JP2011257530A - Lens shift mechanism and projector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a defect due to the rattling of slide plates.SOLUTION: A first slide plate 32 is attached onto a base plate 30 fixed to a housing of a projector. A second slide plate 34 is attached onto the first slide plate 32. A lens barrel 16 is fixed onto the second slide plate 34. The first slide plate 32 is slidably held in a first direction which is inclined by 45 degrees with respect to a vertical direction and driven by a first slide plate drive mechanism 36, so as to be moved in the first direction. The second slide plate 34 is slidably held in a second direction vertical to the first direction and driven by a second slide plate drive mechanism 38, so as to be moved in the second direction.

Description

  The present invention relates to a lens shift mechanism that slides a lens barrel up and down, left and right, and a projector including such a lens shift mechanism.

  2. Description of the Related Art Projectors including a lens shift mechanism that slides a lens barrel with a built-in projection lens up and down and left and right are widely known. Such a projector includes an upper and lower slide plate that slides up and down, a left and right slide plate that slides left and right, a vertical drive mechanism that moves the vertical slide plate, and a left and right drive mechanism that moves the left and right slide plates.

  By the way, each of the upper, lower, left, and right drive mechanisms includes a cam, a gear, and the like, and a gap called backlash is provided in a connecting portion of the cam and the gear. However, this backlash is necessary for smooth driving, but it also causes backlash. The backlash causes the slide plates on the top, bottom, left and right to shake in the moving direction (the top and bottom slide plates are up and down, and the left and right slide plates are left and right).

  As described above, each of the upper, lower, left and right slide plates has rattling in the moving direction. However, the upper and lower slide plates are urged downward by their own weights, so that no problem occurs even if they rattle. However, since the left and right slide plates cannot be urged by their own weights, it is difficult to finely adjust the position, and problems such as backlash occur due to a slight impact. In particular, when a plurality of projectors are used such as an aircraft simulator and projection images from the projectors are connected to form one image, the problem becomes remarkable.

  In order to prevent such a problem, a method of biasing the left and right slide plates to the left or right by a spring or a magnet can be considered. For example, the following patent document 1 describes a technique for preventing rattling by a magnet, and the following patent document 2 describes a technique that enables adjustment of driving force and position holding force by a spring. ing. By applying these technologies, it is possible to prevent problems caused by rattling of the left and right slide plates.

JP2008-077047 JP 2003-311560 A

  However, when a magnet or a spring is provided, there is a problem that the apparatus is increased in size and cost.

  SUMMARY An advantage of some aspects of the invention is to provide a small-sized and low-cost lens shift mechanism and a projector that can prevent problems caused by rattling.

  In order to achieve the above object, a lens shift mechanism of the present invention is a first slide plate that is attached to a base plate and is slidable along a first slide rail that extends in a first direction parallel to the base plate. A second slide plate attached to the first slide plate and slidably provided along a second slide rail extending in a second direction parallel to the base plate and different from the first direction; A lens barrel fixed to the two slide plates, a first drive mechanism for moving the first slide plate in the first direction, and a second drive mechanism for moving the second slide plate in the second direction. And the first slide plate is urged downward in the first direction by its own weight, and the second slide plate is urged downward in the second direction by its own weight. The first is characterized by tilting the second slide rail with respect to both the horizontal direction.

  It is preferable that the inclination angle of the first slide rail with respect to the horizontal direction is equal to the inclination angle of the second slide rail with respect to the horizontal direction.

  Moreover, it is preferable that both the first and second slide rails are inclined by approximately 45 ° with respect to the horizontal direction.

  Further, the base plate is disposed substantially vertically, the lens barrel moves up and down, left and right within a plane parallel to the base plate, and an operation member operated when moving the lens barrel. And a control means for controlling the first and second drive mechanisms in accordance with an operation instruction input from the operation member, and the control means moves the first slide plate upward in the first direction. At the same time, by moving the second slide plate upward in the second direction by the same distance as the first slide plate, the lens barrel is moved upward, and the first slide plate is moved to the first slide plate. And moving the lens barrel downward by moving the second slide plate downward in the second direction by the same distance as the first slide plate. And moving the first slide plate upward in the first direction and moving the second slide plate downward in the second direction by the same distance as the first slide plate. , Moving the lens barrel to one of the left and right, moving the first slide plate downward in the first direction, and moving the second slide plate by the same distance as the first slide plate. It is preferable to move the lens barrel to the other of the left and right by moving it upward in the two directions.

