GB2027955A – Electronic interval timer
– Google Patents
GB2027955A – Electronic interval timer
– Google Patents
Electronic interval timer
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Info
Publication number
GB2027955A
GB2027955A
GB7926960A
GB7926960A
GB2027955A
GB 2027955 A
GB2027955 A
GB 2027955A
GB 7926960 A
GB7926960 A
GB 7926960A
GB 7926960 A
GB7926960 A
GB 7926960A
GB 2027955 A
GB2027955 A
GB 2027955A
Authority
GB
United Kingdom
Prior art keywords
time
units
unit
digits
tens
Prior art date
1978-08-11
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
GB7926960A
Other versions
GB2027955B
(en
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Diehl Verwaltungs Stiftung
Original Assignee
Diehl GmbH and Co
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
1978-08-11
Filing date
1979-08-02
Publication date
1980-02-27
1979-08-02
Application filed by Diehl GmbH and Co
filed
Critical
Diehl GmbH and Co
1980-02-27
Publication of GB2027955A
publication
Critical
patent/GB2027955A/en
1982-12-22
Application granted
granted
Critical
1982-12-22
Publication of GB2027955B
publication
Critical
patent/GB2027955B/en
Status
Expired
legal-status
Critical
Current
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Classifications
G—PHYSICS
G04—HOROLOGY
G04G—ELECTRONIC TIME-PIECES
G04G5/00—Setting, i.e. correcting or changing, the time-indication
G04G5/04—Setting, i.e. correcting or changing, the time-indication by setting each of the displayed values, e.g. date, hour, independently
G04G5/043—Setting, i.e. correcting or changing, the time-indication by setting each of the displayed values, e.g. date, hour, independently using commutating devices for selecting the value, e.g. hours, minutes, seconds, to be corrected
G04G5/045—Setting, i.e. correcting or changing, the time-indication by setting each of the displayed values, e.g. date, hour, independently using commutating devices for selecting the value, e.g. hours, minutes, seconds, to be corrected using a sequential electronic commutator
G—PHYSICS
G04—HOROLOGY
G04F—TIME-INTERVAL MEASURING
G04F1/00—Apparatus which can be set and started to measure-off predetermined or adjustably-fixed time intervals without driving mechanisms, e.g. egg timers
G04F1/005—Apparatus which can be set and started to measure-off predetermined or adjustably-fixed time intervals without driving mechanisms, e.g. egg timers using electronic timing, e.g. counting means
Description
1 GB 2 027 955 A 1
SPECIFICATION
A method of and circuit for adjusting an electronic digital display The invention relates to a method of adjusting an electronic digital display of a desired period of time, more 5 especially the duration-of-cooking of a microwave oven, wherein the adjustment is undertaken by a series of -stepping impulses. The invention also relates to a circuit for carrying out the method.
An electromechanical adjusting device for an electronic digital display is described in German Patent Application No. P 26 28 794.5 and in British Patent Specification No. 1510744. By means of a manually-actuatable impulse generator, stepping impulses for adjusting the electronic digital display are 10 produced. The input speed is, in this respect, restricted. It is therefore proposed, in German Patent Application No. P 27 26 383, to increase the frequency of the stepping impulses as from a specific input frequency in an over-proportional manner. The display can thus be adjusted rapidly even over several hours.
A method of producing and processing stepping impulses for the adjustment or correction of an electronic digital display is proposed in German Patent Application No. P 28 28 285. 1. In this respect, a microprocessor 15 can be connected between an electromechanical impulse generator and the display. An increase in the possible input speed is achieved.
If hours and minutes are to be able to be adjusted, then the microprocessor has to process 24 x 60 = 1,440 adjusting possibilities for the adjustment.
In the case of equipment in which a desired period of time for a working process is to be adjusted, for example in the case of ovens, more especially microwave ovens, it is not of crucial importance that in the entire possible time range the desired period of time is set exactly down to the last place. Thus, in the case of microwave ovens, for example in the case of short desired periods of time, an adjustability accurate to seconds is necessary. In the case of longer desired periods of time, an adjustment which is accurate to minutes is sufficient.
A task of the invention is to provide a method, of the kind mentioned at the beginning hereof, by which, with a small or reduced number of stepping impulses, desired periods of times can be set with sufficient accuracy.
According to the invention, there is provided a method of adjusting an electronic digital display of a desired period of time wherein the adjustment is undertaken by a series of stepping impulses, characterised 30 in that the span of the maxim u m adjustable desired period of time is divided into a plurality of time ranges and in that as a result of the stepping impulses, in a first time range the units digits and the tens digits of a first unit of time are stepped on and in a second time range the tens digits of the first unit of time and the units digits of a second unit of time superior to the first unit of time are stepped on and in a third time range the units digits and the tens digits of the superior second unit of time are stepped on. Thus, in each time range an adjustment accurate to two places is possible. A third or further place is not stepped by stepping impulses. The aforesaid span of the maximum adjustable desired period of time may if desired be divided into more than three time ranges, with, in the further time range or time ranges beyond the third time range, units and/or tens digits of a further superior unit of time, or of further superior units of time, being stepped on.
If the first unit of time is seconds and the superior second unit of time is minutes, then the first time range can lie between 1 sec and 59 sec, the second time range can lie between 1 min, 10 sec and 9 min, 50 sec, and the third time range can lie between 10 min and 99 min. It is apparentthat, in this respect, altogether only 204 adjusting possibilities have to be processed. In contrast, if the units digits and the tens digits of the first unit of time had to be stepped-on constantly also in the second and third time ranges, 6000 adjusting possibilities 45 would have to be processed. The invention brings the advantage that for the adjustment in comparison with the prior art, only a comparatively few stepping impulses are necessary, so that on the one hand the adjustment can be undertaken rapidly and on the other hand the processing capacity of a circuit producing the stepping impulses from an electromechanical impulse generator can be small.
Preferably, when the units digit of the superior second unit of time is other than zero and the tens digit of 50 this unit of time is zero, the tens digits of the first unit of time are stepped on as a result of the stepping impulses, and, when the tens digit of the superior second unit of time is other than zero, the units digits of this second unit of time are stepped on as a result of the stepping impulses.
Preferably, in instances where the adjustment of the diaplay is controlled by timing impulses, when the units digit of the superior second unit of time is other than zero, the timing impulses for the units digits of the 55 first unit of time are blocked and, when the tens digits of the superior second unit of time are other than zero, the timing impulses forthe units digits and the tens digits of the first unit of time are blocked. In this way it can be avoided that, in the second time range, units digits of the first unit of time and, in the third time range, units digits and tens digits of the first unit of time are stepped-on, in a manner confusing the user, simultaneously with digits at higher places.
Also, according to the invention, there is provided a circuit, for carrying out a method in accordance with the invention, having a respective counter/display unit or device for each place, in which respect in each case a carry signal of the counter of one display unit or device is conducted to the counter of the next-higher display or device, characterised in that the stepping impulses are present at each of the counter/display units or devices and in that, when the counter of a display unit or device superior to the two lowest-ranking display 65 2 GB 2 027 955 A 2 units or devices is at a value other than zero, an enabling signal derived thereform is conducted, instead of the carry signal, to the counter of the display unit or device next lower in rank to this superior display unit or device.
Further, according to the invention, there is provided a method of adjusting an electronic digital display of a desired period of time, wherein the adjustment is undertaken by stepping impulses, characterised in that 5 the span of the maximum adjustable desired period of time is divided into a plurality of time ranges and in that in each time range digits of the display are stepped on at only two places of the display, said two places being consecutive places, and the two places at which digits are stepped on in the or each further time range subsequent to the first of the time ranges consisting of the higher of the two places at which digits are stepped on in the time range next preceding the, or the respective, further time range, and a place higher than and consecutive to said higher place of said next preceding time range.
The accompanying drawing, which shows, by way of example, means for carrying out a method in accordance with the invention, is a block wiring diagram of an adjusting circuit for display means of a microwave oven.
Referring to the drawings, a manually-actuatable electromechanical impulse generator 1 is operable to 15 produce a series of impulses which are evaluated in an impulse evaluation circuit 2, which may for example comprise a microprocessor 2. Such impulse evaluation circuits are known for example from documents mentioned at the beginning hereof.
A stepping pulse train which corresponds to the respective adjustment of the impulse generator 1 is present at an output 3 of the impulse evaluation circuit 2. A timing signal occurs at an output 4 of this 20 impulse evaluation circuit.
The output 3 is connected to the counting inputs of four forwards/backwards counters 5,6,7 and 8. The output 4 is connected via an AND gate 9 to thetiming input of the counter 5, via an AND gate 10 to the timing input of the counter 6 and directly to the timing inputs of the counters 7 and 8.
One-place digital display units 11, 12,13 and 14 are associated one with each of the counters.
The display unit 11 serves to indicate the units seconds 0 to 9, the display unit 12 the tens seconds 0 to 5, the display unit 13 the units minutes 0 to 9 and the display unit 14 the tens minutes 0 to 9. A carry output of the counter 5 is connected by way of an OR gate 15 to an enabling input of the counter 6. The carry output thereof is connected by way of an OR gate to an enabling input of the counter 7. The carry output of the counter 7 is connected directly to an enabling input of the counter 8.
The counter state of the counters 7 and 8 is monitored by means of respective zero discriminators, 17 or 18 respectively. The output of the discriminator 17 is connected by way of an inverter 19 and an OR gate 20 to the OR gate 15 and to a negated input of the AND gate 9. The output of the discriminator 18 is connected by way of an inverter 21 on the one hand to the OR gate 20 and on the other hand to the OR gate 16 and a negated input of the AND gate 10.
Upon actuation of the impulse generator 1 there occur at the output 3 stepping impulses which correspond, in their number, to the actuation. The timing at the output 4 is independent thereof. If one starts with all the counters being set to zero, then at the start of the actuation of the impulse generator 1 initially the counter 5 steps on by one step upon each stepping impulse. The other counters 6,7 and 8 are initially still blocked at their enabling inputs. Accordingly, the display units 12,13 and 14 are at zero and the display unit 40 11 is stepped through from 0 to 9. If the counter 5, or more specifically the display unit 11, is at 9, then by way of the carry output the counter 6 is enabled. Upon the next stepping impulse, the counter 5 is set to 0 and the counter 6 is set to 1. Further stepping impulses step on in turn, as far as the carry, the counter 5. These processes are repeated until the counter 6 is at 5. In this first time range there is thus effected an adjustment which is stepped according to seconds:
min sec 00 01 50 00 02 55 00 59 60 Upon the next stepping impulse, the counters 5 and 6 are set to 0 and the counter 7 is set to 1. By way of the discriminator 17 and the inverter 19, as well as the OR gate 20, the AND gate 9 is blocked, so that the timing input of the counter 5 is blocked and a further stepping impulse cannot step this any further. At the same time the output signal of the discriminator 17 lies at the OR gate 15, so that the enabling input of the counter 6 allows, independently of the carry output of the counter 5, a stepping-on of the counter 6. Upon 65 4 A 1 3 GB 2 027 955 A 3 further stepping impulses, thus the counter 6 is directly stepped on. Its carry ouput accordingly steps the counter 7 on. In this second time range there is thus effected the following adjustment:
min sec 5 01 00 01 10 01 20 10 15 09 50 Upon the stepping impulse following on the adjustment 9 min: 50 sec, the counters 6 and 7 are set to 0 20 and the counter 8 is set to 1. In this way the discriminator 18 responds and blocks, byway of the inverter 21 and the AND gate 10, the timing input of the counter 6. Byway of the OR gate 20 and theAND gate 9the timing input of the counter 5 is furthermore kept blocked. Moreover, the output signal of the discriminator 18 switches free, by way of the inverter 21 and the OR gate 16, the counter 7 at its enabling input. Further 25stepping impulses act now directly on the counter 7, in which respect in each case upon a carry signal at the 25 counter 7 the counter 8 is stepped on by one further digit. In this third time range the following adjustment is effected.
