JPH0136965B2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a method for manufacturing a discharge lamp ballast.

In this type of ballast, each core block is constructed by laminating a plurality of magnetic steel plates, and these blocks are brought into contact with each other to form one closed magnetic circuit core. Then, a coil is wound around the iron core block. For example, a core block 1 shown in FIG. 1 is T-shaped, and other L-shaped core blocks are abutted on both sides to form a Japanese-shaped core. Then, a coil 3 is wound around the central leg 2 of the iron core block 1.

By the way, in this kind of iron core block 1, both sides 2A of the central leg 2 are integrated by welding in order to suppress vibration of each steel plate. Also, center leg 2
Both sides (between both sides 2A) 2B are adhered with adhesive. However, in the past, since adhesive was simply applied, it was difficult for the adhesive to penetrate between the various steel plates, and therefore sufficient adhesion could not be achieved. Therefore, it has been unavoidable that there is a limit to the ability to suppress noise by applying adhesive.

An object of the present invention is to reduce noise caused by vibration even when bonding with an adhesive.

Embodiments of the invention will be described with reference to the drawings. A bridge gap 4 is formed on the central leg 2 of the iron core block 1 around which the coil 3 is wound. Normally, this type of bridge gap is formed in the center of the central leg 2, but according to the present invention, the bridge gap 4 is formed in the shape of a notch on both sides 2B of the central leg 2, as shown in the figure. The coil 3 is composed of a cylindrical winding core 5 made of thick paper and an electric wire 6 wound around the core in multiple layers. Then, the winding core 5 is fitted onto the center leg 2 as shown in the figure. As described later, the coil 3 is clamped by applying force from above and below along the stacking direction of the steel plates, and in that state, it is clamped from both directions toward the side surface 2B (in the example shown in Fig. 1, as shown by the arrow P). Apply pressure (from above and below).

Figure 3 shows a partially enlarged view. This figure shows the state before pressure is applied from above and below. The bridge gap 4 is filled in advance with an adhesive 7 such as an epoxy resin. Then, as described above, the coil 3 is pressurized along the direction of arrow P. Due to this pressurization, each wire 6 falls between the wires of the adjacent layer, thereby reducing the coil cross-sectional area. This advantageously reduces the occupation rate of the electric wires.
On the other hand, the core 5 is pressed against the side surface 1B by the above-mentioned pressure and its thickness is reduced, but the portion facing the bridge gap 4 is not pressed against the side surface 1B but is pushed into the bridge gap 4. FIG. 4 shows this state.

Since the internal adhesive 7 is pressurized by such partial pushing of the core 5, the adhesive 7 is press-fitted into the gap between the stacked steel plates. As a result, the steel plates are reliably bonded and fixed together by the press-fitted adhesive.
By fixing in this manner, the vibration of the steel plate is suppressed, and the noise caused by the vibration is sufficiently suppressed. According to experiments conducted by the present inventors, it has been confirmed that while the conventional method of applying the adhesive produced 32 horns of noise, the method of the present invention reduced this noise to 27 horns.

As detailed above, according to the present invention, the adhesive bonding of the steel plates constituting the iron core block is ensured by press-fitting the adhesive between each steel plate, thereby making it possible to suppress noise caused by vibration as much as possible. It produces the desired effect.

[Brief explanation of drawings]

FIG. 1 is a plan sectional view for explaining the process of carrying out the invention, FIG. 2 is a perspective view of the iron core block, and FIGS. 3 and 4 are partially enlarged sectional views. 1... Iron core block, 3... Coil, 4... Bridge gap, 5... Winding core, 6... Electric wire, 7...
…glue.

Claims (1)

[Claims] 1. A notch-shaped bridge gap is provided on the side surface of the iron core block around which the coil is wound. After filling the bridge gap with adhesive in advance, the coil formed by winding the electric wire around the cylindrical core is attached to the core. The core is inserted into the block and pressure is applied from the outer periphery of the coil toward the side surface of the core block, and by this pressure, the core is locally pushed into the bridge gap and the adhesive is applied to the core block. A method of manufacturing a discharge lamp ballast by press-fitting it between the laminated surfaces of the constituent steel plates.