US1925908A - Grinding machine - Google Patents

Description

Sept. 5, 1933. R.'RE|D ETAL I 1,925,908

GRINDING MACHINE Ffiled May 6, 1931 7 Shuts-Sheet 1 @7qm Mama, cl-mu,

7 sheets-sheet 2 Sept. 5, 1933. R: REID EIAL GRINDING MACHINE Filed lay-6, 1931 Sept. 5, 1933. I I R. REID ,ET AL 1,925,908 GRINDING MACHINE Filed May 6, 1931- 7 Sheets-Shed 4 %& LU

7 Sheets-Sheet 5 7 Sheets-Sheet 6 erll o 7'6.

R. REID El AL GRINDING MACHINE Filed May 6, 1931 Sept. 5, 1933.

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Sept. 5, 1933. R AL 1,925,908

GRINDING MACHINE Filed May 6, 1951 7 Sheets-Sheet 7 2/ $95.. AI, (MM 4.. V ai Patented Sept. 5, 1933 I Q um ra stairs rarest or es GRINDING MAG Robert Reid, Beveriy, and Andrew 8. Reid, Wenham, Mass.

' Application May a, rear. Serial 1%.. assess a oiaims. (oi. 51-92) This invention relates to a grinding machine mensionof 1/1o,oo0 of an inch and produce a and more particularly to a surface grinding masmooth finished ground surface of the highest and chine. most desirableeharacter.

In general the object of the invention is to proefe ri g now to the dr w k 8S abfivfi vide a novel and improved surface grinding mastated illustrates the preferred embodiment of w chine with which surfaces may be ground to acthe invention, comprises the frame of the ma curate dimensions, chine which is of general T-shape, and upon the With this general object in view and such othforward portion 12 of which the work supporting ers as may hereinafter appear, the invention contable 14 is mounted in the usual manner in suit 10 sists in the surface grinding machine and in the able guideways to be capableof being recip- 55, various structures, arrangements and combinarocated back and forth upon the supporting tions of parts hereinafter described and particframe. The second portion 16 of the frame it ularly defined in the claims at the end of this Op a e y a d da l pp a mounting 2Q specification. for a grinding wheel 22, and provision is made,

'15 In the drawings illustrating the preferred emas will be described, fo fe d h mounting bodiment of the invention, Fig. 1 is a front eleand the grinding wheel supported thereby vation of the present surface grinding machine, t ve ely o t e W t progressively 38917156 Fig. 2 is a sectional plan view of the base porthe grindin W e 22 to grind Over the fleshed tion of the machine; Fig. 3 is a diagrammatic view Surfacs 0 t W a the W Supporting hamsillustrating the piping connections for reciproi8 p vc ted bac and 0 eating the work support and for moving the As herein shown, the grinding wheel 22 is se= grinding wheel transversely of the work; Fig. 4 cured upon the end of its spindle 24 in any usn= is a vertical sectional view taken on theline 4-4 al 01 preferred manner and t e Spindle is 3 th of Fig. 2; Fig. 5 isa vertical longitudinal sectional nalled in bearings 26 wit in a tub a p i view through the grinding head; Fig. 6 is a verof a housing 2 Comprising a d w ic is tical sectional view taken on the line 6-6 of mounted, as will be described, in the general Fig. 2; Fig. '7 is a sectional plan illustrating the housing or mounting an. In order to retain the cross feeding mechanism; Fig. 8 is a sectional housing 20 upon the portion 16 of the frame and detail illustrating the mechanism for controlling to permit it to slide thereon, the mounting 2c is the operationof the cross feed of the grinding provided with guideways 31, as shown in Fig. 4,

wheel; Fig. 9 is a sectional detail on the line which cooperate with guides 33 on the upper sur- 9-9 of Fig. 8; Fig. 10 is a section on the line face of the portion 16 of the machine frame to 10-10 of Fig. 5; Fig. 11 is a sectional detailpermit the housing 20 with the grinding head as 35 onthe line 11-11 of Fig. '7; and Fig. 12 is a to be moved as a unit and to move the grindsectional view takenon the line 12-12 of Fig. 7. ing wheel 22 transversely across the work.

- In its preferred form the present invention As illustrated in Figs. 4 and 5, the housing contemplates a surface grinding machine, and 29 is hung or suspended within the general housmore particularly a surface grinding machine in ing 20 by an elongated internally threaded sleeve which the grinding operation is performed by a 30 having a flange 32 which rests upon the top rotary grinding wheel mounted so that the peof the mounting or housing. 20. The internally riphery engages the work. Provision is made for threaded sleeve 30 cooperates with and has ex-' reciprocating the work. and for moving the grindtended ther'ethrough in threaded engagement ing wheel in a direction transversely of the di- "therewith a threaded vertical shaft 35, the lowrection of recpirocation of the work. Provision or end of which is secured in fixed relation to is also preferably made for adjustably positionthe housing 29 by being keyed by a key 40 to the ing the grinding wheel toward and from the work hub of a beveled gear 42 and the latter is interto accurately control the grinding cut. posed between the members of ball-bearings 44,

In the preferred embodiment of the invention 46, abutting hubs 48 forming a part of the housprovision is made for, operating the grinding ing, so that the beveled gear 42 and the bearwheel and for effecting the reciprocation of the ings 44, .46 connect the shaft 35 with the hubs work and the cross feed of the grinding wheel 48 and consequently with the general housing 29 in a manner most conducive to a minimum of which the hubs 48 form a part, as clearly illusamount of vibratory effect upon the grinding trated in Fig. 5. hi order to prevent relative rowheel, thus permitting the machine to be used tation between the elongated threaded sleeve 30 no to grind with maximum accuracy and to a diand the housing 20, a plate 50 secured by bolts 52 to the housing is pinned to the top of the sleeve 30, as shown in Fig. 5 and in detail in Fig, 10, and the upper end of the shaft 35 may and preferably will be protected by a suitable casing 54 secured by set screws 56, or otherwise, to the, sleeve 30, as clearly shown in Figs. 5 and 10. The threaded shaft 35 serves therefore to sus- "pend the grinding unit 29 within the outer hous-- ing 20 and 'also serves upon rotation to raise and lower the housing 29 and grinding wheel and unit mounted therein-to adjustably position the grinding unit toward and from the work, and to thereby regulate the depth of the grinding cut. As illustrated in Fig. 4, provision is made for counter-balancing most of the weight of the housing 29 and the grinding unit mounted therein,'and as herein shown counter-weights are connected by cables 62 running over idlers 63 to the housing 29 within which the grinding wheel is mounted. Provision is made for rotating the vertical shaft 35 to raise or lower the housing 29 with relation to the housing 20 and to the work supported on the work supporting table, and as best illustrated in'Fig. 5, the machine is provided with an operating shaft 41 journalled in bearings 43 in the housing 29 and provided with a bevel gear 45 which meshes with the bevel gear 42 keyed to the shaft 35. Upon its forward or outer end the operating shaft 41 may and preferably will be provided with an operating handle or wheel 47 preferably having a Vernier scale to permit accurate adjustment of the grmd- 8 wheel toward and from the work.

In the preferred embodiment of the invention provision is made for rotating the grinding wheel by means of the rotor.74 of an electric motor mounted directly upon the operating spindle 24. The spindle 24 is secured to the rotor of the motor and the latter is secured to the housing 29, thus forming a grinding unit mounted in the housing 29, and capable of being moved toward and from the work when the shaft 41 is rotated by the operator turning the handle orwheel 47; Asclearly illustrated in Fig. 5, the rotor of the motor indicated generally at 74 is clamped on' the spindle by a lock nut 75 and the end bearing 76 for the spindle 24 is mounted in a supporting member '78 forming part of the housing 29 and the spindle is provided with a lock nut 79 normally concealed by a removable cover member 80. The end plate 82 constituting a part of the housing 29 is removable .to afford access tothe motor and its supporting parts.

