US3456465A - Press feeder - Google Patents

Description

July 22, 1969 Q ET AL PRES S FEEDER 3 Sheets-Sheet 1 Filed Dec. 4. 1967 Fig.

INVENTORS 0E, 24x Mm FIRM July 22, 1969 o. E. PAX ET AL PRESS FEEDER 5 Sheets-Sheet 2 Filed Dec. 4, 1967 Fig.4

INVENTORS 0E p,qx 4N0 BY Fig. 3

United States Patent 3,456,465 PRESS FEEDER Oscar E. Pax, RR. 5, Box 400-A, Celina, Ohio 45822, and Francis J. Pax, 624 Plum Drive, Goldwater, Ohio Filed Dec. 4, 1967, Ser. No. 687,687 Int. Cl. B21d 55/00, 43/02 U.S. Cl. 72-4 Claims ABSTRACT OF THE DISCLOSURE tivity such that in the event of undue resistance to feeding, the entire press is stopped to prevent damage to the die or the press itself. Further, the invention contemplates the use of a roll feeding mechanism which does not require highly precise mounting with respect to the press nor extremely accurate positioning with respect to the die being fed by the feeder and further makes the feeder a flexible device which may be mounted in nearly any position with respect to the press since there are no direct mechanical connections thereto, yet at the same time the operation is precisely controlled in accordance with movement of the press throughout its cycle.

This invention is directed to a novel form of roll feeder which provides extremely rapid feeding of strip material into a press for operation on such material by the press, and is intended to perform such feeding operation in increments such as is required in feeding a progressive die, and since extreme accuracy is provided the step by step or incremental feeding will in most cases be sufficiently accurate that pilot means are not required in the die itself for most applications.

An object of the invention is to provide a feeding mechanism which is extremely flexible, relatively simple in construction, highly accurate in positoning, and of such high speed that the operation thereof approaches opera tions which may be performed by machines which are extremely expensive and designed specifically for individual jobs.

A particular object of the invention is to provide a feeder which in and of itself can be provided as an attachment for the usual type of press, and in this area it is contemplated that the metal working field is probably the largest field in which the invention finds application, although obviously other materials which are operated upon in manner similar to that of a metal working or punch press may be equally as satisfactorily handled hereby.

A further object of the invention is to provide a roll feeder in which extremely high pressures may be exerted on the strip material being fed so that accuracy is produced and yet extreme sensitivity is incorporated so that where damage might be otherwise the result, it will not take place in the concept hereof.

Another object of the invention is to provide a novel arrangement of the respective parts so that extreme fiexibility for use thereof is provided, and adjustment for various amounts of feed is likewise available, which together with the extremely high speed potential will produce a final result which is desirable in all phases of metal Working where a punch press or the like is used.

Other and further objects of the invention will be 3,456,465 Patented July 22, 1969 understood from a consideration of the specification appended hereto and disclosed in the drawings wherein:

FIGURE 1 is a side elevation of a press, somewhat diagrammatically disclosed, with the feeding device of this invention in place and various elements in relation to it.

FIGURE 2 is a front elevation of the feeding device itself, with certain portions in cross section and largely in elevation.

FIGURE 3 is an end elevation of the feeding device.

FIGURE 4 is a sectional view of the device in FIG- URE 3 taken about on the line 4--4 of FIGURE 3 looking in the direction of the arrows.

FIGURE 5 is an enlarged fragmentary sectional view, illustrating the valving stystem in the hydraulic piston and cylinder units.

FIGURE 6 is a fragmentary view partly in section showing the air-hydraulic booster arrangement for the feed roll of the feeding mechanism.

FIGURE 7 is a diagrammatic circuit disclosure to illustrate the press clutch circuit.

FIGURE 8 is a diagrammatic circuit view showing the roll lifter circuit.

Referring now to FIGURE 1, the invention hereof is disclosed as being arranged in conjunction with a punch press generally denoted 1, the feeding device or feeder generally denoted at 2, with the hydraulic system for such feeder in the area denoted 3, and the controls for the feeder itself in the area generally indicated at 4.

Turning first of all to a description of the press 1, as a whole, it is noted that this may be of any generally conventional form having the usual main frame 5 which includes a bed 6 thereon upon which a die not illustrated may be supported, as to the lower section thereof. A ram 7 arranged to move upwardly and downwardly above the bed and support at its lower extremity the other section of the die, is in turn connected to an arm 8 of a crankshaft 9 by a connecting rod, the crankshaft 9 carrying a flywheel 10 thereon which will, in this particular instance, be illustrated as having circumferential teeth thereon for drive purposes. It should be noted as will be clear to those skilled in the art, that a suitable clutch arrangement (not shown) is provided as customary to effect the drive of the crankshaft 9 and for this purpose an air clutch is most suitable in the surroundings under consideration.

