US2937550A - Wrench having spring-closed and leverlocked pivotal jaws - Google Patents

Description

y 1960 c. A. MILENTZ 2,937,550

WRENCH HAVING SPRING-CLOSED AND LEVER-LOCKED PIVOTAL JAWS FIGZ. Hes] FIGA.

United States Patent WRENCH HAVING SPRING-CLOSED AND LEVER- LOCKED PIVOTAL JAWS Charles A. Milentz, Box 131, High Ridge, M0. Filed Sept. 17, 1958, Ser. No. 761,580

2 Claims. (Cl. 81-91) This invention relates to wrenches having spring-closed and lever-locked pivotal jaws, and with regard to certain more specific features, to an open end, ratcheting wrench of this type, being an improvement upon the structure shown in my US. Patent 2,643,568, dated June 30, 1953.

Among the several objects of the invention may be noted the provision of a simple, reliable and rugged wrench of the class described having a very low number of parts of low cost, consisting simply of three main elements, two pivot means and a spring; the provision of a wrench of this class which has a ratcheting action but employs no toothed ratchet or pawl as such; the provision of a wrench of this class which is well balanced in the users hand and which is adapted easily to be applied to and removed from nuts and the like in crowded spaces, being applicable thereto either axially or transv-ersely of the threaded member carrying the nut; and the provision of a wrench of this class adapted for nondestructive application not only to hard nuts (such as :steel or the like) but also to soft nuts (such as of brass or the like). Other objects and features will 'be in part apparent .and in part pointed out hereinafter.

The invention accordingly comprises the elements and combinations of elements, features of construction, and arrangements of parts which will be exemplified in the structures hereinafter described, and the scope of which will be indicatedin the following claims. In the accompanying drawings, in which one of various possible embodiments of the invention is illustrated,

Fig. l is a plan view of the new wrench in an inopera- .tive position;

Fig. 2 is a right side view of Fig. 1;

Fig. 3 is a left side view of Fig. 1;

' Fig. 4 is a longitudinal section taken .on line 4'4 of Fig. I;

Fig. 5 is a transverse section taken on line 5.-5 of Fig. 1;

Fig. 6 is a view similar to Fig. 1, showing the wrench being applied to a nut;

Fig. -7 is a view similar to Fig. 6, showing completion .of the application of the wrench to the nut;

2. in application. The new wrench herein described fulfills these requirements, in addition to having good balance in the hand of the operator.

Referring now more particularly to the drawings, there is shown at numeral 1 a first jaw formed at its gripping end with two angular inner faces 3 and 5, the face onal nut, the inside of the finger 9 being adapted for partial engagement with a third face of such a nut. A nut of the class referred to is shown at N in Figs. 6-9, the type of engagement referred to being shown in Figs. 7 and 8.

The opposite end of the jaw 1 is provided with a central car 13, adapted movably to fit into a central slot 15 formed in the end of a handle 17, leaving adjacent side cheeks 16. A rivet pin means 19,.passing through holes in the cheeks 16 and ear 13, forms a free pivotal connection between the handle and the first jaw 1 Stop portions 21 on the jaw 1 and the handle 17 limit the motion of the jaw 1 in one direction of movement with respect to the handle 17 (see Fig. 6).

Fig. 8 is a view similar to Fig. 7, illustrating the driving sponding parts throughout the several views of the .drawtings.

An important consideration in any wrench construction is ruggedness and low cost, and that the number of parts shall be minimized, without sacrifice of convenience Between its two ends, the jaw 1 is provided with an ear 23 for interdigitation with an ear 25 of a second jaw 27. A rivet pin 29 having a center 30 forms a pivotal connection between the jaws, allowing free rotary movement between them.

The second or rocker type of jaw is provided at its outer end with inner faces 31 and 33, the face 33 terminating in a stop 35 and the face 31 terminating in a finger 37. The faces 31 and 33 are also adapted for engaging two adjacent faces of a hexagonal nut, the inside of the finger 37 being adapted for partial engagement with another face of such a nut. Stops 7 and 35 are engageable in the relatively closed positions of the jaws -1 and 27, as shown in Fig. 1. The end of the jaw 27 adjacent handle 17 is formed,

with an extending finger portion 39 having an outer notch 41. This notch in the relationship between the jaws 1 and 27 when they engage the sides of a nut N is adapted to be engaged by a lug 43 on the handle 17 when the handle is rotated with respect to the jaw 1 around the center 40 of the pin connection 19 (Fig. 8).

Underneath thefinger 39 is a transverse bight' 47 adjacent the extension 25. The bight 47 forms a recess for the reception and nesting of the coiled or looped portion of a spring 49 having one extension 51 of the coil or loop lying in a groove 53 in the central ear 13 of the jaw 1 and having another extension 55 from the loop located in a small hole in the finger 39. The force of the spring is exerted in a direction to bias the second jaw' 27 to move with respect to the first jaw 1, so that the stops 7 and 35 normally come together in closed position as shown in Fig. 1. This leaves the handle 17 freely movable relative to the first jaw 1 around center 40. Under these conditions, the space S between the outer ends of a the jaw 27 and the first jaw 1 is suflicient to pass around the sides of threaded cylinders C adapted to receive a standard nut N, so that if it might be required to approach the nut axially in order to apply the wrench,

this cylinder C will, if axially long, not interfere with The spring as shown Patented May 24, 1960 tensioned than the corner ofa V-shaped type of spring. The coiled helix type is therefore preferable because it will last longer. Moreover, it takes up less space, being positioned with the axis of the helix substantially parallel to the axes of pins 19 and 29.

Ordinarily the wrench is applied transversely from a side of a nut N, as illustrated in Fig. 6, wherein the straight dart 57 indicates the thrust applied to the handle 17. This thrust is such that the fingers 9 and 37 are wedged apart by two angular faces of the nut and ride over opposite parallel faces thereof. During this application the jaw 1 may rotate into rigid relationship with respect to the handle 17 (stops 21 being engaged), as suggested by the circular dart 59, indicating initial jaw 1 rotation about the center 40. During this action the second jaw 27 has oscillated on jaw 1 around center 30, as indicated by dart 61. Note in this connection that the bight 47 accommodates the looped portion of spring 49.

Fig. 7 shows conditions after completion of the thrust movement 57, wherein the surfaces 3, 5, 9 and 31, 33, 37 of the jaws 1 and 27 have snugly engaged the six sides of the hexagonal nut N. At this time the stops 7 and 35 are slightly separated and the jaw 27, under reaction from spring 49, has oscillated back from its position shown in Fig. 6, as suggested by the curved dart 63. The handle 17 (Fig. 7) is at this time free to swing around the assembly constituted by the jaws 1, 27 and nut N. Clockwise swinging movement is illustrated in Fig. 8, the dart 63 showing initial manual rotation of the handle 17 around the center 40. The rotation proceeds until the lug 43 engages the notch 41, whereupon the jaws 1 and 27 are locked on the nut N. Further manual turning pressure on the handle 17 will rotate the entire assembly of handle 17, jaws 1, 27 and nut N around the center 50, as indicated by the dart 65 in Fig. 8, thus rotating the nut to tighten it if it is of the right-hand thread variety.

After the nut has rotated an amount determined by the space available, pressure on the handle 17 is reversed in direction, resulting first in its freely turning on the center 40, as indicated by the dart 67 in Fig. 9. This action ends when the stops 21 engage and opens up the connection between the lug 43 and notch 41. Therefore, as the jaws 1 and 27 turn counterclockwise around the nut N, the rocker jaw 27 may rock or oscillate with respect to the jaw 1. At this time rotation is around center 50 (see dart 68). This occurs as the jaws ride over the corners of the nut N, as indicated by the doubleheaded dart 69 in Fig. 9. Stated otherwise, the oscillation occurs under the camming action of the corners of the nut on the surfaces 3, 5, 9, 31, 33, 37, the spring 49 biasing the ends of the jaws 1 and 27 against the sides and corners of the nut. After completion of the reverse movement through the angle available for the purpose, the handle 17 is again driven in the original direction (as in Fig. 8) for driving the nut further toward fastened position. When driving the nut as in Fig. 8, the grip on six sides thereof is strong thus avoiding slippage and scarification of its corners. Also, the reverse ratcheting action as in Fig. 9 occurs with only a light clamping action due to the spring 49, thus also avoiding said scarification.

