JP2011133520A - Lens device of projector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent an unwanted shake of a picture on a screen so as to eliminate failure in which quality of the picture is spoiled, and to achieve improvement in easiness and cost performance in terms of eliminating the failure. <P>SOLUTION: When constituting the lens device 1 of the projector P which performs focusing adjustment by meshing a pinion part 6 provided on a rotary shaft 5s of a focusing motor 5 with a rack part 4 provided in a periphery direction of an outer periphery part 3s of a focus ring 3 supporting a focusing lens part 2, and turning the focus ring 3 by the focusing motor 5, a separation part Sm mechanically separating the focusing lens part 2 side and the rack part 4 side is provided between the focusing lens part 2 and the rack part 4, and an elastic member 7 is made to lie in the separation part Sm, whereby the focusing lens part 2 side is coupled with the rack part 4 side. Thus, the lens device 1 is constituted such that the focusing lens part 2 and the rack part 4 can be relatively elastically displaced. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a projector lens apparatus including an electric focusing mechanism that performs focusing adjustment by rotating a focus ring by a focusing motor.

  In general, a projector is equipped with a lens device for projection. In particular, in an electric lens device that can perform focusing by remote control (remote control) or the like, the circumferential direction of the outer peripheral portion of a focus ring that supports the focusing lens portion And an electric focusing mechanism that adjusts the focusing by rotating the focus ring by the operation of the focusing motor, by engaging the pinion portion provided on the rotating shaft of the focusing motor.

  Conventionally, as a lens device (projector) provided with such an electric focusing mechanism, a lens device disclosed in Patent Document 1 is known, and in the same document 1, a gear portion is provided on an outer peripheral portion. A projection lens that is moved in the optical axis direction according to the rotation state of the gear unit, a drive motor that rotationally drives the gear unit, an operation unit for adjusting the position of the projection lens in the optical axis direction, and the operation unit A projector (lens driving device) is described that includes an input state and a duration time of the input state, and a CPU that drives and controls the rotation direction of the drive motor and the continuous drive time according to the detection result. .

JP 2006-106581 A

  However, the lens device provided in the above-described conventional projector has the following problems.

  First, when the drive motor starts to rotate, an unnecessary shake may occur in the lens device due to a shock (impact). This phenomenon rarely occurs when the lens unit is small, but when the lens unit becomes large and its weight (moment) increases, the focus ring follows smoothly even if the drive motor starts rotating. In addition, since there is a gear meshing portion between the drive motor and the focusing lens portion, the lens device will not be shaken. In particular, the shake of the lens device causes the screen to shake on the screen, which impairs the screen quality. This problem becomes apparent due to the mounting of various interchangeable lenses accompanying the enlargement of projectors and the commercialization of interchangeable lens types, and becomes an important issue that cannot be ignored in the case of commercial projectors.

  Secondly, in order to suppress such a phenomenon of impact as much as possible, it is possible to take measures such as increasing the mechanical accuracy of the lens apparatus or increasing the rigidity of the projector body. However, in order to obtain a sufficient suppression effect, there are difficulties from the viewpoint of ease of implementation and low cost, such as the need for appropriate costs, and there are limits to taking measures.

  An object of the present invention is to provide a lens device for a projector that solves the problems existing in the background art.

  In order to solve the above-described problems, the present invention is provided on the rotating shaft 5s of the focusing motor 5 on the rack part 4 provided along the circumferential direction of the outer peripheral part 3s of the focus ring 3 that supports the focusing lens part 2. When the lens device 1 of the projector P including the electric focusing mechanism Mf that engages the pinion unit 6 and rotates the focus ring 3 by the operation of the focusing motor 5 to perform the focusing adjustment, the focusing lens unit 2 and the rack unit are configured. 4 is provided with a separating portion Sm that mechanically separates the focusing lens portion 2 side and the rack portion 4 side, and an elastic member 7 is interposed in the separating portion Sm so that the focusing lens portion 2 side and the rack portion 4 side are separated. Combined, the focusing lens part 2 and the rack part 4 are configured to be relatively elastically displaceable. It is characterized in.

  In this case, according to a preferred aspect of the invention, the focus ring 3 is divided into a front ring portion 3f and a rear ring portion 3r, and an elastic member 7 is interposed in the axial direction Fa between the front ring portion 3f and the rear ring portion 3r. In addition, they are coupled so as to be relatively elastically displaceable over a predetermined range in the axial direction Fa, and can be relatively displaced over a predetermined range by providing a predetermined clearance Cr in the radial direction Fr between the front ring portion 3f and the rear ring portion 3r. Alternatively, the lens holder 8 that supports the focusing lens portion 2 disposed inside the focus ring 3 and the focus ring 3 may be configured separately, and between the focus ring 3 and the lens holder 8. The axial Fa elastic member 7 is interposed, and coupled to be relatively elastically displaceable over a predetermined range in the axial direction Fa. By providing a predetermined clearance Cr radially Fr between the ring 3 and the lens holder 8, it may be displaceable relative configured over a predetermined range. Further, it is possible to provide a pressure adjusting unit 9 that can adjust the magnitude of the pressure applied by the elastic member 7. Further, an elastic member 7e can be interposed in the clearance Cr.

  The projector lens apparatus 1 according to the present invention having such a configuration has the following remarkable effects.

  (1) Since the elastic member 7 is interposed in the separation part Sm between the focusing lens part 2 and the rack part 4, even when a shock (impact) occurs when the focusing motor 5 starts rotating, The impact can be effectively absorbed by the elastic member 7. Thereby, the propagation of the impact to the focusing lens unit 2 side can be blocked, and unnecessary screen shaking on the screen can be prevented, and the problem that the screen quality is impaired can be solved. In particular, when the lens apparatus 1 is increased in size (weight increase), a greater effect can be obtained.

  (2) Basically, it is sufficient to interpose the elastic member 7 between the focusing lens portion 2 and the rack portion 4, so that it can be easily implemented with a small number of parts and a partial improvement. Therefore, other measures such as increasing the mechanical accuracy of the lens device 1 and increasing the rigidity of the projector body are almost unnecessary, and the ease of implementation and low cost are excellent.

  (3) According to a preferred embodiment, the focus ring 3 is divided into a front ring portion 3f and a rear ring portion 3r, and an elastic member 7 is interposed in the axial direction Fa between the front ring portion 3f and the rear ring portion 3r, and It is configured to be relatively elastically displaceable over a predetermined range in the axial direction Fa and to be relatively displaceable over a predetermined range by providing a predetermined clearance Cr in the radial direction Fr between the front ring portion 3f and the rear ring portion 3r. In this case, the elastic member 7 can be disposed at a position closer to the focusing motor 5 (rack portion 4), so that the effect related to shock absorption can be further enhanced.

  (4) According to a preferred embodiment, the lens holder 8 that supports the focusing lens portion 2 disposed inside the focus ring 3 and the focus ring 3 are configured separately, and an axis between the focus ring 3 and the lens holder 8 is formed. By interposing the elastic member 7 in the direction Fa and being coupled to be relatively elastically displaceable over a predetermined range in the axial direction Fa, and providing a predetermined clearance Cr in the radial direction Fr between the focus ring 3 and the lens holder 8 Since the elastic member 7 can be disposed between the lens holder 8 and the focus ring 3 that are often originally configured separately if configured so as to be relatively displaceable over a predetermined range, further facilitating the implementation. Can contribute.

  (5) According to a preferred embodiment, if the pressure adjusting unit 9 capable of adjusting the magnitude of the pressure applied by the elastic member 7 is provided, the magnitude of the pressure is optimized according to the use state and the like, and the shock absorption is related. The effect can be further enhanced.

  (6) According to a preferred embodiment, if the elastic member 7e is interposed in the clearance Cr, the positional stability and accuracy in both the radial direction Fr and the axial direction Fa on the focusing lens unit 2 side and the rack unit 4 side are improved. Can be increased.

Plan sectional drawing of the lens apparatus which concerns on suitable embodiment of this invention, The partial extraction enlarged view of the A section in FIG. 1 which shows the principal part of the lens apparatus, The partial extraction enlarged view of the A section in FIG. 1 which shows the example of a change of the principal part of the lens apparatus, Partially extracted exterior side view with a part broken away showing the main part of the lens device, Appearance front view in which a part of the lens device is broken, The partial extraction enlarged view of the A section in FIG. 1 which shows the other modification of the principal part of the lens apparatus, Side view of a projector equipped with the lens device, Plan sectional drawing of the lens apparatus which concerns on the modified embodiment of this invention, The partial extraction enlarged view of the B section in FIG. 8 showing the main part of the lens device, The partial extraction enlarged view of the B section in FIG. 8 showing a modification example of the main part of the lens device,

  Next, preferred embodiments according to the present invention will be given and described in detail with reference to the drawings.

