Convenient-to-install special resistor device for medium-voltage load

Abstract

The invention relates to the technical field of resistors, in particular to a convenient-to-install special resistor device for a medium-voltage load, which comprises a plurality of stacked resistor units, each resistor unit comprises a support frame and a plurality of resistor tubes, the periphery of each support frame is enclosed, the upper and lower parts of each support frame are open, and the resistor tubes are arranged in the support frames. Each resistor tube comprises an insulated supporting tube and a resistor strip, the resistor strip is an exposed metal strip, the resistor strip comprises a main body section and a connecting section which are integrally and continuously bent and sequentially alternate, the main body section keeps a linear shape by virtue of the strength of the main body section, the connecting section is in an arc shape, and two adjacent main body sections are connected through the connecting section and are arranged in a V shape; a plurality of positioning grooves are formed in the outer side of the supporting pipe, and the middle of each main body section is lapped and embedded in the corresponding positioning groove. Compared with the prior art, the heat dissipation performance is good, and the power density is higher. In addition, the side wall of the supporting frame is provided with the side air holes capable of being opened and closed, and therefore the inner side and the outer side of the supporting frame can be selectively communicated in the using process.

Description

Technical Field

[0001] The invention relates to the technical field of resistors, and in particular to a special resistor device for medium voltage loads which is easy to install. Background Art

[0002] The load box is a power detection device, which is mainly used to detect and maintain the load of generators, uninterruptible power supplies (UPS), batteries, and power transmission equipment. It is a tool for periodic testing and maintenance of generator sets and UPS uninterruptible power supplies. It can be used for load tests in hospitals, data centers, factories, and enterprises.

[0003] The existing load box has multiple resistor units stacked in layers, and each resistor unit generally uses a wire-wound resistor or a chip resistor. The wire-wound resistor includes a support rod and a resistance wire spirally wound outside the support rod. Since the resistance wire is tightly attached to the support rod, a large amount of heat from the resistance wire is transferred to the support rod, and the support rod needs to be cooled additionally. In addition, the resistance units on the lower layer have a greater obstruction to the resistance units on the upper layer, affecting the heat dissipation performance of the resistance units on the upper layer. During the research and development, the inventor found that it is necessary to improve the heat dissipation performance of the tubular resistor.

[0004] In addition, in the existing stacked resistor units, the peripheral seal is always intended to prevent air leakage, so that under the action of the fan, the heat in the box can only enter from the bottom of the frame and flow out from the top of the frame, and the hot air flows from bottom to top in a single channel. However, the inventors have found that the flow of a single channel is not the best option under special circumstances, such as different power operating states of the load, different continuous use time of the load, or different surrounding use environments. Summary of the invention

[0005] In view of all or part of the above-mentioned technical problems in the prior art, the present invention provides a special resistor device for medium voltage loads which is easy to install.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] A resistor device for medium-voltage loads that is easy to install is provided, comprising a plurality of resistor units arranged in a stacked manner, each resistor unit comprising a support frame surrounded by the circumference and opened at the top and bottom and a plurality of resistor tubes arranged in the support frame, each resistor tube comprising an insulated support tube and a resistor strip spirally wound outside the support tube, wherein the resistor strip is a bare metal strip, the resistor strip comprises a main section and a connecting section that are continuously bent in an integral manner and alternately in sequence, the main section maintains a straight shape by its own strength, the connecting section is in an arc shape, two adjacent main sections are connected via the connecting section and are arranged in a V shape with each other; a plurality of positioning grooves are provided on the outer side of the support tube, the middle part of each main section is overlapped and embedded in the positioning groove, and the elasticity of the connecting section enables the two adjacent main sections to clamp the support tube; the resistor strips of the plurality of resistor tubes are electrically connected to each other; a side air hole is provided on the side wall of the support frame, the side air hole is fitted with a plug to block the side air hole; the plug can be withdrawn, so that the inside and outside of the support frame can be selectively connected or blocked.

[0008] As a further optional solution, the groove wall of the positioning groove is adapted to fit with the outer wall of the main body segment.

