US3177507A - Bolt pointer - Google Patents

Description

April 1965 P. D. BECKER ETAL 3,177,507

I BOLT POINTER Filed May 24, 1962 3 Sheets-Sheet 1 'PHILLIP D. BECKER ROBERT M. RIGOT Y/QQZMAZW AT TOBN EYS A ril 13, 1965 P. D. BECKER ETAL 3,177,507

BOLT POINTER Filed May 24, 1962 3 Sheets-Sheet 2 INVENTOR I50 PHILLIP D. BECKER BYROBERT M. RlGOT "z,g"5

ATTORNEYS April 13, 1965 Filed May 24, 1962 P. D. BECKER ETAL 3,177,507

BOLT POINTER 3 Sheets-Sheet 3 25 210 i/zso 252 INVENTOR PHILLIP D. BECKER ROBE-RT M. RIGOT ATTORNEYS United States Patent 3,177,507 BOLT POINTER Philip D. Becker, Woodhury, and Robert M. Rigot, Cheshire, Comm, assignors to Buell Industries, Inc., Waterbury, Comm, a corporation of Delaware Filed May 24, 1962, Ser. No. 197,386 11 Claims. (Cl. 10-21) This invention relates to machine tools for pointing operations, and more particularly to machines for chamfering or pointing bolts, screws and similar fastening devices.

In the manufacture of bolts and screws, wire or rod stock of suitable metal is fed to a bolt making machine which first forms the head of the bolt, etc., by upsetting the metal stock, after which a selected length, of the stock is sheared or severed to provide a headed blank of desired length. Generally the shanks of these blanks are thereafter threaded by thread rolling or chasing operations but before these operations can be performed, the blanks must be chamfered at their distal ends to eliminate the formation of a burr or weakened starting thread which would otherwise be produced. This chamfering operation is commonly referred to as pointing and has been accomplished heretofore in various ways, as shown for example in an early patent, No. 679,540 and more recently in No. 2,448,305. However this pointing operation has long been a source of trouble, giving rise :to production problems in bolt and screw manufacture. These problems have been occasioned in large measure by the relatively low production capacity of the available apparatus and methods of pointing the blanks. Tool chatter and resulting excessive tool wear and breakage, as well as roughened surfaces of the work, are some of the more common difliculties. In fact, the pointing operation has until now been a principal bottleneck in the manufacture of threaded bolts and screws, as the capacity of bolt-forming machines now available greatly exceeds that of the means for pointing the blanks.

It is accordingly an object of this invention to provide improved apparatus for pointing bolt, screw and similar fastening devices. The improvements afforded by the invention include not only a very substantial increase in the speed at which individual bolts, etc. may be pointed, but a greater flexibility and capability of pointing apparatus to handle different types of pointing operations on different types of metals with little or no change in the apparatus.

To this end, the apparatus herein disclosed is characterized by relatively simple yet rugged construction, free ,of operating difiiculties. It is further characterized by freedom from objectionable chatter and vibration during chamfering of the Work blanks, thus producing smoother and more uniform points on the work. The design and construction of the apparatus is such as to provide large bearing surfaces at critical'load points, yet bulkiness and complexity of the unit are avoided.

In addition to compactness of the apparatus, which also makes for greater accessibility to and simplification in the means for feeding the bolt blanks automatically to the pointer, the invention further provides a unit which is essentially self-cleaning in that chips or shavings produced in the course of pointing the blanks tend to be thrown free of the work and of the machine. Clogging of the apparatus and its cutting surfaces, and unnecessary wear and dulling of those surfaces, is thus reduced.

The novel design herein disclosed further provides considerable excess available cutting surface beyond that needed at any one time, whereby simple adjustment may be made to shift the cutter or cutters of the apparatus to bring fresh cutting surfaces into use, without necessitating the removal of the cutters from the apparatus. This 3,177,507 Fatented Apr. 13, 1965 ice greatly reduces the down-time of the apparatus and consequently increases the production rate of which it is capable. In place of the usual cutting bit used in the standard box-pointers generally employed in the bolt making industry today, the novel apparatus makes use to good advantage of standard milling machine cutters of conventional design.

Greater ability to adapt the apparatus for cutting stock of different metals and consequently of different machin ing characteristics, is also provided by means of a coaxial spindle arrangement in the machines here disclosed, whereby the cutting speed of the apparatus can be varied at will to suit the particular work involved. Such arrangement also contributes materially to the compactness of the unit.

These and other advantages of the apparatus will become more apparent from the description which follows of several forms of pointing apparatus embodying the invention, as illustrated in the accompanying drawings.

