JPH0323636Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a rotary cam limit switch.

In a conventional rotary cam limit switch, as shown in FIG. 1, each limit switch 3 operated by a cam 2 provided on a camshaft 1 is attached to a bracket 4 fixed to the machine body. Therefore, the mutual spacing between the limit switches 3 becomes larger and the camshaft 1 becomes longer, which requires more materials and man-hours to manufacture, and the overall external dimensions of the rotary cam limit switch become larger, making it difficult for machinery, e.g. It was inconvenient to equip the press.

In order to solve this problem, the limit switches are stacked parallel to the camshaft and connected to each other with long bolts, and then these limit switches are attached to one common bracket fixed to the fuselage. It is possible that

However, there are variations in the positions at which the limit switches are turned on and off by the cam, and in order to eliminate the effects of these variations and turn each limit switch on and off at the predetermined timing, it is necessary to adjust the position of each limit switch. It is necessary to individually adjust the position of the limit switch with respect to the cam, and the limit switch mounting structure described above does not allow such individual position adjustment of the limit switch.

SUMMARY OF THE INVENTION An object of the present invention is to provide a rotary cam limit switch in which the distance between limit switches can be made extremely small, the camshaft can be shortened, and the position of each limit switch can be adjusted individually with respect to the cam.

An embodiment of the present invention will be described below with reference to the accompanying drawings.

FIG. 2 shows a rotary cam limit switch 5 according to this embodiment. A camshaft 1 is rotatably supported on a body 6 of the rotary cam limit switch 5, and a large number of cams 2 are provided on the camshaft 1 at equal intervals. In this embodiment, two cams 2 form a set, and by mutually rotating the two cams 2 and changing their positional relationship as necessary, the peaks,
The rotation angle of the valley can be adjusted as desired.

As shown in FIG. 3, a plurality of brackets 4 are arranged in parallel to the camshaft 1 on the body 6, and these brackets 4 are attached to the body 6 with screws 13. each bracket 4
has a mounting plate part 7 extending perpendicularly to the camshaft 1 at a position spaced from the camshaft 1, and both side surfaces of the mounting plate part 7 face in a direction parallel to the camshaft 1. There is. Limit switches 3 are attached to these sides with spring pins 8.

Specifically, the mounting plate part 7 and the limit switch 3 applied to both sides of the mounting plate part 7 have two mounting holes (upper and lower) formed therein, and the spring pin 8 is inserted into these mounting holes. This allows the two limit switches 3 to be attached to the mounting plate 7.
attached to both sides. A strip-shaped thin plate 9 is wound around the outer periphery of the pair of limit switches 3, including the mounting plate 7, and both ends of the thin plate 9 are attached to the mounting plate 7 on the lower side of the limit switch 3 with screws and nuts 10. is combined with As a result, the limit switch 3 is surrounded by the thin plate 9, so that the limit switch 3 will not fall off from the spring pin 8.

In this way, each limit switch 3
are attached to the mounting plate portion 7 of the bracket 4, and these limit switches 3 are arranged opposite to the respective cams 2.

In the above, the screw 13, which is screwed into the screw hole of the body 6 in order to attach the bracket 4 to the body 6, is loosely fitted into the hole provided in the bracket 4, and therefore the screw 13 is loosely fitted in the hole provided in the bracket 4. The position of the bracket 4 can be moved. This direction of movement is any direction as long as it is parallel to the plane of the paper in FIG. The position of the bracket 4 can be adjusted in the direction of rotation about an axis parallel to the cam 2, and thus the position of the limit switch 3 relative to the cam 2 can also be adjusted.

In this embodiment, a transmitting plate 1 is provided at one end of the camshaft 1 in the shape of a disk and has concavities and convexities of a constant pitch on the outer circumference.
1 is fixed, and this transmitter plate 1 is fixed to the fuselage 6.
A pulse oscillator 12 is installed across the outer circumferential portion of the camshaft 1 to electrically detect the irregularities thereof, thereby making it possible to determine the exact rotation angle of the camshaft 1.

Next, the effect will be explained.

When the camshaft 1 rotates, the peaks and valleys of the cam 2 turn the limit switch 3 on and off.
The off electrical signal controls the operation of a machine such as a press equipped with the rotary cam limit switch 5.

