JPH043457Y2 - - Google Patents

Description

[Detailed description of the invention] [Purpose of the invention] (Field of industrial application) The present invention relates to a rotary transformer used in magnetic recording and reproducing devices, etc., and in particular, to a fixing structure between a core and a terminal block that constitute a rotary transformer. This is related to the improvement of.

(Problems to be solved by conventional techniques and ideas) This type of rotary transformer has an inner core and an outer core arranged concentrically with a minute gap, and is installed in the cylinder head of a magnetic recording/reproducing device. Strict dimensional accuracy is required for both the inner and outer cores. In particular, if more adhesive than necessary is attached to the bonded portions between the two cores and the respective terminal blocks provided with lead wires, the desired dimensional accuracy cannot be obtained.

Conventional examples of such bonding structures between the inner core and the terminal block, and between the outer core and the terminal block will be explained below, with each case being separated.

FIGS. 5a and 5b show the state of adhesion between the inner core 30 and its terminal block 31 in the prior art.

Annular grooves 34a to 34d are formed in parallel to each other at predetermined intervals on the outer peripheral surface of the inner core 30, and a winding 35 is disposed in each of the annular grooves 34a to 34d.

A terminal block 31 is adhesively fixed to the upper end of the inner core 30 in FIG. 5a. That is, this terminal block 31 includes a ring portion 36 that can be fitted into the inner core 30, and a portion of the ring portion 36 that extends upward from the upper end surface of the ring portion 36, and a portion of the periphery thereof is connected to the inner periphery of the ring portion 36. Four lead wire holding portions 37a formed to protrude further inward from the surface
~37d and these lead wire holding parts 37a~37
d, and the inner circumferential surface of the ring part 36 and the lead wires 38 held at the ends thereof.
Lead wire holding parts 37a to 37 protruding inward from
This terminal block 3 is attached while applying adhesive to the protruding part of d.
1 is fitted onto the inner core and the two are adhesively fixed.

However, in the case of such a configuration, the adhesive adhered to the inner circumferential surface of the ring portion 36 leaks onto the circumferential wall surface of the inner core 30 and hardens, as shown in an enlarged view in FIG. 5b. Forming the hardened portion 39a or forming the lead wire holding portions 37a to 3 of the inner core 30
The adhesive leaks out to the end face portion other than the portion that contacts 7d and hardens, forming a hardened portion 39b. There is a problem in that sufficient dimensional accuracy cannot be achieved when attaching to the head section.

On the other hand, a similar problem occurs in the adhesive structure between the outer core 40 and the terminal block 41 thereof.

That is, as shown in FIGS. 6a and 6b, the conventional outer core 40 is formed into a cylindrical shape so that the inner core 30 can be fitted loosely with a small gap therebetween, and the inner peripheral surface of the outer core 40 has a cylindrical shape. 30 annular grooves 34a~
Annular grooves 44a to 44d are provided at predetermined intervals and arranged in parallel so as to correspond to each of the annular grooves 34d, and an outer winding 45 is disposed in each of these annular grooves 44a to 44d. This outer core 4
A terminal block 41 is adhesively fixed to the lower end of the terminal block 0.

This terminal block 41 integrates an outer ring portion 46 that can be fitted onto the outer periphery of the outer core 40 and four lead wire holding portions 47a to 47d that protrude downward from the outer periphery of the outer ring portion 46. It is constructed by molding and holding the lead wires 48 by lead wire holding parts 47a to 47d, respectively. A tapered part 49 is formed at the upper part of the inner circumferential side of the outer ring part 46 for adhering an adhesive over the entire circumference, and the terminal block 41 is fitted to the outer circumference of the lower end of the outer core 40 and By applying adhesive to the tapered portion 49 using a dispensing machine or the like, these two parts are bonded and fixed.

However, such an outer core 40 and terminal block 41
In the adhesive structure with the terminal block, the adhesive bulges upward from the tapered part 49, and as a result, the adhesive also adheres to the wall surface of the outer core 40 above the tapered part 49 and hardens, thereby bonding the outer core 40 and the terminal block. It is difficult to make the intersection with 41 a right angle, and the same problem as in the case of the inner core 30 occurs.

In any of the above cases, it is possible to take measures to remove the hardened adhesive, but
It is generally difficult to completely remove an adhesive once it has hardened.

In addition, the terminal block 31, the inner core 30, and the terminal block 4
Considering the adhesive strength between the inner core 30 and the outer core 40, it is not necessarily necessary to apply the adhesive all the way around the inner core 30 and the outer core 40, but to apply the adhesive partially to the outer peripheral surfaces of each. It has been experimentally confirmed that sufficient adhesion strength can be obtained even if the method is used. Although not shown in FIGS. 5 and 6, in reality, the ends of each winding 35 arranged in the inner core 30 are connected to each lead wire 38, and the ends of each winding 45 arranged in the outer core 40 are connected to each lead wire 38. It goes without saying that the parts are respectively connected to the respective lead wires 48.

[Structure of the invention] (Means for solving the problems) The rotary transformer of the invention includes an outer core and an inner core that are coaxially arranged with a predetermined gap, and a terminal block that is adhesively fixed to each of these cores. An arbitrary number of notch retention portions for adhesive are provided on the peripheral surface of the terminal block at least in a portion facing the wall surface of the core, and an adhesive is attached to the notch retention portions to connect the core and the terminal block. It is fixed with adhesive.

(Function) According to the rotary transformer having the above configuration, the core and its terminal block are adhesively fixed using an adhesive that adheres to an arbitrary number of notch retaining portions provided on the terminal block. The adhesive state between the inner core and its terminal block is such that when the adhesive heats and hardens, the adhesive becomes viscous and flows into the small gap between the outer circumferential surface of the core and the inner circumferential surface of the ring part due to capillary action. ) There is no protrusion.

