JPS5847726B2 - printed wiring board equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a printed wiring board in which a plurality of printed wiring board groups are commonly connected to a main common signal bus, and signals are exchanged between the main common signal bus and these printed wiring board groups. The present invention relates to a wiring board device, and enables maintenance of any group of printed wiring boards in an online state.

Generally, in electronic devices such as process control devices and electronic computers, a so-called nest structure is often adopted in which a plurality of printed wiring board groups are commonly connected to a common signal bus.

FIG. 1 is a main part configuration diagram showing an example of a process control device having such a nested structure, in which NCB is a main common signal bus, NEST1 to NESTn are printed wiring board groups, and printed wiring board groups NEST1 to NESTn are printed wiring board groups. NESTn are commonly connected to the main common signal bus NCB.

Note that the printed wiring board groups NEST1 to NESTn each include one control printed wiring board NCM1 to NCMn1.
Multiple controlled printed wiring boards AIO, AII, STI,
STO, etc., and sub-common signal buses NIB1 to NIBn, and control printed wiring boards NC M, to NC
Mn is connected to the common signal bus NCB and to each sub-common signal bus NIB1 to NIB, and the controlled printed wiring board S is connected to a predetermined sub-common signal bus NIB.
It is commonly connected to IB, -NIBn.

Note that an operating end, a detection end, etc. are connected to the controlled printed wiring board, but these are not shown.

In such a configuration, when performing maintenance on any printed wiring board group, it is necessary to drive the process control device without causing any disturbance to the signal exchange operation between other printed wiring board groups and the main common signal bus. It is desirable to be able to do this while online.

Conventionally, in order to achieve this purpose, for example, as described in Japanese Unexamined Patent Publication No. 51-9351, the length of the connector pins of the package is divided into multiple types to detect the transient state during insertion and removal. It has been proposed to lock the active signal on the bus line with this detection signal.

However, such a conventional configuration is undesirable because the operation of each package connected to the bus line is temporarily locked during the transition of insertion and removal of packages.

The present invention solves these drawbacks,
In a printed wiring board device in which a plurality of printed wiring board groups are connected to a main common signal bus and signals are exchanged between the main common signal bus and these printed wiring board groups,
Each of the printed wiring board groups is connected to a control printed wiring board connected to the main common signal bus through a connector that is attached and detached by a set screw, and a plurality of control printed wiring boards connected to the control printed wiring board via a sub-common signal bus. and a controlled printed wiring board, and on each of these control printed wiring boards, a switch means that generates a contact signal in conjunction with the attachment/detachment operation of the connector by the set screw, and a main common signal bus line according to the contact signal of this switch means. and a gate circuit for controlling electrical connection, and prior to removing the connector from the control printed wiring board, the gate circuit is closed to establish the electrical connection between the main common signal bus and the control printed wiring board. and after inserting the connector into the control printed wiring board, the gate circuit is used to make the electrical connection between the main common signal bus and the control printed wiring board conductive. This allows maintenance to be performed on any printed wiring board group in an online state without affecting the operation of the wiring board group at all.

Hereinafter, a detailed explanation will be given using the drawings.

FIG. 2 is a structural explanatory diagram showing an embodiment of the present invention,
A shows the removed state, and b shows the inserted state.

In Figure 2, NCM is a control printed wiring board, CON
is a connector for connecting the control printed wiring board NCM and the main common signal bus NCB.

A control printed wiring board NCM is provided with a microswitch 1 that is interlocked with the attachment/detachment operation of the connector CON, and a front plate 2 is attached to the end face of the microswitch 1, and an insertion end 3 is formed.

Further, a nut 4 is attached to the front plate 2 so as to face the operating end 1' of the microswitch 1.

On the other hand, the connector CON includes a cover 5, a contact end 6 that fits into the insertion end 3 of the control printed wiring board NCM, and a set screw that is screwed into the nut 4 and is used as a mounting member to drive the operating end 1' of the microswitch 1. It is composed of etc.

Note that the main common signal bus N is connected to the contact piece 6 of the connector CON.
CB is connected.

FIG. 3 is a circuit diagram showing an example of the electrical configuration of FIG. 2, and the same parts as in FIG. 3 are given the same reference numerals.

In FIG. 3, gate circuits 01 to Gm are opened and closed in response to contact signals from the microswitch 1, and control signal transmission from the control printed wiring board NCM to the main common signal bus NCB.

IN, .about.IN, are inverters that invert the input signal from the main common signal bus NCB and send it to a predetermined controlled printed wiring board (not shown).

In such a configuration, the operation is as follows.

Normally, the connector CON is inserted into the control printed wiring board NCM, and the set screw 7 is tightened into the nut 4, as shown in FIG. 2b.

In this state, the operating end 1' of the microswitch 1 is pressed by the set screw 7, and the contacts of the microswitch 1 are closed.

Therefore, the gate circuits G1 to Gm are opened and are in a state where signals can be sent from the control printed wiring board NCM to the main common signal bus NCB.

When performing maintenance in such a state, first remove the set screw 7 from the nut 4.

Here, by configuring the microswitch 1 so that the contacts of the microswitch 1 are reversed (connection → disconnection) before the set screw 7 comes off from the nut 4 of the front plate 2, the connector CON can be connected from the control printed wiring board NCM. Prior to removal, the gate circuits 01 to Gm can be closed to cut off the electrical connection between the main common signal bus NCB and the control print NCM.

In this manner, the connector CON is removed from the control printed wiring board NCM with the electrical connection between the main common signal bus NCB and the control printed wiring board NCM disconnected.

On the other hand, when the connector CON is inserted into the control printed wiring board NCM, the contacts of the microswitch 1 are disconnected, so the gate circuits G1 to Grr1 are closed.

After inserting the connector COM into the control printed wiring board NCM, the set screw 7 is tightened to reverse the contact point of the microswitch 1 (from disconnected to connected).

As a result, the gate circuits 01 to Gm are opened, and a signal can be sent from the control printed wiring board NCM to the main common signal bus line NCB.

Furthermore, if you forget to tighten the setscrew 7, the printed wiring board group including the pedestal printed wiring board will be considered to be under maintenance, so it is possible to prevent accidents caused by incomplete insertion. can.

During this series of maintenance, only the printed wiring board group to be maintained is connected to the main common signal bus N.
It is electrically isolated from the CB and does not affect the operation of other printed wiring board groups at all.

In addition, in this embodiment, an example is shown in which a microswitch operated by a set screw of a connector is used as a switch means linked to the attachment/detachment operation of a connector, but the present invention is not limited to this. A reed switch may also be used.

In this case, can you configure the switch to be magnetically driven with the set screw tightened? Ku.

Furthermore, although this embodiment shows an example in which the signal sent to the main common signal bus is controlled by the gate circuit, a gate circuit may also be provided for the input signal if necessary.

As explained above, according to the present invention, a printer with a relatively simple configuration can perform maintenance on any group of printed wiring boards in an online state without affecting the operation of other groups of printed wiring boards at all. A wiring board device can be realized, and it is suitable for electronic equipment having a nested structure.

[Brief explanation of the drawing]

Fig. 1 is a main part configuration diagram showing an example of a process control device having a nested structure, Fig. 2 is an explanatory diagram showing the structure of an embodiment of the present invention, and Fig. 3 is an example of the electrical configuration of Fig. 2. FIG. NCB... Main common signal bus, NEST, ~NE
STm...Printed wiring board group, NCM1 to NC
MRI・・・Control printed wiring board, AIO, AIT
, STI, STO... Controlled printed wiring board,
NIB1 to NIBn... Sub-common signal bus, 1.
...Micro switch, 2...Front plate,
3...Insertion end, 4...Nut, 5...
...Cover, 6...Contact piece, 7...
Set screw, 8...Cable, 9~Gm...
・・Gate circuit, IN1~■Nn・・・・Inverter.

Claims (1)

[Claims] 1. In a printed wiring board device in which a plurality of printed wiring board groups are connected to a main common signal bus and signals are exchanged between the main common signal bus and these printed wiring board groups, each of the printer wiring board groups a control printed wiring board connected to the main common signal bus through a connector that can be attached and detached by a mounting member; and a plurality of controlled printed wiring boards connected to the control printed wiring board through sub-common signal buses; On each of these control printed wiring boards, a switch means for generating a contact signal in conjunction with the attachment/detachment operation of the connector by the mounting member, and an electrical connection with the main common signal bus line is controlled in accordance with the contact signal of the switch means. a gate circuit for controlling the control printed wiring board, and prior to removing the connector from the control printed wiring board, close the gate circuit to cut off electrical connection between the main common signal bus and the control printed wiring board, and A printed wiring board device characterized in that after inserting the connector into the printed wiring board, the gate circuit is opened to establish electrical connection between the main common signal bus and the control printed wiring board.