JPH10159753A - Inside screw pump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inside screw pump involving less risk of generation of any worn part, assuring a low running cost, and excellent in durability. SOLUTION: Female threads 14 provided in a fixed female screw member 7 are engaged by male threads 20 on a male screw member 11 installed on the crank shaft part 8 of a spindle 5, and a swinging circular motion is given to the male screw member 11 with rotation of the crank shaft part 8 in such a condition as engaged by the female threads 14 so that a pumping action is generated, and thereby generation of friction resulting from rotation is eliminated between the female threads 14 and male threads 20, which should lead to enhancement of the durability and establishment of a low torque arrangement.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an internal screw pump in which a male screw member is eccentrically engaged with a fixed female screw member, and a pumping action is generated by the oscillating circular motion of the male screw member.

[0002]

2. Description of the Related Art Various types and mechanisms of pumps for pumping a fluid have been proposed and put to practical use. Regarding the conventional pump, the pumping action is generated by the rotating motion or the sliding motion in any method and mechanism.

[0003]

However, conventional pumps have a problem that friction is large due to rotation or sliding motion, durability is inferior due to abrasion, and operating cost is high.

Accordingly, an object of the present invention is to provide an internal screw pump in which the pumping action is generated by the oscillating circular motion of the male screw member, the occurrence of frictional parts is small, the durability is excellent, and the operating cost is low. It is in.

[0005]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, an invention according to claim 1 is provided in which an inner peripheral female screw of a fixed female screw member and a crankshaft portion of an input main shaft are rotatable and axially movable. Engaging the external thread of the external thread member mounted so as to be fixed in an eccentric state, and displacing the engagement gap between the internal circumference of the internal thread and the external circumference of the external thread by the oscillating circular motion of the external thread member due to the rotation of the crankshaft. Thus, a configuration in which a pump action is caused by the above is adopted.

According to a second aspect of the present invention, in the first aspect of the present invention, the crankshaft portion of the input main shaft is provided with an inclination angle for absorbing a difference in lead angle between the female screw and the male screw.

According to a third aspect of the present invention, in the first or second aspect of the present invention, a structure is employed in which a rotation preventing mechanism for holding the male screw member in a rotation-locking shape is connected to an end of the male screw member.

According to a fourth aspect of the present invention, in the first or second aspect of the invention, the pressure applied to the male screw member toward the suction port by the discharge fluid is applied to the discharge end of the male screw member. A configuration in which a pressure equilibrium mechanism for reducing pressure is connected is adopted.

According to a fifth aspect of the present invention, a plurality of female screw members are fixedly arranged coaxially, and a plurality of male screw members corresponding to the respective female screw members are rotatably and axially fixed to the crankshaft portion of the input main shaft. The external thread of the external thread corresponding to the internal thread of each internal thread is engaged in an eccentric state, and the internal thread of the internal thread is engaged with the external thread of the external thread by the oscillating circular motion of the external thread member due to the rotation of the crankshaft. The pump action is generated by displacing the gap in the circumferential direction, adjacent male screw members are connected to each other at an angle, and a rotation preventing mechanism is connected to an end of the male screw member.

According to a sixth aspect of the present invention, a male screw member is mounted on a crankshaft portion of an input main shaft passing through a fixed female screw member so as to be rotatable with respect to the crankshaft portion, and the male screw member is prevented from rotating. And the external thread is engaged eccentrically with the internal thread of the internal thread member, and the engaging gap between the internal thread and the external thread is displaced in the circumferential direction by the oscillating circular motion of the external thread member due to the rotation of the crankshaft. This causes a pump action to occur, and a seal mechanism for closing the meshing gap is provided at the discharge-side end of the meshing gap, and the meshing gap is communicated upstream of the sealing mechanism with the male screw member to form a swing. This adopts a configuration in which a discharge mechanism that opens and closes in a moving circular motion is provided.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. FIGS. 1 to 9 show a first embodiment of an internal screw pump, which is rotatably supported by bearings 3 and 4 by a cylindrical casing 1 and a main shaft case 2 fixed to one end of the casing 1. A main shaft 5, an anti-rotation case 6 fixed to the other end of the casing 1, and a casing 1
A female screw member 7 inserted and fixed inside the
A male screw member 11 supported via bearings 9 and 10 on a crankshaft portion 8 coupled to the distal end of the female screw member 7 so as to enter the female screw member 7, eccentrically engaged with the female screw member 7, and housed in the rotation preventing case 6. , The male screw member 11 is held in a non-rotating manner, and the male screw member 1 is
Pressure equalizing mechanism 12 for reducing pressure acting in the axial direction
It is composed of

