US1252630A

US1252630A - Screw threader and pointer.

Info

Publication number: US1252630A
Application number: US19262617A
Authority: US
Inventors: Fred Newell Tilton
Original assignee: Individual
Current assignee: Individual
Priority date: 1917-09-21
Filing date: 1917-09-21
Publication date: 1918-01-08
Anticipated expiration: 1935-01-08

Description

F. N. TIL-TON.

SCREW THREADER AND POINTER. APPLICATION FILED AUG-1,1914. RENEWED SEPT.2I, I917.

'5, 252, 6 3 o Patented Jan. 8 1918.

F. N. TILTON.

SCREW THREADER AND POINTER.

APPLICATION r1151) AUG-1. 1914. RENEWED sPT.21, 1911.

Patented Jan. 8, 1918.

6 SHEETS-SHEET 2.

52:11.4. 7/, PM Mfa/LW F. N. TiLTON.

SCREW THREADER'AND POINTER. APPLICATION FILED AUG- 1. mm.

RENEWED SEPT. 21, I917.

Patented Jan. 8, 1918.

6 SHEETS-SHEET 3.

x lad 42': 7

F. N. TlLTON.

SCREW THREADER AND POINTER.

APPLICATION FILED AUG-H1914. RENEWED SEPLZI, 1917.

Patented Jan. 8, 1918.

6 SHEETS-SHEET 4| .F. N. TILTON. SCREW THREADER AND POINTER. APPLICATION FILED-AUG. 1. 1914. RENEWED SEPLZI, 19:7.

1,252,63Q; Patented Jan; 8, 1.918.

s SHEETSSHEET 5.

F. N. TILTON.

SCREW THREADER'AND POINTER. APPLICATION FILED AUG- 1. 1914. RENEWED SEPT.2I, 1911.-

Patented Jan. 8, 1918.

6 SHEETSSHEET 6- STATES PATENT @FFICE.

ZIE IBJEII) NEWELL TILTON, F HARTFORD, CONNECTICUT.

' SCREW THREADER AND POINTER.

Specification of Letters Patent.

Fat-tented J an. 8, 1918.

i Applicationfilegi August 1,191 Serial No. 854,513. ,Renewed september 21, 1917. Serial No. 192,628.

To all whom it may concern:

-Beit known that I, FRED N. TILT N, a -citizen, oftheUnited States, residing at -,Hartf0rd in the county of Hartfordand State of Connecticut, have invented anew ,and useful Improvement. in Screw Threaders and Pointers, of which the following is a specification.

This invention relates to the mechanism 111 a screw form ng machine whlch controls the operation of the tool for cutting the jthreads upon the blanks. As the invention is particularly applicable to the mechanism which affects the movements of the tool for threading and pointing gimletpointed wood screws it is illustrated and described herein as embodied in a wood screw machine.

In machines for threading and pointing gimlet-pointed wood screws the blanks are fed one at a time to a guide and driver and while rotated by the driver are subjected to the action of a tool which is so fed as to cut the required threads, This tool is repeatedly fed along the blank from the shank to the point and returned, each time making a pendsuponthelength of the screw a form or depth cutting cam which through the ,form plate increases the depth of each cut until the thread. is completed; a return cam which acts, so. that the tool will be drawn away from the blank during its return move- ,mentpand a holder cam which acts so as to allow the tool to be held out while the blanks A, are being fed into the guide and engaged by the driver which causes their rotation;

all of these parts being combined with the ,necessary actuating and connecting mechanisms which cause them to automatically control the movements of the cuttingtool to effect-the desired result.

II he object .of this invention is to provide a machine of this character with means whereby the tool, at each successive advance during every cycle of the machine, as it an proaches the tips of the blanks will not only cut deeper. but will be carried in toward the y axes of theblanks so as to form the necessary gimlet points at the ends of the screws, thus obviating thenecessity-of previously pointing the blanks in another machine as has her tQfQ ae n. see idere ls ia o the successful production of high-grade wood screws. i

This object is attained in a preferred manner by providing a pointing cam, and the necessary connections, which will slowly feed the controlling form in such manner that the tool each time it approaches the end of a blank not only makes a deeper cut for forming the thread but moves in so as to point the blank and form the desired thread on the pointed end.

As the blank feeding, rotating, guiding. and re easing mechanisms form no part of the present invention, and may be any of the types in common use, they are not illustrated'and described herein, only so much of a wood screw machine being set forth as is necessary to a complete comprehension of the preferred embodiment of the invention. Flgure 1 shows a front elevation of shows a side elevation of the form,,the form or depth cam which causes-the tool to cut deeper at each successive feed, the holder am which allows the tool to be held out when the blanks are being fed into cutting position, and the levers which provide the connections between these cams and the form. Fig. 7 is a section through the tool post on the plane indicated by the dotted 'line 77 on Fig. 1, showing a side elevation of the tool and its carrier, the tool post arm and part of the form plate and arm. Fig. 8 I shows a plan of the form with one of the form plates used for controlling the action of the tool. Fig. 9 shows a side View of the return cam, the form and the lever which connects these parts. Fig. 10 shows a plan of the form and the lever attached to the form arbor which is actuated. by the depth cam and holder cam.

The cutting tool 1 is adjustably fastened in a carrier 2 that is clamped on atool post 3. This post is loosely supported so that it may be turned and also moved longitudinally in bearings in thestandards 4t and 5 hi h. extend ner l r fli s? t e b d f the tool actuating mechanism of the ma-' the machine illustrated. The tool post is 10. "post. The spring is fastened between moved in one direction for feeding thetool along from the shank to the point of the screw 7, by the lead cam 8 that is adjustably fastened to the front cam shaft 9, and the post is drawn in the opposite direction by the spring 10 which has one end fastened to the. standard 11, that extends upwardly from the bed, and which has its otherend fastened .to an arm 12 that is clamped to the these parts so that it not only holds the post back against the lead cam but tends to draw the arm in and turn the end of the cutting tool out from the screw blank. The lead cam is shaped and timed to advance the tool at such a speed that it will cut a thread of the desired pitch on the screw blank.