min 11 12 98 99 sec 00 00 00 00 00 As a whole thus the adjustment of the counters, more specifically the display units, in the three time ranges is possible with 204 stepping impulses. The counters, more specifically the display units, can be adjusted both forwards and backwards. Thus, with a comparatively few impulses, an adjustability which is 50accurate to two places is afforded to a large time coverage. In accordance with the respective adjustment, 50 carried out by means of the impulse generator 1, of the desired period of time, there is controlled, via the impulse evaluation circuit 2, the cooking time of a microwave oven (not shown in more detail). Starting from the selected adjusted setting, the impulse evaluation circuit 2 with commencement of the cooking time counts backwards the counters 5,6,7 and 8 in seconds rhythm without range switch-over, in which respect 55the course of the cooking time can be followed at the display units 11, 12,13 and 14. If all the counters are 55 counted backwards to zero, then the microwave oven is switched off.
The method described can be used also in other time coverages, for example in a minutes and hours coverage, or in a largertime coverage, for example in a seconds, minutes and hours coverage.
Claims (12)
60CLAIMS
1. A method of adjusting an electronic digital display of a desired period of time wherein the adjustment is undertaken by a series of stepping impulses, characterised in that the span of the maximum adjustable desired period of time is divided into a plurality of time ranges and in that as a result of the stepping 65impulses, in a first time range the units digits and the tens digits of a first unit of time are stepped on and in a 65 4 GB 2 027 955 A 4 second time range the tens digits of the first unit of time and the units digits of a second unit of time superior to the first unit of time are stepped on and in a third time range the units digits and the tens digits of the superior second unit of time are stepped on.
2. A method of adjusting an electronic digital display of a desired period of time, wherein the adjustment is undertaken by stepping impulses, characterised in that the span of the maximum adjustable desired period of time is divided into a plurality of time ranges and in that in each time range digits of the display are stepped on at only two places of the display, said two places being consecutive places, and the two places at which digits are stepped on in the or each further time range subsequent to the first of the time ranges consisting of the higher of the two places at which digits are stepped on in the time range next preceding the, orthe respective, further time range, and a place higher than and consecutive to said higher place of said 10 next preceding time range.
3. A method as claimed in Claim 1, wherein said span is divided into more than three time ranges, and wherein in the further time range or time ranges beyond the third time range units and/or tens digits of a further superior unit of time, or of further superior units of time, are stepped on.
4. A method as claimed in Claim 1 or 3, wherein the desired period of time is the cluration-of-cooking time of a microwave oven.
5. A method as claimed in Claim 1, 3 or 4, wherein when the units digit of the superior second unit of time is other than zero and the tens digit of this unit of time is zero, the tens digits of the first unit of time are stepped on as a result of the stepping impulses, and wherein, when the tens digit of the superior second unit of time is other than zero, the units digits of this unit of time are stepped on as a result of the stepping 20 impulses.
6. A method as claimed in anyone of Claims 1, 3,4 and 5, wherein the adjustment of the display is controlled by timing impulses, and wherein, when the units digit of the superior second unit of time unit is other than zero, the timing impulses for the units digits of the first unit of time are blocked and, when the tens digit of the superior second unit of time is other than zero, the timing impulses for the units digits and for the 25 tens digits of the first unit of time are blocked.
7. A circuit, for carrying out a method as claimed in anyone of the preceding claims, having a respective counter/display unit or device for each place, in which respect in each case a carry signal of th6 counter of one display unit or device is conducted to the counter of the next- higher display unit or device, characterised in that the stepping impulses are present at each of the counter/display units or devices and in that, when the 30 counter of a display unit or device superior to the two lowest-ranking display units or devices is at a value other than zero, an enabling signal derived therefrom is conducted, instead of the carry signal, to the counter of the display unit or device next lower in rank to this superior display unit or device.
8. A circuit as claimed in Claim 7, wherein the enabling signal blocks a timing input of the or each display unit or device which is below in rank to the display unit or device to which the enabling signal is applied 35 instead of the carry signal.
9. A circuit as claimed in Claim 7 or 8 having display units or devices for units seconds, tens seconds, units minutes and tens minutes, wherein AND gates are connected to timing inputs of counters associated with the units seconds and the tens seconds, and the AND gate associated with the counter associated with the units seconds is blockable (a) by a discriminator which is connected subsequent to the counter associated with the units minutes or (b), by way of an OR gate, by a discriminator connected subsequent to a counter associated with the tens minutes, and respective OR gates are connected subsequent to the carry outputs of the counters associated with the units seconds and with the tens seconds, the output of the discriminator associated with the counter associated with the units minutes being connected to the OR gate connected subsequent to the counter associated with the units seconds and the output of the discrimintor 45 associated with the counter associated with the tens minutes being connected to the other OR gate.
10. A microwave oven provided with a circuit constructed and arranged in accordance with anyone of Claims 7 to 9.
11. A method of adjusting an electronic digitial display, substantially as herein described with reference to the accompanying drawing.
12. A circuit for adjusting an electronic digital display, substantially as herein described with reference to the accompanying drawing.
Printed for Her Majesty’s Stationery Office, by Croydon Printing Company Limited, Croydon Surrey, 1980.
Published by the Patent Office, 25 Southampton Buildings, London, WC2A lAY, from which copies may be obtained.
4 i z A A 0
GB7926960A
1978-08-11
1979-08-02
Electronic interval timer
Expired
GB2027955B
(en)
Applications Claiming Priority (1)
Application Number
Priority Date
Filing Date
Title
DE2835200A
DE2835200C3
(en)
1978-08-11
1978-08-11
Method and circuit for setting an electronic digital display of a target duration
Publications (2)
Publication Number
Publication Date
GB2027955A
true
GB2027955A
(en)
1980-02-27
GB2027955B
GB2027955B
(en)
1982-12-22
Family
ID=6046771
Family Applications (1)
Application Number
Title
Priority Date
Filing Date
GB7926960A
Expired
GB2027955B
(en)
1978-08-11
1979-08-02
Electronic interval timer
Country Status (9)
Country
Link
US
(1)
US4321697A
(en)
JP
(1)
JPS5527991A
(en)
DE
(1)
DE2835200C3
(en)
DK
(1)
DK155251C
(en)
ES
(1)
ES482315A1
(en)
FR
(1)
FR2433196A1
(en)
GB
(1)
GB2027955B
(en)
IT
(1)
IT1122354B
(en)
SE
(1)
SE444993B
(en)
Cited By (1)
* Cited by examiner, † Cited by third party
Publication number
Priority date
Publication date
Assignee
Title
CH684624GA3
(en)
*
1991-01-25
1994-11-15
Electrolux Ag
Electronic timeswitch for oven controllers
Families Citing this family (4)
* Cited by examiner, † Cited by third party
Publication number
Priority date
Publication date
Assignee
Title
DE3003847A1
(en)
*
1979-02-05
1980-08-07
Turnright Controls
TIMER SWITCHING
US4504716A
(en)
*
1981-01-13
1985-03-12
Matsushita Electric Industrial Co., Ltd.
Electronic digital timer
JPS62134555U
(en)
*
1986-02-17
1987-08-25
DE3704192A1
(en)
*
1987-02-11
1988-08-25
Otto Nockemann
FILLED PASTA BAG
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Assignee
Title
DE6920097U
(en)
*
1969-05-16
1970-03-19
Schleicher Relais
ADJUSTING KNOB FOR A TIME RELAY OPERATING WITH DIFFERENT TIME VALUES AND DIFFERENT TIME RANGES
DE1959829A1
(en)
*
1969-11-24
1972-03-16
Schleicher Relais
Electromechanical time relay
JPS5638917B1
(en)
*
1971-06-23
1981-09-09
US3762152A
(en)
*
1971-12-08
1973-10-02
Bunker Ramo
Reset system for digital electronic timepiece
US4107915A
(en)
*
1972-12-28
1978-08-22
Citizen Watch Co., Ltd
Electronic timepiece
US3988886A
(en)
*
1973-08-14
1976-11-02
Casio Computer Co., Ltd.
Time setting device for an electronic watch
US3877276A
(en)
*
1973-12-28
1975-04-15
Mesta Machine Co
Mill roll changing system including a cantilevered roll assembly
JPS50120668A
(en)
*
1974-03-07
1975-09-22
US4176516A
(en)
*
1975-06-13
1979-12-04
Nippon Electric Co., Ltd.
Arrangement for putting an electronic timepiece right with minute indication advanced at first
DE2628794C3
(en)
*
1976-06-26
1985-07-18
Diehl GmbH & Co, 8500 Nürnberg
Setting device for an electronic digital display
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(en)
*
1976-11-22
1979-03-13
Zenith Radio Corporation
Electronic time-keeping system with electro-mechanically-driven analog display and electrical integral hour reset feature
1978
1978-08-11
DE
DE2835200A
patent/DE2835200C3/en
not_active
Expired
1979
1979-06-28
SE
SE7905676A
patent/SE444993B/en
not_active
IP Right Cessation
1979-07-09
ES
ES482315A
patent/ES482315A1/en
not_active
Expired
1979-07-11
DK
DK291379A
patent/DK155251C/en
not_active
IP Right Cessation
1979-07-11
JP
JP8699879A
patent/JPS5527991A/en
active
Granted
1979-07-20
FR
FR7918798A
patent/FR2433196A1/en
active
Granted
1979-07-25
US
US06/060,397
patent/US4321697A/en
not_active
Expired – Lifetime
1979-07-26
IT
IT24676/79A
patent/IT1122354B/en
active
1979-08-02
GB
GB7926960A
patent/GB2027955B/en
not_active
Expired
Cited By (1)
* Cited by examiner, † Cited by third party
Publication number
Priority date
Publication date
Assignee
Title
CH684624GA3
(en)
*
1991-01-25
1994-11-15
Electrolux Ag
Electronic timeswitch for oven controllers
Also Published As
Publication number
Publication date
JPS5527991A
(en)
1980-02-28
DK155251B
(en)
1989-03-13
US4321697A
(en)
1982-03-23
DE2835200A1
(en)
1980-02-14
DE2835200B2
(en)
1980-07-17
DK291379A
(en)
1980-02-12
FR2433196A1
(en)
1980-03-07
IT1122354B
(en)
1986-04-23
DK155251C
(en)
1989-07-24
GB2027955B
(en)
1982-12-22
FR2433196B1
(en)
1985-01-18
SE7905676L
(en)
1980-02-12
SE444993B
(en)
1986-05-20
JPS6147391B2
(en)
1986-10-18
IT7924676D0
(en)
1979-07-26
ES482315A1
(en)
1980-03-01
DE2835200C3
(en)
1984-06-28
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Legal Events
Date
Code
Title
Description
1997-03-26
PCNP
Patent ceased through non-payment of renewal fee
Effective date:
19960802
