US2520822A - Infeed attachment for centerless grinding machines - Google Patents

Description

K. ANDERSON Aug. 29, 1950 INFEED ATTACHMENT FOR CENTERLESS GRINDING MACHINES Filed Feb. 26, 1949 4 Sheets-Sheet 1 IN VEN TOR.

KEITH ,INDf/RSON.

ATTORNEY.

Aug. 29, 1950 H K. ANDERSON 2,520,822

INFEED ATTACHMENT FOR CENTERLESS GRINDING MACHINES Filed Feb. 26, 1949 4 Sheets-Sheet 2 INVENTOR. KE/i'f/ ANDERSON. I

Patented Aug. 29, 1950 INFEED ATTACHMENT FGR CENTERLESS GRINDING MACHINES Keith Anderson, Highland Park, Mich.

Application February 26, 1949, Serial No. 78,645

6 Claims. (01. 51-103) This invention relates to centerless grinding machines and more particularly to mechanism for controlling and Operating the in and out feeding of the carriage which carries the regulating wheel relative to the work piece.

It is the principal object of this invention to provide an infeed attachment for the centerless grinding machine whereby said in and out feeding movements of the carriage are effected automatically.

, It is the further object of this inventionto provide an infeed nut threadably mounted upon the carriage lead screw for reciprocal rotary movements thereon, said nut being rotatively retained within and with respect to said carriage.

It is the further object of this invention to provide a support for the carriage lead screw which will permit manual rotary movements thereof, which movements will cause corresponding movements in one direction or the other of the aforesaid nut thereby controlling movements of the carriage under such manual control.

It is the further object of this invention to provide a motor driven mechanism for effecting reciprocal arcuate or rotary movements of said infeed nut upon said lead screw to provide for reciprocal in and out feed movements of'said carriage and. the regulating wheel mounted thereon.

It is the further object of this invention to provide a pair of rotary cams arranged in such timed relation to each other and positioned relative to a reciprocal cross head so as to effect timed reciprocations thereof whereby said carriage is fed inwardly to a predetermined position, retained in this position for a short period, and then withdrawn carrying the regulating rwheel therewith to another predetermined position.

It is the still further object of this invention to provide a work piece ejecting mechanism which is associated with and controlled by said infeed attachment whereby said work piece is ejected from its position between the grinding wheel and the regulating wheel as and during the outward feeding of said regulating 'wheel under control of said attachment.

It is the further object of this invention to provide a pneumatic mechanism controlled by a third cam on said attachment to effect automatic ejection of the work piece in timed relation to the controlled outfeeding movements of said carriage. I

It is the still further object of this invention to provide means for regulating the extent of the in and out feeding as well as the speed thereof.

iii

These and other objects will be seen from the following specification and claims in conjunction with the appended drawings in which:

Fig. 1 is a front elevational view of the center. less grinding machine with the automatic in-lfeed attachment thereon.

Fig. 2 is a transverse plan view of the mechanism comprising the infeed attachment as assoe ciated with the machine carriage which is fragmentarily shown.

F g. 3 is a right end elevational view of the infeed attachment thereof.

Fig. 4 is a front elevational view thereof as associated with the machine carriage which'is fragmentarily shown.

Fig. 5 is an enlarged plan section taken on line 5-5 of Fig. 4; and

Fig. 6 is an elevational section taken on lin 66 of Fig. 4.

It will be understood that the above drawings illustrate merely a, preferred embodiment of the invention and that other embodiments are contemplated within the scope of the claims hereafter set out.

Referring to Figure 1 the centerless grinding machine includes the base i supporting the bed 2 which carries the stationary grinding wheel housing 3 journalling the abrasive grinding wheel 4.

A truing attachment 5 is generally indicated as carried by wheel housing 3 for truing said grinding wheel in a manner which forms no part of the present invention, and for this reason fur ther description of the structure thereof is omitted.

It is sufficient to state that the grindingwheel ispositioned within housing 3 and centrally secured to the rotary drive shaft ii which is driven by a suitable electric motor preferably, which motor is not shown in the drawing, as" the mechanism for rotating said grinding wheel itself forms no part of the present invention. It is suflicient to state that grinding wheel 4 is adapt"- ed for rotation with respect to and in engaging relation with the cylindrical shaped work piece I.

The aforesaid'bed 2 includes the guideways ii which are arranged at right angles to the axis of the grinding wheel shaft ii and upon which is mounted the upper slide 9. Y

The upper slide 9 hereafter denoted as the carriage 9 is suitably mounted upon the guide ways 8 whereby said carriage is adapted for'lre ciprocal adjustment at right angles to the axis of the Work piece]. I

Regulating wheel housing I0 is secured to and 1 3 carried by carriage 9 at its left end and is adapted to house and journal the rotatable regulating wheel H which engages work piece I on its side opposite from the grinding wheel 4, said regulating wheel being adapted to maintain said Work piece against the surface of said grinding wheel and secured within its housing Hi, there being preferably an electric motor joined to said shaft for operating the same, there being also suitable mechanism for regulating the speed of rotation of .the regulating wheel H which forms no part of the present invention and consequently its description is omitted. It is sufi'lcient to state for the purpose of the present application that the regulating wheel H is power rotated by the shaft which is shown in Figure l. A truing attachment generally indicated by the numeral 16 is ad-justably mounted upon the regulating wheel housing H! for truing said regulati-ng wheel H. As the structure of said trulng attachment forms no part of the present invention, its description is omitted with the exception that the truing hand wheel is designated by the-numeral -l 1.

Referring to Figure l a bracket 18 is secured to the right end of bed 2 and projects upwardly therefrom to journal and support :the lead screw 19 which carries the operating spokes or hand wheel .20 to effect manual rotationof said lead screw.

Collars 2"! and '22 are secured to lead screw 19 upon opposite sides of the bracket it to .efiect-ively retain .said lead screw against longitudinal movement relative to said bracket.

As shown in Figures 1, 2, 3 and .6, the other end of said lead screw extends through and is in threaded engagement with the infeed nut 23 which projects into :the carriage Band is rotative- 1y positioned therein as by the thrust bearin 24. Said bearing is threadably or otherwise secured within carriage 9 and retainingly engages the annular shoulder 25 on the infeed nut 23 so that :the latter is rotatively retained with respect thereto.

' From the above description it is seen that upon manual rotation in one direction or the other of the lead screw 19 as by its hand wheel 20, the infeed nut, retained against rotation in the manner hereafter set out, is adapted to movements to the right or the left in Figure 1 upon said rotated lead screw.

In view of the connection between the infeed nut 23 and carriage 9 it is seen that such movements of the nut will be transmitted to the carriage ;9 so that the same and the regulating wheel H can be initially adjusted to the approximat desired position with respect to the grindingwheel 4.

The present invention includes an automatic mechanism now to be described whereby under power operation said inieed nut will be intermittently and reciprocally rocked upon the lead screw l9. Here again, rotary movement of the infeed nut upon said lead screw will cause movements of said nut 23 to the lighter to the left upon the stationary lead screw 19 to therebyeffect ,5. corresponding movements to the right or to the left of the carriage 9 shown in Figure 1.

Normally there is suflicient inertia as between the reciprocated arcuately moving infeed nut 23 and the lead screw l9 that the latter is relatively stationary. Consequently such reciprocal movements of the infeed nut are adapted to effect progressions to .the right .or to .the left of said gnutzupon-the :relatively stationary lead screw l9. To assure that the lead screw IE will not rotate, .a suitable friction clamp may be employed if desired.

'Reierring to Figure 6 the lead screw nut 23 is shown mounted upon and in threaded engagement with the ,lead screw IS, the latter being relatively stationary. lhe hollow clamp 25, split at 21 is adjustably positioned around the infeed nut 23 and efiectively secured thereto as by the adjustable bolt 28 which inter-connects the free ends 29 of said clamp. 7

An extension '30 "forms apart of the clamp 25 being arranged diametrically from the free ends 2-9 thereof, said extension being slotted at 3! to adjustably receive the bolt 32 ior swivelly joining one end :of the link 33 to said clamp.

As shown in Figure 2 the bolt '32 threadably engages the link as and projects through the slot 31 in the clamp 26 and "is retained with respect thereto by thenut 34.

The opposite end of the link 33 is joined by a suitable pin'34 to one end of the reciprocal cross head .35. The latter is iormed with the bosses 3.6 oppositely extending therefrom and arranged at its ends, said "bosses having circular openings to receive the supporting shafts .3?! which respectively extend thru said bosses. .By this construction the cross head 35 is adapted for reciprocal sliding movement upon the spaced transverse rods .31.

As shown in the drawings a suitable hollow framework or housing 3.8 projects from the right end of the carriage 19 :and is secured thereto by the bolts 39 as shown in' Figure :4. The respective opposite ends of the shafts .31 are nested and secured within the bosses =49 which have central openings to receive said shafts and which bosses form an integral part of the housing 38. Consequently it appears that (the housing 38 which supports the reciprocal cross head 35 is mounted and secured upon carriage 9 for movement therewith.

The cross head 35 which is adapted to affect reciprocal rotary movements of the infeed nut 23 thru the interconnecting link 33 has a pair of spaced cam engaging rollers 41 and 42 arranged adjacent the opposite end of said cross head as illustrated in Figures 2, 3, 4, .5 and 5. Said rollers are intermittently and alternately engaged by the rotatable cams 43 and 44 respectively whereby said cross head is projected to the left as in Figure 6 by the cam 43 and subsequently to the right by the cam 44!.

.Both of the cams 43 and M are mounted upon the cam driving shaft 4.5, being keyed thereto at 45 for rotation therewith. As shown in Figure 5 the left end of shaft 45 is supported and journalled within the ball bearings 41 supported within the projecting boss 48 forming a part of the housing v33. The right end of cam driving shaft 45 extends over and is suitably secured to rotatable drive shaft 48.

The said shaft 49 extends from the speed reducer 59 which is in the upright position shown in Figure 4, being secured to housing v38 by the bolts 51. Said speed reducer is initially operated by the driven shaft 52 which projects into said speed reducer and which is suitably interconnected with the drive shaft 49 by a plurality of gears. Theparticular construction of the speed reducer forms no part of the present invention; and consequently further description thereof is omitted.

' As shown in Figures 2, 3, 4 and 6 driven shaft 52 is rotated by the pulley wheel 53 driven by radius, and this extends over an arc of approximately 90 degrees. During the period of engagement of the cam rotating in a counter-clockwise direction it would appear that this portion of the cam between the points a and b maintains the cross-head 35 in its extreme position; to the left as in Figure 6. This corresponds tothe infeed position of the carriage 9 at which and during which period the work piece is being ground. After cam 43 leaves the roller Al the second cam 44 is now in operative engagement with cross-head operating roller 42 for projecting cross-head 35 in the opposite direction upon its supporting rods 31. And it is this movement of the cross-headwhich is transmitted to the link 33 which governs the outfeeding of the carriage 9 to permit ejection of the work piece and the insertion of a new work piece upon the work blade i 2 between the grinding wheel 4 and the regulating wheel ll.

At the'same time as the cam begins its effective engagement with the rollerf42 initiating the outward feed movement ofthe carriage, a third cam 58 is brought into operative position to energize a pneumatic work piece ejecting mechanism, to clear the work blade i2 and to provide for the insertion of the new work piece thereon.

More particularly as shown in Figures 2, 3 and l, this .cam 58 is secured upon the cam driving shaft 45 by the locking bolt 59, Figure 4, for rotation with said shaft. Said camis adapted to intermittently engage roller 6!! on the. control arm 6| which projects from and is pivotally joined at 62 to the control Valve housing 63.

I Referring to Figure 4 a pipe fitting 64 is provided at the top of housing 38 to which may be joined a suitable source of compressed air for example, said compressed air being delivered to the cross-fitting or T 65 there being .a suitable hand valve 66 interposed. A suitable pressure gauge 61 is joined at 68 to the fitting 65 while a suitable fluid delivery pipe 69 is joined to said fitting at the point 10. The pipe 69'which in this case delivers compressed air, extends downwardly, being joined at H to an inlet fitting 12 of the control valve housing 63, said control valve having a. compressed air supply pipe 13 as shown in Figure 3. 1

Referring again to Figure 3 there is diagrammatically shown the work piece ejecting cylinder 74 which is arranged and positioned in longitudinal alignment with the workpiece I supported upon the work blade l2. Piston I is slidably movable within cylinder 14 and has projecting therefrom the piston rod 16 which extends through the outer end of said cylinder and is adapted for operative ejecting engagement with one end of the work piece 1 as shown.

' Coiled spring 11 is positioned within said cyl-" inder with its ends respectively bearing against one inner wall of said cylinder and said piston so that when inoperative said piston and piston rod assume theposition shown in Figure 3.

The compressed air supply pipe 13 from the control valve 63 is joined at 18 to the right end of cylinder 14 for communication with its interior upon the side of said piston opposite from said coiled spring. 7

Upon energization of the control valve 63 through intermittent upward pivotal movement of the control arm 6| through operation of cam 58, compressed air is supplied to the pipe 13 for;

delivery to the interior of the ejecting cylinder 14. The pressure of the compressed air overcomes the force in the spring 11 and the piston I5 is moved to the left forcibly so that the rod 16 operatively bears against and ejects the work piece 1 from its support I2.

As soon as the cam 58'passes the control valve actuating arm 6|, the latter returns to the position shown in Figure 3 and the supply of compressed air or other fluid is cut off from the pipe,

13, the latter being provided with a suitable ex;- haust for the escape of the air remaining in said cylinder and pipe once the pressure has been removed. When said pressure has been removed coil spring 77 is effective to effect the return of. the piston 15 and its rod to the position shown in Figure 3. In this inoperative position the new work piece 1 may be properly positioned upon the work blade l2 between the grinding wheel 4 and the regulating wheel ll.

Referring now to Figures 2 and 3 the electric motor 55, which drives the control cams 43, 44 and 58, has a mounting bracket I9 which is secured to the mounting plate 80 by the bolts 8|. The plate 80 which is substantially rectangular in shape has a pair of supporting arms or bifurcation 82 at its lower end which have transverse openings therethrough for receiving the mounting rod 83.

The rod 83 is supported at its opposite ends within corresponding openings formed in the parallel spaced supports 84 which project rearwardly from the lower end of the housing 38. Consequently the mounting plate so is pivotally supported upon the housing 38 by means of the rod 83.

Nut 85 is secured to and projects upwardly from the central top portion of mounting plate 80 and threadably receives therethrough the motor adjusting screw 86. The latter is anchored and retained at its outer end within the guide and support 81 which projects oppositely from a correspondingportion of the housing 38. It will be seen that the mounting plate 80. is thus pivotally adjusted upon the supporting housing 38 and may be adjusted thereon in either a clockwise or counter-clockwise direction for regulating the speed of rotation of the pulley 53.

Pulley 51 is an adjustable type pulley which is split transversely of its axis and has a changeable pulley support i. e. the pulley support being of variable diameter. The adjustable pulley is a standard type whose detail of construction forms no part of the present invention. In operation; however, if the motor 55 is pivoted in a clockwise direction increasing the center distance between pulleys 53 and 51, it is so constructed that said pulley 51 starts to separate with result that the driving diameter thereof is reduced with a consequent reduction in the speed of movement of the pulley belt 54. It likewise follows that if Mace-2s the motor mountin is pivot d n'tne QEFQSit/B direction from such adjusted position, the pulley under the. operation of its springs', not shown,v tends to. move together increasing. the driving diameter thereof, to thus increase the speed of movement of the. pulley belt 54.

Referring to Figure 3, bolt 32 may bB-IOOSBHGI1,. and the end of link: 33 slidably adjusted withinv slot 3}. to thereby determine the extent of the rotary arc imparted to feed nut 23. The. greater the arc, the greater will be the amount oi the "in." and.o-ut feeds.

7 As shown in Figure 2a. hand. lever 88- with handle 89 is removably secured to feed nut 23. b-ya split collar 90 thereon which projects around. nut. Thiscollar is removably secured there-l to by the bolt 9|. 1

In the conventional operation oi inieed at tachmsnts, the hand lever 88 is employed to manually control the in and out movements of the feed carriage. During the period of. such manualv control the power operated. inieed ailtachment is rendered inefiective by loosening the. bolt 28. It. follows that to make the infeed. adjustment automatic, all that is. necessary is to tighten this bolt .28 and at the. same time-loosen the bolt-9 I to render the hand lever 83 inefiective. Consequently it is clear that. it is a relatively simple matter to change over. from manual control to. automatic .controL.