[0009] As a further alternative, the cross section of the resistor strip is circular, polygonal or elliptical.

[0010] As a further optional solution, the thickness of the resistor strip is set uniformly.

[0011] As a further optional solution, the thickness of the main body section is set unevenly, gradually becoming thinner from the part overlapping the support pipe towards the connecting section.

[0012] As a further alternative, the diameter of the connecting section is smaller than that of the main body section.

[0013] As a further optional solution, lead rings are provided at both ends of the resistor bar; the support frame is provided with lead terminals penetrating the side walls, and the lead rings are connected to the lead terminals.

[0014] As a further option, the support tube is a porcelain tube or a mica tube.

[0015] As a further optional solution, a screw is passed through the support tube, and the screw passes through both ends of the support tube and passes outside the support frame; the two ends of the screw passing through the support tube are sleeved with ceramic rings and nuts, and the two ends of the ceramic ring respectively press against the inner walls of the support tube and the support frame, and the nut is threadedly connected to the screw and presses against the outer wall of the support frame.

[0016] As a further optional solution, the side wind holes are arranged at the junction of two adjacent upper and lower support frames, a plurality of side wind holes are arranged at intervals along the junction line, and a plurality of plugs are independent of each other or connected into a whole.

[0017] Beneficial effects of the present invention:

[0018] The present invention is a medium-voltage load-specific resistor device that is easy to install. Compared with the prior art, the resistor bar is wound on a support tube to ensure stable strength, and the support tube is provided with a positioning groove to prevent adjacent main body sections of the resistor bar from being close together, thereby ensuring product reliability. The resistor bar is directly exposed to the air for heat dissipation, which has a higher power density. A larger heat dissipation space is left between the resistor bar and the support tube, and the diameter of the support tube can be made thinner, so that the wind resistance of the lower resistor unit to the upper resistor unit is small. Without the shell and magnesium oxide insulation powder of the existing load resistor tube, the factors affecting the insulation and failure problems of the resistor are reduced to a lower level. There is no need to consider the high-temperature insulation failure problem of magnesium oxide powder, and there is no need to consider problems caused by shell corrosion, etc.

[0019] Furthermore, the side walls of the support frame are provided with side air holes that can be opened and closed, so that the inside and outside of the support frame can be selectively connected during use. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a three-dimensional diagram of the stacked wire-wound resistor in the embodiment.

[0021] Figure 2 It is a schematic diagram of the stacked wirewound resistor in the embodiment after the plug is pulled out.

[0022] Figure 3 Schematic diagram of the structure of the resistor tube in the embodiment, in which the ceramic ring and nut are simplified.

[0023] Figure 4 It is an exploded view of the resistor tube in the embodiment, with the resistor bar hidden.

[0024] Figure 5 It is a side view of the resistor tube in the embodiment.

[0025] Figure 6 Schematic diagram of the resistor bar in the embodiment.

[0026] Reference numerals:

[0027] Resistor tube 1;

[0028] Support tube 11, positioning groove 111;

[0029] The resistor bar 12, the main body section 121, the connecting section 122, and the lead ring 123;

[0030] Screw 13, ceramic ring 14, nut 15.

[0031] Support frame 2, lead terminal 21, side air hole 22, plug 23. DETAILED DESCRIPTION

[0032] The following will be combined with the accompanying drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. In the absence of conflict, the following embodiments and features in the embodiments can be combined with each other.

