EP0060289A1

EP0060289A1 - Reactive anode with consumption indicator and diving capsule for a heat probe.

Info

Publication number: EP0060289A1
Application number: EP81902648A
Authority: EP
Inventors: Werner Hossle
Original assignee: Individual
Current assignee: Sibylle Hoessle Te Berlijn Bondsrepubliek Duitsla
Priority date: 1980-09-17
Filing date: 1981-09-17
Publication date: 1982-09-22
Also published as: DE3035450C2; DE3035450A1; EP0060289B1; WO1982001017A1

Abstract

L'anode reactive est munie de deux pieces de contact (6, 4) qui sont accessibles depuis l'exterieur, qui traversent le joint filete, sont isolees l'une de l'autre et qui s'etendent dans une cavite a faces planes contenant la tige d'anode ou sont au moins en liaison spatiale avec elle. L'anode permet avec l'extremite accessible de l'exterieur le branchement d'un circuit de signalisation optique ou acoustique. L'extremite en liaison spatiale avec la cavite de tige d'anode agit comme commutateur electrique aussitot que la tige d'anode (10) est consommee. L'eau du recipient penetre dans la cavite, mouille ou enveloppe les contacts (4, 6) fermant ainsi le circuit.The reactive anode is provided with two contact pieces (6, 4) which are accessible from the outside, which pass through the threaded joint, are insulated from each other and which extend into a cavity with flat faces containing the anode rod or are at least in spatial connection with it. The anode allows with the end accessible from the outside the connection of an optical or acoustic signaling circuit. The end in spatial connection with the anode rod cavity acts as an electrical switch as soon as the anode rod (10) is consumed. Water from the container enters the cavity, wets or envelops the contacts (4, 6) thus closing the circuit.

Description

Cofer anode with consumption indicator and immersion sleeve for a heat sensor

The invention relates to a sacrificial anode with consumption indicator for the cathodic protection against corrosion of static or operating pressure water tanks and water heaters as well as for tanks of other, also electrically conductive media and has the purpose of simplifying sacrificial anodes with consumption indicator with regard to manufacture and their interchangeability on a container and - under Elimination of a moving display element of the consumption display - to adapt the installation, maintenance and control conditions in the application area mentioned in a practical manner.

The invention also relates to the structural connection of the sacrificial anode according to the invention with an immersion sleeve for receiving a so-called `` heat sensor '' in one piece, whereby the purpose is pursued, with a sacrificial anode and at least one heat sensor containers to be equipped with both control devices by means of a single screwing-in process o . Like. to be able to insert in one and the same container opening.

In the case of the already known sacrificial anodes with consumption indicator, the latter essentially consists of a pin-like organ which is longitudinally displaceable within a cavity of the anode and / or anode screw connection, which is moved towards the container when the anodic material is used up and when the container medium penetrates into the cavity and as Consumption signal from the front of the anode screw connection and thus emerges from the container. Sacrificial anodes of this type have proven themselves in many areas of application for cathodic container corrosion protection and have found their way into practice in a wide area. They are able to actuate remotely installed display means by mechanical or electrical means by means of the pen-like organ. From an economic point of view, such sacrificial anodes with consumption indicators are particularly disadvantageous in the standard factory equipment of small and medium-sized containers with such sacrificial anodes, since their production price for this container series article, for which a particularly favorable overall price must be sought, is in an unfavorable relationship. The display mechanism in the form of the pin-like, longitudinally displaceable member requires, in particular because of the necessary assembly activity, a higher manufacturing and thus a higher cost. It also has an expensive effect that, for design-related reasons, the anode rod and the anode screw connection containing the consumption indicator have to be connected to one another with the costly manual addition of a liquid sealant, which also leads to the application or maintenance disadvantage that the entire anode is used when the actual anocene rod is used up Consumption indicator must be replaced and not - in a far more economical way - only the anode rod. Finally, especially in the case of small containers, in particular water heaters, it is desirable to avoid parts that protrude from the container contour when the consumption is displayed, the meaning of which, when viewed briefly, in particular by laypersons, is not always recognized as the result of the display become.

