US1563310A - Cylindrical-grinding machine - Google Patents

Description

Nov. 24, 1925.

C. H. NORTON CYLINDRIGAL GRINDING MACHINE Original Filed Jan. 29, 1921 2 Sheets-Sheet 1 as a3 a gharles H. NorTon Nov. 24, 1925.

C. H. NORTON CYLINDRICAL GRINDING MACHINE Original Filed Jan. 29, 1921 2 Sheets-Sheet 2 Charles H. NorTon for the grindin of such articles as the Patented Nov. 24, 1925.

UNITED STATES CHARLES H; NORTON, orrnamvnnn, cormnc'rrcur,

ASBIGNOR '10. NORTON COI- ?ANY, OF WORCESTER, MASSACHUSETTS, A CORPORATION OF MASSACHUSETTS.-

CYLINDEICAL-GRINDING MACHINE.

Application filed January 29, 1921, Serial No. 441,047; Renewed October 18, 1924.

To all whom it may concern:

Be it known that'I, CHARLES 'H. N ORTON, a citizen of the United States of America, residing at Plainville in the county of Hartford and State of Connecticut, have invented certain new and useful Improvements in Cylindrical-Grinding Machines, of which the following is a -full, clear, and exact specification.

My invention relates to a machine for grinding cylindrical objects and more par.- ticularly to a double head machine having driven work-supporting spindles adapted PIIIS and bearin s o crankshafts. 1

The finisliing of crankshaft pins and bearings, because of the high degree of accuracy and finish demanded, is now usually done on a grinding machine. In order to avoid torsional strains in the work during the grinding operation, it is advisable to drive the workv positively from both ends,. instead of having it driven from one end alone as in grindin straight cylindrical pieces. en grin ing the pins of crankshafts, it becomes necessary tosupport the shaft ec-.' centrically of the axis of rotation of the driving spindles in special holding devices, this eccentricity varying with the throw of the crank. It is also highly important that f the work be held rigidly and that the axes and maintained in such alignment aligned or a long eriod of time, so that, whenthe work is finls hed, the axes of the pins will be parallel for pins angularly disposed relative to each other or in alignment for pins on the same of the drivingspindles be accuratelfy side'of the shaft. It will be apparent that a machine having a any sli ht deviation from accurate alignment 0 the axes of the work driving spine precisely synchronized drive for said spindles will result in imperfections in the work. Since the permissible error in this kind of work is very small, the elimination of such factors becomes highly important.

It is therefore one object of my invention to overcome these difliculties by roviding massive wor -holding table of ri id construction in which the spindles of t e work heads are supported on bearing surfaces rigid with the table so that their axes are aligned with each other and steadily held in such aligned relation, and arrangcdin parallelism with the table through the left-han ways, whereby tables of may be readily intercha grinding operations. To t is end I provide a table having work head members rigid and integral with the table,.said members having aligning surfaces, which may be and preferably are V-shaped in cross section, ada ted different lengths ed for different to receive bearing blocks having sur aces or adjusting them with relation to the spindle.

- It is a further object of my invention to provide eflicient and positive driving connections from a shaft on the base of the machine to the two spindles in the work heads, whereby the balance of the s indles is assured and they are driven synchronously, providing an even wear of the bearings and the elimination of torsional strain in the work during the grinding operation.

It is a still further object of my invention to rovide an oiling system in connection wit my spindle bearings that is highly ef ficient in operation and assures an even distribution and a constant sup 1y of.oil between the spindle and its cy indrical bearing member.

lVith these and other objects in view, as will appear from the following disclosure, my invention resides in the combination of parts set forth in the specification and covered by the claims appended thereto.

In the drawings in which like reference numerals indicate likeparts:

- Figure 1 is a front elevation of a grinding machine embodying my improvements, parts being shown in section or broken away to show the driving connections to the work heads;

' Fig. 2 is an enlar ed transverse section (f work head, the table, and a part of the base;

Fig. 3 is an enlarged vertical section through the work head and part'of the driving connection thereto, a part of the spindle and its bearing block being shown in elevation;

Fig. 4 is a partial section through the gear the spindles the work table, showing the integral work head members;

Fig. -7 is an enlarged perspective view showing a lower bearing block and its opposed adjustable blocks; and

Fig. 8 is a sectional view similar to Fig. 2

showing a modification of the spindle bear- In the embodiment of my invention selected for illustration, I have shown a slide, such as the work table 10, having parallel ways 11 mounted to slide on the parallel ways 12 of any suitable form of base 13, said slide or table being provided with means for moving it on the ways, such as the usual rack 14 attached to the under side of the table and meshing with a pinion 15 on a transverse shaft 16 driven as from the hand wheel 17 through intermediate gearing 18. In Fig. l I have shown the grinding wheel IV, which is mounted on a cross slide in the usual way, in operative relation to the work X.