  First, an overall schematic configuration of the lens apparatus 1 according to the present embodiment will be described with reference to FIG.

  The lens apparatus 1 includes a lens barrel 11, and a plurality of lens groups Lf, La, Lb, Lc, and Lr are accommodated in the lens barrel 11. In this case, the lens group Lf located on the foremost side is the focusing lens unit 2. Each lens group Lf, La... Lr includes one or more lenses. The exemplary lens groups Lf... Lr are five groups, but the number of groups is arbitrary.

  The lens barrel 11 includes a fixed cylinder portion 12. The fixed cylinder portion 12 includes an inner cylinder portion 12i and an outer barrel portion 12o. The cam barrel portion 13 is rotated inside the inner cylinder portion 12i. It can be moved freely. The cylindrical body of the inner cylinder portion 12i has a plurality of linear grooves 14 formed along the front-rear direction (axial direction) and arranged at equal intervals in the circumferential direction, and the cylindrical body of the cam cylinder portion 13 Has a plurality of cam grooves 15aa ..., 15ab ..., 15b ..., 15c ... formed along the spiral direction. Further, a zoom ring 16 is rotatably disposed at an axially intermediate position on the outer peripheral surface of the inner cylindrical portion 12i, and the cylindrical body of the inner cylindrical portion 12i is disposed in a direction perpendicular to the axial direction (circumferential direction). The guide grooves 17 corresponding to the rotation range of the zoom ring 16 are formed. The roller members 18 are accommodated in the guide grooves 17, and the zoom ring 16 and the cam cylinder portion 13 are connected by the roller members 18. On the other hand, a plurality of lens group frames 19aa, 19ab, 19b, 19c are accommodated inside the cam tube portion 13, projecting radially from the outer peripheral surface of each lens group frame 19aa, and arranged at equal intervals in the circumferential direction. The plurality of roller members 20aa ..., 20ab ..., 20b ..., 20c ... are respectively formed in the cam grooves 15aa ..., 15ab ..., 15b ..., 15c ... of the cam cylinder portion 13 and the linear grooves 14 ... of the inner cylinder portion 12i. Engage.

  A rack portion 21 is provided along the circumferential direction on the outer peripheral portion 16s of the zoom ring 16, and a zooming motor 22 is attached using the outer peripheral surface of the outer cylinder portion 12o. The pinion portion 23 provided on the rotary shaft 22 s of the zooming motor 22 is engaged with the rack portion 21. Accordingly, if the zooming motor 22 is operated, the zoom ring 16 can be rotated, and the rotational displacement of the zoom ring 16 is transmitted to the cam cylinder portion 13 through the roller members 18. As a result, the lens group frames 19aa, 19ab, 19b, 19c are displaced in the front-rear direction, and zooming adjustment of the lens device 1 can be performed. The lens group frames 19aa are assembled in the same manner, but the inclination angles of the cam grooves 15aa corresponding to the lens group frames 19aa are set to be the same or different. The above configuration is the electric zooming mechanism Mz. On the other hand, an electric focusing mechanism Mf that constitutes a main part of the present invention is disposed in front of the zoom ring 16.

  Next, the electric focusing mechanism Mf constituting the main part of the lens device 1 according to the present embodiment will be described with reference to FIGS.

  The focus ring 3 is rotatably disposed at a position in front of the zoom ring 16 on the outer peripheral surface of the inner cylinder portion 12 i and in the vicinity of the zoom ring 16. The front end of the focus ring 3 projects forward from the front end of the inner cylinder portion 12i, and the lens holder 8 is fixed to the inner peripheral surface of the front portion of the focus ring 3 with screws 31. And the focusing lens part 2 which is the lens group Lf located in the foremost side is supported by the inner peripheral part of the lens holder 8. Further, a helicoid screw (male side screw) 32m provided at the rear portion of the outer peripheral portion of the lens holder 8 is screwed into a helicoid screw (female side screw) 32f provided at the front portion of the inner peripheral portion of the inner cylinder portion 12i.

