Abstract: A programming assist device for a PLC program and a programming assist method for a PLC program capable of easily preparing separate executable files for causing redundant CPUs of a PLC to operate and reliably preventing an emergency stop of the PLC due to a failure in converter software are provided. First and second intermediate codes are generated from an original program. An inverse conversion program is generated from the first intermediate code. A reconverted first intermediate code and a reconverted second intermediate code are generated from the inverse conversion program. In the case where the intermediate codes and the reconverted intermediate codes match each other, a first executable file is generated from the reconverted first intermediate code, and a second executable file is generated from the reconverted second intermediate code. The executable files are transferred to the PLC.

Abstract: A method of inspecting a RAM of a programmable logic controller is provided that enables all unit storage regions in a RAM inspection region to be inspected in about several minutes and that meets a predetermined safety standard. The inspection method includes the steps of: (a) dividing a RAM inspection region, which is a region of the RAM to be inspected, into a plurality of blocks; and (b) by a control device, writing a predetermined value into unit storage regions in a combination of blocks obtained by combining two blocks extracted from the divided blocks and thereafter sequentially inspecting whether or not values read from the unit storage regions each coincide with the written value. Step (b) is executed for all combinations of two blocks extracted from the divided blocks.

Abstract: A programming assist device for a PLC program and a programming assist method for a PLC program capable of easily preparing separate executable files for causing redundant CPUs of a PLC to operate and reliably preventing an emergency stop of the PLC due to a failure in converter software are provided. First and second intermediate codes are generated from an original program. An inverse conversion program is generated from the first intermediate code. A reconverted first intermediate code and a reconverted second intermediate code are generated from the inverse conversion program. In the case where the intermediate codes and the reconverted intermediate codes match each other, a first executable file is generated from the reconverted first intermediate code, and a second executable file is generated from the reconverted second intermediate code. The executable files are transferred to the PLC.

Abstract: A method of inspecting a RAM of a programmable logic controller is provided that enables all unit storage regions in a RAM inspection region to be inspected in about several minutes and that meets a predetermined safety standard. The inspection method includes the steps of: (a) dividing a RAM inspection region, which is a region of the RAM to be inspected, into a plurality of blocks; and (b) by a control device, writing a predetermined value into unit storage regions in a combination of blocks obtained by combining two blocks extracted from the divided blocks and thereafter sequentially inspecting whether or not values read from the unit storage regions each coincide with the written value. Step (b) is executed for all combinations of two blocks extracted from the divided blocks.

Abstract: A common library stores therein user function blocks and ready-made protected function blocks. By being manipulated by the user, an editing device links some of function programs stored in the function blocks in the library to form a control program which controls the exchange of signals between I/O modules and external devices. A control section in the terminal device allows the alteration of the function programs included in the user function blocks, but inhibits the alteration of the function programs included in the protected function blocks.

Abstract: The PLC according to this invention includes I/O modules, a CPU module, an input/output bus, and a PC having a display. The CPU module includes a control program storage unit which previously stores an intrinsic control program in which operation processing and an input/output information item are packaged; a library which previously stores the function block representing the operation processing; and a header file which previously stores equivalent input/output information equivalently representing the input/output information by a graphical language. Referring to the library and header file, PC causes the execution program created and stored in the main storage unit to be displayed on the display by the function block and equivalent input/output information item.

Abstract: A common library stores therein user function blocks and ready-made protected function blocks. By being manipulated by the user, an editing device links some of function programs stored in the function blocks in the library to form a control program which controls the exchange of signals between I/O modules and external devices. A control section in the terminal device allows the alteration of the function programs included in the user function blocks, but inhibits the alteration of the function programs included in the protected function blocks.

Abstract: Disclosed is a laser pulse controlling circuit that, when the laser device is driven with laser pulses having the first and the second illumination levels, causes the first and the second illumination level setting units to set the first and the second illumination levels corresponding to a predetermined ratio of the first illumination level to the second illumination level, wherein the laser pulse controlling circuit, based on regularity that the relation between: a manipulated variable for causing the second illumination level setting unit to execute adjustment of the second illumination level; and the inverse of the ratio, with reference to the first illumination level, is a straight line that necessarily passes one point for a predetermined first illumination level, and that the slope of the straight line is proportional to an arbitrary first illumination level, calculates the manipulated variable that is correlated with the first illumination level corresponding to the optical disk, and with the inverse

Abstract: The PLC according to this invention includes I/O modules, a CPU module, an input/output bus, and a PC having a display. The CPU module includes a control program storage unit which previously stores an intrinsic control program in which operation processing and an input/output information item are packaged; a library which previously stores the function block representing the operation processing; and a header file which previously stores equivalent input/output information equivalently representing the input/output information by a graphical language. Referring to the library and header file, PC causes the execution program created and stored in the main storage unit to be displayed on the display by the function block and equivalent input/output information item.

Abstract: Disclosed is a laser pulse controlling circuit that, when the laser device is driven with laser pulses having the first and the second illumination levels, causes the first and the second illumination level setting units to set the first and the second illumination levels corresponding to a predetermined ratio of the first illumination level to the second illumination level, wherein the laser pulse controlling circuit, based on regularity that the relation between: a manipulated variable for causing the second illumination level setting unit to execute adjustment of the second illumination level; and the inverse of the ratio, with reference to the first illumination level, is a straight line that necessarily passes one point for a predetermined first illumination level, and that the slope of the straight line is proportional to an arbitrary first illumination level, calculates the manipulated variable that is correlated with the first illumination level corresponding to the optical disk, and with the inverse

Abstract: In a transport mechanism of a sorting machine for large thin objects, objects to be transported (paper sheets such as postal matter) stored in transport boxes can be made collectable into smaller collection boxes than the transport boxes. The transport boxes storing and transporting the paper sheets given sorting information are attached to a free chain which is supported by the rail that is twisted and always drives, and when it approaches a spot where the rail is twisted, the free chain is also twisted following the rail. The transport boxes attached to the free chain are also tilted at the same time, and the paper sheets reach an end surfaces on the side at which the transport boxes are lowered and are positioned.

Abstract: In a transport mechanism of a sorting machine for large thin objects, objects to be transported (paper sheets such as postal matter) stored in transport boxes can be made collectable into smaller collection boxes than the transport boxes. The transport boxes storing and transporting the paper sheets given sorting information are attached to a free chain which is supported by the rail that is twisted and always drives, and when it approaches a spot where the rail is twisted, the free chain is also twisted following the rail. The transport boxes attached to the free chain are also tilted at the same time, and the paper sheets reach an end surfaces on the side at which the transport boxes are lowered and are positioned.

Abstract: An apparatus for picking up a plurality of papers stacked in an upright position one by one is disclosed. A pick-up mechanism is angularly movable about a single point between a position for sucking the outermost paper and a position for conveying it. While an sending mechanism sends air toward the bottom of a stack of papers positioned on a tray, the pick-up mechanism sucks the outermost paper and moves away from the other papers at a low speed. After the pick-up mechanism has conveyed the above paper, it moves toward she next paper for sucking it at a high speed. Air being sent from the above mechanism insures the separation of the consecutive papers. Because the pickup mechanism retaining the outermost sheet by suction moves slowly away from the other papers, the outermost paper is easily spaced from the other papers and therefore more surely separated from the other papers. This obviates a shearing force otherwise acting on and damaging, e.g., letters and magazines of delicate quality.

Abstract: An apparatus for picking up a plurality of papers stacked in an upright position one by one is disclosed. A pick-up mechanism is angularly movable about a single point between a position for sucking the outermost paper and a position for conveying it. While an sending mechanism sends air toward the bottom of a stack of papers positioned on a tray, the pick-up mechanism sucks the outermost paper and moves away from the other papers at a low speed. After the pickup mechanism has conveyed the above paper, it moves toward the next paper for sucking it at a high speed. Air being sent from the above mechanism insures the separation of the consecutive papers. Because the pick-up mechanism retaining the outermost sheet by suction moves slowly away from the other papers, the outermost paper is easily spaced from the other papers and therefore more surely separated from the other papers. This obviates a shearing force otherwise acting on and damaging, e.g., letters and magazines of delicate quality.