JPH0447879Y2 - - Google Patents

Description

[Detailed explanation of the idea] 〔Technical field〕 This invention relates to a photoelectric switch.

[Background technology]

The photoelectric switch is equipped with a sensitivity adjustment volume. Sensitivity is adjusted by rotating a rotating shaft provided on this volume. This axis is adapted to rotate through more than one revolution to facilitate sensitivity setting. However, with conventional photoelectric switches, the person who sets them does not know how many times they have been rotated, and when using multiple switches, it is difficult to set each switch to the same sensitivity.

[Purpose of invention]

In view of the above circumstances, the workability of sensitivity adjustment has been improved, and not only has it become easier to set the same sensitivity for each, but the means for displaying the number of rotations of the rotation axis of the sensitivity adjustment volume that is provided for this purpose has been made compact. , and does not require a large installation space.
To provide a highly practical photoelectric switch that can easily improve the positional accuracy of the sign of the rotation speed display means and also easily respond to changes in the rotation speed of the sensitivity adjustment volume and the amount of movement of the sign per rotation. The task is to do so.

[Disclosure of invention]

In order to achieve the above object, this invention provides a photoelectric switch that is equipped with a sensitivity adjustment volume, the sensitivity is adjusted by rotating a rotating shaft provided on the volume, and the upper limit of the rotation is one rotation or more.
A fixed tooth, a movable tooth, and an eccentric cam are fitted into the rotating shaft in this order, and the eccentric cam and the rotating shaft are connected by a connecting rod so that they interlock, and the rotation of the fixed tooth is stopped. At the same time, external teeth are formed on the side facing the movable teeth, and the lower part of the eccentric cam is a cam part that rotates eccentrically from the axis of the rotating shaft. In addition, internal teeth that engage with the external teeth of the fixed teeth are formed on the side facing the fixed teeth with a larger number of teeth than the external teeth, and a mark is attached to the outer periphery. and the position of the sign is shifted in accordance with the rotation of the rotation axis,
The portion surrounding the movable tooth is provided with a scale that indicates the number of rotations within the range of movement of the mark, and the scale and the mark serve as a display means for displaying the number of revolutions of the rotating shaft. The gist is a photoelectric switch.

This will be explained in detail below based on the drawings showing one embodiment thereof.

As shown in FIGS. 1 to 3, this photoelectric switch is equipped with a sensitivity adjustment volume 1 and a display means 2. As shown in FIGS. The sensitivity adjustment volume 1 is provided with a rotating shaft 1a having a groove 1b formed at its tip into which a flathead screwdriver or the like is inserted. Sensitivity is adjusted by rotating this rotating shaft 1a. This rotating shaft 1a is adapted to rotate over one rotation or more in order to facilitate setting of sensitivity. In this embodiment, it rotates three times. The sensitivity adjustment volume 1 is attached to one 3 of two electronic component blocks 3 and 4 (electronic components not shown). The other electronic component block 4 is provided with light emitting diodes 15, 15 for display. The two electronic component blocks 3 and 4 are each fixed by both an optical tube 5 and a connector body 6, and are housed in a body case 7 that is combined with the optical tube. There is. The main case 7 has a notch 8 on the top surface.
A nameplate 9 is attached to cover the notch 8.

A fixed tooth 10, a movable tooth 11, and an eccentric cam 12 are fitted into the rotating shaft 1a. fixed teeth 10
As shown in FIGS. 4a and 4b, an insertion hole 10a is formed in the center for passing the rotating shaft 1a of the sensitivity adjustment volume, and a recess 10b for receiving the movable tooth 11 is formed on the side facing the movable tooth. has been done.
In this recess 10b, external teeth 10c having an involute tooth profile and having 11 teeth are formed. As shown in FIGS. 5a, b, and c, the eccentric cam 12 has an insertion hole 12a formed in the center through which the rotating shaft 1a of the sensitivity adjustment volume 1 passes, and the upper part thereof is coaxial with the central axis of the insertion hole 12a. The flange portion 12b is a flange portion 12b, and the lower portion thereof is a cam portion 12c eccentric from the central axis of the insertion hole 12a. A notch 12d is formed around the insertion hole 12a on the upper surface of the flange portion 12c, into which a connecting rod 13 for connecting to the rotating shaft 1a is fitted. As shown in FIGS. 6a and 6b, the movable tooth 11 is formed with a hole 11a that fits into the cam portion 12b of the eccentric cam, and has 12 teeth that mesh with the external tooth 10c of the fixed tooth. Internal teeth 11b having an involute tooth profile are formed. In this way, the internal tooth 11 of the movable tooth
The number of teeth b is one more than the number of external teeth 10c of fixed teeth. On the outer periphery of the upper surface of this movable tooth,
A sign 16 is attached.

The eccentric cam 12 fitted into the rotating shaft 1a has its notch 12d aligned with the groove 11b at the tip of the rotating shaft 1a, and the connecting rod 13 is fitted into the notch and the groove to rotate as the rotating shaft 1a rotates. It is supposed to rotate. The fixed tooth 10 is fixed so as not to rotate due to rotation of the rotating shaft 1a. The eccentric cam 1 is rotated by the rotation of the rotating shaft 1a.
2 is moved, the movable tooth 11 is also moved. Along with this, the sign 16 is also moved. A nameplate 9 attached to the main body case is provided with a window 9a, through which the movable teeth 11, the eccentric cam 12, and the tip of the rotating shaft 1a are exposed. A part of the periphery of the window 9a, that is, a part surrounding the movable teeth, is provided with a scale indicating the number of revolutions within the range in which the marker 16 moves.

Next, with reference to FIG. 11, the movement of the sign accompanying the rotation of the rotating shaft 1a will be explained. In the figure, 20 is the center of the rotating shaft, and 21 is the center of the cam portion.

