CA1111649A - Timing pulse generator for a glassware forming machine - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE

A glassware forming machine includes a gob distributor for distributing molten glass gobs to individual sections of the machine at a predetermined rate, a drive responsive to elec-trical power of a selected frequency generated by a power source for driving the gob distributor at the predetermined rate and an automatic control device responsive to timing signals for controlling each of the individual sections in a predetermined timed sequence of steps for forming the glassware. The power source generates the timing signals at a frequency proportional to the selected frequency of the power source. Each piece of glassware is formed during a machine cycle which is related in duration to the gob distribution rate and typically is de-fined in terms of 360°. The power source includes a timing pulse generator which synthesizes the timing signals from the power source electric power frequency at the frequency required for defining 360° per machine cycle.

Description

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The present invention relates in general to control systems for glassware forming machines and in particular to a timing pulse generator for generatiny clock pulses for con-trolling individual sections of the machine in a predetermined timed sequence oE steps.
In a glassware forming machine known as an IS or in-dividual section machine, each individual section includes a plurality of means for performing a predètermined sequence of steps in a timed relationship to form the glassware. The form-ing means are generally powered by pneumatic motors controlledby a valve block which, in turn, is controlled by a rotating timing drum. Glass is melted and formed into gobs which are yuided to the individual sections by a gob distributor. Each section of the machine produces glassware from the gobs, which glassware is placed on a dead plate for push out onto a flight conveyor for removal to a lehr for annealing and cooling and - any other treatment.
The individual sections are operated in a predeter-mined sequence at a relative phase difference to receive gobs from the gob distributor in ordered sequence. As one oi the sections is receiving a gob from the gob distributor, another ~ one of the sections is delivering a finished article of glass-`: ware to the conveyor, and the other sections are performing ` various ones of the forming steps. Furthermore, two molds can ` be provided in each section whereby a gob is received in a first mold, called the blank or parison mold, for the initial process of forming a parison, followed by transEer of the parisorl to a second mold, called the blow mold, ~or final blowing oE the article. ThlJs, each sec-tion of the machine i5 operating simul-taneously upon two articles.

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' -~` l The timing drum includes a plural:ity of adjustable cam members positioned around the cylindrical periphery thereof for mechanically operating the pneumatic valves in the valve block in a predetermined sequence. The timing drums for all the sections are driven in synchronism with the gob distributor and -the conveyor resulting in a continuing flow ~f ~lass gobs into the machine and a continuing flow of glass down the con-veyor.
However, it is difficult to adjust the timing of any Of the means for performing the forming steps in an individual section. The cam members are generally mounted in annulax grooves in the drum surface and are held in position by a clamp-ing device such as a nut. As the drum is rota~ing, the nut must be loosened, the cam member moved in the groove and the nut tightened again. Such operation is undesirable since it ;` is difficult to obtain accuracy and is subject to mechanical wear resulting in changed timing.
One solution to the timlng problem is disclosed in U.S. Patent No. 3,762,907, issued October 2, 1973 to R.M. Quinn et al, wherein the valves of the valve block are actuated by solenoids controlled by an electronic control system~ The con-trol system receives clock signals and reset signals from a pair of pulse generators driven by a common drive shaft for the machine.
Another solution to the timing problem is disclosed in U.S. Patent No. 4,007,028, issued February 8, 1977 to A.T.
Bublitz et al, wherein individual drive motors are used to drive the gob feeder, gob dis-tributor and take--off conveyor. Each dri~Je motor is supplied with power from its indlvidual inverter ;~ 30 and frequency control means is utilized to adjust the speed :

; of the mo-tors. Posi tion transducers generate siynals to a com-puter to indicate the positions of the gob feeder and gob dis~ri-bu-tor and the eomputer also reeeives signals indicating actua-tion of the glassware forming elements. The computer stores information as to the timing of th~ actuation of the forming elements and is responsive to a eloek for generating control signals to the solenoids for aetuating the valves of the valve block.
- It is an object of the present invention to improve the performance of glassware forming maehines.
It is another objeet of the present invention to re-duce the circuitry required to eontrol an individual seetion glassware forming machine by eliminating a separate clock source.
The present invention provides an apparatus for form-ing glassware comprising means for forming gobs of molten glass and for distributing the gobs to an individual section glass-~` ware forming machine at a predetermined rate; eleetrie means fox generating eleetrie power at a seleeted frequeney; fre-queney proportioning means eonneeted to the eleetrie power generating means for generating timing signals at a frequeney proportional to the seleeted frequeney; electrie drive means ;` responsive to the eleetrie power for driving the means for form-ing and dis-tributing gobs at the predetermined rate; and a eon-trol circuit responsive to the -timing signals for cyclically controlling each inclividual seetion of the individual section machine in a predetermined time sequence of steps for forming glass from the gobs.
Typieally, the forming steps perEormed by the elements of the individual seetions of the maehine are timed by divld:ing the maehine eyele into 360 and refereneinc~ the steps to the . .

