KR20160132039A - Pump device - Google Patents

Abstract

An object of the present invention is to suppress formation of a step of a rotor of an internal gear pump and to prevent formation of a gap on an end surface (side surface) of an inner rotor and an outer rotor to prevent a decrease in volume efficiency. To this end, the pump device of the present invention is provided with an internal gear pump 10 in which an inner rotor 13 is in contact with an outer rotor 12, a plate-like member 7 is provided on an end face of the rotor, The member 7 is made of a material having a high hardness and has a through hole 73 formed in a shape that does not close the suction port 150. O-ring grooves 71, 72 are formed.

Description

[0001] PUMP DEVICE [0002]

The present invention relates to an internal gear pump.

The gear pump includes an external gear pump and an internal gear pump (e.g., Trochoid pump: TM). Conventionally, an internal gear pump is used in a relatively low pressure region, as compared to an external gear pump. Recently, there has been proposed an internal gear pump in which cooling water (cooling fluid, cutting fluid) is used as a working fluid (see, for example, Patent Document 1).

However, since hard foreign matters (particles) are present in the cooling water, the rotor of the internal gear pump is worn by the hard foreign matter. When the rotor is worn, a clearance is formed on the end surface (side surface) of the inner rotor and the outer rotor, which results in a problem that the volume efficiency is lowered and the discharge amount is lowered. At present, no effective countermeasure against the problem related to the internal gear pump is proposed.

International Patent Publication No. 2012/053231

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems in the prior art, and it is an object of the present invention to suppress wear of a rotor of an internal gear pump and to suppress formation of a gap in an end face (side face) of an inner rotor and an outer rotor, And to provide a pump device capable of preventing the above problems.

The pump devices 100 to 100C and 200 to 200C of the present invention are provided with an internal gear pump 10 in which inner rotors 13 and 213 are in contact with outer rotor 12 and 212, Plate members (balance plates 7, 7A, 207, and 207A) are provided on the end faces (the end faces on the suction side end side: the end faces on the side away from the drive source) of the inner rotor And the plate members (balance plates 7, 7A, 207, 207A) are made of a material having a high hardness and are formed in a shape that does not block the suction ports 150 (Pi) Ring grooves 71, 71A, 72, 72A, 207a, 207b, 207k, and 207j in which the O-rings are accommodated in a continuous shape.

In the present invention, the O-ring grooves (71, 72, 207a, 207b) are formed on the side of the plate member (balance plate (7, 207) (71, 72, 07a, 207b).

Alternatively, in the present invention, it is preferable to form a blind hole space BH on the side opposite to the rotor of the plate member (balance plate 7A, 207A) and to accommodate the elastic member 9 in the blind hole space BH Do.

In the present invention, the second plate member (fixing plate 8) is disposed on the end face opposite to the plate member (balance plate 7, 7A, 207, 207A) of the rotor, and the second plate member 8 Is preferably a shape that does not close the discharge port 140. [

Further, in the present invention, the internal gear pump may be arranged such that the suction side and the discharge side of the working fluid are located on the other side with respect to the rotation axis direction of the rotor. Alternatively, the suction side and the discharge side of the working fluid may be disposed on the same side with respect to the rotation axis direction of the rotor.

According to the present invention having the above-described configuration, the plate members (the balance plates 7, 7A, 207, and 207) are provided on the end faces (the end faces on the suction side: the end faces on the side remote from the drive source) of the rotors (the outer rotor and the inner rotor) 207A) is formed of a material having a high hardness so as to form a through hole (discharge pressure introduction hole) in a shape that does not block the suction port 150 (Pi) Holes 73 and 73A through the gap between the outer rotor 12 and 212 and the inner rotor 13 and 213 and the through holes (discharge pressure introduction holes 73 and 73A) 7A, 207, and 207A) is introduced into the side surface of the rotor that is spaced apart from the rotor. Ring grooves 71, 71A, 72, 72A, 207a, 207b, 207k and 207j are formed on the plate members (balance plates 7, 7A, 207 and 207A) Therefore, even when the discharge pressure is introduced into the plate members 7, 7A, 207, 207A and the pressurized working fluid is supplied, leakage is prevented by the O-ring.

The area of the region where the discharge pressure of the sheet members 7, 7A, 207 and 207A is introduced is larger than the area of the region where the discharge pressure of the gap between the outer rotor 12, 212 and the inner rotor 13, The plate members 7, 7A, 207, and 207A are pressurized to the rotor side (the discharge side of the first to fourth embodiments: the left side of FIG. 1). Even when the discharge pressure becomes negative or negative, the tightening margin of the O-ring and the elastic repulsive force of the elastic member (spring 9) are pressed by the rotors 12, 13, 212, (7, 7A, 207, 207A).

