Elephant Chain Block Co., Ltd.

Yasuo Wada

Yoshio Ueno

Munenobu Honda

Haruo Kubota

Yoshio Nishi

Yoshiaki Okamoto

Yoshitaka Inoue

Eikichi Kobayashi

For providing a chain lever hoist that can ensure a stable free rotation operation over a long term with a simple design, improvement is made in the chain lever hoist wherein an engaging pawl is switched to a neutral position, at which the engaging pawl is not allowed to engage with engaging teeth in the forward direction or a reverse direction, by the operation of a selector lever and then a load chain on the non-loaded side is pulled or an operating handle is rotated in the reverse direction to thereby produce the free rotation state just the way it is, the improvement being such that the operating lever is rotatably supported on a brake cover at its opening with a predetermined spaced interval from a first hub. By virtue of this, the first hub is allowed to rotate together with the drive shaft, without contacting with the operating lever, during the free rotation operation, and as such can attain reliable free rotation operation.

Chain lever hoist

A manual chain block having a hand wheel and hand chain on one axial end and a load wheel and load chain on the other axial end. A no-load side chain guide (44) of the load chain guides (43, 44)is provided with an anchoring portion (45) for anchoring a no-load end portion of a load chain (4). An anchoring portion (45) is provided with a load receiving portion (46) for receiving a load acting on the no-load side end portion.

Load chain retainment for a chain block

One of the hand wheel and the brake ratchet wheel is provided with a cover portion extending toward the other thereof and having a circular peripheral surface which covers the lining plate, and the other of the hand wheel and the brake ratchet wheel is provided with a circular opposite peripheral surface opposed to the circular peripheral surface, so that opposite peripheral surfaces of those circular peripheral surfaces can be arranged adjacently to each other or have a scaling member interposed therebetween. Therefore, even when dust and rainwater enter a wheel cover for a hand wheel, these dust and rainwater can be prevented from further entering a mechanical brake.

Manual chain block

In a lever type hoist an operation handle (18) is provided between a stopper (17) provided at the axial end portion of a driving shaft (5) and a driving member (8) screwed on the driving shaft (5) so as to be movable in the axial direction but non-rotatable relatively to the driving shaft (5). A spring (19) for energizing the operation handle (18) toward the driving member (8) is provided to bring inclined surface (31a) of the engaging projection (31) provided on the operation handle (18) into elastic contact with an engaging stepped portion (37) of the driving member (8) during the time when the mechanical brake (13) is being operated, whereby the driving member (8) can be prevented from being reversely rotated while being accompanied by a returning operation of the operation lever (16) by the engaging resistance of a feed click (14) during the time when a hoist and traction operation is being conducted under the no-load condition.

Structure for controlling braking action of a mechanical brake of a

In a hoist and traction machine including a free rotation control apparatus, a free-rotation spring 19, for urging an operating handle 18 toward a driving member 8 and also urging the driving member 8 in the brake releasing direction, is interposed between the driving member 8 and a stopper 17 provided on a driving shaft 5. When the operating handle 18 is pulled out, the driving member 8 is rotated to move away from a driven member 7 by a torsional urging force of the spring 19 and thereby a braking ratchet wheel 11 and braking plates 9, 10 is released. Engagement lugs 31 are then brought into resilient contact with free rotation surfaces 35 via an axial urging force of the spring 19 to maintain controlled free-rotation.

Free-rotation control apparatus of hoist and traction machine

In a manual chain block with a driving shaft a wheel cover 15 is provided with a radial bearing 18 for supporting the driving shaft 7 at one axial end portion. The driving shaft 7 has an actuating mechanism side shaft portion for supporting an actuating mechanism 20 extended so as to be supported by the radial bearing 18, so that shaft deflection can be decreased at the time of actuating operation of the actuating mechanism 20.

A manual hoist and traction machine wherein an outer diameter of a first lining plate constituting a mechanical brake is made smaller than an inner diameter of a driven disc of a handwheel. The outer diameter of a second lining plate and of a driven disc are made smaller than an inner diameter of a cylindrical portion of a braking ratchet wheel, and the first and second lining plates are formed of a lining raw material having improved performance with a compressive strength of 15 (Kgf/mm.sup.2) or more and a maximum strain of 12 (10.sup.-3 mm/mm) or more.

Manual hoist and traction machine

In a manual chain block having a load sheave and an actuating mechanism with a cover 15 thereover there is provided a cover holding member 50 having side surfaces 51, 52 which define lower opening edges of introducing openings 15b, 15c for a hand chain 40 and a cover receiving portion 55 which is located between the introducing openings 15b, 15c to receive the wheel cover 15. The cover holding member 50 is tightened by stay bolts 12 onto a side plate 1 of the hoist together with the wheel cover 15.

A hoist and traction machine having a mechanical brake (13), wherein a not-relative (14)-rotatable operating handle (18) is axially movably an interposed between a stopper (17) provided at an axial end of a driving shaft (5) and a driving member (8) threadedably engaged with the driving shaft (5). Between the operating handle (18) and the stopper (17) there is provided an elastic biasing member (19) for biasing the operating handle (18) toward the driving member (8) The operating handle (18) is provided with engaging projections (31), the driving member (8) is provided with free rotation control surfaces (35) in elastic contact with the engaging projections (31) respectively, and the free rotation control surfaces (35) are formed in gradient surfaces for applying resistance against movement of the driving member (8) in the return direction with respect to free rotation operation by the operating handle (18) so as to enable the free rotation control state to be held up to a desired value, whereby an input range of a pulling force of a chain during the free rotation control is expanded without reducing operability of free rotation operation.

Free rotation control apparatus for a hoist and traction machine

A hoist and traction machine having a load sheave, a driving shaft and a driving member which is screw-threadedly engageable with the driving shaft. An operating handle 16 has an inner plate 16a and a brake cover 13a to cover a mechanical brake. The inner plate and the brake cover both have apertures of about the same size through which passes a portion of the driving member. A sleeve 102 which is separate from the brake cover and the operating lever is received in the apertures and held in place by a flange and a retaining ring so as to facilitate easy assembly.

Hoist including brake cover and operating lever coupling

A hoist and traction machine having a free rotation control device/apparatus for selectively controlling the mechanical brake to be inoperative and for maintaining the inoperative mode of the mechanical brake, so as to control the free rotation of the load sheave. The free rotation control device is designed such that improved free rotation control operation can be provided, and the range of the pulling force for the chain can be enlarged in the controlled free rotation of the load sheave; thus, allowing the chain to be pulled quicker, while requiring little operating skill. Further, free rotation operation is not provided when the load sheave (and thus the driving shaft) is subjected to a large load acting in the direction of hoisting down the load, thus achieving highly improved safety.

Hoist and traction machine with free rotation control

A hoist and traction machine having a mechanical brake, in which an operating handle is non-rotatably and axially movably interposed between a stopper provided at an axial end of a driving shaft and a driving member screwable with the driving shaft. Between the operating handle and the stopper is provided a regulation unit for regulating a relative rotation range of the driving member with respect to the driving shaft so as to enable release of the regulation by moving the handle away from the driving member, so that the driving member is moved away from a driven member by of moving the operating handle from the driving member to be normally rotated in a free-rotation operation mode whereby the braking action of the mechanical brake by a braking ratchet wheel and braking plates is released to control the free rotation of the driving shaft and the elastic biasing member biases it to maintain the state of free rotation control.

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Osaka Sayama, Japan

Yasuo Wada