Patent Description:
In the industrial multi-axis control device, motor control is performed by feeding back a signal detected by a slave device such as an encoder or a sensor to a master device.

<CIT>
discloses a communication system, comprising: a master device; a superordinate trunk cable connected to the master device; a superordinate slave device connected to the master device via the superordinate trunk cable; a subordinate trunk cable connected superordinate slave device and an subordinated slave device; wherein via the superordinated trunk cable and the subordinated trunk cable both, power and signals, are transmitted. Further communication systems are known from "<NPL>), <CIT>, and <CIT>.

However, in the conventional industrial multi-axis control device, a master device is connected to a signal line and a power line on a one-to-one basis. Therefore, in the conventional industrial multi-axis control device, a plurality of wires is scattered between the master device and the plurality of slave devices, and a space is required for wiring. Further, since disconnection protection is required for wiring to the movable portion, the movable range of the movable portion is limited.

Further, in the conventional industrial multi-axis control device, there is a problem that maintainability is poor because a plurality of wires is scattered as described above.

Therefore, the present disclosure has been made in view of the above-described problem, and an object of the present disclosure is to provide a communication system capable of realizing reduction in size and improvement in maintainability of equipment in an industrial multi-axis control device.

The present invention provides a communication system according to independent claim <NUM>. The dependent claims show further embodiments of the said communication system.

According to the present disclosure, it is possible to provide the communication system capable of realizing reduction in size and improvement in maintainability of equipment in the industrial multi-axis control device.

Hereinafter, an embodiment will be described with reference to <FIG>.

An example of a configuration of a communication system <NUM> according to the present embodiment will be described with reference to <FIG>.

As illustrated in <FIG>, the communication system <NUM> according to the present embodiment includes a master device <NUM>, a plurality of slave devices <NUM> (in the present embodiment, three slave devices <NUM>#<NUM> to <NUM>#<NUM>), trunk cables 21A/22A/25A, and a connector 40A.

In the present embodiment, as shown in <FIG>, the master device <NUM> and the plurality of slave devices <NUM>#<NUM> to <NUM>#<NUM> are connected by daisy chain connection. In the present embodiment, a case where the number of slave devices <NUM> is three is described as an example, but the present disclosure is not limited to such a case.

In the relationship between the slave device <NUM>#<NUM> and the slave device <NUM>#<NUM> in the present disclosure, the slave device <NUM>#<NUM> is a superordinate slave device and the slave device <NUM>#<NUM> is a subordinate slave device. In this case, the trunk cable 21A becomes the superordinate trunk cable 21A and the trunk cable 22A becomes the subordinate trunk cable 22A.

Similarly, in the relationship between the slave device <NUM>#<NUM> and the slave device <NUM>#<NUM>, the slave device <NUM>#<NUM> is the superordinate slave device, and the slave device <NUM>#<NUM> is the subordinate slave device <NUM>. In this case, the trunk cable 22A becomes the superordinate trunk cable 21A and the trunk cable 25A becomes the subordinate trunk cable 22A.

Hereinafter, in the present embodiment, for convenience of description, the slave device <NUM>#<NUM> is referred to as a "superordinate slave device <NUM>", and the slave device <NUM>#<NUM> is referred to as a "subordinate slave device <NUM>".

The master device <NUM> is the servo amplifier, and each of the slave devices <NUM>#<NUM> to <NUM>#<NUM> is any one of an encoder and a sensor. Here, the encoder includes an encoder included in a servo motor and an encoder used as a type of sensor.

For example, the master device <NUM> is a servo amplifier <NUM>, the slave device <NUM>#<NUM> may be a first encoder, the slave device <NUM>#<NUM> may be a second encoder, and the slave device <NUM>#<NUM> may be a sensor.

Alternatively, the master device <NUM> may be a first encoder, the slave device <NUM>#<NUM> may be a second encoder, the slave device <NUM>#<NUM> may be a third encoder, and the slave device <NUM>#<NUM> may be a sensor.

