US 2890077 A
Abstract available in
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Description (OCR text may contain errors)
June 9, 1959 F. M. L11-TELL 2,890,077
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June 9, 1959 F. M. LITTELL 2,890,077
VACUUM PICKUP AND TURN-OVER DEVICE Filed Sept. 7. 1955 7 Sheets-Sheet 2 feder 'ri June 9, 1959 F. M. LITTELL vAcuuM PICKUP AND TURN-OVER DEVICE Sept, '7.
June 9, 1959 F. M. L11-TELL VACUUM PICKUP AND TURN-OVER DEVICE 7 Sheets-Sheet 4 Filed SePt- 7. 1955 m. no. uw.
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VACUUM PICKUP AND TURN-OVER DEVICE Filed Sept. 7, 1955 'T Sheets-Sheet 5 es n N1 M m u @A r w s w LA- ggg m June 9, 1959 F. M. I ITTELI. 2,890,077
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June 9, 1959 F. M. LrrTl-:LL
VACUUM PICKUP AND TURN-GVER DEVICE 7 Sheets-Sheet 7 Filed Sept. 7, 1955 United States Patent O VACUUM PICKUP AND TURN-OVER DEVICE Frederick M. Littell, Chicago, Ill., assignor to F. J. Littll Machine Company, Chicago, Ill., a corporation of linois Application september 1, 195s, serial No. 532,817
s claims. (ci. 294-65) The invention relates to material handling apparatus and has reference more particularly to a vacuum pickup and roll-over device characterized in that suction cups are provided for gripping a metal sheet or the like as a preliminary step to lifting the sheet, and wherein a rotatable shaft supports the cups and provides for their rotation about the shaft as an axis, whereby the lifted sheet can be bodily rotated and supported on top of the cups for safe transportation from place to place within the shop.
One of the main objects of the invention is to provide a relatively simple but practical device for handling large aluminum sheets such as may form the wing of an airplane, the present device incorporating suction cups for gripping the smooth top surface of the metal sheet so that the same may be lifted by the cups and bodily rotated approximately one hundred and eighty degrees for turning over the metal sheet whereby the same will then rest on top of the cups and can be safely transported as by means of an overhead crane from which the device may be suspended.
A further object of the invention is to provide a vacuurn pickup and turn-over device adapted to be suspended from an overhead crane and from which electricity may be fed to the device by a cable reel, the device incorporating a C-frame, a rotatable shaft which is journalled by the C-frame and which projects laterally from the respective sides thereof, and vacuum cups carried at the respective ends of the shaft, and wherein rotation of the shaft will bodily rotate the vacuum cups from a position depending below the shaft to a position located above the shaft.
Another and more specific object of the invention is to provide a sheet lifter and turn-over device wherein the main body portion of the device consists of a C-frame which journals the vacuum-cup supporting shaft, and wherein the said C-frame provides a housing for a vacuum tank, a housing for the motor mechanism for rotating the shaft, and a housing for the control mechanism for the device.
Another object of the invention is to provide a device as defined wherein each set of vacuum cups is articulatedly connected to a carriage which is fixed to the turnover shaft and wherein additional refinements relating to anti-friction means for the suction cups and to adjustable heel pins for the suction cups are provided, the improvements to the suction cups improving their suction grip on the metal sheet, whereas the adjustable heel pins positively prevent slippage of the metal sheet during the turn-over operation.
A further object is to provide a metal sheet handling device of the character described which will incorporate a pair of electric switches and cam members for selectively actuating the switches as the turn-over shaft is rotated, whereby rotation of the shaft is confined to approximately one hundered and eighty degrees of movement, the shaft being automatically stopped when the suction cups are located in either of their down suspended position or in their elevated supported position.
With these and various other objects in view, the invention may consist of certain novel features of construction and operation, as will be more fully described and particularly pointed out in the specification, drawings and claims appended hereto.
In the drawings which illustrate an embodiment of the device and wherein like reference characters are used to designate like parts.
