US1671718A

US1671718A - Sheet-surfacing apparatus

Info

Publication number: US1671718A
Application number: US191577A
Authority: US
Inventors: Alfred L Harrington
Original assignee: Pittsburgh Plate Glass Co
Current assignee: PPG Industries Inc
Priority date: 1927-05-16
Filing date: 1927-05-16
Publication date: 1928-05-29
Anticipated expiration: 1945-05-29

Description

A. L. HARRINGTON SHEET SURFACING APPARATUS May 29, 1928. 7 1,671,718

Filed May 16, 1927 9 Sheets-Sheet '1' w $5 l I N m N N INVENTOR 9 Sheets-Sheet 2 A. L. HARRINGTON SHEET SURFAGING APPARATUS May 29, 1928.

@Ml i May 29, 1928.

. A. L. HARRINGTON SHEET SURFACING APPARATUS Filed May 16, 1927 9 Shefls-Sheet s 1. 7 o 3 12 65 2 W mm .22 7 "wa 1% 7 1 w 1 j 3 F 7 4 a 3 Q 1 34 4 99 7 1 1 m 1 a. A

inf/amen v I. H l

A. L. HARRINGTON SHEET SURFAC ING APPARATUS May 29, 1928.

9 Sheets-Sheet 4 Filed May 16, 1927 INVENTOR A. L. HARRINGTON SHEET SURFACING APPARATUS May 29, 1928.

9 Sheets-Sheet 5 Filed May 16, 1927 m Fra .7

I I l i I I I I l .J

May 29, 1928. 1,671,718 I A. L. HARRINGTON SHEET suamcme APPARATUS Filed May 16, 1927 9 Sheets-Sheet 6 I 1 F4' .5 165 J 174 May 29, 1928. 1,671,718 I A. L. HARRINGTON 1 SHEET SURFAC INC1 APPARATUS Filed May 16, 1927 9 Sheets-Sheet 7 I 165 1 l l i 2 I I l I 1* l 1 I i I i 1 I 1 L 1' J INVENTOR 9 Sheets-Sheet 8 Filed May 16, 1927 .ZJQ,

A. L. HARRINGTON SHEET SURFACING APPARATUS May 29, 1928.

May 29, 1928.

A. L. HARRINGTON SHEET SURFACING APPARATUS Filed May 16, 1927 9 Sheets-Sheet 9 m T N I V m Patented May 29, 1928.

UNITED STATES 1,671,718 PATENT OFI-lCE..

ALFRED Ii. HARRINGTON, OI CARNEGIE, PHNSYLVAIIA, AISIGIOB IO PLATE GLASS COMPANY, A. CORPORATION 01' PENNSYLVANIA.

snnrr-sonmcme arrm'rus Application me m 10, it. lerlal Io. 101m.

The invention relates to sheet surfacing machines and particularly to those for use. in surfacin sheet glass in a straight away or straight line operation, in which the glass sheets upon a train of tables or cars are passed beneath a series of grinding and pol- 1Shi1'1 machines. In such an operation, there may e a series of 24 or more grinding machines followed b 48 or more olishing machines, and it is t e object of tlie present invention to provide improved means for controlling the operation of these machines, the raising and lowering movements of the runners and the operation of the drive of the cars or tables, so that, (1) the danger of breakage of the glass u on the tables is reduced to a minimum; 2) the starting and stopping of the'a' paratus is facilitated and loss of time avoi ed; (3) the load upon the electrical circuits is properly distributed; (43 and the safety of the apparatus is increase Certain embodiments of the invention are illustrated in the accompanying drawings, wherein:

Figure 1 is a plan view of the apparatus, a small number only of the individual inding and polishing machines being s own. Fig. 2 is a longitudinal section on the line II-II of Fig. 1. Fig. 3 is a section on the so line IIIIII of Fig. 1 on an enlarged scale. Fig. 4 is a section on an enlarged scale through the casing of the air valve and its magnetic control. Figs. 5 5 and 5 together show the wiring diagram of the system. Fig. 6 is a detail of one of the runner supporting levers and the switches operated thereby. Figs. 7, 8, 9, 10 and 11 are enlarged views of different parts of the apparatus shown in Figs. 5, 5 and 5", such 'views being diagrammatic in character. And Fig. 12 shows a modification, involving a different prime mover for raising the runner, and the wiring diagram therefor.

Referring to Figs. 1, 2 and 3, A, B, C, D, E and F are a plurality of surfacin machines arranged in series above the trac 1, the machines A and B bein grinding machines, and C, D, E and 15 polishing machines. As a matter of fact, each machine represents a group of about 12 machines, it being impracticable to illustrate such a large number of units and their wiring diagrams, as will be apparent later when Figs. 5, 5 and 5 are consi ered. It will be understood that all the machines of each group have the same wiring control and 0 rate simultaneously, so that a consideration of a representative machine of each group will make clear the entire arrangement.

Mounted on the track 1 are a series of tables 2, 2,2, etc. placed end to end in abutting relation and provided on their lower sides with the racks 3, by. means of which the tables are fed continuously forward from left to ri ht (Fig. 2 tables being supplied at the le t hand on of the system as they are removed from the right hand end thereof. The glass sheets to be surfaced are embedded in plaster upon the tops of the tables so that the series of cars constitute in effect a continuous grinding table. The racks are driven by two spur wheels 4, 4 at the left hand end of the track, such gears belng lin turn operated from the motors G and through the spur gears 5, 5 and suit able reduction gearing in the

casing

6, 6. Either motor is suflicient to move the tables forward, the use of the two being merely a matter of precaution to take care of an emergenc which might arise due to the failure 0 a single drive motor.

At the end of the track toward which the cars are moving (Fig. 2)l is a friction brake comprising a shaft 4" aving a .pinion' in engagement with the racks 3, a wheel 4" keyed to the shaft, and a brake band 4 passing around the wheel. This device provides a yielding resistance retarding the movement of the tables so that any danger of the tables becoming separated is avoided and the rate of their movement beneath the surfacing machines is made more even and uniform.

