US3316837A - System for the printing of spherical objects - Google Patents

Description

y 2, 1967 A. SCHECK 3,316,837

SYSTEM FOR THE PRINTING OF SPHERICAL OBJECTS Filed Feb. 4, 1966 5 Sheets-Sheet 1 INVENTOR. Arfur Scheck Attorney May 2, 1967 A. SCHECK 3,316,837

SYSTEM FOR THE PRINTING OF SPHERICAL OBJECTS Filed Feb. 4, 1966 5 Sheets-Sheet 2 n C I 1v" 92 I\ I0 0 IHI 1' 2 iq 1 pg" IXI Fig. 2

INVENTOR. Arfur Scheck Attorney y 2, 1967 A. SCHECK 3,316,837

SYSTEM FOR THE PRINTING OF SPHERICAL OBJECTS Filed Feb. 4, 1966 5 Sheets-Sheet 5 Arfur Scheck 1 N VEN TOR.

olUsS A q Aitom ey A. SCHECK 3,316,837 SYSTEM FOR THE PRINTING OF SPHERICAL OBJECTS May 2, 1967 5 Sheets-Sheet 4 Filed Feb. 4, 1966 INVENTOR.

a m C s r .w r A A tzorney y 2, 1967 A. SCHECK 3,316,837

SYSTEM FOR THE PRINTING OF SPHERICAL OBJECTS Filed Feb. 4, 1966 5 Sheets-Sheet 5 15 Tir ner I I 135 1 A36 Artur Scheck A ttorn ey United States Patent 3,316,837 SYSTEM FUR THE PRINTING 6F SPHERICAL OBJECTS Artur Scheck, Schaferstrasse 5, Gelsenkirchen- Buer-Sutum, Germany Filed Feb. 4, 1966, Ser. No. 525,059 Claims priority, application Germany, Feb. 4, 1965,

Sch 36,470; Aug. 19, 1965, Sch 37,582 10 Claims. (Cl. 101-115) ABSTRACT OF THE DISCLOSURE A system for printing spherical objects wherein a gripper means engages the sphere along its diameter while a plurality of rotatable silk screens successively engage the periphery of this sphere to rotate it about its spin was which, at each station, includes a different angle with the axis of rotation of the silk screen printing head. The grippers carry, via a conveyor, the sphere between the printing heads while swingable supports are provided for the grippers for angularly shifting the spin axis.

My present invention relates to a system for printing the surfaces of spherical objects or balls.

The general object of this invention is to provide means for printing at least the major part of the surface of a sphere, held in a suitable gripping device, without requiring repeated disengagement of the sphere from the device to permit a change in position, as is necessary with prior systems of this character.

A more particular object of my invention is to provide means for automatically or at least semi-automatically repositioning such a sphere, with reference to cooperating printing heads, in order to obtain the desired surface coverage.

A further object of the present invention is to provide automatic means for printing the entire surface of a sphere in a single operating cycle.

In accordance with this invention I provide a gripping device, preferably in the form of two relatively displaceable clamping arms, which engages a sphere to be printed at diametrically opposite poles so as to allow the sphere to rotate about a spin axis defined by these poles; there are further provided a plurality of printing heads, advantageously in the form of carriers for silk-screen matrices, which are rotatable about respective axes all differently inclined with reference to the spin axis of the sphere but coplanar with that spin axis so that the sphere can rotate jointly with a contacting printing head without undepgoing relative surface displacement. Thus, the pr1ntmghead axis may be parallel to the spin axis of the sphere, in which case the head will print an equatorial zone of the sphere upon being moved (radially or otherwise, in a plane bisecting the spin axis) into contacting position; for the printing of segmental zones adjoining this equatorial zone, on the other hand, the spin axis should intersect the printing-head axis and the printing head preferably is a substantially flat sector-shaped body moving tangentially to the sphere.

In this way, with the aid of a preferably cylindrical and a pair of sectoral printing heads, it is possible to print the major portion of the sphere surface, leaving free only two polar caps centered on the points of engagement between the sphere and the gripper arms. Advantageously, in conformity with a more specific feature of my invention, these printing heads are disposed at successive stations along a guide path over which the gripping device is moved by a suitable conveyor, a term broadly intended to include any mechanism adapted to entrain the gripper with stops at the several stations.

3,316,837 Patented May 2, 1967 According to this aspect of my invention, a support for the gripper is swingably mounted on the conveyor and is automatically displaced in a plane transverse to the path, as by a stationary track in camming engagement with an extension of the support, for placing the spin axis in a central (preferably horizontal) position at a first station, where the equatorial zone is printed, and for rotating this axis through an acute angle of, say, 45 on opposite sides of this central position on the approach to the further stations preparatorily to the: printing of the adjoining zones. Additional printing stations may be provided along the track if the sphere surface to be printed is to be subdivided into more than three segmental zones and/ or if more than one color is to be used for the printing of some of these zones.

As the gripper holding the sphere reaches the end of its guide path, at least its equatorial zone will have dried so thoroughly that it becomes possible to grasp the sphere at diametrically opposite points of that zone, thereby creating a new axis of rotation which exposes the polar regions and allows them to be printed at a terminal station. Thus, a grasping device disengaging the sphere from its gripper may rotatably present the sphere to the final printing head or may return the sphere to the gripper for the final printing step after a rotation through in a plane which includes the original spin axis.

The invention will be described in greater detail with reference to the accompanying drawing in which:

FIG. 1 is a somewhat diagrammatic top plan view of a system embodying the invention;

FIGS. 2 and 3 are cross-sectional views taken on the lines II-II and IIIIII of FIG. 1;

FIG. 4 is a view similar to FIG. 1, illustrating a modification; and

FIG. 5 is a cross-secti0nal view taken on the line V-V of FIG. 4.

The system shown in FIGS. 1-3 comprises a conveyor 1, here illustrated as a pair of parallel chains 1', pass ing around sprockets 36 and driven by a motor 37, which carries at spaced locations a number of transverse rails 2 of nearly semicircular configuration. The rails 2, bridging the parallel runs of conveyor chains are engaged by upper and lower rollers 38, 39 (FIG. 2) of respective carriages 3 which are journaled between parallel trapezoidal frames that constitute a lower carriage portion and straddle the associated rail, an upper carriage portion serving as a base for a gripper 4 with a fixed arm 4" and a movable arm 4 slidably mounted on that base. Arm 4' is traversed by a lead screw 5 which is rigid with a pinion 40 and a hand crank 41. Two saddle-shaped hubs 42', 42" are swivelably held in the tips of arms 4, 4" for engagement with opposite poles of a ball or sphere 6 defining an axis 11, this axis being swingable within the plane of rail 2 between one inclined position (FIG. 2), including an angle of 45 with the horizontal, through a horizontal position to an oppositely inclined position perpendicular to the one illustrated The surface of each ball 6 may be considered divided into five zones, i.e. an equatorial zone A, two adjoining segmental zones B, B" and two polar zones C, C" partly obstructed by hubs 42, 42". Four stations 20, 21, 22 and 23 are equispaced along the guide path defined by conveyor 1, the motor 37 being periodically arrested under the control of a timer 43 to align respective carrier rails 2 with these stations. An upwardly concave trough 44, fixedly underlying the upper run of conveyor 1, is formed with a meandering track 8 in the form of a groove engaged by a stud 7 which rigidly projects from the bottom of each carriage 3, the latter being thereby oscillated along its rail 2 as the conveyor moves on from one station to the next. More particularly, groove 8 lies midway between the chains 1', 1" at station 20 so that the carriage is centered by it into a position in which axis 11 is horizontal; at station 21 the stud 7 is cammed to the right (as viewed in FIG. 2), in station 22 the camming displacement is opposite so that the carriage has the position illustrated in FIG. 2, and in station 23 the centered position is re-established.

