JPH06257574A - Rotary pump - Google Patents

Abstract

PURPOSE:To readily and quickly replace sealing members at low cost by providing a tightening wedge for each sealing member in a means for locking the sealing members onto the conveying blades of a rotor, and using a controlling element which can be operated from the end face of each sealing member. CONSTITUTION:A rotary pump 1 has rotors 2, 2 ' provided on respective shafts 20, 20' in a pump casing 10 in such a manner as to be rotatable in opposite directions while in engagement with each other. Each of the rotors 2, 2' is provided with a plurality of conveying blades 21 and a sealing member 3 having a pad 31 thereon is replaceably provided at the outer end portion of each conveying blade 21. Each sealing member 3 is axially movable on the conveying blades 21 and can be locked onto the conveying blades 21 by locking means. In this case, the locking means is provided with at least one tightening wedge 33 for each sealing member 3. The tightening wedge 33 can be displaced by a control member 35 which can be operated from the end face of each sealing member 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary pump, in particular for conveying a fluid containing a solid substance, and more particularly to a pump casing having an elliptical cross section and an axial shaft in the pump casing. A pair of rotors that are arranged in mesh with each other and can be driven to rotate in opposite directions, each rotor having a plurality of carrier blades, and a plastic pad is provided at an outer end of the carrier blades in the radial direction. Alternatively, at least one replaceable seal member provided with a rubber pad is provided, which seal member, when the rotor rotates, rotates in close contact with the inner surface of the wall of the pump casing and the respective partner rotor, However, by connecting the groove and the tongue to a rotary pump that can be moved in the axial direction on the carrier blade and can be locked on the carrier blade by the locking means. To.

[0002]

2. Description of the Prior Art A rotary pump of this kind is known from DE-A 180 7 392. In the configuration of this known rotary pump, the seal member is formed of a plastic member inserted and attached to the carrier blade. In this case, the bottom portion of the plastic member is inserted into the corresponding guide provided on the conveying blade from the end face side of the conveying blade. To prevent the sealing member from moving in its longitudinal direction, flat discs or plates are attached to both end faces of the rotor. These flat discs or plates also cover the ends of the sealing member. Also, the flat discs or plates on the end face side are made of the same material as the sealing member and are therefore elastic and relatively flexible.

A drawback of the known rotary pump described above is that the sealing member cannot be reliably locked to the carrier blade. This is because the end-side disc or plate used for locking can only accept a small amount of force and does not guarantee a reliable and slip-free fixing of the sealing member.

Another rotary pump is known from DE-A-3707722. In one embodiment of this known rotary pump, a groove / tongue connection is provided between the carrier blade and the seal member. In this case, an undercut protruding dovetail tongue is provided at the outer end of the carrier blade, and a seal member is attached on the dovetail tongue. In order to prevent relative movement between the seal member and the carrier blade in the transition region between them, the seal member is
It is surface-bonded to the metal plate on the carrier blade side. The metal plate and the lower portion of the seal member are formed with dovetail grooves that fit accurately against the tongue. Locking of the seal member and the metal plate on the conveying blade is performed only by the frictional force, but if the frictional force is appropriately selected and is sufficiently large, reliable fixing can be obtained only by this frictional force. However, when the worn seal member is replaced with a new seal member, if the frictional force is large, it becomes very difficult to remove the worn seal member.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to quickly and easily replace a seal member during maintenance work.
The object is to provide the rotary pump mentioned at the beginning which can be manufactured at low cost.

[0006]

According to the present invention, in order to solve the above-mentioned problems, the locking means has at least one tightening wedge provided for each seal member, and the tightening wedge is provided from the end surface side of the seal member. It is characterized by being displaceable by an operable operating element.

According to the second aspect of the present invention, each of the carrier blades is provided with an undercut groove, and each of the seal members is
Each of the clamping wedges has a tongue shaped to fit in the groove, and each clamping wedge is configured as part of the tongue.

According to claim 3, the tightening wedge is configured as a loose member which is aligned with the remaining tongue and abuts the adjacent portion of the remaining tongue via a pair of bevels. The bevels are oriented such that the clamping force is generated in the radial direction of the rotor.

According to claim 4, the operating element for the tightening wedge is formed by a bolt which is axially guided through the sealing member, the bolt being screwed into a screw hole provided in the tightening wedge. It is possible. In this case, the head of the bolt for applying a suitable operating tool can be arranged so as to be located on the end surface of the sealing member. Further, the head of the bolt may be settled in the seal member.

According to claim 5, the groove is a T-shaped groove or a dovetail groove.