  Further, the focusing motor 5 is attached using the outer peripheral surface of the outer cylinder portion 12o, and the pinion portion 6 is provided on the rotating shaft 5s of the focusing motor 5. In this case, as shown in FIG. 5, the focusing motor 5 is disposed at a position 180 ° opposite to the zooming motor 22. On the other hand, a rack part 4 is provided along the circumferential direction at the rear part of the outer peripheral part 3 s of the focus ring 3, and the pinion part 6 is engaged with the rack part 4. The above is the basic configuration of the electric focusing mechanism Mf. Thereby, if the focusing motor 5 is operated, the focus ring 3 can be rotated, and the rotation displacement of the focus ring 3 becomes the rotation displacement of the lens holder 8. Since the lens holder 8 has the helicoid screw 32m screwed into the helical screw 32f of the inner cylinder portion 12i, the focus ring 3 is displaced in the front-rear direction in response to the rotational displacement of the lens holder 8, and the focusing adjustment of the lens device 1 is performed. It can be performed. Since the focus ring 3 is rotated and displaced and also moves in the front-rear direction, the length in the width direction (axial length) of the rack portion 4 is a length that allows the focus ring 3 to move in the front-rear direction. Set to (width).

  Incidentally, as is apparent from FIG. 1, the focusing lens unit 2 is usually the lens group Lf located on the foremost side of the lens device 1 and has the largest weight. Further, since the rotation of the focusing motor 5 is transmitted to the focus ring 3 through the pinion portion 6 and the rack portion 4, when the weight (moment) on the focusing lens portion 2 side becomes large, the focusing motor 5 Even when 5 starts to rotate, the focusing lens unit 2 side hardly follows, and eventually a shock (impact) is generated on the focus ring 3 side, and the lens apparatus 1 is shaken.

  For this reason, in the lens apparatus 1 according to the present embodiment, in order to absorb the impact at this time, the focusing lens unit 2 side and the rack unit 4 side are mechanically separated between the focusing lens unit 2 and the rack unit 4. A portion Sm is provided, and an elastic member 7 is interposed in the separation portion Sm so that the focusing lens portion 2 side and the rack portion 4 side are coupled, and the focusing lens portion 2 and the rack portion 4 are configured to be relatively elastically displaceable.

  In this case, as shown in FIG. 1, the focus ring 3 is configured in a two-part form of a front ring portion 3f and a rear ring portion 3r. Accordingly, a separation portion Sm is formed between the rear end portion of the front ring portion 3f and the front end portion of the rear ring portion 3r. As shown in FIG. 1, it is desirable that the separation portion Sm be selected as close to the rack portion 4 as possible in order to obtain a more effective shock absorbing action. FIG. 2 shows a partial extraction enlarged view of part A in FIG. As shown in FIG. 2, a large-diameter flange portion 34 into which the insertion portion 33 provided at the rear end of the front ring portion 3f can be inserted is formed at the front end portion of the rear ring portion 3r. The flange portion 34 is composed of a raised portion 34s raised perpendicularly to the radial direction Fr from the front end of the rear ring portion 3r, and a cylindrical portion 34c protruding forward from the leading end of the raised portion 34s. The insertion portion 33 can be inserted into the. At this time, a slight clearance Cr is provided in the radial direction Fr between the insertion portion 33 and the cylindrical portion 34c, so that relative displacement can be achieved over a predetermined range. Further, the insertion portion 33 is formed thick, and screw hole portions 35 are formed in the radial direction from the outer peripheral surface. In this case, as shown in FIG. 5, a plurality of screw hole portions 35 are provided at equal intervals in the circumferential direction. A plurality of restricting hole portions 36 corresponding to these screw hole portions 35 are formed in the cylindrical portion 34c.

  On the other hand, regulating screws 37 are provided to be screwed into the screw holes 35. The restriction screws 37 have cylindrical heads 37h accommodated in the restriction holes 36, and the outer diameter of the heads 37h is larger than the inner diameter of the restriction holes 36 as shown in FIG. And a predetermined clearance (play) Ca is provided between the heads 37h and the restriction holes 36. As a result, the front ring portion 3f and the rear ring portion 3r can be relatively displaced in the axial direction Fa over a predetermined range. Furthermore, the elastic member 7 interposed between the raising portion 34 s and the insertion portion 33 is prepared. The illustrated elastic member 7 is integrally formed as a donut-shaped rubber ring 7g by a rubber material having a predetermined elasticity. For this reason, a holding recess 38 capable of holding the rubber ring 7g is provided in a ring shape along the circumferential direction on the inner surface (front surface) of the raised portion 34s.

