JPH058933U - Tube type trimmer capacitor - Google Patents

Abstract

(57) [Summary] [Purpose] The minimum capacitance is small,
(EN) Provided is a variable-capacity tube-type trimmer capacitor whose capacitance does not change and whose capacitance is stable even when the temperature changes. [Structure] Square tubular body 1 formed of dielectric ceramic
1, electrodes 12 and 13 are formed at intervals above and below 1, and a terminal block 17 having a screw hole 20 is fixed to the lower end of the rectangular tubular body 11, and the lower end is angled inside the rectangular tubular body 11. A conductive moving element 24, which is elastically pressed against the inner surface of the tubular body 11, is movably accommodated, and the upper end portion of the moving element 17 fits in the screw hole 20 of the terminal block 17.
Since the screw 22 connected to is screwed, the position of the mover 24 does not change even when vibration is applied, and the capacitance is stable.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

  The present invention relates to a variable-capacity tube-type trimmer capacitor used in communication equipment. To do.

[0002]

[Prior art]

  As shown in FIG. 11, a conventional tube type trimmer capacitor has a dielectric ceramic Electrodes 2 and 3 are formed on the outer periphery of a cylinder 1 made of black A terminal block 5 having a screw hole 4 is attached to the lower end of the cylinder 1. screw A screw 6 is screwed into the hole 4, and by turning the screw 6, the upper end of the screw 6 While moving the conductive rotor 7 as a moving element fixed to the ing. The lead lines 8 and 9 are drawn out from the electrodes 2 and 3.   This tube type trimmer condenser rotates the screw 6 to move the rotor 7 up and down. By moving, the positional relationship between the electrodes 2 and 3 and the rotor 7 is changed, and between the lead wires 8 and 9 The capacitance is changing.

[0003]

[Problems to be solved by the device]

  In the above configuration, the rotor 7 moves up and down while rotating, There is a case where the rotor 7 comes into contact with the cylinder 1 and the inner peripheral portion is worn. Therefore, the usage period is long Over a period of time, the inner circumference of the cylinder 1 wears and a gap is created between it and the rotor 7, Air is present in the gap. This air is different from the dielectric ceramic forming the cylinder 1. Since the dielectric constants are different, even if the upper and lower positions of the rotor 7 are the same, there is no gap. There is a problem that the capacitance is reduced as compared to when it is not. In addition, the air temperature in the gap There is also a problem that the capacitance becomes unstable when the degree changes.   In the conventional tube type trimmer capacitor, the electrodes 2 and 3 are provided on the outer circumference of the cylinder 1. However, the capacitance cannot be increased in a limited space.

[0004]   The present invention has been made in view of the above circumstances, and its purpose is to reduce the minimum capacitance. Even if used for a long time, the capacitance corresponding to the position of the mover does not change, and Variable-capacity tube-type trimaco that has stable capacitance even when the temperature changes To provide a capacitor.   Another purpose is to obtain a large capacitance in a limited space. To provide a tube-type trimmer capacitor.

[0005]

[Means for Solving the Problems]

  The tubular trimmer capacitor of claim 1 is formed from a dielectric ceramic. The electrodes are formed at intervals above and below the outer periphery of the rectangular tubular body,   Fix the terminal block with screw holes at the lower end of this rectangular tubular body,   A conductive member whose lower end is elastically pressed against the inner surface of the rectangular tubular body inside the rectangular tubular body. The mover is movably accommodated,   The screw whose upper end is connected to the mover is screwed into the screw hole of the terminal block. It has special characteristics.   3. The tube-shaped trimmer capacitor according to claim 2, wherein the rectangular tubular body has a pair of opposing surfaces. It is characterized in that an electrode is formed on the outer peripheral portion of the portion.

[0006]   The tube type trimmer capacitor according to claim 3 is formed of a dielectric ceramic. The electrodes are formed at intervals above and below the outer periphery of the tubular body,   Fix the terminal block with screw holes at the lower end of this tubular body,   Conductive movement in which the lower end elastically presses against the inner surface of the tubular body inside the tubular body Accommodates the child in a movable manner,   Screwing a screw whose upper end is connected to the mover into the screw hole of the terminal block,   A holding portion that elastically presses the screw is integrally provided on the upper end portion of the terminal block. It has special characteristics.   The holding portion of the tubular trimmer capacitor according to claim 4, wherein the holding portion is formed along the axial direction. It is characterized in that it has a plurality of formed groove portions.

