US1298567A - Safety device. - Google Patents

Description

C. F. ROOT.

SAFETY DEVICE.

. APPLICATION FILED ocT.5.1914.

Patented Mar. 25, 1919.

3 SHEETS-SHEET l.

C. F. ROOT.

SAFETY DEVICE.

APPLICATION FILED OCT. 5,1914

1,298,567. Patented Mm. 25,1919.

3 SHEETS-SHEET 3.

PATENT FFICE,

CHARLES E. ROOT, OF RAVENNA, OHIO, ASSIGNOR OF ONE-FOURTH T0 BYRON O. CONN, OF MANSFIELD, OHIO.

SAFETY DEVICE.

Specication of Letters Patent.

Patented Mar. 25, 1919.

To all whom z't may concern:

lie it known that I, CHARLES F. ROOT, a citizen of the United States of America, residing at Ravenna, in the county of Portage and State of Ohio, have invented certain new and useful Improvements in Safety Devices, of which the following is a specification.

This invention relates to certain new and useful improvements in safety devices foi staying machines, though equally applicable to any character or type of machine which has a reciprocating work engaging element, as for example a punching press.

The object of my invention is to provide means for automatically preventing the link that imparts movement to the reciprocating work engaging element from operating when an obstruction is inadvertently or otherwise placed between the element and the anvil and upon engagement of the element with the obstruction.

It is well known in the operation of machines that are provided with a reciprocating work engaging element which exerts a pressure upon an anvil, die or vthe like, that there is great danger of the operators fingers being inadvertently placed between the anvil or die and the reciprocating element that exerts pressure to perform the work. with the result that the fingers are crushed or injured.

rlhis is especially true when it is necessary for the operator of the machine to perform work that requires him to place his hands in close proximity to the anvil or die of the machine, and in manipulating the work his hand is liable to be engaged by the reciprocating working element at the time the latter is about to perform its work.

The primary object, therefore, of my invention is to provide means of relieving the pressure. that is exerted by the reciprocating element upon the anvil or die to perform the work when an obstruction is interposed between the anvil or die and the reciprocating element.

rlhe primary object of the invent-ion is to provide a machine of the type set forth with mechanical means embodiedin the reciprocating element, which automatically causes the element to remain inoperative,'if in its descent any obstruction, such as the hand of the operator, or one of the fingers of the hand, is met with.

Further, the invention aims to provide means which is incorpo lated in the reciprocating element so as to only render the latter opent-ire, or rigid, just prior to or at the instant of commencement of the punching, pressing, forming or stamping operation, or in other words, only at the instant that the reciprocating element is about to enter into actual or physical contact with the work.

Still further, the invention aims to provide means which is sensitive to operation by the linger or hand of the operator, should the finger or hand be in a position subject to injury by the reciprocal element, without actual injury to the finger or hand.

Furtheigthe invention aims to provide a structure which can be adjusted to operate in connection with material possessed of varying thicknesses.

The objects above described are set forth in. Letters Patent granted to ine bearing date of March 9, 1915, Patentv Number 1,131,161 and pending application bearing Serial No. 857,016, filed August 17, 1914, and the present application has the same objects in view in generalbut includes improvements in the structure described in said applications and consists in the followinonew features, to wit:

I@am actuated means to positively render the reciprocating element inoperative until it reaches a predetermined point in its working stroke and means to render said reciprocating element operative at said predetermined point or just prior to said element acting upon the work.

A .further object is to provide a safety device for connecting the reciprocating element with its actuating means that is self contained and that can be applied without making any changes or alterations in machines already in use which are provided with reciprocating working elements such as punching presses, printing presses, staying machines and the like.

Another object is to provide a safety device for actuating` the reciprocating element of the class of machines described that will be rendered inoperative, until it reaches a predetermined point in its workingv stroke, to exert a pressure upon any obstruction eX- traneous to or interposed between said reciprocating working element and the work upon which it acts although a part or parts of the mechanism be out of repair, disarranged, or broken.

A further object is to construct a: simple and effective safety device composed of minimum parts.