The casing 1 is provided with a suction port 13 penetrating inward and outward at an end near the main spindle case 2. A female screw member 7 incorporated in the casing 1 has an outside diameter fitted into the casing 1. It is formed in a cylindrical shape, and a female screw 14 of a square thread is provided on its inner peripheral surface. The female screw 14 is inserted into the casing 1 so that the female screw 14 is prevented from rotating with respect to the casing 1 and comes into contact with the pin 15. The position in the axial direction can be adjusted by an adjusting screw 17 screwed into the pin hole 16, and after adjusting the engagement with the male screw member 11, the adjusting screw 17 is fixed to the casing 1 with the mounting screw 18.

The main shaft 5 penetrates the main shaft case 2 in the axial direction, and a pulley 19 for interlocking with a drive source is fixed to an end protruding outside the main shaft case 2. The crankshaft 8 is coupled to the facing end.

The axis of the crankshaft 8 is offset by an eccentricity M and an inclination angle P with respect to the axis of the main shaft 5, the female screw member 7 and the main shaft 5 are coaxially arranged, and the crankshaft 8 is The eccentrically enters the inside of the female screw member 7, and the male screw member 11 is rotatably supported on the crankshaft portion 8 via bearings 9 and 10.

The male screw member 11 has a cylindrical shape in which a male screw 20 of a square screw is formed on the outer peripheral surface, and is attached to the crankshaft 8 with bearings 9 and 10 so as to be coaxial. Therefore, the male screw member 11 has an eccentric amount M inside the female screw member 7.
And an inclination angle P.

The female screw 14 of the female screw member 7 and the male screw 20 of the male screw member 11 have the same cross-sectional shape and lead that can engage with each other, and the inner diameter of the female screw 14 and the outer diameter of the male screw 20 are different. Due to the amount of eccentricity M, the male screw 20 is maximally engaged with the female screw 14 at a part of the outer periphery to form a sealed portion, and the opposite side of the sealed portion and the axis becomes the minimum meshed portion serving as a seal. As described above, the diameter, the thread height, and the eccentricity M are set.

Here, the point at which the ridge of the male screw 20 contacts the valley of the female screw 14 is a push contact A, the point at which the ridge of the female screw 14 contacts the valley of the male screw 20 is a push contact A ', and the push contacts A, A Spaces formed between the peaks and valleys of the part located on the opposite side with respect to 'and the axis are defined as the maximum spaces B and B'.

The male screw member 11 does not move in the axial direction,
The pressure equilibrium mechanism 12 that holds the male screw member 11 in a non-rotating manner so that the male screw member 11 makes a swinging circular motion in the female screw member 7 by the rotation of the crankshaft 8 also serves as a non-rotating mechanism. An anti-rotation bracket 21 is fixed to an end facing the anti-rotation case 6 so as to be movable in the case 6 in an airtight manner in the axial direction, has an end area substantially equal to that of the male screw member 11, and A pressure equilibrium piston 23 serving as a detent is incorporated, and the piston 23 and the rotation preventing bracket 21 are connected to the universal joint 2.
4 and 25 are connected to each other through a rod 26, thereby holding the male screw member 11 in a detent shape and allowing a swinging circular motion. In the case of low-pressure discharge or the like, only a rotation preventing mechanism having a function of simply holding the male screw member 11 in a rotation preventing shape may be used.

In order to reduce the load on the bearing 4 of the main shaft 5 due to the discharge pressure, the suction port 13 and the discharge port 27 provided in the case 6 are set in reverse to the case shown in FIG. A pressure fluid may be sent to the back surface of the housing by a conduit or the like, and the male screw member 11 may be pushed toward the discharge port side.
The air vent hole 28 is unnecessary.

FIGS. 2A and 2B show the engaged state of the male screw 20 and the female screw 14, showing the phase in which the male screw member 11 is eccentric to the uppermost position, and the hatched portion in FIG. In the part where the male screw 20 and the female screw 14 are engaged,
The meshing is maximum at the pressing contacts A and A ', the paired portions are the maximum spaces B and B', and the space between them is the minimum meshing portion C. Further, a blank portion is a space where the pump action is performed, and is maximum in the maximum space portions B and B ′.
It becomes zero at A '. At this time, the outer crescent-shaped space is a space formed in the groove of the female screw 14, and the inner crescent-shaped space is a space formed in the groove of the male screw 20.

FIGS. 4A and 4B show the relationship between the lead angle and the inclination angle of the female screw 14 and the male screw 20.
The pitch X and the lead L of the female screw 14 and the lead L are the same, but since the screw diameters are different, the lead angle β and the twist angle d are different. The smaller the screw diameter, the larger the lead angle β, and conversely, the larger the screw diameter, the smaller the lead angle β.

In a phase in which the eccentric direction of the male screw member 11 is at the maximum, the male screw 20 is inclined with respect to the female screw 14 in a direction perpendicular to the pressing contacts A and A 'to the screw axis. As shown in B), assuming that the lead angle of the male screw 20 is K, the lead angle of the female screw 20 is K ′, and the inclination angle of the difference is P, P = KK−the axis of the male screw 20 with respect to the female screw 14. As shown in FIG. 5, the inclination angle P is given in advance to the crankshaft portion 8 so that the engagement of the male screw 20 with the female screw 14 can be performed without any trouble.

An equation for giving the amount of eccentricity M to the crankshaft portion 8 with respect to the axis of the main shaft 5 is as follows. E = F− (Y−C) M = FE / 2 Here, Y is the height of the screw, C is the minimum engagement amount, F is the root diameter of the female screw 14, and E is the outer diameter of the male screw 20.

Next, the case where the inclination angle P is given to the crankshaft 8 will be described. FIG. 5A shows the main shaft 5 and the crankshaft 8.
(B) is a view of the above as viewed from directly above. With the eccentric part line as a perpendicular, an inclination angle P line intersecting the axis of the female screw and the center of the screw length is drawn in the horizontal direction, and the inclination angle P and the eccentricity M are given to the crankshaft part 8. In this drawing, the drawing is made assuming a right-hand thread, and the crankshaft portion 8 is inclined downward to the right with respect to the front in the axial direction, but in the case of the left-hand thread, the inclination is in the opposite direction. Although the actually used inclination angle P is as fine as about 1 °, it is exaggerated in the figure.

FIG. 6 illustrates the relationship between the center of the female screw 14 and the center of the male screw 20 when the male screw member 11 is provided with the tilt angle P. The axial contact causes the push contact A to be on the S dotted line of the female screw 14. , N deviate from the center line. FIG.
(B) to (D) are diagrams schematically illustrating a certain point on the dotted line S, and the gap W is zero at the center of the length and becomes maximum at both ends. Here, the gap W is RM. If one of the circumferences of the female screw 14 and the male screw 20 to be pressed and contacted is made a straight line, the opposite circumference may be corrected by the numerical value of the gap W, but this numerical value is very small and does not substantially affect the accuracy in practice. There are cases.

FIG. 3 shows the relationship between the engaging portions of the female screw 14 and the male screw 20. The female screw 14 and the male screw 20 are four-threaded right-hand screws, as viewed from the suction side. When the male screw 20 is tilted by the tilt angle P, the maximum koze occurs at the portions T and T 'at positions 90 ° on both sides with respect to the push contact A. In order to solve this, male screw 20
By making the threads of P angle inclined at the P angle, it is possible to seal the push contacts A and A ', and the thread angles of both screws and the screw side face can swing smoothly without gaps, and the occurrence of koze can be prevented. it can. However, the maximum space B in the lower part of FIG.
A clearance U occurs in the minimum meshing portion C of B '. Note that arrows in portions T and T ′ in FIG. 3 indicate the direction in which the fluid is discharged.

In the figure, the valley groove of the female screw 14 is opened at four positions at both ends of the female screw member 7, and the opening at the end face on the suction port 13 side is the suction port 1.
4a, 14b, 14c, and 14d.
The four portions that open at the end face facing the side
14h.

Similarly, the valley groove of the male screw 20 has four portions opened at the end face on the side of the suction port 13 at the suction port 20a,
20b, 20c, and 20d, and four portions opened at the end face facing the ejection port 27 side are ejection ports 20e to 20h.
Becomes

FIG. 7 shows a male screw and a female screw for preventing leakage of the gap U at the position of the maximum space B when a pumping operation is performed by engaging the fixed female screw 14 and the male screw 20 that oscillates in a circular motion. FIG. 4 is an explanatory view, in which the female screw 14 and the male screw 20 are four-threaded screws of the lead L, and the overall length 1 of the screw is increased by one pitch or ピ ッ チ pitch. In this figure, the upper and lower pressing contacts A are the same pressing contact, and the upper part represents the front of the oscillating circular motion of the male screw 20 and the lower part represents the rear.

H, F, H 'and F' on the pressing contact A are the lengths of the leads L from 1 pitch to 4 pitches.
The inside of the triangle of H ′ is open at the end face on the discharge side, and the inside of this triangle is a high-pressure part. The inside of the triangle of F, H 'and F' is a sucked fluid and is a low pressure part.

The horizontal line at the center is the maximum space B, B 'line, and no leakage injection occurs in the triangle of the high pressure part and the bottom pressure part. However, the oblique lines of H', F and the maximum space part B, B 'line Are the maximum leak gap U. Since the fourth pitch is at a high pressure and the adjacent first 'pitch is at a low pressure, leakage occurs from the gap U. In order to prevent this leakage to the outside, if the total screw length l is made longer than the lead L by one pitch or 1/2 pitch, the male screw 20 and the female screw 14 are present within 1 pitch or 1/2 pitch. Since it acts as a seal and closes the leak with the push contact A, the leak circulates around the circumference of the gap U and does not cause any negative effect on the discharge action. Occurs.

FIG. 9 shows the means for adjusting the meshing portion between the female screw member 7 and the male screw member 11. The inner circumference of the female screw member 7 and the outer circumference of the male screw member 11 are formed on the inclined surface in the same direction. At the time of the meshing of 20, the position of one of the female screw member 7 and the male screw member 11 is adjusted in the axial direction, and a portion where resistance is less generated is set at the meshing portion.

The inclined surfaces provided on the female screw member 7 and the male screw member 11 may have the peaks and valleys of the female screw 14 and the male screw 20 linearly inclined in the axial direction as shown in FIG.
As shown in (C), the peaks and valleys of the female screw 14 and the male screw 20 may have a cross-sectional shape that is gradually inclined in the axial direction.

The internal screw pump according to the first embodiment has the above-described configuration. When the main shaft 5 is rotated by the driving source, the crankshaft 8 rotates eccentrically about the axis of the main shaft 5. The male screw member 11 mounted on the crankshaft portion 8 via the bearings 9 and 10 performs a oscillating circular motion in the female screw member 7 which is fixedly arranged. The push contacts A and A 'are moved in the circumferential direction while maintaining the engagement of the entire circumference of the male screw 20 with respect to the circumference. 8 (A) to 8 (D) show the steps of this discharge action in order and in an easy-to-understand manner.

Accordingly, the screw-like space formed between the female screw 14 and the male screw 20 causes the suction and discharge operations due to the transition of the push contacts A and A ′, and the fluid flows at the portion where the end on the suction port 13 side is opened. At the same time as the suction, the pressure fluid is pumped toward the discharge port 27 at a portion where the end on the discharge port 27 side is opened.

The discharge pressure fluid is supplied to the rotation preventing bracket 21.
And acting on the opposite side of the pressure parallel piston 23,
It is possible to prevent an excessive load from acting on the male screw member 11 and to efficiently discharge the fluid under a low load condition.
Used as a pump or compressor.

Next, a second embodiment shown in FIGS. 10 to 13 will be described. The second embodiment is a double internal screw pump using two sets of the female screw member 7 and the male screw member 11 of the above-described first embodiment. Are denoted by the same reference numerals and description will be omitted.

In the second embodiment, both ends of a horizontal main shaft 5 located in the casing 1 are rotatably supported via bearings 31 and 32. The sleeve 34 connected so as to rotate integrally is fixed in the axial direction by a tightening nut 35 screwed to the main shaft 5.

The outer diameter of the sleeve 34 is as shown in FIG.
The crank is formed by being eccentric with respect to the axis of the main shaft 5 by an eccentric amount M, and the outer diameter of the sleeve 34 is provided with an inclination angle P that is inclined in the opposite direction with respect to the center portion in the length direction. Have been.

Male screw members 11 and 11 ′ are mounted at positions on both sides of the longitudinal center portion of the sleeve 34 via bearings 36 so as to be free in the rotational direction.
The female screw members 7, 7 'are fixed at positions corresponding to the two male screw members 11, 11' in the casing 1, and the male screw members 11, 11 'correspond to the male screws 20, as in the first embodiment. It engages with the female screw 14 of the female screw members 7, 7 '.

The male screw 20 of the male screw member 11 meshing with each other
The female screw 14 of the female screw member 7 naturally has the same inclination in the same direction, but the male screw members 11 and 11 'on both sides have the male screw 20, 20' inclined in the opposite direction, and the female screw members 7, 7 '.
The female screw 14 is also inclined to match this.
The fluids are ejected toward each other.

