JPH0815774A - Overhead projector - Google Patents

Abstract

PURPOSE:To quickly lock an arm for erecting a projecting head when it is not used and to quickly release the lock thereof when it is used by simple work. CONSTITUTION:When an overhead projector is carried, a grip 40 is moved in a horizontal direction with respect to an OHP main body 10. Then, a stopper pin 66 is depressed by a flange 62 and fitted to an engagement hole 70 by the rotation of a cam barrel 64. Thus, since the rotation of a rotary shaft 22 is locked by the pin 66, the projection head 18 is prevented from jumping out of the main body 10. When the overhead projector is used, the grip 40 is moved in a direction orthogonally crossed to the main body 10. Then, the pin 66 is slid and moved along the flange 62 by the rotation of the cam barrel 64 and the energizing force of a spring 78 and retreated from the hole TO. Thus, since the lock by the pin 66 is released, the head 18 is erected through the arm 20.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an overhead projector, and more particularly to an overhead projector in which an arm to which a projection head having a projection lens is attached is rotatably supported by an overhead projector body.

[0002]

2. Description of the Related Art In a conventional overhead projector, a transparent original is placed on a reflective Fresnel lens fixed to the upper surface of an overhead projector body (hereinafter abbreviated as "OHP body"), and
The reflective Fresnel lens is illuminated by a light source provided in the projection head, the transparent original is illuminated by the reflected light of the reflective Fresnel lens, and the transmitted image light of the transparent original is projected by the projection lens provided in the projection head. There is a so-called reflective overhead projector that enlarges and projects on a screen by a mirror.

The projection head is attached to the tip of an arm, and the base of the arm is rotatably supported on the side surface of the OHP body. Most of such overhead projectors are portable type, and when used, the arm is rotated in the upright direction to position the projection head above the reflective Fresnel lens, and when not in use, the arm is rotated in the fall direction to project the projection head. Is stored in the OHP body and can be stored or carried as it is.

Further, this type of overhead projector is provided with a dedicated lock member for locking the rotating shaft of the arm, and by locking the arm by this lock member, the OHP of the projection head is not used when the projector is not in use, especially when carrying the projector. I try not to jump out of the body.

[0005]

However, in the conventional overhead projector, the lock member has to be attached to the rotary shaft of the arm every time it is carried, and the lock member must be removed from the rotary shaft of the arm each time it is used. Therefore, there is a drawback that a troublesome work is required to lock / unlock the arm.

The present invention has been made in view of such circumstances, and in a series of operating procedures from when not in use to preparation for use, the arm is locked when not in use and the lock is released when it is used. It is an object of the present invention to provide an overhead projector that can be quickly performed by a simple operation.

[0007]

In order to achieve the above-mentioned object, the present invention has a base portion of an arm rotatably supported by an overhead projector body, and a projection lens is attached to the tip portion of the arm. A projection head having
When the overhead projector is used, the arm is pivoted in the upright direction with the base end portion as a fulcrum, and when the overhead projector is not used, the arm is folded with the base end portion as a fulcrum. In a portable overhead projector, the handle is rotatably supported by an overhead projector body, locks the rotation of the arm in conjunction with a rotating operation of the handle in a first direction, and the handle is It is characterized in that the lock is released in conjunction with the turning operation in the second direction.

[0008]

According to the present invention, the handle which is gripped when carrying the overhead projector is rotatably attached, paying attention to the turning position of the handle when carrying the overhead projector, and by locking / unlocking the arm according to the position of the handle. The arm can be locked / unlocked easily and quickly.

That is, according to the present invention, when the handle is rotated in the first direction when the direction in which the handle is rotated in the convenient direction when carrying the overhead projector is the first direction, The rotation of the arm is locked in synchronization with the rotation operation. Further, when the overhead projector is used, if the handle is rotated in the second direction, the lock is released in conjunction with the rotation operation.

An overhead projector according to a second aspect of the present invention is provided with a restricting means for restricting rotation of a handle, and the handle is rotated at a rotation position in the first direction and a rotation position in the second direction of the handle. I regulated the movement. Thus, in the present invention, since the regulation means can prevent the handle from rotating unintentionally, the reliability of the lock / unlock of the arm can be improved.

An overhead projector according to a third aspect of the invention is configured by a click mechanism of the regulating means.
Thereby, in the present invention, the position of the handle is the first,
Alternatively, it is possible to recognize whether or not it is surely located at the rotation position in the second direction.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of an overhead projector according to the present invention will be described in detail below with reference to the accompanying drawings. FIG. 1 is a side view showing an appearance of an overhead projector according to the present invention in a use state, and FIG. 2 is a side view showing an appearance of a non-use state. Overhead projector O
The HP main body 10 is formed in a box shape having an upper surface opened, and a reflective Fresnel lens 12 is fixed to the upper surface opening. On this reflective Fresnel lens 12, a transparent original (not shown) is placed while maintaining its flatness. OHP
A cover 16 is rotatably provided on the right edge of the main body 10 in FIG. 1 via a hinge 14. This cover 16 is released from the OHP main body 10 as shown in FIG. 1 when the overhead projector is used, and as shown by a chain double-dashed line in FIG. 2 when the overhead projector is not used.
It is closed on the body 10. As a result, the reflective Fresnel lens 12 and the projection head 18 described later are protected by the OHP body 10 and the cover 16. The reflective Fresnel lens 12 is swingably attached to the left end portion 12A in FIG. 2 as a fulcrum, and when not in use, is inclined downward to the right as shown in FIG. It has been blocked.

An arm 20 is provided at the left end of the OHP main body 10 in FIG. As shown in FIG. 3, this arm 20 is rotatably attached around a rotary shaft 22 connected by a pin 21, and within a range from the use position shown in FIG. 1 to the non-use position shown in FIG. It is rotatable. The projection head 18 has a pin 24 at the upper end of the arm 20.
It is rotatably attached with the fulcrum as a fulcrum. The projection head 18 is positioned at a predetermined projection position directly facing the reflective Fresnel lens 12 in a state where the arm 20 is erected in the use position shown in FIG. Further, the projection head 18 is positioned at the position folded by the arm 20 in a state where the arm 20 is laid down in the unused position shown in FIG.

As shown by the dotted line in FIG. 1, the projection head 18 has a light source lamp 26 for irradiating the reflective Fresnel lens 12 and light condensed by the reflective Fresnel lens 12, that is, transmitted image light transmitted through a transparent original. Projection lens 2 for projecting
8 are provided. A projection mirror 30 is provided above the projection lens 28 so as to be tiltable about a pin 31 as a fulcrum. When the projection mirror 30 is used, the projection lens 28
The image light transmitted through the projection lens 28 can be reflected toward a screen (not shown) by being tilted at 45 ° with respect to the optical axis of.

On the other hand, a handle 40 used when carrying the OHP body 10 is attached to the left end portion of the OHP body 10 in FIG. As shown in FIG. 3, the handle 40 is rotatable within a range of 180 ° from A to B in FIG. 1 by rotating shafts 42 and 44 connected to both ends thereof. The rotary shaft 42 is, as shown in FIG.
Is rotatably supported by bearings 46 and 48 formed in 0,
The rotating shaft 44 is rotatably supported by bearings 50 and 52. An arm lock / unlock mechanism 60 interlocked with the above-described rotation of the handle 40 is provided in the OHP main body 10, and the arm lock / unlock mechanism 60 allows the arm 2 to move.
It is designed to lock / unlock 0.

The arm lock / unlock mechanism 60 has a cam cylinder 64 (see FIG. 4) having a spiral collar 62 formed on the peripheral surface thereof, a stopper pin 66, and an engagement formed on a flange portion 68 of the rotary shaft 22. It is composed of holes 70. The cam barrel 64 is connected to the rotary shaft 44 by a pin 72 and can rotate along with the rotary shaft 44, that is, in association with the rotation of the handle 40. The base end portion 66A of the stopper pin 66 is in contact with the flange 62 of the cam barrel 64. The stopper pin 66 is a bearing 74 formed on the OHP main body 10,
3 is supported by 76 so as to be slidable in the vertical direction in FIG. 3, and is urged downward in FIG. 3 by the urging force of a spring 78 fitted on the outer peripheral surface thereof. Therefore, the stopper pin 66 is pressed and brought into contact with the flange 62 of the cam barrel 64 at the base end portion 66A thereof by the urging force of the spring 78. As a result, the stopper pin 66 slides upward in the drawing when the handle 40 is rotated in the horizontal direction (first direction, that is, a convenient position for carrying) with respect to the OHP body 10 by the action of the collar 62. Moved again, handle 4
When 0 rotates in the direction orthogonal to the OHP body 10 (the second direction) (position A and position B in FIG. 2), it is slid downward as shown in FIG.

The engagement hole 70 formed in the flange portion 68 of the rotary shaft 22 is provided with the stopper pin 66 when the projection head 18 is housed in the OHP body 10 (see FIG. 2).
When the handle 40 is moved to the horizontal position in this state, it is fitted into the tip portion 66B of the stopper pin 66. As a result, the rotation of the rotary shaft 22 is locked by the stopper pin 66, so that the projection head 18 can be prevented from jumping out of the OHP main body 10. Further, when the handle 40 is moved in the orthogonal direction, the stopper pin 66 retracts from the engagement hole 70, so that the lock of the rotary shaft 22 can be released.

On the other hand, the rotating shaft 42 of the handle 40 is provided with a click mechanism 80 as shown in FIGS. The click mechanism 80 includes a ball 82, grooves 84, 86 and 88 (see FIG. 6) with which the ball 82 engages, and a spring that urges the ball 82 into one of the grooves 84, 86 and 88. It consists of 90. The ball 82 and the spring 90 are arranged in a through hole 92 formed in the bearing 46, and a retaining ring 94 screwed to the through hole 92 prevents the ball 82 and the spring 90 from falling out of the through hole 92. The grooves 84, 86, 88 are formed in the flange portion 96 formed at the end of the rotary shaft 42, and the flange portion 96 is formed.
As shown in FIG. 6, they are formed at 90 ° intervals. Therefore, the ball 82 engages with the groove 84 when the handle 40 is in the horizontal position with respect to the OHP main body 10, and when the handle 40 is in the direction orthogonal to the OHP main body 10, the groove 8 is provided.
6 or engage the groove 88. As a result, the handle 40 is
The click mechanism 80 holds the horizontal position and the orthogonal position.

