JPS60256581A - Rotary scroll type fluid machine - Google Patents

Abstract

PURPOSE:To keep off any damage to a scroll body due to machining and assembling errors, by making up the scroll body, revolving in a revolution radius rho, with an outer curve consisting of an involute curve and an inner curve of a radius R, while connecting both these curves so smoothly. CONSTITUTION:In this scroll compressor, substntially identical scroll bodies are combined in one as being dislocated by 19 deg. each, and its operation takes place with one side scroll body revolved in a radius p to the other. An outer curve of the scroll body consists of an involute curve, while an inner curve is made up of a circular arc of a radius R. And, both these curves are smoothly connected with a curve having a circular arc of a radius r. In this connection, these radius R and r are determined as in an expression shown in illustration when (b) is set down to a base radius of the involute curve.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a rotary fluid machine.

[Conventional technology]

For example, in a known crawl type compressor, one of two spiral bodies having the same shape, as shown in FIG.
is fixed to a seal end plate having a discharge port 4 approximately in the middle, and both are rotated by 18σ relative to each other, and the 5-wheel bodies of both are connected to each other at four points 51, 52, 51', and 52'. They are stacked on top of each other with a relative shift of a distance of 2ρ (= spiral pitch - 2 × spiral plate thickness) so that they are in contact, one spiral body 2 is stationary, and the other spiral body 1 is set at a crank radius of ρ. With the crank mechanism, one of the spiral bodies 2 rotates around the center O (radius ρ
= 00', it is configured to make a revolution.

Then, between the two spiral bodies 100, there are points 51 and 52 where both the spiral bodies abut, and points 51' and 52'.
A sealed small chamber 3, 3 is formed between the sealed small chambers 3, 3.
The volume of the spiral body 1 gradually changes as the spiral body 1 revolves.

That is, from the state of (1) in the same figure, first turn the spiral body 1 into 9
When it revolves at 0 degrees, it becomes (2) in the same figure, when it revolves at 180 degrees, it becomes (3) in the same figure, and when it revolves at 270 degrees, it becomes (4) in the same figure.
During this period, the volume of chamber 3 gradually decreases, and in figure (4), the two chambers 3°3 communicate with each other to form chamber 53, and when it revolves another 90 degrees from the state of figure (4), it becomes the same. Figure (1) is obtained, and the volume of the small chamber 53 is calculated from Figure (2) to Figure (1).
3), and the volume becomes the smallest between (3) and (4) in the same figure, and during this time, the outer space that began to open in (2) in the same figure increases in (3) and (4) in the same figure. Figures (4) to (1)
Then, new gas is taken in to form a sealed small chamber, and this process is repeated thereafter, and the gas taken in from the spiral body outer space is compressed and discharged from the discharge port 4.

The above is the operating principle of a scroll type compressor. Specifically, as shown in the vertical cross-sectional view of FIG.
Rear end plate 12. Consisting of a cylinder plate 13, an intake port 14 and a discharge port 15 on the rear end plate 12.
When the spiral body 252 and the disc 25 are protruded, the spiral body 252 and the disc 25
The stationary scroll member 25 consisting of 1 is fixed, and the front two
The main shaft 17 is pivotally connected to the crank pin 23, and a radial needle bearing 26. Boss 243 of the revolving scroll member 24. Square tube member 271. A revolving scroll member 24 comprising a spiral body 242 and a disc 241 is attached via a revolving mechanism comprising a sliding member 291, an IJing member 2929, a rotation stopper 293, and the like.

The shape of the spiral bodies 1 and 2 of such a scroll type compressor is determined by, for example, the outside of the spiral body, as described in detail in Japanese Patent Application No. 1976-1972 proposed by the present inventors. And most of the inner curve can be composed of involute functions, but as described in the operating principle, the small chamber 53 gradually decreases its volume, and as a result, high-pressure fluid is discharged from the discharge port. When the spiral body has a thickness, the volume of the small chamber does not become zero, and there is a phenomenon in which a so-called top clearance volume remains.