According to the sixth aspect, the tongue is configured to be shorter than the groove at the end located on the end face of the rotor,
The free part of the groove can be fitted with an elastic plug member shaped to correspond to the cross section of the groove.

According to claim 7, the pump casing is
A removable flat cover is provided on the end face opposite to the drive unit, and the free end faces of both rotors are located in front of the cover when the covers are attached.

According to the eighth aspect, the seal member has a core made of metal, and the plastic pad or the rubber pad can be attached to the core by injection molding or vulcanization.

According to the ninth aspect, the tongue is formed integrally with the metal core portion.

According to the tenth aspect, the tongue is detachably connected to the metal core as a separate member, and is preferably screwed to the metal core.

[0016]

According to the first aspect, the locking force generated by the locking means can be changed as required. For example, the clamping wedge can be loosened for the attachment and removal of one sealing member. Therefore, the seal member can be attached and detached without requiring a large force. Take the clamping wedge to the clamping position in order to secure the seal member in position on the carrier blade. As a result, the seal member is prevented from being inadvertently displaced on the conveying blade to cause a problem. Furthermore, since the operating element for displacing the tightening wedge can be operated from the end surface side of the seal member,
It can be operated without any trouble. Therefore, it suffices to provide an opening on the end face side of the pump casing for attaching and detaching the plurality of seal members. This reduces the time and effort required to maintain and repair the rotary pump.

According to the second aspect of the present invention, the carrier blade that operates in the pump for a relatively long period has no moving parts. Movable parts are provided on the sealing element which must be replaced from time to time due to forced wear.
Therefore, the tightening wedge does not become stuck due to the corrosion caused by the aggressive carrier fluid.

According to the third aspect, a special mounting space is not required for the locking means, and it is possible to provide the sealing member in a small space at the end.

According to the fourth aspect, the operation of the operation element becomes very simple. Allowing the bolt head to settle into the seal member protects the bolt head from aggressive liquids and, optionally, solid particles carried with the liquid.

According to the fifth aspect, the groove can be formed relatively easily, and on the other hand, it is possible to withstand a mechanical high load.

According to the sixth aspect, the aggressive liquid carried by the pump does not enter the groove.

According to claim 7, the operator can easily approach the end face side of the rotor. Also, the structure of the pump casing is simplified. This facilitates manufacturing of the pump casing and reduces manufacturing costs. The opening on the end face side is completely used for replacement of the seal member.

According to the eighth aspect, the plastic pad or the rubber pad and the metal core are closely coupled.
Also, the volume of the plastic or rubber pad is limited so that damage caused by creep and shearing action of the plastic or rubber pad is avoided.

According to the ninth aspect, the seal member can be easily manufactured, and high stability can be obtained.

According to the tenth aspect, even if the plastic pad or the rubber pad of the sealing member is worn, the tongue can be tightened and the wedge can be continuously used. If the plastic pad or rubber pad of the seal member wears,
It is sufficient to replace the metal core with the plastic or rubber pad.

[0026]

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

In the embodiment shown in FIG. 1, the rotary pump 1 has a pump casing 10. The pump casing 10 includes a supply connection member 11 and a discharge connection member 12, and two rotors 2 and 2'arranged inside the pump casing 10 having an elliptical cross section. In this embodiment, the two rotors 2, 2'are of the three-blade type, i.e. each rotor 2 or 2'has three carrier blades 21. The rotors 2 and 2'are supported by two shafts 20 and 20 'which are parallel to each other and can be rotationally driven in opposite directions. In FIG. 1, the directions of rotation are the axes 20, 2
It is shown by the arrow marked on the end face of 0 '. In FIG. 1, the pump casing 10 is illustrated with the end face side opened, but the pump casing 10 is provided with a cover flange 14. A flat casing cover (not shown in FIG. 1) can be tightly attached and fixed to the cover flange 14. A drive device 13 is provided on the opposite side of the rotary pump 1 from the pump casing 10. Drive device 1
3 is an electric motor provided with a transmission device, for example. Neither the transmission nor the electric motor is shown in the figure.

As described above, each of the rotors 2 and 2'has three carrier blades 21. The carrier blade 21 carries the seal member 3 on the outer side in the radial direction. Groove / tongue connecting means is provided to connect the seal member 3 and the conveying blade 21. In FIG. 1, a groove 22 having a T-shaped cross section can be seen in the upper conveying blade 21 of the upper rotor 2. The groove 22 extends in the longitudinal direction of the rotor 2 so as to penetrate the conveying blade 21. The seal member 3 shown in FIG. 1 as being taken out from the groove 22 has a tongue 32 formed on the lower surface thereof so as to match the shape of the groove 22. Tone 32
This allows the seal member 3 to be pushed in in the axial direction.
On the contrary, the seal member 3 can be taken out in the axial direction. The seal member 3 is a pump casing 10 of the pump 1.
Of the plastic pad or the rubber pad 31 in the region of contact with the inner surface of the wall of the
Is equipped with. Plastic pad or rubber pad 3
1 is connected to the remaining metal parts of the sealing member 3 in a suitable manner. The tongue 32 of the sealing element 3 likewise consists of metal, preferably steel. In order to lock the seal member 3 on the carrier blade 21 of the rotor 2, the tongue 32 is
It has a tongue configured as a clamping wedge 33. This tightening wedge 33 can be moved axially by means of a bolt 35 guided by a tongue 32. By rotating the bolt 35 (the head of the bolt 35 is located on the end surface of the seal member 3),
It is possible to adjust the position of the tightening wedge 33 between a tightening release position that allows the seal member 3 to be displaced and a tightening position that fixes the seal member 3 on the conveyance blade 21. The erosive liquid carried by the pump is in the groove 22.
The tongue 32 of the sealing member 3 is constructed to be somewhat shorter than the groove 22 provided in the conveying blade 21 in order to prevent the penetration of the inside of the head and the area of the head of the bolt 35. Groove 22
, The remaining area not occupied by tongue 32
Used to house the elastic plug member 36. Plug member 3
6 is adapted to the cross-sectional shape of the groove 22 and can be pushed into the groove 22 to seal the groove 22. In order to expose the head of the bolt 35 for adjusting the position of the tightening wedge 33, the plug member 36 may be lightly pulled out to the outside.

FIG. 2 shows the rotary pump 1 shown in FIG.
The rotor 2 is taken out of the figure and illustrated. Also in this case, the sealing member 3 is shown in the removed state. As can be seen from FIG. 2, the length of each seal member 3 is selected so that the two seal members 3 are connected in series and match the length of the carrier blades 21 of the rotor 2. Therefore, if only a portion of the rotor 2 is damaged in the area of one sealing member 3, then one sealing member 3 which only extends over half the length of the rotor 2 needs to be replaced. This reduces the consumption of replacement parts. The seal members 3 arranged in series are completely the same, and the individual seal members 3 can be attached at any arbitrary positions. Since the seal member 3 is configured like a unit system in this way, if the rotor is smaller or larger than the illustrated rotor 2, one or two, or three, depending on the size of the rotor 2 is shown. It is also possible to equip each conveying blade 21 with the sealing member 3 of FIG.

From FIG. 2 in which the sealing member 3 is taken out and shown in the drawing, it can be clearly seen that the tightening wedge 33 is provided on the lower surface of the sealing member 3. The tightening wedge 33 is provided with a tongue 32 in FIG. 2 via a pair of inclined surfaces 34 and 34 '.
Abuts on the right side of the. By rotating the bolt 35, the tightening wedge 33 is displaced along the inclined surfaces 34 and 34 ', and thus moves upward or downward. Therefore, if the seal member 3 is arranged in the groove 22 of the carrier blade 21 of the rotor 2, it is possible to generate or release a desired tightening force.

When a plurality of sealing members 3 are arranged in series on one conveying blade 21, the rear sealing member, that is, FIG.
When it is necessary to replace the left seal member 3 in,
First, the front seal member 3 is removed. As a result, the bolt 35 on the end surface of the rear seal member 3 can be operated. The seal member 3 is attached in the reverse order.

FIG. 3 shows a part of a modification of the seal member 3 shown in FIGS. 1 and 2. The sealing member 3 is composed of a core portion 30 made of metal and a plastic pad or a rubber pad 31 attached to the core portion 30 by injection molding or vulcanization. The contour of the metallic core 30 allows a particularly firm and permanent connection between the core 30 and the plastic or rubber pad 31.

FIG. 4 is a vertical sectional view of the entire seal member 3. In this longitudinal section, from top to bottom, firstly a plastic or rubber pad 31, a metallic core 30, and a tongue 32 can be seen. Further, as can be seen from FIG. 4, the plastic pad or the rubber pad 31 is integrally formed and protrudes beyond the end face of the metal core portion 30. As a result, the pump casing 1 also has an end face side.
A sufficient sealing effect between 0 and the sealing member 3 is achieved.

Also in this embodiment, the cross section of the tongue 32 is T-shaped. In this case, the T-transverse part is facing down.
The narrow portion of the T-shaped tongue 32 is engaged with a recess provided in the lower surface of the metallic core portion 30 and is removably screwed to the core portion 30 by two bolts 30 ″.

The part of the tongue 32 on the left side in FIG. 4 is
It is configured as a tightening wedge 33. The tightening wedge 33 is in line with the rest of the tongue 32 in the final locked position shown in FIG. Tone 3
The second stationary part has a slope 34 at its left end. The tightening wedge 33 has a slope 34 ′ facing the slope 34 at the right end thereof. A screw hole 33 'extends through the tightening wedge 33. The bolt 35 can be screwed into the screw hole 33 '. The bolt 35 is in contact with the right side surface, that is, the end surface of the tongue 32 by its head, and the hole 3 provided in the tongue 32 so as to extend in the axial direction.
It penetrates 5 '. The size of the hole 35 'is 3 bolts.
5 has sufficient clearance above and below to allow the clamping wedge 33 to move along the slopes 34, 34 'relative to the rest of the tongue 32. Another hole 32 'extends vertically through the tongue 32 relative to the hole 35', and by inserting a bolt 30 '' from the hole 32 'into a threaded hole 30' communicating therewith, the tongue 32 ' Metal core 30 of the seal member 3
And can be linked.

[0036]

In the rotary pump according to the present invention, especially during the maintenance work, the replacement of the seal member can be performed quickly, easily and inexpensively.

[Brief description of drawings]

FIG. 1 is a perspective view of a rotary pump according to the present invention shown with a pump casing opened and a seal member taken out.

FIG. 2 is a perspective view of the rotor shown with the seal member removed.

FIG. 3 is a partial cross-sectional view of a modified example of the seal member.

4 is a vertical cross-sectional view of the entire seal member of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 rotary pump 2,2 'rotor 3 sealing member 10 pump casing 20,20' shaft 21 conveying blade 31 plastic pad or rubber pad 33 tightening wedge

Claims (10)

[Claims] 1. A pump casing (10) having an elliptical cross section, and a shaft (20, 20 ') arranged in the pump casing (10), meshing with each other and rotatable in opposite directions to each other. A pair of rotors (2,2 ')
And the rotors (2, 2 ') each have a plurality of carrier blades (21), and a plastic pad or a rubber pad (3) is provided at the radially outer end of the carrier blades (21).
At least one replaceable seal member (3) with 1) is provided, which seal member (3) is respectively in contact with the inner surface of the wall of the pump casing (10) during rotation of the rotor (2, 2 '). It rotates in close contact with the mating rotor (2 ', 2), the sealing member (3) being axially movable on the carrier blade (21) by the connection of the groove and the tongue, and In a rotary pump lockable on a conveying blade (21) by a locking means, the locking means has at least one tightening wedge (33) provided for each sealing member (3), and the tightening wedge (33) Can be displaced by an operating element operable from the end surface side of the seal member. 2. Conveyor vanes (21) each comprising an undercut groove (22) and a respective sealing member (3) shaped tongue (3) to fit into said groove (22).
Rotary pump according to claim 1, characterized in that it has a 2) and that the clamping wedges (33) are each configured as part of a tongue (32). 3. A clamping wedge (33) is aligned with the remaining tongue (32) and abuts an adjacent portion of the remaining tongue (32) via a pair of bevels (34, 34 '). The rotary pump according to claim 2, wherein the rotary pump is configured as a loose member. 4. The operating element for the clamping wedge (33) is formed by a bolt (35) axially guided through the sealing member (3), said bolt (3)
Rotary pump according to any one of claims 1 to 3, characterized in that 5) can be screwed into a screw hole (33 ') provided in the tightening wedge (33). 5. The rotary pump according to claim 2, wherein the groove (22) is a T-shaped groove or a dovetail groove. 6. The tongue (32) is designed to be shorter than the groove (22) at the end located on the end face of the rotor (2, 2 ′), the free part of the groove (22). 6. An elastic plug member (36) shaped to correspond to the cross-section of the groove (22) can be inserted into the slot according to claim 1. Rotary pump. 7. A pump casing (10) has a removable flat cover on its end face opposite to the drive device (13), and both rotors (front) of the cover in the installed state of the cover (10). Rotary pump according to any one of claims 1 to 6, characterized in that the free end faces 2,2 ') are located. 8. The seal member (3) is made of a metal core (3).
0), and the plastic pad or the rubber pad (31) can be attached to the core part (30) by injection molding or vulcanization treatment, any one of claims 1 to 7. Rotary pump described in one. 9. Rotary pump according to claim 8, characterized in that the tongue (32) is formed integrally with the metallic core (30). 10. The tongue (32) is detachably connected to the metal core (30) as a separate member and is preferably screwed to the metal core (30). The rotary pump according to claim 8.