Hitachi Construction Machinery Co., Ltd.

Other

Hitachi Chemical Company, Ltd.

Hitachi Powdered Metals Co., Ltd.

Nippon Valqua Industries, Ltd.

Osamu Gokita

Hideki Akita

Shigeyuki Sakurai

Ryohei Suzuki

Hiroshi Nishimura

Hideaki Kawata

Motohiro Miyasaka

Hidekazu Tokushima

Daisuke Fukae

Makoto Sugaya

Osamu Mawatari

Kazuo Maruyama

Michiharu Mogami

Wataru Idetsu

Hiromasa Muraki

Junichi Kobayashi

Tatsuo Takamure

Noriyuki Ando

Hajime Maezawa

Hideyuki Fujiya

Nobuo Yanaka

Minoru Fujisaki

Tomiyoshi Yamazaki

Eiji Negoro

Akiko Sato

Yasuchika Nagai

Akiko Satou

A sliding bearing assembly for joints of construction equipment can be provided, in which production cost is reduced by decreasing the used amount of Cu and sulfides having high fixability to a matrix are dispersed. The sliding bearing assembly for joints of construction equipment, includes at least a shaft and a bush made of an iron-based sintered material which functions as a sliding bearing, in which the bush has the overall composition of, by mass %, 0.1 to 10% of Cu, 0.2 to 1.2% of C, 0.03 to 0.9% of Mn, 0.36 to 1.68% of S, and the balance of Fe and inevitable impurities, a metal structure has pores dispersed in a matrix mainly including a martensite structure and sulfide particles precipitated and dispersed, and the sulfide particles are dispersed at 1 to 7 volume % in the matrix.

Sliding bearing assembly

Provided are a novel sliding bearing and a construction machine provided with same, the sliding bearing being capable of maintaining an excellent sliding performance over a long period of time and exhibiting an excellent strength. A sliding bearing includes at least a brush and a shaft part, the shaft part being provided with a grease feeding pathway for feeding grease from the exterior to the sliding surfaces of the shaft part and the bush, the bush being formed from a porous sintered metal, and a decomposition catalyst being adhered to the sliding surface of the bush.

Sliding bearing and construction machine provided with same

A dust seal is provided with a tubular fitting portion, a bush end surface abutting portion, a lip portion and a sealing projection integrally formed. The sealing projection is formed to project in an axially opposite direction to the lip portion from a radial inner section of the bush end surface abutting portion and abuts against a chamfered portion of a bush in such a manner as to overlap the chamfered portion. Therefore, at the time of supplying lubricant between the bush and a connecting pin, the sealing projection can prevent a part of the lubricant from entering between an end surface of the bush and the bush end surface abutting portion of the dust seal to maintain a sealed state therebetween. In consequence, the dust seal can be stably held on the inner peripheral side of a boss member, preventing the pulling-out of the dust seal.

Bearing device

A two-member connection structure is provided with a boom to be arranged on a hydraulic excavator, an arm arranged inboard the boom, outboard bushings and inboard bushings press-fit in pin holes of the boom and arm, respectively. A connector pin is inserted in holes of the outboard bushings and holes of the inboard bushings to connect the boom and arm as two members for relative pivotal movement. Flange portions are integrally arranged on opposite end portions of the connector pin, respectively, to restrict slip-out of the connector pin. The connector pin is arranged rotatably relative to both of the outboard bushings and the inboard bushings, and the flange portions are arranged slidably relative to outboard end faces of the corresponding outboard bushings without being prevented from rotation relative to the boom.

