Double-water-pump switching device for filter press

Abstract

The utility model relates to a double-water-pump switching device for filter presses, and belongs to the field of water supply of water pumps, the double-water-pump switching device comprises two groups of filter presses, each group of filter presses is provided with a water supply pipeline, a water pump and a control valve corresponding to the water pump, and the water supply pipeline is communicated with water inlets of the filter presses; the water pump is arranged on the water supply pipeline and pumps water into the filter press through the water supply pipeline; a communicating pipeline is arranged between the two groups of water supply pipelines, and a communicating valve for controlling the two groups of water supply pipelines to communicate is arranged on the communicating pipeline; buffer tanks positioned between the control valves and the communicating pipelines are respectively arranged on the water supply pipelines; the buffer tank comprises a tank body, a water inlet and a water outlet, the water inlet is communicated with the position, close to the control valve, of the water supply pipeline, the water outlet is communicated with the position, close to the communicating pipeline, of the water supply pipeline, and the water inlet is lower than the water outlet. The filter press has the effects of ensuring continuous operation of the filter press and avoiding influence on normal production.

Description

Technical Field

[0001] The present application relates to the field of water supply by water pumps, and in particular to a dual water pump switching device for a filter press. Background Art

[0002] Filter press is a solid-liquid separation equipment widely used in various chemical industries. In the process of plastic production, some waste liquid or wastewater containing solid particles is often produced. Through the function of filter press, these waste liquid or wastewater can be effectively separated into solid and liquid parts, which is convenient for subsequent treatment and utilization.

[0003] At present, in actual work, two filter presses are set up in parallel. Each filter press is provided with a water inlet and connected to an independent water supply pipeline, and water is transported to the filter press by a water pump.

[0004] With regard to the above-mentioned related technologies, when the water pump motor fails and the water pump cannot pump water, the water content in the filter press is insufficient, and the operation needs to be stopped to inspect or replace the water pump, which seriously affects the operation time and seriously causes production suspension. Utility Model Content

[0005] In order to ensure the continuous operation of the filter press and avoid affecting normal production, the present application provides a dual water pump switching device for the filter press.

[0006] The present application provides a dual water pump switching device for a filter press using the following technical solution:

[0007] It comprises two groups of filter presses, each group of filter presses is respectively provided with a water supply pipeline, a water pump and a control valve, the water supply pipeline is connected to the water inlet of the filter press; the water pump is arranged on the water supply pipeline, the water pump pumps water into the filter press through the water supply pipeline, and the control valve is arranged at the water supply pipeline near the water outlet end of the water pump; a connecting pipeline is arranged between the two groups of water supply pipelines, the two ends of the connecting pipeline are respectively connected to the two groups of pipelines located between the control valve and the filter press, a connecting valve is arranged on the connecting pipeline, and the connecting valve controls whether the two groups of water supply pipelines are connected; buffer tanks are respectively arranged on the water supply pipelines, and the buffer tanks are all located between the control valve and the connecting pipeline; the buffer tank comprises a tank body, a water inlet and a water outlet, the water inlet is connected to the water supply pipeline near the control valve, the water outlet is connected to the water supply pipeline near the connecting pipeline, and the water inlet is arranged lower than the water outlet.

[0008] By adopting the above technical solution, the two filter presses contain two sets of independent water supply pipes, water pumps and control valves, which can realize efficient dual water pump switching, so that one water pump can work in excess of its working power but not exceeding its rated power to drive the two sets of filter presses to work normally. This can not only ensure that the filter presses can continuously and stably obtain the required water source, but also quickly switch to another water pump when one water pump fails, thereby ensuring the continuous operation of the production line.

[0009] Optionally, the cross-sectional diameter of the water inlet is larger than the cross-sectional diameter of the water outlet.

[0010] By adopting the above technical solution, the size of the water inlet is larger than that of the water outlet, so that the water flow velocity at the water inlet is smaller than the water flow velocity at the water outlet, further reducing the impact of the water flow.

[0011] Optionally, the water inlet and the water outlet are arranged opposite to each other, and the water inlet and the water outlet are arranged on both sides of the tube body.

[0012] By adopting the above technical solution, the design of the water inlet and the water outlet being relatively far apart can effectively reduce the impact of water flow on the system, stabilize the water flow, reduce pressure fluctuations, and thus protect the system from damage.

[0013] Optionally, a manual liquid level gauge is provided in the buffer tank, and the manual liquid level gauge detects the liquid level height in the buffer tank.

[0014] By adopting the above technical solution, the manual liquid level gauge can conveniently monitor the liquid level height in the buffer tank.

[0015] Optionally, the buffer tank is conical at one end close to the ground, and a sewage pipe connected to the interior of the tank body is provided at the conical top end of the buffer tank; a sewage valve is provided at the connection position between the sewage pipe and the tank body, and the water in the tank body flows into the sewage pipe through the sewage valve.

[0016] By adopting the above technical solution, the arrangement of the sewage discharge pipe and the sewage discharge valve can conveniently discharge the sewage and impurities in the buffer tank.

[0017] Optionally, a stopper is coaxially arranged at the lower part of the buffer tank, and the stopper is in the shape of a double cone, and there is a gap between the lower cone surface of the stopper and the inner wall of the tank body, and the gap near the sewage discharge valve is smaller than the gap far from the sewage discharge valve.

[0018] By adopting the above technical solution, the gap between the lower conical surface of the block and the inner wall of the tank body is gradually reduced, thereby increasing the flow rate of water flowing through the gap, so that the water flows through the gap to peel off the sediment or impurities on the inner wall of the tank body, achieving a self-cleaning effect.

[0019] Optionally, a vent pipe is provided at a position of the tank body away from the ground, the vent pipe is higher than the water outlet, and the vent pipe connects the inside of the pipe body with the outside; a pressure relief valve is provided in the vent pipe, and the air in the tank body flows out of the pipe body through the pressure relief valve.

[0020] By adopting the above technical solution, the arrangement of the vent pipe and the pressure relief valve can keep the air pressure inside the buffer tank stable.

[0021] Optionally, a group of alarm devices are provided on the water supply pipeline, and the alarm devices are located between the connecting pipeline and the filter press; each group of alarm devices includes two parallel arranged buzzer alarms, a rotor, a connecting rod and a group of relatively arranged weights; the rotor is arranged parallel to the axis of the water supply pipeline, and the water flow in the water supply pipeline drives the rotor to rotate; a connecting rod is fixedly provided on the same axis of the rotor, and the connecting rod is upwardly penetrated through the wall of the water supply pipeline; the weight is connected to the end of the connecting rod away from the rotor, and the weight can be tilted to the axis direction of the connecting rod and swing up and down; the buzzer alarm is fixed on the outer wall of the water supply pipeline close to the position of the weight, and when the weight abuts against the buzzer alarm, the buzzer alarm sounds an alarm.

[0022] By adopting the above technical solution, the alarm device can promptly issue an alarm when the flow rate in the water supply pipe is abnormal through the combined use of a heavy hammer and a buzzer alarm. This intelligent fault alarm mechanism can not only help staff to find and deal with problems in a timely manner, but also greatly reduce the risk of equipment damage and save maintenance costs and time.

[0023] In summary, the present application includes at least one of the following beneficial technical effects:

[0024] 1. By setting up two sets of independent water supply pipes, water pumps and control valves, the device can achieve efficient dual water pump switching. This can not only ensure that the filter press can continuously and stably obtain the required water source, but also can quickly switch to another water pump when one water pump fails, thereby ensuring the continuous and normal operation of the subsequent filter press;

[0025] 2. The setting of the buffer tank helps to balance the water pressure and water flow in the water supply pipeline, reducing the impact of water hammer and pressure fluctuations on the system. At the same time, the design of the water inlet and outlet can further improve the buffering effect and protect the system from potential damage;

[0026] 3. The alarm device uses a combination of a heavy hammer and a buzzer alarm to promptly sound an alarm when the flow rate in the water supply pipe is abnormal. This intelligent fault alarm mechanism can not only help staff to find and deal with problems in a timely manner, but also greatly reduce the risk of equipment damage and save maintenance costs and time. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a structural schematic diagram of a dual water pump switching device for a filter press according to an embodiment of the present application;

[0028] Figure 2 is a cross-sectional view of a protruding buffer tank of a dual water pump switching device for a filter press according to an embodiment of the present application;

[0029] Figure 3 yes Figure 2 A partial enlarged view of middle A.

[0030] Explanation of the reference numerals in the accompanying drawings: 1. filter press; 2. water supply pipeline; 3. water pump; 31. control valve; 4. buffer tank; 41. tank body; 42. water inlet; 43. water outlet; 44. manual liquid level gauge; 45. block; 46. vent pipe; 461. pressure relief valve; 5. sewage pipe; 51. sewage valve; 6. connecting pipeline; 61. connecting valve; 7. alarm device; 71. impeller; 72. connecting rod; 73. heavy hammer; 74. buzzer alarm; 75. bracket. DETAILED DESCRIPTION

[0031] The following is combined with Figure 1-3 This application is described in further detail.

[0032] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or a communication; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0033] In the present application, unless otherwise clearly specified and limited, a first feature "above" or "below" a second feature may be that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in an appropriate manner in any one or more embodiments or examples.

[0034] The present application embodiment discloses a dual water pump switching device for a filter press. Figure 1A dual water pump switching device for a filter press includes two groups of filter presses 1. Both groups of filter presses 1 are fixedly connected with independent water supply pipelines 2. A water pump 3 is installed at a position of each water supply pipeline 2 away from the filter press 1, and the position of the water pump 3 is lower than the position of the filter press 1. The water pump 3 pumps water upward into the corresponding filter press 1 through the water supply pipeline 2. A control valve 31 is flange-connected to the water supply pipeline 2 near the position of the water pump 3. The control valve 31 can cut off the water flow into the filter press 1. During normal operation, the control valve 31 is in an open state. When the water pump 3 needs to be repaired or fails and needs to be replaced, the control valve 31 is closed to separate the water pump 3 and the water supply pipeline 2, so that the operator can easily carry out maintenance and avoid the influence of the replacement and maintenance of the water pump 3 on the water flow in the water supply pipeline 2.

[0035] A connecting pipe 6 is fixedly connected to the two water supply pipes 2, and both ends of the connecting pipe 6 are respectively fixedly connected to the two water supply pipes 2 at the positions of the control valve 31 and the filter press 1, and the connecting pipe 6 is connected to the two water supply pipes 2. A connecting valve 61 is flange-connected to the connecting pipe 6, and when the connecting valve 61 is opened, the two water supply pipes 2 are connected; when the connecting valve 61 is closed, the two water supply pipes 2 are relatively independent.

[0036] refer to Figure 1 and reference Figure 2 , buffer tanks 4 are respectively installed on the two groups of water supply pipelines 2, and the buffer tanks 4 are located between the control valve 31 and the connecting pipeline 6. The buffer tank 4 includes a tank body 41, a water inlet 42 and a water outlet 43. The water inlet 42 and the water outlet 43 are respectively set away from the ground, the water inlet 42 is connected to the water supply pipeline 2 near the control valve 31, and the water outlet 43 is connected to the water supply pipeline 2 near the connecting pipeline 6. The tank body 41 is connected to the water supply pipeline 2 through the water inlet 42 and the water outlet 43. The tank body 41 of the buffer tank 4 can absorb and store transient pressure fluctuations caused by rapid actions such as the start and stop of the water pump 3 and the switch of the valve. When the filter press 1 is in operation, the water pumped out by the water pump 3 enters the tank body 41 of the buffer tank 4 through the water inlet 42, and the water in the tank body 41 flows out from the water outlet 43 after being buffered, thereby reducing the impact and influence of the internal pressure change of the water supply pipeline 2 on the subsequent filter press 1.

[0037] refer to Figure 1 and reference Figure 2 The cross-sectional size of the water inlet 42 is larger than that of the water outlet 43. The larger cross-sectional size of the water inlet 42 allows more fluid to enter the buffer tank 4 in a short time, thereby reducing the impact of the fluid on the inside of the tank body 41. This design helps to reduce the vibration and wear of the tank body 41 and extend the service life of the buffer tank 4. In addition, the cross-sectional size of the water inlet 42 is larger than that of the water outlet 43, which can reduce the speed of the fluid entering the buffer tank 4. This helps to reduce the turbulence and eddy current of the fluid inside the tank body 41, allowing the fluid to flow more smoothly.

[0038] refer to Figure 1 and reference Figure 2 The water inlet 42 and the water outlet 43 are arranged on both sides of the tank body 41 in the radial direction, so that the water inlet 42 and the water outlet 43 are spaced farther apart, and the water entering the tank body 41 can be more evenly distributed on the entire cross section of the tank body 41, so that the water can stay in the tank body 41 for a longer time. The water inlet 42 and the water outlet 43 arranged on both sides of the tank body 41 help reduce the local concentration and eddy current of water, so that the water flows more smoothly in the tank body 41, and the buffer tank 4 can better play its buffering role. It helps to reduce the pressure fluctuation of the fluid in the tank body 41 and improve the stability of the system.

[0039] refer to Figure 1 and reference Figure 2 A manual liquid level gauge 44 is installed in the tank body 41. The manual liquid level gauge 44 is vertically arranged and vertically penetrates the inner wall of the upper end of the tank body 41. The manual liquid level gauge 44 can convert the water level in the tank body 41 into a value that is convenient for the staff to observe, so that the staff can monitor the water level changes in the tank body 41 and take timely measures to avoid the possibility of problems expanding and accidents. The manual liquid level gauge 44 is easy to install and use, and the cost of the manual liquid level gauge 44 is low. During use, the staff can directly observe the height of the liquid level in the tank body 41 without relying on electronic equipment.

[0040] refer to Figure 1 and reference Figure 2 The lower end of the tank body 41 close to the ground is set to be conical, and the tip of the cone extends downward along the axis of the tank body 41. The tip of the cone of the tank body 41 is fixedly connected to a sewage pipe 5 connected to the inside of the tank body 41. A sewage valve 51 is fixedly connected to the connection position between the sewage pipe 5 and the tank body 41, and the sewage valve 51 controls whether the sewage pipe 5 is connected to the inside of the tank body 41. It can be understood that when water enters the buffer tank 4 for treatment, the water contains impurities, and the impurities may enter the water supply pipeline 2 through the buffer tank 4, causing damage to the subsequent system. By opening the sewage valve 51, the sediment or other impurities in the tank can be quickly discharged, thereby keeping the tank clean and extending the service life of the buffer tank 4. At the same time, regular discharge can reduce the risk of these impurities entering the system.

[0041] refer to Figure 1 and reference Figure 2A stopper 45 is fixedly connected to the tank body 41 near the sewage valve 51. The stopper 45 is a double cone, and the stopper 45 is coaxially arranged with the tank body 41. The stopper 45 includes an upper cone and a lower cone. The tip of the upper cone of the stopper 45 is vertically arranged upward, and the sediment or impurities in the water slide down along the upper cone of the stopper 45, so that the sediment or impurities are not easy to accumulate. The tip of the lower cone of the stopper 45 is vertically arranged downward, and there is a gap between the lower cone of the stopper 45 and the inner wall of the tank body 41, and the gap near the sewage valve 51 is smaller than the gap away from the sewage valve 51. When the sewage valve 51 is opened for sewage discharge, the gap size between the stopper 45 near the sewage valve 51 and the inner wall of the tank body 41 gradually decreases, increasing the speed of the water flow, and the accelerated water flow peels off the sediment or impurities and the inner wall of the tank body 41, so that the tank body 41 has a self-cleaning effect.

[0042] refer to Figure 1 and reference Figure 2 A vent pipe 46 is provided on the side wall of the tank body 41. The vent pipe 46 is arranged at a position away from the ground and is higher than the height of the tank body 41. The two ends of the vent pipe 46 are respectively connected to the inside of the tank body 41 and the outside. A pressure relief valve 461 is coaxially fixedly connected in the vent pipe 46, and the pressure relief valve 461 controls the conduction of the vent pipe 46. When the water pump 3 needs to be repaired and switched, the water pressure of the water pump 3 becomes unstable. When the pressure inside the tank body 41 exceeds the maximum pressure set by the pressure relief valve 461, the pressure relief valve 461 opens to connect the inside of the tank body 41 to the outside, and releases the excessive pressure to prevent the buffer tank 4 from being damaged due to overpressure. When the pressure inside the tank body 41 is less than the maximum pressure set by the pressure relief valve 461, the pressure relief valve 461 is closed, and the inside of the tank body 41 remains closed.

[0043] refer to Figure 2 and reference Figure 3, an alarm device 7 is provided on both sets of water supply pipelines 2. The alarm device 7 is located between the connecting pipeline 6 and the filter press 1. The alarm device 7 includes two buzzer alarms 74 arranged in parallel, a rotating wheel 71, a connecting rod 72 and a group of weights 73 arranged oppositely. The rotating wheel 71 is located inside the water supply pipeline 2, and the rotating wheel 71 is arranged parallel to the axis of the water supply pipeline 2, and the water flow in the water supply pipeline 2 drives the rotating wheel 71 to rotate. The connecting rod 72 is in a vertical state, and the connecting rod 72 is rotatably connected to the water supply pipeline 2. The connecting rod 72 is perpendicular to the axis of the water supply pipeline 2, and the lower end of the connecting rod 72 is penetrated through the inner wall of the water supply pipeline 2 and is coaxially fixed to the rotating wheel 71. A weight 73 is hinged on the upper end of the connecting rod 72, and the weight 73 rotates synchronously with the connecting rod 72. During the rotation process, the weight 73 swings in a direction away from the axis of the connecting rod 72 under the action of centrifugal force. A bracket 75 is fixedly connected to the outer wall of the water supply pipeline 2 at the position corresponding to the connecting rod 72, and two buzzer alarms 74 arranged in parallel are fixedly connected to the bracket 75. The two buzzer alarms 74 are respectively located above and below the weight 73. When water is flowing through the water supply pipeline 2, the water flowing in the water supply pipeline 2 is driven to rotate by the runner 71. When the water flow velocity in the water supply pipeline 2 is higher than the predetermined flow velocity, the weight 73 rotates perpendicularly to the axis of the connecting shaft, and at this time, the weight 73 abuts against the buzzer alarm 74 above; when the water flow in the water supply pipeline 2 is lower than the predetermined flow velocity, the weight 73 rotates 45 degrees with the axis of the connecting shaft, and the weight 73 abuts against the buzzer alarm 74 below and the buzzer alarm sounds. The buzzer alarm 74 sounds to remind the operator to check whether there is any operating failure in the water pump 3 on the water supply pipeline 2, and remind the operator to check.

[0044] The implementation principle of a dual water pump switching device for a filter press in an embodiment of the present application is as follows: when the water pump 3 corresponding to one of the two filter presses 1 is under maintenance, the connecting valve 61 is opened to connect the two groups of water supply pipelines 2. Then the control valve 31 corresponding to the water pump 3 that needs to be repaired is closed, and at the same time, the first water pump 3 is operated when it exceeds its working power but does not exceed its rated power, so as to ensure that one water pump 3 can support the work of two groups of filter presses 1 at the same time. When switching the water pump 3, the buffer tank 4 effectively reduces the impact of the water flow on the system, stabilizes the water flow, reduces pressure fluctuations, and thus protects the system from damage. By setting two independent water supply pipelines, water pumps 3 and control valves 31, the device can achieve efficient switching of the dual water pumps 3. This can not only ensure that the filter press 1 continuously and stably obtains the required water source, but also can quickly switch to another water pump 3 when one water pump 3 fails, thereby ensuring the continuous and normal operation of the subsequent filter press 1.

[0045] This application ensures the continuous operation of the filter press and avoids affecting normal production.

[0046] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A dual water pump switching device for a filter press, comprising two groups of filter presses (1), each group of filter presses (1) being respectively provided with a water supply pipeline (2), a water pump (3) and a control valve (31), wherein the water supply pipeline (2) is connected to a water inlet (42) of the filter press (1); the water pump (3) is arranged on the water supply pipeline (2), and the water pump (3) pumps water into the filter press (1) through the water supply pipeline (2); the control valve (31) is arranged on the water supply pipeline (2) near the water outlet end of the water pump (3), and is characterized in that: A connecting pipeline (6) is provided between the two groups of water supply pipelines (2), and the two ends of the connecting pipeline (6) are respectively connected to the two groups of pipelines located between the control valve (31) and the filter press (1), and a connecting valve (61) is provided on the connecting pipeline (6), and the connecting valve (61) controls whether the two groups of water supply pipelines (2) are connected; buffer tanks (4) are respectively provided on the water supply pipelines (2), and the buffer tanks (4) are located between the control valve (31) and the connecting pipeline (6); the buffer tank (4) comprises a tank body (41), a water inlet (42) and a water outlet (43), the water inlet (42) is connected to the water supply pipeline (2) at a position close to the control valve (31), and the water outlet (43) is connected to the water supply pipeline (2) at a position close to the connecting pipeline (6), and the water inlet (42) is arranged lower than the water outlet (43).

2. A dual water pump switching device for a filter press according to claim 1, characterized in that: The cross-sectional diameter of the water inlet (42) is greater than the cross-sectional diameter of the water outlet (43).

3. A dual water pump switching device for a filter press according to claim 1, characterized in that: The water inlet (42) and the water outlet (43) are arranged opposite to each other, and the water inlet (42) and the water outlet (43) are arranged on two sides of the tank body (41).

4. A dual water pump switching device for a filter press according to claim 1, characterized in that: A manual liquid level meter (44) is provided in the buffer tank (4), and the manual liquid level meter (44) detects the liquid level height in the buffer tank (4).

5. A dual water pump switching device for a filter press according to claim 1, characterized in that: The buffer tank (4) is tapered at one end close to the ground, and a sewage pipe (5) connected to the interior of the tank body (41) is provided at the top of the cone of the buffer tank (4); a sewage valve (51) is provided at the connection position between the sewage pipe (5) and the tank body (41), and water in the tank body (41) flows into the sewage pipe (5) through the sewage valve (51).

6. A dual water pump switching device for a filter press according to claim 5, characterized in that: A stopper (45) is coaxially arranged in the lower part of the buffer tank (4), and the stopper (45) is in a double cone shape. A gap exists between the lower cone surface of the stopper (45) and the inner wall of the tank body (41), and the gap close to the sewage discharge valve (51) is smaller than the gap far from the sewage discharge valve (51).

7. A dual water pump switching device for a filter press according to claim 1, characterized in that: The tank body (41) is provided with a vent pipe (46) at a position away from the ground, the vent pipe (46) is higher than the water outlet (43), and the vent pipe (46) connects the inside of the tank body with the outside; a pressure relief valve (461) is provided in the vent pipe (46), and the air in the tank body (41) flows out of the tank body through the pressure relief valve (461).

8. A dual water pump switching device for a filter press according to claim 1, characterized in that: The water supply pipeline (2) is provided with a group of alarm devices (7), and the alarm devices (7) are located between the connecting pipeline (6) and the filter press (1); each group of alarm devices (7) comprises two buzzer alarms (74) arranged in parallel, a rotating wheel (71), a connecting rod (72) and a group of weights (73) arranged opposite to each other; the rotating wheel (71) is arranged parallel to the axis of the water supply pipeline (2), and the water flow in the water supply pipeline (2) drives the rotating wheel (71) to rotate; the rotating wheel (71) is coaxial with the connecting pipeline (6) and the filter press (1); A connecting rod (72) is fixedly provided, and the connecting rod (72) is upwardly penetrated through the wall of the water supply pipeline (2); the weight (73) is connected to the end of the connecting rod (72) away from the rotating wheel (71), and the weight (73) can be tilted in the direction of the axis of the connecting rod (72) and swing up and down; the buzzer alarm (74) is fixedly provided on the outer wall of the water supply pipeline (2) near the position of the weight (73), and when the weight (73) abuts against the buzzer alarm (74), the buzzer alarm (74) sounds an alarm.

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