JPH0441578Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a plug-in contact device installed in a control panel such as a control center.

[Conventional technology]

An example of a general structure of the control center is shown in FIG. 5, and a sectional view thereof taken along the line 2 is shown in FIG. In these figures, 1 is a side plate, and the interior thereof is divided into a unit chamber 10 and a wiring duct chamber 11 by an internal frame 2 and a separator 3. The front sides of the unit room 10 and the wiring duct room 11 are closed with a unit room door 4 and a duct room door 5, respectively. A unit frame 6 is housed in the unit chamber 10 so as to be removable in the front-back direction, and an insulating support base 7 to which a U-shaped contact blade 8 is attached is provided on the back side of the unit frame 6. When the unit frame 6 is pushed in, the contact blade 8 comes into contact with the vertical bus bar 9, and power is supplied to the control equipment mounted on the unit frame 6.

An example of a conventional mounting structure for the contact blade 8 and the insulating support 7 is shown in FIG. In this example, the contact blade 8 is fixed by placing the terminal plate 15 at the bottom of the contact blade 8, inserting the screw 13 from the opposite wall of the insulating support base 7, and tightening the screw to the female screw provided on the terminal plate 15. .

As described above, in the conventional contact device, the contact blade is directly or indirectly fixed to the insulating support base, and therefore fine adjustment is required for positioning the contact.

If this fine adjustment is not perfect, the contact blade 8 will come into contact with only one side of the vertical bus bar 9 and the load current will be applied only to one side of the contact blade 8, as shown in FIG. This may lead to an accident due to the contact parts becoming overheated.

As a method for solving these problems, there is a plug-in terminal device described in Japanese Utility Model Publication No. 53-38864. This is done by providing a through hole with steps at predetermined locations in the insulating base, inserting a U-shaped metal fitting into the through hole, and inserting this into the stepped part of the through hole. Further, the conductive wire led out from the other end of the through hole is fixed to the bottom of the insertion fitting, and the insertion fitting uses its U-shaped bent shoulder as a fulcrum to adjust the conductor plate thickness. A play space is provided between the insertion fitting and the through hole so that it can move only in one direction.

[The problem that the idea attempts to solve]

However, in the case of this structure, it is necessary to install a spring-like locking piece to prevent the insert fitting from coming off between the step provided inside the through hole of the base and the bottom inner surface of the insert fitting. A jig or the like is required for mounting, and the workability is also poor. Additionally, if the centers of the contact blade and the vertical generatrix are not aligned, unreasonable force will be applied to the locking piece that clamps the contact blade, leaving permanent distortion and causing contact failure, and the same problem as above. The current carrying capacity was insufficient, and there was a risk of an accident due to heat generation at the contact part.

Further, once the contact blade is attached, the locking piece engages with the stepped portion of the through hole due to its spring properties, making it difficult to remove the insertion fitting. Furthermore, since the structure is such that the conductive wire is directly fixed to the bottom of the insert by spot welding or the like, it is not possible to connect the conductor after the insert is attached to the insulating base.

The present invention was devised in view of these conventional problems, and provides a plug-in contact device such as a control center that is self-centering with respect to the vertical generatrix, with good assembly workability. The purpose is to have a structure that is easy to attach and detach.

[Means to solve the problem]

In order to achieve this purpose, the plug-in contact device such as a control center of the present invention is a contact device in which a U-shaped contact blade that contacts a conductor such as a vertical busbar is attached to an insulating support base with a screw. A screw hole provided in the mounting wall of the insulating support base for inserting a screw has a length longer than the depth of the screw hole,
A spacer having an outer diameter smaller than the inner diameter of the screw hole is inserted, and the U-shaped contact blade is freely attached to the insulating support base by a screw passed through the spacer.

〔Example〕

Hereinafter, the present invention will be specifically explained based on embodiments shown in the drawings. FIG. 1 is a sectional view showing an embodiment of the contact device according to the present invention, FIG. 2 is a rear view of an insulating support, and FIG. 3 is a sectional view taken along the - line in FIG. 1. Note that the same components as those in the conventional configuration are designated by the same reference numerals and the description thereof will be omitted.

As shown in these figures, in this embodiment, the screw hole of the insulating support 7 is made larger in diameter than the example shown in FIG. A spacer 12 having an outer diameter smaller than the inner diameter of the terminal plate is fitted, and is screwed onto the conductor plate 15 using the terminal plate tightening screw 13. In the figure, 16 is a washer. A contact blade 8 is fixed in advance to one end of the conductor plate 15 by a contact blade fixing screw 17. Furthermore, a cable connection screw 14 is attached to the other end of the conductor plate 15 to connect a conductor wire for wiring with equipment mounted on the unit frame 6 (see FIG. 6).

In the contact device configured in this way, between the spacer 12 and the screw hole of the insulating support base 7,
It has play in the radial and longitudinal directions. This play is set, for example, to about ±1 to 1.5 mm.
By doing so, the center of the contact blade 8 and the vertical generatrix 9
Even if the contact blade 8 is misaligned with the center of the vertical generatrix 9, the contact blade 8 moves to align with the center of the vertical generatrix 9, as shown in FIG. Therefore, the same contact pressure is applied to both blades of the contact blade 8, and it is no longer possible to apply current to only one side. Since this self-aligning structure does not use any urging means such as springs, the structure is simple and the problem of deterioration such as fatigue of the springs is solved.

[Effect of idea]

As explained above, in the present invention, a spacer having an outer diameter longer than the depth of the screw hole and smaller than the inner diameter of the screw hole is inserted into the screw hole provided in the mounting wall of the insulating support base. The U-shaped contact blade is freely attached to the insulating support by a screw passed through the spacer. As a result, the tip of the contact blade can move freely within a predetermined range, so even if the center of the contact blade is misaligned with the vertical generatrix due to mechanical dimensional errors or installation errors, the contact blade can be adjusted by the self-aligning action. coincides with the center of the vertical generatrix. This eliminates the need for fine adjustment work such as positioning the contact blades, and facilitates assembly of the unit frame. Also,
Compared to conventional systems that use springs or the like for self-alignment, problems such as spring fatigue are eliminated, and accidents caused by this can be prevented. Furthermore, since there is no need to make fine adjustments for each unit frame, the compatibility of unit frames is improved.

[Brief explanation of drawings]

Fig. 1 is a sectional view showing an embodiment of the contact device of the present invention, Fig. 2 is a rear view thereof, and Fig. 3 is a -
Figure 4 is a cross-sectional view showing the state of self-alignment when the center of the vertical generatrix is misaligned, Figure 5 is a front view of a general control center,
FIG. 6 is an enlarged sectional view taken along the - line in FIG.
FIG. 7 is a sectional view showing an example of a conventional contact device. 1... Side plate, 2... Internal frame, 3... Separator, 4... Unit chamber door, 5... Duct chamber door, 6
... Unit frame, 7 ... Insulation support stand, 8 ... Contact blade, 9 ... Vertical bus bar, 10 ... Unit chamber, 11
...Wiring duct room, 12...Spacer, 13...
...Terminal board tightening screw, 14...Cable connection screw, 15...Terminal board, 16...Washer, 17...Contact blade fixing screw.

Claims (1)

[Scope of utility model registration request] In a contact device in which a U-shaped contact blade that contacts a conductor such as a vertical bus bar is attached to an insulating support with screws, a screw hole provided in the mounting wall of the insulating support to insert the screw is provided. A spacer having an outer diameter longer than the depth of the screw hole and smaller than the inner diameter of the screw hole was inserted, and the U-shaped contact blade was attached to the insulating support base in a floating state by a screw passed through the spacer. A plug-in contact device for a control center, etc., characterized by: