U.S. patent application number 11/719365 was filed with the patent office on 2011-06-09 for method and apparatus for a hub in daisy chain configuration.
Invention is credited to Jan Olof Andersson, Logan Brent Grauer, Chris Edwin Kasian, Robert Christopher Kwong, Jason John Lemon, Kenneth John Lockhart, Glenn William Nichols, William Andrew Perrin, Trevor Lewis Rossner, Jeffrey Paul Wiedemann.
Application Number | 20110134792 11/719365 |
Document ID | / |
Family ID | 44081911 |
Filed Date | 2011-06-09 |
United States Patent
Application |
20110134792 |
Kind Code |
A1 |
Andersson; Jan Olof ; et
al. |
June 9, 2011 |
Method and Apparatus for a Hub in Daisy Chain Configuration
Abstract
A connector hub comprising a number of cable interfaces is used
to allow a number of network devices connected to a network to be
connected in a free-form manner, yet still maintain a daisy chain
configuration. A cable comprising at least two conductors, wherein
the conductors are preferably a twisted pair of copper wire, is
used to connect each of the network devices to a cable interface on
the connector hub, so that each network device only has a single
cable connected to it. The connector hub connects a master or
primary network device to the network devices connected by a cable
to the cable interfaces of the connector in a daisy chain
configuration.
Inventors: |
Andersson; Jan Olof; (Apple
Valley, MN) ; Lockhart; Kenneth John; (Surrey,
CA) ; Rossner; Trevor Lewis; (Surrey, CA) ;
Wiedemann; Jeffrey Paul; (Apple Valley, MN) ; Grauer;
Logan Brent; (Regina, CA) ; Kasian; Chris Edwin;
(Rrgina, CA) ; Perrin; William Andrew; (Surrey,
CA) ; Kwong; Robert Christopher; (Surrey, CA)
; Nichols; Glenn William; (Surrey, CA) ; Lemon;
Jason John; (Regina, CA) |
Family ID: |
44081911 |
Appl. No.: |
11/719365 |
Filed: |
December 17, 2004 |
PCT Filed: |
December 17, 2004 |
PCT NO: |
PCT/US2004/042931 |
371 Date: |
December 15, 2010 |
Current U.S.
Class: |
370/254 |
Current CPC
Class: |
H04L 12/2838 20130101;
H04L 2012/285 20130101; H04L 12/44 20130101; Y10T 29/49117
20150115 |
Class at
Publication: |
370/254 |
International
Class: |
H04L 12/28 20060101
H04L012/28 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 19, 2004 |
US |
PCT/US2004/038992 |
Claims
1. A master network device for creating a network in a daisy chain
configuration, the master network device comprising: a network
component configured to operate on a daisy chain network and
comprising an output port and an input port for connection to the
daisy chain network; and a connector hub operative to connect a
plurality of network devices in a daisy chain network with cables,
wherein each cable comprises two conductors, the connector hub
comprising: a plurality of sequential cable interfaces including a
first cable interface and a last cable interface, each cable
interface comprising a pair of conductor connectors, each conductor
connector operative to connect one conductor of a connected cable
to a connecting circuit; wherein the connecting circuit is
configured such that: one of the conductor connectors of the first
cable interface is connected to the output port of the network
component and the other of the conductor connectors of the first
cable interface is connected to one of the conductor connectors of
a next cable interface; the other of the conductor connectors of
the next cable interface is connected to one of the conductor
connectors of a succeeding cable interface, and conductor
connectors of the subsequent succeeding cable interfaces are
connected sequentially in the same manner; and the other of the
conductor connectors of the last cable interface is connected to
the input port of the network component.
2. The device of claim 1 wherein each conductor connector of each
cable interface is operative to connect to a conductor that is a
twisted wire pair.
3. The device of claim 1 wherein at least one of the cable
interfaces is operative to connect to a category 5 cable.
4. The device of claim 1 wherein at least one cable interface
comprises a socket adapted to receive a plug attached to an end of
a cable, and wherein inserting the plug into the socket connects
the conductors of the cable to the conductor connectors of the at
least one cable interface.
5. The device of claim 4 wherein the plug and socket conform to the
RJ45 standard.
6. The system of claim 1 wherein the network component is
configured to operate on a network using the RS 485 standard.
7. The device of claim 1 wherein the network component comprises a
second network connection operative to connect to a second network
and the network component is operative to act as bridge from the
second network to the daisy chain network.
8. The device of claim 7 wherein the network connection is an
Ethernet connection.
9. The device of claim 7 wherein the network connection is a
wireless connection.
10. The device of claim 7 wherein the network connection is an
internet connection.
11. A daisy chain network comprising a master network device
according to claim 1, and at least two network devices, wherein:
each network device is operative to communicate as a node in a
daisy chain network; and each network device is operatively
connected by a cable to a cable interface of the master network
device.
12. The network of claim 11 wherein each of the cable interfaces of
the master network device not connected to a cable has a shorting
plug inserted in the cable interface.
13. A daisy chain network comprising a master network device
according to claim 1, and at least two network devices, wherein:
each network device is operative to communicate as a node in a
daisy chain network; each network device is operatively connected
by a cable to one of a cable interface of the master network device
and a connector device; and wherein each cable interface of each
connector device is connected by a cable to one of a network device
and another connector device.
14. The network of claim 13 wherein each of the cable interfaces of
the master network device not connected to a cable has a shorting
plug inserted in the cable interface.
15. A connector hub to connect a plurality of network devices in a
daisy chain network with cables, wherein each cable comprises two
conductors, the connector hub comprising: a connecting circuit; a
primary network device interface comprising a pair of conductor
connectors, each conductor connector operative to connect a
conductor to the connecting circuit; and a plurality of sequential
cable interfaces including a first cable interface and a last cable
interface, each cable interface comprising a pair of conductor
connectors, each conductor connector operative to connect one
conductor of a connected cable to the connecting circuit; wherein
the connecting circuit is configured such that: one of the
conductor connectors of the first cable interface is connected to
one of the conductor connectors of the primary network device
interface and the other of the conductor connectors of the first
cable interface is connected to one of the conductor connectors of
a next cable interface and the other of the conductor connectors of
the next cable interface is connected to one of the conductor
connectors of a succeeding cable interface; conductor connectors of
the subsequent succeeding cable interfaces are connected
sequentially in the same manner; and the other of the conductor
connectors of the last cable interface is connected to the other
conductor connector of the primary network device interface.
16. The device of claim 15 wherein each conductor connector of each
cable interface is operative to connect to a conductor that is a
twisted wire pair.
17. The device of claim 15 wherein at least one of the cable
interfaces is operative to connect to a category 5 cable.
18. The device of claim 15 wherein at least one cable interface
comprises a socket adapted to receive a plug attached to an end of
a cable, and wherein inserting the plug into the socket connects
the conductors of the cable to the conductor connectors of the at
least one cable interface.
19. The device of claim 18 wherein the plug and socket conform to
the RJ45 standard.
20. The system of claim 15 wherein the network component is
configured to operate on a network using the RS 485 standard.
21. A daisy chain network comprising: a connector hub according to
claim 15; a primary network device; and at least two network
devices, wherein: the primary network device and each network
device are operative to communicate as a node in a daisy chain
network; the primary network device is operatively connected to the
primary network device interface of the connector hub; and each
network device is operatively connected by a cable to a cable
interface of the connector device.
22. The network of claim 21 wherein each of the cable interfaces of
the connector hub not connected to a cable has a shorting plug
inserted in the cable interface.
23. A daisy chain network comprising: a connector hub according to
claim 15; a primary network device; and at least two network
devices, wherein: the primary network device and each network
device are operative to communicate as a node in a daisy chain
network; the primary network device is operatively connected to the
primary network device interface of the connector hub; each network
device is operatively connected by a cable to one of a cable
interface of the master network device or a connector device; and
wherein each cable interface of each connector device is connected
by a cable to one of a network device and another connector
device.
24. The network of claim 23 wherein each of the cable interfaces of
the master network device not connected to a cable has a shorting
plug inserted in the cable interface.
Description
[0001] This invention is in the field of network connector devices
and more specifically systems for connecting networks in a daisy
chain configuration.
BACKGROUND
[0002] Daisy chaining is the simplest way to connect a network.
Devices connected by a daisy chain are connected one to another in
series and a message that is sent on the network has to travel down
the chain from one device to another. Compared to other network
topologies, daisy chaining is relatively slow, however in
applications that do not require large amounts of data transfer and
fast transfer rates, daisy chaining is a common practice and daisy
chain networks are common in industrial control networks.
[0003] One common standard that uses a daisy chain configuration
for networking devices is the RS-485 standard. While RS-485 devices
may be quite common, there are other protocols that specify or can
use a daisy chain network configuration such as Apple's
LocalTalk.TM. and many types of industrial applications.
[0004] While networked devices using the RS-485 protocol have
always been common in industrial systems, such as larger scale heat
and ventilation systems, with the decrease in price of control
systems, smaller scale control systems are becoming more common.
One area using networked devices that can use a daisy chain
topology is home automation and especially home HVAC systems.
[0005] In order to setup devices in a daisy chain network, a cable
has to be strung to each of the devices in the network. With the
exception in some cases of the first and last devices in a daisy
chain network, each device in the network requires a cable running
to it from a previous device and another cable running from it to
the next device.
[0006] Daisy chaining connections utilize termination resistors on
each end of the network to ensure that every transceiver is
directly connected to the main current path. Transceivers placed
outside the termination resistors daisy chain may not be able to
correctly sense the voltage drop and "hear" the transmission. In
this way "star" wiring configurations are not allowed for daisy
chained networks such as RS-485.
[0007] The disadvantage of wiring the network in this fashion is
that there must be some overall plan to the creation of the
network. The devices must be planned to some degree because a cable
running from the previous device must be connected to the device
and a different cable must be run to the next device. This requires
the person setting up the network to know where the previous device
is as well as the location of the next device. Knowing the
placements of the devices may not be overly complicated when the
network is small and centralized in one area, but often these daisy
chain networks have long distances between devices and these
devices might be in different locations that are not in sight of
each other. For example, in a HVAC system for a house, the devices
connected to the chain network will typically be a controller near
the furnace and a number of thermostats connected to the daisy
chain network and spread throughout the house. Each thermostat
device connected to the network will likely be situated in a
different room or location of the house from other devices and it
will not always be easy to determine in which direction to run the
cable to and from each device.
[0008] Additionally, some of the protocols such as RS-485 networks
require a termination resistor at the end of the network. This
requires one of the devices to serve as the last device and the
network must be planned to end at the device that has the
termination resistor in it.
[0009] Not only must the daisy chain network be planned to some
degree, but it can also be complicated to add new devices to the
network. To add a new device, the network must be disconnected from
one of the device and the new device incorporated into the chain.
Again, the location of the previous device and next device must be
known, which might not be that easy to determine if the network is
spread throughout a large building and numerous rooms.
[0010] The different standards for daisy chain networks also
specify the type of cable that is required in order to connect the
devices. RS-485, for example, specifies certain minimum standards
for cable and requires the cable to be a twisted pair in order to
use balanced differential signals to reduce or eliminate the effect
of interference in the cables.
[0011] There are many cables available that meet the
recommendations for the different daisy chain network protocols and
there are cables that are specially designed for use with these
applications. These cables are quite specialized and although daisy
chain networks are common, they are not as common as other more
standard types of networks. This often makes the special cabling
more costly and harder to find because of its lower production.
Also, electricians are often not familiar with these types of
specialty cables.
[0012] In more recent years a number of more standard cable
specifications have arisen that are not specifically made for daisy
chain networks. One very common type of standard cable is referred
to as Category 5 cabling. These standardized cables often include a
number of conductors or wire strands and standardized connections
to increase the ability of these standard cables to be used in a
number of different applications i.e. category 5 consists of four
twisted pairs of copper wire terminated by RJ45 connectors.
[0013] Because these standard cables can be used in so many
applications and circumstances and some, like Category 5 wire, are
in common use, they are manufactured in very large quantities which
generally makes them cheaper than other specialty cables, easier to
find and electricians and other installers are more often more
familiar with their use.