In other words, as shown in the enlarged view of the main part in Figure 8, (1)
corresponds to Fig. 5 (3), two spiral bodies 1,202
The small chamber 53 formed between the two contact points 52 and 52' is
If it revolves further, it will look like the same figure (2), and at this point, small room 5 will be created.
The volume of the spiral body 3 becomes the minimum, and when the spiral body 1 is further revolved, the two spiral bodies 1 and 2 are separated, and the contact point is 52°52
' has disappeared, and the small chamber 53 formed between the two spiral bodies 100 communicates with the small chamber 3.3 formed on the outside of each spiral body.

Therefore, the high-pressure fluid in the minimum volume of the small chamber shown in FIG. The compressor's work done on the compressor becomes N loss.

In addition, since each of the tips of the center portion of the spiral body 1.2 has a sharp edge, these portions may be damaged during operation, and furthermore, machining of these tips requires a lot of man-hours.

In order to solve this problem, the present inventors previously proposed a rotary fluid machine equipped with a spiral body as shown in the 9th front view in Japanese Patent Application No. 57-206088.

That is, in the same figure, 501 is a fixed side spiral body,
601 and 602 are the outer and inner curves of the spiral body 501, respectively, the outer curve 601 is the base circle radius, the involute curve of the starting point A, and the phase between the EF of the inner curve 602 and the outer curve 60] is the angle π-F. The shifted involute curve, DB is a circular arc with radius R, and the outer curve is 60
1 and the inner curve 602 has a radius r
Point A is the involute starting point of the outer curve 601, Point B is the boundary point between the outer curve 601 and the connecting curve 603, and the tangents of both curves are equal at this point.Point C
is a point sufficiently outside the outward direction a601, and the point is the inner curve 60
2 and the connecting curved line,. 3. ) Boundary point a1. radius R and 4. ) The two arcs touch, point E is the boundary point between the inner curve 6020 arc (between DB) and the involute curve EF, where both curves make their tangents equal, point F is well outside the inner curve 602 This is the point.

The same applies to the other revolution side spiral body 502.

In this case, the radius R9r is expressed by the following formula.

R=ρ+bβ10d・・・・・・・・・・・・・・・
・・・・・・・・・ (1) r = bβ0d ・・・・
・・・・・・・・・・・・・・・・・・・・・・・・
・ (2) Tag, ρ: Radius of revolution b = base circle radius ρ −b”−(−4bβ)2 d=−−−−−−−… (3) 2(−10bβ) β= It is a parameter.

'' 5, I-11 (ttWA OtjA; 6a''!
&jlj17) , is in contact with the base circle at the above intersection point.

Next, in FIG. 10, 502 is a spiral body on the revolution side;
552 and 552' are contact points of both spiral bodies, respectively;
553 is a small chamber formed at contact points 552° and 552';
503 and 503 are the outer chambers, and (1) in the same figure is
Figure 8 (1) and Figure 8 (2) correspond to Figure 8 (2), respectively, and Figure 8 (3), (4), and (5).
2 shows the case where the spiral body 502 is further revolved from FIG. 2 (2).

In this proposal, both spiral bodies 501 and 502 are relatively
, When the revolution is performed in the order of (5), the contact point 552 ,
The volume of the /J% chamber 553 formed at 552' decreases,
In the same figure (5), contact points 552 and 552' are the same point,
.

As a result, the volume of the small chamber 553 becomes zero.

For this reason, the top clearance volume that would normally exist becomes zero, so all of the fluid compressed from this volume is discharged to the outside from the discharge port (not shown), and all of the work that the compressor does to the fluid is The losses imparted to the fluid that previously existed are eliminated.

In the above embodiment, the size of the discharge port has been ignored for convenience of explanation, but in reality, it is necessary to form the discharge port at an appropriate position where the small chamber 553 is formed, so this allows for some top clearance. Although a volume is generated, this amount is much smaller than in the conventional case and can be considered as substantially zero.

