JPS59173584A - Rotary pump and its rotor for oil pump lubricating internal-combustion engine - 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]

The present invention relates to a rotary pump for an internal combustion engine lubricating oil pump using a rotary pump utilizing a trochoidal curve, and its rotor. Traditionally, rotary pumps using trochoidal curves

[The inner rotor has a basic diameter of A, as shown in Figure 1.
When the diameter of the rolling circle is B1, the eccentricity is e, and the trajectory circle diameter is C, the rolling circle rolls on the base circle without slipping, and the trajectory is drawn by a fixed point within the rolling circle that is separated by e from the center of the rolling circle. The trochoidal curve T7<ii is obtained as follows, and the tooth-shaped curve TC is obtained as the envelope of a group of circular arcs having a diameter φC that passes to the right of the center on the trochoidal curve T. The curve of the outer rotor is mainly composed of (n+1) circular arcs with a diameter C and whose center is on the circumference of a circle with a diameter A and B. FIG. 2 shows the relationship between the inner rotor 1 and the outer rotor 2. Normally, the inner rotor 1 is fixed to the drive shaft 3 with a key as shown at 5 and rotates. The outer rotor 2 is housed in a case eccentric by e with respect to the drive shaft 3, and rotates as the inner rotor 1 rotates. The volume of the space 4 between the inner rotor 1 and the outer rotor 2 changes during rotation, thereby causing suction and discharge of fluid. The combination gap 2 between the curve of the inner rotor 1 and the curve of the outer rotor 2 obtained from the above-mentioned specifications using the trochoid curve is O, and since it is in a non-rotatable state, the inner rotor actually Either make the curve 1 smaller or greatly modify the curve 2 of the outer rotor.
A combination gap of 2 m is created that allows C rotation. However, in this repair method, the curve has been modified empirically in the past, and the combination gap 2 of each part in a commercially available pump that uses a trochoid curve is not constant, and it depends on the change in the rotation angle θ shown in Fig. 2. Accordingly, it fluctuates as shown by the solid line in FIG. 3, and if the rate of fluctuation is S, then it is approximately 60 to 80%. The volumetric efficiency of the pump can be improved by reducing the maximum combination gap gmax, but in the case shown in Figure 3, if the combination gap is reduced, the minimum combination gap as shown in part a of Figure 3 At the alignment gap > min portion, tooth interference occurs, resulting in poor rotation. That is, the limit to which the combination gap can be made smaller depends on the combination gap fluctuation rate S. In this way, the gap variation rate S between the inner rotor 1 and outer rotor 2 in a conventional rotary pump is 60 to 80%.
Therefore, the maximum gap cannot be reduced by 1, so
Volumetric efficiency is poor under high-temperature conditions and low-speed conditions, and even if this gap variation rate is to be corrected, manual correction is required by trial and error.
The drawback was that it required a lot of time and money to manufacture. The present inventor has searched for a condition in which the gap variation rate between the inner rotor and the outer rotor of a rotary pump using the above-mentioned trochoid curve is reduced to 1 for every 1 - 1, and as a result, the present invention has been arrived at. It is. This invention will be explained below based on FIG. That is, this invention uses a rotary pump that utilizes a trochoid curve as an oil pump for lubricating an internal combustion engine. (1) Among the trochoid specifications, the basic circle diameter is A mm, the z-circle diameter is B mm, and the center suspension is e.
mm, eccentricity fe=e/B, base circle ratio n=Az'
When B, fe is o<re≦ fe(n) in 1 orbit λ, λ4 fe (n) = a, + −+−−+−+7 generation
6] Horsefly (however, part a, a,, a,, a,, a4 is a,
= 0.5, a, -= , 1.434, a knee-1
The constants are 9,79, a, -51,02, a4--33.11. ) Select the trochoid specifications so that (n) the center of the arc surface of the outer rotor and the outer [
When the correction value of the center distance from the center of the 1-tar is △b mm, and the correction iE value of the arc radius is 8 Caya, I△b 1
Select △b and △C so that +1△C1〈0.3mn1 (where △b〉△C) and modify the outer [1-ter curve, so that it has a curve shape that satisfies The present invention provides a rotary pump rotor, which is used as an oil pump for lubricating an internal combustion engine, and is characterized in that the fluctuation rate of the matching gap between the inner rotor and the outer rotor can be reduced to 0 to 60%. In this invention, the eccentricity fe that satisfies the condition (1) of claim 2 differs depending on the value of the basic circle ratio 0-△/B. By checking the eccentricity f for the value of n
e was calculated. The result is the formula % formula % () a4=-33, a constant of 11. ). If the eccentricity [e] is selected within the above range, the combined gap variation rate S can be set to 0 to 60%, and as n increases, the selection range of the eccentricity [e becomes wider; The gap variation rate S also becomes smaller. In this invention, n in the above formula is the basic circle diameter A mm
Since the ratio of the rotation diameter B mm and the base circle ratio A/B is set, n is an integer such as 1.2.3... as in the case where the number of teeth of a conventional inner rotor is 11. The eccentricity of the case is (n=4.5, n=5.
This can also be applied to cases with special tooth profiles such as No. 5. Next, as for the modification of the outer rotor curve in Claim 2, referring to the explanatory diagram showing the modification elements of the outer rotor curve in FIG. Correction value of arc surface radius (02mm
-〇+mm) is △c mm, and the correction value of the arc center distance (002mm - surface 1mm) is △bn1m. Conventionally, △b = +0.2~0.4mm (+ means the center distance is large) direction), △C=-+0.1~0.3mm (+
The culmness is corrected (in the direction in which the arc radius is straight), and when the horizontal axis is the rotation angle θ of the inner rotor 1 of these commercially available bongs 1 and the vertical axis is the gap tooth, the curve is Third
As shown in the figure, if the maximum gap 'i+ max is made small as indicated by the dotted line, tooth interference will occur at point a of p min, so there is a limit to making the maximum gap small. In this invention, as a result of analyzing this correction value by theoretical calculation of the combined gap and Ni verification of the actual product, >max, fang miλ, and combination gap fluctuation rate S when trochoid specifications are given, arc center distance A function of the correction value △b and the correction value △C of the arc radius, that is, >max = f+
(Δb1△C) smin = (p (△b1△C
)S=f, (Δb1△c), and for the desired g max, △b and △0
By selecting the respective correction values Δb and ΔC so that the sum of the absolute values of is 0.3 mm or less, the gap fluctuation rate S is also smaller than that of conventional commercially available pump rotors (60% or less),
The undulations of the gap change curve become smooth as shown in the gap change curve when the outer rotor curve is corrected in Figure 3, so even if the maximum gap 't max is set small, rotational failure will not occur. It is. As described above, the present invention achieves a gap variation rate of 0%, whereas conventional commercially available rotors have a gap variation rate of 60% to 80%, due to the conditions (+) and (n) described in claim 2.
The amount of oil leakage can be reduced by ~60%. For example, if we compare the case where the variation rate is 80% and the case where the variation rate is 20%, in the latter case, even if the maximum gap C is reduced to 1/4 of the former case, rotational failure will not occur. And for example maximum gap 0
, 2 mm and 0.5 man, there is a maximum difference of nearly 40% in volumetric efficiency under high temperature or low speed conditions. In this way, the gap is kept almost constant over the entire circumference,
And by making it smaller, the performance of the pump, especially high F,
Under one condition, the volumetric efficiency under low viscosity fluid usage conditions 1' and low speed operating conditions can be significantly improved. Also, according to this invention, since the product and the desired value can be expressed mathematically accurately, the analysis bar 4 calculation can be done in a short time, which also has the effect of making it possible to design the shape and manufacture it in a short time. . Thus, (1) in the A-il pump for internal combustion engine lubrication, due to the nature of lubricating the screws 1 to 1 and the cylinder,
The oil becomes hot, its viscosity decreases, and the influence of gaps on volumetric efficiency becomes greater, and the use of the rotor of the present invention is highly effective even under such usage conditions. (2) Depending on the environment in which the oil pump is used to lubricate an internal combustion engine, the temperature will be quite low, especially when starting up, and the speed will be low when idling. The uniform-gap rotor of the invention has less torque fluctuation, and at low speeds, high volumetric efficiency can be obtained not only for low-temperature oil but also for high-temperature oil.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram of trochoid curve specifications, Fig. 2 is an explanatory diagram of a combination gap between an outer rotor and an inner rotor using a trochoid curve, and Fig. 3 is a gap variation curve of a commercially available oil pump rotor. FIG. 4 is an explanatory diagram showing correction elements for the outer rotor curve in the present invention. A...Base circle diameter B...Rotated circle diameter e...Eccentricity 1...Imboo rotor 2...Outer rotor 3...Drive shaft 4...Gap portion 5...Key 0
...Center of the outer rotor of the trochoid theoretical curve 01...Same arc tooth center C1...Same arc tooth radius 02...Modified arc tooth center C2...Modified arc inner radius agent Person Patent Attorney Kazu 1) Showa 3rd
Figure 2 Figure 4 Procedure...JEp issue (voluntary) 1. Display of the case 1982 Patent Application No. 49289 2, Title of the invention Rotary pump for internal combustion engine lubricating oil pump and its date -
Third, what is the relationship between the person making the amendment and the patent applicant?
Address: 5-15 Kitahama, Higashi-ku, Osaka 1jL, -1;
-□ Name (213) Sumitomo Electric Industries, Ltd. 4, Agent address Wakasugi Building, 1-18-18 Nakatsu, Oyodo-ku, Osaka City

Claims (1)

[Scope of Claims] (1) A rotary pump for an internal combustion engine lubricating oil pump, characterized in that a rotary pump utilizing a trochoid curve is used as a self-destructing engine lubricating oil pump. (2) In a rotary pump that uses a trochoid curve, so that the combined gap between the inner rotor and outer rotor is almost constant over the entire circumference, (1) Among the trochoid specifications, the base circle diameter is A mm,
The radius of rotation is B mm, the amount of eccentricity is e mm, and the eccentricity fe=
e/[3, base yen ratio n= A/B thud,
fe is Q < fe≦fe(n) re (n) 7ab-+-u +-E> +-4
281 η Irl″mゝ use now (however, ao,
a,, a! , a,, a4 is a, -0,5, a,
= 1,434,a, = -19,79,a, =
51.02, a4=-33, a constant of 11. ) Select the trochoid specifications so that (ii) the correction value of the center distance between the center of the arc tooth of the outer rotor and the center of the outer rotor is △b mnl,
When the correction value of the arc radius is △c mm, l△b
l+l△Cl < 0.3mm (However, △l) >Δ
C) A rotor for a rotary pump for an internal combustion engine lubricating oil pump, characterized in that the outer rotor curve is modified by selecting Δb1ΔO so that it has a curve shape that satisfies the following.