  In addition, a projector according to the present invention includes the lens shift mechanism as described above.

  According to the present invention, since both the first and second slide plates can be urged by gravity, it is possible to prevent problems due to rattling. In addition, according to the present invention, it is possible to prevent problems due to rattling regardless of springs or magnets, so that downsizing and cost reduction are possible.

It is a front view of a projector. It is a front view of a lens shift mechanism. It is explanatory drawing which shows a mode that the 1st slide board is hold | maintained slidably. It is explanatory drawing which shows a mode that the 2nd slide board is hold | maintained slidably. It is an enlarged view of a 1st slide board drive mechanism. It is an enlarged view of a 2nd slide board drive mechanism. It is a block diagram which shows the structure of the mechanism which drive-controls a 1st, 2nd motor. It is a flowchart which shows the procedure which drive-controls a 1st, 2nd motor.

  As shown in FIG. 1, the projector 10 includes a housing 12 having a substantially rectangular parallelepiped shape, and a lens barrel 16 including a projection lens 14 is exposed from the front surface of the housing 12. The housing 12 is provided with a light source, an image generation optical system, and the like. The projector 10 converts illumination light from the light source into image light through the image generation optical system, and this image light is a projection lens. 14 on the screen.

  Further, the projector 10 includes a lens shift mechanism 20 for sliding the lens barrel 16 up and down, left and right, and an upper button 22 a that is operated when the lens barrel 16 is moved on the front surface of the housing 12. , A lower button 22b, a right button 22c, and a left button 22d are provided. The lens barrel 16 moves upward when the upper button 22a is operated, moves downward when the lower button 22b is operated, moves right when the right button 22c is operated, and moves left when the left button 22d is operated. To do.

  As shown in FIG. 2, the lens shift mechanism 20 includes a base plate 30, a first slide plate 32, a second slide plate 34, a first slide plate drive mechanism 36, and a second slide plate drive mechanism 38. Composed. The base plate 30 is fixed to the housing 12. A first slide plate 32 is attached to the front surface of the base plate 30, a second slide plate 34 is attached to the front surface of the first slide plate 32, and a lens barrel 16 is attached to the front surface of the second slide plate 34. Fixed.

  As shown in FIG. 3, two parallel slide rails 30a and 30b are provided on the front surface of the base plate 30, and the first slide plate 32 is attached to the slide rails 30a and 30b. The slide rails 30a and 30b are arranged in a state parallel to the base plate 30 and inclined by 45 ° with respect to the horizontal direction so as to extend from the upper right to the lower left, and the first slide plate 32 is disposed on the slide rails 30a and 30b. (Hereinafter, the moving direction of the first slide plate 32, that is, the longitudinal direction of the slide rails 30a and 30b is referred to as a first direction).

  As shown in FIG. 4, two parallel slide rails 32a and 32b are provided on the front surface of the first slide plate 32, and the second slide plate 34 is attached to the slide rails 32a and 32b. The slide rails 32a and 32b are provided perpendicular to the first direction, and the second slide plate 34 is slidably held along the slide rails 32a and 32b (hereinafter, the moving direction of the second slide plate 34). That is, the longitudinal direction of the slide rails 32a and 32b is referred to as a second direction).

  As shown in FIGS. 2, 3, and 4, the base plate 30 is provided with an opening 40, the first slide plate 32 is provided with an opening 42, and the second slide plate 34 is provided with an opening 44. . These openings 40, 42, 44 are provided to open the optical path of the image light to be projected, and the image light is moved even if the lens barrel 16 moves as the first slide plate 32 or the second slide plate 34 slides. The size, position, and shape are determined so as not to block the optical path. Further, the first slide plate 32 is provided with a first groove portion 46 connected to the first slide plate drive mechanism 36, and the second slide plate 34 is connected to the second slide plate drive mechanism 38. A groove 48 is provided.

  As shown in FIG. 5, the first slide plate drive mechanism 36 includes a first motor 50, a first rotating shaft 52, and a first moving piece 54. Each part of the first slide plate drive mechanism 36 is attached to the front surface of the base plate 30. The first motor 50 is a stepping motor and includes a first drive shaft 56 that is orthogonal to the first rotation shaft 52. The first motor 50 rotates the first drive shaft 56 by an amount corresponding to the number of drive pulses supplied from a motor control unit 70 described later.

  The first rotating shaft 52 is disposed in parallel with the first direction. The first rotary shaft 52 and the first drive shaft 56 are constituted by a first worm gear 58 including a first worm 58 a provided on the first drive shaft 56 and a first worm wheel 58 b provided on the first rotary shaft 52. When the first motor 50 rotates, this rotational force is transmitted to the first rotating shaft 52 via the first worm gear 58 and the first rotating shaft 52 rotates. Further, the first rotating shaft 52 is provided with a first screw portion 52a formed with a thread, and the first moving piece 54 is screwed to the first screw portion 52a.

  The first moving piece 54 includes a first engagement protrusion 54 a, and the first engagement protrusion 54 a is engaged with a first groove portion 46 formed on the first slide plate 32. Further, the first moving piece 54 has a back surface in contact with the front surface of the base plate 30, and rotation about the first rotation shaft 52 is restricted. Accordingly, when the first rotation shaft 52 rotates, the first slide plate 32 slides in the first direction together with the first moving piece 54. Thus, the rotational force of the first motor 50 is transmitted to the first slide plate via the first rotating shaft 52 and the first moving piece 54, and the first slide plate 32 moves. In the present embodiment, the first slide plate 32 moves to the upper right when the first motor 50 rotates forward, and the first slide plate 32 moves to the lower left when the first motor 50 rotates backward. Give an explanation.

  As shown in FIG. 6, the second slide plate drive mechanism 38 includes a second motor 60, a second rotating shaft 62, and a second moving piece 64. Each part of the second slide plate drive mechanism 38 is attached to the front surface of the base plate 30. The second motor 60 is a stepping motor and includes a second drive shaft 66 that is orthogonal to the second rotation shaft 62. The second motor 60 rotates the second drive shaft 66 by an amount corresponding to the number of drive pulses supplied from a motor control unit 70 described later.

  The second rotating shaft 62 is disposed in parallel with the second direction. The second rotary shaft 62 and the second drive shaft 66 are constituted by a second worm gear 66 comprising a second worm 66 a provided on the second drive shaft 66 and a second worm wheel 66 b provided on the second rotary shaft 62. When the second motor 60 rotates, this rotational force is transmitted to the second rotating shaft 62 via the second worm gear 66 and the second rotating shaft 62 rotates. Further, the second rotating shaft 62 is provided with a second screw portion 62a formed with a thread, and the second moving piece 64 is screwed to the second screw portion 62a.

  The second moving piece 64 includes a second engagement protrusion 64 a, and the second engagement protrusion 64 a is engaged with a second groove portion 48 formed on the second slide plate 34. The second slide plate 34 also slides in the first direction as the first slide plate 32 slides. Therefore, even if the second slide plate 34 slides in the first direction, the second engagement protrusion 64a and the second slide plate 34 are moved. The second engaging protrusion 64a and the second groove 48 are formed long in the first direction so that the engagement with the two grooves 48 is maintained.

  Further, the second moving piece 64 has a back surface in contact with the front surface of the base plate 30 and is restricted from rotating around the second rotation shaft 62. Accordingly, when the second rotation shaft 62 rotates, the second slide plate 34 slides in the second direction together with the second moving piece 64. Thus, the rotational force of the second motor 60 is transmitted to the second slide plate 34 via the second rotating shaft 62 and the second moving piece 64, and the second slide plate 34 moves. In the present embodiment, the second slide plate 34 moves to the upper left when the second motor 60 rotates forward, and the second slide plate 34 moves to the lower right when the second motor 60 rotates backward. We will explain in.

  As shown in FIG. 7, the first motor 50 that moves the first slide plate 32 and the second motor 60 that moves the second slide plate 34 are both connected to the motor control unit 70, and this motor control unit 70. It is driven and controlled by. The motor control unit 70 is connected to the above-described upper, lower, left, and right buttons 22a to 22d. The motor control unit 70 receives the first and second motors based on the operation signals input from the buttons 22a to 22d. The lens barrel 16 is moved up, down, left, and right by driving and controlling 50 and 60.

  Specifically, as shown in FIG. 8, when the upper button 22a is operated, the first and second motors 50 and 60 are rotated forward by the same amount, and the first slide plate 32 is moved to the upper right and the second slide plate. The lens barrel 16 is moved upward by moving each of 34 to the upper left. Further, when the lower button 22b is operated, the first and second motors 50 and 60 are reversely rotated by the same amount to move the first slide plate 32 to the lower left and the second slide plate 34 to the lower right. The lens barrel 16 is moved downward.

  Further, when the right button 22c is operated, the first motor 50 is rotated forward to move the first slide plate 32 toward the upper right, and the second motor 60 is rotated backward by the same amount as the first motor 50. By moving the second slide plate 34 toward the lower right, the lens barrel 16 is moved to the right. When the left button 22d is operated, the first motor 50 is rotated in the reverse direction to move the first slide plate 32 to the lower left, and the second motor 60 is rotated in the reverse direction by the same amount as the first motor 50. By moving the second slide plate 34 to the upper left, the lens barrel 16 is moved to the left.

  In the projector 10, the first slide plate 32 rattles in the first direction due to the backlash of the “worm gear” and “screw part and moving piece”, the gap between the “engagement protrusion and groove part”, and the second slide. The plate 34 rattles in the second direction. However, the moving directions (first and second directions) of the first and second slide plates 32 and 34 are both inclined by 45 ° with respect to the horizontal direction, and the first and second slide plates 32 and 34 are both Due to its own weight, the first slide plate 32 is biased downward in the first direction (lower left) and the second slide plate 34 is biased downward in the second direction (lower right). For this reason, the malfunction by rattling can be prevented.

  In the present invention, both the first and second slide plates may be inclined with respect to the horizontal direction so that both the first and second slide plates are urged in the movement direction by their own weight. The detailed configuration is not limited to the above embodiment and can be changed as appropriate.

  For example, in the above embodiment, the example in which the moving directions of the first and second slide plates are both inclined by 45 ° with respect to the horizontal direction has been described. However, the moving directions of the first and second slide plates are both set to the horizontal direction. Tilt the moving direction of the first and second slide plates to be larger or smaller than 45 °, such as tilting 30 ° or moving the first and second slide plates 60 ° with respect to the horizontal direction. Also good. In the above-described embodiment, the example in which the inclination angles of the moving directions of the first and second slide plates with respect to the horizontal direction are the same is described. For example, the moving direction of the first slide plate is inclined by 30 ° with respect to the horizontal direction. The inclination of the movement direction with respect to the horizontal direction may be different between the first slide plate and the second slide plate, such that the movement direction of the second slide plate is inclined by 60 ° with respect to the horizontal direction. Thus, the inclination of the moving direction of the first and second slide plates can be freely set as long as both the first and second slide plates are urged in the moving direction by their own weight.

  In the above embodiment, the example in which the first slide plate is disposed on the base plate and the second slide plate is disposed on the first slide plate has been described. However, the first slide plate is disposed on one side of the base plate. And the second slide plate may be disposed on a surface opposite to the one surface of the base plate.

  Furthermore, in the said embodiment, although the 1st slide plate drive mechanism was demonstrated in the example attached to the base plate, you may attach a 1st slide plate drive mechanism to a 1st slide plate or a 2nd slide plate. Similarly, in the above embodiment, the example in which the second slide plate driving mechanism is attached to the base plate has been described. However, the second slide plate drive mechanism may be attached to the second slide plate or the first slide plate. .

