be prevented. Thus is ensured that the torque is securely released.

Growing community of inventors

Kashiba, Japan

Akihide Nagayama