According to the present invention, since the plate members (7, 7A, 207, 207A) are made of a material with high hardness, they are not worn. The side surfaces of the rotors 12, 13, 212 and 213 are worn, but the plate members 7, 7A, 207, and 207A, which are pressed against the rotor, , 13, 212, and 213 are not worn in a concavo-convex shape. The plate members 7, 7A, 207, and 207A move toward the rotor side to compensate for the clearance (due to abrasion) as much as the rotors 12, 13, 212, and 213 are worn. As a result of the reduction of the clearance (clearance), the volume efficiency is improved by the pump device of the present invention. Since the plate members 7, 7A, 207 and 207A are shaped so as not to block the side of the intake port 150 (Pi), the plate members 7, 7A, 207 and 207A are installed, The fluid suction is not inhibited.

Here, since the force for pressing the plate members 7, 7A, 207, 207A to the rotor side is obtained from the discharge pressure of the internal gear pump, the discharge pressure does not act on the plate member at the time of operation of the internal gear pump. However, in the present invention, the plate members (7, 7A, 207, 207A) can be pressed against the rotor side by an external mechanical force other than the discharge pressure of the internal gear pump. For example, the O-ring is disposed on the side opposite to the rotor of the plate members 7 and 207 so that the O-ring has a predetermined tightening margin in the O-ring grooves 71, 72, 207a and 207b And the plate-like members 7 and 207 are pressed against the rotor side by causing the elastic reaction force of the O-ring to act on the plate members 7 and 207. As a result, Alternatively, by forming a blind hole space BH in the end surface of the plate members 7A and 207A opposite to the rotor and accommodating the elastic member 9 in the blind hole space, the elastic member 9 (spring) The elastic reaction force of the plate members 7A and 207A acts on the plate members 7A and 207A to press the plate members 7A and 207A toward the rotor.

Thus, in the present invention, the plate members (7, 7A, 207, 207A) are pressed against the rotor side even when the internal gear pump is started. As described above, the plate members 7, 7A, 207, and 207A made of a material with high hardness are kept flat without being worn, so that the sides of the pressed rotors 12, 13, 212, It does not wear out. The plate members 7, 7A, 207, and 207A move toward the rotor by the wear amount of the rotors 12, 13, 212, and 213 to reduce the clearance (due to wear), thereby improving the volume efficiency.

1 is a front sectional view of a first embodiment of the present invention.
2 is a rotor side view of the internal gear pump in the first embodiment.
3 is a view showing a balance plate in the first embodiment.
Fig. 4 is a front view showing the vicinity of the balance plate in partial cross section in the first embodiment. Fig.
5 is a view showing a fixing plate in the first embodiment.
6 is a front sectional view showing the second embodiment of the present invention.
7 is a front sectional view showing the third embodiment of the present invention.
8 is a view showing a balance plate in the third embodiment.
Fig. 9 is a front view showing the vicinity of the balance plate in partial cross section in the third embodiment. Fig.
10 is a front sectional view showing the fourth embodiment of the present invention.
11 is a front sectional view showing a fifth embodiment of the present invention.
12 is a side view of the fifth embodiment (a view seen from an arrow Y direction in Fig. 11).
13 is a front sectional view showing the sixth embodiment of the present invention.
14 is a front sectional view showing the seventh embodiment of the present invention.
15 is a front sectional view showing an eighth embodiment of the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. First, a first embodiment of the present invention will be described with reference to Figs. 1 to 5. Fig. In Fig. 1, the pump device shown as 100 in its entirety is provided with an internal gear pump 10. The internal gear pump 10 includes a gear case 11, an outer rotor 12, and an inner rotor 13. 1, reference numeral 14 denotes a pump housing, and reference numeral 15 denotes a pump lower end plate (hereinafter abbreviated as "end plate"). The inner rotor 13 is fixed to the rotary shaft 5 by a key not shown. The manner of boosting the working fluid by the engagement of the outer rotor 12 and the inner rotor 13 is shown in Fig.

2, the internal gear pump 10 of the embodiment rotates in the same direction while engaging the seven internal teeth 12t of the outer rotor 12 and the six external teeth 13t of the inner rotor 13 Arrow R direction). The working fluid is boosted by engaging the seven internal teeth 12t of the outer rotor 12 and the six external teeth 13t of the inner rotor 13. [

In Fig. 2, the working fluid in the area E1 subjected to hatching is boosted. The working fluid raised in the area E1 (Fig. 2) flows from the discharge port 140 (indicated by a dotted line in Fig. 2) formed on the end surface of the rotor 12, 13 side to the pump housing 14 (1) through the discharge passage 141 of the discharge port 142 and the discharge port 142.

1, the pump apparatus 100 is provided with a primary cyclone 40 in a cyclone casing 45 and a plurality of secondary cyclones 50 in a radially outer side of the primary cyclone 40 . The primary cyclone 40 and the secondary cyclone 50 are tapered members whose diameters decrease toward the lower end (the foreign matter discharge ports 42, 52). An inlet 45i for withdrawing working fluid is formed near the lower end of the cyclone casing 45. [ The pump device 100 also has an impeller 30 (cyclone relay impeller) accommodated in the impeller housing 31.

A tapered guiding member 55 is disposed below the primary cyclone 40 and an impeller 60 for discharging foreign matter is provided below the primary cyclone 40. The inner rotor 13, the cyclone relay impeller 30 and the impeller 60 for discharging the foreign matter are fixed to the rotary shaft 5 and are rotationally driven by an electric motor (not shown).

Flows F1 to F11 (Fc1 to Fc4) of the working fluid flowing from the inlet port 45i of the pump device 100 will be described. The working fluid F1 flowing in from the inlet 45i rises in the cyclone case 45 (arrow F2) and flows back into the primary cyclone 40 (arrow F3) from the ceiling portion of the guide member 312.

The working fluid introduced into the primary cyclone 40 is attracted by the rotary shaft 5 and descends in the form of a vortex while rotating around the outer periphery of the rotary shaft (arrow F4), and the foreign matter having a large specific gravity (for example, (Arrow Fc1 indicated by a dotted line), the clean working fluid is sucked by the rotating centrifugal force of the cyclone-relay impeller 30 and is discharged through the fluid inlet port 313 And rises to the position of the cyclone relay impeller 30 (arrow F5). The working fluid, which is subjected to the centrifugal force by the rotation of the cyclone relay impeller 30, is stepped up and flows into the second impeller 50 (arrow F6).

The working fluid introduced to swing along the inner wall surface at the upper portion of the secondary cyclone 50 descends while drawing a spiral shape (arrow F7), and the suction pipe 21 is rotated by the suction negative pressure formed at the gear pump 10 side The heavy foreign substances having a large specific gravity do not follow the upward flow of the working fluid and drop downward to be discharged from the foreign matter discharge port 52 to be guided by the tapered guiding member 55 (Arrow Fc2 indicated by a dotted line in Fig. 1), and the cleaned fluid only rises by separating the foreign matters in two stages by the first and second cyclones, and the suction pipe 20, which is provided on the suction plate 20, (Arrow F8). The working fluid passes through the flow path 22 of the suction plate 20 and sucked into the internal gear pump 10 from the suction port 150 of the end plate 15 (arrow F9). And is discharged from the discharge port 142 of the pump housing 14 via the discharge port 140 and the discharge passage 141 of the pump housing 14 (arrow F10, arrow F11, ). A part of the working fluid (indicated by arrow F10R) boosted by the internal gear pump 10 is introduced into the discharge pressure introducing hole 73 (Fig. 3) formed in the balance plate 7, as will be described in detail later. The operation fluid (arrows Fc1 and Fc2 in Fig. 1) including the foreign matter discharged from the foreign matter discharge port 42 of the primary cyclone 40 and the foreign matter discharge port 52 of the secondary cyclone 50, (Arrow Fc3) and discharged from the foreign matter discharge port 63 to the outside of the pump (arrow Fc4).

The pump device 100 shown in Fig. 1 has a structure in which the suction side of the working fluid (the end plate 15 side) and the discharge side (The side of the pump housing 14) is disposed on the other side. The rotor 12 of the internal gear pump 10 is connected to the pump housing 14 on the end plate 15 side (suction side: lower side in Fig. 1) (The discharge side: upper side in Fig. 1).

The gear pump 10 of the pump device 100 is provided with the balance plate 7 on the side of the end plate 15 (suction side: lower side in Fig. 1) in order to suppress the step caused by the wear of the rotors 12, (See Fig. 3) are arranged. The balance plate 7 is made of a material with high hardness. 1, a balance plate mounting hole 15h is formed in a surface 15f of the end plate 15 which is in contact with the rotors 12 and 13, and the depth dimension of the balance plate mounting hole 15h is a balance plate 7). The balance plate 7 is attached to the balance plate mounting hole 15h.

