US2310403A

US2310403A - Cutoff device

Info

Publication number: US2310403A
Application number: US343203A
Authority: US
Inventors: Dice Charles
Original assignee: Pittsburgh Plate Glass Co
Current assignee: PPG Industries Inc
Priority date: 1940-06-29
Filing date: 1940-06-29
Publication date: 1943-02-09
Anticipated expiration: 1960-02-09

Description

C.'D|CE CUTOFF DEVICE Filed June 29, 1940 Sheets-Sheet-l CHARLES DICE.

Feb.9,1943. H E' 2, 10,403

, CUI'OFF DEVICE Filed June 29, 1940 2 Sheets-Sheet? CHARLES DNZE.

Patented Feb. 9, 1943 CUTOFF DEVICE Charles Dice, Mount Vernon, Ohio, assignor to Pittsburgh Plate Glass. Company, Allegheny County, Pa, a corporation of Pennsylvania Application June 29, 1940, Serial No. 343,203

8 Claims.

This invention relates to so-called cut-off devices for severing sheet glass during drawing operations, and it has particular relation to a structure which prevents scratching or marring of the glass in connection with the operation of severing devices.

One object of the invention is to provide an improved arrangement of cut-01f device which automatically operates to prevent portions of the device scratching or otherwise marring the glass.

Another object of the invention is to provide an improved control mechanism for influencing operation of clamping members in a glass cutoff unit.

Another object of the invention is to provide an improved mechanism which is automatically operable in response to movement of a cut-off unit during the operation of the latter to control operation of clamping members.

In severing drawn sheet glass, the latter is moved upwardly between rolls of conventional drawing apparatus and at a predetermined position, the glass is severed and removed from the apparatus in suitable measured sections. It is customary to sever the sheet glass by means of out-off units which are automatically clamped upon opposite sides of the glass and travel concurrently therewith while the cutting operation is in progress. At the completion of each cutting operation, the unit is automatically released from clamping relation and lowered to a starting position.

These cut-01f units must be flexible in order to conform to the movement of the glass without breaking or injuring it. However, certain disadvantages of scratching or otherwise marring the glass have been a characteristic of previously known types which, in their incidental movements, come in contact with the glass at times other than during the actual clamping operations. The principal feature of this invention involves the incorporation of a control mechanism in a cut-off unit which insures rapid and efficient operation of the unit without danger of scratching the glass. The control mechanism is automatic in its operation and responds to the normal operation of the unitwithout in any way interfering with the proper functioning thereof.

In the drawings:

Fig. 1 is a fragmentary end elevation of a cutoff device in its open or unclamped position as applied to a glass drawing apparatus shown in cross section"; Fig. 2 is a fragmentary'elevation similar to Fig. 1, in which the cut-off device is shown'in closed position; Fig. '3 is a fragmentary side elevation of the structure shown in Fig. 1; Fig. 4 is a horizontal section taken substantially along the line IVIV of Fig. 2; and Fig. '5 is a horizontal section, on a larger scale, taken substantially along the line VV of Fig.

In practicing the invention, a cut-off device ill for severing sheet glass l I is mounted in floating relation in connection with a conventional glass drawing apparatus 13 which includes drawing rolls [5 engageable upon opposite sides of the glass which travels in a substantially vertical plane along which the cut-off device is vertically'movable. The general type of cut-01f .device employed is exemplified in U. ,8. Patents Nos. 1,373,533 and 1,973,723, in which a cutting unit is automatically controlled at predetermined intervals for properly cutting the sheet glass as it travels upwardly.

The cut-off device Ill comprises an upper frame structure I 6 which includes conventional solenoid structure I! shown diagrammatically in Figs. '1 and 2. Each solenoid structure includes an upwardly movable core l8 having at its lower end a pair of horizontally slotted portions H3 in which the inner ends of oppositely disposed bell cranks 20 are pivotally connected, as indicated at 2|. Intermediate portions of the bell cranks are provided with pivotal supports '23 .upon .a lower portion of the solenoid supporting structure l1. These bell cranks extend outwardly in opposite directions and their outer ends are pivotally connected, as indicated at'25, to the innerends of links 26 which have oppositely extending outer ends pivotally connected, as indicated at '21, upon lower portions of suspended arms 30. Pivotal connections 3| in the frame structure 16 support the arms at their upper ends.

