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Патент USA US3062507

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Nov. 6, 1962
R. s. SELSET
3,062,505
RATCHET HOIST
Filed July 20, 1961
INVENTOR.
RON/9L0 5. SELSET'
BY
, YAQQ‘IQ/
ATTO R N EYS
ice
3,062,565
Patented Nov. 6, 1962
1
2
3,062,505
Employing similar reference characters to designate cor
responding parts, the numeral 17 represents one of two
checks of a cast cheek-frame. A winding drum occupies
RATCIFET HOIST
Ronald S. Selset, Seattle, Wash, assignorto Beebe Bros.
Seattle, Wash, a partnership
Filed July 20, 1961, Ser. No. 126,806
5 Claims. (Cl. 254-167)
This invention relates to an improved ratchet hoist of
the opening between the cheeks of said frame and is
?xed to a cross-shaft 18 having its ends journaled for r0
tation in said cheeks. The winding surface 19 of the
drum has ‘an integral ratchet wheel 21 at one end thereof.
The wire spring, designated generally by 60, to which the
the type illustrated and described in pending application
improvements of the present invention are directed works
of Dan D. Beebe for Letters Patent of the United States 10 in a space which is provided between the ratchet wheel
and the adjacent cheek.
?led April 25, 1960, Ser. No. 24,466, and namely a
A yoke 22 straddles the cheek-frame with its two arms
ratchet hoist providing a winding drum having a ratchet
pivoted to protruding ends of the cross-shaft, and beyond
wheel on one end thereof and employing with said ratchet
the edge limits of the cheek-frames a shaft 32 extends be
wheel two pawls, one a feed pawl pivotally carried by a
yoke swingable by hand in reciprocal motion about the 15 tween the yoke arms. A feed pawl 33 is freely pivoted on
center of the winding drum as an axis, and the other a
this shaft 32 but is held against endwise travel, being posi
holding pawl pivotally carried by a frame in which the
winding drum is journaled. The said ratchet hoist em
tioned so as to occupy the substantial plane of the ratchet
wheel so that a dogging end 34 of the pawl engages the
teeth of the ratchet wheel. The pawl can be biased either
ploys two springs, one a single duty and the other a double
duty spring. in the operation of winding cable upon the 20 into or out of engagement with the ratchet wheel by means
drum the single-duty spring urges the feed pawl into en
gagement with the ratchet wheel while the double-duty
spring urges the holding pawl into engagement with the
wheel so that the latter will alternately ratchet and catch
of a manually controlled spring 37 ?ipped against either
motion, the feed pawl perforce catching and ratcheting in
the respective instance. The operation of unwinding cable
from the drum is obtained by “dropping” off single teeth
is made concave in cross-section to provide a groove 49.
in each of a succession of short reciprocations of the yoke.
plane which is occupied by such main shaft. A holding
pawl 43 for the ratchet wheel is pivoted intermediate its
ends to the shaft, the pawl being properly positioned by
of two horns 35 or 36, selectively. The dogging end of
the pawl has an car 41 jutting laterally therefrom into
the space hereinbefore referred to which is occupied by
relative to the teeth of the wheel while the yoke is swung, 25 the spring 60. This car has an arcuate bottom pro?le
respectively, in its forward and return directions of swing
when viewed from the side, and this arcuate bottom edge
To accomplish this action the single-duty spring is made
inactive to the feed pawl, while the double-duty spring
Below the winding drum a cross-shaft 42 extends paral
lel to the main shaft 18 in approximately the same vertical
a snap-ring 44. One arm 45 of the pawl provides a
acts upon both pawls. In this said action, and as a conse
quence of the fact that there is an intermittent engagement
buttress tip, and the wire spring 60 urges this tip into
and disengagement as between the feed pawl and the 35 dogging engagement with the ratchet wheel. The other
double-duty spring, a rubbing action takes place between
arm 47 of such holding pawl limits the retraction travel
the two. The spring wire of which the double-duty spring
is composed has been heretofore subject to considerable
wear.
The life span has not been unduly long and the
of the dogging tip by being brought to bear against a stud
5t) rooted in the proximal check of the frame. The
dogging tip is retracted either manually by lifting said
springs must be continually inspected to insure replace
arm 47 or by the act of bringing the ear 41 of the feed
ment before breakage can occur.
pawl downwardly against the spring 60, which will be
Considerable hazard
is present should breakage take place while the hoist is in
service.
For its principal object the present invention aims to
now described.