The construction of one of the surfacing units, preferably employed, will be seen by reference to Fig. 3, which shows the first grinding machine A of the series. The movable parts are supported upon a framework 7, which carries the casting 8. Al tubular casing 9 carries the runner shaft 10, which in turn'supports the runner 11. The casing, and with it the runner shaft and runner, are guided for vertical movement by the lever 12 and the arm 13 pivoted upon the

ins

14 and 15 mounted in the casting 8. he lever and arm engage the

trunnions

16 and 17 on the casing 9, the lever 12 serving to support such casing and move it up and down, as later described. A motor A is supported on the up er end of the casin 9 and serves to drive t e runner shaft 10 tl rough the intermediary of suitable reduction gearing in the

casings

18 and 19.

The lever 12 carries at its outer end the yoke 20, in which is guided for vertical movement the block 21, through which extends a rod 22 threaded at its lower end and carrying the adjusting hand wheel 23. The lower end of the yoke 20 supports the base of the coil spring 24, so that when the rod 22 is moved downward, moving the block 21 downward, the spring is compressed, thus tending to counterbalance the wei ht of the grinding unit on the other end 0 the lever 12. The wheel 23, which is threaded on the rod 22, is held against upward movement by means of a sleeve 25 ivoted in brackets 26 secured to the lower anges of one of the frame members. The hand wheel 23, in connection with the rod 22 and sprin 24 thus serve as a means of counterweig ting the grinding unit to any desired extent de ending upon the grinding conditions, an also serves as a means for lifting the runner entirely out of contact with the glass when this becomes necessary.

Mounted above the lever 12 of each of the grinding and polishing machines is an air lift for the grinding unit carried by the lever. This lift consists in each case of a c linder 27 secured to the framework of t e machine, together with a suitable piston in the cylinder provided with a piston rod 28 pivoted at its lower end to a bracket clamped to the lever arm. Alongside each piston is an air storage cylinder 29 having

pipe connections

30 and 31 leadin to the up or end of the cylinder 27 via t e valve casin 32, the flow from which c linder is electrically controlled, as hereina ter more fully explained. The storage cylinders are supplied with air under pressure from an air line 33 extending longitudinally of the series of grinding mac ines and provided with outlet branches 34 leading to the various storage cylinders. Provision of a storage cylinder adjacent each of the lifts insures a suflicient quantity of air to operate the cylinders promptly and in unison.

The electrically controlled valve mechanism in the casing 32 will be seen by reference to Fig. 4. A magnet winding I is provided in fixed position in the casing, adapted, when energized, to cause the downward movement of the tubular armature 35 slidably mounted in the upper end of the This armature en ages at its lower end a rod 36 slidably guifed in a sleeve 37, which acts as the core to the winding I. Mounted in the lower end of this rod 36 is a valve stem 38 carrying the

valves

39 and 40, the valve 39 being normally held closed the valve 40 open by means of the coil spring 41 located beneath the valve. 39.

of its piston 1s vented to the atmosp When the valve is in this position, the chamber of the cylinder 27 on the up er side ere via the pi e 31, the passage 42 and t e outlet 43. when current is supplied through the magnet winding I, the downward movement of the armature 35 causes the valve 40 to close and the valve 39 to open. This closes the outlet from the cylinder 27 through the passage 43 and admits a sup ly of air from the storage cylinder 29 via t 1e pipe 30, the assage 42, and the ipe 31. he up and own movement of t e arm 12 also opens and closes a pair of other switches 1- and a in the casin 43, whose functions are set forth later erein in connection with the description of the wiring dia ram.

Fi 5, 5 and 5 of the rawing shows the e ectrical apparatus for the system. The complete wiring diagram of only two of the mac ines is shown, but the arrangement of all the others will be readily apparent from a consideration of the two. The two selected are the first and third of the series; viz., A and C. It will be further understood that these two machines are representative of two groups of machines, each consisting of about 12 or more machines. The wiring for all the members of each grou is a duplication of that of the individual machine of the group, as illustrated and described.

The startin and stopping of the entire system, inclu ing the motors which drive t e tables and those for driving all the run ners is controlled from the panel J. This panel includes the start button K, the stop utton L, the multiple switch M, and the thermo-relay switch N, which 0 ens when the flow of current through eit er of the heating coils N N increases beyond a certain point. A part of this panel is shown on an enlarged scale in Fi 7. As here shown, the parts of the switc M are yieldingly held in the osition shown by the spring 44, thus holding the switch arms 45 to 49, which are attached tothe solenoid bar open, and the arm 50 closed. When current is passed through the coil 52, the bar is pulled to the left closing the switches 45 to 49 and openin the switch 50. As hereinafter more ful y described, the pressing down of the push button K causes current to pass through the coil 52, thus moving the time and insures that the runners shall be rotating and the tables movin therebeneath before the runners enga e the glass. The

arms

53, 53 of the switc i N are yieldingly held closed by the

bi-metallic strips

54, 54 fixed at their outer ends, such strips being located adjacent the heating coils N, N. The

arms

53, 53 lie in the same circuit as the coil 52 and are proi'ided with s rings 55, 55 tending to open them. When t e current through the heating'coils rises above a predetermined point, the heat from the coils causes the

arms

54, 54 to bend or warp, re: leasing the ends of the

arms

53, 53 so that they open, thus interrupting the flow of current through the arms and through the coil 52 so that the switch M opens, interrupting the operation of the entire system -Thermo-relays of this type are well known in the art so that no detailed showing or explanation is necessary.

he sequence control panel 0 includes the multiple switch P, the series of time relays A, B C, D E and F one for each group of runner motors, and a series of relays A", B C D E and F The time relay A and the relay A together control the operation of the motor A of grinding machine A, (Fig. 5*) or if A is a. group of 12 or more grinding machines, then the relays A and A control all the members of the group. Similarly, the relays C and C control the operation of the motor or group of motors G, as shown in Fig. 5.

