JP5661069B2 - Slave station terminal - Google Patents

Description

  The present invention relates to a slave station terminal that transmits a control / monitoring signal to and from a control side via a common data signal line. The common data signal line is a signal line in which a plurality of slave station terminals are connected in parallel, and a control-side master station is connected in parallel with the plurality of slave stations.

  Parts, products, etc. are stored in a storage shelf or the like and taken out from there when necessary. Therefore, managing the information on the number of remaining parts and the position of the stored parts is important for improving manufacturing efficiency and product management. As a method for managing parts, for example, Patent Document 1 predicts the time when parts material is out of stock, and outputs parts out-of-stock warnings to the display devices installed in the material shelves that store the parts materials. The management method is described. However, the management method based on prediction has a problem that accurate management is difficult.

  In order to perform accurate management, a part or product take-in instruction or a confirmation switch input after take-out for a take-in instruction has been performed. In this case, the host computer sends a parts pick-up instruction to the control device, and the control device displays it via a slave station terminal including a lamp and a display device mounted on the storage shelf to which the pick-up instruction is issued. ing. On the other hand, an operator or robot that has finished taking instructed parts, etc. operates a lever switch provided in the slave station terminal as a take-off completion input, and the operation signal passes through the control device to the host computer. It has come to reach. Thus, the system is configured to prevent erroneous work, and manage work progress, replenishment of parts to a storage shelf, and inventory confirmation of parts.

JP 2001-79717 A

  However, in recent years, there are many small parts and commodities, and the storage shelves themselves are also miniaturized, and there is a problem that conventional slave station terminals equipped with lever switches are too large to be installed.

  On the other hand, when miniaturizing the slave station terminal, if the components are densely packed and the structure is made precise, there is a risk that it will be more susceptible to the static electricity generated by the operator than the conventional slave station terminal. there were. However, in order to prevent the influence from static electricity, it is not preferable to manufacture and arrange a special device because installation space is required and costs are increased.

  Accordingly, an object of the present invention is to provide a slave station terminal that can be installed on a miniaturized storage shelf and is not easily affected by static electricity generated by an operator.

  The slave station terminal according to the present invention is connected to the common data signal line to which the master station is connected, sets the address of the own station, receives a transmission signal from the master station, and matches the data of the own station address At the timing, the control data value of the control signal superimposed on the transmission signal is extracted, the signal corresponding to the control data value is output to the light projecting unit, and the monitoring data corresponding to the input signal from the light receiving unit is monitored An input / output unit that superimposes the transmission signal as a signal is provided. And the said light projection part is installed in the one of the divisions separated by the light-shielding means toward the perceiving window which has translucency. In addition, the light receiving unit is installed on the other side of the section separated by the light shielding unit toward the sensitive window, and a response that blocks transmission of the projected signal emitted from the light projecting unit outside the sensitive window. When the intention display body is disposed in contact with the sensing window, it receives a light projection signal emitted from the light projecting unit and reflected by the response intention display body, the light shielding means has conductivity, and the response intention display The body's charged static electricity can be led to earth.

  In the present invention, the response intention display body is used for an input operation on the slave station terminal, and corresponds to, for example, an operator's finger.

  The light shielding means is in contact with the inner surface of the sensing window and guides the charged static electricity of the response intention indicator to ground, and the response intention indicator which is emitted from the light projecting unit without contacting the inner surface of the sensing window. It may have a portion that transmits the light projection signal reflected at, and in that case, it may be configured by standing up a convex plate material in plan view.

  The display light emission means for performing the instruction display which can be visually recognized may be installed in the section where the light projecting unit is installed.

  The slave station terminal of the present invention adopts an optical detection method using a light projecting unit and a light receiving unit, so that the size of the component can be reduced as compared with the one using a mechanical detection method such as a conventional switch lever. The size can be reduced and the size can be reduced. In addition, since the light receiving unit and the light projecting unit are arranged separated from the light shielding means, even if the arrangement interval between the light projecting unit and the light receiving unit is shortened, the light projection signal is displayed as a response intention from the light projecting unit to the light receiving unit. It is possible to prevent direct incidence without being reflected by the body, and to suppress the occurrence of malfunction. Furthermore, since the charged static electricity of the response intention display body is guided to the ground through the light shielding means, the influence of the static electricity when the response intention display body charged with static electricity contacts can be suppressed to a low level.

