JPS6241992A - Pump - Google Patents

Abstract

PURPOSE:To bear both thrust and radial loads by constituting a fluid dynamic pressure bearing between both the sliding surfaces of an isolating plate with spiral grooves and a rotation receipt plate, and by retaining centering by the use of a core housed in a recess provided in such a way as fronting the center of the sliding surfaces. CONSTITUTION:A rotation receipt plate 23 in the form of a disc as a member equipped with a sliding surface of a flat plate provided for the rotary part of a pump is fixed by adhesion to the back of an impeller 13. The surface of an isolating plate 7 fronting this rotation receipt plate 23 has the same dia. as it and protrudes a little in the axial direction to constitute a sliding surface 25 with spiral grooves 24 except its central part, and a high viscosity lubricant 26 is previously incapsulated between these rotation receipt plate 23 and isolating plate 7, and the receipt plate 23 is attracted by said sliding surface of isolating plate 7. A hemispherical recess is formed in the center of the isolating plate 7 and rotation receipt plate 23, and a small ball 29 is accommodated in this recess. This arrangement bears well thrust and radial loads, prevents wear because of slurry etc. and enhances durability.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] "Industrial Application Field" The present invention relates to a magnet pump that handles various corrosive liquids and the like.

``Prior Art'' Figure 5 is a vertical sectional view of a conventional magnet pump. Drive-side magnets y, in which permanent magnets with different polarities are arranged alternately, are fixed on the end surface circumference of a disk 3 made of magnetic insulating material fixed to the end of the motor shaft of the motor. The lower bracket j of the motor and the pump casing ring are closely pierced through a separator plate 7 made of a non-magnetic material and fixed with bolts and nuts t.

The pump casing 6 is attached to the suction port of the pump casing 6.
A boss // is provided at the center of a radial arm 10 provided integrally with the arm i.

The space between them is a suction passage. A pump shaft concentric with the motor shaft is fixed to the boss //, and a bearing metal /V with a flange press-fitted into the impeller /3 is slidably fitted to the pump shaft /2. /! is a liner ring that is press-fitted into the pump casing 61 and fits with the outer periphery of the suction portion of the impeller with a small gap to form a water seal.

On the motor side end of the impeller /3, an impeller side magnet (A) is dug and fixed, which is opposite to the drive side magnet via a separating plate and has permanent magnets with different polarities arranged at intersections. .

The strainer is held by covering the outer periphery of the pump casing 6 by a plywood plate that is fitted into the legs of the pump casing and is attached to the pump casing Iζ by bolts (not shown).

When the motor / is energized, the motor IkII, the disc 3, and the drive side magnet rotate, and due to the magnetic force I of the drive side magnet, the impeller side magnet ) /A is driven, and the impeller /A is driven.
3 rotates on the pump shaft/2, and the liquid flows through the strainer/9,
It passes through the suction port 9, enters the pump casing, is sucked into the impeller 13, increases the pressure, and is discharged at a discharge rate of 0.2/. A portion of the liquid flows from the high pressure side between the impeller side magnet 6 and the separator plate 7 toward the center and circulates from the balance pole 2- to the low pressure side to balance the pump thrust. With this configuration, the motor shaft and pump shaft are independent, and there is no shaft sealing device between the motor and pump, and the handled liquid is separated by a separator between the motor and pump, and corrosive liquid etc. can damage the motor. It has no impact.

[Problem to be solved by the invention J The above-mentioned pumps are used for all kinds of corrosive liquids, but in the case of corrosive liquids, if there are precipitates or crystallized substances,
These solid substances caused significant wear and tear on the end face and cylindrical face of the bearing metal/41, resulting in insufficient durability. For this reason,
Ceramic materials with strong corrosion and wear resistance are increasingly being used as materials for these bearing metals. However, bearings made of hard materials have a high starting torque value, which causes unevenness and local damage. In addition, conventional bearings have a high coefficient of friction and are not durable enough due to slurry contamination.

Some magnet pumps have a structure in which sliding parts such as the bearing metal 4' can be easily replaced in anticipation of wear.

In addition, in conventional radial bearings, the clearance between the bearing and the shaft is at least 0 μm or more, and the vibration of the impeller due to this is also a cause of increased wear in other parts (
For example, in a magnet pump with a worn part of the liner ring 15, the drive side magnet 1 and the impeller side magnet 1 attract each other, and the problem is how to efficiently transmit shaft torque, so it is necessary to keep both magnets as close as possible. There is. At present, due to the problem of bearing wear as described above, the separator plate 7 is
There is a gap of several lengths between the impeller side magnet) and A. Additionally, slurry and the like get caught in these gaps, causing trouble.

Magnetic pumps cannot have a single suction port unlike normal pumps in which the motor shaft is extended and an impeller is attached as the pump shaft, increasing suction resistance, and the shape of the pump casing is complicated, making machining difficult.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems in a magnet pump in which the pump is magnetically connected to a motor, and to provide an efficient magnet pump that is free from problems caused by wear and tear of worn parts due to slurry or the like.

[Structure of the invention]

``Means for Solving the Problems-j'' The present invention provides a pump in which a pump and a motor are sealed and coupled via a separator, and a pump rotating part and a motor shaft are connected non-contact by a magnetic joint. A sliding surface with a spiral groove provided between the fixed member constituting the chamber and the rotating part of the pump and a sliding surface of a flat plate are slid, and the center of both sliding surfaces is opposed to a member having both sliding surfaces. This pump is characterized in that a thrust bearing is constructed in which a recess is provided in each of the recesses, and a core material is accommodated across both recesses.

"Function" A fluid dynamic pressure bearing is constructed between a sliding surface provided with a spiral groove and a flat plate sliding surface, and a recess is provided at the center of both sliding surfaces facing the member provided with the sliding surface. The center is maintained by the core material housed in the center, and it can withstand thrust loads and radial loads.

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

FIG. 1 is a longitudinal sectional view. The motor section is the same as that described for the conventional example, and the parts of the pump section that are the same as those of the conventional example are given only the reference numerals and the explanation thereof will be omitted.

The pump casing differs from the conventional example in that the suction port is open to the center. feather p car/
J is not provided with a balance hole, and a disc rotary receiving plate 3 is adhesively fixed to the back surface of the impeller 3 as a member having a flat sliding surface for the pump rotating part. This rotating plate,
The surface of the separating plate facing 23 has the same diameter as the rotary receiving plate 23 and protrudes a small amount in the axial direction, and as shown in the bottom view in Fig. A small amount of high-viscosity lubricant λ6 is added in advance between the rotating receiving plate 3 and the separating plate 7, and the rotating receiving plate 3 is connected to the sliding surface of the separating plate. ! is adsorbed to. Separation plate 7 and rotating receiver □' plate. As shown in Figure 3, which is a partially enlarged view of Figure 1, in the center of 3, there is a hemispherical recess, 2? , 2g are provided, and a small ball 9 is fitted into the recess. Small ball 29 and recess, 2? , 2g is a dimension in which the separator plate 7 and the rotary receiving plate 23 are in solid contact with each other, or there is a slight gap between them.

In the above, the isolation plate is made of β-crystalline silicon carbide sia, and the spiral groove 2 is formed by overlapping a photomask and shot blasting, and the depth is 3 to 5 μm.
It is. The sliding surface j has a mirror finish with a flatness of /μm. The rotating receiving plate-J is made of silicon carbide 810, stainless steel, or cast iron, and its sliding surface is mirror-finished to a flatness/μml. Small ball 2? is made of acicular crystals of silicon carbide β-8iO or bearing steel. High viscosity lubricant 26 is fluorine oil.

The diameter of the rotary receiving plate 23 is b o mm IJ meters, and the spiral groove 2q penetrates to the outer circumferential side and the depth is /θμm1
Small sphere, 2 small spheres 29/, sgmi I) is the size of a meter. The gap between the isolation plate 7 and the impeller side magnet/B is io
- tested at goμm.

In the pump of FIG. 1, when the motor is energized in the clockwise direction (FIG. 2) when viewed from below, the impeller side magnet 6 rotates in the same direction, and the rotary receiving plate 3 rotates together. The high viscosity lubricant roller turns into a spiral groove as it rotates clockwise when viewed from the bottom of the rotary receiving plate 3! Due to the action of +, dynamic pressure is generated toward the center, a fluid dynamic pressure bearing is formed, and the thrust toward the motor side of the impeller 13 is supported.

When we measured the thrust load capacity between the separator plate 7 and the rotary receiving plate 23 described above, it was found that the thrust load capacity was 20θKff in a state where no dynamic pressure was generated at the time of startup, and that the thrust load capacity was 20θKff and had a spiral groove made of a conventionally known metal material. The thrust bearing, which used to be only a few Kff and was not practical, has become sufficient for practical use, and the rotational speed is 7000 r, pJn.

When dynamic pressure was generated, the load capacity was jOθ0K4f.

At this rotational speed, the adsorption force was 1/100 f, and the impeller 13 did not separate from the separator plate 7 side. Also, for radial loads, the recess 27. ig and small ball J? The impeller/3 was sufficiently supported by the sliding bearing, and no displacement in the radial direction of the impeller/3 was observed.

Slurry was pumped using the above pump, but no slurry was caught between the sliding surfaces of the thrust bearing.

Figure 3 is a longitudinal sectional view of another embodiment of the thrust bearing configuration.

In the above embodiment, a spiral groove was provided directly on the separator plate 7 to constitute a dynamic pressure thrust bearing. Fix by fitting and gluing, and attach the rotary receiving plate to the bearing plate 3/, 23
Alternatively, the surface may be rubbed.

In addition, in each of the above embodiments, a spiral groove is provided on the sliding surface of the rotary receiving plate λ3, and the separating plate or bearing plate 31 is provided oppositely.
The sliding surface may be flat.

As described above, in each of the embodiments, the rotation direction is limited to one direction in which dynamic pressure is generated in the fluid dynamic pressure thrust bearing.

FIG. 5 is a longitudinal cross-sectional view of an embodiment in which a single fluid dynamic pressure thrust bearing is constructed so as to be able to freely rotate in forward and reverse directions, and is the same as FIG. 7 except for the bearing portion. As shown in Figure 1, which is a bottom view of the three bearing plates, bearing plate No. 31 has spiral grooves and two grooves in the same direction when viewed from the same side on both sides, and a separating plate and a rotary receiving plate. 3 is a flat sliding surface that slides on the three bearing plates. A small ball 9 is housed in a concave portion having a hemispherical diameter between the centers of the bearing plate 3, the separating plate, and the rotary receiving plate 3. The gap between the small ball 9 and the recess, and the gap between the sliding surface of the bearing plate 3 and the sliding surface of the separating plate and the rotating receiving plate 3 are the same as in a unidirectional rotating fluid dynamic thrust bearing, High viscosity lubricant-6 is sealed in these gaps. When the rotary receiving plate 3 rotates together with the impeller-side magnet 16 in the counterclockwise direction when viewed from below in FIG. configured to carry thrust loads. On the upper surface of the 3 bearing plates, when the 3 bearing plates are about to be biased clockwise, the high viscosity lubricant 6 in the spiral groove turns to the outer periphery, and vacuum pressure is generated in the center, causing the isolation plate to Adsorb. When the rotary receiving plate 3 rotates clockwise when viewed from below, the high viscosity lubricant rollers in the spiral groove on the lower surface of the bearing plate 3 move toward the outer periphery, so the center is vacuum-adsorbed and the bearing plate 3 rotates. It rotates together with the receiving plate 3. The rotation of the three bearing plates in the direction of the hour hand creates a spiral groove on the top surface of the three bearing plates! Due to the action of 4N, the high viscosity lubricant rollers move toward the center and act as fluid dynamic pressure bearings, supporting the thrust load.

FIG. 7 is a longitudinal sectional view showing another embodiment of the present invention. In this embodiment, the previously mentioned fluid dynamic pressure thrust bearings 33 and 344 are provided between the isolation plate and the impeller 73, and between the impeller 13 and the boss//interface of the suction port of the bomb casing. The bearings y, y, and ye are configured to rotate in one direction or rotate in forward and reverse directions, although the configuration is not shown, and a small ball is accommodated across a recessed portion at the center of each sliding surface. In this way, as in the case of the configuration shown in FIG. 1, it is necessary to support the bending moment based on the radial load by resisting the movement of the rotating receiving plate 3 of the thrust bearing away from the sliding surface 23 of the separator plate 7. Since the radial load can be carried by the small balls at both ends of the impeller 13, it is suitable when the radial load is large.

〔Effect of the invention〕

The present invention provides a pump ζ in which a pump and a motor are sealed together via a separator, and a pump rotation part and a motor shaft are connected without contact by a magnetic joint, and a fixed member constituting a pump chamber and a pump A sliding surface provided with a spiral groove provided between the rotating parts and a sliding surface of a flat plate are slid, and a recess is provided in the center of both sliding surfaces facing the member provided with both sliding surfaces, respectively,
Since the pump is characterized by comprising a thrust bearing that accommodates a core material across both of the concave portions, the axial distance between the magnetic joint between the pump rotating portion and the motor shaft is shortened, and the power transmission efficiency is improved. It can withstand large thrust loads.

When the separator is provided with a spiral groove, the separator is preferably made of a non-magnetic ceramic material and has an extremely large thrust load capacity. Forward and reverse rotation is possible by rubbing a disc with spiral grooves in opposite directions on both sides once so that both sides come in contact with the sliding surfaces provided on each of the fixing members that constitute the pump rotating part and the pump chamber. If a high viscosity lubricant is applied between the sliding surface with spiral grooves and the sliding surface, the impeller will not be dragged toward the suction port in the coaxial direction when the impeller is stationary or when operating. The small ball in the center prevents movement in the radial direction. When the thrust bearings are arranged at both ends of the impeller in the axial direction, the impeller can withstand large thrust loads in both directions, and can also withstand large radial loads.

The thickness of the lubricating oil film on a thrust bearing is under load/,! It is extremely thin, on the order of μm, and the absolute value of the difference between the liquid thickness under no load and under load is small. Since the gap is extremely small (10-go μm), the solid content of the slurry will not clog between the impeller and the separator.
A phenomenon in which the rotation of the impeller is locked no longer occurs.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view of an embodiment of the present invention, FIG. 1 is a bottom view showing the center of the separator, FIG. 3 is a partially enlarged view of FIG. 1, and FIG. 5 is a longitudinal sectional view of another embodiment of the present invention, FIG. 6 is a bottom view of the bearing plate of FIG. 5, and FIG. 7 is a longitudinal sectional view of yet another embodiment of the present invention. FIG. 5 is a longitudinal sectional view of a conventional example. l...Motor Motor shaft 3.0 disk V...Drive side magnet Lower bracket Meng...Pump casing 7.Separator plate T...Bolt nut D...Suction port 10.Arm /l ...Boss lλ...Pump shaft /3--Impeller /4'...Bearing metal /j@-
Liner ring /6... Impeller side magnet /11
11 Legs /L・・Bed plate /De-working number strainer @・Discharge port, 2・・Balance hole 23・・Rotary receiving plate
Burnt: Spiral groove Jj: Sliding surface 26, High viscosity lubricant λ, Jf: Recessed portion Burnt: 0 small ball 31,
3-piece threat/bearing plate:',? ,? ,,I evening...
Fluid dynamic thrust bearing.

Claims (1)

[Claims] 1. A fixed member forming a pump chamber in a pump in which a pump and a motor are sealed and coupled via a separator, and a pump rotating part and a motor shaft are connected without contact by a magnetic joint. A sliding surface provided with a spiral groove provided between the pump rotating part and a sliding surface of a flat plate is slid, and a recess is provided in the center of both sliding surfaces facing the member provided with both sliding surfaces. . A pump comprising a thrust bearing that accommodates a core material across both of the recesses. 2. The pump according to claim 1, wherein the member is made of silicon carbide (SiC) and has a sliding surface with spiral grooves. 3. One side of a disk having a sliding surface with spiral grooves in opposite directions on both sides is in contact with the sliding surface provided on the fixed member constituting the pump chamber, and the other side of the disk is connected to the pump rotating part. The pump according to claim 1 or 2, wherein the pump is in contact with a sliding surface provided on the pump. 4. The pump according to claim 1 or 2, wherein a sliding surface with a spiral groove is formed on a member adhesively fixed to the separator. 5. Any one of claims 1 to 4, in which a highly viscous lubricant insoluble in water is applied in advance between the sliding surface provided with spiral grooves and the sliding surface. Pumps listed in. 6. Any one of claims 1, 2, 3, and 5, wherein a thrust bearing is constructed between both sides of the impeller in the axial direction, the center of the pump casing on the suction port side, and the separator plate. Pumps listed in.