The multiple switch P (Fig. 8) is similar to the switch M above described. It comprises a solenoid bar 60, operating the switch arms 61 to 66 and yieldingly pulled to the right by the spring 68. The bar is moved to the left to close the arms by the coil 69. The coil 69 is operated by alternating current from the transformer coil 212. This circuit, including the coil 69, passes through the arm 49 of the switch M, so that the energizing of the coil 69 and the closing of the switch arms 61 to 66 is dependent upon the closing of the switch M, which, as above explained, occurs only after the start button K is pushed down. It follows that the actuation of the time relays A to F and the starting of the runner motors A to F must be preceded by the closing of the multiple switch P, all of which appears in detail after the following brief discussion of the remainder of the control apparatus.

The six time relays which are closed after, and due to the closing of the multi 1e switch P, are all similar to the relay shown in Fig. 9. This relay comprises the arm 70 pivoted at 71 and having the contact ends 72 and 73 adapted to engage the

contacts

74 and 75 when the arm swings to the right, the solenoid bar 76 connected to the arm 70 bythe spring 77, the coil 78 for pulling current is supplied to themotor and to the coil 78 before the arm 70 closes, is regulated by the position of the arm 83, which can be held in any osition of circumferential adjustment by t 1e thumb screw 86 or any other suitable means. When current is supplied through the wire 87, it passes through the coil 78 to the return wire 88.- It may be here interpolated to avoid confusion that the

wires

87 and 88 are in the alternating current circuit, including the winding 69 and that the wire 88 also carries direct current. The current through 87 divides at the point 89 and passes through the circuit 90 to the motor and back to 87 at the point 91, via the contact 92, which engages the arm 93 pivoted at such point 91. The coil 78 and motor are thus energized when current flows through 87, and the disc 81 with the arm 83 begins to rotate. When the time elapses for which the relay is set, thearm 83 engages and trips the latch.84, and the spring 77 placed under tension by the solenoid bar 76, pulls the arm 70 to the right so that the contact ends 72 and 73 engage the contacts 7 4 and 75, thus establishing acircuit between the

wires

88 and 94, the wire 88, as above stated, being the lead-in wire carrying direct current. The wire 94 leads to the relay A (Fig. 11) and serves to close this relay, as later described, so as to cause the actuation of the starter of the motor A. The movement of the arm 70 to the right breaks the circuit between 92 and 93, so that the operation of the motor 80 is stopped after the arm 70 is moved to closed position. When the circuit between 87 and 88 is broken, the spring 79 will move the parts back to the position shown, the arm being engaged and locked in open position by the latch 84. When the circuit through the coil 78 is interrupted, automatic means, not shown, move the worm 82 out of engagement with the worm wheel 81, and a spring returns this wheel and the arm 83 to starting position, as shown. This time relay is standard equipment, known in the art, and, therefore, not illustrated in all its details.

The closing of the relay A as just described, controls the operation of the relay A, such relay closing so that direct current is permitted to flow through the relay and to the starter of the motor A. This relay A will be understood by referenceto Fig. 11, wherein 94 is the inlet wire from the relay A (Fig. 9) above referred to and 95 is the return wire throu h which the current flows back to the negative side of the DC generator after passing through the coil 96. This causes the contact arms 97 and 98 ivoted at 99 and 100 and connected to the so enoid bar 101 to swing to the left against the tension of the spring 102, engaging the

contacts

103 and 104. This com letes a circuit from the line 88 through t e arm 97, contact 103, line 105 and coil 106 back to the line 95, so that the contact arm 107 is swung to the left against the tension of the spring 108 by the solenoid bar 109, causing the arm to engage the contact 110. This completes a circuit from the positive line 88 to the line 111, which supplies current to the starter of the motor A and causes the operation of such starter, as later described. The movement of the arm 98 to the left also breaks the contact between such arm and the contact 112 at the terminal of the line 113, so that current to such line which had up till this time been supplied from the line 88 is cut oil'. The line 113 also leads to the control apparatus of the motor and functions in connection therewith, as later described.

The starting panel S for the motor A is controlled from the line 111 ('Fig. 10) completed by the closing of the arm 107, and includes a multiple relay switch T similar to the multiple relay switch of Fig. 7. It 1ncludes a series of switch arms 114 to 118 operated by the solenoid bar 119 and adapted to engage, when closed, the contacts 120 to 124. The bar is held yieldingly to the left by the s ring 125 and is moved to the right to close t 1e switch

arms

114, 116, 117 and 118 and to 0 en the arm 115, when the coil 126 is energized. The closing of the

arms

114, 116 and 118 completes thecircuits to the motor A, while the openin of the arm 115 breaks the circuit through t e magnet coil 1,

which holds the air valve open, so that the energizing of the coil 126 and the moving of the bar 119 to the right results in the starting of the motor A and the release of the air from the cylinder 27, permittin the runner to move down by gravity and engage the lass. The members 0, 0, 0 are thermal reay switches lying in the circuit, which energizes the coil 126, such switches being 0 ened by the heating coils p p, p in the t ree lines of the circuits of the motor A, the principle of operation of these switches and their functions corresponding to those of the switch N, heretofore described.

Other apparatus used in connection with the grinding unit A, and the control panel S, as just described, are (see Fi 5") the switches 1' and s, the safety switch IT, the watt meter V, the start button W, the stop button X, the up and down switch Y and the slow drop out relay Z. The switches r and s are arranged so as to be closed when the runner reaches its u per limit of movement and to open when t e runner starts down from its upper position. The switch 1' lies in the circuit including the coil 126 ofthe multipleswitch T, so that the motor A cannot be started unless the runner is in its upper position. The switch 0 lies in a circuit, which short circuits the watt meter V, so that the watt meter is protected a ainst the heavy current flowing throu h t e motor circuit when the motor is -tart1ng. When the motor moves down, the switches r and a open. Fig. 6 shows the switches r and s in detail. The switch arms are held in en agement with the contacts 127 and 128 by t e springs 129, which are attached to the crank arms 130 on which the switch arms are mounted, the crank arms being pivoted at 131. A pair of depcndin rods 132 engage a plate 133 lying beneath t e lever arm 12, which su ports the runner. When the runner moves own, thus allowing the plate 133 and rods 132 to move up, the springs 129 cause the arms r and s to move away from the contacts 127 and 128. When the runner moves up again, the rods 132 are moved down, closing the switch arms. In order to permit the closing of the switch arms by hand when the runner is down, the dependent chain 134 is rovided. This would permit the starting of t e motor with the runner in lowered position and would short circuit the watt meter at such starting time. i

The safety switch U when in the position shown completes the circuit through the coil 126, which closes the multiple switch T. If this switch is moved down and breaks this circuit, it is im ossible, therefore, to start the motor A. his switch is designed to be operated by a key and is locked in open position when re airs or other work is being done of such a cliaracter that the accidental starting of the motor would endanger the workmen.

