JPH054442U - Booster transformer - Google Patents

Abstract

(57) [Summary] [Objective] In a transformer used for boosting, for example, a liquid fuel ignition device, when the time constants of the primary coil and the secondary coil are reduced, the number of turns of the primary coil is reduced. In this case, it is an object to shorten the rise time of the secondary voltage without changing the output characteristic of the secondary coil, and at the same time obtain the optimum copper loss and coupling of the primary and secondary coils. [Structure] There is a core member 1 made of a magnetic material, a primary bobbin 2 is arranged coaxially with respect to its axis, and a plurality of primary coil units 31 and 32 are wound thereon so as to be connected in parallel. Further, a secondary bobbin 2 is coaxially arranged on these, and a secondary coil 5 having a number of turns corresponding to the number of turns of each of the primary coil units 31 and 32 is wound thereon.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a transformer for use in a liquid fuel ignition device for boosting, for example, igniting.

[0002]

[Prior Art]

 In a conventional boosting transformer, for example, an ignition transformer (hereinafter referred to as "transformer"), a primary coil bobbin is arranged coaxially with a core member as shown in FIG. 3, and a primary coil is wound on the bobbin. However, there is a structure in which a secondary bobbin is arranged on the outside of the primary coil in the coaxial direction and the secondary coil is wound on top of it. However, depending on the conditions of the fuel or the characteristics of the ignition device, 2 When it is necessary to shorten the rise time of the output voltage on the secondary side, in order to reduce the time constant of the primary and secondary coils of the transformer, a configuration that reduces the number of turns of the primary coil is used as shown in Fig. 4. is there.

As another method for reducing the rise time of the output voltage on the secondary side, the primary coil shown in FIG. 4 is a copper wire with a large wire diameter even if the number of turns is the same, and the cross-sectional area of the winding is Also, there is a configuration for increasing the volume.

As another method, as shown in FIG. 6, a configuration in which a plurality of layers of primary coils connected in parallel are wound on the primary coil is conceivable.

Further, there is a configuration shown in FIG. 5 in which a secondary coil is sandwiched between primary coils as is done in a low voltage transformer.

[0006]

[Problems to be solved by the device]

 In the method of reducing the number of turns of the primary coil described above, the coupling between the primary coil and the secondary coil may be reduced, or the copper loss and the iron loss of the transformer may be unbalanced, resulting in a reduction in the output of the transformer. is there.

Further, when the winding is made thicker or a multi-layer primary coil is wound, the wire diameter of the primary coil and the number of winding layers are limited unless there is sufficient space between the primary bobbin and the secondary bobbin. In some cases, the cross-sectional area and volume of the winding required to obtain sufficient coupling with the secondary coil cannot be obtained.

Further, when the winding is wound in multiple layers, improvement of copper loss can be expected, but it is difficult to obtain a sufficient winding cross-sectional area for improvement of coupling between the primary coil and the secondary coil. , I can't expect a big effect.

Further, when the secondary coil is sandwiched by the primary coils, the transformer main body becomes large in size in order to maintain insulation between the high voltage portion and the low voltage portion.

Therefore, an object of the present invention is to solve the above-mentioned problems in a boosting transformer, for example, an ignition transformer, and to shorten the rise time without lowering the output of the secondary voltage.

[0011]

[Means for Solving the Problems]

 In this invention, when it is necessary to reduce the number of turns of the primary coil, a plurality of primary coil units having the same number of turns are juxtaposed along the axial direction of the primary coil and are connected in parallel.

[0012]

【Example】

 In FIG. 1 showing the present invention, a primary bobbin 2 and a primary coil 34 wound around this are coaxial with an axis of a core member 1 made of a magnetic material. The primary coil 34 is formed by arranging two primary coil units 31 and 32 having the same number of turns in parallel. The primary coil units 31 and 32 are connected in parallel as shown in FIG. 2, and each has the same number of turns as the primary coil 30 shown in FIG.

A secondary bobbin 4 coaxial with the primary coil 34 is provided at a predetermined interval, and a secondary coil 5 is wound on the secondary bobbin 4. The secondary coil 5 corresponds to the secondary coil 5 in the primary coil 34. A predetermined turn ratio is given in proportion to the number of turns of one primary coil unit.

If necessary, a plurality of layers of primary coils, which are connected in parallel and have the same number of turns, may be wound on the primary coil units 31 and 32.

[Action]

 Next, the operation of the present invention will be described. The voltages output to the respective secondary coils of the five transformers D0 to D4 shown in FIG. 1 and described in the above embodiment and the five transformers D5 to D9 shown in FIG. 4 and also described above. , And rise time (from 5 KV to 30 KV) are measured by the circuit shown in FIG. 7, and the results are shown in Table 1 and Table 2, respectively. The primary coil 30 and the primary coil units 31 and 32 both have a wire diameter of 0.58 mm and have 30 turns, and the secondary coil 5 has a wire diameter of 0.07 mm and have 6391 turns.

[0015]

[Table 1]

[0016]

[Table 2]

[0017]

[Effect of the device]

 The experimental results shown in Tables 1 and 2 can be obtained by using the configuration of the present invention when the time constant of the transformer is reduced in order to shorten the rise time of the secondary voltage of the transformer. As this experimental result shows, the rise time can be shortened without changing the voltage characteristics output from the secondary coil.

[Brief description of drawings]

FIG. 1 is a sectional view of a transformer showing an embodiment of the present invention.

FIG. 2 is a connection diagram of a primary coil of the present invention.

FIG. 3 is a sectional view of a conventional transformer.

FIG. 4 is a cross-sectional view of a transformer of the second example of the related art.

FIG. 5 is a cross-sectional view of a transformer of a third example of the related art.

FIG. 6 is a cross-sectional view of a conventional transformer of the fourth example.

FIG. 7 is a circuit diagram used in an experiment of the present invention.

[Explanation of symbols]

 1 Core member 2 Primary bobbin 4 Secondary bobbin 5 Secondary coil 30,34 Primary coil 31,32 Primary coil unit

Claims (1)

1. A utility model registration claim 1. A primary bobbin is arranged coaxially with an axis of a core member, a primary coil is wound around the primary bobbin, and the primary coil is provided at a predetermined interval. In a transformer in which a secondary bobbin is provided coaxially with a core member and a secondary coil is wound on the secondary bobbin, the primary coil is divided into a plurality of primary coil units having the same number of turns, and these units are axially arranged. Transformers for boosting, which are arranged in parallel with each other and connected in parallel with each other.