Utility model content
The utility model provides a kind of wide range sulfur hexafluoride gas density relay, little for the range indication range solving the sulfur hexafluoride gas density relay of prior art, is difficult to the problem realizing the display of gamut scope.
The wide range sulfur hexafluoride gas density relay that the utility model provides, comprising: the signaling gear linked together and indicating value indication mechanism;
Be provided with in described signaling gear and detect the bellows of gas density and the sensitive switch as contact in sulfur hexafluoride electrical equipment;
Described indicating value indication mechanism comprises: display Baden pipe, displays temperature compensating element, display end seat, movement, dial, pointer and display base; Described display end seat is all fixed in one end of described display Baden pipe and one end of described displays temperature compensating element, the other end of described display Baden pipe is connected on described display base, the other end of described displays temperature compensating element, is successively by display linking arm and display connecting rod is connected with described movement or the other end of described displays temperature compensating element, is directly connected with described movement, and described pointer to be installed on described movement and before being located at described dial.
Further, described displays temperature compensating element, comprises: the compensating device that bimetal leaf is formed or be filled with and compensate the compensating device of gas.
Further, described signaling gear also comprises: seal chamber, Signal Regulation mechanism and outlet Connection Block;
Described bellows is located in described seal chamber; Described Signal Regulation mechanism is corresponding with described sensitive switch to be arranged, and the holding wire of described sensitive switch is connected to described outlet Connection Block;
Wherein, second end of the first end sealing of described bellows, described bellows is connected with sulfur hexafluoride electrical equipment and described annular seal space is filled with compensation gas, or the first end of described bellows all seals with the second end, described seal chamber is connected with sulfur hexafluoride electrical equipment and is filled with compensation gas in described bellows.
Further, described signaling gear also comprises: spring and spring fixed seat;
One end of described spring is connected to the position that described Signal Regulation mechanism is connected with described bellows, and the other end of described spring is connected to described spring fixed seat; Described spring fixed seat is fixedly installed between described bellows and described sensitive switch.
Further, one end that described Signal Regulation mechanism is connected with described bellows extends to the inside of described bellows.
Further, the other end of described spring is connected to described spring fixed seat by spring adjustment mechanism.
Further, described Signal Regulation mechanism is provided with adjustment screw.
Further, described outlet Connection Block is installed transition piece by junction block and is fixedly installed on described seal chamber, or described outlet Connection Block is directly fixedly installed on described seal chamber.
Further, described seal chamber outer wrap has heat-insulation layer.
Further, wide range sulfur hexafluoride gas density relay of the present utility model also comprises: the housing being located at described seal chamber outside, is provided with anti-vibration pad between described seal chamber and described housing.
The wide range sulfur hexafluoride gas density relay that the utility model provides, the load cell of indicating value indication mechanism (display section) adopts Baden's pipe, the load cell being different from display section in prior art adopts bellows, overcome bellows displacement little, be difficult to realize gamut display problem, gamut scope (-0.1 ~ 0.9MPa) display of gas density relay can be realized easily, particularly be very easy to the display realizing being initiated with-0.1MPa, just can show vacuum degree when vacuumizing, be very easy to apply.And the load cell that its signaling gear (signal control portion) adopts is bellows simultaneously, ensure the high resistance to shock of density monitor, and the contact adopted is sensitive switch, ensures the reliable electric property of density monitor.
Embodiment:
For making the object of the utility model embodiment, technical scheme and advantage clearly, below in conjunction with the accompanying drawing in the utility model embodiment, technical scheme in the utility model embodiment is clearly and completely described, obviously, described embodiment is the utility model part embodiment, instead of whole embodiments.Based on the embodiment in the utility model, those of ordinary skill in the art are not making the every other embodiment obtained under creative work prerequisite, all belong to the scope of the utility model protection.
Fig. 1 is the partial cutaway schematic of the wide range sulfur hexafluoride gas density relay of the utility model embodiment one, as shown in Figure 1, the wide range sulfur hexafluoride gas density relay of the utility model embodiment one comprises: the signaling gear linked together and indicating value indication mechanism.Be provided with in described signaling gear and detect the bellows of gas density and the some sensitive switches as contact in sulfur hexafluoride electrical equipment.