The table 10, which has a massive rigid construction, as will be apparent from an inspection of Fig. 6, is provided at its ends with rigidly and integrally formed worksupporting members 19 having surfaces 20 for receiving the bearing blocks 21, said surfaces being made inv accurate axial alignment with each other, as by planing and scraping the parts, and'arranged in parallelism with the table Ways. These aligned surfaces thus form reference surfaces, both initially and after the original bearing blocks become worn so as to require replacement, for accurately aligning the partial cylindrical surfaces 23 of said blocks and hence the axes of spindles 24 which are received in said blocks. The surfaces 20 are preferably V-surfaces, as shown, the angle formed by the V being substantially a right angle. The V-shaped aligning surfaces are cut away in intermediate portions, as at the points 25 and 26, to lessen the cost of scrap mg, it being noted that various shapes equivalent to that shown in the drawing may be known as V-shaped. Thebearing blocks 21 having on their upper sides the partial cylindrical surfaces 23 to receive the spindles are formed on their under sides with V-surfaces 27 mating the V-surfaces 20, so as to accurately fit the same. By grinding or planing these blocks in pairs on an arbor, the V-surfaces 27 can be made to contact with the V-surfaces 20 at all points not cut away, and the axes of the surfaces 23 will be accurately aligned, thus assuring the similar alignment of the work spindles 24. The blocks may be drawn tightly against the V-surfaces 20 by means of screws 30 (Fig. 2).

To hold the s indles in correct relation with the lower aring blocks 21 and to prevent jumping or vibrating, I may employ any suitable means, but I have shown a pair of upper bearing blocks 31 for each lower block, one of said upper blocks bein arranged adjacent each end of the spindle. The upper sides of the spindles are enclosed in partial. cylindrical casings or caps 32 which are fastened to the work head members integrally formed with the table 10 by the screw bolts 33. The bearing blocks 31 are located between these casings and the spindles and may be adjusted toward the spindles by means of screw bolts 34 provided with knurled heads 35 and the usual lock nuts 36. These screwbolts 34 form preci sion means for adjusting the bearin blocks and their knurled heads are of sue a size that the operator cannot manuall set the bearing blocks against the spin les with sufficient pressure to crush out the oil film.

It is highly important in grinding the pins of crankshafts, for example, that the work holders be accurately aligned when the work is clamped thereto to prevent any twisting or distortion of the shaft which would result in imperfections in the finished work, and for a like reason it is important that the two work-drivin spindles be driven in precise synchronlsm. I obtain such a drive by mounting a gear 37 on the outer end'of each spindle 24 and driving these ears by any suitable means such as from t e shaft 38 which is mounted adjacent its ends in bearing brackets 41 connected to the table as by screws 42. To make the machine self-contained, this shaft is preferably driven through a gear 43 arranged between its ends, said gear being splined the eto to allow relative sliding movement etween it and the shaft, the shaft being supported on opposite sides of this gear by a suitable bearing bracket 39 connected to the base. The drive shaft 44 mounted in the base of the machine (see Fig. 1) is in turn driven by any suitable means such as drivin connections from a motor (not shown? on the back of the machine. These gearsare preferably sprocket gears driven by chains. The shaft 38 on the table is driven from a sprocket gear 45 on shaft 44 in the base by means of a chain 46 and the Hill shaft 38 drives through sprocket gears 47 j dies 24 and the sprocket substantiall cup-shape rotation between the formed with a reduced squared head to receive a wrench or other tool for rotating it, and, inwardly of this s uared head, it is formed with a screw three to receive a nut 58 thereon for drawing the bracket and cap in close frictionalcontact, whereby the idler will be held in adjusted position.

