JP2009037905A - Lamp unit, electric device installing the same, and method for driving electric device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lamp unit, capable of preventing a scattering of glass pieces, while sufficient cooling efficiency is secured. <P>SOLUTION: In the lamp unit 1, a metal mesh is formed at an inflow port 24 and an outflow port 25. For a heating means for raising the temperature of the metal mesh for eliminating dust, heat transmitted from a mercury lamp 11 through a reflector 12 and a heat-conductive part 22 is used. Metal of high heat conductivity is used for the heat-conductive part 22, and it is thermally put in contact with the metal mesh and the reflector 12 so as to increase heat transmission between them, thereby the temperature of the metal mesh is raised almost up to the temperature of the reflector 12. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a lamp unit having a light source therein, which is used by being incorporated in a device such as a projector and can be easily replaced by a user. The present invention also relates to an electric device in which the lamp unit is used and a driving method thereof.

  In a display device such as a projector, for example, a mercury lamp or the like is used as a light source having high emission intensity. The mercury lamp has a structure in which an electrode is provided in a glass tube and high-pressure mercury vapor is enclosed. This mercury lamp generates heat during use, and the glass tube may break if the temperature rises significantly. Therefore, it is essential to cool the mercury lamp during use of the projector. For this purpose, a structure in which the cooling air is sent to the mercury lamp is adopted.

  On the other hand, since the light emission intensity of a mercury lamp decreases during use due to various causes, the mercury lamp becomes a consumable item. Accordingly, not only when the glass tube is broken as described above, it is necessary to replace it periodically. Since this replacement is performed by the user, it takes the form of a lamp unit that facilitates this replacement work. In the lamp unit, a mercury lamp, a reflector, a glass window (light transmission window) and the like are integrated, and the user can easily perform this replacement work without directly touching the mercury lamp.

  The projector in which the lamp unit is incorporated is provided with an air cooling fan. In this lamp unit, as described above, a structure is adopted in which the cooling air generated from the air cooling fan efficiently hits the mercury lamp and sufficient cooling is performed. On the other hand, as described above, the glass tube of the mercury lamp may be broken. In this case, it is dangerous if glass pieces may be scattered when the user replaces the lamp unit. Therefore, a structure has been proposed in which cooling air is efficiently introduced and glass pieces are less likely to be scattered outside the lamp unit.

  For example, Patent Document 1 describes a structure in which cooling air is efficiently sent to a mercury lamp, but a glass piece is provided with a barrier that is difficult to scatter to the outside between the lamp unit and the lamp unit mounting portion of the projector. Has been.

  In Patent Documents 2, 3, and 4, an opening / closing mechanism is provided in a ventilation window in the lamp unit, and this window is opened when the lamp unit is attached to the projector, and this window is opened when the lamp unit is removed. The closing structure is described.

  Patent Documents 5 and 6 describe a structure in which air permeability is ensured and glass pieces are prevented from being scattered by providing a mesh in a ventilation window. Here, since the mesh is easily clogged with glass pieces and dust, the technology described in Patent Document 5 is provided with a protective wall having a structure for preventing the glass pieces from scattering to the metal mesh (ventilation window). . In the technique described in Patent Document 6, an air filter is provided in a ventilation portion that sends cooling air to the mesh, and in particular, adhesion of dust to the mesh is suppressed.

With these technologies, a lamp unit is obtained that is safe and easy for users to replace and that has a high cooling efficiency for mercury lamps. The projector using this could be used safely.
JP-A-8-314011 Japanese Patent Laid-Open No. 11-237691 Japanese Patent Laid-Open No. 11-329015 JP 2001-330890 A WO 2004-74927 JP 2006-11337 A

  However, in the technologies described in Patent Documents 1 to 4, although the cooling efficiency is increased, as shown below, the scattering of the glass pieces is not sufficiently prevented.

  In the technique described in Patent Document 1, scattering from the exhaust side window in the lamp unit is prevented, but the glass piece may also be scattered from the intake side window, and this cannot be dealt with. If a barrier is also provided on the intake side, the cooling efficiency is lowered.

  In the techniques described in Patent Documents 2, 3, and 4, the cooling efficiency can be secured, and the glass pieces can be prevented from scattering after the lamp unit is removed. However, since the window is open while the lamp unit is attached, if the glass tube breaks during that time, scattering from the window cannot be prevented.

  On the other hand, in the techniques described in Patent Documents 5 and 6 in which a mesh is provided in the window, scattering of a particularly large glass piece is prevented, so that sufficient safety is ensured when the user replaces the lamp unit. . However, as shown below, the cooling efficiency is not sufficient.

  In the technique described in Patent Document 5, scattering of glass pieces to the mesh is prevented. However, the scattering in this case is from the downstream side of the cooling air as viewed from the mesh. Therefore, it is rare that a large piece of glass is originally sucked into the mesh on the intake side, and it is the dust sucked from the upstream side of the ventilation as viewed from the mesh that actually affects the ventilation of the mesh. This structure is completely ineffective against this dust, which can clog the mesh and reduce cooling efficiency.

  In the technique described in Patent Document 6, it is particularly suppressed that dust adheres to the mesh. However, due to the presence of the air filter, the cooling efficiency is lowered, and the power consumption of the cooling fan is increased in order to obtain the same cooling efficiency as that without the air filter. Further, when the air filter is clogged, the cooling efficiency is lowered, and the replacement work is required.

  Therefore, it has been difficult to obtain a lamp unit that has ensured sufficient cooling efficiency while preventing scattering of glass pieces.

  The present invention has been made in view of such problems, and an object thereof is to provide an invention that solves the above problems.

In order to solve the above problems, the present invention has the following configurations.
In the lamp unit of the present invention, a reflector, a light source fixed in the reflector, a light transmission window that transmits light emitted from the light source, and cooling air that cools the light source through a metal mesh are introduced. The lamp unit includes an inlet and is used by being incorporated in an electric device, and is characterized by being provided with heating means for heating the metal mesh to a temperature of 200 ° C. or higher.
In the lamp unit of the present invention, the heating means includes the light source, the reflector, and a heat transfer section that is in thermal contact with the reflector and the metal mesh.
In the lamp unit of the present invention, the normal line of the light transmission window is inclined with respect to the optical axis of the light emitted from the lamp unit, and the heating means irradiates the reflector with the reflected light from the light transmission window. It is characterized by utilizing the heat generated at the location.
The lamp unit according to the present invention is characterized in that heat is conducted to the metal mesh through a target adjacent to a portion where the reflected light is applied to the reflector.
The lamp unit of the present invention is characterized in that a heating wire is provided on the metal mesh.
The lamp unit of the present invention further includes an outlet through which the cooling air flows out through a metal mesh.
In the lamp unit of the present invention, the opening of the metal mesh at the outlet is larger than the opening of the metal mesh at the inlet.
The electric apparatus according to the present invention is characterized in that the lamp unit is incorporated and air cooling means for generating the cooling air is provided.
The electric device of the present invention is a projector.
The method for driving an electric device according to the present invention is a method for driving the electric device, characterized in that a cooling stop period for temporarily stopping the generation of the cooling air is provided.
The method for driving an electric device according to the present invention is characterized in that the cooling stop period is provided periodically.
The electric device driving method of the present invention is characterized in that the cooling stop period is provided when the electric device is started and / or disconnected.

  Since this invention is comprised as mentioned above, while preventing scattering of a glass piece, the lamp unit which ensured sufficient cooling efficiency can be obtained.

  Hereinafter, the best mode for carrying out the present invention will be described. The lamp unit in the embodiment described below is used by being incorporated in an electric device, for example, a projector, and emits light emitted from a light source fixed in the reflector through a light transmission window. This projector has air cooling means for generating cooling air for cooling the light source in the lamp unit. In this lamp unit, a metal mesh is provided at the inlet through which the cooling air flows. The metal mesh is provided with a heating means for raising its temperature, whereby fine dust that obstructs ventilation is efficiently removed. At this time, the temperature of the metal mesh is set to 200 ° C. or higher by this heating means.

(First embodiment)
FIG. 1 is a schematic cross-sectional view of the lamp unit 1 according to the first embodiment of the present invention. The light emitted from the mercury lamp 11 serving as the light source in the lamp unit 1 is reflected by the inner surface of the reflector 12 around it as shown by the broken line in the figure, and is a light transmission window 21 provided in the lamp lid portion 20. To the direction of the optical axis 13. This light is incident on an optical system (not shown) of a projector in which the lamp unit 1 is incorporated and used to generate the video output. The cross section in FIG. 1 is a cross section along the direction of the emitted optical axis 13. The mercury lamp 11 is fixed by the lamp column 14 in the reflector 12, and the lamp lid 20 and the reflector 12 are also fixed.

  The lamp lid portion 20 includes a light transmission window 21, a heat transfer portion 22, and a light transmission window support portion 23. Further, an inflow port 24 is provided on the upper side in FIG. 1 of the lamp lid portion 20, and an outflow port 25 is provided on the lower side.

  The light transmission window 21 is configured by transmitting visible light used in the projector and reflecting infrared light or ultraviolet light, for example, by adding a multilayer filter on the incident surface side. The heat transfer part 22 is made of a metal having a high thermal conductivity, such as an aluminum material. The light transmission window support portion 23 is made of, for example, ceramic or plastic material having low thermal conductivity. As shown in FIG. 1, the light transmission window 21 is installed at an angle with a normal line inclined from the optical axis. This is for suppressing that the component which reflected on the surface among the light which injected into the light transmission window 21 returns to the mercury lamp 11, and further promotes the heating.

  A top view of the lamp unit 1 is shown in FIG. 2, and a bottom view thereof is shown in FIG. On the upper surface (FIG. 2) of the lamp lid portion 20, an inflow port 24 is provided in the heat transfer unit 22, and on the bottom surface (FIG. 3), an outflow port 25 is provided in the heat transfer unit 22. When the lamp unit 1 is incorporated in a projector, cooling air generated by an air cooling means (for example, a cooling fan) provided in the projector is introduced from the inlet 24 and out from the outlet 25. Thereby, the mercury lamp 11 is cooled. Here, a metal mesh is formed at the inlet 24 and the outlet 25. For example, the opening of the metal mesh can be set to about 1.8 mm, and an object larger than this can not pass through it.

  Therefore, since the metal mesh is provided in the inflow port 24 and the outflow port 25, even if the glass tube of the mercury lamp 11 is broken, the glass piece is prevented from coming out of the lamp unit 1. Therefore, the user can safely replace the lamp unit 1.

  Here, in particular, when the opening of the metal mesh is small, it is possible to prevent scattering of finer glass pieces. On the other hand, there is a high possibility that clogging will occur due to dust, particularly at the inlet 24. In this case, the cooling efficiency decreases.

  On the other hand, in the lamp unit 1, heat transmitted from the mercury lamp 11 through the reflector 12 and the heat transfer unit 22 is used as a heating means for removing the dust by raising the temperature of the metal mesh. . That is, the temperature rise of the reflector 12 by the mercury lamp 11 is used. For this reason, the material of the heat transfer section 22 is made of a metal having a high thermal conductivity, and is brought into thermal contact with the metal mesh and the reflector 12 to increase the heat conduction therebetween, whereby the metal is brought close to the temperature of the reflector 12. Increase the temperature of the mesh. On the other hand, if the temperature rise of the light transmission window 21 is large, the light transmission window 21 may be cracked. Therefore, in order to suppress heat conduction to the light transmission window 21, the light transmission window support portion to which the light transmission window 21 is fixed. The thermal conductivity of 23 material is made low.

  Most of the light emitted from the mercury lamp 11 enters the reflector 12 and reflects it. Therefore, the surface temperature becomes high. The temperature of the reflector 12 when the lamp unit 1 is actually used is, for example, about 200 to 500 ° C. when the output of the mercury lamp 11 is about 275 W. On the other hand, dust adhering to the metal mesh is dust floating in the air, and is incinerated at a temperature of about 200 ° C. and removed. Therefore, when the temperature of the metal mesh becomes 200 ° C. or higher by the above structure, clogging of the metal mesh due to dust is prevented.