[0007]

[Action]   According to the tube type trimmer capacitor of claim 1, the screw connected to the mover is When turned, the mover moves up and down in the rectangular tubular body, and the relative position between the upper and lower electrodes and mover moves. It changes and the capacitance becomes variable.   Since the electrodes are formed on the outer peripheral part of the rectangular tubular body made of dielectric ceramic, The area of the electrode is larger than in the case of the shape electrode.   Furthermore, since the lower end of the mover elastically presses the inner surface of the rectangular tubular body, Does not change, and the position of the mover does not change even when vibration is applied.   According to the tube type trimmer capacitor of claim 2, the area of the electrode is the electrode of claim 1. It is about 1/2 of that of poles, so it is easy to manufacture capacitors with extremely small capacitance. In addition, standard parts can be used for capacitors with small constant capacitance. .

[0008]   According to the tube type trimmer capacitor of claim 3, the screw connected to the mover is When turned, the mover moves up and down in the tubular body, changing the positional relationship between the upper and lower electrodes. And the capacitance becomes variable.   Also, the lower end of the moving element elastically presses against the inner surface of the tubular body, and Since the ridge is pressed, the position of the mover does not change even when vibration is applied.   According to the tube type trimmer capacitor of claim 4, the holding portion can be easily processed. .

[0009]

【Example】

  Hereinafter, a first embodiment of the present invention will be described with reference to FIGS.   The outer cylinder 11 as a rectangular cylinder is formed of a dielectric ceramic into a rectangular cylinder and has an upper end. The upper electrode 12 is formed on the entire outer periphery of the lower part, and is spaced apart from the upper electrode 12, and the entire outer periphery of the lower end is formed. A lower electrode 13 having a width smaller than that of the upper electrode 12 is formed on the surface. These electrodes Nos. 12 and 13 are electroless platings made of silver, nickel, copper or alloys thereof. Alternatively, it is formed by applying a conductive paint containing these metals.

[0010]   The cap 14 is drawn from a conductive metal such as a copper alloy into a square tube with a cover, It is attached to the upper end of the outer cylinder 11 with an insulating sash 15 made of Teflon interposed. The cap 14 is in contact with the upper electrode 12 on the inner surface and is exposed from the outer surface. The lead line 16 is drawn out.

[0011]   The terminal block 17 has a mounting portion 18 formed on the lower portion of the collar portion 17a and a cylindrical holding portion on the upper portion. The portion 19 is formed, and the screw hole 20 is formed inside the holding portion 19. . A screw 18a is formed on the outer peripheral portion of the mounting portion 18, and a part of the mounting portion 18 is cut out to prevent the rotation. 18b. Further, the holding portion 19 has a plurality of groove portions 21 along the axial direction. Is formed, which reduces the diameter of the screw hole 20 and allows the screw 22 to be screwed into the inside. It is pressed and held elastically. The terminal block 17 is provided on the upper surface of the collar portion 17a with the outer cylinder 11 The lower end is brought into contact, and the flange 17a and the lower electrode 13 are soldered and fixed to the outer cylinder 11. Has been. The lead wire 23 is drawn out from the lower electrode 13.

[0012]   The mover 24 is drawn from a conductive material and is drawn downward from the rectangular upper surface 24a. The side surface portion 24b is formed in a slope shape that gradually expands toward the side. This side surface 24b A groove portion 24c is formed in the groove 24c, and the lower end portion 24d has elasticity.   The mover 24 is housed inside the outer cylinder 11, and the upper surface portion 24 a holds the washer 25. Is caulked to the upper end of the screw 22 and is rotatably connected to the screw 22. The lower end 24d is pressed against the inner surface of the outer cylinder 11.

[0013]   Next, the operation of the above configuration will be described.   In FIG. 2 in which the mover 24 is located at the lowermost end, the mover 24 is connected to the lower electrode 13 and Since they face each other and a large distance exists between the upper electrode 12, the capacitance is It is the smallest.