Having described my invention, reference should now be. had to the claims. which follow. tor determining the scope thereof.

I claim:

1.. In a grinding. machine having an adjustable feed carriage, a stationary lead screw, a reciprocally rotatable feed nut on said screw and retain--. ingly engaged by said carriage for effecting in and out adjustments thereof relative .to saidlead screw, a longitudinally. reciprocallinl; pivotally and, eccentrically joined at one end to said nut iorrocking the same on saidscrew, a recipe. rocal cross-head joined to the other end oisaid and a pair of coaxial rotatable cams respectively. and. intermittently enga i g QppQSii/B n of said cross-headfor effecting reciprocal movemerits-thereof.

2. In combination a stationary lead screw, a feed nuti threaded thereon, a reciprocal link pivotally and eccentrically joined at one end to said. 1

nut. for .eiiecting reciprocal rotary movements thereof,v a reciprocal. cross-head pivotally joined to the other end of said link, and a pair. at coaxial rotatable cams intermittently engagingv op: positeends of said. cross head for efiecting recipe rocal movements thereof, whereby said nut is intermittently moved in opposite directions 1on9. gitudinallyof said lead screw. 7 I 1 In agrinding machine having. an adjustable feed carriage,v a. stationary lead screw, a recipm-i cally rotatable feed. nut on said screw and retain? ingly engaged by said carriageforefiecting in and. out adjustments thereof relative to said leadscrew, a. reciprocal. cross head pivotally andv eccentrically joined to said nut. for. rocking the sameon said screw, and a pair of coaxial rotatable cams respectively and intermittently engaging opposite ends. of said cross head for effect.- in'g, reciprocal movements thereof,

a. .In a grinding. machine havin adiustable 8-. teed carriages stationary"leadscrema rec-inrocally rotatable food not on. said screw and. retaininsly aged by said Carriage. for effect ing in and out adjustments thereof relative to. said lead screw. a longitudinally reciprocal link pivotally and eccentrically joined atone-end.-

said nut for rocking the same on said screw a reciprocal cross head joined to the other end oisaid link, and a. pair of. coaxial rotatable cams respectively and intermittently engaging, opposite. endsof, saidcrosshead ior effecting reciprocal movements thereof, said cams being so iormed. and arranged. with. respect to. each. other. that. there isa lag of the carriage in its infed position to permit grinding of the work piece.

5.- In'a grinding; machinehaving a Work rest andan in and outwardly adjustable work regulate. ins; wheel supporting carria e, a pneum tic eiec tor in axial alignment with the work piece on, said work rest and adapted for operative encasement. therewith when energized; a stationary lead screw, a reciprocally rotatable feed nut on said: screw and retainingly engaged. by said carriage for efiecting, in and out adjustments thereof relative. to saidlead screw, a longitudinally reciprocal link-pivotally and. .eccentrically joined. at one end to said nut for rocking the same onsaid screw, a reciprocal cross-head joined tothe. other endoi said link, a pair of coaxial rotatabl cams respectively and intermittently engaging opposite ends of said. cross-head for effecting reciprocal movements thereof a control 'valve incommunication with said ejector. for supplying compressed air thereto energizing the same, and a. hirdcoaxialrotatable cam. intermittently engageable with said valve for operating the, same, said latter cam being so constructed and arranged. with respect to. said other cams that said ejector wiilbe energized simultaneously with. theengagcment of one of saidiother cams. effecting out feeding movement or said carriagerelative to said work piece, f

.6. In a. grinding machine. having an. adjustable feed carriage, .a stationary lead screw, a roomrocally rotatable feed nut on saidv screw and-retaininglylengaged by said carriage for effecting in and out. adjustments thereof relative to said lead screw, a longitudinally reciprocal link pivot, ally and eccentrically joined. at one end to said nut for rocking the same on said. screw, a reciprocal cross-head joined to the other end of said. link, a pair of coaxial rotatable cams respectively and'intermittently en aging, opposite ends of said cross-head for effecting reciprocal movements thereon a cam drive shaft on which said cams are secured, and adjustable means for regulate ing the speed of rotation thereof. 7

KEITHANDERSQN'.

EEFERENGES orren The following references are of record in the file of this patent: v

UNITED STATES PATENTS Heckethorn =.mgcngllec. 1'7; 1.9%

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