US3757638A

US3757638A - Five-axis shaper

Info

Publication number: US3757638A
Application number: US00243307A
Authority: US
Inventors: J Martin
Original assignee: Individual
Current assignee: Individual
Priority date: 1972-04-12
Filing date: 1972-04-12
Publication date: 1973-09-11
Anticipated expiration: 1990-09-11

Abstract

A heavy-duty combination vertical and horizontal metal-cutting shaper constituted of a machine bed provided at its back with a massive upright column having two vertical ways traversed by a saddle. The machine bed has ways on which a second saddle travels, the latter in turn mounting a carriage which supports a turnable table. On the saddle supported by the column there is a swivel head that carries an elongate housing, in which reciprocate a heavy counterweight-type slider and a ram, respectively movable in adjoining parallel paths. The ram, which carries the tool bit, is coupled to the slider by a drive mechanism comprising racks and gears. The slider is driven through a Scotch yoke and set of elliptical gears whereby it has a slow movement in one direction and a rapid movement in the opposite direction. Between the gears and Scotch yoke a shaft extends, disposed on the axis of the swivel head whereby the latter can be adjustably turned without affecting the drive mechanism of the slider and ram. The machine thus has two axes associated with the column, and three axes associated with the bed, making a total of five altogether. The slider, comprising in effect a counterweight, eliminates excessive vibrations at the working speeds.

Description

110d States atent 1 artin 1451 Sept. 11, 1973 FIVE-AXIS SHAPER [76] Inventor: Joseph Martin, c/o Martin Engineering Co. 1nc., 167-17 Northern Blvd., Bayside, NY.

[22] Filed: Apr. 12, 1972 [21] Appl. No.: 243,307

Primary Examiner-Gil Weidenfeld Attorney-11. Gibner Lehmann et a].

57 ABSTRACT A heavy-duty combination vertical and horizontal metal-cutting shaper constituted of a machine bed provided at its back with a massive upright column having two vertical ways traversed by a saddle. The machine bed has ways on which a second saddle travels, the latter in turn mounting a carriage which supports a turnable table. On the saddle supported by the column there is aswivel head that carries an elongate housing, in which reciprocate a heavy counterweight-type slider and a ram, respectively movable in adjoining parallel paths. The ram, which carries the tool bit, is coupled to the slider by a drive mechanism comprising racks and gears. The slider is driven through a Scotch yoke and set of elliptical gears whereby it has a slow movement in one direction and a rapid movement in the opposite direction. Between the gears and Scotch yoke a shaft extends, disposed on the axis of the swivel head whereby the latter can be adjustably turned without affecting the drive mechanism of the slider and ram. The machine thus has two axes associated with the column, and three axes associated with the bed, making a total of five altogether. The slider, comprising in effect a counterweight, eliminates excessive vibrations at the working speeds.

15 Claims, 7 Drawing Figures PATENTEDSEPI H915 5757. 638

' sum 1 0F 4 PATENTEDSEPI 1 I915 575?; 638

- SHEET 3 0F 4 ll FIVE-AXIS siiAPEn BACKGROUND This invention relates to machine tools, and more particularly to tools such as metal cutters, shapers and the like. l-Ieretofore, shapers were restricted as to the various operations that could be performed. Angular cuts were difficult to carry out in many instances, and special shapes often presented a problem. In addition, relatively high speeds produced excessive vibrations, which in heavy equipment, usually were prohibitive. This was particularly true where long working strokes were involved. If irregular shapes had to be cut, prior shapers required changing from one set-up to another, which was also time-consuming. Or, tilting tables were required, which could not be synchronized with the ram movements.

SUMMARY The above disadvantages and drawbacks of prior shapers and metal cutters are obviated by the present invention, which has for its main object the provision of an improved metal-cutting shaper which has avail-' able a total of five axes to perform a large variety of cuts including irregular shapes involving both large and small strokes, and which can operate at relatively high speeds on heavy work and with long strokes, all with a minimum of vibration. This is accomplished by means of a unique machine structure comprising a bed portion and a column portion disposed at the rear of the bed portion, both portions having ways on which saddles are carried. The saddle on the bed mounts a carriage having additional ways which support a rotatable work table. The saddle of the column has a swivel head carrying an elongate housing in which reciprocate a heavy counterweight-type slider and a ram, respectively movable in rear and front parallel paths. Both the slider and the ram are connected by racks and pinions, the ram carrying the cutter tool and the slider being driven through a Scotch yoke and a set of ellipitcal gears whereby it has a fast movement in one direction and a slow movement in the opposite direction. This gives the ram a fast retracting movement and a slow advance or cutting movement. The slider is made to have appreciable mass whereby it functions as a counterweight. By such organization there is had the possibility of both a high operational speed and a minimum of vibration, even for cuts requiring long strokes. The use of a Scotch yoke enables the ram stroke to be smooth and harmonic, and to be readily adjusted. Also, the rack and pinion coupling between the slider and ram permits an advantageous step-up in the speed of the latter while retaining the benefits of counterbalancing and low vibration.

