초록 ▼

A swivel caster assembly has a molded plastic caster horn with an upwardly opening socket receiving a connector stem, the portion thereof above the caster horn having either a plate, a threaded post, or a smooth post with a retaining ring, for connection to an object to be supported by the caster. T

A swivel caster assembly has a molded plastic caster horn with an upwardly opening socket receiving a connector stem, the portion thereof above the caster horn having either a plate, a threaded post, or a smooth post with a retaining ring, for connection to an object to be supported by the caster. The caster horn and the received stem portions of the various connectors are the same, so the same horn can receive any type of connector. The horn is shaped to receive locking features for wheel, swivel, both wheel and swivel, or simply a snap-in cover where no locking feature is desired.

대표청구항 ▼

A swivel caster assembly has a molded plastic caster horn with an upwardly opening socket receiving a connector stem, the portion thereof above the caster horn having either a plate, a threaded post, or a smooth post with a retaining ring, for connection to an object to be supported by the caster. T

A swivel caster assembly has a molded plastic caster horn with an upwardly opening socket receiving a connector stem, the portion thereof above the caster horn having either a plate, a threaded post, or a smooth post with a retaining ring, for connection to an object to be supported by the caster. The caster horn and the received stem portions of the various connectors are the same, so the same horn can receive any type of connector. The horn is shaped to receive locking features for wheel, swivel, both wheel and swivel, or simply a snap-in cover where no locking feature is desired. et of goggles as defined in claim 10, wherein each projection includes an upstanding tab dimensioned for receipt of said rip off sheets.12. An improved set of goggles as defined in claim 11, wherein each tab is specifically dimensioned for receipt of up to approximately five rip off sheets.13. An improved set of goggles as defined in claim 8, wherein each projection includes an upstanding tab dimensioned for receipt of said rip off sheets.14. An improved set of goggles as defined in claim 13, wherein each tab is specifically dimensioned for receipt of up to approximately five rip off sheets. tion that said associated acquire value has a predetermined relationship with an associated semaphore value.4. A shared resource management system as recited in claim 3 wherein said predetermined relationship between said associated acquire value and said associated semaphore value is determined if said associated acquire value equals said associated semaphore value.5. A shared resource management system as recited in claim 1 wherein each of said synchronization commands is associated with one of said execution units, and wherein said synchronization commands comprise a release command having an associated release value indicating that said associated execution unit is to relinquish ownership of the shared resource after said associated execution unit is done accessing a shared resource.6. A shared resource management system as recited in claim 3 wherein said channel control unit is operative to perform a shared resource ownership acquisition process in response to a received acquire command having an associated received acquire value, said acquire process comprising the steps of:comparing the received acquire value with an associated current semaphore value to determine whether a predetermined relationship is satisfied between said received acquire value and said associated current semaphore value; andif said predetermined relationship is satisfied, providing a portion of the execution instructions associated with said received acquire command to said associated execution unit via said associated channel.7. A shared resource management system as recited in claim 6 wherein said acquire process further comprises the steps of:if said predetermined relationship is not satisfied, determining whether a predetermined timeout period has expired; andif said predetermined timeout period has expired, providing a portion of the execution instructions associated with said received acquire command to said associated execution unit via said associated channel.8. A shared resource management system as recited in claim 5 wherein said channel control unit is operative to perform a shared resource ownership release process in response to a received release command having an associated received release value, said release process comprising the steps of:determining whether the associated execution unit is done processing a portion of said associated execution instructions associated with a previously received acquire command; andif said execution unit is done, writing said associated release value to an associated semaphore storage location.9. A shared resource management system as recited in claim 2 wherein each of said first and second channels is a virtual DMA channel, wherein each of said synchronization commands is associated with one of the first and second virtual DMA channels, and wherein said channel control unit is operative to activate each of said first and second virtual DMA channels to provide at least one of the associated synchronization commands to the associated one of the first and second execution units upon initiation of an associated time slice period.10. A shared resource management system as recited in claim 9 wherein said channel control unit is operative to activate the virtual DMA channels one at a time in accordance with a round robin arbitration scheme.11. A shared resource management system as recited in claim 9 wherein said synchronization commands include an acquire command having an associated acquire value, and wherein said channel control unit is operative to perform a shared resource ownership acquisition process for each of the first and second virtual DMA channels in response receiving an acquire command having an associated acquire value via a particular virtual DMA channel that is currently activated, said acquire process comprising the steps of:comparing the received acquire value with an as sociated current semaphore value to determine whether a predetermined relationship is satisfied between said received acquire value and said associated current semaphore value;if said predetermined relationship is not satisfied, determining whether a predetermined timeout period has expired;if said predetermined timeout period has not expired, deactivating the particular virtual DMA channel, and activating a next virtual DMA channel.12. A shared resource management system as recited in claim 9 wherein said channel control unit is operative to perform the steps of:determining whether a particular virtual DMA channel has been activated for a period of time exceeding a predefined time slice period; andif said particular virtual DMA channel has been activated for a period of time exceeding said predefined time slice period, deactivating said particular virtual DMA channel.13. A process of coordinating accessing of a shared resource by a plurality of execution units, comprising the steps of: receiving a synchronization command having an associated value, the synchronization command being associated with a set of execution instructions for execution by an execution unit requiring access to a shared resource during execution of the set of execution instructions; andexecuting the set of execution instructions by the execution unit upon validation of the synchronization command based on a comparison of the value with a stored value stored at a storage location.14. A process of coordinating accessing of a shared resource by a plurality of execution units, comprising the steps of: receiving a first synchronization command having an associated first value, the first synchronization command being associated with a first set of execution instructions for execution by a first execution unit, the first execution unit requiring access to a shared resource during execution of the first set of execution instructions; andexecuting the first set of execution instructions by the first execution unit upon validation of the first synchronization command based on a comparison of the first value with a stored value stored at a storage location;receiving a second synchronization command having an associated second value; andwriting the second value to the storage location after the first execution unit is done processing the first set of execution instructions.15. A process of coordinating accessing of a shared resource as recited in claim 14 further comprising the steps of:receiving a third synchronization command having an associated third value, the third synchronization command being associated with a second set of execution instructions for execution by a second execution unit, the second execution unit requiring access to the shared resource during execution of the second set of execution instructions; andexecuting the second set of execution instructions by the second execution unit upon validation of the third synchronization command based on a comparison of the third value with the second value stored at the storage location.16. A process of coordinating accessing of a shared resource as recited in claim 14 wherein the step of receiving the first synchronization command comprises directly accessing a system storage that stores a list of instructions including a plurality of execution instructions and a plurality of synchronization commands interspersed between associated execution instructions.17. A process of coordinating accessing of a shared resource as recited in claim 16 wherein each of the synchronization commands is associated with one of the execution units, and wherein the synchronization commands comprise an acquire command having an associated acquire value, the acquire command indicating that the associated exe