The trunk cable 21A (superordinate trunk cable) is connected to the master device <NUM> and the connector 40A. To be more specific, the trunk cable 21A is connected to the master device <NUM> via the connector <NUM>, and is connected to the slave device <NUM>#<NUM> (superordinate slave device) via the connector 40A.

The slave device <NUM>#<NUM> is connected to the master device <NUM> via at least the trunk cable 22A and the connector 40A. To be more specific, the slave device <NUM>#<NUM> is connected to the master device <NUM> via the connector 40A, the trunk cable 22A, and the connector <NUM>.

The trunk cable 22A (subordinate trunk cable) is connected to two connectors 40A. To be more specific, the trunk cable 22A is connected to the slave device <NUM>#<NUM> and the slave device <NUM>#<NUM> (subordinate slave device) via each of the two connectors 40A.

The slave device <NUM>#<NUM> is connected to the slave device <NUM>#<NUM> via at least the trunk cable 22A and the connector 40A. The slave device <NUM>#<NUM> is connected to the slave device <NUM>#<NUM> via at least the trunk cable 25A and the connector 40A.

As shown in <FIG>, the connector 40A includes a superordinate power line 41A, a superordinate signal line 43A, a subordinate signal line 44A, and a power branching unit 45A. The connector 40A may further include a standby power line 42A and a power branching unit 46A.

In the present embodiment, a case in which the superordinate power line 41A, the standby power line 42A, the superordinate signal line 43A, and the subordinate signal line 44A are configured by one pair is described as an example, but the present disclosure is not limited to such a case, and is also applied to a case in which the superordinate power line, the standby power line, the superordinate signal line, and the subordinate signal line are configured by an arbitrary number of pairs.

The superordinate power line 41Ais to transmit power supplied from the master device <NUM> side, and the standby power line 42A is to transmit power transmitted from a power supply unit <NUM> (see <FIG> and <FIG>) described later.

The superordinate signal line 43Ais used to transmit communication between the master device <NUM> and the slave device <NUM>#<NUM>, and the subordinate signal line 44A is used to transmit communication between the slave device <NUM>#<NUM> and the slave device <NUM>#<NUM>. The superordinate signal line 43A and the subordinate signal line 44A are electrically disconnected from each other in the connector 40A.

The power branching unit 45A branches the superordinate power line 41A into a first power line 41A1 directed toward the slave device <NUM>#<NUM> and a second power line 41A2 directed toward the slave device <NUM>#<NUM>.

The power branching unit 46A branches the standby power line 42Ainto a first standby power line 42A1 directed toward the slave device <NUM>#<NUM> and a second standby power line 42A2 directed toward the slave device <NUM>#<NUM>.

As shown in <FIG>, the connector 40A includes a first connecting unit <NUM>, a second connecting unit <NUM>, and a third connecting unit <NUM>.

The first connecting unit <NUM> is connected to the slave device <NUM>#<NUM> (superordinate slave device), the second connecting unit <NUM> is connected to the first connecting unit <NUM> and the trunk cable 21A, and the third connecting unit <NUM> is connected to the first connecting unit <NUM> and the trunk cable 22A.

As shown in <FIG> and <FIG>, the trunk cable 21A includes a superordinate power line 41A and a superordinate signal line 43A. The trunk cable 21A may further include a standby power line 42A.

As shown in <FIG> and <FIG>, the trunk cable 22A includes a second power line 41A2 and a subordinate signal line 44A. The trunk cable 22A may further include a standby power line 42A (second standby power line 42A2).

The first connecting unit <NUM> includes a power branching unit 45A, a superordinate power line 41A (a first power line 41A1 and a second power line 41A2), a superordinate signal line 43A, and a subordinate signal line 44A. The first connecting unit <NUM> may further include a power branching unit 46A and a standby power line 42A (a first standby power line 42A1 and a second standby power line 42A2).

