JPS60162448A - Small-sized motor - Google Patents

Abstract

PURPOSE:To prevent the surface of commutator segments from damaging by friction by mounting a member which impregnates monoalcohol having -OH group on part in a motor case. CONSTITUTION:A felt 14 is disposed near the side 3 of a commutator on a bracket 12. The felt 14 has a linear carbon bond or a side chain, and a sole or a plurality of monoalcohols having a -OH group. The atmosphere in a motor case made of a motor housing 13 and a bracket 12 becomes vapor atmosphere with the monoalcohols.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a small motor used for driving a tape in, for example, a tape recorder or a video tape recorder.

Conventional Structures and Problems There are generally two types of brushes used in small motors. One is a conductive material with elasticity, such as copper, beryllium-copper, copper-titanium alloy, phosphor bronze, nickel silver thin plate material, or wire material, and noble metal alloy (such as Au, Pd, P
t, Ag, Cu, etc. and their alloys) cladding 1,
Alternatively, it is a structure in which a part of a thin plate material or wire rod is joined by means such as spot welding, and the other is a structure in which a part of the thin plate material or wire rod mentioned above is joined with a sintered carbon brush (for example, C carbon, A g Carboy, Cu carboy, A
gCuC carbon, and those materials include SiC, MoS
2゜pb, carbon brushes containing additives such as epoxy resins) are formed using conductive adhesive, spot welding, crimping, etc., but in small motors with these brushes, the commutator rotation is Sometimes, the commutator sliding part vibrates unnecessarily, which causes abnormal welding on the contact surface of the commutator sliding part with the commutator segment, and blackening (carbon and brush and commutator) caused by spark generation. (mixture of sliding wear particles generated between segments)
The generation of foreign matter that promotes abnormal phenomena often occurs and becomes a problem.

In brushes for small motors, the commutator sliding part that slides on the commutator segments is molded integrally with the plan base, which is supported by support means provided on the lid of the motor case, for example. . The contact between such a brush and a commutator segment is shown in FIG.

In FIG. 1, a bent commutator sliding portion 3 extends from a brush base 2 supported by a brush support means 1. This commutator has 3 sliding parts and 2 brush bases.
It has elasticity due to being bent from above, and is in contact with the commutator segment 4 in a pressed state. The pressing force can be determined by appropriately selecting the bending angle between the plan base 2 and the commutator sliding part 3.
It can be any value you want. Further, the commutator segment 4 is fixed to the motor rotating shaft 6 via an insulating cylinder 5, and rotates with the rotation of the motor.

Since the rotating commutator segment 4 and the commutator sliding part 3 are in sliding contact with each other, electrical sparks are likely to occur between them, and the generation of these electrical sparks can cause electrical noise and the commutator sliding part 3. Inconvenient conditions such as welding on the portion 3 will occur. The occurrence of this welding not only shortens the life of the brush, but also
If welding occurs at the position where it starts and leaves contact with each commutator segment 4 (section a in Figure 1), this welding will scrape and damage the surface of the commutator segment 4, and the surface of the commutator segment 4 will be damaged. Cutting debris accumulates in the gap between adjacent commutator segments 1-4, resulting in swarf. This has the disadvantage that the case and segments are electrically connected to each other, and the performance of the motor itself is degraded.

Incidentally, electric sparks are often generated at section a of the commutator sliding section.

The biggest cause of this is the vibration of the brush. That is, electric sparks frequently occur due to the vibration of the brush, which promotes the occurrence of welding and causes roughness of the sliding surface. As the roughness increases, the generation of electric sparks further increases, and eventually it becomes impossible to obtain the required characteristics of the motor, leading to the motor starting and stopping.

Generally, the material of the commutator sliding part 3 is a precious metal alloy brush or a sintered carbon brush as described in item 111, and the material of the commutator segment 4 is AgCu.
, AgCd , AgCuCd , Cu , Au alloys.

AqPd alloy, AgCuTf alloy, etc., and when a noble metal alloy brush is used, the sliding resistance is as high as 1.0 because the two have almost the same quality, and scratches occur at the sliding interface. This is an easy disadvantageous combination. Also,
When using a sintered carbon brush, the sliding resistance will be lower than when using a stable metal alloy brush, but there is a risk of scratches, and the composition of the carbon brush contains impurities such as 3102, and as with the elbow metal alloy bluff, scratches occur at the sliding interface.

It's an easy and profitable union.

The structure shown in Fig. 2a does not have a means to suppress the electric sparks that cause these defects, that is, the commutator sliding part 3 does not have vibration damping measures (i'l et al. The sliding part of the commutator has a large vibration, so welding easily occurs even when used at room temperature, and the life is long.
What is the best quality? 4I is important. As shown in Figure 2, vibration prevention rubber 7 is installed on the commutator sliding part 3.
is pasted with adhesive 8 (=J Kedamono) has good vibration absorption at room temperature and can suppress the generation of sparks, but when the temperature reaches the upper limit of 60℃, the viscosity of the adhesive decreases significantly.
The adhesion force of the anti-vibration rubber Y to the sliding part decreases, the vibration absorbing ability decreases, the occurrence of -C sparks increases, and the product has a short life and unstable quality. Furthermore, as shown in FIG.
When the adhesive 8 is applied to both sides of the base material 10, the viscosity of the adhesive decreases to some extent when compared with the example shown in Figure 2 above. Although it is small, it is not sufficient, and it is not possible to obtain long life and high quality at high temperatures.

The ambient temperature for this device is -10°C to 160°C.
Many are used at ℃.

Purpose of the Invention The present invention aims to improve the sliding properties of the commutator sliding part and the ξ commutator segment, prevent shortening of the motor life due to scratch damage on the surface of the commutator segment, and also improve the performance of devices such as tape recorders. The present invention provides a high-performance small motor that can reduce wow and flutter when incorporated into a motor or the like.

Structure of the Invention In order to achieve the above object, the present invention provides a brush base made of a thin plate or linear metal elastic body, and a brush base extending from the brush base or fixed to a part of the brush base. In a small motor equipped with a brush having a commutator sliding part, a member impregnated with monoalcohol, such as felt, is fixed or crimped with adhesive to a part of the motor case, for example, near the commutator sliding part on the bracket. installation method or other means. This monoalcohol has no double bonds and does not yet have a benzene ring.
It is a mono-alcohol that has linear carbon bonds or side chains and has more H groups in its molecular structure, and 1
26 from a substance whose boiling point is close to 100℃ under atmospheric pressure
It is particularly effective to select a suitable one depending on the usage situation from 0°C. The structure is such that this monoalcohol turns into vapor depending on the ambient temperature, and the inside of the motor case is under an atmosphere of monoalcohol. Note that in order to simplify the motor configuration, a configuration may be used in which the monoalcohol is directly applied to the brush or commutator sliding portion.

DESCRIPTION OF EMBODIMENTS FIG. 3, FIG. 4, and FIG. 6 each show an embodiment of the present invention. Here, parts with the same names as those in FIG. 1 are given the same reference numerals, and 12 is a bracket for holding a brush etc., 13 is a motor housing, and 14 is felt impregnated with monoalcohol. Note that the commutator sliding portion 13 is made of a carbon brush. In the embodiment of FIG. 3, the felt 14 is placed near the commutator slide 3 on the bracket 12, while in the embodiment of FIG. 4, the felt 14 is mounted on the brush base 2.

Further, in the embodiment shown in FIG. 6, the motor housing 13 is equipped with a felt 14. In addition, in FIG. 6, 16 is a rotor core attached to the motor rotating shaft 6;
16 is a winding wound around the rotor core 15, 17 is a permanent magnet fixed to the inner surface of the motor housing 13, and 18 is a bearing that supports the motor rotating shaft 6.

In each of these embodiments, the commutator sliding part 3 is fixed to the tip of the brush base 2, but as shown in FIG. part, and felt 1 is placed on the sliding part.
4 may be equipped.

In either case, the purpose of the embodiments is to create a monoalcohol-based vapor atmosphere in the motor case, which causes the atmospheric gas to adsorb onto the surfaces of the brushes and commutator segments, but the means for achieving this are not limited to this. .

By the way, previous literature and experiments have shown that the commutator sliding part and the commutator segment are easily welded,
Also, the conditions in which welding, abnormal wear, and poor conduction are likely to occur are being clarified. Conditions where abnormalities are likely to occur are when unsaturated cyclic hydrocarbons exist or are adsorbed in the atmosphere of the sliding parts of the brush sliding part and the commutator segment, or in the commutator segment itself. be.

At this time, blackide (carbon and brush and commutator)
A foreign substance called a mixture of sliding wear particles generated between segments that promotes abnormal phenomena is generated.

This foreign material is caused by the fact that when unsaturated cyclic hydrocarbons are combusted by an arc between the sliding part and the commutator segment, the amount of carbon per unit volume is large, resulting in incomplete combustion;
Although this is due to the molecular structure of No. 1, it is thought that the bonding state of the produced carbon becomes dense, resulting in the formation of hard carbon.

In addition, in the atmosphere of hydrocarbons other than unsaturated cyclic hydrocarbons, and due to their molecular structure, the carbon produced is soft and does not lead to abnormal phenomena. The matter has been clarified. Based on these phenomena, we conducted a long-term operation experiment using a commutator segment that adsorbed a small amount of hydrocarbons. In this experiment, we found that: 0) There is a high probability that abnormal wear will occur in the commutator segment under high temperature and low humidity.

■ If about 10 μq of hydrocarbons are adsorbed in the commutator segment, abnormal phenomena in the commutator segment will be alleviated and the life of the small motor will be extended. (
However, this data is based on the case where there is no continuous replenishment of hydrocarbons. ) was obtained (the results of the experiment are shown in Figure 6) Therefore, in the present invention, in consideration of the above phenomenon, the results shown in Figures 3 and 4 were obtained.
As shown in the embodiment shown in FIG. 6, a felt 14 impregnated with monoalcohol is placed inside the motor housing 13 and the placket 12. These monoalcohols are unsaturated cyclic hydrocarbons.
Its molecular structure is the most different, and it is one of the most unusual phenomena.
It is the farthest thing from the hard blackide formation, and even if carbon is formed, it is extremely soft, reducing the sliding resistance of the commutator sliding part and the commutator segment.

With the above configuration, an atmosphere suitable for the vapor pressure of monoalcohols can be obtained in the motor case at high temperatures and low humidity where abnormal phenomena are likely to occur. Monoalcohols that do not have this two-ton bond, do not yet have a benzene ring, have a linear carbon bond, or have a side chain have an -OH group in their molecular structure. Due to its polar force, has an adsorption force on the metal surface through hydrogen bonding.

Adsorption by hydrogen bonds is adsorbed with more than twice as much force as the adsorbed organic gas due to van der Waals attraction, and can be said to be a stable adsorption state.

By adsorption of these monoalcohols, Pt, Au, and Pd.

The commutator segment and plan, which have a strong catalytic effect, are made of Ag, etc., as well as those made of Cu.
It also adsorbs to the surface of the sintered carbon brush and other metal surfaces, preventing highly reactive gases (styrene monomer, toluene, etc.) from adhering to the surface.

This is because the adsorption power of the -OH group results in stronger hydrogen bond adsorption than, for example, van der Waals adsorption of styrene monomer or toluene. Still, grab.

Even if combustion occurs in the arc between the commutator segments, monoalcohols have oxygen in their molecular structure, so there is almost no tar formation due to incomplete combustion, and black oxides that cause poor contact occur. It produces very little, burns well, and does not cause contact failure.

Moreover, for small motors whose normal operating environment range is -10°C to +60°C, substances with a boiling point at 1 atm of around 100°C, 260°C are particularly effective, and are listed by type of monoalcohol. Then, ■ n-probyl alcohol ・・・97.2℃ (boiling point under 1 atmosphere) ■ Inbutyl alcohol ・・・106°～1
09℃ (boiling point under 1 atmosphere) ■ In-amyl alcohol...128°~13
2℃ (boiling point under 1 atmosphere) ■ Diynbutyl carbinol...176°~
184℃ (boiling point under 1 atmosphere) ■Normal off-tyl alcohol ・・・・・・193
° to 196°C (boiling point under 1 atmosphere). Among these, n-probeer alcohol, inbutyl alcohol, etc., which have low boiling points, should be used immediately after manufacturing the plastic/commutator or when assembling the motor.

It is even more effective if it is adsorbed into the commutator's blood.

The monoalcohols mentioned above are adsorbed onto the surfaces of the brushes and brushes to form a monomolecular film, which greatly improves lubricity and significantly reduces wear on the contact parts. (The results of the experiment are shown in Fig. 6.) In Fig. 6, A and B show rectification waveforms in a styrene monomer atmosphere containing unsaturated cyclic hydrocarbons, and A shows rectification waveforms at 60°C and 6%RH. B is the rectified waveform before the test, and B is the rectified waveform after the 100-hour test at 60°C and 5th gear. In addition, C and D show the confirmation results when approximately 10 μq of hydrocarbon (toluene) was adsorbed on the surface of the comm data segment. This is a rectified waveform after a %RH 300 hour test.

Furthermore, E and F show the confirmation results of the monoalcohol according to the present invention in an ambient atmosphere, E is the rectified waveform before the test at 60°C and 6% RH, and F is the rectified waveform after the 1500-hour test at 60°C and 6% RH. It is a waveform.

Effects of the Invention As is clear from the above description, the present invention provides the following effects.

■ By adsorbing monoalcohols to the surfaces of commutators, segments, and brushes, a lubricating effect works, which has the effect of preventing abnormal wear and abrasion damage on sliding parts.

■ Even if there is an organic gas with a benzene ring such as styrene monomer or toluene, it will be protected by a film of monoalcohols that is adsorbed on the brush and commutator segment surfaces, and the formation of blackened substances will be minimal. It can prevent poor contact between the two. In addition, since contact failure does not occur, the generation of electrical noise is reduced, and the speed of small motors that is caused by unstable contact is stabilized, resulting in less wow and flutter in equipment that uses small motors. This has the effect of reducing

Ci) A11Be(f)ゎOo! '! ,"tJ'-
fly==p. AJty>E'/ can be improved and the life can be significantly extended.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram of a conventional example, FIGS. 2a to 2C are diagrams showing the configuration of a commutator sliding part of a conventional example, and FIGS. 3 and 4 are configuration diagrams of an embodiment of the present invention, respectively. Figures 5a and 5b are longitudinal and cross-sectional views of a small motor according to still another embodiment of the present invention, and Figure 6A is a diagram that does not show the rectified waveforms of the conventional example and the present invention. be. 3... Commutator sliding part, 4... Commutator segment, 12... Bracket, 13... Housing, 14... Monoalcohol Felt impregnated with similar substances. Figure 1 Figure 2 (α) (Figure 3 1 Figure 5rR

Claims (1)

[Claims] A small motor that has a brush mechanism and a commutator, and the brush and the commutator slide in contact with each other, has a linear carbon bond in the motor case, or has a side chain, and has more H groups in its molecular structure. A small motor with the atmosphere of a monoalcohol.