DE2912755C2 - Circuit arrangement for controlling the movement of an implement, in particular a dental treatment chair - Google Patents

Description

The invention relates to a circuit arrangement for controlling the movement of an implement, in particular a dental treatment chair, according to the preamble of claim 1.

Such a circuit arrangement is from the DE-AS 27 36 276 known. The actual information corresponding to the actual position of the dental treatment chair is transferred to the drive motor with the aid of a the movement device coupled clock generated and depending on the direction of rotation of the drive motor counting up or down. A read-only memory is provided for outputting the target information. A connected to the counter and the read-only memory controls the drive motor via a comparator Amplifier switches on when there is a difference depending on its sign in one or the other direction of rotation and switches it off when the count remains the same. In the case of the known circuit arrangement, only a relatively cumbersome programming of a new one is required Code combinations defining setting items in the read-only memory possible, which represent the target information. It is first necessary to move the movement device into the desired setting position brought by hand control. Then, by pressing a prop / ammlertaste, the then programmable memory is switched to via the comparator Prepared to accept the new values of the setting position. Only then will you press one of the The new code combination is inscribed in the key corresponding to the desired setting position. Furthermore can disadvantageously, the counter counts incorrectly due to glitches, resulting in an incorrect setting of the dental treatment chair into the desired setting position.

In another program-controlled dental treatment chair (DE-PS 21 19 837) each manually adjustable setting position by means of a transmission device, such as a punch card punch, on a storage medium, such as a punch card, which is then consulted and used when necessary to adjust the treatment chair. This has the disadvantage of laborious and time-consuming searching the respective punch card from a card index, whereby otherwise there is a risk of confusion.

With a different control circuit (DE-PS 25 54 059)

to adjust the position of a dental treatment chair, voltage generators for actual information and Target information used, where target information is contained in a memory and can be overwritten. An actuator can be controlled by a comparator or by switches. The voltage generator for the target information is formed by a resistor network with individual resistors that depend on the output signal a counter or a shift register can be selectively connected between two voltage levels and the output signal of which is fed to the comparator, dsr via a voltage selector and signal lines is connected to the actuator. This known control circuit works analog and is already "therefore prone to failure and difficult to adjust.

In another known dental treatment chair (DE-OS 27 26 100) is for an actuator an electric drive is provided for each movement coordinate. Position detectors are also used intended for recording the actual position. A Voreinsteügläed is assigned to the position detector. A memory with scanning elements is also assigned to each detector. Each drive has a manual control member an automatic control element is assigned to all drives. Through the hand control leather, row and switching elements connected in parallel can be controlled, the control being controlled by actuating the automatic control element are controllable in another way. This results in a higher degree of circuit behavior Effort, which ■ results in susceptibility to failure.

It is therefore the object of the invention to design a circuit arrangement of the type mentioned at the outset in such a way that that in a simple manner one of the respective setting of the movement device actually corresponds Code combination recorded in the memory and can be made available again if necessary.

According to the invention, the object is achieved by the characterizing features of claim 1.

The invention is further developed by the features of the subclaims.

Due to the circuit arrangement according to the invention, the circuit complexity for the definition of many different setting positions of the movement device is particularly low. Here 1st advantageous that several different movement devices can be used, such as a pneumatic-hydraulic movement device, which, when centrally arranged, has an almost allows any number of movements in different coordinate directions. This is especially important if the equipment is a dental treatment chair. In this case The invention can be used in a more simple manner in multi-user systems in clinics or large practices will. Furthermore, in the case of pneumatic-hydraulic systems with spatially much smaller ones Drive systems can get along, in order to drive the respective movement device, that can respective work device, in particular the respective dental treatment chair, even narrow and run small. The work device can use all specified movement coordinates automatically by pressing keys one after the other into the corresponding desired Setting position.

The different, each characteristic CodeWofhblnatlonen can in different memory areas of the memory be arranged over are addressable to an encoder. Furthermore, a register can be provided between the encoder and the memory be, through which the corresponding target information, even if one of the keys is pressed briefly is obtained. By clock control, the safe takeover of each output from the encoder can be Address can be guaranteed. Are separate setting buttons for the respective setting of the movement device provided, the movement device can be set independently of the respective target information will. In addition, certain readjustment positions that are only required in each case can be stored in the memory the encoder can be stored and recalled, making any setting of the movement device can be done by actuating a special key associated with the encoder. In addition, reprogramming in can be achieved in a particularly simple manner with only a slight addition to the circuit arrangement.

