CN2332115Y

CN2332115Y - Marmen self-restored safety unit for telephone exchange centre

Info

Publication number: CN2332115Y
Application number: CN 98224256
Authority: CN
Inventors: 金浩
Original assignee: Individual
Current assignee: Individual
Priority date: 1998-06-11
Filing date: 1998-06-11
Publication date: 1999-08-04
Anticipated expiration: 2008-06-11

Abstract

The utility model belongs to the field of communication equipment, which is especially suitable for being used in a telephone exchange centre. The utility model mainly solves the problem of overload protection and automatic recovery for a communication line. The utility model comprises a push-pull linkage mechanism composed by a discharge tube, a shape memory alloy spring, a movable sliding block and an auxiliary spring, an alarm signal earthing strip, an incoming line short circuit strip, etc. The movable sliding block moves up and down by means of the characteristics of temperature distortion and memory recovery of shape memory alloy; the movable sliding block is respectively contacted with the alarm signal earthing strip and the incoming line short circuit strip to realize incoming line and an earth short circuit and raise the alarm. Then, the normal operating condition is automatically recovered. The utility model has the advantages of compact conformation, convenient use, etc.

Description

Telephone switching center with marmem from the renaturation Security Unit

The utility model belongs to the modern communication apparatus field, is specially adapted to telephone switching center.

Interference and destruction in telephone call office or telecommunications switching center in order to prevent to be struck by lightning or to cause because of factors such as power lines; Security Unit need be set in main frame; when occurring abnormal conditions such as overvoltage or overcurrent in the incoming line, produce the protection action, thereby avoid destruction internal unit.

The overvoltage protection of Security Unit mostly adopts discharge tube overvoltage heat discharge effect to cause the low-melting-point metal fusing at present, produces displacement action, thereby circuit state is changed, and reaches the purpose of protection.The characteristics of this Security Unit are that it is a kind of destructive working method, and under this working method, action is once protected in every appearance, and Security Unit also lost efficacy thereupon, must go into just can reenter normal operating conditions after whole unit is changed in the building site.

The purpose of this utility model is to provide a kind of can produce overload protection, again can be from the permanent security work unit of horizontal reset, a kind of device of update is provided for intelligent telephone exchange or telecommunications switching center.

The purpose of this utility model is to realize like this;

Telephone switching center with marmem from the renaturation Security Unit, it includes shell, base, be fixed with input terminal on the base, outlet terminal, earth terminal and alarm signal line terminals, discharge tube, current limiting tube, separation sleeve and the alarm signal indicator light that is loaded on cover top portion, it also comprises by shape memory alloy spring, the push-pull type link gear that moving slider and secondary spring and discharge tube are formed, and alarm signal ground strip, the inlet wire short-circuit piece, fixing top board, fixed base plate, earth terminal directly is communicated with fixing top board, and communicate with moving slider by secondary spring, moving slider becomes a movably earth point; Input terminal links to each other with fixed base plate, fixed base plate is communicated with the discharge tube that is fixed thereon, fixed base plate is connected with current limiting tube one end, shape memory alloy spring is positioned on the discharge tube and is attached thereto, and separation sleeve holds discharge tube and shape memory alloy spring wherein, works to isolate electricity and heat, moving slider is positioned at outer casing inner wall, moving slider is reverse U shape, is hollow in the middle of the side sidewall, and its top is clamped by secondary spring and shape memory alloy spring respectively up and down and is communicated with it; During normal operating conditions, the alarm signal ground strip is positioned at the moving slider top, the inlet wire short-circuit piece is positioned at the centre of moving slider hollow sidewall, do not contact with moving slider, alarm signal ground strip one end links to each other with the alarm signal indicator light by lead, the inlet wire of alarm signal indicator light links to each other with alarm signal terminal in the base, can form the loop by moving slider; The inlet wire short-circuit piece links to each other with input terminal in the base, can make input terminal ground connection by moving slider.

Shape memory alloy spring adopts NiTi base or Cu base shape memory alloy wire material to make.

Below in conjunction with drawings and Examples the utility model is further described:

Fig. 1 is a structural representation of the present utility model.

Fig. 2 is the structural representation of the utility model guard mode.

Fig. 3 is out of shape a time graph for the utility model shape memory alloy spring.

As shown in the figure, it is by base 10, discharge tube 8, shape memory alloy spring 6, moving slider 17, secondary spring 5, fixedly top board 1, fixed base plate 9 and indicator light 2 are formed.Base 10 is fixed with input terminal 11 and outlet terminal 14, earth terminal 12, and earth terminal 12 directly is connected with fixing top board 1, and communicates with moving slider 17 by secondary spring 5, that is to say that slide block 17 is actually a movably earth point.In addition, also have a columned separation sleeve 16 on base, it holds discharge tube 8 and shape memory alloy spring 6 wherein, works to isolate electricity and heat.Also comprise inlet wire short-circuit line 7 and signal ground sheet 18 in the device, under guard mode, connect with slide block 17.Except that binding post and indicator light, all members all are closed in the shell 4, and it also has spacing and guide effect to moving slider 17 except playing structure insulation blocking effect.

In Fig. 1, shape memory alloy spring 6, moving slider 17 and secondary spring 5 are formed a kind of push-pull type link gear.Under normal condition; the position of each assembly of Security Unit as shown in Figure 1; discharge tube 8 is open-circuit condition; shape memory alloy spring 6 is contraction state at normal temperatures; moving slider 17 is in low level; do not connect with inlet wire short-circuit piece 7 and signal ground sheet 18; the inlet wire signal passes through current limiting tube 15 to output 14; when if overcurrent appears in end of incoming cables 11, cause electric current to descend because heating can make current limiting tube 15 internal resistances increase rapidly, thereby play a protective role; when high pressure appears in end of incoming cables 11; discharge tube 8 discharge heatings make and 6 elongations of its shape memory alloy spring that closely contacts, and force secondary spring 5 to shrink, and make the moving slider 17 that is clipped in therebetween rise; if discharge effect is enough strong; duration long enough, vertical motion meeting make slide block contact with inlet wire short-circuit piece 7 and signal ground sheet 18, so just make the high pressure and the ground short circuit of inlet wire; can not enter switching system; and make discharge tube 8 quit work, and send alarm signal simultaneously, light indicator light 2.Security Unit enters guard mode, as shown in Figure 2.

After discharge tube 8 quit work, because heat radiation, the ambient temperature of shape memory alloy spring 6 can descend gradually, caused shape memory alloy spring 6 to shrink and shortened, and whole unit can come back to normal operating conditions shown in Figure 1.

Fig. 3 is under the overload operating current of 2.5A, and actual measurement the utility model shape memory alloy spring is out of shape a time graph.Shape memory alloy spring 6 elongations one time graph when the initial ascent stage of curve is energising, descending branch is contraction one time graph of natural cooling process after cutting off the power supply.Curve shows: when the displacement of moving slider 17 is designed to 3mm, and about 10 seconds of duration of short circuit, this can satisfy the requirement of related standards fully.

Shape memory alloy spring 6 in the Security Unit can select for use the NiTi base and the Cu base shape memory alloy wire material of multiple components to make after suitable moulding and heat treatment.After they and the combination of suitable annex, just determined the overall performance (startup and recovery temperature, control precision, sensitivity etc.) of entire mechanism.

In the actual Security Unit design, consider that the phone inlet wire always becomes two turnover, so every Security Unit all comprises two groups of identical said modules, constitutes a complete unit.

Claims

1, telephone switching center with marmem from the renaturation Security Unit, it includes shell (4), base (10), be fixed with input terminal (11) on the base (10), outlet terminal (14), earth terminal (12) and alarm signal line terminals (13), discharge tube (8), separation sleeve (16), be loaded on the alarm signal indicator light (2) at shell (4) top, the current limiting tube (15) that is connected with outlet terminal (14), it is characterized in that: it also comprises by shape memory alloy spring (6), moving slider (17) and secondary spring (5) are formed the push-pull type link gear with discharge tube (8), and alarm signal ground strip (18), inlet wire short-circuit piece (7), fixing top board (1), fixed base plate (9), earth terminal (12) directly is communicated with fixing top board (1), and communicate with moving slider (17) by secondary spring (5), moving slider (17) becomes a movably earth point; Input terminal (11) links to each other with fixed base plate (9), fixed base plate (9) is communicated with current limiting tube (15) one ends, fixed base plate (9) is communicated with the discharge tube that is fixed thereon (8), shape memory alloy spring (6) is positioned at discharge tube (8) and goes up and be attached thereto, separation sleeve (16) holds discharge tube (8) and shape memory alloy spring (6) wherein, moving slider (17) is positioned at shell (4) inwall, moving slider (17) is inverted U, in the middle of the one side sidewall is hollow, and its top is respectively secondary spring (5) up and down and shape memory alloy spring (6) clamps and connection with it; During normal operating conditions, alarm signal ground strip (18) is positioned at moving slider (17) top, and inlet wire short-circuit piece (7) is positioned at the centre of moving slider (17) hollow sidewall, does not contact with moving slider (17); Alarm signal ground strip (18) one ends link to each other with alarm signal indicator light (2) by lead, and the inlet wire (3) of alarm signal indicator light (2) links to each other with alarm signal line terminals (13) in the base (10), can form the loop by moving slider (17); Inlet wire short circuit (7) links to each other with input terminal (11) in the base (10), can make input terminal (11) ground connection by moving slider (17).

2, Security Unit as claimed in claim 1 is characterized in that, described shape memory alloy spring (6) adopts NiTi base or Cu base shape memory alloy wire material to make.