On the other hand, if the metal mesh becomes high temperature, the cooling air passing through the metal mesh also becomes high temperature, and it is considered that the cooling efficiency decreases. However, for example, the flow rate of cooling air is 0.2 m ³ / min, the air temperature is 40 ° C., the air density is 1.0 kg / m ³ , the constant pressure specific heat of air is 1000 J / kg · K, and the inlet 24 ( When the heat generation amount of the metal mesh) is 20 W, the temperature rise of the air (cooling air) when passing through the metal mesh is 6 ° C. Since the temperature at the time of light emission of the mercury lamp 11 is 700 to 900 ° C., this temperature rise can be ignored. Therefore, the decrease in cooling efficiency due to the high temperature of the metal mesh can be ignored. On the other hand, the temperature of the reflector 12 decreases as the heat conduction from the reflector 12 to the metal mesh is improved to increase the temperature of the metal mesh. Accordingly, heat dissipation of the mercury lamp 11 through the reflector 12 is promoted. Therefore, the cooling efficiency of the mercury lamp 11 is not deteriorated by this structure.

  In addition, since the dust which passed the metal mesh of the inflow port 24 has high possibility of burning in the reflector 12 which becomes high temperature, possibility that this dust will clog the metal mesh of the outflow port 25 is low. Therefore, the heating means for heating the metal mesh can be provided only for the metal mesh on the inlet 24 side. Further, the opening of the metal mesh on the outlet 25 side may be made smaller than the opening of the metal mesh on the inlet 24 side.

  Therefore, in this lamp unit 1, scattering of glass pieces is prevented, and sufficient cooling efficiency is ensured. The same applies to projectors using this.

  Moreover, since the heat generated by the mercury lamp 11 itself is used as a heat source for the heating means used here, the power consumption does not increase. Therefore, sufficient cooling efficiency is ensured without increasing power consumption.

  Although the cooling efficiency of the mercury lamp 11 is lowered by stopping the air cooling means, the metal mesh can be heated more efficiently. For this reason, dust can be more efficiently removed by providing a cooling stop period in which the air cooling means is stopped for a certain period of time. This cooling stop period can be set at regular intervals during the operation of the projector, for example. The cooling stop period can be set at an arbitrary timing. However, since the temperature of the reflector 12 is particularly increased when the projector is cut off, the temperature of the metal mesh can be raised particularly if the air cooling means is stopped at this time. it can. In this case, at the time of disconnection, the air cooling means may be stopped first, and power supply to the mercury lamp 11 may be stopped after a certain time has elapsed.

(Second Embodiment)
FIG. 4 is a schematic sectional view of a lamp unit 30 according to the second embodiment of the present invention, FIG. 5 is a top view thereof, and FIG. 6 is a bottom view thereof. The mercury lamp 31, the reflector 32, the optical axis 33, the lamp column 34, and the lamp lid 40 in the lamp unit 30 are the same as those in the first embodiment. The same applies to the light transmission window 41, the heat transfer section 42, the light transmission window support section 43, the inlet 44, and the outlet 45 in the lamp lid 40, and a metal mesh is provided at the inlet 44 and the outlet 45. The same applies to points. However, here, a metal target 35 is connected to the heat transfer section 42. The target 35 is adjacent to a portion irradiated on the reflector 32, and heat conduction to the metal mesh is promoted through the target 35.

  As shown in FIG. 4, among the light components emitted from the mercury lamp 31, visible light used in the projector passes through the light transmission window 41 and is collected at a point M before entering the optical system of the projector. On the other hand, of the light components emitted from the mercury lamp 31, components other than visible light, such as ultraviolet light and infrared light, are reflected by the surface of the light transmission window 41. As shown in FIG. 4, since the light transmission window 41 is installed to be inclined with respect to the optical axis, the reflected light is incident on the surface of the reflector 32 at a location off the mercury lamp 31, and this location is Heat. Therefore, if the target 35 is installed at this location, the temperature rises. Alternatively, of the light reflected by the surface of the reflected light transmission window 41, for example, a part of the infrared light is transmitted through the reflector 32, but this is also converted into heat by receiving the surface of the reflector 32. Therefore, the light reflected by the surface of the light transmission window 41 is efficiently converted into heat by the target 35, and the generated heat can be more efficiently transmitted to the metal mesh at the inlet 44. That is, in the lamp unit 30, heat generated at a location where the reflected light from the light transmission window 41 is irradiated onto the reflector 32 is used as a heating unit.

  Therefore, also in this lamp unit 30, scattering of glass pieces is prevented, and sufficient cooling efficiency is ensured. The same applies to projectors using this.

  Further, since light emission or heat generation from the mercury lamp 31 itself is used as a heat source of the heating means used here, this does not increase power consumption.

  Moreover, since heat generated from the mercury lamp 31 is efficiently transmitted to the metal mesh through the reflector 32, heat dissipation from the mercury lamp 31 is promoted.

  It is also possible to irradiate the metal mesh directly with the reflected light from the light transmission window 41 by adjusting the installation angle of the light transmission window 41 and the position of the inlet 44. In this case, the target 35 is not necessary. However, particularly when the interval between the metal meshes is large, it is preferable to use the target 35 because the efficiency of absorbing the reflected light is lowered by the metal mesh itself.

  Further, similarly to the first embodiment, the efficiency of removing dust can be further increased by providing a cooling stop period.

(Third embodiment)
FIG. 7 is a schematic cross-sectional view of a lamp unit 50 according to the third embodiment of the present invention, FIG. 8 is a top view thereof, and FIG. 9 is a bottom view thereof. The mercury lamp 51, the reflector 52, the mercury lamp column 54, and the light transmission window 61 in the lamp unit 50 are the same as those in the first and second embodiments.

  The lamp lid part 60 includes a light transmission window 61 and a lamp lid part body 66. On the upper surface (FIG. 8) of the lamp lid 60, an inlet 64 is provided in the lamp lid main body 66, and on the bottom (FIG. 9), an outlet 65 is provided in the lamp lid main body 66. . The functions of the inflow port 64 and the outflow port 65 are the same as those in the first and second embodiments. Here, as the material of the lamp lid main body, a material having a low thermal conductivity, for example, a ceramic material or a plastic material is used as in the case of the light transmission window support portion 23 in the first embodiment.

  Here, electric heating means is used as the heating means in the lamp unit 50, and a nichrome wire (heating wire) 68 is installed on the metal mesh at the inlet 64. By passing a current between the terminals AB in FIG. 8, the nichrome wire is heated and the metal mesh is heated. Thereby, the dust adhering to the metal mesh is removed.

  Therefore, also in this lamp unit 50, scattering of glass pieces is prevented and sufficient cooling efficiency is ensured.

  Here, in order to efficiently heat only the metal mesh at the inlet 64, the thermal conductivity of the lamp lid main body 66 is reduced and the heating of the light transmission window 61 is suppressed. In FIGS. 7 to 9, the nichrome wire 68 is provided only at the inflow port 64 and not at the outflow port 65, but may be provided at the outflow port 65. Further, similarly to the first embodiment, the opening of the metal mesh on the outflow port 65 side may be wider than the opening of the metal mesh on the inflow port 64 side.

  In the first and second embodiments, since the mercury lamp itself is used as a heat source in the heat generating means, at least the metal mesh at the inlet is always high when the mercury lamp is driven. On the other hand, in this lamp unit 50, since the mercury lamp 51 is not a heat source, the timing at which the metal mesh is heated can be arbitrarily set.

  Therefore, as in the first and second embodiments, the dust can be removed particularly efficiently by providing a cooling stop period and passing a current through the nichrome wire 68 during the cooling stop period.

  Although this timing is arbitrary, for example, it can be performed at a constant period during the operation of the projector. Similar to the first embodiment, this can also be done when the projector is disconnected. In the third embodiment, the heat source is not the mercury lamp 51 but the nichrome wire 68. Therefore, a cooling stop period is provided when the projector is started, and a current is passed through the nichrome wire 68 so that the metal mesh is heated to a high temperature. In addition, dust can be efficiently removed. Alternatively, a period for energizing the nichrome wire 68 may be set separately from the cooling stop period.

  In the first and second embodiments, the heat generated by the mercury lamp is exclusively used as the heat source. In the lamp unit 50, the amount of heat generated can be freely controlled by the current flowing through the nichrome wire 68. it can. For example, when the projector is in a dust-free environment, it is possible not to drive the heat-generating means, but to control the heat-generating means only when the projector is in a dusty environment or to change the current value depending on the environment. is there.

  The first or second embodiment described above and the third embodiment can also be used in combination. In this case, the dust removal capability is further enhanced.

  In the above example, a mercury lamp is used as the light source. However, the present invention is not limited to this, and any replaceable light source can be installed and used in the lamp unit. Is clear.

  In the above example, the case where the device in which the lamp unit is incorporated is a projector has been described. However, the invention is not limited to this, and the projector of the present invention is applied to a device using a replaceable lamp unit. It is clear that cooling methods can be applied.

It is sectional drawing of the lamp unit used as the 1st Embodiment of this invention. It is a top view of the lamp unit used as the 1st embodiment of the present invention. It is a bottom view of the lamp unit used as the 1st embodiment of the present invention. It is sectional drawing of the lamp unit used as the 2nd Embodiment of this invention. It is a top view of the lamp unit used as the 2nd Embodiment of this invention. It is a bottom view of the lamp unit used as the 2nd Embodiment of this invention. It is sectional drawing of the lamp unit used as the 3rd Embodiment of this invention. It is a top view of the lamp unit used as the 3rd embodiment of the present invention. It is a bottom view of the lamp unit used as the 3rd embodiment of the present invention.

Explanation of symbols

1, 30, 50 Lamp unit 11, 31, 51 Mercury lamp 12, 32, 52 Reflector 13, 33 Optical axis 14, 34, 54 Lamp column 20, 40, 60 Lamp cover 21, 41, 61 Light transmission window 22, 42 Heat transfer section 23, 43 Light transmission window support section 24, 44, 64 Inlet 25, 45, 65 Outlet 35 Target 66 Lamp cover body 68 Nichrome wire (heat generation line)

Claims (12)

A reflector, a light source fixed in the reflector, a light transmission window that transmits light emitted from the light source, and an inlet through which cooling air that cools the light source flows through a metal mesh, A lamp unit used by being incorporated in an electric device,
A lamp unit comprising a heating means for heating the metal mesh to a temperature of 200 ° C. or higher. The heating means includes
The light source;
The reflector;
A heat transfer portion in thermal contact with the reflector and the metal mesh;
The lamp unit according to claim 1, comprising:   The normal line of the light transmission window is inclined with respect to the optical axis of the light emitted from the lamp unit, and the heating means uses the heat generated at the point where the reflected light from the light transmission window is irradiated to the reflector. The lamp unit according to claim 1 or 2.   The lamp unit according to claim 3, wherein heat is conducted to the metal mesh through a target adjacent to a portion where the reflected light is applied to the reflector.   The lamp unit according to any one of claims 1 to 4, wherein a heating wire is provided on the metal mesh.   The lamp unit according to any one of claims 1 to 5, further comprising an outlet through which the cooling air flows out through a metal mesh.   The lamp unit according to claim 6, wherein an opening of the metal mesh at the outlet is smaller than an opening of the metal mesh at the inlet.   An electric device comprising the lamp unit according to any one of claims 1 to 7, and air cooling means for generating the cooling air.   The electric device according to claim 8, wherein the electric device is a projector. It is a drive method of the electric equipment of Claim 8, Comprising:
A method for driving an electric device, characterized by providing a cooling stop period for temporarily stopping the generation of the cooling air.   The method of driving an electric device according to claim 10, wherein the cooling stop period is periodically provided.   The method for driving an electric device according to claim 10, wherein the cooling stop period is provided when the electric device is started and / or disconnected.

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