US385099A - Printing-machine - Google Patents

Description

2 Sheets-Sheet 1.

PRINTING MACHINE.

Patented June 26, 1888.

0. B. GOTTRELL.

@To Model.)v

(No Model.) 2 sheets-sheet 2. C. B. GOTTRELL.

PRINTING MACHINE.

No. 385,099. ,l q Patented June'f 26, 1888..

ljinl Nrnn STATES ATENT trice,

CALVERT B. COTTRELL, OF STONINGTON, COI\U\TECTICVI`.`

`ranvrlrve-ivlAeHltu-L SPECIFICATION forming part o1 Letters Patent No. 385,099, dated June 26,1888.

Application tiled October 29, 1887. Serial No. 253,687. (No model.)

To aZZ whom, it may concern:

Be it known that I, Gnnvnn'r B. CoCr'rRELL, of Stonington, in the county of New London and State of Connecticut, have invented a new and useful Improvement in PrintingMachines, of which the following is a specification.

My invention relates to printing-machines which comprise an impressioncylinder and a reciprocating bed, in which the bed is operated by a mangle motion or pinion and rack gearing, giving it a definite range of reciprocation. In such machines an air spring or cushion is commonly employed at each end of the machine for arresting the movement of the bed as'it approaches at full speed the end of its movement, and it is obvious that if the air spring or cushion does not arrest the movement of the bed at the desired and proper point the momentum ofthe bed will produce a severe strain and shock upon the mangle or other gearing, inasmuch as the rack and the lbed are usually rigidly connected.

My invention is applicable with great advantage to all machines of this character in which the speed varies, and particularly machines employed for lithographie purposes, in

which there is a great difference in weight between different stones which are used upon the bed, as it is obvious that with a very heavy stone or at high speed the bed would have a greater tendency to overrun than it would with a lighter stone or less speed, and consequently would require the adjustment of the air spring or cushion to arrest `it without subjecting the rack and pinion to great shock and strain.

An important object of my present inven` tion is to provide means whereby the rack and bed are so connected that while they are rigid during the main portion of the reciprocating movement they may be at each end of the stroke of the bed permitted to move sli ght ly, one relatively to the other, so that in case of a very heavy stone being placed upon the bed, or the bed run at high speed, the bed shall be permitted to move slightly ahead of -the rack at the end of its stroke and until arrested by the air spring orcushion; and a further important object of the invention is to provide means whereby such slight sliding movement of the bed ahead of the rack in case of a very heavy stone or high speed, or both, or

sliding movement of the rack ahead of the bed, as soon as the latter strikes the air-spring, in case of a very light stone or slow speed, or both, shall act through suitable mechanism to automatically vary or regulate the resistance offered by the air spring or cushion,or any other spring or cushion which may be employed, to the movement of the bed.

In carrying out my invention Iconnect the rack with a hangerfrom the bed, so that a slight sliding movement of one relatively to the other may be permitted, and this result may be accomplished by connecting the bed and hanger by swinging links; and for locking the rack relatively t0 the hanger and bed, so as to prevent any sliding movement of one relatively to the other during the principal` part of the movement ofthe bed, I employ toggle-levers having one pivot-al point iixed upon the rack and having its other pivotal points vupon blocks or slides which have a limited sliding movement in openings in the hanger. When these toggle-levers are straightened or brought into line, the blocks which slide in the hanger abut againstthe ends of the slots wherein they move, and the rack is then rigidly connected with the hanger, so that no sliding movement of one relatively to the other is permitted.

At one or each end of the machine I employ a cam with which atruck-rollerupon the toggle-levers comes into engagement at the `ends ofthe beds movement, and which acts to de fleet or break up the toggle-levers., so as to leave the rack connected with the hanger only by its swinging links or other means which provide for the sliding movement ot the rack and bed, one relatively to the other.. In connection with each air-spring Iemployamechanism whereby it may be adjusted to vary the resistance offered to the movement of the bed 5 and this mechanism in the present example of my invention consists of a ratchet and a lever carrying pawls geared with the screw, upon which is mounted a head fitting the cup-shaped plunger, as is shown in the application of Charles P. Cottrell, tiled October 26, 1887, and the serial number of which is 258,425.

