EP4670467A1

EP4670467A1 - FLOATING MOUNTING STRUCTURE AND FREQUENCY CONVERTER

Info

Publication number: EP4670467A1
Application number: EP23929456.4A
Authority: EP
Inventors: Ming Zhou; Kai Kai LI; Jing Bo HU; Zi Ang ZHAO
Original assignee: Siemens AG; Siemens Corp
Current assignee: Siemens AG; Siemens Corp
Priority date: 2023-03-31
Filing date: 2023-03-31
Publication date: 2025-12-31
Also published as: WO2024197873A1; CN120513696A

Abstract

In the embodiments of the present invention, a floating mounting structure and a frequency converter are provided. The floating mounting structure comprises a plate body and at least one nut wherein the plate body is provided thereon with at least one nut placing recess, and the nut placing recess is provided therein with a clamping part wherein the at least one nut placing recess is corresponding one-to-one to the at least one nut, the nut placing recess has a shape matched with a bottom contour of the nut such that the nut will not rotate when the nut is placed in the nut placing recess and is thread-connected with a first screw; and the nut is provided, on its inner wall, with a clamping groove which is matched with the clamping part, and the clamping groove has such a dimension that when the nut is clamped on the clamping part by the clamping groove and when the nut is not in threaded connection with the first screw, there is a space for vertical floating of the nut. According to the embodiments of the present invention, the busbar and the PCB are rigidly connected, and thus the deformation of the PCB can be mitigated or even eliminated.

Description

Floating Mounting Structure and Frequency Converter

TECHNICAL FIELD

The present invention relates to the technical field of frequency converters, and specifically to a floating mounting structure and a frequency converter.

BACKGROUND OF THE INVENTION

In a design of a frequency converter, as the frequency converter has a high power, the current entering the basbar after rectification for the input AC is high. In order to prevent faults (such as heat generation) due to poor connection and in order to ensure a reliable connection between the busbar and the printed circuit board (PCB) , it is necessary to form a rigid connection between the busbar and the PCB. However, when the busbar is rigidly connected with the PCB, the PCB may be deformed due to the connection stress.
SUMMARY OF THE INVENTION
In the embodiments of the present invention, a floating mounting structure and a frequency converter are provided wherein a busbar and a PCB are rigidly connected, and thus the deformation of the PCB can be mitigated or even eliminated.
According to a first aspect, in an embodiment of the present invention, a floating mounting structure is provided, comprising a plate body and at least one nut wherein the plate body is provided thereon with at least one nut placing recess, and the nut placing recess is provided therein with a clamping part wherein the at least one nut placing recess is corresponding one-to-one to the at least one nut, the nut placing recess has a shape matched with a bottom contour of the nut such that the nut will not rotate when the nut is placed in the nut placing recess and is thread-connected with a first screw; and the nut is provided, on its inner wall, with a clamping groove which is matched with the clamping part, and the clamping groove has such a dimension that when the nut is clamped/snap-fit on the clamping part by the clamping groove and when the nut is not in threaded connection with the first screw, there is a space for vertical floating of the nut.
According to a second aspect, in an embodiment of the present invention, a frequency converter is provided, comprising a PCB, a busbar provided above the PCB, and a floating mounting structure provided below the PCB, a first screw screwed in from a side of the busbar is in threaded connection with and locked with a nut on the floating mounting structure, achieving rigid connection of the busbar and the PCB; wherein the floating mounting structure is the floating mounting structure as provided in the first aspect.
The floating mounting structure and the frequency converter as provided in the embodiments of the present invention, individually or in combination, can have at least the following technical effects:
(1) The busbar and the PCB can be rigidly connected by the nut and the first screw. Moreover, each nut placing recess is provided therein with a clamping part and each nut is provided therein with a clamping groove, and the clamping part and the clamping groove are matched with each other. Therefore, the clamping part and the clamping groove can be used to clamp/snap-fit and connect the nut within the nut placing recess. Moreover, the clamping/snap-fitting and connecting operation of the nut and the nut placing recess may be completed by the supplier. Thus, during assembling of the frequency converter, it is not necessary to assemble the nut with respect to the plate body, and the efficiency for assembling the frequency converter can be improved. There is a certain limitation to the dimension of the clamping groove such that on one hand, the nut can be clamped/snap-fit on the clamping part, and on the other hand, there can be a space for vertical floating of the nut before the nut is in threaded connection with the first screw. That is, when the nut is clamped/snap-fit on the clamping part by the clamping groove, the nut can move vertically. Thus, during threaded connection and locking of the nut and the first screw, the deformation of the PCB due to the stress can be mitigated or eliminated.
(2) In an embodiment, the circular ring is formed by combination of a plurality of arched bodies, with a gap between any two adjacent arched bodies. Thus, when the clamping part is clamped/snap-fit and connected to the clamping groove, as the clamping part is configured with spaced pieces and thus is somewhat flexible, the clamping/snap-fitting and connection of the clamping part with respect to the clamping groove is very smooth and can be achieved without a too-high force. Moreover, the possibility of damage of the clamping part due to the clamping/snap-fitting and connection operation of the clamping part with respect to the clamping groove is lowered.
(3) In an embodiment, the first layer structure may have an outer diameter dimension less than that of the second layer structure such that when the floating mounting structure and the first screw are used to rigidly connect a busbar and a PCB of a frequency converter, a Cu post between the busbar and the PCB is used for limiting a floating-up amplitude of the nut. That is, when the busbar and the PCB are rigidly connected by means of the floating mounting structure and the first screw, the Cu post between the busbar and the PCB is above the second layer structure. Thus, it is possible to prevent the nut from detaching from the plate body, and the floating-up space of the nut is limited.
(4) In an embodiment, the first layer structure may have a height such that when the nut is locked with the first screw, a tail of the first screw will not enter the second layer structure. That is, after the nut is in threaded connection with the first screw for locking, the tail of the first screw will not enter the second layer structure, without damage to the clamping part.
DESCRIPTION OF THE DRAWINGS
In order to explain the technical solutions in the embodiments of the present invention or in the prior art more clearly, the figures necessary to be used for description in the embodiments or in the prior art will be briefly introduced as below. Apparently, the figures for the description below are for some embodiments in the present invention. Based on these figures, those skilled in the art can obtain other figures without any inventive work.
Figure 1 is a structural diagram of a plate body in a floating mounting structure in an embodiment of the present invention.
Figure 2 is a section view of a nut in an embodiment of the present invention.
Figure 3 is a diagram of an embodiment of the present invention after a clamping part on a plate body is clamped/snap-fit and connected with a nut.
Figure 4 is a diagram of an embodiment of the present invention after a busbar, a Cu post, a first screw, a PCB and a floating mounting structure are assembled.
Reference numerals:
DESCRIPTION OF EXEMPLARY EMBODIMENTS
In order to make the objective (s) , technical solutions and advantages of embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be described clearly and completely hereinafter in connection with the figures in the embodiments of the present invention. Apparently, the described embodiments are some embodiments in the present invention, rather than all embodiments. Any other embodiments obtained based on the embodiments in the present invention by those skilled in the art without any inventive work will fall within the protection scope of the present invention.
In a first aspect, in an embodiment of the present invention, a floating mounting structure is provided. Referring to figures 1-3, the floating mounting structure comprises a plate body 10 and at least one nut 20 wherein:
the plate body 10 is provided thereon with at least one nut placing recess 11, and the nut placing recess 11 is provided therein with a clamping part 12 wherein the at least one nut placing recess 11 is corresponding one-to-one to the at least one nut 20, the nut placing recess 11 has a shape matched with a bottom contour of the nut 20 such that the nut 20 will not rotate when the nut 20 is placed in the nut placing recess 11 and is thread-connected with a first screw; and
the nut 20 is provided, on its inner wall, with a clamping groove 22a which is matched with the clamping part 12, and the clamping groove 22a has such a dimension that when the nut 20 is clamped/snap-fit on the clamping part 12 by the clamping groove 22a and when the nut 20 is not in threaded connection with the first screw, there is a space for vertical floating of the nut 20.
In practical application circumstances, the busbar is above the PCB and the floating mounting structure is below the PCB. A first screw is screwed in from a side of the busbar, and after passing through the PCB, is in threaded connection with and locked with a nut on the floating mounting structure, thus achieving rigid connection of the busbar and the PCB.
For example, referring to figure 1, the plate body 10 is provided thereon with six nut placing recesses 11, and thus there are six nuts 20. The bottom contour of the nut 20 has a hexagonal shape and thus the nut placing recess 11 also has a hexagonal shape, and the nut 20 and the nut placing recess 11 are matched in dimension with each other. When the nut 20 is placed within the nut placing recess 11, the nut 20 can not rotate. Therefore, during locking of the nut with the first screw, the nut can be locked with respect to the first screw only by rotation of the first screw. It is understandable that if there is no limitation to the nut 20 by the nut placing recess 11, during locking of the first screw, the nut 20 would rotate and thus it is necessary to hold the nut 20. In contrast, in the embodiment (s) of the present invention, with the limitation by the nut placing recess 11, it is thus not necessary to hold the nut 20.
Each nut placing recess 11 is provided therein with a clamping part 12 and each nut 20 is provided therein with a clamping groove 22a, and the clamping part 12 and the clamping groove 22a are matched with each other. Therefore, the clamping part 12 and the clamping groove 22a can be used to clamp/snap-fit and connect the nut 20 within the nut placing recess 11. Moreover, the clamping/snap-fitting and connecting operation of the nut 20 and the nut placing recess 11 may be completed by the supplier. Thus, during assembling of the frequency converter, it is not necessary to assemble the nut 20 with respect to the plate body 10, and the efficiency for assembling the frequency converter can be improved.
Further, there is a certain limitation to the dimension of the clamping groove 22a such that on one hand, the nut 20 can be clamped/snap-fit on the clamping part 12, and on the other hand, there can be a space for vertical floating of the nut 20 before the nut 20 is in threaded connection with the first screw. That is, when the nut 20 is clamped/snap-fit on the clamping part 12 by the clamping groove 22a, the nut 20 can move vertically. Thus, during threaded connection and locking of the nut 20 and the first screw, the deformation of the PCB due to the stress can be mitigated or eliminated.
As can be seen, the busbar and the PCB are rigidly connected by means of the floating mounting structure as provided in the embodiments of the present invention, and thus the deformation of the PCB can be mitigated or even eliminated.
In an embodiment, referring to figure 3, the clamping part 12 may have an outer contour in a shape of a circular ring, and it is possible to provide a flange 12a at an upper rim of an outer wall of the circular ring.
That is, the clamping part has a structure of a circular ring, and a flange is provided at an upper rim of an outer wall of the circular ring. Thus, the clamping part can be clamped/snap-fit within the clamping groove by the flange. Specifically, the flange may be provided continuously along a complete circle of the upper rim, or may be provided discontinuously along the circle of the upper rim.
Further, the circular ring may be formed by combination of a plurality of arched bodies, with a gap between any two adjacent arched bodies.
For example, referring to figure 1, the structure of the circular ring is formed by combination of four arched bodies, with a gap between any two adjacent arched bodies. Thus, when the clamping part is clamped/snap-fit and connected to the clamping groove, as the clamping part is configured with spaced pieces and thus is somewhat flexible, the clamping/snap-fitting and connection of the clamping part with respect to the clamping groove is very smooth and can be achieved without a too-high force. Moreover, the possibility of damage of the clamping part due to the clamping/snap-fitting and connection operation of the clamping part with respect to the clamping groove is lowered.
In an embodiment, the nut may have a double-layer structure wherein a first layer structure of the double-layer structure has a shape of a hollow cylinder and is provided on its inner wall with a thread, and a second layer structure of the double-layer structure has an outer contour matched with the shape of the nut placing recess and is provided on its inner wall with the clamping groove.
For example, referring to figure 2, the first layer structure 21 is an upper layer structure of the nut and is provided on its inner wall with a thread. Thus, the threaded connection between the nut 20 and the first screw 30 can be achieved. The second layer structure 22 is a lower layer structure and is provided on its inner wall with the clamping groove 22a, also called groove. The clamping part 12 can be clamped/snap-fit within the clamping groove 22a. The second layer structure 22 has an outer contour in a hexagonal shape, consistent with that of the nut placing recess 11. As can be seen from figure 2, the end portion of the clamping groove has a hook-like shape such that the clamping part can be clamped/snap-fit into the clamping groove. However, it is difficult to remove the clamping part from the clamping groove, and thus the mounting stability between the nut and the plate body can be improved.
Further, the first layer structure may have an outer diameter dimension less than that of the second layer structure such that when the floating mounting structure and the first screw are used to rigidly connect a busbar and a PCB of a frequency converter, a Cu post between the busbar and the PCB is used for limiting a floating-up amplitude of the nut.
In practical circumstances, the busbar, the Cu post, the PCB and the above plate body are arranged in sequence from top to bottom. The first screw is screwed in from a side of the busbar, passes through the busbar, the Cu post and the PCB, and then is in threaded connection with the nut on the plate body for locking.
For example, referring to figure 2, the first layer structure 21 has a shape of a circular cylinder, and its outer diameter is less than that of the hexagonal shape of the second layer structure. Thus, when the busbar and the PCB are rigidly connected by means of the floating mounting structure and the first screw, the Cu post between the busbar and the PCB is above the second layer structure. Thus, it is possible to prevent the nut from detaching from the plate body, and the floating-up space of the nut is limited.
In an embodiment, referring to figure 4, the first layer structure may have a height such that when the nut is locked with the first screw, a tail 31 of the first screw will not enter the second layer structure.
That is, the first layer structure has a relatively large height. Thus, after the nut is in threaded connection with the first screw for locking, the tail of the first screw will not enter the second layer structure, without damage to the clamping part.
In an embodiment, referring to figure 1, the plate body may be further provided thereon with a screw hole 13 by which a second screw can connect the plate body 10 with the PCB of the frequency converter.
That is, by the screw hole on the plate body and the second screw, the plate body is connected with the PCB. In practical circumstances, first, the plate body is connected with the PCB by means of the screw hole on the plate body and the second screw, and then the busbar, the Cu post and the PCB are assembled by the nut and the first screw.
In an embodiment, the plate body may be made of plastic.
It is understandable that if the plate body is made of plastic, the weight of the plate body can be reduced, and the plate body of plastic is more beneficial for integrated molding of the nut placing recess and the clamping part.
In a second aspect, in an embodiment of the present invention, a frequency converter is provided. Referring to figure 4, the frequency converter comprises a PCB 60, a busbar 40 provided above the PCB, and a floating mounting structure provided below the PCB, wherein a first screw 30 screwed in from a side of the busbar is in threaded connection with and locked with a nut 20 on the floating mounting structure, achieving rigid connection of the busbar 40 and the PCB 60; wherein the floating mounting structure is the floating mounting structure as provided in the first aspect.
That is, the busbar and the PCB can be rigidly connected by the nut and the first screw. Moreover, each nut placing recess is provided therein with a clamping part and each nut is provided therein with a clamping groove, and the clamping part and the clamping groove are matched with each other. Therefore, the clamping part and the clamping groove can be used to clamp/snap-fit and connect the nut within the nut placing recess. Moreover, the clamping/snap-fitting and connecting operation of the nut and the nut placing recess may be completed by the supplier. Thus, during assembling of the frequency converter, it is not necessary to assemble the nut with respect to the plate body, and the efficiency for assembling the frequency converter can be improved. There is a certain limitation to the dimension of the clamping groove such that on one hand, the nut can be clamped/snap-fit on the clamping part, and on the other hand, there can be a space for vertical floating of the nut before the nut is in threaded connection with the first screw. That is, when the nut is clamped/snap-fit on the clamping part by the clamping groove, the nut can move vertically. Thus, during threaded connection and locking of the nut and the first screw, the deformation of the PCB due to the stress can be mitigated or eliminated. As can be seen, in the frequency converter as provided in the embodiments of the present invention, the busbar and the PCB can be rigidly connected, and the deformation of the PCB due to the stress can be mitigated or eliminated during connection.
In an embodiment, referring to figure 4, a Cu post 50 may be further provided between the busbar 40 and the PCB 60, and the Cu post 50 has a structure of a hollow cylinder. The first screw 30 can pass through the busbar 40, a hollow portion of the Cu post 50 and the PCB 60, and then be in threaded connection with the nut 20 on the floating mounting structure.
That is, the Cu post is provided between the busbar and the PCB. The Cu post has a structure of a hollow cylinder. The first screw can pass through a hollow portion of the Cu post and the PCB, and then be in threaded connection with the nut on the plate body for locking. The Cu post has the structure of the hollow cylinder to thus facilitate connection of the nut with the first screw.
The embodiments in the present description are described in a gradually progressive manner. The same or similar portions between different embodiments can be referred to each other. Each embodiment emphasizes in explaining the difference (s) with respect to other embodiment (s) . In particular, as the apparatus/device embodiments are substantially similar to the method embodiments, the description thereof is relatively simple, and the description of the method embodiments may be referred to for the related portions.
With the above-described specific embodiments, the purposes, technical solutions and beneficial effects of the present invention are further explained in detail. It should be understood that the above description is only for specific embodiments in the present invention, not for defining the protection scope of the present invention. Any variation, equivalent substitution or improvement made based on the technical solutions of the present invention will fall within the protection scope of the present invention.

