JPS6322006B2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a time switch.

Conventionally, as shown in FIG. 1, a groove 2 is provided around the entire circumference of a dial 1 which is rotated at a constant speed in the direction of an arrow by a motor or the like. A time switch is provided in which the set cam 5 is rotated in fixed pitch increments to open and close the contacts. 6 is a display board that displays ON and OFF, and 7 is a display board that displays ON and OFF.
OFF switch cam that operates OFF contact piece 9, 8
is an ON switch cam that operates the ON contact piece 10,
11 is a central partition plate provided between the OFF switch cam 7 and the ON switch cam 8; the set cam 5, the set section 6, the OFF switch cam 7,
The ON switch cam 8 and the central partition plate 11 are integrally connected by a shaft 12. Reference numeral 13 denotes a contact block, which has grooves 14 and 15 for fixing the OFF contact piece 9 and the ON contact piece 10, and has a mounting hole 16.
It is fixed to the frame 17 by.

Figures 2a to 4b show the time switch
Indicates the ON operation order. First, when the setter 3 and the set cam 5 begin to engage as shown in FIG. 2a, the contacts of the contact pieces 9 and 10 remain open as shown in FIG. 2b. When the dial 1 gradually rotates and reaches the position shown in Fig. 3a, the ON contact piece 10
The tip of the switch falls from the ON switch cam 8 and the contact closes (see Figure 3b). Furthermore, just before the dial 1 rotates and the engagement between the setter 3 and the set cam 5 is released (see Fig. 4a), the OFF switch cam 7 also rotates further than when the ON contact piece 10 falls, and the contact pressure decreases. (see Figure 4b).
Then, at the moment when the engagement between the set element 3 and the set cam 5 is released, the OFF contact piece 9 is moved to the OFF switch cam 7.
However, at this time, the OFF contact piece 9 presses the next tooth part of the OFF switch cam 7, and the switch cam 7 moves in the direction shown by the arrow in Fig. 4b.
The force that tries to rotate works, and the set cam 5
The tip of the ON contact piece 10 momentarily rotates in the opposite direction to the position where it contacts the base of the rear wall surface 8a of the ON switch cam 8. Along with this reverse rotation, the display board 6 will also move back a little, but in anticipation of the return angle, the pointer 6 will be moved back as shown in Figure 6.
8 is provided on the frame 17 or the like so that the pointer 18 corresponds accurately to the center of the ON/OFF display section of the display board 6.

However, when performing the OFF operation contrary to the above, the moment the setter 3 separates from the set cam 5, the ON contact piece 10 detaches from the ON switch cam 8 and falls, for the same reason as in the above case. OFF
The set cam 5 rotates in the opposite direction until the contact piece 9 comes into contact with the base of the rear wall of the OFF switch cam 7. Normally, contact piece 9 for OFF and contact piece 10 for ON
In order to ensure an insulating distance, the contact pieces 9 and 10 are arranged in parallel with an interval equal to the thickness of the contact points, and both contact pieces 9 and 10 are formed to have the same length. Since the fulcrum positions are different, the falling trajectory of the tip of the OFF contact piece 9 and the falling trajectory of the tip of the ON contact piece 10 are different as shown in FIG. 5, and the falling position to the switch cam differs by a distance a.
The reverse rotation angle differs by this distance a between ON and OFF, and as shown in FIG. 7, the pointer 18 and the ON and OFF display portions of the display board 6 no longer correspond accurately. In other words, display deviation occurs when ON and OFF,
It gives the illusion of malfunction or incomplete operation.

The present invention has been made to solve this problem, and it is an object of the present invention to provide a time switch in which the angle of reverse rotation of the set cam is made equal between ON and OFF, thereby eliminating display deviation.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the accompanying drawings, which are examples of the present invention.

Figures 8 and 9 show the ON and OFF switch cams and the ON and ON time switches according to the present invention.
An exploded view showing the relationship with the OFF contact piece is shown, 7.
8 is an OFF switch cam and an ON switch cam of the same shape with four teeth spaced at 90° intervals as before, and there is a partition plate 11 between the two switch cams.
These switch cams 7, 8 and partition plate 11 are provided coaxially with and rotate integrally with a set cam (not shown). The above ON switch cam 8 is at a constant angle θ= in the forward rotation direction (counterclockwise direction in the figure) with respect to the OFF switch cam 7.
See FIG. 8, which is located at a position relatively rotated by π/4+(B-α) (radians). Note that the angles α and β are as described below.

