US1409102A - Metair-working machine - Google Patents

Description

B. M. W. HANSON. METAL WORKING MACHINE- APPLICATION FILED APR.28. 1920.

Patented Mar. 7,

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UNITED STATES.

BENGT M. W. HANSON, OF HARTFORD, CONNECTICUT.

METAL-WORKING MACHINE.

Specification of Letters Patent.

Patented Mar. '7, 1922.

Application filed April 28, 1920. Serial No. 377,267.

To all whom it may concern:

Be it known that I, BENGT M. W. HANSON, a citizen of the United States, and a resident of Hartford, county of Hartford, State of Connecticut, have invented certain new and useful Improvements in a Metal-VVorking Machine, of which the following is a specification.

The present invention relates in its more general application to metal working machines adapted for, operation 'on curved surfaces, for instance, machining or finishing the same, and has as its aim to so organize the parts of the machine that the operations may be carried out on the work with the greatest efliciency, particularly as to accuracy, uniformity and expedition.

The various features of construction present in the machine will be described with reference to their use in a machine for grinding holes, but it is to be understood that the present disclosure is by way of illustration only and is not to be taken as restrictive of my conception, for while the invention has particular adaptability to this use, it is susceptible of other uses.

It has been the practice in grinding holes to employ a grinding wheel usually of less lengtlrthan the hole and supported at one side only, to feed the work to the grinding wheel one step after the completion of one out and before the commencement of a new one, and to move the grinding wheel in one direction-lengthwise of the hole during each cut so as to grind the hole from one end to the other. In accordance with the embodiment of the present invention, herein selected for illustrative purposes only, the grinding wheel is supported at each end so as to be substantially free from vibrations; the grinding wheel is preferably longer than the hole which is being ground, and the work by preference is fed with a uniform motion to the grinding wheel during the grinding operation so that the hole is uniformly ground throughout its length and no time is wasted in relatively feeding the work and tool; and the grinding wheel is reciprocated longitudinally across the surface of the work so that a smooth finish is obtained; all of which is of advantage over the practice heretofore followed in that work of greater accuracy and finish may be had with a saving of time and labor.

In the accompanying drawings:

Fig. 1 is afront elevation of the machine,

the lower part of the broken away.

Fig. 2 is a right hand end view thereof, a portion of the pedestal being in vertical section, taken substantially on line 22 of Fig. 1, and a portion of the gear box from which the Worlcholder is driven being broken away.

Fig. 3 is a top plan view.

Fig. 4 is a vertical sectional view taken substantially on line H, Fig. 2, through the work support and the head and tail stocks, all other parts being omitted except portions of the pedestal and the tool carfiage which'are shown more or less in out- Fig. 5 is a side view of a portion of the upper end of the work support, a bearing ring 42 thereof being omitted, and the work chuck, the work and the tool being in section.

pedestal thereof being Fig. 6 is an enlarged detail view in front elevation, with parts broken away, of the mechanism by which the reciprocating movement of the tool carriage is converted into rotary movement of the work feeding cam.

Fig. 7 is a vertical sectional view taken centrally through the structure shown in Fig. 6.

Fig. 8 thereof.

Fig. 9 is an enlarged detail view in vertical transverse section of the upper end of the work support.

Fig. 10 is a front view of the mechanism for feeding the work relative to the tool.

Fig. 11 is a view of the mechanism for imparting a reciprocating movement to the tool carriage.

Fig. 12 is a view of an escapement ratchet clutch forming part of the mechanism of Fig. 11, and

Fig. 13 is a vertical sectional view taken on line 13-l3, Fig. 3, through the tool carriage. 4

From Figs. 1, 2, 3 and 4, the general organization and arrangement of the principal parts of the machine maybe clearly seen. a is the pedestal having a fixed top plate 10 on which the tool carriage, designated generally by the letter 6, is reciprocated in short strokes through the instrumentalityof a suitably driven pinion 14 meshing with a rack 15 on the tool carriage, as clearly shown in dotted lines Figs. 1 and 2. On this tool carriage are slidably supported, as hereinafter described more in is a horizontal sectional view holder, such as a chuck 71, carrying the work ofvthe change s eed J) and its associated parts.

W, herein shown as being in the form of a bushing. The work support is swung in its bearings c to feed the work relativev to the tool, by means of a feeding cam n cooperating with a roller 0 on the lower end of the work support 7. A spring 9 connected between the pedestal and the work support serves to maintain the roller 0, against the feeding cam. Preferably, the work V is fed with a uniform motion to the tool during the reciprocation of the latter, and to this end the reciprocating movement of the tool carriage b is converted into substantially continuous rotary movement of the feedingcam by the device 7), herein referred to for convenience as a motion 'converting device. On the left hand side of the machine is a gear box is from which is driven the pinion 14, and on the right hand side of the machine is mounted a gear box Z, through the change Speed gearing of which the work holder or chuck z' is rotated at a relatively slow speed as will be hereinafter described more in detail. The pulleys gearings may be driven in any suita le manner as from a countershaft, not shown. The head stock spindle 11 carrying the toolis driven at a high rate of speed ,by belts 32 passing about a drum 34 driven as by means of a belt 35 from the same co-untershaft as that from which the speed change gearing is driven.

From the foregoing brief description, it

v will be understood that. the grinding wheel is rotated at a high rate of speed while the bushing is slowly rotated about its axis;

the grinding wheel is supported at its opposite ends so ias to be free o-fvibration; the grinding wheel, while cutting, is reciprocated back and forth to insure uniform action and the work is fed with a uniform or continuous motion to the tool owing to the -cam-n being continuously rotated by the tool carriage b acting through the motionv converting device 1).

Reference may now. be had more particularly to the construction of the tool carriage The tool carriage 12 comprises a main plate 16 slidable on the top plate 10 of the pedestal a and having at each end and, if desired, intermediate its ends, standards 17 to which is secured a plate 18 having in its under surface ways 19 slidably receiving the ways 20 on the top surfaces of the bases of the head ving the pulley 31 on the carriage. It is of advantage to supthe under port the head and tail stocks from surface of the plate 18 in that grit or the like, for instanceemery from the grinding wheel, cannot gain access to the ways and gibs. It will be noted that the late 18 is inclined downwardly and forwardly so that any water or oil thrown onto the plate will readily flow off. The head stock is moved longitudinally of the plate 18 into and out of operative position relative to the work by the hand wheel 25 fixed to a shaft carrying a :pinion 26 meshing with a rack 27L on the head stock. Any suitable means for clamping the head and tail stocks in operating positions may be provided, for instance binders 29 shown in Fig. 2. The head and tail stocks carry suitable ball bearings 28 supporting the spindles 11 and 12. On the head stock spindle 11 is a fixed pulley 30 and on the tail stock spindle 12, a pulley 31 is frictionally mounted for reasons hereinafter stated and these pulleys aredriven by the belts 32 passing about drums 34 and over suitable idlers 33 mounted in brackets carried by and extending rearwardly from the head .and tail stocks. The drums 34 are mounted at the rear of the machine and may be driven from a countershaft by means of belts 35 shown in dotted lines Fig. 3.

It is of advantage tosupport the opposite ends of the arbor of the wheel T on the spindles 1.1 and 12, to prevent vibration and chattering of the'wheel which result in uneven and faulty work.

In accordance with the present invention, the tail stock manner that the arbor of the grinding wheel may be brought into cooperative relation therewith, .while the grinding wheel is rotating at high speed, without setting up any influences tending to interfere with the smooth and regular rotary movement of the grinding wheel. This is accomplished, in the present instance, by frictionally mount on the tail stock spindle, the friction between the s indle and the pulley being so adjusted that it is very slightly greater than the friction offered by tlieb'earings in which the spindle is mounted, and by driving the. pulley .31 at a very slightly greater speed than the head stock spindle 11. This means that when the spindle 12 is not supportingthe tool arbor, this spindle Will rotate substantially in unison with the pulley 31, i. e., at a speed slightly greater than the tool arbor which is then being carried only by the rotating spindle 10, and when the rotating tool arbor is spindle 12, is driven in such brought into engagement with the spindle 12, this spindle will slow down to the speed of the arbor and the pulley 31 will run ahead of the spindle 12 without exerting enough driving force on the spindle to have any appreciable effect. With this arrangement, it is not necessary to start and stop the rotation of the grinding wheel when the tool arbor thereof is moved into and out of engagement with the tail stock spindle. In one manner of speaking, the end of the grinding wheel arbor has a bearing in the spindle 12 and this spindle is in the nature of a rotating bearing member which is so driven that it exerts no drag or wear on the arbor.