In order to determine the consumption of Opferanoelen waiving _a, e in the anode integrated consumption indicator outside the container, an arrangement has become known in which by an electric measurement, for example current measurement, under comparison of anode volume values with corresponding electrical values over conclusions can be drawn about the state of consumption of the anode rod. Here, the sacrificial anode must be screwed into the container in an electrically insulated manner and, in order to maintain the function of the cathodic corrosion protection with the container, or the like via a detachable wire line. be connected.

If a measurement is to be made, the wire or the like. solved and interposed an electrical measuring device. Such a test procedure is cumbersome and time consuming. It can only be carried out by a specialist. In addition, a comparison table or the like is available for each anode size. with opposite anode volume values and electrical fourths.

Containers of the type mentioned generally have to be equipped with a heat control device, a heat sensor, if they contain heated media. Since such containers are usually also equipped with a sacrificial anode, manual interventions such as drilling, welding and the like are required at two points in the container with considerable expenditure of time and money. to make both devices in the container in their effective position. For example, for the heat sensor, a tube that is closed at one end, the immersion sleeve, is let in through a hole in the container and welded to the hole with its open end face, which is then or the like at its insertion opening by a stopper. heat sensor to be secured and for the sacrificial anode, a further hole is made in the container wall, which in most applications is to be provided with a threaded sleeve by welding. A juxtaposition of two identical work processes at different points in the container for a similar introduction of two control devices into the same container is highly uneconomical and contradicts this. contemporary efforts to rationalize and reduce costs.

The invention has for its object to eliminate the existing disadvantages in the use of the known sacrificial anodes with consumption indicator for water tanks and water heaters, in particular small and medium-sized tanks, and also to find a solution, while equipping both a tank with a sacrificial anode and a heat sensor To be able to mount control devices in one and the same container bore.

According to the invention, this is achieved with regard to the sacrificial anode in that, instead of a pin-like, longitudinally displaceable display element, two externally accessible, penetrating the anode screw connection, electrically insulated from one another and into an end-face cabbage space of the anode rod reaching into it, but at least spatially connected to it, contact parts are arranged, which make it possible to connect an optically and / or acoustically acting electrical signal device at their externally accessible ends, and which are spatially connected to their other, with the cavity of the anode rod . Ends act as an electrical switch as soon as the anode rod is used up, causing container water to penetrate into its cavity, wetting or surrounding the contact parts and thereby closing electrically.

The effectiveness of the switch bridge formed by container water depends on two criteria governed by the invention, which can be seen in the ratio of the electrical conductance of water: contact distance: test voltage and in the air column in the cabbage chamber, which counteracts the entry of water.

Based on a constant electrical conductivity of the water, a relatively small contact distance will have to be selected, for example, with a relatively low test voltage, which must be in the low-current range according to safety regulations, whereas a higher test voltage, for example, in favor of greater mechanical robustness of the contact ends of the contact parts, allows a larger contact distance. If a functional relationship between the test voltage and the contact distance cannot be maintained, the electrical conductivity of the water can be reduced by inserting a tablet speaking agents, such as salt, z.3. NaCl, be increased between the contact ends and the anode rod, which dissolves when water enters it.

Another criterion is the fact that the compressibility of the air depends on the pressure size of the container medium and the compression limit. When using the sacrificial anode for containers that are subject to a higher pressure (mostly containers with operating pressure), the contact ends may therefore have a calculable greater distance from the potential water entry point, whereas when using them for containers with low pressure (mostly containers with static pressure) ) the contact ends must be brought close to the potential water entry point. On the manufacturing side, the last-mentioned embodiment provides the need to shorten the iron core present in the anode rod within the cavity in the anode rod, so that in the case of containers with higher pressures, sacrificial anodes with the greater distance from the potential viasser entry point are to be preferred.

The electrical signal device can be connected to the contact ends accessible externally on a container either by a permanently connected circuit of an optical and / or acoustic signal fed by the secondary side of a mains transformer, or by means of a manual device to be pressed against the contact ends of the sacrificial anode, if necessary, with its connection contacts, with an optical and / or acoustic signaling device and its own battery power source, which corresponds to the mode of operation of an ohmmeter or a continuity tester. Such a manual device is particularly suitable for use by laypersons if a forced removal of contacts to counterpress the device is provided, which excludes contact removal errors, and because the meaning of the types of signals mentioned when they become effective cannot be misunderstood. The contact parts of the sacrificial anode can be designed from the outset for one or the other type of consumption display.

The principle according to the invention, while taking into account a releasable, self-sealing attachment of the anode rod to the anode screw connection, enables a very simple, economical and therefore inexpensive production of a copper anode suitable for water tanks and water heaters with a consumption display, which, in addition, lacks a movable display element of a high level

Robustness is and from this point of view it is particularly well suited for a less individualized mass installation in series containers ex works.

The sacrificial anode according to the invention also exists in its practical and basic training Consumption indicator in an anode screw connection produced by injection molding, preferably plastic injection molding, which is used to fasten the sacrificial anode in a container bore, in which the anode screw connection penetrates in the axial direction and protrudes from it at both ends - the one contact part, which is designed as a contact sleeve, is injected. as well as in a screw socket made exclusively of plastic, into which the other contact part designed as a contact pin is injected. The contact sleeve has an external thread at its one end pointing towards the anode rod for the anode rod to be screwed on, and an internal thread at its other end for screwing in the screw bushing carrying the contact pin. In the screwed-in state, the contact pin protruding into the contact sleeve is electrically insulated from the contact sleeve by the plastic screw bushing and is separated from the contact sleeve in its exposed area within the contact sleeve by a cylindrical air gap. The contact pin runs either to the end of the contact sleeve (at low container pressure) or (with uncut iron core of the anode rod and higher container pressure) so that there is a distance between the contact pin and the anode rod when the anode rod is screwed on. For the connection of a stationary signaling device, the contact pin can carry a thread and a nut for fastening a cable lug on its short end projecting outwards, whereas a further cable lug for connecting the contact sleeve to the screw socket of the contact pin is attached to the contact sleeve. When designing the contact parts for the only becarfs connection of a manual device, the cable lugs are eliminated. To push the one device contact, the end of the contact pin is flat or lenticular and the diameter of the contact sleeve is larger than the diameter of the screw socket, so that the other, approximately sleeve-shaped device contact can be placed over the screw socket until it comes into metallic contact with the contact sleeve. An equally good need-based connection of the manual device is achieved with the same contact means if - as above - a cable lug between the screw socket and threaded sleeve for producing an electrically conductive connection between the metallic unit contact sleeve-anode rod and the container wall is screwed, since the sleeve-shaped device contact when pushing the manual device through this contact to the contact sleeve.

The anode rod has on its one end face, in a manner known per se, a sack-shaped threaded bore into which the free end of the iron core of the anode rod projects. According to the invention, a circular groove is drawn on the anode end face around the blind bore, which carries an O-ring as a seal between the anode rod and the anode screw connection. Equipped in this way, both the anode rod and the anode screw connection can be easily and simply sealed and reliably sealed against pressurized container medium a new one can be replaced without having to unscrew the entire sacrificial anode from the container, and, if at the same time this can be connected to the cleaning of the container after loosening a front cover of the container. In addition, the sealability between the anode rod and the anode screw connection offers the economically prime advantage that after the anode rod has been used up, the anode screw connection and signal or contact transmitter no longer need to be thrown away, as was previously the case. Together with the extremely inexpensive manufacturability of the anode screw connection in injection molding processes, preferably plastic injection molding, while at the same time injecting the contact parts, this results in a sacrificial anode product with consumption display of high efficiency in production, assembly and maintenance - which is also possible - compared to the previous production method through machining and manual assembly still against the destruction of material and production values acc. the "disposable method".

