US3201218A

US3201218A - Plunger type glass feeding apparatus

Info

Publication number: US3201218A
Application number: US162335A
Authority: US
Inventors: Frederick J Wythe
Original assignee: Newfrey LLC
Current assignee: Newfrey LLC
Priority date: 1961-12-27
Filing date: 1961-12-27
Publication date: 1965-08-17
Anticipated expiration: 1982-08-17
Also published as: GB967225A; CH382381A

Description

Aug. 17, 1965 F. J. WYTHE 3,201,218

PLUNGER TYPE GLASS FEEDING APPARATUS Filed Dec. 27. 1961 H al I 72 I 0 l W70 I H:

/2 F 62 01 H I \B/LJ' f @m '58 I F 26 22 W1 i 1 42 44 5 60 J40 24 O /O O j h a: 50

EXHAUST PRESSURE M INVENTOR. FREDERICK J. WYTHE BYJ;@,%M 074W EXHAUST ATTORNEYS plunger and wherein the force of feeding apparatus to which the "plied includes a vertically reciprocable bracket for sup- United States Patent 3,201,218 PLUNGER TYPE GLASS FEEDING APPARATUS Frederick J. Wythe, Hebron, Conn., assignor to Emhart Corporation, a corporation of Connecticut Filed Dec. 27, 1961, Ser. No. 162,335 3 Claims. (Cl. 65-330) I feeding mechanism of the type wherein a rotating cam, a

cam follower and a lever linkage are used to lift the gravity is relied upon for the downward movement of the plunger, a fluid motor for assisting both movements of the plunger so as to provide better control of the plunger force and to assure positive cam and cam follower contact at all times.

As will be described in more detail hereinafter, the glass present invention is apporting the plunger. The bracket is mounted on a vertically reciprocable post which is moved upwardly by a 1 lever when the lever is pivoted by a cam follower engaging the bottom side of a rotating driven cam. A glass feeding apparatus of this type is shown in US. Patent No. 2,654,184 and in US Patent No. 2,749,665, and it will be seen from these patents that the Weight or gravity force of the plunger, bracket, post, etc. is relied upon to effect the downward movement of the plunger.

It is particularly desirable to assist plunger movement in the downward direction to overcome the resistance of partially cooled but nonetheless molten glass. To this 'end, a fluid motor comprising a cylinder and piston is mounted on a non-moving part of the apparatus with its piston rod connected to the lever to assist in plunger movement. The fluid motor is preferably reversible and it is controlled by a two-position valve. The valve has .a rack formed thereon which is engaged by a pinion formed on one end of a shaft whose rotation is retarded by a slip clutch. The preferred form of slip clutch comprises a magnetic hysteresis brake operable within a housing which is mounted on the bracket for vertical movement. During initial bracket and plunger movement in either direction, there will be no relative movement of the pinion and rack because of the retarded shaft and thus the valve will be shifted to one of its two positions. After the valve has reached the limit of its movement and is placed in one of its two positions, the brake or clutch will slip to permit relative rack and pinion movement.

Therefore, the fluid motor is reversed to assist in plunger and bracket movements in either direction respon- FIG. 1 is an elevational view of a portion of the glass feeding apparatus and it shows all of the elements thereof that have heretofore been mentioned; and

FIG. 2 is a schematic cross-sectional view showing the clutch and control valve structures.

As shown in FIG. 1 and as more fully shown and described in U.S. Patent 2,749,665, the plunger 10. is

mounted on one end of an arm 12 which is adjustably supported on a bracket 14 for vertical reciprocation therewith relative to a bowl 16. The bowl 16 is a receptacle for molten glass which is discharged therefrom through a bottom opening 18 in the bowl, the said opening being defined by an orifice ring 20. The glass is discharged as a result of the vertical reciprocation of the plunger 10 over the opening 18 and substantially along the vertical axis thereof.

The plunger is connected to the end of the arm 12 by clamping means indicated generally by the reference numeral 22, this forming no part of the present invention and being shown and described in Patent 2,749,665. The bracket 14, the arm 12 and the plunger 10 are vertically reciprocated as a result of vertical reciprocation of a shaft or post 24 to which the bracket 14 is rigidly connected. The post 24 is moved upwardly and downwardly through upper and

lower bushings

26 and 28 which are a part of the fixed frame of the apparatus, the said frame being designated throughout by the letter F.