  Furthermore, in the case where the display light emitting means is adopted to perform the instruction display that can be visually recognized by the operator, the display light emitting means is installed in the section where the light projecting unit is installed, and is emitted from the display light emitting means. It is possible to prevent malfunction of the light receiving unit due to light.

1 is a system configuration diagram showing a schematic configuration of a control / monitor signal transmission system using a slave station terminal according to the present invention. It is a system configuration | structure figure of a master station. It is a system block diagram of a slave station terminal. The light shielding means is schematically shown, wherein (a) is a plan view, (b) is a front view, and (c) is a side view. It is a schematic diagram of the transmission system between a master station and a slave station. It is a time chart figure of a transmission clock signal.

With reference to FIGS. 1 to 6, an example of a slave station terminal according to the present invention will be described by way of example when used in a control / monitor signal transmission system.
As shown in FIG. 1, the control / monitor signal transmission system includes a single master station 2 connected to a control unit 1 and common data signal lines DP and DN (hereinafter also referred to as transmission lines), It is composed of a plurality of slave stations 4 connected to the common data signal lines DP and DN and fixed to the pipe rack 10 of the storage shelf. The common data signal line DN is connected to the ground.

  The control unit 1 is, for example, a programmable controller, a computer, and the like, and receives the output unit 11 that transmits the control parallel data 13 and the monitoring parallel data 15 obtained based on the monitoring data extracted from the monitoring signal from the slave station 4. It has an input unit 12. These output unit 11 and input unit 12 are connected to the master station 2.

  As shown in FIG. 2, the master station 2 includes an output data unit 21, a timing generation unit 23, a master station output unit 24, a master station input unit 25, and an input data unit 26. A control signal (hereinafter referred to as a transmission clock signal) that is connected to the common data signal lines DP and DN and is a series of pulse signals corresponding to the transmission signal of the present invention is connected to the common data signal lines DP and DN. The monitoring parallel data 15 extracted from the monitoring signal sent from the slave station 4 is sent to the input unit 12 of the control unit 1.

  The output data unit 21 delivers the control parallel data 13 from the output unit 11 of the control unit 1 to the master station output unit 24 as serial data.

  The timing generation unit 23 includes an oscillation circuit (OSC) 31 and a timing generation unit 32. Based on the OSC 31, the timing generation unit 32 generates a timing clock of this system and supplies it to the master station output unit 24 and the master station input unit 25. hand over.

  The master station output unit 24 includes control data generating means 33 and a line driver 34. Based on the data received from the output data section 21 and the timing clock received from the timing generation section 23, the control data generation means 33 transmits a series of pulse signals to the common data signal lines DP and DN via the line driver 34. Send a clock signal.

  As shown in FIG. 5, the transmission clock signal has a control / monitoring data area following the start signal ST. The control / monitoring data area is composed of control signal data OUTn (n is an integer) sent from the master station 2 and monitoring signal data INn (n is an integer) sent from the slave station 4. As shown in FIG. 6, the pulse of the transmission clock signal has a high potential level (+ 24V in this embodiment) in the second half of one cycle and a low potential level (+ 12V in this embodiment) in the first half. The pulse width interval of the first half of the pulse that becomes the level becomes the output data period, and the first half of the pulse that becomes the low potential level also becomes the input data period. The pulse width interval of the low potential level represents the control signal data OUTn, and the presence or absence of the current superimposed on the low potential level represents the monitoring signal data INn. In this embodiment, when one cycle of the transmission clock signal is t0, the pulse width interval of the low potential level is extended from (1/4) t0 to (3/4) t0. As long as it corresponds to the value of each data of the control parallel data 13, the width is not limited and may be determined appropriately. Also, the input data period and the output data period can be appropriately determined. For example, the input data period is set to the first half of the pulse (low potential level) as in this embodiment, and the pulse width interval of the second half of the pulse (high potential level) is set. Alternatively, the output data period may be the first half of the pulse (low potential level) and the second half of the pulse (high potential level) may be the input data period as in this embodiment. Further, the latter half of the pulse (high potential level) may serve as both the output data period and the input data period. The same applies to the case where the second half of one cycle of the transmission clock signal is at a low potential level. In FIG. 5, the upper part shows the control data (output data) period, and the lower part shows the monitoring data (input data) period.

  The start signal ST has the same potential level as the high potential level of the transmission clock signal and is a signal longer than one cycle of the transmission clock signal.

  The master station input unit 25 includes a monitoring signal detection unit 35 and a monitoring data extraction unit 36. The monitoring signal detection means 35 detects the monitoring signal transmitted from the slave station 4 via the common data signal lines DP and DN. As described above, the data value of the monitoring signal is represented by the presence or absence of the current superimposed on the low potential level. After the start signal ST is transmitted, the monitoring signal is sequentially received from each of the slave stations 4. It has become. The monitoring signal data is extracted by the monitoring data extraction means 36 in synchronization with the signal of the timing generation means 32. Then, the monitoring signal data is sent to the input data unit 26 as serial input data.

  The input data unit 26 converts the serial input data received from the master station input unit 25 into parallel (parallel) data, and sends the parallel data to the input unit 12 of the control unit 1.

  The slave station 4 corresponds to the slave station terminal of the present invention, and includes an MCU that is a microcomputer control unit as an internal circuit inside a casing provided with a light-sensitive sensing window 42. . This MCU functions as the input / output unit 40 of the present invention. In addition, display means 8 and a sensor 9 are also arranged inside the housing of the slave station 4.

  As shown in FIG. 3, the input / output unit 40 includes a transmission receiving means 41, an address extracting means 43, an address setting means 44, a monitoring data sending means 46, a control data extracting means 81, an output means 82, and an input means 72. ing. Calculations and storages necessary for the processing of the input / output unit 40 are executed using the CPU, RAM, and ROM provided in the MCU. However, the relationship between the CPU, the RAM, and the ROM in each process of each means constituting the input / output unit 40 is omitted for convenience of explanation.

  The transmission receiving means 41 receives the transmission clock signal transmitted to the common data signal lines DP and DN, and delivers it to the address extracting means 43. The address extraction means 43 counts pulses starting from the start signal ST indicating the start of the transmission clock signal, and the monitoring data transmission means 46 at a timing when the count value coincides with the local address data set by the address setting means 44. And the control signal is delivered to the control data extracting means 81. The interface of the address setting means 44 can be operated from the outside of the housing of the slave station 4 shown in FIG. 1 and can easily set an arbitrary address value.

  The monitoring data transmission means 46 is enabled by the input timing delivered from the address extraction means 43, and sets the base current of the transistor TR to “on” or “off” based on the serial data delivered from the input means 72. When the base current is “on”, the transistor TR is turned “on”, and a current signal as a monitoring signal is output to the common data signal lines DP and DN. In this embodiment, as shown in FIG. 6, when the data value of the monitoring data is “1”, it is expressed by flowing a current (for example, 30 mA) of a predetermined value Ith or more. Therefore, for example, the monitoring data at addresses 0 (# ad0), 1 (# ad1), 2 (# ad2), and 3 (# ad3) of the signal shown in FIG. It represents 0 ”,“ 1 ”,“ 0 ”.

  The control data extraction unit 81 extracts a data value from the control signal delivered from the address extraction unit 43 and delivers it to the output unit 82 as serial data. The output means 82 converts the serial data delivered from the control data extraction means 81 into parallel data, outputs it to the light emitter 8 (corresponding to the display light emitter of the present invention), and turns on or turns off the light emitter 8. . A known LED is used as the light emitter 8.

  The sensor 9 is connected to the input means 72 and the output means 82. The sensor 9 includes a light projecting unit 91 that is connected to the output means 82 and emits light according to control data, and a light receiving unit 92 that receives a light projection signal emitted from the light projecting unit 91.

  The light projecting unit 91 and the light receiving unit 92 are mounted on a substrate divided into two sections by a light shielding unit 93. The light projecting section 91 is installed in one of the sections separated by the light shielding means 93, and the light receiving section 92 is installed in the other section separated by the light shielding means 93, respectively, facing the sensing window 42. The light emitter 8 is also disposed in the same section where the light projecting unit 91 is disposed.

  The light shielding means 93 is an upright plate material that is convex in plan view. A conductive material (for example, conductive plastic) is adopted as the plate material, and the convex portion 94 is in contact with the inner surface of the sensing window 42. The light shielding means 93 is connected to the ground via the common data line DN.