Figure l is a top plan view of the vacuum pickup and turn-over device of the invention, with parts being shown in section to better illustrate certain constructioual details of the device;
Figure 2 is a front elevational view of the vacuum pickup and turn-over device as shown in Figure l, with the turn-over device in rotated position for suspending the vacuum cups and positioning them horizontally for gripping a metal sheet;
Figure 3 is an end elevational view of the device as shown in Figure 2 with parts of the C-frarne being broken away for illustrating the manner of incorporating a vacuum tank within the frame;
Figure 4 is an end elevational view similar to Figure 3 but showing the rubber suction cups in an elevated position and with a metal sheet supported thereon;
Figure 5 is a vertical sectional view taken substantially along line 5 5 of Figure 1 and illustrating details of the carriage and the articulated connection therewith of the rubber suction cups;
Figure 6 is a vertical sectional view taken substantially along line 6-6 of Figure 7 and illustrating the associated relation of the switch mechanism and the cam members for actuating said mechanisms;
Figure 7 is a vertical sectional view taken substantially along line 7 7 of Figure 1 and illustrating the manner of journalling the hub portion of a carriage on the rear axle housing, and the manner of supplying a sub-atmospheric pressure to the suction cups while permitting their rotation bodily about the turn-over shaft as an axis;
Figure 8 is a fragmentary bottom plan view illustrating the manifold connection for the flexible tubes leading to the suction cups;
Figure 9 is a vertical sectional view taken substantially along line 9--9 of Figure l0 and illustrating constructional details of one of the suction cups; and
Figure l0 is a bottom plan view of the suction cup as shown in Figure 9.
The vacuum pickup and turn-over device of the invention is shown in its entirety in Figures 1, 2, 3 and 4, wherein it will be seen that the device essentially consists of a main frame 20 generally in the shape of a C and which provides the main body portion of the device. A U-bolt such as 21 is securely iixed to the frame at the upper end thereof and the said frame together with the other parts going to make up the device are preferably suspended from an overhead crane by means of a chain and hook having connection with the said bolt 21. The present vacuum pickup and turn-over device requires electricity for its operation and since the device is adapted to he moved or transported from place to place by movement of the overhead crane, it is necessary to supply the same with electric current through flexible cables which may be wound on a cable reel provided by the crane. The said frame 20 essentially consists of arcuate top and bottom plates 22 and 23, side plates 24 and 25, a top end plate 26, and a bottom end plate 27. The said system of exterior plates is adequately reinforced and additionally joined to each other by means of certain inside plates such as 30 and 31 and 32 and 33. The C-frame is partitioned by the inside plates 30 and 31 in a manner to form a compartment within which is located the control instruments (not shown) through which the operator may actuate thedevice in a controlled manner, the said instruments being preferably fixed to a control panel such as 34 conveniently located for manual and visual access by the operator. The plates of the C-frame in combination with the inside plates 32 and 33 form a vacuum tank 35 which provides a source of sub-atmospheric pressure having connection through conduit means with the vacuum cups.
Whereas the vacuum pickup and turn-over mechanism of the device is supported from the end wall 27 of the C-frame, the top wall 26 has secured thereto a bracket which supports a plurality of counterbalancing weights so that the frame member and suction cups of the device may be horizontally balanced when suspended from the U-bolt 21. The bracket is indicated by numeral 36 and the same may be secured to end wall 26 in any suitable manner. One requirement is that the bracket extend forwardly of the end wall and that the same provide a receptacle 37 of box-like formation within which a plurality of counterweights such as 38 may be located. The number and size of the counterweights can be varied by the operator and since they are located well forwardly at the upper end of the C-frame, they function in a manner to satisfactorily counterbalarice the suspended frame and the heavy load of the metal sheet which may be lifted thereby. The counterweight container 37 provides the top Wall 39 on which is supported a pair of vacuum pumps identified by numerals 40 and 41. Either one or a pair of pumps may be provided. However, a pair is preferred since the vacuum tank can be quickly evacuated by operation of both pumps when preparing to initially operate the present device, and when an adequate source of sub-atmospheric pressure has been provided one of the vacuum pumps can be cut out and the device operated using only the one pump remaining. It will be i understood that both vacuum pumps and 41 are suitably secured to and supported `by top wall 39 and that said pumps have connection with the vacuum tank 35. Electricity is required for operating the pumps and, in fact, an electric motor is combined with each pump. For this reason, vacuum tank 35 has the metal tube such as 42 extending horizontally therethrough, the tube proiecting beyond plates 32 and 33 and being suitably secured to said plates so as to provide an absolutely air-tight seal. Electric wires from the control panel 34 extend through tube 42 and go to the motor-pump combinations for connection therewith in a conventional manner.