  Such a focus ring 3 can be assembled as follows. First, the rubber ring 7g is fitted into the flange portion 34, that is, the holding recess 38. Then, the insertion portion 33 of the front ring portion 3f is inserted inside the flange portion 34, that is, inside the cylinder portion 34c. Screw on. FIG. 2 shows this state. Thereby, the front ring part 3f located on the focusing lens part 2 side and the rear ring part 3r located on the rack part 4 side are coupled via the rubber ring 7g disposed in the separation part Sm. The rubber ring 7g between the flange portion 34 and the insertion portion 33 is compressed and interposed.

  In this way, the focus ring 3 is divided into the front ring portion 3f and the rear ring portion 3r, the compressed rubber ring 7g is interposed in the axial direction Fa between the front ring portion 3f and the rear ring portion 3r, and It is configured to be relatively elastically displaceable over a predetermined range in the axial direction Fa and to be relatively displaceable over a predetermined range by providing a predetermined clearance Cr in the radial direction Fr between the front ring portion 3f and the rear ring portion 3r. In this case, the rubber ring 7g can be disposed at a position closer to the focusing motor 5 (rack portion 4), so that the effect related to shock absorption can be further enhanced.

  On the other hand, FIG. 3 shows a rubber ring 7e according to a modified example of the rubber ring 7g. The rubber ring 7e according to the modified example is obtained by interposing a compressed thin second rubber ring portion 7es in the clearance Cr between the cylindrical portion 34c and the insertion portion 33 with respect to the rubber ring 7g described above. The rubber ring 7e is obtained by integrally forming the second rubber ring portion 7es with the rubber ring 7g described above. If such a rubber ring 7e is used, the positional stability and accuracy in both the radial direction Fr and the axial direction Fa on the focusing lens portion 2 side and the rack portion 4 side can be further increased.

  FIGS. 6A and 6B show another modification of the elastic member 7. FIG. 6A shows the use of springs 7 s... As the elastic member 7. The springs 7s are arranged corresponding to the positions where the screw holes 35 are provided. Even in this modified example, it is the same as the case where the rubber ring 7g described above is interposed, the compressed springs 7s are interposed between the flange portion 34 and the insertion portion 33, and the inner surface of the starting portion 34s is Holding recesses 39 having a circular cross section capable of holding the springs 7s are provided in correspondence with the restricting holes 36. The illustrated springs 7s are coil springs, but various other springs such as leaf springs and wave washers can be used.

  6 (b) is provided with a pressure adjusting section 9 capable of adjusting the magnitude of the pressure applied by the elasticity of each spring 7s (elastic member 7) in addition to each spring 7s shown in FIG. 6 (a). It is. For this reason, screw hole portions 40 penetrating from the center of the holding recesses 39 to the outer surface (rear surface) of the raised portion 34s are formed, and the adjusting screws 41 from the outer surface side of the raised portion 34s are formed in the screw hole portions 40. Are screwed together, and spring receivers 42 are interposed between the tips of the adjustment screws 41 exposed (projected) in the holding recesses 39 and the springs 7s accommodated in the holding recesses 39, respectively. Accordingly, if the adjusting screws 41 are turned with a screwdriver or the like, the spring receiving plates 42 can be moved back and forth in the axial direction Fa, so that the degree of compression of the springs 7s can be changed. Providing such a pressure adjusting unit 9 can optimize the magnitude of the pressure depending on the use state and the like, and can further enhance the effect relating to shock absorption.

  Next, the operation (function) of the electric focusing mechanism Mf included in the lens device 1 according to the present embodiment will be described with reference to FIGS.

  The illustrated lens device 1 is an interchangeable lens, and the rear portion of the fixed cylinder portion 12 can be attached to and detached from the projector P shown in FIG. Since the projector P modulates and projects the luminous flux emitted from the light source unit according to image information, the projector P is often installed on a ceiling using a support unit 61 as shown in FIG. Accordingly, in this case, focusing adjustment can be performed using a remote controller or the like that is not shown.

  At the time of focusing adjustment, the focusing motor 5 operates, and the pinion portion 6 provided on the rotating shaft 5s rotates. Thereby, the rack part 4 meshing with the pinion part 6 is also rotationally displaced, and the integral focus ring 3 is also rotated. Due to the rotational displacement of the focus ring 3, the integral lens holder 8 is also rotationally displaced. At this time, since the helicoid screw 32m of the lens holder 8 is screwed into the helicoid screw 32f of the inner cylinder portion 12i, when the focus ring 3 is rotated and displaced, the helicoid screw 32m is moved in the front-rear direction corresponding to this rotation. Displace. That is, the focusing adjustment of the lens apparatus 1 can be performed.

  On the other hand, as described above, when the lens apparatus 1 is large, when the stopped focusing motor 5 starts to rotate, the focus ring 3 is difficult to follow, so a shock (impact) is generated on the focus ring 3 side. appear. However, according to the lens device 1 according to the present embodiment, the front ring portion 3f on the focusing lens portion 2 side and the rear ring portion 3r on the rack portion 4 side have a predetermined range in the axial direction Fa (corresponding to the clearance Ca). ) Over a predetermined range (corresponding to the clearance Cr) in the radial direction Fr. A rear ring portion 3r indicated by an imaginary line in FIG. 2 shows a state in which the rear ring portion 3r is relatively elastically displaced.

  Therefore, even when a shock (impact) occurs when the focusing motor 5 starts to rotate, the impact can be effectively absorbed by the rubber ring 7g. Thereby, the propagation of the impact to the focusing lens unit 2 side can be blocked, and unnecessary screen shaking on the screen can be prevented, and the problem that the screen quality is impaired can be solved. In particular, when the lens device 1 is increased in size (weight increased), a greater effect can be obtained. Further, basically, it is sufficient to interpose the rubber ring 7g between the focusing lens portion 2 and the rack portion 4, so that it can be easily implemented with a small number of parts and some improvements, and the mechanical accuracy of the lens device 1 is improved. It is excellent in ease of implementation and low cost because other measures such as improving the rigidity of the projector and the rigidity of the projector main body are almost unnecessary.

  Next, a lens device 1 according to a modified embodiment of the present invention will be described with reference to FIGS.

  As shown in FIG. 8, the lens device 1 according to the modified embodiment is obtained by changing the position where the elastic member 7 is interposed. Therefore, in the lens apparatus 1 shown in FIG. 8, the focus ring 3 is integrally formed. That is, unlike the embodiment shown in FIG. 1, the front ring portion 3f and the rear ring portion 3r are not divided into two parts. In the lens apparatus 1 shown in FIG. 8, a separation unit Sm is provided between the lens holder 8 that supports the focusing lens unit 2 and the focus ring 3. Usually, since the lens holder 8 that supports the focusing lens unit 2 and the focus ring 3 are often configured separately, the lens holder 8 and the focus ring 3 are connected to the focusing lens unit 2 side by a slight shape change or the like. It can be used as a separation part Sm that mechanically separates the rack part 4 side.

  9 and 10 show enlarged partial extraction views of part B in FIG. Normally, when the focus ring 3 and the lens holder 8 are coupled, a ring-shaped coupling convex portion 45 protruding in the center direction is provided on the inner peripheral portion of the focus ring 3, and in the radial direction on the outer peripheral portion of the lens holder 8. Protruding ring-shaped coupling projections 46 are provided, and at the time of assembly, the tips of the coupling projections 45 and the tips of the coupling projections 46 are brought into contact with each other, so that a plurality of positions at equal intervals in the circumferential direction are fixed to the fixing screws 31. To fix (couple). For this reason, as shown in FIG. 9, an engagement piece 45 s is formed so as to protrude from one coupling convex portion 45, and a notch 46 s is formed in the other coupling convex portion 46. The elastic member 7 is interposed between the portions 45s. Further, the inner diameter of the insertion hole portion 48 provided in the focus ring 3 through which the fixing screws 31 are inserted is formed to be larger than the outer diameter of the portion of the fixing screw 31 to be inserted, and the insertion hole portion 48 and the fixing screw are formed. A predetermined clearance (play) Ca is provided between 31. Thereby, the elastic member 7 can be compressed and interposed with respect to the axial direction Fa between the lens holder 8 on the focusing lens portion 2 side and the focus ring 3 on the rack portion 4 side. The part 4 can be relatively elastically displaced over a predetermined range in the axial direction Fa (corresponding to the clearance Ca). Further, the outer diameter of the coupling convex portion 46 is selected to be smaller than the inner diameter of the coupling convex portion 45, and a predetermined clearance Cr is provided between the coupling convex portion 45 and the coupling convex portion 46. As a result, the lens holder 8 and the rack portion 4 can be relatively displaced over a predetermined range in the radial direction Fr (corresponding to the clearance Cr).