In the drawings,

FIG. 1 is a plan view of a bench or work station at which a bolt pointing unit is positioned, showing means also for feeding the bolts automatically to the pointing head and extracting them after the pointing operation is completed;

FIG. 2 is a view in side elevation and on an enlarged scale of the bolt pointing head incorporated in the apparatus shown in FIG. 1;

FIG. 3 is an end elevational view of the unit shown in FIG. 2;

FIG. 4 is a sectional view of the head seen in FIG. 2, showing a bolt chucking arrangement and a bolt in position to be pointed in the head;

FIG. 5 is a sectional view, similar to FIG. 4, of a modified form of unit employing two beveled milling cutters in place of a single cylindrical cutter as shown in FIGS. 2 and 3;

FIG. 6 is a sectional view also similar to FIGS. 4 and 5 of still another modification; and

FIG. 7 is an end elevational view of the unit of FIG. 6.

In the plan view of a bolt pointing station illustrated in FIG. 1, a pointing head 10 is suitably supported on work surface or bench 12 by suitable frame members 14, 15, provided with bearings 16, 18, for receiving and journaling a spindle to which the bolt pointing head is secured at the forward free end thereof. I

Vibratory or other suitable bolt sorting and aligning means 22 is mounted on bench 12, and the bolt blanks are dumped into the hopper of this unit for delivery to the pointer. This sorting unit forms no part of the present invention and since various units for this purpose are commercially available, no detailed description of this unit is necessary. Suffice it to say that the oriented bolt blanks b are fed by gravity in side-by-side arrangement transversely of their length from sorter 22 along a track 24 to a pointing station which is depicted in FIG. 1 by the bolt B in axial alignment with pointing head 10. A conventional tucker 25 at this location separates the leading bolt from those following and its head is engaged to prevent the bolt from turning. Feed track 24 is pivoted at 27 adjacent sorter 22 and the entire track together with bolt B swings to permit introduction of the distal end of the bolt into the pointing head, as shown more particularly in FIG. 4. Pivoting of track 24 occurs with engagement of the head of bolt B by an anvil 26 carried by plunger 28 of a penumatic actuator 30. When the pointing operation is completed, plunger 28 is retracted together with track 24 and bolt B by a return spring 32 to the position shown in FIG. 1. This position is adjustable by means of set screw 33 against which track 24 normally comes to rest under the urging of spring 32. The tucker at the pointing station is then operated to r. 3 I r eject bolt B onto the adjacent surface of bench 12, and to advance the next bolt into position for'pointing. The pointed bolts pass downwardly through chute 34 to a tote box or similar container.

As here shown, aportionof frame 15 extends forwa'rdly of pointer and fonmsa guard fence 36 across the'face of the machine. at 38 to permit introduction of bolt B into the pointing head but serves to prevent accessof the bolt to the machine if not properly aligned therewith.

Details of pointing head 10 are illustrated more particularly in FIGS. '2, 3 and 4. As best'seen in FIG. 4, head 10 is secured by bolts 42 passing througha flange 40 formed at theforw'ard end of a spindle 20, and the pointing head is thus supported and rotated about an axis coinciding-with that of bolt B. Pointing head .10 as 'here shown comprises an integral casting or forging having a generally frusto-conical forward portion 44 with' the nose immediately adjacent the work being of-relatively small diameter, thus facilitating access to-the unit at the work-receiving end. Head 10 also has an integral cylindrical hub 46 of reduced diameter projecting rearwardly from the base of the frusto-conical portion.

The fence is suitably apertured 7 FIGS. 3 and 4, which cooperates with counterbore 48 to provide "clearance for milling cutter 52. digs having different sized aperturesare employed to fit bolts, screws,

" etc; of different diameters.

Referring again to FIG. '1, driving power is imparted to coaxial shafts and 78 by sheaves 100, 102, respectively, Sheave -100 has a large hub I04 enclosing ,a

bearing assembly .to support inner shaft 78 adjacent its the bolts, when engaged, to be drawn into the. machine.

The head is bored to provide concentric stepped bores 48, 50, inclining inwardly of the axis of rotation forwardly of the unit, for the reception of a. milling cutter 52 and supporting countershaft'54, more fully described presently. In the apparatus illustrated in FIGS. 2 through 4, the axis of bores 48, 50, intersects and crosses the axis of head 10 in the nose or forward portion 44 thereof. I i

This nose portion 44 is also milled or out along an axial plane to provide a slot 56 (see FIG. 3) extending partially through the diameter of the head and intersecting bores 48, 50.1 Double forward bearings 58, 58, are seated in bore 50 and are held in position against shoulder 49 by a clamping bolt 60 passing through the slotted portion adjacent the "bearings. A rear'bearing 62 is seated with a light friction fit in the rear of bore 50, and this together with'bearings 58 rotatably support countershaft 54.