Finally, the circuit arrangement according to the invention enables tracking can also be detected with the aid of the movement device Markings on the counter reading assigned to this in each case, if the counter has this counter reading has not reached due to interfering signals.

The invention is based on the embodiment shown in the single figure of the drawing Circuit arrangement explained in more detail.

The circuit arrangement shown is used to control the movement of an implement which is not shown in detail and which is in particular a dental treatment chair acts. With the help of the circuit arrangement, in the simplest case, the working device to be moved is in a single moving coordinate moves; But it is also possible to use the circuit arrangement for the control of movements in different movement coordinates. For this purpose there is only one the Movement device effecting movement of the implement in question for the respective movement coordinate to use.

The movement device, which is preferably a pneumatic-hydraulic movement device, is connected to a coding element 23, which can be formed by a perforated strip. This coding element 23 is connected to the movement device (not shown) in such a way that it moves with it. The perforated strip forming the coding element 23 has in the present case in two mutually different rows 24, 25 holes, through which markings are determined which correspond to certain positions of the direction of travel. The holes 29, 30, 34 present in one row 24 of the perforated strip 23 are used to derive clock pulses which are fed to a counter 4, which is still to be considered, at a clock input CLK. For this purpose, the relevant clock input CLK of the counter 4 is connected to a scanning device 32 which scans the holes in the row 24.

The second row of holes 25 of the perforated strip 23 has only three holes 16, 27 and 28 in the present case. These holes 26, 27 and 28 are characteristic of very specific setting positions of the movement device. Thus, the hole 26 of the lowest adjustment position, the hole 28 of the uppermost adjustment position and the hole 27 can correspond to the middle adjustment position of the movement device in question.

chen. These holes 26, 27 and 28 are scanned by means of a scanning device 31, which is as in of the scanning device 32 can be an optical scanning device. This means that the scanning devices 31, 32 can be formed by photocells, which each time a hole is detected Perforated tape 23 emit a corresponding output signal, which is, for example, a binary signal "H" acts.

With regard to the punched tape shown in the drawing: 23 it should also be noted that the holes 29 or 30 are provided at locations within the area lie, which is limited by the holes 26 and 28 of the other row 25. This is a differentiating wedge the holes 26 and 28 of the hole 27 is easily possible, as will be explained in more detail below becomes apparent.

The counter mentioned, which is an up / down counter 4, is connected to the output of the scanner 31 with a set-command line S. An input χ of a NAND element 12 is also connected to the output of this sampler 31. An unspecified advance position of the up / down counter 4 is connected to the output of a multiplexer II. This multiplexer 11 has two control inputs DO and Dl . The multiplexer 11 is connected to the output of the scanner 32 with the control input DO. With its control input Di , the multiplexer 11 is connected to the output of the NAND element 12. Depending on which control signals (binary signals) occur at the two control inputs DO and Dl of the multiplexer 11, this outputs one of several different code combinations to the pre-warming down counter 4 on the output side. This code combination tiQ ^ n L-jc »« A »£ · ... Vo ^ insiCuüu" of the Vo ™ 5rts reverse counter 11 can be used.

The up / down counter 4 is connected on the output side to the input of a memory 5 with random access (RAM) and to one input of a comparator 6. This comparator 6 is connected to the output of the memory 5. It compares the respective counter position Z with the respective output signal A of the memory 5.

An addressing input ADR of the memory 5 is connected to the output of a register 13 which is connected downstream of an encoder 14. This encoder 14 is connected on the input side to a series of keys 17, 18, 19 and 20. When one of these keys i7, 18, 19, 20 is actuated, it outputs an address for controlling a memory location or memory area of the memory 5. This address is held in register 13, to which a corresponding takeover clock pulse is fed to a clock input CLK from the output of a NAND element 15. The NAND element 15 is connected to all inputs of the encoder 14 to which the keys 17 to 20 are connected, and on the output side it is connected to the clock input CLK of the register 13 via a capacitor M. The (comparator 6 is connected with an output (Z> A) to an input of an OR element 7. The comparator 6 is connected to an input of an OR element 9 with a further output (Z <A). Member 7 is connected on the output side to an actuator 8, which can be a magnetic relay and is used to control the movement device in a certain direction, for example to perform a downward movement. Control gear VIR of the up / down counter 4. Depending on which binary signal (“H” or “L”) occurs at this control input VIR , the up / down counter 4 carries out either an upward counting or a downward counting Link 9 is connected on the output side to a corresponding actuating element 10, which can also be a magnetic relay, which, however, is used to control the movement device In ei Another direction of movement is used, for example to control an upward movement. This OR element 9 is also connected on the output side to an input of the NAND element 12 already mentioned above.