[0033] The stacked wire wound resistor of this embodiment is as follows Figures 1 to 6 As shown, it includes a plurality of resistor units arranged in layers, each resistor unit includes a support frame 2 surrounded by the circumference and opened at the top and bottom, and a plurality of resistor tubes 1 arranged in the support frame 2, each resistor tube 1 includes an insulated support tube 11 and a resistor bar 12 spirally wound outside the support tube 11, the resistor bar 12 is a bare metal bar, and the resistor bar 12 includes a main section 121 and a connecting section 122 that are continuously bent and alternated in sequence, the main section 121 relies on its own strength to maintain a straight line, the connecting section 122 is arc-shaped and has a certain elasticity, and two adjacent main sections 121 are connected via the connecting section 122 and arranged in a V shape with each other; a plurality of positioning grooves 111 are opened on the outer side of the support tube 11, and the middle part of each main section 121 is overlapped and embedded in the positioning groove 111, and the elasticity of the connecting section 122 allows the adjacent two main sections 121 to clamp the support tube 11. Three resistor units are shown in the figure, and other numbers of stacking can be adopted according to needs. The resistor bars 12 of multiple resistor tubes 1 of the same resistor unit are electrically connected to each other, or different resistor bars 12 of different resistor units are electrically connected to each other, and can actually be connected in series or in parallel as needed.

[0034] Specifically, the groove wall of the positioning groove 111 is adapted to fit with the outer wall of the main body section 121 .

[0035] Specifically, the cross section of the resistor bar 12 is circular, but can actually be changed to a polygon or an ellipse.

[0036] Specifically, the thickness of the resistor bar 12 is uniformly set. In practice, the thickness of the main section 121 can be non-uniformly set, gradually becoming thinner from the part overlapping the support tube 11 to the direction close to the connecting section 122. Further, the diameter of the connecting section 122 can be changed to be smaller than that of the main section 121, which is convenient for bending. The straight metal strip is first elongated and reduced in diameter at a preset position (corresponding to the connecting section 122), and then bent to form the resistor bar 12. Specifically, lead rings 123 are provided at both ends of the resistor bar 12; the support frame 2 is provided with a lead terminal 21 that penetrates the side wall, and the lead ring 123 is connected to the lead terminal 21.

[0037] Specifically, the support tube 11 is a porcelain tube or a mica tube.

[0038] Specifically, the support tube 11 is penetrated by a screw 13, which passes through both ends of the support tube 11 and passes outside the support frame 2. The two ends of the screw 13 passing through the support tube 11 are sleeved with a ceramic ring 14 and a nut 15, the ceramic ring 14 is in a convex shape, which is sleeved outside the screw 13 and abuts against the end surface of the support tube 11, and the nut 15 and the screw 13 are threadedly matched with each other, and the ceramic ring 14 and the nut 15 are used to fix the entire resistor tube 1 to the support frame 2.

[0039] In this embodiment, a side wind hole 22 is opened on the side wall of the support frame 2, and the side wind hole 22 is adapted to be equipped with a plug 23 to block the side wind hole 22; the plug 23 can be pulled out, so that the inside and outside of the support frame 2 can be selectively connected or blocked.

[0040] Specifically, the side air holes 22 are arranged at the junction of two upper and lower adjacent support frames 2, and multiple side air holes 22 are arranged at intervals along the junction line. Multiple plugs 23 are independent of each other and can be pulled out or inserted individually, or multiple plugs 23 are connected as a whole and all plugs can be pulled out or inserted at one time. In practice, the plug can also be plugged in and out electrically, for example, by cylinder drive. The figure shows that the side air holes 22 and the plug 23 are cross-shaped, but they can actually be changed to other shapes.

[0041] During normal use, the plug 23 blocks each side air hole 22, so that multiple support frames 2 are enclosed, and hot air can only enter from the bottom and flow out from the top. In special circumstances, when it is necessary to connect the inside and outside of the support frame 2, just pull out the plug 23. For example, after the load has been running for a long time, when the heat between the layers of the resistance unit is too large, the side air holes 22 can be opened to allow part of the heat to flow out through the side air holes 22 and remain in the box body to avoid excessive accumulation of heat between the layers. After the power is reduced and the temperature between the layers drops to the preset temperature, the side air holes 22 can be blocked. For example, when the ambient temperature around the load box is low and the air volume is large, the side air holes 22 can be opened, and the heat in the box body enters the inner side of the support frame 2 from the bottom and sides at the same time, and is discharged from the top, thereby improving the heat exhaust efficiency.

[0042] In the description of the present invention, it is obvious that the described embodiments are only some embodiments of the present invention, rather than all embodiments. The components of the embodiments of the present invention generally described and shown in the drawings herein can be arranged and designed in various different configurations.