As shown in FIG. 9, the tips of the central portions of the spiral bodies 501 and 502 are formed into circular arc connecting curves 603, thereby eliminating sharp edges and preventing damage to these parts during operation of the machine. Also, the inner curve 60
By making the two DEs and the connection curve 603 circular arcs, the spiral body can be easily processed.

According to the above proposal, great effects can be obtained, but
On the other hand, the following inconveniences may occur.

In other words, if a certain degree of machining error occurs in both spiral bodies, or if the relative positional relationship of both spiral bodies is not properly assembled, abnormal force will be generated in both spiral bodies, and, for example, if the scroll type In the case of a compressor, especially during high load operation where there is a large difference between the low pressure side pressure and the high pressure side pressure,
The above-mentioned abnormal force becomes even thicker (as a result, the rigidity near the arc of radius r at the tip of the spiral body in FIG. 9 is relatively small, and this portion may be damaged.

In addition, in machines designed so that both spiral bodies are in contact, the relative sliding rate of both spiral bodies at the inner part is much greater than that at the outer part, so the spiral body wears out at the inner part. The inside of the device will be filled with it, causing inconvenience.

, . Spiral body “゛ Non-tangent! L! L is 6 J
7. Even in a well-developed machine, if there is a certain degree of machining error in the spiral body or if both spiral bodies are not assembled correctly, wear will occur in this area and similar problems will occur.

The present invention has been proposed in view of these circumstances, and provides a high-performance rotary fluid machine that prevents the spiral body from being damaged or abnormally worn even when there are machining errors or assembly errors. The purpose is to

[Means for solving problems]

For this purpose, the present invention rotates the stationary side spiral body and the revolving side spiral body, which are spiral bodies of substantially the same shape, by 180 degrees, so that the revolution side spiral body revolves with a revolution radius ρ relative to the stationary side spiral body. In this case, each of the spiral bodies has an outer curve made of an involute curve, an inner curve made of an involute curve having an arc of radius R inward, and the outer curve and the arc of radius R are smoothly connected. Both spiral bodies have a circular arc with a radius r that By providing a very small gap between the bβ) b: base circle radius of the involito curve).

[Effect]

With such a configuration, a rotary fluid machine with long life and high performance can be obtained.

〔Example〕

One embodiment of the present invention will be explained with reference to the drawings. Fig. 1 is a front view showing the spiral body, Fig. 2, Fig. 3, and Fig. 4.
Each figure is a front view showing a modification of FIG. 1.

In the above figure, the same reference numerals as in FIG. 9 indicate the same members and dimensions as in the same figure. First, in FIG. It is an inner curve.

The outer curve 711 is an involute curve from the base circle radius to the starting point, the inner curve 712 between EF is an involute curve whose phase is shifted from the outer curve 711 by an angle π - foot, and the radius between EI is Rc, which is the same as the diameter of the end mill cutter. The arc of I
The distance between G is a circular arc with a center radius of approximately 030, and the connecting curve 713 connecting the outer curve 711 and the inner curve 712 is a circular arc with a radius r.

Here, the EIG of the inner curve 712 is constructed by retracting the gap △C so that it is slightly closer to the outer curve 711 than the inner curve 602 in FIG. 9, and for convenience of explanation, the gap △C
is shown in a large size, but in reality it is a small amount.

Point B is a boundary point between the outer curve 711 and the connecting curve 713, and the tangent lines thereof are made equal, and an involute curve is formed outside the point B (on the C side), and an arc is formed inside the point B (on the G side).

Point A is the involute starting point of the outer curve 711, point C is an arbitrary point sufficiently outside the outer curve 711, and point F is the inner curve 71.
Point G, which is an arbitrary point sufficiently outside of 2, is the intersection of the circular arc of the radius of the inner curve 712 and the connecting curve 713, and on the circular arc of radius r
Provided at any position between B.

The spiral body on the revolution side has a similar configuration.

