JP2002130586A - Adjustable leg device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an improved adjustable leg device to allow both positioning reliability and easy operability in higher level. SOLUTION: The adjustable leg device to adjust the height and the angle of a projector or the like comprises a grounding terminal 3, a leg component having a shank 5 extending from the grounding terminal, a casing 2 having a vertical hole 4 through the shank, a lock component 10 fit in the casing to allow movement in contact with and apart from the shank, an energization means 9 to energize the lock component in the direction welded to the shank with pressure, an operation component to displace the lock component from the shank, and a stopper means 19a to stop the lock component from displacing. This retains the shank position with the pressure welding force applied to the lock component in normal condition and freely adjusts the shank position by operating the operation component and separating the lock component from the shank.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an adjusting leg device for adjusting, for example, the optical axis angle of a projector and the level of a desk top.

[0002]

2. Description of the Related Art In order to adjust the optical axis angle of a projector and the horizontality of a desk top, it is common practice to incorporate screw means for converting rotational displacement into length displacement into legs. The lifting stroke of the height adjusting leg is determined by the relative rotation angle between the female screw and the male screw.

However, in the case of a screw standard represented by, for example, the ISO standard, the lead angle is such that a friction angle can be obtained with emphasis on stationary support of a large load. The stroke per rotation is small, which is preferable for fine adjustment, but unsatisfactory for quick adjustment.

As a solution to such a disadvantage, a shaft provided with a leg at the tip is inserted into a through hole, and the shaft is fixed by pressing the shaft with a push button member biased by a spring. Japanese Patent No. 2806 discloses a mechanism for releasing the pressing force acting on the shaft by pressing the push button member so that the position can be freely adjusted.
No. 358 discloses this.

[0005]

However, according to the above-mentioned mechanism, although quick adjustment is possible, since the fixing force of the shaft position relies exclusively on the press-contact force of the spring, the axial force overcoming the friction force is small. When acting on the shaft, there is a problem that the locked state of the leg cannot be maintained.

The present invention has been devised in order to solve such problems of the prior art, and the main object of the present invention is to increase the reliability of position holding and the easiness of operation to a higher level. It is an object of the present invention to provide an improved adjustment leg device that is compatible with the adjustment leg device.

[0007]

In order to achieve the above object, according to the first aspect of the present invention, the structure of an adjusting leg device for adjusting the height or angle of a projector or the like is changed to a grounding end (embodiment). A casing (including a grounding leg 3 in the embodiment) and a leg member having a shaft (a screw shaft 5 in the embodiment) extending from the grounding end, and a vertical through hole (4) through which the shaft is inserted. 2) and a lock member (10) slid on the casing so as to be movable toward and away from the shaft portion.
An urging means (compression coil spring 9 in the embodiment) for urging the lock member in a direction of pressing against the shaft portion, and a force for displacing the lock member in a direction for separating the lock member from the shaft portion. An operating member (operating lever 6 in the embodiment) for applying to the lock member, and a force transmitting means (cam mechanism 18 in the embodiment) for transmitting the force applied to the operating member to the lock member. And stopper means (protrusions 19a and 19b in the embodiment) for selectively preventing the displacement of the lock member according to the position of the operation member.

According to this, the position of the shaft is normally held by the pressing force applied to the lock member, and the lock member cannot be separated from the shaft unless the operating member is operated. By operating the operation member to separate the lock member from the shaft, the position of the shaft can be freely adjusted.

According to a second aspect, the force transmitting means includes:
The cam mechanism converts the rotational movement of the operating member into a linear movement of the lock member. Thereby, the operation of separating the lock member from the shaft can be simplified. In this case, especially claim 3
In other words, if the rotation axis of the operating member is orthogonal to the axis of the shaft, the direction of the operating force can be made to match the direction of the load applied to the leg member.

According to a fourth aspect of the present invention, the shaft portion and the lock member are provided with screw grooves which mesh with each other. As a result, the holding force at the time of normal operation is further enhanced, and fine adjustment by the screw becomes possible.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the accompanying drawings.

FIG. 1 shows the whole of an adjusting leg device constructed according to the present invention. The adjusting leg device 1 is fixed to the bottom of a housing of a device such as a projector. The casing 2 is fixed to the housing, and a grounding leg 3 is attached to a lower end thereof. A screw shaft 5 is inserted through the vertical through hole 4 and an operation lever 6 for releasing a locked state of the screw shaft 5 (to be described in detail later).

As shown in FIG. 2 and FIG. 3, the casing 2 has a rectangular cylindrical shape with its central axis extending in the horizontal direction, and the screw shaft 5 is inserted slidably in the vertical direction. A vertical through hole 4 is provided at one end thereof. A horizontal guide hole 7 is formed in the casing 2, and a slide block 8 is slidably held therein. The slide block 8 is resiliently urged by a compression coil spring 9 which is in close contact with the end wall of the guide hole 7.

A lock member 10 having a semicircular portion formed with a female screw 10a corresponding to the male screw 5a of the screw shaft 5 also slides into the guide hole 7. When the lock member 10 abuts and the female screw 10 a of the lock member 10 meshes with the male screw 5 a of the screw shaft 5, the axial displacement of the screw shaft 5 is regulated. The screw shaft 5 is prevented from coming off the casing 2 by an E-ring 11 fitted to the upper end thereof.

A horizontal shaft 12 extends from the back surface of the lock member 10, and the slide block 8 is integrally connected to its free end. That is, the lock member 10
Is movable in the horizontal direction in the casing 2 together with the slide block 8, and is constantly elastically urged by the compression coil spring 9 in a direction in which the female screw 10 a meshes with the male screw 5 a of the screw shaft 5.

A center boss 13 integrally formed with the operation lever 6 is fitted to an intermediate portion of the horizontal shaft 12 of the lock member 10. The center boss 13 is engaged with a slot 14 provided on a side surface of the casing 2 with a projection 15 so as to be immovable in the axial direction and rotatable within a predetermined angle range. By the operation of 6, it is possible to rotate around the horizontal shaft 12.

As shown in FIGS. 4 and 5, a cam mechanism 18 comprising a plurality of trapezoidal ridges 16 and 17 equally spaced in the circumferential direction is provided at an axially opposed portion between the slide block 8 and the center boss 13. Is provided. The peaks 16 and 17 of the slide block 8 and the center boss 13 are fitted to each other with a predetermined circumferential gap G therebetween.

As shown in FIG. 6, a pair of rib-shaped projections 19a and 1 are provided on the outer peripheral surface of the base end of the horizontal shaft 12.
9b are provided at an angle of about 90 degrees. These projections 19a and 19b are
When a is engaged with the male screw 5a of the screw shaft 5, the axial dimension is substantially equal to the gap opened between the opposing surfaces of the lock member 10 and the center boss 13.

On the side of the center boss 13 facing the lock member 10, the cross-sectional shape is fan-shaped,
An axial hole 20a large enough to receive the entire 19b;
20b are provided.

Next, the operation of the apparatus of the present invention will be described.

Normally, since the lock member 10 is pressed against the screw shaft 5 by the resilient force of the compression coil spring 9 applied to the slide block 8, the female screw 10a of the lock member 10 meshes with the male screw 5a of the screw shaft 5. In state. Therefore, by rotating the screw shaft 5, an axial displacement amount corresponding to the rotation angle determined by the lead angle of the screw is given to the screw shaft 5.

In this state, as shown in FIG. 6, a part of the axial end faces of a pair of rib-shaped projections 19a and 19b extending along the horizontal axis 12 from the back surface of the lock member 10 is centered. Since it interferes with the end face of the boss 13, this acts as a stopper means, and even if the elasticity of the compression coil spring 9 is lost, the male screw 5a of the screw shaft 5 and the locking member 1
The meshing state with the 0 internal thread 10a is maintained.

When the operating lever 6 is pushed up to rotate the center boss 13, the center boss 13 first rotates freely by the gap G between the cam ridges 16 and 17. By this first rotation, the axial end surfaces of the pair of projections 19a and 19b are aligned with the openings of the axial holes 20a and 20b, which form a sector of the center boss 13 (see FIG. 7A).

When the center boss 13 is further rotated from this state, the cam block 16 on the slide block 8 rides on the slope of the cam block 17 on the side of the center boss 13 that cannot move in the axial direction. Is the compression coil spring 9
To the left while compressing (see FIG. 5). As the slide block 8 is displaced leftward, the lock member 10 integrally connected to the slide block 8 is displaced leftward.
The rotation of the second stage is performed by a pair of rib-shaped protrusions 19a and 19b.
Is received in the fan-shaped axial holes 20a and 20b (see FIG. 7B).

As described above, since the female screw 10a of the lock member 10 is separated from the male screw 5a of the screw shaft 5, the screw shaft 5 becomes free. Therefore, the position of the screw shaft 5 in the axial direction is appropriately set, and the operating lever 6 is returned again.
0 is the internal thread 10 due to the pressing force of the compression coil spring 9.
a is pressed against the male screw 5 a of the screw shaft 5.
Cannot move in the axial direction, and its position is maintained. In this state, when the screw shaft 5 is rotated, the screw shaft 5 is displaced in the axial direction according to the lead angle of the screw, so that fine adjustment similar to that of a normal adjustment leg can be performed.

If the rotation shaft of the operation lever 6 is perpendicular to the axis of the screw shaft 5 as described above, the direction of the operation force for unlocking the screw shaft 5 is the direction of the load applied to the ground leg 3. Therefore, there is no need to apply a useless force to adjust the height.

Further, by employing the cam mechanism 18 as described above, it is possible to change the inclination of the cam ridges 16 and 17 without changing the pressing force of the lock member 10 against the screw shaft 5 without changing the pressing force of the operation lever 6. The operation stroke can be set appropriately.

Since the tops of the cam ridges 16 and 17 are cut off to form flat bearing surfaces 16a and 17a perpendicular to the axial direction, the cams 16 and 17 are rotated when the operation lever 6 is fully rotated. If the rotation angle is set so that the flat surfaces 16a and 17a at the top of the hill come into contact with each other, the slide block 8 is not pushed back even if the hand is released from the operation lever 6, and the free state of the screw shaft 5 can be maintained. Things. In this case, if the operation lever 6 is slightly returned to release the abutment between the flat surfaces 16a and 17a at the top of the cam ridge, the ridge and valley of the two naturally fit together and the slide block 8 is pushed out.

[0029]

As described above, according to the present invention, the locked state and the unlocked state of the leg in the axial direction can be selected by a simple operation, so that the coarse adjustment and the fine adjustment can be easily switched. be able to. In addition, since the locked state is not released in the normal state, a great effect can be achieved in improving the usability and holding reliability of the adjusting leg device.

[Brief description of the drawings]

FIG. 1 is an overall perspective view of the apparatus of the present invention.

FIG. 2 is a side sectional view taken along the line II-II in FIG.

FIG. 3 is a front view of the device of the present invention shown partially cut along the line III-III in FIG. 3;

FIG. 4 is an operation explanatory view of a cam mechanism showing a locked state.

FIG. 5 is an operation explanatory view of a cam mechanism showing an unlocked state.

FIG. 6 is an explanatory view of the operation of the stopper means in the locked state.

FIG. 7 is a view for explaining the operation of the stopper means when the lock is released.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 adjustment leg device 2 casing 3 grounding leg 4 vertical through hole 5 screw shaft 6 operating lever 7 guide hole 8 slide block 9 compression coil spring 10 lock member 12 horizontal shaft 13 center boss 16 cam ridge (slide block side) 17 cam ridge ( (Center boss side) 18 Cam mechanism 19a / 19b Projection 20a / 20b Axial hole

Claims (4)

[Claims] 1. An adjusting leg device for adjusting a height or an angle of a projector or the like, comprising: a leg member having a grounding end and a shaft extending from the grounding end; and a vertical penetration penetrating the shaft. A casing provided with a hole, a lock member slidably fitted to the casing so as to be able to move toward and away from the shaft portion, a biasing means for biasing the lock member in a direction of pressing against the shaft portion, An operation member for applying a force for displacing the lock member in a direction to separate the lock member from the shaft portion to the lock member; a force transmission unit for transmitting a force applied to the operation member to the lock member; and the lock member. Stopper means for selectively preventing said displacement according to the position of said operating member. 2. The adjusting leg device according to claim 1, wherein the force transmitting means is a cam mechanism that converts a rotational motion of the operation member into a linear motion of the lock member. 3. The adjustment leg device according to claim 2, wherein a rotation axis of the operation member is orthogonal to an axis of the shaft portion. 4. The adjusting leg device according to claim 1, wherein the shaft portion and the lock member have screw grooves that mesh with each other.