The mechanism for lifting the metal sheet and for rotating the sheet is supported from end wall 27 and essentially consists of a turn-over shaft 43 having suction cups such as 44 connecting therewith. More particularly, the turn-over shaft 43 is suitably housed within and journalled by the axle housing designated in its entirety by numeral 45, 'and which is conventional in its design and construction, being suitably supported from end plate 27 of the C-frame 20 by means of the plate structure 46. Said structure 46 forms a bracket providing a flat rear face for contact with and securement to end plate 27, whereas the forward projecting end of the bracket is suitably secured as by welding to the axle housing relatively adjacent the respective ends thereof. The bevel gear 47 is secured to turn-over shaft 43 centrally thereof and the said gear has meshing relation with the pinion 48 fixed to the end of drive shaft 5I). By means of the coupling 51 the drive shaft 50 is suitably secured to the speed reducing mechanism 52 interposed between the coupling and the electric motor 53. Operation of the electric motor 53 accordingly drives the shaft 50 and which in turn imparts rotation to the turn-over shaft 43.
The turn-over shaft 43 extends beyond the axle housing 45 at its respective ends and has operative connection with carriage structure at each end, to which the suction cups 44 are articulately connected. When the suction cups are placed in contact with the smooth top surface of a metal sheet and sub-atmospheric pressure is applied thereto, the sheet is securely gripped by the suction cups and the same may be lifted by the crane which is accordingly actuated in a manner to lift the C-frame of the device. Prior to the lifting operation, it will be assumed that the top surface of the sheet has been carefully inspected for the occurrence of any flaws or the like. Upon lifting of the sheet the same can be turned over by rotation of the turn-over shaft 43, and accordingly, the lifted sheet is thereafter supported by the suction cups in a manner as best illustrated in Figure 4. In this position of the sheet the former bottom surface of the same can now be carefully inspected, and then the sheet in supported position on the suction cups and having location within the C-frarne can be safely transported from place to place within the shop. The carriage structure at respective ends of the turn-over shaft and the articulated connection of the suction cups thereto will now be described.
As best shown in Figure 7, the axle housing 4S is reduced in diameter at its respective ends providing the necked-down end portions 55 and which are located beyond the integral flanges 54. The hub member 56 of a carriage bar 57 has telescoping relation with the necked-down portion 55 and the said hub member 56 is suitably journaled on the portion by the roller bearing structures 58 and 59. The end of shaft 43 has suitably welded thereto the end plate 60 and said plate is in turn releasably secured to hub member 56 by means of the securing bolts 61. Thus rotation of the turn-over shaft 43 is communicated through end plate 60 at each end of the shaft to the respective hub members 56 journalled for rotation on each end of the axle housing 45. Each hub member 56 is provided with a flange 62 located centrally of the hub member and projecting radially outwardly to provide means for securing the carriage 57 to the hub member and which is accomplished through the instrumentality of the securing ring 63 located centrally of and formed integral with each carriage. The ring 63 has contact with the outer face of the flange 62, the surface of both parts being `adequately finished for the purpose, and by means of the bolts 64 and nuts 65 the securing ring 63 and thus the carriage is bolted to hub member 56 and rotation of the turn-over shaft 43 is therefore imparted through the hub members 56 to the carriages 57.
The structure going to make up each carriage is best illustrated in Figures 2, 4, 5 and 9. The vertical plate 66 of each carriage, having the securing ring 63 integral therewith, is adequately reinforced by an edge plate 67 which gives to each carriage the shape of a T in cross section. At each end of the carriage, as best shown in Figure 9, a pair of trunnions 68 are welded to the surface of edge plate 67. The pin 70 extending through the pair of trunnions 68 journals the trunnion bar 7l to the respective ends of which the suction cups 44 are connected. It will be understood that a carriage is located at each end of the turn-over shaft and at respective ends of each carriage there is journalled a trunnion bar 71 which in turn supports a pair of said suction cups. Accordingly, the turn-over shaft produces rotation of a pair of carriages which in turn have connected thereto a total of eight suction cups.
Each trunnion bar is built up of a plurality of plates 72 and 73 which are in turn joined at their inner ends to hub 74 by means of top and bottom fastening plates such as 75 and 76. The construction of each trunnion bar is identical and therefore only one need be described. Also the articulated connection between each suction cup and the trunnion bar is the same so that the following description will apply to both connecting structures. At the respective ends of each trunnion bar a stud such as 77 depends therefrom, Figures 5 and 9, and said stud is apertured for receiving the support pin 78 by means of which the yoke 80 is pivotally connected to the trunnion bar. The set screws 81 securely fasten the yoke to the pin 78 in desired operative position thereon and by means of the limit bolts 82, which are adjustable by manipulation of the nuts 83, the degree of swinging movement of yoke 80 about pin 78 as an axis can be controlled. It will be noted that the pivot pin 78 extends parallel to the longitudinal axis of its respective carriage 57. A pair of transverse pins identified by numerals 84 and 85 extend from respective sides of each yoke 80 and thus said pins extend at right angles to pin 78 and transversely as regards their carriage. Each pin is held to its yoke 80 by means of a set screw such as 86, and the projecting outer ends of said pins 84 and 85 have pivotal connection with studs 87 and 88, respectively, projecting from the metal backing plate of a suction cup 44. Each suction cup is accordingly supported on an axis formed by the pins 84 and 85 which allows for pivotal movement of the suction cups about said axis. Further pivotal movement of each suction cup and its yoke 80 as a unit is permitted by means of the pivot pin 78 which is horizontally aligned with pivot axis 84, 85, but which is disposed at right angles thereto. In addition to the articulated connection of each suction cup with its respective end of a trunnion bar 71, as above described, it will be understood that each trunnion bar is supported :for pivotal movement with respect to its carriage by means of the trunnon pin 70 associated therewith. The pivotal movement of each trunnion bar is preferably limited by means of the limit bolts 90 threaded in base plate 67 and which are held in adjusted position by nuts 91.
The invention provides a plurality of heel pins identified by numerals 92 and 93 which function as safety members since they are adapted `to contact a side edge of the metal sheet and therefore prevent slippage of the metal sheet from the suction cups in the event the vacuum should fail during the turn-over operation thereon. As best shown in Figures 3 and 4, the pins 92 and 93 are independently mounted in a tubular housing 94 and 95, respectively, having formed integral therewith the webs 96 which terminate in the bracket 97 suitably xed to an end plate 98 of its respective carriage 57. Each of the pins 92 and 93 terminate in a shank portion to which the handle member such as 100 and 101 are respectively secured, the shank portion Within its housing having a coil spring 102 associated therewith and which resiliently projects its piu the maximum distance outwardly of its housing. However, the operator by grasping handle member, either 100 or 101, can retract the pins below the level of the metal sheet when it is desired to release the metal sheet from the suction cups.
The carriage structure at each end of the turn-over shaft is completed by supporting legs 104, each carriage being provided With two such legs. Each leg is suitably joined to a plate 105 having a fixed relation with vertical plate 66 of the carriage and end plate 98 at its end of the carriage. When the turn-over shaft 43 has so located the carriages that the suction cups 44 thereof depend downwardly in operative position for gripping a metal sheet, it will be understood that the supporting legs 104 are inoperative at this time since, as evident from Figure 3, the supporting legs project upwardly. However, when the sheet which has been gripped and lifted by the suction cups has been turned over to assume the position as shown in Figure 4, the supporting legs 104 are now operative and the device may be lowered to a point where the supporting legs will contact the floor. The said legs accordingly relieve the carriage structure of the weight of the supported metal sheet since the weight can be transmitted by the legs to `the oor. In this supported position, with the Weight and strain of the metal sheet removed from the operative parts of the device, the sheet can be inspected and is otherwise stationarily supported until further operations thereon are ready to be performed.
The switch mechanism for controlling the rotating movement of the turn-over shaft 43 is best shown in `Figures l, 5 and 6. A limit switch 106 is provided for motor 53 to stop operation of the motor when the turnover shaft has reached the limit of its rotation in a clockwise direction, Figure 6, and a second limit switch 107 is provided to stop operation of motor S3 when the turn-over shaft reaches the limit of its rotation in a countcrclockwise direction. Said switches are suitably xed to bracket 108 which is in turn fixed to flange 54 at the right hand end of the axle housing, as shown in Figure l. The bracket 108 extends laterally to one side of flange 54 so that the limit switches and their rollerequipped actuating arm are properly positioned with respect to cam members 110 and 111. Limit switch 106 is provided with an actuating arm 112 which carries roller 113 at its `free end. In a similar manner limit switch 107 is provided with actuating arm 114 on the end of which is mounted the roller 115. The cam members 110 and 111 are secured by screws 109 to flange 62 projecting from hub member 66 at this end of the device. Accordingly, the cam members rotate with the turn-over shaft, whereas, the limit switches have a fixed position since they are secured to the stationary axle housing 45. In the position of the parts, as shown in Figure 6, the cam surface 116 of member 111 has engaged roller 115 to effect actuation of limit switch 107 and thus rotation of the turn-over shaft is stopped with the suction oups being located in depending position, rendering the device operative for gripping and lifting a metal sheet. When it is desired to rotate the metal sheet following the lifting operation thereon the operator presses a button closing the electric circuit to motor 53, whereupon the motor is energized and rendered operative for rotat ing the turn-over shaft in a clockwise direction. Rotation of shaft 43 will continue until cam member 110 is caused to engage roller 113 of limit switch 106. When the roller comes in contact with cam surface 117 of cam member 110 the limit switch 106 will be actuated to open the circuit to motor 53 and terminate rotation of the turn-over shaft. The switch 106 and cam member 110 are so positioned that clockwise rotation, Figure 6, of the turn-over shaft is stopped when the suction cups reach the horizontal elevated position as shown in Figure 4.
The vacuum tank 35 provides the source of sub-atmospheric pressure for the suction cups and the said tank is gards pipe 120, a support 122 is provided, having a fixed relation with flange 54 at this end of the axle housing for stationarily supporting the extension pipe 123, which connects with the rotorseal 124. The pipe 121 is similarly supported from flange 54 through the instrumentality of the sleeve 126 which extends through the bracket 108. The extension pipe 127 passes through the sleeve 126 and has connection at one end with the pipe 121 and at its opposite end with the rotorseal 124. The rotorseal structure at each end of the turn-over shaft is identical and it will be understood that the function of the rotorseal is to operatively connect the suction cups to the conduit means from the vacuum tank while permitting rotation of the suction cups for turning over the sheet gripped thereby. Each rotorseal, as shown in Figure 7, includes a body portion 128 which is centrally cored from one end and within which is located the stem 130 having the through passage 129. The stem is suitably journalled with respect to body portion 128 by the ballbearing assembly 131 and the seal 132 is resiliently held in contact with the inner terminal end of the stem by coil spring 133. The projecting end of stem 130 is threaded as at 134 and said threaded end has secured thereto the hose connection 135. Said hose connection may be formed of metal and the same is preferably arcuate in shape for conveniently joining the stern 130 with the manifold member 136 having location below hub portion 56 at its respective ends of the device and being suitably secured by screws 137 to base plate 67 of its respective carriage. The manifold member 136 is interiorly cored to provide a passage through the same and which has four outlets for threaded connection with sections of flexible rubber hose identified by numerals 140, 141 and 142, 143. The `four sections of exible hose have connection respectively with the four suction oups at their end of the turn-over shaft.
From the foregoing, it will accordingly be understood that whatever may be the position of the suction cups they will at all times have a conduit connection with the vacuum tank so that the face of each suction cup can be subjected to a pressure below atmospheric. The rotorseals 124 are required since part of the conduit means connecting the suction cups with the vaccum tank must rotate vnth the suction cups. Said parts include the manifold member 136 and the hose connection 135. The stern 130 of the rotorseal is able to freely rotate, notwithstanding that an adequate seal is maintained with respect thereto by the member 132 and coil spring 133.
The suction oups previously identified by numeral 44 are backed by a metal plate 144. Each cup is relatively shallow, having a flexible lip 45 and an interior face composed of a plurality of ribs 146 of zig-zag formation so as to form antifriction means. The ribs 146 are separated by grooves 147 of approximately the same width, and the ribs are so constructed and arranged that the grooves between the ribs form passageways having communication with the nozzle 148. Said nozzle extends through the backing plate 144 and has a secured relation with the lug 150 provided for the purpose. As clearly shown in Figure 5, the lug 150 receives threaded elbow 151, which in turn connects with a exible hose such as 142 and 143, as shown in said figure. The lip 145 of the cup is extremely flexible and when the cups are caused to contact the smooth surface olf a metal sheet the area within the lip is automatically sealed so that when the operator connects the cup with the source of sub-atmospheric pressure the vacuum created Within the shallow cup securely grips the cup to the sheet and the grip is maintained as long as the vacuum is maintained on the cup.
The main body portion of the present device is provided by the frame and the U-bolt 21 is provided in connection therewith so that the device may be suspended by an overhead crane through the instrumentality of the hook 152. The container 37 is essentially part of the frame since it is fixed to end wall 26 thereof and the container conveniently supports the vacuum pumps 40 and 41 and is adapted to receive a number of counterweights 38 for counterbalancing the load 0f the metal sheet 154 such as may be lifted by the device. The bracket structure 46 and the axle housing 45 may likewise be considered as part of the `frame since the same are fixedly secured thereto, having fixed relation with the bottom plate 27 of the frame. The journalling structure for each of the carriages is provided by hub member 56, which is mounted by means of ball bearings on the reduced ends respectively of the axle housing member 4S. The rotation imparted to the carriages and thus to the suction cups 44 connected thereto necessitates the provision of a rotorseal which serves to connect each of the pipes leading from the vacuum tank to the manifold member of the respective carriages and through the manifold member all of the suction cups for the particulnr carriage are Connected to the source of' sub-atmospheric pressure.
In operation the vacuum cups are placed in contact with the top surface of the sheet to be lifted and the operator by manipulation of a certain control on the control panel 34 connects the suction cups to the source of sub-atmospheric pressure. The vacuum thus created in each cup causes the cup to grip the plate or sheet and by actuation of the overhead crane the device and thus the gripped sheet can be lifted. The heel pins 92 and 93 are located on that side of the gripped sheet so that when the same is turned over by rotation of the turnover shaft 43 the pins will act as safety means having contact with the lower edge of the gripped sheet and thus preventing the same from slipping from the vacuum. cups should the sub-atmospheric pressure fail. When the sheet has been rotated for degrees, movement of the same is automatically stopped by actuation of the limit switch 106 and with the suction cups thus disposed in elevated position, it will be seen that the gripped sheet is horizontally supported on the cups and is located well within the base section of the frame 20 so that the sheet as thus supported can be safely transported by movement of the overhead crane from place to place within the shop.
The invention is not to be limited to or by details of construction of the particular embodiment thereof illustrated by the drawings as various other forms of the device will of course be apparent to those skilled in the art without departing from the spirit of the invention or the scope of the claims.
What is claimed is:
1. In a vacuum plate lifter and rotating device, in combination, a frame in the general shape of a C and providing a hollow body portion, means fixed to the frame at its topand for suspending the frame, an axle housing member fixed to the frame at the base thereof and extending laterally on respective sides of the frame, a turn-over shaft journalled by the axle housing member and extending from end to end for the length of the member, a carriage bar fixed to each end of the turnover shaft for rotation therewith and being disposed so as to extend on each side thereof, means journalling each carriage bar on its adjacent end of the housing member, a trunnion bar p-ivoted to the respective ends of each carriage bar and extending substantially parallel to the turn-over shaft, a suction cup located at the terminal ends respectively of each trunnion bar, means providing a universal joint for connecting each suction cup to its trunnion bar, and power means housed by the hollow body `portion of the frame and having a drive connection with the turn-over shaft.
2. A vacuum plate lifter and rotating device as defined by claim 1, additionally including at least one supporting leg fixed to each carriage bar and extending therefrom on the side opposite the suction cups.
3. A vacuum plate lifter and rotating device as defined by claim l, additionally including a heel pin carried by each carriage bar at one end thereof and disposed on the same side as the suction cups, a tubular housing member for each heel pin, resilient means within each housing member for forcing the heel pin into a projecting position beyond the plane of the suction cups, and a handle located at that end of the tubular housing opposite the projecting pin for retracting the heel pin against the tension of the resilient means.
4. In a vacuum plate lifter and rotating device, in combination, a frame in the general shape of a C and providing a hollow body portion, means fixed to the top end of the frame for suspending the frame, an axle housing member fixed to the frame at the base thereof and extending laterally on respective sides of the frame, a turn-over shaft journalled by the axle housing member and extending from end to end for the length of the member, a carriage bar fixed to each end of the turnover shaft for rotation therewith and being disposed so as to extend on each side thereof, journalling means for each carriage bar for mounting the same on its adjacent end of the housing member, a trunnion bar pivoted to the respective ends of each carriage bar and extending substantially parallel to the turn-over shaft, a suction cup located at the terminal ends respectively of each trunnion bar, means providing a universal joint for connecting each suction cup to it` trunnion bar, a source of vacuum within the hollow body portion, piping means connecting the vacuum source with each suction cup, additional means of the rotorseal type interposed in the piping means to permit bodily rotary movement of the suction cups due to rotation of the turn-over shaft, and motor means supported by the frame and having a drive connection with the turn-over shaft.
5. In a vacuum plate lifter and rotating device, in combination, a frame in the general shape of a C and providing a hollow body portion, means for suspending the frame, an axle housing member fixed to the frame at the base thereof and extending laterally on respective sides of the frame, a turn-over shaft journalled by the axle housing member, a hub member mounted for rotation on each end of the axle housing member and being fixed to its respective end of the turn-over shaft so as t0 rotate therewith, a carriage bar fixed to each hub member and being disposed normal to the shaft to extend on each side thereof, at least one suction cup articulatedly connected to each end of each carriage, power means supported by the frame and having a drive connection with the turn-over shaft, electric switches supported by the axle housing member adjacent one of the hub members, and cam means fixed to the said hub member and arranged to selectively actuate the electric switches.
References Cited in the le of this patent UNITED STATES PATENTS 1,296,079 Hitchcock et al. Mar. 4, 1919 1,519,243 Ericsson Dec. 16, 1924 1,801,305 Drake Apr. 2l, 1931 1,959,216 Owen May 15, 1934 2,380,306 Hallowell July 10, 1945