Clamping frames 33 having resistance elements 35 arranged horizontally thereon are secured horizontally along the lower portions of the arms 30. Adjacent opposite end portions .of the cut-off unit H! are suspended by means .of cables 38 which are connected to the upper frame structure It and are trained over pulleys 31 rotatably carried on conventional overhead supports 38 forming a part of the drawing apparatus structure. Free ends of the cablesare secured to counterbalancing weights39 whosecombined weights are less than the weight of the cut-off unit. However, the latter is sufficiently heavy to insure proper downward movement thereof until the arms 30 strike an upperplatform portion 50 of the drawing apparatus. This action is not sudden, but more or less in the form of a settling movement of the units.

Rollers 5| having bearing connections 52 on the lower ends of the arms facilitate movement of these arms in the closing or clamping action of the frames 33. Opposite sides of the solenoid supporting structure I! are provided with oppositely extending latches 53 having pivotal connections 55 securing them to such structure and these latches are notched to form thereon shoulders 56 and relatively narrow'fingers 57. The outer ends of the latches extend through slots 58 formed in the arms 30 and the fingers 51 normally rest upon the lower walls or extremities of the slots. The outer end of the latches constantly tend to move downwardly under the influence of gravity.

A latch actuating rod 60 is longitudinally slidable in a guide 6| formed coextensively and rigidly on each arm 30 and the lower end of this rod normally extends downwardly beyond the roller 5|. A head 63 rigidly secured to the upper end of each rod 60 has a slotted portion 65 which fits upon the arm 30 and is movable into engagement with the outer end of the latch 53. When the cut-off unit moves downwardly from the full line position to broken line position (Fig. 1), the lower ends of the rods 60 strike the apparatus platform 50 and are moved upwardly until the heads 63 strike the latches 53 and the arms 30 are then free to swing inwardly. This action occurs only in the lower position of the unit.

In the operation of the apparatus, the sheet glass II is movable upwardly and the cut-off unit is disposed in the position indicated in broken lines of Fig. 1. In the upward movement of the glass, the upper edge of the latter strikes an electric switch 61 which energizes the solenoid core I8 and causes the frames with the resistance elements thereon to be clamped upon opposite sides of the glass, as shown in broken'lines of Fig. 2. The switch is mounted upon a frame portion 68 of the glass drawing apparatus. Continued movement of the glass carries the counterweighted unit upwardly therewith until the resistance elements have rendered the glass severable along the line of engagement therewith. It is, of course, to be understood that the type of cutting element employed may be in the form of an electric resistance element or a conventional cutting tool, both of which are shown in the U. S. patents mentioned above.

Upon movement of the cut-off device upwardly a predetermined distance, it actuates a switch 69 and causes the solenoid to be de-energized. Then the arms 30 automatically swing outwardly away from the glass. The switch 69 is also mounted upon a frame portion 68 of the glass drawing apparatus. In order to prevent continued swinging 0r oscillation of the arms 30, the latches drop by gravity to such position that the latch shoulders 56 engage the arms when the latter reach their outwardly swung position shown in full lines of Fig. 1. They are held in this outwardly swung position until released by the rods 60. This action is automatic and as the cut-off device which has been freed from clamping relation drops automatically and relatively slowly by gravity, the section of glass severed can be removed. When the rods 60 strike the platform 59, they move upwardly and release the latches to present the apparatus in condition for the succeeding similar cycle of operation as described.

It is to be understood that the electric switches B1 and 69, together with the solenoid structure I1, are included in conventional electric circuits, the specific description of which is not necessary for practical application of the invention described above.

Although only one form of the invention has been shown and described in detail, it will be apparent to those skilled in the art that the invention is not so limited, but that various changes can be made therein without departing from the spirit of the invention or from the scope of the appended claims.

I claim:

1. In a cut-off unit for severing sheet glass, a pair of members movable inwardly toward and outwardly away from each other for clamping sheet glass therebetween, a support provided with means pivotally suspending each of said members thereon, locking mechanism mounted on the support and provided with means engagable with the members in response to outward movement of the latter for releasably locking the members in outwardly swung positions, and a device movably mounted on each member and engagable with the locking mechanism to release said members from their outwardly swung positions.