Mechanical means is employed to lift the post 24 and thus the bracket 14 and plunger 10. Accordingly, this means is indirectly connected with the plunger, and as shown in FIG. 1, it includes a cam 30 which is secured to a cam shaft 32 for driven rotation in a counterclockwise direction. The mechanical means for lifting the plunger also includes a cam follower comprising a roller 34 engaging the bottom side of the cam 30, the roller being supported on the end of a pivoted arm 36 and being further supported on a pair of straps which straddle the cam, one of the straps being designated by the numeral 38. The straps have extensions such as shown at 40 which project upwardly and journal a roller 42 engaging the upper arcuate surface 44 of a lever 46. The lever 46 is pivotally mounted at 48 to the frame F and the arcuate surface 44 thereof is formed on a radius from the center of the cam-following roller 34 when the said roller is on that portion of the cam periphery nearest the cam axis.

On the opposite side of the pivot point 48 from the arcuate portion 44, the lever 46 has a portion 50 which is bifurcated at its end to straddle the vertically movable post 24. The said bifurcated end is pivotally connected to a pair of linkages, such as the link 52, which are pivotally connected at their other ends to a pin 54 which is secured transversely in the post 24. Therefore, upon clockwise pivoting movement of the lever 46 as viewed in FIG. 1, the post 24 will be lifted and this lifts the plunger 19 and the bracket 14.

It will be seen that the lever 46 is pivoted in the clock wise direction to lift the plunger when the cam following roller 34 rides upon the radially outer portions of the periphery of the cam 39. The magnitude of lifting movement or stroke of the plunger it) varies in proportion to the distance separating the axis of the lever actuating roller 42 from the lever pivot axis 48. This distance can be adjusted to adjust the stroke by means of a manually operated screw 56 which is threaded into the support for the lever actuating roller 42.

As has been said, and as will be seen from the drawing, the return or downward stroke of the plunger 10 is caused primarily by the gravity force or weight of the plunger, the bracket 14, the post 24 and the associated vertically movable elements. As has also been said, both movements of the plunger 10 are assisted by a fluid 7 motor identified by the numeral 58 on the drawing. The

said fluid motor comprises either an hydraulic or pneumatic cylinder which is supported on the frame F for substantially vertical movement of a piston having a rod eX- tension 60 which is pivotally connected with the lever 46 on the portion 50 thereof. A fluid conduit 62 is connected to the upper end of the fluid motor cylinder and a similar fluid conduit 64 is connected to the lower end of the said cylinder. These conduits extend from a control valve housing 66 which is mounted on the frame F. As will be described more fully, the control valve functions to connect the fluid conduit 62 to a source of fluid funder pressure while exhausing fluid from the conduit sist clockwise movement of the lever 46 and lifting movement of the plunger 10.

As shown in both figures of the draWing, the two-position valve 68 which is operable within the valve housing 66 has a gear rack extension 70 formed thereon and which is reciprocated by a slip clutch indicated generally at 72 to place the valve in its one end other positions. The preferred slip clutch "12 comprises a magnetic hysteresis brake and it includes a housing 74 which'is supported on the bracket 14 for vertical movements therewith. The clutch also includes an armature 76 which is keyed to a shaft 78 having a pinion 80 formed on its outer end to engage the rack 70. The clutch or brake is normally energized to retard rotation of the armature 76 and the shaft 78 whereby upon initial movement of the plunger and bracket and thus the clutch housing 74, the retarded shaft and pinion 80 will not rotate and thus the rack 70 and valve 68 will be moved responsive to initial movement of the plunger. That is, when the plunger starts to move downwardly thevalve 68 will be placed in its one position at the limit of its downward movement. Thereafter, the armature 76 will slip and relative movement will take place between the pinion 80 and the rack 70. When the plunger 10 starts to move upwardly, the retarded clutch armature and shaft will cause the rack and valve 68 to be moved upwardly to the limit of its movement within the housing 66, thus placing the valve in the other of its two positions. Thereafter, continued upward movement of the plunger will cause clutch slippage and there will'be relative rack and pinion movement.

As will be observed with reference to FIG. 2, when resulting from initial downward movement of the plunger 10, it will direct fluid under pressure from a source into the conduit 62 to the top of the fluid motor 58 to assist in the downward movement and to help maintain the plunger 10 in its down position. At the same time, the valve 68 will connect the conduit 64 to an exhaust port. When the valve is in its other or up position, the conduit 64 will be connected to the pressurized source while the conduit 62 is exhausted. It will be noted that the valve is connected to a tension spring 82 tending to place it in its other or up position. This is so arranged to effect upward movement of the plunger 10 or to assist in such upward movement to avoid freeze-up of the plunger in the bowl outlet whenever the glass feeding apparatus is not being operated.

In most installations, it is desirable to limit the upward force applied by the fluid motor 58 to less than the weight of the plunger, the bracket, and the associated vertically movable elements. The purpose for this is to assure that positive contact will always be maintained, due to the force of gravity, between the cam follower 34 and the cam 30. In such installations, it will be necessary to stop the operation of the feeder mechanism with a radial distant point on the periphery of the cam 30 engaging the follower 34 in order to assure that the plunger 10 will be elevated.

"the valve 68 is in its one position, i.e., the down position The means limiting the upward force of the fluid motor 58 comprises pressure limiting means in the form of a valve 84 which is disposed in an exhaust conduit 86 tapped into the conduit 64. Thus, whenever the pressure in the conduit 64 exceeds a predetermined level, the valve 34 will open to reduce the pressure in the conduit 64 to the level wherein the resultant upward force is less than the applied force of gravity.

The invention claimed is:

1. In glass feeding apparatus of the type which includes a bowl having a bottom opening for the discharge of molten glass as a result of vertical reciprocation of a plunger over the opening, and wherein plunger lifting is effected primarily by mechanical means connected with the plunger and including a rotating cam while downward movement is caused by gravity, improved means for assisting plunger movement in both directions and comprising a reversible fluid motor connected with the mechanical means, a two position control valve operatively connected with said fluid motor, and valve actuating means comprising a magnetic clutch having a housing mounted for movement with the plunger and also having a' retarded shaft provided with a pinion, and the valve being provided with a rack engaged by the pinion whereby during initial downward movement of the plunger there is no relative rack and pinion movement so that the valve is placed in one position to effect a fluid motor assist to such plunger movement and thereafter the clutch slips to permit relative rack and pinion movement, and

whereby during initial upward movement of the plunger there is no relative rack and pinion movement so that the valve is placed in its other position to effect a fluid motor assist to such plunger movement and thereafter the clutch slips to permit relative rack and pinion movement.

2. Improved means for assisting glass feeder plunger movement as set forth in claim 1 and wherein fluid pressure limiting means is operatively connected with said valve and fluid motor to limit the lifting force provided by the fluid motor to less than the, gravity force.

3. In glass feeding apparatus of the type which includes a bowl having a bottom opening for the discharge of molten glass as a result of vertical movement of a plunger over the opening; and wherein the plunger is supported on a vertically reciprocable bracket which is lifted by a rotating cam, cam follower and lever connected with the bracket while downward movement thereof is caused by gravity; improved means for assisting plunger reciprocation in both directions and comprising a reversmeans operatively connected with said valve and fluid motor to limit the lifting force provided by the fluid motor to less than the force of gravity.

References Cited by the Examiner UNITED STATES PATENTS 2,725,681 12/55 Wythe 65-330 2,749,665 6/56 Peiler 65-330 2,902,612 9/59 Whearley 310- 2,912,607 11/59 Duncan 310-99 DONALL H. SYLVESTER, Primary Examiner,

Claims

1. IN GLASS FEEDING APPARATUS OF THE TYPE WHICH INCLUDES A BOWL HAVING A BOTTOM OPENING FOR THE DISCHARGE OF MOLTEN GLASS AS A RESULT OF VERTICAL RECIPROCATION OF A PLUNGER OVER THE OPENING, AND WHEREIN PLUNGER LIFTING IS EFFECTED PRIMARILY BY MECHANICAL MEANS CONNECTED WITH THE PLUNGER AND INCLUDING A ROTATING CAM WHILE DOWNWARD MOVEMENT IS CAUSED BY GRAVITY, IMPROVED MEANS FOR ASSISTING PLUNGER MOVEMENT IN BOTH DIRECTIONS AND COMPRISING A REVERSIBLE FLUID MOTOR CONNECTED WITH THE MECHANICAL MEANS, A TWO POSITION CONTROL VALVE OPERATIVELY CONNECTED WITH SAID FLUID MOTOR, AND VALVE ACTUATING MEANS COMPRISING A MAGNETIC CLUTCH HAVING A HOUSING MOUNTED FOR MOVEMENT WITH THE PLUNGER AND ALSO HAVING A RETARDED SHAFT PROVIDED WITH A PINION, AND THE VALVE BEING PROVIDED WITH A RACK ENGAGED BY THE PINION WHEREBY DURING INITIAL DOWNWARD MOVEMENT OF THE PLUNGER THERE IS NOT RELATIVE RACK AND PINION MOVEMENT SO THAT THE VALVE IS PLACED IN ONE POSITION TO EFFECT A FLUID MOTOR ASSIST TO SUCH PLUNGER MOVEMENT AND THEREAFTER THE CLUTCH SLIPS TO PERMIT RELATIVE RACK AND PINION MOVEMENT, AND WHEREBY DURING INITIAL UPWARD MOVEMENT OF THE PLUNGER THERE IS NO RELATIVE RACK AND PINION MOVEMENT SO THAT THE VALVE IS PLACED IN ITS OTHER POSITION TO EFFECT A FLUID MOTOR ASSIST TO SUCH PLUNGER MOVEMENT AND THEREAFTER THE CLUTCH SLIPS TO PERMIT RELATIVE RACK AND PINION MOVEMENT.