US2055711A - Glass feed control mechanism - Google Patents

Description

Sept. 29, 1936.

S. G. STUCKEY GLASS FEED CONTROL MECHANISM s Sheets- Sheet 1 Filed June '7, 1935 Sept. 29,1936. G KE 2,055,711

GLASS FEED CONTROL MECHANISM Filed June 7, 1933 5 Sheets-Shet 2 'l I II I I I I ll Sept. 29, 1936. s STUCKEY 2,055,711

GLASS FEED CONTROL MECHANISM Filed June 7, 1935 5 Sheets-Sheet 3 Patented Sept. 29, 1936 UNITED STATES PATENT OFFIE GLASS FEED CONTROL MECHANISM Application June 7, 1933, Serial No. 674,709

18 Claims.

This invention relates to improved apparatus for controlling the feed of molten glass, and more particularly to that type of apparatus commonly known and referred to as air feeders.

An object of this invention is to provide improved apparatus which is simple in construction, durable in operation, easy of adjustment and control, which will efficiently regulate the weight and shape of gobs of molten glass fed from a forehearth to a forming machine.

Another object of this invention is to provide, in apparatus of the character described, a pump, for the introduction of air into a control chamber, which will be positively driven on its compression stroke and variably driven on its suction stroke.

Another object of the invention is to provide, in apparatus of the character described, a pump for a control chamber having positively driven means for its compression stroke with means for limiting the length of the stroke in one direction, that is to say, an air piston pump movable in one direction to a fixed position and in the opposite direction to a variable position.

Another object of the invention is to provide, in apparatus of the character described, a control pump positively driven, with means associated with the driving device to open the system to atmosphere, at one or two points in the cycle of opera- 3 tion, and to provide means for adjusting the device to vent the system at different points in the cycle of operation.

Another object of the invention is to provide, in a pump of the character described, having means for positively driving it on the compression stroke, adjustable apparatus whereby the suction stroke of the pump can be varied both as regards the speed and the length of the stroke.

Another object of the invention is to provide, in a pump of the character described, a single exhaust valve operable to vent the system 01 atmosphere at or near the end of both the compression stroke and the suction stroke, or either without the other.

In feeding molten glass, by means of an air controlled chamber positioned above an outlet orifice in a forehearth, it is essential for the control of weight and shape that the compression stroke of the pump be uniform. In the use of air driven pumps difficulty is sometimes encountered in a tendency of the piston to lag or vary in its speed during the compression stroke. This results sometimes from improper lubrication and also from accumulation of rust and foul oil. In other cases it may be due to moisture in the pump cylinder. If the atmosphere contains a great deal of moisture and this moisture is drawn into the pump cylinder and condenses, the hot air arising from the surface of the glass in the control tube overheats the moisture and results in building up 5 a false pressure in the system. By the present invention these difiiculties are eliminated by providing a pump which is positively cam driven on its compression stroke and with means for venting the pump cylinder to atmosphere during each 10 cycle of operation.

This invention provides a pump which is driven by an air motor for the suction stroke, in order that the speed of that stroke may be adjustably varied even during the operation. This system also permits simple means to be employed for varying the length of the stroke by adjustments which may be made readily and during the operation of the device.

Other and further objects will be apparent from the following detail description taken in connection with the accompanying drawings, in which- Fig. 1 is a plan View of the device.

Fig. 2 is an elevation partly in section. 25

Fig. 3 is a top plan view of the operating lever.

Fig. 4-. is an elevation of the lever shown in Fig. 2 with the parts which are carried thereon.

In accordance with this invention, an air controlled tube or chamber I is positioned vertically in a iorehearth 2 above an outlet orifice 3. The use and operation of such an arrangement is well understood in the art and in general use. It is to be understood that by periodically varying the pressure within the tube l the shape and weight of an extruded gob A of molten glass may be controlled. It will also be understood that shears 4 are so constructed and arranged in synchronism with control mechanism that they will sever the suspended gob A at the proper point in the cycle of operation in connection with the Varying pressures in the tube I.

