JP2609445B2 - Bus line connector - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bus line connector suitable for transmitting control signals and the like between a plurality of devices.

[0002]

SUMMARY OF THE INVENTION The present invention provides a bus line connector for transmitting control signals and the like between a plurality of devices. When a connector plug is inserted into the connector socket, the impedance element connected between the lines of the connector socket is separated from the circuit. By doing so, a line impedance (terminating resistance) equivalent to the characteristic impedance is automatically inserted between the lines of the bus line connector of the terminal where the connector plug is not inserted, so that the standing wave (reflected wave) The generation is suppressed, and the waveform distortion of a control signal or the like to be transmitted is prevented.

[0003]

2. Description of the Prior Art Conventionally, digital information is preferably transmitted between two or more devices in a number of asynchronously operating devices coupled to the information bus via a single channel information bus. Communication system, each device comprises at least one digital data processing part having a clock generator for generating a periodic clock signal, which data processing part is processed by a digital control unit. A communication system for transmitting a control signal in a so-called differential mode in which a position switch and an information bus in a control unit are connected to a bus to form an AND gate circuit is disclosed in Japanese Patent Application Laid-Open No. 56-169452.

[0004]

In a communication system using such an information bus, if the characteristic impedance of the line is different from the impedance of the load, a standing wave (reflected wave) is generated and waveform distortion occurs. Therefore, in order to prevent this, it is necessary to insert a terminating impedance on the device side that is a terminal.

[0005] However, although there is a conventional method for preventing the generation of a standing wave by inserting a terminating impedance in a transmission line such as a feeder or a coaxial cable, an information bus (bus line) for transmitting a control signal or the like as described above. ) Has not yet been developed to prevent the generation of standing waves.

The present invention has been made in view of the above points, and it is possible to prevent a standing wave from being generated by automatically inserting a terminating impedance into a terminal device in a bus line for transmitting a control signal or the like. And a bus line connector.

[0007]

A bus line connector according to the present invention has at least two connection holes 4, 5 and a plurality of pins 6, 7 are erected in the connection holes 4, 5, respectively. The connector socket 1 in which the movable pieces of the switches 10 and 11 are formed so as to protrude upward or inward from the lower portions or the side walls of the connection holes 4 and 5, and the terminating impedance element 9 is connected to the switches 10 and 11. A connector plug 2 having a pair of connecting portions connected to the plurality of pins 6 and 7 at its ends;
When the connection portion of the connector plug 2 is inserted and connected to the connector, the movable pieces of the pair of switches 10 and 11 are pressed by the distal end portion of the connector plug 2 to separate the terminating impedance element 9 from the circuit.

An impedance element 9 is connected between the lines of the connector socket 1 via switches 10 and 11. Switches 10 and 11 are normally closed (normally closed). Therefore, when the connector plug 2 is not inserted into the connector socket 1, the switches 10 and 11 are turned on, and the impedance element 9 is connected between the lines. This state exists when the device to which the connector is attached becomes a terminal on the bus line.

On the other hand, when the connector plug 2 is inserted into the connector socket 1, the switches 10 and 11 are turned off, and the impedance element 9 connected between the lines is disconnected from the circuit. This state is when the device to which the connector is attached is located at an intermediate position other than the terminal on the bus line. In this manner, the impedance element 9 can be automatically opened and connected in accordance with insertion and removal of the connector plug.

[0010]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.
This will be described in detail with reference to FIG.

FIG. 1 shows an entire bus line connector according to the present invention. In FIG. 1, reference numeral 1 denotes a connector socket, and 2 denotes a connector plug. The socket 1 has two connection holes 4 and 5 on one side of the socket body 3 into which the plug 2 can be inserted.
This connection pins 6 _{through 65} and 7 _{1-7 5} are respectively implanted. These connection pins 6 _{through 65} and 7 _{1-7 5} are mounted on a printed circuit board 8 that is attached to the other side of the socket body 3 (back) the lower end thereof through the socket body 3, the circuit of FIG. 3 As can be seen from the figure, the connection pin 6 ₁
When the 7 _1, 6 ₂ and 7 _2, ..., 6 ₅ and 7 ₅ are respectively interconnected.

A resistor 9 is mounted on the printed circuit board 8 as an impedance element for termination.
One end is connected to the connecting pins 6 ₁ and 7 _1, the other end of the resistor 9 is connected to the switch 10 connected via a (see FIG. 3) and 11 pins 6 ₂ and 7 _2. The switches 10 and 11 are mounted so that the movable contact protrudes from the lower side walls of the connection holes 4 and 5 to the inside of the connection holes 4 and 5, and only the switch 11 is shown in FIG.

The switches 10 and 11 are normally closed switches in which the movable contacts are closed and are in an on state. Therefore, when the plug 2 is inserted into the connection hole 4 or 5 of the socket 1, the switch 10 or switch 10 or 11 opens the movable contact pushed by the 11 is turned off, thereby resistor 9 is connected pins 6 ₁ and 6 ₂ or 7 ₁
It comes to be released from between the 7 _second line. When the plug 2 is inserted, the off state of the switch 10 or 11 is maintained by the tapered portion on the side surface of the plug 2 and the engaging portion of the connector socket 1.

Further, 12 denotes a here plurality example a flat cable consisting of five bus lines, one end of which is mounted on the printed circuit board 8, the connecting pins 6 _{through 65} and 7 _1-7 socket 1 ₅ and each bus line is connected, and the other end is connected to the circuit of the device to which this connector is attached. Reference numeral 13 denotes a plurality of plugs 2
It is a flat cable that connects between them.

FIG. 2 shows a connection state of each device. For example, it is assumed that sockets 1A to 1D are respectively attached to first to fourth devices (none is shown). Plugs 2 connected to both ends of the flat cable 13A are provided in the lower connection hole of the socket 1A and the upper connection hole of the socket 1B.
A is inserted, plugs 2B connected to both ends of the flat cable 13B are inserted into the lower connection hole of the socket 1B and the upper connection hole of the socket 1C, and the lower connection hole of the socket 1C and the socket 1D are inserted. Plugs 2C connected to both ends of the flat cable 13C are inserted into the upper connection holes.

Thus, the first to fourth devices are connected in cascade. At this time, the switch at the connection hole where the plug is inserted is turned off and the line impedance is released, but the switch at the connection hole where the plug is not inserted remains on, so the line impedance is connected. It remains as it is. That is, the lower connection hole of the socket 1A, the socket 1
The switches at the upper and lower connection holes of B and 1C and the upper connection hole of the socket 1D are turned off to release the line impedance, but the upper connection hole of the socket 1A and the lower connection hole of the socket 1D are opened. Since the switch at the connection hole remains on, the line impedance remains connected. As a result, the terminal is substantially terminated by the line impedance, the occurrence of standing waves is prevented, and problems such as waveform distortion are solved.

FIG. 3 shows an example of a transmission system using the bus line connector according to the present invention. In FIG. 3, parts corresponding to those in FIG. In the figure, reference numeral 20 denotes a device such as a tuner,
20 'is a device such as a deck. Here, the circuit configurations of the devices 20 and 20 'have exactly the same configuration. Therefore, in the device 20', parts corresponding to the device 20 are indicated by dashes, and detailed description thereof is omitted.

The connecting pin 6 _{through 65} and 7 _{1-7 5,} further resistor 9, the connection relationship of the switch 10, 11 is as described above. Here, the connection pins 6 ₁ , 6 ₂ and 7 ₁ , 7 ₂
The line is used as a line for transmitting a control signal, connecting pins 6 ₃ and 7 ₃ of the line is used as earth line, further connecting pin 6 _4, 6 ₅ and 7 _4, 7 ₅ line power supply lines or audio Used as a signal line.
And here connecting pins 6 _{through 65} and connection pins 6 ₁ '
6 ₅ '20 and the device 20 is connected to' intended to be transmitted state to each other.

Reference numeral 21 denotes an input terminal to which a command signal (logic signal) for transmission from, for example, a microcomputer is supplied. From this input terminal 21, a high state signal, for example, 0 "is supplied to the current switches 22 and 23. Then, the current switches 22 and 23 are turned on and the connection pin 6 ₁
And a predetermined value, for example, 120 mV or more voltage is generated between the 6 _2,
This is supplied to the device 20 'as a control signal. Further, when the signal of a low state, for example, 1 "from the input terminal (21) is supplied to the current switch 22 and 23, a predetermined value, for example less than 20mV between the connection pins 6 ₁ and 6 ₂ current switches 22 and 23 are turned off Is generated and supplied to the device 20 'as a control signal.

Further, at the time of receiving a predetermined value, for example, 120 mV at a high state between from device 20 'connecting pins 6 ₁ and 6 ₂
The above voltage is supplied, and in the low state, a predetermined value, for example,
Voltages of 20 mV or less are supplied. These voltages are supplied to the differential amplifier 24 as control signals, and a reception output is obtained at an output terminal 25. The resistors 26 and 27 and the power supply 28 set the bias condition to an intermediate value of the voltage generated at both ends of the resistor 9.

[0021] Also in this case the connecting pins 6 _{through 65} of the resistor 9 switch 10 since the plug is inserted is turned off on the socket side is opened from between the connecting pins 6 ₁ and 6 ₂ of the line, since the socket end of the connecting pin 7 _{1-7 5} plug is not inserted nothing, the resistor 9 switch 11 is turned on is connected between the connection pin 7 _{1-7 5} line, yet the connection pin 7 _{1-7 5} and the connecting pins 6 _{through 65} each other also will be a resistor 9 is connected between the end connecting pins 6 ₁ and 6 ₂ of the line because it is connected to each other, this results terminal The device 20 is terminated to prevent the generation of a standing wave, and no waveform distortion occurs.

FIG. 4 shows an example of a specific configuration (lock type) of the switches 10 and 11 mounted behind the socket body 3. As shown in FIG. The switch 10 is a fixed contact 10a
And a movable contact 10b and a sliding member 10c. When the plug 2 (FIG. 1) is inserted into the connection hole 4, the sliding member 10c is pushed by the tip of the plug 2 and moves in the direction of the arrow. The movable contact 10b moves and the fixed contact 10a
The switch 10 is turned off. The same applies to the case of the switch 11. The switch 11 includes a fixed contact 11a, a movable contact 11b, and a sliding member 11c. When the plug 2 (FIG. 1) is inserted into the connection hole 5, it slides by the tip of the plug 2. The member 11c is pushed and moves in the direction of the arrow, whereby the movable contact 11b moves and moves away from the fixed contact 11a, and as a result, the switch 11 is turned off.

FIG. 5 shows another example of the specific configuration (lock type) of the switches 10 and 11 mounted behind the socket body 3. As shown in FIG. The switch 10 is a fixed contact 10
a, a movable contact 10b, and a sliding member 10c,
When the plug 2 (FIG. 1) is inserted into the connection hole 4, the plug 2
The sliding member 10c is pushed by the tip of the movable contact 10c and moves in the direction of the arrow, whereby the movable contact 10b moves and the fixed contact 10c moves.
a, so that the switch 10 is turned off. The same applies to the case of the switch 11. The switch 11 includes a fixed contact 11a, a movable contact 11b, and a sliding member 11c. When the plug 2 (FIG. 1) is inserted into the connection hole 5, it slides by the tip of the plug 2. The member 11c is pushed and moves in the direction of the arrow, whereby the movable contact 11b moves and moves away from the fixed contact 11a, and as a result, the switch 11 is turned off.

FIG. 6 shows still another example of the specific configuration (lock type) of the switches 10 and 11 mounted behind the socket body 3. As shown in FIG. The switch 10 includes a fixed contact 10a, a movable contact 10b, and a sliding member 10c. When the plug 2 (FIG. 1) is inserted into the connection hole 4, the sliding member 10c is pushed by the tip of the plug 2 and is indicated by an arrow. , Whereby the movable contact 10b moves and moves away from the fixed contact 10a, so that the switch 10 is turned off. The same applies to the case of the switch 11, which includes a fixed contact 11a, a movable contact 11b, and a sliding member 11c. When the plug 2 (FIG. 1) is inserted into the connection hole 5,
The sliding member 11c is pushed by the tip of the plug 2 and moves in the direction of the arrow, whereby the movable contact 11b moves and moves away from the fixed contact 11a, and as a result, the switch 11 is turned off.

FIG. 7 shows still another specific configuration (push type or slide type) of the switch 10 or 11. If the switch 10 is used now, this switch 1
Numeral 0 denotes two fixed contacts 10a which are planted on the printed circuit board 8 and have a predetermined gap at the ends thereof, and a movable contact 10b fitted in the gap of the fixed contact 10a and capable of moving back and forth. The movable contact 10b is fixed and includes a sliding member 10c which moves left and right in accordance with insertion and removal of a plug, a coil spring 10d provided between the sliding member 10c and the printed circuit board 8, and a case 10e.

When the plug is not inserted into the socket, the sliding member 10c moves to the left due to the elasticity of the coil spring 10d, and the movable contact 10b shorts both fixed contacts 10a across the gap as shown in FIG.
Is turned on, but when the plug is inserted into the socket, the sliding member 10c moves to the right against the elastic force of the coil spring 10d by the tip of the plug, and the movable contact 10b passes through the gap. One fixed contact 1
0a side only, and as a result, switch 1
0 turns off.

FIG. 8 schematically shows a state in which a switch having the structure shown in FIG. 7 is incorporated in a socket. In a state where a plug is not inserted into the connection hole 4 (or 5), the sliding member 10 is inserted.
c (or 11c) is pushed leftward in the drawing by the elastic force of the coil spring 10d, and the fixed contact 10a (or 11a) and the movable contact 10b (or 11b) come in contact with each other to turn on the switch 10, and the resistor 9 is in a state of being connected between the lines of the connection pins 6 (or 7). When the plug is inserted into the connection hole 4 (or 5), the sliding member 10c (or 11c) is moved by the tip of the plug to the coil spring 10d. The fixed contact 10a (or 1) is pushed to the right side in the drawing against the elastic force.
The movable contact 10b (or 11b) is separated from 1a), the switch 11 is turned off, and the resistor 9 is opened from between the lines of the connection pin 6 (or 7).

[0028]

As described above, according to the present invention, when the connector plug is inserted into the connector socket, the impedance element connected between the lines of the connector socket is cut off from the circuit. The terminal line impedance equivalent to the characteristic impedance is automatically inserted between the lines of the bus line connector to suppress the generation of standing waves (reflected waves).
Waveform distortion of a control signal or the like to be transmitted is prevented.

Further, since the terminating impedance element is built in the bus line connector, it is not necessary to connect each one externally, it is easy to handle, and it is not necessary to be aware of the presence of the terminating line impedance. When the device becomes a terminal, the terminal line impedance can be automatically inserted.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an embodiment of the present invention.

FIG. 2 is a connection diagram of a bus line connector according to the present invention.

FIG. 3 is a transmission system diagram to which the bus line connector according to the present invention is applied.

FIG. 4 is a rear view showing an example of a main part of the present invention.

FIG. 5 is a rear view showing another example of the main part of the present invention.

FIG. 6 is a rear view showing still another example of the main part of the present invention.

FIG. 7 is an internal structural diagram showing still another example of the main part of the present invention.

FIG. 8 is a schematic diagram of the incorporation of the essential parts of FIG.

[Explanation of symbols]

1 connector socket, 2 connector plug, 9
Resistor (impedance element), 10, 11 switch

Claims (5)

(57) [Claims] 1. A switch having at least two connection holes, a plurality of pins being respectively erected in the connection holes, and movable pieces of a pair of switches projecting upward or inward from lower portions or side wall portions of the connection holes. A connector socket formed and having a terminating impedance element connected to the switch; and a connector plug having a pair of connecting portions connected to the plurality of pins at an end, wherein the connector is provided at a pin of the connection hole. A bus line connector, characterized in that the movable pieces of the pair of switches are pressed by the distal ends of the connector plugs when the connecting portions of the plugs are inserted and connected, thereby disconnecting the terminating impedance element from the circuit. 2. A plurality of pairs of said connector plugs are connected to each other by a control cable with respect to said connector socket, and both ends of each end of said plurality of pairs of connector plugs are connected to both sides of said connector socket. When inserted into the holes, both of the pair of switches are controlled to control the impedance element to be opened from between control signal bus lines connected by the control cable. Item 2. The bus line connector according to Item 1. 3. The bus line connector according to claim 1, wherein a lock switch is used as the switch. 4. The bus line connector according to claim 1, wherein a slide switch is used as the switch. 5. The bus line connector according to claim 1, wherein a push-type switch is used as the switch.