[0014]   When the screw 22 is rotated clockwise from this state, the screw 22 rises. The mover 24 Although it does not rotate with respect to the outer cylinder 11, the lower end 24d is pushed up by the screw 22 and It rises while contacting the inner surface of the outer cylinder 11. As a result, the mover 24 moves the lower electrode 13 2 and the upper electrode 12, the capacitance increases more than in the state shown in FIG. Then, when the mover 24 moves to the upper end as shown in FIG. 3, the mover 24 moves upward. The capacitance is maximized when facing the partial electrode 12. Thus, the mover 24 has the lower end portion 2 4d is elastically pressed against the inner surface of the outer cylinder 11, and the screw 22 is elastically pressed against the holding portion 19. Since they are in contact with each other, even when vibration is applied, the inner surface of the outer cylinder 11 and the moving element 24 side The position relative to the surface 24b does not change.

[0015]   According to the above-mentioned example, the following effects are produced. That is, (1) Since the electrodes 12 and 13 are formed on the outer peripheral portion of the outer cylinder 11 having a rectangular cylindrical shape, The areas of the electrodes 12 and 13 can be made larger than those of the electrodes 2 and 3 in the shape of a circle. If electrode 12 , 13 are set to be the same as the electrodes 2 and 3, the length of the outer cylinder 11 is shortened. Therefore, the miniaturization of the whole can be achieved.

[0016] (2) The lower end 24d of the mover 24 is always elastically pressed against the inner surface of the outer cylinder 11. Therefore, the relationship between the mover 24 and the upper electrodes 12 and 13 is always constant, and As shown in the figure, a gap is formed between the two and the capacitance changes, or the capacitance changes in response to changes in temperature. Capacity does not become unstable. (3) Further, the moving element 24 may be moved carelessly even when vibration or the like is applied. Absent.

[0017] (4) Since the holding portion 19 elastically holds the screw 22, the screw 22 is careless. It is never turned. Moreover, when changing the capacitance, turn the screw 22. For example, since the screw 22 moves the mover 24 while expanding the inner diameter of the holding portion 19, The capacitance can be changed easily.

[0018]   FIG. 5 shows a second embodiment of the present invention, which differs from the first embodiment in that The electrodes 26 and 27 are formed only on the outer peripheral portions of the pair of surface portions. The other one Insulating paint is applied to the outer periphery of the pair of surface portions.   According to the second embodiment, in addition to the effect of the first embodiment, the electrodes 12 and 13 have Since the electrode area can be reduced to about 1/2, the standard parts of the first embodiment are used. Can be applied to capacitors with small capacitance.

[0019]   6 to 8 show a third embodiment of the present invention.   The outer cylinder 31 is formed of a dielectric ceramic into a cylindrical shape, and is provided on the entire outer circumference of the upper end portion. The partial electrode 32 is formed, and the lower electrode 33 is formed on the entire outer periphery of the lower end portion with a space therebetween. Has been formed. These electrodes 32 and 33 are all made of silver, nickel, copper or this. Electroless plating with these alloys or application of conductive paint containing these metals Is formed. The lead wire 34 is drawn from the upper electrode 32. It

[0020]   The terminal block 35 has a mounting portion 36 formed at the lower portion of the collar portion 35a and a cylindrical holding portion at the upper portion. The portion 37 is formed and the screw hole 38 is formed inside the holding portion 37. . Further, the holding portion 37 is formed with two groove portions 39 in the circumferential direction. to this As a result, the holding portion 37 is shortened from the position shown by the dotted line in FIG. 8 to the position shown by the solid line. Thus, the pitch of the screw holes 38 in that portion becomes small, and the screw 22 that is screwed inside is It keeps pressure contact. This terminal block 35 is provided on the upper surface of the collar portion 35a, under the outer cylinder 31. The end portions are brought into contact with each other, and the collar portion 35a and the lower electrode 33 are soldered and fixed to the outer cylinder 31. ing. Then, the lead wire 40 is drawn out from the upper electrode 32, and A lead wire 41 is drawn out.

[0021]   The mover 42 is drawn from a conductive material, and is moved downward from the disk-shaped upper surface portion 42a. The side surface portion 42b is formed in a slope shape that gradually expands toward the. This side surface portion 42b A groove portion 42c is formed in the groove, and the lower end portion 42d has elasticity.   The mover 42 is housed inside the outer cylinder 31, and the upper surface portion 42 a is located above the screw 22. It is caulked to the end and is rotatably connected to the screw 22 so that the lower end 42d is It is pressed against the inner surface of the outer cylinder 31.