2. In a glass cut-off apparatus, a frame having counterweight mechanism for suspending it in vertically movable relation along a path of drawing of sheet glass, oppositely disposed depending arms pivotally suspended from the frame and swingable toward and away from the vertical plane of drawing of the sheet glass to clamp the latter, locking mechanism disposed adjacent said arms and movably supported on the frame, said locking mechanism and arms including engagable parts responsive to outward swinging movement of the arms for releasably locking the latter in outwardly swung positions.

3. In a glass cut-off apparatus, a frame having counterweight mechanism for suspending it in vertically movable relation along a path of drawing of sheet glass, oppositely disposed depending arms pivotally suspended from the frame and swingable toward and away from the vertical plane of drawing of the sheet glass to clamp the latter, locking mechanism engageable with said arms and movably supported on the frame, to lock said arms in outwardly swung positions, releasing means connected to said arms, said locking mechanism and releasing means including coacting parts relatively movable in response to vertical movement of said frame to release the arms from their outwardly locked positions.

4. In a vertically movable cut-off unit for severing sheet glass including apparatus for drawig sheet glass in a vertical plane, clamping members swingable toward and from the glass, means for mounting said members in swinging relation, locking mechanism disposed adjacent the clamping members and movably supported on said means, said locking mechanism and clamping members including engageable parts responsive to outward swinging movement of the clamping members for releasably locking the latter in outwardly swung positions, releasing means connected to said clamping members, said locking mechanism and releasing means including c'oacting parts relatively movable in response to downward movement of said unit to release the clamping members from their outwardly locked relation.

5. In a cut-01f unit for severing sheet glass, a frame movable between upper and lower positions, supporting structure carrying the frame in its upward and downward movement, a pair of member swingable inwardly toward and outwardly away from each other for clamping sheet glass between them, means for pivotally mounting said members upon said frame, locking mechanism mounted on the frame, said mechanism and members including coacting elements engageable in response to outward movement of the members for releasably locking the latter in outwardly disposed positions, and a device movably mounted on each member and engageable with the locking mechanism to release said members from their outwardly disposed positions.

6. In a cut-off unit for severing sheet glass, a frame movable between upper and lower positions, supporting structure carrying the frame in its upward and downward movement, a pair of members swingable inwardly toward and outwardly away from each other for clamping sheet glass between them, means for pivotally mounting said members upon said frame, locking mechanism mounted on the frame, said mechanism and members including coacting elements engageable in response to outward movement of the members for releasably locking the latter in outwardly disposed positions, downwardly disposed releasing means operatively connected to said members, and a stationary element arranged in operative relation with said releasing means and against which the latter strikes in response to movement of the frame to its lower position to release said mechanism from locked relation with said members.

'7. In a cut-off unit for severing sheet glass, a frame movable between upper and lower positions, supporting structure carrying the frame in its upward and downward movement, a pair of members swingable inwardly toward and outwardly away from each other for clamping sheet glass between them, means for pivotally mounting said members upon said frame, locking mechanism mounted on the frame, said mechanism and members including coacting elements engageable in response to outward movement of the members for releasably locking the latter in outwardly disposed positions, a stationary part disposed below the frame and limiting downward movement thereof, and a device slidable on each of said members and extending below the lower extremity thereof and movable downwardly with the frame into engagement with the stationary part to actuate the locking mechanism out of locked relation with the members.

8. In a glass cut-off unit for severing sheet glass, a frame movable between upper and lower positions, supporting structure carrying the frame in its upward and downward movement, a pair of members swingable inwardly toward and outwardly away from each other for clamping sheet glass between them, means for pivotally mounting said members upon said frame, looking mechanism mounted on the frame, said mechanism and members including coacting elements engageable in response to outward movement of the members for releasably locking the latter in outwardly disposed positions, a stationary part disposed below the frame and limiting downward movement thereof, a device slidable on each of said members and extending below the lower extremity thereof and movable downwardly with the frame into engagement with the stationary part to actuate the locking mechanism out of locking relation with the members, and rollers on the lower portions of the members adapted to rest on said stationary part while the frame is in its lower position.

CHARLES DICE.