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Publication numberUS2821907 A
Publication typeGrant
Publication dateFeb 4, 1958
Filing dateJan 10, 1955
Priority dateJan 10, 1955
Publication numberUS 2821907 A, US 2821907A, US-A-2821907, US2821907 A, US2821907A
InventorsStone Morris D
Original AssigneeUnited Eng Foundry Co
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Indicating device
US 2821907 A
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Description  (OCR text may contain errors)

Feb. 4, 1958 M. D. STONE INDICATING DEVICE Filed Jan. 10, 1955 2 Sheets-Sheet 1 MORRIS D. STONE Hm HTToRNEY Feb. 4, 1958 M. D. STONE INDICATING DEVICE 2 Sheets-Sheet 2 Filed Jan. l0, 1955 lm. M, W, l. U H.

. INVENTOR. on la D ToA/E BY Y Afm HTTORNEY Unitedv States Patent O 2,321,901 I'NDICATING DEVICE" Morris D. Stone, Pittsburgh, Pa., assignor to United Engineering and Foundry Company, Pittsburgh, Pa., a corporation ofiPennsylvania i v Application January 10, V1955, :Serial No. 480,852 1s Claims. (Cl. 10o-99) Thisdnvention relates toI an indicating device` and ,in particular toa' device adapted to. be'used in combination with ay press,- *for-` example, having a stationary and, a movableqplaten, and by which device an eccentric loading condition imposedupon thepress movable platen may be freadilyydetermined.

In theoperation of largehydraulic forging presses, there are mnyinstances in whichthe loadimposed upon the pressplaten is ,eccentric to thecenter line ofthe press so that considerable stress is placed upon many of the press elements and, unless such condition is corrected for either by ,repositioning the workpiece and dies relative to the press platens-,fwhichwould be the most desirable thing todo `in-lcase` repeated forging operations of the same identicaLnatureare to `be vcarried out,or by, imposing a righting moment on the eccentrically loaded platen of the press inforder "to overcome the v.effect of the eccentric loading,-possible permanent damage may result to the press. Y

In order that'the existence of an-eccentric loading condition which maybe imposed upon the movable platen will he readily determinable so that` the operator may take the corrective. measures heretofore mentioned, or even shut down the press-if such is necessary to prevent damage thereto, the .invention herein disclosed-contemplates generally an indicatingdevice having a beam producing source actuated by-pressures incident to theapplication of an eccentricfloading condition imposed upon the press platen and a targetIup-on which the beam impinges so that by the position atwhichthe beam strikes the targetthe existence ot` such eccentric loading condition will be evidentto the operator. t

In a specific embodiment of the invention as herein disclosed therefis provided an indicator which includes a movable platen simulating the movable platen of an hydraulic` press and to which there are transmitted forces incident to eccentricpressures applied to the platen of the-,press land tending to cause tilting thereof with respect Yto, agiven base,` the indicator platen being provided with a light lieamsou'rce and so arranged toproject the beam vonto a ground glass screen having areas or kerns marked thereonwhich define thepermissible and critical eccentric loading limits to whichA the movable platen of the press may. be'subjected so thatl by the position at..which the beam strikes such vareas there will be anindication of the extent of the pressV platen eccentric loading condition. l

,It is` accordingly an object of this invention to provide anindicating device which includes ya beam source and eccentric moment responsive means connected thereto and ,tof the ymovable ,platen of a pressso :that should eccentric pressures be applied to the platen there willbe `an indication of the existence of such a condition.

Itis still another object of this invention to provide a device including a pivotal platen on which there is mounted Vailig'ht Lbearn- ,source, ls uch platen beingV adapted to be gestaan?. finalit-.applicaties .at` @stemde pressures te a press movable platen or'thelike'to" project the Abearn'iof Zlll'l Patented Feb. 4, 1958 ICC lt is a further object of this invention to provide an indicating device connected to but remote from an hydraulic press having ra movable platen adapted to be actuated on the application of eccentric pressures to said platen to present to the operator a visible showing of a measure of the eccentric loading conditions.

