JPH0436953Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a stopper mechanism for a balance weight on a vertical rail of a rail type universal parallel ruler.

[Conventional technology]

As shown in Figure 5, the rail type flexible parallel ruler has a horizontal rail 4 on the upper edge of the drawing board 2, which can be set at any inclination angle between horizontal and perpendicular to the floor. One end of a vertical rail 6 is slidably connected to the horizontal rail 4 via a horizontal cursor. Lower rail surface 6b of vertical rail 6,
6b', 6c, and 6d are in contact with rollers rotatably supported by the vertical cursor 8, and the vertical cursor 8 is movably connected to the lower part of the vertical rail 6 via the rollers. A balance weight 12 is disposed in a weight insertion space 10 above the vertical rail 6 so as to be freely movable along the longitudinal direction of the vertical rail 6. A head 14 is attached to the vertical cursor 6, and a straight edge 18, 20 is attached to a ruler mounting plate 16 of the head 14.
is installed. The tail end of the vertical rail 6 is
It is mounted movably on the drawing board 2 via tail rollers 22. Covers 24 and 26 made of plastic sticks are fixed to both ends of the vertical rail 6, and a wire rope 32 is stretched between rope pulleys 28 and 30 rotatably supported by the covers 24 and 26. weight 12
and the vertical cursor 8 are connected to each other so as to move in opposite directions along the vertical rail 6. The cover 24 has its peripheral edge 24a in contact with the open end of the tail end of the rail 6, and the connecting portion 24b protruding from the cover 24 connects to the bottom wall 6a of the weight insertion space 10 with two bolts. It is fixed by a screw 34 consisting of: A notch is formed in the intermediate portion of the connecting portion 24b, and a rope pulley 28 is disposed in the notch. A support shaft 36 rotatably fitted to the center of the pulley 28 is connected to a groove 38 formed in the connecting portion 24b behind the screw 34.
It is inserted and placed in. The structure of the cover 26 is also the same as that of the cover 24. As is clear from FIG. 4, a portion of the surface of the pulley 28 projects from the projecting end of the connecting portion 24b of the cover 24 toward the center of the vertical rail 6 by a predetermined distance. Stopper means for stopping the movement of the vertical cursor 8 are provided at appropriate positions at both ends of the vertical rail 6, so that when the vertical cursor 8 is moved along the vertical rail 6, the vertical cursor 8 moves in conjunction with the vertical cursor 8. A limit of movement of the vertical cursor 8 along the vertical rail 6 is set so that the balance weight 12 moving in the opposite direction does not collide with the surfaces of the pulleys 28 and 30. Usually, the drawing board 2 is set to be inclined with respect to the floor surface. Therefore, when the drafter releases the braking force of the vertical cursor 8 against the vertical rail 6 and releases the hand from the head 14, the vertical cursor 8 is moved from the drawing board 2 due to the weight of the head 14 and the vertical cursor 8. Due to the inclination, the head 1 tends to fall suddenly towards the tail end of the vertical rail 6, but due to the balancing action of the balance weight 12, which is set to have the same weight as the total weight of the head 14 and the vertical cursor 8, the head 1
4 remains stationary on the drawing board 2. In this state, the drawing person is configured to be able to manually move the head 14 to any desired position on the drawing board 2 with a light force. The rails 4, 6 are made of aluminum.

[Problem that the invention attempts to solve]

In the above configuration, when the wire rope 32 is cut during drafting, the balance weight 12 suddenly falls along the vertical rail 6 due to its weight, and collides only with the surface of the pulley 28 on the tail end side of the vertical rail 6. . When the balance weight 12 collides with the pulley 28, the support shaft 36 is pressurized in the direction of the arrow in FIG. 4, and the support shaft 36 presses the wall surface of the groove 38 of the connecting portion 24b in the direction of the arrow. Due to this pressing force, the connecting portion 24
A load is applied to b in the direction in which it is pulled against the screw 34, and this load causes the connecting portion 2 of the cover 24 to
There was a defect in which the concave groove forming portion of 4b was broken.
To prevent cover 24 from cracking, remove cover 2
4 may be made of metal like the vertical rail 6 and the screw 34, but in this case, the weight of the cover increases. The purpose of the present invention is to prevent the cover 24 from being destroyed even if the balance weight collides with it.

[Means to solve problems]

In order to achieve the above purpose, the present invention has developed vertical rail 6.
A cover 40 is brought into contact with the tail end of the vertical rail 6, and the connecting portion 40b protruding from the cover 40 is connected to the bottom wall 6 of the vertical rail 6.
A screw 34 is fixed to the connecting portion 4 of the cover 40.
0b, the rope pulley 2 is inserted into a concave groove 44 formed closer to the tail end of the vertical rail 6 than the screw 34 fixing part.
8 support shafts 36 are arranged to rotatably support the rope pulley 28 on the connecting portion 40b, and the rope 32 is hung between the rope pulley 28 and a rope pulley 30 disposed on one end side of the vertical rail 6. , a balance weight 1 in the weight insertion space 10 formed in the vertical rail 6 on the rope 32;
2 and a vertical cursor 8 movably connected to the vertical rail 6 are connected to each other so as to move in opposite directions along the vertical rail 6, when the rope 32 is cut, the tail side of the vertical rail 6 The tip of the connecting portion 40b of the cover 40 is arranged at a position that prevents the balance weight 12 from colliding only with the rope pulley 28, and the cover 40 is made of plastic.

[Effect]

In the above configuration, when the rope 32 hung between the rope pulleys 28 and 30 arranged at both ends of the vertical rail 6 breaks and the balance weight 12 suddenly runs toward the tail of the vertical rail 6, the balance weight 12 The screws 34, 34 that are fixed to the top of the connecting portion 40b of the cover 40 and fixed to the bottom wall 6a of the vertical rail 6 are subjected to a load due to the collision, and the connecting portion 4 of the cover 40 is
The collision load from the balance weight 12 is not applied to the concave groove forming portion 0b.

〔Example〕

The configuration of the present invention will be described below with reference to embodiments shown in the accompanying drawings.

In FIG. 1 and FIG. 3, 40 is a plastic cover whose peripheral edge 40a is in contact with the tail end of the vertical rail 6, and a connecting portion 40b is protruded from this, and a pulley is arranged on the connecting portion 40b. A notch is formed for this purpose. Screws 34, 34 made of bolts are inserted into holes transparently provided in the bottom wall 6a of the tail portion of the vertical rail 6, and the screws 34, 34
The cover 40 is fixed to the tail end of the vertical rail 6 by screwing into screw holes 42, 42 formed in the vertical rail 6. A notch is formed in a portion of the bottom wall 6a located directly below the notch, and rope pulleys 28 are disposed in these notches, and a rope pulley 28 is rotatably inserted into the center hole of the pulley 28 via a ball bearing. Portions near both ends of the supporting shaft 36 to be fitted are fitted into grooves 44 formed in the connecting portion 40b. Tip stopper surface 40 of the connecting portion 40b
c and 40c protrude from the surface of the pulley 28 toward the center of the vertical rail 6 by a predetermined distance. The other configuration of the vertical rail 6 is the same as the conventional configuration.

In the configuration described above, when the wire rope 32 breaks and the balance weight 12 suddenly runs in the falling direction along the vertical rail 6 due to its weight, the balance weight 12 moves to the connecting portion 40b of the cover 40.
collides with the stopper surfaces 40c, 40c, the impact against the stopper surfaces 40c, 40c is applied to the screw 34, and as in the conventional case, the concave groove 44 of the connecting portion 40b
No tensile load is applied only to the forming part,
Therefore, the cover 40 is not destroyed by a collision with the balance weight 12.

〔effect〕

As mentioned above, in this invention, when the balance weight suddenly moves, the collision load with the balance weight is received by the stopper surface of the connecting part protruding from the cover, so that the balance weight does not collide only with the pulley that engages with the cover. , it is possible to prevent a tensile load from being applied to the concave groove forming portion that holds the pulley support shaft of the plastic cover, and there is an effect that the cover can be prevented from being destroyed.

[Brief explanation of drawings]

Fig. 1 is a side sectional view, Fig. 2 is a plan sectional view, Fig. 3 is a plane sectional view taken along line A-A, Fig. 4 is a side sectional view of the conventional plan, Fig. 5 is the same plan view, Fig. 6 is an explanatory diagram. 2... Drawing board, 4... Horizontal rail, 6... Vertical rail, 8... Vertical cursor, 10... Weight insertion space, 12... Balance weight, 14... Head, 16... Ruler mounting plate, 18, 20... Straight ruler, 22... Tail roller, 24, 26... Cover,
24b... Connection portion, 28, 30... Rope pulley, 32... Wire rope, 34... Screw, 36
... Support shaft, 38 ... Concave groove, 40 ... Cover, 40
a...Peripheral edge, 40b...Connecting portion, 40c...Stopper surface, 42...Threaded hole, 44...Concave groove.

Claims (1)

[Scope of utility model registration request] A cover 40 is brought into contact with the tail end of the vertical rail 6, a connecting portion 40b protruding from the cover 40 is fixed with a screw 34 to the bottom wall 6a of the vertical rail 6, and the cover 4
The support shaft 36 of the rope pulley 28 is disposed in a concave groove 44 formed closer to the tail end of the vertical rail 6 than the screw 34 fixing part in the connecting part 40b of 0, so that the rope pulley 28 can be freely rotated in the connecting part 40b. A rope 32 is hung between the rope pulley 28 and a rope pulley 30 disposed at one end of the vertical rail 6, and a balance weight in the weight insertion space 10 formed in the vertical rail 6 is attached to the rope 32. 12 and a vertical cursor 8 movably connected to the vertical rail 6 are connected to each other so as to move in opposite directions along the vertical rail 6, when the rope 32 is cut, the tail side of the vertical rail 6 In the vertical rail of the universal parallel ruler, the tip of the connecting part 40b of the cover 40 is arranged at a position that prevents the balance weight 12 from colliding only with the rope pulley 28, and the cover 40 is made of plastic. Stopper mechanism for balance weight.