JPS60162088A - Rotor driving apparatus for single-shaft eccentric screw pump - Google Patents

Abstract

PURPOSE:To improve the capacity of a pump by rotatably supporting an eccentric rotor shaft in eccentricity by a certain amount from the revolution axis line of a crank drum onto said crank drum having the revolution axis line concentric to a stator axis line and smoothing the revolution of the eccentric rotor. CONSTITUTION:A crank drum is rotatably supported onto a bearing 13 installed in the lower part of a bearing housing 12, allowing the revolution axis line 11l to coincide with the extension line of the axis line 2l of a stator 2. An eccentric rotor shaft 5 is connected to the crank drum integrally rotatably through a keyless joint 15. The crank shaft 14 which constitutes a part of the eccentric rotor shaft 5 is rotatably supported through a bearing 16 at the position in eccentricity by a prescribed amount from the revolution axis line 11l of the crank drum, and turns a driving shaft 26. Therefore, a rotor can be driven by revolving the crank drum 11.

Description

Detailed Description of the Invention (Industrial Application Field) This defense is based on the fact that the internal threaded hole formed in the stator is formed as an inner surface with an oval cross-section in the engaging part for the Hl threaded rotor, and This invention relates to a rotor drive device in a uniaxial eccentric screw pump having a structure in which a male screw rotor engages and rotates around an eccentric rotor shaft.

(Prior art) This pump has a four-stage structure, and since the Ht screw rotor rotates eccentrically, the rotor cannot be directly connected to the drive shaft of the drive device and rotated. As shown in the figure, the rotor 4 and the drive shaft 26 were connected via a universal joint 60.
The figure shows an example of a conventional structure. For this reason, the overall length of the pump becomes extremely long, making it inconvenient to handle.Also, when the rotor 4 rotates, its movement is restricted only by engagement with the wall of the female threaded hole 3 of the stator 2, and the pumping action is performed. 4 rotation is unstable and vibration becomes large,
The inner wall surface of the female threaded hole 3 of the stator 2 was fatigued, and the straight parts were particularly prone to wear, and the stator 2 had to be replaced frequently. In particular, the pump shown in Fig. 1 has two universal joints 60 on both sides of the intermediate shaft 61 to connect the rotor 4 and the drive shaft 32 in order to make the rotation of the rotor 4 smooth. In this case, only the rotational force is transmitted to the rotor 4, and its movement is not regulated in any way by the drive device, so the above-mentioned drawbacks could not be solved.

In addition, in conventional fS construction, the universal reel joint 60 is generally placed near the female screw hole 3 of the stator 2, which increases flow path resistance and reduces pump performance. Risk of long inflow material becoming entangled (objective of the invention) This invention has been made in view of the above points, and is designed to prevent a male-threaded rotor from rotating around an eccentric rotor shaft within a female-threaded hole of a stator. In a uniaxial eccentric pump in which a female screw hole is formed so that the eccentric rotor shaft rotates (revolutions) while maintaining a constant eccentricity m from the stator axis, the eccentric rotor shaft has a rotation axis on an extension of the stator axis and is rotatable. The eccentric rotor shaft is rotatably supported by a crank drum disposed at a position eccentric from the rotation axis of the drum to a position equal to the eccentricity m of the eccentric rotor shaft, and the rotation of the drive shaft is transmitted through a rotation transmission mechanism. By rotating the rotor with the rotor shaft, the overall length is significantly shortened compared to conventional pumps, and the eccentricity is transmitted to the drum. This reduces wear on the wall of the female screw hole in the stator, maintains high pumping capacity over a long period of time, and compared to the conventional rotor drive device using a universal joint.
It is an object of the present invention to provide a rotor drive device that reduces flow path resistance from a suction port to a pump device and improves pumping performance.

(Structure of the Invention) This invention achieves the above-mentioned object by forming the tinted screw hole formed in the stator as an inner surface with an oval cross section on the engagement surface for the male screw rotor, and Eccentricity e ('J) In a uniaxial eccentric screw pump that engages and rotates around an eccentric rotor shaft, a crank drum is rotatably disposed with its rotational axis aligned with an extension of the stator axis, and the crank The eccentric rotor shaft of the rotor is rotatably supported by the drum, and the support center position is eccentric from the rotational axis of the crank drum by the eccentric amount e.
A small gear having a gear diameter twice that of the eccentric amount e is provided at the rear end of the eccentric rotor shaft, the small gear is fixed adjacent to the rear end of the crank drum, and has a gear diameter four times the eccentricity e. The rotor drive is characterized in that the outer ring gear is internally meshed with the outer ring large gear, and the rotation of the drive shaft of the drive device is transmitted to the crank drum via a rotation transmission mechanism so that the rotor is rotated by the eccentric rotor shaft. This paper focuses on 8 devices.

