Patent Description:
Automation controllers arc special purpose computers used for controlling industrial automation and the like. Under the direction of stored programs, a processor of the automation controller examines a series of inputs (e.g., electrical input signals to the automation controller) reflecting the status of a controlled process and changes outputs (e.g., electrical output signals from the automation controller) based on analysis and logic for affecting control of the controlled process. The stored control programs may be continuously executed in a series of execution cycles, executed periodically, or executed based on events. The inputs received by the automation controller from the controlled process and the outputs transmitted by the automation controller to the controlled process arc normally passed through one or more I/O devices, which are components of an automation control system that serve as an electrical interface between the automation controller and the controlled process.

Traditional I/O devices typically include a base configured to couple the I/O device with a bus bar, communication bus, or the like, a terminal block for communicatively coupling the I/O device with field devices, and an I/O module that includes circuitry for performing communication functions and/or logic operations. In traditional automation control systems, the I/O module may be coupled to the base by pushing the module toward the base. Friction or a simple locking mechanism between parts of the I/O module and the base may help prevent the I/O module from disengaging from the base. In the past, locking toggle mechanisms have been employed to secure an I/O module to a base. In other arrangements, screws or other fasteners are used to secure an I/O module to a base. The I/O module may be removed from the base by pulling the I/O module away from the base. <CIT> relates to a retention mechanism assembly for processor cartridges with captured screw fasteners. An electronic cartridge, which has an integrated circuit package mounted to a substrate. The substrate is captured by a cover. The cover also captures a fastener. The cartridge has a pair of fasteners that are captured by the cover plates. Each fastener has a threaded portion which extends from a collar and head portion. The assembly further includes a retention mechanism, which is mounted to the motherboard by a number of fasteners. The retention mechanism is located adjacent to the connector. The mechanism has a pair of threaded apertures that can receive the threaded portions of the fastener. <CIT> relates to a panel member locking device. The panel member locking device comprises a bracket affixed to a frame shell, a driving rod, a guide tube for guiding the driving rod to move axially up and down relative to the bracket, a constraint member coupled between the driving rod and the bracket for guiding the driving rod to rotate relative to the bracket, a spring member sleeved onto the guide tube and stopped between ahead block of the guide tube and a shoulder inside the bracket, and a locking rod connected to the bottom end of the driving rod and movable and rotatable by the driving rod between a locking position and an unlocking position for detachably locking two stacked panel members at the frame shell. The flat swivel grip is rotated through about <NUM>° to move the horizontal stop block of the constraint member horizontally along the horizontal retaining slot portion of the L-shaped limiter slot of the bracket to force the protruding blocks of the bottom locking end piece of the locking rod into engagement with the second panel member at the bottom side of the oblong locating hole, thereby locking the frame shell, the first panel member and the second panel member together. <CIT> relates to a common structure and door for multiple door electrical enclosure latching systems. Each door is provided with latches that interface with the multi-latch compatible system to hold the doors closed. The door is provided with pin-type latches. Other doors are provided with plate-type latches. When a plate-type latch is employed, the rail does not come into play. Rather, the tongue of the latch plate is rotated behind the plate of the rail structure and abuts the rear plate to hold the assembly tightly in engagement. Again, a flange of door then abuts the front surface of plate, where a gasket may be provided, where desired.

It is the object of the present invention to improve coupling and uncoupling a module to a base with improved electrical connection and with improved visibility of the coupling status.

It is now recognized that it is desirable to provide more efficient and effective techniques for coupling, locking, and uncoupling I/O modules from bases of I/O devices. In accordance with one aspect of the present disclosure, an I/O system comprises an I/O base having a first connector component, an I/O module selectively attachable to the I/O base and having a second connector component adapted to mate with the first connector component, and a locking actuator assembly for securing the I/O module to the I/O base. The locking actuator assembly includes an actuator supported for axial and rotational movement by the I/O module, the actuator movable from an unlocked position having a first end of the actuator extending from a housing of the I/O module to a locked position wherein a second end of the actuator extends from the housing, the second end of the actuator including at least one flange adapted to pass through a corresponding slot/opening in a surface of the I/O base such that when the actuator is rotated the at least one flange restricts withdrawal of the actuator from the slot/opening in the I/O base.

The second connector component can be supported by a circuit board within the housing, and the actuator can be supported by a bracket secured to the circuit board adjacent the second connector component. The bracket can include a support having first and second ends secured to the circuit board at outboard locations of the circuit board such that a major portion of a width of the circuit board is bridged by the support. The support can include a cylindrical portion between its first and second ends through which the actuator extends. The assembly can further include a cap secured to the support, the cylindrical portion of the support and the cap defining a cavity in which at least one radially extending guide flange of the actuator is received. The cap and the cylindrical portion can define at least one slot in which the at least one guide flange is received, the at least one slot delimiting axial and rotational movement of the actuator. The at least one slot can be L-shape, having a first portion of the L-shape extending axially and a second portion of the L-shape extending circumferentially. A biasing element can be interposed between the at least one guide flange and the cylindrical portion of the support, the biasing element urging the actuator axially towards to unlocked position. The first end of the actuator can extend from a first exterior side of the housing of the I/O device when in the unlocked position, and wherein the second end of the actuator extends from a second exterior side of the housing opposite the first exterior side when in the locked position. The support can be secured to the circuit board adjacent the second exterior side of the housing.

In accordance with another aspect, a locking actuator assembly for selectively securing together associated first and second devices of an associated I/O system comprises a locking actuator assembly including an actuator supported for axial and rotational movement by a circuit board of the associated first device, the actuator movable from an unlocked position to a locked position upon axial depression and rotation of a first end of the actuator, wherein a second end of the actuator includes at least one flange adapted to pass through a corresponding slot/opening in a surface of the associated second device such that when the actuator is rotated the at least one flange restricts withdrawal of the actuator from the slot/opening in the surface of the associated second device.

The circuit board can support a first connector component adapted to mate with a second connector component of the associated second device, and the actuator can be supported by a bracket secured to the circuit board adjacent the connector component. The actuator can be supported by the support at a location between first and second ends of the support, the first and second ends of the support being secured to the circuit board at outboard locations thereof such that a major portion of a width of the circuit board is bridged by the support. A cylindrical portion of the bracket and a cap secured to the bracket define a cavity in which a radially extending guide flange of the actuator is received. The cap and the cylindrical portion define at least one slot in which the at least one radially extending guide flange is received, the at least one slot delimiting axial and rotational movement of the actuator. The at least one slot can be L-shape having a first portion of the L-shape extending axially and a second portion of the L-shape extending circumferentially. A biasing element can be interposed between the at least one guide flange and the cylindrical portion of the support, the biasing element urging the actuator axially towards to unlocked position. The bracket can be secured to the circuit board adjacent an edge thereof, and the actuator can be coextensive with the circuit board in a direction perpendicular to the bracket.

In accordance with another aspect, a method of securing a first device of an I/O system to a second device of an I/O system comprises coupling the first device to the second device, and locking the first device to the second device with a locking actuator assembly. The locking actuator assembly includes an actuator supported for axial and rotational movement by a circuit board of the first device, the actuator movable from an unlocked position to a locked position upon axial depression and rotation of a first end of the actuator, wherein a second end of the actuator includes at least one flange adapted to pass through a corresponding slot in a surface of the second device such that when the actuator is rotated the at least one flange restricts withdrawal of the actuator from the slot/opening in the surface of the second device. Locking the first device to the second device can include depressing and rotating the first end of the actuator from an external side of the first device opposite the second device.

<FIG> is a diagrammatical representation of a control and monitoring system adapted to interface with networked components and configuration equipment in accordance with embodiments of the present techniques. A full description of the system is set forth in commonly-assigned <CIT>, which is hereby incorporated herein by reference in its entirety.

The control and monitoring system is generally indicated by reference numeral <NUM>. Specifically, the control and monitoring system <NUM> is illustrated as including a human machine interface (HMI) <NUM> and an automation controller or control/monitoring device <NUM> adapted to interface with components of a process <NUM>.

The illustrated process <NUM> includes sensors <NUM> and actuators <NUM>. The sensors <NUM> can include any number of devices adapted to provide information regarding process conditions. The actuators <NUM> can include any number of devices adapted to perform a mechanical action in response to a signal from a controller (e.g., an automation controller). The sensors <NUM> and actuators <NUM> can be utilized to operate process equipment. Indeed, they can be utilized within process loops that are monitored and controlled by the control/monitoring device <NUM> and/or the HMI <NUM>. Such a process loop can be activated based on process inputs (e.g., input from a sensor <NUM>) or direct operator input received through the HMI <NUM>.

As illustrated, the sensors <NUM> and actuators <NUM> are in communication with the control/monitoring device <NUM> and may be assigned a particular address in the control/monitoring device <NUM> that is accessible by the HMI <NUM>. As illustrated, the sensors <NUM> and actuators <NUM> can communicate with the control/monitoring device <NUM> via one or more I/O devices <NUM> coupled to the control/monitoring device <NUM>. The I/O devices <NUM> can transfer input and output signals between the control/monitoring device <NUM> and the controlled process <NUM>. The I/O devices <NUM> can be integrated with the control/monitoring device <NUM>, or can be added or removed via expansion slots, bays or other suitable mechanisms. For example, additional I/O devices <NUM> can be added to add functionality to the control/monitoring device <NUM>.

The I/O devices <NUM> can include input modules that receive signals from input devices such as photo-sensors and proximity switches, output modules that use output signals to energize relays or to start motors, and bidirectional I/O modules, such as motion control modules which can direct motion devices and receive position or speed feedback. In some arrangements, the I/O devices <NUM> can convert between AC and DC analog signals used by devices on a controlled machine or process and DC logic signals used by the control/monitoring device <NUM>.

<FIG> is a perspective view of a plurality of I/O devices <NUM> connected to an I/O adapter <NUM> in accordance with embodiments of the present techniques. The I/O adapter <NUM> is configured to provide system power to the I/O modules <NUM>, as well as to enable conversion between the communications protocols of the I/O devices <NUM> and the control/monitoring device <NUM>. As illustrated, the I/O adapter <NUM> and the plurality of I/O devices <NUM> are mounted to a DIN rail <NUM>, which is an industry standard support rail for mounting control equipment in racks and cabinets. The plurality of I/O devices <NUM> are electrically coupled in series along the DIN rail <NUM> such that field power and system information and power may be communicated between the I/O devices <NUM>, and back through the I/O adapter <NUM> to the control/monitoring device <NUM>.

Each of the I/O devices <NUM> includes a base <NUM> for physically and communicatively connecting the I/O device <NUM> to the DIN rail <NUM>, the I/O adapter <NUM> and/or adjacent I/O devices <NUM>, a terminal block <NUM>, and one or more I/O modules <NUM>. The terminal block <NUM> may be used to electrically connect the I/O device <NUM> to field devices, such as the sensors <NUM> and actuators <NUM> illustrated in <FIG>. In certain arrangements, the terminal block <NUM> can be removable from the base <NUM>. The I/O modules <NUM> may include I/O control circuitry and/or logic. In general, the I/O modules <NUM> receive input signals from the field devices, deliver output signals to the field devices, perform general and/or specific local functionality on the inputs and/or outputs, communicate the inputs and/or outputs to the control/monitoring device <NUM> and/or the other I/O devices <NUM>, and so forth.

With reference to <FIG> and <FIG>, an exemplary I/O system is illustrated and identified generally by reference numeral <NUM>'. It should be appreciated that the I/O system <NUM>' generally includes many of the same components, features and functionality of the I/O system <NUM> shown and described in connection with <FIG> and <FIG>. These components include, generally, an I/O base <NUM>' mountable to a DIN rail (not shown) and having a base circuit board <NUM> with a plurality of connectors C1, a plurality of I/O devices <NUM>' each including an I/O module <NUM>' mounted to the base <NUM>' and a terminal block <NUM>'. Each I/O module <NUM>' includes a connector C2 adapted for mating with a respective connector C1 of the I/O base <NUM>'.

In accordance with the present disclosure, each I/O module <NUM>' includes a locking actuator assembly <NUM> for securing the I/O module <NUM>' to the base <NUM>'. With additional reference to <FIG>, the locking actuator assembly <NUM> generally includes a spring-loaded actuator <NUM> supported for rotational and reciprocating movement within a housing <NUM> of the I/O module <NUM>' by a collar C and a bracket <NUM>. Collar C in the illustrated embodiment is supported in an LED circuit board <NUM> of the I/O module <NUM>'. Bracket <NUM> is secured to a main circuit board <NUM> of the I/O module <NUM>' adjacent connector component C2 of the I/O module <NUM>'. The actuator <NUM> is movable from a first, unlocked position, shown in <FIG> to a second, locked position shown in <FIG>.

