DE2166936A1 - Automatic control of original speed through photocopier - by measuring translucency of successive originals and delaying resulting signal - Google Patents

Abstract

The speed of a motor used to pass originals and copying material through the exposure zone of a copying machine is automatically controlled by deriving a speed-determining signal for each original while a preceding original is still in the exposure zone (e.g. by measuring the translucency of each original) storing each such signal until the preceding original has left the exposure zone, and then using the signal to control the motor speed as the origonal passes through the exposure zone and cancelling it from the store e.g. discharging a storage capacitor. For each original the control signal stored by a capacitor preferably comprises the signal from an array of photocells representing the greatest translucency of the original.

Description

K 2025 / Gbm 482 ¹ FP-Dr.Hn-mk April 13, 1971

description
to register

KALLE AKTIENGESELLSCHAFT Wiesbaden-Biebrieh

for a patent

Liclrfcpausmasdiine with a facility for automatic control of the throughput speed of the template and copy material.

The invention relates to a method and a device for automatically controlling the throughput speed of original and copy material in copiers, where the light transmission the originals is measured with a light-sensitive measuring unit, whereby the speed of the drive motor is controlled. **. '■ "■

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The device and method according to the invention are suitable both for copiers in which the copying material sheet is kept in stock, as well as for those devices in which the copy material is held in the form of an endless web on one or more supply rolls, of which it is depending on the length and width of the original to be copied can be automatically peeled off and cut.

Since the light transmittance of various originals and the sensitivity of copy materials in vary within wide limits, the throughput speed of the original and copy material must be in the area changed accordingly on the copier station. The change is made with conventional copiers the throughput speed by the operator by hand, which often leads to incorrect settings leads.

There are therefore devices have already been developed in which the transparency of the templates with

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a light-sensitive measuring unit is measured and based on the measured light transmission the speed of the drive motor is controlled (see. German Patent 925 751 and German Utility model 1 977 688).

From the German Auslegeschrift 1 522 790 is a ^

Device for automatic control of the throughput speed of original and copy material known, in which the light transmission of the original is measured with a CdS photoresistor, the resistance value of which is the potential of a capacitor which stores the potential so that the determined,

constant throughput speed is maintained. With this device can

but only entered a second template and your "

Light transmission can be measured when the first original is copied, which results in a loss of time Copy leads. ■

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The object of the present invention was to create a method and an apparatus which allow originals to be fed into a copier one after the other without losing time, due to their To store light transmission measured signals and to query the signals and for speed control of the drive motor when the originals reach the copier station.

In a further embodiment of the invention, methods and apparatus should be suitable for copying in which optionally the copying station is supplied from a sheet-shaped of several stock piles copying material or in which optionally deducted from one of a plurality of supply rolls, a copying material web, cut and fed to the printing station.

According to the invention, a method for automatically controlling the throughput speed of original and copy material in a copier is proposed, in which the light transmittance of the original is measured with at least one light-sensitive measuring unit, and the measuring unit sends a signal to the rotation based on the measured light transmittance.

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counting control of a drive motor is passed, which is characterized in that the Signals from at least two templates are stored that the signal belonging to a template to control the speed of the drive motor is queried shortly before this template reaches the copier station and that the queried signal is deleted.

According to the invention a device for the automatic control of the throughput speed of original is provided and copy material proposed in a copier, with at least one light-sensitive measuring unit for measuring the transparency of the original, which is characterized in that in the transport path of the original in front of the copier station

1.) at least one first switching element is located, which when actuated by the template

a) a first stepping mechanism switches and

b) for a certain time the light-sensitive measuring unit via this stepping mechanism connects to a memory, and

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2.) at least one second switching element is located, which when actuated by the template, a second Stepping mechanism switches, whereby the stored signal of the template via an amplifier is passed to a device for speed control of a drive motor, and that also in the transport path of the template at least one third switching element is located, which when actuated by the template a third Stepping mechanism switches, whereby the stored signal of this or the previous one Template is deleted.

According to the invention, a device is also proposed which is characterized in that that in the transport path of the template in front of the copying station 1.) there is at least one first holding element that when actuated by the template

a) a first stepping mechanism switches and

b) for a certain time the light-sensitive measuring unit via this stepping mechanism connects to a memory,

2.) at least one second switching element is located, which when actuated by the template

a) a second stepping mechanism switches, whereby the stored signal of the template

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via an amplifier to a device for controlling the speed of a drive motor is directed and

b) a third stepping mechanism switches, whereby the stored signal of the previous one Template is deleted.

The light-sensitive measuring unit for measuring the light transmittance of the original is preferably made from several light-sensitive elements as small as possible in order to increase the probability that the light transmission of an unmarked part of the original is measured. Off For the same reason it is advantageous to arrange the photosensitive elements so that they are both parallel and are offset from one another perpendicular to the direction of travel of the original. Is the photosensitive Measuring unit made up of several light-sensitive elements, there is a discriminator between light-sensitive elements Measuring unit and memory switched, the one of the signals measured at the light-sensitive elements selects which corresponds to the greatest light transmission. As light-sensitive elements, in known way poto resistors, photocells and the like. be used. -

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In copiers in which copy material webs with different properties are in stock are held and due to the scanned properties of the original one of the copy material webs is selected, a light-sensitive measuring unit is sufficient if the originals are always on the same guide rail of the input table introduced will. However, if the originals are placed on the right or left according to their width Introduced guide bar of the input table, are at least two light-sensitive measuring units available. The same applies to copiers in which several stacks of sheet-shaped copy material with different properties are kept in stock.

The switching elements, which are in the transport path of the template in front of the copying station, can be mechanical switches such. B. microswitches, photoelectric switches or inductive proximity switches. Are the templates introduced according to their width at the right or left guide rail of the feed table, the apparatus includes two first, second and third switching elements.

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Each stepping mechanism contains several pairs of contacts and a contact wiper that, as soon as a template actuates the switching element assigned to the respective stepping mechanism to the next pair of contacts wanders. To the signals obtained from two originals based on the measured light transmission The stepping units must save and query them later to control the speed of the drive motor each contain three pairs of contacts if the third switching element is behind the copier station and when this switching element is actuated by the template, preferably by its rear edge, that of this template associated stored value is deleted. If the third switching element is in front of the copier station and is activated when it is actuated the value belonging to the previous template is deleted by the leading edge of the template, so at least four contact pairs are present necessary. To store the signal of each additional template, the stepping mechanisms each have to have an additional one Contact pair included. If the memory consists of capacitors, the same applies to the number of capacitors. According to the invention the memory can contain a digital-analog-controlled flip-flop circuit instead of capacitors. This flip-flop circuit has

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The advantage over capacitors is that they keep the "stored signals" constant over a long period of time can hold.

When an original is inserted into the copier, it actuates a first switching element, the due to a brief electrical impulse, a first stepping mechanism switches as well as also connects the light-sensitive measuring unit to the memory via the first stepping mechanism. Since the connection is only made for a very short time by the pulse, it is advisable to use a Establish a delay unit for a certain longer time in order to -a constant final value in the memory to obtain. The time during which the connection is established must be such that at the highest throughput speed and with the shortest original format, the original during this time covers the light-sensitive measuring unit.

The stored signal of a template is queried when the second stepping mechanism is activated. Included is it transmitted via an amplifier, e.g. a transistor or an electron tube, to a device a controller, which controls the speed of the drive

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motors and thus regulates the throughput speed of the template. The deletion of a signal that occurs when the third stepping mechanism is switched, for example via a resistor.

In one embodiment of the invention The device in which the third switching element is in front of the copying station takes place when the second is actuated Switching element through a template, the query of the signal of this template and when the third switching element by the same template, the deletion of the signal of the previous template In the storage room. In another embodiment, in which the third switching element at any point, z. B. behind the copying station, a template deletes its stored when the third switching element is pressed Signal.

In a further, preferred embodiment with only two Switching elements takes place when the second switching element is actuated by a template and the query of the Signal of this template and at the same time the deletion of the signal of the previous template in Storage.

It is advantageous in the beam path of the light used to measure the light transmittance

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Eüilter to arrange that let that wave range of light become effective in which the copy material is sensitive to light. The filters can be in the beam path in front of the original, but preferably be arranged behind the original and in front of the light-sensitive measuring unit

In a further embodiment of the invention, a scattering film is attached between the template and the light source, to compensate for the widely differing scatter between templates with different transparency. By the scattering film will thus allow a better assignment of the measured light transmission values to the Throughput speeds enabled.

The light from the copying light source is preferably used to measure the light transmittance, as a result of which possible fluctuations in the light emission of the copying light source can also be detected. the Light guidance from the copier light source to the light-sensitive measuring unit can be done with mirrors, metal tubes or preferably UV light conducting optical fibers.

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According to the invention, if the memory contains capacitors and if the third switching element is in front the copier station, this with the contact pairs of the Stepper mechanisms switched as follows: each pair of contacts in the three stepper mechanisms is connected to a capacitor, each capacitor is connected to the same pair of contacts of the first and second stepping mechanism, however, with the next pair of contacts of the third Step switchgear. If, for example, the first capacitor of the memory is connected to the first contact pair of the connected to the first step switch mechanism, it is connected to the first pair of contacts of the second step switch mechanism and connected to the second pair of contacts of the third stepping mechanism. Is the third switching element behind the copying station, the capacitors are each with the same pair of contacts in all three stepping mechanisms tied together.

In the starting position, the contact wipers connect of the three stepping mechanisms in each of them the same pair of contacts, e.g. the first pair of contacts in each case. Should this synchronous circuit be used for a reason, e.g. interference pulses in the event of a power failure of the three stepping mechanisms are disturbed, a device is provided as below will be described in more detail to the synchronous circuit to restore by hand.

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According to the invention, the device can be calibrated in which for a number of templates with different Light transmittance determines the throughput speeds as well as the light transmittance values will. According to the values obtained, the zero crossing is indicated on the amplifier by means of a potentiometer and the gain is adjusted so that for each individual value of the light transmission the corresponding Voltage is applied to the controller, which in turn sets the correct speed of the drive motor and thus the results in the correct throughput speed for each original. The setting of gain and zero crossing of the amplifier is not only important for the calibration of the device, but also for adapting the device to the respective light sensitivity of the copying material used. In copiers, copier materials with very different light sensitivities are sometimes used. In addition, the photosensitivity of one and the same copy material changes with prolonged storage. In order to still get copies with the correct reason, the amplifier is

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Reinforcement and zero crossing adjusted accordingly. In this way, the reason for the pause can also be adapted to the respective template, depending on whether it is a pencil or ink drawing.

If necessary, the automatic control of the throughput speed switched off by a manually operated switching device and closed by hand regulating voltage can be applied to the regulator.

The invention will be explained in more detail with the aid of two exemplary embodiments and with the aid of the drawings. Show it

Figure 1 is a block diagram for the first embodiment

Figure 2 is a schematic plan view of the transport path of the originals before the copying station of the second embodiment \ (size of the templates and spacing of the switching elements are not shown to scale)

Figure 3 is a block diagram for the second embodiment

FIG. 4 shows a detailed circuit diagram of the memory and the step switching mechanisms for the second Embodiment

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Depending on whether an original 1 with the width a., An original 2 with the width a ₂ or an original with the width a, is entered in the copier, one of the copy material webs on the rollers 4, 5 and 6 Stock are held, selected (see Fig. 2). An original 1 with the width a., Is fed along the left guide bar (in the

™ drawing not entered) of the input table

guided, a template 2 of the width a- along the right guide bar and a template 3 of the width a, can be entered either left or right.

On its way to the copying station 7, an original 1, 2 or 3 passes at least one of the light-sensitive measuring units 8 and 8 ¹ , which each consist of the light-sensitive elements 8a to 8e or 8'a to 8'e. At this point, the original 1, 2 or 3 is irradiated with light from the copying light source, which falls through the filters 9a to 9e or 9'a to 9'e onto the light-sensitive elements 8a to 8e or 8 * a to 8'e that the translucence of the original

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Measure 1, 2 or 3 (see Pig. 1). Via the amplifiers 10a to 10e or 10 · a to 10 · e, the light-sensitive elements 8a to 8e and 8 ^! a to 8'e outgoing signals to the discriminator 11 or II ¹ . The discriminator 11 or 11 ^f selects the signal which corresponds to the greatest light permeability.

If the original 1 of width a ^ is entered into the copier, its light transmission is measured by the light-sensitive measuring unit 8, since the switch S, which establishes the connection between the light-sensitive measuring units 8 and 8 ^f and the rest of the measuring arrangement, is normally at the contact 12 is applied (see Figs. 1, 3 and 4). If, on the other hand, the original 2 of width a ~ is introduced into the copier, it actuates the switch S ₂ on its way, which, as long as it is touched by the original 2, switches the switch £ L to the Eontakt il ° via a switching unit 13 sets ο so that the light-sensitive keAunit 8 ° measures the light transmission. The same takes place if the original is 3 or more wide. & - at “Be ³ right

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Side of the input table is introduced. If it is inserted on the left side, the measuring unit 8 ¹ only measures when the original 3 is so wide that it actuates the switch Sp on its way.

In the transport path of the documents 1, 2 and 3, after the light-sensitive measuring units 8 and 8 ^{1, there are} two first switching elements S and Su. At least one of these switching elements S, and S ₁ , is actuated by the original 1, 2 or 3 on its way to the copying station 7 as soon as all of the light-sensitive elements 8a to 8e or 8'a to 8 ^f e of the light-sensitive measuring unit 8 or 8 'covers. As soon as at least one of the switching elements S ^ and S _{1 is} actuated, they trigger a brief electrical impulse via an electronic switch 14a, which in the first stepping mechanism 15a (for the P memory) moves the contact wiper 16a by one switching interval to the next pair of contacts a, b, c or d can wander »as well as closes the normally open switch Se for a certain time via a delay unit. This means that the step

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switching mechanism 15a, the connection between one of the light-sensitive measuring units 8 and 8 'and the memory 18 is established. Through the discriminator 11 or 11 ', the signal that the largest of the light-sensitive elements 8a to 8e or 8'a to 8 ^! e corresponds to measured light transmission in one of the capacitors C ^, Cp, C, and Cj. of the memory 18 is stored.

Behind the switching elements S, and S ₁ . are in the transport path of the templates 1, 2 and 3, two second switching elements S _c and S ™. At least one of these switching

D 7

elements Sg and S "is actuated by the original 1, 2 or 3 on its way to the copier station 7, whereby the switching elements Sg or S" trigger a brief electrical impulse via an electronic switch 14b, which in the second stepping mechanism 15b (for the query ) lets the contact wiper 16b wander by one switching interval to the next pair of contacts a ', b', c * or d ¹ . As a result, one of the capacitors C ₁ , C ₂ , C, and Cu is connected to the amplifier 19, namely that capacitor C ₁ ,

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C », C-. or Cj. connected to the amplifier 19, which is connected to the contact pair a ', b', ^c 'or d' reached by the contact wiper 16b. The signal stored in the relevant capacitor C ₁ , C ₂ , C, or C ^ is passed through the amplifier to the controller 20, which controls the speed of the drive motor 21 and thus the speed of the template 1, 2 or 3.

In the first exemplary embodiment (see Pig. I) there are finally two third switching elements Sn and S- (not shown in FIG. 2) in the transport path of the original 1, 2 or 3 in front of the copying station 7. At least one of these switching elements S ₀ and S_

ö 9

is operated by the template 1, 2 or 3, whereby the switching elements S ₀ or S _n via an electronic

8 9

see switch 1 ^ c trigger a brief electrical impulse, which in the third stepping mechanism 15c (for the deletion) lets the contact solenoid l6c wander by one switching interval to the next pair of contacts a ", b", c ", or d". This creates a connection between one of the capacitors C ₁ , Cp,

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C, or C ₁ . and the resistor 22 produced, namely that capacitor C ₁ , C ₂ , C, or C ₁ . connected to the resistor 22 and thus deleted its stored signal, which is connected to the contact pair a ", b", c "or d" reached by the contact wiper l6c.

The switching elements S, and S ₁ . can be connected either in series or in parallel. For the first case, they are normally closed (see Fig. 1, 3 or 4) and are opened when they are operated by a template 1, 2 or 3. By opening one or both switching elements S, and Sj. the pulse is triggered at the electronic switch l ^ a. If they are connected in parallel, they are normally open (not shown in the drawings) and are closed when they are operated by a template 1, 2 or 3. By closing one or both switching elements S ₁ and S 1. the pulse is triggered at the electronic switch 14a. The same applies to the switching elements Sg, S ₁ , and So, S _q .

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In the second exemplary embodiment (see FIGS. 3 and U) , the function of the third switching elements Sg and Sg is also taken over by the second switching elements S 1 and S 1. If a template 1, 2 or 3 activates one of the switching elements S, - and S ₇ and a brief electrical impulse is triggered via the electronic switch 14b, the contact wiper l6b in the second stepping mechanism l6b is switched by one switching interval to the next contact pair a ^f , b ', c ^f or d' and, as described above, the query of the stored signal of a template 1, 2 or 3 for speed control of the drive motor 21 is reached, as well as in the third stepping mechanism 15c the contact wiper 16c by a switching interval to the next contact pair a " , b ", c" or d "is switched and, as described above, the cancellation of the stored signal of the previous original 1, 2 or 3 is achieved via the resistor 22.

Each contact pair a to d, a 'to d ¹ and a "to d" in the three step switchgear 15a, 15b and 15c is connected to one of the capacitors CL, C ₂ , C, and C ₁ ^ . Each capacitor CL, C ₂ , C, and C ₁ . is with

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connected to the same pair of contacts a to d and a 'to d' of the first and second stepping mechanism 15a and 15b, for example CL with a and a 'or C ₂ with b and b', but with the next pair of contacts b "to a" des third stepping mechanism 15c, for example C ₁ with b "or C ₂ with c" (see FIG. 4).

The contact wipers 16a, 16b and 16c must be switched synchronously in the starting position. If the contact wiper 16a in the stepping mechanism 15a connects the contact pair a, for example, the contact wiper 16b in the stepping mechanism 15b must connect the contact pair a ¹ and the contact wiper 16c in the stepping mechanism 15c must connect the contact pair a ". If the synchronous switching of the three stepping mechanisms 15a, 15b and 15c, for example, is disturbed by noise pulses after a power failure, it can be restored manually. to this end, in each of the three stepping mechanisms 15a, 15b and 15c each one of the contact pairs a to D, a ¹ to d ¹ and a "to d" with each connected to a lamp L ₁ , L ₂ or L. The contacts that are connected to the lamps must be the same in the three stepping units 15a, 15b and 15c.

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In FIG. 4, for example, the contacts d, d 'and d "are connected to the lamps L ₁ , L_ and L, respectively. There is also a manually operated switching device S ₁₀ which, when actuated, firstly establishes a connection between the light-sensitive measuring units 8 and 8 'and the stepping mechanism 15a prevents secondly the capacitors C ₁ to C _1. Of the memory 18 short-circuits, so that at each contact pair a to d, a' to d 'and a "to d" of the three stepping mechanisms 15a, 15b and 15c one pole of a voltage source U is and thirdly the lamps L, L ρ and L, each connected to the other pole of the voltage source U. With the help of the manually operated setting buttons S ₁₁ , S ₁₂ and S ₁ , the contact wiper 16a, 16b or 16c can be adjusted individually via the electronic switches 14a, 14d or Ike If, for example, the contact wiper 16a is adjusted with the aid of the setting _{button S 11} via the electronic switch 14a, the circuit is closed and the lamp L ₁ lights up on, as soon as the contact wiper 16a has reached the contact pair d. The same applies to the contact wiper 16b and 16c. The three step

Switching mechanisms are switched synchronously as soon as all three lamps L ₁ , L «and L, light up.

The method of puncturing is to be explained on the basis of the second exemplary embodiment when two originals are entered into the copier one after the other. In the in Pig. In the position shown in H, the drive motor 21 runs at the speed which corresponds to the signal stored _{in the capacitor C 1.} The signal belongs to the original that entered the copier station 7 last. The capacitor Cj. is discharged through resistor 22. If, for example, the original 1 has been introduced into the copier, it runs over the light-sensitive measuring unit 8. When the original 1 reaches the switching element S ,, a brief pulse is triggered by which the contact wiper 16a switches from the contact pair a to the contact pair b and the Switch S, - is closed for a certain time. As a result, the light-sensitive measuring unit 8 is connected to the memory 18 via the stepping mechanism 15a, specifically to the capacitor C _{2 of} the memory 18.

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Corresponding to that in the light-sensitive measuring unit 8 measured light transmission of the original 1, the capacitor C "is charged.

Meanwhile, a second original, Original 2, is being fed into the copier. It runs over the light-sensitive measuring unit 8 'and actuates the switch S ₂ . As already described above, the switch S ₁ normally applied to the contact 12 is thereby lifted from this contact and applied to the contact 12. If the template 2 reaches the switching element S ₁ ^, the contact wiper 16a moves from the contact pair b to the contact pair c and at the same time the switch S, - is closed for a certain time and the capacitor C is charged according to the transparency of the template 2. It is not possible to enter a third template because the capacitor C ^ is grounded via the contact wiper I6c. A fifth capacitor and a fifth pair of contacts in each of the three stepping units 15a, 15b and 15c would have to be present for the input and storage of a third template.

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If the template 1 has reached the switching element Sg, a brief pulse is triggered which switches both the contact wiper l6b in the stepping mechanism 15b from the contact pair a ¹ to ^{the contact pair b 1} and the contact wiper 16c in the stepping mechanism 15c from the contact pair a "to the contact pair b" switches. By switching the contact wiper 16b from a ¹ to b ', the signal of the template 1 stored in the capacitor Cp is placed via the amplifier 19 and the controller 20 and the speed of the drive motor 21 is regulated. Original 1 and the copy material that was pulled from the supply roll 4 selected by it and cut according to its length (not shown in the drawings), run congruently into the copying station 7 with the throughput speed corresponding to the transparency of the original 1. By switching the contact wiper 16c from a "to b", the capacitor C. is discharged via the resistor 22 and is thus free to store the signal of a new template, which can now be entered.

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Original 2 is still between the input of the device and copier station 7 Switching element S ", a pulse is triggered that moves the contact wiper 16b from the contact pair b 'to the contact pair c ', and the contact wiper 16c switches from contact pair b "to contact pair c". The signal the template 2 is interrogated by the capacitor C, whereby they enter the copier station at the speed that corresponds to their light transmission 7 arrives, and the signal of the template 1 stored in the capacitor Cp is deleted, the signal for storage the signal of another original is free. As soon as the template 2 is released the switch Sp has, the switch S. is back in its normal position brought in which it rests on contact 12.

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Claims (1)

Elimination from λ «May 28, 19 76 P 21 19 373.7-51 * ⁰ ^ * WLK-DI.Sb-rw K 202 5-1 Claims l) Blueprint machine with a photosensitive Measuring unit for measuring the transparency of the original and corresponding control of the transport speed i a chop drive, characterized in that the light-sensitive Measuring unit (8,8 ') made up of several light-sensitive Elements (8a to 8e, 8'a to 8'e), which are both parallel and perpendicular to the direction of travel of the original (1, 2, 3) are arranged offset from one another. 2. Blueprint machine with a photosensitive
Measuring unit for measuring the light transmittance of the original and corresponding control of the transport speed of a traction drive, characterized in that a discriminator (11, 11 ') is connected between the light-sensitive measuring unit (8, 8') and memory (18) to select the
Signal that has the greatest light transmission of the original
(1,2,3) corresponds. 3. Blueprint machine with a photosensitive
Measuring unit for measuring the light transmittance of the original and corresponding control of the transport speed of a material drive, characterized in that in the beam path the for measuring the light transmittance of the original 609885/0412 Elimination from "% May 28, 1976 P 21 19 373.7-51 * ⁵ * * WLK-DI.Sb-rw K 2025-1 (1, 2, 3) used light filters (9a to 9e, 9'a to 9'e) are arranged. H. Blueprint machine with a light-sensitive measuring unit for measuring the light transmittance of the original and corresponding control of the transport speed of a traction drive, characterized in that a stiffening sheet is attached between the light source used to measure the light transmittance and the original (1, 2, 3). 5. Blueprint machine with a light-sensitive measuring unit for measuring the transparency of the original and corresponding control of the transport speed of a chopped material drive, characterized in that the for The light source used to measure the light transmission is the copy light source. 6. Blueprint machine with a photosensitive Measuring unit for measuring the transparency of the original and corresponding control of the transport speed a chop drive, characterized in that UV light conductive optical fibers are provided for guiding light. 609885/0412 \ 5ι blank page