Actually this cou'ntershaft as, here shown takesthe form of a'chuck sleeve having a forward peripheral flange 64 and is threaded, asat ,66, at its rearfor reception of a retaining nut 68. A conventional split collet 70 and collet tightening means 72 (see FIG. 4) are carried by the sleeve at its forward and rear ends, respectively, and the shank of milling cutter 52 is received and retained in the split collet in well-known manner.

Countershaft or sleeve 54 also has, adjacent its rear end, a bevel gear 74 which is splined or keyed to the This provides a substantially self-feeding arrangement after the bolts, screws, etc. have been brought into initial contact ,With' the cutter.

'A modified pointing head no employing dual milling cutters is shown in 'FIG. 5 This unit'is basically similar to'unit 10 describedaboveexcept for the use of two beveled milling cutters in placeof a single cylindrical cutter. Head 110 of the modification is secured by bolts 142 to flange 140' of outer spindle 120. .As before, head 110 comprises a one-piece casting or forging bored longitudinally at diametrically .opposed locations to provide inclined apertures 148 for the reception of collet sleeves 154. Paired cou'nterboredrecesses 150 are provided for seating bearings I58 adjacent each.end of sleeves 154.

The'axes of bores 148 are inclined forwardly and inwardly toward the nose of the pointer in intersecting relation with a the axis o'f the latter, but in this instance the axes do not cross the axis of rotation within the body of theunit. As

sleeve and held in abutment against a rearwardly facing shoulder (not shown) of the sleeve by retaining nut 68. Gear 74 is thus rotatablysupported in meshing engagement with a complementary beveled gear 76 which is, in turn, splined or otherwise secured to a spindle 78 telescopingly received within outer spindle 20 of the device. Support-for the forward endof spindle. 78 is supplied by a bearing assembly 80 received in a forwardly .facing recess 82 in the flanged end 40 of outer spindle 20, and

spindle 78 is substantially coterminal with the latter at such end. The hub portion 46 of pointing head'10is head by suitable screw means 92, as best seen in FIGS.

3 and 4. Jig 90 is provided with a central bore 94'extending partially through the jig and concentric with the axis of head 10. Theinner end of'bore 94 terminates in a conical seat 96 'whose conical angle conforms with that to be provided on the end of bolt B; Jig 90 also has a portion 98 of its'peripherymilled out, as seen in splined or'otherwise attached at .oneend. Both of gears 174 are in meshing engagement at diametrically opposite points with driving pinion 176. The latter is secured to the inner end ofspindle 178 which, in turn, is supported internally of spindle for rotation independently thereof-by a bearing assembly 180 seated in a'recess 182 of flange 140. Colletsleeves 154 each. incorporate a split collet or similar arrangement (not shown) forchucking a beveled millingcutter 152.. For conveniencein axially shifting or for changing cutters 152, the chucking arrangement is controlled at the cutterrend Ofzthfl spindle, rather than at the opposite end as in the former example.

Asgseen in FIG. 5, .the adjacent cutting" surfaces of millers 152 form an included angle which 'is bisected by the axisof rotation of head -11 '0.- Jig 190 is removably secured tothe; face or nose of-the unit and is provided with an. aperture 194.-located on the axis of rotation within'which the ends of the bolt'blanks are received. As .before,.a guard :fence.136 having an aperture 138 in alignment with thelaperture of jig 190 is supported closely adjacent the forward face of the unit. a

"I'lie operationofthis modified form of apparatusis identical with the earlier form described. Again it is desirable in this rnodification to employ milling cutters having helically inclined teeth with the helical inclination so directed as to cause the bolts, screws, etc. to bedrawn into the pointing headfafter'initial contact of the end of the bolt with the cutters has been made. I

A third variant within the invention is shown in FIGS.

, 6 and 7. In this unit two cutters are again employed as in the previous'example but. in this instance the axes of these cutters areskewed with respect to the central axis of the'pointer itself as'wellas' to .each other. This arrangement, as in the case of the first construction. de-

. scribed, permits the'use of plain cylindrical milling cutters.

