Scroll pump seal, scroll pump and method

Abstract

A scroll pump seal for inhibiting fluid flow into and out of a pumping chamber defined between a first scroll and a second scroll of a scroll pump is disclosed. The first scroll member and the second scroll member are configured for relative orbital motion. The scroll pump seal includes: an annular body adapted to be mounted about a shaft of a scroll pump and fixed relative to one of a first scroll and a second scroll; and a first sealing element including an inner annular protrusion and an outer annular protrusion extending from an axial end surface of the annular body, the inner annular protrusion and the outer annular protrusion being configured to contact the other of the first scroll and the second scroll where the annular body is not relatively fixed. In this way, the scroll pump seal may provide improved sealing to inhibit fluid flow into and out of the pumping chamber. Accordingly, leakage may be reduced and pumping performance of the scroll pump may be improved.

Description

Technical Field

[0001] The field of the present invention relates to a scroll pump, and more particularly to a scroll pump seal for inhibiting fluid flow into and out of a pumping chamber defined between a first scroll member and a second scroll member of the scroll pump. Background Art

[0002] A vortex pump comprising a first scroll and a second scroll configured for relative orbital motion is known. A pumping chamber is defined between the first scroll and the second scroll. A seal may be positioned between the first scroll and the second scroll to inhibit leakage of fluid from outside the scroll mechanism into the pumping chamber. Although such vortex pumps exist, they also have disadvantages. Therefore, it is desirable to provide an improved vortex pump and vortex pump seal. Summary of the invention

[0003] One aspect provides a vortex pump seal for inhibiting fluid from flowing into and out of a pumping chamber defined between a first vortex member and a second vortex member of the vortex pump, the first vortex member and the second vortex member being configured for relative orbital motion, the vortex pump seal comprising: an annular body adapted to be mounted around an axis of the vortex pump and fixed relative to one of the first vortex member and the second vortex member; and a first sealing element comprising an inner annular protrusion and an outer annular protrusion extending from an axial end surface of the annular body, the inner annular protrusion and the outer annular protrusion being configured to contact the other of the first vortex member and the second vortex member where the annular body is not relatively fixed.

[0004] Some vortex pump seals prevent leakage into the pumping chamber (or flow path) of a vortex pump (or vortex mechanism) by providing a protrusion (or lip). For example, GB2503723B discloses a vortex pump having an axial lip seal between an orbiting scroll and a fixed scroll to resist leakage of fluid from outside the vortex mechanism into the flow path. The axial lip seal is fixed relative to the orbiting scroll or the fixed scroll, and seals against the other of the orbiting scroll or the fixed scroll so that the orbital motion relative to the other scroll is imparted to the seal. The axial lip seal includes a lip angled toward the axis of the vortex pump, and the axial lip seal is mounted around the axis.

[0005] This aspect recognizes that such vortex pump seals have shortcomings in their ability to inhibit fluid leakage. In particular, these vortex pump seals cannot effectively prevent pumping medium from leaking out of the pumping chamber. In addition, the seal strength to prevent unwanted fluid from leaking into the pumping chamber may be limited. Pumping material leaking out of the pumping chamber may cause the pumping performance of the vortex pump to deteriorate. Surrounding fluid leaking into the pumping chamber may also reduce pumping performance and potentially damage the vortex pump. Fluid leaking into the pumping chamber may draw unwanted lubricants, oils and particles into the pumping chamber, which may be harmful or damaging to the vortex pump.

[0006] Therefore, this aspect provides a vortex pump seal. The vortex pump seal can inhibit fluid from flowing into and out of a pumping chamber defined between a first vortex and a second vortex of the vortex pump. The first vortex and the second vortex are configured to perform relative orbital motion. The vortex pump can be a vortex vacuum pump. The vortex pump seal includes an annular body (or annular portion). The annular body can be adapted to be mounted around the shaft of the vortex pump. The annular body can be fixed relative to one of the first vortex and the second vortex. The vortex pump seal can include a first sealing element. The first sealing element can be used for sealing between the first vortex and the second vortex of the vortex pump. The first sealing element may include an inner annular protrusion (or inner lip). The first sealing element may include an outer annular protrusion (or outer lip). The inner and outer annular protrusions may extend from the axial end surface (or end portion) of the annular body. The inner annular protrusion and the outer annular protrusion may be configured to contact (or seal against) the other of the first vortex and the second vortex in which the annular body is not relatively fixed.