In order to loosen a right-hand nut it is only necessary to turn over and apply the wrench, in which event the action above described will occur reversely, as is obvious from the description already given.

It should be noted that if in the condition of parts shown in Fig. l the handle 17 is rotated clockwise around center 40, the lug 43 will engage the inside portion of finger 39 adjacent notch 41, so as to prevent the lug 43 from advancing into crushing engagement with the spring 49. The dart 71 drawn around center 40 in Fig. 1 illustrates this point. Under these conditions the stops 7 and 35 are engaged.

In view of the above, it will be seen that the stops 21 comprise lost-motion means between the first jaw 1 and the handle 17, limiting relative handle motion in one direction, whereas the notched extension 39 and the lug 43 constitute lost-motion stop means between the second jaw and the handle, limiting handle motion in the reverse direction. It will be apparent that although a ratcheting action is obtained, no ratchet teeth or pawls are employed in the wrench. The three main parts 1, 17 and 27 of the wrench may be readily forged at low cost to provide a rugged three-piece construction requiring only the two auxiliary rivets 19 and 29 and the spring 49 to complete the assembly of parts required. Moreover, the assembly is simple, requiring only the proper application of the rivets 19, 29, and the spring 49. Additionally, the spring may readily be replaced should it break or lose its temper.

The distance between centers 30 and 40 is preferably greater than the distance between centers 30 and 50. Although this is not absolutely necessary, it is desirable in order to obtain a mechanical advantage between the action of the lug 43 on the jaw 27 relative to the clamping force between the ends of the jaws 1 and 27 on the nut N.

In view of the above, it will be seen that the several objects of the invention are achieved and other advantageous results attained.

As various changes could be made in the above con structions without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawing shall be interpreted as illustrative and not in a limiting sense.

I claim:

1. A wrench comprising'first and second jaws, a first single-centered pin connection between said jaws, a handle, a second single-centered pin connection between said first jaw and said handle, said jaws having nut-engaging surfaces adjacent their ends which are located on the side of said first pin connection opposite said second pin connection, a coiled helix type spring means having its axis substantially parallel to the axes of the pin connec' tions and having ends respectively seated on the jaws and reacting between the jaws exclusively of the handle and biasing said surfaces on the respective jaws for movement toward one another, first lost-motion stop means between the jaws limiting said jaw movement to jaw positions wherein said nut-engaging surfaces of the jaws are in closed positions, second lost-motion stop means limiting motion in one direction between the first jaw and the handle, and third lost-motion stop means limiting motion between the second jaw and said handle which is in a direction opposite to the motion of the second lostmotion stop means, said third lost-motion stop means comprising an extension from the second jaw and a lug on the handle, said extension forming a bight between the jaws, the coil of the helix of the spring means being located in the bight, and the ends of the spring means being respectively located in recesses in the jaws.

2. A wrench comprising first and second jaws, a first single-centered pin connection between said jaws, a handle, a second single-centered pin connection between said first jaw and said handle, said jaws having nut-engaging surfaces adjacent their ends which are located on the side of said first pin connection opposite said second pin connection, a spring member looped around an axis located substantially parallel to the axes of the pin connections and having ends which extend normally to said axis and which are respectively seated on the jaws and reacting between the jaws exclusively of the handle and biasing said surfaces on the respective jaws for movement toward one another, first lost-motion stop means between the jaws limiting said jaw movement to jaw positions wherein said nut-engaging surfaces of the jaws are in closed positions, second lost-motion stop means limiting motion in one direction between the first jaw and the handle, and third lost-motion stop means limiting motion between the second jaw and said handle which is in a direction opposite to the motion of the second lost-motion stop means, said third lost-motion stop means comprising an extension from the second jaw and contact means on the handle for contact by the extension, said extension 5 forming a bight between the jaws, the loop portion of the spring member being located in the bight, said ends of the spring member being respectively located in adjacent recesses in the jaws.

References Cited in the file of this patent UNITED STATES PATENTS Logan Jan. 9, 1951 Greer et a1 Apr. 22, 1952 Logan Nov. 25, 1952 Milentz June 30, 1953 Koenig Feb. 16, 1954

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