JP2009271141A - Lens shifting device for projector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lens shifting device for shifting a projection lens in up-and-down and right-and-left directions inexpensively. <P>SOLUTION: A slot guide 7 is formed on a shift plate 5 holding a projection lens 6. A bolt 8 is inserted through the slot guide 7 so as to be screwed in a screw hole 9 provided on a front of a holding plate 3 and fastened, thereby holding the shift plate 5 with the holding plate 3. When shifting the projection lens 6, the bolt 8 is loosened to move the shift plate 5 within a range of the slot guide 7, and then the bolt 8 is fastened again, thereby fixing the shift plate 5 with the holding plate 3. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a lens shift device for a projector.

To change the projection position of the image when using the projector, the installation position of the projector body can be changed.However, if the moving space is not enough or it is difficult to install the projector body, The image is projected at an angle. However, when the projector body is tilted, the projection lens is inclined with respect to the screen surface, and the projected image is distorted. In order to cope with this, for example, a projector including a lens shift device as described in Patent Document 1 is known.
JP 2004-317988 A

  The lens shift device of the projector is such that the lens holding plate that holds the projection lens can be moved in two directions, up and down, left and right, relative to the projector body, so that the projection lens can be moved without tilting its optical axis. ing. The projection optical axis connecting the center of the original image in the projector body and the center of the image projected on the screen is tilted, but the optical axis of the projection lens is always oriented perpendicular to the screen surface, so Can project an image without distortion.

  However, in the conventional lens shift device, in order to move the lens holding plate in two directions, up and down, left and right, for example, a support plate that supports the lens holding plate so as to be movable in the vertical direction is further provided. It must be supported so that it can move left and right. Such a shift device is convenient in that the projection lens can be shifted to an arbitrary position within a plane orthogonal to the optical axis, but the structure tends to be complicated, and the number of parts and work man-hours increase, resulting in a significant cost increase. Inevitable.

  The present invention has been made in consideration of the above circumstances. The projection lens can be shifted in two directions orthogonal to the optical axis thereof, and the projection lens can be shifted. An object of the present invention is to provide an advantageous projector lens shift device.

  In order to achieve the above object, the present invention, when trying to move the projector in order to change the projection position of the image of the projector, actually only needs to move the projector in one direction, up and down or left and right. However, the projection lens can be arbitrarily shifted in either the vertical direction or the horizontal direction. For this reason, in the present invention, a shift plate that holds the projection lens and has a shift surface perpendicular to the optical axis formed on the back side is extended in the vertical direction and the horizontal direction perpendicular to the optical axis of the projection lens. At least two slot guides that intersect two slots having a width are formed, and a holding plate that is fixed to the projector main body and has a support surface parallel to the shift surface is formed on the front side. A screw that is exposed to the outside is formed through each formed slot guide. Then, a tightening member having a head having a diameter larger than the slot width is screwed into each of the exposed screws through the respective slot guides, and tightened so that the shift plate is interposed between the head and the holding plate. It is clamped and fixed.

  When a female screw formed on the support surface is used as the screw on the holding plate side, the fastening member is a fastening bolt in which a male screw portion that is screwed to the female screw is formed on the tip side. When a male screw is used as the screw on the holding plate side, a nut having a female screw portion formed on the head is used as the fastening member. Furthermore, it is also effective to provide a restriction protrusion on the holding plate that protrudes forward from the support surface and engages with the inner peripheral wall of the slot of the shift plate, and restricts the movement direction of the shift plate in one of the two directions. In this case, the female screw or the male screw is provided on the front end surface of the restricting protrusion. The slot guides formed on the shift plate are preferably provided at at least two positions that are symmetric with respect to the optical axis of the projection lens.

  According to the present invention, it is possible to arbitrarily shift the projection lens of the projector to either the vertical direction or the horizontal direction orthogonal to the optical axis without complicating the structure, thereby reducing the manufacturing cost of the projector. However, a highly practical lens shift device can be provided.

  In FIG. 1 schematically showing the front side of a projector using the present invention, a holding plate 3 is fixed to the front side of the projector body 2 with bolts 4, and a shift plate 5 is held on the front side of the holding plate 3. . A projection lens 6 is fixed to the shift plate 5 and a pair of slot guides 7 having the same cross shape are formed. As shown in FIG. 2, bolts 8 are respectively attached to the holding plate 3 through the slot guides 7. The shift plate 5 is fixed to the holding plate 3 by screwing into the screw holes 9 and tightening. Each of these components constitutes a shift device for the projection lens 7.

  The front surface of the holding plate 3 is a support surface that supports the back surface of the shift plate 5, and the back surface of the shift plate 5 is a shift surface that is in sliding contact with the support surface of the holding plate 3. The plane is orthogonal to the axis P. When the shift plate 5 is fixed to the holding plate 3 by tightening the bolts 8, the support surface and the shift surface are brought into close contact with each other, and the optical axis P of the projection lens 6 is kept horizontal. Further, when the bolt 8 is loosened, the shift plate 5 can be moved in the vertical or horizontal direction along the vertical slot 7a or the horizontal slot 7b, and the projection lens 6 is moved along with the movement. Note that the difference between the outer diameter of the bolt 8 and the slot width of the slots 7a and 7b is 0.5 mm so as to suppress rattling when the shift plate 5 is moved and the position when the shift plate 5 is fixed does not vary greatly. It is about 0.8mm.

  Since the two slots 7a and 7b having the same slot width intersect each other at the center, the slot guide 7 has a cross shape. However, the slot guides 7 intersect each other to be L-shaped. Is also possible. Further, the pair of slot guides 7 may be provided at least at any two positions of the shift plate 5, but as shown in the figure, the slot guides 7 are provided at at least two positions having a rotational symmetry of 180 ° with respect to the optical axis P of the projection lens 6. It is good. Of course, the screw hole 9 provided on the support surface of the holding plate 3 is also provided at a position corresponding to the position of the slot guide 7. Further, in addition to the two slots 7 a and 7 b, a slot extended in a 45 ° oblique direction may be added so that the projection lens 6 can be moved in the oblique direction together with the shift plate 5.

  Hereinafter, the operation of the above configuration will be described. As shown in FIG. 3A, in the reference state in which the shift plate 5 is fixed to the holding plate 3 with the bolt 8 inserted through the center of the slot guide 7, the center Q of the liquid crystal display panel incorporated in the projector body 2 is projected. Since it is located on the optical axis P of the lens 6, projection is performed so that the center of the projected image is also located on the optical axis P of the projection lens 6. If the screen is displaced upward with respect to the position of the image projected in this reference state, the projector main body 2 may be simply placed on the base, for example. For this, the shift plate 5 may be moved upward.

  The shift plate 5 can be easily moved upward by loosening the pair of bolts 8. At this time, since the outer diameter of the bolt 8 is set such that there is no excess backlash between the inner wall of the slot 7a, a guide action is obtained by the pair of bolts 8 and the inner peripheral wall of each slot 7a. It becomes possible to move the plate 5 correctly only in the vertical direction.

  If the bolt 8 is tightened after the shift plate 5 is moved by an appropriate amount in accordance with the position of the screen, the shift plate 5 is sandwiched between the head of the bolt 8 and the holding plate 3, as shown in FIG. The shift plate 5 can be fixed at that position. The projection optical axis connecting the center Q of the liquid crystal display panel and the center of the image projected on the screen is inclined with respect to the optical axis P of the projection lens 6 as indicated by the broken line, but an image without distortion is displayed on the screen. Can be projected. If the projector main body 2 cannot be installed by moving in the left-right direction, the shift plate 5 may be moved left-right using the slot 7b extending in the horizontal direction.

  In particular, when the shift plate 5 is moved in the vertical direction and adjusted in position, there is a concern that the shift plate 5 may fall or gradually descend if the bolts 8 are weakly tightened. It is desirable to provide a knob 8a on the head of the bolt 8 so that the tightening operation can be performed easily. In addition, as shown in FIG. 4A, it is also effective to form a slope 12 on the entire front end edge of the slot guide 7 and to form a slope 13 corresponding to the slope 12 on the head of the bolt 8. Is. In the process of tightening the bolt 8, the slopes 12 and 13 come into close contact with each other as shown in FIG. 5B, and the shift plate 5 can be pressed toward the holding plate 3 with a stronger pressing force. And the clamping force can be increased.

  5 and 6 show an example in which the restriction projection 15 is protruded from the support surface of the holding plate 3 and the screw hole 9 is provided on the front end surface thereof, and the other screw hole 9 provided in a pair has the same configuration. is there. The outer diameter of the restricting projection 15 is slightly smaller than the slot width of the slot guide 7 so that there is no excess backlash between the inner wall of the slot and the protrusion of the bolt 8 in the same manner as the outer diameter of the bolt 8 in the previous embodiment. The length is less than the thickness of the shift plate 5. Therefore, as shown in FIG. 6, the restricting projection 15 is partially inserted into the slot guide 7, and even if the bolt 8 is completely removed from the female screw in the screw hole 9, the shift plate 5 remains in a pair. It is in a state of being supported by the restriction protrusion 15. Thereby, when the shift plate 5 is moved, a good guide action can be obtained, and there is no possibility that the shift plate 5 may be accidentally dropped during the adjustment.

  In each of the above embodiments, the screw of the holding plate 3 is used as a female screw, and the bolt 8 is used as a fastening member that fastens and holds the shift plate 5 from the front side of the shift plate 5, and the male screw formed at the tip of the bolt 8. The shift plate 5 is fixed to the adjustment position by screwing and tightening to the female screw on the holding plate 3 side. However, as shown in FIGS. 7 and 8, a male screw is provided on the holding plate 3 side to It is also possible to adopt a configuration in which the nut is screwed from the front side.

  In FIG. 7, the restricting projection 15 shown in FIG. 5 is formed on the support surface of the holding plate 3 and partially fits into the slot guide 7 of the shift plate 5 to similarly prevent the shift plate 5 from being accidentally dropped. It is out. When the male screw 18 protrudes from the front end surface of the restricting protrusion 15 and the back surface (shift surface) of the shift plate 5 is brought into close contact with the support surface of the holding plate 3 as shown in FIG. It protrudes to the front.

  A female screw 19a is cut in a nut 19 used as a fastening member. After adjusting the position of the shift plate 5, the nut 19 is fastened to the male screw 18 to hold the shift plate 5 as shown in FIG. The shift plate 5 can be sandwiched between the nut 19 and the holding plate 3 by being pressed toward the plate 3. A knob 19b is preferably provided on the front surface of the nut 19 so that the nut 19 can be easily tightened. In order to increase the tightening force, the inclined surfaces 12, 13 as shown in FIG. You may form in the front end edge of the guide 7, and the back side of the nut 19. FIG.

  As described above, according to the illustrated embodiment, for example, the front plate of the projector body 2 is used as the holding plate 3, or the movement position of the shift plate 5 is a sensor so that the shift plate 5 can be moved electrically. It is also possible to drive with a motor while monitoring. In addition, at least a vertical slot 7a and a horizontal slot 7b are used for the slot guide 7 so that the projection lens 6 can be shifted from the reference state in at least the vertical direction and the horizontal direction. It is also possible to extend the slots further in the oblique direction and the orthogonal direction at both ends of the slots 7a and 7b.

It is a front view which shows the outline of the front structure of a projector. It is a disassembled perspective view which shows the outline of the front structure of a projector. It is operation | movement explanatory drawing when a projection lens is moved to the orthogonal | vertical direction. It is principal part sectional drawing which shows the modification of a volt | bolt and a slot guide. It is a principal part perspective view which shows the example which provided the screw hole for shift plate fixation in the front-end surface of a control protrusion. It is principal part sectional drawing when a shift plate is fixed by the structure of FIG. It is a principal part perspective view which shows the example which provided the external thread in the holding plate side. It is principal part sectional drawing when a shift plate is fixed by the structure of FIG.

Explanation of symbols

2 Projector body 3 Holding plate 5 Shift plate 6 Projection lens 7 Slot guide 8 Bolt 9 Screw hole 15 Restriction protrusion 18 Male screw 19 Nut

Claims (6)

In a lens shift device for a projector that supports a projection lens so as to be movable in two directions of a vertical direction and a horizontal direction orthogonal to the optical axis thereof,
A slot guide that holds the projection lens, has a shift surface orthogonal to the optical axis formed on the back side, and intersects two slots of the same slot width that are respectively extended in the two directions. Shift plates formed in two places;
A holding plate that is fixed to the projector main body, a support surface parallel to the shift surface is formed on the front surface side, and a screw that is exposed to the outside through each of the slot guides;
The shift plate is sandwiched between the head and the holding plate by having a head having a diameter larger than the slot width, screwed into each of the exposed screws through the respective slot guides, and tightened. A clamping member;
A lens shift device for a projector, comprising:   2. The screw according to claim 1, wherein the screw is a female screw having a screw hole exposed on the support surface, and the fastening member is a bolt having a male screw portion that is screwed into the female screw on a tip side. Projector lens shift device.   The holding plate is provided with a restriction projection that protrudes forward from the support surface, engages with the inner peripheral wall of the slot, and restricts the movement direction of the shift plate in one of the two directions, and the front end surface of the restriction projection The projector lens shift device according to claim 2, wherein the screw hole is provided in the projector.   2. The projector according to claim 1, wherein the screw is a male screw protruding forward from the support surface, and the fastening member is a nut having a female screw portion formed on the head to be screwed into the male screw. Lens shift device.   The holding plate is provided with a restriction projection that protrudes forward from the support surface, engages with the inner peripheral wall of the slot, and restricts the movement direction of the shift plate in one of the two directions, and the front end surface of the restriction projection The projector lens shift device according to claim 4, wherein the male screw protrudes from the projector.   6. The lens shift device for a projector according to claim 1, wherein the slot guide is formed at two positions which are symmetrical with respect to the optical axis of the projection lens.

Images