[0007] In this way, a vortex pump seal having two sealing protrusions is provided. The two protrusions can increase the sealing strength to prevent the fluid from moving in one or two directions. Therefore, leakage into and out of the pumping chamber can be reduced. This aspect also provides advantages over existing shaft seals. In particular, the high rotation speed of the pump shaft causes wear and therefore the shaft seal needs to be replaced regularly. The speed of the relative orbital motion between the first scroll and the second scroll is less than the rotation speed of the shaft. Therefore, providing a first sealing element between the scrolls means that the vortex pump seal of one aspect can last longer than similar shaft seals.

[0008] In some embodiments, the inner annular protrusion and the outer annular protrusion extend at an angle such that the inner annular protrusion is angled toward the shaft and the outer annular protrusion is angled toward the pumping chamber. In other words, the inner annular protrusion and the outer annular protrusion do not extend perpendicular to the axial end surface of the annular body. In this way, the inner annular protrusion is good at inhibiting leakage of surrounding fluids, lubricants, and particles into the pumping chamber, and the outer annular protrusion is particularly effective in inhibiting leakage of the pumping medium out of the pumping chamber. In addition, the use of angled protrusions can improve the strength of the seal because the seal can be strengthened as the pressure difference on both sides of the angled protrusion increases.

[0009] In some embodiments, the inner and outer annular protrusions together define a V-shape. In this way, leakage into and out of the pumping chamber can be mitigated, as this shape forms a particularly effective seal for fluid being drawn into and out of the pumping chamber. In some embodiments, the inner and outer annular protrusions include curved portions so that they are not completely linear. This can help to strengthen the seal as the pressure differential across the seal increases.

[0010] In some embodiments, the inner annular protrusion and the outer annular protrusion extend the same length. In this way, the seal into the pumping chamber and the seal out of the pumping chamber can have similar strengths.

[0011] In some embodiments, the outer annular protrusion extends beyond the radially outer surface of the annular body. Longer protrusions can form a stronger seal because they are pressed more into one of the first or second scroll members. However, when selecting the length of the protrusion, there is a trade-off between saving space and sealing strength.

[0012] In some embodiments, the vortex pump seal includes a second sealing element for inhibiting fluid flow between the annular body and the shaft of the vortex pump, the second sealing element including an additional annular protrusion (or lip) extending from the radial inner surface of the annular body. In this way, an additional seal is provided to block the flow path into and out of the pumping chamber to further inhibit leakage into and out of the pumping chamber. Therefore, the strength of the seal can be improved, and thus the pumping performance can be improved.

[0013] In some embodiments, the additional annular protrusion is angled toward the axial end surface comprising the first sealing element. In this way, depending on which of the first and second scroll members the scroll pump seal is fixed relative to, the additional annular protrusion can be particularly good at preventing leakage into or out of the pumping chamber.

[0014] In some embodiments, the second sealing element comprises a second further annular protrusion. In this way, the seal produced by the second sealing element can be strengthened. Therefore, leakage into and out of the pumping chamber can be further reduced.

[0015] In some embodiments, the further annular protrusion and the second further annular protrusion together define a V-shape. In this way, one of the first further annular protrusion and the second further annular protrusion is particularly good at preventing leakage out of the pumping chamber, and the other is particularly good at preventing leakage into the pumping chamber. This can reduce overall leakage.

[0016] In some embodiments, the scroll pump seal includes a biasing member configured to bias the first sealing element toward the other of the orbiting scroll and the fixed scroll to which the annular body is not relatively fixed. In this way, the sealing contact can be strengthened, thereby reducing leakage.

[0017] In some embodiments, the biasing member comprises a spring.

[0018] In some embodiments, the biasing member is integral with the annular body. In this way, the biasing member can be manufactured or formed together with the vortex pump seal. In some embodiments, the biasing member is made of the same material as the annular body.