Station 20, which serves for the printing of equatorial zone A of a ball 6 clamped between the arms 4', 4" of a carriage 3, is provided with a printing head 24 comprising a cylindrical frame spanned by a silk-screen matrix 24a adapted to roll in contact with zone A when the head 24 is rotated through an arc of 360 or less about an axis a parallel to spin axis 11; head 24 is displaceable, in a plane transverse to this spin axis, on a piston rod of a hydraulic or pneumatic cylinder 45 which also carries an auxiliary cylinder 46 for imparting rotation to the head, in timed relationship with the operation of conveyor 1, under the control of timer 43. Head 24 may move radially of sphere 6 or skew to the axis 11, e.g. at an elevated level as illustrated in FIG. 3 for a similar printing head 32, located at station 23, which may be of the same general construction. The extent of rotation of head 24 is preferably so chosen that the ball 6 makes a full rotation about its axis so that zone A is completely printed.

At stations 21 and 22 there are provided two further printing heads 26 and 10, respectively, which are of substantially identical construction illustrated in detail in FIG. 2 for the head 10. This head comprises a planar sector-shaped frame spanned by a silk-screen matrix 10a, the frame being pivotally mounted on a fixed standard 9, rising alongside conveyor 1, by means of a shaft 12 which also supports a deformable wiper or squeegee 10b for vertical motion above the zenith of ball 6, i.e. in the plane of rail 2, when the ball-carrying assembly is in its temporarily arrested position at the station 22. A spring 13 on shaft 12 and a cam 14 rigid with head 10 co-operate to lower the squeegee 10b upon the ball, through the intermediary of screen 1011, after the latter has been swung into a position in contact with the ball surface. The swinging of the head 10 is accomplished by a linkage 15 connected with a piston rod of another hydraulic or pneumatic cylinder 16 likewise controlled by timer 43. As the head 10 rotates about an axis b it entrains the ball 6 to print the segmental surface B" thereof, adjoining the equatorial zone A; the symmetrically opposite zone B has already been printed, in like manner, in the preceding stage of the operating cycle by the head 26 of station 21; the respective swing axes b and b" of heads 26 and 1t) intersect the spin axis 11 at 45 angles substantially in the plane' of tangency of the deformable silk-screen matrix to the sphere. It will be understood that the printing ink on the successively treated zones dries during passage to the next-following zone so that smudging is prevented.

Before the sphere 6 can undergo final printing by head '32, it must be released from the gripper arms 4', 4" so that its hitherto untouched polar regions C and C can be exposed. For this purpose it is advantageous to have the saddle- shaped hubs 42, 42 weighted or otherwise biased (e.g. magnetically) so that they tend to assume a position in which the sphere is readily withdrawable in an upright direction after the spin axis 11 has been leveled. In the present embodiment I provide at station 23 a grasping device, generally designated 30, which includes a pair of arms 30a, 30b that are swingable about a horizontal shaft 31 and are pivotally secured to that shaft so as to be relatively movable by a cylinder 30c, likewise under the control of timer 43, for grabbing and releasing a ball 6 bracketed by the free ends of these arms.

The swinging of arms 30a, 30b is effected by means of another timer-controlled hydraulic or pneumatic cylinder 47 (FIG. 3) which operates, as soon as a ball 6 has arrived at station 23, to swing the tips of these arms from a remote position (dot-dash lines) into an axial plane of the ball in which hubs 48a, 48b on these tips confront diametrically opposite points of equatorial zone A to establish a new spin axis 49 transverse to axis 11. Actuation of cylinder 30c now brings the hubs 48a, 4817 into clamping engagement with these points whereupon the vertical-plane swing of the arms is reversed to withdraw the ball 6 from the gripper arm 4', 4" by swinging it into the position indicated in dot-dash lines. If the gripper arms are suffi-ciently yieldable, such withdrawal need not be preceded by a separation of these arms to disengage them from ball 6; in the system actually illustrated, however, I have represented a release mechanism by a rack 50 which is vertically movable by a timer-controlled cylinder 51 to engage the pinion 40 for rotating the lead screw 5 in a gripper-releasing sense. After the ball 6 has been lifted out of their grip, the rack 50 may again be withdrawn whereupon the gripper 4 continues on its way, eventually returning to starting station 2%) after a full conveyor revolution to be loaded with another sphere 6.

