JPS58199518A - Variable porcelain condenser - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a variable ceramic capacitor used in various electrical devices, etc. In general, a variable ceramic capacitor is made of The rotor part 3 has a semicircular rotor electrode 2 formed thereon, and the stator substrate 4, which is made of anopena, steatite, etc., is coated with silver paste, etc. on the top, side, and bottom surfaces, as shown in FIG. 2B- and -Q. The stator portion 14 includes electrodes 6 to 13 made of metallized layers. 6 is a stator electrode, and 6 is a dummy electrode that is flush with the upper surface of the stator electrode 6.

The electrode element connected to the stator electrode 6 is connected to a lower electrode 9 via a side electrode 8. Further, the electrode 10 is connected to lower electrodes 12 and 13 via side electrodes 11.

A rotor shaft 16 having a head 16 passes through the center of the rotor portion 3 and the stator portion 14 via an insulating wire and a pager 17. Further, a leaf spring 18 is coupled to the lower end of the rotor shaft 16, and the rotor portion 3 and the stator portion 14 are pressed into contact with each other by the leaf spring 18.

Further, the head 15 of the rotor shaft 16 is connected to the rotor electrode 2 of the ceramic dielectric 1 of the rotor portion 3 by solder 19.

Conventionally, in this type of variable ceramic capacitor, the side electrodes 8, 11 and the bottom electrodes 9, 12 were manually soldered to the conductive parts of the printed circuit board, but recently,
There is a growing demand for automatic mounting components that can be inserted into a printed circuit board using an automatic insertion machine and soldered using a reflow method, etc., and the variable magnetic capacitor shown in Figure 1 has the following problems. was there.

That is, since the leaf spring 18 and the lower end constricting portion of the rotor shaft 16 are arranged on the lower surface of the stator board 4, when mounting the printed circuit board, it is necessary to make a hole in the printed circuit board so that the leaf spring 18 does not hit. 0 In printed circuit boards for automatic mounting, the size of the board is generally small and chip components are mounted on the front and back sides.Drilling holes in the printed circuit board reduces the mounting area, which makes soldering difficult. There were problems such as the strength was weakened, the mounting position was limited and flexibility was lost, and the conductive pattern on the printed circuit board had to be routed around.

Furthermore, since the side electrodes 11 and the bottom electrodes 12 of the stator board 4 are electrically connected to the leaf spring 18 via the bottom electrodes 13, when the bottom electrodes 12 of the stator board 4 are soldered to the printed circuit board, , the solder is the bottom electrode 13
There was a risk of the deterioration of the properties of the leaf spring 18 due to the change in the characteristics of the leaf spring 18 and the change in rotational torque.The present invention solves these conventional drawbacks. ,
An embodiment of the present invention will be explained below using the drawings of FIGS. 3 to 5.

In the figure, 2o is a rotor, and this rotor 2o is
It is constructed by forming semicircular rotor electrodes 22 on the upper surface of a rotor substrate 21 made of a disk-shaped porcelain dielectric five-page body having a through hole in the center.

23 is a stator, and this stator 23 is shown in FIG.
As shown in FIG. 3-d, electrodes made of a metallized layer of silver or the like are formed on the top, side and bottom surfaces of a stator substrate 24 made of square alumina, steatite, etc. that is larger than the diameter of the rotor 2o. It's being done. A through hole 25 is provided in the center of the stator board 24, and a recess 25 is provided in the lower surface of the stator board 24, communicating with the through hole 25 and having a larger diameter than the through hole 25.
6 is provided. Further, the recess 26 on the lower surface of the stator board 24 communicates with a notch 27 provided on the side surface.

In addition, in FIGS. 5a to 5d, 28 is the stator board 24.
This is a semicircular stator electrode formed on the upper surface, and by changing the opposing area between this stator electrode 28 and the rotor electrode 22 of the rotor 20, the capacitance value obtained by the ceramic dielectric can be changed. can be done. Further, the stator electrode 28 is connected to a lower surface electrode 29 as an external connection portion formed on the lower surface of the stator substrate 28 via a side electrode 30 formed on the side surface of the stator substrate 28.

31 is a dummy electrode formed on the upper surface of the stator substrate 24 so that its upper surface is flush with the upper surface of the stator electrode 28. By forming the dummy electrode 31, the rotor 2
0 can be placed on the stator 23 and rotated smoothly without rattling.

32 is the stator electrode 28 on the stator substrate 24;
This upper surface electrode 32 is formed at the end of the side opposite to the side, and this upper surface electrode 32 is formed in the notch 27 of the stator substrate 24.
It is connected to lower surface electrodes 33 and 34 as the other external connection portion formed on the lower surface of the stator substrate 24 via a side electrode 35 formed on the side surface of the stator substrate 24.

That is, two external connection parts are formed on the lower seven surfaces of the opposing ends of the stator board 24.

In addition, in the stator 23, a solder flux is applied or a solder layer is applied to the side electrodes 30.35 and the bottom electrodes 29, 33.34 to prevent oxidation of the metallized surface and to facilitate soldering to the conductive parts of the printed circuit board. is formed.

Further, in FIGS. 3 and 4, 36 is a rotor shaft, and this rotor shaft 36 has a circular head that is approximately the same size as the rotor base plate 21 and has a notch 37 in a part of its outer circumference. The rotor shaft 36 has a section 38, and the rotor shaft 36 has a
By connecting the head 38 and the rotor electrode 22 of the rotor 2o at the notch 37 with solder 40 with a disc-shaped insulating washer 39 interposed between the head 38 and the rotor 20, the rotor 20 It is integrated with. That is, by rotating the rotor shaft 36, the rotor 2
o also rotates together with the rotor shaft 36.

41 is a leaf spring having a terminal piece 42;
1 is fitted into the tip of the rotor shaft 36 that protrudes into the recess 26 of the stator substrate 24 by passing through the through hole of the rotor 2o and the through hole 26 of the stator substrate 24 of the stator 23, and By comparison, it can be seen that it is fixed within the recess 26 of the stator board 24.

The rotor shaft 36 is rotatably supported by the leaf spring 41 with the rotor 2° in elastic contact with the upper surface of the stator 23. Further, the terminal piece 42 of the leaf spring 41 is inserted into the recessed part of the stator board 24 so that the tip reaches the upper surface of the stator board 24 from the cutout part 27 of the stator board 24.
The tip of this terminal piece 42 is connected to the upper electrode 32 of the stator board 24 by a conductive base 43. Note that the terminal piece 42 and the upper electrode 32 of the stator board 24 may be connected by soldering.

That is, in the variable magnetic capacitor of the present invention, the rotor 20+7) rotor electrode 22 is connected to the upper surface electrode 32 of the stator board 24 and the lower surface electrode 33, 34 as an external connection part via the rotor shaft 36 and the leaf spring 41. Therefore, a predetermined capacitance can be obtained between the lower surface electrode 29 and the lower surface electrodes 33, 34.

In addition, in the above embodiment, the terminal piece 42 of the leaf spring 41
is connected to the upper surface electrode 32 formed on the upper surface of the stator substrate 24, but a side electrode 36 connected to the upper surface electrode 32 is also formed in the notch 27 of the stator substrate 24, and the leaf spring is connected in the notch 27. The 41 terminal pieces 42 may be connected by soldering.

As described above, according to the variable magnetic capacitor of the present invention, a recess is provided on the lower surface of the stator board, and a leaf spring that brings the rotor into elastic contact with the stator is disposed within the recess. Since it does not protrude, there is no need to provide holes or other relief parts on the printed circuit board in which the variable magnetic capacitor is installed, and this makes it easier to solder the lower electrodes of the stator board and the conductive parts of the printed circuit board.
In addition, a terminal piece is provided on the leaf spring, and the terminal piece is pulled out through the recess and connected to the top electrode or side electrode of the stator board, so the bottom electrode of the stator board is soldered to the conductive 10 base part of the printed circuit board. In this case, the solder does not adhere to the leaf spring, the characteristics of the leaf spring do not change, and the rotational torque does not change. Since they are connected, it is also possible to prevent poor contact from occurring in the electrical lead-out of the rotor electrodes.

Furthermore, in the variable ceramic capacitor of the present invention, since the lower surface of the stator board is flush with no protrusions, it can be made into a face bonding type variable ceramic capacitor, and can be easily incorporated into a printed circuit board. .

[Brief explanation of drawings]

Figure 1 is a cross-sectional view of a conventional variable magnetic capacitor, Figure 2 a
is a top view of the stator portion of the same capacitor, FIG. 2 is a sectional view taken along line A-A' in FIG. 2a, FIG. A top view of a variable ceramic capacitor according to an embodiment, FIG. 3 and FIG. 3a.
Figure 4 d is a bottom view of the same capacitor, the figure on page 411 is a sectional view taken along line C-C' of Figure 4 a, and Figure 6 a is a cross-sectional view taken along line C-C' of Figure 4 a. Figure 6 is a top view of the stator portion of the same capacitor, Figure 6 is a sectional view taken along the line DD' in Figure 6a, Figure 5C is a bottom view of the stator part, and Figure 6d is the figure 5. C's E -E
It is a sectional view taken along the line '. 2o... Rotor, 21... Rotor board, 22... Rotor electrode, 23... Stator, 24... Stator board, 26...・・・・・・
・Recessed portion, 27...Notch, 28...Stator electrode, 29, 33, 34...Bottom electrode, 30.35...Side electrode, 32・・・・・・
・Top electrode, 36...Rotor shaft, 38...
... Head, 4o... Solder, 41... Leaf spring, 42... Terminal piece, 43... Conductive paste. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 2 Figure 3 Figure 4 (α) 33 c34 35 (b) 36 ga 34/21 242 4.3°4 no 36 3ri Figure 5 3ρ

Claims (1)

[Scope of Claims] A stator substrate having a semicircular stator electrode formed on its upper surface and a recess formed on its lower surface, and a semicircular rotor electrode disposed on the stator substrate and facing the stator electrode on its upper surface. It has a rotor board made of a disc-shaped ceramic dielectric material having a shape formed thereon, and a head part connected to the rotor electrode of the rotor board, and the tip part penetrates through the rotor board and the stator board to form a bottom surface of the stator board. The rotor shaft is provided with a rotor shaft projecting into the recess, and a leaf spring rotatably supporting the rotor shaft with the rotor substrate in elastic contact with the stator substrate and disposed within the recess of the stator substrate, A terminal piece is provided on the leaf spring, and the terminal piece passes through the recess of the stator board and has a tip located on the upper surface, and an electrode for external connection is connected to each of the stator electrode and the terminal piece from the side surface to the bottom surface of the stator board. 2 pages variable ceramic capacitor 0 characterized by forming