US3705647A

US3705647A - Apparatus for checking the circumferential edge surface and the diameter of disc-shaped objects

Info

Publication number: US3705647A
Application number: US100748A
Authority: US
Inventors: Ake Torgny Bergavist
Original assignee: Svenska Metallverken AB
Current assignee: Svenska Metallverken AB
Priority date: 1969-12-23
Filing date: 1970-12-22
Publication date: 1972-12-12
Anticipated expiration: 1989-12-12
Also published as: FR2073952A5; JPS4921209B1; GB1331976A; SE335431B; CA923300A; DE2061010A1

Abstract

An apparatus for checking disc-like objects for edge defects and deviations in the diameter of said objects from a pre-determined standard diameter. The apparatus includes a movement path for the objects being checked which is defined by two support members. The object supporting members are arranged to move in a parallelistic pattern of movement in relation to each other and are constantly biassed in a direction towards each other, the distance between said members being maintained at a pre-fixed magnitude by the object present in the movement path defined by said members. Also arranged in the vicinity of the movement path of said object is a pivot member, which is caused to be located in said movement path upon axial movement of one of said support members, whereby a defective object located in said path and contributing to said axial movement is pivoted over said pivot and rejected by the apparatus.

Description

United States Patent Bergavist [54] APPARATUS FOR CHECKING THE CIRCUMFERENTIAL EDGE SURFACE AND THE DIAMETER OF DISC- SHAPED OBJECTS [72] Inventor: Ake Torgny Bergavist, Finspang,

Sweden [73] Assignee: Aktiebolaget Svenska Metallverken, Vasteras, Sweden [22] Filed: Dec. 22, 1970 [21] Appl. No.: 100,748

[30]. Foreign Application Priority Data Dec. 23, 1969 Sweden ..17829/69 [52] US. Cl.... 209/88, 209/91 [51] Int. Cl. ..C10g 25/00 [58] Field of Search 194/102, 99; 209/88, 91, 82 v [56] References Cited UNITED STATES PATENTS 2,543,802 3/1951 Pechy ..-209/91 [15] 3,705,647 [45] Dec. 12,1972

2,716,487 8/1955 Cox ..209/91 Primary Examiner-Allen N. Knowles Attorney-Waters, Roditi, Schwartz & Nissen [57] ABSTRACT An apparatus for checking disc-like objects for edge defects and deviations in the diameter of said objects from a predetermined standard diameter. The apparatus includes a movement path for the objects being checked whichis defined by two support members. The object supporting members are arranged to move in a parallelistic pattern of movement in relation 18 Claims, 3 Drawing Figures APPARATUS FOR CHECKING THE CIRCUMFERENTIAL EDGE SURFACE AND THE DIAMETER OF DISC-SHAPED OBJECTS The present invention relates to an apparatus for checking the circumferential edge surface and the diameter of disc-shaped objects.

In the manufacture of precision-cut circular blanks from hard material, such as sheet metal, intended for subsequent use as coin blanks for example, it has hitherto been necessary to check the diameter and the edge surface of the blanks manually. With the speed of present day manufacturing techniques, however, it is not economically acceptable to gauge the accuracy of such blanks by hand, since this would require a far too large increase in checking personnel in order meet expanding demands at the same rate of growth. Moreover, manual checking is also undesirable from the point of view that defective blanks are sometimes overlooked as a result of deficient checking. It has therefore become necessary to fully automati'ze this operation and to reduce considerably the manual effort, and thereby the number of personnel required, to

' essentially that of a supervisory nature.

The subject of the present invention affords an apparatus by means of which the peripheral edgesurface and diameter of precision-cut circular, disc-shaped objects can be checked at very high speeds with a constant degree of accuracy which far surpasses that achieved by habitual action.