In order to obtain a metallic connection between the anode rod and the container wall, which is required for the function of the cathodic corrosion protection and which is produced in conventional anodes by its metallic anode screw connection, the contact sleeve is connected to the container via a metallic line, as mentioned above, whereby the line can be attached to the container by means of a permanent magnet. This device required because of the plastic anode spoilage can be used for the control method specified in the "state of the art" by interposing an electrical measuring device, since for this purpose only the line on the contact sleeve needs to be detached, and provided that the progress of Consumption of anodic

Material and not just the final consumption should be determined.

From the practical, basic design of the sacrificial anode according to the invention with consumption indicator, there are several application requirements for the various types of container and anode spoilage, two of which, among other things. contain the solution to the further task according to the invention of being able to mount the sacrificial nano with consumption indicator and at least one heat sensor together in one and the same container bore.

According to this, in a first embodiment, the anode screw connection, consisting of a molded part, preferably a plastic molded part with an injected contact sleeve, is a screw nut, preferably a hexagon nut, with a threaded attachment, so that a sacrificial anode according to the invention which is equipped in this way can be screwed into a threaded sleeve which is customary on containers. Depending on the design of the contacts, the Anode consumption can be checked by a fixedly connected signal device or by a manual device. The metallic connection between the anode rod or contact sleeve and the container is produced by a metallic line.

In a second embodiment, such containers are taken into account which are provided with a simple through hole of smaller diameter in the container wall for the attachment of a sacrificial anode. For this purpose, the contact sleeve is injected - in a similar way to the anode screw connection - into a disk-shaped stop part made of plastic, the contact connection end of which, in this case having an external thread, is inserted from the inside of the container through the through hole of the container and from the outside with a threaded nut and more usual Locking and sealing washers are screwed on, whereby the screw socket with contact pin is already screwed to the contact sleeve if it has a smaller diameter than the contact sleeve, or is only screwed onto the contact sleeve after its attachment to the container by means of its contact sleeve if it has a larger diameter than the contact sleeve. Depending on the design of the connection contacts, the anode consumption can be controlled by a fixedly connected signal device or by a manual device. Since the contact sleeve and thus the anode rod is already through the metallic fastener gungsverschraubung is connected to the container, there is no special line connection required in the other embodiments for producing such a metallic connection.

In a third embodiment, the copper anode according to the invention with consumption indicator is basically formed like the first embodiment, but with a larger outside diameter of the anode screw connection and with the addition that now, parallel to the contact sleeve in the body of the anode screw connection, at least one immersion sleeve for receiving a heat sensor has a larger end face is injected, which corresponds approximately to the length of the anode screw connection and is designed at its end facing the interior of the container for a subsequent, also tubular extension. This configuration can preferably consist of an external thread at the end of the immersion sleeve and the like, or a ring-shaped separating notch. for easier removal of the closed end face of the immersion sleeve, after which the tubular extension is screwed onto the immersion sleeve. However, an extension can also be achieved by means of a plug connection. Depending on the design of the connection contacts, one or the other type of control mentioned in the first and second embodiment can also be considered here, as can the metallic line connection between the contact sleeve or anode rod and Be container wall acc. the first embodiment.

In a fourth embodiment, which essentially corresponds to the third embodiment with at least one injected and extendable immersion sleeve (and also to the first embodiment if an immersion sleeve is not injected), instead of an anode screw connection, a plastic end face cover of a container is the carrier of at least one injected one Immersion sleeve and / or the contact sleeve of the sacrificial anode, so that the immersion sleeve and sacrificial anode or only the sacrificial anode are installed in the container without a special contract when the end face cover is placed on the container and screwed to it. Depending on the design of the connection contacts, one or the other type of control mentioned in the first and second embodiment is also considered here, as is the metallic line connection between the contact sleeve or anode rod and the metallic part of the container. the first embodiment.

According to the fourth embodiment, the introduction of a container bore and the welding of a threaded sleeve into it for the assembly of the sacrificial anode and a further container bore together with welding work for the arrangement of the immersion sleeve and according to. the third embodiment saves the last-mentioned container processing. In the drawings sheet I and II, the invention is shown for example. They show

Fig. 1, the sacrificial anode with consumption display in, its practical basic education and gem. its first embodiment, in a central longitudinal section and with connections for a stationary 24 volt signal device and a connection for the metallic line connection to the container,

Fig. 2 is a plan view of the visible on the outside of the container front of the sacrificial anode acc. Fig. 1

Fig. 3 shows the sacrificial anode with regard to the contact sleeve and pin as in Fig. 1, but in a third embodiment with at least one injected immersion sleeve as well as with connections for a manual control device and a connection for the metallic line connection to the container, e.g. via a permanent magnet,

Fig. 4 is a plan view of the visible on the outside of the container end of the sacrificial anode with two in the container versehrau injection molded immersion sleeves acc. Fig. 3, Fig. 5, the sacrificial anode with respect to the contact sleeve and pin as Fig. 1, but in its second embodiment with a disk-shaped stop part made of plastic in place of an anode screw connection, for fastening by means of a screw nut in a simple container bore and with this simultaneously occurring metallic connection of the contact sleeve or anode rod and container wall, as well as with connection of a 24 volt signal device,

Fig. 6 provided with a threaded bore, a protective cap and a sealing ring (O-ring), partially shown in the longitudinal section end of the gem. 1 on the contact sleeve screwable anode bar, in a single illustration,

Fig. 7 is a plan view of the visible on the outside of the container front of the sacrificial anode acc. Fig. 5,

8 shows the sacrificial anode with regard to the contact sleeve and pin as in FIG. 1 and with regard to the immersion sleeve as in FIG. 3, but in its fourth embodiment as a container end cover made of plastic with an injected contact sleeve and at least one injected immersion sleeve, with a partial representation of the end cover and with a connection for a fixed 24 volt signal device and a connection for the metallic line connection with the. Container - and Fig. 9 is a plan view in section

Representation on the visible lid side after screwing the container front cover to the container acc. 'Fig. 8.

The four types of execution according to Fig. 1 to 5 and Fig. 7 to 9 can either with a fixed signaling device, such as be made up of the fixed cable lug connections 7 and 8, the display means 9 and a e.g. 24 volt power source (e.g. the secondary side of a mains transformer), acc. Fig. 1, 5 and 7 may be equipped or only with contact connections 4a and 6 or 8a in Fig. 3 for pushing a manual control device. 1, 3 and 8, container 3 and contact sleeve 6 must be connected to anode rod 10 by a metallic line 8a, the connection to a container 3 being able to exist in a permanent magnet.

The design of the contact parts in all types of construction consists of a contact sleeve 6 injected into the anode screw connection 1, 1 a or into the disk-shaped stop part 2 or into the front cover 17 of a container, and from a contact pin 4 which is axially penetrated by a screw bushing 5. supported and by screwing the screw sleeve 5 into a threaded bore of the Kentakthülse 6 while maintaining a cylindrical air gap to the inner wall of the contact sleeve 6 within the Contact sleeve 6 is arranged. The injection-molded parts 1, 1 a, 2 and 17 are preferably made of plastic and the screw bushing 5 is basically made of plastic or another insulating material because of its required electrical insulating effect between contact pin 4 and contact sleeve 6.

For releasably connecting the anode rod 10 to the anode screw connection 1, 1a and the others

Carriers 2 and 17 of the contact sleeve 6, the contact sleeve 6 is provided at its end facing the inside of the container with an external screw thread, and the end face of the anode rod 10 facing the contact sleeve 6 is provided with a corresponding threaded pocket hole and with a self-sealing so-called sealing ring located in a ring pocket around the threaded pocket hole. O-ring 12. This end of the anode rod 10 is also equipped in a known manner with a protective cap 11 which prevents the premature use of the anodic material in this area. The length of the threaded sleeve 6 depends on the length of the injection molded part 1, 1a, 2 or 17 carrying it. The length of the signal pin 4, however, depends on the pressure size of the container medium in question and should run to the end of the contact sleeve 6 at a relatively low pressure , since the air column located in the common interior of the contact sleeve 6 and the blind bore of the anode rod 10 by means of the consumption of the anode rod 10 via its Blind hole penetrating container medium or water is compressed in this case correspondingly less than at higher pressure, but the penetrating water can only reach the two contact parts 4 and 6 by simultaneous air compression, an electrically conductive connection being established by the water bridge. In the course of the contact pin 4 to the end of the contact sleeve 6 - as indicated above - it is necessary to shorten the iron core 10a of the anode rod 10 so that a distance visible in FIG. 1 is maintained between the contact pin 4 and the iron core 10a.