Two-member connection structure for working machine

Grease for a slide bearing, which can suppress unusual noise attributable to a slip caused between a shaft and a bearing when a machine is stopped. In slide bearing greasesupplied to between a slide bearingformed of a porous sintered alloy-made bushing having poresimpregnated with lubricating oiland a shaftinserted in the slide bearingand supported to be slidingly rotatable in the circumferential direction, the slide bearing greaseemploys base oil having dynamic viscosity of 10-70 mm/s at 40&#xb0; C. and exuding under a load of the shaftto form an oil filmbetween the slide bearingand the shaft

Grease for slide bearing

A parallel support member is constituted by a pair of links that are respectively arranged on the left and right sides of a second boom. These links are connected between a first boom and a third boom. Thus, the second boom is moved to the left or right side by an offset cylinder. In this case, when one of the links pulls the third boom, the third boom, an arm, and a bucket can be moved toward the left or right side of a vehicle body to be parallel to the first boom. At this time, the links accept a force exerted in the pulling direction, but need not receive a force exerted in the compression direction, so that the cross sectional areas, the weights of these links can be reduced.

Working mechanism for construction machine

Protective projections (D) which are provided on cylinder mounting brackets () of a cargo handling tool () are arranged to project toward a vehicle body () from behind the cargo handling tool (). When the vehicle body () is driven in reverse direction with a boom () in a folded position on the side of the ground, the protective projections (D) are collided against obstacles (A) on the ground prior to a rod (C) of a fork cylinder () if the lower side (A) of the vehicle body () has passed over and clear of the obstacles (A). Thus, the protective projections (D) function to protect the fork cylinder rod (C) of the fork cylinder () against direct collision against obstacles (A) on the ground.

Self-propelled working machine

An oil-impregnated sintered sliding bearing formed of a porous iron-based sintered alloy with quenched structure and receiving a high surface pressure capable of reducing the number of finishing steps by cutting and grinding and providing a bearing performance equivalent to or higher than that of conventional bearings, wherein a plurality of ridge-and-groove lines having a height difference of 2 to 12.5 &#x3bc;m and extending in circumferential direction are axially arranged in parallel with each other by boring the bearing surface thereof to form a wavy surface in axial direction, and the portion thereof deeper by 10 to 60 &#x3bc;m from the outer layer of the bearing surface is formed dense to seal surface pores so as to reduce the pores opening to the outer surface to 1 to 10 percent by area, whereby the bearing can be used at a surface pressure of 6 kgf/mm(58.5 MPa) or higher and a sliding speed of 2 to 5 cm/s.

Oil-impregnated sintered sliding bearing

A seal device ( ) for a bearing system ( ) is constituted by first and second seal rings ( ) and ( ). The first seal ring ( ) is constituted by a lip seal ( ) having a lip portion ( B) in sliding contact with an end face ( B) of a bush ( ) which is fitted on a joint shaft ( ), and a slide tube ( ) having a seal surface ( C) on an end face at an axial end away from the lip portion ( B) which is formed integrally with a tubular body portion ( A) of the lip seal ( ). The second seal ring ( ) is fixedly fitted in a boss ( ) radially on the outer side of the first seal ring ( ), and provided with a seal surface ( D) on the inner side of an annular inward collar portion ( C) for sliding contact with the seal surface ( C) of the slide tube ( ).

Sealing device

Prior to forming a thermal spray coating layer ( ) on an end face ( B&prime;) of a structural base material ( &prime;) to be shaped into a boss, firstly an inner masking member ( ) is fitted in an original hole ( A&prime;) of the structural base material ( &prime;) and then an outer masking member ( ) is fitted on outer peripheral side of the structural base material ( &prime;). In the next place, by the use of a hard material, a thermal spray coating layer ( ) is formed on an annular coating area ( B &prime;) which is exposed between the inner and outer masking members ( ) and ( ). Surface areas on the end face ( B&prime;) of the structural base material ( &prime;), corresponding to an allowance range of a machining operation by which the original hole ( A&prime;) is ultimately shaped into a joint pin hole of a specified diameter, are left as a non-coating area ( B &prime;) free of the thermal spray coating layer ( ). Therefore, the original hole ( A&prime;) in the structural base material ( &prime;) can be machined into a final joint pin hole by means of a cutting tool, without experiencing cracking troubles which would otherwise occur to the thermal spray coating layer ( ) during the machining operation.

Method of producing spray deposit on bearing boss

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Tsukuba, Japan

Osamu Gokita