Patent Application
20140048394
This application claims the priority to Chinese Patent Application No. CN201210295622.2, filed Aug. 20, 2012, in the State Intellectual Property Office of P.R. China, which is hereby incorporated herein in its entirety by reference.
The present invention relates to a strip type off-circuit tap changer for a transformer.
Chinese Patent No. CN201126756Y discloses a strip type off-circuit tap changer, where a contact set has moving contacts and fixed contacts. The moving contact is clip-type, and two upper and lower moving contacts closely press and span over a fixed contact with a spring or a reed, such that when the switch is shifted, the upper and lower moving contacts slide on the fixed contact. The foregoing structure has the following shortcomings: the frictional resistance is great and has no handleability when the moving contacts slide on the fixed contact, the moving and the fixed contacts have great abrasion, which cannot avoid a transmission error in the operation positioning, and results in low operational reliability.
Therefore, a heretofore unaddressed need exists in the art to address the aforementioned deficiencies and inadequacies.
One of the objectives of the present invention is to provide a strip type off-circuit tap changer with reliable contact, correct positioning, and highly reliable operation, so as to overcome the shortcomings in the prior art.
In one aspect of the present invention, a strip type off-circuit tap changer includes an insulating rod and a support. An operation positioning device is arranged on the support, a rack mobile frame is disposed on the insulating rod, the rack of the rack mobile frame is engaged to a drive gear of the operation positioning device, columnar fixed contacts are longitudinally arranged at a spacing on the insulating rod, the rack mobile frame is connected to a moving contact frame, and a moving contact assembly is arranged on the moving contact frame and fits with the fixed contact on the insulating rod; the moving contact assembly is formed by an annular moving contact and an elastic pin, and the annular moving contact spans between two adjacent columnar fixed contacts.
In one embodiment, the elastic pin is arranged in the annular moving contact, the annular moving contact closely contacts the columnar fixed contact by imposing a radial elastic force on an inner ring, and the elastic pin is formed by a sliding pin and a return spring.
In one embodiment, the elastic pin is arranged out of the annular moving contact, the annular moving contact closely contacts the columnar fixed contact by imposing a radial elastic force on an outer ring, and the elastic pin is formed by a sliding pin and a return spring.
In one embodiment, a rear section of the sliding pin fits with a sliding hole of the moving contact frame, a front end of the sliding pin fits with the annular moving contact, and the return spring is sleeved outside the sliding pin.
In one embodiment, the moving contact frame is arranged with a cantilever bent downwards, and a sliding slot is opened at an inner side of the cantilever and fits with a lower end of the insulating rod in a sliding manner.
In one embodiment, the columnar fixed contact is in a shape of a cylinder or a flat column.
In one embodiment, the columnar fixed contacts longitudinally arranged at a spacing along the insulating rod is in a shape of a straight strip, and penetrate the insulating rod; the annular moving contact is disposed at an upper side of the columnar fixed contact, and the moving contact corresponds to the fixed contact up and down.
In one embodiment, the columnar fixed contacts longitudinally arranged at a spacing along the insulating rod are in a bent shape, and one end thereof is bent upwards after penetrating the insulating rod; the annular moving contact is disposed outside the end, bent upwards, of the columnar fixed contact, and the moving contact corresponds to the fixed contact front and back.
In one embodiment, the other end of the columnar fixed contact is a wiring column end.
In one embodiment, one to three sets of columnar fixed contacts are arranged, and each set is correspondingly disposed with a moving contact assembly, to form one to three sets of tap mechanisms.
The beneficial effects of the present invention are as follows: (1). the gear shifting of the moving contact is performed in a rolling displacement manner instead of the sliding displacement manner by using the annular moving contact, which not only reduces the frictional resistance during the moving of the moving contact, but also reduces the abrasion between the moving contact and the fixed contact, thereby prolonging the effective service life of the tap switch; (2). the annular moving contact spans between two adjacent columnar fixed contacts, so the moving contact and the fixed contact are reliably in contact with each other; the annular moving contact can be automatically homed, which achieves correct positioning; and since the moving contact has large traversing range when longitudinally moving during gear shifting and obvious handleability is achieved during the gear shifting, the operational reliability is high; and (3). the present invention has a simple and compact structure and is appropriately designed.
These and other aspects of the present invention will become apparent from the following description of the preferred embodiment taken in conjunction with the following drawings, although variations and modifications therein may be effected without departing from the spirit and scope of the novel concepts of the disclosure.
The accompanying drawings illustrate one or more embodiments of the disclosure and together with the written description, serve to explain the principles of the disclosure. Wherever possible, the same reference numbers are used throughout the drawings to refer to the same or like elements of an embodiment.
The present invention is more particularly described in the following examples that are intended as illustrative only since numerous modifications and variations therein will be apparent to those skilled in the art. Various embodiments of this invention are now described in detail in conjunction with the accompanying drawings. Referring to the drawings, like numbers indicate like components throughout the views.
In accordance with the purposes of this invention, as embodied and broadly described herein, this invention, in one aspect, relates to a strip type off-circuit tap changer. The embodiments of the present invention are described in detail below with reference to the accompanying drawings of
Referring to
When it is required to shift the gear, the operation positioning device 1 is activated to drive the drive gear 4 to rotate to drive the rack mobile frame 3 to longitudinally move; the rack mobile frame drives the moving contact frame 5 to move back and forth on the insulating rod, so as to drive the annular moving contact to roll on the columnar fixed contact, thereby implementing the gear shifting of the switch.
The strip type off-circuit tap changer according to a second embodiment of the present invention is shown in
The strip type off-circuit tap changer according to a third embodiment of the present invention is shown in
The strip type off-circuit tap changer according to a fourth embodiment of the present invention is shown in
The present invention recites, among other things, strip type off-circuit tap changer, which not only reduces the frictional resistance during the moving of the moving contact, but also reduces the abrasion between the moving contact and the fixed contact. The moving contact and the fixed contact are reliably in contact with each other, so that correct positioning is achieved, and handleability is achieved during gear shifting, thereby improving the operation reliability; and the switch has a simple and compact structure and is appropriately designed.
The foregoing description of the exemplary embodiments of the invention has been presented only for the purposes of illustration and description and is not intended to be exhaustive or to limit the invention to the precise forms disclosed. Many modifications and variations are possible in light of the above teaching.
The embodiments were chosen and described in order to explain the principles of the invention and their practical application so as to activate others skilled in the art to utilize the invention and various embodiments and with various modifications as are suited to the particular use contemplated. Alternative embodiments will become apparent to those skilled in the art to which the present invention pertains without departing from its spirit and scope. Accordingly, the scope of the present invention is defined by the appended claims rather than the foregoing description and the exemplary embodiments described therein.
| Number | Date | Country | Kind |
|---|---|---|---|
| 201210295622.2 | Aug 2012 | CN | national |