As shown in Fig. 3, the balance plate 7 has a planar shape so that two semicircles 7oa (large semicircle) and 7ob (small semicircle) having different radii connect the bottom sides of each other. In the portion where the semicircles 7oa and 7ob are connected, the semicircles 7oa and 7ob are smoothly connected through the arc r having a small radial dimension. In Fig. 3, the center of curvature of the large semicircle 7oa is denoted by reference numeral C1, and the center of curvature of the small semicircle 7ob is denoted by C2. In Fig. 3, the two centers of curvature C1 and C2 are eccentric (offset) in the up-and-down direction in Fig.

O-ring grooves 71 and 72 are formed on the plane of the balance plate 7 and the O-ring grooves 71 and 72 are formed in an annular shape (ring shape) in a plan view and have a rectangular sectional shape. The center C3 of the O-ring groove 72 having a smaller radial dimension is located on a horizontal line Lh (one-dot chain line extending in the left-right direction in FIG. 3) passing through the center of curvature C1, And is positioned eccentrically to the left in Fig. 3 with respect to the center C1. A through hole 7i is formed in the inside of the small O-ring groove 72 in the radial direction. The through hole 7i is concentric with the O-ring groove 72 and the radius of the through hole 7i is smaller than the radius of curvature of the O-ring groove 72. [ The rotating shaft 5 (Fig. 1) is inserted into the through hole 7i.

Although not shown in Figs. 1 and 3, an O-ring (an elastic member resistant to a working fluid, for example, made of rubber) is inserted into the O-ring grooves 71 and 72. [ In the lower portion of the balance plate mounting hole 15h (see Fig. 1), two O-rings (not shown) form an area E2 surrounded by two O-ring grooves 71 and 72 3) is a sealed space (sealed space). In the sealing space (the area E2 surrounded by the O-ring grooves 71 and 72 in FIG. 3: the area hatched in FIG. 3), two through holes extending in the thickness direction of the balance plate 7 And a working fluid (a fluid indicated by an arrow F10R) penetrates through the through-hole 73. As shown in Fig. The working fluid which has entered the sealing space (the area E2 hatched in FIG. 3) is supplied with a pressing force for moving the balance plate 7 upward in FIG. 1 to apply the pressing force to the balance plate 7 To the rotor 12, 13 side. In addition, the two discharge pressure introduction holes 73 of the balance plate 7 are arranged so as not to be clogged by the inner rotor 13, even though one of them is clogged.

Reference numeral 74 in Fig. 3 is a pin hole for inserting a rotation preventing pin (not shown). A rotation prevention pin (not shown) prevents the balance plate 7 from rotating (the circulation by rotation of the rotation shaft 5). The pin hole 74 is a blind hole and is open at the side where the O-ring grooves 71 and 72 are formed.

1, a fixing plate 8 is disposed above the rotors 12 and 13 (on the opposite side of the balance plate 7) so as to contact the rotors 12 and 13. As shown in Fig. The stationary plate 8 is made of a material harder than the rotors 12 and 13. Further, it is preferable that the hardness is higher than that of the foreign matter which may be mixed in the cooling water. Fig. 5 shows details of the fixing plate 8. Fig. Fig. 5 shows that the suction port 82 and the discharge port 81 are formed in the stationary plate 8. However, the suction port 82 of the fixing plate 8 may not be formed. Further, when the suction port 82 of the fixed plate 8 is not formed, it is necessary that the sealing pressure relieving hole (not shown) is communicated with the suction chamber.

The fixing plate (the fixing plate in the first embodiment) shown in Fig. 5 is a pump of the type (Figs. 11 to 15) in which the suction side and the discharge side of the working fluid are arranged on the same side with respect to the rotation axis direction of the inner rotor And the discharge port 81 are formed in order to facilitate the commonization (component common use) with the fixed plate of the suction port 82 and the discharge port 81. Here, when the direction of rotation is different, the fixed plate of the pump (Figs. 11 to 15) is turned upside down. Reference numeral 84 in FIG. 5 denotes a mounting hole of the lock pin, and reference numeral 8i denotes an insertion hole of the rotary shaft 5.

The gap between the outer rotor 12 and the inner rotor 13 in the internal gear pump 10 continues from the suction side (lower side in Fig. 1) to the discharge side (upper side in Fig. 1). Therefore, the discharge pressure of the internal gear pump 10 is adjusted by the clearance (arrow F10R) between the outer rotor 12 and the inner rotor 13 (the arrow F10R) and the balance plate 7 with respect to the pump rotation axis direction (The bottom of the balance plate mounting hole 15h) of the balance plate 7 in Fig. 1 via the discharge pressure introducing hole 73 formed in the sealing space (the area hatching in Fig. 3 E2). Then, the balance plate 7 is pressed against the rotors 12 and 13 (upward in Fig. 1). The hatched area E1 in FIG. 2 indicates the area where the discharge pressure acts at the interval between the outer rotor 12 and the inner rotor 13 at a given moment. The discharge pressure of the hatched area E1 acts to press the balance plate 7 downward (in the direction away from the rotors 12 and 13) in Fig.

2 and 3,

Area of E1 <Area of E2

The pressure applied to the E2 side (below the balance plate 7 in Fig. 1) having a large area is higher than the pressure applied to the E1 side (above the balance plate 7 in Fig. 1) It becomes. As a result, the balance plate 7 is pressed to the discharge side (upper side of Fig. 1: the rotor 12, 13 side).

Here, if the force for pressing the balance plate 7 toward the discharge side (upper side in Fig. 1) is too strong, the pressure applied to the area E2 side will interfere with the rotation of the rotors 12, 13. On the other hand, if the force for pressing the balance plate 7 to the rotor 12, 13 side (upper side in Fig. 1) is too weak, the volume efficiency decreases due to wear of the end portions of the rotors 12, 13.

In the first embodiment, the position of the O-ring (that is, the position of the O-ring grooves 71 and 72) is determined so as not to cause a related problem. In other words, the position of the O-ring grooves 71 and 72 does not interfere with the rotation of the rotors 12 and 13 due to the pressure applied to the area E2 side and also the balance plate 7 rotates the rotors 12 and 13 (Upper side in Fig. 1) so as to prevent the volume efficiency from being lowered due to abrasion of the ends of the rotors 12, 13. The area of the region E2 is determined experimentally because the actual apparatus is influenced by the pressure gradient of the discharge pressure leaking from the region E1 to the outer periphery of the outer rotor 12 and the inner rotor 13.

3, the region E2 surrounded by the two O-ring grooves 71 and 72 is very small on the side of the suction port (the region indicated by the dotted line Li in FIG. 3) And the port 140 (the area Lo surrounded by the two-dot chain line in Fig. 3) is set to be large. This is because the pump discharge pressure is higher than the suction pressure so that the pump discharge side region Lo on which the discharge pressure of the balance plate 7 acts acts toward the rotors 12 and 13 with a large pressure. That is, the two O-ring grooves 71 and 72 press the pump discharge side region Lo, which is the region where the discharge pressure acts on the balance plate 7, to the rotor 12 and 13 side with a large pressure, 7 to equalize the amounts by which the rotors 12, 13 are pressed. On the other hand, the balance plate 7 has a shape that does not close the suction port 150 (Li in FIG. 3) and does not interfere with suction of the working fluid into the internal gear pump 10. In other words, a region not closed by the balance plate 7 on the suction side (lower side in Fig. 1) constitutes the suction port 150 of the internal gear pump 10. [

The balance plate 7 having a related structure pushes the suction side (lower side in Fig. 1) of the rotor 12, 13 to the discharge side (the upper side in Fig. 1) by the discharge pressure of the internal gear pump 10. As described above, since the balance plate 7 is made of a material with high hardness, it is not worn and remains flat. Therefore, the side surfaces of the rotors 12 and 13 which are pressed against the balance plate 7 are not worn in a concavo-convex shape. When the rotor 12, 13 is worn, the balance plate 7 moves toward the rotor 12, 13 side to reduce the clearance due to wear. Therefore, the volume efficiency of the internal gear pump 10 is improved.

As described above, the pressing force of the balance plate 7 against the suction side (lower side in Fig. 1) end face of the rotor 12, 13 is obtained from the discharge pressure of the internal gear pump 10. Therefore, when the internal gear pump 10 is started, the discharge pressure does not act on the balance plate. On the other hand, in the first embodiment, the O-ring having the cross-sectional diameter larger than the depth dimension of the O-ring grooves 71 and 72 is attached to the O-ring grooves 71 and 72, The elastic repulsive force Fr of the ring OR acts on the O-ring grooves 71 and 72 and the balance plate 7 is rotated by the elastic repulsive force Fr (upward in FIG. 4) 12, 13 (not shown in Fig. 4). In other words, in the first embodiment, for example, the initial pressure at which the balance plate 7 is pressed against the lower end surface of the rotor 12, 13 at startup is obtained by the elastic repulsive force Fr of the O-ring. Therefore, even when the discharge pressure of the internal gear pump 10 does not act on the balance plate 7, the balance plate 7 presses the lower end surface of the rotor 12, 13 shown in Fig. Here, since the balance plate 7 made of a material having high hardness is kept flat without being worn, the side surfaces of the rotors 12, 13 pressed by the balance plate 7 are not worn out in a concavo-convex shape , Formation of a step on the side surface of the rotor (12, 13) is suppressed. The portion where the rotor 12, 13 is worn moves toward the rotor 12, 13 side of the balance plate 7 to reduce the clearance due to abrasion. As a result, the volume efficiency of the internal gear pump 10 is improved.

Next, a second embodiment of the present invention will be described with reference to Fig. In Fig. 6, the pump device is shown at 100A in its entirety. In the first embodiment shown in Figs. 1 to 5, a stationary plate 8 (Fig. 5) is provided on the discharge side of the internal gear pump 10 (above the rotors 12 and 13 in Fig. 1). On the other hand, the fixing plate is not provided in the second embodiment of Fig. From the experiment of the inventor, it has been found that wear on the pump housing 14 side (on the discharge side: above the rotors 12 and 13 in Fig. 6) in the rotors 12 and 13 is not large. Therefore, it is possible to omit the fixing plate depending on the required specifications. Other configurations, actions and effects in the second embodiment of Fig. 6 are the same as those of the first embodiment of Figs. 1 to 5.

A third embodiment of the present invention will be described with reference to Figs. 7 to 9. Fig. In Fig. 7, the entire pump apparatus is indicated by reference numeral 100B. In the first and second embodiments shown in Figs. 1 to 6, as shown in Fig. 4, when the internal gear pump 10 is started, the balance plate 7 is moved to the initial position (For example, a force for pressing the balance plate 7 against the end face of the rotor 12, 13 at the time of starting: an upward force in Fig. 4) is obtained by the elastic repulsive force Fr of the O-ring . On the other hand, in the third embodiment shown in Figs. 7 to 9, due to the elastic repulsive force of the spring (coil spring) 9, not the elastic repulsion force of the O- 9), which presses the balance plate 7A against the end face of the rotor 12, 13 (pressing force toward the upper side in FIG. 9).

9 and Fig. 4, in the third embodiment, the positions of the O-ring grooves 71A, 72A or the O-ring OR of the balance plate 7A (see Fig. 9) , And is different from the second embodiment (see Fig. 4). 4 (first and second embodiments), the O-ring grooves 71, 72 or the O-ring OR of the balance plate 7 are arranged on the suction side of the balance plate 7 As shown in Fig. On the other hand, the O-ring grooves 71A and 72A or the O-ring OR of the balance plate 7A in the embodiment of Fig. 9 (third embodiment) have the balance plate 7A with respect to the rotational axis direction (Lower side in Fig. 9) and the discharge side (upper side in Fig. 9) of the balance plate 7A and the outer peripheral surface and the inner peripheral surface of the balance plate 7A. And the inner O-ring 72A faces a bushing (BS) which is fixedly coupled to the end plate 15.

As shown in Fig. 9 (and Fig. 7), a closed hole BH is formed on the suction side (lower side in Fig. 7) of the balance plate 7A, 9) are accommodated. The spring 9 is accommodated in a compressed state, and an elastic repulsive force acts in a direction in which the spring 9 extends. As a result, the balance plate 7A is pushed to the discharge side (upward in Figs. 7 and 9) by the elastic repulsive force of the spring 9 (the force generated by the extension of the spring 9) (For example, a force that presses the balance plate 7A toward the end faces of the rotors 12 and 13 at the time of starting) is obtained.

In Fig. 8, reference numeral 73A denotes a discharge pressure introducing hole 73, and reference numeral 74A denotes a mounting hole of the lock pin. 8 shows a contact position of two springs 9 set in the balance plate mounting hole 15h. The circle (dotted line) indicated by the symbol G in the right and left ends of Fig. In the third embodiment, the fixing plate 8 common to the first embodiment is used as the fixing plate.

Compared with the first embodiment and the second embodiment in which the initial pressure is obtained by the elastic repulsive force of the O-ring in the third embodiment in which the initial pressure at the start of the internal gear pump is obtained by the elastic repulsive force of the spring 9 (Amount of movement) of pressing the balance plate 7A against the elastic repulsive force can be set larger than in the first and second embodiments. Therefore, even if the abrasion amount of the rotors 12 and 13 is increased in the third embodiment, the balance plate 7A, which is made of a material having high hardness and is not worn and maintains a flat state, Is pressed. Therefore, formation of a step on the side surfaces of the rotors 12, 13 is suppressed. As the rotors 12 and 13 are worn out, the balance plate 7 moves toward the rotors 12 and 13 to reduce the clearance due to abrasion, thereby improving the volume efficiency. Other configurations and operation effects in the third embodiment shown in Figs. 7 to 9 are the same as those of the embodiments shown in Figs. 1 to 6.

Next, a fourth embodiment of the present invention will be described with reference to Fig. In Fig. 10, the entire pump apparatus is indicated by reference numeral 100C. In the third embodiment shown in Figs. 7 to 9, the stationary plate 8 (as shown in Fig. 5) is provided on the discharge side (upper side in Fig. 7) of the internal gear pump. On the other hand, in the fourth embodiment of Fig. 10, the fixing plate is not provided. Other configurations and operational effects in the fourth embodiment of Fig. 10 are similar to those of the third embodiment of Figs.

Next, a fifth embodiment of the present invention will be described with reference to Figs. 11 to 14. Fig. In Figure 11, the pump device is indicated generally at 200. 1 to 10 are all applied to a pumping apparatus of a type in which the suction side and the discharge side of the working fluid are disposed on the other side with respect to the rotation axis direction of the inner rotor 13 . On the other hand, in the fifth embodiment shown in Figs. 11 to 14, the present invention is applied to a pumping apparatus of the type in which the suction side and the discharge side of the working fluid are disposed on the same side with respect to the rotation axis direction of the inner rotor 213.

11 and 12, the pump device generally indicated by the reference numeral 200 includes a rotating shaft 205, a gear case 211, an outer rotor 212, an inner rotor 213, a pump housing 214, An end cap 215, and a support member 216. The support member 216, the pump housing 214, the gear case 211 and the end cap 215 are fixed to one by two through bolts B1 and a washer nut NW. The support member 216 and the pump housing 214 are fastened with the bolts B2 and the end cap 215 and the gear case 211 and the pump housing 214 are fastened with the bolts B3. The rotating shaft 205 is pivoted by a bearing (BG) opened to the pump housing 214 through a pump housing 214, an inner rotor 213 and a bearing (BS) opened to the end cap 215 . Here, the symbol K denotes a key for fixing the inner rotor 213 to the rotary shaft 205, the symbol SW denotes a thrust washer, and the symbol MS denotes an oil seal.

11, a balance plate mounting hole (not shown) for mounting the balance plate 207 is formed on a surface of the end cap 215 which is in contact with the rotors 212 and 213 (the left end surface of the end cap 215 in Fig. 11) (Blind holes) 215H are formed. On the other hand, a fixed plate mounting hole (concave portion) (not shown) for mounting the stationary plate 8 is provided on a surface of the pump housing 214 on the side contacting the rotors 212 and 213 (the right end surface of the pump housing 214 shown in Fig. 214H are formed.

12, the working fluid is sucked into the pump device 200 as indicated by a white arrow Fi and passes through the pump device 200 as indicated by a white arrow Fo, And is discharged from the apparatus 200.

In Fig. 12, reference character Pi denotes a suction port, and reference symbol Po denotes a discharge port. As shown in Fig. 13, in the fifth embodiment, the suction port Pi exists on the same side as the discharge port Po with respect to the rotation axis direction. Therefore, both the suction port Pi and the discharge port Po are shown on the same side in Fig. 11 and 12, the outer rotor 212 and the inner rotor 213 are rotated in the same direction, and the working fluid introduced from the suction port Pi passes through the gap between the toothed wheels of the rotors 212 and 213 And is discharged to the outside of the pump device 200 from the discharge port 214o of the pump housing 214 (Fig. 12) via the discharge port Po.

The balance plate 207 (Fig. 11) of the pump device 200 has a structure common to the balance plate 7 (Fig. 3) in the first embodiment. However, since the rotation direction of the rotor is different, the balance plate 207 has a shape symmetrical to the X-axis of Fig. 3 with respect to the balance plate of Fig. The balance plate 207 has an O-ring groove 207a having a large radial dimension and an O-ring groove 207b having a small radial dimension. O-rings are attached to the O-ring grooves 207a and 207b, respectively. A through hole (the same as the discharge pressure introduction hole 73 in FIG. 3) is formed in the balance plate 207, and a rotation preventing pin hole (same as the pin hole 74 in FIG. 3) is formed. The fixing plate 8 in the fifth embodiment also has a structure common to the fixing plate 8 of the first embodiment. However, when the direction of rotation of the rotor is different, the fixing plate 8 of the fifth embodiment has a structure in which the fixing plate 8 of the first embodiment is turned upside down.