The stop and start buttons X and W are of the type which are yieldingly held in the positions shown and return to such positions after the o crating pressure is released. As later descri d, t se buttons with their connections permit t e stopping and starting of the motor A independent of the rest of the runner motors B to F. Similarly, the switch Y may be moved from the open posit-ion shown to closed position to cause the runner of the independent of all the other runners and may then be moved back to the position shown to cause the unit A to move down again to grinding position, this being accomplished grinding unit A to move up without stopping the rotation of the runner.

11 3 leading from the re ay A,

potential coil were supplied with three phase current. This is a matter of considerable economy because each of the seventy odd surfacing units inthe system must be provided with its own watt meter to indicate the amount of work which each runner is doing. The slow drop out meter Z has its coil -141 energized by current su plied from the line l and this coil acts to pull the solenoid bar 142 to the ri ht against thetension of the spring 143, so t at the arm 144 engages the contact 145 until the circuit from 113 is broken by the move-' ment of the arm 98 of. the relay A to the left. The relay is of the slow drop out type, so that after the circuit through the coil 141 is broken, the arm 144. remains closed: long enough to permit the arm 107 of the relay A to be closed, and for the current thus supplied from the line 111 through the coil 126 of the multiple switch T and through the arm 145 to close such multiple switch I T, the purpose of this arrangement appearing later in connection with the description of the operation.

Direct current is supplied to the system from the

lines

146 and 147, and 148 and 149 past the switches a and b. This current is utilized in operating the coil'52 of the mul-. tiple switch M, the coil 126 of the multiple switch T; and the

coils

96 and 106 of the relays A to F Alternating current is supplied from the transformer w1ndi ng 212 for operating the coil 69 of the multiple switch P, the coil 150 of the contact ma ing voltmeter 0 (later described), the coils 78 of the time relays A to F", and the motors of such last relays.

The main supply of three-phase alternating current is supplied from the buss lines 151, 152 and 153. In order to operate the watt meters on a relatively low volta e, so that chea er instruments may be emp oyed, the trans ormer 154 is used, which gives the desired reduced voltage on the

lines

137, 138, 139 and 140, heretofore referred to, in connection with the watt meters V. All of the runner driving motors, including A and C are supplied from the

lines

151, 152 and 153 by the

lines

155, 156 and 157 and 158, 159 and 160, respectively, while the table driving motors G and H are supplied by the

lines

161, 162 and 163, in which lines are located the switches e and f, the latter switch having connected to work with it the switch arm 9 lying in the direct current line, which energizes the coil 52 of the multiple switch M. A number of other hand operated switches h, h, h are also located in the same direct current line, and located at intervals along thelength of the line of surfacing units. By opening any one of these, the circuit through the operating coil 52 of the switch M is interrupted and this results in the stopping of the table drive motor G and of all the runner drive motors A to F'- and the raising of the runners driven thereby. These are emergfncy switches, as they rovide for the quic stopping of all of the riving motors from any point along the system in case of accident. They, are shown as double, the right hand side of each switch controllin r a second direct current .circuit 165, whic in turn governs'equipment .on another panel duplicating that of the panel J and includin a multiple switch similar to the switch .This other switch," when c'lose'd, completes the circuits from the source of alternatm current to the duplicate drive motor H. Tiis is an obvious matter of duplication in the wiring arrangement and is, therefore, omitted, no claim being made to the feature of using a duplicate table drive motor, as this is a common expedient in other relations for adding to the certainty of operation.

The. motor G is provided with a watt meter i, which like the watt'meter V has one terminal 166 of its potential coil connected to the neutral line and the other terminal 167 connected to one of the other alternating current supply lines 139. The contact making volt meter 0 (Fig. 5) whose coil lies in the alternating current line from the transformer winding 212, serves to cause a lifting of the runners and the interruption of the current supply to the runner motors. The coil operates the solenoid bar 168 pivoted to the contact arm 169, which is normally held closed by the coil acting upon the solenoid bar. When the potential in the AC lines 151, 152-and 153 drops below a certain point, a corresponding decrease is registered in the transformer winding 212, and the tension spring opens the contact arm 169, and interrupts the AC current through the coil 69 of the multiple switch S, so that such switch opens and results in the cutting off of current to the runner driving motors in timed sequence (through the intermediary of the time relays) and in the raising of the runners. When the volta e rises again, the arm 169 closes again, and t e time relays are actuated in sequence to again securea flow of current to the runner motor, to which the current flow has been discontinued, all of which is more-fully set forth in the description of the complete operation which follows.

The wiring diagram of the connections for the motor G (Fig. 5) discloses a pilot motor transformer j, a split field pilot motor is and a pilot motor limit switch Z, which in connection with the slow and fast buttons 0 and p and the switch arm 50 of the switch M, control the speed of'the motor G, but no description of these parts or their functioning is regarded as necessary, as they involve standard equipment well known in the art and have nothing to do with the present invention, the showing in the drawings of slow drop out relay these parts being included merely to make the wiring diagram complete.

