Abstract: Linear actuators driven by everted ball screw assemblies are described herein. In some examples, the everted ball screw assembly includes a hollow screw shaft with internal threads, a ball cylinder concentrically positioned therein and having external threads, and a plurality of balls sized to fit in a substantially contiguous series along a working pathway that is defined by the space between the internal and external threads. One or more limiters prevent the ball cylinder from rotating. A motor rotates the hollow screw shaft, thereby driving the balls along the pathway and imparting linear motion to the ball cylinder, which is coupled to a connecting rod for actuating a load. The ball cylinder in some examples includes an internal return path with scoop elements that are sized and shaped to guide the balls into the internal return path and then back onto the working pathway.

Abstract: Linear actuators are described herein. In particular embodiments, a linear actuator includes an everted ball screw assembly comprising a hollow screw shaft with internal threads, a ball cylinder concentrically positioned therein and having external threads, and a plurality of bearing balls sized to fit in a substantially contiguous series along a working pathway defined by the space between the internal and external threads. The linear actuator may include a support bearing for rotatably supporting the screw shaft in a housing. The ball cylinder in particular embodiments includes an internal return path along which the balls return to the working pathway. The everted ball screw assembly may include a lash reduction assembly and one or more scoop inserts that are sized and shaped to guide the balls into the internal return path and back onto the working pathway.

Abstract: Linear actuators driven by everted ball screw assemblies are described herein. In some examples, the everted ball screw assembly includes a hollow screw shaft with internal threads, a ball cylinder concentrically positioned therein and having external threads, and a plurality of balls sized to fit in a substantially contiguous series along a working pathway that is defined by the space between the internal and external threads. One or more limiters prevent the ball cylinder from rotating. A motor rotates the hollow screw shaft, thereby driving the balls along the pathway and imparting linear motion to the ball cylinder, which is coupled to a connecting rod for actuating a load. The ball cylinder in some examples includes an internal return path with scoop elements that are sized and shaped to guide the balls into the internal return path and then back onto the working pathway.

Abstract: Linear actuators are described herein, In particular embodiments, a linear actuator includes an everted ball screw assembly comprising a hollow screw shaft with internal threads, a ball cylinder concentrically positioned therein and having external threads, and a plurality of bearing balls sized to fit in a substantially contiguous series along a working pathway defined by the space between the internal and external threads. The linear actuator may include a support bearing for rotatably supporting the screw shaft in a housing. The ball cylinder in particular embodiments includes an internal return path along which the balls return to the working pathway. The everted ball screw assembly may include a lash reduction assembly and one or more scoop inserts that are sized and shaped to guide the balls into the internal return path and back onto the working pathway.

Abstract: A system and method for measuring flow resistance of a fluid in a conduit is provided. The system generally includes a reservoir for containing the fluid, a pump connected to the reservoir for distributing the fluid through a conduit having a straight measurement section, one or more pressure sensors connected to the conduit for measuring the pressure of the fluid in the conduit at one end of the straight measurement section and an opposite end of the straight measurement section.

Abstract: A scheme for message folder synchronization. In one embodiment, a method may comprise: automatically detecting arrival of a message at a messaging server for a user; storing the message in a first folder of a first folder system associated with the user at the messaging server; processing at least a portion of an instance of the message for transmission to the user's mobile data communication device over a wireless network; receiving a status signal from the mobile data communication device indicating that the message has been moved from a first folder at the mobile data communication device to a second folder of a second folder system associated with the user at the mobile data communication device; and responsive to the status signal, moving the message from the first folder of the first folder system at the messaging server to a second folder thereat corresponding to the second folder of the second folder system.

Abstract: A message status synchronization scheme. In one embodiment, a method may comprise: automatically detecting arrival of a message at a messaging server from a sender for a user having a mail address thereat, the message being displayable on a computer for the user with a status indicator icon associated therewith; processing at least a portion of an instance of the message for transmission to the user's mobile data communication device over a wireless network; upon receiving a reply message from the mobile data communication, configuring address information associated with the reply message and transmitting the reply message to the sending entity with the user's mail address as its originating address; receiving a status signal from the mobile data communication device indicating that the message has been replied to on the mobile data communication device; and altering the status indicator icon associated with the message on the computer responsive to the status signal.