With this N, R = ρ + bβ + dr = bβ + d ρ: Radius of revolution b = Radius of the base circle b2 - (-1 - bβ) 2 d = - ρ 2 (-10 bβ) β: Parameter (represents the range in which the involute is realized) (see Figure 1), a straight line passes through the origin O and forms an angle β with the X-axis, and a straight line EO,, BO.

The straight lines are perpendicular to each other, and EO and BO are parallel.

The difference between this embodiment and the one in FIG. 9 is that the inner curve 712
Both the configuration of 0EIG and the length of BG of connection curve 713 exist, and the broken line in FIG. 1 indicates the corresponding portion in FIG. 9.

In such a spiral body, when both spiral bodies are engaged, a point F on an arbitrary involute curve sufficiently outside the inner curve of the fixed side spiral body 701 and the corresponding revolution side spiral body (not shown) The involute corresponding points of the outer curves of
01 on the inner curve 712 and the corresponding point on the outer curve of the revolving side spiral body (this is the fixed side spiral body 7010
When the two spiral bodies contact each other up to the same point as point B) and continue to revolve from this point, both spiral bodies will form curve 6. , o2. , Q'' and the EIG of curve 712 are operated with a gap ΔC between them.

Therefore, the contact between the two spiral bodies at the inner part occurs up to point E (contact with point B of the other spiral body), and from this point onwards △C
Since there is only a slight gap, the following effects can be achieved.

(1) Even if there is a certain degree of machining error in the whirlpool body, or even if both whirlpool bodies are not assembled correctly, the vicinity of the inner tip of the whirlpool body will not come into abnormal contact with each other during high-load operation. In particular, damage to the arcuate portion of radius r, which has relatively low rigidity, is prevented.

(2) Moreover, since there is no longer any abnormal abutment at the inner part, the inconvenience of abnormal wear of the spiral bodies at the inner part where the relative slip rate of both spiral bodies is high is eliminated.

(3) Since the clearance △C is small, the patent application No. 1983. −
The idea of No. 206088 can be substantially realized without loss and it is possible to provide a machine with good efficiency.

(4) In machining a spiral body, the radius Rc between EI is the same as the diameter of the end mill cutter, and the radius Rc between IQ is approximately the same, so that machining can be performed very smoothly.

The intention of the present invention is as follows: Patent Application No. 57-206088
In the configuration of No. 1, when the inner curve 712 (602) and the connection curve 713 (603) between the involute establishment limit point JB determined by the parameter β are combined, the operation is performed with a slight clearance between EB. The reason for this is that the spiral body is constructed so that the shape of the spiral body can be modified as shown below.

(1) The radius between the arcs 81 in FIG.
Any curve having a radius of curvature greater than or equal to the radius of the end mill canter is acceptable as long as it is equal to or greater than R given by the formula.

In short, the gap ΔC may be provided so that the inner curve is slightly closer to the outer curve than between EB in FIG.

(2) If necessary, the entire gap between EB in Figure 9 is △C.
Instead of providing a gap ΔC, a gap ΔC may be provided only in an arbitrary part between EB, as shown in FIG.

In this roof tile, 802 is a spiral shape, H is a point on the inner curve, HE is a circular arc with a radius of about 1,000 yen, and HG is an inner curve that is drawn into the outer curve by a slight gap △C than 602 in Fig. 9. , and β is smaller than the parameter β
A gap ΔC is provided between the inner curve 602 in FIG. 9 and the H point corresponding to '.

(3) Providing a clearance ΔC on the inner curve 9 Alternatively, as shown in FIG. 3, a clearance ΔC may be provided on the connecting curve.

In this roof tile, 913 is a connection curve formed by retracting △, C from the connection curve 603 in Fig. 9 with a slight gap, and is located inside from the point of contact between the connection curve 603 and the inner curve 602 in Fig. 9. The configuration is such that an intersection J with the inner curve 602 is provided on the curve side (point E side).

(4) As shown in Figure 4, the shape of either the fixed side spiral body or the revolving side spiral body is the same as in Figure 9, and only the other spiral body has a clearance in both the inner curve and the connecting curve. It may be configured to provide ΔC.

Here, 几 and r are configured to become Dr)R and r'<r, respectively.

912 is the inner curve, 914 is the connecting curve, and the point is the connecting point of 912 and 914.
Provide a slight gap between both curves.

Good, good luck! :, 4 @ 4' (F. Uga 1□
In this case, if R'-r'=ρ, the intersection of R' and r' will be in contact, resulting in a smooth curve.

In (3) and (4) above, the curvature of the arc at the center tip of the spiral body is slightly smaller than in the specific example, and the rigidity is reduced by this amount, but the gap is very small, so
There is virtually no effect.

(5) The present invention is of course applicable to pumps, expanders, etc. in addition to compressors.

〔Effect of the invention〕

In short, according to the present invention, the stationary side spiral body and the revolving side spiral body are made of spiral bodies having substantially the same shape, and are rotated by 180° so that the revolution side spiral body revolves with the revolution radius ρ with respect to the stationary side spiral body. In such a structure, each of the spiral bodies has an outer curve made of an involute curve, an inner curve made of an involute curve having an arc with a radius of about 100 mm inside, and the outer curve and the arc of the above radius of about 100 lbs. When formed with a connecting curve having a connecting arc of radius r, both spirals are formed so that the inner curve between the involute curve establishment limit points determined by the parameter β and a part or all of the connecting curve are separated from contact. By providing a very small gap between the bodies (by adding R = ρ + b β d r = b β + d b' - (- + b β)' d = = □ 2 (~10 β) b: of the involute curve The present invention is industrially extremely useful because a rotary fluid machine with a long life and high performance can be obtained due to the radius of the base circle).

[Brief explanation of drawings]

FIG. 1 is a front view showing a spiral body according to an embodiment of the present invention;
2, 3, and 4 are front views showing modified examples of FIG. 1, FIG. 5 is a diagram of the operating principle of a known scroll compressor, and FIG. 6 is a diagram of a known scroll compressor. Fig. 7 is a cross-sectional view taken from ■-■ in Fig. 6;
The figure is a partially enlarged cross-sectional view showing changes in the relative position of the spiral body in Figure 6, Figure 9 is a front view showing the spiral body proposed in Japanese Patent Application No. 57-206088, and Figure 1O is the 9th spiral body. FIG. 3 is a partially enlarged cross-sectional view showing changes in the relative position of both spiral bodies of the scroll compressor equipped with the spiral bodies shown in the figure. 602...Inner curve, 603...Outer curve, 701
...Spiral body, 711...Outside curve, 712...
・Inner curve, 71'3... Connecting curve, 802... 2. Spiral body, 812... Inner curve, 912... Inner curve, 913... Connecting curve, 914... Connecting curve, b. ...Base circle radius of involute curve, △C...Gap, R, R, 't r...Radius, Kai β, β4...
Parameter, ρ...Revolution radius. Sub-Agent Patent Attorney Masa Tsukamoto Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 (1) (2) Figure 6 0 Figure 7 Figure 8 (1) (,2) Figure q

Claims (1)

[Scope of Claims] The stationary side spiral body and the revolving side spiral body, each consisting of a spiral body having substantially the same shape, are rotated by 180° and meshed with each other, so that the revolution side spiral body has a revolution radius ρ with respect to the stationary side spiral body. In the one that revolves, both spiral bodies are each formed by an outer curve consisting of an involute curve,
An inner curve formed by an involute curve having an arc of the radius hole inward, and a connecting curve having an arc of radius r that smoothly connects the outer curve and the arc of the radius hole; A very small gap was provided between both spiral bodies so that the inner curve and the connecting curve between the involute curve formation limit points determined by β are partially or completely in contact (Tag, R = ρ + b β A rotary fluid machine characterized by the following: d r = b β + d ρ b'-(-+b β)'' b = base circle radius of an involute curve).