An electrical switching device for controlling lighting or other electrical loads from multiple locations. Device toggle element indicates to a user whether or not the load is energized. A raised ON position indicates an energized load while lowered OFF position indicates the load is not energized. Toggle element position is changeable manually by the user or programmatically by an actuator mechanism. A mode of communication exists among devices so that when one device's toggle element position is changed manually, this change is communicated to other devices on the same circuit and these other devices activate their actuator in order to change the position of their toggle elements in synchronization. One or more loads are connected to devices and are energized when the respective device's toggle element is in the raised ON position and de-energized when the device's toggle element is in the lowered OFF position.

A knob for an input device includes a knob housing being rotatable on an axis, a shaft extending from the knob housing along the axis, a ratchet wheel axially coupled to the shaft with a toothed perimeter, and a ratchet arm to couple to the toothed perimeter of the ratchet wheel when the ratchet arm is engaged such that a ratcheted rotation occurs when the knob is rotated, and decouple from the toothed perimeter of the ratchet wheel when the ratchet arm is disengaged. The knob can further include a resistance wheel axially coupled to the shaft with a substantially smooth perimeter, and a resistance arm to couple to the smooth perimeter of the resistance wheel when the resistance arm is engaged such that a friction is provided when the knob is rotated, and decouple from the smooth perimeter of the resistance wheel when the resistance arm is disengaged.

A knob for an input device includes a knob housing being rotatable on an axis, a shaft extending from the knob housing along the axis, a ratchet wheel axially coupled to the shaft with a toothed perimeter, and a ratchet arm to couple to the toothed perimeter of the ratchet wheel when the ratchet arm is engaged such that a ratcheted rotation occurs when the knob is rotated, and decouple from the toothed perimeter of the ratchet wheel when the ratchet arm is disengaged. The knob can further include a resistance wheel axially coupled to the shaft with a substantially smooth perimeter, and a resistance arm to couple to the smooth perimeter of the resistance wheel when the resistance arm is engaged such that a friction is provided when the knob is rotated, and decouple from the smooth perimeter of the resistance wheel when the resistance arm is disengaged.

A knob for an input device may include a knob housing being rotatable on an axis, a shaft coupled to and extending from the knob housing along the axis, a ratchet wheel axially coupled to the shaft and including a toothed perimeter, and a resistance wheel axially coupled to the shaft and including a smooth perimeter, where the ratchet wheel and the resistance wheel are rotatable on the axis in correspondence with a rotation of the knob housing. A biasing mechanism provides a force on its first end to cause a roller to engage with the toothed perimeter of the ratchet wheel such that a ratcheted rotation occurs when the knob housing is rotated, and further provides a force on its second end to cause the second end to engage with the smooth perimeter of the resistance wheel such that a friction is provided when the knob housing is rotated.

A radiation therapy system includes an X-ray imaging system that is configured with a combined and simplified filter and collimator positioning mechanism. In addition, an X-ray imager of the RT system is only positioned at a few discrete locations within a plane that is a fixed distance from the imaging X-ray source when generating X-ray images. As a result, for each of these discrete imaging positions, the simplified filter and collimator positioning mechanism positions a specific collimator-filter combination in a specific location between the X-ray source and the imager.

A knob for an input device may include a knob housing being rotatable on an axis, a shaft coupled to and extending from the knob housing along the axis, a ratchet wheel axially coupled to the shaft and including a toothed perimeter, and a resistance wheel axially coupled to the shaft and including a smooth perimeter, where the ratchet wheel and the resistance wheel are rotatable on the axis in correspondence with a rotation of the knob housing. A biasing mechanism provides a force on its first end to cause a roller to engage with the toothed perimeter of the ratchet wheel such that a ratcheted rotation occurs when the knob housing is rotated, and further provides a force on its second end to cause the second end to engage with the smooth perimeter of the resistance wheel such that a friction is provided when the knob housing is rotated.

At each step of a workflow performed by an operator that involves a plurality of input mechanisms in a radiation therapy system, the operator is assisted in the process of selecting the next input mechanism in a way that greatly reduces the number of possible input mechanisms that can be chosen. A first subset of input mechanisms is made visually prominent via a first visual technique and a second subset of the input mechanisms is made visually prominent via a second visual technique. The first subset includes input mechanisms that are available for selection at that particular step in the workflow and the second subset includes recommended input mechanisms that are the most likely to be the next input mechanism that should be actuated by the operator at that particular step in the workflow.

A radiation therapy system includes an X-ray imaging system that is configured with a combined and simplified filter and collimator positioning mechanism. In addition, an X-ray imager of the RT system is only positioned at a few discrete locations within a plane that is a fixed distance from the imaging X-ray source when generating X-ray images. As a result, for each of these discrete imaging positions, the simplified filter and collimator positioning mechanism positions a specific collimator-filter combination in a specific location between the X-ray source and the imager.

A radiation therapy system includes a treatment couch positioning assembly that is directly coupled to a fixed structure supporting the linear accelerator of the radiation therapy system. The radiation therapy system can be installed in a radiation therapy facility without the floor of the facility being excavated and a sub-floor structure, such as a base frame, being installed. To laterally position a patient relative to the linear accelerator, the treatment couch positioning assembly of the radiation therapy system is laterally translated via a linear motor, and laterally translates with the treatment couch, rather than cantilevering the treatment couch to either side of the couch positioning assembly.

A motion-enable device includes a mechanical switch and a capacitive sensor with a sensing region that is located adjacent to the mechanical switch. The mechanical switch enables a first signal when closed or actuated that indicates that the mechanical switch is in an active state. The capacitive sensor enables a second signal when a conductive object is disposed in the sensing region, where the second signal indicates that the capacitive sensor is in an active state. Enablement of operation of an apparatus depends on receipt of both the first signal and the second signal. The mechanical switch and the capacitive sensor act as the two separate switches required by functional safety requirements for a motion enable device. Because the sensing region of the capacitive sensor is adjacent to the mechanical switch, the first and second signals are generated when an operator actuates the mechanical switch with a single digit.