US3077791A

US3077791A - Pawl and ratchet mechanism for load binding winch

Info

Publication number: US3077791A
Application number: US36075A
Authority: US
Inventors: Robert H Gray
Original assignee: Individual
Current assignee: Individual
Priority date: 1960-06-14
Filing date: 1960-06-14
Publication date: 1963-02-19
Anticipated expiration: 1980-02-19

Description

Feb. 19, 1963 I .52 I I l INVENTOR. ROBERT H. GRAY .1 "g m mm ATTORNEY se &

United States Patent 3,077,791 Patented Feb. 19, 1963 3,077,791 PAWL AND RATCHET MECHANHSM FUR LOAD BINDING WINQH Robert H. Gray, 4420 NE. Maywood Place, Portland, Oreg. Filed June 14, 1960, Ser. No. 36,075 1 Claim. (Cl. 74577) This invention relates to a slack take-up winch and more particularly pertains to a winch applicable for binding loads on a truck bed or the like.

It is common in present day shipping of logs, lumber, or other bulky loads for the load to shift or compact, with the result that the cable is loosened and the load either moves to a precarious position or completely falls from the vehicle. Furthermore, when a cable has become loosened, the load due to its momentum in shifting can readily snap the cable. This, of course, results in a loss of the load, as well as creating a hazardous condition for the vehicle operator or others in the area.

In the art of binding or cinching a load on a truck bed, freight car, airplane, etc., it is the usual practice to apply, in combination, tightening means and a non-elastic binding element such as a chain or cable. The cable is cinched taut around the load but no provision is made for maintaining the cable taut in the event the load shifts in a manner to decrease the necessary binding cable length therefor. v

' Another disadvantage of present day binding structures of the type described resides in their inability to be disconnected gradually, whereby the load is released suddenly. Such may create a dangerous condition for the person releasing the cable as a shifted and perilous position of the load may not be realized until after the load begins to fall.

In addition, load binders presently used have no provision for easily tightening a loose binding element after the original binding distance has lessened.

It is an objected of the present invention to provide a load binding winch which overcomes the disadvantages set forth above.

More particularly, it is an object to provide a load binding winch incorporating as a part thereof an automatic slack take-up means whereby an effective bind is provided on a load even though the load shifts to decrease the necessary binding length of the cable. Another object is to provide a load binding winch which is simple in construction but which isrugged in operation to prevent damage thereto by any normal or abnormal strain or impact.

Another object is to provide a load binding winch having slack take-up means which is wound simultaneously with the tightening of a binding cable.

' A further object is to provide a load binding winch having a novel ratchet structure employed therewith for effectively holding a drum against rotation in a load binding function but which provides for easy and gradual release of the drum.

A still further object of the present invention is to provide a winch of the type described having a ratchet mechanism for controlling rotation of a drum in a load binding function and being arranged to lock the drum in a non-rotative position in the event of failure of any part of the ratchet holding mechanism.

Briefly stated, the present invention is embodied in a winch structure employing a shaft fixed to a first ratchet wheel. A second ratchet wheel journaled on the shaft comprises an integral part of a winch drum and is connected to the first ratchet wheel solely by means of a torsion spring coiled around the shaft. The purpose of the torsion spring, when wound, is to take up any slack which may occur in a cable held taut by the drum, and the spring is sufficiently heavy and has suflicient coils to accomplish the desired purpose. Ratchet means are associated with the winch to allow take-up and release of tension on a cable, but if an added load is applied to the cable when it is in binding position, this load is supported by the ratchet means on the drum and is not applied to the spring. The design of the winch is such that by rotating the center shaft with a suitable lever the binding cable is wound on the drum and the spring is put under tension simultaneously.

The invention will be better understood and additional objects and advantages will become apparent from the following description taken in connection with the accompanying drawings which illustrate a preferred form of the device. It is to be understood, however, that the inven tion may take other forms and that all such modifications and variations within the scope of the appended claim which will occur to persons skilled in the art are included in the inventiton.