Accordingly, the casing 1 is provided with the discharge port 27 at a position corresponding to the space between the female screw members 7, 7 'on both sides, and the suction ports 13, 13 at the opposite ends of the female screw members 7, 7'. 'Is provided.

The anti-rotation mechanism 37 connected to the male screw member 11 fixes the disk-shaped portion of the anti-rotation bracket 38 which is fitted to the sleeve 34 to the end of the male screw member 11 by fastening with a bolt or the like. The boss 41 of the forked slide 40 is swingably connected to the forked slide receiver 39 provided at a plurality of positions 38 by a connecting pin 42 perpendicular to the main shaft 5 and fixed to the end of the casing 1. A plate slide 4 is attached to a plurality of forked brackets 44 provided on the plate 43.
The boss portion 46 is swingably connected to the main shaft 5 by a pin 47 in a direction perpendicular to the main shaft 5, and the plate slide 45 is fitted in the forked slide 40. With such a structure, the swinging circular motion is allowed while the male screw member 11 is held in a detent shape.

The two male screw members 11, 1 'are so made that both male screw members 11, 11' make a swinging circular motion in a non-rotating manner.
As shown in FIG. 13, crown gears 48 and 49 meshing with each other are provided at opposite ends of 1 '. The meshing portions of the crown gears 48 and 49 are inclined, and the two male screw members 11 and 11 ′ are allowed to allow the oscillating circular motion of the two male screw members 11 and 11 ′ having the inclination angle P in opposite directions.
Is approximately twice as large as the inclination angle P.

Since the meshing portion between the two crown gears 48 and 49 just faces the discharge port 27, the discharge fluid flows around the outer circumference of the two crown gears 48 and 49, and the male screw member 11,
A seal mechanism 50 for preventing intrusion into the internal space of 11 'is provided.

The seal mechanism 50 of the first example shown in FIG. 13B has a spherical portion 5 on the outer peripheral surface of both crown gears 48 and 49.
1 and 52 are provided, and a cylindrical seal ring 53 is fitted around the outer surfaces of both spherical portions 51 and 52 so as to be in close contact with each other. A seal is made between the two.

The seal mechanism 50 of the second example shown in FIG. 13C has annular concave grooves 54, 55 provided on the outer peripheral surface of the crown gears 48, 49, and is provided on the outer periphery of both crown gears 48, 49. The inner peripheral surface of the externally inserted seal ring 56 is
55 is pressed into contact with O-rings 57, 58 made of rubber or the like fitted in the 55, and the crown gears 48, 49 and the seal rings 57, 5
The seal 8 is used.

The internal screw pump according to the second embodiment has the above-described structure. When the main shaft 5 is rotated, the male screw members 11 and 11 ′ on both sides swing circularly in the female screw members 7 and 7 ′. Then, the fluid sucked from the suction ports 13 and 13 ′ is sent out toward the discharge port 27 side, and the discharge capacity is improved as compared with the first embodiment by the two sets of pump action.

The third embodiment of the internal screw pump shown in FIGS. 14 to 20 supports both ends of the input main shaft and frees the axial bearing of the male screw member to stabilize the position by meshing the screws. Further, the discharge pressure can be improved, and the same parts as those in the first embodiment will be described using the same reference numerals.

As shown in FIG. 14, the cylindrical casing 6
1 are closed at both ends by end plates 62 and 63, and one end of the main shaft 5, which penetrates one end plate 62 and is supported by the bearing 63, is connected to the other end plate 6.
An eccentric crankshaft 8 is provided in the middle of the main shaft 5 which is supported by a bearing 3 via a bearing 64 and is rotatable coaxially with the casing 61.

A cylindrical female screw member 7 is coaxially fixed at an intermediate position inside the casing 61, and a male screw member 11 attached to the crankshaft 8 via bearings 65 and 66 is inside the female screw member 7. The male screw 20 formed on the outer circumference of the male screw member 11 is
4 is eccentrically engaged.

The male screw member 11 is mounted so as to be rotatable and movable in the axial direction with respect to the crankshaft 8 by being supported by bearings 65 and 66, and the engagement between the male screw 20 and the female screw 14 is the first. The conditions are the same as in the embodiment.

The suction ports 13 are provided at both ends of the casing 61.
And a discharge port 27, a rotation prevention mechanism 67 for the male screw member 11 is provided inside the casing 61 at a position on the suction port 13 side, and a shaft seal mechanism 68 and a male screw 20 are provided at a position on the discharge port 27 side. A sealing mechanism 69 for closing the discharge side end of the meshing gap between the female screw 14 and the discharge mechanism 70 communicating with the meshing gap on the upstream side of the seal mechanism 69 and opening and closing by a swinging circular motion integrated with the male screw member 11. Is provided.

The rotation preventing mechanism 67 includes a crankshaft 8
When the rotation of the male screw member 11 is performed, a swinging circular motion is generated without rotating the male screw member 11.
14 and 15, a circular anti-rotation plate 72 is disposed between the bracket 71 and the end plate 62 of the casing 61, as shown in FIGS. The slide groove 73 is provided at the position of
The rollers 75 of the pins 74 fixed to the rotation prevention bracket 71 are fitted into a pair of slide grooves 73 opposed to each other with the axis interposed therebetween, and the remaining pair of slide grooves 73 are fitted with pins 76 fixed to the end plate 62. The roller 77 is fitted.

As a result, the male screw member 11 is held in a non-rotating manner via the rotation preventing plate 22, and the oscillating circular motion having the eccentric amount M as a radius becomes possible.

The shaft seal mechanism 68 includes the male screw member 1.
The bearing press 78 of the seal press 80 is inserted into the crankshaft 8 so as to be movable in the axial direction so as to be movable in the axial direction.
, And a spherical seal 81 having a spherical back surface is held by a spring 82 contracted between the seal retainer 80 and the end plate 63 via the seal retainer 80.
Is constantly pressed against the bearing retainer 78.

With such a structure, the spherical seal 81 follows the deflection of the end face of the male screw member 11 at the inclination angle P and maintains the sealing state with respect to the main shaft 5 side. 81 adjusts the outer diameter to balance the pressure in the axial direction on which the discharge pressure fluid acts, and provides bearings 65 and 66 for supporting the male screw member 11.
Is free in the axial direction, the position of the male screw member 11 in the axial direction can be stabilized by the engagement condition between the male screw 20 and the female screw 14. It is possible to support the bearings 63 and 64, so that there is an advantage that the assembling operation can be simplified and the occurrence of wear of the male screw 20 and the female screw 14 can be reduced.

As shown in FIG. 16, the sealing mechanism 69 includes a closing screw 83 which is externally fitted to a portion of the male screw member 11 projecting from an end of the female screw member 7, and a sealing screw 83 of the male screw member 11. A detent plate 85 in which the inner periphery is engaged with an axial groove 84 formed on the outer peripheral surface of the end portion and which comes into contact with the end surface of the closing screw 83.
And externally threadedly engaged with the end of the male screw member 11,
And a nut member 86 for tightening and fixing the rotation preventing plate 85 to the male screw member 11, and a partition plate 8 fitted externally to the closing screw 83.
7, a holding plate 88 for fixing the partition plate 87 to the female screw member 7 while holding the partition plate 87 in such a manner as to enable swinging circular motion, and incorporating the partition plate 87 at a position closer to the inner periphery between the opposing surfaces of the partition plate 87 and the female screw member 7. It is constituted by a plurality of ring-shaped seal plates 89.

As shown in FIGS. 16, 18 and 19, the closing screw 83 is provided in the groove between the threads of the male screw member 11 on the inner periphery of the annular portion 90 having a larger diameter than the male screw 20. Screws 91 of about a half circumference are provided by the number of grooves.

The outer diameter of the portion of the screw 91 protruding from the annular portion 90 matches the crest diameter of the male screw 20, and the tip of the screw 91 forms a gap 92 with the end face of the female screw 14 as shown in FIG. In order to prevent trouble even when the inclination angle P is generated, the processing is performed so as to be thinner toward the tip.

The partition plate 87 has a ring shape having an inner diameter that fits into the annular portion 90 of the blocking screw 83 and an outer diameter that has a gap that allows a swinging circular motion with respect to the inner diameter of the casing 61. And the outer diameter of the detent plate 85 is coupled with the groove 93 and the square projection 94 to form a detent, and the closing screw 83 is fitted to the outer peripheral arc-shaped portion 90a of the annular portion 90. The portion imparts an oscillating circular motion integral with the male screw member 11.

The holding plate 88 can be fixed to the female screw member 7 by providing cutouts at a plurality of locations on the outer periphery of the partition plate 87 and fixing the holding plate 88 to the female screw member 7 with bolts that fit into the cutouts with play. The partition plate 87 can perform the swinging circular motion without any trouble.

The inner circumference of the partition plate 87 has an external thread 2
A contact portion 95 that fits into the ridge diameter of 0 and abuts against the end face of the annular portion 90 of the blocking screw 83 is provided around the contact portion 95.
A seal plate 89 is installed between the end face of the internal thread member 7 and the internal thread member 7.

In the case of FIG. 17, three thin ring-shaped seal plates 80 are used, and the contact portion 95 and the female screw member 7 are used.
The inner diameter of each seal plate 89 is fitted to the outer diameter of the male screw 20 and the outer diameter of the screw 91 in the closing screw 83. The inner diameter is such that the male screw 20 and the screw 91 have the inclination angle P
It becomes a curved surface that prevents stiffness even if you only tilt it,
As shown in FIGS. 17A and 17B, each seal plate 89 is located at a different position according to the inclination angle.
The external thread 20 and the screw 91 are smoothly sealed.

The discharge mechanism 70 discharges a pressurized fluid by increasing the internal pressure of the pump formed by the engagement gap between the male screw member 11 and the female screw member 7 and discharges a gas or a mixture of a gas and a liquid. Suitable for.

As shown in FIGS. 14 and 16, the discharge mechanism 70 extends outward from the ridges and valleys at the ends of the female screw member 7 at the end of the female screw 14, and at the overlapping surface of the partition plate 87. The male screw member 1 is provided with a discharge hole 96 that is opened, a partition hole 97 that penetrates through the partition plate 87 in the axial direction, and a pressing plate 88 that is provided with openings 98 in a number corresponding to the discharge holes 96.
When the partition plate 87 makes a swinging circular motion integrally with the first member 1, the position of the partition hole 97 changes, so that the communication between the discharge hole 96 and the opening 98 is established and blocked.

FIG. 19 shows a change in the phase in the discharge mechanism 70. In FIG. 19, assuming that the discharge hole 96 of No. 1 communicates with the valley space of the female screw 14, No. 3 and No.
The discharge holes 96 at the positions of No. 5 and No. 7 are under the same conditions.
The discharge holes 96 at the positions No. 2, No. 4 and No.
And open to the valley space of the male screw 20 to communicate with the valley space of the male screw 20.

No. 1 is the position of the push contact A of the male screw 20 and the female screw 14. This push contact moves counterclockwise from No. 1 to No. 8 by the oscillating circular motion of the male screw member 11. By this movement, No. 1 changes to No. 2 phase, and No. 8 changes
It becomes the state of No.1.

The phase of No. 1 is the end of the discharge step and the start of compression in the pump. The partition hole 97 is slightly communicated with the discharge hole 96, and the partition hole 97 is just before the communication is closed.

The cut hole 97 of the No. 2 phase is
And the opening 98 are closed, and such a sealing state continues until the phase of No. 5,
From No. 6 to No. 7, No. 8, and No. 1, the discharge step is one in which the partition hole 97 communicates the discharge hole 96 and the opening 98.

As described above, when the opening and closing of the discharge mechanism 70 is performed in response to the movement of the push contact A, the discharge can be performed after the pressure of the fluid is increased in the pump. This prevents backflow into the pump and saves energy.

The internal screw pump according to the third embodiment has the above-described configuration. When the main shaft 5 is rotated, the male screw member 11 performs a oscillating circular motion, similar to the first embodiment.
Female screw 14 of female screw member 7 and male screw 2 of male screw member 11
When 0, a pump action is generated, the fluid sucked from the suction port 13 is pressurized, and the pressurized fluid is sent out from the open portion of the discharge mechanism 70 toward the discharge port 27.

[0073]

As described above, according to the first to fifth aspects of the present invention, the male screw member is engaged in the fixed female screw member, and the male screw member is given a oscillating circular motion to generate a pump action. Since the male screw makes an oscillating circular motion, not a rotation, with respect to the female screw, the coefficient of friction is very small, the operating cost is small, and the pump is excellent in wear resistance and durable.

According to the sixth aspect of the present invention, the fluid can be discharged in a pressurized state at the engagement portion between the female screw member and the male screw member, the discharge efficiency is improved, and the gas or the mixed gas of the gas and the liquid can be discharged. It is suitable for the discharge.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a first embodiment of an internally threaded pump.

FIG. 2A is a cross-sectional plan view showing the relationship between a female screw member and a male screw member in the above, and FIG.

FIG. 3 is an explanatory view showing a relationship between a female screw member and a suction port side of a male screw member and respective engagement portions;

FIGS. 4A and 4B are explanatory diagrams showing a relationship between a female screw and a male screw;

FIGS. 5A and 5B are explanatory diagrams showing the relationship between the eccentricity and the inclination angle between the main shaft and the crankpin.

