Image irradiation device

Abstract

In an image illumination device configured to illuminate an image display unit with light emitted from an image generation unit via a reflector, the positional accuracy of the reflector is improved. [Solution] The second reflector 40, which reflects light emitted from the image generation unit toward the image display unit, is provided with a base end 46B of a lever member 46 for rotating the second reflector 40 around an axis Ax extending in the left-right direction. Furthermore, the spring piece 84 of a pressing member 80 attached to the first housing 52 elastically presses the outer circumferential surface of the base end 46B, thereby improving the positional accuracy of the second reflector 40. At that time, the portion of the base end 46B that is pressed by the spring piece 84 is configured as a plate cam portion 46E, so that the second reflector 40 is biased in one direction (i.e., in the direction of rotation toward the rear around the axis Ax), thereby further improving the positional accuracy of the second reflector 40.

Description

Technical Field

[0001] The present invention relates to an image irradiation device configured to project a display image onto an image display unit.

Background Art

[0002] Conventionally, as an in-vehicle image irradiation device, there is known one configured to project a display image onto an image display unit such as a front window (i.e., a windshield) or a light-transmitting plate disposed on the vehicle interior side thereof, while being disposed inside the vehicle cabin.

[0003] In "Patent Document 1", there is described such an image irradiation device including an image generation unit that generates a display image, a reflecting mirror that reflects the emitted light from this image generation unit toward the image display unit, and a housing that houses this reflecting mirror.

[0004] The image irradiation device described in this "Patent Document 1" has a configuration in which the reflecting mirror is supported by the housing so as to be rotatable about an axis extending in a required direction. At that time, a shaft member extending in the required direction is provided at a side end portion of the reflecting mirror, and the housing has a configuration in which a first housing and a second housing are assembled. A bearing portion for supporting the shaft member of the reflecting mirror is formed in the first housing, and a contact portion that contacts the outer peripheral surface of the shaft member supported by this bearing portion is formed in the second housing.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] As described in "Patent Document 1" above, by providing a configuration in which the reflector is supported so as to be rotatable around an axis extending in the required direction, it becomes possible to adjust the height position of the displayed image according to the driver's height, preferences, etc.

[0007] Furthermore, if the image irradiation device described in "Patent Document 1" above is configured such that the contact portion formed on the second housing contacts the outer circumferential surface of the shaft member supported by the bearing portion of the first housing, it becomes possible to position the shaft member of the reflector with respect to a direction intersecting the required direction.

[0008] However, considering the effects of vehicle vibration and other factors, it is desirable to improve the positional accuracy of the reflector by securely holding it in a predetermined position, from the standpoint of accurately displaying the image on the image display unit.

[0009] It should be noted that these same issues can also arise in image projection devices other than those used in vehicles.

[0010] The present invention has been made in view of these circumstances, and aims to provide an image illumination device that can improve the positional accuracy of the reflecting mirror in an image illumination device configured to illuminate an image display unit with light emitted from an image generation unit via a reflecting mirror. [Means for solving the problem]

[0011] The present invention aims to achieve the above objective by modifying the positioning structure of the reflecting mirror.

[0012] In other words, the image irradiation device according to the present invention is In an image projection device configured to display an image on an image display unit, The system comprises an image generation unit that generates the above-mentioned display image, a reflector that reflects the light emitted from the image generation unit toward the image display unit, and a housing that accommodates the reflector. The above-mentioned reflector is supported in the housing so as to be rotatable about an axis extending in the required direction. Furthermore, The invention of the first application is, A shaft member extending in the required direction is provided at the side end of the above-mentioned reflecting mirror. The housing has a bearing portion formed therein for supporting the shaft member. A pressing member is attached to the housing above, which elastically presses against the outer circumferential surface of the shaft member supported by the bearing portion above. The shaft member described above is characterized in that the portion pressed by the pressing member has a plate-cam-shaped outer surface with the axis as its center, The second invention of this application is, A shaft member extending in the required direction is provided at the side end of the above-mentioned reflecting mirror. The above housing consists of a first housing and a second housing assembled together. The first housing described above has a bearing portion formed therein for supporting the shaft member. The second housing is characterized in that a pressing piece is integrally formed thereon, which elastically presses against the outer circumferential surface of the shaft member supported by the bearing portion. The third invention of this application is, The housing is provided with a shaft member extending in the required direction. A plate-shaped flange portion is formed at the side end of the above-mentioned reflector, extending in a direction intersecting the required direction. A recess is formed on the tip surface of the plate-shaped flange portion, which engages with the shaft member of the bracket. The plate-shaped flange portion is characterized by having a pressing member attached to it that elastically presses against the outer circumferential surface of the shaft member, which is engaged with the recess. The fourth invention of this application is, A bearing member having a spherical recess is attached to either the reflector or the housing at two locations in the required direction. A pivot member having spherical tip portions formed so as to fit into the spherical concave portions is attached to two locations in the above-mentioned required direction on either the above-mentioned mirror or the other of the above-mentioned housing.

[0013] The above-mentioned "image irradiation device" is not particularly limited in its specific use as long as it is configured to project a display image onto an image display unit. For example, applications such as in-vehicle head-up displays can be adopted.

[0014] The specific direction of the above-mentioned "required direction" is not particularly limited, and for example, a horizontal direction or the like can be adopted.

[0015] The specific configuration of the above-mentioned "image display unit" is not particularly limited as long as it is configured to project a display image. For example, a vehicle's front window or a light-transmitting plate arranged on the interior side of the vehicle cabin can be adopted.

[0016] The specific shape of the reflecting surface and the like of the above-mentioned "mirror" are not particularly limited as long as it is configured to reflect the emitted light from the image generation unit toward the image display unit.

[0017] The above-mentioned "shaft member" may be composed of a member separate from the mirror (or housing), or may be configured as a part of the mirror (or housing).

Advantages of the Invention

[0018] In the image irradiation device according to the present invention, the mirror for reflecting the emitted light from the image generation unit toward the image display unit is supported so as to be rotatable around an axis extending in a required direction with respect to the housing that houses it. Therefore, the height position of the display image can be adjusted according to the height and preferences of the driver.

[0019] Furthermore, in the first invention of the present application, A shaft member extending in the required direction is provided at the side end of the reflector, and a bearing portion is formed in the housing to support the shaft member. Furthermore, a pressing member is attached to the housing that elastically presses against the outer circumferential surface of the shaft member supported by the bearing portion. As a result, the reflector can be securely held in a predetermined position, thereby improving the positional accuracy of the reflector.

[0020] Furthermore, since the shaft member has a plate-cam shaped outer surface centered on the axis in the portion pressed by the pressing member, the reflector can be held in a state biased in one direction with respect to its rotational direction by its outer surface contacting the pressing member, thereby further improving the positional accuracy of the reflector.

[0021] In the present invention, the second invention, A shaft member extending in the required direction is provided at the side end of the reflector, and the housing is configured by assembling a first housing and a second housing. The first housing has a bearing portion that supports the shaft member, and the second housing has a pressing piece integrally formed that elastically presses the outer circumferential surface of the shaft member supported by the bearing portion. As a result, the reflector can be securely held in a predetermined position, thereby improving the positional accuracy of the reflector.

[0022] Moreover, this can be achieved through a predetermined process of assembling the first and second housings, thereby enabling the image irradiation device to have an inexpensive configuration.

[0023] In the third invention of this application, The housing is provided with a shaft member extending in the required direction, while the side end of the reflector has a plate-shaped flange portion formed in a direction intersecting the required direction, and a recess is formed on the tip surface of this plate-shaped flange portion to engage with the shaft member. Furthermore, a pressing member is attached to this plate-shaped flange portion to elastically press the outer circumferential surface of the shaft member that is engaged with the recess, so that the reflector can be securely held in a predetermined position, thereby improving the positional accuracy of the reflector.

[0024] Furthermore, by configuring the shaft member to engage with the recess in the plate-shaped flange portion in this way, the size of the reflector can be reduced in the required direction, thereby enabling a more compact image illumination device.

[0025] In the fourth invention of this application, A bearing member having spherical recesses is provided at two locations in the required direction on either the reflector or the housing, while a pivot member having a spherical tip formed to fit into the spherical recesses is provided at two locations in the required direction on either the reflector or the housing. By fitting these pair of spherical recesses and pair of spherical tips, the reflector is supported so as to be rotatable around the axis relative to the housing, and the positional accuracy of the reflector can be improved.

[0026] Moreover, this can be achieved with a simple configuration consisting only of fitting together a pair of spherical recesses and a pair of spherical tips, thereby enabling an inexpensive image irradiation device.

[0027] In the fourth invention of this application, the bearing member may be composed of a separate member from either the reflector or the housing, or may be composed as part of either the reflector or the housing, and the pivot member may be composed of a separate member from either the reflector or the housing, or may be composed as part of either the reflector or the housing. [Brief explanation of the drawing]

[0028] [Figure 1] Side cross-sectional view showing the image irradiation device according to the first embodiment of the present invention mounted on a vehicle. [Figure 2] View from the direction arrow II in Figure 1 [Figure 3] Detailed view of part III in Figure 1 [Figure 4] Plan view showing the above image projection device with the second housing removed. [Figure 5] Figure 4: Cross-sectional view along line VV [Figure 6] Figure 5, section view along line VI-VI [Figure 7] Detailed view of part VII in Figure 5 [Figure 8] Figure 6 shows a second embodiment of the present invention. [Figure 9] A figure similar to Figure 7 shows the second embodiment described above. [Figure 10] A figure similar to Figure 6 shows a third embodiment of the present invention. [Figure 11] View in direction XI of Figure 10 [Figure 12] A figure similar to Figure 10, showing the main components of the third embodiment described above in an exploded state. [Figure 13] Figure 6 shows a fourth embodiment of the present invention. [Figure 14] Figure 13 is similar to Figure 13, showing the main components of the fourth embodiment described above in an exploded state. [Figure 15] A figure similar to Figure 13 shows a modified example of the fourth embodiment described above. [Modes for carrying out the invention]

[0029] Embodiments of the present invention will be described below with reference to the drawings.

[0030] First, a first embodiment of the present invention will be described.

[0031] Figure 1 is a side cross-sectional view showing the image illumination device 10 according to this embodiment mounted on a vehicle 100. Figure 2 is a view taken in the direction of arrow II in Figure 1.

[0032] In Figures 1 and 2, the direction indicated by X is the "forward" direction for the image projection device 10 (and also the "forward" direction for the vehicle), the direction indicated by Y is the "leftward" direction perpendicular to the "forward" direction, and the direction indicated by Z is the "upward" direction. The same applies to figures other than Figures 1 and 2.

[0033] As shown in Figures 1 and 2, the image projection device 10 according to this embodiment is an in-vehicle head-up display that, when placed inside the vehicle 100, is configured to project a display image PIC as a virtual image onto an image display unit 102A set on the inner surface of the front windshield 102.

[0034] The optical path R shown in Figure 1 is the optical path through which the driver 2 visually perceives the display image PIC projected onto the image display unit 102A by the image projection device 10.

[0035] The image display unit 102A is positioned in the lower area of ​​the front windshield 102 and in front of the steering wheel 104, and is set as a horizontally elongated rectangular area. This allows the driver 2 of the vehicle 100 to easily visually recognize the display image PIC projected onto the image display unit 102A.

[0036] Figure 2 shows a specific example of a display image PIC, where the vehicle speed (50 km / h) is displayed along with a leftward-pointing arrow.

[0037] The image projection device 10 is positioned in front of the steering wheel 104 and near the bottom of the front windshield 102.

[0038] As shown in Figure 1, the image projection device 10 comprises an image generation unit 20 that generates a display image which will be the basis for the display image PIC, first and second reflectors 30 and 40 that sequentially reflect the light emitted from the image generation unit 20 toward the image display section 102A of the front window 102, a housing 50 that houses these components, and a light-transmitting cover 60 mounted on the housing 50.

[0039] The image generation unit 20 and the first and second reflectors 30 and 40 are supported by the housing 50 (which will be described later).

[0040] The housing 50 is configured such that the second housing 54 is assembled to the first housing 52, which is formed to open upwards.

[0041] Figure 3 is a detailed view of part III of Figure 1. Figure 4 is a plan view showing the image irradiation device 10 with the second housing 54 removed, and Figure 5 is a cross-sectional view taken along line VV of Figure 4.

[0042] As shown in Figures 3 to 5, the second housing 54 has an outer peripheral flange portion 54b, and is assembled to the first housing 52 with this outer peripheral flange portion 54b in contact with the upper end opening 52a of the first housing 52.

[0043] The first and second housings 52 and 54 are both made of opaque resin molded products. The second housing 54 has an opening 54a formed therein to transmit reflected light from the second reflector 40 toward the image display unit 102A.

[0044] The light-transmitting cover 60 is made of a colorless, transparent resin panel. This light-transmitting cover 60 is positioned to cover the opening 54a of the second housing 54, with a downward curve and a slight upward inclination toward the rear. This light-transmitting cover 60 allows reflected light from the second reflector 40 to enter the image display unit 102A, while ensuring dustproofing of the internal space 12 of the housing 50.

[0045] As shown in Figures 4 and 5, the first and second reflecting mirrors 30 and 40 have symmetrical reflective surfaces 30a and 40a, and the image generation unit 20 is positioned at the center of these mirrors in the left-right direction.

[0046] The image generation unit 20 includes a liquid crystal panel 22 having a rectangular external shape, and this liquid crystal panel 22 is positioned to face the internal space 12 of the housing 50. Specifically, the image generation unit 20 is supported by the lower wall portion 52b of the first housing 52 with the longitudinal direction of the liquid crystal panel 22 extending in the left-right direction (i.e., the vehicle width direction), and with the liquid crystal panel 22 facing diagonally upward and backward.

[0047] The image generation unit 20 is configured to generate a display image (i.e., the image that will be the basis for the display image PIC) on the liquid crystal panel 22 by illuminating the liquid crystal panel 22 with a backlight from its rear side.

[0048] A unit mounting section 52d for mounting the image generation unit 20 is formed in the lower wall portion 52b of the first housing 52. A rectangular opening 52e, which is slightly larger than the outer shape of the liquid crystal panel 22, is formed in this unit mounting section 52d.

[0049] The image generation unit 20 is fixed to the lower wall portion 52b of the first housing 52 by screws or the like, with the liquid crystal panel 22 positioned so that it fits into the opening 52e of the unit mounting portion 52d.

[0050] The first reflector 30 is positioned diagonally above and behind the image generation unit 20 and is configured to reflect the light emitted from the image generation unit 20 forward.

[0051] The first reflector 30 is configured as a saddle-type reflector, with its reflective surface 30a having a saddle-shaped curved surface. The reflective surface 30a of this first reflector 30 has a roughly rectangular outer shape that extends in the left-right direction when viewed from the front of the vehicle. Specifically, the horizontal cross-sectional shape of this reflective surface 30a is composed of a convex curve, and its vertical cross-sectional shape is composed of a concave curve.

[0052] The first reflector 30 has flange portions 32 formed on both the left and right ends of its reflective surface 30a, and is fixed to the first housing 52 at these left and right pair of flange portions 32.

[0053] Specifically, each flange portion 32 includes a side wall portion 32A formed to extend rearward along a vertical plane from the side end of the reflective surface 30a, and a stepped portion 32B formed to extend laterally from the outer surface of the side wall portion 32A. The first reflector 30 is then fastened and fixed by screws 34 to a pair of left and right columnar projections 52f formed on the lower wall portion 52b of the first housing 52, with the left and right stepped portions 32B positioned by pins 52g.

[0054] As shown in Figures 3 and 4, the second reflector 40 is positioned in front of the first reflector 30. This second reflector 40 is configured to reflect the light emitted from the image generation unit 20, which has been reflected by the first reflector 30, upwards.

[0055] The second reflector 40 is a concave mirror, and the surface shape of its reflective surface 40a is a substantially spherical concave curved surface. The reflective surface 40a of the second reflector 40 has a rectangular outer shape that extends in the left-right direction when viewed from the front of the vehicle. The reflective surface 40a of the second reflector 40 is formed to be larger in size than the reflective surface 30a of the first reflector 30, and is formed to have a larger aspect ratio (i.e., a more horizontally elongated shape) than the reflective surface 30a of the first reflector 30.

[0056] Thus, the reflective surface 40a of the second reflector 40 is curved significantly in the direction of the image that the driver 2 is to see, and is formed with a larger aspect ratio than the reflective surface 30a of the first reflector 30. However, since the first reflector 30 is configured as a saddle-shaped reflector, the reflected light from its reflective surface 30a has a small vertical spread and a large horizontal spread, which allows it to efficiently enter the reflective surface 40a of the second reflector 40.

[0057] The lower wall portion 52b of the first housing 52 is formed at a higher position in the surrounding area than the portion where the unit mounting portion 52d is formed and the portion located below the reflective surfaces 30a, 40a of the first and second reflectors 30, 40.

[0058] As shown in Figure 3, the second housing 54 has a light-shielding piece 54c that covers the peripheral area of ​​the reflective surface 30a of the first reflector 30. This light-shielding piece 54c is formed to extend in a plate shape diagonally downward and forward from the rear edge of the opening 54a in the second housing 54.

[0059] In the image illumination device 10, sunlight S that enters the vehicle interior through the front windshield 102 may enter the internal space 12 of the housing 50 through the light-transmitting cover 60. However, the light-shielding effect of the light-shielding piece 54c prevents this sunlight S from reaching the peripheral area of ​​the reflective surface 30a of the first reflector 30.

[0060] As shown in Figures 4 and 5, the second reflector 40 is supported by the first housing 52 so as to be rotatable around an axis Ax that extends in the left-right direction near the front of the second reflector 40. This configuration allows the second reflector 40 to be angle-adjusted to accurately direct the reflected light from the first reflector 30 onto the image display unit 102A of the front window 102.

[0061] As shown in Figure 3, this angle adjustment is performed within a relatively small angle range indicated by the dashed and dotted lines under normal use conditions. However, when not in use, the second reflector 40 rotates significantly to the rearward position indicated by the double dotted line, so that even if sunlight S is reflected by the second reflector 40, it does not reach the first reflector 30.

[0062] As shown in Figures 4 and 5, a pair of left and right plate-shaped flange portions 42 extending forward along the vertical plane are formed at both the left and right ends on the back side of the reflective surface 40a of the second reflector 40. First and second shaft portions 44A and 44B are formed on these left and right plate-shaped flange portions 42, extending in both left and right directions (i.e., away from the reflective surface 40a) along the axis Ax.

[0063] The first and second shaft portions 44A and 44B are both formed in a cylindrical shape. The second shaft portion 44B, located on the right side (left side when viewed from the front of the device), is shorter than the first shaft portion 44A, located on the left side, and the base end portion 46B of the lever member 46 is fixed to its tip surface. This base end portion 46B is formed to extend cylindrically coaxially with the second shaft portion 44B, and its outer diameter is set to the same value as that of the second shaft portion 44B.

[0064] The lever member 46 has an arm portion 46A extending rearward from its base end portion 46B, and its tip portion 46C is connected to the linear output shaft 72 of the actuator 70 for rotating the second reflector 40 around the axis Ax.

[0065] The actuator 70 is fixed to the lower wall portion 52b of the first housing 52 on its lower side, and its linear output shaft 72 is formed to extend upward into the internal space 12 of the housing 50.

[0066] The peripheral wall portion 52c of the first housing 52 is formed with a bearing portion 52h that supports the first shaft portion 44A from below, and a bearing portion 52j that supports the base end portion 46B of the lever member 46 from below.

[0067] The bearing portion 52h is formed on the inner surface of the left region of the peripheral wall portion 52c of the first housing 52, and the bearing portion 52j is formed on the inner surface of the right region of the peripheral wall portion 52c of the first housing 52. The upper surfaces of each bearing portion 52h and 52j are formed in a substantially U-shape, and their lower regions consist of a semi-cylindrical surface having an inner diameter that is substantially the same as the outer diameter of the first shaft portion 44A and the base end portion 46B of the lever member 46, respectively.

[0068] A tab 46D is formed at the base end 46B of the lever member 46, projecting downward, and a pair of left and right clamping portions 52k are formed on the lower wall portion 52b of the first housing 52, projecting upward. The tab 46D is formed to extend along a vertical plane extending in the front-rear direction, and the pair of left and right clamping portions 52k are formed to be located on both the left and right sides of the tab 46D. The second reflector 40 is positioned in the left-right direction relative to the first housing 52 by the engagement of the tab 46D and the pair of left and right clamping portions 52k.

[0069] The first shaft portion 44A and the base end portion 46B of the lever member 46 are supported by a pair of left and right bearing portions 52h and 52j, and their outer circumferential surfaces are elastically pressed by a pair of left and right pressing members 80 attached to the first housing 52, thereby positioning them in the vertical direction.

[0070] The left and right pairs of pressing members 80 are both leaf springs and have the same configuration. Therefore, the specific configuration of the pressing member 80 located on the right bearing portion 52j will be described below.

[0071] Figure 6 is a cross-sectional view taken along line VI-VI in Figure 5. Figure 7 is a detailed view of section VII in Figure 5.