The wire composing said spring is provided with a
multiple-turn loop 61 which, in the application of the
provide a ratchet hoist of the above nature in which the 45 spring to the ratchet hoist, slips over said stud 56.
presently used double-duty spring is replaced by a wire
spring of perfected design and one, especially, which is
A
short branch 62 of the spring lies uppermost and extends
inwardly from the loop in the substantial plane of the
subject to such negligible wear that the life of the spring
groove 49 so as to be lodged in the latter by the act of
exceeds the normal life of the hoist.
bringing the feed pawl 33 downwardly. A considerably
50
The invention has the further object of designing a
longer branch of the spring extends from the lower side
wire spring, to perform such double duty, which will
of the loop parallel, or approximately parallel, to the
continue to perform its single duty of maintaining the
branch 62 and is itself looped intermediate the ends.
holding pawl in functioning condition even in the un
This latter loop, designated by 63, is brought upwardly
likely event that breakage should occur in the branch
and thence downwardly through an approximate 225 ‘’
of the spring which is subject to rub from the feed pawl. 55 turn about a center paralleling the center of the loop 61
The above and other objects and advantages in view
and produces a free section 64 which crosses the root
will appear and be understood in the course of the fol
section 65. The extremity 66 of the free section 64 is
lowing description and claims, the invention consisting
bent inwardly parallel to the axes of the loops and is
in the novel construction and in the adaptation and com
caught in a side socket of the holding pawl. In order
60
bination of parts hereinafter described and claimed.
- for said extremity to be caught in the side pocket it is
In the accompanying drawing:
necessary to force said free section outwardly in relation
FIGURE 1 is a fragmentary longitudinal vertical sec
to the root section 65, responsively tensioning the free
tional view illustrating a ratchet hoist constructed to em
section so that the dogging end of the holding pawl is
body preferred teachings of the present invention.
yieldingly urged radially inwardly into ratcheting engage
FIG. 2 is a fragmentary transverse vertical sectional 65 ment with the ratchet wheel. Depression of the short
view thereof on line 2—2 of FIG. 1.
branch 62 acts counter to said spring thrust to move the
FIG. 3 is a side elevational view of the spring employed
in the present invention; and
dogging end of said pawl radially outwardly.
The functioning relationship between the two pawls is
FIG. 4 is a top plan view of said spring.
The disclosure of the above-identi?ed patent application 70 as follows:
Upon reciprocally moving the yoke in a counterclock
is relied upon to fully illustrate and describe the character
of ratchet hoist to which the present invention pertains.
wise direction, considered from the vantage point of FIG.
3,062,505
3
1, the feed pawl lodges behind a tooth of the ratchet wheel
and causes the drum to responsively turn in a cable-wind
ing direction, the holding pawl 43 simply ratcheting over
successive teeth as spring 68 performs its normal func
tion of biasing the dogging arm‘ 45 against the wheel.
In the clock-wise return motion the holding pawl lodges
against a tooth of the wheel while the feed pawl ratchets
over the then stationary teeth.
Should it be desired to
connection of the spring with the holding pawl can be
made only by expanding said angle to tension the loop
of the spring.
2. Structure as recited in claim '1 in which the extrem
ity of the spring’s free section is bent at substantial right
angles to the parent section and lodges in a mating side
pocket of the holding pawl to provide said attachment
between the spring and the holding pawl.
3. Structure as recited in claim 1 in which the direct
let out the cable while under load the action is performed
by short-stroke reciprocal motion of the yoke at the low 10 engagement between the spring and the feed pawl is pro
vided by an car which juts laterally from the pawl and
end of its permitted travel. Backing off one tooth at a
has an arcuate bottom pro?le when viewed from the side
time, the ear 41 of the feed pawl in this case acts during
and which is made concave in cross-section. to provide a
the counter-clockwise stroke to press downwardly against
groove in which said short branch of the spring seats.
the short branch 62 of spring 68. This responsively re
4. The structure recited in claim 1 characterized in that
tracts the dogging end 45 of pawl 43 from the ratchet 15
the bend which produces the loop within said long branch
wheel and as the yoke is then swung backwardly (clocks
of the spring has an approximate 225° development caus
wise) a distance of one tooth or more the ratchet wheel
ing the free section to cross the root section.
responsively backs off in unison a single tooth before the
5. in combination with a frame, a ratchet wheel carried
ear releases the spring 60 and permits the latter to again
for rotation by the frame, a lever carried by the frame for
perform its normal function of pressing the holding pawl
forward and return swing motion about an axis coincid
against the ratchet wheel.
