The hand wheel cover (3), the speed reducing gear cover (4), the load chain (5), the hand chain (6) and the upper hook (7a) are other key elements.
Numeral 8 designates the load sheave, numeral 9 designates the drive shaft axially supported rotatably by the load sheave (8), while 10a designates the speed reducing gear brought in mesh with the gear (9a) provided at a front end of the drive shaft for reducing a speed of rotation.
Numeral 11 designates the load gear brought in mesh with the small gear (10b) integral with the speed reducing gear (10a) for rotating the load sheave (8). The pressure receiving member (12), the claw (13), the ratchet (14), the brake plate (15), the drive member (17), and a mechanical brake (constituted by the pressure receiving member, 12), are also shown.
The hand wheel (16) and an inner side of an inner periphery of the hand wheel includes a fitting recess portion fitted with the rotation drive member (18).
The ring-like guide portions (16b, 16c) are brought into sliding contact with a guide portion of the drive member (17) and a guide portion of the spring holder (20).
The drive member includes a female thread portion, and is screwed with the female thread portion (12a) of the pressure receiving member. Further, a flange portion of the drive member is provided with an outer diameter larger than the inner diameter of the hand wheel (16), and an end face thereof is constituted by a shape of a circular disk.
An end face of the flange portion of the drive member on a side of the hand wheel is formed with locking teeth. An outer peripheral face of the flange of the drive member (17) is brought into sliding contact with the guide portion (16b) formed at an inner periphery of the hand wheel (16) to support the hand wheel.
Numeral 18 designates the rotation drive member fitted to a boss portion of the drive member. A ring-like link portion and an outer periphery of the ring-like link portion are provided with fitting projected portions extended in an axial direction of the drive member to be fitted to the hand wheel.
A side of the drive member thereof is provided with locking teeth for preventing overload projected from an end face of the rotation drive member (18) on the side of the drive member and brought in mesh with engaging teeth of the drive member (17).
Numeral 19 designates the spring for urging the rotation drive member (18) to the side of the drive member (17).
The spring (19) comprises an inner spring (19a); the outer spring (19b) is wound around the boss portion of the drive member and arranged at a space between the drive member and the inner side of the hand wheel and between the rotation drive member (18) and the spring holder (20).
Bearing plates
Notations 21a and 21b designate the bearing plates fixedly provided to inner peripheral side faces of the connecting frame (2c) for partitioning a space containing the drive means, the speed reducing means and the load sheave, which are provided with fitting recess portions for fitting the bearing plates at inner peripheral side faces thereof.
The bearing plates (21a) on the drive side include the bearing hole (28) for rotatably bearing the load sheave (8), and the bearing plate (21b) on the speed reducing side include the bearing hole for rotatably bearing the load sheave and a speed reducing gear bearing hole (29) for bearing the speed reducing gear (10a). Numeral 22 designates the fixing bolt for fixing the bearing plates (21a, 21b) to the main body frame.
Bearing plate 21a includes the female thread 21a1 for screwing the fixing bolt (22), the bearing plate (21b) includes the insertion hole (21b1) of the fixing bolt and a plurality of the insertion holes (2c2) of the fixing bolts on an outer side of the space containing the load sheave of the main body frame (2c).
Where the main body frame is formed by aluminium diecasting, a sufficient fastening force of the fixing bolt is not ensured and, therefore, a method of forming the female thread at the bearing plate made of steel is an optimum constitution in view of strength and in view of small-sized formation.
Further, by integrating the bearing plate made of steel separably by the fixing bolt, the constitution is suitable also for separation in accordance with a material when a product is abandoned.
The hand wheel (16) is provided with a space having a length substantially the same as a width of an inner periphery of the hand wheel between an inner peripheral face thereof and an outer periphery of the drive member. The space is inwardly provided with the rotation drive member engaged with the drive member (17) and the hand wheel (16) for transmitting driving of the hand wheel to the drive member.
The ratchet (14) is engaged with the claw (13) and is axially supported by the pressure receiving member (12) rotatably only in a hoist up direction.
When the hand wheel is rotated in the hoist up direction by a drive member screwed with the male screw (12a) formed at a cylindrical portion of the pressure receiving member, the drive member presses the brake plate (15) to the ratchet along with the pressure receiving member (12) and drives to rotate the drive shaft in the hoist up direction.
Hand wheel
When the hand wheel is rotated in a hoist down direction, the drive member (12) is displaced in a direction of loosening the brake plate (15) from being pressed to the ratchet wheel and, therefore, the ratchet wheel is separated from the pressure receiving member (12) and the drive member (17).
Therefore, the drive shaft is pivoted in the hoist down direction. The drive shaft (9) and the pressure receiving member (12) are engaged to be unable to rotate relative to each other by serrations.
In the above-described constitution, the main body frame (2) of the hoist is molded by diecast molding using an aluminium alloy or molded by an engineering plastic.
As shown by Figure 3b and Figure 4, the connecting frame (2c) contains the load sheave by a space surrounded by the connecting frame (2c).
An inner wall of the connecting frame (2c) forming the space of containing the load sheave (8) is formed with the guide groove (2c1) for guiding the load chain (5) to be wound around the load sheave.
A port of guiding in/out of the load chain (5) of the load sheave containing space is arranged with the chain guide (25) for guiding in and out the load chain (5) to and from the load sheave.
The chain guide is provided with the cross-shape guide hole (26), the width of which is made to be wider than a width of a link of the load chain to guide the load chain.
The guide hole includes the longitudinal link guide hole (26a) and the transverse link guide hole (26b) on an inner side of the longitudinal link guide hold.
As shown by Figure 5, the hand wheel cover (3a) attached to the drive side frame (2a) of the main body frame (2) includes a portion of covering a front face of an end face of the hand wheel (16) and covering about a half of an outer periphery of the hand wheel (16), and the hand chain guide in/out port (33) opened to a direction of feeding out the hand chain (6).
About the patent
US patent number 7,614,610 was awarded to Desheng Xia and Koji Koyam (the assignee is Kito Corporation, of Yamanashi, Japan) on November 10, 2009. Application number 11/920,539 was filed on June 5, 2006.
Disclaimer
As edited versions of the originals, this article and accompanying drawings may omit legally or technically important detail.
Figure 1a is a front view of a hoist according to the invention; b is a side view thereof.
Figure 3a is a sectional view taken along a line C-C of Figure 2; b is a sectional view taken along a line D-D of Figure 1a. Figure 4 is a G-G arrow mark view of Figure 1a.
Figure 5 is a sectional view taken along a line E-E of Figure 3a.
Figure 6 is a sectional view taken along a line F-F of Figure 3a.