In accordance herewith, the present invention is mainly characterized by a chute-like structure which is flanked by two spaced, support members which are movable relative to each other and along which objects are intended to be passed one at a time while rotating around their center axis under the influence of a driving force created by the relative movement between the'two support members, of which two members one presents a support and rolling surface which engages at least a portion of the peripheral edge surface of a perfectly shaped object while the other of said two members presents, when viewed in section, a tapering groove, the respective flank surfaces of which form a supporting and rolling surface for respective corner edge portions of the object being checked, wherein at least one of said support members is movable in a parallclistic movement pattern in relation to the opposite support member to urge an object in said path towards said opposite support member and to subject said object to a moment of force with the fulcrum point situated on said opposite support member, and wherein located between the support members on the sideof the movement path for a correctly shaped disc is a fulcrum means which extends along the said support and rolling surfaces and which is in the form of a ridge, an oval raised portion or the like over which a defective disc is swung out of the chute as a reject.

The invention will now be described with reference to an embodiment thereof illustrated in the accompanying drawing, further characterizing features of the invention being disclosed in connection therewith.

FIG. 1 is a top plan view of an apparatus according to the invention for checking the cylindrical edge portions and diameters of disc-like objects produced by punching for example, and illustrates (a) the objects in a position of readiness, waiting to be fed to the apparatus, (b) with full lines a disc-like object being checked in accordance with the invention and occupying a first feed position, and (c) with broken lines a disc-like object occupying a disc-reject position in the apparatus.

FIGS. 2 and 3 are sectional views taken through the line I--l in FIG. 1, showing a disc being checked in a checking path extending through the apparatus and a rejected disc being removed from said path, respectively.

In the exemplary embodiment of the invention illustrated in the drawing, the reference numeral 10 identifies an inlet for discs 11 located in a position of readiness, from which they are fed to and checked in the apparatus. As shown in the drawing, the inlet 10 has a U- shaped profile, the upstanding members or flanks of which are in the form of two substantially

parallel guide strips

12 and 13 which guide the discs 11 one after the other towards-a withdrawable catch 14. The inlet 10, i.e., the U-shaped profile is covered over a region extending behind and infront of the catch 14 with a U- shaped cover plate 15, the side flanges 16 of which engage'around the external surfaces of the

guide strips

12 and 13. The main purpose of the guide plate 15 is to guide and direct each disc to be checked in the apparatus in a manner whereby the disc will initially take a correct position for a checking operation, which operation commences subsequent to the disc passing the catch member 14.

The means by which the disc-like object is checked comprises a chute or similar structure 17 which, in the exemplary embodiment, is arcuate in shape and to which the inlet 10 is connected substantially tangentially. The chute 17, which in the exemplary embodiment is assumed to be stationary, is defined externally by an arcuate flange 18 of relatively low height which merges substantially tangentially with a guide flange 19 which, together with a further edge-forming guide flange 20 positioned opposite said flange l9, and an intermediate support surface 21 defines an outlet 22 for checked, accepted discs leaving the apparatus.

Mounted for rotation around the same geometric center axis as that of the flange 18 of the chute 17 is a circumferentially grooved pulley or the like, generally shown at 23, which in addition to being able to rotate is also yieldingly movable in the direction of its geometrical axis, i.e., in a direction perpendicular to the plane of FIG. 1, a disc, e.g., the disc 24, which while rotating around its rotary axis is checked. in the chute 17, is yieldingly clamped with its peripheral edge abutting the inside of the arcuate flange 18 and with each sharp corner edge portion of the disc bearing against its respective flank surface of the opposing V-shaped flank surfaces of the pulley 23, as hereinafter described with reference to FIGS. 2 and 3. The disc 24 illustrated in FIG. 1 with full lines is assumed to be defective at 25, i.e., has an incomplete edge surface and'consequently shows an incorrect diameter when measured across its face. In the illustrated position, the disc 24 has just enteredthe checking chute 17 and since the imperfect portion 25 of the disc 24 is presumed to have not yet come into contact with either the flange 18 or the said flank surfaces (not shown in the Figure) of the pulley 23 it is retained in the chute in the same manner as though it were a perfectly round disc.

The disc is shown by broken lines, indicated at 240, in a position of continued advancement through the apparatus. In this position, however, the defective edge portion of the disc, here identified with the reference numeral 25a, is in contact with the flank surfaces of the groove extending around the periphery of the pulley 23. When the defective portion of the disc is thus positioned or when the defective portion occupies a position diametrically opposed to the illustrated position, i.e., is in contact with the arcuate flange 18, the checking means immediately detect the error in diameter and surface fault of the disc and reacts to swing the disc free from the chute 17 in a manner whereby the disc is ejected as a result of its pivoting, as will be described hereinafter in more detail with reference to FIGS. 1 and 2.

l The distinguishing feature of the checking means, however, is that each correctly formed disc is retained in the checking path throughout the entire distance from the catch 14 to the outlet 22, whereas a defective disc is ejected from the path 17, immediately a defective edge portion of the disc is rotated against the flange 18 or the flank surfaces of the groove in the pulley 23.

The discs 11 located in the position of readiness for feeding to the inlet move in the direction of arrow A without being rotated. Upon entering the chute 17, however, and subsequent to passing the catch member, the disc, for example the disc 24, is caused to rotate in response to the rotary movement of the pulley 23, the disc being forced to roll between the flank surfacesof the groove in the pulley 23 and the flange 18. In the event of a defective portion, such as at 25a, contacting either the flank surfaces of the groove or the flange 18, the disc while still rotating will be ejected from the chute 17 as a reject. Perfect discs, however, will rotate along the whole length of the chute 17 and be discharged through the outlet 22, which leads to a collecting station for checked and accepted discs, or directly to a station for continued treatment.

The above description of the apparatus illustrated in FIG. 1 has only explained the principle features of the construction and functioning of the checking apparatus, and a more detailed description of the various components of the apparatus will now be given with reference to the sectional views shown in FIGS. 2 and As will be seen from FIG. 2, the checking apparatus comprises principally a main body 26 provided with a shaft 27, wherein the body 26 on the shaft 27 are both through-passed in the longitudinal direction of the shaft 27 by a bore 28. Mounted for rotation and longitudinal movement in the bore 28 is a rotation spindle 29 for the pulley 23, the pulley being attached to one end of the spindle 29. The other end of the spindle is shown in the drawing by the reference numeral 30 and is rigidly connected with a drive shaft 31, which is powered or optionally manually driven so as to drive the spindle 29 of the pulley 23 in the direction of the arrow 32. The other end of the shaft 27 bears against a plate or the like 33 which is free in relation to the shaft 27 and the drive shaft 31 is provided with a corresponding annular flange 34, a pressure type coil spring 35 being arranged between plate 33 and the flange 34. The spring arrangement just described serves to pull the spindle 29 and the pulley 23 yieldingly in the direction of arrow B, either to stop position 36 or, alternatively, to a position in which the energy stored in the spring is substantially consumed.

In the embodiment of FIG. 2, it is assumed that a correctly formed disc 24b is located in the chute 17, in a position which corresponds substantially to the position of the imperfect disc 24a illustrated in FIG. 1. The disc 24b is held clamped between the flange 18 and the

flank surfaces

38 and 39 of the V-shaped groove 37 in the pulley 23 as a result of the pulley being moved through a short distance in a direction away from the main body 26 and because of compression of the spring 35. It should be noted that at least a portion of the peripheral cylindrical surface or edge of the disc is urged against the flange 18 while the sharp corner edge portions thereof bear against

respective flank surfaces

38 and 39 of the groove 37. The disc 24b is also supported, at least in the vicinity of the flange 18, by a support surface 40 located in the chute 17.

The disc 24b, which is conceived as being perfect with regard to its diameter and edge surface, will thus continue to rotate along the entire checking path in the chute 17, from the inlet 10 to the curved outlet 22 positioned beneath said inlet, through which outlet the disc finally passes to be conducted to a suitable collecting station for checked and accepted discs. This means that the distance between the pulley 23 and the stop 36 is maintained by the disc 24b being checked, the distance being maintained in a manner whereby all parts of a perfect disc and imperfect disc move along a movement path which is determined by a definite translational position of the pulley, i.e., with respect to an imperfect disc until a defective edge portion thereof, more specifically recesses in the edge of the disc, come into contact with either the flanks 38 and 39'or the flange 18. Immediately a defective portion of the disc comes into contact with the flanking members or the diameter of the disc deviates from the correct diameter, the force moment acting on the disc and established when the pulley is lifted by the force acting in the spring 35 will momentarily initiate downward movement of the pulley 23 to an extent corresponding to the magnitude of the defect while causing the imperfect disc to be tilted through a small angle around a point on the flange 18.

The operation of the apparatus when detecting imperfect edge portions of the disc will now be explained with reference to FIG. 3, like parts being identified with like reference numerals.

In the embodiment illustrated in FIG. 3, the imperfect disc 24a occupies the same position as that occupied in the embodiment of FIG. 1, which means that the local reduction in diameter of the disc 24a at the defective portion 25a (FIG. 1) is too large to enable the disc in this position to be retained in the path of movement for correctly formed discs. When the defective portion 25a of the disc 24a subsequently rolls into the groove 37 or against the flange 18, the pulley 23 will suddenly be incapable of retaining the disc in a path of movement corresponding to the path of movement of perfect discs, whereupon the spring 35 pulls the pulley downwardly towards the stop shoulder 36 and, as a result of the initiation of the aforementioned force moment the disc is tilted.

It can be mentioned in this connection thatarranged on the top of the main body 26 is a shoulder 41 which is concentric with the pulley and the flange 18 and which can be considered a stop member or fulcrum point about which the imperfect disc is tilted. The fulcrum point or stop 41 is arranged in a position whereby the upper portion thereof is substantially out of contact with a disc which rotates through the checking apparatus in the path of movement characteristic for discs having a correct periphery, but in a manner whereby imperfect discs, subsequent to rotating a certain distance through the checking path, are urged against the fulcrum by means or the pulley 23, when the disc is no longer able to move in the movement path for perfect discs, whereupon the discwill have for its point of rotation the fulcrum member 41 instead of the flange 18. As will be seen from FIG. 3, when the disc 24a engagesthe fulcrum member 41, it is lifted out of the checking path 17 whilepivoting around the fulcrum member, as shown in the Figure, and simultaneously rotates in a direction opposed to the direction of rotation of the pulley 23, which causes the disc 24a to be ejected from the chute 17 over the flange 18 and leave the apparatus as a reject.

It will be understood that even with the case of perfect discs there will always be slight deviations in their mutual diameters. Because of this only one disc can be properly checked at a time in the chute 17 of the apparatus of the present invention. For this reason the catch member 14 (FIG. 1 has been made to operate automatically so that the only one disc is found in the checking path at any one time. Thus, the catch 14 in the embodiments of FIG. 2 and 3 comprises a single wire spring which is secured to the under portion of the main body 26 by means of a curved portion 42. The other end of the spring presents a bent portion 43 located beneath and in contact with the underneath of the pulley 23.

It will be noted that the wire spring catch member, which is also shown in FIG. 2, is let into a substantially radially extending groove 44 in the main body 26. In the example illustrated in FIG. 2, the wire spring catch 14 is located out of the groove 44 and occupies a position in which it prevents another disc from entering the checking path while the disc 24 is present therein. In the position illustrated in FIG. 3, the disc 24a is no longer in the checking path, the pulley 23 being momentarily pulled down against the shoulder 36. The pulley 23 during this downward movement also acts upon the catch 14 to force it into the groove 44, whereupon it no longer blocks the entrance for the next disc arriving from the inlet 10. As soon as the next disc has been gripped between the flange l8 and the flank surfaces of the V-shaped groove in the pulley, the pulley is lifted as a result of the said engagement with the disc and the catch 14 automatically returns to the position in which it prevents the discs 11 located at the inlet from entering the checking path.

The invention has been described in the aforegoing with reference to an embodiment of a checking device having a circular checking path which extends over an arc of less than 360. Other constructions, however, are conceivable within the purview of the invention, for example such constructions in which the arc is either greater or smaller than the arc illustrated in the exemplary embodiment.

Neither is the invention restricted solely to checking paths which are arcuate in extension, but can also be applied expeditiously with checking paths which are substantially rectalinear, the. arrangement being defined, for example,.by a straight plate having alongitudinally extending flange of substantially the same construction or section as the flange 18 in the exemplary embodiment, and a second rectalinear plate having a longitudinally extending V-shaped groove located therein, the two members being constructed and arranged to operate in principle according to the characteristic features of the invention.

The size and cross-sectional shape of the flange 18 may be such that the height of the flange substantially coincides with the thickness of the disc, although is preferably smaller than the disc thickness. Moreover, the flange may present a surface along which the discs can roll, this surface being substantially oval in cross section, possibly in the formrof a rounded raised surface, or may also be of a certain, specific width. The surface may also be inclined in a manner whereby the whole of the disc is in contact therewith or only a part of the disc engages the surface.

The flange l8 and the flanking surfaces of the groove may lie at substantially the same level or be located at different levels. Finally, although the apparatus illustrated in FIGS. 2 and 3 is shown in a vertical position there is nothing to prevent the same from being inclined to the vertical in other, alternative desirable positions.

The invention is not restricted to the illustrated and described embodiment thereof, but can be modified within the scope of the following claims.

What we claim is:

1. An apparatus for checking the circumferential edge surface and the diameter of disc-like objects, characterized by a chute-like structure which is flanked by two spaced, support members which are movable relative to each other and along which objects are intended to be passed one at a time while rotating around their center axis under the influence of a driving force created by the relative movement between the two support members, of which two members one presents a support and rolling surface which engages at least a portion of the peripheral edge surface of a perfectly shaped object while the other of said two members presents, when viewedin section, a tapering groove, the respective flank surfaces of which form a supporting and rolling surface for respective corner edge portions of the object being checked, wherein at least one of said support members is movable in a parallelistic movement pattern in relation to the opposite support member to urge an object in said path towards said opposite support member and to subject said object to a moment of force with the fulcrum point situated on said opposite support member, and wherein located between the support members on the side of the movement path for a correctly shaped disc is a fulcrum means which extends along the said support and rolling surfaces and which is in the form of a ridge, an oval raised portion or the like over which a defective disc is swung out of the chute as a reject.

2. An apparatus according to claim 1, characterized in that the chute or like structure is provided with an inlet for unchecked objects and an outlet for checked and accepted objects, catch means being arranged to cooperate with said inlet to prevent the infeed of objects to the chute while an object is being checked therein, said catch means being arranged to be actuated out of its blocking position by at least one said support means as soon as an object has left the chute.

3. An apparatus according to claim 1, characterized in that the support members and the support and rolling surfaces associated therewith extend linearly.

4. An apparatus according to claim 1, characterized in that the support members and the support and rolling surfaces associated therewith have an 'arcuate extension, the center axes'of respective arcs coinciding with each other.

5. An apparatus according to claim 4, characterized in that one support member is non-rotatable and that the other support member is rotatable about said common center axis.

6. An apparatus according to claim 5, characterized in that the support and rolling surface of one support member extends along an arc of larger diameter than the diameters of the respective support and rolling surfaces of the other support member.

7. An apparatus according to claim 6, characterized in that the support and rolling surface of said one support member forms the support and rolling surface for at least a portion of the cylindrical edge portion of a correctly shaped object, and that the other support member consists of a pulley having an annular groove around the periphery thereof, the flanking surfaces of said groove forming the support surfaces for the sharp corner edges of the object.

