Capacitor fastening

A capacitor fastening for fastening a capacitor to a panel, whereby the capacitor, when mounted in place, is positioned in the panel, fastened at its lower part. The capacitor fastening includes a retainer in the panel at the mounting point of the capacitor for preventing lateral movement of the capacitor in at least one selected direction; a tightening plate arranged above the panel and to be fastened to the panel, which tightening plate has a hole substantially corresponding to the diameter of the capacitor above the mounting point of the panel; and a wedge between the panel and the tightening plate for tightening the retainer of the panel and the edge of the hole in the tightening plate from opposite directions against the capacitor.

RELATED APPLICATION

This application claims priority under 35 U.S.C. §119 to Finnish Patent Application No. 20116116 filed in Europe on Nov. 11, 2011, the entire content of which is hereby incorporated by reference in its entirety.

FIELD

The disclosure relates to capacitor fastening for fastening a capacitor to a panel, whereby the capacitor, when mounted in place, can be positioned in the panel and fastened there at its lower part. The capacitor fastening includes a retainer in the panel at the mounting point of the capacitor for preventing lateral movement of the capacitor in at least one selected direction, and a tightening plate arranged above the panel and to be fastened to the panel. The tightening plate has a hole substantially corresponding to the diameter of the capacitor above the mounting point of the panel. A wedge is provided between the panel and the tightening plate for tightening the capacitor in place between the panel and the plate.

BACKGROUND INFORMATION

Cylindrical capacitors, for example, can be difficult to fasten because their geometry usually does not contain actual fastening features. Another issue can arise from high manufacturing tolerances of capacitors.

A known fastening method includes a bolt attached to an end facing the capacitor terminals for fastening the capacitor to a plate underneath by a screw. Other known fastening methods include different band and clip fastenings.

From the point of view of mounting, the above fastening methods can be difficult and time-consuming. Because there are two mounting directions, one on the terminal side and the other on the side of the bottom screws, the part assembly may have been turned around during mounting. Many fastenings may be needed, whereby volume of the mounting space is wasted.

SUMMARY

A capacitor fastening is disclosed for fastening a capacitor, the capacitor fastening comprising a panel for fastening to a lower part of the capacitor, a retainer at a mounting point of the capacitor in the panel for preventing a lateral movement of the capacitor in at least one selected direction, a tightening plate for arranging above the panel and for fastening to the panel, the tightening plate having a hole substantially corresponding to a diameter of the capacitor above the mounting point of the panel, and a wedge between the panel and the tightening plate for tightening the capacitor in place between the panel and the plate, wherein the wedge includes wedging pins in the panel and corresponding wedging holes in the tightening plate, which, when brought into co-operation, are arranged to tighten the retainer of the panel and an edge of the hole of the tightening plate in opposite directions around the capacitor in directions perpendicular to an axial direction of the capacitor.

DETAILED DESCRIPTION

An exemplary embodiment of the disclosure can provide a new capacitor fastening wherein the wedge includes wedging pins provided in the panel and corresponding wedging holes provided in the tightening plate, the pins and holes, when in co-operation, being arranged to tighten the retainer of the panel and the edge of the tightening plate hole in opposite directions about the capacitor, perpendicular to an axial direction of the capacitor.

The disclosure is based on mounting the capacitor by two cross-tightening cellular plates. The plates tighten around the capacitor in a radial direction and, in addition, in a tightening step they wedge the capacitor tightly to the panel or the bottom plate.

The panel retainer can be formed of a curved collar corresponding to the shape of the outer surface of the capacitor rising from the panel, the collar extending on a pre-determined distance around the capacitor. Correspondingly, the hole in the tightening plate can be provided with a downward collar that is on an opposite side of the capacitor in relation to the collar in the panel and extends on a predetermined distance around the capacitor.

The panel retainer can also be formed of a recess made to the panel and matching the shape of the capacitor bottom.

In that case, an appropriate fastening of the panel and the tightening plate is realized by, for example, a screw fastening, which can act at the same time as a tightening mechanism for the wedge.

In an exemplary embodiment of the disclosure, capacitors with bottom screws are not needed and hence there are fewer parts to be mounted. In addition, all mounting works can be carried out from one direction without having to turn and rotate the capacitor system. Moreover, increased useful space is gained in the modules where the capacitors are placed, and the space can be utilized for larger capacitance or by using fewer capacitors of high capacitance, thus allowing cost savings. For example, when a capacitor with 20% more volume is used instead of a 100 mm high capacitor, four capacitors from a set of 20 may be left out. A capacitor without bottom screws can be less expensive, which allows capacitance to be increased by 20% at the same cost.

With reference to the drawings, a capacitor fastening of the disclosure is shown for fastening a capacitor1to a panel2, the capacitor1, when mounted in place, being fastened to the panel2by its lower portion.

The panel2of the drawings can be used for fastening a plural number of capacitors1. The capacitors1to be fastened are of a type that has no bottom screw, or at least none is needed.

The panel2has upright curved collars3matching the shape of an outer surface of the capacitor1. The collars extend on a predetermined distance around the capacitors1when the capacitors1are in place. These collars3can act as retainers for preventing lateral movement of the capacitors1in a predetermined selected direction at their mounting points. The direction can be the same in the fastening point of each capacitor1.

Above the panel2there is provided a tightening plate4to be attached thereto. The plate has holes5substantially corresponding to the diameters of the capacitors1above corresponding mounting points of the panel2. The holes5can have downward collars6on the opposite side of the capacitors1in relation to the collars3of the panel2and they extend on a predetermined distance around the capacitors when the capacitors1are in place. The collars6are not indispensable for the tightening in place of the capacitors1but they can protect the isolations of the capacitors1. For this purpose the material of the collars6can be, for example, vulcanized rubber.

For the capacitors1placed between the panel2and the tightening plate to be fastened and tightened in place between the panel2and the tightening plate4, wedges7and8can be arranged between the panel2and the tightening plate4for tightening the collars3of the panel2and the holes5of the tightening plate4and their collars6from opposite directions against the capacitors1in directions perpendicular to their axial directions.

The wedges7and8include a sufficient number of wedging pins7in the panel2and corresponding wedging holes8in the tightening plate4, and when made to co-operate, these are arranged to tighten the panel2and the tightening plate4in opposite directions around the capacitors1. For the mounting of the fastening plate4, it is desirable that the wedging pins7are conical at least in their upper part. When screw fastening is used to fasten the panel2and the tightening plate4together, the screw fastening can act at the same as a fastening mechanism for the wedges7and8. In this case the screw fastening can include screws9that penetrate the tightening plate4and attach to the panel2. In this example, and with particular reference toFIG. 4, the tightening plate4moves to the right when the screws9are tightened and forces the capacitor1to tighten between the collar3of the panel2and the collar6of the tightening plate4. In this case also the collar3of the panel2comes into contact with the bottom surface of the tightening plate4, and the collar6of the tightening plate4substantially comes into contact with the top surface of the panel2, the collars3and6extending in each case on a distance of 180°, at the most, around the capacitor1.

The panel2of the disclosure can be formed for fastening a desired number of capacitors, the size of the capacitors1to be fastened being also freely selectable.

The above description of the disclosure is only intended to illustrate the basic idea of the disclosure. A person skilled in the art may, however, implement the basic idea of the disclosure in a variety of ways. The disclosure and its embodiments are thus not restricted to the examples described above, but they may vary within the scope of the attached claims. Hence the retaining means of the bottom plate, for example, are formed of a recess matching the shape of the capacitor bottom.