In the fifth embodiment shown in Figs. 11 and 12, the balance plate 207 is pressed toward the rotors 212 and 213 similarly to the first embodiment shown in Figs. 1 to 5. The initial pressure is obtained by the elastic repulsive force of the O-ring. Other configurations and operation effects in the fifth embodiment of Figs. 11 and 12 are the same as those of the first embodiment of Figs. 1 to 5.

Next, a sixth embodiment of the present invention will be described with reference to Fig. The pump device shown in Fig. 13 is denoted by reference numeral 200A in its entirety. In the fifth embodiment shown in Figs. 11 and 12, the stationary plate 8 is provided on the drive source side (left side in Fig. 11) with respect to the rotation axis direction of the internal gear pump. On the other hand, in the sixth embodiment of Fig. 13, no fixing plate is provided. Other configurations, actions and effects in the sixth embodiment of Fig. 13 are the same as those of the fifth embodiment of the fifth embodiment of Figs.

Next, a seventh embodiment will be described with reference to Fig. In Fig. 14, the pump device is indicated by reference numeral 200B in its entirety. 11 to 13, when the discharge pressure does not act on the balance plate 207, for example, when the internal gear pump is started, the initial pressure at which the balance plate 207 is pushed to the drive source side (left in Fig. 11) Ring is obtained by the elastic repulsive force of the O-ring as in the embodiment and the second embodiment. On the other hand, in the seventh embodiment of Fig. 14, when the discharge pressure does not act on the balance plate 207A at the time of starting the internal gear pump, the balance plate 207A is moved to the initial pressure (left side in Fig. 14) Is obtained by the elastic repulsive force of the spring 209 as in the third and fourth embodiments.

The balance plate 207A (Fig. 14) of the pump device 200B has a structure common to the balance plate 7A (Figs. 8 and 9) in the third embodiment. However, since the direction of rotation of the rotor is different, the balance plate 207A has a shape symmetrical to the X-X axis in Fig. 8 with respect to the balance plate 7A in Fig. Even if the amount of wear of the rotors 212 and 213 is increased in the pump device 200B as well, the balance plate 207A, which is made of a material having high hardness and is not worn and maintains a flat state, The formation of the step on the side surfaces of the rotors 212 and 213 is suppressed. As the rotors 212 and 213 are worn out, the balance plate 207A moves toward the rotors 212 and 213 to reduce the clearance due to abrasion, thereby improving the volume efficiency. Other configurations and effects in the seventh embodiment of Fig. 14 are the same as those of the embodiments of Figs.

Next, an eighth embodiment of the present invention will be described with reference to Fig. In Fig. 15, the pump device is indicated at 200C in its entirety. In the seventh embodiment of Fig. 14, the stationary plate 8 is provided on the drive source side (left side in Fig. 14) with respect to the rotational axis direction. On the other hand, the fixing plate is not provided in the eighth embodiment of Fig. Other configuration, operation and effect in the eighth embodiment of Fig. 15 are the same as those of the seventh embodiment of Fig.

It is to be noted that the embodiments shown in the present invention are for illustrative purposes only and are not intended to limit the technical scope of the present invention. For example, in the illustrated embodiment, the balance plate is provided only on the suction side (right side in Fig. 1) and not on the discharge side (left side in Fig. 1). On the other hand, it is also possible to provide the balance plate only on the discharge side (the left side in Fig. 1). In this case, it is necessary to change the shape of the port from the embodiment.

5 ... rotation shaft
7 ... Balance plate
8 ... fixed plate
9 ... spring
10 ... internal gear pump
11 ... gear case
12 ... outer rotor
13 ... inner rotor
14 ... pump housing
15 ... end plate
20 ... suction plate
30 ... Cyclone relay impeller
40 ... primary cyclone
45 ... Cyclone case
50 ... Second cyclone
60 ... Impeller for foreign matter discharge

Claims (3)

A plate member is provided on an end face of the rotor and the plate member is formed of a material having a high hardness so that the suction port is not closed so that a through hole is formed And an O-ring groove having a continuous shape and containing an O-ring is formed. The method according to claim 1,
Characterized in that the O-ring groove is formed on the side of the plate-shaped member remote from the rotor, and the O-ring is mounted so as to have a prescribed tightening margin in the O-ring groove . The method according to claim 1,
Wherein a closed pore space is formed on the side opposite to the rotor of the plate member, and the elastic member is received in the pore hole space.

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