Claims

A floating mounting structure, characterized in that it comprises a plate body and at least one nut wherein

the plate body is provided thereon with at least one nut placing recess, and the nut placing recess is provided therein with a clamping part wherein the at least one nut placing recess is corresponding one-to-one to the at least one nut, the nut placing recess has a shape matched with a bottom contour of the nut such that the nut will not rotate when the nut is placed in the nut placing recess and is thread-connected with a first screw; and

the nut is provided, on its inner wall, with a clamping groove which is matched with the clamping part, and the clamping groove has such a dimension that when the nut is clamped on the clamping part by the clamping groove and when the nut is not in threaded connection with the first screw, there is a space for vertical floating of the nut.
The floating mounting structure according to claim 1, characterized in that the clamping part has an outer contour in a shape of a circular ring, and a flange is provided at an upper rim of an outer wall of the circular ring.
The floating mounting structure according to claim 2, characterized in that the circular ring is formed by combination of a plurality of arched bodies, with a gap between any two adjacent arched bodies.
The floating mounting structure according to claim 1, characterized in that the nut has a double-layer structure wherein a first layer structure of the double-layer structure has a shape of a hollow cylinder and is provided on its inner wall with a thread, and a second layer structure of the double-layer structure has an outer contour matched with the shape of the nut placing recess and is provided on its inner wall with the clamping groove.
The floating mounting structure according to claim 4, characterized in that the first layer structure has an outer diameter dimension less than that of the second layer structure such that when the floating mounting structure and the first screw are used to rigidly connect a busbar and a PCB of a frequency converter, a Cu post between the busbar and the PCB is used for limiting a floating-up amplitude of the nut.
The floating mounting structure according to claim 4, characterized in that the first layer structure has a height such that when the nut is locked with the first screw, a tail of the first screw does not enter the second layer structure.
The floating mounting structure according to claim 1, characterized in that the plate body is further provided thereon with a screw hole by which a second screw can connect the plate body with the PCB of the frequency converter.
The floating mounting structure according to claim 1, characterized in that the plate body is made of plastic.
A frequency converter, characterized in that it comprises a PCB, a busbar provided above the PCB, and a floating mounting structure provided below the PCB, wherein a first screw screwed in from a side of the busbar is in threaded connection with and locked with a nut on the floating mounting structure, achieving rigid connection of the busbar and the PCB; wherein the floating mounting structure is the floating mounting structure according to any one of claims 1-8.
The frequency converter according to claim 9, characterized in that a Cu post is further provided between the busbar and the PCB, the Cu post has a structure of a hollow cylinder, the first screw can pass through the busbar, a hollow portion of the Cu post and the PCB and then be in threaded connection with the nut on the floating mounting structure.