Next, the operation of the arm lock / unlock mechanism 60 and the click mechanism 80 of the overhead projector constructed as described above will be described. First, FIG. 2 and FIG.
As shown in FIG. 3, after the projection head 18 is housed in the OHP main body 10, when carrying the overhead projector, the handle 40 is moved to the horizontal position with respect to the OHP main body 10. When the handle 40 is moved to the above position, the stopper pin 66 is pushed by the flange 62 by the rotation of the cam barrel 64 and slides, and is fitted into the engaging hole 70 formed in the flange portion 68 of the rotary shaft 22. Therefore, in this embodiment,
Since the rotation of the rotary shaft 22 is locked by the stopper pin 66, the projection head 18 is held by the OHP main body 10 when being carried.
You can prevent it from jumping out.

At this time, since the ball 82 of the click mechanism 80 is fitted in the groove 84 shown in FIG. 6, the position of the handle 40 carrying the overhead projector is surely stable. As a result, in this embodiment, the projection head 18 does not pop out of the OHP body 10 when being carried by mistakenly rotating the handle 40. Next, in FIG.
As shown in FIG. 5, when using the overhead projector, the handle 40 is moved in a direction orthogonal to the OHP body 10. When the handle 40 is moved in the above direction, the stopper pin 66 rotates the cam barrel 64 and the spring 78.
It is slid along the brim 62 by the urging force of and is retracted from the engagement hole 70. Therefore, in this embodiment,
Since the lock by the stopper pin 66 is released, the projection head 18 can be erected via the arm 20.

Further, at this time, since the ball 82 of the click mechanism 80 is fitted in the groove 86 or the groove 88 shown in FIG. 6, the projection head 18 is used by mistakenly rotating the grip 40 when the projection head 18 is used. There is no problem of being unable to stand up from. As described above, in the present embodiment, the arm 40 is operated during a series of operating procedures from when not in use to preparation for use by the handle 40 and the arm lock / unlock mechanism 60 which is interlocked with the rotating motion of the handle 40. Since the lock / unlock is performed, the dedicated lock member used conventionally is not required. As a result, in this embodiment, the lock / unlock of the arm can be quickly performed by a simple operation.

Further, in this embodiment, since the click mechanism 80 is used as the regulating means for the handle 40, it is possible to recognize whether or not the position of the handle 40 is surely located in the horizontal direction or the orthogonal direction. In this embodiment, the example applied to the reflection type overhead projector has been described, but the present invention is not limited to this, and a so-called transmission type overhead in which a light source lamp is installed in the OHP main body to illuminate a transparent original from below. It may be applied to a projector.

[0023]

As described above, according to the overhead projector of the present invention, the handle of the overhead projector is rotatably attached, and the arm is locked / unlocked according to the turning position of the handle. Therefore, the arm can be locked / unlocked quickly with a simple operation.

[Brief description of drawings]

FIG. 1 is a side view showing a usage state of an overhead projector according to the present invention.

FIG. 2 is a side view of the overhead projector according to the present invention including a partial breakage of the overhead projector when not in use.

FIG. 3 is a plan view of the overhead projector according to the present invention including a partial cutaway of the unused state.

FIG. 4 is a perspective view showing an embodiment of a cam barrel applied to an arm lock / unlock mechanism of an overhead projector according to the present invention.

FIG. 5 is a plan view of the overhead projector according to the present invention in which the overhead projector is in use and partially broken.

FIG. 6 is an explanatory diagram of a click mechanism applied to an overhead projector according to the present invention.

[Explanation of symbols]

 10 ... OHP main body 18 ... Projection head 20 ... Arm 40 ... Handle 60 ... Arm lock / release mechanism 62 ... Tsuba 64 ... Cam barrel 66 ... Stopper pin 70 ... Engagement hole 80 ... Click mechanism 82 ... Ball 84, 86, 88 ... Groove 90 ... Spring

Claims (3)

[Claims] 1. A base end portion of an arm is rotatably supported by an overhead projector main body, and a projection head having a projection lens is attached to a tip end portion of the arm. In the overhead projector that is rotated in the standing direction with the base end as a fulcrum, the arm is folded around the base end as a fulcrum when the overhead projector is not used, and is carried while grasping the handle when carrying the overhead projector. The handle is rotatably supported by the main body of the overhead projector, locks the rotation of the arm in conjunction with the rotation of the handle in the first direction, and rotates the handle in the second direction. An overhead projector characterized in that the lock is released in conjunction with. 2. A restricting means for restricting the rotation of the grip at the rotation position in the first direction and the rotation position in the second direction is provided. The described overhead projector. 3. The overhead projector according to claim 2, wherein the restricting means is a click mechanism.