These objects, as well as the various other novel features and advantages of this invention, will become apparent from the following description and accompanying drawings of which:

Figure l is a diagrammatical view showing the top and bottom press platens of a typical forging press and operatively connected thereto an indicating device incorporating the features of the invention herein disclosed, certain parts of both the press and the indicator being shown in perspective in order to illustrate the construction more clearly;

Figure 2 is a plan view of the indicating device shown in Figure l;

Figure 3 is a sectional plan view taken on lines III- lll of Figure 4, and

Figure 4 is an elevational sectional View taken on lines iV- IV of Figure 3.

With reference to Figure l of the above drawings, there is shown diagrammatically an hydraulic forging press having a top movable platen 8 and a stationary bottom platen 9. The top platen has connected thereto a plurality of main working piston cylinder assemblies 10 of which the four central ones are connected to a valve l1 and the four outer ones connected to a second valve 11n, the two valves 11 and 11a being in turn connected to a main solenoid valve l2 which communicates with a source of high pressure iluid not shown. By the Valve arrangement thus shown the total working pressure imposed upon the press platen may be varied in accordance with the operational requirements simply by opening one or both of the valves 11 and 11a. For sake of illustration a workpiece W is shown eccentrically placed between the platens 8 and 9 so that during forging there will be an eccentric loading imposed upon the platen of the press resulting in an eccentric moment tending to tilt the main press movable platen in a direction toward the right.

Inasmuch as the construction of the press forms no part -of this invention, the various parts comprising the press proper have not been described or illustrated in detail. However, there are shown four double acting balancing and pull-back piston cylinder assemblies 13, 14, 15 and 16 the piston rods of which are connected to the movable press platen 8 and the cylinders to the stationary lower press platen 9, such assemblies being employed to counterbalance eccentric moment forging conditions which may be imposed upon the movable press platen. It will be observed that in this arrangement diametrically opposite piston cylinder assemblies are interconnected with each other in such a fashion that the upper chamber of piston cylinder assembly 13 is connected to the lower chamber of the piston cylinder assembly 16 and the lower chamber of the piston cylinder assembly 13 connected to the upper chamber of the piston cylinder assembly 16. In like manner, the upper and lower chambers of piston cylinder assembly 14 are connected with the lower' and upper chambers respectively of the diametrically opposite piston cylinder assembly 15.

With reference in particular to the indicator as shown on Figures 2, 3 `and 4, a miniature indicating device -is illustrated comprisingV a .base-23 having a plurality of holes 24 therethrough at the four outer corners thereof and a series of smaller equally spaced openings 25 nearer itscenter and arranged lon a common circle. The larger openings 24 serve to receive a like number of vertically extended rods 26, the rods being threaded at their ends to receive a pair of nuts 27 which engage the opposite horizontal surfaces of the base 23 and secure the rods to the base. A similar construction is provided for acrossmember 28 arranged parallel to the base 23 and having a central aperture 29 therethrough, a series of holes 32 directly above and in line with the openings 25 in the base, an additional set of four openings 33, and four openings 34 at the outer corners and directly above the openings 27 in the base 23. The rods 26 pass through the openings 34 and by means of nuts 35 secure the rods 26 and the member 28 together. On the outer ends of the rods 26 and Vsecured thereto by nuts there is :a screen 36 vpreferably of a ground glass composition, the purpose `of which screen will be explained hereinafter. 4

Mounted on the base 23 there is a pedestal 37 with a top portion thereof recessed to form a socket or seat upon which there is received a spherical projection 38 extending downward from a pivotal rectangular-shaped lplaten The platen 39 is centrally located between the base 23 and the crossm'ember y28 and is maintained parallel thereto under ynormal operating conditions `by means of a plurality 'of pins 41 on opposite sides thereof which have enlarged rounded heads 43, each pin being surrounded by za compression spring 42 the constantof which is carefully calculated in order to provide the proper compressive action on actuation of the pivotal platen 39. Each pin 41 is slidably received in a-bushing 40 in order that the pin 41 will be free to moveon the slightest unbalanced conditions Which are imposed upon the platen 39. Each corner of the platen 39 is connected by means of a number of universal joints 44 to a like number of double acting piston-cylinder assemblies 45, 46, 47 and 48 secured to the top surface of the stationary crossmember 28 the rods 51 of which extend through the openings 33 of the crossmember 28 and are connected to the universal joints 44. It will be noted that the piston-cylinder assemblies through the universal joints connected thereto will assure positive vertical movement of the piston rods on the actuation of the pistons Within these assemblies. Centrally mounted on the top surface of the platen 39 there is a light 39a connected to a ybattery 41a which is so arranged as to project a beam of light through the aperture 29 to the screen 36.

With reference again to Figure 1, it will be observed that the` balancing and pull-back piston-cylinder assemblies 13 and 16 of the press are connected -to the corresponding piston-cylinder assemblies k'45 and 48 vof the indicator device and the piston-cylinder assemblies 14 and 15 connected to the piston-cylinder assemblies 46 and 47 thereof. It will be furthernoted that conduits 17 and 17a of the diametrically opposite piston-cylinder assemblies 16 and 13 and 48 and 45 are kso arranged that the -f bottom of piston-cylinder assembly v16 is connected to the bottom of piston-cylinder assembly '48 and the upper chamber of piston-cylinder assembly 13 with the upper chamber of piston-cylinder'assembly 45, thereby causing the platen 39 to tilt in a directionopposite to that at which the press platen 8 tends to tilt so that the effect will be to indicate by means ofthe beam of light on the ground glass screen 36 the relative location of the eccentric load imposed upon the press.

In order that the operator may 'know the extent of the eccentric loading conditions imposed upon the press platen two diamond-shaped areas or kerns 52 and :'13 are scribed or` otherwise marked out on the glass screen Y36 and of which the area 52 denes the acceptable or safe eccentric loading limits to which "the press maybe subjected and an area 53 the criticalo'rh-'dangerons I'eccentric loading conditions which maycause damage'to'the press. In the application for which lthis ind-icatoris .adaptedto be utilized, these patterned areasar'eso arranged that the major axis thereof is in proportion tofth'e length'o'f and.

lil

4 extends in the same direction as the major axis of the movable press Yplaten and the -minor -axis rthereof yis likewise proportionate to and -extends in the same direction as the minor axis of the press platen.

It will be apparent to those skilled in the art that other forms of indicators employing the principles of the invention disclosed herein may be utilized, however, for the sake of illustrating the present invention, the more simple form of indicator has been employed in which the glass screen will serve to indicate visibly the Yeccentric loading conditions of the press and, by reason of graduations placed upon the screen indicate 'the exact magnitude and direction thereof.

The operation "of the present invention may be briefly summarized as follows: On actuation of the press, the movable platen thereof moves downward and is maintained parallel to the stationary platen of the press so that the indicator platen 39 will be in perfect balance and 'the b'ea'm 4of light will be focused at the center of the 'kern 52. As shown in 'Figure 1, itwill tbe assumed that the workpiece 'to'be forged is located in a press offset position so kthat during the working stroke 'an'eccentric loading 'condition will be imposed upon the press. Inasmuch as the workpiece is located to the left of the center forging position, as shown 'in Figure 1, 'there will be a 'tendency for the right end of the platen '8 'to tilt downward and 'for the left end to remain relativelyrstatio'nary "on 'striking the workpiece. By 'this action, yuid from the top of piston-cylinder assemblies 13 and 14 will b'e I4discharged to the bottom of the piston-cylinder assemblies 15 and 16 thereby causing 'pistons of the last-'mentioned assemblies 'to 'rise or maintain their "positions until the left end of the platen Atravels sufficiently downward again to `'cause the platen of the press to attain aparallel relationship with respect to the stationary platen. At the same time that the balance and pull-back -pistoncylinder assemblies of the press platen are discharging and having `uid admitted thereto, a similar action takes place at the indicating device by virtue of the connecting conduits 17a, 18a, 21a and 22a, the conduits being 'so proportioned as to transmit a pressure to the complementary piston-cylinder Vassemblies of the indicator device, which pressure will be proportional to the pressures img posed upon the main pressbalance and pull-back pistoncylinder assemblies. Inasmuch as there willbe an unbalanced pressure condition in the piston-cylinder assem blies of the indicator device the indicator ,platen 39 will tilt 'in such a direction thatjthe'right lhand side thereof will 'move upward against the action of "the springs 42 tending to hold it in its level condition and the left 'hand side of the platen will move downward against the springs tendingto hold that sidelevel whereby'the beam of light will be projected'onto the screen 36 to theleft as 'shown and where -the'beam intercepts the screen'and the 'calibrated vareas or kerns thereof, there will be indicatedfto the operator the 'exact magnitude as wellas the direction of the eccentricloadi'ng of the press. Should vmany forging operationsbe carried out of the same'type,then the operator can arrange to'move the subsequent vvworkpieces in such Va 'manner as to finally A'obtain the best forging conditions for the particular. job rbeing undertaken. "Of'ic'ou'rse, if'th'epress is`to be used'lfor carrying out but one forging operationen a single workpiece, then therewould be'no necessity for considering 'the possibility of moving the dies'ortheworkpiece unless'the eccentric loading conditions should become 'so lsevere 'as to makeit advisable to 'd-iscontinuetheforging'operation `and relocate the vworkpiece so that the forging operation thereon can be completed.

In accordance with .the provisions of the patent statutes, I have explained the principleand operation 'of 'myinvention and have illustrated and described WhatIfc'onlsider to represent the best embodiment thereof. '-:How-

ever, Iidesireto have it understood thatwithin thesco'pe of the appended claims, the inventionimaybe practiced otherwise than as specifically illustrated and described."

I claim:

1. For use with a movable platen or the like an indi,- cator, means interposed between said indicator and said platen operably arranged to be inlluenced by an eccentric loading condition imposed upon 'said platen and independently of movement thereof to cause said indicator to denote a measure of the magnitude and direction of the eccentric loading condition."l

2. For use witha movable platen or -the like having means for applying `the necessary'w'orking pressure to said platen, a device forindicatingthe existence of an eccentric loading condition whichrnay be limposed upon said platen comprising means inlluenced by the imposition upon said movable platen of an eccentric loading condition and independently of movement of said platen for denoting a measure of the magnitude and the direction of such eccentric loading condition.

3. For use with a movable platen or the like'having pressure applying piston-cylinder assemblies connected thereto, an indicator including eccentric moment responsive means operably connected to said platen and adapted to be inllnenced by an eccentric loading condition imposed upon and independently of movement of said platen and so arranged to define a measureof such eccentric loading condition.

4. For use with a movable platen or the like means for establishing a pressure condition varying with the pressure imposed upon the platen, a source for producing an indicating light beam, a field on which said beam is impinged and means foractuating said ybeam producing source when an eccentric pressure is applied to and independently of movement of said platen so that the beam is caused to move on said lield to indicate the`ecc'entric application of pressure to said platen.

5. In combination with an hydraulic presslhaving a movable platen, a plurality of double-acting balancing and pull-back piston-cylinder assemblies secured to said platen with the diametrically opposite piston-cylinder assemblies being so arranged that the upper and the lower chambers of one cylinder are connected by fluid conductors to the lower and upper chambers respectively of the other, a device for denoting the existence of `an eccentric loading condition imposed upon the movable platen, p

said device comprising a movable member corresponding to the movable platen of the press, diametrically oppositely disposed means connected to and adapted to move said member and so connected to Ysaid piston-cylinder assemblies as to respond to diierentialpressures incident to an eccentric loading condition which in'ay be'imposed upon said platen, thereby to denote by movement of said member a measure of the magnitude and the direction of the eccentric moment condition `imposed upon said movable press platen.

6. An indicator in combination with an hydraulic press according to claim 1 in which there is included a beam producing source and a screen for intercepting said beam and having boundaries defined thereon for indicating by the position of the point of interception of said beam a measure of the magnitude and direction of the eccentric moment condition imposed upon said movable press platen.

7. In combination with an hydraulic press having a movable platen, a plurality of double-acting balancing and pull-back piston-cylinder assemblies secured to said movable platen, diametrically opposite piston-cylinder assemblies being so arranged that the upper and the lower chambers of one cylinder are connected by lluid conductors to the lower and upper chambers respectively f' 6?' indicator to denote a measure Aof the magnitude andthe direction of the eccentric loading condition imposed upon said platen.

8. In combination with an hydraulic press havingk a movable platen, a plurality of double-acting balancing and pull-back piston-cylinder assemblies secured to said platen with the diametrically opposite piston-cylinder assemblies being so arranged that the upper and the lower chambers of one cylinder are connected by Huid conductors to the lower and upper chambers respectively of the other, a device for ascertaining a measure of the magnitude and direction of an eccentric loading condition which may be imposed upon the movable platen which comprises a movable member corresponding to said platen, a plurality of piston-cylinder assemblies consisting of pairs diametrically opposite one another and corresponding to those secured to said press movable platen and with the upper and lower chambers of diametrically opposite piston cylinder assemblies of said device being connected to? gether in a fashion similar to that in which the corresponding piston cylinder assemblies of the press platen are connected, fluid connections between the press platen interconnected piston-cylinder assemblies and the interconnected piston-cylinder assemblies of the indicating device to which they correspond, and means remote from said member and so arranged with respect thereto as to denote the extent of the movement of said member and thereby a measure of the magnitude and direction of the eccentric loading condition imposed upon said press.

` 9. Inrcombination with an hydraulic press having a movable platen, a plurality of double-acting balancing and pull-back piston-cylinder assemblies secured to said movable platen with the diametrically opposite pistoncylinder assemblies being so arranged that the upper and the lower chambers of one cylinder are connected by fluid conductors to the lower and upper chambers respectively of the other, a device for determining a measure of the magnitude and direction of an eccentric loading condition which maybe imposed upon the movable platen of said press which comprises a member corresponding to the movable platen of the press, a plurality of pistoncylinder assemblies located in pairs diametrically opposite one another and corresponding to those secured to said press movable platen, a light beam producing source connected to said member, fluid connections between the press platen interconnected piston-cylinder assemblies and the interconnected piston-cylinder assemblies of the indicating device to which they correspond, a stationary screen for intercepting said beam and having a boundary defined thereon graduated to denote by the position of the light beam point of interception a measure of the magnitude and the direction of an eccentric loading condition imposed upon said movable press platen.

l0. In combination with an hydraulic press having a movable platen, a plurality of double-acting balancing and pull-back piston-cylinder assemblies secured to said movable platen with the diametrically opposite pistoncylinder assemblies being so arranged that the upper and the lower chambers of one cylinder are connected by uid conductors to the lower and upper chambers respectively of the other, a device for determining a measure of the magnitude and direction of an eccentric loading condition which may be imposed upon the movable platen which comprises a tiltable member corresponding to the movable platen of the press, a plurality of piston-cylinder assemblies located in pairs diametrically opposite one another and corresponding to those secured to said press movable platen, the upper and lower chambers of diametrically opposite piston-cylinder assemblies of said device being connected together in a fashion similar to that in which the corresponding piston-cylinder assemblies of the press platen are connected, fluid connections between the press platen interconnected piston-cylinder assemblies of the indicating device to which they correspond, a light beam producing source mounted on said member, a sta- 1saisit-1590"? s .tionary screenarranged to .intercept said beam oflight andhaving a boundary defined-upon said screenandso graduated as to denote by the point of interceptionof said :beam of light-a measure of the magnitude and lthe direction of the press eccentric loading condition,

11. ln .combination with an hydraulicpress having a movable platen and a plurality of double-acting platen balancing and pull-back piston-cylinder assemblies associated therewith, an indicator for denoting a `measure of the magnitude and direction of aneccentric moment loading condition imposed upon saidpress movable platen Vcomprising a support, aplaten corresponding to said press movable platen and mounted upon said support, a plurality of eccentric moment responsive means corresponding'totliebalancing and pull-back piston cylinder assembliesfof .the press and connected to said indicator platen, means.interconnecting-said moment responsive means to said l.press platen pull-back and balance piston-cylinder assemblies lto cause a direct. proportional actuation of said indicator platenas a measure offan unbalanced loading condition which may be imposed upon said press platen, a light beam source mounted upon said indicator platen, a screen adjacent to said indicator platen and parallel thereto when the indicator platen is-in its normal position, said screen having an area described thereonv defining the permis-sive maximum eccentric .loading condition to which kthe press may be subjected, said light sourcenormally projected to a point at the center of said dened area and on movement of said indicator platen shifted to a point upon the screen to denote a measure of the magnitude and direction of an'eccentric loading condition imposed upon the press movable platen.

12. A combination according to claim l'l in which there are provided yieldable means engaging opposite sides-and adapted to resist tilting movement of said indicator platen.

13. In combination with an hydraulic press having a movable platen and a plurality of double-acting platen balancing and pull-back piston-cylinder assemblies associated therewith, an indicator for denoting a measure-of the magnitude and direction of an eccentric moment loading condition of said press movable platen including a support, a pedestal centrally carried by said support, a pivotal platen mounted on said pedestal and corresponding to said press platen, spring resistance means engaging the opposite longitudinal surfaces of said pivotal platen adapted to resist the movement thereof, a `plurality of eccentric moment responsive means corresponding to the balancing and pull-back piston-cylinder assemblies of the press liexibly connected to the corners of said pivotal platen, means interconnecting said moment responsive means to `said press platen balance and pull-back pistoncylinder assemblies to cause a tilting force to be imposed upon said pivotal platen proportional to an eccentric loading condition imposed upon said press platen, a light beam Vsource mounted on said .pivotal platen, a screen ciated therewith, an 'indicator including a base adapted to-supportlaplurality of upright members, across member, having -a centrally located aperture therethrough, arranged parallel to saidfbase andcarried by said-upright membersand a 'pedestalcentrally'supported by said base,

a pivotal V,platen #corresponding to said vpress platen mounted on said pedestal-between -said base and cross member andfreely-connected to'said :pedestal by means of 'a'ball and Vsocket joit,;yieldable means engaging the opposite longitudinal surfaces of said pivotal platen adaptedto resist .movement thereof, aplurality of eccentric moment responsive means corresponding to the balancing `and .pull-back piston-cylinder assemblies of the press'carriedby said'cro-ss member and'exibly connected to and adjacent the outer edges of ksaid vpivotal platen, means interconnecting -said moment :responsive means to said .press platen 'balance and .pull-back assemblies to 'cause fa tilting force to be 1imp0sedupon said pivotal platen-proportional to aneccentric loading condition im- Vposedu'ponsaid press platen,ailight beam source mounted on said indicator T platen, a'scree'n arranged on the opposite t'end'of said upright'm'embers and normally parallel to lsaidipivotal plate'n a'n'dlhaving-an area described thereon deining a measur'eff'theboundariesof the permissive maximu'mleecentric Ioadingto be imposed'uponthe press, said light beam being projected 'through said aperture and onto said defined area `and fon -rnovement of said pivotal platen directed to a point upon vthe screen to denote a measure of the imagnitude and direction of the eceentricloading conditionof thep'ress platen.

515. An indicator according to claim V1 in which the means interposed between said indicator and said platen comprises differential pressure transmitting means operably connected to said -movable platen and yto said indicator.

References 'Citedlin'fthe -le fof this fpatent "UNITED ISTATES PATENTS 181,554 Bostwick.. Aug. .29, 1876 2,283,447 MacMillin et-lal. May 19, 1942 2,616,185 White Nov. 4, 1952

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US181554 *Feb 25, 1876Aug 29, 1876 Improvement in baling-presses
US2283447 *Jul 23, 1940May 19, 1942Hydraulic Dev Corp IncPress brake
US2616185 *May 26, 1950Nov 4, 1952White Roy FSpacing gauge assembly for mill rollers
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3091147 *Jul 31, 1959May 28, 1963Holl Walter VGuide means for adjustable hydraulic press
US3096708 *Jan 11, 1961Jul 9, 1963Samuel M Langston CoMachines for performing operations on sheet materials
US3161044 *Nov 7, 1962Dec 15, 1964Davy & United Eng Co LtdIndicating load eccentricity in forges
US4184827 *Jan 23, 1978Jan 22, 1980General Electric CompanyApparatus for monitoring and controlling the operation of a dual platen press
US4199539 *Jan 23, 1978Apr 22, 1980General Electric CompanyMethod for monitoring and controlling the operation of a dual platen press
US5537919 *Dec 27, 1994Jul 23, 1996Maschinenfabrik J. Dieffenbacher Gmbh & Co.Measuring and control system for a continuously operating press
US6095307 *Mar 4, 1999Aug 1, 2000A. J. Rose Manufacturing Co.Method and apparatus for detecting press tool failure
Classifications
U.S. Classification100/99, 72/453.8, 72/31.1, 100/258.00A, 100/258.00R
International ClassificationB30B15/00
Cooperative ClassificationB30B15/0094
European ClassificationB30B15/00P