A bed plate 5 is secured to the forehearth and supports the apparatus, in accordance with this invention, which is adapted to affect pressure conditions within the tube l. The cylinder 6 is supported on posts I which are in turn supported by the bed plate 5. The cylinder 6 communicates by a conduit 8 with the tube I. A piston 9 is adapted to be reciprocated in the cylinder 6 and thereby supplies super-atmospheric pressure and sub-atmospheric pressure through the conduit 8 to the tube l. The piston 9 is reciprocated by a connecting rod it] connected to a lever H. The

lever I is pivotally supported at its outer end by a bracket I2 carried by the bed plate 5.

The lever II is cam driven on its upward or compression stroke and carries a roller I3 mounted on a stud shaft I4. The roller I3 is adapted to engage and ride a cam I5 secured to and rotated by a shaft I5. It will be understood that the shaft I6 will be rotated in the direction of the arrow shown in Fig. 2, by any suitable mechanism', at a constant but adjustable speed and at such a speed as will cause the shaft to rotate once for each gob to be severed. A typical speed is 20 R. P. M.

It will now be observed that by rotating the shaft I6 the lever I I will be lifted and the pump positively driven on its compression stroke, once for each rotation of the shaft I5. It may now be further explained that proper connections may be made either by the device specificallyillustrated herein and which will later be described in detail, or by other means which are well known in the art, in order that the shears 4 will be operated in synchronism with the rotation of the shaft I6, or the rotation of the lever II, and thus, at the proper time during each cycle of operation, a gob A will be severed, shortly after the end of the compression stroke of the piston 9, by the shears 4. The return or suction stroke of the piston 9 may be induced by a spring or weight and a dash pot or by a compressed air motor, as specifically shown in the drawings. In the embodiment specifically shown the compressed air motor includes a cylinder 20, supported by the bed plate 5, and a crosshead or piston 2| with a piston rod 22 connected at its upper end with the outer end of the lever II. Compressed air is introduced into the cylinder 25 through a conduit 23 and controlled by a valve 24, actuated by a cam 25, which cam is secured to and rotated by the shaft I6.

The cylinder 20 is closed at its lower end by a head 26 which carries a spring pressed poppet valve 21. The poppet valve Z'I has a port 28 extending downwardly and forming a seat for an adjustable needle valve 29. It will thus be observed that the cylinder 25 and piston 2| form a dash pot and it will be obvious that means other than those shown may be utilized with this dash pot to actuate the lever I I on its downward or suction stroke. I prefer, however, to drive the piston 2| by compressed air as indicated and as controlled by the valve 24.

The particular construction of the valve 24 is not of importance but, as specifically illustrated, it includes a chamber communicating with a source of compressed air supply 3|. A slide valve or member 32 is adapted to reciprocate in the chamber 35 and is actuated by a rocker arm 33, which carries a roller 34, arranged and adapted to contact the cam 25. The slide valve 32 has a central bore 35 communicating with a cross bore 36, whereby a port 37, which is in communication with the conduit 23, may be opened to the supply conduit 3| when the valve is moved to open position. When the valve is moved to exhaust position, the port S'l communicates with an exhaust port 38 through an annular space 39 on the slide member 32.

A post 40 is secured to the bed plate 5 and is positioned in the plane of the lever I I. A sleeve 4| is in threaded engagement with the post 40 and is thereby adjustable as to height. The arrangement is such that the lever II on its down stroke strikes the top of the sleeve 4| and its downward movement is thereby limited. The

:length of the stroke of the lever Il may be adjusted by changing the elevation of the sleeve 4|. A lock nut 42 serves the function of locking the sleeve in any selected position.

A bracket 43 is secured to the lever II and carries a valve casing 44 which thereby oscillates with the lever II. A poppet valve 45 is positioned and seated in the valve body and has its stem extended and adapted to be moved by a rocker arm 46. The valve body 44 communicates by a flexible conduit 47 with the interior of the cylinder. The arrangement is such, as will presently be described, that the valve 45 will be lifted off its seat and the cylinder 6 thereby opened to atmosphere at the end of each stroke.

The means for opening the valve 45 at the end of the compression stroke comprises a screw 48 threaded in an abutment on the cylinder 6 and in the path of the outer end of the rocker arm 46. A lock nut 49 is provided for the screw 43 whereby the screw may be locked in any selected position.