Turning now to a description of the feeder or feeding mechanism itself, which is denoted at 2, and which is further illustrated in detail in FIGURE 2, it will be noted that this feeder includes a base 11 suitably supported so as to extend to one side of the press frame 5 by the members 12, the base 11 for the purposes hereof being described as a flat plate and having extending upwardly therefrom the side frames 13 and 14.

The side frames 13 and 14 are designed to support a pair of rolls in a manner illustrated in greater detail in FIGURES 3 and 4, upon a lower shaft 15 for a roll 16-, and an upper shaft 17 for the upper roll 18.

The shaft 15 and the roll mounted thereon are carried in a suitable roller bearing such as 19, with the upper shaft 17 being carried in an adjustable bearing member 20.

It will be understood that the end opposite the side frame 14, namely side frame 13, will be formed substantially identically and fixed suitably to the base 11 with the bearings for that side frame being of substantially the same arrangement as has just been described.

On the end of the shaft 15, as shown in FIGURE 4-, there is positioned a brake unit 21 and as illustrated in FIGURE 3 comprises a fixed shoe 22 extending around a drum 23 at the lower half thereof, there being a movable shoe 24 pivoted at 25 to the shoe 22.

Suitable braking force may be applied to the drum 23 by the provision of an adjustable member 26 operating through a spring 27 on the ear 28.

Since the drum 23 is keyed as at 29 to the shaft 15, restraint transferred to the drum by the brake mechanism just described will in turn be transmitted to the shaft and as will presently be explained in turn to the respective rolls 16 and 18.

Suitably keyed to the shaft 15 as illustrated in FIG- URE 4,is a gear 30, said gear 30 in turn meshing with a further gear 31 mounted and keyed to the shaft 17.

'It will be apparent therefore that the rolls 16 and 18 are simultaneously driven by the interengaging action of the gears and of course in the opposite direction so as to cause material inserted between the rolls to be carried therethrough in a manner to be subsequently described in detail.

At the end opposite that illustrated in FIGURES 3 vand 4, the rolls 16 and 18 are mounted in substantially identical bearing members 19 and 20, with the shaft 15 extending outwardly beyond the same, and having a gear 3-1 mounted thereon for driving engagement by a clutch unit 32, this clutch unit 32 being a well known cam type of clutch which will operate upon rotation in one direction but will not impart drive force when rotation is effected in the opposite direction.

The gear 31 which normally transmits drive motion to the clutch 32 and thence to the shaft 15, is in turn engaged with a rank 33 suitably guidingly arranged adjacent the end fram 13 to maintain such engagement with the gear 31, and in turn driven by hydraulic piston and cylinder instrumentalities to be described subsequently in detail.

Since the upper roll 18 without more, would be free to move upwardly under expansive action of springs 18;: as carried in the bearings such as described, and since it is desired to be able to exert a downward pressure on the roll 18 of substantial amount, suitable piston and cylinder units of any preferred form, not shown in detail but suggested at 34 and 35 are provided, wherein the piston of such unit directs force downwardly on the upper surfaces 20a of the bearing members 20 at the ends of the roll 18 when suitable hydraulic force is directed thereto by an air-hydraulic booster unit generally denoted 36, and illustrated more particularly in FIGURE 6.

This air-hydraulic booster unit 36 as shown, includes a body 37, having a chamber 38 therein connected by suitable fluid connections 39 and 40, comprising piping to the piston and cylinder units 35 and 34 respectively.

Above the body 37, a cylinder member 41 is shown as being suitably fastened to the body 37, and having the piston member 42 therein which includes a ram member 43 extending downwardly into the chamber 38, and for purposes of illustration and description having a diameter of about The piston 42 has an area of 3.1416 sq. in. and when 100 lbs. per square inch of air pressure is applied to the head 44 and specifically in the passage 45 therein, 314.16 lbs. of force is applied to the ram 43.

The ultimate hydraulic pressure developed thereby is 711.09 lbs. per sq. in. and this in turn is transmitted to the piston and cylinder units 34 and 35 which greatly multiplies the pressure applied thereto and in turn thus applied to the roll 18 by the arrangement heretofore described.

The actual method of controlling such application and pressure will be explained in detail when the cycle of operation is set forth after description of the hydraulic drive for the feeder itself is completed.

