JPH0114468Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a floating support device for a head portion of a universal parallel ruler.

Conventionally, this type of device supports the load of the head and scale using spring elasticity, but the load W of the head and scale on the drawing surface is determined by the inclination angle θ of the drawing board with respect to the horizontal.
As expressed by W cos θ, there is a large change from W to 0, so it was necessary to change the spring elasticity for supporting the head when the inclination angle of the drawing board changed.

SUMMARY OF THE INVENTION The present invention provides a floating support device for the head of a universal parallel ruler, which can support the head and scale at a floating position relative to the drawing surface regardless of the inclination angle of the drawing board.

The device of the present invention will be explained in detail with reference to the embodiments shown below. 1 is a cursor side link fixed to a cursor plate that moves along a vertical rail, 2 is a head support link fixed to a head part, and both links 1 , 2 are connected by a conventionally known parallel movement mechanism, and the head support link 2 is configured to move up and down with respect to the cursor side link 1 substantially parallel to the drawing surface. In the embodiment, 3 is an upper link constituting a part of the parallel movement mechanism, and the cursor side link 1
P ₁ for head support link 2;
They are connected rotatably around _P2 as their respective axes.
In addition, the lower link, which is omitted in the figure, is connected in parallel to the upper link 3, for example, rotatably connected to the cursor side link 1 at P ₃ and the head support link 2 at P ₄ respectively. The upper and lower links constitute a parallel movement mechanism.
In addition, the lower link is constructed using, for example, a conventionally known swing lever or cam member so that the fulcrums P ₃ and P ₄ can be separated from each other, and the head support link 2 is arranged around the axis P ₂ . It is constructed so that it can be rotated arbitrarily in the counterclockwise direction. Considering the positional relationship of the head support link 2 with respect to the cursor side link 1 connected by this parallel movement mechanism, it is possible to move from the position where the scale contacts the drawing board surface in Figure 1 to the floating position of the head and scale in Figure 2. During movement, the distance between, for example, point P ₃ of cursor side link 1 and point P ₂ of head support link 2 or upper link 3 increases, so that a bendable part that is in tension at the floating position between these two points increases. If a tension member is provided, the head portion and scale can be supported in the floating position, and by being bent, the tension member can be brought into close contact with the drawing surface.

Since the above-mentioned point P2 is the position of the axis connecting the upper link 3 and the head support link 2, it is a point on the upper link 3 and at the same time the head support link 2.
This is also the point above. Therefore, one end of the tension members 4, 7 having a bent part in the middle is connected to point P3 of the cursor side link 1, and the other end is connected to the upper link 3 or head support link 2 located at point P2. Ba,
The distance between the points P3 and P2 increases and moves away from the drawing board as the head portion and the scale rise from the state of being in close contact with the drawing board. In addition, with respect to point P3 of the cursor side link 1, each part of the upper link 3 near point P2 and each part of the head support link 2 near point P2, as well as the point P2, are affected by the floating of the head and scale. Since the distance increases, the same effect can be achieved even if the other end of the tension member is connected to each part of the upper link 3 or the head support link 2 other than the point P2. Furthermore, in the same way, the distance between each part of the upper link 3 or the head support link 2 near point P2 increases as the head floats, with respect to each part of the cursor side link 1 near point P3. A bendable tension member can be provided. That is, theoretically, the line connecting the connecting portion of the cursor side link 1 of the tension member and the upper link 3 or the head support link 2 is at an angle formed by the line connecting points P1 and P2 of the upper link 2. On the other hand, if the connecting portion of the tensioning member is oriented upward rather than parallel, the connection portion of the tensioning member will increase as the head floats, and this increase will stretch the bent tensioning member into a tensioned state. It is possible to do this.

In the figure, reference numeral 4 denotes a tension member on the cursor side link 1 side. It is rotatably supported by. Reference numeral 7 denotes a tension member on the side of the head support link 2, which is rotatably attached to the head support link 2 with a rotation shaft 8. Both tension members 4 and 7 are provided with tension surfaces 4a and 7a that are perpendicular to the longitudinal direction thereof, and as shown in FIG. It is structured as follows. The tensioning member 7 has a connecting piece 7b with a step at the tip of the tensioning surface 7a, and a connecting shaft 9 planted on this connecting piece 7b is fitted into the connecting hole 10 of the tensioning member 4. Also,
The tension surface 4a of the tension member 4 has a circular arc surface 4b for bending.
are arranged in series, and the connecting hole 10 is formed into a long hole shape so as to provide a margin for this bending operation. Reference numeral 11 denotes a spring member that provides the tensioning member 7 with operability in the tensioning direction about the rotation axis 8 . Reference numeral 12 is a floating adjustment screw provided on the cursor side link 1 so as to come into contact with the end of the tension member 4, and is used to adjust the flying height of the head and scale by the tension members 4 and 7 as shown in FIG. It is provided to be adjusted.