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- start of the cycle wi-th -the sequence of steps for each indivi-dual section o~fset by a different number of degrees. The fre-quency proportioning means may generate a timing signal at a frequency which provides 360 pulses per machine cycle. This timing signal frequency is synthesized from the selected power frequency by dividing -the selected power frequency by a first factor M and applying the divided by M frequency signal to one input of a phase locked loop. The phase locked loop ou-tput signal frequency is divided by a ~actor of N and the divided lQ by N frequency signal is appl:ied to the other input of the phase locked loop. The phase locked loop is responsive to any error between the divided by M frequency and the divided by N fre-quency to change the outpu-t signal frequency so that the two input frequencies are equal. Therefore, the output signal fre-quency is equal to the inverter power frequency scaled by a factor N/M such that, by the selection of the proper values for N and M, the output signal frequency will provide 360 pulses ; per machine cycle for any predetermined gob feed rate.
` In an alternate embodiment, an oscillator generates a frequency reference signal which is frequency divided to ;~ generate a control signal to an inverter drive for generating electric power to the drive motor. The frequency reference signal is also frequency divided to generate the timing signal clock pulses typically at 360 pulses per machine cycle. In both embodiments, the clock pulse train is further frequency divided to generate reset pulses to define the end and beginning of successive machine cycles.
The i.nvention will be more readily understood Erom the following description of preferred embodiments -thereof given, by way of example, with reference to the accompanyiny drawings, in which:

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~,, Fig. l is a block diagram of a pxlor art glassware forming apparatus;
Fig. 2 is a block diagram of a glassware forming ap-paratus embodying the present invention;
Fiy. 3 is a block diagram of the timing circuit of Fig. 2;
Fig. 4 is a block diagram of an alternate embodiment of the timing circuit;
; Fig. 5 is a table of timing values for the glassware forming apparatus of Fig. 2; and Fig. 6 is a generalized block diagram of the timing circuits embodying the present invention.
There is shown in Fig. l a block diagram of a glass-ware forming apparatus according to the prior art. In this apparatus, the machine control circuit controls the actuation of the glassware forming means in accordance with information on the positions of the gob feeder and the gob distributor in their respective cycles of operation.
An individual section glassware forming machine 11 has a plurality of individual sections (not shown) which receive gobs of molten glass from a gob distributor 12 which in turn receives the gobs from a yob feeder 13. The gob distributor 12 and the gob feeder 13 are mechanically driven by a pair of drive motors 1~ and 15, respectively, which motors are connected to a supply of variable frequency power generated by an inverter drive 16. The inverter drive frequency is controlled to deter-mine the rate at which the gobs are formed and distributed to the individual sections of the IS machine ll.
Each individual section ls associated with a separate valve block, which valve blocks are designated by the reference ,~

17 in Fig. 1. Each valve block has valves connected -to actuate a plurality of glassware forming means in the associa-ted in-dividual section. The valves in the valve blocks 17 are actua-ted by solenolds which are controlled by a machine control cir-cuit 18 which determines the timiny of the forming steps in accordance with a predetermined sequence of those steps. The control circuit receives information as to the sequence of the steps and the times between the steps from a source ~not shown) such as control switches or a computer program. ~ pair of posi-tion transducers 19 and 21 are mechanically coupled to the drive ` motors 14 and 15 respectively and generate signals representing :; the relative posi-tions of the gob distributor 12 and the gob feeder 13 respectively. The gob feeder 13 represents a typical apparatus fox expelling a quan-tity of molten glass from the forehearth of a glass furnace. Thus, the motor 15 can drive a crank ~not shown) which is connected to reciprocate a plunger (not shown) to expel the quantity of glass. The quantity of glass is cut by shears (not shown) to form a gob which falls into the gob distributor 12. Since the forming of the gob is related to -the rotational position of the drive motor 15, the position transducer 21 generates a signal indicating when each gob is formed. The go~ distributor 12 is driven by the motor 14 to distribute the gobs to the individual sections of the IS machine in a predetermined sequence. Since the distribution of any one gob is related to -the rotational position of the motor 14, the position transducer 19 generates a signal indica-ting when a gob is distributed and to which individual section.
The control circuit 18 responds to the two position transducer signals to determine when -the se~uence of steps for each indivi-; 30 dual section is to be initia-ted in response to each gob formed -;

and distributed.
The machine control circui-t 18 also receives a clock signal from a source 2~ which s,ignal provides a reference -for timing the machine cycle and the sequence of steps. Typically, machine timing is expressed in degrees and a machine cycle is 360 in length. The cycle for each individual section is also , 360 but the cycles for the sections will be offset from the start of the machine cycle by different numbers of degrees to compensate for the difference in gob delivery time to each "' lO section. A glassware forming apparatus as shown in Fig. l is more fully described in the previously referenced U.S. Patent No. 4,007,028.
There is shown in Fig. 2 a block diagram o~ a glass-ware forming apparatus'embodying the present invention. In the prior art apparatus of Fig. 1, the gob distributor motor 14 was considered the zero phase motor and the gob feeder, push-out and con~eyor motors are phased in manually at start-up.
Thus, the timing oE the individual sections relied upon the position of the gob distributor. In the present apparatus, 2Q the IS machine is considered the zero phase motor and the gob feeder, gob distributor, pushout and conveyor motors are phased in. Thus, the timing of the individual sections is fixed and ` the gob dis-tributor is referenced thereto with a correction to the section timing, if needed, supplied by a detection of the gob at the mold to provide a more accurate control of the machine cycle.
As with the apparatus of Fig. l, an individual section '' glassware forming machine 31 has a plurality of individual sections (not shown) which receive gobs of molten glass from a gob '~ 30 ,; ~ - 7 -. distributor 32 which in turn receives -the gobs from a gob ieeder .. 33. The gob distributor 32 and the gob feeder 33 are mechanical-ly driven by a pair of drive motors 34 and 35 respec-tively, which motors are connected to a supply of variable frequency power generated by an inverter drive 36. Each individual section is associated with a valve block, which valve blocks are designated with the reference numeral 37. Each valve block : is connected to a plurality of glassware orming means in th~
individual section or actuating the forming means in a pre-determined timed sequence of steps to form glassware from the gobs supplied by the gob distributor 32. The valves in the valve blocks are actuated by solenoids which are controlled . by a machine control circuit 38 which determines the timed sequence in accordance with a predetermined sequence of steps and timing clock signals generated by a timing circuit 39.
The control circuit 38 receives information as to the sequence of the steps and the times between the steps from .. a source (not shown) of such information. The timing circuit 39 is responsive to the frequency of the inverter drive output power to generate the clock signals. Since the speeds of the . motors 34 and 35 are proportional to the frequency of the power .: generated by the inverter drive, the timing of the forming of the gob by the gob feeder 33 and the timing of the distribution of the gob by the gob distributor 32 are synchronized with the clock signal 39.
; Although the distribution of the gob to each indivi-dual section is synchronized with the clock siynals, the clock signals only provide information as to the rate of yob d:Lstri bution and are utilized as a timing re~erence for the sequence of steps in the machine cycle in a manner similar to the clock : - 8 -.'.` `'' .
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' signals generated by -the clock source 22 o~ Fig. 1. Since -there is no position transducer provided as in the apparatus of Fig.
1, the machine control circuit 3~ has no information as t~ the ~ime of gob distribution within the gob feeder cycle. Therefore, the timing circuit 39 also generates a timing reset signal to the control circuit 38 to initiate the machine cycle. The gob feeder 33 and the gob distributor 32 can then be phased in with reference to the reset signal such that the gob is distributed to -the individual section at the required time in the machine 10 Cycle.
There is also shown in Fig. 2 a gob sensor 41 which generates a signal upon the detection of a gob at the mold in an individual section. A gob detector circuit 42 responds to the signal from the sensor 41 to generate a signal to the control circuit 38 which signal is utilized to adjust the timing of that individual section to the actual presence of the gob rather than to a position related distribution time as was done in the prior art.
There is shown in Fig. 3 a block diagram of the timing 20 circuit 39 of Fig. 2. An input line 51 is connected to the output of the inverter drive 36 of Fig. 2 such that the timing circuit 39 responds to the frequency of the inverter output power to generate a clock pulse train on an output line 52 and reset pulses on a line 53. The inverter power having a fre-quency of F(IN) is an input to a frequency dividing circuit 54 having a frequency division factor of M which circuit genera-tes a signal having a frequency o~ F(IN~/M. The output of the . M circuit 54 is one input to a phase detector 55 in a phase locked loop 56. The line 52 is an output from the phase locked loop 56 on which is generat~d -the clock pulse train at a fre-.. quency F (OUT) . The line 52 is connected to an input of a second frequency dividing circuit 57 having a frequency division factor , of N which circuit generates a signal having a frequency of ::`. F (OUT) /N.
he output of the . N circuit 57 is -the other input to the phase de~ector 55. The phase detector eompares the fre-quencies of the two input signals, F (IN) /M and E'¦OUT)/N, and, if the frequencies are different, generates an error signal.
The error signal is filtered by a low pass filter 58 external to -the phase locked loop 56 and then amplified by an error amplifier 59 internal to the phase loeked loop before being applied to the input of a voltage eontrolled oseillator 61 also internal to the phase locked loop. If the F(IN)/M frequency is greater than the F (OUT) /~ frequeney, the voltage eontrolled oscillator 61 responds to the error signal by increasing the F (OUT) frequeney. If the F ~IN~ /M frequeney is less than the ; F(OUT)/N frequency, the voltage controlled oscillator responds to the error signal by decreasing the F (OUT) frequency. There-fore, the phase locked loop drives -the erxor signal to zero such that F (IN) /M = F IOUT) /N and the loop eircuit remains locked .: with F(OUT) = N.F(IN)/M.
The eloek pulse output line 52 is also connected to an input of a third Erequency dividing circuit 62 having a fre-quency division factor of 360 which circuit generates reset pulses on the line 53. Typically, the timing of the IS machine is based on a full cycle of 360 which is represented by 360 clock pulses. Therefore, -the reset pulses on the llne 53 define the end and beginning of successive machine cycles.
;~ 30 The elements shown in Fig. 3 are commercially avail-```:

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able as integrated circuits or can be constructed from di~crete ' componen-ts in accordance with we],l~known circuits. For example, the dividing circuits 54 and 57 can be a CD 4018A presettable divide-by-N coun-ter, the dividing circuit 62 can be a CD 4059A
programmable divide-by-N counter and the circuit 56 can be a CD 4046 A phase locked loop all manufactured by RCA, Box 3200, Somerville, New Jersey 08876.
There is shown in Fig. 4 a block diagram of an alter-nate embodiment of a circuit which can be used to generate the clock signals and the reset signal to the machine control cir-cuit. A linear voltage controlled oscillator (LVO) 71 is utilized to generate a reference signal F(LVO~ at a frequency sixty times the frequency at which the gob distributor and the gob feeder motors are to be driven. This signal is an input to a frequency dividing circuit 72 having a frequency division factor of ten. The lO circuit 72 generates an output pulse ~; train having pulses with a width approxima-tely equal to two cycles of the input signal. The output of the . lO circuit 72 is connected to a monostable multivibrator 73 which genera-tes an output pulse train having pulses with a width approxi-mately equal to the width of the pulses generated by the l,VO
71. The multivibrator 73 functions to reduce the width of the pulses generated by the . lO circui-t 72 such that circuitry internal to an inverter driver 74 will not be overloaded. The output signal of the multivibrator 73 is applied to the inverter driver 74 to generate electric power on a line 75 at a fre-; quency of F(IN) which power is used to drive -the gob distributor and the gob feeder motors. Typically, -the inverter ~rlver 7~
functions as a three-phase, full-wave rectifier such that the frequency F(IN) is equal ko the frequency of the inverter driver .`' , ` ! ~ ~.` ' :

~: input signal divided by six. Thus, the gob distributor and the gob feeder motors receive a signal at a frequency F IIN) - F (LVO) /60. It should be noted that a buffer circuit (not shown) may be connected between the multivibrator 73 and the inverter driver 74 for interfacing logic voltage levels with the inverter driver control signal voltage levels.
The output of the LVO 71 is also connected to a second frequency dividing circuit 76 having a frequency division factor of P. The output oF the P circuit 76 is connecte~ to a mono-stablemultivibrator 77 which functions to "clean up" the outputpulse train of the . P circuit 76. Another monostable multi-vibrator 78 is provide~ to regulate the width of the clock pulses which are generated on a line 79 at a frequency F(OUT) =
F(LVO)/P. These clock pulses are supplied to the machine control circuit which utilizes the pulses as a reference for timing the machine cycle. An inverter (not shown) may be required between the multivibrators 77 and 78 to keep the LVO 71 output pulses and the clock pulses on the line 79 in phase since the multivibrator 78 typically triggers on the trailing edge of a "1" pulse. A buffer circuit ~not shown) can be connected to the line 79 to function as a signal level interface.
The clock pulse line 79 is also connected to an input of a third frequency dividing circuit 81 having a frequency division factor of six. The - 6 circuit 81 is connected to a fourth frequency dividing circuit 82 having a dividing factor ` of ten. The . 10 circuit 82 is connected to a fiEth frequency dividing circuit 83 haviny a dividing factor of six. Toyether, the circuits 81, 82 and 83 functlon to ~enerate a signal to a monostable multivibrator 84 at a frequency of F(OUrl')/360.
The multivibrator 84 function~ to "clean up" the outpu-t pulse "' . ,, traln of the . 6 circuit ~3. Another monostable multivibrator 85 is provided -to re~ulate -the pulse width of the reset pulses which are generated on a line 86 a-t a frequency of F(OUT)/360.
As previously discussed, the timing of the IS machine is typically based on a full cycle of 360~ which is represented by 360 clock pulses. There~ore, the reset pulses on the line 86 define the end and beginning of successive machine cycles~
An inverter (not shown) may be required between the multivibra-tors 84 and 85 to keep the clock pulses on the line 79 and the reset pulses on the line 86 in phase since the multivibrator 85 typically triggers on the trailing edge of a "1" pulse. A
buffer circuit (not shown) can be connected to the line 86 as a signal level interface.
The elements shown in Fig. 4 are commercially avail-able as integrated circuits or can be constructed from discrete components in accordance with well-known circuits. For ex-ample, a MC14566 industrial time base generator is capable of simultaneously providing a divide-by-10 counter, a divide-by-6 counter and an internal monostable multivibrator. Thus, one MC14566 can be used for the dividing circuits 72 and 81 an~
multivibrator 77 while another MC14566 can be used for the dividing circuits 82 and 83 and the multivibrator 89. The dividing circuit 76 can be a MC14569 programmable divide~by-N
counter. The multivibrator 73 can be a MC14538 precision mono-stable multivibrator while the mul-tivibrators 78 and 85 can be NE 555 timers which have been connected to function as monostable multivibrators. The "MC" circuit elements are manufactured by Motorola, Ins., Box 20912, Phoen:Lx, Arizona 85036 and the NE 555 tuner is manufactured by Signetics.
There is shown ln E'ig. 5 a table of timing values for 6~

various inver-ter drive frequencies and numbers of individual sections. Typically, the inverter drive output power frequency is variable from twenty to one hundred hertz. The drive motor 35 is connected to the gob feeder 33 through gearing to operate at a speed corresponding to forty-eight inverter frequency cycles for each gob formed and cut by the shears in an IS machine ha~ing six sections. Thus, the number of cuts/minute is deter-mined by multiplying the inverter frequency in hertz by sixty seconds/minute, and dividing by forty-eight cycles/cut. There are shown in the table of Fig. 5 values of inverter frequency.
The IS machine cycle rate or turns/minute is determined by dividing the cuts/minute value by the number of individual sections, in this example six. The gearing for the gob feeder is changed to accommodate different numbers of sections so as to maintain the same turns/minute value for a selected inverter frequency. As shown in the table, an eight section machine is geared for thirty-six cycles/cut and a ten section machine ` is geared for twenty-eight point eight cycles/cut.
he frequency of the output signal from the -timing 20 circuit 39 of Fig~ 3 must correspond to 360 pulses per machine cycle or turn. At an inverter frequency of twenty-four hertz, the turns/minute value is five thereby requiring a total of five times 360 pulses per minute which is a frequency of thirty ~ hertz. The value of N/M is one point two five. Therefore, `~ N can be five and M can be four in the hlock diagram of Fig.

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- The frequency of the clock pulses generate~ by the circuit of Fig. 4 must correspond to 360 pulses per machine cycle. If the inverter driver is yenerating three-phase power, - 30 the input pulse -train frequency is six times the output power . : . ,.

