JPH0445360B2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a guide device for a balance weight in a rail type flexible parallel ruler, a coordinate analyzer, a parallel ruler, etc., and in particular, the present invention relates to a guide device for a balance weight in a rail type flexible parallel ruler, a coordinate analyzer, a parallel ruler, etc. It is characterized by this.

The applicant has already developed a device that uses the repulsive force of a magnet to levitate a balance weight into the weight insertion space of a vertical rail, thereby reducing the running friction of the balance weight along the vertical rail. has been done. When the repulsive force of a magnet is used to reduce the running friction of a balance weight, the following defects occur. That is, in this type of device, the vertical rail is supported by a drawing board that can be tilted between a state that is substantially horizontal to the floor surface and a state that is tilted at approximately 80° in the upright direction. Therefore, when the drawing board is horizontal to the floor, the load applied perpendicularly to the bottom wall surface of the balance weight that forms the weight insertion space is the largest, and the drawing board is at approximately 80 degrees to the floor. When the balance weight is in an upright state, the load of the balance weight applied perpendicularly to the bottom surface of the weight insertion space is the smallest. This means that when the weight of the balance weight is supported by the repulsive force between a magnet disposed on the bottom of the weight insertion space and a magnet disposed opposite to it on the balance weight, the opposing gap between the magnets will change significantly. If the opposing gap between the magnets changes greatly in this way, the balance weight will move up and down significantly within the weight insertion space, and therefore the vertical width of the weight insertion space must be set wide. The vertical rail becomes too large.

In addition, when it is desired to set the level of the balance weight to a predetermined state with respect to the bottom of the weight insertion space, high precision is required in selecting the magnetic force of the magnet, and for quality control reasons, the optimum magnet must be selected and adopted. There was a lot of annoyance.

The present invention aims to eliminate the above-mentioned defects. The present invention will be described in detail below with reference to embodiments of a rail-type universal parallel ruler shown in the accompanying drawings.

In FIG. 1, reference numeral 2 denotes a drawing board, which is fixed to a drawing board support frame of a drafting table (not shown). The drawing board support frame is configured so that it can be set to any inclination angle between a horizontal state with respect to the floor surface and a state where it stands upright at approximately 80 degrees with respect to the floor surface. 4
is a horizontal rail fixed to the upper edge of the drawing board 2 by a vise-type fixture, and a horizontal cursor is movably attached to this rail. The upper end of the vertical rail 6 is rotatably supported at the rising portion of the horizontal cursor via a bracket so as to be rotatable about an axis parallel to the longitudinal direction of the horizontal rail 4. A tail roller is rotatably supported at the lower end of the vertical rail 6, and the tail roller is mounted on the upper surface of a guide rail 8 disposed at the lower edge of the drawing board 2 so as to be freely movable.

As shown in FIG. 2, a vertical cursor 16 is movably attached to the vertical rail 6 via vertical rollers 10 and 12 and a horizontal roller 14, and a hinge member 18 is attached to the rising portion of the vertical cursor 16. A head 20 is connected. Straight rulers 22 and 24 are removably fixed to the ruler mounting plate of the head 20. Reference numeral 26 denotes a weight insertion space formed in the vertical rail 6 over the entire length thereof, and grooves are formed in both side walls forming the space 26 over the entire length in the longitudinal direction. Magnets 28 and 30 each made of band-shaped magnetic rubber are fitted and fixed together with the iron plate. The magnet 2
The surfaces of 8 and 30 are set perpendicular to the two surfaces of the drawing board, and two different magnetic pole faces are formed along the longitudinal direction on the surfaces. A pair of vertical rail surfaces 32 and 34 are formed at the bottom of the weight insertion space 26 along the longitudinal direction. 36
is a balance weight placed in the weight insertion space 26, and its weight is set to be the same as the total weight of the vertical cursor 16, hinge member 18, head 20, and straightedges 22, 224. Magnets 38 and 4 are provided on both sides of the balance weight 36 so that their polarities are opposite to the magnets 28 and 30.
0 is placed. The balance weight 36
Three lateral rollers are rotatably supported in the recessed portion of the lower surface of the , the lateral rollers 42 at both ends rotatably abut on the vertical rail surface 32, and the lateral rollers 44 at the middle portion are rotatably supported on the vertical rail surface 32. It is rotatably in contact with the The horizontal position of the balance weight 36 in the space 26 is regulated by the horizontal rollers 42 and 44, whereby the magnet 28
and 38, and 40 and 30 face each other with the same gap.

The vertical cursor 16 and the balance weight 36 are interlocked in opposite directions along the vertical rail 6 by a wire rope stretched between rope pulleys rotatably supported at both ends of the vertical rail 6. It is connected.

