JPS6031209Y2 - Rotating variable resistor - Google Patents

Description

[Detailed description of the invention] The present invention relates to a rotary variable resistor, and its purpose is to provide a small and relatively large current resistance device with a heat sink to prevent failures due to heat generation and heat accumulation in the resistor, etc. The aim is to provide a rotary variable resistor that can flow .

The first embodiment of the present invention (in the case of a dual rotary variable resistor)
To explain with reference to FIGS. 4 to 4, reference numeral 1 denotes a short, generally cylindrical cover formed from a metal plate with open ends at both ends;
It is formed by punching out a rectangular original plate having a plurality of protruding parts 2a, 2b and protrusions 3 on both sides, rolling it up, and joining both ends of the plate at a joining part 1a by appropriate means, as shown in FIG. As shown in FIG. 2, overhangs 2a, 2a,
2bt 2b are arranged, and l pairs of projecting pieces 3, 3 are provided protruding from each projecting portion.

The cover 1 includes insulating substrates 4a, 4b and a heat sink 1, which will be described later.
It plays the role of fixing 2゜17 into one body, and the role of covering the main parts.

4a and 4b are insulating substrates (approximately 1.5 cm thick) made of heat-resistant insulating material, such as ceramic, and each has a shaft hole 5 for inserting an operating shaft 16, which will be described later, as shown in FIG. , a substantially horseshoe-shaped resistor 6 and a Y-shaped current collector 7 are provided on one surface, both ends of the resistor 6 are connected to terminals 8 and 10, and the current collector 7 is connected to the center terminal 9. , arc-shaped notches 11, 11 are provided on both sides for engaging with the protruding parts 2a, 2b of the cover 1, respectively.

Reference numeral 12 denotes a front heat dissipation body made of die-casting, for example, zinc die-casting, and a substrate portion 13 in the shape of cutting a portion of a disc.
A plurality of heat dissipation fins 14a, 14b are provided on one surface of the shaft, and a bearing 15 for rotatably supporting the operating shaft 16 is integrated into one body.

Note that 15a is a threaded portion into which a nut (not shown) is screwed when attaching the resistor to a panel or the like.

Similar to the heat sink 12, 17 is a rear heat sink made of zinc die-casting, for example, and includes a substrate portion 1 in the shape of a partially cut disk.
Multiple fins 19at 1 for heat radiation on one side of 8
9b, and a shaft hole 20 is bored in the base plate portion 18.

It goes without saying that the heat sinks 12 and 17 may be formed by a casting method other than die casting, or by machining.

In addition to the above-mentioned parts, the variable resistor of the above embodiment has an insulating substrate 4a.
, are in sliding contact with the resistors 6, 6 provided on 4b, respectively, and
Two sliders are used in which the current collectors 7 and 7 are in contact and conductive, respectively, but these are not directly related to the present invention and will therefore be omitted.

Next, to explain the assembly of the variable resistor of the above embodiment, first, the overhanging parts 2a, 2a of the cover 1 are connected to the insulating base 4a.
At that time, the substrate portion 1 of the heat dissipating body 12 is attached to the outer surface thereof with the surface on which the resistor 6 is provided inside.
3 and the shaft hole (not shown) of the bearing 15 and the substrate 4a.
By aligning the shaft holes 5 of the fins 14b and the protrusions 3 provided on the protruding parts 2a and 2a of the cover 1 on both sides of the bases of the fins 14b and 14b, the insulating substrate 4a and the heat dissipating body 12 are separated. At the same time, it is fixed to the cover 1.