In the drawings:

FIGURE 1 is an end elevational view of a loaded truck bed and showing the present winch applied thereto;

FIGURE 2 is an enlarged sectional view of the Winch, taken on the line 2-2 of FIGURE 1;

FIGURE 3 is a sectional view of the present winch showing a portion of the ratchet assembly for controlling operation thereof, taken on the line 33 of FIGURE 2; and

FIGURE 4 is a plan .view of the winch showing a cable applied to the drum, taken on the line 44 of FIG. 2.

Referring now in particular to the drawings, the present winch employs a pair of

end plates

10 and 12 which may be fixedly anchored on a base plate 14, FIGURE 2, or if desired such plates may be affixed in suitable manner to a truclt bed, FIGURE 1. Plates l0 and 12 have axially aligned bores 18 receiving a shaft or turning bar 29, these bores serving as journals for rotative movement of the shaft 24). One end of the shaft projects beyond end plate 12 and is apertured at 22 for receiving a suitable handle or lever for turning the same.

integrally fixed to shaft 29, as by welding, is a ratchet wheel 26, this ratchet wheel having a suitable axial bore to receive the shaft. Wheel 26 is located between the end plates of the winch and has an aperture 28 disposed between the central bore and the outer periphery. A second ratchet wheel Si? is disposed at the opposite end of the winch and has a central bore 31 of a dimension to rotatably mount the wheel on the shaft. This ratchet wheel also has an aperture, designated by the numeral 32, disposed in a position intermediate the central bore and the periphery.

Referring particularly to the cross sectional configuration of the ratchet wheels 26 and 30 as shown in FIG- URE 2, it will be seen that these wheels have inwardly turned flange portions 34. Flange portions 34 serve an important function of reinforcing the outer toothed periphery of the ratchet wheels as well as to provide a wide toothed surface for ratchet dogs, to be described. The ratchet wheels thus are capable of holding a heavy force applied thereto.

Flange 34 on ratchet wheel 30 also facilitates securement thereto of a winch drum 36. For this purpose, the drum preferably has an outer diameter of a dimension to fit in the inner periphery of the flange 34 whereby there is thus presented sufficient connecting area for maximum rigidity. Flange 34- of wheel 30, in addition to providing a rugged construction for the wheel, thus provides an improved means of integral connection with the drum.

Drum 36 also extends into the flanged portion 34 of ratchet wheel 26 but the parts are not connected and in fact are dimensioned so as to permit relative rotation therebetween. A cable 38 is adapted to be attached to the drum and for such attachment the drum has a pair of books 49 and 42, best shown in FIGURE 4. The hooks are arranged with one hook offset peripherally from the other and with their open portions faced in the same direction, such direction being that opposite from the line of pull of the cable. To anchor the cable thereon, a free end is disposed in the hook 40 and then looped around book 42. Upon a single rotation of the drum :1 cable Wrapping is caused to overlie the cable end between the hooks to positively anchor it on the drum.

The opposite end of the cable 38 when applied to a truck bed is suitably connected to the other side of said bed from the winch. Such connection may be releasable if desired but in view of the easy attachment and detachment from the winch drum as explained above, the connection may be non-releasable and all disconnecting and connecting functions may be achieved, at the winch.

Mounted on the shaft intermediate the two ratchet wheels 26 and 30 is a torsion spring 44 having its opposite ends bent outwardly at 46. These bent ends are engaged in

apertures

28 and 32 of ratchet wheels 26 and 30, respectively, and thereby establish a drive connection between the two ratchets. I