Referirng now to the hydraulic drive arragnement generally in the area indicated at 3 in FIGRUE 1, there is illustrated a slave or first piston and cylinder set 46 which includes a cylinder 47 in which a piston 48- is positioned, the piston 48 in turn being connected to a piston rod 49 which piston rod has affixed thereto the rack 33 previously mentioned, the rack 33 being at the lower end of the piston rod 49, and said piston rod extending through the rod cap 50.

A cap 51 is positioned at the upper end of the cylinder 47 which cap is connected to a pressure valve 52 to be described in some further detail subsequently.

A supply tank 53 is arranged adjacent the piston and cylinder unit 46, both units being fixed with respect to the feeding mechanism illustrated in FIGURE 2 so that the rack 33 is properly aligned with relation thereto and a driving force may be transmitted by said rod as heretofore suggested.

The supply tank 53 is provided to receive fluid from the upper end of the cylinder through cap 51 since the piston 48 is arranged to have slightly less travel than a piston and cylinder unit with which it is connected and by which it is driven as described later and for purposes which will also be explained.

The supply tank 53 is connected at its ends to the ends of the piston and cylinder unit 46 by valve mechanisms such as illustrated in FIGURE 5, which valve mechanisms (there being one for each cap and 51) are arranged so that excess fluid directed at the cap 50 for example upon an upward movement of the piston 48, will pass through the valve 56 into the storage tank 53, at the same time taking enough fluid out of the storage tank 53 at the other cap 51 to compensate for movement of the piston if necessary.

Conversely when the piston 48 moves to the bottom of its stroke which is limited by abutment of the end of the rack 33 with a stop 33a, excess fluid there will be delivered through a valve 54 to the tank 53 and withdrawn from the tank 53 through a valve 55 if necessary, all

these valves being ball check valves as will be apparent.

The slave or first piston and cylinder set just described, is arranged to be driven by a power piston and cylinder set now to be described, said power set being denoted generally, having a cylinder 61 and a piston 62 therein connected to a piston rod 63. The cylinder 61 is provided with a cap 64 pivotally mounted at 65 onto the press frame by a bracket 66.

Connection of the piston and cylinder 60 just described with the slave piston and cylinder set 46 previously described, is elfected by means of the hydraulic hose 67 extending from the rod cap 68 of the set 60 to the rod cap 50 of the set 46.

Similarly, a hydraulic hose 69 extends from the cap 64 to the cap 51 previously mentioned.

The power and slave hydraulic piston and cylinder sets are intended to impart varying strokes to the rack 33 to in turn regulate the quantity of material such as strip material fed between the rolls 16 and 18, and since timing of such drive is of importance, the piston rod 63 of the power set 60 is connected to a rotation to linear drive arrangement indicated at 70 and including a member 71 which is in this instance a round unit having a slot 72 across the axis in which slot 72 the pivot 73 is positioned and in turn affixed to a block moving in the slot 72 threadedly engaged with an adjusting screw 74 so that the pivot point 73 may be moved toward and from the axis of the member 70, the member 70 in turn being fixed to the crankshaft 9 of the flywheel 10.

In view of this arrangement, rotation of the drive gear 10 will obviously carry the pivot 73 in circular motion and impart linear motion to the piston rod 63 so that corresponding motion of the piston 62 thereon will in turn be translated to the piston 48 in the slave set 46.

Since it is contemplated that the roll 18 will be periodically moved toward the roll 16 to grasp in feeding engagement, a strip of material introduced therebetween, control for the roll pressure arrangement illustrated in FIGURE 6 is provided in the form of a cam 75 of a switch unit illustrated in FIGURE 1 somewhat diagrammatically, the cam 75 being mounted on an axis 76 and driven from the shaft 9 in a one-to-one ratio. The cam 75 includes an adjustable cam element 77 which by rotation with respect to the cam 75 will provide for interrupting action with respect to a switch illustrated at 78.

The switch 78 is part of a so-called roll lifter circuit shown in FIGURE 8 as including the contacts 79 and 80 to be completed by the motion of an arm 81 having contacts thereon, the arm pivotally arranged so that a roller 82 at the end will ride on the cam 75 and specifically the portion 83 thereof to effect completion of the circuit.

The circuit contacts 79 and 80 extend to corresponding electric lines 85 and 86, line 85 passing through a switch 87 and completing a circuit with a suitable supply of electricity at 88 to operate a solenoid 89, and permit air pressure to be directed through a valve indicated at 90, which valve in turn is connected by a suitable pipe suggested at 91 to the opening 45 in the air hydraulic booster 36 previously described in detail.

It will be apparent from the foregoing that when the contact is made and the circuit completed, solenoid 89 is actuated and the air will be supplied to the air hydraulic booster 36 and in turn the hydraulic pressure generated thereby will be exerted on the floating bearings 20 of the feeder unit and thus to the roll 18 thereof to in turn transmit the necessary feeding engagement of such roll with material inserted between that roll and the roll 16.

Since during this circuit completion the gear is driving the shaft 9 to thereby impart linear motion to the piston rod 63, such linear motion will in turn be transmitted from the power set 60 of the hydraulic piston and cylinder system to the slave set 46 and force the piston 48 in the latter downwardly, carrying the rack 33 to in turn effect rotative operation of the lower roll 16, driving by the gear 30, the gear 31, and thus the roll 18 likewise. Since the strip material is gripped between these two rolls, it is fed into the machine by this motion as will be apparent.

When the cam 75 reaches the point 92 between that cam and the cam element 77, the roller 82 will drop into this area, and break the circuit provided by the contacts 79 and 80. This will similarly interrupt the holding action of the solenoid 89 and permit the air to be exhausted from the air hydraulic booster 36, in turn relieving the pressure on roll 18. This relief is provided to permit the positioning of the strip momentarily in a die where pilots are provided and more than usual accuracy is required in the progressive die operation. Since this is a momentary interruption, obviously when the continued motion of the cam takes place, the contacts 79 and 80 will again be completed and the solenoid 89 actuated to direct air pressure to the air hydraulic booster 36 to again impart pressure to the roll 18 and thus continue the driving action to move the strip material into the die.

As heretofore explained, adjustament of the stroke of the power piston and cylinder set 60 will in turn cause similar adjustment of the stroke of the slave piston and cylinder set 46, and vary the amount of rotative movement imparted to the roll 16 by the rack 33.

Since the drive member 71 is of course continuously rotating with the gear 10 on the shaft 9, if it were not for the clutch 32, the rolls 16 and 18 would change rotative direction. However, since the cltuch 32 is provided, only on the downward stroke for example would driving action be imparted to the roll 16, and thus roll 18, with the upward motion of the rack 33 merely repositioning said rod and not effecting any driving action. At the same time, such upward motion is taking place, the brake illustrated in FIGURES 3 and 4 is operative to prevent any change in relative position of the rolls 16 and 18, by frictional engagement with the drum 23.

As a safety precaution and means to prevent damage to the dies if some obstruction should be encountered during feeding action by rolls 16 and 18, a press clutch control circuit is provided as now explained.

If it be assumed that the material passing through rolls 16 and 18 encounters an obstruction which in turn increases the pressure within the slave cylinder piston and cylinder unit 46 beyond a predetermined amount, the valve 52 is operated. As ilustrated in FIGURE 7, this valve includes a piston 52a therein positioned by a spring 52b, the piston connected by a piston rod 52c to a switch 93. An increase of pressure within the valve will overcome the spring action normally maintaining the switch 93 in closed condition, and thereby break the circuit provided through lines 96 and 97. The breaking of this circuit in turn causes a solenoid 98 to be de-energized and in turn interrupt the action of the air clutch through which the press is driven and instantaneously stop the crankshaft arm 8 of the said press to thereby prevent further motion of the ram 7 connected thereto.

The by-pass electrical circuit as shown in FIGURE 7 is controlled by a cam 99, also mounted on a shaft 76 for cam 75 although shown spaced therefrom in FIGURE 1 to simplify this description.

Contacts 100 and 101 are closed by contact member 102 when the lobe 99a of the cam 99 is rotated sufficiently by shaft 76, this taking place when the crankshaft arm 8 on the press has moved about degrees clockwise from the position of FIGURE 1.

Just prior to the end of this movement, the contact member 102 will have been actuated to close the circuit with contact and 101.

This occurs in advance of the abutment of the rack 33 with the stop 33w which would normally actuate the pressure switch 52 breaking the circuit and stopping the press.

The press will thereby continue its crankshaft rotation and inasmuch as the rack is moving upwardly during this time and material is not being fed by rolls 16 and 18, it will be seen that probability of damage is eliminated through the pressure switch 52 is thereby incapable of breaking the circuit as just described.

The contact member 102 will move out of actuating position when the cam 99 has again rotated far enough to permit this, and thereafter the pressure switch 52 will be the controlling factor if obstruction is encountered and pressure in the piston and cylinder unit 46 increases beyond a pre-determined point.

Such increase will be of importance usually only during the first portion of the downward stroke of the ram 7 but the cam 99 may be changed to vary this period as required It should be pointed out that in order to provide accuracy of distance of movement of the material into the press, it is desirable and necesary that the rack 33 be positively stopped at the end of its downward travel, and thus the reason for the stop 33a. Otherwise some slight overrun or underrun of material being fed in successive movements might take place. This is also the reason that the longer travel of the piston 62 in the power piston cylinder set 60 is important since it makes positively certain that the piston 48 will go through its complete cycle in downward and upward directions in order to be sure that the amount of travel of the rolls 16 and 18 is in each case precisely the same as in the preceding mstance.

Since the operation of a press of the general nature herein described is substantially continuous, it will be understood that the various phases set forth are taking place in a continuous or cyclic manner whereby identical increments of movement of material between the rolls 16 and 18 are provided.

It is pointed out that the safety arrangement just described in relation to the cam 99 is of substantial importance to prevent damage to valuable dies, and that the mechanism hereof is relatively simple although arranged in a unique manner.

The feeding device itself, or the feeder unit may clearly be located as illustrated in FIGURE 1 or at the front of the press without any difiiculty by reason of the flexible 7 connection provided by the hydraulic means for driving the slave piston and cylinder set. It is of course further clear that this feeder unit may be placed in most any position which is practical for use in relation to a press by reason of the connections, and still perform the operations intended and as explained herein.

Further, adequate pressures on the material to effect feeding are possible by the means set forth herein, with application of such pressures being arranged and timed so that they may be relieved to facilitate positioning of material within the press as by pilots located in the dies mounted therewithin, timing of the relief being contemplated as being required in accordance with the complexity of the die or rapidity with which the same is being fed.

Since there are no true mechanical connections as such, it will be seen that the speeds of operation as between the press and thus imparted to the feeding unit may be very great.

Variation of air pressure directed to cylinder 41 will correspondingly vary the pressure applied to material passing between the rolls 16 and 18.

We claim:

1. In a machine of the class described, in combination, a press, a shaft therein, material forming means in the press, mechanism to feed material to said means, including roll means, means to move said roll means into and out of feeding engagement with material supplied thereto, hydraulic instrumentalities to actuate said means, said roll means being operated in timed relation to rotation of the shaft aforesaid, and control means to precisely regulate the feeding engagement of the roll means.

'2. The combination as claimed in claim 1, wherein the control means includes means responsive to predetermined resistance to feeding movement of the material to interrupt press operation.

3. The combination as claimed in claim 2, wherein the control means also includes elements to prevent interruption of press operation when material is not being fed.

4. The combination as claimed in claim 1, wherein the means to move the roll means into and out of feeding engagement comprise hydraulic piston and cylinder units having cylinder and piston members, at opposite ends of the roll means to raise and lower certain of said means into and out of the engagement specified, said units being operable by an air hydraulic booster having piston and cylinder members therein, which booster increases pressure applied to said units in proportion to the ratio of the diameters of the piston members in each.

5. The combination as claimed in claim 1, wherein the press includes a bed and a ram operating in timed relation to the shaft, the roll means include roll members arranged to receive strip material therebetween for feeding by said members, said hydraulic instrumentalities include a first piston and cylinder set connected to rotate at least one of said roll members, a second piston and control means operate in timed relation with the shaft to regulate movement of such material in precisely said increments.

7. The combination as claimed in claim 6, wherein the control means include means responsive to predetermined resistance to the feeding movement to interrupt said ram movement.

8. The combination as claimed in claim 5, wherein the means to operate the second piston and cylinder set in timed relation to the press shaft comprise a part of the control means and include parts to adjust the stroke of the piston of said second set, adjustment of said stroke likewise adjusting the stroke of the piston of the first set accordingly, said last mentioned adjustment in turn effecting corresponding adjustment of the rotating movement of the connection of the first set with said one of said roll members. 9. The combination as claimed in claim 1,'wherein the press includes a bed, a ram movable toward said bed, the feed mechanism is supported on the press to feed material over the bed thereof, the roll means include a pair of roll members at least one of said members having a pinion thereon drivably connected to'a rack actuated by a slave piston and cylinder set of the hydraulic instrumentalities, a power piston and cylinder set of the said instrumentalities drivably connected to the slave set, and the control means comprises cam members and a rotation to linear connection of the shaft and power piston and cylinder set.

10. The combination as claimed in claim 9, wherein means are provided to move one of the roll members toward the other to effect the feeding engagement, a cam member actuates parts to effect said movement in the timed relation stated, means to restrain at least one of the roll members against rotation in one direction whilst permitting the rack to rotate said one roll member in the opposite direction, and a clutch to facilitate return of the rack to drive position.

References Cited UNITED STATES PATENTS 1,626,977 5/1927 Sibley 72405 RONALD D. GREFE, Primary Examiner

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