Described indicating value indication mechanism comprises: display Baden pipe 71, displays temperature compensating element, 72, display end seat 73, movement 74, dial 75, pointer 76 and display base 77; Described display end seat 73 is all fixed in one end of described display Baden pipe 71 and one end of described displays temperature compensating element, 72, the other end of described display Baden pipe 71 is connected on described display base 77, the other end of described displays temperature compensating element, 72 passes through display linking arm successively and display connecting rod is connected with described movement 74 or the other end of described displays temperature compensating element, 72 is directly connected with described movement 74, described pointer 76 to be installed on described movement 74 and before being located at described dial 75, to realize sulfur hexafluoride density indicating value Presentation Function.Wherein, display base 77 is connected with sulfur hexafluoride electrical equipment, the mechanical deformation such as Baden's pipe 71 is rotated based on the pressure of the sulfur hexafluoride gas in sulfur hexafluoride electrical equipment, drives movement work by this mechanical deformation.The wide range sulfur hexafluoride gas density relay of the utility model embodiment one adopts display Baden pipe to substitute the critical component of bellows of the prior art as indicating value indication mechanism, gamut scope (-0.1 ~ 0.9MPa) display can be realized easily, particularly be very easy to the display realizing being initiated with-0.1MPa, just can show vacuum degree when vacuumizing, be very easy to apply.And the load cell that its signaling gear (signal control portion) adopts is bellows simultaneously, ensure the high resistance to shock of density monitor, and the contact adopted is sensitive switch, ensures the reliable electric property of density monitor.The compensating device that described displays temperature compensating element, 72 can adopt bimetal leaf to form or employing are filled with the compensating device compensating gas.
Described signaling gear specifically comprises: seal chamber 2, bellows 1, several sensitive switches 3, Signal Regulation mechanism 4 and outlet Connection Block 5.Described bellows 1 is located in described seal chamber 2; Described Signal Regulation mechanism 4 is corresponding with described sensitive switch 3 to be arranged, and the holding wire of described sensitive switch 3 is connected to described outlet Connection Block 5.The first end of described bellows 1 connects described Signal Regulation mechanism 4.
Wherein, the first end sealing of described bellows 1, the second end of described bellows 1 are connected with sulfur hexafluoride electrical equipment and are filled with compensation gas in described seal chamber 2.In addition, the first end that also can be set to described bellows all seals with the second end, described seal chamber is connected with sulfur hexafluoride electrical equipment and is filled with compensation gas in described bellows.Described sensitive switch 3 and described Signal Regulation mechanism 4 can be located in described seal chamber 2, or it is outside that described sensitive switch 3 and described Signal Regulation mechanism 4 also can be located at described seal chamber 2.Described Signal Regulation mechanism 4 can also be provided with adjustment screw 41, and adjustment screw 41 is in order to the warning of regulating density relay, locking contact operating value.Seal between described outlet Connection Block 5 and described seal chamber 2 and arrange.Described outlet Connection Block 5 can be installed transition piece by junction block and be fixedly installed on described seal chamber 2, or described outlet Connection Block 5 also can directly be fixedly installed on described seal chamber 2.The holding wire of described sensitive switch 3 can also be connected with the signal is far passed circuit, to realize the on-line monitoring of sulfur hexafluoride density.Seal chamber 2 can be made up of metal material (being such as welded), and outlet Connection Block 5 is made up of metal, glass and some lead-out wires.
The operation principle of the wide range sulfur hexafluoride gas density relay of the utility model embodiment one is: after regulating adjustment screw 41, sealing seal chamber 2, general by welding realization, then process is vacuumized to seal chamber 2, in seal chamber 2, be then filled with the compensation gas of relevant pressure according to the parameter of wide range sulfur hexafluoride gas density relay.If SF6 (sulphur hexafluoride) electric equipment does not leak gas, wide range sulfur hexafluoride gas density relay does not just send warning block signal; If SF6 electric equipment has leaked gas, when the SF6 gas density in SF6 electric equipment is near or below the density of the compensation gas in seal chamber 2, wide range sulfur hexafluoride gas density relay has just sent warning block signal, guarantees power grid security.
Fig. 2 is the partial cutaway schematic of the wide range sulfur hexafluoride gas density relay of the utility model embodiment two, as shown in Figure 2, the wide range sulfur hexafluoride gas density relay of the utility model embodiment two comprises: seal chamber 2, bellows 1, several sensitive switches 3, Signal Regulation mechanism 4, spring 61, spring fixed seat 62 and outlet Connection Block 5.Be filled with compensation gas in described seal chamber 2, described bellows 1, described sensitive switch 3 and described Signal Regulation mechanism 4 are located in described seal chamber 2; Described Signal Regulation mechanism 4 is corresponding with described sensitive switch 3 to be arranged, and the holding wire of described sensitive switch 3 is drawn by described outlet Connection Block 5, seals and arrange between described outlet Connection Block 5 and described seal chamber 2; One end (first end) of described bellows 1 is sealing and connects described Signal Regulation mechanism 4, the other end (the second end) of described bellows 1 is connected with sulfur hexafluoride electrical equipment by jointing 91, is filled with compensation gas in described seal chamber 2.One end of described spring 61 is connected to the position that described Signal Regulation mechanism 4 is connected with described bellows 1, and the other end of described spring 61 is fixedly connected on described spring fixed seat 62 by spring adjustment mechanism 63; Described spring fixed seat 62 is fixedly installed between described bellows 1 and described sensitive switch 3.Described Signal Regulation mechanism 4 can also be provided with adjustment screw 41, and adjustment screw 41 is in order to the warning of regulating density relay, locking contact operating value.The all right connection signal teletransmission circuit of holding wire of described sensitive switch 3, to realize the on-line monitoring of sulfur hexafluoride density.
The wide range sulfur hexafluoride gas density relay of the utility model embodiment two can also comprise: housing 81, the heat-insulation layer 82 being wrapped in seal chamber 2 outside, outlet Ge Lan 92, keeper (or guide) 93 and junction block 94.Heat-insulation layer 82 insulation effects, can avoid ambient temperature to change suddenly caused false alarm effectively.
The operation principle of the wide range sulfur hexafluoride gas density relay of the utility model embodiment two is: bellows 1 is mainly as gas pressure transfer device, realize spring 61 by adopting the combination of bellows 1 and spring 61 and be used as the main measuring component of pressure, improve measuring accuracy further.If SF6 electric equipment does not leak gas, wide range sulfur hexafluoride gas density relay does not just send warning block signal; If SF6 electric equipment has leaked gas, when the SF6 gas density in SF6 electric equipment is near or below the density of the compensation gas in seal chamber 2, wide range sulfur hexafluoride gas density relay has just sent warning block signal, guarantees power grid security.
The wide range sulfur hexafluoride gas density relay of the utility model embodiment two also comprises: the indicating value indication mechanism that the independence being located at described seal chamber sidewall is arranged.Described indicating value indication mechanism comprises: display Baden pipe 71, displays temperature compensating element, 72, display end seat 73, movement 74, dial 75, pointer 76 and display base 77.Display base 77 is connected with sulfur hexafluoride electrical equipment.Described display end seat 73 is all fixed in one end of described display Baden pipe 71 and one end of described displays temperature compensating element, 72, the other end of described display Baden pipe 71 is connected on described display base 77, the other end of described displays temperature compensating element, 72 is connected with described movement 74 by display connecting rod or the other end of described displays temperature compensating element, 72 is directly connected with described movement 74, described pointer 76 to be installed on described movement 74 and before being located at described dial 75, to realize density indicating value Presentation Function.The wide range sulfur hexafluoride gas density relay of the utility model embodiment two can realize gamut scope (-0.1 ~ 0.9MPa) display easily, particularly be very easy to the display realizing being initiated with-0.1MPa, just can show vacuum degree when vacuumizing, be very easy to apply.
Fig. 3 is the partial cutaway schematic of the wide range sulfur hexafluoride gas density relay of the utility model embodiment three, as shown in Figure 3, the wide range sulfur hexafluoride gas density relay of the utility model embodiment three comprises: seal chamber 2, bellows 1, several sensitive switches 3, Signal Regulation mechanism 4, spring 61, spring fixed seat 62 and outlet Connection Block 5.First end and second end of described bellows 1 all seal, particularly, the first end of bellows 1 is sealing and connection signal governor motion 4 and spring 33, second end sealing of bellows 1 (such as, seal welding) at the inwall of seal chamber 2, described seal chamber 2 is connected with sulfur hexafluoride electrical equipment by jointing 91, is filled with compensation gas in described bellows 1.
One end that described Signal Regulation mechanism 4 is connected with described bellows 1 extends to the inside of described bellows 1.One end of described spring 61 is connected to the position that described Signal Regulation mechanism 4 is connected with described bellows 1, and the other end of described spring 61 is fixedly connected on described spring fixed seat 62 by spring adjustment mechanism 63; Described spring fixed seat 62 is fixedly installed between described bellows 1 and described sensitive switch 3.
The wide range sulfur hexafluoride gas density relay of the utility model embodiment three can also comprise: the indicating value indication mechanism of housing 81, the heat-insulation layer 82 being wrapped in seal chamber 2 outside, outlet Ge Lan 92, keeper (or guide) 93, junction block 94 and relatively independent setting.Described indicating value indication mechanism comprises: display Baden pipe 71, displays temperature compensating element, 72, display end seat 73, movement 74, dial 75, pointer 76 and display base 77.Display base 77 is connected with sulfur hexafluoride electrical equipment.Described display end seat 73 is all fixed in one end of described display Baden pipe 71 and one end of described displays temperature compensating element, 72, the other end of described display Baden pipe 71 is connected on described display base 77, the other end of described displays temperature compensating element, 72 passes through display linking arm successively and display connecting rod is connected with described movement 74 or the other end of described displays temperature compensating element, 72 is directly connected with described movement 74, described pointer 76 to be installed on described movement 74 and before being located at described dial 75, to realize density indicating value Presentation Function.
The operation principle of the wide range sulfur hexafluoride gas density relay of the utility model embodiment three is: bellows 1 is mainly as gas pressure transfer device, realize spring 61 by adopting the combination of bellows 1 and spring 61 and be used as the main measuring component of pressure, improve measuring accuracy further.If SF6 electric equipment does not leak gas, wide range sulfur hexafluoride gas density relay does not just send warning block signal; If SF6 electric equipment has leaked gas, when the SF6 gas density in SF6 electric equipment is near or below the density of the compensation gas in seal chamber 2, two ends in seal chamber 2 are all subject to the pressure effect of SF6 gas in SF6 electric equipment by the both sides of the bellows 1 sealed, wide range sulfur hexafluoride gas density relay just sends warning block signal, guarantees power grid security.
Fig. 4 is the partial cutaway schematic of the wide range sulfur hexafluoride gas density relay of the utility model embodiment four, as shown in Figure 4, the wide range sulfur hexafluoride gas density relay of the utility model embodiment four comprises: seal chamber 2, bellows 1, several sensitive switches 3, Signal Regulation mechanism 4 and outlet Connection Block 5.The first end of described bellows 1 and the second end all seal and the inside of bellows 1 is filled with compensation gas, and described seal chamber 2 is connected with sulfur hexafluoride electrical equipment by jointing 91.The wide range sulfur hexafluoride gas density relay of the utility model embodiment four also comprises: housing 81, the heat-insulation layer 82 being wrapped in seal chamber 2 outside, outlet Ge Lan 92, keeper (or guide) 93, junction block 94 and the independent indicating value indication mechanism arranged.Described indicating value indication mechanism comprises: display Baden pipe 71, displays temperature compensating element, 72, display end seat 73, movement 74, dial 75, pointer 76 and display base 77.Display base 77 is connected with sulfur hexafluoride electrical equipment.Described display end seat 73 is all fixed in one end of described display Baden pipe 71 and one end of described displays temperature compensating element, 72, the other end of described display Baden pipe 71 is connected on described display base 77, the other end of described displays temperature compensating element, 72 passes through display linking arm successively and display connecting rod is connected with described movement 74 or the other end of described displays temperature compensating element, 72 is directly connected with described movement 74, described pointer 76 to be installed on described movement 74 and before being located at described dial 75, to realize density indicating value Presentation Function.Its operation principle is as follows: if SF6 electric equipment does not leak gas, and density monitor does not just send warning block signal; And if SF6 electric equipment has leaked gas, when the SF6 gas density in SF6 electric equipment is near or below the density of the compensation gas in bellows 1, density monitor has just sent warning block signal, guarantees power grid security.The outside of seal chamber 2 is wrapped with heat preservation member 82, plays insulation effect, can effectively avoid ambient temperature to change suddenly caused false alarm.
Fig. 5 is the partial cutaway schematic of the wide range sulfur hexafluoride gas density relay of the utility model embodiment five, as shown in Figure 5, the wide range sulfur hexafluoride gas density relay of the utility model embodiment five comprises: seal chamber 2, bellows 1, several sensitive switches 3, Signal Regulation mechanism 4 and outlet Connection Block 5, the housing 81 being located at seal chamber 2 outside, the heat-insulation layer 82 being wrapped in seal chamber 2 outside, outlet Ge Lan 92, keeper (or guide) 93, junction block 94 and the independent indicating value indication mechanism arranged.Housing 81 adopts general conventional densities relay or manometric housing.Described indicating value indication mechanism comprises: display Baden pipe 71, displays temperature compensating element, 72, display end seat 73, movement 74, dial 75, pointer 76 and display base 77.Display base 77 is connected with sulfur hexafluoride electrical equipment.Described display end seat 73 is all fixed in one end of described display Baden pipe 71 and one end of described displays temperature compensating element, 72, the other end of described display Baden pipe 71 is connected on described display base 77, the other end of described displays temperature compensating element, 72 passes through display linking arm successively and display connecting rod is connected with described movement 74 or the other end of described displays temperature compensating element, 72 is directly connected with described movement 74, described pointer 76 to be installed on described movement 74 and before being located at described dial 75, to realize density indicating value Presentation Function.
Fig. 6 is the partial cutaway schematic of the wide range sulfur hexafluoride gas density relay of the utility model embodiment six, as shown in Figure 6, the wide range sulfur hexafluoride gas density relay of the utility model embodiment six comprises: seal chamber 2, bellows 1, several sensitive switches 3, Signal Regulation mechanism 4, outlet Connection Block 5, the housing 81 being located at seal chamber 2 outside, the heat-insulation layer 82 being wrapped in seal chamber 2 outside, outlet Ge Lan 92, keeper (or guide) 93, junction block 94 and the independent indicating value indication mechanism arranged.Housing 81 adopts general conventional densities relay or manometric housing as its shell, and jointing 91 is radial manner, jointing 91 is communicated with the second end of bellows 1 by connecting tracheae 95, the first end sealing of bellows 1, jointing 91 is communicated with sulfur hexafluoride electrical equipment, is filled with compensation gas in seal chamber 2.Described indicating value indication mechanism comprises: display Baden pipe 71, displays temperature compensating element, 72, display end seat 73, movement 74, dial 75, pointer 76 and display base 77.Display base 77 is connected with sulfur hexafluoride electrical equipment.Described display end seat 73 is all fixed in one end of described display Baden pipe 71 and one end of described displays temperature compensating element, 72, the other end of described display Baden pipe 71 is connected on described display base 77, the other end of described displays temperature compensating element, 72 passes through display linking arm successively and display connecting rod is connected with described movement 74 or the other end of described displays temperature compensating element, 72 is directly connected with described movement 74, described pointer 76 to be installed on described movement 74 and before being located at described dial 75, to realize density indicating value Presentation Function.
Fig. 7 is the partial cutaway schematic of the wide range sulfur hexafluoride gas density relay of the utility model embodiment seven, as shown in Figure 7, the wide range sulfur hexafluoride gas density relay of the utility model embodiment seven comprises: seal chamber 2, bellows 1, several sensitive switches 3, Signal Regulation mechanism 4, outlet Connection Block 5, be located at described seal chamber 2 outside housing 81, be located at anti-vibration pad 96 between described seal chamber 2 and described housing 81 and indicating value indication mechanism, anti-vibration pad 96 can improve shock resistance further.Housing 81 adopts general conventional densities relay or manometric housing as its shell, jointing 91 is radial manner, jointing 91 is communicated with the second end of bellows 1 by connecting tracheae 95, the first end sealing of bellows 1, jointing 91 is communicated with sulfur hexafluoride electrical equipment, is filled with compensation gas in seal chamber 2.Indicating value indication mechanism comprises: display Baden pipe 71, displays temperature compensating element, 72, display end seat 73, movement 74, dial 75, pointer 76 and display base 77.Display base 77 is connected with sulfur hexafluoride electrical equipment.Described display end seat 73 is all fixed in one end of described display Baden pipe 71 and one end of described displays temperature compensating element, 72, the other end of described display Baden pipe 71 is connected on described display base 77, the other end of described displays temperature compensating element, 72 passes through display linking arm successively and display connecting rod is connected with described movement 74 or the other end of described displays temperature compensating element, 72 is directly connected with described movement 74, described pointer 76 to be installed on described movement 74 and before being located at described dial 75, to realize density indicating value Presentation Function.
The wide range sulfur hexafluoride gas density relay of the utility model embodiment eight comprises: seal chamber, two bellowss, several sensitive switches, Signal Regulation mechanism, outlet Connection Block and indicating value indication mechanisms.Two bellowss are respectively the first bellows and the second bellows.Second bellows is located in seal chamber, and sensitive switch and Signal Regulation mechanism are located at outside seal chamber; Signal Regulation mechanism is corresponding with sensitive switch to be arranged, and the holding wire of sensitive switch is connected to outlet Connection Block; Second end of the first bellows is tightly connected the first end of the second bellows, and Signal Regulation mechanism is connected to the junction of the first bellows and the second bellows.Wherein, second end of the first end sealing of described second bellows, described second bellows is connected with sulfur hexafluoride electrical equipment and described annular seal space is filled with compensation gas, or the first end of described second bellows all seals with the second end, described seal chamber is connected with sulfur hexafluoride electrical equipment and is filled with compensation gas in described bellows.Indicating value indication mechanism comprises: display Baden pipe, displays temperature compensating element, display end seat, movement, dial, pointer and display base.Described display end seat is all fixed in one end of described display Baden pipe and one end of described displays temperature compensating element, the other end of described display Baden pipe is connected on described display base, the other end of described displays temperature compensating element, passes through display linking arm successively and display connecting rod is connected with described movement or the other end of described displays temperature compensating element, is directly connected with described movement, described pointer to be installed on described movement and before being located at described dial, realize density indicating value Presentation Function, so, the density monitor (-0.1 ~ 0.9MPa) of gamut scope can be realized easily.
Fig. 8 is the partial cutaway schematic of the high antivibration sulfur hexafluoride gas density relay of the utility model embodiment nine, as shown in Figure 8, the high antivibration sulfur hexafluoride gas density relay of the utility model embodiment nine comprises: seal chamber 2, bellows 1, several sensitive switches 3, Signal Regulation mechanism 4, outlet Connection Block 5, the housing 81 being located at described seal chamber 2 outside, spring 61, spring fixed seat 62 and indicating value indication mechanism.Indicating value indication mechanism comprises: display Baden pipe 71, temperature compensating element 72, display end seat 73, movement 74, dial 75, pointer 76 and pedestal 77.One end (first end) of described bellows 1 is sealing and connects described Signal Regulation mechanism 4, and the other end (the second end) of described bellows 1 is connected with sulfur hexafluoride electrical equipment by jointing 91.One end that described Signal Regulation mechanism 4 is connected with described bellows 1 extends to the inside of described bellows 1.One end of described spring 61 is connected to the position that described Signal Regulation mechanism 4 is connected with described bellows 1, and the other end of described spring 61 is fixedly connected on described spring fixed seat 62 by spring adjustment mechanism 63; Described spring fixed seat 62 is fixedly installed between described bellows 1 and described sensitive switch 3.
Wide range sulfur hexafluoride gas density relay of the present utility model, signaling gear adopts bellows, ensures that anti-seismic performance is good; Indicating value indication mechanism adopts Baden's pipe, realize owing to adopting Baden's pipe, overcome bellows displacement little, be difficult to realize gamut display problem, the density monitor (-0.1 ~ 0.9MPa) of gamut scope can be realized easily, particularly be very easy to the display realizing being initiated with-0.1MPa, just can show vacuum degree when vacuumizing, be very easy to apply.Additionally use displays temperature compensating element, in addition to realize the temperature compensation function of indicating value display section, improve and ensure that precision.In a word, wide range sulfur hexafluoride gas density relay of the present utility model have without oil, resistance to shock again good, precision is high, the advantage of good electric property, long working life, gamut indication range.Simultaneously because described sensitive switch can be located in described seal chamber, and in seal chamber, have sulfur hexafluoride gas, because sulfur hexafluoride gas has very strong insulation and arc extinguishing ability, so the electric terminal of the utility model Technology Density relay has extraordinary electric property, use reliable, contacts is reliable, and the life-span is long, and this is also very large innovative point of the present utility model and feature.
Last it is noted that above each embodiment is only in order to illustrate the technical solution of the utility model, be not intended to limit; Although be described in detail the utility model with reference to foregoing embodiments, those of ordinary skill in the art is to be understood that: it still can be modified to the technical scheme described in foregoing embodiments, or carries out equivalent replacement to wherein some or all of technical characteristic; And these amendments or replacement, do not make the essence of appropriate technical solution depart from the scope of each embodiment technical scheme of the utility model.