JP3682292B2 - Projector shading device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a projector light shielding device.
[0002]
[Prior art]
When one explainer explains to many people, such as a school lesson or a company presentation, the explainer may explain the image projected on the screen by a projector with a stick or the like. .
In this case, for the convenience of explaining by the side of the screen, the presenter must always explain in a situation where the presenter is exposed to the light source irradiated from the lens of the projector. However, the description may be made without referring to the screen image or the like. In this case, an image is not projected on the screen and the light from the light source is projected directly, but the light at this time (light when the image is not projected on the screen) is particularly dazzling to protect the vision from the presenter. Requested that the light source be cut off. In contrast, conventionally, measures such as turning off the power of the projector itself have been taken.
[0003]
[Problems to be solved by the invention]
However, once the projector is turned off, it will take some time after the power is turned on even if the projector is turned on again so that the projector can be used. There was a problem of becoming. Therefore, measures such as attaching a member that covers the light source of the projector have been studied. In this case, in the projector including the casing, a ventilation fan vent is set along with the light projecting lens. In some cases, however, if the externally attached member blocks the ventilation opening, the cooling function of the projector may be impaired.
The present invention has been completed on the basis of the above circumstances, and while maintaining the cooling function provided in the projector, the light source irradiated from the light projecting portion of the projector is cut off to allow the presenter's vision to be viewed. An object of the present invention is to provide a projector shading device that can be protected.
[0004]
[Means for Solving the Problems]
As means for achieving the above-mentioned object, the invention of claim 1 is characterized in that a shielding member formed so as to shield a light projecting portion provided on a side surface of a projector provided with a casing, and the light shielding member as the light projecting member. A projector light-shielding device comprising: a drive unit that is positioned in front of the projector and displaces between a blocking position that blocks the light projecting unit and an open position that opens the light projecting unit; and a mounting unit that can be attached to the projector an apparatus, in what the casing to vent for the cooling fan on the side the light projecting unit is arranged with a cooling fan for cooling the inside of the casing to the interior is provided is provided, said drive means Provides a rotating shaft for rotating the shielding member about the axis thereof in a direction along the side surface on which the light projecting portion is provided, and the light projecting portion is opened and closed by the rotating operation of the shielding member. Characterized with, the mounting portion, said shielding member where provided with a position adjustable slide mechanism manually the arrangement of the shielding member in the same side surface by sliding along the side of the light projecting portion is provided performed Have
[0007]
According to a second aspect of the present invention, in the one according to the first aspect, the side surface of the shielding member facing the light projecting portion is configured to suppress reflection of the light irradiated from the light projecting portion on the shielding member. It is characterized in that a simple reflection suppressing means is applied.
[0009]
[Action and effect of the invention]
<Invention of Claim 1>
According to the first aspect of the invention, since the shielding member is configured to open and close the light projecting unit, it is possible to block light from the light projecting unit and protect the vision of the presenter. Further, since the shielding member operates in a region avoiding the ventilation opening, the ventilation opening is not blocked even when the shielding member is in the blocking position or the opening position. Accordingly, ventilation is normally performed when the projector is used, and no hot air is trapped in the casing.
[0010]
According to the first aspect of the present invention, the position of the shielding member can be adjusted by the slide mechanism after the attachment to the projector is completed. Can also be used.
Further, in a small projector, if a light projecting portion and a ventilation opening are provided on the side surface of the casing, the remaining space on the side surface is narrow, so that the opening position cannot be set avoiding the ventilation opening. In this case, an open position is set outside the casing. However, if the moving mode of the shielding member is a slide type, it is necessary to provide a guide for sliding the shielding member outside the casing. For this reason, when a slide type projector is applied to this type of projector, the projector shading device is increased in size, and the guide portion protrudes from the outer shape of the projector in the attached state. According to the first aspect of the present invention, the moving form of the shielding member is a rotating type, and the shielding member is fixed to the rotating shaft and rotationally displaced about the axis. Therefore, even if the open position is set outside the casing, the shielding member can be opened and closed without providing a guide outside the casing. It will be compact without jumping out from.