(Example) Embodiments of the present invention will be described below with reference to the drawings.

In Figures 2 to 7, Figure 2 shows the overall view of the uniaxial eccentric screw pump, with pump device △, suction part B, outlet 1 outlet C
, jle and rotor drive device.

The structure of the pump device is similar to that of conventional pumps, with a stator 2 fixed inside a cylindrical stator housing 1.
The male threaded rotor 4 is rotatably engaged with the female threaded hole 3 formed in the stator 2! 11); It is inserted,
Further, an eccentric rotor shaft 5 is integrally provided on the end surface of the male threaded rotor 4 on the side of the suction portion B, eccentrically eccentric by an eccentricity me from the cross-sectional center 4o of the rotor 4.

The male threaded rotor 4 is formed from a single thread with a circular cross-section, while the female threaded hole 3 of the stealer 2 has an oval cross-sectional shape consisting of a straight line connecting the opposing half-inner portion and the opposite half-inner portion. The diameter d of the inner half is equal to the diameter d' of the circular cross section of the rotor 4 (strictly speaking, d>d'), and as shown in FIG. In addition to the length of the straight line, the distance between the center points X and Y of the opposing half halves is set to 4C, which is 4 times the 1-center (ice) of the eccentric rotor shaft 5 with respect to the cross-sectional center 4o of the rotor 4. , the bit of the fine screw hole 3 may be made larger than [1-ter 4, but here it is set to 2-8. In each cross section of the stator 2, a female screw hole 3 and a male screw rotor 4 are provided.
represents the positional relationship with Incidentally, since the female threaded hole 3 and the male threaded rotor 4 are set in the above relationship in cross section, when the eccentric rotor shaft 5 is rotated once in one direction, as shown in FIGS. 6(a) to (d), The rotor 4 rotates once in the opposite direction while engaging with the wall of the female threaded hole 3, and the cross-sectional center 4o of the rotor 4 reciprocates in a straight line between X and Y in FIG. 5 cross-sectional center 5o
The locus of movement draws a circle with the eccentricity C as the radius centered on the cross-sectional center 3oq of the female threaded hole 3, or in other words, the axis 2o of the stator 2.

Next, to explain the structure of the rotor drive device, the crank drum 11 is installed in the lower part of the bearing housing 12 with the rotational axis 11 aligned with the extension of the axis 2 of the stator 2. The keyless joint 1 is rotatably supported by the eccentric rotor shaft 5 and rotatable integrally with the eccentric rotor shaft 5.
The crankshaft 14, which is connected to the crankshaft 14 and forms a part of the eccentric rotor shaft 5 via the
It is rotatably supported via a bearing 16 at a position where the eccentricity e is eccentric from .

11 is a double backing mechanism interposed between the outer peripheral wall of the curved end of the crank drum 11 and the inner peripheral wall of the bearing housing 12;
18 is the outer peripheral wall of the eccentric rotor shaft 5 and the crank drum 11
With a double backing mechanism interposed between the inner peripheral wall of the front end,
The spaces between each backing mechanism 11.17 and 18.18 are communicated by a drain hole 19a3 passing through the circumferential wall of the suction housing 12' in front of the bearing housing 12 and a drain hole 20 passing through the circumferential wall of the crank drum 11. .

21 is a gear attached to the outer periphery of the intermediate portion of the crank drum 11.

Reference numeral 22 denotes a Cardan circle gear mechanism that regulates the eccentric rotational motion of the rotor 4 to exhibit hypocycloid motion. When the rotor 4 is rotated, due to the engagement with the wall of the female screw hole 3, the locus of the cross-sectional center 4o of the rotor 4 moves eccentrically so that it draws a straight line reciprocating between X and Y in FIG. Rotor 4 and female screw hole 3
This is for eccentrically moving the eccentric rotor shaft 5 about the axis 2) of the stator 2 so that the cross-sectional center 4o of the rotor 4 traces the same trajectory as described above, regardless of the presence or absence of engagement with the stator 2. As shown in FIG. 7, this gear mechanism 22 has an outer ring internal gear 23 having a gear diameter of four times the eccentricity M%e, that is, 4e, and a gear diameter that is twice the eccentricity e, that is, 2e. The outer ring internal gear 23 is fixed to the rear end of the bearing housing 12 via a housing cover 25 with its axis 23 aligned with the extension of the axis 2 of the stator 2, and the pinion 24 is connected to the crankshaft. axis 14
It is formed at the rear end of the outer ring internal gear 23 and internally meshes with the outer ring internal gear 23.