I Referring to FIG. 6, pointing head '210 is secured by bolts 242 passing-throughflange 240 on spindle 220; Head 210 is bored to provide skewed passages 248 having recessed bearing seats 250 at each end of each such passage. As before, the inclination of the axes of bores 248 is inwardly towards the forward end or nose of pointer head 210, and in this case the axes again cross over the axis of rotation within the head itself. Spindles 254 are supported in these passages by bearings 258, and are driven by bevel gears 274 secured thereto. Plain sleeve bearings are illustrated in this embodiment and necessary lubrication is supplied through the use of a hollow inner spindle 278 and the provision of lubrication ducts 285 communicating each of bearings 258 with a central manifold 237 in the unit. Gears 274 mesh at diametrically opposite locations with pinion 276 which is fast with inner spindle 278. Collet or other suitable means for chucking cutters 252 are provided in spindles 254. A jig 290 fastened to the forward end face is provided with a central aperture 294 for the reception of the bolts and screws, and is secured by means of screws 292 to the head of the pointer.

Operation of this form of the invention is the same as in the case of the other modifications already discussed.

The pointing units illustrated in FIGS. 2 through 4 and 6, 7 have the advantage that milling cutters 52 and 252, respectively, may be am'ally shifted to bring a new portion of the cutting surface into operation, thus obviating the necessity of removing the cutter for resharpening. This effects a saving through reduction of down-time for the unit. The first mentioned unit also has practical advantages resulting from the use of collet spindle bearings which are substantially larger in diameter than the milling cutter, thus making for low unit stress on the more critical bearings in the unit. The use of dual cutters, as in FIGS. 5, 6 and 7, however, obviously provides greater cutting surface in contact with the work at any given time and consequently reduces the cutting time required for each individual piece.

Various other specific changes in construction of the apparatus may obviously be made and it is to be understood therefore that such modifications as properly fall within the scope and spirit of the following claims are intended to be comprehended thereby.

What is claimed is:

1. In apparatus for pointing the ends of bolts, screws and the like, a supporting frame, substantially coterminal, coaxially telescoping inner and outer driving spindles journaled for rotation on said frame, means for driving said spindles independently of each other in the same direction of rotation but at different speeds, a head secured to one of said spindles entirely forwardly thereof for rotation thereby, a countershaft journaled for rotation in said head, said countershaft being inclined inwardly toward the free end of said head, a driving member secured to said countershaft and a complementary driving member fast with the other of said spindles, said members being interconnected for driving engagement, a rotary cutter carried by said countershaft at its forward end and providing a cutting surface disposed at an acute angle to the axis of rotation of said head, and a jig mounted at said forward end portion having an axially disposed aperture for sliding reception therein of bolt and screw blanks to guide the inner ends thereof into contact with said cutter.

2. In apparatus for pointing the ends of bolt and screw blanks, a supporting frame, substantially coterminal, coaxially telescoping inner and outer spindles journaled on said frame, means for driving said spindles independently of each other, in the same direction of rotation but at different speeds, at head secured to said outer spindle entirely forwardly thereof, a countershaft carried by said head for rotation therein, said countershaft being inclined inwardly and forwardly of said head toward intersection with the axis thereof, gear means secured to the rear of said countershaft and a pinion secured to said inner spindle in mesh with said first gear, a milling cutter car-- ried by said countershaft adjacent the forward end of said head and having milling teeth forming an acute angle with the axis of said head, a jig removably secured at the forward end of said head and having an axial aperture for the sliding reception therein of bolt and screw blanks to guide the ends thereof into contact with said milling cutter.

3. Apparatus as defined in claim 2, wherein said head has a generally frusto-conical forward portion whose outer surface is substantially parallel to said countershaft to dispose the smaller diameter of said head forward.

4. Apparatus as defined in claim 3, wherein said frustoconical portion is slotted along an axial plane partially through said head, bearing assemblies received in said inclined bore for rotatably supporting said countershaft, and a clamping bolt passing through said head transversely of said slotted portion to permit clamping said bearing assembly within said bore.

5. Apparatus as defined in claim 2, wherein said head has a rearwardly extending cylindrical hub portion, and said outer spindle has a peripheral flange, screw means passing through the flange into said hub to secure said head to said spindle.

6. Apparatus for pointing the ends of bolts, screws and the like, which comprises a pointing head and a hollow spindle having an external flange at one end, means rotatably supporting said hollow spindle and means for removably securing said head to said flange to support said head co-axially of said spindle entirely forwardly thereof, said head comprising an integral body member having a longitudinal bore therein inclined inwardly and forwardly relative to the axis of said spindle and intersecting the projection of same within the forward portion of said head, a countershaft located in said bore and bearings received within the latter for rotatably supporting said countershaft therein, collet means incorporated in said countershaft and a cylindrical milling cutter chucked in said collet means, said milling cutter having its cutting surface disposed astride the axis of said head within said bore, a bevel gear fast on said countershaft at the rear thereof, a pinion in meshing engagement with said gear, and a second spindle journaled within said hollow spindle to which said pinion is secured, said second spindle being substantially coterminal forwardly with said hollow spindle, and driving means for driving said spindles in the same direction but at different speeds, a work holding jig removably secured to the forward end of said head, and an aperture therein concentric with the axis of said head and extending into communication with said bore to provide access for bolts received in said jig aperture to said milling cutter.