The OR gate 7 is connected to a further input with a setting button i, the actuation of which leads to the excitation of the magnetic relay 8 and thus to the downward movement of the movement device. That OR gate 9 is connected to a further input with a setting button 2, the actuation of which leads to that the magnetic relay 10 is energized and that an upward movement of the movement device takes place.

A NAND element 3 is connected on the input side to the two setting buttons 1 and 2. This NAND-GHed 3 is at its output on the one hand with a release input EN of the comparator 6 and on the other hand ml! connected to the input of an inverter 16. This inverter 16 is connected on the output side via a normally closed key 21 to that input of the encoder 14 to which the key 20 is connected. At the connection point of the output of the inverter 16 and the key 21, a further inverter 22 is also connected on the output side, to which control signals are supplied from a terminal 33 on the input side, which will be discussed in more detail below.

On the output side, the NAND element 3 is connected to a Schrelb control input WR of the memory 5 via a differential capacitor or differentiating element.

The connecting lines between the individual circuit devices, each marked by a short horizontal line the circuit arrangement shown can be formed by several individual lines be.

The mode of operation of the circuit arrangement shown is explained in more detail below. For this it is assumed that the circuit arrangement for controlling the movement of a dental treatment chair Serves in a movement coordinate. It is assumed that the two magnetic relays 8, 10, in which it can be, for example, solenoid valves, are de-energized. This means that the moving device is stopped. Now one of the keys 17 to 20 connected to the encoder 14 is actuated. With regard to these keys, it should also be noted that the key 17, for example, is in the position "Ausstelgen" from corresponds to the dental treatment chair that the button 18 corresponds to the position "spit out" that the key 19 corresponds to a desired setting position I and that the key 20 is a memory key IsL Has the dental treatment chair been in a working position, for example through the Setting position I is given and button 17 operated, so is z. B. an upward movement of the

IZ / DD

dental treatment chair and thus the movement equipment required. When the key 17 is actuated, the encoder 14 outputs a corresponding address which is held in the register 13. This address is used to control the memory 5 at its addressing input ADR . The memory 5 then outputs a code code A belonging to this address. Since this code combination A is different from the number Z output by the up-down counter 4, the comparator 6 outputs an output signal (binary signal "H"). In the present case, this output signal is emitted from the output of the comparator 6 connected to one input of the OR gate 9. The output of this output signal has the consequence that the magnetic relay 10 is excited and that the movement device is then controlled accordingly to perform an upward movement.

This excitation state of the magnetic relay 10 is maintained as long as the comparator 6 emits an output signal (binary signal “H”) from its output labeled Z <A. However, if the comparator 6 establishes an equality between the counter position Z of the up / down counter 4, which is changed by the clock pulses derived from the punches 34 of the moving hole drift 23, and the code combination A emitted by the memory 5, it indicates an equality in its counter position Z = A designates the output of a corresponding binary signal "H", while binary signals "L" occur at its other outputs. Then the magnetic relay 10 is de-energized again. The dental treatment chair is now shut down again.

Used in the course of the movement of the movement device with the aid of the scanner 31, 32 scanned a point of the perforated strip 23 at which one of the holes 26, 27 or 2 », the following processes take place. If one assigns the determination of one of the In the punched tape 23 contained holes through one of the two scanning devices 31, 32 a binary signal "H" to and If such a hole does not appear, a binary signal "L" exists between these binary signals and the output of the output of the OR gate 9 binary signals with regard to the output of Code combinations at the output of the multiplexer 11 «have the following relationships:

DO Ol

Setting the Multiplexer 11

H H L. L. FF H L. L. H 00 H L. H H XX H H H L. XX

From the top line of the table you can see that when determining the hole 28 Cx = "H") and when after Movement of the movement device carried out above (y = "H") at both inputs DO and Dl of the multiplexer 11 each has a binary signal "Lx", which means that the code combination FF from the multiplexer 11 is issued on the output side.

From the second line of the table one sees that the hole 26 is determined (x = "H") and that none Upward movement of the movement device is present. In this case, the OR gate 9 outputs a binary signal "L" which is output at the input ν of the NAND element 12 is now on Input Dl of the multiplexer 11 a binary signal "H", while the input DO of the multiplexer II again a binary signal "L" is supplied. Due to the appearance of these input signals there the multiplexer 11 on the output side the code combination 00 from.

From the third cell of the table it can be seen that the hole 27 of the perforated tape 23 has been determined, specifically when a downward movement is carried out by the movement device. In this case, the OR element 9 again emits a binary signal "L" (y = "L"), which in conjunction with the binary signal "H" at the input χ of the NAND element 12 leads to the input Dl of the multiplexer 11 a binary signal "H" occurs. In connection with the binary signal “H” occurring at the input DO of the multiplexer 11, this multiplexer 11 emits the code combination xx designated at one of its inputs with xx on the output side.

The last cell in the table shows that the hole 27 of the perforated strip 23 is determined when a movement is carried out in the other direction of movement. In this case, namely, the OR element 9 outputs a binary signal "H" (v = "H"), which in conjunction with the binary signal "H" occurring at the input χ of the NAND element 12 leads to the input Dl of the multiplexer 11 is now fed with a binary signal "L". In connection with the binary signal "H" occurring at the input DO of the multiplexer II, this leads to the multiplexer 11 emitting the code combination xx provided by a further input, also designated xx, at the output. This code combination is the same code combination as is provided by the other input of the multiplexer 11, labeled xx. This code combination is characteristic of the middle setting position of the movement device, while the other, above-mentioned code combinations FF, 00 of the multiplexer 11 are characteristic of the upper and lower position of the movement device.

The code combinations explained above, which are output from the multiplexer 11 on the output side in response to the explained input controls, are fed to the forward-backward counter 4 at the presetting input. In addition, a binary signal "H" is fed to the set input S of the counter 4 from the output of the scanning device 31 at the respective point in time; the corresponding counter position. This means that the code combination output by the multiplexer 11 in each case leads to the correction of the counter position of the up / down counter 4. As a result, incorrect settings of the up / down counter 4 can be corrected in the course of the movement of the movement device and thus of the perforated strip 23.

The solenoid relays 8, 10 or the solenoid valves can now not only from the output side of the ! Comparators- 6 can be controlled, but also by pressing the setting buttons 1, 2. By pressing the setting button 1 is given a binary signal "H" from the output of the OR gate 7, on its Occurrence towards the magnetic relay 8 is excited. When the setting button 2 is actuated, the magnetic relay 10 is energized. Pressing each of these two setting buttons 1, 2

also leads to the fact that the enable input EN of the! comparator-6 is supplied with a blocking signal (binary signal "H"). This binary signal “H” also reaches the input of the inverter 16 and is fed as a binary signal “L” via the closed switch 21 to the input s of the encoder 14 to which the key 20 is connected. This has the same effect as if key 20 were pressed. However, if the relevant setting button 1 or 2 is released again, a binary signal “L” occurs at the output of the NAND element 3, which is inverted by the inverter 16 as a binary signal “H” and fed to the aforementioned input of the encoder 14.

The encoder 14 thus sends the address corresponding to the key 20 to the register 13, with which a corresponding memory area in the memory 5 is addressed. Because at this point in time the Schrelb control gear WR of the memory S is also briefly fed a binary signal "H" via the capacitive connection to the output of the NAND element 3, the counter position Z of the up / down counter at the point in question becomes 4 Written into the addressed memory area of memory 5. The comparator 6 released again by its release input EN in this case emits a binary signal “H” at its output labeled Z = A and a binary signal “L” each at its other outputs. By actuating the two setting buttons 1, 2, a setting position of the movement device can thus be established, which can be set again at any time by subsequently actuating button 20.

The circuit arrangement now not only allows programming of the setting positions (readjustment position) of the movement device which can be called up or set by actuating the button 20, as has been explained above. Rather, the circuit arrangement in question also allows the setting! To program positions that can be called up by pressing buttons 17, 18, 19. For this purpose, the button 21 must first be opened. Then that key of the keys 17, 18, 19 is pressed, the setting position of which is to be vetted or reprogrammed. Then the movement device is brought into the desired setting position with the aid of the setting buttons 1, 2. The switch 21 is then closed again. By executing these actuation processes, the following processes take place in the circuit arrangement: Opening the key 21 ensures that the actuation of the setting keys 1, 2 does not result in the encoder 14 sending the address corresponding to the key 20 to the register 13. Rather, the address corresponding to the actuated key 17, 18 or 19 is transferred from the encoder 14 to the register 13. This address thus controls a correspondingly designated memory area of the memory 5. The counter position of the up / down counter 4, which has been changed accordingly by actuating the setting keys 1, 2, is written into this memory area at the moment at which the setting key 1 or 2 is released. At this moment, a write pulse (binary signal “H”) occurs briefly at the write input WR of the memory 5, as has already been explained above. The relevant adjustment position of the movement device can then then be called up again by pressing the respective key 17, 18 or 19.

Finally, it should also be noted that a corresponding plurality of memories are used for executing movements in different directions of movement according to your memory S can be provided. These memories can then all with their addressing inputs be connected together to the output of the register 13 and can by actuation can be addressed by the keys 17 to 20 corresponding to keys. Any such memory can then be assigned a separate sub-circuit arrangement, which has its own up-down counter with a multiplexer provided at the input and a comparator with evaluation elements connected downstream of this includes. This means that the circuit elements 13, 14, 15 and the buttons 17 to 21 together or can be provided centrally.

For this 1 sheet of drawing

Claims (7)

Patent claims: 1. Circuit arrangement for controlling the movement of a working device, in particular a dental treatment chair, between definable setting positions by delivering code combinations individually defining the individual setting positions from a memory (5) to a comparator <6), which is also provided by an up / down counter (4) Position signals representing actual information are fed to at least one movement device and which, if the signals (Z, A) compared by it are different, causes an output signal to reduce the difference between these signals (ZA) to the movement device , with which a clock pulse for changing the counter position of the up / down counter ί4) is connected to the device (23,32) M emitting, characterized in that the memory (5) has a signal input directly at a counter output (Z) of the forward Down counter (4) and with an addressing device ngang (ADR) is connected to an addressing device (13 to 22), from which adrettes for storing counter positions of the up-down counter (4) as desired setting positions defining code combinations or for sending such code combinations to the comparator (6) are. 2. Circuit arrangement according to claim 1, characterized in that the up-down counter (4) with a Vorr-pstellungselngang connected to the output of a multiplexer (H), which according to its respective control different code combinations (FF, 00, xx) for counter presetting and its Control of the occurrence of separate control pulses, which are linked to the movement device moving coding element (23) is generated in addition to the clock pulses, and is dependent on the direction of movement of the movement device. 3. Circuit arrangement according to claim 1 or 2, characterized in that the addressing device (13 to 22) has an encoder (14), which, upon actuation of keys (17, 18, 19, 20), sends out addresses identifying different memory areas of the memory (5). 4. Circuit arrangement according to claim 3, characterized in that between the encoder (14) and the memory (5) a register (13) is provided. 5. Circuit arrangement according to claim 4, characterized in that from the actuation one of the keys (17, 18, 19, 20) effectively controlling the transfer of the address which then occurs from the encoder (14) in the register (13) Clock pulse can be derived. 6. Circuit arrangement according to one of claims ω before 1 to 5, characterized in that the respective setting of the movement device by Actuation of the separate setting buttons (1,2) can be changed. 7. Circuit arrangement according to one of claims <> 5 before 3 to 5 and claim 6, characterized in that the connected to the encoder (14) individual keys (17, 18, 19, 20) associated code combinations in the memory (S) can be changed by actuating the respective button (17, 18,19 or 20) after the appropriately newly set movement device and one of the previously actuated adjustment boxes (1,2) is released, whereupon the respective moment existing counter position of the up / down counter (4) can be retained as a new code combination in the memory (5). 8. Circuit arrangement according to one of claims 3 to S or 7, characterized in that on one of the encoder (14) on its activation at a separate input fixed certain memory location of the memory (5) the existing at the moment in question counter position of the forward Down counter (4) can be held and can be called up again for comparison purposes in the comparator <6) upon a corresponding actuation of a key (20) connected to the separate input of the encoder (14).