[0011]
<Invention of Claim 2>
Considering the manufacturing error of the projector and the projector shading device, and the operational error of the shielding member, in order to avoid the shielding member from interfering with the light projecting part at the shielding position, It is necessary to set a gap for avoiding interference between them. However, if this gap is widened, there is a possibility that light irradiated from the light projecting part and reflected from the surface of the shielding member may leak from the gap. According to the second aspect of the present invention, the reflection suppressing means can suppress the reflection on the shielding member, so that the strong reflected light does not leak from the gap.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
<First Embodiment>
A first embodiment of the present invention will be described with reference to FIGS.
FIG. 1 shows a projector shading device (hereinafter simply referred to as a shading device) 10 applied to the first embodiment. Reference numeral 1 denotes a liquid crystal projector to which the shading device 10 is attached. The liquid crystal projector 1 has a casing 2 having a substantially box shape, and support legs 5 are provided at the four corners of the lower surface thereof, which can be used by being placed on a table or suspended from a ceiling (in this embodiment). Use suspended from the ceiling). The left side of the front wall 3 of the casing 2 is provided with a light projecting portion 4 composed of a cylindrical lens cover 4A and a light projecting lens 4B, and an image is displayed on the screen via the light projecting lens 4B. The projection is enlarged. The liquid crystal projector 1 is provided with a cooling fan (not shown) for cooling the inside of the casing 2, and the front wall 3 is provided with a ventilation fan 6 along with the light projecting unit 4. ing. Thereby, air is circulated so that hot air is not trapped in the casing 2.
[0014]
Next, the light shielding device 10 will be described.
The mounting portion 11 for the liquid crystal projector 1 includes a connecting bracket 12 including an upper bracket 13 formed by bending a metal plate, a lower bracket 15 and an intermediate bracket 14 that joins both the upper and lower brackets 13 and 15 together. Become. A substrate portion 13A of the upper bracket 13 and a substrate portion 15A of the lower bracket 15 serve as attachment surfaces for the ceiling and the upper surface of the liquid crystal projector 1, respectively. On the other hand, fixtures (not shown) are also provided on the ceiling side and the upper surface side of the liquid crystal projector 1, respectively, and the upper bracket 13 is connected to the ceiling side, and the lower bracket 15 is connected to the upper surface of the liquid crystal projector 1. It has come to be.
[0015]
A front wall 15B bent at a right angle is provided on the front side of the lower bracket 15. The front wall 15B is formed along the width direction of the liquid crystal projector 1, and a light shielding device main body 20 to be described later is attached to the front wall 15B via a slide mechanism 17. The slide mechanism 17 includes a pair of fixed rails 17A and a movable rail 17B that extend along the width direction of the liquid crystal projector 1. Among these, the left and right sides of the fixed rail 17A are screwed to the front wall 15B, while the light shielding device main body 20 is attached to the side surface of the movable rail 17B via an L-shaped front bracket 18. The slide mechanism 17 is of a manual type, and is configured to slide the movable rail 17B and eventually the light shielding device main body 20 along the fixed rail 17A. The slide mechanism 17 is provided in this manner because the arrangement of the light projecting unit 4 on the front wall 3 differs depending on the model of the liquid crystal projector 1, and a closing position described later is set in accordance with the light projecting unit 4 of the model. This is necessary.
[0016]
The light-shielding device main body 20 has a shielding plate (corresponding to a shielding member of the present invention) 21 and a support case 25 to which the shielding plate 21 is attached, and driving means for rotationally displacing the shielding plate 21 inside the support case 25. 30 and a control means 40 for controlling the driving means 30 are accommodated.
[0017]
The shielding plate 21 is made of acrylic and is an opaque color plate (for example, black), and is formed in a size that can cover the front surface of the light projecting unit 4. Further, as shown in FIG. 2, a black sheet (corresponding to the reflection suppressing means of the present invention) 22 made of felt fiber is provided on the rear surface side (opposite surface side to the light projecting portion 4) of the shielding plate 21. It is pasted. This sheet 22 is used to prevent the light emitted from the light projecting unit 4 from being strongly reflected on the surface of the light shielding plate 21 when the light shielding plate 21 is positioned in front of the light projecting unit 4 (described later). belongs to. That is, the light emitted from the light projecting unit 4 is not directly reflected by the shielding plate 21 but enters the sheet 22 once. Since the sheet 22 is formed by irregularly overlapping fibers, the irradiation light is irregularly reflected and refracted inside the sheet 22. Accordingly, since the irradiation light is scattered in the sheet 22, the irradiation light is not strongly reflected on the surface of the shielding plate 21.
[0018]
The support case 25 is divided into an upper case 26 and a lower case 27. Of these, the upper case 26 is provided with side walls 26B and 26C facing downward on the left and right side edges of the substrate 26A forming the upper surface wall of the support case 25, and the front edge. On the other hand, the lower case 27 is provided with a side wall 27B at the rear edge of the substrate 27A that forms the lower wall of the support case 25. When these upper and lower cases 26 and 27 are assembled, a closed box is formed.
[0019]
Next, between the blocking position where the shielding plate 21 is positioned in front of the light projecting section 4 (the position indicated by the solid line in FIG. 3) and the open position where the light projecting section 4 is opened (the position indicated by the broken line illustrated in FIG. 3). The drive means 30 to be displaced will be described. As shown in FIG. 2, a rotating shaft 31 is rotatably attached to the upper case 26 through the side wall 26C left and right, and a pair of rotating arms 32, 33 are provided on the outer surface side of the left and right side walls 26C. Is attached in a state of being prevented from rotating with respect to the rotation shaft 31. The rotating arm 32 is formed in a U-shape, and attachment pieces 32A, 33A are bent inwardly on the front edge side. Of these, the right mounting piece 32A is screwed to the right side of the shielding plate 21, and the left mounting piece 33A is screwed to the left side of the shielding plate 21. In the attached state, the rotation shaft 31 is arranged in the direction along the front wall 3 of the liquid crystal projector 1 in the upper front part of the liquid crystal projector 1. For this reason, when both the rotating arms 32 and 33 are in a suspended posture, the shielding plate 21 is in front of the light projecting unit 4 and blocks the light projecting unit 4 (blocking position).
[0020]
A reduction gear 35 is attached to a position near the left end of the rotation shaft 31. On the other hand, a drive motor 38 is attached to the lower surface side of the substrate 26A of the upper case 26 via an L-shaped support bracket 37 that can be rotated in both forward and reverse directions. A pinion gear 39 that meshes with the reduction gear 35 is attached to the tip of the rotation shaft of the drive motor 38. The pinion gear 39 is formed with a smaller diameter than the reduction gear 35. As a result, the rotation of the drive motor 38 is decelerated via the pinion gear 39 and the reduction gear 35 and transmitted to the rotary shaft 31 as the drive motor 38 is driven. As a result, the driving means 30 moves the shielding plate 21 to the above-described blocking position, and the opening position where the driving unit 30 rotates approximately 90 degrees upward in the drawing from the blocking position and retracts to the upper front of the liquid crystal projector 1 to open the front of the light projecting unit 4. Rotating displacement between.
[0021]
Next, the control means 40 for detecting the position of the shielding plate 21 and controlling the drive motor 38 associated therewith will be described. The position detecting means may be constituted by an inductive, magnetic or photoelectric proximity switch. In this embodiment, as an example, a photoelectric proximity switch (hereinafter simply referred to as a proximity switch) is used. Yes. Specifically, a control board 41 is screwed to the board 26A of the upper case 26, and a pair of proximity switches 42 and 43 are attached side by side on the lower surface side thereof. Each of the proximity switches 42 and 43 includes a pair of LEDs (light emitting side) 42A and 43A and a phototransistor (light receiving side) 42B and 43B, and detection bodies 45 and 46 described below are provided for the proximity switches 42 and 43, respectively. When entering between the LEDs 42A, 43A and the phototransistors 42B, 43B, this is electrically detected. A pair of detection bodies 45 and 46 are provided with respect to the rotation shaft 31, and as shown in FIG. 2, the detection body 45 is mounted vertically and the detection body 46 is mounted sideways. Are in a positional relationship of approximately 90 degrees.
[0022]
Accordingly, as shown in FIG. 4, when the shielding plate 21 is in the blocking position, the detection body 45 is positioned between the LED 42A of the proximity switch 42 and the phototransistor 42B, and the detection body 46 is connected to the LED 43A of the proximity switch 43. It is retracted from between the phototransistor 43B. On the other hand, as shown in FIG. 5, when the shielding plate 21 is in the open position, the detection body 45 is now retracted from between the LED 42 </ b> A of the proximity switch 42 and the phototransistor 42 </ b> B, and the detection body 46 is the proximity switch 43. The LED 43A is located between the phototransistor 43B.
[0023]
Thus, the detection bodies 45 and 46 alternately enter between the LEDs 42A and 43A of the proximity switches 42 and 43 and the phototransistors 42B and 43B, so that the proximity switch 43 blocks the open position of the shielding plate 21 by the proximity switch 42. Each of the blocking positions of the plate 21 is detected. A light receiving sensor 48 for remote control operation is attached to the front edge of the lower surface of the board 41, and a circuit board constituting a motor control unit (not shown) is attached to the rear side of the board 41. The motor control unit is connected to the drive motor 38 via a drive circuit, and drives and stops the drive motor 38 based on control signals from the remote controller and the proximity switches 42 and 43.
[0024]
Next, the effect of this embodiment comprised as mentioned above is demonstrated.
As a procedure for attaching the light shielding device 10, the light shielding device 10 is directed to the liquid crystal projector 1 from above and set so that the shielding plate 21 is positioned on the front wall 3 side of the liquid crystal projector 1. The connection bracket 12 is attached to the upper surface side. Thereafter, alignment is performed by the slide mechanism 17 so that the shielding plate 21 is positioned in front of the light projecting unit 4 of the liquid crystal projector 1. This completes the attachment of the light shielding device 10 to the liquid crystal projector 1.
[0025]
Next, an operation of shifting the shielding plate 21 in the open position to the blocking position while the liquid crystal projector 1 is in use will be described. In the open position (see the alternate long and short dash line in FIG. 3), the shielding plate 21 is retracted to the upper front of the liquid crystal projector 1. Therefore, the front of the light projecting unit 4 is opened, and an image or the like can be projected on the screen. In this state, as shown in FIG. 5, the detection body 46 is located between the LED 43 </ b> A of the proximity switch 43 and the phototransistor 43 </ b> B, and the detection body 45 is in a positional relationship retracted from the proximity switch 42.
[0026]
From this state, when the switch of the drive motor 38 that is the drive source of the light shielding device 10 is turned on by the remote controller to drive the drive motor 38, the rotation shaft 31 rotates slowly due to the engagement of the pinion gear 39 and the reduction gear 35. Therefore, the shielding plate 21 is rotationally displaced from the P direction shown in FIG. 3, that is, from the open position to the cutoff position.
Together with this rotation operation, both detectors 45 and 46 also rotate. That is, the detection body 45 gradually approaches the proximity switch 42, and the detection body 46 gradually moves away from the proximity switch 43. Eventually, when the shielding plate 21 is rotationally displaced to the blocking position that covers the light projecting unit 4, the detection body 46 is completely separated from the proximity switch 43 and the detection body 45 is the LED 42A of the proximity switch 42 as shown in FIG. And the phototransistor 42B. As a result, the proximity switch 42 is activated and a control signal is sent to the motor control unit. Then, the motor control unit stops the supply of power to the drive motor 38 via the drive circuit. Thereby, the drive motor 38 and by extension, the shielding plate 21 are stopped.
[0027]
On the other hand, when returning from the blocking position to the open position, if the driving motor 38 is again operated (rotated in the reverse direction) by the remote controller, the shielding plate 21 is centered on the rotating shaft 31 and S in FIG. Rotating displacement in the direction. When the shielding plate 21 reaches the open position, the proximity switch 43 is activated and a control signal is sent to the motor control unit. Then, the motor control unit stops the supply of power to the drive motor 38 via the drive circuit. Thereby, the drive motor 38 and by extension, the shielding plate 21 are stopped.
[0028]
As described above, when the presenter performs the description without referring to the image on the screen, the situation where the presenter is exposed to the light source and the description is avoided if the light projecting unit 4 is blocked by the light shielding device 10 is avoided. And can effectively protect the presenter's vision. Further, since the light projecting unit 4 can be opened and closed while the power source of the liquid crystal projector 1 is connected, the light projecting unit 4 is opened immediately even if the light projecting unit 4 is interrupted once during the description. Can be done and will not hinder the progress of subsequent explanations.
Further, since these light shielding devices 10 are unitized, the liquid crystal projector 1 can be mounted by simply mounting the united light shielding device 10 and has excellent workability. .
[0029]
Further, the driving means 30 is provided with a rotating shaft 31 along the front wall 3 of the liquid crystal projector 1, and the shielding plate 21 is rotated and displaced in a region where the vent hole 6 is avoided. That is, even if the shielding plate 21 is in either the blocking position or the opening position, the ventilation opening 6 is not blocked and opened, so that ventilation is performed normally and hot air is not trapped in the casing.
[0030]
Furthermore, there exists the following advantage by making the shielding board 21 into a rotation type structure. The drive type may be a slide type in addition to the rotary type. In the case of the slide type, the shielding plate 21 is moved along the front wall 3 of the liquid crystal projector 1. However, with respect to the liquid crystal projector 1 having a small size, when the light projecting unit 4 and the ventilation opening 6 are provided on the front wall 3 of the liquid crystal projector 1, the space for avoiding the ventilation opening 6 and setting the opening position of the shielding plate 21. Cannot be secured on the front wall 3. In this case, it is necessary to set an open position on the outside of the casing 2, and it is also necessary to provide a guide for guiding the shielding plate 21 to the open position outside the casing. Therefore, when a slide type is applied to this type of liquid crystal projector 1, the guide portion protrudes from the outer shape of the liquid crystal projector 1 in the attached state.
[0031]
On the other hand, if it is a rotation type, the shielding plate 21 is supported in a state of being prevented from rotating around the rotation shaft 31 and is rotationally displaced about the axis. Therefore, even when the open position is set outside the casing 2, the shielding plate 21 can be opened and closed without providing a guide outside the casing 2. It becomes compact without jumping out from the outer shape of 1.
[0032]
Further, in consideration of manufacturing and mounting errors of the liquid crystal projector 1 and the light shielding device 10 and errors in the operation of the shielding plate 21, the shielding position in order to avoid the shielding plate 21 from interfering with the light projecting unit 4 at the shielding position. In FIG. 3, it is necessary to set a clearance avoidance gap (R dimension portion in FIG. 3) between the light projecting portion 4 and the shielding plate 21. However, if this gap is widened, the light irradiated from the light projecting unit 4 and reflected by the surface of the shielding plate 21 may leak from the gap. However, according to the present embodiment, the back side of the shielding plate 21 (the side facing the light projecting portion 4) is covered with the black felt sheet 22. Therefore, the sheet 22 can absorb the irradiation light from the light projecting unit 4. Further, the light that could not be absorbed enters the sheet 22, but the sheet 22 is made of irregular fibers, so that the incident irradiation light is irregularly refracted and reflected inside the sheet 22. Therefore, since the irradiation light is scattered in the sheet 22, the irradiation light is not strongly reflected on the surface of the shielding plate 21, and even if a part of the irradiation light leaks from the gap, it does not matter.
[0033]
Second Embodiment
A second embodiment of the present invention will be described with reference to FIG.
The first embodiment is an application example when the liquid crystal projector 1 is used while being suspended from the ceiling, but the second embodiment is an application example when the liquid crystal projector 1 is placed directly on the table 80.
As shown in FIG. 6, when the liquid crystal projector 1 is placed directly, the image from the light projecting unit 4 is projected on the screen by extending the front support leg 5 and tilting the liquid crystal projector 1. Adjust the position as follows.
[0034]
On the other hand, as the light shielding device 1, only the light shielding device main body 20 is used without using the mounting portion 11 of the first embodiment. That is, the shading device body 20 of the first embodiment is disposed in front of the liquid crystal projector 1 with the shielding plate 21 facing upward, and the shading device body 20 is shifted in the width direction of the liquid crystal projector 1 so that the shielding plate 21 is provided. Alignment is performed so that it is located in front of the light projecting unit 4.
In this way, since the rotation shaft 31 is positioned below the light projecting unit 4 if arranged, the shielding plate 21 covers the front of the light projecting unit 4 (solid line in FIG. 6) and the liquid crystal projector 1. Is rotated and displaced between the open position (the one-dot chain line in FIG. 6) where the light projecting unit 4 is opened by retreating to the lower front part. If the mounting portion 11 is removed and used in this manner, it can also be applied to the direct-type liquid crystal projector 1.
Since other configurations are the same as those in the first embodiment, the same components are denoted by the same reference numerals, and redundant description is omitted.
[0035]
<Other embodiments>
The present invention is not limited to the embodiments described with reference to the above description and drawings. For example, the following embodiments are also included in the technical scope of the present invention, and further, within the scope not departing from the gist of the invention other than the following. Various modifications can be made.
[0036]
(1) In the first and second embodiments, the liquid crystal projector 1 is used. However, the liquid crystal projector 1 does not need to be a liquid crystal and can be used for any projector as long as the light shielding device 10 can be attached.
[0037]
(2) In the first and second embodiments, the displacement operation of the shielding plate 21 is a rotation type, but it may be a slide type.
[Brief description of the drawings]
FIG. 1 is a perspective view of a liquid crystal projector and a projector shading device according to a first embodiment. FIG. 2 is an exploded perspective view of a projector shading device. FIG. 3 is a cross-sectional view showing an opening / closing operation of a shielding plate. FIG. 5 is a front view showing a state where the shielding plate is in an open position. FIG. 6 is a cross-sectional view showing an opening / closing operation of the shielding plate in the second embodiment.
DESCRIPTION OF SYMBOLS 1 ... Liquid crystal projector 2 ... Casing 4 ... Light projection part 6 ... Ventilation hole 10 ... Projector light-shielding device 21 ... Shielding board (shielding member)
30 ... Driving means 40 ... Control means

Claims (2)

A shielding member formed so as to shield a light projecting portion provided on a side surface of a projector including a casing, a blocking position for blocking the light projecting portion by positioning the shielding member in front of the light projecting portion, and A projector shading device comprising a drive means for displacing between an open position for opening a light projecting part and an attachment part attachable to the projector,
The casing is provided with a cooling fan for cooling the inside of the casing, and a ventilation port for the cooling fan is provided on a side surface on which the light projecting unit is disposed .
The driving means is provided with a rotation shaft for rotating the shielding member about the axis thereof in a direction along a side surface on which the light projecting portion is provided, and the light projecting portion is opened and closed by a rotation operation of the shielding member. As well as
A projector having a slide mechanism capable of manually adjusting a position of the shielding member on the side surface by sliding the shielding member along the side surface on which the light projecting portion is provided on the mounting portion. Shading device. The reflection suppressing means for suppressing reflection of the light irradiated from the light projecting portion on the shielding member is provided on a side surface of the shielding member facing the light projecting portion. 2. The projector shading device according to 1.

Images