JPH075792U - Proportional compass - Google Patents

Abstract

(57) [Summary] (Correction) [Purpose] Use a proportional compass to prevent errors during drawing work. [Composition] A groove is provided at the center of the upper and lower two supporting legs 3 and 4,
The pedestals 12 and 13 are attached to the center, and the pinion 9 is attached to the center of the pedestals 12 and 13. A rack is attached to the supporting legs 4 and 3, teeth are engaged with each other, a knob 5 with a dial is provided on the upper part of the central shaft, and a thumbscrew 6 is provided on the lower part, and tightened from below. When the thumbscrew 6 is loosened and the knob 5 is rotated, the teeth of the pinion mesh with the rack, and the mounts 12, 13 move while sliding in the grooves of the supporting legs 4, 3. Obtain a predetermined proportional dimension and turn the thumbscrew 6 clockwise to tighten it. In order to make the measurement more accurate, the upper support leg 4 is engraved with a scale indicating the magnification of several lines, and the gantry 12 at the center of the upper support leg is provided with one line scale to match the scale on the upper support leg 4. If the upper and lower support legs are opened and the original size is obtained using the short left hand pointer, the right hand pointer opening will be the required proportional dimension.

Description

[Detailed description of the device]

A proportional compass is one in which the center point moves and the left and right dimensions are proportional to each other. The upper support leg with the upper and lower support legs and the upper and lower support legs with the central axis are provided with a pedestal with the central axis. The center shaft can be moved while sliding inside the supporting leg. Tighten the upper and lower support legs by attaching teeth. While adjusting the tightening amount with the thumbscrew, align the upper and lower support legs in parallel and rotate the center axis to move them to any position, and open the upper and lower support legs to obtain the dimensions.

[0002]

[Industrial applications]

 The present invention relates to a proportional compass for a drafting machine.

[Prior art]

A conventional proportional compass is one in which the upper and lower ends of the proportional compass are aligned and the central axis is pushed to move it to an arbitrary position. After the movement, the upper and lower support legs are opened and the central axis is not fixed because the central axis is not fixed when the dimensions are obtained. Accurate proportional dimensions could not be obtained due to the unevenness of the tips due to slight movements of the vertical support legs. Also, there is no catch on the pedestal during the work, so it goes wrong.

[Problems to be solved by the device]

When the central shaft is pushed to an arbitrary position and the upper and lower support legs are opened, the upper set screw is loosened and the upper and lower support legs do not catch the central axis, so the upper and lower support legs move in and out, and the correct proportion is obtained. Do not enter or exit because the dimensions cannot be obtained. When the setscrew comes loose a little, the upper and lower support legs become uneven during work, so it is necessary to attach a hook.

[Means for Solving the Problems]

FIG. 4. Align the tips of the upper and lower support legs of 4.3 in parallel and attach a gear as shown in FIG. 4 to the 9 center axes of 2 and attach a rack to one side of 4.3 of the upper and lower support legs of FIG. 5 and rotate the center axis of FIG. A proportional dimension can be obtained by the scale and the numbers of the dial 7 on the upper part of the central shaft 9 of FIG. 4 which can be moved to any position by meshing with the teeth of. The top and bottom support legs of 4.3 are opened along the teeth of the central axis 9 and the teeth of the pinion 9 and the teeth of the rack 3.4 mesh with each other, so there is no slight movement of 4.3 of the tip 3 and it is accurate. The dimensions are obtained. Also, by rotating the 6 butterfly screw in Fig. 3 and fixing the whole, the dimensions do not change during operation.

[Work]

Grooves are provided on the upper and lower support legs shown in FIG. The center axis 2-9 is on the moving 6-12.13 pedestal, and the pedestal slides in the center of the fulcrum, so the center axis is at the center of the fulcrum. There is no meshing with the gear and 4.3 teeth of 8. Since the upper and lower support legs open along the rack of the central axis on the rack of 12.13, the central shaft 9 does not move slightly and the rack teeth of the upper and lower support legs mesh with each other. As a result, an arbitrary size can be obtained without slipping.

【Example】

In order to move the central axis by turning the butterfly screw 6 in FIG. 4 counterclockwise to loosen the whole and obtaining the enlarged dimension of the scale 18. The central axis for turning the knob 5 is on the base 12, and the pinion teeth 4.3 on the central axis are aligned in parallel. Therefore, the center of the supporting leg is placed on the base 12 and the pinion 9 meshes with the teeth of the rack 4.3. Proceed and stop at the desired scale, lightly turn the 6-screw screw to the right and tighten it. Spread out the short tip portion 14.15 of Fig. 3 and measure the dimension. Find the wide dimension of the long tip portion 16.17.

[Effect of device]

The central shaft 9 is located in the center groove of the pedestal 8 in the center groove of the upper and lower supporting legs 11.8. The central shaft 9 is located at the center of the central shaft 9 and has 9 teeth of the pinion 6; When 3 knobs 5 are engaged, dial 7 located on the central axis rides on pedestal 12 and the top and bottom are engaged with rack 4.3 teeth to advance and stop at the desired scale. Lightly turn to the right and tighten, and open the shorter tip 14.15 in Fig. 3 and measure the dimensions. Find the wide dimension of the long tip 16.17.

[Effect of device]

The central shaft 9 is located in the center groove of the pedestal 8 in the center groove of the upper and lower supporting legs 11.8, and the central shaft 9 is located at the center of the racks 12.6 to 13. When the knob 3 is meshed with 3, the dial 7 located on the central axis moves on the pedestal 12 while sliding on the upper and lower support legs, and the 4.3 teeth of the pinion 9 and the rack teeth 8 are hooked. There is no slight movement, so if you tighten the 6 thumbscrew, there will be no deviation during the work and look at the dial 7 scale. Turn knob 5 to make fine measurements.

[Brief description of drawings]

FIG. 1 is a plan view.

2 is a side view 7 is a dial 8 is an upper support leg 9 is a pinion spindle 11 is a lower support leg 12 is an upper mount 13 is a lower mount

[Fig. 3] Plan view of the upper and lower supporting legs when they are opened.

[Fig. 4] Large sectional view of the central part 6 shows a butterfly screw

FIG. 5 shows the engagement of the rack and pinion gears on the upper and lower support legs.

[Fig. 6] Accessory diagram 9 Pinion 12 Upper mount 13 Lower mount 6 Thumbscrew

[Fig. 7] Accessory diagram 5 Knob 7 Dial
13 is a lower mount 11 is a lower support leg 3 is a lower rack 8 is an upper support leg 4 is an upper rack

[Fig. 8] Assembly of upper mount [Fig. 12] Upper mount

Claims (1)

[Scope of utility model registration request] 1. An arbitrary proportional dimension can be obtained by engraving a rack tooth on one side of a supporting leg of a proportional compass and moving the central axis while rotating the central axis with a pinion on the central axis. Even if the set screw is loosened, the pinion and the rack stop the upper and lower support legs from moving in and out, so if the support leg is widened, the pinion will engage with the rack and stop the support leg from moving in and out. It is a proportional compass that can be laterally determined by the movement of the central axis with a rack and a gear.