While in the preferred embodiment illustrated in the drawings the pulley 31 is frictionally mounted on the tail stock spindle 12 and is driven at a slightly greater speed than the head stock spindle, if desired the arrangement ma be such that the tail stock spindle and the head stock spindle are positively driven at the same speed.

The work suppoi t f has laterally extend- 7 ing trunnions 40, the outer ends of which are supported in bearings e on the front of the pedestal a. In the circular head 13 of this support is fixed a pair of complementary bearing rings 41, 42, between which is supported a rotary ring 43 carrying the chuck 2' which may be of any suitable construction. It will be noted that the opposed bearing faces of the rings .41, 42, are inclined towards one another, this being of advantage in that a relatively large bearing surface is provided for the ring 43 without increasing the width of the head of the work support. A ring like gear- 44 having a bearing on the bearing ring 41 is driven, as most clearly shown in Fi s. 2 and 4, through the gears45 by the s aft 1" which is connected to the change speed gearing Within the gear box Z. The gear 44 is yieldingly or flexibly connected to the ring 43 so that the ring 43 will run smoothly and regularly, free from any disturbances resulting fromthe driving mechanism therefor, and to this end, as shown most clearly in Figs. 5 and 9, the periphery of the ring 43 is interrupted by notches 46 which receive small blocks 47 of a yielding material such as leather and each of these blocks is secured to the gear 44 by screws 48- The associated rings 49 form oil guards which may be of any suitable construction.

Reference will now be had to the means for feeding the work to the tool. This means, as stated, comprises in part the feeding cam 'n having a spiral circumference cooperating with the roller 0 on the dependlng leg of the work support 7. This cam is fixed on the shaft 55 journaled in the forward end of-a slide 56 mounted on a suitable support 57 which may be a part of the pedestal a. For the purpose of adjusting the slide 56 and thereby roughly adjusting the Work support and the work carried thereby to the tool, a screw 58 journaled in a bearing on the support 57 and having threaded engagement with the slide 56 is provided and this screw is connected by gearing 59 including the shaft 60 to a'shaft 61 on'the forward end of Which is a hand wheel 62. Fixed to the shaft 55 is a worm gear 63 with which meshes a worm 64 splined on a shaft 65 connected through bevel gears 66 and a shaft 67 to a shaft 68 passing through the device 10 and carrying on its forward end a hand wheel 69 whereby the cam 11 may be angularly set with respect to the roller 0 of the Work support.

The motion converting device p from'v which the shaft 68 (through which the feeding cam n is driven) derives its motion from the reciprocating movement of the tool carriage b, is most clearly shown in Figs. 6, 7 and 8. Secured to the tool carriage b is a plate 72 to which is pivoted for angular adjustment a guide member 73 adapted to be locked in adjusted position by a screw 74. On the outer face of the guidemember 73 is a dove-tail groove in which works a block 75 adapted to be detachably secured by means of a pin 76 to the head of the recipro-' cating member 77 having a pair of opposed racks 78, 79, straddling the shaft 68. This reciprocating member is housed within a casing'81 and is normally urged upwardly by the spring pressed plunger 82. Carried by the shaft 68 is a ratchet wheel 83 having a. hub at each side upon which are freely mounted segmental gears 84 meshing with the respective racks 78, 79. Each of these segmental gears has an arm on which is pivoted a pawl 85, both pawls being headed in the same direction and cooperating with the ratchet wheel'83. It will be readlly observed that when the tool carriage is moving to the right, referring to Figs. 1 and 6, the guide member 73 moves therewith, the block 75 will ride down the groove in the guide member resulting in therack member 77 moving downwardly, the rear segmental gear 84 with Which rack 79 is in mesh will be rotated in a clockwise direction, and since the pawls 85 are active when moved in this direction, the shaft 68 is rotated. In the meanwhile, the rack 78 is rotating the front segmental gear counter-clockwise and the pawl 86 thereof rides freely over the teeth of the ratchet wheel. When the tool carriage moves to the left, the member 77 will move upwardly and the rack 78 will move the front segmental gear 84 clockwise, resulting in rotation of the ratchet wheel and the shaft 68 in the same direction as when the rack member 77 was lowered. Thus, on movement of the tool carriage in either direction, the shaft 68 and the feeding cam driven therethrough will be rotated subvaried by angularly adjusting the guide member 73. The more nearly the groove of this guide-member is to a horizontal plane,

the slower is the rate of rotation of the feeding cam.

.It may be desirable in some, instances, instead of thus feeding the i work to the tool during the cutting operation,- to follow the practice heretofore used of feeding the work to the tool with a step by step movement, and take successive cuts in the work.- To this end the arrangement is such that the rack member 77 of the device 10 may be disconnected from the block 75 and connected to a mechanism which is actuated only when the tool carriage reaches the'ends of its strokes. As herein -shown, this mechanism comprises a link 87 pivotally carried by a bracket on the pedestal aand connected at one end through link 88, crank 89 and link 90 to a lever 91, pivoted, as shown, to the pedestal a and having its upper end positioned between a pair of dogs 92 adjusta-bly carried by the tool carriage b. The opposite end of the link 87 is adapted to be detachably connected to the rack member 77 by means of the pin 76 or in any other suitable manner, A c mpression spring93 is provided for holding the link 87 so that it will not be in the way when the rack member 77 is connected to the block 75.

The driving mechanism for imparting a reciprocating movement to the tool carriage may be of any suitable construction, but for illustrative purposes, I have shown more or less conventionally a mechanism 1n Fig.

11 which may be used to advantage. On the lower end of the shaft carrying the pinion 14 is a bevel gear 94 meshing with oppositely disposed bevel gears 95 on a shaft 96 driven through suitable speed change gearing within the gear box is, this gearing not being shown as it may be of any suitable type. On the main shaft 97 of the speed changing mechanism' within the gear box is, is a ratchet wheel 98 with which cooperates a spring pressed pawl 100 carried by a'disk 101 fixed to a cam shaft'102 having a cam groove in which operates a roller carried by a shipper 103 associated as shown with the clutches 104; of.the bevel gears 95. The pawl 100 is controlled by an escapement yoke 105 slidable on a pin 106 and connected by a rod 107 to a lever 108 which, in turn, is connected 'by a link 109 to the lever. 91. It will be readily understood that when the tool carriage reaches either end of its stroke, the escapement yoke is moved to withdraw one .end thereof from the pawl and bring the other end of the yoke into the path of the pawl thus permitting the pawl to intermitto move the slide 56 with the roller 0 against tently cooperate with the continuously driven ratchet wheel 98, whereby the cam shaft 102 is intermittently rotated through one-half revolution and the shipper is shifted to actuate the clutches 104 and alternately connect thebevel gears to the shaft 96.

To set up the machine for a given piece of work, a .test piece, having a hole of some what less diameter than that to which the hole in the work is'to be ground, is positioned with the chuck 6;, either the change speed gearing of the driving mechanism for reciprocating the tool carriage is thrown out of operation orthe motion converting device p is disconnected so that it will not be operated upon reciprocation of the tool carriage and therefore the feeding cam n will not be automatically rotated during operation upon the test piece; the head stock 0 is movedto position the grinding wheel with-. in the'hole in the test piece; the high point of the feeding cam n is brought into engagement with the roller 0 on the depending leg of the work support f by manually turngearin within the gear box Z is thrown into operation to effect rotation of the chuck z carryin the test piece; (it will be remembered t at due to the-manner in which the tail stock spindle 12 is driven it is unnecessary to interfere with the rotation of the grinding wheel when it is desired to move the same into and out of operative position) then the operator by manually turning the hand wheel 62 slowly moves the slide 56 on which the feeding cam n is jour naled to feed the test piece to the grind ing wheel, and the operator continues so the high point of the'feeding cam until he has determined by measurement that the hole in the test-piece has been ground to the same diameter as that to which the hole in the work is to be ground.