Ball 6, when elevated by the grasping device 30, confronts the printing head 32 whose support 52 carries a fluid-operated cylinder 33 under the control of timer 43. Cylinder 33 has a rod linked with a sector gear 53 which meshes with a pinion 54 on the shaft of the cylindrical head 32. The support 54 and the printing-head assembly carried thereon are jointly displaceable by means of a further timer-controlled cylinder 55 to establish contact between the outwardly swung ball 6, oriented by the weighted hubs 48a, 48b and the head 32. This printing head is thus rotatable about an axis d, parallel to axis 49, its deformable silk-screen matrix 32a turning through an are which frictionally entrains the ball 6 for at least a major fraction of a revolution; the rotation of the ball should, of course, be sufiicient to bring both polar regions successively into contact with screen 32a. A squeegee 32b is fixedly mounted inside this screen. As the annular zone swept by the printing head 32 intersects the zones A, B and B previously printed, it is possible to use this head to print additional portions-e.g. in different color-of these three zones. Cylinder 33 is similar to cylinder 45 at station 20, except for the longitudinal mobility of cylinder 46 together with head 24 under the control of cylinder 45.

After printing has been completed, and upon sufficient drying of the ink, the tips of arms 30a, 30b may be spread apart to release the ball 6 into a receptacle 56.

In FIG. 4 I have shown a generally similar system wherein, however, six stations 120, 121a, 122a, 121b, 12% and 123 are provided along the conveyor 1. Stations 121a, 121b have sectoral printing heads 126a, 126 h for the printing of zone B in two colors, stations 122a, 1221) being provided with sectoral printing heads a, 11Gb for a similar operation on zone B. Station 123 differs from station 23 of the preceding embodiment in that its grasping device 130 comprises a vertically movable suction cup 131 to which a partial vacuum may be applied by an exhaustor 152, this exhaustor being controlled by timer 43 along with a cylinder 133 whose piston rod 134 carries the cup 131. Stem 134 is, furthermore, provided with a linkage 135 connecting it with a rod of a timer-controlled cylinder 136.

The grasping device 130 is operated, upon the of a ball 6 at station 123, zenith of this ball and hold the latter by suction while the gripper arms 4, 4" are released as previously described (unless such release is made unnecessary by the resiliency of these arms). After the ball 6 has been elevated as shown in dot-dash lines (FIG. 5), cylinder 136 is actuated to rotate the stern 134 with cup 131 and ball 6 through 90 to establish a new spin axis perpendicular to axis 11. In this rotated position the ball is again lowered for re-engagement by the arms 4, 4" which, after release of the suction in cup 131 and upward withdrawal of stem 134, now hold the ball for rotary entrainment by a printing head 132 which is similar to head 24 and whose fluid-actuated cylinders 145, 146 are operated in like manner by the timer 43. The completely printed arrival to lower the cup 131 upon the.

ball may now be carried by the gripper 4 back to a station 35, ahead of station 120, where a release mechanism similar to that shown in FIG. 3 may open the gripper to let the ball drop into a receptacle not shown.

It can be easily shown that the sectoral printing heads 10, 26 etc. must extend over an are equal to 1rv'2, i.e. approximately 255 in order that the segmental zones B, B" should be completely printed; naturally, the extent of this are will vary with the angle of inclination of the axis 11 in the inclined position of FIG. 2.

I have thus disclosed a system in which the entire printing operation is performed automatically, except for the initial clamping of the balls in grippers 4 with the aid of cranks 41. It will be understood that a greater or lesser degree of automatization is possible and that various modifications may be introduced without departure from the spirit and scope of the invention as defined in the appended claims.

I claim:

1. A system for printing spherical objects, comprising gripper means for engaging a sphere at diametrically opposite poles with freedom of said sphere to rotate about a spin axis defined by said poles; a plurality of rotatable printing heads including respective carriers for silk-screen matrices successively engageable with the periphery of said sphere, said heads being rotatable about respective axes all differently inclined with reference to said spin axis but coplanar therewith; means for shifting said spin axis between successive engagement of said heads with said sphere; and means for jointly rotating said sphere and the printing head in contact therewith whereby each of said heads prints a respective segment of said sphere centered on said spin axis.

