FI61586C - FOER REFRIGERATION FOR USE OF DROSSLAR GENOM AENDRANDE AV DERAS LUFTGAP - Google Patents

Description

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JQTa lBJ (11) utlAccningsskrift 61bö6 C Patent granted 13 C6 1983 * rf? VT ^ Patent eeddelat ^ (51) Kv.Ht?/tntxi.3 H 01 F 41/02 FINLAND — FINLAND (21) Pattnttlhikamui - Pat «nt * m & knln | 752720 (22) HakambplM —AiwMutlngKlag 29-09.75 (23) AlkupMvi — GlklghMsdaf 29-09-75 (41) Tullut | ulklMlcal - Bllvlt offwitNg 31.03-76

After the administration of patents and claims (44) Date of issue. -

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Federal Republic of Germany-Förbundsrepubliken Tyskiand (DE) P 2UU6560.9 (71) Siemens Aktiengesellschaft, Berlin / Munchen, DE; Wittelsbacherplatz 2, D-8000 Munchen 2, Federal Republic of Germany-Förbundsrepubliken Tyskland (DE) (72) Michael Wirth, Traunreut, Federal Republic of Germany-Förbundsrepubliken Tyskland (DE) (7 * 0 Oy Kolster Ab (5 * 0 Method for changing their chokes) - Förfarande fj utning av drosslar genom ändrande av deras luftgap

The invention relates to a method for leveling an elongate choke, the choke having a sheath core surrounding the winding, consisting of an I-cross-sectioned core package without thinning and an E-cross-core core package, both of which consist of two longitudinally stacked core plates , wherein the I-core package is against the outer branches of the E-core package and the air gap is between it and the middle branch of the E-core package.

To compensate for the inductance of the choke, its air gap is usually changed. As a prerequisite for such variability, chokes have been developed which have a certain type of core cross-section and in which the core package is placed relative to the second package from the movable one. According to DE-A-23 23 266, the first rough adjustment in such a choke has already been carried out immediately before the welding of the two housing parts 61 586 2 surrounding the core. For fine adjustment, the air gap between the relative movable core packages was then reduced to level the choke to a sufficient length o-Salta by passing the pressure roll longitudinally over the choke.

However, this known method requires a cumbersome choke structure, which is poor, especially in view of the automated manufacturing method. However, a choke with a jacket core with I- and E-shaped core packages provides considerably better conditions for this purpose. Such a choke is disclosed, for example, in DE-A-21 49 079, · however, it has the disadvantage that the two core packages cannot be moved relative to each other. Thus, it balances the choke by filling its air gap with strips of insulating material provided with a ferromagnetic coating. A similar proposal is also made in the newer DE-A-23 25 703. DE-A-21 49 080 describes another leveling method which is also based on the notion that in the case of a jacket core with an E / I cross-section the leveling is achieved by introducing a ferromagnetic material into the air gap. In this case, a plastic containing a ferromagnetic filler was used for this purpose.

Finally, Finnish Patent Publication No. 53,763 describes a method for leveling a choke having an E / I cross-section, in which an I-shaped beam is permanently bent. However, the I-shaped yoke then has one or more weaknesses, for example in the form of a longitudinal groove in the choke; in addition, here the I-plates are bent simultaneously over the entire length of the choke until the desired impedance value is reached, whereby the equalization accuracy suffers.

However, these known proposals for leveling a choke with an E / I cross-section are too cumbersome; it is therefore an object of the invention to present a simpler and nevertheless accurate method for leveling such a choke without a weakening groove or other thinning in a skilled I-section core package.

A feature of the solution according to the invention according to the invention is, when using a method such as the one mentioned above, that the I-shaped core package is bent permanently and admittedly in a manner known per se by a longitudinal pressure of the choke 61 586 3, reducing the air gap to equalize the choke.

Thus, in the invention, the I-shaped core plates deform in the direction of their maximum moment of resistance. This is surprisingly possible with a relatively small force, since only a few plates have to be deformed at a time and a relatively small deformation distance is sufficient for each plate. The back-elasticity of the bent core plates also does not negatively affect the equalization event, since the consequent change in inductance is included in the measured value, resulting in a correspondingly much longer equalization distance in the longitudinal direction of the choke.

Only the back-elasticity of the last core plates immediately after the end of the equalization event results in a slight distortion of the desired inductance value. To avoid this, it is proposed in the further development of the invention that the equalization procedure is terminated only when the measured choke current is below a certain amount of the reference value. Thus, in the equalization procedure, a correspondingly lower current value or a higher inductance value is given as a "compensation". Thanks to the experimentally simple determination of this value, the special properties of a given choke structure, in particular their elastic behavior, can be taken into account to such an extent that the chokes can be adjusted within very narrow tolerance limits for a defined setpoint current. However, it is a prerequisite that the chokes are designed in such a way that their inductance remains below the desired setpoint, even in the event of an unfavorable tolerance.

The invention will be described in more detail with reference to a device for carrying out the method according to the invention and with reference to the drawings, in which Figure 1 shows a cross-section of the device along line II in Figures 2 and 3, Figure 2 shows a longitudinal section along lines II-II in III, and Fig. 4 shows a cross section of a choke to be leveled.

The body 4 of the device consists of a table 41 which, like the two partition walls 44, 45, is fixed between the two side walls 4 61586 42, 43. Attached to the spaced-apart transverse walls 44, 45 are two guide rods 46, 47 parallel to the table 41. A longitudinally moving carriage 3 is arranged on these handlebars by means of bearings 31, 32, 33 and 34. It is connected via a piston rod 51 to an actuator 5 connected to the body 4, which has a pneumatically or hydraulically driven cylinder, and on its upper side it supports a pressure source 2, which may likewise have a pneumatically or hydraulically driven cylinder with a piston. The pressure source 2 is connected via an associated piston rod 21 to a roller support 1 with two spaced apart rollers 11 and 12.

The leveling choke 6 preferably has the cross-sectional shape shown in Fig. 4 and thus consists of a two-part jacket core with E-shaped 61 and I-shaped 62 plates stacked in the longitudinal direction of the choke. The winding 64 is then located in the longitudinal direction of the choke 6 around the central branch 63 of the jacket core. The air gap 65 is located on the upper side between the central branch 63 and the I-shaped plates 62 which press against both outer branches. The choke is held together by a two-part sheet metal housing with a U-shaped lower part 66 and a flat upper part 67.

A recess for a choke 6 is formed in the table 41 of the device, which is adapted to the dimensions of the choke and which is adapted to the carriage 3 so that the longitudinal axis of the choke 6 is parallel to the carriage 3 and the rollers 11, 12 press the center of the top of the sheet metal housing 62 67 against.

The recess 71, 72 also has mating contacts (not shown) which are arranged to contact the connector contacts of the choke when the choke is placed in the recess. The automatic operation of the equalization method is controlled by a control device (not shown) which can receive a start signal from the pressure contact operated by the inductor. The control device then energizes the choke 6, compares the current thus generated with the set value, starts the pressure source 2 so that the rollers 11, 12 press against the choke 6 at a predetermined pressure and finally starts the drive 5 so that the rollers 11, 12 move longitudinally over the choke and thus permanently reduce the air gap for the distance traveled. As soon as the decreasing current reaches a certain limit value, the control device raises the roller carrier 1, returns the carriage 3 to the starting position shown in the figures and finally switches off the choke.