The essential feature of the invention comprises a link having a slot, a half link slidable in the slot, a disk having an actuating cam formed thereon, a pivoted locking bar to lock the link and half link, and means to move the bar to locking position when disengaged from the cam, the latter acting to normally hold the bar out of locking position.

A further object is to -so construct, combine and arrange the mechanism of a safety actuating means for imparting a reciprocating movement to the work engaging element of a machine, that the friction of the partsv in operation and their liability to become deranged will be reduced to a minimum so that a slight resistance or pressure exerted upon the work engaging element by a finger or other Lobstruction extraneous to the work will render the work engaging element inoperative to exert working pressure.

Another object is to provide devices which will give the very least amount of pressure on a ingeror other obstruction extraneous to the work by reducing the friction of the parts to a minimum, also reducing to a minimum the chance of said parts becoming wedged.

I attain these and other objects by the mechanism illustrated in the accompanying drawings, in which:

Figure 1 is a frontelevation of a conventional ytype of staying machine showing the invention applied thereto and also showing the finger of the operator interposed between the anvil (which has a paper box mounted thereon) and the reciprocating work engaging element;

Fig. 2 is a detail view, in rear elevation of the link. half link and locking bar, looking from the rear toward the front of the staying machine, showing the half link interlocked with the link by a pivotal locking vbar in dotted lines and unlocked therefrom in full lines.

Fig. 3 is a side view partly in section showing the l1nk,half link and locking bar,

and cam disk assembled, mounted upon `a bushing and connected to the disk and crank pin of the driving shaft.

Fig. 4 is a side elevation partly in section of Fig. 1 on a reduced scale.

F ig. 5 is a front elevation of a cam diskl showing a cam formed thereon.

Fig. 6 is a side elevation of Fig. 5.

In the drawings, the driving shaft 1 is provided with a disk 2 having a crank pin 3, the shaft being journaled in suitable bearings in the L-shaped arm 4 of a conventional type of a staying machine. Movement is imparted to the driving shaft 1 by the driving pulley 5. A head 6 reciprocates between the ways 7 and has a stud shaft `8 secured thereto. A. follower or work engagingk element 9 is securely attached to the head 6 and cooperates with the usual anvil 10 of staying machine or the like.

For the purpose of connecting the stud shaft 8 of the head to the lcrank pin 3 of the driving shaft l, by means of which reciprocating movement is imparted to the head 6, link 11, which is adapted to be interlocked with and released from a half link 12 by the pivoted locking bar 13, is provided. The link 11 is cut away or reduced on one side thereof at 14, forming a shoulder or abutment 15, which is adapted to Contact with the free lower end 16 of the locking bar and o-set portion 17 thereof.

A bearing or bushing 18 is secured to thev upper end of the half link 12 and has one end thereof slidably projecting into han oblong slot 19 which is formed in the upper part 2O of the link 11. The bushing 18 is securely fastened to the half link 12 by pin 21 and supports the link 11 and half` link 12 and in turn is loosely mounted upon the crank pin 3. The bushing 18 is also provided on one end with an annular flange 22 which fits into the counter-bored portion 23 of a disk 24.

The function of the above parts will be described more specifically hereinafter.

An aperture 25 is formed in one end of the link 11 to provide a bearing for the,

stud shaft 8 of the head 6. The locking bar 13 is pivoted to the half link 12 by the stud pin 26. A finger 27 is formed on the upper end of the locking bar.

In assembling, applying and constructing my safety device, the disk 24 is counterbored on one side, as shown at 28, to fit over the disk 2 which is carried by the driving shaft 1, the crank pin 3 passing through an aperture 29 provided in the disk. Acam 30 is provided on one side o-f the disk 24.

In connecting and applying the device to a staying machine or the like, the bushing 18 is loosely fitted in the aperture 29 in the disk 24 so as to permit the disk to rotate upon, the bushing, the annular flange 22 of` A4'the bushing seatingin the counter-bore 23 with the face 31 of the bushing flush with the face 31 of the counter-bore. The half link is then mounted upon and secured to the bushing and the projecting end 32 of the bushing passed through the slot 19 of the link 11 thereby providing means for supporting and carrying said link.