The slave device <NUM>#<NUM> includes a signal processing circuit <NUM>, a communication circuit <NUM>, a PHY33A, a PHY33B, and a power supply circuit <NUM>.

The PHY33A transmits and receives electrical signals via the superordinate signal line 43A, and the PHY33B transmits and receives electrical signals via the superordinate signal line 43A.

The communication circuit <NUM> converts an electric signal received from the PHY33A/PHY33B into a communication signal and transmits the communication signal to the signal processing circuit <NUM>, and converts a communication signal received from the signal processing circuit <NUM> into an electric signal and transmits the electric signal to the PHY33A/PHY33B.

The signal processing circuit <NUM> performs signal processing on the communication signal received from the communication circuit <NUM>. The power supply circuit <NUM> supplies power via the superordinate power line 41A and the standby power line 42A.

An example of the configuration of the communication system <NUM> according to the present embodiment will be described with reference to <FIG>, focusing on differences from the configuration of the communication system <NUM> according to the first embodiment described above.

As illustrated in <FIG>, the communication system <NUM> according to the present embodiment includes a master device <NUM>, a plurality of slave devices <NUM> (three slave devices <NUM>#<NUM> to <NUM>#<NUM> in the present embodiment), trunk cables 21B/22B/25B, branch cables 23B, and connectors 40B/<NUM>.

In the present embodiment, as shown in <FIG>, the master device <NUM> and the plurality of slave devices <NUM>#<NUM> to <NUM>#<NUM> are connected by T-branch connection. The T-shaped branch connection is used when the slave device <NUM> is separated from the trunk cables 21B/22B/25B. In the present embodiment, a case where the number of slave devices <NUM> is three is described as an example, but the present disclosure is not limited to such a case.

As shown in <FIG>, the connector 40B includes a first connecting unit <NUM>, a second connecting unit <NUM>, a third connecting unit <NUM>, and a fourth connecting unit <NUM>.

The second connecting unit <NUM> is connected to the first connecting unit <NUM> and the trunk cable 21B, the third connecting unit <NUM> is connected to the first connecting unit <NUM> and the trunk cable 22B, and the fourth connecting unit <NUM> is connected to the first connecting unit <NUM> and the branch cable 23B extending toward the slave device <NUM>#<NUM>.

As shown in <FIG> and <FIG>, the trunk cable 21B includes a superordinate power line 41B and an superordinate signal line 43B. The trunk cable 21B may further include a standby power line 42B.

As shown in <FIG> and <FIG>, the trunk cable 22B includes a second power line 41B2 and a subordinate signal line 44B. The trunk cable 22B may further include a standby power line 42A (second standby power line 42B2).

As shown in <FIG> and <FIG>, the branch cable 23B includes a superordinate power line 41B (first power line 41B1), a superordinate signal line 43B, and a subordinate signal line 44B. The branch cable 23B may further include a standby power line 42A (second standby power line 42B2).

The first connecting unit <NUM> includes a power branching unit 45B, a superordinate power line 41B (a first power line 41B1 and a second power line 41B2), a superordinate signal line 43B, and a subordinate signal line 44B. The first connecting unit <NUM> may further include a power branching unit 46B and a standby power line 42B (a first standby power line 42B <NUM> and a second standby power line 42B2).

Hereinafter, the configuration of the external power supply in the communication system <NUM> according to the present embodiment will be described with reference to <FIG> and <FIG>.

As shown in <FIG> and <FIG>, the communication system <NUM> according to the present embodiment further includes a power source unit <NUM> disposed between the master device <NUM> and the connector 40A/40B.

The power source unit <NUM> includes a power supply circuit <NUM> and a power supply unit <NUM>. The power supply circuit <NUM> supplies power via the superordinate power lines 41A/41B. The power supply unit <NUM> supplies power via the standby power lines 42A/42B as a standby power supply when the power supply capacity of the power supply circuit <NUM> is insufficient. For example, the power supply unit <NUM> may be a battery.

In addition, the power source unit <NUM> includes a standby power line 42A/42B that transmits power transmitted from the power supply unit <NUM>, and superordinate signal lines 21A/21B.

As shown in <FIG>, the power source unit <NUM> may be provided outside the master device <NUM> and connected to the master device <NUM> via the connector <NUM>, the cable <NUM>, and the connector <NUM>.

Alternatively, as shown in <FIG>, the power source unit <NUM> may be provided inside the master device <NUM>.

The master device <NUM> includes a signal processing circuit <NUM>, a communication circuit <NUM>, and a PHY13. PHY13 transmits and receives electrical signals via superordinate signal lines 43A/43B. The communication circuit <NUM> converts an electric signal received from the PHY13 into a communication signal and transmits the communication signal to the signal processing circuit <NUM>, and converts a communication signal received from the signal processing circuit <NUM> into an electric signal and transmits the electric signal to the PHY13. The signal processing circuit <NUM> performs signal processing on the communication signal received from the communication circuit <NUM>.

Hereinafter, the maintenance connector <NUM> used in the communication system <NUM> according to the present embodiment will be described with reference to <FIG> and <FIG>. <FIG> shows an example of the structure and connection configuration of the maintenance connector <NUM> used in the communication system <NUM> according to the first embodiment, and <FIG> shows an example of the structure and connection configuration of the maintenance connector <NUM> used in the communication system <NUM> according to the second embodiment.

As shown in <FIG> and <FIG>, the maintenance connector <NUM> is connected to the first connecting unit <NUM> of the connector 40A or the first connecting unit <NUM> of the connector 40B. The maintenance connector <NUM> has a signal line connecting unit 47A/47B that connects the superordinate signal lines 43A/43B and the subordinate signal lines 44A/44B.

As described above, the communication system <NUM> according to the present embodiment includes the master device <NUM>, the trunk cables 21A/21B, the connectors 40A/40B, the slave device <NUM>#<NUM>, the trunk cables 22A/22B, and the slave device <NUM>#<NUM>. The connectors 40A/40B include the superordinate power lines 41A/41B, the power branching units 45A/45B, the superordinate signal line 43A, and the subordinate signal line 44A.

According to such a configuration, since the power to the subordinate slave device (the slave device <NUM>#<NUM> or the slave device <NUM>#<NUM>) is not insulated even in a case that the superordinate slave device <NUM> (the slave device <NUM>#<NUM>) is broken and disconnected, the recovery work of the failed superordinate slave device <NUM> (the slave device <NUM>#<NUM>) can be performed in a state in which the power is supplied to the subordinate slave device.

Further, in the communication system <NUM> according to the present embodiment, the connectors 40A/40B may include the first connecting unit <NUM>, the second connecting unit <NUM>, and the third connecting unit <NUM>. The trunk cable 21A may include the superordinate power line 41A and the superordinate signal line 43A. The trunk cable 22A may include the second power line 41A2 and the lower signal line 44A. The first connecting unit <NUM> may include the power 45A. According to such a configuration, it is possible to realize daisy chain connection that is capable of giving a degree of freedom to the configuration of the slave device <NUM> to be connected by using a general-purpose wiring method.

In the communication system <NUM> according to the present embodiment, the connectors 40A/40B may include the first connecting unit <NUM>, the second connecting unit <NUM>, the third connecting unit <NUM>, and the fourth connecting unit <NUM>, the trunk cable 21B may include the superordinate power line 41B and the superordinate signal line 43B, the trunk cable 22B may include the second power line 45B1 and the subordinate signal line 44B, the branch cable 23B may include the first power line 45B1, the superordinate signal line 43B, and the subordinate signal line 44B, and the first connecting unit <NUM> may include the power branching unit 45B. According to such a configuration, it is possible to realize a T-shaped branch connection that is capable of giving a degree of freedom to the configuration of the slave device <NUM> to be connected by using a general-purpose wiring method.

The communication system <NUM> according to the present embodiment may further include the power source unit <NUM>, and the power source unit <NUM> may further include the power supply unit <NUM>, the standby power lines 42A/42B, and the superordinate signal lines 43A/43B.

