US1118442A

US1118442A - Cam-cutting machine.

Info

Publication number: US1118442A
Application number: US32857006A
Authority: US
Inventors: Albert J Povah
Original assignee: United Shoe Machinery Co AB
Current assignee: USM Ltd; United Shoe Machinery Co AB
Priority date: 1906-07-31
Filing date: 1906-07-31
Publication date: 1914-11-24
Anticipated expiration: 1931-11-24

Description

A. J. P OVAH.

CAM CUTTING MACHINE. APPLICATION FILED JULY 31,1906.

Patented Nov. 24, 1914.

4 SHBETS-SHEBT 1.

A. J. POVAH.

0AM CUTTING MACHINE.

APPLIGA'L'IUN FILED JULY 31, 1900 1,1 18,442. Patented Nov. 24, 1914.

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CAM CUTTING MACHINE. APPLICATION FILED JULY 31, 1906.

1 1 1 8 ,442, Patented Nov. 24, 1914.

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0AM CUTTING MACHINE.

.xlruulxrlox FILED JULY 31, 190s.

l 1 1 8,442. Patented Nov. 24, 1914.

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:rr STATES, PATENT, OFFICE.

ALBERT J. POVAH, OF SOUTH BOSTON, MASSACHUSETTS, ASSIGNOR TO UNITED SHOE MAGHINEBY COMPANY, OF PATERSON, NEW JERSEY, A CORPORATION OF NEW JERSEY.

CAM-CUTTING MACHINE.

Specification 01 Letters Patent.

Patented Nov. 24, 1914.

Application filed July 31, 1906. Serial No. 328,570.

To all whom it may concern Be it known that I, ALBERT J. Povau, a citizen of the Unitedv States, residing at South Boston, in the county of Suffolk and 5 State of Massachusetts, have invented cer-.

In a ca m mechanism operating at. high speed it 1s necessary, 1n order that the wear on the cam and cam roll, and the noise incident to theiroperation, may be reduced to a minimum, that thecam surfaces be accurately formed so that, in all positions to which the cam roll'is moved by the joint action of the cam and the mechanism upon which the cam roll is mounted thecam path and the cam roll shouldaccurately engage each other over the whole or a substantial part of the width of their bearing surfaces, for if they engage only at a single point this point .will be rapidly worn or hammered away and the operation of the mechanism Will become inaccurate and noisy. It is also necessary, where a cam of the closed type is used, that the cam groove in which the cam roll is moved be of a width only sutlicient to permit the cam roll to pass freely therethrough, for any looseness sufl'icient to allow substantial lost motion will result in hammering of the cam roll against the cam and the rapid deterioration of the .parts.

When the cam roll is mounted on a slide movingparallel to the axis of rotation of the cam, or on a lever pivoted to oscillate only in a plane perpendicular to the axis of the cam, the formation of a correct cam surface or groove is con'iparatively simple and may be accomplished by a cam-cutting machine of ordinary form, having a cutter mounted on a sliding carrier controlled by a pattern plate or leader. But where the cam roll is so mounted that its axis does not remain in the same plane as the axis of rotation of the cam, as, for example, where the cam roll is carried by a lever mounted to oscillate about an axis not parallel with the axis of the cam, the form of the cam surface necessary to engage the cam roll accurately in all positions is not such as can be generated accurately by a cam-cutting machine of the ordinary form. It has been customary, therefore, to out such cams on an ordinary machine and then to scrape the cam surfaces in order to make them approximate more nearly the correct form. This method is expensive, however, and does not result in a perfect cam, being particularly unsatisfactory 111 the case of a closed cam, in which the scraping of the roove at certain points results in variations in the,width of the groove and in consequent loosencss. result ing in hammering of the cam roll when in operation and lost motion in the mechanism actuated thereby.

The object of this invention is to produce a cam-cutting machine in which cams ol the character above referred to may be cut 1n an accurate manner so as to obviate hand work or other finishing operation and the resulting disadvantages.

The present invention is particularlv adapted for cuttin the cam by which the looper is actuated 1n the well-known Good year type of shoe-sewing machine. The looper cam of the Goodyear machine is a dapt ed to impart a compound oscillating movement to a lever mounted on a universal fulcrum which permits oscillations in all direc tions, and, owing to the peculiar movement of this lever and the cam roll the correct cam path for actuating these parts isof an irregular form which can be only roughly approximated by an ordinary canrcutting machine.

The' invention consists in the improved canrcutting machine hereinafter described and defined in the claims.

In the drawings Figure 1 is a front elevation of an improved cam-cutting machine embodying in preferred form the present invention; Fig. 2 is a right-hand end elevation; Fig. 3 is a left'hand end elevation. and Fig. 4 is a plan view.

In the illustrated embodiment of the invention, which is a machine adapted to cut both peripheral and lateral cam grooves or surfaces on a circular cam blank, the blanks are mounted and rotated in substautiall y the same manner as in previous cam-cutting machines,'but the milling cutters by which the cam, surfaces are formed are mounted upon and directed by pivoted levers which, in respect to their length and the point at which they are pivoted, have the same relation to the cam blanks as the cam lever of the ma chine in which the cam is to be used has to the cam in said machine. The machine is, for convenience, provided with two blanksupporting mandrels and two cutter-carrying levers, so that a cam having both peripheral and lateral grooves or surfaces may be cut in two operations, and so that two cam blanks may be operated upon in the machine at one time.

Considering first the mechanism for cutting peripheral cam surfaces, the cam blank 1, Figs. 2 and 4, is secured to a mandrel 2 journaled in columns 3 mounted on the bed plate 4 of the machine. A rotary millmg cutter 5 is fixed to a short shaft 6 journaled in one end of a lever 7. The cutter lever 7 1S pivoted in a fork 8, Figs. 1 and 4:, having a stem 9 pivotally mounted in a standard 10 on the bed-plate of the machine, this construction forming a universal joint permitting oscillating movements of the cutter lever 7 in every direction. The milling cutter 5 is rotated by a flexible shaft 11 connecting the shaft 6 with a stepped driving pulley 12 actuated by belt connections with a suitable source of power.

In order to guide the milling cutter 5 so as to generate the proper contour on' the periphery of the cam blank, a guide roll 13 is mounted on the left-hand end of the cutter lever 7, this guide roll resting upon a pattern plate or leader 14: which is mounted upon a mandrel 15 parallel to the camblank mandrel 2. -As the milling cutter operates upon the cam blank, the latter is slowly rotated to feed new portions of its surface to the milling cutter, and the leader 14 is simultaneously rotated at the same speed and in the same direction to guide the milling cutter. The mandrels 2 and 15 carry at their outer ends worm wheels 16 and 17 respectively which are engaged by worms 18 on a worm shaft 1 The worm shaft 19 is connected by bevel gears 20 with a sleeve 21. j ournaled in a lug 22 on thebed plate of the machine and concentric with a feed shaft journaled at one end'in the sleeve 21 and at the other end in :1 lug 2 1 on the bed plate. The sleeve 21 has formed at one end a series of clutch teeth which may be engaged by a sliding clutch member 25 splined to the feed shaft 23 and free to be moved longitudinally thereon by the operator in order to connect or disconnect the worm shaft and feed shaft to start or interrupt the feed. The feed shaft 23 carries at its rear end a cone pulley 26 connected by a belt 27 with a corresponding cone 28 (see Fig. 2) which is journaled on the frame of the machine. The cone pulley 28 is connected by a sprocket chain 29 with a sprocket 30 driven by the driving pulley 12.

By shifting the belt 27 on the cone pulleys the rate of feed of the cam blank and leader may be varied. according to the size or material of the cam'blank.

The pivotal support of the cutter lever 7 "is arranged midway between the'ends so that p the movements lmparted to the guide-roll machine is shown as operating at its righthand portion upon an irregular cylindrical cam, and therefore a single leader is used in this part of the machine, the capacity of the cutter lever 7 for oscillating in a horizontal plane not being utilized. Accidental oscillations in a horizontal direction are prevented when the machine is used in this manner, by tightening the nut 31 on the bottom of the stem 9 forming partof the joint on which the cutter lever 7 is mounted.

To adapt the machine to cut cams of different widths and diameters, and cams for actuating'cam levers of different lengths, horizontal adjustments are providedfor the columns upon which the cutter lever and the mandrels are mounted. The column 10 on which the cutter lever 7 is mounted is connected by a bolt 32 with a T-slot. 33 in the base plate of the machine so that it may be moved forwardly and rearwardly ac=- cording to the width of the cam blank op erated upon, and the columns on which the mandrels are mounted are similarly secured to the base plate by means of T-slots 34: which permit lateral adjustment of the mandrels for the use of cutter levers of different lengths corresponding to cam levers I of different lengths. The driving pulley 12 is similarly mounted to permit lateral adjustment, though this is not always necessary, owing to the use of the flexible shaft.

The left-hand portion of the machine is arranged to cut peripheral cam grooves. As shown in the drawings, it is'arranged to cut a peripheral groove in a cam blank on which a peripheral cam surface has already been formed in the righthand portion of the machine. The

mandrels

35 and 36 upon which the cam blank and the leaders are carried are substantially similar in construction and operation to those of the right-hand part of the machine, and the feeding means are identical with those of the right-hand part. The cutter lever 37 is mounted in the same manner as the cutter lever 7. A milling cutter 38 is journaled in a vertical position on the lever 37 and is driven by a flexible shaft 39 connected with a shaft 40 j ournaled in a housing il on the frame of the machine. The shaft 40 is connected by bevel gears 42 with a horizontal shaft 43 connected by gears 44 with a driving pulley 45 connected by a belt with a suitable source of power.

In order to keep the milling cutter 38 in proper engagement with the periphery oi the cam blank 46 on the mandrel 35 the cutter lever 37 isprovided with a.

.mounted on 'the mandrel 36, the leader 45) being engaged by a guide roll 50 (see dotted lines in Fig. 1) carried by the cutter lever 37. The cam roll 50 is maintained in engagement with the leader 1-9 by means of a spring 5l connected with the cutter lever 37 and with the frame of the machine. As the cam blank 4-6 and the leaders 4S and 49 are rotated slowly in unison, the milling cutter, while rotating and cutting the groove in the cam blank, moves with relation to the cam blank precisely as the cam roll moves with relation to the cam in the machine in which the cam is to be used, and thus the cam grooveis cut in precisely the proper form to engage the cam roll accurately in all posi tions.

In order to l ed the milling cutter 38 into the blank at the commencement of its operation, the milling cutter is mounted on a shaft 53 (see Fig. 1) journaled in a sleeve 54.- threaded into the end of the cutter lever 37. The sleeve is provided with a hand wheel by which it may be turned to advance the cutter longitudinally into the cam blank.

By simple rearrangements of the parts the machine may be arranged to cut lateral cam grooves or surfaces. To cut lateral cam grooves the feeding device comprising the shaft 553 and threaded sleeve 5-:l may be mounted in the right-handed end of the cutter lever 7, while the le't'tdiand portion of the machine may be arranged to cut a lateral cam surface by mere :ulj1u-1t1ncnt of the positions of the parts.

By using milling cutters of the same diameter and cutter-carrying lovers of the same length as the cam roll and cam lever in the machine in which the cam is to be used, and by mounting the cuttcr-carrying lever on a pivotal support having the same re ation to the cam blank that the support of the cam lever in the said machine has with respect to the cam, a cam may be out having a surface which will accurately engage the cam roll throughout its operation, the cam requiring no scraping or other work Where the machine is used to cut a cam with a groove, the groove, is of exactly the proper width throughout, so that there is no lost motion between the cam roll and the cam.

The invention is not limited to the details of construction and operation of the illustrated embodiment nor to the conjoint use of all its features, but may be embodied in other forms within the terms and spirit of the claims.

H aviug now described the invention, what is claimed is 1. A cam-cutting machine for cutting cams adapted to impart compound oscillations to a lever, having, in combination, means for supporting and rotating a cam blank, a cutter-carrying lever of substantially the length of the lever to be actuated by the cam, mounted on a universal joint to permit compound oscillation, means acting automatically to direct the oscillations of the lever, a rotary cutter journaled on the said lever and held in contactwith the blank, and means for rotating the cutter, substantially as described.

A cam-cutting machine, having, in combination, means for supporting and retating a cam blank, a cutter-carrying lever mounted between its ends on a i'lniversal joint, a rotary cutter journaled on one end of the love and held in contact with the blank, leaders engaging the other end. of the lever and acting to impart oscillations in two planes to the lever, and means for actuating the leaders, substantially as described.

3. A cam cutting machine having, in combination, means for supportmg and rotating a cam blank continuously in one direction, a cutter carr1er pivotally mounted to per mil; oselllations in two planes, a cutter carricd by the cutter carrier and held in engagement with the cam blank, and means for automatically oscillating the cutter carrier in said two planes as the blank is rotated, substantially as described.

4. A cam cutting machine, having, in combination, means for supporting a cam blank, means under the control of the operator for rotating the blank, a rotary cutter, a cutter carrier, means for positively rotating the cutter, manually operated means for mov ing the cutter in the direction of its length into the work, and means for automatically moving the cutter carrier in two planes as the blank is rotated, substantially as described.

5. A cam cutting machine, having, in combination, means for supporting and rotating a cam blank, a cutter carrying-lever, a rotary cutter supported thereby and held in contact with the blank, pattern cams operativcly connected to the lever and arranged to impart automatically oscillations in two planes to the cutter, and means for actuating the pattern cams, substantially as described,

6. A cam cutting machine, having, in combination, a supporting shaftt'or a cam blank, a pattern cam, a supporting shaft for the pattern cam parallel to the first mentioned shaft, a cutter carrier lever extending trans versely of the shafts and adapted "to be moved automatically by the pattern cam in two planes, and a cutter carried upon one end of 'the lever and held in engagement with the cam blank, substantially as de-- scribed.

7 A cam cutting machine, having, in com- Y bination, a supporting shaftfor a cam blank,- a supporting shaft for a pattern cam parallel thereto, means for simultaneously rotating the shafts, a cutter carrying lever, a cutter mounted on one end of the lever in operative relation to the cam blank, and a pattern cam operatively connected to the opposite end of the lever to impart automatically a universal movement to the lever and actuate the cutter in a path corresponding to the contour of the pattern cam, substantially as described.

8. A'cam cutting machine having, in combination, means for supporting and-rotating a cam blank, a cutter carrier mounted to oscillate in two planes, a cutter journaled on the carrier and held in engagement'with :the cam blank, means for automatically 0s cillating the cutter carrier in said two planes and means for positively rotating the cutter, substantially as described.

naled on the carrier. and held in engagement with the cam blank, means for rotating the cutter, and means for imparting automati- Cally-relative oscillating movements in two planes to the cam blank and cutter carrier, substantially as described.

10. A cam-cutting machine for cutting cams adaptedto impart compound oscillations to a lever, having, in combination,

means for supporting and rotating a cam blank, a cutterficarrier, a rotary cutter journaled on said carrier and held in contact with theblank, means for rotating the cut-' ter, and means tor imparting automatically relative oscillat ng movements to the cam blank and cutter carrier in two planes about a center located at a distance from the cutter substantially equal to the length of the lever to be actuated by the cam, substantially as described.

In testimony whereof I aflix my signature, in presence of two witnesses. ALBERT J. POVAH. Witnesses! v I FARNUM F. DOBSEY, ALFRED H. HILDRETE.