Wire and cable vertical combustion test equipment

Abstract

The invention relates to the technical field of optical density testing of cable combustion, in particular to electric wire and cable vertical combustion test equipment which comprises a shading test box, a sample holder arranged in the shading test box and an igniter arranged on one side of the sample holder. The reflecting mirror is arranged in the light-shielding test box in a limited space, multiple times of reflection are performed in smoke in the light-shielding test box in the limited space to form an extended light-transmitting light path, the driving part drives the uppermost reflecting mirror to turn over and rotate at a fixed angle to form an alternately-changed light-transmitting light path, and the scraping plate can be driven to timely clean the surface of each reflecting mirror. Under the cooperation of the driving part and the transmission part, a negative pressure environment is formed in the upper area of the inner cavity of the shading test box to simulate the combustion condition of the wire cable under the actual installation condition, and the upward suction effect similar to a chimney is formed on smoke in the shading test box under the negative pressure environment; and the authenticity of the tested test data is ensured.

Description

Technical Field

[0001] The present invention relates to the technical field of optical density testing for cable combustion, and particularly to a vertical combustion test device for electric wires and cables. Background Art

[0002] In the application process of various cables such as power electric wires and cables, control cables, and communication cables, it is required that they have high fire prevention and low smoke generation capabilities during combustion. In order to better reflect the performance of this type of cable material under real fire conditions, a vertical combustion test is usually carried out. The low smoke ability refers to less soot generated during combustion, that is, a higher light transmittance (visibility). The purpose is to generate less soot after the non-metallic material on the outer layer of the cable burns under fire conditions, with higher visibility on-site and no impact on personnel evacuation. Existing test devices are often carried out inside a combustion chamber.

[0003] For example, the Chinese patent with the application number CN202022555227.6 discloses a cable combustion smoke density detection device, including a combustion chamber, a detection component, a translation component, and a cleaning component. The inner surface of the plate body is fixed with bristles, and the bristles are attached to the surface of the partition glass window. By cleaning the surface of the partition glass window with the bristles, the removal of surface smoke and dust is realized, the detection accuracy is improved, and it is convenient to operate and use. However, when a cable burns during actual application in a relatively large space, since the smoke generated by combustion is usually hotter and less dense than the surrounding air, the movement of the smoke will float upward under the influence of thermal buoyancy. When performing optical density detection in this detection device, due to the fixed space of the combustion chamber, this actual thermal buoyancy effect will be weakened, resulting in a light transmission path with a relatively high and fixed position and a short optical path length, which cannot effectively create actual cable combustion conditions, and the test data obtained is distorted. Summary of the Invention

[0004] In view of this, the purpose of the present invention is to provide a vertical combustion test device for electric wires and cables to solve the technical problem that in the existing detection device, due to the fixed space of the combustion chamber, the thermal buoyancy effect will be weakened, resulting in a light transmission path with a relatively high and fixed position and a short optical path length, which cannot effectively create actual cable combustion conditions, and the test data obtained is distorted.

[0005] Based on the above purpose, the present invention provides a vertical combustion test device for electric wires and cables, including a light-shielding test chamber, a specimen rack disposed inside the light-shielding test chamber, and an igniter disposed on one side of the specimen rack. An optical path emission end is respectively disposed at the upper part of the light-shielding test chamber and a polarized light sheet optical path receiving end is disposed at the lower part. There are two optical path receiving ends, and the two optical path receiving ends respectively form an extended light transmission path with the optical path emission end through a plurality of reflectors arranged in a staggered and opposite manner. The test device further includes:

[0006] A scraping plate disposed inside the light-shielding test chamber, the scraping plate being adapted to cooperate with the mirror surface of the reflecting mirror;

[0007] A driving part for driving the uppermost reflecting mirror to rotate to alternately change the light transmission optical path, and simultaneously driving the scraping plate to move up and down to clean the surface of the reflecting mirror;

[0008] A smoke exhaust chamber disposed at the upper end of the light-shielding test chamber, a valve being provided at the upper end of the smoke exhaust chamber, and a piston plate being provided inside the smoke exhaust chamber;

[0009] A transmission part for driving the piston plate to move up and down to form a negative pressure environment in the upper region of the inner cavity of the light-shielding test chamber.