The pawl-carrying levers of the mechanism at opposite ends of the machine are connected by a rod, and I provide tappets upon the bed or upon the part carried thereby, which will IOO be moved into operative position by the shifting of the rack and bed, one relatively to the other, and which act upon collars on the aforesaid rod, so as to operate automatically the mechanism whereby the air-springs Yare adj usted to vary or regulate the resistance opposed by them to the movement of the bed. These tappets may consist of arms which are connected with the links connecting the bed hanger and rack, so that they are thrown into operative position bythe movement of the bed and rack, one relatively to the other. I also provide mechanism operated by'a handlever, whereby the cam .at one ory each end of the machine which acts to break or deflect the toggle-levers on the bedhanger may be moved out of operative position after the air-spring has been adjusted to offer the proper amount of resistance to the movement of the bed.

In the accompanying drawings, Figure 1 represents a longitudinal section of such parts of a printing-machine as are necessary to illus trate my invention, and Fig. 2 is an end view including a partial section of the bed-rack and its hanger upon about the plane indicated by the dotted line x x, Fig. 1. Fig. 3 is a side view of the mechanism which vmay be operated automatically or by hand to vary the air spring or cushion, such view being similar to the representation of the mechanism in Fig.

1, but `upon a larger scale; and Fig. 4 is an.

edge View or illustration of such mechanism similar to Fig. 2, but on a larger scale. 5 is a modification of a detail, hereinafter referred to. y

Similar letters of reference designate corresponding parts in all the figures.

A designates the impressionfcylinder, and

VvB the bed, which may be connected with the impression-cylinder by any'of the ordinary systems of gearing, so as to cause them to operat'e in unison, and which is supported by shoesor bearers b upon' the main frame C of the machine. rIhe bed has depending from it the usual hanger, B,witl1 which is connected, and which serves to carry,the rack D, and this -rack is here shown as a mangle-rack, and is operated by'a pinion, d, upon a jointed shaft,

D', in the usual way, as shown in Fig. 2.

For arresting the movement of the bed at theend of its reciprocating stroke in either direction, Iemploysprings or spring-cushions, here represented as composed each of a cylinder, E, and'a cup shaped plunger, E', which is provided with a suitable packing, e, and which is arranged with its open end presented in an opposite direction tothe open end of the cylyinder. Within the cup-shaped plunger E is a sliding head, Ewhich, .by means of ascrew, E3, may be shifted lengthwise of the plunger E', so as to varythe amount of air trapped between the plunger and the cylinder at the time the cylinder-strikes the plunger and to vary thespace wherein the air is compressed. As here represented, the screw E3 is fitted, as in` 'a nutto the head E2, and by turning the screw inrone or other direction the head will be moved Fig.

lengthwise within the eupshaped plunger E',

as is described in the aforesaid application of Charles P. Cottrell. The plunger E is secured through a bracket, E, to a portion of the framing C; and I will now describe, with particular reference to Figs. 3 and 4, a mechanism, which is also shown in Figs. 1 and 2, whereby the screw E3 may be turned and the head E2 shifted.

The screw E, which is at each end of the machine, has a cross-shaft, E5, connected with it by bevel gear-wheels e', and upon this shalt is secured a toothed ratchetwheel, e?. Upon the shaft is loosely pivoted a lever or arm, e3, carrying pawls e4, presented in opposite directions to the teeth of the wheel el; and e5 represents an arc-shaped guard, which covers the upper portion of the wheel e and serves as a rest for the pawls c4 to keep them out of engagement with the wheel e2 when the lever e3 is adjusted to mid-position, as shown in Figs. 1 and 3. hand or automatically in either direction, the pawl which passes off the guard or shield e, will drop into engagement with the wheel e2 and will impart a turning movement thereto. As before slated, such a mechanism is arranged at each end of the machine for varyingV the air spring or cushion ateach end, and the two mechanisms are shown as connected by a sliding rod, E, which is fitted to suitable guides, e, and is connected by links e7 with the lower ends of the lever e, I have represented springs es as applied between the guides or bearings e for the rod EG and collars e9 on said rod, and these springs es return the rod E and the pawl-levers e3 to mid-position after each operation, so that the pawls will rest upon the shield e of each mechanism.

VThe mangle or other rack D, during the principal portion of the reciprocating move- If, however, the lever es is swungby ICC ment of the bed B, should be rigid upon the connected by swinging links d di. iThe link d forms a part of anarm or lever, D2, which is fulcrumed at di to the rack D and is connected at the pointol4 to a bracket or arm projecting downward from the hanger B. The link d2 forms a part of an arm or lever, D3, which is fulcrumed at the point d3 to an arm or projection on the rack D and is connected at the pointd* to the hanger B.

From the above description it`will be understood that in case the bed and hanger B B slide toward the right relatively to the rack D as they complete their reciprocation toward the right suchv movement will throw the upper end of the arm D3 toward the right hand of IIO the'drawings, Fig 1, and will throw the upper l the cylinder and plunger.

end of the Fig. I. l

I will now describe the means whereby the rack and bed are locked relatively to each other, so that there can be no sliding movement of one relatively to the other during the principal part of the reciprocating movement.

F F designate three levers or bars, which are connected so as to form toggle-levers. The bar F'is pivoted at the pointf to axed pin in the rack D; but the bars F are pivotally connected at the points f to blocks f 2, which have a limited sliding movement in openingsf in the hanger B', and which are not connected with the rack. The bars F F are pivotally connected together at the points f, and it will be obvious that when these bars are brought into a straight line the blocks f 2 will be moved in opposite directions, so as to abut against the outer ends of the openingsf, and thus form a brace of fixed length to hold the rack and the hanger B against sliding movement, one relatively to the other. When the toggle-1evers are broken or deflected from a straight line and to the position shown in Fig. 1, such limited movement is permitted to the extent of the distance between the blocksf2 and the outer ends of the openingsf3 in the hanger B. Upon the bar F of the toggle-levers is a truck roll or pin,j`5, which, as the bed is reciprocated, may be alternately engaged with curved grooves or waysf6 in cams or cam-blocks F2, iitted to slide in suitable guides or slideways, fl, at opposite ends of the machine. When the cams F2 are slid toward each other to the position shown in Fig. l, and supposing that the toggle-levers F F are straightened and the bed is moved toward the right hand of Fig. l, the truck-rollf5 will enter the groovef in the right-hand cam F2, and will thus break down the levers or deiiect them to the position shown in Fig. 1, which is before the pinion d rounds the shoe at the end of the rack. Ve will suppose that a very `heavy stone has been put upon the bed B or that the speed is inv "creased, or both, and that the bed has just arm-D2 toward the left'hand of completed its reciprocating movement to-A ward the right hand of Fig. l. The togglelevers F Fhave been deflected by the cam F2, thereby leaving the bed free to slide slightly relatively to the rack D, e nd when the rack has bythe pinion d been brought to the right hand of its stroke the momentum of the bed causes it to slide relatively to the rack towardthe right hand of Fig. l. This overrun of the movement of the bed acting upon the lever or arm D3 throws it toward the right and against the right-hand collar, e, of the rod E, and by moving said rod toward the right hand the pawl-levcr e" at the right-hand end ofthe machine is operated so as to shift the head E2 in the air-spring toward the open end of the eupshaped plunger E', thereby tending to decrease the volume of air which is trapped in the cylinder E at the moment that it strikes the plun-A ger E' and decreasing the air-space between Through the rod E6 alike operation of the air-spring mechanism at the left hand of the machine is also produced, and as the bed commences its reciprocation toward the lefthand the cam F2, through the truck-rollf5, serves to straighten the toggle-levers F F and bring them into a locking position. Vhere the stone upon the bed is extraordinarily heavy or the speed high, this automatic adjustment of the air-spring is performed each time that the bed comes to the right-hand end of its movement until the adj usting mechanism is no longer affected, and when the attendant sees that this is the case he operates a hand-lever, G, which is fulcrumed at g, to move the cams F2 away from each other and out of operative position. I have shown each cam F2 as moved by togglelevers f/ g2, having a movablecenter, g3, and fixed centers g4 g5. I have shown the pairs of toggles as connected by a rod, g, and with one pair the hand-lever Ur is connected by a rod, gl. Therefore it will be understood that by moving the hand-lever toward the left of Fig. I both pairs of toggles will be broken up or deiiected and the cams F2 moved in opposite directions to such position that they will not operate the truck-roll f5.

Having thus described how the benl B will, in case of a very heavy stone being placed thereon, or high speed, effect the automatic adjustment of the air-springs, so as to increase the resistance which they offer to the movement of the bed, I will now describe how, in case of a very light stone being put upon the bed, or a slow speed, or both. and in case the air-springs would serve to check the movement of the bed before the rack has quite completed its movement, the air-springs will be automatically adjusted so as to decrease the resistance which they offer to the movement of the bed. It is, of course, obvious that the air-springs should not be of a strength sufticient to stop the bed before the rack has completed its movement, because in that case` the labor of overcoming such resistance would have to be performed by the mangle-gearing until the rack had fully completed its movement.

Suppose that the bed is moving toward the left hand of Fig. l, and that the air-spring at the left hand ofthe machine has checked the bed before the rack D has quite completed its movement. Obviously the rack will move ahead of the bed and will throw the upper end of the arm D2 toward the left hand of Fig. 1, and `such arm, by acting upon the collar e, will, move the pawl lever ci and will shift the head E2 in the left-hand air-spring toward the closed end ofthe plunger It', thereby increasing the volume of air which is entrapped in the cylinder E when it strikes the plunger and increasing the space between the cylinder and plunger. This action is repeated at each lefthand movement of the bed until the air-spring adjusting mechanism is no longer operated, andthen the cams F2 are moved ont of opera- After any change of stones on tive position.

lOO

the bed or change of speed the cams F2 are moved into operative position, when the machine is started, and then the machine will automatically adjust its air-springs to exactly suit the weight ofthe bed and speed, and the cams F2 are then moved away from each other and out of operative position.

From the foregoing description it will be obvious. that the lever or arm D3, which isoperated when the bed is run at a high speed, or when a very heavy stone is in place, to adjust the air-spring at the right-hand end of the machine, may serve simply as an indicator to the attendant, and when he sees by the movement of said arm D3 that the bed is running ahead of the rack at the end of the movement ofthe bed toward the right hand he can operate by hand the spring-adjusting mechanism, which is at that end of the press, and through the rod E6 he will operate the spring, which is at the opposite end of the press. It is also obvious that a movement of the bed and the rack, one relatively to the other, may be utilized simply for shifting the air-springs in case of a very heavy stone or high speed, or both, and that the attendant may, through the springadjusting mechanism, adjust such springs by hand to suit the slower speeds and lighter stones. It is also obvious that the rod gi, connecting the toggle-levers which operate the two sliding cams F2, may be dispensed with and a hand-lever and rod, G gi, similar to those at the right-hand end ofthe machine, may be applied to the cam F2, which is at the lefthand end of the machine.

I have aboveidescribed the toggle-levers F F as having a fixed pivotal point, f, on the rack D and other pivotal points, f', on blocks.

f2, which slide in openings in the hanger; but it is obvious that exactly the same result would be secured by having the Iixed pivotal point f upon the hanger and the blocksfz, on which are the other pivotal points, f, sliding in the rack. This modification, which is the full equivalent of the construction above described, is illustrated in Fig. 5, which is a horizontal section through the rack and hanger. In that figure it will be seen that the fixed pivotal pontf is on the hanger and the bloeksfz, on which are the other pivotal points, f', slide in openings f3 in the rack.

From the former description it will be ob- Vious that not only do Iprovide for adjusting the resistance offered by the air-springs to the weight of the stone upon the bed, butwhat is of still more importance, I provide for adjusting such resistance to suit the speed at which the bed is operated, for, as is well known, the 'momentum ot' a moving body increases as the square of the speed.

What I claim as my invention, and desire to secure by Letters Patent, is-

l. The combination, with the bed of a cylinder'printing-machine and a rack-and-pinion gearing for operating the bed, the rack of the gearing being hung from the bed to provide for a slight lengthwise movement of one relative to the other, of springs or cushions to arrest the movement of the bed without shock, mechanism, substantially as described, for regulating or varying the resistance which the springs or cushions oppose to the movement of the bed, and tappets which are'carried by the bed and are shifted by the movement of the bed and rack, one relatively to the other, to operate through the said mechanism for varying the resistance offered by the springs or cushions, substantially as herein set forth;

2. The combination, with thebed of a printing-machine and a rack and-pinion gearing for reciprocating it, the rack of said gearing sliding in the hanger on the bed and connected with said hanger by swinging links to provide for a slight sliding movement of the rack and bed, one relatively to the other, of toggle-levers having a pivotal point fixed on the rack and other pivotal points upon blocks having a limited sliding movement in the hanger,

whereby when the toggle-levers are straightened the bed and rack are locked against sliding movement, one relatively to the other, a cam at one or each end of the machine with which a truck-roll on the toggle-levers engages to break up or deflect the toggle-levers, air springs or cushions for arresting the movement of the bed, and mechanism,substantially as described, for varying the resistance offered by the air springs or cushions, substantially as set forth.

3. rIhe eombination,with the bed of a print` ing-machine and a rack-and-pinion gearing for reciprocating it, the rackof the gearing sliding in the hanger on the bed and connected therewith to have a slight sliding movement between the rack and bed, one relatively to the other, of toggle-levers having a pivotal point fixed on the rack and other pivotal points on blocks having a limited sliding movement in the hanger, whereby when the levers are straightened the bed and rack are locked against sliding movement, one relatively to ICO the other, a sliding cam at one or each end of the machine with which a truck-roll on the toggle-levers engages to break up or deflect the toggle-levers, a hand-lever and connections for sliding saidcam into and out of operative position, air springs or cushions for arresting the movement ofthe bed, and meehanism,substan tially as described, whereby the resistance offered by the air springs or cushions may be varied, substantially as herein set forth.

4. rlhe combinatiomwiththe bed of a printing-machine, air springs or cushions for arresting its movement in opposite directions, and mechanism, substantially as described, for varying the resistance offered by the air springs or cushions, the mechanism at opposite ends of the machine being connected by a rod, as EG, of the'raek-and-pinion gearing for operating the bed, including a rack having a slight sliding movement between it and the bedhanger,togglelevers,as described, whereby the rack and bed may be ioeked to prevent such and cams atopposite ends of' the machine for 'sliding` movement, arms D2 D3,Which are eonbreaking up or deeeting the toggle-levers, necked with the bed-hanger and rack so as to substantially as herein seb forth. y

be operated one by che bed running ahead of CALVERT B. COT'IRELL. y 5 the rack and the other by the `rack running Witnesses: y v y ahead of the bed, and which operate on the G. HALL,

rod E to vary both air springs or cushions, FREDK. HAYNES.

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