Next, the operation of the slave station 4 in the control / monitor signal transmission system configured as described above will be described.
The control unit 1 designates a shelf in which articles that need to be picked up by the worker are stored, and outputs control parallel data 13 for instructing the picking up of the worker to the master station 2. Receiving this, the master station 2 outputs a transmission clock signal in which the data of the control signal corresponding to the transmission clock signal corresponds to the control parallel data 13.

  The slave station 4 extracts the data value of the control signal corresponding to the local station address, and displays (lights up or turns off) the light emitter 8 according to the data value. Then, when the worker who has received the article designated in accordance with the display touches the sensing window 42 with the finger 95, the finger 95 functions as a response intention display body of the present invention, and is emitted from the light projecting unit 91 with the finger 95. A signal as an operator's response intention display is input to the input means 72 from the light receiving unit 92 that has received the reflected light projection signal. There are two systems of sensors 9, and a signal is input to the input means 72 when the light receiving unit 92 of one of the sensors 9 receives light. In addition, since the light receiving unit 92 and the light projecting unit 91 are arranged to be separated from the light shielding unit 93, it is possible to prevent the light projection signal from directly entering the light receiving unit 92 from the light projecting unit 91 without being reflected by the finger 95. Therefore, the occurrence of malfunction is suppressed. Furthermore, since the static electricity charged by the operator is guided to the ground through the light shielding means 93, the influence of the static electricity can be suppressed to a low level. Furthermore, since the light emitter 8 is also installed in the same section as the section where the light projecting section 91 is installed, the malfunction of the light receiving section 92 due to the light emitted from the light emitter 8 is prevented. Yes.

  When the operator touches the sensing window 42 of the slave station 4 with the finger 95, a monitoring signal corresponding to the input signal to the input means 72 is sent from the slave station 4 to the common data signal lines DP and DN. And the control part 1 receives the information with the response from an operator with this monitoring signal.

DESCRIPTION OF SYMBOLS 1 Control part 2 Master station 4 Slave station 8 Light emitter 9 Sensor 10 Pipe rack 11 Output unit 12 Input unit 13 Control parallel data 15 Monitoring parallel data 21 Output data part 23 Timing generation part 24 Master station output part 25 Master station input part 26 Input data part 31 OSC (oscillation circuit)
32 timing generation means 33 control data generation means 34 line driver 35 monitoring signal detection means 36 monitoring data extraction means 40 input / output unit 41 transmission reception means 42 sensing window 43 address extraction means 44 address setting means 46 monitoring data transmission means 72 input means 81 Control data extraction means 82 Output means 91 Light projecting part 92 Light receiving part 93 Light shielding means 94 Convex part 95 Finger TR Transistor

Claims (4)

Connected to the common data signal line to which the master station is connected,
Set the address of the own station, receive the transmission signal from the parent station, and extract the control data value of the control signal superimposed on the transmission signal at the same timing as the data of the own station address, A signal according to the value is output to the light projecting unit, and an input / output unit that superimposes the monitoring data according to the input signal from the light receiving unit on the transmission signal as a monitoring signal,
The light projecting portion is installed on one of the sections separated by the light shielding means toward the light-sensitive sensing window,
The light receiving unit is installed on the other side of the section separated by the light shielding means toward the sensitive window, and the response intention display blocks the transmission of the projected signal emitted from the light projecting unit outside the sensitive window. When a body is placed in contact with the sensing window, it receives a light projection signal emitted from the light projecting unit and reflected by the response intention display body,
The slave station terminal characterized in that the light shielding means is conductive and guides the charged static electricity of the response intention display body to ground.   The light shielding means is in contact with the inner surface of the sensing window and guides the charged static electricity of the response intention indicator to ground, and the response intention indicator which is emitted from the light projecting unit without contacting the inner surface of the sensing window. The slave station terminal according to claim 1, further comprising a portion that transmits the projection signal reflected by the light.   3. The slave station terminal according to claim 1, wherein display light emitting means for displaying an instruction that can be visually recognized is installed in the section where the light projecting unit is installed. 4. The slave station terminal according to claim 2, wherein the light shielding means is configured by raising a plate material having a convex shape in plan view.