[0010] Further, the specimen holder includes clamping jaws disposed inside the light-shielding test chamber for clamping electric wires and cables, a fixing frame disposed inside the light-shielding test chamber, and the clamping jaws being hinged to the fixing frame;

[0011] A abutting head slidably disposed on the fixing frame and adapted to cooperate with the outer end surface of the electric wire and cable, a connecting rod being hinged to one end of the abutting head, and the other end of the connecting rod being hinged to the middle of the clamping jaw;

[0012] A sliding rod slidably disposed at the other end of the abutting head, and a spring being sleeved on the sliding rod between the two abutting heads.

[0013] Further, the driving part includes:

[0014] A driving motor disposed outside the light-shielding test chamber through a mounting seat;

[0015] A driving gear eccentrically disposed at the output end of the driving motor;

[0016] A driven gear slidably disposed on the mounting seat, the driven gear being meshed with the driving gear and connected through a coupling member;

[0017] A guiding groove disposed on the mounting seat, a lifting frame being slidably disposed in the guiding groove, and the scraping plate being disposed on the lifting frame;

[0018] A slider eccentrically and rotatably disposed at the side end of the driven gear, the slider being slidably disposed inside the lifting frame;

[0019] A push-pull rod hinged to the upper end of the slider, the push-pull rod being inserted into the upper part of the uppermost reflecting mirror.

[0020] Further, several of the reflecting mirrors located at the lower part are all disposed inside the light-shielding test chamber through fixing plates, and the fixing plates are connected to the backs of the reflecting mirrors.

[0021] Further, the scraping plate is made of a light-transmitting material and is detachably arranged on the lifting frame.

[0022] Further, the transmission part includes;

[0023] A T-shaped abutting plate fixed to the piston plate at the top, and the lower end of the abutting plate abuts against the highest point of the coupling member;

[0024] Guide rods arranged on both sides of the abutting plate, the guide rods are slidably arranged on the smoke exhaust cavity, an extension section is arranged at the lower end of the smoke exhaust cavity, and an air vent is arranged between adjacent extension sections.

[0025] Further, when the piston plate slides down, the valve closes. After the piston plate slides to the extension section, the gas in the upper area of the inner cavity of the light-shielding test chamber is placed into the smoke exhaust cavity through the air vent.

[0026] Further, when the piston plate slides up to disengage from the extension section, the air vent closes and the valve opens.

[0027] Further, a smoke sensor is arranged on the valve. When smoke is detected to be discharged, the valve closes.

[0028] Further, when the uppermost reflector is not rotated, the light-transmitting optical path is received by the upper optical path receiving end. When the uppermost reflector is rotated, the light-transmitting optical path is received by the lower optical path receiving end.

[0029] The beneficial effects of the present invention: During use, the test wire and cable sample is fixed by the sample rack and ensured to be vertically arranged. The optical path transmitting end and the driving part are started synchronously. The light passes through several reflectors arranged in a staggered and opposite manner, and is reflected multiple times in the smoke in the light-shielding test chamber with a limited space to form an extended light-transmitting optical path. The driving part is used to drive the uppermost reflector to perform a fixed-angle flipping rotation to form an alternately changing light-transmitting optical path. The scraping plate can also be driven to clean the surfaces of each reflector in a timely manner. And with the cooperation of the driving part and the transmission part, a negative pressure environment is formed in the upper area of the inner cavity of the light-shielding test chamber to simulate the combustion situation of the wire and cable under actual installation conditions. The negative pressure environment forms an upward suction effect on the smoke inside the light-shielding test chamber similar to a chimney, ensuring the authenticity of the test data measured. Description of the Drawings

[0030] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following will briefly introduce the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings in the following description are only those of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0031] Figure 1 is a schematic diagram of the external structure of the present invention;

[0032] Figure 2 is a schematic diagram of the internal structure of the present invention;

[0033] Figure 3 is Figure 2 an enlarged view of the structure at position A in

[0034] Figure 4 is a schematic diagram of the clamping and positioning state of the wire and cable specimen on the specimen holder in the present invention;

[0035] Figure 5 is a schematic diagram of the assembly of the driving part, the uppermost reflector and the scraping plate in the present invention;

[0036] Figure 6 is a schematic diagram of the installation state of the scraping plate on the lifting frame in the present invention;

[0037] Figure 7 is a schematic diagram of the assembly of the transmission part and the piston plate in the present invention;

[0038] Figure 8 is a schematic diagram of the abutting state of the coupling member and the abutting plate in the present invention;

[0039] Figure 9 is a schematic diagram of a path for extending the light transmission path in the present invention;

[0040] Figure 10 is a schematic diagram of another path for extending the light transmission path in the present invention.

[0041] In the figure, the labels are:

[0042] 1, light-shielding test chamber; 2, igniter; 3, light path emission end; 4, light path receiving end; 5, reflector; 6, scraping plate; 7, smoke exhaust cavity; 8, valve; 9, piston plate; 10, clamping jaw; 11, fixing bracket; 12, abutting head; 13, connecting rod; 14, sliding rod; 15, spring; 16, driving motor; 17, driving gear; 18, driven gear; 19, coupling member; 20, guide groove; 21, lifting frame; 22, slider; 23, push-pull rod; 24, fixing plate; 25, abutting plate; 26, guide rod; 27, extension section; 28, smoke sensor. Specific embodiments

[0043] In order to make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below in conjunction with specific embodiments.

[0044] It should be noted that, unless otherwise defined, the technical terms or scientific terms used in the present invention shall have the ordinary meanings understood by those with ordinary skills in the field to which the present invention pertains. The "first", "second" and similar terms used in the present invention do not denote any order, quantity or importance, but are only used to distinguish different components. The terms such as "comprising" or "including" mean that the elements or objects appearing before this word cover the elements or objects listed after this word and their equivalents, without excluding other elements or objects. The terms such as "connected" or "coupled" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. The terms such as "upper", "lower", "left" and "right" are only used to represent relative positional relationships, and when the absolute position of the object being described changes, the relative positional relationship may also change accordingly.

[0045] In the first aspect of the present invention, a vertical burning test device for wire and cable is proposed. As Figures 1-10 shown, it includes a light-shielding test chamber 1, a specimen rack disposed in the light-shielding test chamber 1, and an igniter 2 disposed on one side of the specimen rack. An optical path transmitting end 3 is respectively disposed at the upper part of the light-shielding test chamber 1, and a polarized-light sheet optical path receiving end 4 is disposed at the lower part. There are two of the optical path receiving ends 4, and the two optical path receiving ends 4 respectively form an extended light-transmitting optical path with the optical path transmitting end 3 through a plurality of misaligned and oppositely arranged reflecting mirrors 5. The test device further includes:

[0046] A scraping plate 6 disposed in the light-shielding test chamber 1, and the scraping plate 6 is matched with the mirror surface of the reflecting mirror 5;

[0047] A driving part for driving the uppermost reflecting mirror 5 to rotate to alternately change the light-transmitting optical path, and at the same time driving the scraping plate 6 to move up and down to clean the surface of the reflecting mirror 5;

[0048] An exhaust chamber 7 disposed at the upper end of the light-shielding test chamber 1, a valve 8 is disposed at the upper end of the exhaust chamber 7, and a piston plate 9 is disposed inside the exhaust chamber 7;

[0049] A transmission part for driving the piston plate 9 to move up and down to form a negative pressure environment in the upper region of the inner cavity of the light-shielding test chamber 1.

[0050] In this embodiment, during use, first open the side door of the light-shielding test chamber 1, fix the wire and cable specimen to be tested through the specimen rack and ensure its vertical arrangement to simulate the installation situation of the wire and cable in the actual application process, and then close the light-shielding test chamber 1 and ignite and burn the row of wire and cables by the igniter 2;

[0051] Subsequently, the optical path transmitting end 3 and the driving part are started synchronously. The light emitted by the optical path transmitting end 3 passes through several reflectors 5 arranged in a staggered and opposite direction, and after multiple reflections in the smoke in the limited space light-shielding test chamber 1, it is received by a corresponding optical path receiving end 4 arranged at the lower part of the light-shielding test chamber 1 to form an extended light-transmitting optical path. The driving part is used to drive the uppermost reflector 5 to rotate by a fixed angle, so that the optical path reflected by this reflector 5 changes, that is, it shoots onto another corresponding reflector 5, and finally is received by another corresponding optical path receiving end 4 arranged at the lower part of the light-shielding test chamber 1 to form an alternately changing light-transmitting optical path. At the same time, driven by the driving part, the scraping plate 6 can also be driven to perform a reciprocating lifting action on the surface of each reflector 5 to clean its surface in a timely manner;

[0052] Moreover, under the cooperation of the driving part and the transmission part, the piston plate 9 can perform a reciprocating lifting action in the smoke exhaust chamber 7 to form a negative pressure environment in the upper region of the inner cavity of the light-shielding test chamber 1, so as to simulate the situation of a wire and cable burning under actual installation conditions. Under the negative pressure environment, an upward suction effect similar to that of a chimney is formed on the smoke inside the light-shielding test chamber 1 until it is detected that there is smoke exhausting, and then the light-shielding test chamber 1 is closed, effectively creating actual cable burning conditions.

[0053] In this embodiment, as Figure 2 、 Figure 4 shown, the specimen holder includes a clamping jaw 10 arranged in the light-shielding test chamber 1 for clamping a wire and cable, and a fixing frame 11 arranged in the light-shielding test chamber 1. The clamping jaw 10 is hinged to the fixing frame 11;

[0054] A abutting head 12 that cooperates with the outer end face of the wire and cable is also slidably arranged on the fixing frame 11. One end of the abutting head 12 is hinged with a connecting rod 13, and the other end of the connecting rod 13 is hinged with the middle part of the clamping jaw 10;

[0055] A sliding rod 14 is slidably arranged at the other end of the abutting head 12, and a spring 15 is sleeved on the sliding rod 14 between the two abutting heads 12;

[0056] The concave inner surface of the clamping jaw 10 can be suitable for wire and cable specimens of different specifications, and under the action of the self-elastic force of the spring 15, it can firmly clamp them, and the abutting head 12 keeps abutting against the side end face of the wire and cable specimen, so that the wire and cable specimen can maintain a vertical state, avoiding the wire and cable specimen being bent under the application of too tight clamping force and affecting the accuracy of the test results.

[0057] In this embodiment, as Figure 2 、 Figure 5 、 Figure 7 、 Figure 8 shown, the driving part includes:

[0058] A drive motor 16 installed outside the light-shielding test chamber 1 through a mounting base;

[0059] A driving gear 17 eccentrically arranged at the output end of the drive motor 16;

[0060] A driven gear 18 slidably arranged on the mounting base, the driven gear 18 meshes with the driving gear 17 and is connected by a coupling member 19;

[0061] A guide groove 20 arranged on the mounting base, a lifting frame 21 is slidably arranged in the guide groove 20, and a scraping plate 6 is arranged on the lifting frame 21;

[0062] A slider 22 eccentrically and rotatably arranged at the side end of the driven gear 18, the slider 22 is slidably arranged in the lifting frame 21;

[0063] A push-pull rod 23 hinged to the upper end of the slider 22, the push-pull rod 23 is inserted into the upper part of the uppermost reflector 5;

[0064] The output end of the drive motor 16 drives the driving gear 17 to rotate. The rotation of the driving gear 17 will drive the driven gear 18 to rotate, and through the coupling member 19, it will also drive the driven gear 18 to reciprocate on the mounting base. The rotation of the driven gear 18 will drive the slider 22 to reciprocate in the lifting frame 21, so as to drive the lifting frame 21 to reciprocate up and down on the guide groove 20, and then drive the scraping plate 6 to continuously clean the surface of the reflector 5;

[0065] At the same time, during the process of the slider 22 reciprocating in the lifting frame 21, it will also drive the push-pull rod 23 to slide on the upper part of the uppermost reflector 5, thereby adjusting the orientation of the uppermost reflector 5 to achieve the purpose of alternately changing the light transmission path.

[0066] In this embodiment, as Figure 5 shown, several reflectors 5 located at the lower part are all arranged in the light-shielding test chamber 1 through fixing plates 24. The fixing plates 24 are connected to the back of the reflectors 5. By increasing or decreasing the fixing plates 24 with reflectors 5, and adjusting the installation height of the fixing plates 24 in the light-shielding test chamber 1, the light path propagation path can be changed again specifically.

[0067] In this embodiment, as Figure 5 、 Figure 6 shown, the scraping plate 6 is made of a light-transmitting material and is detachably arranged on the lifting frame 21. The cleaning process of the scraping plate 6 on the reflector 5 will not affect the light transmission effect.

[0068] In this embodiment, as Figure 7 、 Figure 8 shown, the transmission part includes;

[0069] The T-shaped abutting plate 25 fixed to the top with the piston plate 9, and the lower end of the abutting plate 25 abuts against the highest point of the coupling member 19;

[0070] The guide rods 26 provided on both sides of the abutting plate 25, the guide rods 26 are slidably arranged on the smoke exhaust cavity 7, an extension section 27 is provided at the lower end of the smoke exhaust cavity 7, and an air vent is provided between adjacent extension sections 27;

[0071] The movement of the coupling member 19 will push against the abutting plate 25, and with the guidance of the guide rods 26 on the abutting plate 25, the abutting plate 25 can perform reciprocating lifting movements;

[0072] When the piston plate 9 slides down, the valve 8 closes. After the piston plate 9 slides to the extension section 27, the gas in the upper region of the inner cavity of the light-shielding test chamber 1 is placed into the smoke exhaust cavity 7 through the air vent, thereby realizing the formation of a negative pressure environment in the upper region of the inner cavity of the light-shielding test chamber 1 to suck the air in the light-shielding test chamber 1, forcing the smoke generated by the combustion of the wire and cable to spread vertically upward.

[0073] When the piston plate 9 slides up to disengage from the extension section 27, the air vent closes, the valve 8 opens, the piston plate 9 sliding up will push the air in the smoke exhaust cavity 7 and discharge it outside the test equipment through the valve 8. A smoke sensor 28 is provided on the valve 8. When it detects that there is smoke discharged, the valve 8 closes to avoid the smoke overflowing and affecting the accuracy of the test data.

[0074] In this embodiment, as Figure 9 、 Figure 10 shown, when the uppermost reflector 5 does not rotate, the light transmission optical path is received by the upper optical path receiving end 4. When the uppermost reflector 5 rotates, the light transmission optical path is received by the lower optical path receiving end 4. The light transmission optical path always passes through the smoke environment generated by the combustion of the wire and cable specimen, and the light transmission optical path is alternately changed under the condition of increasing the optical path, avoiding the deviation of the test result data caused by the unstable diffusion of the smoke.

[0075] Those of ordinary skill in the art should understand that: the discussion of any above embodiment is only exemplary and is not intended to imply that the scope of the present invention includes the claims being limited to these examples; under the idea of the present invention, the technical features in the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations in different aspects of the present invention as above, and they are not provided in detail for the sake of brevity.

[0076] The present invention aims to cover all such substitutions, modifications and variations that fall within the broad scope of the appended claims. Therefore, any omission, modification, equivalent substitution, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A vertical combustion test device for wire and cable, comprising a light-shielding test chamber (1), a specimen holder disposed within the light-shielding test chamber (1), and an igniter (2) disposed on one side of the specimen holder, an optical path transmitting end (3) disposed at the upper part of the light-shielding test chamber (1) and a polarized-light-filter-equipped optical path receiving end (4) disposed at the lower part of the light-shielding test chamber (1), characterized in that, There are two optical path receiving ends (4). The two optical path receiving ends (4) respectively form an extended light transmission optical path with the optical path transmitting end (3) through a plurality of misaligned and facing-opposite reflectors (5). The test equipment further includes: A scraping plate (6) disposed inside the light-shielding test chamber (1), and the scraping plate (6) is matched with the mirror surface of the reflector (5); A driving part for driving the uppermost reflector (5) to rotate to alternately change the light transmission optical path, and at the same time driving the scraping plate (6) to move up and down to clean the surface of the reflector (5); A smoke exhaust chamber (7) disposed at the upper end of the light-shielding test chamber (1). A valve (8) is provided at the upper end of the smoke exhaust chamber (7), and a piston plate (9) is provided inside the smoke exhaust chamber (7); A transmission part for driving the piston plate (9) to move up and down to form a negative pressure environment in the upper region of the inner cavity of the light-shielding test chamber (1).

2. The vertical combustion test equipment for wire and cable according to claim 1, wherein, The specimen holder includes a jaw (10) disposed inside the light-shielding test chamber (1) for clamping the wire and cable, and a fixing frame (11) disposed inside the light-shielding test chamber (1). The jaw (10) is hinged to the fixing frame (11); A abutting head (12) slidably disposed on the fixing frame (11) and matched with the outer end face of the wire and cable. One end of the abutting head (12) is hinged with a connecting rod (13), and the other end of the connecting rod (13) is hinged with the middle part of the jaw (10); A sliding rod (14) slidably disposed at the other end of the abutting head (12). A spring (15) is sleeved on the sliding rod (14) between the two abutting heads (12).

3. The vertical burning test equipment for wire and cable according to claim 1, characterized in that, The driving part includes: A driving motor (16) disposed outside the light-shielding test chamber (1) through a mounting seat; A driving gear (17) eccentrically disposed at the output end of the driving motor (16); A driven gear (18) slidably disposed on the mounting seat. The driven gear (18) is engaged with the driving gear (17) and is connected through a coupling member (19); A guiding groove (20) disposed on the mounting seat. A lifting frame (21) is slidably disposed in the guiding groove (20), and the scraping plate (6) is disposed on the lifting frame (21); A slider (22) eccentrically rotatably disposed at the side end of the driven gear (18). The slider (22) is slidably disposed inside the lifting frame (21); A push-pull rod (23) hinged to the upper end of the slider (22). The push-pull rod (23) is inserted into the upper part of the uppermost reflector (5).

4. An electric wire and cable vertical combustion test device according to claim 3, characterized in that, A plurality of the reflectors (5) located at the lower part are all disposed inside the light-shielding test chamber (1) through fixing plates (24). The fixing plates (24) are connected to the back of the reflectors (5).

5. The vertical combustion test equipment for wire and cable according to claim 3, characterized in that, The scraping plate (6) is made of a light-transmitting material and is detachably disposed on the lifting frame (21).

6. The vertical combustion test equipment for wire and cable according to claim 3, characterized in that, The transmission part includes; A T-shaped abutting plate (25) with the top fixed to the piston plate (9). The lower end of the abutting plate (25) abuts against the highest point of the coupling member (19); Guide rods (26) provided on both sides of the abutting plate (25), the guide rods (26) are slidably provided on the smoke exhaust cavity (7), an extension section (27) is provided at the lower end of the smoke exhaust cavity (7), and an air vent opening is provided between adjacent extension sections (27).

7. The vertical burning test equipment for wire and cable according to claim 6, characterized in that, When the piston plate (9) slides down, the valve (8) closes. After the piston plate (9) slides to the extension section (27), the gas in the upper region of the inner cavity of the light-shielding test chamber (1) is placed into the smoke exhaust cavity (7) through the air vent opening.

8. The vertical combustion test equipment for wire and cable according to claim 6, characterized in that, When the piston plate (9) slides up to disengage from the extension section (27), the air vent opening closes and the valve (8) opens.

9. The vertical combustion test equipment for wire and cable according to claim 6, characterized in that, A smoke sensor (28) is provided on the valve (8), and when smoke is detected to be discharged, the valve (8) closes.

10. The vertical burning test equipment for wire and cable according to claim 1, characterized in that, When the uppermost reflector (5) is not rotated, the light transmission optical path is received by the upper optical path receiving end (4). When the uppermost reflector (5) rotates, the light transmission optical path is received by the lower optical path receiving end (4).

Images