2. A system for printing spherical objects, comprising gripper means for engaging a sphere at diametrically 0pposite poles with freedom of said sphere to rotate about a spin axis defined by said poles; a plurality of rotatable printing heads successively engageable with the periphery of said sphere, said heads being rotatable about respective axes all differently inclined with reference to said spin axis but coplanar therewith; means for jointly rotating said sphere and the printing head in contact therewith whereby each of said heads prints a respective segment of said sphere centered on said spin axis; and conveyor means coupled with said gripper means for entraining same together with said sphere over a predetermined path, said printing heads being disposed at successive stations along said path, said gripper means being provided with swingable support means for turning said spin axis into diflerent angular positions within a plane transverse to said path.

3. A system as defined in claim 2 wherein said printing heads comprise carriers for silk-screen matrices.

4. A system as defined in claim 2, further comprising a stationary track extending along said path, said support means being provided with an extension cammingly engaging said track for swinging said gripper means within said transverse plane between successive stations.

5. A system as defined in claim 4 wherein said support means comprises a substantially semicircular rail on said conveyor means and a carriage movable along said rail through an are between and said carriage being rigid with said extension.

6. A system as defined in claim 5 wherein said gripper means comprises a pair of relatively movable arms mounted on said carriage.

7. A system as defined in claim 4 wherein said stations include a first station whose printing head is roatable about an axis parallel to said spin axis in a central position of the latter and displaceable in a plane bisecting said spin axis for printing an equatorial zone of said sphere, and at least two further stations in which said spin axis is displaced by an acute angle on opposite sides of said central position, the printing heads of said further stations being sector-shaped and movable tangentially to said sphere for printing annular zones adjoining said equatorial zone.

8. A system as defined in claim 7 wherein said stations include a terminal station provided with grasping means for disengaging said sphere from said gripper means, thereby exposing polar regions of said sphere, and presenting said polar regions to the printing head of said terminal station.

9. A system as defined in claim 8 wherein said grasping means has arms engageable with said sphere along diametrically opposite equatorial points thereof, said sphere being rotatable about a diameter defined by said equatorial points during contact with the printing head of said terminal station.

10. A system as defined in claim 8 wherein said grasping means is reciprocable in a direction perpendicular to said spin axis and rotatable through 90 about said direction upon withdrawal of said sphere from said gripper means for returning said sphere to said gripper means in an angularly offset position preparatorily to contact be tween said sphere and the printing head of said terminal station.

References Cited by the Examiner UNITED STATES PATENTS FOREIGN PATENTS 7/1933 France.

ROBERT E. PULFREY, Primary Examiner. WILLIAM F. MCCARTHY, JR., Examiner. H. P. EWELL, Assistant Examiner.

Claims (1)

1. A SYSTEM FOR PRINTING SPHERICAL OBJECTS, COMPRISING GRIPPER MEANS FOR ENGAGING A SPHERE AT DIAMETRICALLY OPPOSITE POLES WITH FREEDOM OF SAID SPHERE TO ROTATE ABOUT A SPIN AXIS DEFINED BY SAID POLES; A PLURALITY OF ROTATABLE PRINTING HEADS INCLUDING RESPECTIVE CARRIERS FOR SILK-SCREEN MATRICES SUCCESSIVELY ENGAGEABLE WITH THE PERIPHERY OF SAID SPHERE, SAID HEADS BEING ROTATABLE ABOUT RESPECTIVE AXES ALL DIFFERENTLY INCLINED WITH REFERENCE TO SAID SPIN AXIS BUT COPLANAR THEREWITH; MEANS FOR SHIFTING SAID SPIN AXIS BETWEEN SUCCESSIVE ENGAGEMENT OF SAID HEADS WITH SAID SPHERE; AND MEANS FOR JOINTLY ROTATING SAID SPHERE AND THE PRINTING HEAD IN CONTACT THEREWITH WHEREBY EACH OF SAID HEADS PRINTS A RESPECTIVE SEGMENT OF SAID SPHERE CENTERED ON SAID SPIN AXIS.

Images