Pivotally connected to opposite end plates and 12 by pivot pins 50 are ratchet dogs or

pawls

52 and 54, respectively, operatively engageahle to permit automatic rotation of ratchet wheels 30 and 26 in one direction only. Each of the ratchet dogs has a projecting hande portion 56 and a vertically thickened body portion 58. As best seen in FIGURE 3, the thickened body portion 58 of each dog has a tapered configuration and is dimensioned and located so as to serve as a wedge between the wheel and the base of the winch in the event pivot pin 50 on the dog breaks. As shown in FIGURE 3 of the drawing, the teeth of the ratchet wheels are canted in the operative direction of the unwinding of the cable 38, so that if the pivot pin fails, the teeth( already in engagement with the pawl 52, will force it into the space between the ratchet wheel and the base with a wedging action to prevent further rotation of the ratchet wheel. Such arrangement assures holding of the drum in a noni'otative position even though the pivot pin should fail.

Referring now in particular to the operation of the present device, it is mounted in a selected position on a truck bed, either on the bed as shown in FIGURE 1, or in any other suitable position such as in or between frame members of the truck. The free end of the cable is attached to the drum by means of hooks 4t) and 42. To tighten the cable, shaft 26 is rotated by a suitable lever engaged in holes 22. After the slack is taken out of the cable and the cable tightens relative rotation of the two ratchet wheels commences and the spring is thus loaded simultaneously with tightening of the cable 33. More particularly, in view of the fact that wheel 26 is an integral part of shaft 26 and is drive connected to wheel 30 solely by spring 44, resistance to rotation of the drum is taken up in the spring. When the spring is fully compressed, a mechanical connection is established between the input and output members.

Spring 44 has sufficient coils to allow at least one com plete and preferably more revolution of the wheel 26 relative to wheel 30 in winding. Spring 44, while allow ing such winding at the same time must be capable of applying a pulling force on the cable which is sufficient to securely bind a load. Such is accomplished by a combination heavy duty spring with sufiicient number of coils. Therefore, spring 24 is heavy enough to securely bind a load and yet has sufficient coils, shown as five in the drawings, to take up one or more rotations of the drum. Slack is thus readily taken up in the event the load or a portion thereof should shift, and by using a heavy duty spring, the force applied by the spring is sufficient throughout all of its tensioned condition so that a tight bind is maintained even though the spring is partly unwound.

For loosening the hind on the load the shaft and ratchet wheels are backed oil one notch at a time either by turning the shaft backwards by a handle a sufiicient amount to release a ratchet dog or by merely striking the under side of the ratchet dog handles 56. It is to be noted that ratchet wheel 30 and drum 36 are held against rotation in the one direction by the dog 52 whereby the binding cable is positively anchored against longitudinal movement in this one direction unless of course the ratchet dog is released. Such arrangement provides a rigid attachment in the one direction but one which automatically takes up slack if such should occur.

Having now described my invention and in what manner the same may be used, what I claim as new and desire to protect by Letters Patent is: n H

A slack take-up mechanism for a binding element comprising a base plate, a pair of spaced end plates on said base plate, a shaft journalcd in said end plates, a ratchet wheel having teeth on its periphery and being operatively connected to said shaft for rotation therewith, the axis of said ratchet wheel being parallel with said base plate and said ratchet wheel being positioned such that the teeth thereof are spaced a selected distance from said base plate to form a wedging area, a pivot pin mounted in one of said end plates and disposed between said ratchet wheel and said base plate, a pawl rotatably supported by said pivot pin for rotation between normal positions of engagement and disengagement with the ratchet wheel teeth, said pawl having a wedge-shaped portion of greater dimension than said selected distance but normally offset laterally therefrom, the teeth on said ratchet wheel being operatively directed toward said wedging area, whereby said pawl is arranged to be moved into the wcdging area to wedge between said ratchet wheel and said base plate and lock the ratchet wheel against rotation in the event of failure of said pivot pin.

References Cited in the file of this patent UNITED STATES PATENTS 606,760 Heisey July 5, 1898 1,431,401 Hupp Oct. 10, 1922 2,160,734 Henriksen May 30, 1939 2,738,204 Ibey Mar. 13, 1956 2,946,563 Eaton July 26, 1960