[0019] In some embodiments, the first sealing element includes an intermediate annular protrusion (or lip) extending from the axial end surface of the annular body between the inner annular protrusion and the outer annular protrusion. In this way, additional sealing can be provided to improve the seal formed by the vortex pump seal. This embodiment is particularly effective in combination with a biasing member to help all three protrusions (or sealing members or lips) fully contact the other of the first scroll and the second scroll that is not relatively fixed to the annular body.

[0020] In some embodiments, the annular body and the first sealing element are integral with each other. In some embodiments, the annular body and the first sealing element are made of the same material. In some embodiments, the body and the second sealing element are integral with each other. In some embodiments, the annular body and the second sealing element are made of the same material.

[0021] In some embodiments, the annular body is secured to one of the first scroll and the second scroll via a friction fit.

[0022] In some embodiments, the annular body includes an annular groove containing an O-ring for securing the annular body to one of the first scroll and the second scroll and for inhibiting fluid flow between the annular body and one of the first scroll and the second scroll. In this way, the scroll pump seal can be secured to the appropriate scroll and fluid flow between the scroll pump seal and the scroll is inhibited or prevented.

[0023] In some embodiments, the scroll pump seal is made of at least one polymer, optionally wherein the at least one polymer is a polytetrafluoroethylene filled polyamide.

[0024] In some embodiments, the vortex pump seal includes grease positioned between the inner annular protrusion and the outer annular protrusion. In this way, the first sealing element can be supported and the seal can be strengthened. Therefore, leakage can be reduced and the performance of the pump can be improved. Similarly, when the vortex pump seal includes a second sealing element, the second sealing element includes an additional annular protrusion and a second additional annular protrusion, grease can be provided between these protrusions to increase the sealing strength.

[0025] On the other hand, a vortex pump is provided, comprising: a first vortex member and a second vortex member, which are configured for relative orbital motion; a shaft, which is configured to impart relative orbital motion to the first vortex member and the second vortex member when driven; and a vortex pump seal according to one aspect, which is mounted around the shaft and fixed relative to one of the first vortex member and the second vortex member.

[0026] In some embodiments, the scroll pump seal is made of the same material as the tipseals of the first and second scrolls.

[0027] On the other hand, a method for positioning a vortex pump seal is provided, comprising: installing a vortex pump seal according to one aspect around an axis; and fixing the vortex pump seal relative to one of a first scroll member and a second scroll member so that the first sealing element contacts the other of the first scroll member and the second scroll member where the annular seal is not relatively fixed, and the first scroll member and the second scroll member are configured for relative orbital motion.

[0028] In some embodiments, the method includes positioning an O-ring in an annular groove defined in an annular body of a vortex pump seal. This can be performed before the vortex pump seal is fixed relative to one of the first and second vortex members. However, the steps of another aspect can be performed in any order.

[0029] Further particular and preferred aspects are set out in the accompanying independent and dependent claims. Features of the dependent claims may be combined with features of the independent claims as appropriate or in a manner other than that explicitly set out in the claims.

[0030] Where an apparatus feature is described as being operable to provide a function, it will be appreciated that this includes apparatus features that provide that function or that are adapted or configured to provide that function. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Embodiments of the present invention will now be further described with reference to the accompanying drawings, in which:

[0032] Figure 1 shows a portion of a front cross-sectional view of a scroll pump according to one embodiment;

[0033] Figure 2 shows a portion of a front cross-sectional view of a scroll pump according to one embodiment;

[0034] Figure 3 shows a portion of a front cross-sectional view of a scroll pump according to one embodiment; and

[0035] Figure 4 A flow chart is shown illustrating steps in a method of positioning a scroll pump seal according to an embodiment. DETAILED DESCRIPTION

[0036] Before discussing the embodiments in more detail, an overview will first be provided.

[0037] Some embodiments provide a vortex pump seal for inhibiting fluid from flowing into and out of a pumping chamber (leakage). The pumping chamber is defined between a first scroll member and a second scroll member of the vortex pump. The first scroll member and the second scroll member are configured to perform relative orbital motion. The vortex pump seal includes: an annular body, which is suitable for being mounted around the axis of the vortex pump and fixed relative to one of the first scroll member and the second scroll member; and a first sealing element, the first sealing element including an inner annular protrusion and an outer annular protrusion extending from an axial end surface of the annular body, the inner annular protrusion and the outer annular protrusion being configured to contact the other of the first scroll member and the second scroll member where the annular body is not relatively fixed.