[0022]   9 and 10 show a fourth embodiment of the present invention, which is in phase with the third embodiment. The difference is that the holding portion 43 is composed of a plurality of groove portions 44 formed along the axial direction. Where it is.   Also in these third and fourth embodiments, the same effect as that of the first embodiment is obtained. It is a thing.

[0023]   The invention is not limited to the embodiment described above and shown in the drawings, for example For example, the lower electrode is formed only on the outer peripheral portion of the pair of facing surface portions, and the upper electrode is formed on the outer peripheral portion. If formed over the entire area, the minimum capacitance can be small and the maximum capacitance can be large. For example, various modifications are possible without departing from the scope of the invention.

[0024]

[Effect of device]

  As is apparent from the above description, the present invention has the following effects. That is,   According to the tube type trimmer capacitor of claim 1, it is formed from a dielectric ceramic. Since the electrodes are formed on the outer circumference of the rectangular prism, the overall size can be reduced and vibration can be reduced. The capacitance does not change even when the temperature is changed, and the capacitance changes even when the temperature changes. The capacitance is stable even if it is not used and is used for a long time.   According to the tube type trimmer capacitor of claim 2, a capacitor having a small minimum capacitance. It can be applied to the Densa by using standard parts.

[0025]   According to the tube type trimmer capacitor of claim 3, even when vibration is applied, the transfer is prevented. The pendulum does not move, the capacitance does not change even when the temperature changes, and it is used for a long time However, the capacitance is stable.   According to the tube type trimmer capacitor of claim 4, the holding portion can be easily processed. .

[Brief description of drawings]

FIG. 1 is an exploded perspective view of a first embodiment of the present invention.

FIG. 2 is a vertical sectional front view.

FIG. 3 is a vertical sectional front view in different states.

FIG. 4 is an external perspective view.

FIG. 5 is an exploded perspective view of a second embodiment of the present invention.

FIG. 6 is an exploded perspective view of a third embodiment of the present invention.

FIG. 7 is a side view of the terminal block.

FIG. 8 is a vertical sectional front view.

FIG. 9 is an exploded perspective view of a third embodiment of the present invention.

FIG. 10 is a vertical sectional front view.

FIG. 11 is a vertical sectional front view of a conventional example.

[Explanation of symbols]

11 Outer cylinder (square tubular body) 12 Upper electrode 13 Lower electrode 17 terminal block 19 Holding part 20 screw holes 21 groove 22 screws 24 mover 24d lower end 26 Upper electrode 27 Lower electrode 31 Outer cylinder (cylindrical body) 32 upper electrode 33 Lower electrode 35 terminal block 37 holding part 38 screw holes 39 Groove 42 Mover 42d lower end 43 holding part

Claims (4)

[Scope of utility model registration request] 1. A rectangular tubular body formed of a dielectric ceramic and having electrodes formed at intervals above and below the outer periphery, and a terminal block fixed to the lower end of the rectangular tubular body and having a screw hole. A conductive mover that is movably housed inside the rectangular tubular body and has a lower end portion elastically pressed against an inner surface of the rectangular tubular body; and an upper end portion screwed into a screw hole of the terminal block. A tubular trimmer capacitor comprising a screw connected to the mover. 2. The tube-type trimmer capacitor according to claim 1, wherein the rectangular tubular body has electrodes formed only on the outer peripheral portions of a pair of opposing surface portions. 3. A cylindrical body made of a dielectric ceramic, in which electrodes are formed at intervals above and below the outer periphery, and a terminal block fixed to the lower end of the cylindrical body and having a screw hole, A conductive moving member that is movably accommodated inside the cylindrical body and has a lower end portion elastically pressed against the inner surface of the cylindrical body; A tube-type trimmer capacitor comprising: a screw connected to the terminal block; and a holding part integrally formed at an upper end of the terminal block to elastically press the screw. 4. The tube type trimmer capacitor according to claim 3, wherein the holding portion has a plurality of groove portions formed along the axial direction.