[0043] Therefore, the above detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making creative efforts are within the scope of protection of the present invention.

[0044] In the description of the present invention, it should be noted that the terms "middle", "upper", "lower", "horizontal", "inner", "outer", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, or the positions or positional relationships in which the product of the invention is usually placed when in use. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0045] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "disposed", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection. It can be a mechanical connection or an electrical connection. It can be directly connected or indirectly connected through an intermediate medium, and it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

Claims

1. A medium voltage load dedicated resistor device that is easy to install, comprising a plurality of resistor units arranged in a stacked manner, each resistor unit comprising a support frame (2) surrounded by a circumference and open at the top and bottom, and a plurality of resistor tubes (1) arranged in the support frame (2), each resistor tube (1) comprising an insulating support tube (11) and a resistor strip (12) spirally wound outside the support tube (11), wherein: The resistor bar (12) is a bare metal bar. The resistor bar (12) comprises a main body section (121) and a connecting section (122) which are continuously bent and alternately formed in an integral manner. The main body section (121) maintains a straight line shape by its own strength. The connecting section (122) is in an arc shape. Two adjacent main body sections (121) are connected via the connecting section (122) and are arranged in a V shape. A plurality of positioning grooves (111) are formed on the outer side of the support tube (11). The middle part of each main body section (121) is overlapped. Embedded in the positioning groove (111), the elasticity of the connecting section (122) enables two adjacent main sections (121) to clamp the support tube (11); the resistance bars (12) of the plurality of resistance tubes (1) are electrically connected to each other; the side wall of the support frame (2) is provided with a side air hole (22), and the side air hole (22) is adapted to be equipped with a plug (23) so as to plug the side air hole (22); the plug (23) can be removed, so as to selectively allow the inside and outside of the support frame (2) to be connected or blocked.

2. A medium voltage load dedicated resistor device that is easy to install according to claim 1, characterized in that: The groove wall of the positioning groove (111) is adapted to fit the outer wall of the main body section (121).

3. A medium voltage load dedicated resistor device that is easy to install according to claim 1, characterized in that: The cross section of the resistor strip (12) is circular, polygonal or elliptical.

4. A medium voltage load dedicated resistor device that is easy to install according to claim 1, characterized in that: The thickness of the resistor strip (12) is evenly arranged.

5. The medium voltage load dedicated resistor device that is easy to install according to claim 1 is characterized by: The thickness of the main body section (121) is unevenly arranged, and gradually becomes thinner from the portion overlapping the support tube (11) toward the direction close to the connecting section (122).

6. A medium voltage load dedicated resistor device that is easy to install according to claim 1, characterized in that: The diameter of the connecting section (122) is smaller than that of the main body section (121).

7. A medium voltage load dedicated resistor device that is easy to install according to claim 1, characterized in that: Lead rings (123) are provided at both ends of the resistor bar (12); the support frame (2) is provided with lead terminals (21) penetrating the side wall, and the lead rings (123) are connected to the lead terminals (21).

8. The medium voltage load dedicated resistor device that is easy to install according to claim 1 is characterized by: The support tube (11) is a porcelain tube or a mica tube.

9. The medium voltage load dedicated resistor device that is easy to install according to claim 1 is characterized by: The support tube (11) is provided with a screw rod (13), which passes through both ends of the support tube (11) and passes outside the support frame; the two ends of the screw rod (13) passing through the support tube (11) are sleeved with a ceramic ring (14) and a nut (15), the two ends of the ceramic ring respectively abut against the inner wall of the support tube and the support frame, and the nut is threadedly connected to the screw rod and abuts against the outer wall of the support frame.

10. The medium voltage load dedicated resistor device that is easy to install according to claim 1 is characterized by: The side air holes (22) are arranged at the junction of two upper and lower adjacent support frames (2), a plurality of side air holes (22) are arranged at intervals along the junction line, and a plurality of plugs (23) are independent of each other or connected to form a whole.

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