FIGS. 6A to 6D are explanatory views showing the relationship between the inclination angles of a female screw member and a male screw member.

FIG. 7 is a developed view showing a relationship between a female screw and a male screw.

FIGS. 8A to 8D are stroke diagrams showing a pump action.

FIGS. 9A to 9C are explanatory views showing a means for adjusting engagement of a female screw member and a male screw member.

FIG. 10 is a longitudinal sectional view showing a second embodiment of the internally threaded pump.

FIG. 11 is an explanatory diagram showing a relationship between a main shaft and a crank in the above.

FIG. 12 is an exploded perspective view showing a main part of a rotation prevention mechanism.

13A is a longitudinal sectional side view showing an end surface of a male screw member, FIG. 13B is a sectional view showing a first example of a sealing mechanism,
(C) is a cross-sectional view showing the second example.

FIG. 14 is a longitudinal sectional view showing a third embodiment of the internally threaded pump.

FIG. 15 is a longitudinal sectional side view of a rotation stop mechanism.

FIG. 16 is an enlarged sectional view of a seal mechanism and a discharge mechanism.

17A and 17B are enlarged sectional views of a sealing mechanism.

18 (A) and (B) are perspective views of a closing screw.

FIG. 19 (A) is a front view of a closing screw, and FIG. 19 (B) is FIG.
Cross-sectional view taken along arrow BB of FIG.

FIG. 20 is an explanatory view showing a discharge process of a discharge mechanism.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Casing 5 Main shaft 6 Rotation prevention case 7, 7 'Female screw member 8 Crank shaft part 11, 11' Male screw member 12 Pressure equilibrium mechanism 13, 13 'Suction port 14 Female screw 15 Detent pin 20 Male screw 27 Discharge port 34 Sleeve 37 Rotation prevention Mechanisms 48, 49 Crown gear 50 Seal mechanism 67 Non-rotating mechanism 68 Shaft seal mechanism 69 Seal mechanism 70 Discharge mechanism

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Hiroyuki Miyashita 655-4 Totobori, Himeji-shi (72) Inventor Yukio Matsumura 155-2 Suka, Shima, Himeji

Claims (6)

[Claims] An eccentric engagement between an inner peripheral female screw of a fixed female screw member and an outer male screw of a male screw member mounted on a crankshaft portion of an input main shaft so as to be rotatable and fixed in an axial direction. An internal screw pump in which a pumping action is generated by displacing a meshing gap between the inner circumference of the female screw and the outer circumference of the male screw in the circumferential direction by the swinging circular motion of the male screw member caused by rotation of the portion. 2. The internal screw pump according to claim 1, wherein the crankshaft portion of the input main shaft is provided with an inclination angle for absorbing a difference in lead angle between the female screw and the male screw. 3. The inner screw pump according to claim 1, wherein a rotation preventing mechanism for holding the male screw member in a detent shape is connected to an end of the male screw member. 4. A pressure balancing mechanism for reducing the pressure applied to the male screw member toward the suction port by the discharge fluid by using the pressure of the discharge fluid is connected to the discharge side end of the male screw member. Internal screw pump as described. 5. A plurality of female screw members are fixedly arranged coaxially, and a plurality of male screw members corresponding to the respective female screw members are mounted on the crankshaft of the input main shaft so as to be rotatable and fixed in the axial direction. The external male screw of the male screw member corresponding to the internal female screw of the female screw member is eccentrically engaged, and the engaging gap between the female screw inner circumference and the male screw outer circumference in the circumferential direction by the oscillating circular motion of the male screw member due to rotation of the crankshaft portion. An internal screw pump in which a pumping action is generated by displacing, adjacent male screw members are variably connected to each other, and a rotation preventing mechanism is connected to an end of the male screw member. 6. A male screw member is mounted on a crankshaft portion of an input main shaft penetrating a fixed female screw member so as to be rotatable with respect to the crankshaft portion. The outer peripheral male screw is eccentrically engaged with the inner female screw of the female screw member, and the engaging action between the inner circumference of the female screw and the outer circumference of the male screw is displaced in the circumferential direction by the oscillating circular motion of the male screw member due to the rotation of the crankshaft portion. At the discharge side end of the meshing gap, and a sealing mechanism that closes the meshing gap, and communicates with the meshing gap upstream of the sealing mechanism, and opens and closes in a swinging circular motion integral with the male screw member. Internal screw pump with a discharge mechanism that performs