JP7377443B2 - power transmission device - Google Patents

Description

The present invention relates to a power transmission device used, for example, in a head-up display device.

Conventionally, in this type of power transmission device, a stepping motor (drive member) is used to adjust the angular position of a concave mirror included in a head-up display device for a vehicle, as described in Patent Document 1 below, for example. There is a known device that adjusts the angular position of a concave mirror by driving it.

Here, the above-mentioned head-up display device is mainly composed of a reflector that reflects display light emitted from a display device, and a housing that houses the display device and the reflector, and the display light is reflected by a concave mirror provided in the reflector. The display light is irradiated onto the windshield of the vehicle, and the display image obtained by this irradiation is made visible to the vehicle user.

In this case, the reflector includes a concave mirror (reflecting member) that reflects the display light from the display, a resin mirror holder (holding member) that holds this concave mirror, and a mirror holder that faces outward from the mirror holder. A power transmission device capable of rotating a mirror holder about a predetermined rotational axis by transmitting power to a protruding piece that is a partially protruding power transmitting part, and adjusting the angular position of the mirror holder. Equipped with

The power transmission device includes a stepping motor and a rotating shaft extending from the stepping motor, and a driving means having a lead screw portion, which is a threaded groove, on the circumferential surface of the rotating shaft, and mainly has a function of fixedly supporting the stepping motor. a metal support body, a metal nut fixed to engage with the lead screw part, a guide shaft fitted to the support body so as to be parallel to the lead screw part, and a base part. A pair of abutting surfaces that abut each side of the nut are formed on the base, and a pair of hemispherical protrusions that make point contact with the protruding piece of the mirror holder are formed on a pair of opposing walls that protrude forward of the base. and power transmission members formed respectively.

In the power transmission device configured in this way, when the lead screw portion is rotationally driven as the stepping motor is driven, the nut screwed onto the lead screw portion is rotated in the axial direction of the lead screw portion due to the rotation of the lead screw portion. , and in synchronization with the reciprocating movement of the nut, for example, one of the two side surfaces of the nut is brought into contact with one of the pair of abutting surfaces, the side that abuts the one side surface. Thrust acts on the surface.

Due to the action of this thrust, the power transmission member moves along the axial direction (reciprocating movement) in synchronization with the reciprocating movement of the nut while being guided by the guide shaft. Then, as the power transmission member moves, the protruding piece that is in point contact with the pair of projections provided on the power transmission member receives a power that rotates the mirror holder about the rotation axis. communicated.

In other words, this means that the mirror holder and the concave mirror held by the mirror holder are rotated by a predetermined angle about the rotation axis by power transmission to the protruding piece. By angularly moving the concave mirror in this way, the projection direction of the display light onto the windshield is adjusted, and accordingly, the position of the display image visible to the vehicle user is moved in the vertical direction of the windshield. becomes possible.

JP2009-73461A

By the way, in the case of the power transmission device used in the head-up display device described in Patent Document 1, the projecting piece of the mirror holder is sandwiched between a pair of projections provided on the power transmission member. Generally, there are dimensional tolerances in the dimensions of each part of the power transmission member and the mirror holder. It is conceivable that a slight clearance may occur between the protrusion (the protrusion) and the protrusion piece provided on the mirror holder.

Then, due to this minute clearance, the mirror holder (that is, the concave mirror held in the mirror holder) is likely to tilt in a rattling manner, resulting in blurring of the displayed image seen by the vehicle user through the windshield. There is a possibility that this may occur.
SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, it is an object of the present invention to provide a power transmission device that is free from the possibility of image blurring of a displayed image.

The present invention provides a lead screw portion that is rotationally driven as a drive member is driven, and a power transmission member that moves along the axial direction of the lead screw portion due to the rotation of the lead screw portion and transmits power to a power transmission portion. In the power transmission device, the power transmission member has a pair of walls facing each other with the power transmission part in between, and one wall part of the pair of walls has the power transmission part. a first abutting portion in which the protruding portion protrudes toward the part side, an elastic member is provided on the other wall portion of the pair of wall portions, and the protruding portion and the power transmitting portion abut against each other; and a second abutting portion where the elastic member and the power transmitting portion abut are not located on an imaginary line extending parallel to the axial direction.

According to the present invention, it is possible to provide a power transmission device that can achieve the intended purpose and is free from the possibility of image blurring of a displayed image.

1 is a schematic diagram of a head-up display device according to an embodiment of the present invention. FIG. 3 is a cross-sectional view of the head-up display device according to the same embodiment. It is a perspective view which shows the 2nd reflector by the same embodiment. It is a sectional view showing the second reflector and the required part of the housing by the same embodiment (hatching is omitted). It is a perspective view which shows each part of the position adjustment means and a part of holding member by the same embodiment. FIG. 3 is a cross-sectional view showing the positional relationship between the drive means, the moving member, and the power transmission member in the position adjustment means according to the same embodiment. FIG. 2 is an enlarged sectional view of a main part showing a part of the power transmission member and a part of the holding member according to the same embodiment (hatching is omitted). FIG. 7 is an enlarged cross-sectional view of a main part showing a part of a power transmission member and a part of a holding member according to a modification of the same embodiment (hatching is omitted).

Hereinafter, an embodiment in which the power transmission device of the present invention is applied to a second reflector included in a head-up display device for a vehicle will be described based on FIGS. 1 to 7.

As shown in FIG. 1, the head-up display device displays display light L projected by a display device 12, which is a display unit disposed inside an instrument panel 11 of a vehicle 10, on a windshield 13 of the vehicle 10, which is a projection member. is reflected in the direction of the driver (user) 14 to display a virtual image V. In other words, the head-up display device emits (projects) display light L emitted from a liquid crystal display device (described later) of the display device 12 onto the windshield 13 (the projection member), and displays a display image ( The virtual image) V is made visible to the user 14. This allows the user 14 to observe the virtual image V superimposed on the scenery.

The display device 12 mainly includes a liquid crystal display 20, a first reflector 30, a second reflector 40, and a housing 50, as shown in FIG.

The liquid crystal display 20 includes a light source 21 made of a light emitting diode mounted on a wiring board R, and a light source 21 located in front of (directly above) the light source 21 so as to transmit illumination light from the light source 21 and form display light L. It is mainly composed of a TFT type liquid crystal display element (display element) 22 located therein. This means that the light source 21 is disposed behind (directly below) the liquid crystal display element 22, and the liquid crystal display element 22 displays predetermined information (information to be displayed, which will be described later) using the light emitted from the light source 21. It means.

In this case, the liquid crystal display 20 is provided in the housing 50 such that the surface on the emission side of the display light L faces a cold mirror (described later) of the first reflector 30, and the optical axis of the display light L is arranged in the cold mirror. It is fixed and held in a position and direction that intersects with the mirror.

Further, the liquid crystal display element 22 emits and displays information (for example, vehicle speed and engine rotational speed) to be displayed by an element drive circuit (not shown) in the form of numerical values or the like. The liquid crystal display 20 outputs display light L consisting of light in the visible wavelength range, and for example, a light source 21 that emits red light (mainly in the emission wavelength range of 610 to 640 nm) can be applied. It goes without saying that the information to be displayed is not limited to the speed of the vehicle or the number of engine revolutions, but can be displayed in any other form.

The first reflector 30 includes a cold mirror 31 and a mounting member 32 for mounting and fixing the cold mirror 31 using a predetermined mounting means.

The cold mirror 31 includes a substantially rectangular glass substrate 31a and a first reflective layer 31b formed on one surface of the glass substrate 31a (the surface facing a concave mirror of the second reflector 40, which will be described later). The first reflective layer 31b is composed of a multilayer interference film having different thicknesses, and is formed by a method such as vapor deposition. Further, the cold mirror 31 is arranged in an inclined state at a position where it reflects the display light L emitted by the liquid crystal display 20 toward the second reflector 40 (the concave mirror).

Note that the cold mirror 31 reflects light in the visible wavelength range (450 to 750 nm) including the emission wavelength range of the liquid crystal display 20 with a high reflectance (for example, 80% or more), and reflects light outside the visible wavelength range with a low reflectance. It reflects with reflectance. In this case, the cold mirror 31 is one that reflects light in the infrared wavelength range (infrared rays or heat rays of sunlight) other than the visible wavelength range with a low reflectance (for example, 15% or less). Note that the configuration is such that the light that is not reflected by the first reflective layer 31b is transmitted through the cold mirror 31.

Furthermore, in the case of the present embodiment, the cold mirror 31 and the liquid crystal display 20 are arranged in a position where they cannot be directly viewed from the later-described translucent cover of the housing 50, and the cold mirror 31 and the liquid crystal display 20 are disposed at a position where they cannot be directly viewed from the translucent cover, which will be described later, of the housing 50. The structure is such that it does not hit directly. The mounting member 32 is made of, for example, a black synthetic resin material, and is fixed to the housing 50 using an appropriate fixing means.

As shown in FIGS. 2 to 4, the second reflector 40 includes a concave mirror (reflection member) 41 that reflects the display light L from the cold mirror 31 (that is, the display element 22), and a mirror holder that holds the concave mirror 41. The holding member 42 is provided with a position adjusting means 43 for adjusting the angular position (disposition position) of the holding member 42.

The concave mirror 41 is formed by depositing a second reflective layer 41a on a resin substrate made of polycarbonate and having a concave surface. This concave mirror 41 is disposed in an inclined state at a position where its second reflective layer 41a faces the cold mirror 31 and the light-transmitting cover, and can be seen from the light-transmitting cover.

Further, the concave mirror 41 magnifies the display light L from the cold mirror 31 and reflects (projects) it toward the translucent cover (windshield 13 of the vehicle 10). This means that the concave mirror 41 magnifies the display light L reflected by the cold mirror 31 and projects the magnified display light L onto the windshield 13 through the translucent cover.

The holding member 42 is made of a metal material (or a synthetic resin material) and includes a substantially cylindrical shaft portion 42a that is pivotally supported by a bearing portion (not shown) provided in the housing 50. Further, the holding member 42 includes a holding portion 42b that is a wall portion for holding (supporting) the concave mirror 41. In this case, the concave mirror 41 is fixedly held to the holding part 42b with a double-sided adhesive tape (not shown) interposed between the concave mirror 41 and the holding part 42b. Further, the holding member 42 and the concave mirror 41 held therein are configured to be angularly movable (rotatable) around the rotation axis (predetermined rotation axis) RA, which is the central axis of the shaft portion 42a. There is.

Note that 42c is a protruding piece (protruding part) formed in a substantially L-shape below the concave mirror 41 from behind the concave mirror 41 toward the second reflective layer 41a side, and this protruding piece 42c is It has a first extension part 42d and a second extension part 42e as a driven power transmission part, and is integrally formed with the holding member 42.

In FIG. 4, the first extension portion 42d extends from a bottom surface portion 42f that constitutes the bottom wall of the holding portion 42b of the holding member 42 toward the second reflective layer 41a side (in other words, This is a thin plate-like wall portion (extending substantially along the axial direction of the screw portion).

Further, the second extension part 42e, which is a power transmission part, is continuous with the first extension part 42d so as to hang downward (toward the lead screw part side) from the tip of the first extension part 42d. This is a thin plate-like standing wall section. The second extension 42e is arranged so that both side surfaces 42g and 42h (see FIG. 4) are in point contact with a protrusion and a leaf spring provided in a position adjusting means, which will be described later. It is held between the In the following description, the side surface 42g is referred to as one side surface among the both side surfaces 42g and 42h, and the side surface 42h is also referred to as the other side surface.

The position adjusting means 43 is mainly composed of a driving means 61, a support body 62, a nut 63, a guide shaft 64, a power transmission member 65, and a vibration isolating member 66, as shown in FIGS. 3 to 5. , is used to rotate the holding member 42 around the rotation axis RA and adjust the angular position of the holding member 42 (concave mirror 41) (in other words, adjust the projection direction of the display light L).

The driving means 61 includes a stepping motor (driving member) 61a that generates rotational driving force when energized, and a rotating shaft 61b extending from the stepping motor 61a. The rotating shaft 61b includes a lead screw portion 61c, which is a thread groove formed in a spiral shape on its circumferential surface. The lead screw portion 61c (rotary shaft 61b) is configured to be rotationally driven by receiving the rotational driving force from the stepping motor 61a.

The support body 62 is a metal motor case that fixedly supports the stepping motor 61a in an immovable state, and is a generally plate having a substantially U-shaped cross section and disposed along the axial direction X of the lead screw portion 61c. It has a flat plate portion 62a having a shape, and a pair of first and second flange portions 62b and 62c, which are formed by bending both end portions of the flat plate portion 62a at approximately right angles.

The first flange portion 62b located on the stepping motor 61a side has a through hole 62d through which an end portion (distal end portion) 61d of the lead screw portion 61c passes, and a through hole 62d into which one end portion of the guide shaft 64 is fitted. One fitting hole 62e is formed. Note that the first flange portion 62b and a necessary portion of the stepping motor 61a are fixed to each other by appropriate fixing means, and thereby the stepping motor 61a is fixedly supported by the support body 62 in an immovable state.

On the other hand, on the side of the second flange part 62c that is paired with the first flange part 62b, there is a hole (not shown) corresponding to the through hole 62d, a hole corresponding to the first fitting hole 62e, and a hole (not shown) for the guide shaft 64. A second fitting hole 62f into which the other end is fitted is formed. Note that the bearing member G is mounted in the hole provided in the second flange portion 62c. A distal end portion 61e of the lead screw portion 61c located on the distal end side of the protruding portion that protrudes toward the bearing member G side through the through hole 62d is rotatably supported through the bearing member G.

Note that 62g and 62h are provided at positions corresponding to first and second screw holes (to be described later) of the vibration isolating member 66, and are screwed into threaded portions of screws S1 that pass through the first and second screw holes. These are the first and second threaded parts for making the connection. The first and second threaded parts 62g and 62h are formed in a substantially cylindrical shape protruding from the surface side of the flat plate part 62a at both ends of the flat plate part 62a. 62g is provided near the first flange portion 62b, and a second threaded portion 62h is provided near the second flange portion 62c.

The nut 63 is screwed (engaged) at a predetermined location of the lead screw portion 61c on the rotating shaft 61b, and is moved over the lead screw portion 61c in the axial direction X of the lead screw portion 61c by the thrust given by the rotation of the lead screw portion 61c. move along. In this case, the nut 63 is configured to move (reciprocate) to the distal end 61e or distal end 61d of the lead screw portion 61c as the lead screw portion 61c is rotationally driven.

The guide shaft 64 is made of, for example, a metal material in the shape of an elongated column, and one end thereof is connected to the first fitting hole 62e of the support body 62 so as to be substantially parallel to the lead screw portion 61c (rotary shaft 61b). At the same time, the other end is fitted into the second fitting hole 62f of the support body 62.

The power transmission member 65 is formed of a synthetic resin material such as polyacetal, and includes a base portion 65a, a pair of wall portions 65c protruding upward from a surface portion 65b of the base portion 65a, and facing each other. 65d. Further, in this case, the power transmission member 65 has a function of moving along the axial direction X of the lead screw portion 61c by rotation of the lead screw portion 61c and transmitting power to the second extension portion 42e.

In the following description, of the pair of wall portions 65c and 65d that face each other with the second extension portion 42e in between, the opposing wall located on the distal end portion 61d side of the lead screw portion 61c will be referred to as one wall portion 65c. Among the wall portions 65c and 65d, the opposing wall located on the distal end portion 61e side of the lead screw portion 61c is defined as the other wall portion 65d.

The base portion 65a has an insertion portion 65e formed of a substantially circular through-hole shape through which the guide shaft 64 is inserted, and abutment ( A pair of first and second contact portions 65f and 65g that make surface contact (see FIG. 6) are formed. In this case, the first and second contact parts 65f and 65g are integrally formed with the base part 65a so as to partially sandwich the first and second side surfaces 63a and 63b of the nut 63.

In addition, in the nut 63, the surface on the first flange portion 62b side is referred to as a first side surface 63a, and the surface on the second flange portion 62c side is referred to as a second side surface 63b. Further, the first contact portion 65f and the first side surface 63a are in contact with each other, and the second contact portion 65g and the second side surface 63b are in contact with each other, so that the first and second contact portions 65f and 65g It is assumed that the nut 63 is sandwiched.

One wall portion 65c is provided with a substantially hemispherical protrusion 65h that protrudes toward one side surface 42g (second extension portion 42e side), and the other wall portion 65d is provided with a protrusion 65h on the other side surface 42h. A metal leaf spring 65i is provided as an elastic member for applying a pressing force (described later) to the second extension portion 42e (see FIG. 7).

Although details will be described later, when the second extension 42e is inserted between the protrusion 65h and the leaf spring 65i, the second extension 42e and the protrusion 65h are connected to the apex portion of the protrusion 65h. The structure is such that point contact is always made at the first contact portion T1. Note that the shape of the protrusion 65h may be any shape as long as it can make point contact with the one side surface 42g.

The leaf spring 65i includes, for example, a fixing portion F1 that is attached to the surface of the other wall portion 65d on the other side surface 42h side and is fixed to the other wall portion 65d using an appropriate fixing means so as to be in close contact with the other wall portion 65d, and this fixing portion An inclined portion F2 extending obliquely from the upper end side of F1 toward the other side surface 42h side, and a bent tip portion F3 slightly bent from the lower end side of this inclined portion F2 toward the fixed portion F1 side. has.

Here, when the second extension part 42e is inserted between the leaf spring 65i and the protrusion 65h under the condition that the leaf spring 65i is attached to the other wall part 65d, the leaf spring 65i is connected to the inclined part F2. With the bent end portion F3 being slightly elastically deformed toward the other wall portion 65d, the second extension portion 42e and come into contact with

Then, since a pressing force (elastic restoring force) acts on the leaf spring 65i toward the one wall portion 65c, the second extension portion 42e is always urged toward the projection portion 65h side, and the second extension portion 42e is always urged toward the projection portion 65h side. The extension portion 42e (one side surface 42g) and the protrusion portion 65h are always never separated. Accordingly, the second extension 42e and the protrusion 65h come into point contact at the first contact portion T1, and as a result, the second extension 42e is always in contact between the protrusion 65h and the leaf spring 65i. , it will be pinched.

At this time, the first contact portion T1 where the second extension portion 42e (one side surface 42g) and the protrusion 65h come into contact with each other, and the second extension portion 42e (the other side surface 42h) and the leaf spring 65i come into contact with each other. Focusing on the positional relationship with the second abutting portion T2, in this example, both the first abutting portion T1 and the second abutting portion T2 extend in parallel to the axial direction X of the lead screw portion 61c. A configuration in which the image sensor is not located on the line (virtual horizontal line) 70 is adopted.

For example, in FIG. 7, when the first contact portion T1 is located on the virtual line 70, the second contact portion T2 is not located on the virtual line 70 and is located below the virtual line 70. There is. In other words, this means that in the height direction of the pair of wall portions 65c and 65d (direction perpendicular to the axial direction This means that the second contact portion T2 is located below the first contact portion T1.

The vibration isolating member 66 is made of a soft synthetic resin material (for example, polypropylene resin) having a vibration damping function, and includes a substantially rectangular flat base portion 66a provided to correspond to the flat plate portion 62a of the support body 62. . The vibration isolating member 66 has a vibration damping function that damps vibrations generated when the stepping motor 61a is driven from the support body 62 to the housing 50.

