TW201510372A - Rotary-vane vacuum pump - Google Patents

Abstract

This invention relates to a rotary vane vacuum pump having a drive motor (1, 17) co-operating with a chamber for vacuum vane pumping (2) in which all the surfaces of pump visible from above are set up in such a way that they are devoid of elements susceptible to retaining liquids or solids. The drive motor (1) can be in particular an air-cooled asynchronous motor or a water-cooled asynchronous motor having a housing, forming with the cylinder (18) a space in which a coolant can circulate.

Description

Rotary vane vacuum pump

BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to a rotary vane type vacuum pump, particularly in an industry that is required to comply with specific hygiene regulations when the pump is in operation or during the cleaning process.

Rotary vane vacuum pumps have been around for a long time. This type of pump has a rotor with a plurality of blades (referred to as "blades" that slide in the radial direction and ensure that the pumped air is delivered.

An example of such a pump is described in the published European Patent Application No. EP 0 166 807. In particular, as can be seen in Figure 1 of this document, a "conventional" vane pump is provided with blades at some locations on the exterior that can form a retention zone of liquid or solid or prevent natural flow. This makes this type of pump not very suitable or even completely unsuitable for a particular application.

In fact, liquids or solids can deposit and stagnant in the retentate area on the surface of the pump, resulting in the production of pathogenic microorganisms (mold, bacteria, etc.), posing a risk of contamination.

The main object of the invention is therefore to propose a rotary vane vacuum pump which does not have the disadvantages mentioned above and which is particularly useful in environments subject to strict hygiene standards.

This object is achieved by a rotary vane vacuum pump with special features which is such that all visible surfaces of the pump are set in such a way that they avoid elements which tend to retain liquid or solid retention. In particular, on at least a portion of such a pump, such a pump can be provided with a means of protection against surfaces or voids that tend to retain liquid or solids.

This pump has the advantage of being easy to clean. It is therefore suitable for all applications in industries that need to comply with specific hygiene regulations.

1‧‧‧Drive motor

2‧‧‧ pumping room

3‧‧‧Export

5‧‧‧Cooling blades

6‧‧‧Protection means (semi-cylindrical)

7‧‧‧Electrical sheath

8, 9, 10, 11, 12‧‧‧ upper surface

13, 14 ‧ ‧ support

15‧‧‧ upper surface

16‧‧‧Cooling blades

17‧‧‧Drive motor

18‧‧‧Cylinder

19, 20‧‧ ‧ orifice

21, 22, 23‧‧‧ upper surface

24‧‧‧ Oil mist separator

25‧‧‧Support block

V1‧‧‧ heat exchanger

V2‧‧‧ intermediate cylinder

Other features and advantages of the present invention will now be described in detail below, which are schematically illustrated with reference to the accompanying drawings: Figure 1: a rotary vane vacuum pump according to the prior art of the present invention; Fig. 2: a pump according to Fig. 1, It is shown in accordance with a first embodiment of the present invention; FIGS. 3, 4, and 5 are a front perspective view, a rear perspective view, and a front perspective view of the pump in accordance with a second embodiment of the present invention; 6. Figures 7 and 8: views of a pump according to a second embodiment corresponding to Figures 3, 4 and 5, respectively, which is equipped with an oil mist separator.

As already mentioned, the rotary vane vacuum pump according to the invention is characterized in that all visible surfaces above it are set in such a way that they avoid elements which tend to retain liquid or solids. Such surfaces must be external, they can be formed by cooling blades, and they are located in the upper half of the vacuum pump, assuming that the surface located in the lower half of the vacuum pump is unable to retain liquid or solid due to gravity. Here, it seems important to indicate that the adjectives "top half" and "lower half" used herein (and those in the specification and claims) refer to the operation of the pump or when it is ready for operation. Normal position.

In order to achieve the lack of an upper half surface of an element that tends to retain liquid or solids, it is especially possible to design the surface of the upper half in a smooth manner. This can be achieved during the production of the components of the pump, for example during the turning of the outer wall of the pumping chamber.

Alternatively, the pump may also be provided with protection means for the upper half surface on at least a portion. These means of protection must also have pockets, such as grooves, in which the pockets are located in the upper half of the rotary vane vacuum pump to allow liquid or solid to remain therein.

<First Embodiment>

To assist in understanding the first embodiment of the present invention, reference may be made first to Figure 1, which presents a prior art rotary vane vacuum pump.

The pump particularly includes a drive motor, such as an air-cooled asynchronous motor. It is well understood that depending on the construction design, it is also possible to use another type of motor, including a water-cooled motor. The motor is coupled to the pumping chamber 2. Its purpose is to rotationally drive the latter rotor so that the pump can meet its pumping function. The intermediate cylinder V2 drives the drive motor to the pumping chamber 2 in succession, and the intermediate cylinder normally contains the connecting elements between the drive motor and the pumping chamber 2.

Such a pumping chamber 2 is known per se; it typically comprises a rotor that is received in a cylindrical bore with blades.

The pumping chamber 2 can be supplied with oil, ie an oil circulation system for lubrication in this example to ensure sealing and allow heat exchange.

The oil is separated from the gas pumped into the oil mist separator (not shown) in such a manner that the air that exits through the outlet 3 and is recirculated to the atmosphere is purged of the oil it contains.

The pumping chamber 2 is similarly connected to a heat exchanger V1 with an integrated ventilator (not shown) for cooling the heat generated by the pumping chamber 2 during operation.

The drive motor 1 and the pumping chamber 2 are preferably detachably connected, which allows either of them to be replaced in the event of a malfunction.

As best seen in Figure 1, the pumping chamber 2 and the drive motor 1 contain cooling blades 5 therearound. Such a blade in principle results in the pump according to the prior art being unsuitable for use in areas where it is desirable to meet certain hygienic conditions and to be easily cleaned in the field, as as already explained above, the blade may retain a liquid or solid.

Thus, it can be seen from the first embodiment of the invention with reference to Figure 2 that all of the upper surfaces of the pump (and thus all surfaces visible from above) are set in such a way that they avoid the tendency to retain liquid or solid. It can be seen from the analysis of Fig. 2 that such smooth surfaces can be obtained by: they are formed in such a way that they do not include elements which tend to retain liquid or solids; or provide protection means which themselves avoid easy retention of liquids Or a solid surface or pocket.

Figure 2 shows that the upper surface of a portion of the pump (particularly the portion of the pumping chamber 2) contains only a smooth surface. These surfaces therefore do not contain any elements that tend to retain liquid or solids, thus allowing any liquid that may land on the pump to have a natural flow or any solids that naturally slide. Furthermore, FIG. 2 also shows other possibilities for achieving the extraordinary features of the invention, namely the protective means 6 like caps, ie they have a substantially semi-cylindrical shape, in this case covering the drive motor 1 The upper part. Of course, it is well understood that a similar pump can be implemented in accordance with the spirit of the present invention, wherein the protective means 6 can be located elsewhere in the pump, such as on the pumping chamber 2.

As described above, the "upper portion" refers to a case where the pump according to the present invention is horizontally disposed, that is, when the rotating shaft of the driving motor 1 is substantially the same as the rotating shaft of the rotor of the pumping chamber 2 and is parallel to the ground, the pump The supports 13, 14 are normally lying flat on the ground (or the support is parallel to the ground).

The adverb "substantially" as used above means that the shape of the semi-cylindrical body 6 is of course conformed to the shape of the drive motor 1, for example having a slit to allow the protrusion of the electrical sheath 7.

According to FIG. 2, the semi-cylindrical body 6 covers only the upper blade 5 of the drive motor, and the lower blade 16 is exposed at the lower portion of the drive motor 1.

Preferably, the semi-cylindrical body 6 is detachable, This has the advantage that it can be easily accessed by the drive motor 1 with inspection and thorough cleaning.

It is also preferred to provide at least a certain and ideally all of the upper surfaces of the drive motor 1 and/or the pumping chamber 2 (i.e. those surfaces which are visible from above) to be inclined downwards so that they are allowed to be removed during cleaning. The liquid or solid on these surfaces now flows away or slips away to remove these liquids or solids.

Examples of the upper surface may be reference numerals 8, 9, 10 and 11 for the pumping chamber 2 in Fig. 2 and reference numerals 12 and 15 for driving the motor 1.

When the supports 13 and 14 lie flat on the ground, the angle of inclination of the surface is preferably at least 5 degrees with respect to the ground.

Preferably, it is similarly provided that the oil mist separator comprises a support block that is common to the filter and the heat exchanger for the oil to make it compact, easy to access and easy to clean.

<Second embodiment>

A second embodiment of the present invention is shown in Figs. 3 to 7.

As seen in these figures, the rotary vane vacuum pump comprises a pumping chamber 2, which can be as shown in Figures 1 and 2 and which is connected to a drive motor 17. This specifically includes a double-layered cover having an exterior formed by the cylinder 18, as shown in Figure 3, with all or nearly all of its outer surface being smooth. The interior of the double-layer cover is in fact a casing of the motor not visible in Figure 3, which in a known manner comprises the normal components of a rotary vane vacuum pump motor, The motor can be an asynchronous drive motor.

Preferably, the outer surface of the cylinder 18 is smooth, and its outer surface (compared to Figure 2) is generally provided with cooling fins 16 as compared to the first embodiment.

The cylinders 18 are spaced from the containment casing (whether smooth or not) in a spaced manner such that a space is formed to allow refrigerant (e.g., liquid, particularly water) to circulate through the orifices 19 and 20.

The advantage of cooling with water is that the heat generated by the drive motor 17 can be removed without having to involve the blades 16 (Fig. 2) whose surface allows heat exchange with the air.

Preferably, the cylinder 18 is occluded, i.e., its free end is closed to facilitate cleaning of the pump.

Generally, in the present embodiment, the cylinder 18 is not detachable because it is fixed to the outer casing of the drive motor 17. However, it is also contemplated that the cylinder 18 can also be removed in a particular embodiment.

As with the first embodiment according to the invention, it is advantageous to provide a certain (preferably all) upper surface (e.g., the surfaces of 8, 9, 10, 11, 15, 21, 22 and 23) having an inclination.

Additionally, when using a lubricated vane pumping chamber 2, an oil mist separator as seen in Figures 6, 7 and 8 will typically be provided. Preferably, the oil mist separator includes a support block that is common to the filter and the heat exchanger 25 for the oil, which makes the overall structure compact, easy to access, and easy to clean.

What has just been described is the multiple realities of the device according to the invention. The invention is not limited to the scope of the invention as defined by the scope of the patent application.

Those skilled in the art will appreciate the possibilities of development, modification, and application of pumps in accordance with the present invention, particularly in other areas where increasing hygiene levels are important.

1‧‧‧Drive motor

2‧‧‧ pumping room

6‧‧‧Protection means (semi-cylindrical)

7‧‧‧Electrical sheath

8, 9, 10, 11, 12‧‧‧ upper surface

13, 14 ‧ ‧ support

15‧‧‧ upper surface

16‧‧‧Cooling blades

Claims (13)

A rotary vane type vacuum pump comprising a drive motor (1, 17) cooperating with a vacuum vane pumping chamber (2), wherein the pump is configured such that all visible surfaces from above are such that they avoid easy retention of liquid or Solid component. A rotary vane type vacuum pump according to the first aspect of the invention, wherein at least a part of the pump is provided with a protection means (6) which avoids surfaces or cavities which are liable to retain liquid or solid. A rotary vane type vacuum pump according to claim 2, wherein the protection means has substantially the shape of a semi-cylindrical body (6) covering at least one upper portion of the pump. A rotary vane type vacuum pump according to claim 2 or 3, wherein the protection means (6) is removable. A rotary vane type vacuum pump according to any one of claims 2 to 4, wherein the protection means (6) is provided only at the level of the drive motor (1). A rotary vane type vacuum pump according to one of the above claims, wherein the drive motor (1) is an air-cooled asynchronous drive motor. A rotary vane type vacuum pump according to claim 1, wherein the drive motor (17) comprises a double-layered outer casing and the outer portion is formed by a cylinder (18). A rotary vane type vacuum pump according to item 7 of the patent application, wherein the cylinder (18) is a closed cylinder. Rotary vane vacuum according to item 7 or 8 of the patent application The pump, wherein the drive motor (17) is a water-cooled asynchronous drive motor, has a housing and forms a space with the cylinder (18) that can circulate refrigerant. A rotary vane type vacuum pump according to one of the above claims, wherein the drive motor (1) when the rotation shaft of the drive motor (1, 17) and the rotation shaft of the rotor of the pumping chamber (2) are parallel to the ground And 17) and/or at least the particular upper surfaces (8, 9, 10, 11, 15, 21, 22 and 23) of the pumping chamber (2) are downwardly inclined. A rotary vane type vacuum pump according to one of the above claims, wherein the vanes are lubricated by oil. A rotary vane type vacuum pump according to claim 11 wherein the pumping chamber (2) is connected to the oil mist separator (24). A rotary vane type vacuum pump according to claim 12, wherein the oil mist separator (24) comprises a support block (25) common to the filter and the heat exchanger for oil.