, In order to reciprocate the work, provision is made for reciprocating the. work supporting table, and as herein shown the work. supporting table is reciprocated by fluid pressure derived from a pressure pump 81 (see Fig. 3) driven by a motor 83 coupled directly therewith. Oil is preferably utilized as the fluid, and is delivered under pressure from the pump through a pipe line 84' into a valve mechanism indicated generally at 86. The valve mechanism 86 functions to control the admission and return of the oil from the pressure pump to operating cylinders, as will be described, and in practice the valve 86 may comprise any usual or preferred form of reciprocating slide valve such as has been heretofore used to control the passage of a fluid from an incoming port to two outgoing ports, and the exhaustion or return of the fluid from either port to a return port, as for example a valve.of the type of the ordinary reciprocatory steam valve. In practice the entire mechanism 86 may be purchased as a unit in the market, and one form is obtainable under the trade name *oil gear. inasmuch as the. details of construction of the valve mechanism 86 of themselves form no partof the invention, further description thereof is deemed unnecessary. I

The valve 86 is provided with discharge lines 90, 92 which lead to the end of cylinders 94, 96, respectively, provided with pistons 98, 99, adapted to be forced from the cylinders under the influence of the oil pressure from the pump when the valve mechanism 86 establishes communication between the inlet 84 and either of the pipe lines 90, 92. The machine is also provided with a return pipe 100 leading from the valve mechanism 86 back to the intake side of the pump, and in the operation'of the table operating mechanism when one piston is beingforced outwardly by the oil pressure from the pump to thereby move the table in one direction, this same movement is utilized to effect the return movement of the oilfromthe other cylinder as the piston is moved by thetable into the cylinder. At this time the particular line 90 or 92 is connected 'by the valve 86 with the return line 100 leading back to the pump. Referring now to Figs. 3 and 6, provision is made for directly connecting each piston 98, 99 with the table, and as herein shown this connection is made through depending arms 101 and 102 projecting from the bottom of the table and fastened directly to .the end of the pistons.

Provision is made for actuating the valve of the valve mechanism 86 tocontrol the operation thereof to reciprocate the work supporting table through a definite stroke, and this is preferably accomplished, as will be described, through connection with the work supporting table 14.

In orderto cause the grinding wheel to traverse transversely across the work or to move, in a direction transversely of the direction of recip- -rocation of the work supporting table, provision is ma'defor advancing the entire housing 20, and for this purpose the housing is provided with a rack 110 secured to the under side thereof and which is adapted to be engaged by a pinion gear 112, see Figs. 2 and 4, so that as the pinion is rotated, the rack is advanced to move the housing and the grinding unit carried thereby back and forth as the housing slides upon the guides upon the top of the portion 16 of the frame. The pinion 112 is mounted upon the upperend of a short shaft 113 having a worm wheel 114 upon the lower end thereof with which a worm 116 cooperates, and the worm 116 is mounted upon v the end of an operating shaft 118 journalled in bearings 119, 120 in a yoke' 122 forming part of the machine frame. Provision is made for automatically advancing the housing 20, and the grinding unit carried thereby, an increment at each reciprocation or stroke of the tabla-and as illustrated herein fluid operated mechanism is provided for effecting the operation of the cross feed of the housing 20 and the grinding unit. Referring now to Figs. 3 and 7, the valve 86 is provided with a second set of discharge pipes120, 122 which lead from the housing of the valve 86 to the ends of a second set of cylinders 124, 126. The cylinders 124, 126 are provided with pistons 150, 152 and the ends of the pistons are extended a substantial distance beyond the ends of the cylinders 124, 126 and have formed therein two sets of racks 154, 156, the racks 154 being formed in the top of the pistons,-and the racks 156 being formed in the adjacent sides of the pistons, as clearly illustrated in Fig. 7. The racks 156 in the sides of the piston mesh with a common 'ipca'eos 'idler gear l58 to gear together the two'pistons so that when one piston is being moved outwardly by oil pressure behind it, the other piston will be forced inwardly into its cylinder to exhaust oil therefrom.

Provision is made for utilizing the forward movement of each piston 150, 152 from its cylinder under the influence of oil pressure from the 'oil pump to rotate the actuating pinion 112 and thereby advance the rack to cause the housing to be moved transversely of the work. As herein shown each rack 1*54 meshes'with a pinion 160 formed on sleeves 161 loosely mounted upon a counter shaft 163. The sleeves 161 carry pawl arms 162 provided with pawls- 164 which are spring-pressed into engagement with the teeth 'of square-toothed ratchets 165 so that upon the forward stroke of the pistons 150, 152, the pawls are advanced and operate to advance the ratchet wheels. Both ratchet wheels are keyed to the counter-shaft 163," and ass. result upon each forward stroke of a piston the shaft is rotated. The rotations of the shaft are transmitted through a driving gear 170 fast thereon to a pinion 1'72 mounted upon a second counter shaft 174, and the latter is provided with a bevel gear 175 which meshes with a similar gear 1'16 on the lower end of a vertical shaft 178 journalled in a suitable bearing 1'19 in a bracket 180 secured to the machine frame, as illustrated in Fig. 6. The vertical shaft 173 extends upwardly through a bearing 182 in the yoke 122, Fig. 6, and its rotations are transmitted to the operating shaft 112 through a differential gear train including a bevel gear 184 upon the upper end of the shaft 178 and through bevel gears 185, 186 loosely mounted upon the operating shaft 113, both of which mesh with the bevel gear 184. A slidable clutch member 187 is provided between the two loosely mounted bevel gears 185, 186 and is keyed to the shaft and adapted to be moved into engaging position with either of the two bevel gears to thereby clutch one of suchgears to the shaft and cause rotation of the shaft in either one direction or the other according to the bevel gear with which it cooperates. In this manner the shaft 118 may be rotated in either direction, and consequently the grinding unit carried by the housing 20 may be caused to traverse in either one direction or the other depending upon the position of the clutch. Provision is made for manually moving the clutch member, and as herein shown an operating lever 191, see Fig. 8, on the outer end of a shaft 192 serves to permit the shaft to be turned and to cause a cam 194 fast thereon to cam an intermediate member 196 in either one 1 direction or the other, and the intermediate cam member is provided with a yoke 198 which fits in a recess 199 in the clutch 18'! so that as the operating lever is turned the clutch may be caused to engage either one gear or the other. The work supporting table 14 is provided with lugs 205, 206 which engage the operating lever 190 to control the valve 86 automatically.

In order to limit the stroke of the pistons 154, 156 of the cross feed mechanism, adjustable abutment members 200 are provided, herein shown as comprising resilient buffers 201 mounted upon the ends of rods 202 slidably mounted in bearings 203 in a bracket 204i forming a part of the machine frame, and provision is made for adiustably moving the abutments toward and from the ends of the pistons 154, 156 by an operating lever 210 on a shaft 212 having spiral gears 214 which mesh with spiral gears 216 formed on nuts an in threadedengagementwith the threaded ends 218" of the. abutment rods 202, as illustrated in Fig. I. Rotation of'the lever 210 causes the nuts 217 to be turned in their bearings and consequently to cause the abutments to be moved in or outin unison, and thus effectively limit the outward strokes-of the'pistons at any desired point. Provision is also ado for permitting the housing to be moved manually in a direction transversely voi. the-work, and as herein shown the manually operated mechanism comprises a hand wheel 220 'slidably mounted on the end of the shaft 118 and whose movements lengthwise of the shaft are limited in one'direction by aretaining'nut 222, see Fig.' dwhich is pinned to the shaft and positioned so 'as to permit the hand wheel to be moved to cause the ends of lock fingers or bolts'224 to project into or be withdrawn from correspondingly positioned sockets 226 of a series of such sockets formed in a collar 230 pinned to the shaft 118.

The machine may and' preferably will be provided with a suitable guard 250' for the upper portion of the grinding wheel and with provision for the supply to'the grinding wheel of the usual dorm of grinding fluid; and as illustrated in Fig.

1 such grinding fluid may be introduced from the source of supply, not shown, through the pipe 252 controlled by the valve 25d and delivered in astream against the operative portion of the grinding wheel.

From the description thus far, it will be ob served that in the present grinding machine the grinding wheel is mounted in a manner such as to reduce to a minimum the vibration imparted to it by its driving mechanism. The usual vibrations incident to belt drives and thelike because of belt slaps are avoided, and it has been found that the direct mounting of the motor on the spindle of the grinding wheel unit not only facilitates the adjustment and adaptability of the grinding unit to work of difierent size, but also insures smooth vibrations operation of the grinding wheel upon the work, thus insuring productiogi of the ground surfaces of the highest charac er.

It will also be observed that the fluid operated mechanism for feeding the grinding unit transversely oi the work, as well as the fluid operated mechanism for reciprocating the work, insures a smoothness of operation and an absence of vibration which supplements the improved drive for the grinding wheel itself to produce a comeration with maximum accuracy and to produce surfaces ground to extremely small fraction of an 1rilnch, such for example as to 1/10,000 of an inc While the preferred embodiment of the invention has been herein illustrated and described, it will be understood that the invention may be embodied in other forms within the scope of the following claims.

Having thus described the invention, what is claimed ls:-

1. A beltless surface grinding machine in which vibration is reduced to a minimum having, in combination, airame, a work support mounted for reciprocation thereon, iiuid operated means for reciprocating the work support, a grinding unit mounted upon the frame capable of movement transversely of the work support and also toward of which thegrinding wheel is mounted, a motor having its rotor mounted directly on the second end portion of the spindle, means for adjustably moving the entire grinding unit toward and from the work support, and fluid operated means for automatically effecting the transverse movement of the grinding unit to progressively move the grinding wheel across the work.

2. A beltless surface grinding machine in which vibration is reduced to a minimum having, in combination, a frame, a movable work supporting member mounted for reciprocation thereon, fluid operated means for reciprocating the work support, a housing mounted upon the frame and movable transversely thereof, and a second housing mounted upon and carried as a unit with the first housing and capable of movement with relation thereto toward and from the work support, means for adiustably moving the second housing with relation to the first housing, a grinding unit mounted within the second housing and comprising a spindle, a grinding wheel mounted upon one end of the spindle, and a motor secured to the second housing and having its rotor mounted upon the second end of the spindle, and fluid operated means for effecting the transverse movement of both housings and the grinding unit carried thereby.

3. A beltless surface grinding machine in which vibration is reduced to a minimum having, in combination, a frame, awork support mounted for reciprocation thereon, fluid operated means for reciprocating the work support, ahousing mounted upon the frame to be capable of movement transversely of the work support, a second spindle, and fluid operated means for eifecting transverse movement of both housings and the grinding unit transversely of the work. I

4. A beltless surface grinding machine in which vibration is reduced to a minimum having, in combination, a frame, a work support mounted for reciprocation thereon, fluid operated means for reciprocating the work support, a housing mounted for movement transversely of the work support, a second housing, means including a threaded member connecting the second housing with the first housing to permit the second housing to be adjustably moved with relation to the first housing and toward and from the work support, manually operated means carried by the second housing for effecting said adjustment, a

grinding unit carried by the second housing comprising an elongated spindle, a grinding wheel mounted upon one end thereof, and a motor having its rotor mounted directly upon the second end of the spindle, and fluid operated means for effecting the transverse movement of both housings and the grinding unit during the operation of the machine.

ROBERT REID. ANDREW S. REID.

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