US3141353A

US3141353A - Load binding winch control mechanism

Info

Publication number: US3141353A
Application number: US201190A
Authority: US
Inventors: Robert H Gray
Original assignee: PREFERRED GROWTH CAPITAL Inc
Current assignee: PREFERRED GROWTH CAPITAL Inc
Priority date: 1962-06-08
Filing date: 1962-06-08
Publication date: 1964-07-21
Anticipated expiration: 1981-07-21

Description

July 21, 1964 FIG. I

R. GRAY LQAD BINDING WINCH CONTROL MECHANISM Filed June 8, 1962 INVENTOR. ROBERT H. GRAY u mwww ATTORN EY United States Patent 3,141,353 LOAD BINDING WINCH CONTROL MECHANISM Robert H. Gray, Portland, Oreg., assignor to Preferred Growth Capital, Inc., a corporation of Oregon Filed June 8, 1962, Ser. No. 201,190 8 Claims. (Cl. 74-577) This invention relates to new and useful improvements in control mechanisms for load binding winches or any form of winding shaft.

It is a primary object of the present invention to provide a novel arrangement of rotatable control member and latch operative with a winding shaft and capable of functioning wherein selectively to provide one-way operation of said winding shaft to bind a load, to provide for sequential, controlled unwinding of the shaft, and to provide for free release or uncontrolled winding of said shaft.

Another object is to provide a control mechanism for a winding shaft which is positive in operation and facilitates safety in use of the winding shaft.

Still another object is to provide a control mechanism for a winding shaft which is simple in structure, inexpensive to manufacture, and rugged in operation.

Briefly stated, the control mechanism comprises a rotatable member in the form of a ratchet wheel and a latch member associated therewith in the form of a pawl wherein the ratchet wheel forms an integral part of a winding shaft or drum and the pawl has a plurality of positionssome of which function to control operation of the ratchet wheel. In a first position, the pawl permits one-way winding or load binding rotation of the ratchet wheel; in a second position the pawl provides for sequential, controlled unwinding of the ratchet wheel and drum; and in a third position provides for free release or uncontrolled unwinding of the ratchet wheel. The first two positions of the pawl comprise over-center positions accomplished by spring means operative thereon. The pawl is held in the third position by a stop member.

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 and wherein:

FIGURE 1 is a side elevational view, with parts broken away, of a load binding winch incorporating the present control mechanism;

FIGURE 2 is an end elevational view showing two positions of the pawl in the control mechanism, one of which is shown in full lines and the other of which is shown in dotted lines; and

FIGURE 3 shows a third position of the pawl.

Referring now in particular to the drawings, the present control mechanism is operative in conjunction with load binding means such as a winch having a body portion provided with

side walls

12 and 14 which support therebetween a rotatable winding shaft or drum 16. Body portion 10 has bottom apertures 18 for the reception of fastening means if desired to attach the winch to a support. One end of winding drum 16 integrally carries an apertured lever engaging drum 20 for rotating the drum, and the opposite end of the drum integrally carries a ratchet wheel 22.

The ratchet wheel 22, in accordance with the present invention, is of novel construction employing pairs of teeth 24 between each pair of which is disposed a tooth 26 of greater length than teeth 24. Thus, it is apparent that the outer ends of

teeth

24 and 26 operate at different radial distances in the same plane. Although the arrangement of

teeth

24 and 26 is illustrated as comprising two teeth 24 to one tooth 26, it is to be understood that such different length teeth may be one to one or may 3,141,353 Patented July 21, 1964 be three or more teeth 24 to one tooth 26, depending upon a desired sequential unwinding function as will be more apparent hereinafter.

Associated with the ratchet wheel 22 is a pawl 30 journaled on a bolt or pin 32 supported in the end wall 14 of the winch and also in an upturned tab 34 forming a part of an end housing 36 on the body portion 10 of the winch. Pawl 30 has a downwardly projecting edge portion 38 engageable with a leaf spring 40 supported at its opposite ends on shoulders 42 provided interiorly of the housing 36. Housing 36 has an opening 44 intermediate the shoulders 42 to permit downward flexing of the leaf spring.

The arrangement and structure of the pawl 30 and spring 40 are such that said pawl element is movable to and maintained in a pair of over-center positions, such over-center positions being shown in full and dotted lines in FIGURE 2.

Pawl 30 has two

teeth

48 and 50 disposed in spaced relation, the first of which is adapted to engage the tooth slots of the ratchet wheel to control operation of the ratchet wheel and the second of which is adapted for engagement only by the elongated teeth 26 of the ratchet wheel in an unwinding operation for rotating the pawl from one of its over-center positions to the other. More particularly, the pawl teeth are constructed and arranged and the pivot point of the pawl is such that in a first over-center position of the pawl, i.e. in the full line position of FIGURE 2, tooth 48 engages the toothed slots of the ratchet wheel and as the pawl is spring loaded it allows the ratchet wheel and load binding drum to be operated one tooth at a time in a load binding direction, i.e. in the direction of arrow 52, FIGURE 2. In this over-center position of the pawl 30, its tooth 50 is out of the plane of all the teeth of the ratchet Wheel.

Tooth 50 of the pawl is operative with the elongated teeth 26 on the ratchet wheel to unwind the drum sequentially. In an unwinding operation, i.e., in the direction of arrow 54 in FIGURE 2, the pressure is first released from the drum by slight rotation of lever engaging drum 20 in the direction of arrow 52 to release the tooth 48 from the ratchet wheel and then the pawl is rotated counterclockwise to its second over-center position as shown in dotted lines in FIGURE 2, the pawl having a finger-engaging tab 56 projecting laterally from the housing for convenient engagement by the operator. In this second over-center position, tooth 48 is out of the plane of all the teeth of the ratchet wheel but tooth 50, while out of the plane of teeth 24 is in the plane of teeth 26. Thus, as the drum unwinds, a tooth 26 of the ratchet wheel engages tooth 5t) and rotates the pawl back to its first over-center or full-line position to bring tooth 48 into engagement with the ratchet wheel and stop it.

By repeatedly accomplishing the above unwinding step, the drum is unwound sequentially in a controlled function.

At times it may be desired to release completely the ratchet wheel 22 from the pawl to provide for uncontrolled unwinding of the drum, and for this purpose a rotatable stop 58 is mounted on the winch housing adjacent the pawl 30, the rotatable mounting being accomplished by a pin 60 supported in the end wall 14 of the winch body portion 10. Stop 58 has an end abutting edge 62 which is adapted for engagement with a flat edge 64 on the pawl 30 leading from the tooth 50. In the normal winding and sequential unwinding positions of the pawl the stop 58 is rotated to an upright position as shown in FIGURE 2, the stop having a finger engaging tab 66 to accomplish rotation thereof. However, for free rotation of the drum the stop 58 is rotated counterclockwise almost to a position adapted for'engagement with the edge 64 of the pawl, as shown in FIGURE 3.

The parts are dimensioned such that in this intermediate position both

teeth

48 and 50 of the pawl are out of the plane of the ratchet wheel teeth which of course allows free rotation of the drum and release of the load on the winch.

In the intermediate FIGURE 3 position of the pawl it is substantially centered between its two over-center positions and the friction of spring 40 on the projection 38 holds the pawl in such position and prevents it from rotating counter-clockwise.

Thus, in accordance With the present invention there is provided a control mechanism by means of which a cable may be ratchet wound on the drum, and for release purposes the drum may be unwound sequentially through a distance dependent upon the number of elongated teeth 26 on the ratchet wheel, or it may be unwound freely. Such mechanism facilitates convenience in operation of the winch. This mechanism also facilitates safe use of said winch in that by suitable operation of the pawl a positive sequential unwinding is accomplished, and if desired each sequential Winding step may operate through more than one tooth of the ratchet wheel.

It is to be understood that the invention may take other forms than that shown and that all such modifications and variations within the scope of the appended claims which will occur to persons skilled in the art are included in the invention.

Having thus described my invention, I claim:

1. Control mechanism in combination with a winding shaft comprising a rotatable member integrally connected to said shaft, a pair of sets of projections on said rotatable member operable at diiferent radial distances in the same plane, a latch member pivotally operable between first and second positions, said latch member in the first position thereof being engageable by all of said projections to provide one-way forward winding of said shaft, and in the second position being engageable by one set of projections only upon reverse rotation of said shaft to return said latch member to its first psition.

2. The control mechanism of claim 1 wherein said rotatable member comprises a ratchet wheel and projections comprise teeth thereon.

3. The control mechanism of claim 1 wherein rotatable member comprises a ratchet wheel and projections comprise teeth thereon and wherein latch member comprises a pawl.

4. The control mechanism of claim 1 wherein said rotatable member comprises a ratchet wheel and said sets of projections comprise teeth some of which are longer than others to operate at said different radial distances in the same plane.

5. The control mechanism of claim 1 wherein said first and' second positions of said latch member comprise over-center positions, and spring means operative on said latch member to hold the latter in said overcenter positions.

6. The control mechanism of claim 1 wherein said latch member has a pair of teeth members one of which is engageable by all of said projections to provide said one-way winding of said shaft and the other of which is engageable by one set of said projections only for returning said latch member to its said first position.

7. The control mechanism of claim 1 including stop means adapted to engage said latch member and hold the latter in a position intermediate its two positions, said latch member in said intermediate position being out of the plane of said projections to allow free unwinding of said shaft.

8. The control mechanism of claim 7 wherein said stop means is pivotal between are inoperative position and a position for engagement with said latch member.

said

said said References Cited in the file of this patent UNITED STATES PATENTS 1,270,809 Freeman July 2, 1918 2,941,627 Beebe on June 21, 1960 2,990,159 Haferkom June 27, 1961 FOREIGN PATENTS 943,417 France Oct. 4, 1948

Claims

1. CONTROL MECHANISM IN COMBINATION WITH A WINDING SHAFT COMPRISING A ROTATABLE MEMBER INTEGRALLY CONNECTED TO SAID SHAFT, A PAIR OF SETS OF PROJECTIONS ON SAID ROTATABLE MEMBER OPERABLE AT DIFFERENT RADIAL DISTANCES IN THE SAME PLANE, A LATCH MEMBER PIVOTALLY OPERABLE BETWEEN FIRST AND SECOND POSITIONS, SAID LATCH MEMBER IN THE FIRST POSITION THEREOF BEING ENGAGEABLE BY ALL OF SAID PROJECTIONS TO PROVIDE ONE-WAY FORWARD WINDING OF SAID SHAFT, AND IN THE SECOND POSITION BEING ENGAGEABLE BY ONE SET OF PROJECTIONS ONLY UPON REVERSE ROTATION OF SAID SHAFT TO RETURN SAID LATCH MEMBER TO ITS FIRST POSITION.