7. Apparatus as defined in claim 6, wherein said milling cutter has helically inclined teeth with the helix inclined, relative to the direction of rotation of the cutter, to draw the work inwardly of said head when contact is established with said cutter.

8. Apparatus as defined in claim 6, wherein said milling cutter is axially shiftable in said collet.

9. Apparatus as defined in claim 2, which includes a pair of countershafts diametrically opposed within said head, each of said shafts having gear means secured at its rearward end in meshing engagement with said pinion on said inner spindle, and each shaft having a beveled milling cutter at its forward end, the adjacent cutting surfaces of said milling cutters forming an acute included angle bisected by the axis of said head and disposed immediately adjacent the inner end of said aperture in said jig.

10. Apparatus for pointing the ends of bolts, screws and the like, which comprises a pointing head and a hollow spindle having a flange at one end, journal means rotatably supporting said hollow spindle, means for removably securing said head to said flange to support said head axially on said spindle entirely forwardly of said journal means, said head comprising a generally cylindrical body member having diametrically opposed bores running generally longitudinally of said head but skewed head, a 'countershaftlocated in each of said bores and bearings received within the latter for rotatably supporting the respective countershafts, a generally cylindrical milling cutter secured to the forward end of each of said shafts whose adjacent cutting surfaces form an acute included angle bisected by the axis of said head, each u of said shafts also having a bevel gear secured to their respective rearward ends, a pinion disposed intermediate said bevel gears and meshing with both at diametrically opposite points on its periphery, a second spindle jour naled within said first to which said pinion is secured, said second spindle being substantially coterminal at its forward end with the forward end of said hollow spindle, and means for rotating said spindles in the same direction but at independent speeds; a work holding jigremovably secured to the forward end of said head and an'aperture therein concentric with the axis of said head and extending into communication with said milling cutters.

11; Apparatus as defined in claim IOyWherein said head is formed with a ce'ntrallubricant manifold and ducts leading therefrom to each of said countershatt bearings, said a second spindle being provided with a lubricant duct communicating within said vhead with said central manifold. V v 7 References Cited by the Examiner I UNITED STATES PATENTS 7 894,600' 7/08 Chadwick r 144-30 1,206,450 11/ 16 Myers 144-30 1,292,781 1/19 Hopkinson 90-1153 1,475,978 12/23 Westerman 74 9660 1,532,167 4/25 Weiler "120- 96 I I FOREIGN PATENTS 1,223,421 1/60 France.

ANDREW R JUHASZ Primary Examiner.

WILLIAM 'DYER,JR,, Examiner.

Claims (1)

1. IN APPARATUS FOR POINTING THE ENDS OF BOLTS, SCREWS AND THE LIKE, A SUPPORTING FRAME, SUBSTANTIALLY COTERMINAL, COAXIALLY TELESCOPING INNER AND OUTER DRIVING SPINDLES JOURNALED FOR ROTATION ON SAID FRAME, MEANS FOR DRIVING SAID SPINDLES INDEPENDENTLY OF EACH OTHER IN THE SAID DIRECTION OF ROTATION BUT AT DIFFERENT SPEEDS, A HEAD SECURED TO ONE OF SAID SPINDLES ENTIRELY FORWARDLY THEREOF FOR ROTATION THEREBY, A COUNTERSHAFT BEING INCLINED INWARDLY TOWARD THE FREE SAID COUNTERSHAFT BEING INCLINED INWARDLY TOWARD THE FREE END OF SAID HEAD, A DRIVING MEMBER SECURED TO SAID COUNTERSHAFT AND A COMPLEMENTARY DRIVING MEMBER FAST WITH THE OTHER OF SAID SPINDLES, SAID MEMBERS BEING INTERCONNECTED FOR DRIVING ENGAGEMENT, A ROTARY CUTTER CARRIED BY SAID COUNTERSHAFT AT ITS FORWARD END AND PROVIDING A CUTTING SURFACE DISPOSED AT AN ACUTE ANGLE TO THE AXIS OF ROTATION OF SAID HEAD, AND A JIG MOUNTED AT SAID FORWARD END PORTION HAVING AN AXIALLY DISPOSED APERTURE FOR SLIDING RECEPTION THEREIN OF BOLT AND SCREW BLANKS TO GUIDE THE INNER ENDS THEREOF INTO CONTACT WITH SAID CUTTER.

Images