US2060609A - Thread cutting device - Google Patents

Description

1936- M. J. CLABBY ET AL THREAD CUTTING DEVICE 3 Sheets-Sheet 1 Filed Oct. 21, 1935 INVENTORI' 1936- M. J. CLABBY ET AL THREAD CUTTING DEVICE Filed Oct. 21, 1953 s Sheets-Sheet 2 ATTORNEYS.

Nov. 10, 1936. M. J. CLABBY ET AL 2,060,609

THREAD CUTT I NG DEVICE Filed Oct. 21, 1953 3 Sheets-Sheet 3 INVENTORI' ATTORNEYS.

Patented Nov. 10, 1936 UNITED STATES A'iNT OFFICE THREAD CUTTING DEVICE Application October 21, 1933, Serial No. 694,610

Claims.

This invention relates to a new and improved thread-cutting device, for cutting a thread in a pipe or other article.

One of the objects of the invention is to provide a new and improved holder for the thread-cutting device so that the same can be easily and conveniently inserted into and removed from its holder.

Another object of the invention is to provide the device with an improved holder for the thread-cutting die or dies so that there will be a limited relative movement between said threadcutting device (or devices) and the holder.

Another object of the invention is to provide a holder for the thread-cutting device, in which the holder shall have a single movable part for holding or maintaining the thread-cutting device (or devices) in the holder.

Another object of the invention is to provide an improved ratchet-drive for said holder, so that the ratchet-drive can be conveniently and reliably adjusted in orderto drive the holder in the forward or in the reverse direction, and said ratchet drive can be adjusted so that it is rendered inoperative.

Another object of the invention is to provide the device with an improved adjustable guide for guiding the movement of said device upon the pipe or the like.

Another object of the invention is to provide a guide which consists of inner and outer shells which are relatively turnable, the inner shell having cam slots and the outer shell having concentric slots, the outer shell also having openings in which there are located the pivot pins of a plurality of cam members, said cam members being provided with additional pins or lugs which are located in said cam slots.

Other objects of my invention will be set forth in the following description and drawings which illustrate certain preferred embodiments thereof, it being understood that the above general statement of the objects of my invention is intended merely to generally explain the same and not to limit it in any manner.

Fig. 1 is a top plan view of the improved device, showing the thread-cutting device in its operative position.

Fig. 2 is a side elevation of Fig. 1.

Fig. 3 is a bottom plan view of the device shown in Fig. 1.

Fig. 4.- is a detail elevation, taken in the direction of the arrows of the line 4-4 of Fig. 1,

Fig. 5 illustrates another embodiment of the invention.

Fig. 6 is a side elevation of Fig. 5.

Fig. 7 is a plan view illustrating the ratchetdrive, the drive being shown in the inoperative position in this view.

Fig. 8 is a diagrammatic view showing one of 5 the ratchet-drive arms, in the operative position.

Fig. 9 is a view similar to Fig. 8 showing the other ratchet-drive arm in its operative position.

Fig. 10 is a detail plan view of the adjustable guide which forms part of the device. 10

Fig. 11 is a detail View illustrating the connection between the adjustable guide, and the holder for the thread-cutting device.

For convenience, the device may be described as being held in the horizontal position, although 15 it may be operated in any position.

Referring to Fig. 1, the device comprises a ratchet-drive having a hollow member I, into Whose end socket an operating member 2 can be inserted. The ratchet-drive member l is provided with a regulating member 3 which is provided with a pivot pin 4 and a finger hold 5. Stop pins 9 and 6a are provided, and the finger hold 5 abuts either one of said stop pins in the respective operative positions of the ratchetdrive. One of these positions corresponds to the forward movement of the ratchet-drive, and the other position corresponds to the reverse movement of the ratchet-drive.

In the position shown in Fig. 1, the ratchetdrive is inoperative so that the device can be quickly removed from the pipe or other article which has been threaded. The respective positions of the finger hold 5 are indicated by the lines I and 1a,.

The device is provided with a thread-cutting device and an improved adjustable guide for the pipe, rod, or other object which is to be threaded.

Referring to Fig. 4, the thread-cutting device has a holder 3, having a flange 9 which is provided with teeth In, having intermediate recesses H. The member I is provided with a suitable socket i2, which fits over the flange 9 of the holder 8. The holder 8 is provided with a shoulder it, against which an edge of said socket l2 abuts, when the device is assembled. When the device is assembled, the inner ends of the teeth H3 are substantially flush with the adjacent edge of the socket 12. The member I is therefore provided with a suitable bearing upon the holder 8, and

said member I can be turned to and fro upon said holder 8.

