JPS63244807A - Sliding contact apparatus - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention applies to volume switches, potentiometers, and trimmers used for detection, control, setting, oscillators, etc. in measuring instruments, various machines, etc. (a type of variable resistor)
This paper relates to improvements to sliding contact devices used in, etc.

(Prior art and its problems) Sliding contact devices conventionally used in the above-mentioned polyneme switches, potentiometers, trimmers, etc. are made by forming a thick film resistor pattern on a resin substrate using a resistive paste such as carbon (C). It consists of a wiring board formed by forming a wiring board, and a sliding contact made by caulking or welding an Ag contact material to a spring terminal material that can slide against the thick film resistance pattern of the wiring board. However, this sliding contact device was prone to noise generation (also, the contact resistance was somewhat high and varied, making it unstable and lacking in contact reliability).

For this reason, the parts of the carbon thick film resistor pattern on the resin substrate that slide against the sliding contacts should be replaced with Ag-resin-based conductive paste and cured, or the parts that slide with the sliding contacts of the thick film resistor pattern Contact reliability was improved by layering and curing Ag-resin conductor paste.

However, since the thick film conductor bag and the contact material are the same type of combination, there is a problem that adhesion and peeling easily occur, accelerating wear and shortening the service life.

(Object of the Invention) An object of the present invention is to provide a sliding contact device that can solve the above problems.

(Means for Solving the Problems) A sliding contact device of the present invention for solving the above-mentioned problems includes forming a thick film resistor pattern using a resistor paste on a resin substrate. A wiring board formed of a thick film conductor pattern formed of an Ag-resin conductor paste connected to the wiring board, and a wiring board made of Ag-cadmium 0.5 so that it can slide against the thick film conductor pattern of the wiring board. ~15wt%
The contact member is comprised of a sliding contact attached to a spring terminal member.

In the sliding contact device of the present invention, the contact material of the sliding contact is A
The reason for setting g-cadmium to 0.5 to 15 wt% is that Ag
If the cadmium content is less than 0.5 wt%, the lubricating effect will be weak, and adhesion and peeling will occur when the sliding contact contacts the Ag-resin thick film conductor pattern on the resin substrate. This is because if it exceeds this, it will cause noise generation.

(Function) In the sliding contact device configured as described above, the Ag-cadmium 0.5 to 15 wt% contact material of the sliding contact easily slips during the contact action between the sliding contact and the thick film conductor pattern on the resin substrate. , there is no adhesion to the Ag-resin thick film conductor pattern, and there is almost no peeling of the pattern.
Reduced wear and better contact.

(Example) To explain an example of the sliding contact device of the present invention, a carbon resistance paste with a width of 3 mm is placed on the outer periphery of an epoxy resin substrate 1 having a thickness of 0.6 am and a diameter of 30 fins as shown in the figure. was screen printed and cured at 130°C to form a thick film resistor pattern 2 with a thickness of 10μ.
A thick film conductor pattern (width 0.2 mm, length 71 mm, thickness 10 μm) is formed at 0.2 fin intervals by screen printing Ag-resin conductor paste in the circumferential direction and hardening it at 130°C. A wiring board 4 was formed by forming an Ag-tree (Jliff 26 wt%) 3. On the other hand, two types of sliding contacts 5 are arranged to slide oppositely to the thick film conductor pattern 3 of the wiring board 4.
are Ag-cadmium lht% and Ag-cadmium 3w
t%-nickel 0 and 1 wt% contact wire (diameter 1
．． Head diameter 31 m, head thickness 0.6 made from 5fl)
fi, two types of rivet contacts 6 with a leg diameter of 1.5mm and a leg length of 1.5tm, each with a width of 4mm and a thickness of 0.151m.
It is inserted into a contact mounting hole of a spring terminal material 7 made of Cu and then tightened.

The sliding contact device of Example 1.2 configured in this way,
A conventional sliding contact device consisting of a sliding contact having an Ag contact material facing a thick film conductor pattern 3 made of 26 wt% Ag-resin on the same wiring board 4 as in the example was subjected to sliding opening and closing under the following test conditions. When the test was conducted, the results shown in the table below were obtained.

Test conditions Contact crab 10g, operation: rotating reciprocating type (55 degrees), drive =
60 stroke/min, energization: 12■, 100mA (
As is clear from the above table, the life of the sliding contact device of Example 1.2 is almost twice as long as that of the conventional sliding device. This is because the Ag-cadmium 0.5 to 15 wt% contact material of the sliding contact 5 is slippery, so it does not adhere to the opposing Ag-resin thick film conductor pattern 3 (and the pattern may peel off). This is because there is no problem, and wear is also reduced.

Note that the above-mentioned lifespan is due to wear of the thick film conductor pattern 3.
The evaluation was made based on the case where the sliding contact 5 came into contact with the resin substrate, resulting in an oven state (infinite contact resistance), and the case where a short circuit occurred due to clogging of the slit between the thick film conductor patterns 3.

Although the wiring board 4 of the sliding contact device in the above embodiment is circular, it may also be rectangular. In that case, the thick film resistor pattern is preferably formed at one end of the rectangular wiring board, and the thick film conductor patterns are preferably connected to the thick film resistor pattern and formed in parallel at regular intervals in the longitudinal direction thereof. The sliding contact is slidable in the longitudinal direction of the thick film resistor pattern, facing the thick film conductor pattern. Further, a wiring board in which a thick film resistor pattern reciprocated back and forth in a bellows shape is formed on a resin substrate, and thick film conductor patterns are formed on the resin substrate by arranging them at regular intervals;
A sliding contact device comprising a sliding contact slidably facing the thick film conductor pattern of the wiring board may also be used.

Furthermore, as in Example 2, a part of cadmium is added to 0.01~
It may be replaced with an iron group element within a range of 1 wt%.

(Effects of the Invention) As can be seen from the above explanation, in the sliding contact device of the present invention, since 0.5 to 15 wt% of Ag-cadmium in the sliding contact is slippery, the Ag-resin conductor on the resin substrate is used in the contact action. There is no adhesion to the pattern, there is almost no peeling of the pattern, and wear is reduced, resulting in good contact.

Therefore, the contact efficiency is improved and the life of the sliding contact device is significantly extended.

[Brief explanation of drawings]

The figure is a schematic diagram showing an embodiment of the sliding contact device of the present invention.

Claims (1)

[Claims] A wiring board in which a thick film resistor pattern is formed using a resistor paste on a resin substrate, and a thick film conductor pattern is connected to the thick film resistor pattern using an Ag-resin conductor paste, and this wiring board Ag-cadmium 0.5-15wt% so that it can slide against the thick film conductor pattern of
1. A sliding contact device comprising a sliding contact in which the contact member is attached to a spring terminal member.