Of the four corners of the base 66a of the vibration isolating member 66, a first corner C1 provided at a position corresponding to a first boss portion of the housing 50, which will be described later, has a first ear portion 66b. , are formed protruding from the sides of the base 66a so as to have substantially the same thickness as the base 66a. In addition, a second ear portion 66c is provided at a second corner portion C2, which is provided in a diagonal direction of the first corner portion C1 and at a position corresponding to a second boss portion of the housing 50, which will be described later. It is formed to protrude from the side of the base portion 66a so as to have substantially the same thickness as that of the base portion 66a.

In addition, 66d and 66e are provided so as to communicate with the first and second threaded portions 62g and 62h of the support body 62, respectively, and are through holes for passing the threaded portion of the screw S1 from the back side of the base portion 66a. The first and second screw holes 66d and 66e are located near the center of the base 66a, and the first screw hole 66d is located near the center of the base 66a. 62b side, and a second screw hole 66e is provided on the second flange portion 62c side.

The vibration isolating member 66 and the support body 62 are fixed by passing the threaded portion of the screw S1 from the back side of the base 66a into the first and second screw holes 66d and 66e, respectively, as shown in FIG. The required portions of the screw portions of the screw S1 passing through the screw holes 66d and 66e are screwed into the first and second screw portions 62g and 62h, respectively, thereby completing the process. Thereby, the support body 62 and the vibration isolating member 66 are fixed by the screw S1, which is the first fixing means.

In addition, 66f is provided so as to communicate with a third screw threaded part provided in the first boss part and will be described later, and is provided from a through hole for passing the threaded part of the screw S2 from the surface side of the base part 66a. This third screw hole 66f is formed at a predetermined location of the first ear portion 66b.

Similarly, 66g is a through hole provided in the second boss portion so as to communicate with a fourth screw threaded portion to be described later, and for passing the threaded portion of the screw S2 from the surface side of the base portion 66a. This fourth screw hole 66g is formed at a predetermined location of the second ear portion 66c.

The position adjusting means 43 configured in this manner causes the nut 63 engaged with the lead screw portion 61c to move in the axial direction X when the lead screw portion 61c is rotationally driven in response to the rotational driving force from the stepping motor 61a. Move back and forth along the route. For example, when the nut 63 is moving toward the first flange portion 62b, the first side surface 63a of the nut 63 has a first contact portion 65f in surface contact with the first flange portion 63a. A thrust force is applied to move the portion 62b toward the portion 62b.

Due to the action of this thrust, the power transmission member 65, guided by the guide shaft 64, moves in parallel along the axial direction X toward the first flange portion 62b in synchronization with the movement of the nut 63. Then, as the power transmission member 65 moves in parallel, power for rotating the holding member 42 is transmitted to the second extension 42e interposed between the protrusion 65h and the leaf spring 65i. . In other words, this means that the holding member 42 rotates in the direction of the arrow in FIG. 4 about the rotation axis RA due to power transmission to the second extension portion 42e.

Note that when the nut 63 moves not to the first flange part 62b side but to the second flange part 62c side, the power transmission member 65 moves in parallel to the second flange part 62c side, and thereby the second Needless to say, a power that causes the holding member 42 to rotate in a direction opposite to the arrow direction in FIG. 4 about the rotation axis RA acts on the extension portion 42e.

The housing 50 is made of aluminum die-casting, for example, and includes an upper case 51 and a lower case 52, both of which have a substantially concave cross section. 53 houses the liquid crystal display 20 (liquid crystal display element 22), the first reflector 30, and the second reflector 40 composed of a concave mirror 41, a holding member 42, and a position adjustment means 43 (see FIG. (see 2).

The upper case body 51 is formed with an opening window 51a that opens at the upper part (on the windshield 13 side of the vehicle 10) where the concave mirror 41 is disposed. A translucent cover 54, which is a translucent portion, is disposed to cover the area.

The light-transmitting cover 54 is formed of a light-transmitting synthetic resin material, and functions as a light-transmitting member through which the display light L reflected by the concave mirror 41 is transmitted. That is, the display light L reflected by the concave mirror 41 is projected onto the windshield 13 through the translucent cover 54 formed on the housing 50, thereby displaying the display image (virtual image) V.

On the other hand, at the bottom of the lower case body 52, as shown in FIG. provided.

Of these, the first boss portion 52a includes a third screw screw portion 52c for screwing the screw S2, and the third screw screw portion 52c is provided with a third screw screw portion 52c provided on the vibration isolating member 66. It communicates with the screw hole 66f. On the other hand, the second boss portion 52b includes a fourth threaded portion 52d for threading the screw S2, and the fourth threaded portion 52d is a fourth threaded portion 52d provided on the vibration isolating member 66. It communicates with hole 66g.

The housing 50 (each boss part 52a, 52b) and the vibration isolating member 66 are fixed by passing the threaded part of the screw S2 from the surface side of the base part 66a into the third and fourth screw holes 66f and 66g, respectively. Required portions of the threaded portions of the screws S2 passing through the respective screw holes 66f and 66g are screwed into the third and fourth screw threading portions 52c and 52d provided in the respective boss portions 52a and 52b, respectively. Complete with . Thereby, the housing 50 (each boss portion 52a, 52b) and the vibration isolating member 66 are fixed by the screw S2, which is the second fixing means.

As described above, in this embodiment, one wall 65c of the power transmission member 65 is provided with a protrusion 65h that projects toward the second extension 42e, and the other wall 65d of the power transmission member 65 is provided with a protrusion 65h that projects toward the second extension 42e. is provided with a leaf spring 65i, a first contact portion T1 where the projection 65h and the second extension 42e come into contact, and a second contact portion where the leaf spring 65i and the second extension 42e come into contact. T2 and T2 are not located on a virtual line 70 extending parallel to the axial direction X of the lead screw portion 61c.

Therefore, when the second extension part 42e is pressed toward one wall part 65c by the leaf spring 65i (the elastic return force), the second extension part 42e (projection piece 42c) and the projection part 65h always It touches and never leaves. This suppresses the occurrence of the minute clearance that is conventionally formed between the protrusion and the protrusion piece, and improves the reliability of fixing the second extension 42e held between the protrusion 65h and the leaf spring 65i. The holding member 42 does not shake when power is transmitted to the holding member 42 by the second extension 42e, and image blurring of the display image V that is visually recognized by the user 14 through the windshield 13 occurs. There will be no fear.

Note that the present invention is not limited to the above-described embodiments and drawings. It is possible to make changes (including deletion of components) to the embodiments and drawings as appropriate without changing the gist of the present invention.

For example, in the above-described embodiment, the second contact portion T2 is located lower than the first contact portion T1 in the height direction of the pair of wall portions 65c and 65d. It is sufficient that the contact portion T1 and the second contact portion T2 are not provided at the same height position in the height direction. For example, as a modification of this embodiment, as shown in FIG. It goes without saying that the second contact portion T2 may be located above the first contact portion T1 in the height direction as shown in FIG.

30 First reflector
40 Second reflector
41 Concave mirror (reflection member)
42 Holding member
42c protruding piece
42d First extension
42e Second extension part (driven power transmission part)
42g One side (one side)
42h Other side (other side)
43 Position adjustment means
61 Drive means
61a Stepping motor (drive member)
61c Lead screw part
62 Support
63 Nut
64 Guide shaft
65 Power transmission section
65a base
65c One wall
65d Other wall
65h protrusion
65i leaf spring (elastic member)
66 Vibration isolation member
70 Virtual line (virtual horizontal line)
L Display light
RA rotation axis
T1 First contact part
T2 Second contact part
X axis direction

Claims (1)

a lead screw portion that is rotationally driven as the driving member is driven;
A power transmission device comprising: a power transmission member that moves along the axial direction of the lead screw portion by rotation of the lead screw portion and transmits power to a driven power transmission portion,
The power transmission member has a pair of walls facing each other with the power transmission part in between,
One of the pair of walls is provided with a protrusion that protrudes toward the power transmitting section,
An elastic member is provided on the other wall of the pair of walls,
A first abutting portion where the protrusion and the power transmitting portion abut, and a second abutting portion where the elastic member and the power transmitting portion abut both extend parallel to the axial direction. A power transmission device characterized in that it is not located on a virtual line.

Images