US2093694A - Grading machine - Google Patents

Description

Sept. 21, 1937. J. w. JOHNSTON- GRADING MACHINE 3 Sheets-Sheet l Filed May 8, 1936 Sept. 21, 1937. J. w. JOHNSTON GRADING MACHINE U Wu n Hm w 3 I Filed May 8,

' fi/ZM Se t. 21, 1937. J. w. JOHNSTON 2,093,694

' GRADING MACHINE Filed May 8, 1936 3 Sheets-Sheet 5 I I'D/EFFECT: Zfl im/szfon M, Zia

Patented Sept. 21, 1937 UNH'E S'i'ATEfi Zdhti A'iilti'f rits 8 Claims. (Cl. 101-413) This invention relates to grading machines of the kind which grade blanks or pieces of sheet material, such as leather, in accordance with the thickness of the thinnest spot as determined by the detector.

The invention consists in certain improvements and modifications in the wellknown Nichols grading machines of the kind shown in a number of patents to Elmer P. Nichols, Leander A. Cogswell and James W. Johnston, a characteristic example of which will be found in the Nichols Patent No. 1,130,321 dated March 2, 1915.

The principal object of the invention is to adapt a grading machine of thev kind indicated to the grading of blanks of indeterminate length and of greater length than has heretofore been possible. To this end I have devised mechanism for actuating the marking or stamping device by the passage of the rear or trailing end of a blank passing through the maclL'ne, instead of by the advance or leading end of the blank as in machines heretofore constructed, with the result that regardless of the length of the blank the marking mechanism will not be actuated until 5 the entire blank has been measured and the trailing end of the blank has passed clear of the detecting and measuring device.

Although the invention is primarily intended for grading long blanks or strips, which are too 30 long to be graded in a regular Nichols grading machine, it may also be usefully employed in grading short blanks if it is desired to mark or stamp the blanks near the trailing end thereof and a given distance therefrom, instead of near the leading end thereof.

In the accompanying drawings, which illustrate such parts of a Nichols grading machine as are necessary to an understanding of the application of the present invention,

40 Fig. 1 is a side elevation of a grading machine embodying the invention;

Fig. 2 is a top plan View of parts of the machine shown in Fig. 1; and

Fig. 3 is an enlarged detail partly in elevation 45 and partly in lonigtudinal vertical section showing certain of the trips hereinafter described.

The machine contains the usual pair of detecting or measuring rolls ill and I! (Fig. 1) be 50 tween which the blanks are fed forwardly in the direction of the arrow (Fig. 2) into position beneath a marking wheel l2, which is automatically adjusted to register the thinnest spot of the blank as found by the detecting rolls and is 55 then automatically reciprocated vertically so as to strike against and mark the top side of the blank.

During the passage of the blank. between the detecting rolls iii and ii the thickness of its thinnest part is detected and measured and the 5 lower roll ii, which moves up and down in response to variations in thickness of the blank, acts through the usual setting mechanism to adjust the marking Wheel 52 to accord with the thickness of the thinnest part of the blank as determined by the detecting rolls. The periphery of the marking wheel 52 is provided as usual with types to indicated numerals or characters designating different thickness or grades, and during the passage of the blank between the detecting 1 rolls the lower roll actuates the usual setting mechanism automatically to adjust the marking wheel angularly so as to bring the appropriate type into marking position.

The frame of the machine as usual is pro- 20 vided with a shelf or table E3 on which the blanks are successively fed forwardly, either manually or automatically, to the detecting and measuring rolls l8 and il, which are continuously rotated. The upper roll it is journals-d in normally fixed bearings boxes and is continuously driven through gearings by the continuously rotating main drive shaft i l of the machine. The two measuring rolls are provided at their ends with intermeshing gears so that the upper roll drives the lower roll thereby positively to feed the blank forwardly into position between the presser bar it and a continuously traveling feed chain it. The feed chain it is driven by the main shaft i through the usual gearing and after the rear end of the blank leaves the measuring rolls ii) and H the forward movement of the blank is continue-d by the feed chain it until the rear end of the blank is about opposite the marking wheel i2.

When the advance end of a blank being fed into the machine emerges from between the measuring rolls ill and ii it operates a start grading trip arm ll (Fig. 2) thereby causing the pawl or detent l8 (Fig. l) to engage the usual ratchet Wheel 19 which constitutes part of the setting mechanism by which the lower measuring roll it adjusts the marking wheel l2. From the time the leading end of the blank actuates the start grading trip ll until just as its trailing end is about to pass the measuring rolls l0 and ii, during which time the pawl i8 will remain in engagement with its teeth on ratchet wheel l9, the pawl 21 will be disengaged from its teeth on ratchet Wheel l9. Consequently the measurement of the blank for the thinnest spot as determined by the detecting rolls I (l and I I will be preserved and will be transmitted to the marking wheel I2 in the manner well known in machines of this type.

Each blank is fed forward on table I3 beneath the usual pivoted gate which, at the time the blank first enters the nip of rolls I0 and II, is held in elevated position by a link El and lever 22, the latter being fulcrumed at 23 on the frame of the machine and having a downwardly extending arm carrying a cam following roll 28, which cooperates with a cam 24 forming part of or fixed to the start grading trip arm I I. When the leading end of the blank emerges from between the detecting rolls II and I I and swings the trip arm H to the left on its pivot 25 (Fig. 2) the cam 24 is also swung to the left and thereby raises the left-hand end of the lever 22 and lowers the right-hand end of lever 22 thus permitting the gate 20 to rest on top of the blank. When the trailing end of the advancing blank passes out from under the gate 26 the gate falls to the table (which is permitted by the slotted connection between link 2| and lever 22) and acts through link 26 (Fig. 1) to engage the usual stop grading pawl 21 with ratchet wheel I9. The ratchet wheel I9 is now locked by the pawls I B and 21 against movement in either direction and consequently the marking wheel I2 is similarly locked in its grade registering adjustment against rotation in either direction. The engagement of the stop grading pawl 21 with ratchet wheel I9 occurs just before the rear end of the blank passes the detecting rolls I0 and II so that the blank will have been measured throughout substantially its whole length.

The cam following roll 28 of the lever 22 is as usual disposed beneath a short arm 29 fast on a rock shaft 38. Fixed to the rock shaft 30 near the middle of the machine is also a longitudinally extending arm 3| to which is affixed the usual weighted shoe 32 (Figs. 2 and 3). The shoe 32 continues to rest upon the top of the blank after the blank has moved forwardly out of engagement with the trip lever IT and after the latter has been restored to its normal position by its usual spring. Thus the engagement of the shoe 32 with the top of the blank maintains the pawl I8 in engagement with ratchet wheel I9 until the rear end of the blank has passed out from under the shoe 32, whereupon the latter falls and disengages the detent I8 from ratchet wheel I9. Simultaneously, when the shoe 32 drops off from the end of the blank, arm 29 on rock shaft 30 is swung downwardly and thereby acts through lever 22 and links 2I and 26 to open the gate 20 and disengage the pawl 27. Thus both locks, I8 and 21, are unlocked to release the marking mechanism for a new adjustment by a succeeding blank, as the trailing end of each blank passes the shoe 32.

The shoe 32 differs from that in the usual Nichols grading machine in that its two feet 33, which straddle the feed chain I6, are longer and extend farther toward the marking wheel l2.

The marking wheel I2 is fixed to a shaft journaled as usual in a bearing at the lower end of the vertically movable slide or plunger 34, which is strongly and yieldingly urged downward by the usual arm 35 actuated by spring 35*. The plunger 34 is held in elevated position by the usual cam, not shown, mounted on the inner end of a shaft 36 (Fig. 1). Shaft 36 is connected through a train of gearing 31 with a gear 38, upon the inner face of which is formed one clutch member of a one-revolution-and-stop clutch, the gear 38 being splined to and axially movable upon a stud shaft 39 (Fig. l). The other clutch member of this one-revolution-and-stop clutch is provided on the inner face of gear 40 which is rotatably mounted on shaft 39 and is continuously driven by a gear M on shaft I4.

The clutch gear 38 is controlled and operated by the usual shipper member 42 which is pivotally mounted at 43 on the frame of the machine. This shipper member, as usual, carries a springpressed latch 44 (Fig. 1) and is normally maintained in a position to hold the gear clutch member 38 retracted by means of the usual spring 45 (Fi 2).

When the shipper member 42 is swung toward the right it is disengaged from the gear clutch member 38 and the latter is thrown forwardly by the usual spring, not shown, into engagement with the gear clutch member 40, whereupon the clutch member 38 makes one revolution, at the end of which it is again retracted and stopped by the shipper member 42. This rotation of the clutch member 38 acts through the above described train of gearing to impart a single revolution to the shaft 36 during which a roller 46 projecting from one face of the gear on shaft 36 acts through a lever 41 to reciprocate the latch slide 44 for the purpose hereinafter explained.

The construction and mode of operation of the machine as thus far described may be substantially the same as that of the already wellknown Nichols grading machines.

The present invention has to do primarily with the control and operation of the marking wheel In grading machines of this kind as heretofore constructed the mechanism for stamping or marking the blank has been set in operation by a trip actuated by the leading end of the advancing blank. This has been satisfactory because these grading machines have hitherto been used for grading comparatively short blanks such as soles, taps or heel lifts, and by the time the leading end of such a blank actuates the trip for operating the marking mechanism, the blank has been com pletely measured and the rear or trailing end of the blank has passed clear of the measuring rolls Ill and II, and the marking wheel I2 has been adjusted in accordance with the final measurement or detection of the entire blank for its thinnest spot.

If, however, it were attempted to use the previous grading machines for grading long blanks such, for example, as strips of leather whose length exceeds the distance between the measuring rolls I3 and II and the stamp operating trip, it is obvious that the marking wheel I2 would be adjusted only in accordance with that part of the blank which has already passed the measuring rolls II], II and would therefore not indicate the proper grade of the blank as a whole, nor any measurement of that part of the blank which has not yet passed the measuring rolls. Moreover, the pawl 21 would still be disengaged from ratchet wheel I9 so long as the gate 20 rests on the incoming blank and consequently the ratchet r swing the shipper member of the trailing end of the blank after the blankhas been measured for its full length and the marking wheel 12 has been adjusted in accordance with said full length measurement and after the trailing end of the blank has passed the gate 20 and the measuring rolls ill and ii.

In carrying out this invention an arm 48 (Fig. 1) positioned to cooperate with the lower end of latch slide M is fixed to one end of a rock shaft 29 which is jpurnaled in bearings on the frame of the machine underneath the path of the blanks and extends across the machine from side to side as indicated by dotted lines in Fig. 2.

The rotative movement of the rock shaft 49 and arm 48 to the left, that is, in a counter-clockwise direction (Fig. 1), will swing the upper end of arm 48 past the beveled end of the latch slide id, the latter yielding upwardly to permit the arm 48 to pass, and as soon as the arm 48 moves past the latch slide M the latter will be again projected downwardly by its usual spring into the path of the end of arm 5.8. If arm M is then swung to the right, that is, in a clockwise direction, it will engage the straight side of latch slide id and 42 with it far enough to effect the engagement of clutch member 38 with the clutch member it (Fig. 2). The resulting rotation of shaft 35 will then act through roller 46 and lever ll to retract the latch slide it upwardly, thereby disengaging the latch at from the arm 48 and permitting the spring 15 to restore the shipper member 42 to its normal position before the clutch member 38 completes its single revolution and in time to retract the clutch member 38 as it completes said single revolution.

The single rotation thus imparted to the shaft 35 acts through the usual cam on said shaft to raise the slide or plunger 3Q against the pressure of spring 35 and then to release the plunger in the usual way, whereupon the spring 35 and arm 35 force the plunger 34 downwardly causing the marking wheel IE to strike the blank.