In starting the operation of the system, the hand 0 rated switches are all closed, and it Willa assumed that all of the runners are in upper osition, the switches r and a are closed, tii e push buttons are all spring held in the positions shown in Figs. 5, 5 and 5", none of the motors of the system are operating, and all of the coil operated relay switches are 0 11, except that of the i The coil 141 of such relay Z is energized at this time by direct current from. the line 146 through the line 88 to the relay A (Fig. 11) through the arm 98, the line 113 and the lines 171 and 172 to 0 negative return line 173. The operation is started by ressin down the start button K of the pane J, an holding it down until light shows in the lamps 173, after which the button may be released,

Bermitting it to return to open position.

irect current flows to the button contacts from the line 146 through the line 174, past the contacts'of the buttons K and L, through a further section of the line 174 to the coil 52, through' a further section of the line 174 to switch 9, through a further section of the line 17 4 to the switch N, through this switch and the further sections of-the line 174 leading past all the emergency switches h and back to the negative'side of the switch a. The coil 52, thus energized causes the switch M to close, thus completing the three

circuits

175, 176 and 177 leading from the AG lines 161, 162 and 163 to the table drive motor G, such current flowing through the

contact arms

45, 46 and 47 (Fig. 7), the circuit 175 passing through the current coil of the watt meter The other table drive motor is similarly started at the same time by current through the line 165, heretofore referred to, which is in parallel with the line 174 and passes to a planel, which includes equi ment similar to t at of the panel J.

T e closing of the switch M also completes another .circuit due to the closing of the arm 49, such circuit including the AC transformer winding 212 and the closing coil 69 of the multiple switch P. This circuit is desi ated as 178. Starting with the right han end of the transformer coil 70, it includes the section 178 leading to the point 179, thefurther section 178 lea from 179 to the arm 49, the further section 178 leading to the int 180, coil 69, section 178, arm 169 an wire 88 to point 181, and section 178 to the left hand end of the transformer coil 212. At this time, the arm 169 of the relay 0 is closed, as its coil 150 is ener 'zed by alternating current from the win 212. The coil 69 now closes the switch g, including the arm 61, so that alternating current from the point 180 asses through such arm to the line 87, and once through the time relay A and back to the oint 181 and winding 212 via the line 88.

he actuation of this relay has been described in connection with Fig. 9, the current from the line 87 passing through the coil 78 and the windings of the motor 80, so that the sprin 77 is placed in tension and the arm 83 driven from the motor trips the catch 84, after a redetermined interval of time, the arm 70 t en being swung to the right by the spring 77, so that the contact ends 72 and 73 engage the contacts 74 an 75, thus completing the circuit between the

lines

94 and 88. Direct current now flows from the line 88 to the line 94 via the arm 70 and thence through the -coil 96 of the relay A from which it returns to the negative line 147 via the line 95. This causes the arm 97 to swing to the left so that direct current from the line 88 flows through such arm, the line 105 (Fig. 11), and the coil 106, to the negative return wire 95. The flow of current throu h the coil 106 closes the arm 107, so

that 'rect current from the positive line 88 flows through the am 107 to the point 183.

From the point 183, the current from the line 88 makes two circuits, one of which flowing through the line 111 energizes the operating coil 126 of the multiple switch T as later described), while the other passes t rough the line 185, the resistance 186, section of line 185, arm 48, section of line 185, contacts of stop button L, section of line 174, coil 52, section of line 174 switch g, section of line 174, switch N, and line 174 leading past the switches it back to the negative line 147 at switch a, as heretofore described. This provides a second or holding circuit through the coil 52, so that, when the button K is released, breakin the circuit at this oint, the switch M wifi still be held closed.

his circuit also provides for lighting the lamps 173, as these lights'are in shunt with a part of the circuit. Starting at the switch N, this shunt circuit includes the section of line 185 to the right of the switch N, the lam s 173" and the section of the line 185 lea mg to the end of the resistance 186. The lighting of the lam s 173 therefore, indicates the time when e holding circuit 185 is completed b the closing of thecontact arm 107 of t e relay A'-, so that the contacts of safety switch button U, and section of line 111. to negative return line 173. The contact arm of the relay Z was held closed long enough to permit the energizin of the coil 126, due to its slow openingc aracterist-ic, the coil 141\having its current from its suppl circuit 171 cut 011', as soon as the arm 98 o the rela A, moved to the left under the influence o the coil 96, breaking the circuit from the line 88 to the line 113. The current, as thus briefly supplied to the coil 126, moves the switch T to closed position. The closing of the arm 117 of the switch T establishes a new circuit through the coil 126, which acts as a holding circuit, after the other circuit through the coil 126 is broken at the slow drop out relay Z. This circuit comprises the section pf heavy, the coils of the thermal relay swithl-ie's' line 111 leading to the ush button X, line 186, arm 117 of switch section of line 186, coil 126, section of line 111, thermal relay switches o, o, 0, section of line 111, button U, and section of line 111 back to negative line 173. The switch T is thus closed and held closed, after the relay Z opens, and this circuit is maintained after the switches 1' and s are opened by the downward movement of the runner, as the holding circuit, as above described, does not. pass through these switches. I p

The closing of the switch T completes the three

circuits

155, 156 and 157 through the

contact arms

114, 116 and 118 and through the windings. of the motor A, so that the rotation of the motor and the surfaing runner starts upon the closing of the switdh.

In case the load on these circuits becomestoo and.

0, o, heat up and open the switchis and break the circuit through the line} coil 126, so that the switch T opens.

At the time the motor A is thus started and while in upper position, the switch a short circuits the line 157, which passes through the current coil of the watt meter V, so that at this moment of high load, when the motor is starting, the watt meter is relieved of this current, which flows from one section of the line 157 to another section thereof via the line 187 and switch a.

The closing of the multi le switch T also results in the lowering of t e motor A and its runner carried by the arm 12. This is caused by the openin of the'arm 11-5 of the switch T (Flg. is moved to the right by the coil 126. This interrupts the

circuit

187, 187 from the line 188 back to the line 173 through the winding I, so that the valves 39 and (Fig. 4) are moved to the positions of Fig. 4 by the spring 41, thus cutting off the supply of air to the cylinder 27 and permitting the air therefrom to exhaust through the passage 31 and opening 43. As a result, the arm 12 and the runner 11 carried thereby begin to move as the solenoid bar switches r an s. The opening 0 the switch r interrupts the closing circuit of the switch A T through the coil 126, so that only the holding circuit through such coil remains effective, while the o ening of the switch a directs the current 0 the motor circuit line 157 through the watt meter V, so that from this. time -on the watt meter registers the current used by the motor A. a

11' itnow becomes necessary to stop the motor A and lift-the runner independent of the rest of the system, this can be done by pushing the stop button X, which interrupts the holding circuit fiowin through the lines 111 and186 and thecoi 126 of the switch T, so thatsuch switch opens, breaking the

motor circuits

155, 156 and 157 and closin the arm 115 so that the winding of the coil I is energized and the runner is lifted. After the button X is released and moves back to closed sition, the switch -T still remains open, since the holding circuit through the 0011 126 has been opened by the fin er 117 ,and since the closing circuit throu the relay Z is now broken at such rela he motor can be started and lowered, however, by closin the start button W, which com letes the closingcircuit through the coi 126, so that the switch T is a in closed and the circuit throu h the coil I is broken. 1 11811101301, there ore, starts. again and the runner is lowered, and this condition is. continued after the button .W is released and opens, since the holding circuit past the button X and through the

lines

111 and 186 is again made efi'ective.

In case it is desired to raise the runner 'and lower it again without stopping the rotation of the runner, this is accomplished 187, t e winding I, through a section of the line 187 passing a ta connection on the safety switch U, throng a section of the line 187 to a tap 190" on the line 189, through 7 a section of the line 189, through the contacts 191 of the switch Y (now assumed closed), through the

lines

192 and 172 to the negative bus 173, and the winding I thus being ener zed, the runner moves up. When the switc Y is moved back to the position shown, this breaks the circuit through the winding I, so'that the runner again moves down. i I f I The surfacing unit A is thus under independent coritrol, so that the runner maybe moved up or down or sto ed or started as desired. This unit, as W5 as all the other units may now be stopped from the master control panel J. This is accomplished by pressing down the stop button L. This interrupts the holding circuit through the'coil.

52, as heretofore described, so that the multiple switch M opens, breaking the three

circuits

175, 1 76 and 177 through the table drive motor G at the

contact arms

45, 46 and 47, so that this motor stops. The opening of the switch M also breaks the alternating current circuit through the arm 49, so that the circuit- 178 leading through the coil 69 of the switch P (Fig. 821 is interrupted and such switch opens. T e openin of the arm 61 interrupts the circuit 8 through the coil 78 (F1g.9) of the time relay A so that the spring 77 opens the switch arm 70. The opening of this arm interrupts the

circuit

88, 94 to the coil 96 and return line 95, so that the switch arms 97 and 98 open to the position of Fig. 11, thus interrupting'the circuit from the line 88 to t e return line 95 via the arm 97, wire 105, 0011 106 and wire 105. This permits the arm 107 to open,-interrupting the circuit through the line 111.

Q! As heretofore explained, the circuit 111 is the one throu h which current flows to the coil 126, whic holds the multiple switch T closed, so'that when this circuit is interrupted, the switch opens, interrupting the,

three

circuits

155, 156 and 157 of t e runner driving the motor A and closes the circuit through the magnet winding. The rotation of the motor is, therefore, stop ed and the runner is raised by the air c lin er 27. The movement of the arm 98 o the relay A to its original position, as illustrated, again com letes the circuit through the coil 141 of t e slow drop out relay via the

lines

113 and 172, so that the arm of this relay is closed, placing the arts in their original position, as described in the beginnin and so that the starting of the motor A may be accomplished by )ressing the start button K, as heretofore escribed. The upward movement of the runner supporting arni 12 also closes the switches r and s, so that the motor can be started in its upper position and so that the watt meter V is short circuited during such starting movement. The fast and slow buttons p and 0 (Fig. 5) operating in conjunction with the pilot motor In control the speed of rotation of the motor G, and the arm 50 of the switch M, which is normally closed, insures that in starting the system, the motors will operate at slow speed until the fast button P is rcssed down.

The foregoing sets forth t e operation involved in starting only one of the motors of the group to which t e runner motor A belongs. It will be understood that the wiring and control apparatus for each of the other motors of the group is the same, direct current being supplied to such other from the relays A and A. The control of the other groups B to F is similarly affected through the relays B to F and B' to F, the relays B to F being adjusted so that they close in sequence one after the other after A closes. For instance, the arm of the relay B ma' be set to close onethird of a second a ter the arm 70 0f the relay A closes and the other relays C to F will similarly close in uence at intervals of two-fifths of a secon The grou s of runner driving motors will, therefore, lie

'- started in sequence at intervals of one-third of a second thus distributing the load upon the

supply line

151, 152 and 153.

The manner in which another group of motors C areconnected to the s stem and operated from the relays C and is illustrated in Figs.' 5 and 5". Here the closing of the arm 107 is accom lished in the same manner as the closing 0 the am 107, heretofore described, and the closing of this arm secures the supply of direct current from the line 88 to the line 111', such line corresponding to the line 111. Similarly, direct current passing through the relay C is 'sup lied to the line 113', such line corres n ing to the line 113, heretofore descri The line control of the runner motor C and the functioning of the appsratus associated therewith merely duplicates that for the motor A and the operation is obvious without further description or explanation, the reference numerals and letters employed being the same as for the motor A, except in the application of the prime mark to eachof such numerals and letters. The other rela s B, D, E and F and B,

.D', E and I control the contact arms 107?, 107', 107 and 107 from which the

lines

111, 111', 111 and 111 are supplied with direct current and lead to the other groups of runner motors B, D, E and F in the same manner as illustrated for the lines 111 and 111'. Similarly, the lines 113 113 113 and 113 correspond in function to the lines 113 and 113', in their control of the several slow drop out relays corresponding to the relays Z and Z.