  9 shows an example using springs 7 s... As the elastic member 7, and FIG. 10 shows an example using a rubber ring 7 g as the elastic member 7. The basic configuration can be implemented in the same manner as the embodiment shown in FIGS. Accordingly, in FIGS. 9 and 10, the same components as those in FIGS. 1 to 6 are denoted by the same reference numerals to clarify the configuration, and detailed description thereof is omitted.

  Thus, the lens holder 8 that supports the focusing lens portion 2 disposed inside the focus ring 3 and the focus ring 3 are configured separately, and in the axial direction Fa between the focus ring 3 and the lens holder 8, By interposing a compressed elastic member 7 and being relatively elastically displaceable over a predetermined range in the axial direction Fa, and providing a predetermined clearance Cr in the radial direction Fr between the focus ring 3 and the lens holder 8 Even if it is configured to be capable of relative displacement over a predetermined range, the same function (action) as that shown in FIG. 6A can be exhibited. According to the modified embodiment of FIG. 8, the elastic member 7 can be disposed between the lens holder 8 and the focus ring 3 that are often configured separately from each other, which can contribute to further ease of implementation. .

  The preferred embodiment (modified embodiment) has been described in detail above. However, the present invention is not limited to such an embodiment, and the gist of the present invention in the configuration, shape, material, quantity, and the like of details. Any change, addition, or deletion can be made without departing from. For example, the focus ring 3 is divided into a front ring portion 3f and a rear ring portion 3r, and an elastic member 7 is disposed between the front ring portion 3f and the rear ring portion 3r, and between the focus ring 3 and the lens holder 8. Although two forms in the case of arranging the elastic member 7 are shown, only one of them may be carried out, or a combination of both may be carried out. Moreover, although the example which divided the focus ring 3 into the front ring part 3f and the rear ring part 3r was given, the three or more divisions are not excluded. Furthermore, the elastic member 7 can utilize various elastic members other than those illustrated.

  The lens device according to the present invention can be used for various projectors that perform focusing adjustment by rotating a focus ring by a focusing motor.

  DESCRIPTION OF SYMBOLS 1: Lens apparatus, 2: Focusing lens part, 3: Focus ring, 3s: Outer peripheral part of focus ring, 3f: Front ring part, 3r: Rear ring part, 4: Rack part, 5: Focusing motor, 5s: Rotation Shaft, 6: Pinion part, 7: Elastic member, 7e: Elastic member, 8: Lens holder, 9: Pressure adjusting part, Mf: Electric focusing mechanism, P: Projector, Sm: Separating part, Fa: Axial direction, Fr : Radiation direction, Cr: Clearance

Claims (5)

  A pinion portion provided on a rotating shaft of a focusing motor is engaged with a rack portion provided along a circumferential direction of an outer peripheral portion of a focus ring that supports a focusing lens portion, and the focus ring is rotated by operation of the focusing motor. In a projector lens apparatus including an electric focusing mechanism that performs focusing adjustment by moving, a separation unit that mechanically separates the focusing lens unit side and the rack unit side is provided between the focusing lens unit and the rack unit, The projector is characterized in that an elastic member is interposed in the separating portion to couple the focusing lens portion side and the rack portion side so that the focusing lens portion and the rack portion can be relatively elastically displaced. Lens device.   The focus ring is divided into a front ring portion and a rear ring portion, and the compressed elastic member is interposed in the axial direction between the front ring portion and the rear ring portion, and relatively over a predetermined range in the axial direction. The projector according to claim 1, wherein the projector is configured to be elastically displaceable and to be relatively displaceable over a predetermined range by providing a predetermined clearance in a radial direction between the front ring portion and the rear ring portion. Lens device.   The lens holder for supporting the focusing lens portion disposed inside the focus ring and the focus ring are configured separately, and the compressed elastic member is interposed in the axial direction between the focus ring and the lens holder. And is configured to be relatively displaceable over a predetermined range by providing a predetermined clearance in the radial direction between the focus ring and the lens holder. 3. The lens device for a projector according to claim 1, wherein the lens device is a projector.   4. The projector lens device according to claim 1, further comprising a pressure adjusting unit capable of adjusting a magnitude of the pressure applied by the elastic member.   5. The projector lens device according to claim 2, wherein an elastic member is interposed in the clearance.

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