Clamped on the tool post is an arm 13. The lower and inner end of this arm is held against the form plate 14 by the pull of the spring 10 which draws back the tool post. This form platevaries in size and shape according to the size and shape of the screw which is to be formed and its front edge is curved forwardly at one end so that as the tool post is moved by the cam for causing the tool to cut, the arm 13 near the end of its movement is forced out and the tool is turned in toward the axis of the blank forforming the point of the screw. The form plate is attached to an arm 15 which is clamped to the form arbor 16 that in the machine illustrated is loosely mounted in bearings in the standards 4, 5 and 11;

Clamped on the form arbor is a rearwardly extending lever 17. This lever bears a spring finger '18 with a plate 19 which is adjusted to the desired position by a screw 20. The plate 19 is held in contact with the depth cam 21 by the pull of'a spring 22. The cam 21 is fastened on the back cam shaft 23. This cam is so shaped that through the lever 17 the arbor is turned and the form is swung in such manner that dur- "ing every cycle of the machine, at each advance the tool will make a deeper cut in the blank. F astened on the side of the depth cam 21 is the holder cam 24. This cam is adapted to engage the block 25, which is on one side of the lever 17, and hold the lever down with the form swung back so that the tool will be thrown out while during the operation of the machine ablank is, by any common feed mechanism, delivered into cutting position in the back guide 26 and is engaged by the driver 27 by means of which the blank is rotated, in the usual way in machines of this type.

'Adjustably fastened on the front cam. shaft 9 is the cam 28 which is adapted to engage the return cam lever 29 that is fastened to the form arbor 16. This cam is so timed that it rocks the lever, turns the arbor and swings back the form so as to allow the tool to swing out away from the blank each 3 time it makes its return movement.

On the back cam shaft 23 is a cam 30 engaging with the face of which is the end of longitudinally and carries the form side-- wlse so that at each-successive advance of the tool the form arm 13 travels a little farther up on the curved end of the form plate.

As a result of this the tool not only at each advance makes a deeper cut but at the end of each advance is caused to cut away the tip of the blank so as to form the desired point of the screw. 9

Power for rotating the shafts and cams is applied to the driving pulley 35 which is on one end of the drive shaft 36 that extends across the machine and at the other end has a drive'pinion 37. The drive pinion meshes with an intermediate gear 38 which with its attached pinion 39 is mounted on a bracket40 that is adjustably fastened to the outer face of the standard 11. The pinion 39 engages with the gear 41 that is fastened on the front cam shaft 9. Attached to this gear is a pinion 42 which meshes with a sec ond intermediate gear 43 that with its attached pinion 44 is mounted on a bracket'45 that is adjustably fastened to the outer face of the standard 11. The pinion 44 engages with a gear 46 that is fastened to the end of the back cam shaft 23. 7

By means'of the addition to'the screw machines in common use of the simple pointing cam and lever for moving the form arbor as above described, the form, which controls the depth at which the tool cuts into the blank,--which permits the tool to return freely after each cut,and which permits the tool to be held out while the a spring for returning the tool, a form for controlling the movements of the tool, a

depth cam actuating the form so as to 'regulate thedepth of the tool cut, a pointing cam actuatmg the form so as to cause the tool to point the blank, and a return cam actuating the form so as to allow the tool to withdraw from the blank when it is returned.

2. The combination in a screw machine of a tool, a lead cam for advancing the tool, a spring for returning the tool, a form for controlling the movements of the tool, a cam actuating the form for regulating the depth of the tool cut, a cam actuating the form for causing the tool to cut the point of the blank, a cam actuating the form for causing the tool to be Withdrawn from the blank during its return movement, and a cam actuating the form for holding the tool out While the blank is being located in position to be cut.

3. The combination in a screw machine of a tool, a cam for advancing the tool, an oscillatory and reciprocatory form for controlling the position of the point of the tool, a cam for swinging the form so that each successive cut of the tool Will be deeper than the preceding cut, and a cam for feeding the form longitudinally so that near the end of each advance the tool will cut deeper than at the same locality during the preceding cut for threading and pointing a screw.

4. The combination in a screw machine of a tool, a lead cam for advancing the tool, a spring for returning the tool and holding it away from the blank, an oscillatory and reciprocatory form for turning the point of the tool toward the blank, a cam for swinging the form so as to increase the depth of the successive cuts, and a cam for reciprocating the form so as to still more increase the depth of the successive cuts near the end of each advance movement of the tool.

5. The combination in a screw machine of a tool, a form for controlling the cutting action of the tool, and two independent cams arranged to actuate the form, one of said cams feeding the form transversely so as to regularly increase the depth of each tool cut, and the other of said cams feeding the form longitudinally so as to still further increase the depth of each tool cut near the point of the blank.

6. The combination in a screw machine, of an oscillatory and reciprocatory form, a spring cam and lever for oscillating the form, and a spring, cam and lever for reciprocating the form.

7. The combination in a screw machine of an oscillatory and reciprocatory form, means for oscillating the form, and means for reciprocating the form, said form oscillating and form reciprocating means being separate and acting independently of each other.

FRED NEWELL TILTON.

W'itnesses:

J AMES F. STOREY, Gnaon GAULT.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

Washington, D. C."