ing with the'rotary axis of the wheel, a feed pawl for
The invention and the manner of its operation should
the ratchet wheel carried for pivotal motion by the lever,
be clear from the foregoing. Minor changes in the details
and a holding pawl carried by the frame for pivotal motion
of constructoin can be resorted to without departing from
into and out of ratcheting engagement with the ratchet
the spirit of the invention, wherefor it is my intention that
wheel in a position spaced a moderate distance beyond a
no limitations be implied and that the hereto annexed
predetermined end limit to which the feed pawl travels
claims be given the broadest interpretation to which the
in its forward swing motion: a wire sear spring pivoted
employed language fairly admits.
to a frame-carried pin for rocker motion about an axis
What I claim is:
1. In combination with the'cheek-frame, winding drum, 30 which parallels the rotary axis of the Wheel and lies be
tween the holding pawl and said predetermined end limit
ratchet wheel, yoke, feed pawl, and holding pawl of a
of the feed pawl’s travel so that the spring occupies a
ratchet hoist of the character described in which the wind
position in the path travelled by the feed pawl and acts
ing drum and the ratchet wheel turn in unison and are
normally to yieldingly press the holding pawl into ratchet
journaled for rotation between the cheeks of the frame,
ing engagement with the ratchet wheel while serving addi~
the yoke is journaled for reciprocating forward and return
tionally to retract the holding pawl out of said ratcheting
swing motion about an axis coinciding with the rotary
engagement and at the same time yieldingly press the
axis of the drum, the feed pawl is carried for pivotal
feed pawl into ratcheting engagement with the ratchet
motion by a shaft extending between the arms of the yoke
wheel for the working interval necessary to back off said
and is biased into ratcheting engagement with the ratchet
ratchet wheel a single tooth as the lever initially swings
wheel, and the holding pawl is carried for pivotal motion
in its return stroke of reciprocation, the wire of which
into and out of ratcheting engagement with the ratchet
said spring is composed being formed within its length
wheel by a shaft extending transversely between the cheeks
with a coil which slips over the frame-carried pin and
of the frame below the drum: a wire sear spring pivoted
divides said spring wire into long and short branches both
to a pin which is carried by the frame to occupy a posi
tion spaced above the last-named shaft in the path 45 extending inwardly from the coil in a direction which is
generally radial to the wheel and with the long branch
travelled by the feed pawl and acting normally to yield
lying proximal and the short branch lying distal to the
ingly press the holding .pawl into ratcheting engagement
holding pawl placing the short branch in a position to be
with the ratchet wheel and serving additionally to retract
engaged directly by the feed pawl as the latter nears the
the holding pawl out of said ratcheting engagement and
at the same time yieldingly press the feed pawl into 50 end limit of its forward travel, the long branch being
formed with a bend intermediate its ends developed on
ratcheting engagement with the ratchet wheel for the
an axis paralleling that of the coil to divide the long
working interval necessary to back off said ratchet wheel
branch into a root section and a free section of which
a single tooth as the yoke initially swings in its return
the latter extends toward the holding pawl in acute
stroke of reciprocation, the wire of which said spring is
composed being formed within its length with a multiple 55 angular relation to the root section, interengaging means
being provided by the free section of the spring at its
loop coil which slips over the frame-carried . pin and
extreme outer end and by the dogging end of the holding
divides said spring wire into long and short branches both
pawl for detachably connecting said extreme outer end
extending inwardly from the coil in a direction which is
to said dogging end, the element of said interengaging
generally radial to the drum and with the short branch
means which is provided by the holding pawl being so
lying uppermost in a position to be engaged directly by
located upon the pawl that the connection of the spring
the feed pawl as the latter nears the end limit of its for
with the holding pawl can be made only by expanding said
ward travel, the long branch being formed with a loop
acute angle to tension said bend of the spring.
intermediate its ends developed on an axis paralleling that
of the coil to divide the long branch into a root section
and a free section of which the latter extends downwardly 65
from the loop at an angle of approximately 45° from the
root section, interengaging means being provided by the
free section of the spring at its extreme outer end and by
the dogging end of the holding pawl for detachably con
necting said extreme outer end to said dogging end, the 70
element of said interengaging means which is provided by
the holding pawl being so located upon the pawl that the
References Cited in the ?le of this patent
UNITED STATES PATENTS
2,647,724
Cof?ng ______________ __ Aug. 4, 1953
2,738,954
2,854,852
2,890,857
2,913,224
2,927,771
Du Bois _____________ __ Mar. 20,
Clark ________________ __ Oct. 7,
Hoffman ____________ __ June 16,
Uhlig _______________ __ Nov. 17,
Clark ________________ __ Mar. 8,
1956
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