The tang 33 of the lhalf link is iitte'd to slide between the guides 34 and 35. The locking bar 13 is pivotally mounted upon the half link by inserting the stud pin 26 in a suitable aperture formed in the tang portion 33 of the half link.

The locking bar is maintained in its proper place against lateral movement by its finger 27 which projects into a space (provided by the width of the cam) between the disk 24 and the upper portion of the half link.

he operation of my device is as follows: vWhen movement is imparted to the driving shaft, the crank pin 3 imparts a combined oscillating` and reciprocating movement to the link and the half link which supports the locking bar and at the same time imparts a rotary movement to the cam disk 24 upon which is formed the cam 30 and as the disk is rotated the cam between the points 36 and 37 thereof contacts with the linger 27 of the locking bar positively forcing it to pivot upon the stud pin 26 thereby releasing the end 16 from its position in contact with the abutment 15 as ,shown in Fig. 2 in full lines, and maintaining the locking bar in said released position until the cut away portion 38 of the cam is alined with the nger 27 at which time the locking bar is permitted to pivot upon the stud pin to the locked or dotted line position shown in Fig. 2.

The spring 39 contacts with and normally exerts a pressure against the lower end of the locking bar to force the end 16 and `off-set 17 in contact with the abutment 15 and end of the half link, or in locked position. After the crank pin has traveled to a predetermined point which is preferably to within of an inch of the end of its working stroke, the end 16 of the locking bar 13 is forced by spring 39 to engage with the abutment or shoulder 15 and the olf-set 17 with the abutment 15 and the end 40 of the half link 12 (as shown in dotted lines in Figs. 2 and 3.).

Theface of the cam 30 is so arranged that when the crank pin is on its rip-stroke and has traveled to a point within 2,- of an inch of the end of its down-stroke carrying the link, half link, and locking bar, the cam will be in contact with the finger 27 forcing the end 16 of the locking bar in unlocked position as shown in full lines in Fig. 2, until the cut-away portion of the cam in its travel reaches and then vpasses the finger 27 when 'the locking bar is permitted to pivot and be forced in locked position by the spring 39.

The end 16 of the locking bar and its ofi"- set 17 engage with the half link and abutment just before the work engaging element reaches the end of its down-stroke to act upon the work and continue to be engaged therewith until the cam engages the finger 27. This operation is repeated upon each revolution of the driving shaft 1.

If an obstruction, as for instance the finger 41 of the operator, is interposed or projected between the work engaging element 9 and the anvil 10, which finger is in thickness in excess of an eighth of an inch (or any predetermined thickness) the downward stroke of the head will be arrested and the head and link will idle, the crank pin 3 completing its stroke by passing or moving, with the bushing 18, through the slot 19, since the end 16 and off-set 17 of the locking bar 13 cannot Contact with the abutment or shoulder 15, as shown in full lines in Fig. 2, owing to it-s being in a position below shoulder 15 where it cannot engage the shoulder 15 or end of the link 40 and therefore no pressure can be exerted upon the obstruction. A ball 42 is forced in contact with the side of the tang 33 of the half link by a spring 43 to provide a slight friction to yieldingly hold the half link and end link in proper relative positions for engaging the locking bar and of-set.

Attention is called to the fact that the locking bar is positively held in unlocked position by cam action until the working element reaches a predetermined point in its downward stroke, and that the cam can be readily attached to the end of the driving shaft without changing or altering the machine in any way and without the use of any appliances other than the device itself which is self-contained.

It will further be noted that the parts can not be improperly assembled as they must be mounted and held upon the bushing in operative relation to each other preparatory to applying or attaching them to a staying machine o1' the like.

Attention is further called to the fact that the off-set 17 is wedged between the end 40 of the half link and the abutment 15 when pressure is exerted upon the element and at the same time the end 16 of the half link is in contact with the abutment 15 to thus provide a firm footing or point of bearing of locking bar 13 on shoulder 15.

That I claim is:--

1. In a safety device, in combination with a reciprocating work engaging element, a driving means, means to connect the driving means and work engaging element, a disk mounted on the driving means having a cam formed thereon `to maintain said connecting means inoperative, means on said cam to' alloW said connecting means to be rendered operative at a predetermined point in its Working stroke When the path of the ele- ,ment to the Work yis unobstructed, and means to actuate the connecting means to render same operative.