[0038] There are small flow paths between the components of a vortex pump. A seal can be radially positioned within the innermost scroll of a pumping chamber or vortex mechanism to help prevent leakage into and out of the innermost scroll. Existing seals are fixed relative to one of an orbiting scroll and a fixed stator scroll and have a single lip that forms a seal against the scroll that is not fixed relative to the scroll. The single lip is angled toward the shaft to help inhibit leakage into the pumping chamber. However, existing seals do not seal against leakage of pumped medium from inside the pumping chamber to outside the pumping chamber. In addition, having only a single sealing lip means that known seals have limited strength.

[0039] By providing two sealing protrusions, the effective sealing strength may be increased.Thus, leakage into and out of the pumping chamber in one or both directions may be reduced.

[0040] The inner annular protrusion may be angled toward the shaft and the outer annular protrusion may be angled toward the pumping chamber. The protrusions may form a V-shape. By angling the sealing protrusions in opposite directions, an effective seal may be created, inhibiting fluid flow into and out of the pumping chamber.

[0041] The use of an additional sealing element to seal between the seal body and the shaft of the vortex pump can be used to further limit fluid flow and leakage. The second sealing element can have one or two protrusions. If two, they can be angled so that they form a V shape.

[0042] A third protrusion may be added to either the first sealing element or the second sealing element to further enhance the seal. The third protrusion may be added between already angled or V-shaped protrusions.

[0043] A biasing member may be provided to urge the sealing protrusion of the first sealing element to produce an effective seal. The biasing member may be a distinct feature, or it may be integral with the body of the seal. If integral, the force of the biasing member may be generated by the shape and / or structure of the seal.

[0044] Another way to increase seal strength is by including grease between the protrusions to resist collapse.

[0045] Vortex Pumps

[0046] As in known vortex pumps, a motor drives a shaft. The shaft affects the relative orbital motion of a set of scroll members. The relative orbital motion pumps the fluid along a flow path from an inlet to an outlet via a pumping chamber consisting of a plurality of concave cavities. The flow path extends between the scroll members in a generally involute path. More specifically, the walls of the scroll members define a scroll portion through which the fluid moves and is compressed toward the center of the scroll member. Therefore, there is a pressure difference between adjacent scroll portions. These scroll portions are sealed using top seals known in the prior art. However, further sealing may be required to prevent leakage into or out of the innermost scroll portion.

[0047] During pump operation, the relatively high pressure in the inner scroll means that the compressed gas wants to escape. The path of least resistance is out of the pump outlet; however, the fluid will escape from the scroll mechanism around the shaft and the front shaft bearing. Therefore, leakage of fluid out of the pumping chamber will occur.

[0048] The opposite problem occurs when the pump stops and there is an immediate drop in pressure inside the scroll mechanism. When the pumping chamber is balanced, fluid from outside the pumping chamber at a higher ambient pressure can be drawn into the scroll mechanism and can drag other contaminants, such as oil, from the pump bearings. As a result, fluid leakage into the pumping chamber can occur.

[0049] Vortex Pump Seals

[0050] Figure 1An embodiment of a vortex pump seal 10 is shown, which is used in a vortex pump to inhibit fluid from flowing into and out of a pumping chamber 30 defined between a first vortex 12 and a second vortex 14 of the vortex pump. The first vortex 12 and the second vortex 14 are configured to perform relative orbital motion. One of the first vortex 12 and the second vortex 14 can be a fixed or stator vortex, and the other can be an orbital vortex. Alternatively, they can both be orbital vortexes. The relative orbital motion is imparted to the vortex by a motor drive shaft 16.

[0051] The scroll pump seal 10 includes an annular body 18 defining an annular groove 28 for receiving an O-ring 26 , and a first sealing element 20 having an inner annular protrusion 22 and an outer annular protrusion 24 .

[0052] The seal 10 is positioned in the opening defined between the first scroll member 12, the second scroll member 14 and the shaft 16, at a position radially inward of the pumping chamber 30 (eg, Figure 2 The annular body 18 is mounted around the shaft 16 and is fixed relative to the first scroll member 12.

[0053] The body 18 is secured using a friction fit. More specifically, the seal 10 includes an O-ring 26 positioned within an annular groove 28 defined by the body 18. The O-ring 26 is configured to secure the seal 10 relative to the first scroll 12 and inhibit fluid flow between the seal 10 and the first scroll 12.

[0054] The first sealing element 20 is integral with the annular body 18 and is made of the same material as the body 18. The first sealing element 20 includes an inner annular protrusion 22 and an outer annular protrusion 24. The protrusions 22, 24 extend away from the annular body 18 at opposite angles so that they form a V-shape, wherein the inner annular protrusion 22 is located radially inside the outer annular protrusion 24. One end of the protrusions 22, 24 contacts the second scroll member 14 so that a seal is formed between the first scroll member 12 and the second scroll member 14. A seal is formed relative to both when the scroll members 12, 14 are stationary and moving (relative orbital motion).

[0055] In use, the seal 10 is used to inhibit the flow of fluid between the first scroll 12 and the second scroll 14, thereby inhibiting the flow of fluid into and out of the pumping chamber 30 or leakage into or out of the pumping chamber 30. The first sealing element 20 is configured to contact the second scroll 14 before, during and after the operation of the scroll pump, so that leakage is inhibited during different operating conditions of the scroll pump. The inner annular protrusion 22 is particularly good at inhibiting leakage into the pumping chamber 30 because it is angled away from the pumping chamber 30. This is particularly useful immediately after the pump stops running, because as discussed above, leakage into the pumping chamber 30 is prevalent at this time. The outer annular protrusion 24 is particularly good at inhibiting leakage out of the pumping chamber 30 because it is angled toward the pumping chamber 30. This is particularly useful when the pump is working, because as discussed above, leakage out of the pumping chamber 30 is prevalent at this time.

[0056] Modifications to the described embodiments will be apparent to those skilled in the art. For example, the annular body 18 may be fixed relative to the second scroll 14 rather than the first scroll 12. In this case, the first sealing element 20 contacts the scroll that is not relatively fixed to the annular body 18. In addition, although the seal 10 is fixed relative to the first scroll by a friction fit, any suitable attachment mechanism may be used, such as by an adhesive. The protrusions 22, 24 of the first sealing element 20 may not be angled-that is, they may extend perpendicular to the axial end surface of the annular body 18. The protrusions 22, 24 may form a combination of straight and angled. The protrusions may extend at similar angles, or at different angles so that they are asymmetric. These arrangements may provide improved sealing to reduce leakage into or out of the pumping chamber 30.

[0057] Figure 2 A second embodiment of a vortex pump seal is shown. The vortex pump seal 100 is similar to the seal 10, but with the addition of a second sealing element 36. The second sealing element 36 includes at least one protrusion extending from the radial inner surface of the annular body 18. The second sealing element 36 is integral with the annular body 18 and is made of the same material as the body 18. The protrusion is angled toward the axial end surface of the body 18, making it particularly effective at inhibiting fluid from flowing out of the pumping chamber 30, through the shaft bearing and into the surrounding environment.

[0058] In use, scroll pump seal 100 is similar to seal 10 except that second sealing element 36 provides a seal between annular body 18 and shaft 16 to inhibit leakage between these components before, during and after operation of the scroll pump, i.e. when shaft 16 is rotated by the motor to achieve relative orbital motion between scroll members 12, 14.

[0059] Modifications to the described embodiments will be apparent to those skilled in the art. For example, the at least one protrusion of the second sealing element 36 may be angled toward or away from the pumping chamber 30 to inhibit leakage out of or into the pumping chamber 30. The at least one protrusion of the second sealing element 36 may include two protrusions. The at least one protrusion of the second sealing element 36 may not be angled, i.e., it may be perpendicular to the radial inner surface of the body 18. If there are two, the protrusions may form a V-shape. Alternatively, they may be at different angles. The protrusions of the first sealing element 20 and the second sealing element 36 may be different. The second sealing element 36 may include an intermediate protrusion similar to that discussed below. These arrangements may provide improved sealing to reduce leakage into and out of the pumping chamber 30.

[0060] Figure 3 A third embodiment of a scroll pump seal is shown. Scroll pump seal 1000 is similar to seal 10 but with the addition of a biasing mechanism 40 and a first sealing element 20 including an intermediate protrusion 38 .