Other features and advantages of the invention reside in an improved shaper and metal cutter as above characterized, which is relatively simple in its elemental, basic design, sturdy and reliable in operatiomeasily setup and used, and especially adaptable to a wide variety of machining operations.

Still other features and advantages will hereinafter appear.

In the accompanying drawings, showing one embodi-, ment of the invention:

FIG. 1 is a perspective view of a metal-cutting shaper as provided by the invention.

FIG. 2 is a diagrammatic representation of the essential, novel working parts of the shaper.

FIG. 3 is a vertical section through the upper portion of the machine, taken on the line 3-3 of FIG. 1.

FIG. 4 is a rear plan view of the slider and Scotch yoke assembly of FIG. 3.

FIG. 5 is a vertical section through the upper portion of the machine, taken on the line 5-5 of FIG. 3.

FIG. 6 is a vertical section, taken on the line 66 of FIG. 1.

FIG. 7 is a fragmentary perspective view of the shaper of the present invention, illustrating a tilted or angular adjustment of the reciprocatable ram and the housing carrying the same.

Referring first to FIG. l, the shaper shown therein comprises a bed or base portion 10 on which there is mounted at the rear an upright portion or column 12. The base and column portions can be cast of iron or steel, or else they can be fabricated of heavy structural shapes which are welded together to obtain the desired configuration or structure. The base portion 10 mounts a saddle 14 having forward and rearward extending ways 16 on which there is carried a carriage 18. Ways 20 on the carriage l8 mount an adjustable carrier member 22. With such arrangement the carriage 18 can be shifted forward or backward along the base 16 by suitable servo motors, and the carrier 22 can be shifted to the right or to the left on the carriage 18 along the ways 20 of the latter, this being effected by well-known servo motors.

In accordance with the invention there is secured to the carrier member 22 a rotary table 24 which is rotatably adjustable on the carrier and can be power fed or positioned by well-known servo motors carried or mounted in the carrier 22. Thus three working axes are provided on the base portion 10, one axis extending forward and rearward, the second extending from right to left, or vice versa, and the third axis being the center of rotation of the powered table 24.

On the column portion 12 vertical ways 26 are provided, along which there is vertically shiftable a saddle 28, hereinafter also referred to as a ram saddle. The ram saddle 28 when not locked in a give raised or lowered position, can be positioned in either feed mode or power mode, being adjusted by power, through a suitable mechanism which can comprise either a powered screw and nut, or else a hydraulic piston device (not shown). The ram saddle can have a servo device, for example. Powered devices for raising or lowering a ram saddle in a machine tool are well known in the art. This can also be a servo drive.

In accordance with the present invention there is mounted on the ram saddle 28 a rotary or swivel head 30 which carries an elongate ram housing 32 rigidly affixed thereto. The swivel head 30 is rotatably adjustable when swivel clamps 34 are loosened (one of which is seen in FIG. 1). Upon the desired rotative position of the swivel head 30 and ram housing 32 being attained, the swivel clamps 34 are tightened to lock the head in the desired rotary position. A. scale and index marks:

(not shown) on the swivel head 30 and ram saddle 28 enable the operator to position the head at any desired angle as required by the nature of the work being cut. The swivel head 30 can also be put into a feed mode, as will be understood.

By the present invention there is provided, carried by the ram housing 32 a dynamically balanced comination ram and slider which effectively overcomes vibrations when performing operations on a workpiece at relatively high speeds and with long strokes. This combination mechanism comprises, in conjunction with a ram 36 which is longitudinally reciprocatable in the ram housing 32, a slider or counterweight 38 which is also reciprocatably and longitudinally movable in said housing. The ram and slider parts travel in paths which are spaced from and parallel to each other, and are interconnected by a drive mechanism to effect opposite movements of said parts in response to their being driven. According to the invention the interconnecting means comprises a pair of ram racks 40 which mesh with spaced apart gears 42 affixed to a spindle 44. The spindle 44 also carries a third gear 46 of smaller diameter than the gears 42 but rigid therewith, the gear 46 meshing with a rack 48 carried by the slider 38. In FIG. 2, the rack and gear drive mechanism is shown diagrammatically, there being but a single gear 42 and rack 40. However, it will be understood that such diagrammatic showing is made for purposes of simplifying the understanding of the invention, whereas the acutal arrangement of the rack and pinion drive mechanism is more accurately illustrated in FIGS. 3 and 5. The shaft 44 for the

gears

42 and 46 extends through the sides of the ram housing 32 and can be seen in FIG. 1.