On the other hand, the tension members 4 and 7 are attached to the upper link 3.
The bending actuating member 13 is placed at a position where it abuts near the bending portion of the
is provided. In the case of the embodiment, the bending actuating member 13
These include a cylindrical medium threaded piece 15 that is vertically movably supported by a support frame 14 fixed to the lower surface of the upper link 3, an adjustment screw member 16 screwed thereon, and an adjustment screw member 1.
Adjustment knob 17 for rotating 6, medium screw piece 15
and a loosening prevention spring 18 that applies an elastic force between the support frame 14 and the support frame 14. Additionally, reference numeral 15a denotes an axial guide groove provided in the internally threaded piece 15, into which the protrusion 14a of the support frame 14 is slidably fitted. 17a is an adjustment screw member 16 and an adjustment knob 17
This is a fixing screw that connects the two together. Therefore, in the case of the embodiment, the bending actuating member 13 is
By rotating 7, it is possible to variably adjust the amount of downward protrusion of the medium screw piece 15. That is, the adjustment knob 17, adjustment screw member 16, and medium screw piece 15 provided on the upper link 3 are as follows:
This constitutes a protrusion adjustment member according to the present invention that variably adjusts and sets the protrusion amount of the bending actuating member 13.

To explain the operating mode of the device according to the present invention having the above-mentioned configuration, assuming that the head portion and the scale are on the drawing surface in the state shown in FIG.
When this is raised, the head support link 2 moves upward approximately parallel to the cursor side link 1 by the parallel movement mechanism, and the distance between the rotation axes 6 and 8 of the tension members 4 and 7 increases. Accordingly, the arcuate surface 4b of the tension member 4 in the bent state rotates along the tension surface 7a of the other tension member 7, and when the head support link 2 floats up to the position shown in FIG. The tension surfaces 4a and 7a are in contact with each other, the rotation shafts 6 and 8 and the connecting shaft 9 are aligned, and the tension members 4 and 7 are in a tension state. Even if you release your hand from the head part in this state, the tension members 4 and 7
The scale can be maintained in a tensioned state, and the head and scale can be maintained in a floating state regardless of the load on the head. Now, when the head support link 2 is lifted upward about the pivot shaft 8 by holding the head part from the state shown in FIG. Since they are in contact with the tips, the tension members 4 and 7 are in a bent state similar to the state shown in the third figure. Therefore, if the head support link 2 is moved downward beyond the position shown in the second figure while in this bent state, the head portion and scale can be lowered to the position where they are in close contact with the drawing surface of FIG. 1. . Further, as shown in FIG. 3, if the internally threaded piece 15 of the bending actuating member 13 is set in a downwardly protruding position by means of the adjusting screw member 16, the tension members 4 and 7 can thereby be protruded. This will prevent it from becoming stretched, and the floating support effect can be eliminated. In FIG. 2, if the pivot point P ₃ or P ₄ of the lower link is configured to be movable, for example, as in the relationship between the tension member 4 and the swing member 5, the head support link 2 can be moved around the rotation axis. It is possible to rotate the head part significantly upward in the counterclockwise direction about a pivot point _P2 coaxial with the head part 8, and it is possible to support the head part in the upright state shown by the broken line.

As described above, according to the head floating support device according to the present invention, the head and the scale float approximately parallel to the drawing surface through the parallel movement mechanism having the upper link on the cursor side link. In a flexible parallel ruler formed by connecting head support links, one end of a tensioning member that is bent at the position where the head part and scale are in close contact with the drawing board, and has a bent part in the middle, which is in a tensioned state at the floating position. is connected to the cursor side link, and the other end is connected to a head support link or an upper link that separates as the head section floats, while abutting near the bent portion of the tension member at the floating position of the head section. Since the structure has a bending member that protrudes from the upper link and performs a bending action, the head part and scale can be supported in a floating state by the tensioning action of the tensioning member simply by floating the head part and scale. In addition, the tension member can be easily bent by the bending actuating member to return the head portion and the scale to the position in close contact with the drawing surface.
Therefore, even if the load on the head part changes depending on the inclination angle of the drawing board, there is an excellent effect in that there is no need to make any changes or adjustments to the supporting action, and the amount of protrusion of the bending member can be varied. With the configuration in which the upper link is provided with a protruding adjustment member that is adjusted and set, the third
As shown in the figure, when the bending actuating member is set to a downwardly protruding position by the protruding adjustment member, the tensioning member is thereby prevented from being in the tensioned state;
As a result, the floating support effect of the device of the present invention can be easily eliminated, making drafting work easier when the inclination angle of the drawing board is close to vertical and the load in the direction of the drawing board on the head is close to zero. effective.

[Brief explanation of the drawing]

Fig. 1 is a schematic front view showing a main part of an embodiment of the device of the present invention, Fig. 2 is a schematic front view showing its operating mode, and Fig. 3 is a schematic front view showing another operating mode of the main part. It is. 1...Cursor side link, 2...Head support link, 3...Upper link, 4, 7...Tension member,
9...Connection shaft, 10...Connection hole, 13...Bending actuation member.

Claims (1)

[Scope of utility model registration request] In a universal parallel ruler, a head support link is connected to a cursor side link via a parallel movement mechanism having an upper link so that the head part and scale float approximately parallel to the drawing surface. Connects one end of the tensioning member, which has a bent part in the middle, to the cursor side link, and connects the other end to the floating position of the head. A bending actuating member is provided protruding from the upper link and connects to the head support link or the upper link which separates as the head part moves away, and which performs the bending operation by contacting the vicinity of the bending part of the tension member in the floating position of the head part, A head floating support device for a universal parallel ruler, comprising a protrusion adjustment member provided on an upper link to variably adjust and set the protrusion amount of the bending member.