Slide ring seal assembly

Abstract

The invention relates to a slide ring seal assembly, comprising a slide ring seal (2) having a rotating slide ring (3) with a first sliding surface, and a stationary slide ring (4) with a second sliding surface, which define a sealing gap (5) between the sliding surfaces, a wired unit (7), which is arranged on one of the slide rings, wherein the wired unit (7) has a cable (71) which is designed to supply electrical energy and / or to transmit information, and a protective pin (6), which is designed to provide protection for the cable (71), wherein the protective pin (6) has a recess (8) through which the cable (71) fed from the slide ring provided with the wired unit is passed.

Description

[0001] Mechanical seal arrangement

[0002] Description

[0003] The present invention relates to a mechanical seal arrangement with a cable-connected unit, for example a sensor, which is arranged in a sliding ring and is connected by means of a cable for power supply and / or for information exchange.

[0004] Mechanical seal assemblies are known in various designs from the prior art. Recently, there have been increasing attempts to obtain information about the condition of a mechanical seal, particularly from the sliding surfaces of the mechanical seal. For this purpose, wired units, such as sensors, are arranged on an outer circumference or in recesses in the seal ring. The cables connected to the wired units must be routed away from the seal ring and are often exposed to extreme external conditions with regard to temperature, pressure, or medium. Such cables must also be able to compensate for any settling movements of the seal rings, particularly in the axial direction. This frequently results in a cable break, meaning the connection to the wired unit is no longer maintained.

[0005] It is therefore an object of the present invention to provide a mechanical seal arrangement with a cable-connected unit which, with a simple structure and simple, cost-effective manufacture, enables secure cable contacting of a unit arranged in or on the mechanical seal.

[0006] This object is achieved by a mechanical seal arrangement having the features of claim 1. The subclaims show preferred developments of the invention.

[0007] The mechanical seal arrangement according to the invention with the features of claim 1 has the advantage that a wired unit, for example a sensor or the like, which is contacted via a cable, can be arranged in an optimal position on or in a slide ring. The cable can be safely guided to a stationary component, for example a housing component, without risk of damage during operation. This is achieved according to the invention in that the mechanical seal arrangement has a mechanical seal with a rotating and a stationary slide ring, which define a sealing gap between their sliding surfaces. The wired unit is arranged in or on one of the slide rings. The cable, which is connected to the wired unit, is designed to supply power and / or information to the wired unit. A protective pin ensures protection of the cable.The protective pin is arranged on the sliding ring comprising the cable-connected unit and is configured to provide protection for the cable. The protective pin has a recess through which the cable fed from the sliding ring is guided. Thus, the supplied cable can be safely guided away from the sliding ring without risk of damage to the cable during operation of the mechanical seal assembly. To prevent damage caused by kinking the cable, it is preferably guided away from the sliding ring in an arc.

[0008] Particularly preferably, the cable-connected unit is arranged on the stationary sliding ring. The protective pin is arranged between the stationary sliding ring and the stationary component, in particular a housing component or the like. The protective pin thus provides a connection between the stationary sliding ring and the stationary component and protects the cable from the stationary sliding ring to the stationary component.

[0009] The cable supplied by the stationary sliding ring is preferably inserted directly from the stationary sliding ring into the recess in the protective pin. Preferably, the cable is completely arranged and protected within the recess of the protective pin, from the stationary sliding ring to the stationary component.

[0010] Further preferably, the sliding ring comprising the cable-connected unit has a groove on its outer circumference. The protective pin is arranged in the groove. The groove preferably runs in the axial direction; more preferably, the groove runs completely in the axial direction through the sliding ring.

[0011] A particularly compact and robust design is ensured if the protective pin preferably has a slotted area and the recess in the slotted area includes a slot. The cable is guided from the sliding ring, preferably directly, into the slot and is thus protected by the walls surrounding the slot.

[0012] Particularly preferably, the slot is open on one side in the axial direction and is designed as a radial through-slot, so that the protective pin has a first and a second free arm, between which the slot is formed. This means that a uniform protective pin can be used with a variety of different types of mechanical seal. The protective pin preferably has a head region which adjoins the slot region. The recess comprises a through-opening in the head region, which is arranged in the head region in such a way that the slot of the slot region is arranged at one end of the through-opening in the head region. The slot thus merges directly into the through-opening. This means that the cable can be easily inserted from the slot into the through-opening without there being any risk of damage.

[0013] Further preferably, the sliding ring comprising the cable-connected unit is axially movable, in particular by providing a preloading element whose preloading force acts on the axially movable sliding ring. This also allows the axially movable sliding ring to be provided with a cable-connected unit and, in particular, enables monitoring of the axially movable sliding ring, for example, using cable-connected sensors. Despite the axial movements of the sliding ring, no damage to the cable occurs due to the provision of the protective pin. This allows the axially movable sliding ring comprising the cable-connected unit to be monitored, for example, using a sensor, even over its entire service life.

[0014] Further preferably, multiple cables are routed from the sliding ring to the stationary component through a common recess in the protective pin. Thus, despite the provision of multiple cable-connected units on a sliding ring, only a single, common protective pin needs to be provided to route all cables of the cable-connected units of the sliding ring to the housing.

[0015] A particularly effective protective effect of the protective pin is achieved when the cable supplied by the sliding ring is routed exclusively in the slot of the protective pin. This enables particularly good shielding of the protective pin, whereby it is also possible for the protective pin to be located in the medium to be sealed, which may, for example, have high temperatures and / or high pressure.

[0016] Particularly preferably, the cable-connected unit is arranged in a blind hole in the sliding ring, wherein the blind hole is arranged at an acute angle, in particular approximately 10° to 40°, more particularly approximately 20°, to the sealing gap. Thus, the cable of the cable-connected unit is led out of the sliding ring at a relatively steep angle and, without a protective pin, is at high risk of kinking or other damage. The protective pin also protects the cable, which is led out of the sliding ring at an acute angle.

[0017] More preferably, the protective pin is further configured to transmit torque from or to the sliding ring comprising the cable-connected unit and another component. Thus, in addition to protecting the cable, the protective pin can also perform a torque transmission function between the sliding ring and another component. Such a protective pin preferably has a cap on the slotted area of ​​the protective pin, through which the torque is introduced into the protective pin.

[0018] The cable of the wired unit is preferably a power cable and / or an information cable.

[0019] The wired unit is further preferably a sensor arranged on or in the sliding ring. The sensor is particularly preferably arranged in the sliding ring, in particular in a blind hole. The sensor is preferably a temperature sensor and is arranged in the sliding ring, allowing particularly precise temperature detection of the sliding ring.

[0020] Further preferably, the protective pin is designed such that the slotted area is larger in the axial direction than the head area of ​​the protective pin. The slotted area further preferably comprises, in particular, more than two-thirds of the total length of the protective pin in the axial direction.

[0021] Embodiments of the invention are described in detail below with reference to the accompanying drawings. In the drawing:

[0022] Fig. 1 is a schematic sectional view of a mechanical seal arrangement according to a first embodiment of the invention,

[0023] Fig. 2 is a schematic perspective view of a protective pin of the mechanical seal arrangement of Fig. 1,

[0024] Fig. 3 is a schematic sectional view along a longitudinal axis of the protective pin of Fig. 2,

[0025] Fig. 4 is a schematic sectional view of a mechanical seal arrangement according to a second embodiment of the invention, and

[0026] Fig. 5 is a schematic sectional view along the line VV of Fig. 4.

[0027] A mechanical seal arrangement 1 according to a first preferred embodiment of the invention is described in detail below with reference to Figs. 1 to 3.

[0028] The mechanical seal arrangement 1 seals a product area 16, which has a medium to be sealed, on a shaft 12 against an atmospheric area 17.

[0029] The mechanical seal assembly 1 comprises a mechanical seal 2 with a rotating seal ring 3 and a stationary seal ring 4. A sealing gap 5 is defined in a known manner between the sliding surfaces of the seal rings 3, 4. The rotating seal ring 3 is connected to the shaft 12 by means of a seal ring carrier 30 and rotates with it.

[0030] The stationary slide ring 4 is arranged on a stationary component 18, which is a housing. The stationary slide ring 4 is axially movable and is preloaded against the rotating slide ring 3 in an axial direction XX by means of a preloading element 11. As can be further seen from Fig. 1, a wired unit 7 is arranged in the stationary slide ring 4. The wired unit 7 comprises a sensor 70 and a cable 71. The cable 71 connects the sensor 70 to a measuring unit 10.