As shown in FIG. 4, the limit switch 3 has a roller 1 that contacts the cam 2 at its tip, similar to the well-known one.
4, the lever 15 is swung around its lower end by the cam 2, and the operating member 16 moves forward and backward, thereby turning on the limit switch 3.
Works off. The position where the limit switch 3 turns on or turns off varies among each limit switch 3, and therefore,
If each limit switch 3 is simply attached to the mounting plate 7 of the bracket 4 and placed on the fuselage 6, the limit switch 3 will be turned on or off at a predetermined timing when the rotation angle of the camshaft 1 reaches a predetermined angle. This results in an error in the control timing of the machine.

Therefore, in this embodiment, before tightening the screws 13, for each bracket 4,
Perform the position adjustment work described above.

That is, each bracket 4 is connected to the camshaft 1.
By moving the bracket 4 forward and backward, it is possible to adjust the ON or OFF position of the limit switch 3 for each bracket 4, and also move the bracket 4 around an axis parallel to the direction in which the mounting plate 7 extends. If the limit switches 3 are rotated as shown in FIG.
Since there is a difference in the distance from the camshaft 1 between the two limit switches 3, the ON or OFF positions of these pair of limit switches 3 can be adjusted, and each limit switch 3 can be individually positioned relative to the cam 2. This can be adjusted.

After the above adjustment work, each bracket 4 is fixed to the fuselage 6 by tightening the screws 13.
Each limit switch 13 is turned on or off at a predetermined timing.

Further, according to this embodiment, each limit switch 3 is arranged in a direction parallel to the camshaft 1,
What is placed between these limit switches 3 is only the mounting plate 7 of the bracket 4 and the strip-shaped thin plate 9, which are thin, and in order to provide the inclination angle θ, the two adjacent Since the gaps provided between the limit switches 3 attached to the individual brackets 4 do not need to be so large, the limit switches 3 can be arranged in a manner parallel to the camshaft 1 in a sufficiently closely packed state. Therefore, even if there are a large number of limit switches 3, the length of the camshaft 1 can be shortened, and the rotary cam limit switch 5 can be made smaller.

Furthermore, according to the present embodiment, a certain limit switch 3 can be removed from the aircraft 6 due to maintenance work or a malfunction.
If it becomes necessary to remove the limit switch 3 from the fuselage 6, you only need to remove the bracket 4 to which the limit switch 3 is attached, and the other brackets 4 and limit switch 3 can be left in the fuselage 6. The work can be done easily because only the parts need to be removed.

As described above, according to the present invention, a large number of limit switches can be arranged parallel to the camshaft with extremely small intervals, so the camshaft can be shortened, and the rotary cam limit switch as a whole can be downsized. Even if the number of cams increases, it can be installed in the specified space of a machine such as a press, and
It is easy to remove and remove each limit switch, and since each limit switch can be adjusted individually relative to the cam, these limit switches can be turned on and off at precisely the predetermined timing. It becomes like this.

[Brief explanation of the drawing]

Figure 1 is a partial cross-sectional plan view showing a conventional example;
The figure is a partially sectional plan view showing an embodiment of the present invention.
Fig. 3 is a partially cross-sectional front view taken in the direction of the arrow in Fig. 2, Fig. 4 is a side view showing how the limit switch is turned on and off by a cam, and Fig. 5 shows the limit switch attached to the mounting plate of the same bracket. FIG. 3 is a plan view showing position adjustment of a pair of limit switches with respect to a cam. 1...Cam shaft, 2...Cam, 3...Limit switch, 4...Bracket, 5...Rotary cam limit switch, 6...Body, 7...Mounting plate, 8...Spring pin, 9... Thin plate.

Claims (1)

[Claims for Utility Model Registration] A rotary cam limit switch having a large number of cams provided at equal intervals on a camshaft and a large number of limit switches arranged in positions corresponding to the cams, each of which is connected to the camshaft from the camshaft. The camshaft has a mounting plate extending in a direction perpendicular to the camshaft at a spaced apart position, and is arranged parallel to the camshaft and is adjustable in position in the forward and backward direction with respect to the camshaft. A plurality of brackets are attached to the fuselage so that their positions can be freely adjusted in a rotational direction about an axis parallel to the extending direction of the mounting plate, and a plurality of brackets are inserted through the mounting plate of the bracket, and the bracket is inserted through the mounting plate of the bracket, and a spring pin with the limit switch attached to both sides facing in a direction parallel to the camshaft;
A strip-shaped thin plate that surrounds the outer periphery of the pair of limit switches including the mounting plate portion, and that both ends thereof are connected to the mounting plate portion on the lower side of the pair of limit switches. A rotary cam limit switch featuring: