JP2003005279A - Tilt device for projector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable a user to easily perform horizontal adjustment and elevation angle adjustment while viewing a projected picture. SOLUTION: The tilt device is provided with one expansible leg 1 consisting of a leg support part 3 which is provided with a rack gear 3a on a side face and is provided with an earth part 3b in the lower end and a guide 2 which movably houses the leg support part 3 and is suspended in a projector main body 10; a rotation driving force transmission part 7 consisting of a first transmission part 5 which is provided with a pinion gear 5a engaged with the rack gear 3a and a worm wheel 5b which connects to a shaft 5c of the pinion gear 5a and is engaged with a worm gear 6a and a second transmission part 6 which is provided with the worm gear 6a and a transmission gear 6b which is provided to a shaft 6c of the worm gear 6a successively; a driving motor 8 which is provided to the shaft of the second transmission part successively, a reception processing part 9a which receives an indication signal to take out an indication instruction; and a control part 9 which controls the driving motor 8, the rotation driving force transmission part 7 and the reception processing part 9a.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tilt device for a projector, which can easily perform tilt adjustment and the like for adjusting a projection angle.

[0002]

2. Description of the Related Art FIG. 4 is an image diagram for explaining a situation in which a liquid crystal projector magnifies and projects a projected image on a screen. An overall view showing a state of the projected image and an enlarged view showing expansion and contraction of legs of the liquid crystal projector. is there. As shown in the overall view of FIG. 4, when the image display device, for example, the projector main body 10 magnifies and projects the projected image on the screen, the horizontal direction of the projected image does not match the horizontal direction of the screen and is inclined. Alternatively, the projection image may be displayed in an unsightly state such as being displayed near the edge of the screen. Therefore, as shown in the enlarged view of FIG. 4, the projector main body 10 has a height adjustment function so that horizontal adjustment for adjusting the tilt of the liquid crystal projector in the left-right direction and tilt adjustment for adjusting the tilt in the front-rear direction can be performed. The telescopic feet are provided, and the telescopic feet are directly rotated for expansion and contraction for each telescopic foot to adjust the height, thereby performing horizontal adjustment and elevation adjustment.

However, for adjusting the height of each telescopic foot, for example, a method of rotating a screw type telescopic foot provided at the four corners of the bottom surface of the projector body 10 is adopted.
In the projected state, it is difficult to put a finger between the bottom surface of the projector main body 10 and the stand, and it is difficult to rotate the telescopic foot, so that adjustment is difficult. Therefore, conventionally, the power of the projector main body 10 is turned off, and the projector main body 10 in the non-operating state is adjusted, for example, with the side face down and the telescopic legs are rotated to make an extension with a register. .

In the above-described conventional horizontal adjustment and elevation angle adjustment methods, since the telescopic foot is rotated in the non-operating state, the telescopic work is easy, but the projected image during the adjustment cannot be seen, and the degree of the adjustment is difficult to understand. After all, there was a problem that adjustment required skill, and adjustment took time and effort.

By the way, Japanese Patent Laid-Open No. 2000-241875 has been disclosed as a technique for automatically performing the above-mentioned tilt adjustment in an operating state. This technique is a technique relating to tilt adjustment within the maximum movable range of the telescopic foot, and There has been a problem that the technique relating to the actual tilt adjustment including the limit operation of the movable range is not mentioned.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object of the present invention is to provide a tilting device for a projector, which can easily perform horizontal adjustment and elevation adjustment while viewing a projected image.

[0007]

In order to solve the above problems, the present invention has the following means.

A tilting device for a projector in which telescopic feet are hung vertically on a main body, and a rod-shaped foot support portion having a rack gear on a side surface and a grounding portion at a lower end, and the foot support portion are movably accommodated. A first transmission portion including a telescopic foot that is a guide vertically installed on the projector body, a pinion gear that is screwed to the rack gear, and a worm wheel that is connected to a shaft of the pinion gear and that is screwed to a worm gear, and the worm gear. A rotary driving force transmission part including a second transmission part provided with a transmission gear that is connected to the shaft of the worm gear and that changes the rotation speed, and a drive motor that is connected to the shaft of the second transmission part.
A reception processing unit that receives a sensing signal and an instruction signal for operating the tilting device, decodes the signal, and extracts an instruction command, and a control unit that controls the drive motor, the rotational driving force transmission unit, and the reception processing unit. And a pressing piece protruding near the upper end of the foot supporting portion, and two pressing pieces corresponding to the upper and lower ends of the range of movement of the foot supporting portion at the upper and lower ends of the telescopic foot guide. An upper limit switch and a lower limit switch are provided so as to correspond to one position, and the control unit controls on / off of the drive motor according to a signal detected and output by the upper limit switch or the lower limit switch.

Further, a shaft of the pinion gear of the first transmission portion is extended, a second pinion gear is provided at the other end of the shaft, and a foot support portion provided with a rack gear screwed to the second pinion gear is provided. A second telescopic foot is provided which serves as a guide for movably storing the foot support portion.

Further, the drive motor is a variable speed motor and is driven by changing the rotational speed of the pinion gear under the control of the control section.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION A tilt device for a projector according to the present invention will be described in detail below with reference to the drawings. Figure 1
FIG. 3A is a perspective view showing an essential part of a projector tilting device according to an embodiment of the present invention, and FIG.

As shown in FIG. 1, the present invention is a tilting device for a projector in which a telescopic foot 1 is vertically installed inside a main body 10 at the front center. A rod-shaped foot support section 3 having a rack gear 3a on the side surface and a non-slip member at the lower end, for example, a grounding section 3b made of a rubber material, and the foot support section 3 are housed so as to be movable in the vertical direction, and the projector main body 10 One telescopic foot 1 consisting of a guide 2 hung vertically in the front center of the inside, a pinion gear 5a screwed to the rack gear 3a, and a shaft 5c of the pinion gear 5a, which are continuously connected to a worm gear 6a. The first transmission portion 5 having a worm wheel 5b, the worm gear 6a, and a shaft 6c of the worm gear 6a are connected to each other, and are rotated by a plurality of gears (not shown) so that the extension / contraction speed of the extension / contraction foot 1 is suitable for tilt adjustment. Second transmission unit 6 including a transmission gear 6b configured to change the number
A rotational driving force transmission unit 7, a drive motor 8 connected to the shaft of the second transmission unit 6, and a reception processing unit 9a that receives an instruction signal and decodes the instruction signal to extract an instruction command.
The controller 9 is provided with a control signal for inputting a sensing signal for operating the tilting device and controlling the drive motor 8, the rotational driving force transmission portion 7 and the reception processing portion 9a.

Further, a pressing piece 4c is provided near the upper end of the foot supporting portion 3 and the pressing piece corresponding to the upper and lower ends of the upper and lower ends of the guide 2 in which the foot supporting portion 3 moves. Corresponding to the two positions of 4c,
An upper limit switch 4a and a lower limit switch 4b are provided so as to contact the pressing piece 4c.

The operation of the above arrangement will be described below. When the drive motor 8 is controlled to rotate in the normal direction, for example, based on an instruction from the control unit 9, the drive force of the normal rotation decreases the rotation speed at a fixed ratio via the transmission gear 6b of the second transmission unit 6. Worm gear 6a
To rotate. Therefore, the driving force is transmitted to the worm wheel 5b screwed to the worm gear 6a, and the worm wheel 5b rotates in a predetermined direction at a rotation speed corresponding to the gear ratio of the worm gear 6a and the worm wheel 5b. Therefore, the pinion gear 5a connected to the shaft 5c of the worm wheel 5b of the first transmission portion 5 rotates in the same direction as the worm wheel 5b, and the driving force of the pinion gear 5a is screwed onto the pinion gear 5a. It is transmitted to the rack gear 3a that is in motion, and as a result, the rack gear 3a is moved in the linear direction. Therefore, the foot support portion 3 having the rack gear 3a on its side surface moves downward in the guide 2 vertically installed inside the projector body 10, so that the foot support portion 3 extends below the projector body 10. Due to the extension action of the telescopic foot 1, the projector body 10 is supported by the telescopic foot 1 by the reaction and lifted up.

Conversely, when the drive motor 8 is rotated in the reverse direction, the obtained rotational force is transmitted to the rack gear 3a via the second transmission portion 6 and the first transmission portion 5 in the same manner as described above, and the foot support is carried out. As a result of the movement of the portion 3 upward, the foot support portion 3 contracts so as to be housed inside the projector main body 10, and due to the contracting action of the elastic foot 1, the projector main body 10 is expanded and contracted.
It descends while being supported by. The worm gear 6a allows the telescopic foot 1 to retain its current position even if the drive motor 8 is stopped midway.
The position (projection range) of is fixed.

In practice, the drive motor 8 may be rotated in the forward direction for a long time. First, when the foot support portion 3 is completely housed in the guide 2, the upper limit switch 4a is moved to the foot support portion. It contacts the pressing piece 4c protruding near the upper end of 3 and is turned on, for example. Control unit 9
Receives this switch-on signal and stops the drive motor 8. By the stopping operation at the upper limit position, seizure of the motor and damage to the gear can be reliably prevented. In the case of reverse rotation, secondly, when the foot support 3 is completely out of the guide 2, the lower limit switch 4b is actuated to stop the drive motor 8 at the lower limit position. As a result, the foot support portion 3 can be prevented from slipping off the guide 2, and seizure of the motor and damage to the gear can be reliably prevented as in the case of normal rotation.

Further, if the reception processing section 9a is composed of, for example, an infrared remote control reception section, tilt (elevation angle) adjustment can be easily performed. In particular, if the light receiving window 9b of the remote control receiver is provided on the rear surface of the projector main body 10, the operator can make adjustments from the rear of the projector main body 10 while looking at the projection screen almost in front, so that accurate adjustments are facilitated. it can.

FIG. 2 is an image view showing the second and third embodiments of the tilt device for a projector according to the present invention. The plan view (a) and side view (b) of the second embodiment and the third embodiment are shown. FIG. 4 is a plan view (C) and a front view (D) of FIG. As shown in the figure (a), support the projector main body 10 with three legs,
The one provided at the front center is realized by the telescopic foot 1 according to the present invention. As shown in FIG.
Is an embodiment in which tilt (elevation angle) adjustment that adjusts tilt in the front-back direction can be performed.

Further, as shown in FIG. 2C, it is also effective to support the projector main body 10 with three legs and adopt the telescopic legs 1 according to the present invention to the front two. In this example, as shown in the front view of FIG. 4D, by operating the two telescopic feet 1 separately, not only the tilt (elevation angle) adjustment of the projector body 10 but also the tilt adjustment in the horizontal direction can be performed. . It should be noted that the fixed foot is shown in FIG. 2C as one, but it may be two.

FIG. 3 is an image diagram showing a fourth embodiment of the tilt device of the projector according to the present invention. The same parts as those in FIG. 1 are designated by the same reference numerals, and the duplicated description will be omitted. The shaft 5c of the pinion gear 5a of the first transmission portion 5 is extended, and the second pinion gear 5d is provided at the other end of the shaft 5c.
The second rack gear 3c screwed to the second pinion gear 5d.
Second telescopic foot 1 including a second foot support portion 30 including a second foot support portion 30 and a second guide 20 that movably accommodates the second foot support portion 30.
1 was set.

In the above example, one worm wheel 5b
Drives the pinion gear 5a and the second pinion gear 5d provided at both ends of the shaft 5c, and the rotational force of each pinion gear linearly drives the corresponding rack gear 3a and the second rack gear 3c. Since the movement with the second telescopic foot 11 is synchronized and expands and contracts in conjunction with each other, there is no inclination in the left-right direction, and the tilt (elevation angle) adjustment for adjusting the inclination in the front-back direction can be easily performed.

Although not shown, for example, in FIG.
When the telescopic foot 1 and the second telescopic foot 11 of the tilt device of the projector are hooked and fixed to the ceiling suspension metal plate of the ceiling and used in a suspended state, the telescopic foot 1 and the second telescopic foot 11 are telescopically extended. By doing so, the tilt (elevation angle) can be easily adjusted.

When the drive motor 8 is a variable speed motor and is configured to be driven by changing the rotation speed of the pinion gear 5a under the control of the control unit 9, for example, the drive motor 8 in tilt (elevation angle) adjustment. If the control is performed such that the rotation speed is roughly adjusted as a high speed rotation and then the rotation speed is slowly adjusted as a fine adjustment, the ease of the actual adjustment work can be improved.

[0024]

As described above, the present invention is a tilting device for a projector which can be used for both a stationary type and a ceiling type which can easily adjust the horizontal level and the elevation angle while viewing the projected image. In particular, while the related art discloses a technique related to general tilt adjustment, the present invention relates to the entire technique including the limit position of the maximum movable range of the telescopic foot, and even in the operation at the limit position. , A technique for preventing deterioration and damage of a drive motor is provided.

[Brief description of drawings]

FIG. 1 is an image diagram and a magnified view of a main part of a tilting device of a projector according to an embodiment of the present invention.

2A and 2B are image diagrams showing second and third embodiments of a tilt device for a projector according to the present invention, including a plan view (A) and a side view (B) of the second embodiment, and a plan view of the third embodiment. It is (c) and a front view (d).

FIG. 3 is an image diagram showing a fourth embodiment of the tilt device of the projector according to the present invention.

FIG. 4 is an image diagram for explaining a situation in which a liquid crystal projector enlarges and projects a projection image on a screen, and is an overall view showing a state of the projection image and an enlarged view showing expansion and contraction of legs of the liquid crystal projector.

[Explanation of symbols]

1 telescopic foot 2 guides 3 foot support 3a rack gear 3b Grounding part 3c Second rack gear 4a Upper limit switch 4b Lower limit switch 4c pressing piece 5 First transmission part 5a pinion gear 5b worm wheel 5c axis 5d Second pinion gear 6 Second transmission part 6a Worm gear 6b speed change gear 6c axis 7 Rotational driving force transmission section 8 drive motor 9 control unit 9a Reception processing unit 9b Light receiving window 10 Projector body 11 Second telescopic foot 20 Second Guide 30 Second foot support

Claims (3)

[Claims] 1. A tilting device for a projector, comprising telescopic feet extending vertically from a main body, wherein a rod-shaped foot support portion having a rack gear on a side surface and a grounding portion at a lower end, and the foot support portion are movably accommodated. And a first transmission portion including a telescopic foot that is a guide vertically installed on the projector body, a pinion gear that is screwed to the rack gear, and a worm wheel that is connected to a shaft of the pinion gear and that is screwed to a worm gear. A rotation driving force transmission unit including a worm gear and a second transmission unit that is connected to the shaft of the worm gear and that has a speed change gear that changes the rotation speed, a drive motor that is connected to the shaft of the second transmission unit, and an instruction signal. A reception processing unit for receiving the above-mentioned signal and decoding the same signal to obtain an instruction command, and for inputting a sensing signal for operating the tilting device and for inputting the drive motor and the rotational driving force transmission unit, And a control unit for controlling the signal processing unit, a pressing piece is provided in the vicinity of the upper end of the foot support unit, and the upper and lower ends of the upper and lower ends of the telescopic foot guide in the range in which the foot support unit moves. The upper limit switch and the lower limit switch are provided so as to correspond to the two positions of the pressing piece corresponding to, and the control unit drives the drive motor in response to a signal detected by the upper limit switch or the lower limit switch and output. A tilt device for a projector, which is controlled to be turned on and off. 2. A foot support portion including a rack gear that extends a shaft of a pinion gear of the first transmission portion, provides a second pinion gear at the other end of the shaft, and has a rack gear that is screwed to the second pinion gear. 2. The tilting device for a projector according to claim 1, further comprising a second telescopic foot that serves as a guide for movably housing the foot support portion. 3. The tilt device for a projector according to claim 1, wherein the drive motor is a variable speed motor, and the pinion gear is driven by changing the rotation speed thereof under the control of the control unit.