The means for opening the valve 45 at or near the end of the suction stroke includes a nut 50, in threaded engagement with the sleeve 4|, and a pin 5| mounted in a guideway on the lever II. The arrangement is such that the lower end of the pin 5| is adapted to engage the edge of the nut 59 and the upper end of the pin is adapted to engage the inner end of the rocker arm 46. It will thus be seen that when the lever II is oscillated to its lowermost position, the pin 5| will strike the nut 55, pushing the pin upwardly, thus opening the valve 45. A lock nut 52 is in threaded engagement with the sleeve 4| and is adapted to lock the abutment nut in any selected position.

It will now be obvious that the screw 48 and the nut 5|] may be so adjusted in position as to cause the valve 45 to be opened at any selected point near the ends of the compression and suction strokes, respectively, and the cylinder 6 may thereby be opened to atmosphere. It will also be obvious that the screw 48 and the nut 50, either or both, may be so adjusted as to be wholly ineffective to open the valve 45. The arrangement of the screw 48 and the nut 5|! is such that these adjustments may be made while the machine is in operation, as will appear obvious from the drawings and the preceding description.

A valve is provided for operating the shears 4 and is adapted to be actuated by the lever II at a point in the cycle when the piston 9 is at or near the end of its compression stroke. This valve includes a valve housing 6|, carried by a valve support 62, secured to the upper end of the bracket I2. A poppet valve 63 is seated in the housing and has an extended stem with its end positioned within the path of a striking surface 64 on the lever II. A conduit 65 leads into the valve housing from any convenient source of compressed air supply, and a control conduit 66 leads from the discharge side of the valve and is intended to be connected with suitable mechanism for operating the shears 4, which may be constructed after a manner which is well understood in the art.

Valve mechanism for tripping a forming machine, used in connection with the feeder, is also provided and adapted to be tripped incident to the movement of the lever II. Such a valve includes a housing 61 supported by the bed plate 5. A poppet valve 68 seated in the housing has an extended stem adapted to be engaged by a lever 69. The upper end of the lever 69 is adapted to be engaged by mechanism, which will presently be described, carried by the lever II. The lower end of the lever 69 is extended forming'a handle III, with which to manually trip the forming machine when the feeder is idle or at other times as desired by the operator.

The means carried by the lever I I for tripping the valve lever 69 include a sliding plate II slidably mounted on the lever II in suitable guides. The lower end of the slide 'lI carries a valve tripper dog 12 rotatably mounted on a pin 13 and held by a spring 14 against a stud I5 in normal position.

The slide II is pivotally connected to one end of a lever 16, which lever is pivotally supported by a pin H on the lever I I. The lever II carries a support 78, which in turn carries an adjustable Wheel 19, threaded to receive a screw 80. The lower end of the screw 80 is connected to one end of the lever I6 by a pin 8|.

It will be seen, therefore, that by turning the wheel 19 the position of the dog 12 may be adjusted and the operator may thereby determine the point in the cycle at which the valve 68 is to be tripped.

The operation of the device will be fairly apparent from the foregoing description. Nevertheless, a further description of the operation of the device may assist in understanding the invention. The cam shaft I6 will be rotated by any convenient source of power in a direction indicated by the arrow (Fig. 1). The rotation of the cam shaft IE will cause a rotation of the cam I5, which engages the roller I3 on the lever I I, thus lifting the lever and moving the piston 9 on its compression stroke. The result will be that air under pressure will be forced into the control tube I, which in turn will force the molten glass downwardly and out through the orifice 3. Since the pump is positively driven by the cam I5 the recurring impulses within the control tube I will always be the same, except as changed by the regulating devices herein described.

The amount of pressure brought to bear upon the surface of the glass is governed by the speed of the stroke and by the length of the stroke. The speed of the stroke, of course, can be changed by changing the cam I5 or by increasing the speed of the cam shaft I6. The length of the stroke can be adjusted readily, even while the feeder is in operation, by adjusting the position of the sleeve II on the post 40. It is to be understood, as previously described, that the top of the sleeve 4| engages the bottom of the lever II and thus limits the extremity of the down stroke of the piston.