SUMMARY OF THE INVENTION
[0014] It is an object of the present invention to provide a system
and apparatus that overcomes problems in the prior art.
[0015] The present invention provides, in a first embodiment, a
master network device for creating a network in a daisy chain
configuration. The master network device comprises a network
component configured to operate on a daisy chain network and
comprising an output port and an input port for connection to the
daisy chain network; and a connector hub operative to connect a
plurality of network devices in a daisy chain network with cables,
wherein each cable comprises two conductors. The connector hub
comprises a plurality of sequential cable interfaces including a
first cable interface and a last cable interface, each cable
interface comprising a pair of conductor connectors, each conductor
connector operative to connect one conductor of a connected cable
to a connecting circuit. The connecting circuit is configured such
that one of the conductor connectors of the first cable interface
is connected to the output port of the network component and the
other of the conductor connectors of the first cable interface is
connected to one of the conductor connectors of a next cable
interface; the other of the conductor connectors of the next cable
interface is connected to one of the conductor connectors of a
succeeding cable interface, and conductor connectors of the
subsequent succeeding cable interfaces are connected sequentially
in the same manner; and the other of the conductor connectors of
the last cable interface is connected to the input port of the
network component.
[0016] The present invention provides, in a second embodiment,
connector hub to connect a plurality of network devices in a daisy
chain network with cables, wherein each cable comprises two
conductors. The connector hub comprises a connecting circuit; a
primary network device interface comprising a pair of conductor
connectors, each conductor connector operative to connect a
conductor to the connecting circuit; and a plurality of sequential
cable interfaces including a first cable interface and a last cable
interface, each cable interface comprising a pair of conductor
connectors, each conductor connector operative to connect one
conductor of a connected cable to the connecting circuit. The
connecting circuit is configured such that one of the conductor
connectors of the first cable interface is connected to one of the
conductor connectors of the primary network device interface and
the other of the conductor connectors of the first cable interface
is connected to one of the conductor connectors of a next cable
interface and the other of the conductor connectors of the next
cable interface is connected to one of the conductor connectors of
a succeeding cable interface; conductor connectors of the
subsequent succeeding cable interfaces are connected sequentially
in the same manner; and the other of the conductor connectors of
the last cable interface is connected to the other conductor
connector of the primary network device interface.
[0017] The system allows connection of each of a plurality of
network devices in a daisy chain configuration to a central
location in a network. Each network device is connected to a cable
with two conductors. From the central location, a signal is
transmitted down a first conductor in a cable to a network device
and the signal is then transmitted back from the network device
down a second conductor in the cable. From the central location,
the signal is then transmitted down the next cable to the next
network device. The cable connections can be made with a standard
plug and socket such as are readily available. In this manner,
networks that operate on a daisy chain can be wired from a central
location in a home run or free-form manner, yet maintain the daisy
chain configuration.
DESCRIPTION OF THE DRAWINGS
[0018] While the invention is claimed in the concluding portions
hereof, preferred embodiments are provided in the accompanying
detailed description which may be best understood in conjunction
with the accompanying diagrams where like parts in each of the
several diagrams are labeled with like numbers, and where:
[0019] FIG. 1 is a schematic diagram of a network in a daisy chain
configuration in accordance with the prior art;
[0020] FIG. 2 is a schematic illustration of an embodiment of a
master network device comprising a connector hub in accordance with
the present invention;
[0021] FIG. 3 illustrates a daisy chain configured network
implemented using a master network device in accordance with the
present invention;
[0022] FIG. 4 is a schematic illustration of a connector
device;
[0023] FIGS. 5a through 5g are schematic diagrams of connector
devices with alternate connecting circuits;
[0024] FIG. 6 illustrates a schematic of a connector hub in
accordance with the present invention;
[0025] FIG. 7 illustrates of schematic illustration of daisy chain
network implemented using a connector hub in accordance with the
present invention; and
[0026] FIG. 8 illustrates a socket and mating plug for connection
of a cable to a device in the network.
DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS
[0027] FIG. 1 is a schematic illustration of a network 1 in a daisy
chain configuration as known in the prior art. In network 1 a
number of network devices 121 are connected by a plurality of
network cables 5 that connect the network devices 121 in series.
Network devices 121 can be any devices that can operate on a daisy
chain configuration such as devices that use the RS485 standard.
The network cable 5 has a single conductor and in the case of a
daisy chain network operating using the RS485 standard, the single
conductor would be a twisted pair of copper wires.
[0028] In FIG. 1 each network device 121 is connected to two
network cables 5. The network is a chain where each network device
121 is connected to two network cables 5, one network cable 5
connecting the network device 121 to the previous network device
121 and another network cable 5 connecting the network device 121
to the next network device 121.
[0029] If the network 1 is configured in a master/slave
configuration that is fairly common in daisy chain configured
network, one of the network devices 121 will be the master device
on the network 1 and the rest of the network devices 121 will be
slave devices controlled by the master device.
[0030] The present invention uses network cable with at least two
conductors in a network that allows each network device to be
connected to the network by a single cable yet maintain the
configuration of a daisy chain network.
[0031] FIG. 2 is a schematic illustration of a master network
device 220. The master network device 220 comprises a network
component 230 and a connector hub 250. The network component 230
could be any known device that can be connected to a network in a
daisy chain configuration, i.e. a controller or other network
device and would comprises an output port 232 and an input port 235
for connection to a network configured in a daisy chain. While the
terms input and output are conveniently used in describing the
invention, it will be understood by someone skilled in the art that
if the network is configured to allow bi-directional communication,
a port or connection termed an input in this description may
transmit out a signal or a port or connection termed an output in
this description might receive a signal. Also, typically devices
configured to operate on a daisy chain configuration do not require
a specific input connection or output connection and the
connections can be interchanged without effecting the operation of
the network device.
[0032] Typically, if the daisy chain network is configured in a
master/slave configuration, the network component 230 would be
configured as the master device of the network.
[0033] Alternatively, the network component 230 could be a serial
to Ethernet (or other network standard) bridge. The network
component 230 would comprise an internet or other non-daisy chain
network connection 231 operative to connect the network component
to another network. Typically, this network connection would be a
conventional Ethernet or other network connection, but it could be
a wireless connection such as one that operates on the 802.11
standard for connection to a wireless network. This would allow a
daisy chain network created using the master network device 220 to
be in a remote location accessible over the internet or other
connection. Signal to be transmitted over a daisy chain network
created by the master network device 220 could be encapsulated and
sent over a network to the master network device 220 where the
network component 230 strips out the encapsulated signal and
transmits the signal onto the daisy chain network connected to the
master network device 220. In this manner, the master network
device 220 could serve as a bridge between a first daisy chain
network in a remote location and a daisy chain network connected to
the master network device 220.
[0034] The connector hub 250 allows the connection of the network
component 230 to a number of different network devices (not shown)
in a daisy chain configuration. Connector hub 250 comprises a first
cable interface 260, a second cable interface 270, a third cable
interface 280, a fourth cable interface 290 and a connection
circuit 255.
[0035] The first cable interface 260 is operative to connect to a
cable comprising at least two conductors and comprises a first
conductor connector 262 connectable to a first conductor of a cable
connected to the first cable interface 260 and a second conductor
connector 265 connectable to another conductor of a cable connected
to the first cable interface 260. Both the first conductor
connector 262 and the second conductor connector 265 of the first
cable interface 260 are connected to the connection circuit 255.