In a further use, this distance is used to insert a salt that has been properly tableted, e.g. NaCl, if the water entering after the consumption of the anode rod 10 is to be increased in its electrical conductivity, which takes place after the salt has been dissolved in the water. Since the cylindrical air gap between the contact sleeve 6 and the contact pin 4 is in a certain ratio to the conductance of normal water at a certain test voltage, the Viasser bridge would not be sufficient as an electrical cable bridge if the voltage was reduced or a different one at the place of use with a corresponding air gap predetermined voltage is found.

In this case, the conductivity of the water can be increased as described above. at correct dimensioning of the two components mentioned, an admixture of this type is not necessary. However, it can also be provided in principle by inserting the tableted salt before screwing on the anode rod 10, if one wishes to be certain of multiple security for each case.

The embodiment acc. 3 and 4 is additionally equipped with at least one immersion sleeve 13 for receiving a heat sensor, for which purpose the anode screw connection 1a has a correspondingly larger diameter than the basically identical design according to FIG. Fig. 1, which, like the training acc. Fig. 3. can be screwed into a threaded sleeve of a container 3, as can be seen, for example, from FIG. 1. The immersion sleeve 13 is shown in the drawing for the sake of better clarity in a length approximately corresponding to the anode screw connection la, also because this should be the length that is favorable for production for the injection process. In practical training there is a screw thread at the closed end of the immersion sleeve 13 and, preferably, an annular groove or the like running around. as preparation to be able to separate the bottom of the immersion sleeve more easily if necessary - for example to be able to saw it off, or the immersion sleeve 13 is also open from the outset at this end. For extension, extension tubes of different lengths can be provided, one end of which is closed and the other end of which has an internal thread, so that extension tube and Immersion sleeve 13 can be easily connected.

The embodiment acc. 8 and 9, also a combination of sacrificial anode and immersion sleeve 13, essentially corresponds to the embodiment according to FIG. 3 and 4. The two control devices, however, are injected in a front end cover 17 of a container during its manufacture in the plastic injection molding process and together form a structural unit. Contact devices 4, 5 and 6 of the anode rod 10 and immersion sleeve 13 are in this case mounted in a base-like cover reinforcement 17 b of the end cover 17. After screwing an anode rod 10 onto the contact sleeve 6, screwing corresponding extension tubes onto the immersion sleeve 13 and inserting the heat sensor and screwing the end cover 17 onto a container by means of screw holes 17a, both control devices are simultaneously introduced into the container without separate construction measures.

The embodiment acc. Fig. 5, the attachment to a container 3 only at a push-through hole of the container and by screwing using a screw nut 15 together with the usual sealing and locking washers, requires as an injection molded part, into which the contact sleeve 6 is injected, only an annular stop part 2 and an additional screw thread for the screw nut 15 on the outside pointing end of the contact sleeve 6. As shown, this embodiment is suitable for a fixed signal device.

In another training for implementation of the

.

Control by a manual device, or the like with their slip contacts. against the pin contact 4, preferably in its flat or lens form 4a, and must be pressed against the sleeve contact 6, the screw bushing 5 - in contrast to the drawing - has a smaller diameter than the contact sleeve 5 so that contact with the contact sleeve 6 is made possible at which slipping on the approximately sleeve-shaped contact of the device, the other contact arranged inside the approximately sleeve-shaped contact touches the contact pin 4 or its contact surface 4a.