[0072] As shown in Figures 6 and 7, the pressing member 80 comprises a base portion 82 and a spring piece portion 84. The base portion 82 is fastened and fixed to the first housing 52 by screws 92 at two locations, front and rear, and the spring piece portion 84 is configured to elastically press the base end portion 46B of the lever member 46 from above.

[0073] The base portion 82 comprises a horizontal portion 82A extending in the front-rear direction along a horizontal plane, and a pair of left and right vertical portions 82B extending upward from both left and right edges of the horizontal portion 82A. An opening 82Aa extending in the front-rear direction is formed in the horizontal portion 82A. This opening 82Aa has a substantially rectangular shape in a plan view extending in the front-rear direction. The spring piece portion 84 is formed inside this opening 82Aa so as to extend in an arc shape upward toward the rear from the front end of the base portion 82.

[0074] A plate cam portion 46E is formed at the base end portion 46B of the lever member 46, in the portion located below the spring piece portion 84 of the pressing member 80. This plate cam portion 46E has an oval surface shape formed to be in contact with the base end portion 46B in a side view, and is formed to bulge outwards diagonally upward and backward from the base end portion 46B.

[0075] The pressing member 80 is configured to elastically press the plate cam portion 46E downward by having its spring piece 84 contact the outer circumferential surface of the plate cam portion 46E from above.

[0076] In this case, within the angular range in which the second reflector 40 rotates in the normal operating state of the image illumination device 10 (i.e., within the small angular range shown by the dashed and dotted lines in Figure 6), the pressing member 80 is elastically displaced upward by the contact of its spring portion 84 with the outer circumferential surface of the plate cam portion 46E. As a result, an elastic reaction force acting on the plate cam portion 46E in the direction that rotates the second reflector 40 backward is always present, and the second reflector 40 is maintained at an accurate angular position without any play in its rotational direction. On the other hand, when the image illumination device 10 is not in use, the second reflector 40 rotates significantly backward to the position shown by the dotted line in Figure 6, and consequently, the plate cam portion 46E also rotates significantly backward to the position shown by the dotted line in Figure 6. As a result, the spring portion 84 of the pressing member 80 is no longer elastically displaced upward by contact with the outer circumferential surface of the plate cam portion 46E.

[0077] Next, the operation of this embodiment will be described.

[0078] In this embodiment, the image illumination device 10 has a configuration in which a second reflector 40 for reflecting light emitted from the image generation unit 20 toward the image display unit 102A is supported in a housing 50 that houses it so as to be rotatable around an axis Ax extending in the left-right direction (required direction). Therefore, the height position of the display image PIC can be adjusted according to the driver's height and preferences.

[0079] Furthermore, in this embodiment, a first shaft portion 44A (shaft member) extending in the axial direction Ax is formed at the left end of the second reflector 40, and a second shaft portion 44B extending in the axial direction Ax is formed at the right end of the second reflector 40, with the base end portion 46B (shaft member) of the lever member 46 coaxially fixed to the tip surface of this second shaft portion 44B. On the other hand, a pair of left and right pressing members 80 that elastically press the outer circumferential surface of the first shaft portion 44A and the outer circumferential surface of the base end portion 46B of the lever member 46 are attached to the first housing 52 of the housing 52. As a result, the second reflector 40 can be reliably held in a predetermined position, thereby improving the positional accuracy of the second reflector 40.

[0080] Furthermore, a plate cam portion 46E is formed on the first shaft portion 44A and the base end portion 46B of the lever member 46 in the portion that is pressed by the pressing member 80. By having its outer circumferential surface contact the pressing member 80, the second reflector 40 can be held in a biased state in one direction (i.e., in the direction of rotation toward the rear), thereby further improving the positional accuracy of the second reflector 40.

[0081] Furthermore, in this embodiment, the pressing member 80 is made of a leaf spring, and the spring piece 84 is in contact with the outer circumferential surface of the leaf cam portion 46E, making it easy to securely hold the second reflector 40 in a predetermined position.

[0082] In the first embodiment described above, the second reflector 40 was described as being supported in the first housing 52 so as to be rotatable around an axis Ax extending in the left-right direction. However, it is also possible to configure it to be supported so as to be rotatable around an axis extending in a direction inclined in the front-back direction or up-down direction with respect to the left-right direction.

[0083] In the first embodiment described above, the image illumination device 10 was described as having first and second reflectors 30 and 40. However, it is also possible to have a configuration with only a single reflector (specifically, only the second reflector 40), and even when such a configuration is adopted, it is possible to obtain substantially the same effects as in the first embodiment.

[0084] In the first embodiment described above, the image display unit 102A was described as being set on the inner surface of the front windshield 102, but it is also possible to configure the image display unit with a light-transmitting plate or the like that is placed on the interior side of the front windshield 102.

[0085] In the first embodiment described above, the image projection device 10 was described as an in-vehicle head-up display, but it can also be used for other purposes.

[0086] Next, a second embodiment of the present invention will be described.

[0087] Figures 8 and 9 are similar to those in Figures 6 and 7, showing the main parts of the image irradiation device 110 according to this embodiment.

[0088] As shown in Figures 8 and 9, the basic configuration of the image illumination device 110 according to this embodiment is the same as that of the first embodiment described above, but the configuration for securely holding the second reflector 40 in a predetermined position differs in part from that of the first embodiment.

[0089] In other words, this embodiment differs from the first embodiment in that the second housing 154 of the housing 150 itself is equipped with a function for positioning the base end portion 146B of the lever member 146 (i.e., the shaft member fixed coaxially to the tip surface of the second shaft portion 44B of the second reflector 40) in the vertical direction.

[0090] Specifically, the second housing 154 has a vertical rib 154d that extends in the front-rear direction, projecting downward from the lower surface of its outer peripheral flange portion 154b, and a rectangular recess 154e is formed in this vertical rib 154d. A pressing piece 154f is formed on the vertical rib 154d, extending in a cantilevered manner from the front side of the rectangular recess 154e towards the rear along the lower edge of the vertical rib 154d. The thickness of this pressing piece 154f in the vertical direction is smaller than the thickness of the vertical rib 154d, thereby allowing it to bend and deform in the vertical direction.

[0091] In the assembly process of the housing 150, when the outer peripheral flange portion 154b of the second housing 154 abuts against the upper end opening 152a of the first housing 152, the pressing piece 154f of the second housing 154 abuts against the base end portion 146B of the lever member 146, which is supported by the bearing portion 152j of the first housing 152, from above and elastically presses against it, thereby positioning the base end portion 146B in the vertical direction.

[0092] A similar positioning structure is also provided for the first axial portion 44A (not shown) of the second reflector 40.

[0093] Even when adopting the configuration of this embodiment, substantially the same effects and advantages as those of the first embodiment can be obtained.

[0094] In other words, in this embodiment, a pressing piece 154f is integrally formed on the second housing 154, which elastically presses the outer circumferential surface of the base end portion 146B (shaft member) of the lever member 146 supported by the bearing portion 152j of the first housing 152. As a result, the base end portion 146B of the lever member 146 can be reliably held in a predetermined position, thereby improving the positional accuracy of the second reflector 40.

[0095] Moreover, this can be achieved through a predetermined operation of assembling the first housing 152 and the second housing 154, thereby enabling the image irradiation device 110 to have an inexpensive configuration.

[0096] Next, a third embodiment of the present invention will be described.

[0097] Figure 10 is a diagram similar to Figure 6, showing the main parts of the image irradiation device 210 according to this embodiment. Figure 11 is a view in the direction of arrow XI in Figure 10.

[0098] As shown in Figures 10 and 11, the basic configuration of the image illumination device 210 according to this embodiment is the same as that of the first embodiment described above, but the configuration of the second reflector 240 and its mounting structure to the first housing 252 differ in some respects from that of the first embodiment.

[0099] In other words, in this embodiment, the first housing 252 is provided with a support bracket 290 having a shaft portion 290A that extends left and right along the axis Ax. In this embodiment, the plate-shaped flange portion 242 formed on the side end of the second reflector 240 is formed with a wider vertical width than in the first embodiment, and its tip surface 242a is formed in a planar shape that faces diagonally downward and forward. A U-shaped recess 242b is formed on this tip surface 242a that engages with the shaft portion 290A of the support bracket 290.

[0100] The second reflector 240 is equipped with a pair of plate-shaped flange portions 242 on the left and right sides, and the support bracket 290 is equipped with a pair of shaft portions 290A on the left and right sides.

[0101] Furthermore, the second reflector 240 in this embodiment is connected to an actuator via a lever member in a part not shown.

[0102] Figure 12 is a diagram similar to Figure 10, showing the main components of the image irradiation device 210 according to this embodiment in an disassembled state.

[0103] As shown in Figure 12, a pressing member 280 is attached to the plate-shaped flange portion 242 of the second reflector 240, which elastically presses against the outer circumferential surface of the shaft portion 290A of the support bracket 290, which is engaged with the recess 242b of the flange portion 242.

[0104] The support bracket 290 is provided with a plate-shaped connecting portion 290B that extends in the left-right direction, connecting a pair of left and right shaft portions 290A. At both ends of this plate-shaped connecting portion 290B, a pair of left and right flange portions 290C are formed in a flat plate shape, facing diagonally upward and backward. The pair of left and right shaft portions 290A are formed on the outer surfaces of these pairs of left and right flange portions 290C, and a large-diameter portion 290D, which has a larger diameter than the shaft portion 290A, is formed at their tip.

[0105] The pressing member 280 has the same configuration as the pressing member 80 of the first embodiment described above. The pressing member 280 is fastened to the plate-shaped flange portion 242 of the second reflecting mirror 240 by screws 292 at two locations, upper and lower, with its base portion 282 in contact with the front end surface 242a of the plate-shaped flange portion 242. The pressing member 280 is configured to elastically press the shaft portion 290A of the support bracket 290 from diagonally downward and forward by its spring piece portion 284.

[0106] The support bracket 290 is fixed to the first housing 252 at its plate-shaped connecting portion 290B. Specifically, the first housing 252 is formed as an inclined portion 252b1, where a part of its lower wall portion 252b extends diagonally upward and forward. The support bracket 290 is fastened and fixed to the first housing 252 by screws 294 at two locations, upper and lower, on both its left and right ends, with its plate-shaped connecting portion 290B in contact with the inclined portion 252b1.

[0107] Even when adopting the configuration of this embodiment, substantially the same effects and advantages as those of the first embodiment can be obtained.

[0108] In this embodiment, a support bracket 290 having a shaft portion 290A (shaft member) extending in the left-right direction (required direction) is fixed to the first housing 252 by screw fastening, while a plate-shaped flange portion 242 extending in a direction intersecting the axis Ax is formed on the side end of the second reflector 240, and a recess 242b that engages with the shaft portion 290A of the support bracket 290 is formed on the tip surface 242a of this plate-shaped flange portion 242, and a pressing member 280 that elastically presses the outer circumferential surface of the shaft portion 290A that is engaged with the recess 242b is attached to this plate-shaped flange portion 242, so that the second reflector 240 can be reliably held in a predetermined position, thereby improving the positional accuracy of the second reflector 240.

[0109] Furthermore, by configuring the shaft portion 290A of the support bracket 290 to engage with the recess 242b formed in the plate-shaped flange portion 242 of the second reflector 240, the size of the second reflector 240 can be reduced in the left-right direction, thereby making the image illumination device 210 more compact.

[0110] Next, a fourth embodiment of the present invention will be described.

[0111] Figure 13 is a diagram similar to Figure 6, showing the main parts of the image irradiation device 310 according to this embodiment.

[0112] As shown in Figure 13, the basic configuration of the image illumination device 310 according to this embodiment is the same as that of the first embodiment described above, but the configuration for securely holding the second reflector 340 in a predetermined position differs in part from that of the first embodiment.

[0113] In other words, in this embodiment, the second reflector 340 is supported so as to be rotatable around an axis Ax extending in the left-right direction relative to the first housing 352, by fitting metal pivot members 394, which are fixed to two locations on the left and right of the first housing 352, with resin bearing members 392, which are attached to two locations on the left and right of the second reflector 340.

[0114] Specifically, a projection 344 is formed on the outer surface of a plate-shaped flange portion 342 formed at the side end of the second reflector 340. This projection has a roughly C-shaped cross-section that opens diagonally downward and forward, and extends laterally. The bearing member 392 is inserted from the side and engages with this projection 344. The bearing member 392 has a spherical recess 392a, and an outer peripheral flange portion 392b is formed on its outer peripheral surface for engaging with the projection 344.

[0115] On the other hand, the first housing 352 has a portion of its lower wall 352b that is formed as an inclined portion 352b1 that extends diagonally upward and forward. A pivot member 394 that extends diagonally upward and backward is screw-fastened to this inclined portion 352b1 at its base end. This pivot member 394 has a spherical tip portion 394a, and this spherical tip portion 394a is press-fitted into the spherical recess 392a of the bearing member 392, so that the spherical tip portion 394a fits into the spherical recess 392a.

[0116] Note that while Figure 13 shows the fitting structure on the right side of the second reflector 340, the fitting structure on the left side is the same.

[0117] Figure 14 is a diagram similar to Figure 13, showing the main components of the image irradiation device 310 according to this embodiment in an disassembled state.

[0118] As shown in Figure 14, the bearing member 392 has multiple slits 392c formed on its peripheral wall. This allows the spherical tip 394a of the pivot member 394 to be easily press-fitted into the spherical recess 392a of the bearing member 392, and ensures that the fitted state between the spherical tip 394a and the spherical recess 392a is reliably maintained after press-fitting.

[0119] In this embodiment, the second reflector 340 is connected to the actuator via a lever member in a part not shown.

[0120] Even when adopting the configuration of this embodiment, substantially the same effects and advantages as those of the first embodiment can be obtained.

[0121] In other words, in this embodiment, bearing members 392 having spherical recesses 392a are mounted on the left and right sides of the second reflector 340 (two locations in the required direction), while pivot members 394 having spherical tip portions 394a formed to fit with the spherical recesses 392a are provided on the left and right sides of the first housing 352. Therefore, by fitting these pair of spherical recesses 392a and pair of spherical tip portions 394a, the second reflector 340 is supported so as to be rotatable around axis Ax relative to the first housing 352, and its positional accuracy can be improved.

[0122] Moreover, this can be achieved with a simple configuration consisting only of fitting together a pair of spherical recesses 392a and a pair of spherical tip portions 394a, thereby enabling the image irradiation device 310 to have an inexpensive configuration.

[0123] Next, a modified example of the fourth embodiment described above will be explained.

[0124] Figure 15 is a diagram similar to Figure 13, showing the main parts of the image irradiation device 410 according to this modified example.

[0125] As shown in Figure 15, the image illumination device 410 according to this modified example has the same basic configuration as the fourth embodiment described above, but differs from the fourth embodiment in that a pair of left and right bearing members 492 are provided at two locations on the left and right of the first housing 452, and a pair of left and right pivot members 448 are provided at two locations on the left and right of the second reflector 440.

[0126] In this modified example, the pivot member 448 is configured as part of the second reflector 440. That is, the pivot member 448 is formed to extend rearward from the tip surface of the plate-shaped flange portion 442 formed on the side end of the second reflector 440. On the other hand, the bearing member 492 in this modified example has the same configuration as the bearing member 392 of the fourth embodiment, and is positioned and fixed to the first housing 452 with its spherical recess 492a facing forward.

[0127] The first housing 452 is formed as a shelf-like portion 452b1 in which a part of its lower wall portion 452b is displaced upward, and a groove portion 452b2 is formed at its rear end that engages with the outer peripheral flange portion 492b of the bearing member 492. The bearing member 492 has the lower part of its outer peripheral flange portion 492b inserted into the groove portion 452b2, and an engaging fitting 494 having an engaging recess 494a that engages with the upper part of its outer peripheral flange portion 492b is pressed against the bearing member 492 from above, and the engaging fitting 494 is tightened to the shelf-like portion 452b1 of the first housing 452 with a screw 496, thereby positioning and fixing the bearing member 492 relative to the first housing 452.

[0128] Even when this modified configuration is adopted, the fitting of the spherical tip portion 448a of the pivot member 448 and the spherical recess 492a of the bearing member 492 allows the second reflector 440 to be supported so as to be rotatable around axis Ax relative to the first housing 452, and its positional accuracy can be improved. This makes it possible to make the image illumination device 410 an inexpensive configuration.

[0129] In this modified example, the pivot member 448 is described as being part of the second reflector 440, but it is also possible to adopt a configuration in which the pivot member 448 is fixed to the second reflector 440 by screw fastening or the like. [Explanation of Symbols]

[0130] 2 drivers 10 Image irradiation device 12 Interior space 20 Image Generation Units 22 LCD panels 30 1st reflector 30a, 40a reflective surface 32 Flange section 32A Side wall part 32B Staircase 34, 92 screws 40 Second reflector 42 Plate-shaped flange portion 44A First shaft section 44B Second shaft section 46 Lever member 46A Arm section 46B Base end 46C Tip 46D Tab 46E Plate Cam Section 50 Housing 52 Housing 1 52a Top opening 52b Lower wall part 52c Peripheral wall part 52d Unit mounting section 52e, 54a, 82Aa opening 52f Columnar projection 52g pin 52h, 52j bearing part 52k clamping part 54 Second Housing 54b Outer flange portion 54c Light shielding piece 60 Translucent Cover 70 Actuators 72 Linear output shaft 80 Pressing member 82 Base part 82A Horizontal part 82B Vertical surface 84 Spring piece 100 vehicles 102 Front windshield 102A Image display section 104 Steering Wheel 110 Image irradiation device 146 Lever member 146B Base end (shaft member) 150 Housing 152 Housing 1 152a Top opening 152j bearing part 154 Second Housing 154b Outer flange section 154d Vertical Rib 154e Rectangular recess 154f Pressing piece 210 Image irradiation device 240 Second reflector 242 Plate-shaped flange portion 242a Tip surface 242b recess 252 Housing 1 252b Lower wall part 252b1 Slope section 280 Pressing member 282 Base part 284 Spring piece 290 Support bracket 290A Shaft (shaft member) 290B Plate-shaped connecting part 290C Flange section 290D Large diameter section 292, 294 screws 310, 410 Image irradiation device 340, 440 2nd reflector 342, 442 Plate-shaped flange portion 344 Protrusion 352, 452 1st Housing 352b, 452b lower wall part 352b1 Slope 392, 492 Bearing components 392a, 492a Spherical recess 392b, 492b Outer flange section 392c Slit 394, 448 Pivot members 394a, 448a spherical tip 452b1 Shelf 452b2 Groove 494 Engagement fittings 494a Engagement recess 496 screws Ax axis PIC display image R optical path S Sunlight

Claims

1. In an image projection device configured to display an image on an image display unit, The system comprises an image generation unit that generates the above-mentioned display image, a reflector that reflects the light emitted from the image generation unit toward the image display unit, and a housing that accommodates the reflector. The above-mentioned reflector is supported in the housing so as to be rotatable about an axis extending in the required direction. A shaft member extending in the required direction is provided at the side end of the above-mentioned reflecting mirror. The housing has a bearing portion formed therein for supporting the shaft member. A pressing member is attached to the housing above, which elastically presses against the outer circumferential surface of the shaft member supported by the bearing portion above. The image irradiation device is characterized in that the shaft member has a plate-cam shaped outer surface with respect to the portion pressed by the pressing member, with respect to the axis.

2. In an image projection device configured to display an image on an image display unit, The system comprises an image generation unit that generates the above-mentioned display image, a reflector that reflects the light emitted from the image generation unit toward the image display unit, and a housing that accommodates the reflector. The above-mentioned reflector is supported in the housing so as to be rotatable about an axis extending in the required direction. A shaft member extending in the required direction is provided at the side end of the above-mentioned reflecting mirror. The above housing has a configuration in which a first housing and a second housing are assembled. The first housing described above has a bearing portion formed therein for supporting the shaft member. An image irradiation device characterized in that a pressing piece is integrally formed in the second housing above, which elastically presses against the outer circumferential surface of the shaft member supported by the bearing portion.

3. In an image projection device configured to display an image on an image display unit, The system comprises an image generation unit that generates the above-mentioned display image, a reflector that reflects the light emitted from the image generation unit toward the image display unit, and a housing that accommodates the reflector. The above-mentioned reflector is supported in the housing so as to be rotatable about an axis extending in the required direction. The housing is provided with a shaft member extending in the required direction. A plate-shaped flange portion is formed at the side end of the above-mentioned reflector, extending in a direction intersecting the required direction. A recess is formed on the tip surface of the plate-shaped flange portion, which engages with the shaft member. An image irradiation device characterized in that a pressing member is attached to the plate-shaped flange portion, which elastically presses the outer circumferential surface of the shaft member that is engaged with the recess.

4. In an image projection device configured to display an image on an image display unit, The system comprises an image generation unit that generates the above-mentioned display image, a reflector that reflects the light emitted from the image generation unit toward the image display unit, and a housing that accommodates the reflector. The above-mentioned reflector is supported in the housing so as to be rotatable about an axis extending in the required direction. A bearing member having a spherical recess is provided at two locations in the required direction on either the reflector or the housing. An image irradiation device characterized in that pivot members having spherical tip portions formed to fit with the spherical recesses are provided at two locations in the required direction on either the reflecting mirror or the housing.

Images