JP2004166394A - Process controller and control board equipped therewith - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a process controller superior in workability after installation that allows replacements of a wire of a terminal block and an I/O board to be surely and safely performed even after the process controller is installed on a control board. <P>SOLUTION: The process controller comprises a base plate 10, an elongated printed substrate 20 of which the both ends are supported on the base plate 10 and which is installed on the base plate, the terminal block 21 and a connector 22 that are arranged in series in the longitudinal direction of the printed substrate 20, a metal protective cover 31 that surrounds the circumference of the connector installation part of the printed substrate leaving a space between the terminal block 21 and the connector 22, and an insulating plate 32 which partitions the terminal block 21 and the connector 22 and of which the both ends are attachable to both ends of the protective cover. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a process controller housed in a control panel interposed between a computer such as a monitoring device and an actuator or a sensor, and used for exchanging data between them.
[0002]
[Prior art]
Conventionally, valve opening control and flow rate control using a differential pressure sensor are sometimes performed by a centralized monitoring device, and a control panel is used to exchange data between them in such control. That is, a control signal from a monitoring device by a computer is transmitted to various actuators via a program of a process controller housed in the control panel, and output signals from various sensors are similarly transmitted to the monitoring device via a program of the process controller. Is communicating.
[0003]
A control panel (electric component storage panel) that accommodates such a process controller (control device) is known (for example, see Patent Document 1).
[0004]
The possible internal structure of such a conventional process controller is described below. The process controller includes, for example, a rectangular base plate, an elongated printed circuit board (terminal board) arranged side by side on the plate surface of the base plate while maintaining a predetermined gap, and a metal cover covering half of the base plate and the printed circuit board. It has. Note that, on each printed circuit board, an electric wire terminal block for connecting electric wires from an actuator or a sensor and an I / O board connector are arranged in series in the longitudinal direction of the board. The I / O board connector side of the printed circuit board is covered with a cover together with the I / O board, other CPU board and communication board connected thereto, and is protected from the outside. On the other hand, the terminal block is disposed on the printed circuit board in a state of being exposed to the outside of the cover in order to facilitate the wire connection operation.
[0005]
The cover includes a metal side cover attached along three adjacent edges of the base plate, and a metal partition provided upright between the terminal block of the printed circuit board and the I / O board connector. It consists of a cover and a metal upper cover that closes an upper opening formed by these covers.
[0006]
In addition, the printed circuit board has one end in the longitudinal direction fastened and fixed to an upright portion on the edge of the base plate by screws, and the other end engages with a resin fastener serving as a support, and secures these fastenings. Fixedly supported by the tool.
[0007]
[Patent Document 1]
JP-A-2002-43783 (pages 4 to 5, FIGS. 1 and 8)
[Problems to be solved by the invention]
The reason for covering the I / O board connector side of the elongated printed circuit board with the cover and exposing the terminal block side to the outside of the cover is that the I / O board connected to the I / O board connector is unexpectedly exposed as described above. This is to make it easier for the worker to perform the wiring work of the terminal block while protecting the terminal block from the impact. In particular, when referring to the wiring work for the terminal block related to the process controller, after the process controller is housed inside the control panel, the wiring of the control panel is often changed by opening the control panel door by changing the actuator connected to the control panel. The wiring workability can be considerably improved by exposing the terminal block to the outside of the cover.
[0008]
However, the cover of the conventional process controller is entirely made of a metal plate. In other words, since the partition cover is also made of a metal plate, the terminal block of the printed circuit board and the I / O board connector are separated by the metal plate. Therefore, for example, when the operator changes the wiring of the terminal block in a state where the process controller is housed inside the control panel, it is necessary to perform such work in a state where it is difficult for the operator to directly view the terminal block. May cause contact. As a result, if a voltage is applied to the electric wire, there is a possibility that an actuator connected to the electric wire, an I / O board, a CPU board, and the like inside the cover may be damaged due to a short circuit.
[0009]
On the other hand, in addition to the problem associated with the work of changing the wiring of the terminal block, the following problem occurs when the I / O board is replaced.
[0010]
Specifically, after accommodating the process controller in the control panel, the I / O board may be pulled out or replaced in addition to the above-described wire replacement of the terminal block. Here, since the I / O board once fitted to the I / O board connector has a large number of male terminals and female terminals engaged with each other, a considerable removal force is required to pull out the connector. I need. On the other hand, the printed circuit board has both ends directly or indirectly supported by the base plate, but does not have a structure for suppressing the floating of the printed circuit board in a direction away from the base plate surface. For this reason, when the I / O board is forcibly pulled out from the I / O board connector, the printed board is bent in a bow shape, and in the worst case, stress concentration occurs at a joint portion between the base plate and the printed board, and the printed board itself is damaged. There is a risk that it will.
[0011]
SUMMARY OF THE INVENTION It is an object of the present invention to provide a process controller having excellent workability after installation, in which wiring work of terminal blocks and replacement of I / O boards can be performed safely and reliably even after the process controller is mounted on a control panel. Is to provide.
[0012]
[Means for Solving the Problems]
In order to solve the above-described problem, a process controller according to the present invention includes a base plate, an elongated printed board supported on both ends by the base plate, and installed on the base plate, and arranged in series in a longitudinal direction of the printed board. A metal protective cover surrounding the connector mounting portion of the printed circuit board while leaving a space between the terminal block and the connector, a partition between the terminal block and the connector, and both ends of the protective cover at both ends. Insulating plates attachable to both ends.
[0013]
The terminal block provided on the printed circuit board and the connector are separated by an insulating plate constituting a part of the cover. The protective cover surrounds the periphery of the connector on the printed circuit board. Therefore, the I / O board or the like connected to the connector of the printed circuit board is reliably protected by the protective cover and the insulating plate. In addition, when the wiring of the terminal block is changed, the wiring does not contact with the metal partition plate and short-circuit (short) due to the existence of the insulating plate due to the presence of the insulating plate.
[0014]
According to a second aspect of the present invention, there is provided a process controller according to the first aspect, wherein one edge portion of the insulating plate is attached to the protective cover in a state of being in contact with the printed circuit board.
[0015]
The insulating plate constantly presses the printed board, which is supported at both ends and supported by the base plate in a bridge structure, against the base plate. Therefore, when the I / O board or the like is pulled out from the connector, the printed circuit board is prevented from bending in the board pulling-out direction. As a result, stress is not concentrated on the board support portion due to the bending of the board, and the board can be prevented from being damaged.
[0016]
According to a third aspect of the present invention, in the process controller according to the first aspect, the printed board includes a plurality of printed boards arranged in parallel with a base plate, and the insulating board includes a single insulating board. It is attached to the protective cover in a state of contacting each of the substrates.
[0017]
By pressing a plurality of printed circuit boards with a single insulating plate, the floating of each printed circuit board with respect to the base plate is prevented. Therefore, it is not necessary to perform screwing or mounting of a special angle on the printed circuit board to prevent the board from being lifted, and the assembling workability is excellent.
[0018]
A control panel according to a fourth aspect of the present invention is a control panel including the process controller according to any one of the first to third aspects. Such a control panel is easy to perform wiring replacement work and board replacement work of the process controller housed in the control panel, and is excellent in maintainability and reliability.
[0019]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, a process controller according to an embodiment of the present invention will be described with reference to the drawings.
[0020]
As shown in FIG. 1, a process controller 1 according to an embodiment of the present invention is used for controlling the opening of a valve 101, controlling the flow rate by a differential pressure sensor 102, and the like, and intervening between a monitoring device 100 and these actuators and sensors. Are control devices housed in the control panels 111, 112,. Then, as shown in FIG. 2, a rectangular base plate 10, an elongated printed circuit board 20 arranged side by side while maintaining a predetermined gap between the plate surface of the base plate 10, and approximately half of the base plate 10 and the printed circuit board 20 And a cover 30 (see FIG. 4). In FIG. 2, for convenience of explanation, only two printed circuit boards 20 are shown.
[0021]
On each printed circuit board 20, a wire terminal block 21 connected to the actuator and an I / O board connector 22 connected to an I / O board (not shown in FIG. 2) are arranged in series in the longitudinal direction of the board. I have. The terminal block 21 and the I / O board connector 22 are electrically connected by a wiring pattern (not shown) on a printed circuit board. FIG. 2 does not show the terminal print display section on the printed circuit board 20.
[0022]
Then, the I / O board connector side of the printed circuit board 20 is covered with the I / O board and other CPU board 25 and the like, together with the I / O board connector 25 and the cover 30 except for the space between the terminal block 21 and the I / O board connector 22. (See FIG. 4) and are protected from the outside. On the other hand, the terminal block 21 is exposed to the outside of the cover in order to facilitate the wire connection operation.
[0023]
The printed circuit board 20 is attached to the base plate 10 so as to maintain the above-described state. More specifically, as shown in FIG. 5, the printed circuit board 20 has a protrusion 20a at one end in the longitudinal direction which engages with a long hole 11a formed in the upright portion 11 on the edge of the base plate, and the other end serves as a support. It is supported on the base plate in a crosslinked manner by engaging with a resin fastener 12 having The fastener 12 includes a base 12 a fixed on the base plate 10, a positioning protrusion 12 b that engages with an engagement hole (not shown) of the printed circuit board 20, and a claw that latches and engages with an edge of the printed circuit board 20. A portion 12c.
[0024]
That is, a support 13 made of resin is attached to the base plate 10 corresponding to each printed circuit board 20. The support 13 has a flat portion 13a at the head, and the bottom surface of each printed circuit board 20 comes into contact with this flat portion. A washer 13w for fine height adjustment is interposed between the support 13 and the base plate 10. Then, the printed circuit board 20 secures insulation from the metal base plate 10 by the crosslinked structure.
[0025]
The printed circuit board 20 has both ends supported by the base plate 10 in a bridge structure, and pulls the I / O board connector 22 of the printed circuit board 20 to the side opposite to the base plate 10 when a partition cover 32 described later is not attached. Then, the printed circuit board 20 bends (floats) in a bow shape on the opposite side to the base plate 10. Note that the printed circuit board 20 is not provided with a fastener to the base plate 10 for preventing such floating. This is in order to avoid a situation in which when a plurality of printed boards 20 are fastened to the base plate 10 for each board using screws or the like, the assembling work efficiency is extremely reduced. In addition, this is also to prevent one of the screws from dropping due to the vibration of the control panels 111, 112, etc., thereby causing a short circuit of the electric circuit.
[0026]
On the other hand, in order to eliminate the floating of each printed circuit board 20 without using a fastener on the printed circuit board 20 as described above, a structure in which a plurality of printed circuit boards 20 are collectively restrained via a resin bracket may be considered. The addition of a dedicated bracket undesirably leads to an increase in the number of parts.
[0027]
Next, the structure of the cover 30 will be described.
[0028]
The cover 30 includes a metal side cover (protective cover) 31 attached along three adjacent edges of the base plate 10 as shown in FIGS. A partition cover (insulating plate) 32 (FIGS. 3 and 4) partitioned between the O-board connector 22 and a metal upper cover 33 for closing an upper opening formed by the covers 31 and 32. (FIG. 4). In FIG. 2, the side cover 31 is partially cut away.
[0029]
The partition cover 32 is made of, for example, an insulating member such as a glass epoxy resin such as a printed board, and both ends of the partition cover protrude from the metal side cover 31 (one connection portion 31a in FIG. 2). (Only shown) and a resin fastener 41 for detachable connection. The upper cover 33 has a protrusion (not shown) formed on one side edge thereof engaged with an engagement hole (not shown) of the partition cover, and the other side edge protrudes from the side cover 31. The formed engaging pieces 31c and 31d are engaged with each other via a fastener 42. The side cover 31, the partition cover 32, and the upper cover 33 are each provided with a plurality of elongated heat radiation holes 31e, 32e, 33e for radiating internal heat (only some of the holes are shown in the figure). The side cover 31 has a hole (not shown) for connecting a communication code with an external computer.
[0030]
Since the partition cover 32 is attached as described above, the partition between the terminal block 21 and the I / O board connector 22 provided on the plurality of printed circuit boards 20 is separated by the partition cover 32 made of an insulating plate. .
[0031]
On the other hand, the lower edge portion of the partition cover 32 is attached to the side cover 31 in a state in which the lower edge portion is in contact with each board surface of the plurality of printed boards 20. As a result, the partition cover 32 always presses the printed board 20 supported at both ends and attached to the base plate 10 in a bridge structure to the base plate side, so that any printed board 20 is not bent in the direction away from the base plate 10. Has become.
[0032]
Next, an assembling method and operation of the process controller 1 will be described.
[0033]
First, a plurality of printed circuit boards 20 are attached to the base plate 10. In mounting the printed circuit board 20, in addition to the printed circuit board 20 on which the terminal block 21 and the I / O board connector 22 are mounted, a printed circuit board on which a CPU board connector and a communication connector not described in detail here are mounted. Also attach 50. At the time of mounting the printed circuit board 20 on which the terminal block 21 and the I / O board connector 22 are mounted, one end of the printed circuit board 20 is engaged with the elongated hole 11a of the base plate edge rising portion 11 as is apparent from the above-described configuration. Let it. Then, the positioning hole at the other end of the board is engaged with the positioning projection 12b of the fastener 12, and the edge of the printed circuit board 20 is latched with the latch claw 12c of the fastener 12. The above-described support 13 is attached to the base plate 10 in advance, and the printed circuit board 20 is supported at a substantially central portion other than both ends.
[0034]
Next, the side cover 31 and the insulating partition cover 32 are attached. Also, an I / O board (not shown) is inserted into the I / O board connector 22 of the printed circuit board. At the same time, a CPU board (not shown) is inserted into the CPU board connector 50, and the communication board 51 is inserted into the communication board connector.
[0035]
Then, the upper cover 33 is attached, and the assembly of the process controller 1 is completed.
[0036]
By attaching the partition cover 32 in this manner, the printed circuit board 20 is prevented from floating from the base plate 10. As a result, there is no need to attach each printed circuit board 20 to the base plate 10 with fasteners such as screws, and the assembling workability is significantly improved. Further, it is not necessary to attach another member such as an L-shaped angle to each printed circuit board 20 in order to prevent the printed circuit board 20 from bending.
[0037]
Subsequently, the process controller 1 thus assembled is mounted in the control panels 111, 112,..., And wiring work to the terminal block 21 and communication with an external computer are performed with the doors of the control panels 111, 112,. Perform the connection work for the cord.
[0038]
Since the wiring connection work in a state where the process controller 1 is housed in the control panels 111, 112,... Is difficult to see, the worker, during the wiring work, places the conductor exposed portion of the electric wire on the partition cover near the terminal block as described above. 32 may accidentally come into contact. However, since the partition cover 32 is made of an insulating material, the electric wire does not short-circuit (short-circuit) even when such a situation occurs while a voltage is applied to the electric wire. Therefore, the worker can perform such a difficult wiring connection work with ease. In addition, even if the wiring of the process controller 1 is changed due to the addition or change of the actuator or the sensor, the worker can similarly change the wiring of the electric wire with ease.
[0039]
On the other hand, I / O boards and CPU boards may be replaced depending on the usage of the control panels 111, 112,. In such a case, when the upper cover 33 of the process controller 1 is removed and the I / O board is pulled out, the printed circuit board 20 is also pulled together and the board itself tends to rise, but all the printed circuit boards 20 are mounted on the terminal block 21. The printed circuit board 20 is not lifted with respect to the base plate 10 because the partition board 32 is pressed by the lower edge of the partition cover 32 between the I / O board connector 22 and the I / O board connector 22. Therefore, the support portions at both ends of the printed circuit board 20 are not damaged by stress concentration.
[0040]
FIG. 6 is a plan view showing a modification of the process controller according to the above-described embodiment of the present invention with the upper cover 33 removed. Here, the printed circuit board is composed of various kinds of printed circuit boards 20 ', 20 ",... In addition to the above-described printed circuit board 20, each having an appropriate number of terminal blocks and I / O board connectors. Are mounted on the base plate 10 in the same configuration as described above, and the terminal block and the I / O board connector on the printed circuit board are arranged in the longitudinal direction of the board. Therefore, the same effects as those of the above-described embodiment can be obtained by providing the partition cover 32 made of an insulating plate.
[0041]
【The invention's effect】
As described above, in the process controller according to the present invention, the terminal block provided on the printed circuit board and the connector are separated by the insulating plate constituting a part of the cover. The protective cover surrounds the periphery of the connector on the printed circuit board. Therefore, the I / O board and the like connected to the connector of the printed circuit board are surely protected by the protective cover and the insulating plate, and when the wiring of the terminal block is changed, the wiring contacts the metal partition plate as in the conventional case. And no short circuit occurs.
[0042]
Further, in the process controller according to the second aspect of the present invention, the insulating plate always presses the printed board, which is supported at both ends and supported by the base plate in a bridge structure, toward the base plate. Therefore, when the I / O board or the like is pulled out from the connector, the printed board is prevented from floating in the board pulling-out direction. As a result, it is possible to avoid the board from being damaged due to the concentration of stress on the board supporting portion due to the lifting of the board.
[0043]
Further, the process controller according to the third aspect of the present invention prevents the plurality of printed circuit boards from lifting against the base plate by holding the plurality of printed circuit boards with a single insulating plate. Therefore, it is not necessary to perform screwing or mounting of a special angle on the printed circuit board to prevent the board from being lifted, and the assembling workability is excellent.
[0044]
A control panel according to a fourth aspect of the present invention is a control panel including the process controller according to any one of the first to third aspects, and the wiring of the process controller housed in the control panel is changed. This control panel is easy to perform work and board replacement work, and has excellent maintainability and reliability.
[Brief description of the drawings]
FIG. 1 is a schematic diagram illustrating a use mode of a process controller according to an embodiment of the present invention.
FIG. 2 is a perspective view showing the process controller according to the embodiment of the present invention with a partition cover and an upper cover removed.
FIG. 3 is a perspective view showing the process controller according to the embodiment of the present invention with an upper cover removed.
FIG. 4 is a perspective view showing a process controller according to one embodiment of the present invention.
FIG. 5 is a perspective view showing a method of attaching a printed circuit board of the process controller shown in FIGS. 2 to 4 to a base plate.
FIG. 6 is a plan view showing a modification of the process controller of FIG. 2 with an upper cover removed.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Process controller 10 Base plate 11 Standing part 11a Slot 12 Fastener 12a Base 12b Positioning projection 12c Claw 13 Support 13a Flat part 20, 20 ', 20 "Printed circuit board 20a Projection 21 Terminal block 22 I / O board connector 25 CPU board 30 Cover 31 Side cover 31c, 31d Engagement piece 31e Heat dissipation hole 32 Partition cover 32e Heat dissipation hole 33 Upper cover 33e Heat dissipation hole 41 Fastener 50 Printed circuit board 100 Monitoring device 101 Valve 102 Differential pressure sensor 111, 112.

Claims (4)

A base plate,
An elongated printed board that is supported on both ends of the base plate and is laid on the base plate;
A terminal block and a connector arranged in series in the longitudinal direction of the printed circuit board,
A metal protective cover surrounding the periphery of the connector mounting portion of the printed circuit board while leaving between the terminal block and the connector,
A process controller comprising a partition between the terminal block and the connector, and an insulating plate having both ends attached to both ends of the protective cover. 2. The process controller according to claim 1, wherein the insulating plate is attached to the protective cover such that one edge of the insulating plate is in contact with the printed circuit board. 3. The printed circuit board is composed of a plurality of printed boards arranged in parallel with the base plate, and the insulating plate is formed of a single insulating plate and can be attached to the protective cover while being in contact with each of the printed boards. The process controller according to claim 1, wherein the process controller comprises: A control panel comprising the process controller according to claim 1.

Images