Referring to Fig. 7, the hollow member I is provided with a pair of arms l5 and I50, which are pivotally connected to said member I by means of a pivot pin IS. A tension spring H is connected to the operating arms [5 and 1511, so as to produce a scissor-like closing movement of said arms 15 and Hill.

As shown in Figs. 8 and 9, the pivot pin 4, which turns in unison with the member 3, is provided with a cam !3 which has a flat face 19. When said cam is held in the position shown in Fig. 7, the operating ends of the arms i5 and Mia are held spaced from the recesses l i so that the membar I can be turned without operating the holder 8. When the fiat face I9 is in the position shown in Fig. 8, the arm 15a is in the operative position and the arm I5 is in the inoperative position.

Referring to Fig. 8. when the cam i8 is in the position there shown, the member i can be turned in the counter-clockwise direction, and the arm 15a then slips over the teeth I9 so that the holder 3 remains idle. When the member i is turned in the clockwise direction, the arm lilo causes the simultaneous turning movement of the holder 8.

Referring to Fig. 9, when the cam 98 is in the position shown therein, the member I can be turned relative to the holder 8 in the clockwise direction, and the members and 8 turn in unison when the member I is turned in the counterclockwise direction.

Referring to the embodiment shown in Figs. 1, 2 and 4, the holder 8 is provided with upstanding lugs 29 and 29:1, having the top flanges 2i and 2 la and having equal and parallel and planar faces 22 and 22a, said faces 22 and 2212. being perpendicular to the bottom faces of the lips or flanges 2| and Zia.

Referring to Fig. 1 the holder is also provided with a lug 23, having a planar face. When the thread-cutting device or die D is placed upon the top of the holder 8, it may fit loosely in said holder 8. However, instead of having a relative movement between the die D and the holder 8, the die D may be held immovable relative to said holder 8.

A certain limited relative movement between the die D and the holder 8 is often desirable, in order to permit the die D to shift so as to be accurately centered with respect to the work. If there is relative lateral movement between the die D and the holder 8, said relative movement is limited in one direction by the upstanding planar face of the lip 23. Said relative movement in another lateral direction is also limited by the accurately ground planar faces 22 and 22a. Relative longitudinal movement is limited by the accurately ground planar faces provided at the bottoms of the lips 2| and 2 la. This longitudinal movement is in excess of the normal clearance which is provided in order to enable the die D to be slid into and out of the holder.

Referring to Figs. 1 and 4, the die D can be retained in the holder 8, while permitting relative movement between said die and said holder, by means of a retaining member 24, which is turnably connected to the adjacent face 25 of the holder 8, said face 25 being preferably planar. The retaining member 24 is provided with a knurled finger-hold 26. In the position shown in Fig. 4, the retaining member 24 is in the operative position, and its flat face 24a abuts a stop pin 21, so that a part of said retaining member 24 projects above that face of the holder 8, upon which the die D rests. When the member 25 is turned in the counter-clockwise direction, its fiat face is brought to the upper position, so that the die D can be either inserted or removed.

Any suitable retaining member or members, such as a set screw or screws, can be utilized for clamping the die D to the holder 8, in order to prevent relative movement between them. The retaining device specifically illustrated in Figs. 1 and 4 permits a limited relative movement of the die D with respect to the holder 8, in a direction perpendicular to the axis of said holder 8, and also in a direction parallel to said axis. If desired, the members 28 and 28a could be dimensioned so as to permit little or no relative movement of the die D relative to the holder 8, in a direction parallel to the axis of said holder, while permitting a relative movement in a direction perpendicular to said axis. Likewise the distance between the faces 22 and 22a may exceed the correspondingdimension of the die D, as shown in Fig. 4, so as to permit the die D to have a limited turning movement about the axis of the holder 8. The movement of the die D relative to the holder 8 can therefore be regulated in any desired manner, by suitably dimensioning the parts, and if desired, the die D can be held immovable in the holder 8.

Referring to Fig. 2, the top of the lug 23 is below the bottoms of the planar faces 22 and 22a. Hence the device can be accurately shaped by means of a suitable revolving mill of cylindrical shape. This mill can be passed through the holder 8 so as to grind the planar faces 22 and 22a, and to also accurately grind the bottom faces of the lips 25 and Zia. Assuming that the holder is held in the horizontal position shown in Fig. 2 and in Fig. 4, said revolving mill may be mounted upon a vertical shaft, and said vertical shaft may be moved in a horizontal direction, so that the mill can simultaneously shape the above mentioned faces, while permitting the bottom face of said cylindrical mill to clear the top of the lip 23. Any suitable milling or grinding tool can be used for this purpose.

While I have shown an integral thread-cutting device or die D, having a square shape, the device can be shaped so as to receive a die of triangular or any other desired shape and the invention also applies to a thread-cutting device made of a plurality of parts.

Referring to Fig. 5, this shows a modified provided with a flange 36, into which box-like holder So having a top box-like part which is part the die D is dropped by a tilting movement. The top of said holder 8a is provided with a lug 3|, and said lug has an overhanging flange, as shown in Fig. 6, in order to limit the vertical movement of the die D relative to the holder 8a Said lug also has a vertical planar face adjacent to the bottom planar face of said flange.

A retaining member 32 is turnably connected to the holder 8a and said retaining member 32 has a fiat face 3312, which abuts a stop pin 34. In the position shown in Fig. 5, the retaining member 32 prevents the removal of the die D. When said member 32 is turned in the counterclockwise direction, its flat face 33 is moved to a position which permits the removal of the die D. In the embodiment shown in Figs. 5 and 6, there may be the same limited relative movement or movements between the thread-cutting device and the holder, as in the embodiment previously described.

If desired, the member 32 can clamp the die D to the holder, and the holder can be dimensicned so as to tightly hold the die D.

The underside of the member I has an adjustable guide G connected thereto for the work piece which is to be threaded.

Referring to Fig. 7 and Fig. 11, the member 9 is provided with internally threaded holes 35, there being any desired number of such holes.

The guide G is provided with an outer shell 36, and an inner shell 31. The inner shell 31 is provided with holes 35a, which register with the holes 35, when the device is assembled.

Referring to Fig. 11, the walls of the holes 35a are provided with shoulders 38, against which the heads of the screws 39 abut, when said screws are turned to their final position. The shell 31 is provided with lugs 4| having internally threaded holes. The outer shell 36 is provided with concentric slots 42, and the shanks of screws 43 pass through said slots and engage the internally threaded openings of the lugs 4| The heads of the screws 43 are slightly spaced from the outer shell 36 in order to permit a limited gurmng movement of the shell 36, relative to shell The shell 36 is provided with cam members C and said cam members C are provided with pins 45 which move in cam slots 46, which are provided in said inner shell 31. Said cam members 0 are also provided with pivot pins 41, which pass through suitable openings which are provided in the outer shell 36.

Hence, when the outer shell is turned relative to the inner shell, said cam members C are turned about their pivot pins 41, so that they project more or less within the central openings which are provided in said shells. Said gripping cam members C slidably engage the pipe or other workpiece, so that the guide is made adjustable for difi'erent sizes of pipe or the like.

A set screw 46 has its shank passing through an internally threaded lug of the outer shell 36, in order to prevent any relative movement between the shells 36 and 31, after the cams C have been adjusted.

The above mentioned construction of the adjustable guide diminishes its bulk and minimizes any binding of the relatively turnable shells 36 and 31.

Referring to the ratchet-drive, the fiat face E9 of the cam i8 causes said cam to be reliably held in the positions shown in Fig. 7 and Fig. 8.

The invention is not necessarily limited to the mounting of the arms I 5 and lfia' upon a single pivot as the improved cam Hi can be utilized with arms which are mounted upon separate pivots.

Likewise, while a complete combined tool has been illustrated, in order to show the complete combination, it is obvious that the elements of said tool comprise valuable and independent subcombinations which can be used independently of the complete combination which has been illustrated.

Referring to Figs. 1, 4 and 5, the flange 30 is generally equivalent to the members 20 and 20a. and 23, in limiting the movement of the thread-cutting means in a lateral direction. The member 3| and the members 2| and 2Ia of Fig. 4 limit the movement of the thread-cutting means relative to the holder, in a direction parallel to the axis of the holder. In both said embodiments, said retaining means prevent the removal of the thread-cutting means, save along a predetermined line of movement, which includes the tilting movement which is required to withdraw the die D from the embodiment shown in Fig. 5. In both said embodiments there is a movable retaining member which prevents the removal of the thread-cutting means along said predetermined line.