As shown in the figure, the rotation axis 1 of the sensitivity adjustment volume
When a is rotated in the direction of arrow X in the figure, the cam portion 12c of the eccentric cam moves eccentrically with this rotation.
Along with this movement, the movable tooth 11 moves to its inner tooth 11b.
It moves freely while meshing with the external teeth 10c of the fixed teeth 10. The inner teeth 11b and the outer teeth 10c are brought together one by one. That is, the external tooth b is placed in the recess B between the internal teeth, the external tooth c is placed in the recess C, and the external tooth d is placed in the recess D.
It's like I'm stuck in it. In this way, when the rotating shaft 1a rotates once, the external tooth a
will fit into the recess L. Comparing this state with the state shown in Fig. 7, the movable tooth 11 moves by one tooth of the internal tooth 11b, that is, 360° x 1/12 = 30°.
It will be out of alignment. In this way, the rotating shaft 1a
The movable tooth 11 shifts by 30° per rotation. Along with this, the position of the marker 16 attached to the outer circumference of the movable tooth also shifts by 30 degrees. In this embodiment, the rotating shaft 1a rotates three times, so the marker 16
The position of is shifted by a total of 90°. The scale 14 attached to the nameplate 9 is attached at every 30° within the range of movement of the sign 16. Therefore, by looking at the position of the mark 16 with respect to the scale 14, it can be seen how many revolutions the rotation axis 1a has made. That is, the scale 14 and the mark 16 serve as display means for displaying the number of rotations of the rotating shaft.

As we have seen above, this photoelectric switch
Since a display means is provided to display the rotation speed of the rotation shaft of the sensitivity adjustment volume, the rotation speed of the rotation shaft can be known. Conventionally, when using multiple devices, if you finished setting the sensitivity of one item and tried to set the sensitivity of another item, you would have to readjust the other item from the beginning. According to , since the number of revolutions of the rotating shaft is known, adjustments can be made within a range of one revolution, making it easy to set each sensitivity to the same.

The photoelectric switch according to this invention is not limited to the above embodiment.

[Effect of idea]

As we have seen above, the photoelectric switch of this invention has the above structure, so it has the following effects.
It is highly practical as it can perform (1) to (4) all at once.

(1) The workability of sensitivity adjustment is improved. This is because the rotation speed of the rotation shaft of the sensitivity adjustment volume can be known from the display means. When multiple units are used, it becomes easy to set the same sensitivity for each unit.

(2) The rotation speed display means of the rotation axis of the sensitivity adjustment volume is compact and does not require a large installation space. This is because the fixed teeth, movable teeth, and eccentric cam are fitted in this order onto the rotating shaft of the sensitivity adjustment volume, and are located at almost the same position. This is because it can be accommodated in

(3) The positional accuracy of the sign of the rotation speed display means can be easily improved. This is because the positional accuracy of the marker essentially depends only on the tooth profile accuracy of the fixed teeth and movable teeth, and it is difficult to increase the positional accuracy of the marker by processing only the tooth profile accuracy with high precision. This is because it is not. Since the eccentric movement of the eccentric cam has no effect on the rotational position accuracy of the movable teeth, it is not related to the position accuracy of the marker.

(4) Easily responds to changes in the number of rotations of the sensitivity adjustment volume and changes in the amount of movement of the sign per rotation. This is because, in the case of this invention, the amount of movement of the mark per revolution can be easily changed by adjusting both or one of the fixed teeth and the movable teeth.

[Brief explanation of the drawing]

Fig. 1 is an exploded perspective view showing one embodiment of the photoelectric switch according to this invention, Fig. 2 is a plan view of the same, and Fig. 3 is a fixed tooth, a movable tooth, and an eccentric cam connected to the rotating shaft of the sensitivity adjustment volume. 4a and b are respectively a plan view and a sectional view showing the fixed teeth, and FIGS. 5a,
b and c are a plan view, a cross-sectional view, and a bottom view showing the eccentric cam, respectively; Fig. 6 a and b are a cross-sectional view and a bottom view showing the movable teeth, respectively; and Fig. 7 is the rotation of the rotation axis of the sensitivity adjustment volume. It is an explanatory view explaining the relationship with the position of a sign. 1... Sensitivity adjustment volume, 1a... Rotation axis, 2
... Display means, 10 ... Fixed teeth, 10c ... External teeth, 11 ... Movable teeth, 11b ... Internal teeth, 12 ...
Eccentric cam, 12c... cam part, 13... connecting rod,
14...scale, 16...marker.

Claims (1)

[Scope of utility model registration request] A photoelectric switch is equipped with a sensitivity adjustment volume, the sensitivity is adjusted by rotating a rotating shaft provided on the volume, and the upper limit of the rotation is one rotation or more, and the rotating shaft has fixed teeth, movable teeth, and an eccentric cam. They are fitted in this order, and the eccentric cam and rotating shaft are connected by a connecting rod so that they work together.
The fixed teeth are stopped from rotating and external teeth are formed on the side facing the movable teeth, and the lower part of the eccentric cam is a cam part that rotates eccentrically from the axis of the rotating shaft, A hole is formed in which the cam part of the eccentric cam fits, and internal teeth that engage with the external teeth of the fixed teeth are formed on the side facing the fixed teeth with a larger number of teeth than the external teeth. ,and,
A mark is attached to the outer periphery, and the position of the mark is shifted in accordance with the rotation of the rotation axis, and the part surrounding the movable tooth is
1. A photoelectric switch characterized in that a scale is provided to indicate the number of revolutions within the range of movement of the mark, and the scale and the mark serve as display means for displaying the number of revolutions of the rotating shaft.