JPS595376Y2 - Tilt balance device on drafting table - Google Patents

Description

[Detailed description of the invention] Industrial application field This invention is based on the invention that the center of gravity of the total weight of the drawing board, drawing machine, drafting light, etc. placed on the drawing board support frame of the drawing table is To provide a tilt balance device in a drafting table which prevents a danger caused by a falling moment reversed in the opposite direction of a drawing board support frame when the drawing board support frame moves to the opposite side of a perpendicular line passing through a rotation support shaft of the drawing board support frame as the inclination increases.

゛Background Art and Problems Generally speaking, a drafting table variably adjusts the inclination angle of the drawing board support frame to a desired angle in the range of approximately 0 to 75 degrees according to the drafting work, and supports the drawing board at this set angle. The frame can be fixed.

In conventional drafting tables, a reaction force is generated using a torsion coil spring or a torsion bar, and this reaction force is used to balance the falling moment of the drawing board support frame when variably adjusting the inclination of the drawing board. When the torsion coil spring or torsion bar actually acts, the reaction force acts at a high speed, and if the balance of the inclination of the drawing board support frame is lost, the inclination fixing device can be released and the drawing machine, drawing light, etc. Accidents have occurred where the attached drawing board suddenly rotates and injures the worker or someone near the drawing table.

Furthermore, accidents have occurred in which the drawing machine attached to the drawing board was damaged when the tilt balance was lost.

On the other hand, if the inclination of the drawing board support frame increases, the overall center of gravity of the drawing board support frame will be The position of is moved to the front of the drafting table beyond the perpendicular line passing through the pivot axis of the drawing board support frame, and the falling moment of this drawing board support frame is reversed and acts while the drawing board inclination is small. The direction of the reaction force moment coincides with the direction of the reaction force moment caused by the drafting, which inconveniently causes the drawing board support frame to tip over in front of the drawing table, creating a risk of damaging the drafting worker and equipment such as the drawing machine.

OBJECT OF THE INVENTION The object of the present invention is to eliminate the drawbacks of the prior art and provide a tilt balance device for a drafting table that can change the direction of the reaction moment even when the falling moment of the drawing board support frame is reversed.

Summary of the invention In order to achieve the above object, the present invention is designed to reduce the falling moment caused by the inclination of the drawing board support frame between the drawing board support frame which is pivotably supported so as to be tiltable and the column supporting the drawing board support frame. An air spring is arranged so that a reaction force moment is generated against the air spring, and the mounting position can be slid freely within a predetermined range, and a spring member is arranged at one end of the air spring on the column side so that the air spring can be bounced freely. It is characterized by supporting the following.

EXAMPLE Hereinafter, an example of the present invention will be explained based on FIGS. 2 to 4.

FIG. 1 shows an external side view of a drafting table 1 on which an inclination balance device 12 of the present invention is implemented.

This drafting table 1 includes a pedestal 2 placed on the floor of an office or the like, a fixed support 3 planted on the pedestal 2, an elevating support 4 built into the fixed support 3 so as to be movable up and down, and an elevating support 4. It consists of a tilting bracket 5 disposed on the upper end of the board so as to be tiltable, and a drawing board support frame 6 fixed to the tilting bracket 5.

A fluid pressure cylinder (not shown) is built in between the fixed column 3 and the lifting column 4, and performs lifting and lowering operations and fixing operations of the lifting column 4.

The tilting bracket)・5 is the first one with the pivot shaft 7 as the center.
In the figure, a drawing board 8 is placed on the drawing board support frame 6, which is rotated clockwise or counterclockwise, and a horizontal rail 9 of a drawing machine is mounted on the upper end of this drawing board 8. .

A vertical rail 10 that can run freely in the lateral direction of the drawing board 8 is arranged on the horizontal rail 9.

A head portion 11 is disposed on the vertical rail 10 so as to be freely movable via a vertical carriage (not shown).

When the inclination of the drawing board 8 is approximately in the range of 0 to 60', a clockwise falling moment in FIG. 1 is acting on the drawing board support frame 6.

FIG. 2 shows the entire structure of the tilt balance device 12 incorporated inside the fixed column 3 and the lifting column 4 in FIG. 1.

As can be seen from FIG. 2, a mounting bracket 13 is provided to protrude downward from the drawing board support frame 6.

The fixed position of the mounting bracket 13 corresponds to the rear side of the pivot shaft 7 (to the right of the pivot shaft 7 in FIG. 1).