A first end <NUM> of the actuator <NUM> includes a slot <NUM> for engagement with a tool, such as a screwdriver, for depressing and rotating the actuator <NUM>. It will be appreciated that other arrangements for facilitating depression and rotation of the actuator <NUM> can be employed without departing from the scope of the present disclosure, such as hex or torx arrangements, knobs etc. An opposite end <NUM> of the actuator <NUM> includes radially outwardly extending flanges F giving the actuator <NUM> a T-shape cross-section. The end <NUM> of the actuator <NUM> protrudes beyond the housing <NUM> when the actuator <NUM> is in the locked position, as best seen in <FIG>.

Turning to <FIG>, the locking actuator assembly <NUM> is shown isolated from the housing <NUM> of the I/O module <NUM>'. The collar C is received in a slot in the LED circuit board <NUM> and supports the actuator <NUM> for rotational and reciprocating movement at a location adjacent the first end <NUM> of the actuator <NUM>. The bracket <NUM> includes a longitudinally extending support <NUM> secured to the main circuit board <NUM> with fasteners <NUM>, such as pins, screws, adhesive etc., at outboard locations of the main circuit board <NUM> immediately adjacent a lower terminal edge of the circuit board <NUM>. In the illustrated embodiment, the bracket <NUM> is not attached to the circuit board <NUM> between the fasteners <NUM> thereby maintaining a major portion of the circuit board <NUM> available for surface mount components and the like. The bracket <NUM> spans a majot portion of the circuit board <NUM> between the fasteners <NUM>.

With additional reference to <FIG>. the bracket <NUM> includes a barrel portion <NUM> through which the second end <NUM> of the actuator <NUM> extends. The barrel portion <NUM> includes opposite axially extending arms A that extend from the support <NUM> and a cylindrical portion <NUM> extending from the arms A.

As best seen in <FIG>, the actuator <NUM> includes radially extending flanges <NUM>. The radially extending flanges <NUM> extend in opposite radial directions and are received in respective L-shape slots <NUM> formed by portions of the arms A, the cylindrical portion <NUM> and a cap <NUM> that is secured to the bracket support <NUM>. The L-shape slots <NUM> have an axially extending portion AE and a circumferentially extending portion CE. In the illustrated embodiment, the axially extending portion corresponds to the base horizontal portion of the L-shape while the circumferentially extending portion corresponds to the vertical portion of the L-shape.

Flanges <NUM> of the actuator <NUM> are captured between the barrel portion <NUM> of the bracket <NUM> and the cap <NUM>, and a biasing element in the form of a coil spring S (see <FIG>) biases the actuator <NUM> upwardly towards the unlocked position. The spring S is received in the cylindrical portion <NUM> of the barrel portion <NUM> and urges the flanges <NUM> of the actuator <NUM> upwardly.

It should be appreciated that the flanges <NUM>, being received in the L-shape slots <NUM> of the bracket <NUM>, restrict both reciprocating and rotational movement of the actuator <NUM>. In <FIG>, the actuator <NUM> is shown depressed against the biasing force of the spring S. Further depression of the actuator <NUM> is restricted by the flanges <NUM> impinging on a circumferential end wall of the cylindrical portion <NUM> of the barrel portion <NUM>. Counterclockwise rotation of the actuator <NUM> is also restricted by the flanges <NUM> impinging on the arms A. From the position illustrated in <FIG>, the actuator <NUM> is free to travel upwardly in <FIG> to an undepressed position, corresponding to an unlocked position, limited by impingement of the flanges <NUM> on a circumferential end face of the cap <NUM>, and free to rotate clockwise to the left in <FIG> to a locked position. When rotated to the locked position, the flanges <NUM> are wrapped in the circumferentially extending portion CE of the slots <NUM> and thereby the actuator <NUM> is restricted from axial movement.

It will now be appreciated that the I/O module <NUM>' can be secured to the base <NUM>' after engagement of the connector component C2 of the I/O module <NUM>' with the connector component C1 of the base <NUM>' by depressing end <NUM> of the actuator and then rotating the actuator clockwise <NUM> degrees.

Returning to <FIG>, when the actuator <NUM> is in the unlocked position, the flanges F of the end <NUM> of the actuator are aligned with a correspondingly-shaped opening O in the circuit board <NUM> of the base <NUM>'. When the actuator <NUM> is depressed, the flanges F of the end <NUM> of the actuator <NUM> pass through the opening O to a position below the circuit board <NUM>. Rotation of the actuator <NUM> ninety degrees results in the flanges F no longer being aligned with the opening O in the circuit board <NUM>. Accordingly, as the spring urges the actuator <NUM> upwardly, the flanges F engage an opposite side of the circuit board <NUM> surrounding the opening O. Thus, the spring force of the spring S holds the I/O module <NUM>' and, more directly, the circuit board <NUM> of the I/O module <NUM>', against the circuit board <NUM> base <NUM>'.

It should be appreciated that springs having various spring constants can be employed to apply a wide range of holding forces. In some embodiments, the spring S can be omitted. In many applications, however, the spring-loaded actuator is desirable for accommodating tolerance stack-up in the various components of the I/O system and/or the locking actuator assembly <NUM>.

It should also be appreciated that the locking actuator assembly <NUM> of the present disclosure locates the interlocking features (e.g., flanges F and opening O) in close proximity to the connector components C1 and C2 of the I/O module <NUM>' and base <NUM>'. This results in a more compact force path between the interlocked components. For example, the actuator <NUM> engages the circuit board <NUM> of the base <NUM>' in close proximity to the attachment points/fasteners <NUM> of the support <NUM> to the main circuit board <NUM>. As such, a major portion of the actuator <NUM> is not under load in the locked position, the forces instead being transferred from the flanges F to the flanges <NUM> through spring S to barrel portion <NUM> and to the main circuit board <NUM> via the support <NUM>. However, the actuator <NUM> remains conveniently accessible from an outer surface of the I/O module <NUM>', and also provides a visual indication of the status (e.g., locked or unlocked) of the locking actuator assembly (e.g., the actuator end <NUM> is proud of the housing <NUM> when unlocked, and flush with the housing <NUM> when locked). Interlocking the circuit boards <NUM> and <NUM> in close proximity to the connector pair achieves a more reliable connection between the connector pairs, and eliminates any tolerance stack-up that would result from interlocking, for example, the housings of an I/O module and I/O base.

As shown best in <FIG>, the L-shape slots <NUM> limit the travel of the actuator <NUM> axially and rotationally. As such, actuator point of failure can be designed into the actuator <NUM> for situations where excessive force is applied to the actuator <NUM>. Such points of failure include, but are not limited to, the screwdriver slot <NUM>, the flanges <NUM>, and/or the shaft of the actuator <NUM>.

Turning to <FIG>, another exemplary embodiment of an I/O in accordance with the present disclosure is illustrated and identified generally by reference numeral <NUM>". In this embodiment, two locking actuator assemblies <NUM>" are provided at opposite corners of the I/O module <NUM>". The locking actuator assemblies <NUM>" are similar to the locking actuator assembly <NUM> of <FIG>, with the exception that the support <NUM> is omitted in the locking actuators <NUM>". Instead, the locking actuator assemblies <NUM>" are mounted directly to the main circuit board <NUM>" via bracket B".

<FIG> illustrates another exemplary embodiment of an I/O module <NUM>‴ in accordance with the present disclosure. In this example, a locking actuator assembly <NUM>‴ is fixed directly to a main circuit board <NUM>‴ via bracket B‴.

It should be appreciated that the form and function of the locking actuator assemblies <NUM>" and <NUM>‴ are the same as locking actuator assembly <NUM> described in detail above except for the structure attaching them to the circuit boards.

Claim 1:
An I/O system comprising:
an I/O base (<NUM>') having a first connector component;
an I/O module (<NUM>') selectively attachable to the I/O base and having a second connector component adapted to mate with the first connector component; and
a locking actuator assembly (<NUM>) for securing the I/O module to the I/O base;
wherein the locking actuator assembly includes an actuator (<NUM>) supported for axial and rotational movement by the I/O module, the actuator movable from an unlocked position having a first end (<NUM>) of the actuator extending from a housing (<NUM>) of the I/O module to a locked position wherein a second end (<NUM>) of the actuator extends from the housing, the second end of the actuator including at least one flange (F) adapted to engage a corresponding surface of the I/O base when the actuator is rotated such that the at least one flange restricts withdrawal separations of the I/O module from the I/O base, wherein the I/O module includes a circuit board supporting the second connector component, wherein the actuator is supported by a bracket (<NUM>) secured to the circuit board of the I/O module adjacent the second connector component.