  In the above-described embodiment, an example in which four buttons, upper, lower, left, and right are provided as operation members operated when moving the lens barrel, but the present invention is not limited to this. For example, two operation members, a vertical operation lever for moving the lens barrel up and down for moving the lens barrel and a left and right operation lever for moving the lens barrel to the left and right, are provided. The lens barrel may be moved in response to the operation. Further, the lens barrel may be moved in response to the operation of one operation member such as a cross key or a stick-like operation member.

  Furthermore, in the above-described embodiment, the example in which the lens barrel is moved in the four directions, up, down, left, and right in response to the operation of the operation member has been described, but the present invention is not limited to this. According to the present invention, by adjusting the amount of movement of the first and second slide plates (by controlling the amount and direction of rotation of the first and second motors), the lens is in a plane parallel to the base plate. Since the lens barrel can be moved in any direction, for example, when the cross key or stick-shaped operating member is operated in an oblique direction, when the up / down operation lever and the left / right operation lever are operated simultaneously, The lens barrel may be moved in an oblique direction when the button and the left and right buttons are operated simultaneously.

  In the above embodiment, the base plate is disposed so that the front surface of the base plate faces the front of the projector, that is, the base plate is disposed substantially vertically. However, the present invention is not limited to this. is not. If the first and second slide plates are both within the range in which the first and second slide plates are urged in the moving direction by their own weight, the base plate may be disposed tilted forward or rearward.

  In the above embodiment, the example in which the present invention is applied to the lens shift mechanism of the projector has been described. However, the present invention may be applied to a lens shift mechanism of an optical device other than the projector.

DESCRIPTION OF SYMBOLS 10 Projector 14 Projection lens 16 Lens barrel 20 Lens shift mechanism 22a Up button 22b Down button 22c Right button 22d Left button 30 Base plate 32 1st slide plate 34 2nd slide plate 36 1st slide plate drive mechanism 38 2nd slide plate Drive mechanism 50 First motor 60 Second motor 70 Motor controller

Claims (5)

A first slide plate attached to the base plate and slidably provided along a first slide rail extending in a first direction parallel to the base plate;
A second slide plate attached to the first slide plate and slidable along a second slide rail extending in a second direction parallel to the base plate and different from the first direction;
A lens barrel fixed to the second slide plate;
A first drive mechanism for moving the first slide plate in the first direction;
A second drive mechanism for moving the second slide plate in the second direction,
The first slide plate is urged downward in the first direction by its own weight, and the first slide plate is urged downward in the second direction by its own weight. A lens shift mechanism characterized in that both of the second slide rails are inclined with respect to the horizontal direction.   2. The lens shift mechanism according to claim 1, wherein an inclination angle of the first slide rail with respect to the horizontal direction is equal to an inclination angle of the second slide rail with respect to the horizontal direction.   3. The lens shift mechanism according to claim 2, wherein both the first and second slide rails are inclined by approximately 45 degrees with respect to the horizontal direction. The base plate is disposed substantially vertically,
The lens barrel moves vertically and horizontally within a plane parallel to the base plate,
An operation member that is operated when moving the lens barrel;
Control means for controlling the first and second drive mechanisms according to an operation instruction input from the operation member;
The control means includes
The lens is moved by moving the first slide plate upward in the first direction and moving the second slide plate upward in the second direction by the same distance as the first slide plate. Move the lens barrel upward,
By moving the first slide plate downward in the first direction and moving the second slide plate downward in the second direction by the same distance as the first slide plate, Move the lens barrel downward,
The first slide plate is moved upward in the first direction, and the second slide plate is moved downward in the second direction by the same distance as the first slide plate. Move the lens barrel to the left or right,
By moving the first slide plate downward in the first direction and moving the second slide plate upward in the second direction by the same distance as the first slide plate, 4. The lens shift mechanism according to claim 2, wherein the lens barrel is moved to the left and right other.   A projector comprising the lens shift mechanism according to claim 1.

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