By virtue of the gear 46 having a smaller diameter than the gears 42 there is had a mechanical step-up of the movement of the ram 36 as compared with the slider 38. For example, the ram 36 can have a 22 inches stroke with the slider 38 having a l7 inches stroke.

Application of power is made to the slider 38, according to the invention, and the said slider is made to have a significant or appreciable weight whereby it constitutes in effect a counterbalance or counterweight, thereby to greatly lessen vibration and unbalance when operations are being performed with a long stroke and at high speed on workpieces. l have found that by making the slider with a dynamically balanced mass a desirable advantage is had in much smoother operation and in effecting an extended capability of the machine, particularly when considering large strokes and high speeds.

In accordance with the present invention driving power is applied to the slider 38 by means of a Scotch yoke. Referring to FIG. 2, the slider 38 is provided with a crosshead or slotted Scotch yoke portion 50 having a groove 52 in which there is accommodated a roller 54 on a crank pin 56, the latter being carried by a block 58 which is adjustable along the length of a powerdriven yoke arm 60. The yoke arm 60 is carried by a shaft 62 to which there is affixed an ellipitcal gear 64 meshing with a cooperable ellipitcal gear 66 secured to a shaft 68. The shaft 68 is driven through

gears

70, 72, the latter being on a shaft 74 carrying a worm wheel 76 which meshes with a worm 78. The worm 78 is on a shaft 80 which has a gear wheel 82 meshing with a cooperable gear 84, the latter being on a shaft 86 which is driven through

pulleys

88, 90 and a belt 92 from a variable speed d.c. motor 94. The power system comprising the

elliptical gears

64, 66 on through to the motor 94 is preferably contained in the upright column 12. The transmission shaft 62 is at the axis of the swivel head 30, thereby enabling such head to be rotatably adjustable about the shaft without conflicting with the power drive from the motor 94 all the way through to the slider or counterweight 38. As previously stated,

the slider 38, ram 36 and interconnecting drive mechanism are carried by the ram housing 32. The ram 36 has a clapper box 96 provided with a bit hole or socket 98, which is a usual construction.

The above described power drive means and especially the elliptical gearing is so arranged that the down or working stroke of the ram 36 is characterized by a relatively slow movement, whereas the retracting or upward stroke of the ram 56 is efiected at a much more rapid pace, all as made possible by the

gears

64, 66, and this is an important feature of the invention. Such elliptical gears in conjunction with the combination sliderram and interconnecting drive mechanism enables a high rate of production to be had due to increased cutting speeds and long working strokes, all with a minimum of vibration.

Referring to FIG. 6, the yoke arm 60 has a slide means comprising a longitudinal groove 100 in which the block 58 can be adjusted. To effect this, the block has a threaded bore 102 in which there is disposed an elongate adjusting screw 104 extending longitudinally in the groove 100. The adjusting screw 104 has a head 106 adapted to accommodate a tool such as a socket wrench or the like. The swivel housing 30 has an access opening 108 to accommodate such tool for the purpose of turning the adjusting screw 106. By such arrangement the block 58 can be shifted to various adjusted positions on the yoke arm 60, thereby either increasing or decreasing the effective stroke of the arm and consequently the diameter of the path of travel of the crank pin 56. Therefore, the extent of movement or reciprocation of the slider 38 can be varied from an extremely short stroke to a relatively long stroke. Regardless of the extent of the stroke, the mass of the slider constitutes an effective counterbalance or counterweight, thereby to minimize to a maximum extent any vibrations which would otherwise occur in the absence of the slider, particularly when the machine is operated at high production speeds and with a long working stroke.

The rotary adjusting of the swivel head 30 can be effected by a worm 110 meshing with the cooperable worm gear segment 112 disposed within the swivel head 30. The worm 110 can be carried on a shaft 114 which can receive power from a suitable source (not shown) located in the upright column 12 of the machine.

As previously mentioned, the table 24, carriage 18 and carrier 22 represent three working axes of the machine. The fourth working axes is represented by the vertical ways 26 of the upright column 12, enabling the assemblage of swivel head, ram housing and ram to be raised and lowered. The fifth effective working axis comprises the path of travel of the ram 36 in the ram housing, such path of travel being either perfectly verti' cal or else at an angle as illustrated in FIG. 7.

The improved machine of the present invention lends itself readily to programmed operation, as for example by being run from punched paper tape. Thus it is possible' to program and generate many new shapes that v were previously not possible to produce onordinary shapers. Servo-motors can be used in connection with all five axes, whereby the machine is compatible for computerized operation. lt is to be noted that an electrical signal can be generated by the ram each time it reaches the top of its stroke. This signal can then be used to feed any one axis, or any combination of axes, a selected amount. For instance, all five axes can be fed simultaneously, if desired. The feed of the five axes (or a fewer number) can be a function of the feed of one axis. Various mathematical combinations are also possible. Thus, automatic operation involving complex shapes is readily obtainable.

It will now be seen from the foregoing that l have provided a novel and improved metal cutting shaper or machine tool which is extremely versatile in use in that five working axes are available. Further, the machine tool can have a high rate of production due to increased speeds and long working strokes, all without undue vibration which heretofore characterized prior machine tool of this type. The elimination of vibration has been accomplished by the provision of the slider or counterweight to which the power is applied and thence transferred to the ram and cutting bit. The relatively high retraction speed and slow working movement of the cutting bit is accomplished by the use of the elliptical gears in the power transmission, andthe additional working axes are made possible by the swivel mounting of the ram housing, comprising the swivel head 30. The mechanical movements involved are seen to be straightforward and relatively simple, and adequate strength is had for performing heavy machining operations without the likelihood of failure. Electronic control of the various movements of the machine parts along the respective axes provided for precision'machining and exact duplication of parts.

Variations and modifications are possible without departing from the spirit of the invention.

1 claim:

1. A machine tool for performing cutting or shaping operations on a workpiece, comprising in combination:

a. a column having upstanding ways,

b. a saddle carried by the column and movable along the ways thereof,

0. a swivel head on the saddle, said head being turnably adjustable thereon,

d. a slider reciprocatable on the swivel head,

e. powered drive means connected to the slider for reciprocating the latter,

f. a ram having means for mounting a tool bit, said ram being reciprocatable on the swivel head in a path spaced from and parallel to the path of movement of the slider, and

g. a drive mechanism interconnecting the slider and ram for effecting movement of the latter in directions opposite to those of the slider,

h. said slider having a significant and appreciable mass whereby it constitutes a dynamic counterweight with respect to the ram.

2. A machine tool as in claim 1, wherein:

a. said powered drive means comprises a pair of meshed elliptical gears for effecting a slow movement of the slider in one direction, accompanied by advance of the ram, and for effecting a fast movement of the slider in the opposite direction, accompanied by retraction of the ram.

3. A machine tool as in claim 1, wherein:

a. said powered drive means comprises a Scotch yoke connected to said slider and a yoke arm engaged with said Scotch yoke.

4. A machine tool as in claim 3 and further including:

a. means for effecting an adjustment of the effective length of said yoke arm.

5. A machine tool as in claim 1, wherein:

a. said powered drive means comprises a pair of meshed elliptical gears for effecting a slow movement of the slider in one direction, accompanied by advance of the ram, and for effecting a fast movement of the slider in the opposite direction, accompabied by retraction of the ram,

b. said drive means further including a Scotch yoke connected to the slider, and a yoke am engaged with said Scotch yoke,

c. said yoke arm being driven from said elliptical gears.

6. A machine tool as in claim 5 and further including:

a. a shaft on which the yoke arm is carried,

b. said swivel head having the same axis as said shaft.

7. A machine tool as in claim 3, wherein:

a. the swivel head has an axis which coincides with the axis of said yoke arm.

8. A machine tool as in claim 2 and further including:

a. a ram housing enclosing said slider and drive mechanism,

b. said elliptical gears being contained in said column.

9. A machine tool as in claim 1 and further including:

a. a ram housing in which the slider and drive mehcanism are disposed,

b. said Scotch yoke being carried by the bottom end of the slider and being disposed in said ram housmg.

10. A machine tool as in claim 1, wherein:

a. said drive mechanism comprises a pair of racks disposed respectively on the slider and ram, and com prises gearing engaged with said racks.

11. A machine tool as in claim 10, wherein;

a. the said gearing comprises a pair of gears of different diameters,

b. the gear of smaller diameter being engaged with the rack carried by the slider, thereby to effect a step-up gear ratio from the slider to the ram.

12. A machine tool as in claim 1, wherein:

a. said drive mechanism comprises a pair of racks disposed respectively on the slider and ram, and comprises gearing engaged with said racks,

b. said powered drive means comprising a pair of meshed elliptical gears for effecting a slow movement of the slider in one direction, accompanied by advance of the ram, and for effecting a fast movement of the slider in the opposite direction, accompanied by retraction of the ram.

13. A machine tool as in claim 4, wherein:

a. said yoke arm has an elongate groove,

b. said adjustment means comprising a block slidably along said groove and having a roller engaged with the Scotch yoke, and comprising screw means for adjustably positioning the block on the yoke arm along the groove thereof.

14. A machine tool as in claim 13, wherein:

a. the yoke arm is disposed within the swivel head,

b. said head having an access opening through which the screw means can be reached.

15. A machine tool as in claim 11 and further includa. an additional rack on the slider, and b. an additional gear rigid with said pair of gears and engaged with said additional rack.

Claims

1. A machine tool for performing cutting or shaping operations on a workpiece, comprising in combination: a. a column having upstanding ways, b. a saddle carried by the column and movable along the ways thereof, c. a swivel head on the saddle, said head being turnably adjustable thereon, d. a slider reciprocatable on the swivel head, e. powered drive means connected to the slider for reciprocating the latter, f. a ram having means for mounting a tool bit, said ram being reciprocatable on the swivel head in a path spaced from and parallel to the path of movement of the slider, and g. a drive mechanism interconnecting the slider and ram for effecting movement of the latter in directions opposite to those of the slider, h. said slider having a significant and appreciable mass whereby it constitutes a dynamic counterweight with respect to the ram.

2. A machine tool as in claim 1, wherein: a. said powered drive means comprises a pair of meshed elliptical gears for effecting a slow movement of the slider in one direction, accompanied by advance of the ram, and for effecting a fast movement of the slider in the opposite direction, accompanied by retraction of the ram.

3. A machine tool as in claim 1, wherein: a. said powered drive means comprises a Scotch yoke connected to said slider and a yoke arm engaged with said Scotch yoke.

4. A machine tool as in claim 3 and further including: a. means for effecting an adjustment of the effective length of said yoke arm.

5. A machine tool as in claim 1, wherein: a. said powered drive means comprises a pair of meshed elliptical gears for effecting a slow movement of the slider in one direction, accompanied by advance of the ram, and for effecting a fast movement of the slider in the opposite direction, accompabied by retraction of the ram, b. said drive means further including a Scotch yoke connected to the slider, and a yoke arm engaged with said Scotch yoke, c. said yoke arm being driven from said elliptical gears.

6. A machine tool as in claim 5 and further including: a. a shaft on which the yoke arm is carried, b. said swivel head having the same axis as said shaft.

7. A machine tool as in claim 3, wherein: a. the swivel head has an axis which coincides with the axis of said yoke arm.

8. A machine tool as in claim 2 and further including: a. a ram housing enclosing said slider and drive mechanism, b. said elliptical gears being contained in said column.

9. A machine tool as in claim 1 and further including: a. a ram housing in which the slider and drive mehcanism are disposed, b. said Scotch yoke being carried by the bottom end of the slider and being disposed in said ram housing.

10. A machine tool as in claim 1, wherein: a. said drive mechanism comprises a pair of racks disposed respectively on the slider and ram, and comprises gearing engaged with said racks.

11. A machine tool as in claim 10, whereIn; a. the said gearing comprises a pair of gears of different diameters, b. the gear of smaller diameter being engaged with the rack carried by the slider, thereby to effect a step-up gear ratio from the slider to the ram.

12. A machine tool as in claim 1, wherein: a. said drive mechanism comprises a pair of racks disposed respectively on the slider and ram, and comprises gearing engaged with said racks, b. said powered drive means comprising a pair of meshed elliptical gears for effecting a slow movement of the slider in one direction, accompanied by advance of the ram, and for effecting a fast movement of the slider in the opposite direction, accompanied by retraction of the ram.

13. A machine tool as in claim 4, wherein: a. said yoke arm has an elongate groove, b. said adjustment means comprising a block slidably along said groove and having a roller engaged with the Scotch yoke, and comprising screw means for adjustably positioning the block on the yoke arm along the groove thereof.

14. A machine tool as in claim 13, wherein: a. the yoke arm is disposed within the swivel head, b. said head having an access opening through which the screw means can be reached.

15. A machine tool as in claim 11 and further including: a. an additional rack on the slider, and b. an additional gear rigid with said pair of gears and engaged with said additional rack.