The second cable interface 270 is operative to connect to a cable
comprising at least two conductors and comprises a first conductor
connector 272 connectable to a first conductor of a cable connected
to the second cable interface 270 and a second conductor connector
275 connectable to another conductor of a cable connected to the
second cable interface 270. Both the first conductor connector 272
and the second conductor connector 275 of the second cable
interface 270 are connected to the connection circuit 255. The
third cable interface 280 is operative to connect to a cable
comprising at least two conductors and comprises a first conductor
connector 282 that is connectable to a first conductor of a cable
connected to the third cable interface 280 and a second conductor
connector 285 that is connectable to another conductor of a cable
connected to the third cable interface 280. Both the first
conductor connector 282 and the second conductor connector 285 of
the third cable interface 280 are connected to the connection
circuit 255. The fourth cable interface 290 is operative to connect
to a cable comprising at least two conductors and comprises a first
conductor connector 292 that is connectable to a first conductor of
a cable connected to the fourth cable interface 290 and a second
conductor connector 295 that is connectable to another conductor of
a cable connected to the fourth cable interface 290. Both the first
conductor connector 292 and the second conductor connector 295 of
the fourth cable interface 290 are connected to the connection
circuit 255.
[0036] The connection circuit 255 operatively connects the output
port 232 of the network component 230, the input port 235 of the
network component 230, the first cable interface 260, the second
cable interface 270, the third cable interface 280 and the fourth
cable interface 290 in a daisy chain configuration. The output port
232 of the network component 230 is operatively connected by the
connection circuit 255 to the first conductor connector 262 of the
first cable interface 260. The second conductor connector 265 of
the first cable interface 260 is operatively connected by the
connection circuit 255 to the first conductor connector 272 of the
second cable interface 270. The second conductor connector 275 of
the second cable interface 270 is operatively connected by the
connection circuit 255 to the first conductor connector 282 of the
third cable interface 280. The second conductor connector 285 of
the third cable interface 280 is operatively connected by the
connection circuit 255 to the first conductor connector 292 of the
fourth interface 290. The second conductor connector 295 of the
fourth cable interface 290 is operatively connected by the
connection circuit 255 to the input port 235 of the network
component 230.
[0037] It will be readily understood by someone skilled in the art
that the conductor could comprises a twisted wire pair and each
conductor connector would be a pair of connectors to connect to
each of the twisted wires in the pair.
[0038] In one embodiment of the invention, as illustrated in FIG.
8, the cable interfaces 260, 270, 280 and 290 would comprise a
socket 602 that is adapted to receive a plug 604 that is attached
to the end of the cable 115 that is connectable to the cable
interfaces 260, 270, 280 or 280. For example, it is contemplated
that the socket could be adapted to receive a plug conforming to
the RJ45 standard that is attached to the end of a cable conforming
to the category 5 standard for cable. When the plug is inserted
into the socket and the connection is made, the conductor
connectors will be connected with the proper conductors in the
cable.
[0039] Although FIG. 2 illustrates a connector hub 250 comprising
four cable interfaces for connecting to four cables, it is
contemplated that any practical number of additional interfaces
could be incorporated into the connector hub 250 by simply
extending the connecting circuit 255.
[0040] FIG. 3 illustrates a daisy chain configured network 300
implemented using the master network device 220 of FIG. 2. The
network 300 comprises: the master device 220; a number of network
device 320A, 320B, 320C, and 320D; and a plurality of cables 115A,
115B, 115C, 115D and 115E; a shorting plug 180 and a connector
device 110.
[0041] The master network device 220 comprises: first cable
interface 260; second cable interface 270; third cable interface
280; and fourth cable interface 290.
[0042] The network devices 320A, 320B, 320C and 320D are network
devices that require or allow connection to a daisy chain network,
such as devices that can operate using the RS-485 standard. These
devices could be any type of device that is useful to network in a
daisy chain configuration, i.e. a number of input devices or
control devices. If the network 300 is configured based on a
master/slave relationship between the devices, the master network
device 220 will be the controlling or master device and the network
devices 320A, 320B, 320C and 320D would be slave devices.
[0043] The cables 115A, 115B, 115C, 115D and 115E comprise a first
end and a second end and have at least two conductors. If the
cables 115A, 115B, 115C, 115D and 115E are designed for connected
network devices 320 that operate in accordance with the RS-485
standard, the two conductors will each be a twisted pair of copper
wires and if the cable 115A, 115B, 115C, 115D and 115E is category
5 cable, the cable will consists of four copper wire pairs. The
cables 115A, 115B, 115C, 115D and 115E could be terminated with any
typical ends that allow connection to the components of the network
200, including the stripped wire ends, however, the ends would
typically be RJ45 ends to allow quick snap connections to the
network devices 320 in the network 300.
[0044] The connector device 110 can be any connector that is
operative to maintain devices connected to it in a daisy chain
configuration. For example, connector device 110 can be the
connector device as shown in FIG. 4, which is a schematic
illustration of a connector device 10. The connector device 10
illustrated allows network devices (not shown) to be connected by
cables (not shown) to the connector device 10 in any fashion and
the connector device 10 will ensure that the network devices 120
connected to the connector device 10 by cables will be in a daisy
chain configuration. The connector device 10 comprises a first
cable interface 20, a second cable interface 22, a third cable
interface 24, and a connecting circuit 30.
[0045] The first cable interface 20, second cable interface 22 and
third cable interface 24 are configured to be connectable with a
cable comprising at least two conductors. The connector device
illustrated in FIG. 4 is configured for a daisy chain network
conforming to the RS-485 standard where each conductor is a twisted
pair of copper wires and therefore each cable interface is shown as
having four connections.
[0046] The connecting circuit 30 operably connects the conductors
of the cables connected to the cable interfaces in such a manner
that the daisy chain configuration of the network is maintained.
For the embodiment of the connector device as shown in FIG. 4, the
connecting circuit 30 operably connects the first wire pair of a
cable connected at conductor connectors 21A of the first cable
interface 20 of the connector device 10 to the first wire pair of
another cable connected to conductor connectors 23A of the second
cable interface 22 of the connector device 10. The second wire pair
of a cable connected to conductor connectors 21B of the first cable
interface 20 of the connector device 10 will be operably connected
by the connecting circuit 30 to the second wire pair of another
cable connected to the conductor connectors 25B of the third cable
interface 24. Finally, the connecting circuit 30 operably connects
the second wire pair of a cable connected to conductor connectors
23B of the second cable interface 22 to the first wire pair of a
cable connected to a conductor connector 25A of the third cable
interface 24.
[0047] Alternatively, connector device 110 could be a connector
device as illustrated in FIGS. 5a through 5g.
[0048] The shorting plug 180 in FIG. 3 connects a pair of conductor
connectors in an interface together when a cable is not connected
to the interface. Using the shorting plug 180 will maintain the
balance of the signal in the network, but is not strictly
required.
[0049] Referring again to FIG. 3, each of the network devices 320A,
320B, 320C and 320D are connected by an interface 330A, 330B, 330C
and 330D to one end of a cable 115A, 115B, 115C and 115D,
respectively. The other end of each cable 115A, 115B, 115C and 115D
is then connected to either a cable interface 270 or 280 on the
master network device 220 or a connector 110. Network device 320A
will be connected by a cable 115A to a connector 110. Another
network device 320B will also be connected by another cable 115B to
another interface on the connector 110. The connector 110 is
connected by a cable 115E to cable interface 260 of the master
network device 220. Network device 320C and network device 320D are
each connected by a cable 115C and cable 115D directly to cable
interfaces 270 and 280 of the master network device 220,
respectively. Cable interface 290 is not used in the illustrated
network 300 and has a shorting plug 180 inserted in it.
[0050] In operation network 300 operates as follows. Master network
device 220 transmits a signal. The signal is transmitted out
through conductor connector 262 of cable interface 260 and through
a first conductor in the cable 115E. The signal is transmitted into
connected device 110 and from connector device 110 through cable
115A and into network device 320A (if connector device 110 is the
connector device illustrated in FIG. 4). The signal is then
transmitted out of network device 320A through another conductor in
the cable 115A and back into connector device 110. From connector
device 110 the signal is transmitted through a first conductor in
cable 115B to the network device 320B. The signal then passes back
out of network device 320B through another conductor in cable 115B
back and into connector device 110 where the signal is then
transmitted back through another conductor in cable 115E and back
into the master network device 220 through conductor connector 265
of cable interface 260 to conductor connector 272 of cable
interface 270. The signal is then transmitted out of conductor
connector 272 of cable interface 270 through a first conductor in
the cable 115C and into network device 320C. From network device
320C the signal passes back though another conductor in cable 115C
and back through conductor connector 275 of cable interface 270 to
conductor connector 282 of cable interface 280. The signal is
transmitted out of conductor connector 282 of cable interface 280
through a first conductor of cable 115D to network device 320D.
From network device 320D, the signal is transmitted back through
another conductor of cable 115D and back through conductor
connector 285 of cable interface 280. The signal then passes
through conductor connector 292 of cable interface 290, through
shorting plug 190 to conductor connector 295, and then to input
port 235 of the network component 230 to complete the daisy
chain.
[0051] In another embodiment of the invention the connector hub is
separate from the first network device. FIG. 6 illustrates a
schematic of a connector hub 450 in accordance with the present
invention. Connector hub 450, like connector hub 250 in FIG. 2
comprises: a first cable interface 260; a second cable interface
270; a third cable interface 280; and a fourth cable interface 290.
Instead of being contained in the master network device with the
network component, the connector hub 450 is connectable to a
primary network device through a primary network device interface
240.
[0052] The primary network device interface 240 comprises an input
conductor connector 242 and an output conductor connector 245 and
the input conductor connector 242 and the output conductor
connector 245 are operative to connect to conductors (not shown)
from a primary network device (not shown). The primary network
device that is connected by conductors to the primary network
device interface 240 would typically be a master device if the
daisy chain network is configured in a master/slave relationship,
however it does not have to be. The conductors that connect the
primary network device to the primary network device 240 could each
comprises a single conductor and they could be wires (such as a
twisted pair) or a printed circuit board wherein the primary
network device interface 240 could connect to a slot on the primary
network device. Alternatively, these two conductors could be
enclosed in a single cable.
[0053] It will be readily understood by someone skilled in the art
that the conductors could comprise a twisted wire pair and each
conductor connector would be a pair of connectors to connect to
each of the twisted wires in the pair.
[0054] In one embodiment of the invention, as illustrated in FIG.
8, the cable interfaces 260, 270, 280 and 290 would comprise a
socket 602 that is adapted to receive a plug 604 that is attached
to the end of a cable 115 that is connectable to the cable
interface 260, 270, 280 or 290. For example, it is contemplated
that the socket could be adapted to receive a plug conforming to
the RJ45 standard that is attached to the end of a cable conforming
to the category 5 standard for cable. When the plug is inserted
into the socket and the connection is made, the conductor
connectors will be connected with the proper conductors in the
cable.
[0055] Although FIG. 6 illustrates a connector hub 450 comprising
four cable interfaces for connecting to four cables, it is
contemplated that any practical number of additional interfaces
could be incorporated into the connector hub 250 in the manner
shown.
[0056] FIG. 7 illustrates of schematic illustration of daisy chain
configured network 500 implemented using the connector hub 450.
Network 500 comprises: a primary network device 350; connector hub
450; a plurality of cables 115A, 115B, 115C, 115D, and 115E; a
plurality of network devices 320A, 320B, 320C and 320D; a shorting
plug 180 and a connector device 110. The network 500 operates in
the same manner as the network 300 of FIG. 3
[0057] The cables 115A, 115B, 115C, 115D and 115E comprise a first
end and a second end and have at least two conductors. If the
cables 115A, 115B, 115C, 115D and 115E are for connected network
devices 120 that operate in accordance with the RS-485 standard the
two conductors will each be a twisted pair of copper wires and if
the cable 115A, 115B, 115C, 115D and 115E is category 5 cable, the
cable will consists of four copper wire pairs. The cables 115A,
115B, 115C, 115D and 115E could be terminated with any typical ends
that allow connection to the components of the network 500,
including the stripped wire ends, however, the ends would typically
be RJ45 ends to allow quick snap connections to corresponding
sockets in the components in the network 500.
[0058] The foregoing is considered as illustrative only of the
principles of the invention. Further, since numerous changes and
modifications will readily occur to those skilled in the art, it is
not desired to limit the invention to the exact construction and
operation shown and described, and accordingly, all such suitable
changes or modifications in structure or operation which may be
resorted to are intended to fall within the scope of the claimed
invention.
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