This mounting bracket 23 is provided with a first mounting hole 14, a second mounting hole 15, a third mounting hole 16, and a fourth mounting hole 17. They are arranged so as to be located successively further away from the axis 7 and at the same time sequentially located downward.

On the other hand, an air spring 18 is arranged inside the lifting column 4, and one end 18a of this air spring 18 is disposed inside the lifting column 4.
are attached to the above mounting holes 14゜15.16 and 1 through screws 19.
The mounting is fixed in any one of the mounting holes 7.

On the other hand, as shown in FIG. 3, the other end 18b of the air spring 18 is formed into a yoke shape and is pivotally supported on a pivot shaft 29 disposed on a mounting bracket 28 fixed to the lifting column 4. ing.

On the other hand, long holes 34 are bored in the mounting brackets 28 on both sides in an upward and diagonal direction.

This length (L34) is guided by the pivot 29 and moved in the -E direction or downward, and at the same time is fixed while being braked.

Note that retaining rings 30 are attached to both ends of the pivot shaft 29 to prevent the shaft 29 from coming off the bracket 28.

The air spring 18 is preferably of a cylinder type in which compressible air is enclosed in an incompressible fluid (for example, hydraulic oil).

The reason for this is that when setting the inclination of the drawing board 8 by loosening the tilt fixing mechanism (not shown) to make the drawing board support frame 6 free from tilting, the drawing board 8 does not undergo unnecessary swinging. This is because the tilt setting operation can be performed stably.

Of course, a cylinder type device that only confines air can also be used.

Since the operating speed of this air spring 18 is low, even if the balance of the moment due to the reaction force of this air spring 18 is lost with respect to the moment of falling of the drawing board support frame 6 (in the clockwise direction in FIG. 2), Since the plate support frame 6 does not rotate rapidly, it will not injure people or attached equipment.

Further, a tension spring 35 is arranged between the pivot shaft 29 and the mounting bracket 28 to balance the falling moment of the drawing board support frame 6 in the counterclockwise direction in FIG.

As described above, according to the embodiment having the above configuration, when the drafting light 26 is attached to the upper end of the vertical rail 10 of the box making machine so as to protrude in front of the drawing board 8, as shown in FIG. It is suitable for

That is, the inclination of the drawing board support frame 6 becomes large and the drawing board support frame 6
The position of the integrated center of gravity A of the drawing board 8, the drawing machine, the drawing light 26, etc. placed on top is to the left in FIG. If it moves, a moment will be generated in the drawing board support frame 6 that causes it to fall in the counterclockwise direction in FIG. On the contrary, it will increase.

This inconvenience occurs when the other end 18b of the air spring 18 is attached to the mounting bracket 2 attached to the inner wall surface 4a of the lifting column 4.
Slide it upward against 8 and press 1 at that position.
This is solved by determining

Therefore, for example, when the drawing board support frame 6 is tilted in the range of more than 60 degrees to 75 degrees, the air spring 18 is fully extended and the other end 18b is the elongated hole 3.
4 from the lower end toward the upper end to prevent sudden rotation of the drawing board support frame 6 in the counterclockwise direction (in FIG. 4).

Effects of the invention As described above, according to the invention, even when the inclination of the drawing board support frame becomes large and the falling moment of the drawing board support frame is reversed, the direction of the reaction force moment of the air spring is reversed. It is possible to prevent the falling moment and the reaction force moment from being compounded in the same direction, thereby preventing damage to people and equipment.

[Brief explanation of drawings]

Fig. 1 is an external side view of a drafting table incorporating the inclination balance device of the present invention, Fig. 2 is an enlarged cross-sectional view of the main part showing an example of the above-mentioned inclination balance device, and Fig. 3 is the installation of the air spring to the lifting column. 4 is an enlarged front view showing the structure, and FIG. 4 is an external side view of the drafting table with a drafting light etc. attached to the drawing board. 1...Drawing table, 3...Fixed support, 4.
...Elevating support column, 6...Drawing board support frame, 7.
...Rotation shaft, 12...Inclination balance device, 28.30...Mounting bracket, 18
...Air spring, 18a...One end, 18b...Other end, 34...Elongated hole,
35... tension spring.

Claims (1)

[Scope of utility model registration request] A reaction moment is generated between the drawing board support frame which is pivotably supported so as to be tiltable and the column supporting this drawing board support frame against the falling moment due to the inclination of the drawing board support frame, and the mounting is carried out within a predetermined range. An inclined drafting table characterized in that an air spring is disposed so as to be slidable in position, and a spring member is disposed at one end of the air spring on the column side so as to be resiliently supported. balance device.