When the lever I I has approached near the end of its upward stroke, the end of the screw 48 will strike the rocker arm 46, thus tripping the valve 45 and opening the cylinder 6, and thereby the tube I, to atmosphere. The exact point at which the valve "55 will be tripped may be regulated by adjusting the position of the screw 48. By opening the cylinder 5 to atmosphere at the end of the stroke the pressure in the system is reduced to atmosphere, thus preventing a quicker action on the suction stroke and also rids the system of any foreign matter, especially moisture which may be drawn into the control chamber.

Near the upper limit of the movement of the lever II on the compression stroke, which will be at the completion of the formation of the mold charge, the valve 63 will be tripped by the upward movement of the lever II and, by mechanism not shown, the shears 4 will be caused to sever the mold charge. The closing movement of the shears 4 is regulated so that there is a lag between the action of the valve 63 and the shears 4, this lag occurring as an incident to the operation of shears as they are usually constructed. Thus, the suction stroke is commenced before the shears are closed and this is desirable because the suction will lift the stub of glass above the shears and prevent overheating the shear blades.

The cam 25, mounted on the cam shaft I6, is so arranged as to open the valve 32 at the completion of the compression stroke, thus placing in operation the air motor, comprising the cylinder 20 and the piston 2 I. It is to be understood that during the compression stroke the valve 32 is open in such a position as to open the cylinder 20 to atmosphere through the port 38. The air motor moves the lever I I in a downward position for the suction stroke to a position in which the lever I I strikes the top of the sleeve ll.

During the suction stroke the valve 68 is tripped by the dog 52, moving with the lever II, and the forming machine, not shown but operated in conjunction with the feeder, is tripped. At or near the end of the suction stroke the bottom of the pin 5| strikes the nut 5d again opening the piston B to atmosphere.

During the compression stroke the valve 21 in the cylinder 28 opens under a slight reduction in pressure, permitting the air to freely flow into the cylinder. On the reverse stroke, that is when the piston 25 is moving downward, the cylinder 20 acts as a dash pot and can be regulated readily by the needle valve 29.

It will be obvious that parts of the invention may be used without the whole, that the invention may be employed with additions thereto, and that various changes may be made in the details of construction, within the scope of the appended claims, without departing from the spirit of this invention.

I claim:

1. In a glass feeder, an air pump having a piston, a lever for reciprocating the piston, a cam adapted to move the lever for the compression stroke of the piston, separate means for moving the piston for the suction stroke, and means to limit the extremity of movement of the piston on the suction stroke.

2. In a glass feeder, an air pump having a piston, a lever connected to the piston, a cam adapted to move the lever for the compression stroke of the pump, separate means for moving the lever for the suction stroke, and an adjustable abutment adapted to contact the lever and limit the extremity of its movement on the suction stroke.

3. In a glass feeder, an air pump having a piston, a lever connected to the piston, a rotating cam adapted to contact and move the lever, separate means for returning the lever on a reverse stroke, and means variable at will for limiting the extremity of such reverse stroke.

a. In a glass feeder, an air pump having a cylinder and piston, a lever connected to the piston, a cam adapted to move the lever, a valve mounted on and carried by the lever, a flexible conduit connected between the cylinder and valve and adapted to be opened to atmosphere by the valve, and means for opening the valve upon contact with a stationary abutment when the lever is reciprocated.

5. In a glass feeder, an air pump having a cylinder and piston, a lever connected to the piston, a cam adapted to move the lever, a valve mounted on and carried by the lever, a flexible conduit connected between the cylinder and valve and adapted to be opened to atmosphere by the valve, means carried by the lever and adapted by pressure thereon to open the valve, a stationary member positioned to contact said means near the end of the compression stroke of the piston, and means operable at will for adjusting the position of said member.

6. In a glass feeder, an air pump having a cylinder and a piston, a lever connected to the piston, a cam adapted to move the lever, a valve mounted on and carried by the lever, a flexible conduit between the cylinder and valve and adapted to be opened to atmosphere by the valve, means carried by the lever and adapted by pressure thereon to open the valve, a stationary member positioned to contact said means near the end of the suction stroke of the piston, and means operable at will for adjusting the position of said member.

'7. In a glass feeder, an air pump having a cylinder and piston, a lever connected to the piston, means for reciprocating the lever, a valve mounted on and carried by the lever, a flexible conduit connected between the cylinder and valve and adapted to be opened to atmosphere by the valve, means carried by the lever and adapted by the pressure thereon to open the valve, a stationary member positioned to contact said means near the end of the compression stroke of the piston, means operable at will for adjusting the position of said member, a stationary member positioned to contact said means near the end of the suction stroke of the piston, and means operable at will for adjusting the position of said last named member.

8. In a glass feeder, an air pump having a cylinder and piston, a lever connected to the piston, means for reciprocating the lever, a valve mounted on and carried by the lever, a flexible conduit connected between the cylinder and valve and adapted to be opened to atmosphere by the valve, a rocker arm carried by the lever and adapted to open the valve, and a stationary member positioned to contact said means near the end of the compression stroke of the piston.

9. In a glass feeder, an air pump having a cylinder and piston, a lever connected to the piston, means for reciprocating the lever, a valve mounted on and carried by the lever, a flexible conduit connected between the cylinder and valve and adapted to be opened to atmosphere by the valve, a sliding pin carried by the lever and adapted to open the valve, and a stationary member positioned to contact said pin near the end of the suction stroke of the piston.

10. In a glass feeder, an air pump having a cylinder and piston, a lever connected to the piston, means for reciprocating the lever, a valve mounted on and carried by the lever, a flexible conduit connected between the cylinder and valve and adapted to be opened to atmosphere by the valve, a rocker arm carried by the lever and adapted to open the valve, a stationary member positioned to contact said rocker arm near the end of the compression stroke of the piston, a sliding pin carried by the lever and adapted to open the valve, and a stationary member positioned to contact said pin near the end of the suction stroke of the piston.

11. In a glass feeder, an air pump having a piston, a lever connected to the piston, a cam adapted to move the lever, a valve secured to a stationary support and adapted to operate associated mechanism, means carried by the support and adapted to open the valve, a member pivoted to the lever and adapted when reciprocated by the lever to operate said means, and means operable at will to move said member on its pivot to adjust the position of said member.

12. In a glass feeder, an air pump having a piston, a lever connected to the piston, a cam shaft, a cam carried by the shaft and adapted to move the lever for the compression stroke of the pump, a compressed air motor connected to the lever and adapted to move the lever for the suction stroke of the pump, a control valve for the motor, and a cam carried by said shaft and adapted to operate said valve.

13. In a glass feeder, an air pump having a piston, a lever connected to the piston, a cam adapted to move the lever for the compression stroke of the pump, separate means for moving the lever for the suction stroke, means forming a dash pot connecting with the lever, and an adjustable valve in the dash pct.

14. In a glass feeder, an air pump having a piston, a lever for reciprocating the piston, a shaft, mechanical connections between the shaft and the lever whereby rotation of the shaft will movethe lever for the compression stroke of the piston, separate means for moving the piston for the suction stroke, and means independent of the shaft for regulating the speed of the piston on the suction stroke.

15. In a glass feeder, an air pump having a piston, a lever for reciprocating the piston, a driving shaft, a rotating cam on the shaft adapted to move the lever for the compression stroke of the piston, separate means for moving the piston for the suction stroke, and means independent of the shaft for regulating the speed of the piston for the suction stroke.

16. In a glass feeder, an air pump having a piston, a lever for reciprocating the piston, a rotating shaft, mechanical connections between the shaft and the lever for moving the lever on the compression stroke of the piston, a compressed air motor for moving the piston for the suction stroke, and means independent of the shaft for regulating the speed of the motor.

17. In a glass feeder, an air pump having a piston, a lever connected to the piston, a rotating shaft, mechanical connections between the shaft and the lever for operating the lever on the compression stroke of the piston, yielding means for returning the lever, means forming a dash pot connected with the lever, and a regulating valve for the dash pot.

18. In a glass feeder, an air pump having a piston, a lever connected to the piston, a rotating shaft, mechanical connections between the shaft and the lever for moving the lever on the compression stroke of the pump, a dash pot connected with the lever, an adjusting valve in the dash pot, and yielding means for moving the lever in opposition to the resistance of the dash pot.

SAMUEL G. STUCKEY.

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