MXPA06010211A - Video processor alignment clamping spring - Google Patents

Abstract

A clamping spring (70) formed of a sheet of resilient material having an interconnected plurality of alternating first and second tabs disposed around the periphery thereof is disclosed. The first tabs (72) being angled upwardly and having mounting slots (73) therein. The second tabs (74) being angled downwardly. A force applied to the first tabs provides a consistent controlled clamping force at the second tabs.

Description

CLOSING SPRING FOR VIDEO PROCESSOR ALIGNMENT CROSS REFERENCE WITH RELATED APPLICATIONS This application claims the benefit of Provisional Patent Application Serial No. 60 / 554,743, and entitled "VIDEO PROCESSOR ALIGNMENT CLAMPING SPRING", filed on March 19, 2004, which is hereby incorporated in its entirety as reference.

FIELD OF THE INVENTION The invention relates generally to a digital light processing projection (DLP ™) system for use in a micro-deployment.

BACKGROUND OF THE INVENTION At the core of each digital light processing projection (DLP ™) system is an optical semiconductor known as a digital micromirror device (DMD) microcircuit. The mechanical alignment of the DMD microcircuit to rest on the light engine is critical to properly locate the image on the screen. A special attachment or machine is required to align the DMD assembly (including a heat sink and the PC board) with the array of core optics. The features are typically adapted within the assembly for the machine to manipulate the DMD microcircuit to align it. The existing light engine designs are mounted in the DMD assembly with the optical housing and then the optical system is adjusted around the position of the microcircuit. Because this alignment is carried out visually on the screen by the operator, the electronics are active during this alignment and the DMD microcircuit needs to be focused so that the proper alignment is carried out.

BRIEF DESCRIPTION OF THE INVENTION The present invention provides a fastening spring, including a sheet of elastic material having an interconnected plurality of first and second alternating tabs disposed around the periphery thereof. The first tabs are angled upwards and have mounting slots therein. The second tabs are angled downwards. A force applied to the first tabs provides a controlled clamping force in the second tabs. In another embodiment, the present invention provides a fastening arrangement, wherein the DMD assembly is held together by a plurality of first shoulder bolts with springs wound thereon and the DMD assembly is secured to an optical housing by a spring and a plurality of second shoulder bolts extended through the longitudinal openings in the first shoulder bolts.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will now be described with reference to the accompanying drawings, in which: Figure 1 shows an exploded view of a DMD clamping assembly for the alignment of a video processor in accordance with an exemplary embodiment of the present invention; and Figure 2 is an exploded view of a fastening assembly of Figure 1, taken generally along the axis 2-2 of Figure 1.

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a controlled fastening force to a DMD assembly, so that it is held in place between the production steps of the DMD alignment and the final fastening of the screws. It also provides a positive Z-axis impulse to the assembly, to eliminate any slack in that direction. The D'DMD needs are in the correct Z-axis position through the alignment process to keep the image on the screen in focus. In an exemplary embodiment of the present invention, the clamping action is achieved with the use of a stamped steel spring spring. This spring system applies adequate pressure to the DMD to keep it in an appropriate focus, as well as to hold it in place between the alignment and the final hold. In the present design of the light engine, the core optics assembly is fixed in its location. Therefore, it is necessary to adjust the DMD with the optics for the alignment of the image. In accordance with an exemplary modality, the present invention uses a stamped steel part to act as the leaf spring 70, as shown in Figure 1. The spring 70 is compressed by two shoulder screws 95, which apply a predetermined load to a DMD assembly to hold it. with optical housing 2. With this load applied, the DMD assembly has enough freedom to be manipulated by the alignment machine, but will remain in place until the system can be secured. The DMD assembly, as shown in Figure 1, includes a microcircuit DMD (not shown) that is mounted to an intermediate device 20 and operatively connected to a printed circuit board (PCB) 30. An interposed fastener is placed against the intermediate device 20 opposite the PCB 30. The intermediate device 20 is aligned with the PCB 30 and the fastener 10 of the intermediate device by the bolts 21, 22. A backing plate 50 is placed on the PCB 30 opposite the intermediate device 20. with an insulator 40 between the backing plate 50 and the PCB 30. The backing plate 50 has holding structures 51 for use by the alignment machine to hold the DMD assembly. The DMD assembly is held together by first shoulder bolts 90 which pass through the mounting holes in the backing plate 50, the insulator 40 and the PCB 30, and then are screwed into the threaded holes 11 formed in the fastener 10 of the intermediate device. The compression springs 80 are provided in the first shoulder bolts 90 to provide an elastic holding force in the DMD assembly when the first shoulder bolts are tightened. In the embodiment shown in Figure 1, a heat cylinder 52 is provided to transfer heat from the microcircuit DMD: The heat cylinder 52 extends through openings in the back plate 50, the insulator 40 and the PCB 30 , and has a flange 53 resting against the backing plate 50. The heat cylinder is urged against the backing plate 50 by a leaf spring 60 which is held in place by the first shoulder bolts 90.

As shown in Figure 1, the DMD assembly is held in place and driven in the direction of the Z axis by a clamping spring 70. The fastening spring 70 comprises a sheet of elastic material, such as steel, for example. The holding spring 70 has an interconnected plurality of first and second alternating tongues 72, 74 disposed around the periphery of the holding spring 70. In the exemplary embodiment illustrated in Figure 1, the first two tabs 72 and the two second tabs 74 are provided, one of each tab on each end of a rectangular body having an opening for the heat cylinder 52. The first tongues 72 are angled upwards and have mounting slots 73 therein. The second tabs 74 have an angle downwards. When force is applied to the first tabs 72, the clamping spring 70 provides a controlled and consistent clamping force on the second tabs 74. The optical housing 2 has cubes to support the DMD assembly. The threaded holes 4 are formed in the hubs 3. As can best be seen from Figure 2, the first shoulder bolts 90 are hollow, have an opening extended through the first shoulder operation 90 along their length. longitudinal axis. The second shoulder bolts 95 are positioned through the slots 73 in the fastening spring 70 and the openings in the first shoulder bolts 90, then are screwed into the threaded holes 4 in the hubs 3 of the optical housing 2.

In another embodiment of the invention (not illustrated), four leaf springs and four shoulder screws are used to provide the force to the system. In this mode, there is considerable clearance in the force / deflection curves of leaf springs. Because the four springs act independently, there may be more or less force applied in some of their locations. The foregoing illustrates some of the possibilities for practicing the invention. Many other modalities are possible within the scope and spirit of the invention. Therefore, it is intended that the foregoing description be considered as illustrative, rather than limiting and that the scope of the invention is determined by the appended claims, along with its full range of equivalences.

Claims (13)

1. A clamping spring for a micro-deployment, characterized in that it comprises a sheet of elastic material having an interconnected plurality of first and second alternating tabs disposed around the periphery thereof, the first tabs are angled upwards and have mounting slots in the legs. same, the second tongues are angled downwards, whereby the force applied to the first tongues provides a controlled holding force, consisting of the second tongues.

The clamping spring according to claim 1, characterized in that the first and second tongues are interconnected by a generally rectangular body having an opening therethrough.

3. The clamping spring according to claim 1, characterized in that the elastic material is steel.

4. The clamping spring according to claim 1, characterized in that there are two first tongues and two second tongues.

5. A clamping arrangement for a micro-deployment, characterized in that it comprises: a clamping spring, having an elastic material with an interconnected plurality of first and second alternating tabs, arranged around the periphery thereof, the first tabs are angled towards up and have mounting slots therein, the second tabs are angled downwardly, whereby the force applied to the first tabs provides a controlled and consistent holding force to the second tabs; a digital micromirror device (DMD) assembly, secured by a plurality of first shoulder bolts having openings extended along the axes of the bolts; an optical housing having a plurality of cubes that support the digital micromirror device (DMD) assembly with threaded openings therein; and second shoulder bolts disposed through the grooves of the retaining spring and the openings of at least a portion of the first shoulder bolts and engaging the threaded openings of at least a portion of the hubs.

The fastening arrangement according to claim 5, characterized in that the first and second tabs are interconnected by a generally rectangular body having an opening therein.

The fastening arrangement according to claim 5, characterized in that the elastic material is steel.

The fastening arrangement according to claim 5, characterized in that there are two first tongues and two second tongues.

The clamping arrangement according to claim 5, characterized in that the digital micromirror device (DMD) assembly includes a microcircuit of digital micromirror device (DMD) mounted on an intermediate device and electrically connected to a printed circuit board , the intermediate device and the printed circuit board are sandwiched between a backup plate and a fastener of the intermediate device, and the intermediate device is aligned with the printed circuit board and the fastener of the intermediate device by pins.

The clamping arrangement according to claim 9, characterized in that the digital micromirror device (DMD) assembly also includes leaf springs disposed in the first shoulder bolts to drive the digital micromirror device (DMD) assembly together .

11. A projection system, characterized in that , comprising: an optical housing having a plurality of hubs with threaded openings therein; a digital micromirror device assembly (DMD) fastened together with a plurality of first shoulder bolts with a longitudinal opening therethrough; a clamping spring to drive the digital micromirror device (DMD) assembly against the optical housing; and two or more shoulder bolts, which engage the clamping spring, extend through the opening in the selected ones of the first shoulder bolts, and engage with the threaded openings in the optical housing. The projection system according to claim 11, characterized in that the digital micromirror device (DMD) assembly is urged against the optical housing by a clamping spring having a sheet of elastic material with an interconnected plurality of first and second alternating tabs, arranged around the periphery thereof, the first tabs are angled upwards and have mounting grooves therein, the second tabs are angled downwards, whereby, the force applied in the first ones tabs provide a controlled and consistent clamping force to the second tabs. The projection system according to claim 11, characterized in that the digital micromirror device assembly (DMD) is urged against the optical housing by a plurality of leaf springs disposed in at least a portion of the second bolts. of shoulder.