According to such a configuration, even when the power supply capacity of the master device <NUM> is insufficient or a plurality of different power supplies are required, power (standby power) can be supplied from the power source unit <NUM> as well. Therefore, the slave device <NUM> to be connected can have versatility.

In the communication system <NUM> according to the present embodiment, the connectors 40A/40B may further include power branching units 46A/46B. According to such a configuration, when the superordinate slave device <NUM> (slave device <NUM>#<NUM>) is broken and disconnected, not only the power to the subordinate slave device <NUM> (slave device <NUM>#<NUM>) but also the standby power is not insulated, and therefore the recovery work of the failed superordinate slave device (the slave device <NUM>#<NUM>) can be performed in a state in which the power and standby power is supplied to the subordinate slave device (slave device <NUM>#<NUM>).

In the communication system <NUM> according to the present embodiment, the master device <NUM> is the servo amplifier, and each of the slave devices <NUM>#<NUM> to <NUM>#<NUM> is any one of an encoder and a sensor. According to this configuration, in a machine such as a robot, the movable range of the machine can be expanded by saving wiring. Since power can also be supplied to the servo motor and the encoder as the subordinate slave device <NUM> when the servo motor and the encoder as the superordinate slave device <NUM> are replaced, it becomes unnecessary to correct the positional deviation at the time of restoration, thereby improving the usability of the entire robot and shortening the restoration work.

Further, in the communication system <NUM> according to the present embodiment, the connectors 40A/40B include superordinate power lines 41A/41B, power branching units 45A/45B, superordinate signal lines 43A/43B for transmitting communication data between the master device <NUM> side and the maintenance connector <NUM> side, and subordinate signal lines 44A/44B for transmitting communication data between the maintenance connector <NUM> side and the slave device <NUM>#<NUM> side. The maintenance connector <NUM> includes signal line connecting units 47A/47B to connect the superordinate signal lines 42A/43B and the subordinate signal lines 44A/44B. According to such a configuration, even in a state where the specific slave device <NUM>#<NUM> is disconnected, it is possible to continue communication between the master device <NUM> and the other slave devices <NUM><NUM>#<NUM>/<NUM><NUM>#<NUM>.

Claim 1:
A communication system (<NUM>) comprising:
a connector (40A, 40B);
a master device (<NUM>);
a superordinate trunk cable (21A, 21B) connected to the master device (<NUM>);
a superordinate slave device (<NUM>#<NUM>) connected to the master device (<NUM>) via the superordinate trunk cable (21A, 21B) and the connector (40A, 40B);
a subordinate trunk cable (22A, 22B) connected to the connector (40A, 40B); and
a subordinate slave device (<NUM>#<NUM>) connected to the superordinate slave device (<NUM>#<NUM>) via the subordinate trunk cable (22A, 22B) and the connector (40A, 40B),
the connector (40A, 40B) comprising:
a superordinate power line (41A, 41B) via which power that is supplied from the master device (<NUM>) is transmitted,
a power branching unit (45A, 45B) configured to branch power supplied from the master device (<NUM>) into a first power line (41A1, 41B1) toward the superordinate slave device (<NUM>#<NUM>) and a second power line (41A2, 41B2) toward the subordinate slave device (<NUM>#<NUM>);
a superordinate signal line (43A, 43B) via which communication between the master device (<NUM>) and the superordinate slave device (<NUM>#<NUM>) is transmitted; and
a subordinate signal line (44A, 44B) which is insulated from the superordinate signal line (43A, 43B) and via which communication between the superordinate slave device (<NUM>#<NUM>) and the subordinate slave device (<NUM>#<NUM>) is transmitted;
wherein
the master device (<NUM>) is a servo amplifier, and
each of the superordinate slave device (<NUM>#<NUM>) and the subordinate slave device (<NUM>#<NUM>) is any one of an encoder and a sensor.