Claims

Expectations :

1. Sacrificial anode with consumption indicator for water tanks and water heaters, characterized - indicates that the eefesticating means of the sacrificial anode have two insulated from one another on a container wall, the fastening means penetrating in the axial direction in the sense of electrical conductors in such an arrangement that their towards the inside of the container facing ends are sealed off from the container medium and against the ingress of container medium by the anode rod arranged on this end face of the fastening means, and in that at their other ends, which are accessible on the opposite end face of the fastening means, and with this part of the fastening means on the outside of the container are, an optical and / or acoustic signaling device that becomes effective in the way that the two contact parts penetrating the fastening means of the sacrificial anode are electrically connected in the event of a short circuit n Activate the signaling device by container medium that has penetrated when the seal is lifted.

2. sacrificial anode according to claim 1, g e k e n n z e i c h n e t by a fastening means formed as an anode screw connection (1) and a

Anode screw connection (1) penetrating in the axial direction and forming the contact part (6) by a screw bushing (5), which consists of insulating material, is carried and screwed into an internal thread of the contact sleeve (6) by means of the screw bushing (5) and forms the other contact part, contact pin (4) such that it is inside the contact sleeve (6), while maintaining a cylindrical air gap to the inner wall of the Kentakthülse (6), together with the contact sleeve (6) to the interior of the container (3), to the extent that it maintains an air gap to an anode rod (10) or its iron core (10a) that can be screwed on here , and in that on a screw thread of the contact sleeve (6) on its end facing the inside of the container end face with a threaded blind hole provided

Anode rod (10) is screwed on, and in that a groove with a G-ring (12) inserted therein is provided as a seal at the end of the anode around the threaded bag bore such that a seal of the contact pin (4) and contact sleeve ( 6) compared to the container medium and in that the other ends of the contact pin (4) and contact sleeve (6) accessible from the outside of a container (3) with connection means (7, 8) for a stationary signaling device (9) or with connection means (4a, 8a) are equipped for a manual signaling device.

3. sacrificial anode according to claim 1 and 2, characterized in that the contact sleeve (6) and contact pin (4) with screw socket (5) existing contact device (4,5,6) a disc-shaped stop part (2), which penetrates it, is held and the contact sleeve (6) has an external thread with a screw nut (15) at its end accessible from the outside of a container (3).

4. sacrificial anode according to claim 1 and 2, characterized in that within the anode screw (1a) parallel to the contact sleeve (6) at least one, at one end closed immersion sleeve (13) for receiving a so-called. "Heat sensor" is arranged in the In such a way that the open end of the immersion sleeve (13) is located on the end face of the anode screw connection (la) which is accessible from the outside of a container (3).

5. sacrificial anode according to claim 4, characterized by an open at both ends immersion sleeve (13) and by an on the inside of the container facing end of the immersion sleeve (13) attached, at its opposite end closed extension tube, such that immersion sleeve (13) and extension tube run on the same line of alignment.

6. sacrificial anode according to claim 4 and 5, characterized in that the arrangements of the contact device (4,5,6) and at least one immersion sleeve (13) with elimination of an anode ver screw (la) on a front cover (17) of a container (3) within a base-like cover reinforcement (17b) is made in such a way that when the front cover (17) is screwed to a container (3) the con

, clock device (4,5,6) protrude together with the anode rod (10) to be screwed onto the contact sleeve (6) and immersion sleeve (13) into the container (3), and in such a way that the end face cover (17) with contact device

(4,5,6) and immersion sleeve (13) form an integral part.

7. sacrificial anode according to claim 2, 4, 6 characterized in that the anode screw connection (2, 2 a) and the front cover (17) consist of plastic.

8. sacrificial anode according to claim 2, 4, 6 characterized in that the anode screw connection (2, 2 a) and the front cover (17) consist of metal.

9. sacrificial anode according to claim 2, 4.6, g e k e n n z e i c h n e t by a metallic line connection (8a) between contact sleeve (6) and container (3) and by a container connection of the line connection (8a) in the form of a permanent magnet (16).

10. sacrificial anode according to claim 2,3,4,6, characterized by a fit or the like from salt. tableted, in the through the opposite end faces of contact pin (4) and iron core (10a) of the anode rod (10) formed, limited space inserted part.