Next, 26 is a drive shaft to which a motor (not shown) is connected, and this drive shaft 26 is movably supported by a bearing 28 provided in the bearing housing 12-F section and the housing cover 27. A tooth 0E29 that meshes with the gear 21 is attached to the outer periphery of the intermediate portion of the drive shaft 26, so that the crank drum 11 rotates in conjunction with the rotation of the drive shaft 26.

Furthermore, the suction part B is located between the Bon 1 device Δ and the rotor drive bag HD, and consists of a suction port 41 that opens in the -L direction, and a flow path 42 that extends from this suction port 41 to the female screw hole 3 of the stake -2. .

In addition, the discharge port 611C is provided at the rear end of the pump device, and has a discharge port 51 at its tip. If the direction is reversed, they will be swapped.

(Function) Next, the function of the embodiment having the configuration described in - will be explained.

In FIG. 2, when the drive shaft 26 is rotated, the gear 29.
21, the crank drum 11 rotates, and the drum 11
As the crankshaft 14 and eccentric rotor shaft 5 rotate,
rotates eccentrically by e from the extension of the axis 2 of the stator 2, and at the same time, the rotor 4 rotates while engaging with the wall surface of the screw hole 3, and the rotor 4 rotates at each cross section of the female screw hole 3. The cross-sectional center 4o returns in a straight line between FIG. 9 shows the locus of the axis center 5o of the eccentric rotor shaft 5, 5 and 5 in the hole 3, and FIG. However, by comparing both figures, it will be understood that the trajectories of the eccentric shaft 5 and the internal pinion 24 substantially match. That is, the internal pinion 24
The crankshaft 14 has a crank drum 1 at one end.
1, the rotational axis 11 of the crank drum 11
), when it revolves counterclockwise with an eccentricity of e, 7
9 by a single wheel gear mechanism 22,
The axial center 14o of the crankshaft 14 is rotated half a time around the center 3o of the neck screw hole 3.
On the other hand, when the male threaded rotor 4 is engaged and rotated counterclockwise by the eccentric rotor shaft 5 in the female threaded hole 3, the eccentric rotor lllllll15 is drawn as shown in FIG. As shown, it rotates clockwise and its axis center 5o draws a circle with a radius e ([1 - eccentricity ω of the outer shaft 5) around the center 3o of the female threaded hole 3 (
.

10(B) to (d) show the relationship between the movements of the rotor 4 and the eccentric shaft 5 within the female threaded hole 3, and the movement of the internal small gear 24 in the Cardan circle gear mechanism 22.

In this way, the crankshaft 14 driven by the rotor (not shown) works integrally with the eccentric rotor shaft 5 to engage the Mt threaded rotor 4 in the female threaded hole 3 with the inner wall of the female threaded hole 3. Regardless of the presence or absence, the cross-sectional center 4o is rotated so as to linearly reciprocate between X-Y as shown in FIG.

(Effects of the Invention) According to the present invention, the internal threaded hole formed in the stake is formed as an inner surface having an oval cross-sectional shape in the engaging part for the km threaded rotor, and the ul threaded rotor is formed with l[>E].
In a single-shaft eccentric screw pump that engages and rotates around an eccentric rotor shaft of JI e, a crank drum is rotatably disposed with a rotation axis aligned with an extension of the stake-axis line, and the crank drum is used to rotate the above-mentioned Eccentricity of the rotor [The coater shaft is rotatably supported, and the support center position is moved from the rotational axis of the crank drum to the eccentricity (ie) of the rotor.
A small gear having a gear diameter twice the eccentricity e is installed at the rear end of the eccentric rotor shaft, and the small gear is fixed adjacent to the rear end of the crank drum. , and is internally meshed with an outer ring large gear having a diameter four times that of the eccentricity 0, and the rotation of the drive shaft of the drive device is transmitted to the crank drum via the rotation transmission mechanism, and the eccentric rotor shaft [Featured in that the 1-tar is rotated] [The 1-tar driving device has the following effects.]

(1) When transmitting the rotation of the drive shaft of the drive device to the eccentric rotor shaft of the male-threaded rotor, there is no need to use a universal joint or a long connecting shaft as in the past, so the overall length of the pump can be reduced. It can be shortened, made smaller and lighter, and easier to handle.

(The 21M threaded rotor is controlled by a Cardan circle gear mechanism) and is rotated by an eccentric [1-tar shaft] that produces regular bipoly-ilroid motion, so most of the load of the rotor is placed on the inner wall surface of the female threaded hole in the stator. The inner wall surface of the female threaded hole is less likely to get burnt, and since the material selection for the stator is not limited to elastic materials as in the past, a wide range of materials can be used. Even if the precision is high, seizure is less likely to occur and wear is less likely, so pump efficiency is extremely improved.

(3) Since the rotor rotates smoothly and stably, stator fatigue is reduced, and there is no need to replace the stator as frequently as in the past, making maintenance easier and significantly reducing costs.

(4) Since there is no coniversal joint near the entrance of the female screw hole as in the conventional case, the flow path resistance inside the pump is significantly reduced and the pumping capacity is improved, and the pump capacity is improved. Blockage of the flow path due to wrapping is prevented.

[Brief explanation of drawings]

Figure 1 is a cross-sectional view of a conventional uniaxial eccentric screw pump;
The figure is a sectional view showing an embodiment of the present invention, FIG. 3 is a cross-sectional view showing the relationship between the stator screw hole and the rotor, FIG. 4 is a longitudinal sectional view of FIG. Qo, 360° and 120° cross-sectional views of the female threaded hole in Fig. 5.
Figure (b) is a cross-sectional view taken at the same 90° and 450° positions,
Figure 5(C) is a cross-sectional view at the 180° and 540° positions, Figure 5(d) is a cross-sectional view at the 270° and 630° positions, and Figures 6(a) to (d) are female threads. 7 is a schematic front view of the Cardan circle gear mechanism, and FIG. 8 is an eccentric rotor shaft and its center when the rotor engages and rotates in the female threaded hole. Figure 9 is a diagram of the motion trajectory of the internal pinion and its center in the Cardan circle gear mechanism.
Figures (a) to (d) are sectional views corresponding to Figures 6 (a) to (d), showing the relationship between the eccentric rotor shaft and the internal small gear. 1... Stator housing, 2... Stator,
3... Female screw hole, 4... Rotor, 5... Eccentric rotor shaft, 11... Crank drum, 12... Bearing housing, 12'... Suction housing, 14
...Crankshaft, 15...Keyless joint,
13.16...Bearing, 17.18...Double backing mechanism, 19.20...Through hole, 21...Gear,
22... Cardan circle gear mechanism, 23... Outer ring internal gear, 24... Small tooth width, 25.27... Housing cover, 26... Drive shaft, 28... Bearing, 29...
... Gear, 41 ... Suction port, 42 ... Distribution path, 51
...Discharge port, 60...Universal joint, 6
DESCRIPTION OF SYMBOLS 1... Intermediate shaft, A... Pump device, B... Suction part, C... Port 1 outlet part, D... Rotor drive device.

Claims (1)

[Scope of Claims] A neck screw hole formed in the stator is formed as an inner surface of an elliptical shape in the engaging part for the male screw rotor, and the Hl screw rotor is an eccentric rotor shaft with an eccentric amount e. In a single-shaft eccentric screw pump that engages and rotates around the stator axis, a crank drum is rotatably disposed with its rotational axis aligned with the extension of the stator axis, and the eccentric rotor axis of the rotor is rotated by the crank drum. It is rotatably supported, and the support center position is eccentric from the rotational axis of the crank drum by the eccentric amount e, and the eccentricity J'
A small gear with a gear diameter twice that of ie is mounted on the rear end of the eccentric rotor shaft, the small gear is fixed adjacent to the rear end of the crank drum, and a gear with a diameter four times the eccentricity e The crank drum is internally meshed with an outer ring internal gear having a diameter, and the rotation of the drive shaft of the drive device is transmitted to the crank drum via a rotation transmission MM shaft, and the rotor is rotated by an eccentric rotor shaft. A rotor drive device featuring: