Emergency protection device for dehydrator screw conveyor

Abstract

The invention discloses an emergency protection device for a dehydrator screw conveyor, which is different from the situation that an emergency stop button is correspondingly arranged beside the screw conveyor at present, and an operation area capable of carrying out emergency stop control is small, and is connected with a trigger switch through a rope, so that the operable area of the trigger switch is effectively expanded; the rope is arranged to extend in the length direction of the spiral conveyor, the positions close to the spiral conveyor are all located in the operable area, the rope is higher than the spiral conveyor through the support, workers can conveniently pull the rope with hands to trigger the trigger switch, and therefore in the normal production and maintenance process of the spiral conveyor, the safety of the workers is improved. When foreign matters, clothes corners and even limbs of a worker are wound into the spiral conveyor due to misoperation of the worker, the worker can trigger the trigger switch by pulling the rope at any position near the spiral conveyor, so that the spiral conveyor is stopped in time, the severity of a safety event is prevented from being aggravated, and the safety of the worker is ensured. The sludge treatment stability and safety are favorably improved.

Description

Technical Field

[0001] The invention belongs to the technical field of sludge treatment devices, and in particular relates to an emergency protection device for a screw conveyor of a dehydrator. Background Art

[0002] In order to facilitate the transportation and reuse of sludge, sewage treatment plants usually transport sludge mixed with a large amount of sewage to the sludge dewatering machine in the dewatering room, so that the sludge enters the sludge dewatering machine from the feed port. The motor of the sludge dewatering machine drives the filter cloth through the wave path formed by the staggered squeezing rollers through the driving roller, thereby squeezing and filtering out most of the water in the sludge to obtain relatively dry sludge residue. Finally, the sludge residue is discharged from the discharge port of the sludge dewatering machine to complete the dehydration of the sludge.

[0003] For example, Chinese patent CN111847824A discloses a three-stage dehydration and drying system and method for sludge in a domestic sewage treatment plant, and Chinese patent CN205473318U discloses a secondary deep dehydration device for dehydrated sludge. In order to facilitate the transportation of the sludge discharged from the sludge dehydrator to the outside of the dehydration room for transportation or secondary treatment of the sludge, a screw conveyor is generally provided below the discharge port of the sludge dehydrator. The screw conveyor includes a U-shaped casing with an upward mouth and a transverse extension for receiving the discharged sludge. A screw rod is provided in the casing along the length direction. The screw rod is driven by a motor provided at the end of the casing to be used for screw conveying the sludge in the casing. During the normal production and maintenance of the screw conveyor, foreign objects, corners of the workers' clothes, or even limbs may occasionally be caught in the screw conveyor due to misoperation by the staff, resulting in safety incidents such as equipment failure or personal injury. Although the screw conveyor is generally equipped with an emergency stop button, the screw conveyor is relatively long. When a safety incident occurs, it is easy for the staff to be far away from the emergency stop button and find it difficult or even impossible to press the emergency stop button in time, which aggravates the severity of the safety incident. Therefore, in order to improve the stability and safety of sludge treatment, the use of the screw conveyor needs to be rectified and optimized. Summary of the invention

[0004] In view of the above-mentioned deficiencies in the prior art, the object of the present invention is to provide an emergency protection device for a screw conveyor for a dewatering machine, so as to solve the technical problem of poor safety in the use of the screw conveyor for the dewatering machine and achieve the effect of improving the stability and safety of sludge treatment.

[0005] In order to solve the above technical problems, the present invention adopts the following technical solutions: An emergency protection device for a dehydrator screw conveyor comprises a screw conveyor and an emergency protection unit. The screw conveyor is arranged horizontally. The emergency protection unit comprises two brackets arranged at intervals along the length direction of the screw conveyor. A trigger switch is provided on one bracket. The trigger switch is electrically connected to a control circuit of the screw conveyor and stops the screw conveyor when triggered. The trigger switch comprises an action part for triggering. A rope is connected between the action part and the other bracket. The trigger switch is triggered when the action part is pulled by the rope. The rope is located above the screw conveyor so that the screw conveyor can be stopped by pulling it in time when a safety incident occurs.

[0006] Furthermore, the control circuit includes a main control circuit, a sub-control circuit and a drive circuit for powering the motor of the screw conveyor. The main control circuit is connected in series with a normally closed push button switch, a normally open push button switch, a contactor and a normally open contact of an intermediate relay. The normally open main contact of the contactor is connected in series in the drive circuit, and the normally open sub-contact of the contactor is connected in parallel with the normally open push button switch; the trigger switch is in a normally closed state and is connected in series with the intermediate relay in the sub-control circuit.

[0007] Furthermore, the auxiliary control circuit includes a first branch and a second branch connected in parallel, the trigger switch and the intermediate relay are connected in series on the first branch, and the normally closed contact of the intermediate relay and the sound and light alarm are connected in series on the second branch.

[0008] Furthermore, the trigger switch adopts a fire-off limiter, and a push-pull rod of the fire-off limiter is connected to the rope as the acting part.

[0009] Furthermore, the support is erected and fixed on the ground, and the rope is a steel wire rope.

[0010] Optionally, the emergency protection unit has one and two brackets are located at both ends of the screw conveyor.

[0011] Optionally, there are multiple emergency protection units and they are arranged continuously along the length direction of the screw conveyor, and there are two brackets located at both ends of the screw conveyor.

[0012] Furthermore, the emergency protection device also includes a sludge dewatering machine, the discharge port of the sludge dewatering machine is located on one side of the length direction of the sludge dewatering machine, the screw conveyor is located close to the sludge dewatering machine and on the side where the discharge port is located, the length direction of the screw conveyor corresponds to the width direction of the sludge dewatering machine, and the screw conveyor is lower than the discharge port.

[0013] Furthermore, the screw conveyor includes a casing with a U-shaped cross-section and an upward mouth, and a guide plate is obliquely provided between the casing mouth and the discharge port to guide the mud discharged from the discharge port into the casing, and the rope is higher than the guide plate.

[0014] Compared with the prior art, the present invention has the following beneficial effects: 1. The emergency protection device for the screw conveyor of the dewatering machine described in the present invention is different from the current emergency stop button arranged next to the screw conveyor, and the operating area for emergency stop control is small. The present invention uses a rope to connect the trigger switch, which effectively expands the operable area of ​​the trigger switch. The rope is arranged to extend along the length direction of the screw conveyor so that the positions close to the screw conveyor are all in the operable area. The rope is made higher than the screw conveyor by a bracket, so that the staff can pull the rope by hand to trigger the trigger switch. It can effectively solve the problem of poor safety in the use of the screw conveyor for the dewatering machine, which is beneficial to improving the stability and safety of sludge treatment.

[0015] 2. The emergency protection device for the screw conveyor of the dehydrator described in the present invention, through circuit design, can ensure that after the rope is pulled and then released, the motor of the screw conveyor will not continue to work, which is convenient for the staff to escape or handle faults; by setting an audible and visual alarm, it can remind nearby staff in the form of sound and light effects after the rope is pulled, so as to ensure that safety incidents and faults are handled in time, so that the emergency protection device has good reliability and practicality. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 A top view of the emergency protection device for the screw conveyor of the dehydrator according to the embodiment; Figure 2 A three-dimensional diagram of the emergency protection device for the screw conveyor of the dehydrator according to the embodiment; Figure 3 It is a wiring diagram of the control circuit described in the embodiment; Among them, there are a screw conveyor 1, a bracket 2, a trigger switch 3, a rope 4, a sludge dewatering machine 5, a discharge port 6, a guide plate 7, a material receiving funnel 8, and a motor 9. DETAILED DESCRIPTION

[0017] To make the purpose, technical solution and advantages of the embodiments of the present invention more clear, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0018] Example: See also Figure 1 and Figure 2An emergency protection device for a dehydrator screw conveyor comprises a screw conveyor 1 and an emergency protection unit. The screw conveyor 1 is arranged horizontally. The emergency protection unit comprises two brackets 2 arranged at intervals along the length direction of the screw conveyor 1. A trigger switch 3 is arranged on one bracket 2. The trigger switch 3 is electrically connected to the control circuit of the screw conveyor 1 and stops the screw conveyor 1 when triggered. The trigger switch 3 comprises an action part for triggering. A rope 4 is connected between the action part and the other bracket 2. The trigger switch 3 is triggered when the action part is pulled by the rope 4. The rope 4 is located directly above the screw conveyor 1. During implementation, the height of the rope 4 should be reasonably set according to the range of vertical hand movement of the staff when standing, so that the rope 4 can be pulled in time to stop the screw conveyor 1 when a safety incident occurs.

[0019] The emergency protection device for the screw conveyor of the dewatering machine described in the present invention is different from the current emergency stop button corresponding to the screw conveyor 1, and the operating area for emergency stop control is small. The emergency protection device of the present invention connects the trigger switch 3 with a rope 4, which effectively expands the operable area of ​​the trigger switch 3, and sets the rope 4 to extend along the length direction of the screw conveyor 1, so that the positions close to the screw conveyor 1 are all in the operable area. The rope 4 is made higher than the screw conveyor 1 through the bracket 2, so that the staff can pull the rope 4 by hand to trigger the trigger switch 3. In this way, during the normal production and maintenance of the screw conveyor 1, due to the staff's misoperation, foreign objects, the corners of the staff's clothes, or even limbs are involved in the screw conveyor 1. The staff can trigger the trigger switch 3 by pulling the rope 4 at any place near the screw conveyor 1, thereby stopping the screw conveyor 1 in time and avoiding the severity of the safety incident from being aggravated. Therefore, the emergency protection device of the present invention can effectively solve the problem of poor safety of the screw conveyor for the dewatering machine, which is beneficial to improving the stability and safety of sludge treatment.

[0020] See also Figure 3 The control circuit includes a main control circuit, a sub-control circuit and a drive circuit for powering the motor M of the screw conveyor. The main control circuit is connected in series with a normally closed push button switch SB1, a normally open push button switch SB2, a contactor KM and a normally open contact of an intermediate relay KA. The normally open main contact of the contactor KM is connected in series in the drive circuit, and the normally open sub-contact of the contactor KM is connected in parallel with the normally open push button switch SB2; the trigger switch SQ is in a normally closed state and is connected in series with the intermediate relay KA in the sub-control circuit.

[0021] The working principle of the control circuit is that the auxiliary control circuit remains conducting under normal conditions, the intermediate relay KA is energized, and the normally open contact of the intermediate relay KA remains closed; after pressing the normally open push button switch SB2, the main control circuit is conducted, the contactor KM is energized, the normally open main contact of the contactor KM is closed to connect the drive circuit, the motor M of the screw conveyor is energized to work, and at the same time, the normally open auxiliary contact of the contactor KM is closed to complete self-locking; When the trigger switch SQ is triggered by pulling the rope, the normally closed trigger switch SQ is disconnected, the auxiliary control circuit is disconnected, the intermediate relay KA loses power, the normally open contact of the intermediate relay KA is disconnected, the main control circuit is disconnected, the contactor KM loses power, the normally open main contact of the contactor KM closes and disconnects again, the drive circuit is disconnected, the motor M of the screw conveyor loses power and stops, thereby avoiding the severity of the accident. At the same time, the normally open auxiliary contact of the contactor KM is disconnected, and the self-locking is released; at this time, the rope is loosened and the motor M of the screw conveyor will not continue to work; After the rope is released, the normally closed trigger switch SQ returns to the closed state, the auxiliary control circuit returns to the conductive state, and the intermediate relay KA is energized, so that the normally open contacts of the intermediate relay KA remain closed in preparation for restarting; when the event is resolved or the fault is restored, the normally open push button switch SB2 can be pressed again to start the screw conveyor.

[0022] See also Figure 3 The auxiliary control circuit includes a first branch and a second branch connected in parallel. The trigger switch SQ and the intermediate relay KA are connected in series on the first branch, and the normally closed contact of the intermediate relay KA and the sound and light alarm BSG are connected in series on the second branch.

[0023] In this way, the auxiliary control circuit remains turned on under normal conditions, the intermediate relay KA is energized, the normally closed contact of the intermediate relay KA remains disconnected, and the second branch is disconnected; the rope is pulled to trigger the trigger switch SQ, and the normally closed trigger switch SQ is disconnected, so that the auxiliary control circuit is disconnected. When the intermediate relay KA loses power, the normally closed contact of the intermediate relay KA closes, the second branch is turned on, and the sound and light alarm BSG is energized and works, emitting an alarm sound and light effect, thereby alerting nearby personnel to deal with safety incidents or faults in a timely manner.

[0024] In this embodiment, the trigger switch 3 adopts a fire-off limiter, and the push-pull rod of the fire-off limiter serves as the acting part and is connected to the rope 4; due to the difference in structural design, the fire-off limiter is not only more stable and durable than the ordinary travel switch, but also has stronger adaptability to the environment. It can maintain good performance in the harsh working environment of the sludge dewatering room, ensuring the reliability of the emergency protection device.

[0025] In this embodiment, the bracket 2 is erected and fixed on the ground, and the rope 4 is a steel wire rope; the steel wire rope is used as the rope 4 for pulling the trigger switch 3, which has good strength and durability, and can not only adapt to the harsh working environment of the sludge dewatering room, but also can facilitate the staff to escape or reduce injuries when a safety incident occurs.

[0026] In order to avoid the trigger switch 3 being triggered by the deadweight of the rope 4 or the sensitivity being too high, the number of emergency protection units should be determined according to the length of the screw conveyor 1 during implementation. When the screw conveyor 1 is long, multiple emergency protection units can be arranged continuously along the length direction of the screw conveyor 1, and ensure that there are two brackets 2 located at both ends of the screw conveyor 1, and the trigger switch 3 of each emergency protection unit is connected in series in the first branch. In this way, the weight of the rope 4 connected to the trigger switch 3 is reduced as the length is shortened; this embodiment has one emergency protection unit, and the two brackets 2 are located at both ends of the screw conveyor 1.

[0027] See also Figure 1 and Figure 2 The emergency protection device also includes a sludge dewatering machine 5, a discharge port 6 of the sludge dewatering machine 5 is located on one side of the length direction of the sludge dewatering machine 5, and a screw conveyor 1 is located near the sludge dewatering machine 5 and on the side where the discharge port 6 is located. The length direction of the screw conveyor 1 corresponds to the width direction of the sludge dewatering machine 5, and the screw conveyor 1 is lower than the discharge port 6; in this way, it is not only convenient to arrange the screw conveyor 1, but also convenient to arrange the bracket 2 and the rope 4, which is beneficial to reduce the possibility of interference between the rope 4 and the sludge dewatering machine 5.

[0028] See also Figure 1 and Figure 2 The screw conveyor 1 includes a casing with a U-shaped cross-section and an upward mouth. A guide plate 7 is obliquely provided between the casing mouth and the discharge port 6, and the rope 4 is higher than the guide plate 7; in this way, the discharge port guides the discharged sludge into the casing through the guide plate 7, so that the screw conveyor 1 is staggered with the discharge port in the vertical direction, which can reduce the possibility of interference between the sludge discharged by the sludge dewatering machine 5 and the rope 4, and avoid the rope 4 being hit by the sludge and causing the trigger switch 3 to be accidentally triggered, which is beneficial to improving the reliability of the emergency protection device.

[0029] In this embodiment, a material receiving funnel 8 is further provided at the junction of the casing mouth and the material guide plate 7 to expand the material receiving opening; the motor 9 and the trigger switch 3 of the screw conveyor 1 are at the same end to facilitate line layout, and the auxiliary control circuit adopts a switching power supply with an output of DC12V to improve the safety of the emergency protection device.

[0030] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit the technical solution. Those skilled in the art should understand that those modifications or equivalent substitutions of the technical solution of the present invention that do not depart from the purpose and scope of the technical solution should be included in the scope of the claims of the present invention.

Claims

1. An emergency protection device for a dehydrator screw conveyor, characterized in that: It includes a screw conveyor and an emergency protection unit. The screw conveyor is arranged horizontally. The emergency protection unit includes two brackets arranged at intervals along the length direction of the screw conveyor. A trigger switch is provided on one bracket. The trigger switch is electrically connected to the control circuit of the screw conveyor and stops the screw conveyor when triggered. The trigger switch includes an action part for triggering. A rope is connected between the action part and the other bracket. The trigger switch is triggered when the action part is pulled by the rope. The rope is located above the screw conveyor so that it can be pulled in time to stop the screw conveyor when a safety incident occurs.

2. According to claim 1, an emergency protection device for a dehydrator screw conveyor is characterized in that: The control circuit includes a main control circuit, a sub-control circuit and a drive circuit for powering the motor of the screw conveyor. The main control circuit is connected in series with a normally closed push button switch, a normally open push button switch, a contactor and a normally open contact of an intermediate relay. The normally open main contact of the contactor is connected in series in the drive circuit, and the normally open sub-contact of the contactor is connected in parallel with the normally open push button switch; the trigger switch is in a normally closed state and is connected in series with the intermediate relay in the sub-control circuit.

3. According to claim 2, an emergency protection device for a dehydrator screw conveyor is characterized in that: The auxiliary control circuit comprises a first branch and a second branch connected in parallel, a trigger switch and an intermediate relay are connected in series on the first branch, and a normally closed contact of the intermediate relay and an audible and visual alarm are connected in series on the second branch.

4. The emergency protection device for a dehydrator screw conveyor according to claim 1, characterized in that: The trigger switch adopts a fire-off limiter, and a push-pull rod of the fire-off limiter is connected with the rope as the action part.

5. The emergency protection device for a dehydrator screw conveyor according to claim 1, characterized in that: The bracket is erected and fixed on the ground, and the rope is made of steel wire rope.

6. The emergency protection device for a dehydrator screw conveyor according to claim 1, characterized in that: The emergency protection unit has one and two brackets located at both ends of the screw conveyor.

7. The emergency protection device for a dehydrator screw conveyor according to claim 1, characterized in that: There are multiple emergency protection units which are continuously arranged along the length direction of the screw conveyor, and there are two brackets located at both ends of the screw conveyor.

8. The emergency protection device for a dehydrator screw conveyor according to claim 1, characterized in that: The emergency protection device also includes a sludge dewatering machine, the discharge port of the sludge dewatering machine is located on one side of the length direction of the sludge dewatering machine, the screw conveyor is located close to the sludge dewatering machine and on the side where the discharge port is located, the length direction of the screw conveyor corresponds to the width direction of the sludge dewatering machine, and the screw conveyor is lower than the discharge port.

9. The emergency protection device for a dehydrator screw conveyor according to claim 8, characterized in that: The screw conveyor comprises a casing with a U-shaped cross section and an upward mouth. A guide plate is obliquely arranged between the casing mouth and the discharge port so as to guide the mud discharged from the discharge port into the casing. The rope is higher than the guide plate.

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