The contact making voltmeter c functions in connection with the switch P to cause the runner driving motors tobe disconnected from the power lines in groups in regular sequence with a definite time interva between groups in case of a failure of the alternating current su ply. Further, the arrangement is such t at should the failure of the alternating current power supply be just a dip of voltage and of ver short duration, so that the voltage is bac on the line before the sequence is completed the groups remaining on the line stay on, and the groups that have been out 01f are members of the group by the

lines

111, 113,, again started in their regular order with a 173 and 188, so that the group is controlled definite time interval between groups III The coil 150 is energized from the winding 212 of the transformer which is operated from the alternatin

current power lines

151, 152 and 153, so t at the voltage through the coil 150 fluctuates with that in the power lines. In case of a failure of the power supply, the voltage in the coil 150 drops and the spring 170 opens the contact arm 169, thus interrupting the current through the coil 1S different. In such case, although all of .the contact arms 70 0 en immediately, when the switch P o ens, t e opening of the

arms

107, 107, etc. 18 delayed and occurs in time The first contact arm of the

series

107, 107, etc. which opens upon theopening of the contact arms 70 is the arm 107. This is not instantaneous upon the breaking of the circuit through the coil 96, as the residual magnetism in the coil prevents the arms 97 and 98 from instantly moving to the right. During this interval of delay, current continues to flow through .the coil 96 of the next relay B from the line 88 via the arm 98 and line 190, so that until the arm 98 opens, the current continues to flow through the coil 96 and the residual magnetism in this coil 96' then keeps the arms 97' and 98' closed a definite interval after the arms 97 and 98 open. As a result, the arm 107 opens at a definite period after the arm 107. Similarly, the arms of the other relays C to F open at successive spaced intervals. In case the voltage is restored in the power circuit when only a part of the arms 107 to 107 have opened, the contact arm 169 of the voltmeter c closes followed by the closing of the switch P. If only the first two of the relays A and B have opened their

arms

107 and 107 when this occurs, the rest of them will not open up, since a flow of current is restored throu 11 their coils 96 t6 96 due to the closure of t e arms 63 to 66 of the relay P. For instance, the closing of the arm 63 permits a flow of current through the coil 96 'from the line 88, via such arm 63, and the line 191. The closing of the

arms

64, 65 and 66 performs a similar function with relation to the coils 96 to 96 of the relays D E and F The supply of current is -now restored to the runner motors of the groups A and B, due to the closing of the arm 61 of the switch I, the operation being the same as heretofore described in connection with the preming of the start button K, namely, the arms 70 of the relays A and B close in timed sequence, followed by the closing of the arms 107 and 107 A Fig. 12 illustrates a modification involving the use of a different form of prime mover for swinging the lever arm 12, which su ports the motor and runner. In this modification, the prime mover is an electric motor which operates through a worm and threaded shaft to raise and lower the arm 12. Direct current is employed to operate the motor and the control system is very similar to that described-inconnection with the apparatus using the air cylinder as the prime mover for controlling the up and down movement of the arm 12, and the parts carried thereby.

Referring to the drawing, the arm 12 carrying the meter G and the runner, has pivotally mounted in its outer end, the block 195, through which is threaded the operating shaft 196, carrying at its up or end a worm wheel in the caslng 197. I his worm wheel is driven by a worm carried by the shaft 198, and this shaft is driven from the motor 199 through the intermediary of the

gears

200 and 201 carried respectively by the motor shaft and the shaft 198. The motor 199 is of the split field type arranged so that current from the line 202 passing through the coil 203 and line 204 rotates the motor in a direction to lower the runner, while current from the line 202 passing through the coil 205 and line 206 rotates the motor in a direction to raise the runner.

The motor G is driven from current supplied by the

lines

158, 159 and 160 and these circuits are controlled by the switch T having the closing coil 126 and similar throughout in construction to the switch T. The coil 126 is energized by direct current supplied from the line 111", this circuit corresponding to the

circuits

111 and 111 of Fig. 5 the contact arm 144" of the slow drop out relay Z being held shut at this time b current supplied from the line 113 through the line 171". After the switch T is closed, a holding circuit is established through the arm 117 via the

lines

111, 186, 111, switch U and section of line 111, so that after the circuit through the line 111 is broken b the opening of the switch 7-, the switc T will still remain closed, subject to interruption when desired b pressing the stop button. A limit switch 207 is provided in the line 206, such switch being opened by suitable means (not shown) when the runner approaches its upper 1 osition and being closed again automatical y when the runner starts down.

If the runner is in its lower position and the current supply to the coil 126 is cut off,

permitting the switch T to open, such 0 ening closes the arm 115 so that current owe to the motor 200 from the line 202 and back to the ne ative line 173, via the following circuit ine 206, arm 115", line 208, arm U and section of line 111. This causes the motor to rotate so as to raise the runner, such movement continuing until the limit switch 207 is opened automatically as the runner reaches its u ward limit of move ment, thus causing t e motor to stop. In order to cause the motor 200 to rotate in the reverse direction to move the runner down, it is necesar to ress in the button Y". This completes t e circuit from the positive line 202 through the motor and back to the negative line 17 3 via the following connections:line 204, switch arm U, line 204,

contacts 208- of switch Y, line 204, switch arm U and line 111. The buttons Y and Y are connected together and spring controlled, so that when either button is released, from manual pressure, the buttons return to the neutral position shown. The buttons Y is, therefore, released when the motor 202 has rotated sufliciently to lower the runner to surfacin position. The motor may now be cause to 0 rate to raise the runner by Y. The arm 115 0 the switch T" is now open, but the up circuit through the line 206 back to the negative line 173" is completed from the point 209 via the line 210, the contacts 211 of the button Y, and the line 204.

The motor G may be stopped and the runner lifted by pressing the stop button X and may be started by pressing the start button W, the pressing of the button X? serving to interru t the holding circuit 186 to the coil 126, w ile the pressing of the button W completes the closing circuit 111 through such coil.

What I claim is:

1. In apparatus for continuously surfacing sheets of material, a series of surfacing machines, each having a vertically movable driven runner, supporting means for carrying a series of sheets of material to be surfaced continuously beneath the series of runners, a prime mover at each machine adapted to raise the runner thereof out of contact with the sheets carried upon the supporting means, an electric motor for driving said supporting means, a power circuit for suppl ing current to said motor, and means, includin a relay governed from said ower circuit, for securing the actuation 0 said rime movers to lift the runners upon a ailure of the power supply to said circuit.

