Load chain end stop

An end stop for a link chain hoist (10) in which a ring (28) is received through the opening (22a) of the next-to-last load chain link (20a) on one side of the third last link (20c), with the last load chain link (20b) received in the opening (22a) on the other side of the third last link to force the next to the last link sideways relative to the remainder of the load chain to define an end stop engageable with the chain guide (16) of the hoist.

The present invention relates to an improved end stop for preventing the 
loose end of a hoist load chain from running through a hoist chain guide. 
U.S. Pat. No. 3,810,359 discloses an end stop wherein a pull link is fixed 
to the last link of a link type load chain to maintain the last link in a 
sideways position in relation to the next-to-last link. The last link is 
thus arranged to engage the chain guide of the hoist to prevent passage of 
the loose end of the chain therethrough. The pull link also serves to 
facilitate pulling the load chain through the hoist. The main advantages 
of using one of the chain links as an end stop are that the end stop, 
being a hardened chain link, does not tend to become forced into the chain 
guide, and that a relatively low-cost, soft pull link can be used. 
The present invention is an improvement over the end stop disclosed in the 
above patent in that it uses the last load chain link in combination with 
a simple pull ring to turn the next-to-last load chain link sideways, thus 
eliminating the need for a specially formed pull link to turn the last 
link sideways. The pull link contemplated can be a stock ring of the type 
heretofore used as a combination pull ring and chain stop, so that no 
additional tooling is required to form and apply the pull link.

Referring to FIG. 1, there is illustrated a hand lever hoist 10 including a 
body 12 enclosing a chain-engaging sheave (not shown), an operating lever 
14, a chain guide 16, and a load chain 18. Hoists of this type are 
well-known in the art, and the hoist per se will not be described in 
greater detail herein. Also, it will be apparent that the present 
invention is applicable to other types of link chain hoists as well. 
The load chain 18 is a standrad, high-strength chain commonly used in hoist 
applications, and comprises a plurality of welded links 20 interfitting 
with openings 22 of adjacent links in end to end relationship. In 
accordance with known design practice the length of each chain link 20 is 
substantially greater than its width. The chain 18 has a load hook 23 
attached to one end, while the other end hangs free. 
Referring particularly to FIG. 2, the chain guide 16, which can be formed 
as part of the hoist body 12, or attached thereto, includes guide openings 
24 which are of clover leaf or cross-shaped configuration to insure that 
the adjacent chain links 20 are properly aligned perpendicularly to one 
another for passage into the hoist body in engagement with the load 
sheave. The end stop of the present invention, designated generally by the 
numeral 26, comprises a pull ring 28 received through the opening 22a of 
the next-to-last load chain link 20a, and the last load chain link 20b, 
also received through the opening 22a. Referring particularly to FIGS. 2 
and 3, when the end stop 26 is assembled the pull ring 28 and the last 
link 20b are arranged such that they are received on either side of the 
third last link 20c so that the next-to-last link 20a is forced sideways 
relative to the rest of the load chain 18. 
When the hoist 10 is operated, and a load engaged by the hook 23 is lowered 
until the next-to-last link 20a reaches the chain guide 16, the sideways 
oriented next-to-last link will engage the chain guide 16 as shown in 
broken line in FIG. 3. Since the sideways oriented link 20a is a part of 
the hardened load chain 18, it will not tend to enter into the chain guide 
16. 
Since the pull ring 28 never contacts the chain guide 16, it can be formed 
as a split ring of a relatively soft material which can be easily 
assembled to the load chain 18 after the chain is run through the openings 
24 and over the load sheave. The ring need not be formed in any special 
shape and can be a relatively soft material of a diameter suitable for the 
size of load chain used and of a diameter suitable for pulling an unloaded 
chain through the hoist by pulling the ring by hand.