HK1112866A - An unrecoverable line-type temperature sensitive detector having short-circuit fault alarm function - Google Patents

Description

Unrecoverable linear temperature-sensitive detector with short-circuit fault alarm

Technical Field

The invention relates to an unrecoverable linear temperature-sensing detector, in particular to an unrecoverable linear temperature-sensing detector with a short-circuit fault alarm function.

Background

The traditional unrecoverable linear temperature-sensing detector is a fire detector with wide application. Fig. 1 and 2 are sectional views illustrating a detection cable and a detection cable of a conventional non-recoverable linear temperature-sensitive detector. In the detection cable of the detector, there is a sheath 1, there are two (or more than two, such as three, four, etc.) detection conductors 3 twisted together in the sheath, the detection conductor can be the elastic conductor, such as memory alloy silk, etc., the detection conductor is coated with the plastic layer 2 with certain melting point or melting point, when the detection cable is heated, after the temperature reaches certain degree, the plastic layer softens or melts, under the elastic force of elastic conductor (or memory alloy silk), contact each other between the conductors, namely the short circuit takes place, thus achieve the goal of fire alarm. The advantages of such a detector are: when the temperature of any point on the detection cable reaches the set alarm temperature, the detection cable can alarm in a short circuit mode, the alarm sensitivity of the detector is irrelevant to the heated length, and therefore the detection sensitivity of the detector to the fire caused by local overheating of a protected object or an external fire source is high; meanwhile, when one of the detection conductors of the detector is broken, fault alarm can be carried out. The temperature-sensing detector has no short-circuit fault alarm function, only has a fire alarm function under the condition of short circuit, and can not distinguish short-circuit fault from short-circuit fire alarm signal. Therefore, there is a need for an unrecoverable linear temperature-sensitive detector with short-circuit fault alarm that can distinguish short-circuit faults from fire short-circuits.

Disclosure of Invention

The invention aims to provide an unrecoverable linear temperature-sensitive detector with a short-circuit fault alarm, which can distinguish a short-circuit fault from a short-circuit fire alarm, thereby being capable of respectively carrying out the short-circuit fault alarm and the fire alarm under different conditions, solving the defect that the unrecoverable linear temperature-sensitive detector in the prior art does not have the short-circuit fault alarm, and improving the reliability of the unrecoverable linear temperature-sensitive detector.

The purpose of the invention is realized by the following technical scheme: the utility model provides a take short-circuit fault alarm's unrecoverable formula line type temperature-sensing detector, line type temperature-sensing detector is including surveying the cable, resistance, and resistance signal measuring device, survey the cable and include two piece at least parallel arrangement's detection conductor and fusible insulating layer, its characterized in that: the detection cable further comprises a semiconductor layer, wherein the semiconductor layer and the fusible insulating layer are arranged between the detection conductors to separate the detection conductors.

In the invention, the detection cable of the unrecoverable linear temperature-sensitive detector further comprises a conductive layer which is arranged between the semiconductor material layer and the meltable insulation layer and is parallel to the semiconductor material layer and the meltable insulation layer. The conductive layer is an intermittent conductive layer or a continuous conductive layer providing intermittent conduction or continuous conduction. The conductive layer can be made of metal wires, non-metal wires, metal sheets, metal foil strips, hollow cylindrical metal sleeves, conductive adhesive or conductive paint.

The unrecoverable linear temperature-sensing detector further comprises a sheath which is coated outside the detection cable.

In the non-recoverable linear temperature-sensing detector, at least one of the detection conductors is an elastic conductor. The elastic conductor is an elastic steel wire or a memory alloy wire. The designed value of the martensite reverse phase transformation final temperature Af of the memory alloy wire is within the range of 20-140 ℃.

In the unrecoverable line-type temperature-sensitive fire detector of the present invention, the semiconductor layer is made of at least one of PTC, CRT, NTC, conductive rubber, and conductive ceramic. The melting temperature of the meltable insulating layer is 40-180 ℃. The meltable insulation layer is made of at least one of wax, naphthalene anthracene, stearic acid, crystal rose, low-density polyethylene, high-density polyethylene, polypropylene and polyvinyl chloride.