The spindles are provided at their inner ends with the usual plates (SO-for fastening the work holders 61 to which the work X is clamped in the usual manner. To secure a fine rotary adjustment-between the spinears 3'] for precisely aligning the work 0 amping means, I may mount at least-one of the sprockets 37 in the manner shown in Fi s. 3 and 4. have there shown the s roe et 37 as being to fit over the end of the spin le and connected thereto by bolts 62. The bolts extend through arcuate slots 63 in the sprocket to allow limited relative sprocket and. the spindle. -O n-diametrically opposed sides of the sprocket '-I rovide enlarged openings 64 having bevelled sides. openings receive screw bolts 65 which screw into the ends of the spindle and have bevelled portions'fitl'thereon for cooperation with the bevelled sides of ;the openings 64. These bolts are both arranged at one side of a vertical lane assii g through the axis of the 'upperbolt the sprocket is rotated by the spind e, wh e the centers of the openings 64 are arranged in this lane and bothbolts are normally screwed}, own until their bevels engage the bevelsiofthe openings. Then it iscsiredto adjust the sprocket on the shaft, let us say in a clockwise direction, Fig. 4, the bolts 62 are loosened and the lower bolt 65 is likewise unscrewed. so as to back off its bevelled surface from the bevelled surface.

in the opening 64, and by tightening the c agement of the bevelled surfaces on the hot and its cooperating opening. until the bevelled surfaceson the. lower bolt and its cooperatingopening1 are again in enga ement. To take up t e end thrust, I provide the spindles 24'w1th collars engaging the bearing blocks 21'at oneiend thereof and nuts 71 held in placetby suitable locknuts 72 at the opposite ends. 4 1

Another feature of my invention fcomprises an eflicient oiling system which in sures a copious supply of oil between the spindles and their hearing bushings. This may comprise an oil well 73 arranged at substantiall the central portion of the work headbc ow the work spindle and o cmng upward into the spindlebearings. prcfcrably convey the oil. out of this well by means of a chain 74 passing through slots 75 in the bearing blocks and around the spindles. Channels are rovided in the upper edges of the bearing locks 21, these channels iaving their bottoms slopingaway from the slots 75 to the ends of the bushingsv and towards the spindle so that as the oil is carried by the chain in the revolutionoi'the s indie to the top of the spindle, some of it ows into these channels and along them in contact with the spindle, any sur lu s oil findingits way to the ends of the bushing where it drops by gravity or'is thrown off by centrifugal force from the collars and the nuts 71 and 72 and. is caught by. the oil uards 76 and 77, from whence it is returned y gravity through the sloping channels 78 and 79 to the well 73. v

An advantageous feature of my invention relates to the interchangeability of work tables. This is of considerable importance from the point of view of the user of such 7 a machine having several diflerent lengths of crankshafts to grind and yet not having sufficient of such work to warrant having two machines. The ways of the tables and the base being scraped to standard bars, it'- willbe obvious that different tables will fit the same base and a user of this machine will be enabled to grind different lengths of. work if equipped with a single machine having interchangeable tables of different. lengths. For small differences in the lengths of the crankshafts, say several inches, it may be unnecessary to use different sized tables such accommodation being obtained by substituting different work holders. Where .the

difference in length is greater, this method of adjusting the machine tothe work would i I 10:)

not be as desirable as the interchangeable tables.

In Fig. 8,-I have shown a modified construction of the spindle bearings shown in.

Figs. 2 and 3, whichmay be advantageously employed in certain grinding operations, because it permits of a very line lateral pollO sitioning of the spindle in its bearings. I I there employ adjacent each end of a spindle two upper bearing blocks 81 similar to the 85, similar to the caps 32, except as shown modifiedin Fig. 8, to adapt it to receive two upper bearing blocks. M oiling system insures a copious supplyo oil to the. spindle and bearings, so that, during the normal operation of the machine, there always exists a thin film of oil between the spindle and the hearings in which it rests, which is only a fraction of a thousandth of an inch in thickness. Because of this fact, I am enabled to bring greater pressure to bear on the upper bearing blocks 81 arranged on one side of the spindle than on those arranged on the opposite side by a proper manipulation of the adjusting screws 82, and thus move the spindle in the direction of the greater thrust a fraction of a thousandth of an inch'by forcin out some of the oil film between it and tie bearing block 21 on that side of the spindle opposite the side receiving the greater thrust.

It is obvious that changes may be made in the specific construction of my device and that equivalent elements may be substituted for the arts herein disclosed without departing romthe scope of my invention as ex ressed in the claims appended hereto.

aving thus described my invention, what I claimas new and desireto secure by Letters Patent is:

1. A double head grinding machine comprising a base having parallel ways thereon, a 'slidable work table having ways mating with the base ways, work head members integral with said table, spindle bearings thereon having bearing surfaces in precise axial alignment, and work-supporting spindles mounted on said surfaces and aligned thereby.

2. A double. head grinding machine comprising a base having parallel ways thereon, a work table slidably mounted on said ways, integral work head members on opposite ends of said table, lower spindle bearings thereon having cylindrical surfaces in accurate axial alignment, work-supporting spindles mounted on said surfaces and aligned thereb and fine precision means to hold the spind es in correct relation with the lower bearing surfaces.

3. A grinding machine comprising a base having parallel ways thereon, a slide [HOV-81'. bly mounted on said ways, spindle suppor ing members integral with the slide and hav-. ing aligning V-surfacesand bearing blocks having V-surfaces mating with said aligning surfaces and rigidly fixed thereon, said blocks having spindle bearing surfaces axially parallel with said aligned surfaces of .the slide.

4. A grinding machine comprising a base having parallel ways thereon. a work table slidably mounted on said ways, a work head member integral with said table and having a V-surface arranged in arallelism with the table ways, a bearing b oek having a V- surface matin with the V-surface on said member, said aring block having a cylindrical bearin surface axially parallel with and on the si e opposite the V-surface theresaid cylindrical bearing surface and adjustable means for holding said spindle in correct relation with said bearing block.

5. A double head grinding machine comprising a base having parallel ways thereon, a slidable work table having ways mating with the base ways, work head members integral with the table and having aligning V-surfaces parallel to the table ways, work supporting s indle blocks having lower V- surfaces mating with said aligning surfaces and upper cylindrical surfaces for the spindles, said blocks being rigidly mounted on said members, whereby the spindle axes traverse in a stralght line.

6. A double head grinding machine comprising a base having parallel ways thereon, a work table slidably mounted on said ways,

lower bearing members rigidly fixed on said 7 table in axial alignment and spaced relationship, spindles mounted in said bearings," supporting members rigidly fixed to said table and extending above said spindles, upper floating bearing blocks engaging said spindles, and means cooperating with said supporting members to position said floating bearing blocks accurately with relation to the spindles.

7. A double head grinding machine comprising a base having parallel ways thereon, a work table slidably mounted on said ways and having work-supporting portions on its ends provided with V-shaped aligning surfaces, lower spindle bearing blocks having V-shaped surfaces mating'with said aligned surfaces and rigidly mounted on said table portions, said bearing blocks having cylindrical surfaces in axial alignment, spindles mounted therein, and upper adjustable hearing blocks mounted on the table for engagement with the spindles to hold the same firmly against the cylindrical surfaces.

8. A double head grinding machine comprising a base having a Vway and an as soeiated way parallel thereto, a work table having ways on its under surface mating the ways on said base, said table having align.- ing V-surfaces ad'acent its opposite ends arallel with sai V-way, lower bearing locks havin V-surfaces mating with the V-surfaces o the table, said blocks being rigidly fastened .to said table, each block having an upper cylindrical surface, the axis of which is parallel with the lower-V-surfaces of the blocks, spindles mounted in said bearing blocks in axial alignment, a casing mounted over said spindles, adjustable upper bearing blocks mounted in said casing and means cooperating with said blocks and casing to hold the upper blocks in accurate contact with the spindles.

9. A grinding machine comprising a slidable work table,'work heads integral with said table,

Ill)

spindles.

10. A grinding machine comprising a base, ways on said base, a work table slidably mounted on saidways, rigid work heads arranged adjacent the ends of said table, bearing surfaces in fixed axial alignment on said work heads, work-driving spin dles supported in said bearings, a shaft mounted on said slidable work table, chain driving.connections between said-shaft andthe work-driving spindles, a fixed drive shaft in the base of the "machine, and chain and the movable shaft.