8. An apparatus according to claim 7, characterized in that the pulley is mounted on a shaft which is arranged for rotary and translatory movement and which is concentric with the support and rolling surface of said one support member.

9. An apparatus according to claim 8, characterized in that the shaft is arranged to be yieldingly actuated for movement in an axial direction through a distance corresponding to the shortened distance between the support and rolling surfaces of the pulley and the support and rolling surface of said other support member.

10. An apparatus according to claim 7, characterized in the support and rolling surface of said one support member is stationarily arranged substantially in a radial plane relative to the geometric axis of the shaft and that the pulley is movable between several such radial planes.

1 1. An apparatus according to claim 7, characterized in that extending concentrically with the rolling surface of said one support surface is a raised circular fulcrum means which is located to one side of the movement path travelled by a correctly formed object between the support members and which projects into the individual movement path imperfectly formed object.

12. An apparatus according to claim 4, characterized in that at least one of the support and rolling surfaces extends obliquely to the common center axis of the support members.

13. An apparatus according to claim 4, characterized in that said one support member is provided with an object carrying surface, said surface suitably being located in the vicinity of the support and rolling surface of said support member.

14. An apparatus according to claim 4, characterized in that the support and rolling surface of said one support member extends along an arc of less than 360, and that guide rails are connected substantially tangentially to the ends of said are, said rails defining the inlet and outlet respectively of the chute defined by the support members.

15. An apparatus according to claim 14, characterized in that the rails are inclined downwardly said outlet, whereby checked and accepted objects are able to move under the force of gravity down to an underly-

Claims

1. An apparatus for checking the circumferential edge surface and the diameter of disc-like objects, characterized by a chutelike structure which is flanked by two spaced, support members which are movable relative to each other and along which objects are intended to be passed one at a time while rotating around their center axis under the influence of a driving force created by the relative movement between the two support members, of which two members one presents a support and rolling surface which engages at least a portion of the peripheral edge surface of a perfectly shaped object while the other of said two members presents, when viewed in section, a tapering groove, the respective flank surfaces of which form a supporting and rolling surface for respective corner edge portions of the object being checked, wherein at least one of said support members is movable in a parallelistic movement pattern in relation to the opposite support member to urge an object in said path towards said opposite support member and to subject said object to a moment of force with the fulcrum point situated on said opposite support member, and wherein located between the support members on the side of the movement path for a correctly shaped disc is a fulcrum means which extends along the said support and rolling surfaces and which is in the form of a ridge, an oval raised portion or the like over which a defective disc is swung out of the chute as a reject.

4. An apparatus according to claim 1, characterized in that the support members and the support and rolling surfaces associated therewith have an arcuate extension, the center axes of respective arcs coinciding with each other.

11. An apparatus according to claim 7, characterized in that extending concentrically with the rolling surface of said one support surface is a raised circular fulcrum means which is located to one side of the movement path travelled by a correctly formed object between the support members and which projects into the individual movement path imperfectly formed object.

14. An apparatus according to claim 4, characterized in that the support and rolling surface of said one support member extends along an arc of less than 360*, and that guide rails are connected substantially tangentially to the ends of said arc, said rails defining the inlet and outlet respectively of the chute defined by the support members.

15. An apparatus according to claim 14, characterized in that the rails are inclined downwardly said outlet, whereby checked and accepted objects are able to move under the force of gravity down to an underlying collecting station.

16. An apparatus according to claim 4, characterized in that the shaft is powered.

17. An apparatus according to claim 2, characterized in that the catch member consists of a wire spring which is attached at one end to said one support member and the other end of which is actuated by axial movement of the pulley to unblock the object inlet.

18. An apparatus according to claim 3, characterized in that the apparatus is adapted for checking coins or coin blanks.