,2. In a safety device, in combination With a A,reciprocating Work engaging element, and an anvil, a driving mechanism, means yto connect said Work Vengaging elementto said driving mechanism, a removable `disk connected tothe driving means .and having a cam to permit the vconnecting means-to be rendered operative at a predetermined point and means-to actuate the connecting Ameans to render same operative.

3. .In a ysafety device, `having a `Work vengaging element and means yfor reciprocating same, a removable disk attached to said means vfor reciprocating the Work engaging element and having va cam, and means controlled by the cam Whereby the means for reciprocating the Work engaging element is lrendered inoperative until it reaches a pre determined point in its Working stroke, and is rendered operative after it vreaches said point. and 'When the path of the elementito the Work is free.

4;. In a machine having a Work engaging element and anvil, lmeans for reciprocating said element including a link and half link relatively movable, a lockinobar for locking and unlocking said link andh half lin-k, adisk Vhaving a cam formed thereon attachable to the means for reciprocating the Work engaging element for actuating the locking bar 'to unlock the link and half link and for allowing locking of the link and half link, and meansto actuate the bar into interlocking position When .the path ofthe element to the Work is free.

5. In a machine having a reciprocating Work engaging element and an anvil, a driving means, means comprising a full link and half link relatively movable fto connect the drivingmeans and reciprocating Work engaging element, a locking .bar adapted to be locked With and unlocked fromsaid link and half link, means to move said locking bar half link relatively movable to connect the driving .means and reciprocating Work engaging element, a locking bar adapted to be locked With and unlocked from said link and half link, adisk having a cam .formed thereon attached to said driving means to move the locking ,barffrom alocking positiommeans to actuate vthe locking lbar to :move same "to locking positionWhen the vpath of Atheelement .to the Work is free.

l7. In combination yWith ananvil, a Work engaging element,;and a driving means including an ordinary disk andveccentric pin,

means to connect said Work engaging .element and driving means, meansattachable to both,

8. ,In a safety device for a machine .having a Work 4engaging element and an anvil, means to reciprocateJ the Work engaging element to exert pressure upon the anvil includinganordinary disk andeccentric pin and means attachableto .both the disk and pin Without their modification to thereby iixedly support and position said means to ,render said reciprocating means linoperative and to prevent same from exerting pressure upon the Work When the Work engagingelement is subjected to pressure by van 4obstruction ex traneous to the Work and which is in the path offtravel of the Work engaging element.

9, In a safety device .for a .machine equipped With a reciprocating Work engaging element and an anvil,driving means for said element, including an ordinary disk and eccentric pin, means to yconnect said driving meansand Work engaging element, 'means attachable to both said disk ,and pin Without their modification, to thereby lfixedly support and .position said means to actuate said connecting means to eXert pressure upon `the anvil and means to render saidv connecting means inoperative so as to prevent same from exerting pressure When the Work-engaging element is vsubjected to pressure by an'obstruction in its `path 'of travel, thicker than the Work.

10. In a safety attachment .for a machine equipped With a reciprocating Work engaging element and an anvil, a ldriving `means including an ordinary disk and eccentric pin, means to connect .said Work engaging element and drivingl means, means attachable to said disk and pin Without `their modification and sof .ioo

removable from the driving means Whereby a `reciprocatory Work-engaging element and an anvil, of driving mechanism, yieldable means connecting the Work-engaging element and the driving mechanism, and means removably mounted on the driving mechanism for controlling the operation of the yieldable connecting means.

12. In a safety device, in combination with a reciprocatory Work-engaging element and an anvil, of driving mechanism, yieldable 10 means connecting the Work-engaging element In testimony whereof I aiix my signature 15 in presence of two Witnesses.

CHARLES F. ROOT. Witnesses:

JOHN H. Cose, PEARL M. YUNOHER.

Copies of this patent may be obtained for ve cents each, by addressing the Commissioner of Patents, Washington, I). C.

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