The magnitude of the attractive magnetic force acting between the magnets 28 and 38 is set to be the same as the magnitude of the attractive magnetic force acting between the magnets 30 and 40.
Due to the attractive magnetic force between 8 and 30 and 40, the bottom surface of the balance weight 36 is inserted into the weight insertion space 26.
It is floating at a predetermined distance from the bottom surface. Thin frictional force reducing members are bonded to the bottom surface of the balance weight 36 and the bottom surface of the weight insertion space 26 facing thereto, respectively. In addition, the horizontal direction regulation of the balance weight 36 is as shown in FIG.
A vertical rail surface 50 is provided above the weight insertion space.
Horizontal rollers 56 and 58 rotatably supported in the upper recessed part of the balance weight 54 are brought into contact with the vertical rail surface 50, and the vertical rail surface 5
2, a horizontal roller 60 may be brought into contact with it. Further, as shown in FIG. 5, magnets 66 and 68 are arranged on the vertical rail surface of the weight insertion space 62,
Magnets 72 and 74 may be disposed on both sides of the lower part of the balance weight 70, with the same polar surfaces facing the magnets 66 and 68.

Next, the operation of this embodiment will be explained.

When the handle of the head 20 is pressed by hand in any direction horizontal to the two surfaces of the drawing board, the vertical rail 6
In FIG. 1, the head 20 is moved to an arbitrary position on the drawing board 2 by moving along the horizontal rail 4 in the left-right direction and moving the vertical cursor 16 along the vertical rail 6. I can do it. Vertical cursor 1
6 moves along the vertical rail 6, the balance weight 36 moves along the vertical rail 6 in conjunction with the vertical cursor 16 and floats within the weight insertion space 26 of the vertical rail 6, and with respect to the vertical cursor 16. Move in the opposite direction. Even if you take your hand off the head 20 when the drawing board 2 is tilted, the head 20
is balanced with the balance weight 36, and the head 20 will not fall along the two surfaces of the drawing board.
When the inclination angle of the drawing board 2 is changed from, for example, horizontal to the floor surface to an inclination angle of approximately 80°, the weight of the balance weight 36 causes the bottom surface of the weight insertion space 26 to be perpendicular to the drawing surface. The load in the direction changes to the direction of reduction. However, due to this load change, the magnets 38, 40
Although the magnets 38 and 40 are slightly displaced in the upward direction relative to each other, the amount of rise is very small, and the upper ends of the magnets 38 and 40 do not move above the upper ends of the magnets 28 and 30. That is, no matter how large the above-mentioned load change is, the upper end level of the magnets 38 and 40 remains the same as that of the magnets 28 and 40.
It becomes stable at a position slightly lower than the upper end of 30. This means that even if a magnet with a much stronger magnetic force than the optimum magnetic force for supporting the weight of the balance weight 36 is used, the balance weight 36 will not rise too high within the weight insertion space 26.
That is, any magnet may have a magnetic force equal to or greater than a predetermined magnetic force, and a considerable range of magnet selection is allowed. In this embodiment, a rail type universal parallel ruler has been described, but the above device can also be applied to a rail type coordinate analyzer and a rail type parallel ruler.

As described above, in the present invention, the balance weight is floated in the weight insertion space of the vertical rail by the attractive force of the magnet, so even if the load of the balance weight on the bottom of the weight insertion space changes, the balance weight is The vertical movement change in the weight insertion space can be reduced, the weight insertion space, that is, the vertical rail, can be made smaller, and since precision is not required for the magnitude of the magnet's magnetic force, quality control of the magnet can be improved. This has the advantage that it is easy to do so.

[Brief explanation of the drawing]

The drawings show a preferred embodiment of the present invention, in which Fig. 1 is an overall plan view of a rail type universal parallel ruler, Fig. 2 is a cross-sectional view, Fig. 3 is a cross-sectional view showing another embodiment, and Fig. 4 is a cross-sectional view showing another embodiment.
This figure is a plan view of the same, and FIG. 5 is a sectional view showing another embodiment. 2...Drawing board, 4...Horizontal rail, 6...Vertical rail, 8...Guide rail, 16...Vertical cursor,
18... Hinge member, 20... Head, 22,2
4... Straight ruler, 26... Weight insertion space, 3
2, 34... Vertical rail surface, 28, 30... Magnet, 36... Balance weight, 38, 40...
magnet.

Claims (1)

[Claims] 1. A long vertical rail supported by a drawing board, a vertical cursor attached movably along the vertical rail, and a balance weight insertion space formed over the entire length of the vertical rail. In a balance weight guide device for a rail-type flexible parallel ruler, etc., the balance weight is movably arranged along the longitudinal direction of the cursor and in a direction opposite to the vertical cursor, the balance weight insertion space is formed. Magnets are arranged parallel to each other over the entire length of the drawing on both sides perpendicular to the surface of the drawing board, and the balance is arranged such that different poles face the magnets with an appropriate interval. Magnets are arranged on both sides of the weight, and a downward load in a direction perpendicular to the drawing surface of the balance weight is supported by the attractive magnetic force that acts between the magnets with opposite polarities. A balance weight guide device for a rail type flexible parallel ruler, etc., characterized in that: