US2038795A - Releasing means for jammed presses - Google Patents

Description

April 28, 1936. w. KLOCKE RELEASING MEANS FOR JAMMED PRESSES ma ma 2 Sheets-Sheet 1 Filed Oct. 9, 1934 INV %/AL/HM K 0 BY P 1936. W. KLOCKE 2,938,795

RELEASING MEANS FOR JAMMED PRESSES Filed Oct. 9, l9 34 2 Sheets-Sheet 2 44 W Q 24 ii- INVEN W/LL/fi/M KLO Patented Apr.

UNITED STAT force applied through the tool-carrying slide (or This invention relates to presses, and provides improvements therein. i

In the operation of crank-actuated presses, the

,5 'slides) ordinarily rises to a very great amount at or about the end of the :great strains or tension in working stroke, which causes the press-frame, and

sometimes, when for example a foreignpiece of J metal is accidentally piece to be shaped i the piece does not left between the dies, or the s too thick, or the metal in flow as expected, the press- .parts seize or become comes jammed; and it bound and the press beis usually a difficult matter to free the press. In many such cases it is necessary to destroy expensive thousands of dollars,

dies which often cost before the press can be freed.

The difiicultyof freeing a jammed press having a frame of plate-steel (such 'as has come into use of late for large an d powerful presses) is particularly great. With a press having a frame in which the tension is can sometimes be freed byapplying heat to borne by tie-rods, the press the tie-rods so as to lengthen them by expansion, but

a'jammed press having a plate-frame cannot be effectively handled in a similar manner.

The present invention provides a means for backing-off the toolin the jammed position carrying parts (as the slide) of the parts, so that a jammed press may be readily and quickly freed without injury to the press or the press readily and q' tion.

press parts, and okly'restored to opera- Embodiments of the invention are illustrated in the accompanying drawings, wherein:

Fig. l is a view showing a front elevation of a simple type of press, a plate-steel frame being illustrated; and

Fig. 2 is a view showing a side elevation thereof.

Fig. 3 is a view partly in side partly in section, of

elevation, and the slide, and showing the backing-off means incorporated therein.

Fig. 4 is a View of a section on Fig. 3.

the line IV-IV,

Fig. 5 shows a modification in which the invention is applied to a single crank and slide connection, the view being a transverse vertical sectional view through the crank and slide.

Referring to said drawings, numeral I e designates a press-frame, I2 and I4 tool-carrying parts,

and ['6 means for moving said parts l2 and M "to and from one another.

The tool-carrying parts, l2 and H1, in the type i and example of press illustrated, comprise a bed -20 and a-reciprocato n su tabl guides ry slide 22 adapted to move .24. .1 e, ra e- Too s other. connecting-rods (30, 30) is illustrated in Figs;

jning from bed to s Tiwrlazu'r OFFICE punches and dies of various kinds, (not shown) for metal-forming, are mounted on the bed 20 and slide 22.

The means IS, in the type and example of press illustrated, comprise a crank-shaft 3B and a rod 32 connecting the crank and slide 22.

thrust derived from the having a narrow span, the

In a press crank-shaft ordinarily is applied to the slide through a single connecting rod, while in presses having Wide spans the thrust is ordinarily applied to the slide through two (or the side-thrust of one rod is An example. of a pr even more) connecting-rods moving in unison'and arranged so that counteracted by aness having a pair of 1-4 inclusive, and an example of a press having a single connecting-rod is illustrated in Fig. 5. The

crank-shaft (or shafts) may able means. As shownin be rotated by suit- Figs. 1-4 a' pair of crank-shafts 30, 30' may be provided: running across the frame from front to back. Gears 34,

34, one on each crank-shaft, may be provided,

and these driven from a com pinions 38, 39, the pinions be the gears 34,

mon gear 36 through ing arranged to drive 34 and the crankshafts 30, 30' in unison in opposite directions, so that the sidethrusts of the rods 32, 32' are in opposite directions and counteracted. This is an advantageous arrangement for heavy-duty presses, the sideframes being thereby largely relieved of strains which could produce deflection.

The press-frame frames Ill lll a crown 10 locked or welded together,

It! illustrated comprises sideand a bed lll these parts being formed of heavy steel-plate, interand constituting a frame which is strong and with only a slight amount of yield, usually less than in press-frames in which the tension is sustained by tie-rods runcrown. The force applied between the bed and crown and sustained by the side-frames, in some of the larger presses which have been built, is calculated as being 3000 tons.

is in its lower position and The maximum force is applied when the slide 22 at some point in the arc of movement of the crank lying within 15' degrees or so of its dead center position. During the forming operation which takes place between the tools carried by the slide and bed, thepressframe, including the side frames, the tie-rods, if used, and the driving parts, are stressed enorand the force of resistance caused by said stresses at the peak of the load is often of a value comparable with the maximum force which .can be applied for driving. mishap, such as an excess 0 When through some i metal being placed F heating isjnot adaptable for entireconnectionwould have to be heated, which between the crown necting-red, a separate between the press-tools, or a Workman inadvertently leaving a hand-tool on the bed of the press,

or on a die, etc., the resistance may rise to an amount exceeding the maximum force which can,

be applied for drivin the stressesrise to enormous values, and :the parts seize or bind the press jams, and the press cannot be freed by force applied through the driving parts. Moreover the stresses are so greatthat the threaded parts such'as'employed in presses, as for example, the nuts on tie-rods (in that type of press), and adjustable connections in the connectingi rods, cannot be moved. The methods heretofore employed for freeing a jammed press are slow, precarious and often costly; With presses constructed withtie-rods, the usual practice in freeing a pressis to heat the tie-rods to produce an the stresses and'the resistance which the driving parts have to overcome to back-ofi the slide. This is slow, and apt to damagethetie-rods, and is sometimes not effective, In presses'having frames of the plate-steel type, the method of in turn'wouldtwist the frame section out of shape,

and which on cooling would not come back to its original position. 'Whe're heating is ineffecare so jammed that the total-carrying parts cannotbe moved apart by forc driving means, r

The means 44 is preferably a wedge 46 suitably placed between the frame and a tool carrying part, the most advantageous location being betweenthe'slide (22) and the'crank-shaftflfl) applied to the pressat the foot of a connecting-rod (325. With that arrangement a block 48 is provided in a seat 50 in the slide (22), the wedge 46 being interpo'sed between the block and the bottom of the seat, the said seat and the abutments 58 hereinafter referred to constituting means on the slide providing bearings, spaced'in line with the direction of reciprocation of the slide for loosely receiving saidblock 48;

46 and the bottom of the block 48'are formed-at 'such an angle that the The face of the wedge force component at right angl'es'to the thru'stof the connecting-rod on the working stroke (or the direction of the stress W and bed 20) is great enough, when free to act or whenauginented with an extraneous force also at right angles to said thrust or direction of stressforthe wedge to be readily moved or be displaceable, even under the enormous stresses existing in a jammedpress, tobalck olf the slide (22) from the opposite tool-carrying part (bed 20) and free the press. A bearing 52 is preferably provided in the block for the end 54 of the connecting-rod, and a pin 56 provided for maintaining the con nection between the end of the conne'eting-rod and the block. When there is more than one conerably provided for" each connecting-rod.

Suitable" means are provided for fastening the block 48 in its seat inthe slide 22. For such p pose theslide may be provided with a flange or expansion for easing" the reason that the shafts 30,. 3|; and connecting 7 move the tool-carrying parts apart, whereupon .abutments) dition.

7 than those herein backing-01f means is pref- Vabutment e58 constituting which the block (or a shoulder therein) is pressed by the wedge 46. and threaded-rod is preferably provided for forcing the wedge 46 iniunder the block 48 to press and hold the block against the abutment 58, and thereby provide a fast connection between the connecting-rod 32 and theslide 22. In a press having two connecting-rods, as shown in Fig.1,

the Wedges are preferably oppositely arranged and forced apart in engaging threaded'rods To free a press which is jammed and provided 5 w1th releasing means according to my invention; the wedge-48 is displaced in the direction of the force component tending to force it from beneath the block, sueh extraneous force as maybe necessary ,to efiect its movement being supplied 'by striking the end of rod 5| (after loosening the nut 50) ,Fig. 5;or by turning the turn-buckle 62, Figs. 1 and 3, whereupon the tool-carrying parts a bearing against Suitable means, as a nut 50" unison by a turn-buckle 62 V 63, 64 thereon, to force the blocks 48 againstthe abutments 58.

(slide 22 and bed move apart oribacksoff,

reducing the stresses in the press-frame to a degree where the ,force applicable through the driving means '(gears'36; 38, 39, 34, 34", crankrods 32, 32) can the press is freed, the freeing operation, being readily and quickly'performed, and Without injury to the press or press-parts. After the press is freed,;it may befreadily and'quickly restored to operatingcondition by forcing the wedge'46 c blocks) is pressed against the abutment 58 (or Unless the setting of the dies has (or Wedges) inwardly so that the block 48- (or been, disturbed, it'is not even necessary to reset these to have the press again in operating con- Theinvention'may receive other embodiments scribed. a

What is claimed is: 7 f V 1; In a press, the combination of tool-carrying parts one of which is a reciprocatory slide, a crank shaft, a pitman-rod connected to said slide and crank-shaft, a frame forsustaining'the respecifically illustrated and deactions and strains produced in said tool-carrying parts incident to a forming operation, and means for backing-off said tool-carrying parts from one another'when the press-partsare so jammed that said tool carrying parts cannot be moved apart by force applied through said crank-shaft, said means comprisin a bearing- "block at the slide-end of said pitman-rod, means on said slide providing bearings, spacedin line with the direction of reciprocati'onof said slide, for loosely receiving said bearing-block, a wedge under said bearing block in contact with one of said bearings on theslide; adapted to be driven to force said block rigidly against the other of said bearings on the slide; andfurther adapted to be removed in case therpress jams, and means for rigidly maintaining said wedge against displacement.

2;"In' a press, the combination of tool-carrying parts, one of which is a 'reciprocatory' slide, a

crank shaft, a pairof pitman-rods connected to said slide and crank-shaft, a frame for sustaining the reactions and strains produced in said tool-carrying parts incident to a forming operation, and means for backing-elf saidtool-carrying parts from one another when the press-parts are so jammed that said tool-carrying parts cannot be moved apart by force applied through said crank-shaft, said means comprising, a bearingblock at the slide-end of each of said pitmanrods, means on said slide providing bearings, spaced in line with the direction of reciprocation of said slide, for loosely receiving each of said bearing blocks, a wedge under each of said bearing blocks each in contact with one of said bearings on the slide respectively, and adapted to be driven to force its respective block rigidly against the other of said hearings on the slide, and. further adapted to be removed in case the press jams, said wedges being oppositely arranged, and means for forcing said wedges to move in unison, said means operating to rigidly maintain said wedges against displacement.

3. A combination according to claim 1, further comprising means independent of said wedge for adjusting the effective-length of said pitman-rod to provide for the adjustments requisite for obtaining proper clearance in setting the tools preparatory to use of the press.

KLOCKE.

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