9 is a contact piece for OFF, 10 is a contact piece for ON, and these contact pieces 9 and 10 are almost contacts 9a and 10 as in the conventional case.
They are fixed to the contact base with an interval equal to the thickness of a. The tip of the ON contact piece 10 above is the OFF contact piece 9.
It protrudes by a predetermined length δ from the tip of the switch cam 7, 8, and the outer diameter of the switch cams 7 and 8 is d, and the surface of the tooth rear wall 8a at the moment when the tip of the ON contact piece 10 falls from the tooth of the ON switch cam 8. The angle between and the perpendicular line A passing through the cam center of switch cam 8 is α (radian),
If the angle between the surface of the rear wall 7a of the tooth section at the moment when the tip of the OFF contact piece 9 falls from the tooth section of the OFF switch cam 7 and the perpendicular line A passing through the cam center of the switch cam 7 is β (radian), then The length δ is given by δ=d/2(β−α). The angles α and β above are ON and OFF.
In order to equalize the reverse rotation angle of the set cam at different times, the distance b between the tip of the ON contact piece 10 and the rear wall 8a of the tooth part of the ON switch cam 8 when the ON contact piece 10 falls from the ON switch cam 8 is , OFF
The spacing b between the tip of the OFF contact piece 9 and the toothed rear wall 7a of the OFF switch cam 7 when the contact piece 9 falls from the OFF switch cam 7 is determined to be equal. In addition, at the moment when the set cam and the set element are separated, the contact pieces 9 and 10 are connected to the switch cam 7,
There is a slight delay compared to when falling from 8, but this delay angle is constant both when ON and when OFF, so if the above-mentioned interval b is kept equal, there will be no problem.

Therefore, the relative angle difference θ between the ON switch cam 8 and the OFF switch cam 7, and the ON contact piece 1
The relationship between the length difference δ between 0 and the OFF contact piece 9 is given by δ=d/2(θ−π/4).

Conventionally, the ON switch cam 8 and the OFF switch cam 7 are provided at positions that are relatively rotated by equal angles (for example, π/4 (radians)), and
Since the ON contact piece 10 and the OFF contact piece 9 were of the same length, the reverse rotation angle of the set cam was changed due to the difference in the falling trajectory of the tip of the ON contact piece 10 and the OFF contact piece 9.
There was a difference between ON and OFF. As described above, the present invention provides the ON switch cam 8 at a position relatively rotated by an angle θ (≠π/4) with respect to the OFF switch cam 7, and corresponds to the ON switch cam 8.
By making the lengths of the 0 and OFF contact pieces 9 different, the difference in the reverse rotation angle of the set cam due to the difference in the falling trajectory of both the contact pieces 9 and 10 is eliminated.

In the above embodiment, the number of tooth portions of the switch cams 7 and 8 is four, but it goes without saying that the number is not limited to this.

As described above, according to the present invention, the ON contact piece
By making it protrude from the OFF contact piece and placing the ON switch cam at a position rotated by a certain angle relative to the OFF switch cam, the ON contact piece and
At the moment when the OFF contact piece falls from the teeth of the ON switch cam and OFF switch cam, the angle of reverse rotation of the set cam is made equal to that at the ON time.
It is possible to eliminate display discrepancies between when it is OFF and when it is turned off.

[Brief explanation of the drawing]

Fig. 1 is an exploded perspective view showing the internal structure of a conventional time switch, Figs. 2 to 4 are explanatory diagrams of its operation, Fig. 5 is a partially enlarged view of Fig. 4b, and Figs. 6 and 7. is a plan view of the display part, and Figures 8 and 9 are for ON and OFF in the time switch according to the present invention.
FIG. 4 is an exploded plan view showing the relationship between the switch cam and the ON and OFF contact pieces. 1... Dial, 3... Set switch, 5... Set cam, 6... Display board, 7... Switch cam for OFF, 8... Switch cam for ON, 9... Contact piece for OFF, 10... Contact for ON. Piece 13...Contact stand.

Claims (1)

[Claims] 1 A setter is attached to the outer periphery of the dial, and this setter rotates the set cam in fixed pitch increments, and operates the ON and OFF contact pieces respectively. ON every pitch,
In a time switch that has a display board equipped with an OFF display and coaxial with and rotates integrally with the set cam, the tip of the ON contact protrudes from the tip of the OFF contact, and the ON switch cam is turned OFF. It is installed at a position relatively rotated by a certain angle in the forward rotation direction with respect to the switch cam for the above-mentioned ON.
When the contact piece for ON and the contact piece for OFF fall from one end face of the rear wall of the tooth part which is the fall surface of the ON switch cam and the OFF switch cam, the tip of both the contact pieces and the rear of the tooth part of both the switch cams fall. A time switch characterized by an equal distance from the wall base.