Compared with the prior art, the detector of the invention adds a layer of semiconductor material layer between the two polar conductors of the existing unrecoverable linear temperature-sensing detector, so that the resistance values of the detection cables measured under different conditions are different, thereby distinguishing short-circuit faults from fire short circuits, eliminating the defect that the existing detector can not distinguish the two conditions of short-circuit faults and short-circuit fire alarms, solving the problem that the unrecoverable linear temperature-sensing detector in the prior art has no short-circuit fault alarm, and simultaneously, the unrecoverable linear temperature-sensing detector of the invention can also provide the functions of open circuit faults and the like, thereby leading the unrecoverable linear temperature-sensing detector of the invention to have high reliability.

Drawings

FIG. 1 is a schematic diagram of a conventional non-recoverable linear temperature-sensitive detector cable;

FIG. 2 is a schematic diagram showing a cross section of a conventional non-recoverable linear temperature-sensitive detector detection cable;

FIG. 3 is a schematic diagram illustrating a cross-section of a detection cable of the unrecoverable linear temperature-sensitive detector according to one embodiment of the present invention;

FIG. 4 is a schematic diagram illustrating a longitudinal cross-section of a detection cable of the unrecoverable linear temperature-sensitive detector according to one embodiment of the present invention;

FIG. 5 is a schematic diagram showing an equivalent circuit of the unrecoverable linear temperature-sensitive detector of the present invention; and

FIG. 6 is a cross-sectional view of a cable for detecting a non-recoverable linear temperature-sensitive detector according to another embodiment of the present invention.

Detailed Description

The temperature-sensitive detector of the present invention will be described in detail with reference to the accompanying drawings.

The unrecoverable line-type fire disaster temperature-sensing detector comprises a detection cable, a resistor, an electric signal measuring device and the like, wherein the detection cable comprises two detection conductors, a semiconductor layer and a fusible insulating layer, and the semiconductor layer and the fusible insulating layer are arranged between the two detection conductors. Fig. 3 is a schematic view showing a partial cross-section of a line type temperature sensing element of an unrecoverable line type fire temperature-sensitive detector according to the present invention, such as a detection cable, and fig. 4 is a schematic view showing a longitudinal section of the detection cable. As shown in fig. 3 and 4, in the unrecoverable line-type fire temperature-sensitive detector of the present invention, the detection cable includes two detection conductors 4, 5, a semiconductor material layer 7 and a fusible insulation layer 6 disposed between the two detection conductors. The unrecoverable line type fire temperature-sensing detector of the present invention further comprises a resistor R2, and an electrical signal measuring device 9, as shown in fig. 5. In the present invention, the two detection conductors 4 and 5 are arranged in parallel, i.e. flush-coupled. Parallel arrangements may include coaxial arrangements, arrangements parallel to each other, or intertwined with each other, etc. The semiconducting layer 7 and the fusible insulation layer 6 are arranged between the two detection conductors 4 and 5, parallel to the detection conductors 4 and 5, separating them, the fusible insulation layer preferably having a melting temperature of 40 ℃ to 180 ℃.

Fig. 5 is an equivalent circuit diagram showing a line type fire temperature-sensitive detector of the present invention. As shown in fig. 5, the unrecoverable line-type fire temperature sensing detector of the present invention comprises a resistor R2, and an electrical signal measuring device 9, wherein the detecting conductors 4 and 5 are equivalent to lead wires 10 and 11, the fusible insulation layer 6 is equivalent to a switch K in the figure, and the semiconductor material layer 7 is equivalent to a resistor R1 in the figure, wherein the resistor R2 is a terminal resistor of the line-type temperature sensing element, and preferably has a value of 1K Ω -20M Ω, a signal input end of the resistor signal measuring device 9 is electrically connected to one end of the detecting conductor, and a resistor R2 is connected to the other end of the detecting conductor, that is, the electrical signal measuring device 9 is connected to one end of the line-type temperature sensing element, and the resistor R2 is connected.