2. In apparatus for continuously surfacing sheets of material, a series of surfacing machines, each having a vertically movable runner, an electric motor for rotating each runner, and means for sup lying current thereto, su porting means or carrying a series of s eets of material to be surfaced ressing in t e button continuously beneath the series of runners, a prime mover at each machine adapted to raise the runner thereof out of contact with the sheets carried upon the supporti means, an electric motor for driving sai supporting means, a power circuit for an plying current thereto, and means, inclusmg a relay governed from the power circuit, for cutting olf the supply of current to the runner rotating motors, and for securing'the actuation of said prime movers to lift the runners upon failure of the power supply to said circuit.

3. In apparatus foroontinuously surfacing sheets of material, a series of surfac' machines, each having a vertically movable driven runner, supporting means forcarrying a series of sheets ofmaterial to be surfaced continuously beneath the series of runners, a prime mover at each machine adapted to'raise the runner thereof out of contact with the sheets carried upon the supporting means, an electric motor for driving said. supporting means, a power circuit for supplyin current to said motor, and means, mclu ing an automatic switch governed by said power circuit and relay means, for securing the actuation of said prime movers to lift the runners in case the current flow through said motor increases beyond a predetermined point.

4. In apparatus for continuously surfacing sheets of material, a series of surfacin machines, each having a vertically movable runner, an electric motor for rotating each runner, and means for supplying current thereto, su portin means or carrying a series of sli eets 0 material to be surfaced continuously beneath the series of runners, a prime mover at each machine adapted to ralse the runner thereof out of contact with the sheets carried upon the supportin means, an electric motor for driving sai supporting means, a power circuit for supplying current thereto, and means, including an automatic switch governed by said power circuit and rela means, for securin the actuation of sai prime movers to li the runners and to cut off the flow of current to the runner rotating motors in case the current flow through said motor for moving the supporting means for theglass increases above a predetermined point.

5. In apparatus forcontinuously surfacing sheets of material, a series of surfacing machines, each having a vertically movable runner, an electric motor for rotating each runner, and means for supplying current thereto, supporting means for carr ing a se-- ries of sheets of material to be sur aced continuously beneath the series of runners, a prime mover at each machine adapted to raise the runner thereof out of contact with the sheets carried upon the supporti means, .an electric motor for driving sai supporting means, a power circuit for supplying current thereto, a relay for each machine for controlling the flow of current to the runner rotating motor and to said prime mover for controlling its operation, a master relay for controlling all of said relays, and also the flow of current to the motor which drives said supporting means, a manual control for said master relay, and still other relay means also controlled from the master relay and from said power circuit and arranged to open and cause the opening of the first relays and the actuation of the prime movers to raise the runners upon a failure of the power supply to said power circuit.

6. In apparatus for continuously surfacing sheets of material, a series of surfacing machines, each having a vertically movable runner, an electric motor for rotating each runner, and means for supplying current thereto, supporting means for carrying a series of sheets of material to be surfaced continuously; beneath the series ofvrunners, a prime mover at each machine adapted to raise the runner thereof out of contact with the sheets carried upon the supporting means, an electric motor for driving said supporting means, a power circuit for supplying current thereto, a relay for each machine for controlling the flow of current to the runner rotating motor and to said prime mover for controlling its operation, a master relay for controlling all of said relays, and also the flow of current tothe motor which drives said supporting means, a manual control for said master relay, and an' automatic switch controlled by the flow of current to the motor which moves said supporting means and adapted, when such flow rises above a predeterimned point, to open and cause the opening of said master relay, which in turn causes the opening of the other relays, cutting oil the supply of current to the runner rotating motors and causing the actuation of the prime movers to raise the runners.

7. In apparatus for continuously surfacing sheets of material, a series of surfacing machines, each having a vertically movable runner, an electric motor for rotating each runner, and means for supplying current thereto, supporting means for carrying a series of sheets of material to be surfaced continuously beneath the series of runners, a prime mover at each machine adapted to raise the runner thereof out of contact with the sheets carried upon the supporting means, an electric motor for driving said supporting means, a power circuit for supplying current thereto, a relay for eachmachine for controlling the flow of current to the runner rotating motor and to said prime mover for controlling its operation, a series of time relays adapted to close in sequence after actuating current is supplied thereto and controlling said first relays, a master relay controllin the flow of actuating current to the time re ays, and also the flow of current to the motor, which drives said glass sup orting means, and a manual control for sal master relay, said relays for each machine being arranged, when closed from the master relay, to secure aflow of current to the runner drive motors, and to cause the actuation of the prime movers tosecure the lowering of the runners, and when opened from the master relay, to cut off the flow of current to the runner drive motors and to cause the actuation of the prime movers t secure the raising of the runners.

8. In apparatus for continuously surfacing sheets of material, a series of surfacing machines, each having-a vertically movable runner, an electric motor for rotating each runner,'and means for supplying current thereto, supporting means for carrying a series of sheets of material to be surfaced continuously beneath the series of runners, a prime mover at each machine adapted to raise the runner thereof out of contact with the sheets carried upon the supporting means, an electric motor for driving said supporting means, a power circuit for supplylng current thereto, a relay for each machine for controlling the flow of current to the runner rotatin motor and to said prime mover for control ing its operation, a series of time relays adapted to'close in sequence after actuatlng current is supplied thereto and controlling said first relays, a master relay controlling the flowof actuating current to the time relays, and also the flow of current to the motor, which drives said glass supporting means, a manual control forsaid master relay, and means governed from the power circuit for causing the opening of the time relays upon a failure of the power supply to said power circuit.

9. In apparatus for continuously surfacing sheets of material, a series of surfacing machines, each having a vertically movable runner, an electric motor for rotating each runner, and means for sup lying current thereto, supporting means fbr carrying a series of sheets of material to be surfaced continuously beneath the series of runners, a prime mover at each machine adapted to raise the runner thereof out of contact with the sheets carried upon the supporting means, an electric motor for driving said supporting means, a power circuit for supplying current theretoea relay for each ma chine for controlling the flow of current to the runner rotating motor and to said prime mover for controlling its operation, a series of time relays adapted to close in sequence after actuating current is supplied thereto and controlling said first relays, a master relay controlling the flow of actuating our-