JPH0566938U - Bobbin for transformer - Google Patents

Abstract

(57) [Summary] (Modified) [Purpose] To provide a transformer bobbin in which the lead wire 3a of the inner winding 3 does not approach the high-voltage outer winding 5 to cause dielectric breakdown. [Constitution] In a transformer bobbin including a base portion (10) in which terminals (2) are implanted and a winding shaft, another bobbin near the tip of a slit (12) provided on the side surface of the base portion (10) for pulling out a lead wire of an inner winding is provided. A wide portion 12a that is wider than the portion is formed. [Effect] When the winding is applied, the lead wire 3a of the inner winding 3
Engages with the stepped portion 12b in the wide portion 12a and is held so as not to approach the outer winding 5 too much, so that a sufficient creeping surface is provided between the lead wire 3a of the inner winding 3 and the outer winding 5. The distance can be secured.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a structure of a transformer bobbin suitable for a high frequency boosting transformer having a high voltage outer winding.

[0002]

[Prior Art]

 FIG. 1 is a front sectional view showing a configuration example of a bobbin 1 in a conventional step-up transformer, showing a wound state. The bobbin 1 is provided with a base portion 10 in which terminals 2 are planted on two opposite side surfaces, and a winding shaft 20 projecting upward from the center of the base portion 10, and a collar 22 is provided at the upper end of the winding shaft 20. It is provided. Slits 12 reaching the vicinity of the winding shaft 20 and slits 13 shallower than the slits 12 are provided on the two side surfaces of the base portion 10 on which the terminals 2 are implanted. As shown in FIG. 2, a large number of lead wires 3a of the inner winding 3 on the low voltage side wound around the winding shaft 20 are drawn out through one slit 12 and are respectively connected to predetermined terminals 2.

An outer winding 5 having a high voltage is wound on the outer side of the inner winding 3 via an insulating ring 4, and its lead wire 5 a is drawn out through the other slit 13 and connected to the terminal 2, respectively. Has been done. The inner winding 3 has a large number of lead wires due to taps provided and the feedback winding wound together, and since the total number of turns is small, many lead wires are wound with slits 12. It will be concentrated and derived from the tip close to the axis 20. A protrusion 14 is provided on the lower surface of the base 10 near the root of the terminal 2.

[0004]

[Problems to be solved by the device]

 When the lead wire 3a of the inner winding 3 is connected to the terminal 2, the lead wire 3a may slide in the slit 12 and be pulled out to the outer winding 5 side. Since the outer winding 5 is exposed in the slit 12 in the immediate vicinity of the inner winding 3, the biased low voltage lead wire passes near the high voltage outer winding 5. As a result, the lead wire of the inner winding 3 having a large potential difference and the outer winding 5 may be discharged to cause a dielectric breakdown.

[0005]

[The purpose of the device]

 An object of the present invention is to provide a bobbin for a transformer in which the lead wire 3a of the inner winding 3 does not approach the high-voltage outer winding 5 to cause insulation breakdown.

[0006]

[Means for Solving the Problems]

 The present invention is characterized in that a wide portion having a wider width than other portions is formed in a deep portion of a slit provided in a bobbin for pulling out a lead wire.

[0007]

【Example】

 An embodiment of the transformer bobbin according to the present invention is shown in FIG. In the following figures, the same parts as those of the prior art are designated by the same reference numerals as those in FIGS. 1 and 2. The bobbin shown in FIG. 3 is different from the conventional one in the shape of the slit 12 for pulling out the lead wire 3a of the inner winding. That is, in the bobbin of the present invention, a wide portion 12a having a wider width than other portions is formed near the tip of the slit 12. FIG. 4 shows a state in which the bobbin is wound. All the lead wires 3a of the inner winding 3 are drawn out through the wide portion 12a. Even if these lead wires 3a are strongly pulled when they are led out in the direction of the respective terminals 2, they have a step 12b (FIG. 3) at the edge of the wide part 12a, so that they are engaged with this step 12b. , It does not enter the narrow part of the slit 12.

[0008]

[Effect of the device]

 When the bobbin of the present invention is wound, the lead wire 3a is engaged with the step portion 12b of the wide portion 12a of the slit and is held so as not to come too close to the outer winding 5. A sufficient creepage distance is secured between the lead wire 3a of No. 3 and the outer winding 5, and there is an effect that the occurrence of insulation breakdown can be prevented.

[Brief description of drawings]

FIG. 1 is a front sectional view showing a conventional example of a trans bobbin having a winding.

FIG. 2 is a bottom view of a part of the trans bobbin.

FIG. 3 is a partial bottom view showing an embodiment of the bobbin of the present invention.

FIG. 4 is a partial bottom view of the bobbin of the present invention with windings.

[Explanation of symbols]

 10 Base part 12 Slit 12a Wide part 20 Winding shaft

Claims (1)

[Scope of utility model registration request] 1. A bobbin for a transformer, comprising a base portion having terminals implanted therein and a winding shaft, wherein a slit for drawing out a lead wire of an inner winding is formed on a side surface of the base portion.
A bobbin for a transformer, wherein a wide portion is provided near the tip of the slit.