It will be observed that this stamping or marking operation of the plunger 34 is effected only by the movement of arm 48 toward the right (Fig. 1).

The frame of the machine includes the usual bed plate 5t (Figs. 2 and 3) which extends from the measuring rolls if! and ii to apoint just beyond the marking wheel l2 so as to support the blank where it is struck by the marking wheel l2. Fixed to the rock shaft 43, which extends underneath the plate 5b, is a trip arm 51 (Figs. 1 and 3) projecting upwardly through a slot 5?. in the bed plate 50 with its upper end normally occupying a position in the path of the blanks as they move forward over plate 50 in the direction indicated by the arrow in Fig. 3. As each blank moving forward from the measuring rolls engages the upper end of trip arm 5! it swings the trip arm 5| to the left and acts through rock shaft 49 to swing arm 48 (Fig. 1) into a position behind the latch slide 44, as already described. The trip arm 51 remains in this displaced position so long as it is held down by the passing blank and until the trailing end of the blank passes clear of the end of the trip arm 51, whereupon a spring 53 (Figs. 1 and 2) restores the trip arm and parts connected therewith to their normal positions. The return movement of the arm 48 acts, as above described, to operate the shipper member 42 and thereby causes the marking wheel IE to strike the blank.

Directly above the trip arm 5| there is a presser foot 54 which is pivotally mounted at 56 upon a bracket 56 forming part of the frame of the machine. Between the presser foot 5 s and the bracket 5'6 is arranged a coil spring 5i, one end of which abuts against the presser foot 5 5 and the other end of which abuts against a thimble 53 loosely fitted upon the lower end of a screw 59. The screw 59 occupies a threaded hole in the bracket 5% so that it can be adjusted vertically thereby to regulate the pressure of the spring iii. A check nut til holds the screw in adjusted position.

As the forward end of each blank engages and swings aside the trip arm 55 the lower end of the presser foot 5t rides up on top of the blank and serves to hold the blank down on the bed plate against the tendency of spring 53 (Fig. 1) acting through arm es, rock shaft 49 and trip arm 5| to lift the blank.

The effective grading action of the machine begins when the forward end of each emerges from between the measuring rolls [8 and H and operates the start grading trip H, and the grading action ends when the gate to falls off from the rear end of the blank and sets the stop grading pawl 21 into engagement with the ratchet wheel l9.

It will also be understood that while the shoe 32 (Figs. 2 and 3) rests on the passing blank, the arm 3! will be supported in elevated position by the blank and will also hold in elevated position the arm 65, which is fixed to rock shaft 35], and the depending weighted rod .52, which controls the tail piece of pawl l3 and permits the pawl i8 to remain in engagement with the ratchet wheel is. In this position the angular adjustment of the marking wheel 1?. to accord with successively thinner spots in the blank, as determined by the detecting rolls l9 and ii, will be preserved. But when the shoe 32 drops off from the trailing end of the blank the weighted rod 62 will move downwardly and disengage pawl "3 from ratchet wheel 19, and simultaneously the pawl Zl will be disengaged from the ratchet wheel 59.

As will be observed in Fig. 3 the trip arm 5! and the weighted shoe 32 are relatively so disposed that the rear or trailing end of the blank first passes clear of the arm 5! and thereafter passes out from under the shoe 32. It is during the interval between these two happenings that the marking wheel is operated to stamp the blank.

The shoe 32 and the arm 5! are both positioned fairly close to the marking wheel so that all blanks passing through the machine, regardless of their length, are marked comparatively near, and the same distance from, their rear or trailing ends.

I claim:

1. A grading machine comprising detecting mechanism for measuring successive blanks of stock according to thickness, adjustable marking mechanism responsive to the detecting mechanism, control mechanism constructed and arranged to be operated by the trailing end of a blank passing through the machine for actuating the marking mechanism to mark the blank, and means for holding the marking mechanism in adjusted position until after the operation of the control mechanism.

2. A grading machine comprising detecting mechanism for measuring successive blanks of stock according to thickness, adjustable marking mechanism responsive to the detecting mechblank anism, a movable trip normally in the path of a blank passing through the machine for actuating the marking mechanism, said trip being constructed and arranged to be displaced and to be held displaced by the blank without actuating the marking mechanism so long as it is engaged by the blank and to cause the operation of the marking mechanism when the trailing end of the blank passes the trip and releases it to return to its normal position, and means for holding the marking mechanism in adjusted position until after the release of said trip.

3. A grading machine comprising detecting mechanism for measuring successive blanks of stock according to thickness, adjustable marking mechanism responsive to the detecting mechanism, means controlled by a blank passing through the machine to lock the marking mech anism in its position of adjustment as determined by the detecting mechanism, means constructed and arranged to be operated by the trailing end of the blank to unlock the marking mechanism, control mechanism constructed and arranged to be operated by the trailing end of the blank for actuating the marking mechanism to mark the blank before the grade registering adjustment of the marking mechanism is unlocked, and means for holding the marking mechanism in adjusted position until after the operation of the control mechanism.

4. A grading machine comprising detecting mechanism for measuring successive blanks of stock according to thickness, adjustable marking mechanism responsive to the detecting mechanism, a yielding spring-pressed trip normally projecting upward into the path of a blank passing through the machine, said trip being adapted to be swung downwardly and to be held down by be blank without actuating the marking mechanism so long as it is engaged by the blank and constructed and arranged to eiTect the operation of the marking mechanism when the trailing end of the blank passes the trip releases it to return to its normal position, and a yielding presser member adapted to engage the upper side of the blank to hold the blank down against the tendency of the trip to lift it, and means for holding the marking mechanism in adjusted position until after the release of said trip.

5. A grading machine comprising detecting mechanism for measuring successive blanks of stock according to thickness, adjustable marking mechanism responsive to the detecting mechanism, a rock shaft below the path of the blank, a trip arm fixed to the rock shaft and normally extending upwardly into the path of the blank and adapted when pushed aside by the blank to rotate the rock shaft, a spring tending to urge the trip toward normal position, mechanism controlled by the return rotation of the rock shaft under the influence of said spring when the trailing end of the blank passes clear of the trip to actuate the marking mechanism to mark the blank, and means for holding the marking mechanism in adjusted position until after the release of said trip.

6. A grading machine comprising detecting mechanism for measuring successive blanks of stock according to thickness, adjustable marking mechanism responsive to the detecting mechanism, a rock shaft below the path of the blank, a trip arm fixed to the rock shaft and normally extending upwardly into the path of the blank and adapted when pushed aside by the blank to rotate the rock shaft, a spring tending to urge the trip toward normal position, mechanism controlled by the return rotation of the rock shaft under the influence of said spring when the trailing end of the blank passes clear of the trip to actuate the marking mechanism to mark the blank, a spring actuated presser foot adapted to rest on the upper side of the blank and hold the blank down against the tendency of the trip to lift it, and means for holding the marking mechanism in adjusted position until after the release of said trip.

7. A grading machine comprising detecting mechanism for measuring successive blanks according to thickness, adjustable grading mechanism responsive to the detecting mechanism, control mechanism constructed and arranged to be operated by the trailing end of a measured blank passing through the machine for actuating the grading mechanism, and means operative to prevent the resetting of the grading mechanism until after the measured blank has been graded.

8. A grading machine comprising detecting mechanism for measuring successive blanks according to thickness, mechanism for grading said blanks in accordance with the measured thickness, transmission mechanism operative to set the grading mechanism in accordance with the minimum measurement detected by the detecting mechanism, control mechanism constructed and arranged to be operated by the trailing end of a measured blank for actuating the grading mechanism, and means for holding the transmission mechanism in adjusted position until after the operation of the control mechanism.

JAMES W. JOHNSTON.

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