When we refer to limiting the movement of the thread-cutting means relative to the holder, it is to be understood that we include the locking of the thread-cutting means within the holder, so as to prevent any relative movement between the holder and the thread-cutting means.

For example while we have shown a cam [8 having a flat face Hi, the invention is not limited to the use of a flat face, as we could use a mutilated face which may be convex, and even slightly concave.

It is preferable to have the mutilated face of the cam correspond in contour to the adjacent portions of the ratchet-drive arms.

Referring to Figs. 3, 6 and 10, the shanks of the screws 43 may be provided with shoulders, so, as to limit the entrance of said shanks, into the lugs 4|. These shoulders positively cause the heads of said screws to be spaced from the outer shell 36, thus preventing any binding between the shells 31 and 36. The shoulders of said screws 43 can abut the adjacent lateral faces of the lugs 4|. We have shown a preferred embodiment of our invention, but it is clear that numerous changes and omissions can be made without departing from its spirit.

We claim:

1. In a thread-cutting device, a holder adapted to have thread-cutting means located therein, said holder having a pair of upstanding lugs having lips which overlie and are spaced from said thread-cutting means, said holder also having a third lug intermediate the first mentioned lugs, said first mentioned lugs having upstanding ground faces and said lips having bottom ground faces, the bottoms of said upstanding ground faces being above the top of the third lug, the thread-cutting device having faces which correspond to and which are spaced from the adjacent faces of said three lugs, said holder having a holding device which is adapted to retain said thread-cutting means loosely in position between said lugs, said holding device being spaced from said thread-cutting means when the holding device is in operative position, the holder having teeth adapted to be engaged by the pawls of a ratchet-operating device.

2. A thread-cutting device comprising a holder, thread-cutting means movable into and out of said holder, retaining means adapted to retain said thread-cutting means in said holder, while permitting a limited relative movement between said thread-cutting means and said holder in a direction perpendicular to the axis of said threadcutting means, and movable holding means adapted to prevent the removal of said threadcutting means from said holder, said movable holding means being spaced from the thread-cutting means when said holding means are in the operative position, so as to permit said relative movement of the thread-cutting means, the clearance between said thread-cutting means and said retaining means being in excess of the clear ance which is required to insert and to withdraw said thread-cutting means, said holder having teeth adapted to be engaged by the pawls of a ratchet-operating device.

3. In a thread-cutting device, a holder having teeth adapted to be engaged by the pawls of a ratchet-operating device, said holder having a plurality of upstanding lugs between which a thread-cutting device can be located, a movable holding device connected to said holder and adapted to retain said thread-cutting device between said lugs, said holding device being spaced from the thread-cutting device when the holding device is in the operative position, said threadcutting device being movable relative to the holder in a direction perpendicular to the axis of the holder, the clearance between said thread-cutting device and said lugs being greater than the normal clearance which is required to insert said thread-cutting device in position.

4. In a thread-cutting device, a hollow ratchetdrive member having a socket into which the toothed end of a holder for a thread-cutting device can be fitted, said member having a pair of pivoted arms connected thereto, spring means adapted to force the ends of said arms into engagement with the teeth of said toothed end, said member having a turnable cam located between said arms, said cam having flat face, both arms contacting with said cam in all positions of said cam, each arm being in the operative position when it contacts with the flat face of said cam, both arms being held in the inoperative position when neither arm contacts with the fiat face of the cam.

5. A thread-cutting device comprising a holder having teeth which are adapted to be engaged by the pawls of a ratchet-operating device, said holder having a pair of upstanding lugs which are provided with parallel planar faces which are parallel to the axis of the holder, said lugs having inwardly extending lips at their tops, the top of said holder having a third lug which is located between the previously-mentioned lugs, said third lug having an inner planar face which is parallel to said axis and which is perpendicular to the planar faces of the previously mentioned lugs, a thread-cutting device having an outer periphery of rectangular cross-section and slidable into position so that three of the faces of said holder are adjacent the planar faces of said three lugs, and a movable holding device adapted to retain said thread-cutting device in position between said lugs, said holding device being spaced from said thread-cutting device when the holding device is in operative position, said thread-cutting device being movable relative to said lugs in a direction perpendicular to the axis of the holder, the clearance between the threadcutting device and said lugs being greater than the normal clearance which is required for permitting the holder to be inserted into position between the lugs.

HARRY S. ASHMUN. MICHAEL J CLABBY.

Images