11. A grinding machine comprising a base having ways, a slidable work table having ways mating the ways on the base, a spin,

dle bearing block -rigidly fixed on said table,

and axially parallel with the table ways, a work-supporting spindle mounted on said bearingblock, driving means for said spindle arranged adjacent one endthereof and exerting a downward pull on the spindle, and .a relatively massive work holder at the other end thereof, the pull exerted by said driving means and the weight of the work holder and work substantially balancing each other, whereby the bearing block will be evenly worn. I

12, A grinding machine com rising a base having ways, a work table s idable on said ways, work supporting heads integral with the table, V-shaped surfaces on the heads in precise alignment, lower bearing members having V-shaped surfaces mating with said surfaces on the'heads, rigid connections between the heads and members, partial cylindrical surfaces on said members, spindles mounted on said members in fixed axial. alignment and upper adjustable hearing blocks to hold the spindles in position relative to the members.

13. A grinding machine comprising a base havingstandard parallel ways, a sliding work table forming one of a set which hasways mating with the standard base ways, work head members integral with said table, and work-supporting spindles mounted on said members in fixed axial alignment, whereby the table selected serves as a for supporting work of the particular size being treated. 14. A grinding machine comprising a base, ways on said base, a work table slidably mounted on said base ways, work head members integral with and arranged adjacent the opposite ends of said table, lower spindle-supporting blocks thereon having cylindrical bearing surfaces normally in axial alignment, work-support1ng spindles mounted on said surfaces, and means comprising finely adjustable bearing blocks to old the spindles in proper relations with the supporting blocks and in precise alignment. J

1 5. A grinding machine comprising a base having ways, a work table slidably mounted on said ways, work head members rigid with said table, lower spindle-supporting blocks carried bysaid members and having cylindrical bearing surfaces, work drivingand supporting spindles mounted on said surfaces, and means comprising finely ustable bearingblocks arranged on opposite sides of a plane passing approximately tliroughtlie spindle axes to. position and the supporting blocks ant in precise alignment.

16. A grinding machine comprising a .holdthe spindles in pro. er relations with" (ll'lVIIlg connections between said fixed shaft base l1aving' parallel ways thereon, a work table slidably mounted on said ways, a work head member on said table which has a V surface arranged in parallelism with the table ways, a bearing block having a V surface mating with the V surface on said, member, and a work supporting spindle mounted on said block. v

' '17. A grinding machine comprising a base having parallel ways thereon, a work table slidablymounted on said ways, a work head member integral with said table which has an upper V surface parallel with the table ways, a bearing block having a lower surface mating with said V surface and means for holding a work supporting spindlewon said block.

18. A grinding machine comprising a base havin parallel ways thereon, a work table slidab y mounted on said ways, a work head member integral with said table, a bearing block thereon, saidmember and bearing block having interfittingaligning surfaces arallel with said table ways, sa1d bearing llloek havin a cylindrical bearing surface axially para lel with said aligning surfaces, and a work supportingspindle mounted on said block.

19. A grinding machine comprising a base, a work table on said base, two .work

vheads mounted thereon, workdriving spindles mounted on said heads in axial ahgn-- I menti'a driving. shaft parallel. with said s m s aft to each of the spindles, and means to synchronize the spindles.

20. A grinding machine comprising a base, a work table slidably mounted on said base, two work heads mounted thereon, work driving spindles mounted on said heads'in axial aligmnent, a driving shaft parallelwith said s indies and driving connections from said s aft to each of the spindles, a driving member on each spindle, means 0on necting said shaft with each member to roles and driving connections from said spindles, driving connections between'said aft and ears, and means to rotatively adjust one 0 said gears relative to the spindle to synchronize said work holders.

22. A grinding machine comprising a base, a work table slidably mounted on said base, two work heads mounted thereon, work driving spindles mounted on said heads in axial alignment, offset work holders on said spindles, a driving shaft parallel with said spindles, a gear mounted on each of said s indles, driving connections between said s aft and gears, means comprising screws having conical portions cooperating with conical apertures in one of said gears to rotatively ad'ust said lgear relative to the spindle to sync ronize t e work holders.

, 23. A grinding machine comprising a support for the work, a work head member on said support which has a V surface arranged I in parallelism with the axis of work, a bearing block having a lower V surface mating with the V surface on said member, and an upper partial cylindrical bearing surface an a work supporting spindle mounted on the upper bearing.

A rinding machine comprising. a support for the work, spindle supporting members integral with the support and having aligning V-surfaces and bearing blocks having V-surfaces mating with said aligning surfaces and rigidly fixed thereon, said blocks having s indle bearing surfaces axially parallel w1th said aligned surfaces of the spindle supporting members.

Signed at WVorcester, Massachusetts, this 28th day of J an., 1921.

' CHARLES H. NORTON.

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