US2423326A - Pivoted jaw latch-grip pipe tongs - Google Patents

Description

July 1, 1947. o. v JONES 2,423,326

PIVOTED JAW LATCH-GRIP PIPE TONG Filed sept. 28, 1944 TOPO/EV 'atente'd .uly 1947 UNITED STATES PATENT (3F-FICEl PIVOTED JAW LATCH-GRIP PIPE TONGS Oscar V. Jones, Dallas,V Tex. Application September 28, 1944Sera1 No. 55.651,204

6 Claims.

This invention relates to tongs and it has particular reference to pipe and casing tongs.

The principal object of the invention is to provide a pipe and casing tongs having all of the prerequisites of conventional tongs butA possesses the added feature of a safety catch, whose novel function enables it to hold two jaws, constituting the work engaging elements in each of two positions, thereby providing for adjustment of the jaws to accommodate the same to pipe of different diameters. Manipulation of the safety catch, moreover, is effected at a position on the tongs calculated to reduce the hazard of injury to one making the adjustments which latter are reduced to a simple sliding action.

Another object of the invention is to provide a simplified tongs whose work engaging elements are so constructed and arranged as to impose upon the work an equalized and uniform pressure on all sides, and further, by virtue of a novel form of leverage, the jaws of the tongs are released for adjustment or for removal from the work instantly, by a simple, limited movement of the handle of the tongs.

With the foregoing objects as paramount, the invention has further reference to certain features of accomplishment which will become apparent as the description proceeds, taken in connection with the accompanying drawings where- Figure l is a plan View of a tongs constructed according to the present invention, with the handle broken away and showing the jaws expanded.

Figure 2 is a similar view, showing the jaws closed in two positions, the dotted lines illustrating the relative positions of the jaws, handle and lever when expanded to engage work of larger diameter.

Figure 3 is a view from underneath Figure 2.

Figure 4 is a fragmentary perspective view of the tongs to better illustrate the safety catch, and

Figure 5 is a fragmentary sectional view of the tongs handle, showing the safety catch in longitudinal cross-section.

Continuing with a more detailed description of the drawing, reference numeral I0 denotes a major work engaging jaw which is bifurcated at its free end to provide ears Il, betweenrwhi'ch operates a latching element I2, the latter being pivoted on a pin i3. Further reference to this element will be made presently.

The opposite end of the jaw ID has a bearing I4 which is embraced by ears I5 of a complementary minor work engaging jaw I6, which is pivot- 2. ally displaceable with respect to jaw Ill, on a pin I1. The bearing I4 of the major jaw is shaped to define a boss I8'- therebelow which serves as an anchorage for the bifurcated end I3 of a handle 20, the latter being shown partly broken away. The handle is pivotally mounted on a pin 2L.,

Refering again to the latching element I2; this member has a hook 22 which, in operative lposition, overlies and engages the free. end of the minor jaw I'G, in the manner shown in Figure 2. When the jaws are disposed to engage apipe of small diameter, the hook 22*r` engages the jaw [.6 behind a flat protuberance 23 near the endof this jaw but in the second position, that shownin broken lines in Figure 2, the hook 22 bears upon the` surface of this protuberance. In each case however, theV jaws are held against release by means of a safety catch 24, mounted rearwardly of the jaws, on the handle 20, and shown .in detail in Figures* 4 and 5 and which will be more particularly described presently. l

The latehing` element l2 is further provided with al shank or tail 25l which is pivoted on a pin 26 in the bifurcated end 211 of a link. 28,l lying below the jaw assembly as shown in the drawing, but in actual operation, this link is disposed at the side of the tongs, since the handle 2U is actuated on a horizontal plane. Y

The opposite end of th link 2B, which is also bifurcated, engages-,av boss 29 depending from the handle, in offset relation to the anchor pivot 2` thereof. Thus, it will be seen that asthe handle 20 is oscillated, the link 28 will transmit a similar movement to the shank 25 of the latching element l2, causing thehook 2.2' to move in relation to the free end ofthe minor jaw f5 when the latter is in collapsed position. In this manner, the jaws are latched upon and unlatched from a pipe. It is also apparent that the pressure imposed bythe latchon the jaw i6 is indirect proportion to that imposedon the handle 2U to rotate the pipe. Each jaw has a series`- of slip inserts 3U for gripping the pipe and.V these elements may be secured in any conventional manner.

Returning to the safety catch earlier referred to; this element consists ofthe body 24 which is disposed for. sliding movement longitudinally on the handle 20 and. to permit such movement, a slot 3|` isf made therein, through which extends a. pin 32. This pin'is anchored' in the handle Z0", as shown, and has ahead 33 thereon. A spring 34" surrounds the pin and bears upon the catch 24 to impose yielding pressure thereon to hold it in adjusted positions.

The catch 24 is further provided on one end with steps a and b (Figure When the body 24 is advanced towards the jaw assembly suiiicient distance to permit the step a to drop into a recess 35 of the handle end I9, the end of the catch constitutes a wedge between the wall of this recess and the boss I3 of the major jaw I0 which functions to limit the degree of relative displacement between this jaw and handle. This displacement is such that the jaws l0 and i6 may be expanded to the position shown in broken lines in Figure 2 which is the maximum displacement,

allowing the jaws to embrace a pipe of large diameter. To secure the jaws operatively on a pipe of smaller diameter, the catch 24 is moved so that the step b thereof will lie in the recess 35 of the handle further restricting the relative displacement of the handle and jaw Ill.` Thehook 22 of the latch will then lie behind the protuberance 23 of the major jaw I6, as shown in solid lines in Figure 2 which shows minimum contraction of the jaws to embrace a pipe of smaller cliameter. Until the catch 24 is manually moved rearwardly, the jaws cannot be released from the pipe. In each position of the jaws, it is obvious that a ratchet action can be eifected.

The catch 24 is held in adjusted positions by means of a projection 36, rising from the handle 20 and entering a longitudinal groove 3l in the underside of the catch 24 (Fig. 5). A pin 38 extends transversely through the catch 24 and the slot 31, and bears against the projection 36 while the catch is inoperative to prevent the latter from being accidentally moved to operative position. When it is required to so move the catch, the rear end thereof is lifted against the tension of spring 34 to dispose the pin 38 on the opposite side of the projection 36, in which position it prevents accidental movement of the catchto inoperative position.

It is obvious that there is no longitudinal pressure imposed on the catch when the latter is operatively disposed, hence the pin 38 is adequate to hold the catch in both positions. Moreover, in serving as it does to so hold the catch, it presents a safety feature inasmuch as it is impossible to displace the jaws of the tool from the work while the catch is in position.

Manifestly, the construction as shown and described is capable of some modification and such modiiication as may be construed to fall within the scope and meaning of the appended claims is also considered to be within the spirit and intent of the invention.

What is claimed is:

1. Pipe and casing tongs including :major and minor work engaging jaws pivoted together at their rear ends and free from connection at their forward ends, a handle pivoted to the major jaw, having a recess adjacent its pivotal point, a latchingmember pivoted intermediate its ends to the forward portion of said major jaw and having a tail and a hook adapted for adjustable engagement with the forward end of said minor jaw, a link connecting the tail of said latch to said handle to effect actuation thereof by said handle, a longitudinally slidable catch mounted on said handle having steps in one end, selectively receivable in the recess of said handle to restrict relative displacement of said major jaw and handle and means for guiding said catch.

2. Pipe and casing tongs including major and minor work engaging elements, having relative pivotal connection only at their rear ends, a handle pivoted to said major element, a latch pivoted intermediate its ends to the front of said major element and engageable in a plurality of positions with the front of said minor jaw to compensate for variations in diameter of the work, means to effect movement of said latch upon movement of said handle and means adjustable to positions equal in number to the operative positions of said latch to provide a wedging action between said handle and major jaw to limit relative displacement thereof.

3. Pipe and tongs including pivoted work engaging elements adapted to be collapsed about the work, a handle pivoted to one of said elements, a latch pivoted to the forward end of said major element, a link connected to said latch and actuated by said handle for securing said elements about the work in at least two positions and means carried by said handle and operatively providing a wedge between the back of oneV of said jaws and said handle to restrict displacement thereof to at least two positions to determine the degree of expansion of said work engaging elements under control of said latch.

4. Pipe tongs including a pair of jaws adapted to be collapsed about a pipe, a latch pivoted intermediate its ends to one of said jaws, for holding said jaws in latched relation to the work in at least two positions, a handle, means pivotally connecting said handle and latch for operating said latch and means adjustably mounted on said handle and movable into a recess in the end of the latter to bear against and hold the other of said jaws to restrict displacement thereof with said iirst jaw to at least two positions.

5. Pipe tongs including a pair of relatively pivoted jaws and a pivoted handle, a latch pivoted intermediate its ends to one jaw and engaging the other to hold said tongs on the work, means pivotally connecting said handle and latch, a catch slidably mounted on said handle and engageable in a recess between said handle and one of said jaws and effective to limit relative displacement thereof to correspondingly limit relative displacement of said jaws Vunder the control of said latch.

6. The structure as described in claim 5, further deiined in that the catch is comprised of a longitudinally slotted member having a stepped end and held under spring tension by a pin eX- tending through the slotI thereof, and means for constraining the body against lateral displacement.

' OSCAR V. JONES.

REFERENCES CITED The following references are of record in the iile ofthis patent:

-T.VH\TITED STATES PATENTS j Y Lundeen Feb. 9, 1943

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