Under normal operating conditions, i.e. no fire, no fault, i.e. the fusible insulating layer is intact, and the sensing conductor is separated from the semiconductor material layer, when the switch K is not closed, the electrical signal measuring device 9 measures the linear temperature sensing element to obtain the resistance value R which is the resistance value of the resistor R2, i.e. R2.

When an open circuit fault occurs, for example, a certain position of the linear temperature sensing element is open circuit, for example, at least one of the two detection conductors of the detector is open circuit, etc., the fusible insulating layer may still be intact and still separate the detection conductors together with the semiconductor material layer, that is: corresponding to switch K in fig. 5 not being closed, but conductor 10, 11 and resistor R2 form a circuit break somewhere in the circuit. Therefore, the electrical signal measuring device measures the probe cable at this time so that the resistance value R is infinite, that is, R ∞. At this time, the electric signal measuring device 9 sends out an open-circuit fault signal to alarm the open-circuit fault.

When a short-circuit fault occurs, for example, in the case of no fire, a complete conductive contact occurs somewhere between the two detection conductors of the detection cable of the detector, that is, a short-circuit fault occurs, which is equivalent to that a short-circuit occurs somewhere in the circuit formed by the wires 10 and 11 and the resistor R2 in fig. 5, at this time, the fusible insulating layer may still be intact, and the switch K in fig. 5 is not closed, but because of the short-circuit, the result of the resistor R measured by the electrical signal measuring device on the linear temperature sensing element, that is, the detection cable, is approximately zero, that is, R ≈ 0. At this time, the electric signal measuring device 9 sends out a short-circuit fault signal to give an alarm for the short-circuit fault.

When a fire disaster occurs, namely, when the linear temperature sensing element of the detector is heated, the temperature of the linear temperature sensing element rises, when the linear temperature sensing element of the detector is heated and the temperature rises to reach the softening temperature area of the fusible insulating layer, the fusible insulating layer is melted, softened or melted, and the fusible insulating layer between the two detection conductors of the heated part of the detection cable of the detector is eliminated under the action of the elastic force of the two detection conductors. This is shown in the equivalent circuit of fig. 5, where the fusible insulation layer of the line-type temperature sensing element corresponding to the location indicated by reference numeral 8 in the figure melts and the switch K at 8 is closed. In this case, there is still a layer of semiconductor material between the two detecting conductors of the heated portion of the detector, which portion may be equivalent to the resistance R1 at 7a in fig. 5, and the value of the resistance R measured by the electrical signal measuring device is determined by the equivalent resistance R1 and the terminating resistance R2 being connected in parallel, the measured value of the resistance R being smaller than the resistance value of the terminating resistance R2, i.e. 0 < R2. The resistance signal measuring device will output fire alarm signal according to the measuring result.

The linear temperature-sensing fire detector of the embodiment can reliably send out different alarm signals according to different results measured by the electric signal measuring device, thereby greatly improving the reliability of the unrecoverable linear temperature-sensing fire detector.

In the present invention, at least one of the two detecting conductors 4 and 5 of the detecting cable may be an elastic conductor, such as an elastic steel wire or a memory alloy wire, and the other detecting conductor may be a metal wire or an elastic conductor, such as an elastic steel wire or a memory alloy wire. The memory alloy wire can be made of nickel-titanium memory alloy, nickel-titanium-copper memory alloy, iron-based memory alloy, copper-based memory alloy, other materials with memory function and the like. The design value of the martensite reverse transformation end temperature Af of the memory alloy wire is preferably in the range of 20-140 ℃.

In the present invention, the detection cable may include two or more detection conductors, the detection conductors may be disposed in parallel, such as coaxially disposed, or disposed in parallel or wound with each other, and the semiconductor layer and the fusible insulation layer are disposed between the detection conductors in parallel with the detection conductors. For example, when the detecting conductors are disposed parallel or coaxial with each other, the semiconductor material layer and the fusible insulation layer may be disposed between the detecting conductors and parallel or coaxial with the detecting conductors. When the detecting conductors are wound with each other, the semiconductor material layer and the fusible insulating layer may be coated on the detecting conductors in a conventional coating manner, and then the winding is completed. The cladding may be to clad a semiconductor material layer and then a fusible insulation layer on one of the detecting conductors, or conversely, to clad a fusible insulation layer and then a semiconductor material layer, and so on. Of course, the semiconductor material layer and the fusible insulating layer may be coated on different detecting conductors, respectively.

In the present invention, the semiconductor layer may be made of at least one material having semiconductor characteristics such as PTC, CRT, NTC, conductive rubber, conductive ceramic, etc., but may be made of other suitable materials, and the thickness of the semiconductor layer may preferably be between 0.1 and 5 mm. The meltable insulation layer may be made of at least wax, naphthalene anthracene, stearic acid, rose, low density polyethylene, high density polyethylene, polypropylene, polyvinyl chloride, etc., although other suitable materials may be used, and the thickness of the coating layer may preferably be between 0.1 and 2 mm.

Fig. 6 shows another embodiment of the unrecoverable linear temperature-sensitive detector with short-circuit fault alarm function of the present invention. As shown in fig. 6, in the present embodiment, the linear temperature sensing element of the linear temperature-sensitive detector of the present invention includes two parallel-arranged detecting conductors 13, 14, a semiconductor material layer 15, a conductive layer 16, and a fusible insulation layer 17. The probe may also include a resistor R2 (not shown) and an electrical signal measuring device (not shown). Wherein, the semiconductor layer 15 and the meltable insulation layer 17 are arranged between the two detection conductors 13 and 14, parallel to the detection conductors 13 and 14, to separate the two detection conductors, and the conductive layer 16 is arranged between the semiconductor material layer 15 and the meltable insulation layer 17, parallel to the semiconductor material layer 15 and the meltable insulation layer 17, to separate the semiconductor material layer 15 and the meltable insulation layer 17.

In this embodiment, in addition to the above-described operation, since the conductive layer 16 is provided between the semiconductor material layer 15 and the fusible insulating layer 17 in parallel, the difference between the fire alarm measurement value R of the electrical signal measuring device and the measurement value R ═ R2 in the normal operation condition can be increased, thereby providing a more accurate fire alarm.

In this embodiment, the conductive layer 16 may be discontinuous or continuous, that is, the conductive layer may be discontinuous or continuous. The conductive layer 16 is arranged in parallel with and between the layer of semiconducting material 15 and the fusible insulation layer 17 and can be arranged in several ways: a wound arrangement, a parallel arrangement, a coaxial arrangement, etc., although other known arrangements may be used.

The conductive layer can be made of metal wires, non-metal wires, metal sheets, metal foil strips, hollow cylindrical metal sleeves, conductive glue or paint and the like.

The conductive layer which is conducted intermittently can be made in advance by using a metal wire, a non-metal wire, a metal sheet, a metal foil tape, a hollow cylindrical metal sleeve and the like, or can be made into a state of intermittent conduction by using a physical or chemical method such as mechanical cutting and the like after the conductive layer which is conducted continuously is arranged. If the conductive layer is made of conductive adhesive or paint, the conductive layer can be a conductive band/layer which is intermittently coated, sprayed or immersed outside the semiconductor material layer or the fused insulating layer along the length direction, or a conductive paint or paint band/layer which is continuously conducted can be processed into an intermittently conductive state by a physical or chemical method such as mechanical cutting after being arranged. The conductive length of each section of the conductive layer which is conducted intermittently is preferably more than 0.05m, and the intermittent distance between the conductive sections, namely, the non-conductive length is preferably 0.1-10 mm.

As previously mentioned, the two detecting conductors may be disposed in parallel, such as coaxially, in parallel or in a wound arrangement, etc., and the layer of semiconducting material and the fusible insulation layer may be disposed in parallel between the detecting conductors, and similarly to the above, the conducting layer 16 may be disposed in parallel between the layer of semiconducting material and the fusible insulation layer. Under the mode that the detection conductor adopts the winding to set up, semiconductor material layer, conducting layer and can melt on the insulating layer can cladding detection conductor, also can cladding respectively on two different detection conductors, for example a detection conductor cladding semiconductor material layer and conducting layer, another cladding has the melting insulating layer, or a cladding has the semiconductor layer, another cladding has conducting layer and melting insulating layer, etc.. In the case where the detection conductors are arranged in parallel or coaxially, the semiconductor layer, the conductive layer and the meltable insulation layer are disposed between the detection conductors, similarly to the foregoing.

In the unrecoverable linear temperature-sensing detector with the short-circuit fault alarm function, a sheath can be coated outside the linear temperature-sensing fire detection cable to play the roles of protection and insulation. Such as a sheath covering the detecting conductor, the semiconductor layer and the fusible insulating layer, or the detecting conductor, the semiconductor layer, the conducting layer and the fusible insulating layer, etc.

Although the present invention has been described above with reference to the drawings and embodiments, it is to be understood that variations or modifications may be made by those skilled in the art without departing from the true spirit and scope of the present invention. For example, although the above-mentioned embodiment shows the case of including only two detecting conductors, it is well within the skill of the art to employ more than two detecting conductors as required, for example, the line-type temperature sensing element may include three detecting conductors, etc., and the semiconductor layer, the conductive layer, and the meltable insulating layer may be disposed in parallel with and between at least two detecting conductors to separate at least two detecting conductors from each other, etc.

Claims (12)

1. The utility model provides a take short-circuit fault alarm's unrecoverable formula line type temperature-sensing detector, line type temperature-sensing detector is including surveying the cable, resistance, and resistance signal measuring device, survey the cable and include two piece at least parallel arrangement's detection conductor and fusible insulating layer, its characterized in that: the detection cable further comprises a semiconductor layer, wherein the semiconductor material layer and the fusible insulating layer are arranged between the detection conductors to separate the detection conductors.

2. The linear temperature-sensitive unrecoverable detector according to claim 1, further comprising a sheath covering the detection cable.

3. The linear temperature-sensitive unrecoverable detector according to claim 1, wherein said detection cable further comprises a conductive layer disposed between said semiconductive material layer and said fusible insulation layer in parallel with said semiconductive material layer and said fusible insulation layer.

4. The linear temperature-sensitive detector of claim 3, wherein: the conductive layer is an intermittent conductive layer or a continuous conductive layer providing intermittent conduction or continuous conduction.

5. The linear temperature-sensitive unrecoverable detector according to claim 4, further comprising a sheath covering the detection cable.

6. The linear temperature-sensitive detector of claim 4, wherein: the conducting layer is at least made of metal wires, non-metal wires, metal sheets, metal foil strips, hollow cylindrical metal sleeves, conducting adhesive or conducting paint.

7. The linear temperature-sensitive unrecoverable detector according to any one of claims 1 to 6, wherein at least one of said detecting conductors is an elastic conductor.

8. The linear temperature-sensitive detector of claim 7, wherein: the elastic conductor is an elastic steel wire or a memory alloy wire.

9. The linear temperature-sensitive detector of claim 8, wherein: the designed value of the martensite reverse phase transformation final temperature Af of the memory alloy wire is within the range of 20-140 ℃.

10. The linear temperature-sensitive detector of claim 7, wherein: the semiconductor layer is made of at least one of PTC, CRT, NTC, conductive rubber, and conductive ceramic.

11. The unrecoverable line-type temperature-sensitive fire detector according to claim 7, wherein: the melting temperature of the meltable insulating layer is 40-180 ℃.

12. The unrecoverable line-type temperature-sensitive fire detector according to claim 11, wherein: the meltable insulation layer is made of at least one of wax, naphthalene anthracene, stearic acid, crystal rose, low-density polyethylene, high-density polyethylene, polypropylene and polyvinyl chloride.