[0061] The intermediate protrusion 38 extends perpendicularly to the axial end surface of the annular body 18 between the inner annular protrusion 22 and the outer annular protrusion 24. Similar to the inner and outer annular protrusions 22 and the outer annular protrusion 24, the intermediate protrusion 38 is integral with the annular body 18 and is made of the same material as the annular body 18. The intermediate protrusion 38 provides an additional seal to further inhibit fluid flow between the first scroll member 12 and the second scroll member 14, thereby reducing leakage.

[0062] The biasing mechanism 40 includes a spring located on an axial end of the annular body 18, which is opposite to the end where the first sealing element 20 is located. In this way, the biasing mechanism 40 is configured to push against the first scroll member 12 so that the inner and outer annular protrusions 22, 24 and the intermediate protrusions 36 are urged toward the second scroll member 14 to enhance the sealing strength.

[0063] In use, scroll pump seal 1000 is similar to seal 10 except that biasing member 40 urges inner and outer annular projections 22 , 24 and intermediate projection 38 toward second scroll 14 to help maintain the seal, particularly during relative orbital motion between first scroll 12 and second scroll 14 .

[0064] Modifications to the described embodiments will be apparent to those skilled in the art. For example, the intermediate protrusion 38 may be angled. In addition, the biasing member 40 may be any suitable mechanism, not necessarily a spring. The biasing mechanism 40 may be integral with the annular body so that the structure of the annular body 18 naturally provides a biasing force. These arrangements may provide an improved seal to reduce leakage into and out of the pumping chamber 30.

[0065] Figure 4 A flow chart of a method of positioning a vortex pump seal (e.g., one of vortex pump seals 10, 100, 1000) is shown. At step 1010, the vortex pump seal is mounted around an axis (e.g., axis 16) of a vortex pump. At step 1020, the vortex pump seal is fixed relative to one of a first scroll and a second scroll (e.g., scroll 12 and scroll 14) of the vortex pump so that a first sealing element of the vortex pump seal contacts the other of the first scroll and the second scroll to which the annular seal is not relatively fixed. The first scroll and the second scroll are configured for relative orbital motion.

[0066] In other words, embodiments provide seals for sealing orbital or rotary motion (vortex pump seals). In some embodiments, a seal has 4 lips (2 pairs) that prevent internal and external leakage. One pair contacts the orbiting scroll and the second pair contacts the shaft. It is installed into a bore (opening) of the fixed scroll and is sealed by an O-ring in a groove through a piston O-ring. It can seal to surfaces perpendicular to the shaft and can also seal on the shaft. Effective sealing is provided even at slight pressure differences of 1 bar. The use of reverse lips allows for faster running-in and better sealing function.

[0067] This sealing solution improves GB2503723B and adds a seal that prevents unwanted loss of pumped medium from the pump. It can be extended and even provide additional sealing on the shaft.

[0068] The seal is made of the same material as the top seal, which can be EKL HS11041 (PA, PTFE filled) or any polymer material with good sealing properties and sufficient wear resistance. The idea is that there is always a slight overpressure (1.2 bar (a)) in the center of the fixed scroll and the gas wants to escape through the lowest resistance, which is mainly through the exhaust. However, the gas escapes from the mechanism around the front shaft bearing to enter the motor stator. The opposite problem occurs when the pump stops and the pressure inside the mechanism is lower than the surrounding atmospheric pressure. An embodiment attempts to prevent ambient air from rushing quickly to the pumping mechanism. The solution to these two problems can be found in the form of multiple reverse lips (protrusions) on the face of the seal facing perpendicular to the shaft and another set of reverse lips (protrusions) adjacent to the shaft. For seal life, the quality of the sealing surface is important for sealing and roughness. To improve the sealing effect, grease can be applied between the lip pairs in some embodiments. Compared with conventional seals, this provides additional gas retention and provides the opportunity to seal on the shaft surface where a higher surface quality can be achieved. In practice, any lip will provide some resistance to the gas, so a construction with multiple lips can improve the seal.

[0069] An embodiment provides a sealing solution utilizing a crown-shaped sealing element actuated by a spring and additionally sealed around an O-ring. Tightness values ​​of at least 10E-3 mbar*l / s can be achieved. By carefully designing the required stiffness and flexibility, the spring can be integrated into the seal.