WVithout disturbing the position of the slide 56, the test piece is now taken out of the chuck z and the bushing or work lV inserted in its place; the reciprocating member 77 of the device 72 is connected to the block 75, and the feeding cam n is manually rotated by means of the hand wheel v62 to bring the low point of the cam n into engagement with the roller 0 on the work support; the grinding wheel T is moved into operative position within the hole in the work, and then the driving mechanisms for reciprocating the tool carriage b and rotating the chuck 2' are thrown into operation and the grinding proceeded with. The feeding cam is continuously or uniformly rotated in the direction of the arrow, Fig. 2, due to the reciprocating movement of the tool carriage b acting through the motion oonverting device ;0 as heretofore described in detail. Thus, it will be seen that the grind- 130 scribed, a rotatable work holder, a grinding ing wheel is lon itudinally reciprocated back and forth wh1le operating throughout the entire length of the bushing and during such reciprocation-of the grinding wheel the work is fed thereto with a uniform motion. When the feeding cam has been rotated to the extent that the high point thereof reaches the roller 0 on the work support, it is of course evidentthat the hole in the work is of the correct .size, for this cam is now in the same position as when the grinding operation on the test piece was terminated, it being remembered that, after operation on the test piece the adjustment of the slide 56 is not disturbed.- After the machineis set for grinding one hole, it will grind the holes of all subsequent pieces to the same exact size.

It is of course evident that my invention is susceptible of various modifications and changes which are within the spirit of the invention without departing from the scope of the following claims, it being understood that the present disclosure of my invention is by way of illustration only and it is not to be taken as restrictive of my conception.

What I claim is:

1. In a machine of the character described, a rotatable work holder, a grinding wheel, means for rotating said holder, means for reciprocating said grinding wheel and holder longitudinally one relative to the other during the grinding operation, and means for uniformly feeding said grinding wheel and holder one relative to the other during such reciprocating movement.

2. In a machine of the character dewheel, means for rotating said work support and grinding wheel, means for reciprocating said grinding wheel longitudinally of the work holder, and automatically operated means for feeding the work relative 'to the grinding wheel, both of said last mentioned means being operated during the grinding operation.

' 3. In a hole grinding machine, a work holder. a grinding wheel extending through the hole in the Work and supported at each side of said work holder, means for rotating said grinding wheel, and means for continuously feeding said Work holder and grinding wheel one relative to the other during the grinding operation.

4. In a hole grinding machine, a rotatable work holder, a grinding wheel extending through the hole in the work, means at each side of said work holder for supporting the opposite ends of said grinding wheel, means .for reciprocating said grinding wheel across the surface of the work, and means for feeding said work holder relative to said grinding wheel during the cutting operation of the latter.

5. In a hole grinding machine, a rotatable 'through and of greater length than the hole to be ground, means at each side of said work holder for supporting the opposite ends of the grinding wheel, meansfor reciprocating the grinding wheel longitudinally across the surface of the work, and automatically operated means for uniformly feedingthe work to the grinding wheel during the grinding operation.

7. In a hole grinding machine, a work support, a tool carriage having a head stock and a tail stock mounted thereon and supporting a tool therebetween, means for reciprocating said tool carriage, and means actuated by the reciprocation of said tool carriage for uniformly feeding the work relative to the grinding wheel during the entire extent of travel of said tool carriage.

8. Ina hole grinding machine, a slidable carriage, a head stock and a tail stock carried thereby, a tool supported therebetween,-

9. In a hole grinding machine, a tool carriage, means for reciprocating the same, a

work support, and means actuated by the reciprocating movement of said tool carriage for uniformly feeding the work support relatively to the tool during the reciprocation of said tool carriage.

10. In a hole grinding machine, a carriage, means for reciprocating the same, a head stock and a tail stock on the carriage, a tool supported therebetween, a pivoted work support including a rotatable work holder positioned between said stocks and encircling said tool, and means operated by the reciprocating movement of said tool carriage for uniformly swinging said support about its fulcrum to uniformly feed the work to said tool.

11. In a machine of the.character described, a tool carriage, a tool thereon, means for reciprocating the tool carriage, a pivoted work support, a rotatable work holder thereon, means for rotating said work holder, means cooperating with said work support for swinging the same about its fulcrum to feed the work to the tool, and a motion converting device between the tool carriage and feeding means for unifor uniformly operating said feeding means during reciprocation of the carriage, said device including means for varying the rate of feed of the work to the tool.

13. In a machine of the character described, a tool carriage, a tool thereon,

means for reciprocating said carriage, a pivoted work support, a rotatable work holder thereon, means for rotating said work holder,

means for rotating said cam.

- ing said slide,

a feeding cam cooperating with said work support for swinging the same about its fulcrum to feed the-work to the tool, and means between the tool carriage and the cam for uniformly rotating said cam during the reciprocation of said carriage.

14. In a machine of the character described, a work support, a cam cooperating therewith, a slide in which said cam is journaled, means for adjusting said slide, and

15. In a machine of the character described, a work support, an actuating cam therefor, a slide in which said cam is jour naled, manually operable means for adjustand automatically operated means for rotating said cam.

16. In a machine of the character described, a tool carriage, a pivoted work support, a cam in cooperative relation with said support, a slide on which said cam is ournaled, means for adjusting said slide, and means operable by said tool carriage for rotating said cam. 4

17. In a machine of the character described, a horizontally extending member, and a tool stock slidably supported from the under side of said member.

18. In a machine of the character described, a forwardly inclined member, a tool stock having a base'portion positioned beneath said member, and cooperating ways on the under side of said member and the top of said base portion.

19.. In a machine of the character described, a tool carriage including a base havstock having a base ing spaced standards arising therefrom and a plate secured on said standards, a tool portion positioned beneath said plate, and cooperating ways on the underside of said plate and the top of said base portion of the tool stock. 20. In a machine of the character described, a pair of spindles cooperatively positioned to support a part therebetween,

bearings therefor, means for positively driving one of said spindles, and means for frictionall driving the other of said spindles.

21.--n a machine .of the character described, a head and a tail stock spindle, bearings therefor, means for positively driving. the head stock spindle, frictional driving means normally tending to drive the tail stock spindle at a slightly greater speed than the head stock spindle, the frictional 'said tail stock spindle and the bearing therefor.

23. In a machine of the character described, a reciprocating tool carriage, a work support, rotatable means for feeding said work support, means for converting the reciprocating movement of said carriage into rotary movement of said feeding means, means adapted to be detachably connected to said device and actuated by said tool carriage at the end of each stroke for rotating said feeding means step by step, and means carried by the tool carriage and adapted to be detachably connected to said device for uniformly rotating the feeding meansv dur ing reclprocation of said carriage.

24. scribed, a reciprocating carriage, a guide member thereon having a groove, a .slidev block in the groove, means including a sta- In a machine of the character de-' tionarily pivoted lever actuated by said carriage at the end of each stroke thereof, a

work support, rotatable feeding means there- I for, a motion converting'device associated therewith and having a reciprocable rack member, and means for detachably connecting said lever or said block to said rack member. 7 4

25. In a machine of the character described, a spindle, a rotating bearing member cooperatively positioned relative thereto, a part connectedto said spindle and having a bearing adapted to rotate in said bearing vmember, and means for driving said spindle.

26. In a machine of the character describefi), a spindle, a rotating bearing mem- I her 0 peratively positioned relative thereto, a part connected to said spindle and hav-. ing a bearing freely rotatable in said bearing member, means for driving said spindle,

grid means for rotating said bearing mem- 27. In a machine of the character described, a spindle, a rotating bearing member cooperatively positioned relative thereto, a part connected to said spindle and having a bearing in said bearing member, means for driving said spindle, and means for frictionally driving said bearing member.

28. In a machine of the character described, a spindle, a bearing member cooperatively positioned relative thereto, bearings for said spindle and bearing member, means for positively driving said spindle, and frictional driving means normally tending to drive said bearing member at a slightly greater speed than said spindle.

29. In a machine of the character de? scribed, a pair of alined spindles positioned to support a member therebetween, driving means at each end thereof, one of said driving means being frictionally mounted on one of said spindles and adapted to be driven at a different speed relative to the other of said driving means.

30. In a machine of the character described, a pivoted Work support, a rotatable cam cooperative with said Work support to rotate the latter about its axis, and a slide supporting said cam and adjustable at right ble Work holder adapted to support tubular pieces of Work, a grinding Wheel extending into and surrounded by said holder, means for rotating said holder, means for reciprocating said grinding Wheel longitudinally relative to said holder during the grinding operation, and means for uniformly feeding said holder relative to said grinding Wheel during such reciprocating movement.

BENGT M. W. HANSON.

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