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frequency since six control pulses are requiredone for each half cycle. When the LVO 71 Erequency is at 1440 H~ the inver-ter driver is operating at 24 Hz and the turns/minute is five thereby requiring a total of five times 360 pulses per minute which is a frequency of 30 Hz. Thus, if F(OUT) is to equal 30 Hz, the value of P must be forty-eight since F~OUT) = F(LVO)/P =
1440~48 = 30 Hz.
In summary, the present invention concerns an elPctric - power and timing signals g~nerating means for an apparatus for ; 10 forming glassware. There is shown in Fig. 6 a block diagram of the electric power and timing signals generating means which diagram will be utilized to summarize the present invention.
The glassware forming apparatus includes means for forming gobs of molten glass and for distributing the gobs to an individual section glassware forming machine at a predetermined rate, means for generating electric power at a selected frequency and timing signals at a frequency proportional to the selected frequency, drive means responsive to the electric power for driving the means for forming and distributing gobs at the predetermined rate and a control circuit responsive to said timing signals for cyclically controlling each individual section machine in a predetermined time sequence of steps for forming glassware from the gobs.
The electric power and timing signals generating means includes an electric power and frequency reference signal source 91 and a means responsive to the frequency reference signal for generating the timing signals. The source 91 generates : electric power to a drive means g2 for the gob formlng and dis-tributing means and the frequency reference signal to a timing signals generating means. In one embodiment, see Fig. ~, the ~ 15 -`:

electric power and frequency reEerence siynal source includes an oscillator for generatiny the frequency reference signal, a frequency dividing means responsive to the frequency refer-ence signal for generating a control signal having a frequency ; equal to the reference signal frequency divided by a factor and an inverter drive means responsive to the control signal for generating the electric power at the selected frequency.
In another embodiment, see Fig. 3, the electric pow~r and fre-quency reference signal source includes an inverter drive means for generating the electric power at the selected frequency.
In this embodiment, the electric power signal also functions as the frequency reference signal which is supplied to the timing signals generating means.
The timing signals generating means includes a clock frequency dividing circuit 93 for generating clock pulses which are utilized by the glassware forming machine control circuit as a reference for timing the machine cycle which is typically defined by 360 clock pulses, although more or less pulses could be utilized. The timing means also includes a reset frequency ~` 20 dividing circuit 94 for generating reset pulses which typically ~` have a frequency of one pulse per machine cycle.
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In one embodimen-t, see Fig. 4, the timing signals generating means includes a first frequency dividing means res-ponsive to the frequency reference signal for generating a timing clock signal having a frequency equal to the reference signal frequency divlded by a first factor P. A second fre-quency dividing means is responsive to the timing clock signal for generating a timing reset signal having a frequency equal to the clock signal frequency divided by a second factor 360.

-~ 30 In another embodiment, see Fig. 3, the tlmJny signals :~ .

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, genera-ting means includes a first frequency dividin~ means res-ponsive to the electric power for generating a first input sig-nal having a frequency equal to the electri~ power frequen~y divided by a first factor M, second frequency dividiny means responsive to the timing signals for generating a second inpu-t signal having a frequency equal to the timing signals frequency divided by a second factor N and a phase locked loop responsive to the first and second input signals for generating -the timing signals having a frequency equal to -the electric power frequency divided by the first factor and multiplied by the second factor.
A third frequency dividing means is responslve -to the timing signals for generating timing rese~ signals having a frequency equal to the timing signals frequency divided by a third factor 360.
The circuits shown in Figs. 3 and 4 can also be com-bined to form a timing pulse generator where it is desired to operate the drive motor from a selected one of two or more dif-ferent power sources. For example, power for normal operation could be generated by an inverter and power ior emergency opera-tion could be generated by a varidyne. In Fig. 3, the line 51 would be connected to the power input terminal for the drive motor. The . M circuit 54 could be set to a value of one or could be replaced by a filter such -that the signal having the ~` frequency of F(IN)/M is of the same frequency as the frequency of the input power to the drive motor. The ~ N circuit 57 is set to divide by a factor of sixty such that -the output signal on the line 52 has a frequency of F~OUT) _ N . F~IN)/M ~ 60 . F~IN). The frequency dividing circuit 62 Ls no-t utilized.
In Fig. 4, the LVO 71, the . circuit 72, the mono-stable multivibrator 73 and -the inver-ter driver 74 are not utilized. The line 52 from the modified circuit of Eig. 3 is connected to the input of the . P circuit 76. If the factor P is set at forty-eight, the relationship between the frequency of the motor power F (IN) of Fig. 3, and the frequency of the clock pulses, F(OUT) of Fig. 4, will be F(OUT) = 60 F(IN)/~8 = 1.25 F(IN) to maintain the correct relationship between the speed of the drive motor and the timing of the IS machine.
The invention has been explained in its preferred embodiments. However, it must be understood that -the invention may ~e practiced otherwise than as specifically illustrated and described without departing from its spirit or scope. Al-though the power source has been described as an inverter drive, any source of AC single or poly-phase power can be utilized such as a motor/generator drive. If it is not desirable to consider the individual section machine as the zero phase refer-ence, means can be provided for changing the ratio o 1.25 be-tween the power source frequency and the clock pulse frequency momentarily to advance or retard the phase of the machine with , respect to the gob feeder or gob distributor. For example, ~0 in ~ig. 4 the counter 76 can be selectively programmed to vary from the normal divide by forty-eight upon the actuation of one or more switches to advance or retard the clock pulses and ~- reset pulses with respect to the phase of the electric power from the inverter driver.
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Claims (11)

