US1740782A

US1740782A - Safety hook

Info

Publication number: US1740782A
Application number: US311287A
Authority: US
Inventors: James P Ratigan
Original assignee: Individual
Current assignee: Individual
Priority date: 1928-10-09
Filing date: 1928-10-09
Publication date: 1929-12-24
Anticipated expiration: 1946-12-24

Description

Dec. 2 4, 1929. t J, P, RATIGAN 1,740,782

SAFETY HOOK Filed Oct. 9, 1928 Patented Dec. 24, 1929 UNITED STATES PATENT QFFICE `SAFETY HOOK Application filed October 9, 1928.

This invention relates to safety hooks of the type useful, for example, in pulling' sucker rods and for other purposes around lan oil well. i

5 One of the objects of the invention is to insure against accidental detaching of the hook from the object connected there-with.

This invention is an improvement over Patent No. 1,522,979 issued to me January 13,

An important obj ect of the invention is to facilitate opening and closing of the latch.

Another object is to provide a latch operating mechanism of which the manual operating member is positioned longitudinally of the shank of the hook so that retraction of the latch can be accomplished with the same hand that grasps the shank in the act of engaging and disengaging the hook from an object such, for example, as a string of sucker rods.

Other objects and advantages will appear in the subjoined detailed description.

The accompanying drawings illustrate the invention 1 is a front elevation of a safety hook constructed in accordance with the provisions of this invention.

F ig. 2 is a View, mainly in vertical section 30 on the line indicated by 2 2 of Fig. 1.

rThere is provided a hook comprising a slotted head 3 and a shank or stem 4. The slot in the head is indicated at 5.

The head 3 is provided with a chamber 6 that, in this instance, extends aslant upwardly and rearwardly away from the tip 7 of the hook.

The chamber 6 is rectangular in cross-secti-on and slidably mounted therein is a latch 8 that is also rectangular in cross-section. When the latch is in the closed position, as shown in Fig. 2, it projects across the slot 5 approximately in engagement with the tip 7.

A suitable mechanism is provided to hold the latch in latching position and to retract said latch, and said mechanism includes an operating member 9 pivoted'at 10 to the stem 4 and accommodated within a chamber 11 extending lengthwise of the stem. The chamee n.,

Serial No. 311,287.

ber 11 opens to the rear face of the stem 4 so that, normally, the operating member 9 can project from the chamber 11, thus enabling the operating member 9 to be readily retracted into the chamber 11 by the operators hand 55 when the hand grasps the stem 4 in the act of moving the hook toward and from the object that is to be connected with the hook.

Between the member 9 and the latch 8 is an intermediate latch operating member 12 that, CO in this instance, constitutes a lever of the first class, the fulcrum of which is indicated at 13. The fulcrum 13 is supported in the side walls of the chamber 11. The upper arm 14 of the lever, preferably, terminates in a CJ rounded portion 15 which is engaged by a slot 16 in the forward edge of the operating niember 9. The arm 14 extends aslant rearwardly and upwardly. Y

The lower end of the chamber V11 communi- 7G cates with the chamber 6 so that the lower arm 17 of the lever 12 can projectfroni the chamber 11 into the chamber 6. The arm 17 projects into a recess 18 in the latch 8 so that swinging of the lever will `actuate the latch. 7U

It is to be noted that the lower end '19 of the lever arm 17 is approximately at right angles to the longitudinal axis of said lever arm and, thus, if the front wall of the recess 18 strikes the end 19, the resultant pressure is S0 toward the fulcrum 13, thus making it impossible to retract the lever 12 by pressure of the latch thereagainst. It follows from this that any member that is caught in the slot 5 can not escape from said slot by bearing against the latch, since the lever 12 locks said latch in closed position until released by actuation ofthe operating member 9. The stem 4 forms yat one end a reduced stud `2O terminated at its lower end by a lshoulder 21 that 90 seats against the under face of a cross-bar 22 provided with a hole 23 through which the stud 2O projects. The upper end of the stud 2O is provided with a head 24 which may be a nut screw-threaded on said stud. Between 9d the nut 24 and cross-bar 22 is a bearing 25 which, in this particular instance, is of the roller type. Thus the hook stem 4 and crossbar 22 have a swivel connection so that relative rotation between them may take place.

Projecting upwardly from one end of the cross-bar 22 is a slotted member 26, and pivoted to said slotted member by a pin 27 is a U-shaped arm 28, said arm projecting into the slot 29 of the member 26.

One end of the arm 28 is releasably connected by a pin 30 which extends across a slot 31 in the upper end of a member 32 that projects up from the cross-bar. The members 26, 32 are at opposite ends of said crossbar and the pin 27 and slot 29 constitute a hinge for hingedly connecting the arm 28 with the member 26. Any suitable means as', for example, a cotter key 33 may be employed in the pin 30 for retaining said pin against accidental displacement from the members that it engages.r

From the foregoing it will be readily understood that the invention operates as follows:

rlhe hook will be attached to the tackle, with which it functions, by swinging the arm 28 into open position, after which said arm will be closed and fastened. `When it is desired to secure the hook to the eye of a tool, the bight of a cable, or the like, the operator will grasp the stem l in one hand, thus forcing the operating member 9 inwardly so as to retract the latch 8. He will then swing the hook into position to engage the slot 5 with the object that is to be handled by the hook, and he will then relieve the pressure of his hand on the member 9, thus permitting the latch 8 to slide downwardly and forwardly into position to close the space between 'the heel and toe of the hook.

Though gravity, alone, may be depended upon for closing the latch 8, it is preferable, for quick action, that gravity be not depended upon for this purpose, but that a spring be utilized and, for this reason, it is preferable to employ the coil spring 34: which, in this instance, is positioned between the front edge of the operating member 9 and the front wall of the chamber 11 so that the expansive force of said spring will tend to hold the member 9 in the retracted position shown in 2. Release of the hook from the object engaged thereby will be accomplished by the operator again gripping the stem 4l and pressing inwardly the operating member 9.

Itis-to be particularly noted that the shorter lever arm 14 is engagedby the operating member 9 and the longer lever arm 17 eni gages the latch 8, thus amplifying the movement of the latch in relation to the movement of the operating member. Thus but a slight movement of the operating` mein-ber 9 is required to fully retract the latch.

If, for any reason, the object held by the hook should press upwardly and rearwardly upon the latch, when said latch is closed, as in Fig. 2, said latch will not be caused thereby to open because the direction of the pressure of the latch 8 on the lever arm 17 is such as to tend to shortensaid lever arm.

I claim:

1. A safety hook comprising a slotted head, a stem projecting from the head, a. latch slidably mounted in the head and provided with a recess and adapted to project into the slot, and a latch operating means including a pivoted arm projecting into the recess, the front wall of the recess engageable with the free end of the armat Aan angle that tends to shorten said arm when pressure is exerted against the latch in a direction to tend to retract said latch..

2. A safety hook comprising a head provided with a forwardly opening slot, said head provided with a chamber extending aslant upwardly and rearwardly away from said slot, a stem projecting from the head and provided wien a chamber extending lengthwise of the stem, said chamber opening to the rear face of the stem, a latch operating member pivoted at its upper end in the upper portion of the chamber, a spring yieldingly holding the operating member in position to project rearwardly out of the chamber so that pressure of the operators hand in grasping the stem will press said operating member further into the chamber, a latch slidably mounted in the chamber of the head and adapted to project across the forward end of the slot to close said slot, and a lever of the first class pivoted in the chamber of the stem, one of the arms of said lever eX- tending aslant rearwardly and upwardly into engagement with the operating member and the other arm of said lever extending downwardly into engagement with the latch.

3. A safety hook comprising a head provided with a forwardly opening slot, saidV head provided with a chamber extending aslant upwardly and rearwardly away from said slot, a stem projecting from the head and provided with a. chamber extending lengthwise of the stem, a latch slidably mounted in the chamber of the head and adapted to project across the forward end of the slot to close said slot, said latch provided with a recess, and a lever pivoted in the chamber of the stem, one arm of said lever normally hanging approximately vertical and the lower end of said arm being approximately at a right angle to the longitudial axis of said arm, said arm engaging in the latch recess and the front wall of said recess being substantially inengagement with said lower end of the lever arm when the latch is inposition to close the slot in the head, and a means in the chamber to operate the lever.

Signed at Los Angeles, Calif., this 28th day of Sept., 1928. JAMES P. RATIGAN.