[0070] Although illustrative embodiments of the present invention have been disclosed in detail herein with reference to the accompanying drawings, it is to be understood that the invention is not limited to the precise embodiments and that various changes and modifications may be made thereto by those skilled in the art without departing from the scope of the invention as defined by the appended claims and their equivalents.

[0071] Reference numerals

[0072] 10,100,1000 seals

[0073] 12,14 scroll parts

[0074] 16 axes

[0075] 18 Main Body

[0076] 20 first sealing element

[0077] 22,24 protrusions

[0078] 26O-ring

[0079] 28 slots

[0080] 30 Pumping chamber

[0081] 32 Tip Seals

[0082] 34 scroll part

[0083] 36 Second sealing element

[0084] 38 Middle protrusion

[0085] 40 biasing member

Claims

1. A scroll pump seal for inhibiting fluid from flowing into and out of a pumping chamber defined between a first scroll member and a second scroll member of a scroll pump, the first scroll member and the second scroll member being configured for relative orbital motion, the scroll pump seal comprising: an annular body adapted to be mounted around the axis of the scroll pump and fixed relative to one of the first scroll member and the second scroll member; and A first sealing element includes an inner annular protrusion and an outer annular protrusion extending from an axial end surface of the annular body, the inner annular protrusion and the outer annular protrusion being configured to contact the other of the first scroll member and the second scroll member to which the annular body is not relatively fixed.

2. The vortex pump seal according to claim 1, wherein: The inner and outer annular projections extend at an angle such that the inner annular projection is angled toward the shaft and the outer annular projection is angled toward the pumping chamber.

3. A vortex pump seal according to any one of the preceding claims, wherein: The inner annular protrusion and the outer annular protrusion together define a V-shape.

4. A vortex pump seal according to any one of the preceding claims, wherein: The scroll pump seal includes a second sealing element for inhibiting fluid flow between the annular body and the shaft of the scroll pump, the second sealing element including a further annular protrusion extending from a radially inner surface of the annular body.

5. The vortex pump seal according to claim 4, wherein: The further annular projection is angled towards the axial end surface comprising the first sealing element.

6. The vortex pump seal according to claim 4 or 5, wherein: The second sealing element comprises a second further annular projection.

7. The vortex pump seal according to claim 6, wherein: The further annular protrusion and the second further annular protrusion together form a V-shape.

8. A vortex pump seal according to any one of the preceding claims, wherein: The scroll pump seal includes a biasing member configured to bias the first sealing element toward the other of the orbiting scroll and the fixed scroll.

9. The vortex pump seal according to claim 8, wherein: The biasing member includes a spring.

10. The vortex pump seal according to claim 8 or 9, wherein: The biasing member is integral with the annular body.

11. A vortex pump seal according to any one of the preceding claims, wherein: The first sealing element includes an intermediate annular protrusion extending from the axial end surface of the annular body between the inner annular protrusion and the outer annular protrusion.

12. A vortex pump seal according to any one of the preceding claims, wherein: The annular body includes an annular groove containing an O-ring for fixing the annular body to the one of the first scroll member and the second scroll member and for inhibiting fluid flow between the annular body and the one of the first scroll member and the second scroll member.

13. A vortex pump seal according to any one of the preceding claims, wherein: The scroll pump seal is made from at least one polymer, optionally wherein the at least one polymer is a polytetrafluoroethylene filled polyamide.

14. A vortex pump comprising: a first scroll and a second scroll configured for relative orbital motion; a shaft configured to impart relative orbital motion to the first scroll member and the second scroll member when driven; A scroll pump seal according to any preceding claim, mounted about the shaft and fixed relative to one of the first and second scroll members.

15. The scroll pump according to claim 14, wherein: The scroll pump seal is made of the same material as the tip seals of the first and second scrolls.

16. A method for positioning a vortex pump seal, comprising: Mounting a vortex pump seal according to any one of claims 1 to 13 around a shaft; and The scroll pump seal is fixed relative to one of a first scroll and a second scroll configured for relative orbital motion such that the first sealing element contacts the other of the first scroll and the second scroll to which the annular seal is not fixed.

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