Contact part for electrically connecting end-face contact layers on the end faces of a plastic film capacitor winding of an encased electric single-phase or three-phase capacitor, and encased electric single-phase and three-phase capacitors comprising same

Abstract

The invention relates to a contact part (20) for electrically connecting end-face contact layers on the end faces of a plastic film capacitor winding (10) of an encased electric single-phase or three-phase capacitor to a terminal wire (18, 34) or a connecting wire, comprising a preferably flat contact support with a terminal region for contacting a terminal wire (18, 34) or a connecting wire; comprising at least one contact piece (26) with at least one contact tip, said contact piece (26) extending upwards or downwards from the contact support in a substantially vertical manner, in order to establish an electric connection to an end-face contact layer (12, 14) by pressing the contact tip into said end-face contact layer (12, 14); and comprising a penetration depth-limiting device for limiting the penetration depth of the contact tip or the contact tips in the end-face contact layer (12, 14). The invention also relates to encased single-phase and three-phase capacitors comprising said contact part.

Claims

1. An encased electric three-phase capacitor comprising a housing, a housing cover, three plastic film capacitor windings (10), which are arranged one above the other in the housing, are delta-connected to one another and whose end faces are each provided with an end-face contact layer (12, 14), and three terminal wires (18, 34, 44) which are passed through the housing cover, characterized in that the terminal wires (18, 34, 44) are electrically connected to the corresponding end-face contact layer (12, 14) of the capacitor windings (10) via a respective contact part (20, 21), wherein the contact parts (20, 21) are electrically connected to the respective corresponding end-face contact layer (12, 14) without the use of solder.

2. The encased capacitor as claimed in claim 1, characterized in that in each case one (20) of the contact parts (20, 21) is provided on the end faces of the uppermost and lowermost capacitor windings, and in each case one (21) of the contact parts (20, 21) is provided between the capacitor windings for making contact with each of the two adjacent end-face contact layers (12, 14), and a connecting wire (42) for electrically connecting the uppermost contact part (20) to the lowermost contact part (20) is provided.

3. The encased capacitor as claimed in claim 2, characterized in that the connecting wire (42) is electrically connected to the uppermost and lowermost contact parts (20, 20) by spot welding, crimping or soldering.

Description

(1) Further features and advantages of the invention are given in the attached claims and the description below, in which:

(2) FIG. 1 shows a longitudinal sectional view of an encased electric single-phase capacitor in accordance with a particular embodiment of the invention in a production stage;

(3) FIG. 2 shows a longitudinal sectional view of the encased capacitor shown in FIG. 1 during a later production stage;

(4) FIG. 3 shows a longitudinal sectional view of an encased electric three-phase capacitor in accordance with a particular embodiment of the invention in a production stage;

(5) FIG. 4 shows a longitudinal sectional view of the encased capacitor shown in FIG. 3 during a later production stage;

(6) FIG. 5 shows a side view (top) and a plan view from above (bottom) of a contact part in accordance with a particular embodiment of the invention; and

(7) FIG. 6 shows a side view (top) and a plan view from above (bottom) of a contact part in accordance with a further particular embodiment of the invention.

(8) FIG. 1 shows a plastic film capacitor winding 10, whose end faces are each provided with an end-face contact layer 12 and 14 consisting of zinc, for example. A terminal wire 18 extends from the top to the bottom through the hollow capacitor winding core 16. The upper end of the terminal wire 18 is passed through a housing cover after production of an encased electric single-phase capacitor with said plastic film capacitor winding 10.

(9) The lower end of the terminal wire 18 is electrically connected to a contact part 20 shown in FIG. 6 by spot welding, crimping or soldering. As can be seen from FIG. 6, the contact part 20 has a substantially ring-shaped, flat contact carrier 22 and a terminal lug 24 which extends inwards from the contact carrier 22 in the same plane. Contact pieces 26 each having a contact tip 28 and resting pieces 30 with resting areas 32, of which only some are identified, are arranged peripherally, equidistantly and alternately on the outer rim. The resting pieces each protrude to a lesser extent than the contact pieces. The contact part 21 shown in FIG. 5 differs from that 20 shown in FIG. 6 in that the contact pieces 26 and resting pieces 30 are not provided on one side but on both sides. Both the contact pieces 26 and the resting pieces 30 extend downwards on the outer rim, while the contact pieces 26 and the resting pieces 30 extend upwards on the inner rim.

(10) In FIG. 1, the contact part 20 shown in FIG. 6 is arranged in such a way that the contact pieces 26 and resting pieces 30 point upwards, i.e. towards the end-face contact layer 14.

(11) A contact part 20 shown in FIG. 6, but with downwards protruding contact pieces 26 and resting pieces 30, is likewise arranged above the upper end-face contact layer 12. This is electrically connected to a further terminal wire 34 by spot welding, crimping or soldering.

(12) Furthermore, in each case one upper insulating cap 36 and one lower insulating cap 38 are positioned already from above and from below. In addition, a holding ring 40 has already been arranged on the upper insulating cap 36.

(13) In FIG. 2, the upper contact part 20 and the lower contact part 20 have already been pressed against the respective end-face contact layer 12 and 14, to be precise in such a way that the contact tips 28 are pressed into the end-face contact layers 12 and 14, respectively, and therefore an electrical connection is achieved. As can be seen from a comparison of FIGS. 1 and 2, the insulating caps 36 and 38 in FIG. 2 are not only positioned but are pushed completely onto the plastic film capacitor winding. The pushing-in process can be performed during installation of the plastic film capacitor winding 10 in a housing (not shown) by corresponding compressive force on the upper insulating cap 36 and the lower insulating cap 38. In general, sheath insulation (not shown) is also provided.

(14) FIGS. 3 and 4 show the same for an encased electric three-phase capacitor. In order to produce an encased electric three-phase capacitor, three plastic film capacitor windings 10 are arranged in the form of a column one above the other. A contact part 20 shown in FIG. 6 with downwardly protruding contact pieces 26 and resting pieces 30 is arranged above the upper end-face contact layer 12 of the uppermost plastic film capacitor winding 10, and a contact part 20 as shown in FIG. 6 with upwardly protruding contact pieces 26 and resting pieces 30 is arranged below the lower end-face contact layer 14 of the lowermost plastic film capacitor winding 10. A contact part 21 as shown in FIG. 5 is arranged between the uppermost plastic film capacitor winding 10 and the central plastic film capacitor winding 10, and a contact part 21 as shown in FIG. 5 is likewise arranged between the central plastic film capacitor winding 10 and the lowermost plastic film capacitor winding 10. The uppermost contact part 20 is electrically connected to a terminal wire 18 by spot welding, crimping or soldering. Furthermore, a connecting wire 42 extends through the capacitor winding cores 16 of the three plastic film capacitor windings from the uppermost contact part 20 to the lowermost contact part 20. The connecting wire 42 is electrically connected both to the uppermost contact part 20 and to the lowermost contact part 20, in each case by means of spot welding, crimping or soldering.

(15) A terminal wire 20 extends from the top through the hollow capacitor winding core 16 of the uppermost plastic film capacitor winding 10 to the contact part 21 arranged between the uppermost plastic film capacitor winding 10 and the central plastic film capacitor winding 10 and is electrically connected thereto by spot welding, crimping or soldering.

(16) Finally, a terminal wire 44 extends from the top through the hollow capacitor winding core 16 of the uppermost plastic film capacitor winding 10 and the central plastic film capacitor winding 10 to the contact part 21 arranged between the central plastic film capacitor winding 10 and the lowermost plastic film capacitor winding 10. The terminal wire 44 is electrically connected thereto by spot welding, crimping or soldering.

(17) Precisely as in the embodiment shown in FIGS. 1 and 2, an upper insulating cap 36 and a lower insulating cap 38 are positioned at the top and at the bottom, respectively, wherein a holding ring 40 is also arranged on the upper insulating cap 36. Likewise precisely as in the embodiment shown in FIGS. 1 and 2, the contact tips 28 can be pressed into the respective end-face contact layers 12 and 14 by the upper and lower insulating caps 36 and 38 being pushed further onto the plastic film capacitor winding 10 by corresponding compressive force for example during installation in a housing (not shown). In the two embodiments, the plastic film capacitor windings 10 and contact parts 20 can be held in position by the holding ring 40 or a holding bead and a permanent electrical connection can thus be ensured.

(18) By virtue of the resting pieces 30 and the resting areas 32, the penetration depth is limited during fitting in order to prevent damage to the plastic film.

(19) The basic shape of the contact parts 20 and 21 can have very different geometry, wherein, owing to the round shape of the capacitor windings, a ring-shaped geometry appears to be particularly suitable, however.

(20) The contact parts 20 and 21 can be stamped parts. Depending on the intended use, the contact pieces 26 can be bent only to one side or else to both sides from the stamped part. In the case of the two-sided embodiment, two contact layers (winding bridges) positioned together can be electrically connected to one another to form a winding column without any additional metal connection. Metal with good electrical conductivity, in particular brass or copper, is preferred as the base material for the contact parts. A tin plating is advantageous, but not absolutely necessary, for improved contact-making.

(21) By virtue of the contacts disclosed above, the soldering operations which are time-consuming and difficult directly at the end-face contact layers (winding bridges) are no longer required. The size of the contact parts is dependent on the size and performance of the capacitor windings and the area of the end-face contact layers.

(22) The features of the invention disclosed in the description above, in the drawings and in the claims can be essential both individually and in any desired combinations for implementing the invention in its various embodiments.

LIST OF REFERENCE SYMBOLS

(23) 10 Plastic film capacitor winding

(24) 12, 14 End-face contact layers

(25) 16 Capacitor winding cores

(26) 18 Terminal wire

(27) 20 Contact parts

(28) 21 Contact parts

(29) 22 Contact carrier

(30) 24 Terminal lug

(31) 26 Contact pieces

(32) 28 Contact tips

(33) 30 Resting pieces

(34) 32 Resting areas

(35) 34 Terminal wire

(36) 36 Upper insulating cap

(37) 38 Lower insulating cap

(38) 40 Holding ring

(39) 42 Connecting wire

(40) 44 Terminal wire