Further, the bonding state between the outer core and its terminal block is also the same as in the case described above.

(Example) Examples of the present invention will be described below.

FIG. 1 shows an embodiment in which the present invention is applied to an inner core and its terminal block. In this figure, parts having the same functions as those in the conventional example shown in FIGS. 5a and 5b are denoted by the same reference numerals, and detailed explanation thereof will be omitted.

The difference between the embodiment shown in FIG. 1 and the conventional example shown in FIGS. 5a and 5b is that the inner peripheral surface of the ring portion 36 of the terminal block 1 facing the inner core 30 is divided, for example, into four parts around the entire circumference. Four crescent-shaped adhesive notch holding portions 2 are provided, and the notch holding portions 2 are
The terminal block 1 and the inner core 30 are adhesively fixed by applying an adhesive to the terminal block 1 and the inner core 30. FIG. 2 shows a state in which adhesive is applied to this notch retaining portion 2. As shown in the figure, the adhesive hardens in a portion extending from the deepest part of the inclined surface of the notch retaining part 2 to the wall surface of the inner core 30 facing the notch retaining part 2 due to its liquid-simulating property. Therefore, the hardened adhesive does not bulge out toward the upper end surface of the ring portion 36 and the upper end surface of the inner core 30.
As a result, it is possible to avoid the problem of the hardened adhesive being exposed on the end surface of the inner core 30 and making it impossible to ensure dimensional accuracy as in the conventional example shown in FIGS. 5a and 5b.

In this case, the adhesive passes between the ring portion 36 and the outer circumferential wall surface of the inner core 30 and then further onto the inner core 3.
In order to prevent the liquid from flowing out onto the lower wall surface (unnecessary part) of the inner core 30, the smaller the difference in dimension between the outer diameter of the inner core 30 and the inner diameter of the ring part 31, the better.

As the above-mentioned notch retaining section, modifications shown in FIGS. 3a to 3d can be cited.

Figures 3a and 3b show a notch retaining portion 2A having a triangular shape.
FIGS. 3c and 3d show the notch retaining portion 2B having a rectangular cross section.

In the case of such notch retaining parts 2A and 2B as well, the same operation and effect as in the case of the notch retaining part 2 shown in FIGS. 1 and 2 can be exhibited.

Next, an embodiment in which the present invention is applied to an outer core and its terminal block will be described with reference to FIGS. 4a and 4b. In the embodiment shown in FIGS. 4a and 4b, parts having the same functions as those shown in the conventional example shown in FIGS. 6a and 6b are denoted by the same reference numerals, and detailed explanation thereof will be omitted.

The difference between this embodiment and the one shown in FIGS. 6a and 6b is that the terminal block 11 is constructed in substantially the same manner as the terminal block 41, and that the entire circumference of the ring part 46 is 44 mm on the tapered part 49 side. This is because four U-shaped notch retaining portions 12 are formed so as to be equally divided.

As shown in an enlarged view in FIG. 4b, the cured state of the adhesive in this notch retaining part 12 is such that the adhesive stays on the bottom 12a side of the notch retaining part 12 due to its pseudo-liquid property, and a part of the adhesive is tapered. As a result, the hardened adhesive does not exceed the upper end surface of the ring section 46 and adhere to the upper wall surface of the outer core 40, and the upper end surface of the ring section 46 and the outer core 40 Both are adhesively fixed with the intersection with the wall at 90°.

Therefore, this outer core 40 and terminal block 11
Sufficient dimensional accuracy can be ensured when assembling the cylinder head into the cylinder head.

It goes without saying that the present invention is not limited to the embodiments described above, and that various modifications can be made within the scope of the invention.

For example, the number of notch holding parts mentioned above is not limited to four, but six.
It is also possible to use an arbitrary number such as 1, 8, etc.

[Effects of the invention] According to the present invention detailed above, by providing the terminal block for the core with an adhesive notch holding portion facing the wall surface of the core, unnecessary curing caused by the curing of the adhesive is avoided. Since there is no bulge, it is possible to provide a rotary transformer that can ensure sufficient dimensional accuracy during assembly.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing an embodiment in which the present invention is applied to an inner core and its terminal block, Fig. 2 is a partial cross-sectional view of the same as above, and Figs. 3 a and b are respective examples of the embodiment shown in Fig. 1. FIGS. 3c and 3d are a perspective view and a cross-sectional view of a main part showing a modified example of the notch retaining part, respectively, and FIG. 5 is a perspective view of the present invention applied to an outer core and its terminal block, FIG. 4b is a partial cross-sectional view of the same as above, and FIG. 6b is a sectional view of the same as above, FIG. 6a is a perspective view showing a conventional outer core and its terminal block, and FIG. 6b is a sectional view of the same. 1... Terminal block for inner core, 11... Terminal block for outer core, 2, 12... Notch holding part, 30...
Inner core, 40...outer core.

Claims (1)

[Claims for Utility Model Registration] (1) In a rotary transformer having an outer core and an inner core coaxially arranged with a predetermined gap, and a terminal block adhesively fixed to both cores, at least the wall surface of the core 1. A rotary transformer characterized in that an arbitrary number of notch retention portions for adhesive are provided on the peripheral surface of the terminal block facing the terminal block, and an adhesive is attached to the notch retention portions to adhesively fix the core and the terminal block. (2) The notch retaining portion has a crescent shape, a square shape,
The rotary transformer according to claim 1, which has a shape selected from triangular shapes. (3) The rotary transformer according to claim 1, wherein a plurality of the notch holding portions are provided on the outer core terminal block.