Abstract: A scheme for message status indication. One embodiment of a method comprises one or more of the following: automatically detecting arrival of a message at a messaging server for a user having a mail address thereat, the message being displayable on a computer for the user with a status indicator icon associated therewith, wherein the message is received from a sending party that has requested a read receipt indication; processing at least a portion of an instance of the message for transmission to the user's mobile data communication device over a wireless network; receiving a status signal from the mobile data communication device indicating that the message has been read at the mobile data communication device; altering the status indicator icon associated with the message on the computer responsive to the status signal; and forwarding a read receipt indication to the sending party.

Abstract: A message status synchronization scheme. In one embodiment, a method may comprise: automatically detecting arrival of a message at a messaging server for a user having a mail address thereat, the message being displayable on a computer for the user with a status indicator icon associated therewith; processing at least a portion of an instance of the message for transmission to the user's mobile data communication device over a wireless network; receiving a status signal from the mobile data communication device indicating that the message has been deleted on the mobile data communication device; and altering the status indicator icon associated with the message on the computer responsive to the status signal.

Abstract: A scheme for message status indicator synchronization operable with a mobile data communication device. An embodiment comprises one or more of the following: upon receiving a message over a wireless network for a user, determining that the message is a redirected message facilitated by a redirector component associated with a messaging server for the user having a mail address thereat, wherein the determining is based on verifying a redirection flag associated with the message; presenting at least a portion of the message to the user; generating a status signal responsive to a change in the message's status upon the presenting; and transmitting the status signal to the redirector component.

Abstract: A scheme for message status indicator synchronization. An embodiment comprises one or more of the following: automatically detecting arrival of a message at a messaging server for a user having a mail address thereat, the message being displayable on a computer for the user with a status indicator icon associated therewith; processing at least a portion of an instance of the message for transmission to the user's mobile data communication device over a wireless network; receiving a status signal from the mobile data communication device; and altering the status indicator icon associated with the message on the computer responsive to the status signal.

Abstract: A unified messaging system, method and user interface is provided for a handheld mobile communication device. The method may include the following steps: (a) receiving a notification signal at the wireless device via the wireless data channel indicating that the unified messaging system received and stored a voice mail message intended for a user of the wireless device; (b) transmitting a command signal from the wireless device to the unified messaging system via the wireless data channel, the command signal including a message retrieval command; (c) receiving via the wireless voice channel a voice call initiated by a voice mail system component of the unified messaging system in response to the message retrieval command transmitted from the wireless device; and (d) receiving the voice mail message from the unified messaging system via the wireless voice channel.

Abstract: At a wireless communication device having memory storing multiple sets of electronic mail (email) messages, each of the sets of email messages having been received via a distinct email service account, multiple selectable icons are displayed. Each icon is for invoking a computer program for presenting a distinct one of the sets of email messages at the wireless communication device upon its selection. Each icon may include or be limited to a textual component which may identify the relevant email service and may indicate a number of unread messages. The icon may be automatically downloaded to the device from a remote location based on a specified network address, such as a uniform resource locator (URL).

Abstract: A system and method for reducing congestion in wireless communication systems is provided. An unsolicited message reduction system includes a message detector and an all points bulletin (APB) generator. The message detector applies predefined filtering rules to identify and act upon unsolicited email messages to reduce the total number of transmissions in the wireless communication system. The filtering rules include global and user rules, with the global rules normally having precedence over user rules. The APB generator allows messages to be sent wireless mobile communication devices through direct wireless messages instead of through email messages.

Abstract: A system and method of pushing user-selected data items from a host system to a user's mobile data communication device upon detecting the occurrence of one or more user-defined event triggers is provided. The user may then move (or file) the data items to a particular folder within a folder hierarchy stored in the mobile data communication device, or may execute some other system operation on the data item. Software operating at the mobile device and the host system then synchronizes the folder hierarchy of the mobile device with a folder hierarchy of the host system, and any actions executed on the data items at the mobile device are then automatically replicated on the same data items stored at the host system, thus eliminating the need for the user to manually replicate actions at the host system that have been executed at the mobile data communication device.