[0031] In this exemplary embodiment, sensor 70 is a temperature sensor configured to measure the temperature of the stationary slide ring during operation. Cable 71 is configured to transmit both electrical energy and information, in particular measured values, between sensor 70 and measuring unit 10.

[0032] The sensor 70 is arranged in a blind hole 41 at an acute angle a to the sealing gap 5. The cable 70 is led out of a radially outward-facing side of the stationary sliding ring at this acute angle a.

[0033] The mechanical seal assembly 1 further comprises a protective pin 6, which can be seen in detail in Figs. 2 and 3. The protective pin 6 has a slotted region 60 and a head region 63. As can be seen particularly from Fig. 1, the slotted region 60 is arranged in a groove 40 in the stationary seal ring 4. The groove 40 is a through groove extending in the axial direction XX on the outer circumference of the stationary seal ring 4. The width of the groove 40 is selected such that the slotted region 60 can be easily arranged in the groove 40 (see Fig. 1).

[0034] The head region 63 has a slightly larger diameter than the slot region 60. The head region 63 is arranged and fixed in the stationary component 18, e.g., by means of a press fit.

[0035] The slotted portion 60 has a first arm 61 and a second arm 62, as well as a recess 8. The recess 8 comprises a slot 80 formed between the first and second arms 61, 62, and a through-opening 81 provided in the head portion 63.

[0036] The slot 80 is formed between the arms 61, 62 as a slot that is completely continuous in the radial direction. Starting from the head region 63, the slot extends through to a free end of the slot region 60 and is open at the free end (cf. Fig. 2). The two arms 61, 62 therefore run parallel and are only fixed at the head region 63 and are otherwise not connected to one another in any way. As can be seen from Fig. 1, the cable 71 is led out of the stationary slide ring 4 in the region of the groove 40 and inserted directly into the recess 8, more precisely into the slot 80. The cable 71 is then led in an arc, first radially outwards out of the slot 80 and then inserted back into the slot 80 in front of the through-opening 81. The cable 71 is then led through the through-opening 81 into the housing and from there to the measuring unit 10.

[0037] Furthermore, a seal 9 is arranged in the housing 10 in order to seal the cable passed through the through opening 81 from the product area 16.

[0038] As can be seen from Fig. 1, the cable 71, starting from the stationary seal ring 4, is first guided through the product area 16 before being inserted into the stationary component 18. The cable is thus exposed to the conditions of the medium to be sealed, particularly potentially high temperatures and high pressures. Furthermore, the stationary seal ring 4, which includes the cable-connected unit 7, is arranged to be axially movable. The cable 71 can easily follow axial movements, particularly due to the cable 71 extending in a curved manner from the stationary seal ring 4, and in particular, without damage.

[0039] Thus, in particular, the cable 71 of the wired unit 7 is protected by the protective pin 6 and securely routed to the stationary component 18 and then through this to the measuring unit 10. This enables an optimal arrangement of the wired unit 7 in a sliding ring, whereby, in particular, the cable 71 can also be routed out of the sliding ring on a radial outer side. This allows the cable to be routed out in a smooth curve, so that even axial adjustment movements of the sliding ring can be carried out without damaging the cable.

[0040] Figures 4 and 5 show a mechanical seal assembly 1 according to a second embodiment of the invention. Identical or functionally identical parts are designated as in the first embodiment.

[0041] The second exemplary embodiment essentially corresponds to the first exemplary embodiment, wherein, in contrast to the first exemplary embodiment, in the second exemplary embodiment the cable 71 of the cable-connected unit 7 is guided out of the stationary sliding ring 4 in such a way that the cable 71 is arranged completely in the slot 80 between the two arms 61, 62. As a result, the cable 71 is guided in a straight line into the through-opening 81 in the head region 63 of the protective pin 6. As is clear from Fig. 5, the cable 71 is guided completely between the two arms 61, 62 in the slot region 60. In order to be able to follow larger axial movements of the stationary sliding ring 4, which is prestressed against the rotating sliding ring 3 by means of the prestressing element 11, the cable 71 can, for example, be guided in a wave-like manner in the slot region 60, without protruding radially outwards or radially inwards beyond the arms 61, 62.Thus, the cable 71 is particularly well protected against external influences, especially from product area 16, and can still follow axial movements.

[0042] The protective pin 6 of the second embodiment additionally has a torque transmission function. During operation, torque is transmitted from the stationary sliding ring 4 to the stationary component 18 via the protective pin 6, which serves as an additional torque transmission element. The protective pin 6 additionally has a cap 13, which is in direct contact with the walls of the groove 40 on the radial outer circumference of the stationary sliding ring 4. Thus, in addition to protecting the cable 71, the protective pin also has a torque-transmitting function. Otherwise, the second embodiment corresponds to the first embodiment, so reference can be made to the description given there.

[0043] List of reference symbols

[0044] 1 mechanical seal arrangement

[0045] 2 mechanical seals

[0046] 3 rotating slide ring

[0047] 4 stationary sliding ring

[0048] 5 Sealing gap

[0049] 6 protective pin

[0050] 7 wired unit

[0051] 8 Recess

[0052] 9 Seal

[0053] 10 measuring units

[0054] 11 Preload element

[0055] 12 Wave

[0056] 13 cap

[0057] 16 Product area

[0058] 17 Atmospheric area

[0059] 18 stationary component / housing

[0060] 30 sliding ring carriers

[0061] 40 grooves

[0062] 41 blind hole

[0063] 60 slot area

[0064] 61 first arm

[0065] 62 second arm

[0066] 63 Head area

[0067] 70 sensors

[0068] 71 cables

[0069] 80 slot

[0070] 81 Passage opening a acute angle

[0071] XX Axial direction

Claims

Claims 1. A mechanical seal arrangement, comprising: a mechanical seal (2) with a rotating slide ring (3) with a first sliding surface and a stationary slide ring (4) with a second sliding surface, which define a sealing gap (5) between the sliding surfaces, a wired unit (7) which is arranged on one of the slide rings, wherein the wired unit (7) has a cable (71) which is designed to supply electrical energy and / or to transmit information, and a protective pin (6) which is arranged on the slide ring having the wired unit and is designed to provide protection for the cable (71), wherein the protective pin (6) has a recess (8) through which the cable (71) fed from the slide ring provided with the wired unit is passed.

2. Mechanical seal arrangement according to claim 1, wherein the cable-connected unit (7) is arranged on the stationary slide ring (4) and the protective pin (6) is arranged between the stationary slide ring (4) and a stationary component (18).

3. Mechanical seal arrangement according to one of the preceding claims, wherein the cable (71) is fed from the sliding ring comprising the cable-connected unit (7) and is inserted directly into the recess (8) in the protective pin (6).

4. Mechanical seal arrangement according to one of the preceding claims, wherein the sliding ring having the cable-connected unit has a groove (40) on an outer circumference in which the protective pin (6) is arranged.

5. Mechanical seal arrangement according to one of the preceding claims, wherein the protective pin (6) comprises a slot region (60) and a head region (63), wherein the recess (8) in the slot region (60) comprises a slot (80).

6. Mechanical seal arrangement according to claim 5, wherein the slot (80) is open on one side in the axial direction (XX) and is designed as a radial through-slot, so that the slot region (60) has a first arm (61) and a second arm (62), between which the slot (80) is formed.

7. Mechanical seal arrangement according to claim 5 or 6, wherein the recess has a through-opening (81) in the head region (63) of the protective pin (6), such that the slot (80) merges directly into the through-opening (81) and the cable (71) is guided through the through-opening (81).

8. Mechanical seal arrangement according to one of the preceding claims, wherein the protective pin (6) is fixed in the stationary component (18).

9. Mechanical seal arrangement according to one of the preceding claims, wherein the sliding ring having the cable-connected unit (7) is prestressed in the axial direction (XX) by means of a prestressing element (11) and is arranged to be movable in the axial direction.

10. Mechanical seal arrangement according to one of the preceding claims, wherein the wired unit (7) comprises a sensor (70) which is arranged on or in the sliding ring.

11. Mechanical seal arrangement according to one of claims 5 to 10, wherein the cable (71) from the sliding ring having the cable-connected unit (7) is guided exclusively in the slot (80) of the protective pin (6) to the stationary component (18).

12. Mechanical seal arrangement according to one of the preceding claims, wherein the cable (71) is led out of the sliding ring having the cable-connected unit (7) on a radial outer side of the sliding ring at an acute angle to the sealing gap (5).

13. Mechanical seal arrangement according to one of the preceding claims, wherein the protective pin (6) is further configured to transmit a torque from or to the sliding ring comprising the cable-connected unit (7).

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