Next, the operating shaft 16 is inserted through the shaft hole 5 of the substrate 4a and the shaft hole of the bearing 15, and two sliders (
(not shown), then engage the insulating substrate 4b with its notches 11.11 to the overhangs 2a, 2b of the cover 1,
At that time, the resistors 6°6 of the substrates 4a and 4b are mounted facing each other, and then the substrate portion 18 of the heat sink 17 is attached to the outer surface of the substrate 4b.
are brought into close contact with each other, and the shaft hole 20 of the base plate 4b is aligned with the shaft hole 5 of the substrate 4b, and each protruding piece 3 provided on the protruding parts 2b, 2b of the cover 1 is bent to both sides of the base of the fins 19b, 19b. The substrate 4b and the heat sink 17 are fixed to the cover 1 at the same time, and the insulating substrate 4aw4b and the heat sink 1 are fixed by the cover 1.
2.17 is fixed as one body and the assembly is completed.

In the variable resistor of the embodiment assembled as described above, two sliders are located between the insulating substrates 4a and 4b, and one slider and the substrate 4a allow the front-stage resistor to be connected to the other slider. The actuator and the substrate 4b form a rear-stage variable resistor, and the operating shaft 16 rotates within an angular range regulated by a stopper (not shown).At the same time as the operating shaft 16 rotates, the two sliders rotate. The terminals 8. rotate and slide into contact with the resistors 6, 6 of the substrates 4a, 4b.
10 and the center terminal 9 changes.

Although the above embodiment shows the case of two variable resistors, if only one variable resistor is used, only the front stage variable resistor may be used. In that case, the rear heat sink 17 is do not need.

It is also possible to separate the front heat dissipation body and the bearing and make them into one body by strong fitting or other means, but this increases the processing time and the number of parts, so die-casting or other methods are used. It is better to form it in one piece using a casting method.

The rotary variable resistor of the present invention has the following features based on the above, and improves the reliability and productivity of the variable resistor.

(a) Since the heat sink is closely attached to the opposite side of the insulating substrate to the surface on which the resistor is installed, and the heat-resistant insulating substrate is relatively thin, the heat generated in the resistor can be easily insulated. The heat is conducted through the substrate to the heat dissipation body, and is emitted into the air from its plurality of fins.

Therefore, the rise in temperature of the heat generating part and the accumulation of heat in the resistor are suppressed, and accidents such as burnout of the heat generating part and seizure of the slider can be prevented.

(b) Since the bearing of the operation shaft is integrated with the heat sink, the number of parts and processing steps are reduced, and assembly is easy.

(c) Ceramic insulating substrates are fragile and easy to hang, but because they are sandwiched between the cover and the heat sink and fixed by bending the protrusion provided on the cover to the outside of the base of the heat sink, it is possible to partially Since no pressure is applied to the parts, they are not easily destroyed, are easy to assemble, and the number of defective products is significantly reduced, improving productivity.

[Brief explanation of the drawing]

Figures 1 to 4 are diagrams showing an embodiment of the present invention, a dual rotary variable resistor, in which Figure 1 is a side view, Figure 2 is a top view, and Figure 3 is a side view.
The figure is a rear view, and FIG. 4 is an exploded perspective view of the cover 1 and insulating substrates 4a and 4b. 1...Cover, 4a, 4b...Insulating substrate, 6...Resistor, 12...Front heat sink, 13... Substrate part, 14a. 14b...Fin for heat dissipation, 15...Bearing, 16...Operation shaft, 17...Rear heat sink, 18...Substrate Part, 19a. 19b...Fin for heat radiation.

Claims (2)

[Scope of utility model registration request] (1) A cover with open ends at both ends, an insulating substrate made of a heat-resistant insulating material with a resistor formed on one surface, and a bearing for rotatably supporting the operating shaft are integrally formed. A heat dissipation body provided with a plurality of fins for heat dissipation,
The heat sink and the other surface of the insulating substrate on which the resistor is not formed are mounted in close contact, and the heat sink and the insulating substrate are fixed by a protrusion formed on one open end of the cover. A rotary variable resistor characterized by: (2) At the other open end of the cover whose both ends are open ends, another insulating substrate having a resistor provided on one surface is arranged so as to face the resistor of the insulating substrate, and another insulating substrate 2. The rotary variable resistor according to claim 1, which is a dual rotary variable resistor, characterized in that another heat sink is attached closely to the other surface of the rotary variable resistor.