JPH0114467Y2 - - 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, reference numeral 3 denotes 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 to each other so that they can rotate 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 motion mechanism.
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 moves from the position where it contacts the drawing board surface in Fig. 1 to the floating position of the head part and scale as shown in Fig. 2. During this period, for example, the distance between point P ₃ of the cursor side link 1 and point P 2 of the head support link 2 or the upper link ₃ increases, so that a bendable tension that is in tension at the floating position is created between these two points. If the member is provided, the head part and scale can be supported in the floating position, and by being bent, the head part and the scale 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 as the head portion and scale rise from the state of being in close contact with the drawing board. Also, point P of link 1 on the cursor side
3, each part of the upper link 3 near the point P2 and each part of the head support link 2 near the point P2 are connected to the point P2.
2, the distance increases as the head and scale float, so the same effect will occur even if the other end of the tension member is connected to any part of the upper link 3 or head support link 2 other than point P2. be. Furthermore, similarly, for each point near the point P3 of the cursor side link 1, the point P of the upper link 3 or the head support link 2 is
Since each part near 2 also increases in distance as the head part floats, a bendable tension member can be provided between these parts. 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 tension member is oriented upward rather than parallel, the connection portion of the tension member will increase as the head floats.

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. As shown in FIG. 3, the tension member 7 is provided with a connecting piece 7b with a step at the tip of the tension surface 7a, and the connecting shaft 9 planted on this connects to the connecting hole of the tension member 4. 10 is fitted. Further, the tension surface 4a of the tension member 4 is provided with a circular arc surface 4b for bending, and the connection hole 10
is configured in the shape of a long hole. 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, a bending actuating member 13 is provided on the upper link 3 at a position that abuts near the bent portions of the tension members 4 and 7. The bending actuating member 13 is a guide member 14
It is configured to reciprocate between the position shown by the solid line in FIG. 1 and the protruding position shown by the broken line in FIG. They face each other near the bent portions of members 4 and 7. In the case of the embodiment, a return spring 15 is provided between the guide member 14 and the bending member 13, and the spring force is always applied to return the bending member 13 to the return position shown by the solid line. Further, the bending actuating member 13 is provided with a guide groove 13a along the protrusion direction, into which the protrusion 14a of the guide member 14 fits, as shown in FIG.
By engaging the protrusion 14a with the protrusion 14a, the bending actuating member 13 can be locked in the protruding position.

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
maintains a tensioned state, and maintains the head and scale in a floating state regardless of the load on the head. Here, when the bending actuating member 13 provided on the upper link 3 is pressed downward against the return spring 15,
The tension members 4, 7 are bent around the connecting shaft 9, the contact between the tension surfaces 4a, 7a is removed, and the arcuate surface 4b and the tension surface 7a are in a bendable state, as shown in the first figure. With the bending of the tension members 4 and 7, the head support link 2 can be lowered to a position where it contacts the drawing surface. Further, as shown by the broken line in FIG. 1, if the bending member 13 is locked in the protruding position, the tension members 4 and 7 will be maintained in the bent state even if the head support link 2 is moved upward. It also becomes possible to use the floating support device in a released state.

In the state shown 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 is attached to a pivot point coaxial with the rotation axis 8.
The bending actuating member 13 can be rotated counterclockwise around _P2 , thereby returning the bending actuating member 13 to the return position.
If the tension members 4 and 7 are brought into contact with each other and the tension members 4 and 7 are slightly bent about the connecting shaft 9, the tension surface 7a and the arcuate surface 4b will be in contact with each other. can be easily returned to the state.

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. The structure is such that a bending member that performs a bending action is protruded from the upper link, and the head portion and scale can be supported by the tensioning action of the tensioning member. Even if the load on the head changes depending on the inclination angle, it has an excellent effect that does not require any changes or adjustments to its supporting action.
In addition, since the tension member can be easily bent by the bending actuating member and the head portion can be returned to the position where it is in close contact with the drawing surface, it has the effect of making drafting work easier and has many practical benefits. It is.

[Brief explanation of the drawing]

Fig. 1 is a schematic front view showing the main parts of an embodiment of the device of the present invention, Fig. 2 is a schematic front view showing its operating mode, Fig. 3 is a perspective view of the main parts, and Fig. 4 is a schematic front view showing the main parts of the device. It is an exploded explanatory view of other important parts. 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 state of the head part. A bending actuating member is provided on the upper link so as to be freely protrusive and connects to the head support link or the upper link which separates as the head part moves, and which performs a bending action by contacting the vicinity of the bending part of the tension member in the floating position of the head part. A floating support device for the head part of a universal parallel ruler.