US2420081A - Traversing mechanism for grinding machines - Google Patents

Description

y 1947. R. A. JOHNSON I TRAVERSING MECHANISM FOR GRINDING MACHINES Filed Marsh 26, 1945 '3 Sheets-Sheet l 1 Raymond A. Johnson May 6, 1947. R. A. JOHNSON 2,420,081 TRAVERSING MECHANISM FOR GRINDING MACHINES Filed March 26, 1945 5 Sheets-Sheet 2 g1 3mm 60 Raymond A .Johnson May 6, 1947. R. A. JOHNSON 2,420,031

TRAVERSING MECHANISM FORGRINDING MACHINES Filed March 26, 1945 3 Sheets-Sheet 5 Patented May 6, 1947 TRAVERSING MECHANISM FOR GRINDING MACHINES Raymond A. Johnson, Dallas, Tex., assignor, by

mesne assignments, to Storm-Vulcan Manufacturing Company, Inc., Minneapolis, Minn., a corporation of Minnesota Application March 26, 1945, Serial No. 584,789

4 Claims.

This invention relates to new and useful improvements in grinding machines.

One object of the invention is to provide an improved grinding machine wherein the work and grinding means are independently supported and movable relative to each other, whereby the machine may be of minimum size so as to require a minimum amount of space without impairing the ease of performing or the quality of the grinding operation or increasing the time necessary for such operation.

An important object of the invention is to provide an improved grinding machine having a pair of longitudinally slidable tables, with the work being supported by one table and the other table carrying the grinding means, which tables are adapted to be simultaneously moved longitudinally of each other in opposite directions to vary the relative positions of said work and grinding means and which are so arranged that one table may be moved slight distances in either direction independently 0f the other table so as to permit fine adjustments of said tables.

Another object of the invention is to provide an improved grinding machine, of the character described, wherein the tables are driven in opposite directions by common actuating means which has operative connection with one of said tables by a lost-motion coupling so as to permit slight adjustments in the position of the other table relative to the first table without movement of the latter.

A particular object of the invention is to provide an improved grinding machine wherein the grinding means is adapted to undergo traversing movement relative to the work by being slid transversely of its table and has adjusting means associated therewith for varying its transverse position so as to permit fine adjustments of said grinding means.

A further object of the invention is to provide an improved grinding machine having a transversely slidable carriage for supporting the grinding means and moving the same toward and away from the work, a traversing lever being connected to the carriage for imparting transverse sliding movement thereto, whereby the position of said grinding means may be rapidly varied, and said carriage including additional traversing means for making fine adjustments of its transverse position.

Still another object of the invention is to provide an improved grinding means, of the character described, wherein the traversing lever and the additional traversing means are connected to the carriage by means slidable with said carriage upon actuation of said lever, the connection of the slidable means with the carriage being such that said slidable means will remain stationary upon actuation of said traversing means and both means will move with said carriage when it is slid by the lever.

A construction designed to carry out the invention will be hereinafter decscribed together with other features of the invention.

The invention will be more readily understood from a reading of the following specification and by reference to the accompanying drawings, wherein an example of the invention is shown, and wherein:

Fig. 1 is a perspective view of a grinding machine, constructed in accordance with the invention,

Figs. 2 and 3 are plan views of the machine, illustrating adjusted positions of the same,

Fig. 4 is an enlarged, transverse, vertical, sectional view, showing the mechanism for drivingth'e tables relative to each other and the relation of the abrasive wheel carriage and traversing assemblies,

Fig. 5 is an enlarged, rear elevation of the carriage and its slide-rest,

Fig. 6 is a horizontal, cross-sectional view, taken on the line 6-6 of Fig. 5, showing the position of the main traversing assembly when the wheel is in its forwardmost grindingposition,

Fig. 7 is a view, similar to Fig. 6, showing said assembly with the wheel retracted to its rearward position,

Fig. 8 is a perspective view, showing the carriage moved forwardly of the slide-rest and the relationship of the idler pulley, and

Fig. 9 is an isometric View of the lost-motion coupling or clutch.

In the drawings, the numeral I0 designates a grinding machine Which includes an upright base ll having a horizontal bed I2 extending longitudinally across its upper end. A pair of longitudinal front and back tables l3 and M are adapted to be slidably mounted upon the bed 12 so as to be movable longitudinally of said bed and each other as shown in Figs. 2 and 3. The front table I3 is of slightly less length than the bed and its forward portion is supported by a coacting grooved way or channel l5 and a depending rib is formed at the forward longitudinal edge portions of said bed and table, respectively. As is clearly shown in Fig. 4, the channel and rib are preferably V-shaped in cross-section and an upright, longitudinal way or rail I! which 3 is made integral with the bed for supporting the rear marginal edge portion of the table [3 extends parallel to said groove and rib. A guard plate or shield I'l is secured to and depends from the back edge of the table and engages the back surface of the rail ll for preventing grindings or other foreign matter from entering between said table and rail. The back table 14 is supported in the same manner by a similar forward way or rail I8 and a similar coacting grooved way or channel l 9 and a depending rib 25, whereby the tables are mounted in parallel, independent relationship.

For sliding the tables longitudinally of the bed and each other, a drive mechanism D is provided and ircludes longitudinal gear racks or bars 2| and 22 formed on the lower surfaces of said tables and being substantially co-extensive therewith. A pinion 23, keyed upon the inner end of a transverse stub shaft 24 which extends through the forward wall or apron of the base II, has its teeth in constant mesh with the teeth of the gear rack 2!, whereby rotation of the shaft will impart longitudinal movement to the front table l3. As shown in Fig. l, the stub shaft 24 is jcurnaled in a suitable bushi g or bearing block 25 and carries a hand wheel 26 upon its forward projecting end. Below and parallel to the stub shaft, an elongate shaft 2! extends transversely of the base and is journaled in the forward and rear ably made integral with the block 25, and a similar bushing 29, re pectively. A gear 30 is keyed to the shaft 21 and is in constant mesh with the pinion 23 so as to rotate said shaft'in an opposite direction upon rotation of the stub shaft and said pinion. The shaft 21 is operatively connected to the gear rack 22 of the back table [4 by an enlarged gear wheel 3! which is journaled upon the rear end of said shaft and which is adapted to be coupled thereto by a lost-motion couping or square-jaw clutch 32 (Fig. 9). One part or element 33 of the clutch is keyed to the shaft, while the other clutch element-34 is secured to or made integral with the gear wheel 3 I. In order to permit rotation of the shaft relative to the gear wheel, each clutch element is provided with a single lateral projection or jaw 35 and these jaws are adapted to be engaged for operatively connecting said shaft and gear wheel.

Due to the provision of the clutch 33 which permits relative rotation of the shaft 21, the pinion 23 may be rotated almost one complete revolution so as to longitudinally slide the front table a slight distance without moving the back table for making fine adjustments. However, upon engagement of the clutch jaws, the back table Will he slid longitudinally in the direction opposite the direction of movement of the front table due to the gear wheel being rotated counter to the rotation of the pinion, Also, the enlarged diameters of the gear 38 and gear wheel causes the back table to be moved a greater distance than the front table upon rotation of the hand wheel and engagement of the clutch.

Longitudinal, rearwardly-inclined ways 36 are formed on the upper edge portions of the front table l3 and are adapted to adjustaby support a conventional headstock 31 and tailstock 38. The headstock has a longitudinal spindle 39 which is driven by a suitable electric motor 49 through an endless belt 4| and pulleys 42 and 43, the motor being supported by said headstock. As is clearly shown in Fig. 1, a faceplate M is carried by and rotatable with the spindle 39 and preferably includes an adjustable chuck 45 for supporting one end of the work, such as a crankshaft (not shown), so as to impart rotation thereto. The tailstock 38 is very similar to the headstock and its spindle 46 also carries a faceplate upon which an adjustable chuck 4B is mounted. Both the headstock and tailstock are slidable longitudinally of the front table I3 and are adapted to be moved toward and away from each, although shown at the ends of said table. For clamping the headstock and tailstock to the forward way 36 in adjusted positions, suitable clamping screws 49 and 50 are provided.

A transverse support or slide-rest 5| is mounted upon the back table M for slidably supporting carriage 52 and permitting the same to traverse the bed l2 and said table, as will be hereinafter explained. The carriage has an upwardly-projecting, longitudinal housing or block 53 secured to the upper surface thereof at its forward portion and a horizontal shaft or spindle E i is journaled within the housing so as to extend parallel to the table. As shown in Fig. 1, an abrasive wheel or grinding disk 55 is carried by one end of the spindle 54 and the other end of said spindle is provided with a pulley 56 so as to be rotated by an electric motor 51 which has its pulley 58 connected to the spindle pulley by an endless belt 55. The motor is suitably mounted upon the back table adjacent the slide-rest 5| and, for permitting sliding movement of the carriage while maintaining the belt 59 in driving engagement with the pulleys 5B and 58, an idler pulley I59 is pivotally connected to said slide-rest (Fig. 8).

In Fig. 2, the front table is shown at the lefthand end of the bed, while the back table is at the opposite or right-hand end of said bed so as to dispose the abrasive wheel adjacent the tailstock 38. Upon reversing the positions of the tables by rotating the hand wheel 26, the abrasive wheel is located in proximity to the headstock 31 as shown in Fig. 3. Thus, the tables are readily movable relative to each other and grinding of all parts of the work may be carried out without removing said work from the chucks 45 and 48. Due to this relative movement of the tables, it is manifest that the base II and its bed may be of relative short length so as to require a minimum amount of space without impairing the quality of, or ease of performing, the grinding operation. It is pointed out that the carriage 52 is in its forward position in Fig. 2 so as to dispose the abrasive wheel in grinding position and, when work is supported between the chucks 45 and 48, it is necessary to retract said carriage to the position shown in Fig. 2 in order to move the tables relative to each other.

As shown in Figs. 5 and 8, the slide-rest 5| is provided with a. pair of spaced, parallel ways or rails 60 and one of these rails is provided with a longitudinal guide groove or channel 6| for receiving a complementary tongue or rib 62 which depends from the underside of the carriage. The rails 50 extend transversely of the back table [4 and have their ends connected by an upright, forward cross-plate 63 and a horizontal, transverse, rear web 64 which extend longitudinally of said table (Fig. 4). A flat plate 65 is slidably supported upon the back table between the rails and is of a length slightly less than the width of said table so as to have its forward end spaced from the cross-plate 63 of the carriage. As is clearly shown in Fig. 5, the plate 65 is of a width 6! is threaded through the cross-plate 63 of the carriage for engaging the forward edge of the plate and controlling the forward position of the same. It is pointed out that the guide channel 6| and rib 62 of the slide-rest 5i are preferably V-shaped in cross-section and coact in guiding the table traversing movement of the carriage illustrated in Figs. 2 and 3. As has been explained, the idler pulley l59 maintains the belt 59 in driving engagement with the spindle pulley 56 and motor pulley 58 upon traversing movement of the carriage and an arm I60 is pivoted horizontally upon the left-hand rail 60 for supporting said idler pulley and permitting the same to swing in a vertical are upon such movement (Fig. 8). The arm I66 is constantly urged rearwardly by a tension spring l6| which connects the medial portion of said arm to the slide-rest, whereby the idler pulley is held in snug engagement with the belt 59 so as to maintain the same taut irrespective of the position of the carriage.

In order to reciprocate or slide the carriage 52 longitudinally of the rails 66 and thereby cause said carriage and the abrasive wheel 55 to traverse the back table I4 and the bed l2, a traversing assembly A is mounted upon the carriage and includes an upright, operating shaft or rod 68 journaled axially within an elongate, cylindrical housing or sleeve 69. The upper end of the rod 68 projects above the sleeve 69 and carries a hand wheel 10 which overlies and is rotatable relative to a graduated dial 1! secured to said sleeve. As is clearly shown in Fig. 4, the lower end of the sleeve extends through a vertical opening 12 formed in the carriage and is held in a fixed position by a suitable set-screw 13. A small beveled pinion 14 is carried by the lower end of the operating rod. which depends below the sleeve, and this pinion is in constant mesh with a complementary pinion 15 so as to rotate the same upon turning of the hand wheel 10 and rotation of said rod. The forward end of a horizontal rod or shaft 16 is connected within the pinion l5 and is journaled within a hanger 1'! which depends from the underside of the carriage adjacent to and rearwardly of the vertical opening 72. Thus. the shaft 76 will be rotated upon rotation of the o erating rod. Screw-threads 78 are formed on the rearwardlv-extending main portion of the shaft and engage within a screwthreaded post or block 19 projecting upwardly from the rear portion of the plate 65, whereby rotation of said shaft will cause the threads 18 to travel through the block 19 and therebv reciprocate or slide the carriage 52 longitudinally of the rails 66 of the slide-rest 5!. The plate 65 is in frictional contact with the back table and the grooves 66 so as to remain stationary and permit relative movement of the carriage, as will hereinafter be more fully explained. Manifestly, the carriage and abrasive wheel ma be moved slight distances by rotation of the hand wheel 10 due to the provision of the pinions l4 and I5 and the screw-threaded engagement of the shaft 16 with the block 19. Therefore, fine adjustments of the transverse position of the carriage and abrasive wheel are facilitated and the traversing assembly A is provided for the purpose of making such fine adjustments.

In order to quickly reciprocate or slide the carriage longitudinally of the rails 60 to the forward grinding position of the abrasive wheel (Fig. 2) or to its retracted position (Fig. 3), a traversing assembly B is mounted upon the slide-rest 5| and includes an upright, cylindrical housing or sleeve 86 having an operating shaft or rod 8| journaled axially therein and upon the upper end of which is mounted a manual lever 82. As is clearly shown in Fig. 4, the lower end of the sleeve 86 is reduced in external diameter to provide an external, radial shoulder 83 for engaging the upper surface of an annular boss 84 which is preferably made integral with the central portion of the transverse web 64 of the slide-rest. The reduced lower end of the sleeve engages within and projects through the boss 84, being held in place by a set-screw 85, and the rod 8| depends therebelow so as to receive the collar 66 of a crank arm 87. For detachably connecting the collar 86 to the rod, a pin 88 extends diametrically through said collar and rod, whereby rotation of the rod by swinging of the manual lever 82 will cause the crank arm 81 to be swung in a horizontal are about the axis of said rod. fhe crank arm is connected to the plate by a short pitman or link 89 which has one end fastened to said plate by a bolt 90 and its opposite end to said crank arm by a bolt 9*! and nut 92. Thus, swinging of the crank arm 81 b rotation of the rod Bl will cause reciprocation of the link 89 so as to slide the plate 65 longitudinally between the grooves 66 of the rails 60 and, due to the carriage 52 being connected to said plate by the screw-threaded engagement of the shaft 16 with the block 79, said carriage will he slid or reciprocated with the plate. In this manner, the traversing assembly B may be readily employed to quickly slide or reciprocate the carriage and the abrasive wheel to the forward grinding position of said wheel (Fig. 2) by forward swinging movement of said assembly (Fig. 6) and to retract the same (Fig. 3) by swinging the traversing assembly rearwardly in a counter-clockwise direction (Fig. 7). The carriage is locked in a forward or table traversing position by.continued rotation of the operating rod 8| in a clockwise direction so as to swing the crank arm 81 and link 8d a s ight distance past center or beyond their longitudinally alined positions (Fig. 6), while continued counter-clockwise rotation of said rod after said carriage has reached its retracted position will swing said crank arm and link past center and lock the carriage in said retracted position (Fig. 7).

In order to accommodate the retraction of the carriage to its rearward position, a recess 93 is formed in the center of the rear edge portion of said carriage and this recess receives the sleeve 8i) of the traversing assembly B upon such retraction. If desired, a bolt 94 may extend through and be fastened in the lower, rear portion of the right-hand rail 60 by suitable nuts 95 and as (Fig. 5) so as to project laterally inward thereof for limiting the over-throw or path-center swinging movements of the crank arm 3? and link 38. As has been hereinbefore pointed out. the traversing assembly A is provided for making fine adjustments of the transverse or table traversing position of the carriage and projection and retraction of said carriage are preferably accomplished by means of the traversing assembly B. As shown in Fig. 4, the forward position of the plate 65 is controlled by the set-screw 67 which projects through the crossplate 63 and forward movement of the carriage by the assembly B is limited by the adjustment of said set-screw. Any additional adjustments of the carriage that might be necessary are made by manipulation of the assembly A. Due to the assembly B being mounted upon the slide-rest, said assembly and the plate 65 remain stationary upon movement of the carriage upon manipulation of the assembly A. Also, the locking of the carriage in its forward position by the postcenter or over-throw of the crank arm and link (Fig. 6) positively prevents sliding of the plate 65 upon adjustment of the carriage position by the assembly A, because said plate is confined between the set-screw 6'1 and said locked crank arm and link.

The work to be ground or finished is supported between the chucks 45 and 48 upon adjustment of the headstock 31 and tailstock 38 relative to the front table I3. During this positioning of the work,-the carriage 52 is in its retracted position so as to retract the abrasive wheel 55 as shown in Figs. 3 and 7 and this retraction is accomplished by counterclockwise rotation and swinging of the traversing assembly B (Fig. 7). The hand wheel 25 is then rotated so as to actuate the drive mechanism D and drive or slide the front and back tables relative to each other, thereby moving the abrasive wheel longitudinally to the desired position relative to the work. Due to the provision of the clutch 34, the front table may be moved a slight distance in either direction independent of and relative to the back table for making fine longitudinal adjustments of the work relative to the abrasive wheel. The carriage 52 is then slid forwardly as shown in Fig. 2 by manipulation of the traversing assembly B (Fig. 6) so as to dispose the periphery of the abrasive wheel in close proximity to the work. With the wheel in its forward position, fine transverse adjustments of the same may be made by means of the traversing assembly A. Of course, the wheel may be fed gradually forward by the assembly A and, if a straight member or shaft is being worked upon, the tables may be moved longitudinally relative to each other so as to move the work longitudinally of said wheel without fully retracting the carriage. However, when the work is of irregular shape, such as a crankshaft, the carriage is retracted to its rearward position by the assembly B before the tables are moved longitudinally of each other for presenting another portion of said work to said wheel. Upon this repositioning of the work, the abrasive wheel is again moved to its forward position by manipulating the assembly B so as to slide the carriage forwardly of the back table and any fine adjustments of the transverse position of said wheel that might be necessary are made by means of the assembly A.

It is pointed out that the forward movement of the carriage by the assembly B is limited by the engagement of the plate 65'with the setscrew 67 (Fig. 4) and that movement of said plate upon adjustment of the transverse position of the carriage by the assembly A is prevented by the lozking of the assembly B due to the crank arm 81 and line 89 being swung past center as illustrated in Fig. 6. Attention is again directed to the fact that the provision of two longitudinally movable tables makes it possible for the base H of the grinding machine If! to be of relatively short length without impairing the quality of the grinding operation, prolonging the time required for the same or making it more difiicult to perform suchoperation. The carriage and abrasive wheel may be quickly retracted and projected by means of the traversing assembly B and fine adjustments of the transverse position of said wheel while the same is in its projected position may be made by means of the traversing assembly A. Since the front and back tables are moved longitudinally of each other by a common aztuating means or drive mechanism D, the same may be quickly moved from the position shown in Fig. 2 to the position shown in Fig. 3 or to any intermediate relationship and the clutch 34 of the mechanism permits fine longitudinal adjustments of the abrasive wheel relative to the work whenever desirable or necessary.

The foregoing description of the invention is explanatory thereof and various changes in the size, shape and materials, as well as in the details of the illustrated construction may be made, within the scope of the appended claims, without departing from the spirit of the invention.

What I claim and desire to secure by Letters Patent is:

1. A grinding machine including, a base, a pair of tables slidably mounted upon the base and adapted to he slid longitudinally of each other, grinding means mounted on one table and adapted to undergo movement transversely of the other table, and actuating means for sliding the tables longitudinally of each other, the actuating means having a lost-motion connection with one table and a direct connection with the other table whereby the latter table may be slid longitudinally a slight distance in either direction independent of and relative to the former table.

2. A grinding machine as set forth in claim 1 wherein the actuating means consists of a gear drive mechanism.

3. A grinding machine including, a base, a pair of tables slidably mounted upon the base and adapted to be slid longitudinally of each other, abrasive means mounted on one table, a gear drive mechanism having connection with each table for sliding the same longitudinally of each other, the mechanism being directly connected with one table, and a lost-motion coupling connecting the other table with said mechanism, whereby said first table may be slid slight distances longitudinally and independently of said second table.

4. A grinding machine as set forth in claim 3 including, a gear rack carried by each table, the gear drive mechanism having a gear wheel meshing with each gear rack and adapted to be rotated for driving the racks to longitudinally slide the tables, the lost-motion coupling connecting one gear wheel to the remainder of said mechanism.

RAYMOND A. JOHNSON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,101,383 Asbridge Dec. 7, 1937 1,881,984., Van Norman Oct. 11, 1932 1,803,807 Norton May 5, 1931 1,726,247 Stoner Aug. 2'7, 1929

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