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. An apparatus for forming glassware comprising:
means for forming gobs of molten glass and for distri-buting said gobs to an individual section glassware forming machine at a predetermined rate, electric means for generating electric power at a selected frequency;
frequency proportioning means connected to said electric power generating means for generating timing signals at a frequency proportional to said selected frequency;
electric drive means responsive to the electric power for driving said means for forming and distributing gobs at said predetermined rate; and a control circuit responsive to said timing signals for cyclically controlling each individual section of said in-dividual section machine in a predetermined time sequence of steps for forming glass from said gobs.

2. An apparatus according to claim 1 wherein a machine cycle is equal in duration to the time required for an individual section to form one article of glassware and said timing signals include a timing clock signal having a frequency of 360 pulses per machine cycle.

3. An apparatus according to claim 2 wherein said timing signals include a timing reset signal having a frequency of one pulse per machine cycle.

4. An apparatus according to claim 1 wherein said electric power and timing signals generating means includes an inverter drive means for generating said electric power at said selected frequency.

5. An apparatus according to claim 1 wherein said power and timing signals generating means includes means responsive to said electric power for generating said timing signals.

6. An apparatus according to claim 5 wherein said timing signals generating means includes a first frequency dividing means responsive to said electric power for generating a first input signal having a frequency equal to said electric power frequency divided by a first factor, a second frequency dividing means responsive to said timing signals for genera-ting a second input signal having a frequency equal to said timing signals frequency divided by a second factor, and a phase locked loop responsive to said first and second input signals for generating said timing signals having a frequency equal to said electric power frequency divided by said first factor and multiplied by said second factor.

7. An apparatus according to claim 6 wherein said timing means includes a third frequency dividing means respon-sive to said timing signals for generating timing reset signals having a frequency equal to said timing signals frequency divided by a third factor, said timing reset signals defining the time required for an individual section to form one article of glassware.

8. In an apparatus for forming glassware including gob feeding means for forming gobs of molten glass at a predeter-mined rate, means for distributing the gobs to an individual section glassware forming machine at the predetermined rate, the individual sections each having means for forming glassware from the gobs in a predetermined timed sequence of forming steps, an inverter for generating electric power at a predetermined frequency, electrical drive means responsive to the inverter power for driving the gob feeding means and the gob distri-buting means at the predetermined rate, a control circuit res-ponsive to timing signals for controlling the predetermined timed sequence of steps in each of the invididual sections and timing means for generating the timing signals, the timing means comprising:
means responsive to the inverter power for generating a first input signal having a frequency equal to the inverter power frequency divided by a first factor;
means responsive to the timing signals for generating a second input signal having a frequency equal to the timing signal frequency divided by a second factor; and means responsive to said first and second input sig-nals for generating the timing signals at a frequency equal to the inverter power frequency divided by said first factor and multiplied by said second factor.

9. A timing means according to claim 8 wherein said first factor is the integer four and said second factor is the integer five.

10. A timing means according to claim 8 including means responsive to the timing signals for generating reset signals having a frequency equal to the timing signals frequency divided by a third factor wherein the control circuit is res-ponsive to said reset signals for defining cycles of the in-dividual section machine.

11. A timing means according to claim 8 wherein said first and second input signal responsive means is a phase locked loop.