JP2007168938A - Adjusting method for elevator load weighing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an adjusting method for an elevator load weighing device capable of improving work efficiency and reducing cost. <P>SOLUTION: After a car 7 is connected to a pit floor face 14 via an adjustment load cell 15a to fix the car 7, braking force of a brake 3 is released. Tractive force ΔP for pulling the car 7 upwardly by the weight in a counterweight 8 side is measured beforehand by the adjustment load cell 15a. During adjustment of the load weighing device, after the car 7 is fixed to the pit floor face 14 by a connection chain 16, braking force of the brake 3 is released, so as to apply the tractive force ΔP to a load cell 10 of the load weighing device 12. Based on an output value of the load cell 10 at that time, a gain coefficient G and an offset value O of the load cell 10 are calculated and stored in an output characteristic storing part 11a of the load weighing device 12. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method for adjusting an elevator scale device, and more particularly, to a method for adjusting a scale device in a so-called traction rope elevator.

  The elevator weighing device includes a load cell that outputs a value corresponding to the load of the car, stores output characteristics of the load cell, and calculates the load of the car from the output value of the load cell. However, the output characteristics of the load cell may change due to secular change or the like, and it is necessary to appropriately adjust the scale device in order to maintain the performance of the scale device. Here, the adjustment of the weighing apparatus applies a predetermined load to the load cell, reads the output value of the load cell at that time, measures the output characteristic of the load cell, and stores the output characteristic in the weighing apparatus. Is.

  Conventionally, loading test weights in a car as a means for applying a load to the load cell has been performed, but this method requires a great deal of time for loading and unloading heavy test weights into the car. For example, techniques described in Patent Documents 1 and 2 have been proposed.

  The technique described in Patent Document 1 fixes the car by connecting the car and the pit floor via an adjustment load cell, and monitors the output of the adjustment load cell with the hoist motor of the hoisting machine. Is pulled upward and a predetermined load is applied to the load cell of the scale device.

In addition, the technique described in Patent Document 2 fixes the car to the guide rail in the middle of the lifting process so that the main weight of the main rope from the hoist to the car and the main rope from the hoist to the counterweight are equal. After that, the braking force of the brake is released, and the car is pulled upward by the counterweight to load the load cell. Since the weight of the counterweight is set to be the same weight as whether a predetermined balance load is loaded, a load similar to that when the balance load is loaded on the car after releasing the braking force is applied to the load cell. Will be loaded.
JP 2005-145620 A JP 2004-99303 A

  However, in the technique described in Patent Document 1, in order to measure the load applied to the load cell by the hoisting machine, the adjustment load cell must be carried into and out of the pit every time the scale device is adjusted. Therefore, the transportation becomes complicated. In addition, the adjustment load cell is expensive, and it is necessary to calibrate periodically in order to maintain the measurement accuracy, which is disadvantageous in terms of cost.

  Further, in the technique described in Patent Document 2, since the output characteristics of the load cell are calculated based on a preset balance load, the weight of the main rope from the hoisting machine to the car is balanced with the hoisting machine. It is necessary to fix the car to the guide rail in the middle of the up and down stroke so that the main weight of the main rope is balanced, but this work is very dangerous because it is a high place work without securing a scaffold. Not right.

  In view of the above problems, the present invention has an object to provide a method for adjusting a weighing apparatus that reduces costs caused by using special devices such as test weights and load cells for adjustment, and improves workability. Yes.

  According to the first aspect of the present invention, a main rope is wound around a hoisting machine having a brake for stopping a car, the car is suspended on one side of the main rope, and a counterweight is hung on the other side. A method of adjusting a load cell that generates an output in accordance with a load of a car and a weighing device that includes a control unit that performs predetermined control based on an output value from the load cell in an elevator that is lowered, Separately, an adjustment load cell is prepared. With the brake stopping the car, the car is moved up and down by connecting the car and the building frame with the first connecting member interposing the adjustment load cell. Preliminary measurement in which the braking force of the brake is released and the traction force that pulls the car upward due to the weight of the counterweight is measured in advance with the load cell for adjustment after being fixed at a predetermined position at the lower end of the road And an adjustment step for adjusting the scale device based on the traction force measured in the preliminary measurement step, and the adjustment step further includes an output value of the load cell in a state where the car is stopped with no load. In the state where the first reading process for reading the car and the brake is stopping the car, the car and the building frame are connected by the second connecting member to fix the car at the predetermined position of the hoistway, and the load cell. A second reading step for reading the output value of the vehicle, and after the second reading step, by releasing the braking force of the brake, the cage is pulled upward by the traction force to load the load cell, and the load cell The output characteristic of the load cell is obtained based on the output value of the load cell and the traction force in the third reading step for reading the output value of the load cell and the first to third reading steps, and the output characteristic is stored in the control unit A write step of, is characterized in that it consists of.

  Here, the output characteristic is, for example, a gain coefficient and an offset value of a load cell, as described in claim 2, wherein the output value of the load cell in the first reading step is the offset value, and the first The gain coefficient is calculated based on the difference between the output value of the load cell in the second reading step and the output value of the load cell in the third reading step and the traction force, and the first connecting member and the second connecting member For example, as described in claim 3, the lower part of the car is connected to the pit floor surface.

  Therefore, in at least the invention described in claim 1, the weight of the counterweight is used in advance by releasing the braking force of the brake after connecting the car and the building frame with the second connecting member. Since the car is pulled upward with the measured traction force and a load is applied to the load cell, a special device is not required during the adjustment step by measuring the traction force in the preliminary measurement step. In addition, since the car is fixed to the building frame near the lower end of the hoistway, the worker can work safely in the pit.

  Further, as described in claim 4, it is desirable to perform the work of the preliminary measurement process at the time of initial adjustment of the scale device in order to make the adjustment work of the scale device after the initial adjustment easier.

  Here, the initial adjustment means that the output characteristic of the load cell is stored in the control unit when the elevator is installed and is initially set.

  According to the first aspect of the present invention, after the traction force is measured, a special device is not required, and the worker can work safely, thereby improving workability and reducing costs. is there.

  FIG. 1 is a schematic diagram showing the configuration of an elevator to which a specific embodiment of the present invention is applied.

  The elevator is a so-called traction rope elevator, and as shown in FIG. 1, the hoisting machine 1 includes a hoisting motor 2, a brake 3, a drive sheave 4, and a drive shaft 9. That is, the main rope 6 is wound around the driving sheave 4 and the deflecting wheel 5 disposed in the vicinity of the driving sheave 4, and the car 7 is suspended at one end of the main rope 6 and the weight 8 is suspended at the other end. It has been. Further, the power of the hoisting motor 2 is transmitted to the driving sheave 4 by the driving shaft 9 to raise and lower the car 7 and the counterweight 8, and the brake 3 stops the rotation of the driving shaft 9 with the braking force. And stop the counterweight 8.

  Here, since the weight of the counterweight 8 is set to be the same as that of the car 7 when a predetermined load is loaded on the car 7, the weight of the counterweight 8 side is more than the weight of the car 7 side. Is also heavy. Therefore, in a state where the car 7 is not loaded and is restrained by the braking force of the brake 3, the drive shaft 9 rotates toward the counterweight 8 and the car 7 moves upward. 3 will be stopped.

  A load cell 10 is interposed between the main rope 6 and the car 7, and a load loaded on the car 7 is loaded on the load cell 10. The load cell 10 generates a voltage output substantially proportional to the load of the car 7 and the output is taken into the scale control unit 11. The load cell 10 and the scale control unit 11 constitute a scale device 12. ing.

  FIG. 2 is a graph showing output characteristics of the load cell.

  More specifically, the output voltage of the load cell 10 increases along the output characteristic line a as shown in FIG. 2 as the load applied to the load cell 10 increases. Here, the slope of the output characteristic line a is the gain coefficient G, and the output voltage Vo of the load cell 10 in a state where the car 7 is not loaded, that is, only the weight of the car 7 is loaded on the load cell 10 is an offset value. O.

  Accordingly, the scale control unit 11 stores the gain coefficient G and the offset value O in advance as output characteristics of the load cell 10 in the built-in output characteristic storage unit 11a, and is built in the scale control unit 11 based on the output voltage of the load cell 10. The load load calculation unit 11b calculates the load load of the car. Further, the load load calculation unit 11 b outputs the load load of the car 7 calculated as a predetermined control to the main control unit 13. The main control unit 13 controls the operation of the drive motor 2 and the brake 7, and based on the calculated load of the car 7, for example, the car can be started and stopped smoothly, or the car can be loaded. When the load exceeds the maximum load, an alarm is issued and the operation of the car is stopped.

  The gain coefficient G and the offset value O stored in the output characteristic storage unit 11a are stored in advance by the initial adjustment performed at the time of installing the elevator, and the initial adjustment is performed as follows. Yes.

  3 and 4 show the initial adjustment method of the weighing apparatus shown in FIG. 1, FIG. 3 is a flowchart showing the initial adjustment procedure of the weighing apparatus, and FIG. 4 is a schematic diagram showing the elevator during the initial adjustment of the weighing apparatus. is there.

  As shown in FIG. 3, the car 7 is stopped with no load (S1), and the output voltage Vo of the load cell 10 in that state is read (S2).

  Next, as shown in FIG. 4, the lower part of the car 7 and the pit floor 14 which is the building frame are connected by a connecting chain 15 which is a first connecting member having an adjustment load cell 15 a interposed therebetween. The car 7 is fixed to the pit floor 14 at a predetermined position near the lower end of the hoistway so as to restrict the movement to the pit (S3). Here, as a method of connecting the lower part of the car 7 and the pit floor 14 and the connecting chain 15, for example, eyebolts are respectively screwed into the lower part of the car 7 and the pit floor 14 and both ends of the connecting chain 15 are respectively connected. A hook is attached, and the eyebolt and the hook may be engaged with each other. Further, when the car 7 and the pit floor 14 are connected, a tension applying means such as a chain block is interposed in the connecting chain 15 so that the connecting chain 15 and the main rope 6 have substantially equal tension. Tension shall be applied.

  Further, the output voltage V1 of the load cell 10 in a state where the car 7 is fixed to the pit floor 14 is read, and the load P1 applied to the adjustment load cell 15a is measured (S4, S5). The adjustment load cell 15a is calibrated in advance.

  Next, the braking force of the brake 3 is released (S6), the output voltage V2 of the load cell 10 after releasing the braking force is read, and the load P2 loaded on the adjustment load cell 15a is measured (S7, S8).

  Since the brake 3 has stopped the car 7 from being pulled upward due to the weight on the counterweight 8 side, the car 7 is lifted by the weight on the counterweight 8 side when the braking force of the brake 3 is released. And the upward movement of the car 7 is restricted by the connecting chain 16. Therefore, the load is similarly applied to the load cell 10 and the adjustment load cell 16a by the traction force that pulls the car 7 upward by releasing the braking force of the brake 3.

  Next, the offset value O and gain coefficient G of the load cell 10 are obtained (S9, S10), and the obtained offset value O and gain coefficient G are written and stored in the output characteristic storage unit 11a (S11).

As shown in FIG. 2, the tractive force ΔP with which the car 3 is pulled upward by releasing the braking force of the brake 3 in step S6 is:
ΔP = P2−P1
The change ΔV in the output voltage of the load cell 10 due to the traction force ΔP being
ΔV = V2−V1
Is required.

Therefore, the gain coefficient G of the load cell 10 is
G = ΔV / ΔP
Is calculated by

  Further, the output voltage Vo becomes the offset value O of the load cell 10.

  By storing the gain coefficient G and the offset value O obtained as described above in the output characteristic storage unit 11a, the load load calculating unit 11b calculates the car load based on the gain coefficient G and the offset value O. It is.

  The scale device 12 is initially adjusted as described above, but the load coefficient of the car 7 calculated by the load calculation unit 11b is changed as the gain coefficient G and the offset value O of the load cell 10 change due to secular change or the like. Since an error may occur and, for example, a shock may occur during the start and stop of the car, causing problems such as deterioration in ride comfort, it is necessary to adjust the scale device 12 appropriately.

  5 and 6 show a method for adjusting the scale device shown in FIG. 1 as a preferred embodiment of the present invention, FIG. 5 is a flowchart showing the adjustment procedure, and FIG. 6 shows an elevator that is adjusting the scale device. FIG.

  As shown in FIG. 5, the adjustment of the scale device 12 is performed in substantially the same procedure as the initial adjustment. However, since the traction force ΔP is measured in advance as a preliminary measurement step at the time of the initial adjustment, there is no need to use the adjustment load cell 15a. Therefore, as shown in FIG. 6, unlike the initial adjustment, the adjustment of the weighing device 12 is different from the initial adjustment in that a connection chain 16 as a second connection member that does not interpose an adjustment load cell is used to connect the car 7 and the pit floor 14. Is carried out as an adjustment step as follows.

  As shown in FIG. 5, first, as the first reading process, the output voltage Vo of the load cell 10 is read in the same manner as in the steps S1 and S2 at the time of initial adjustment (S21, S22).

  Next, as shown in FIG. 6, as a second reading process, the lower part of the car 7 and the pit floor surface 14 are connected by the connecting chain 16, so that the car 7 is positioned at a predetermined position similar to that at the time of initial adjustment. (S23), and the output voltage V1 of the load cell 10 in that state is read (S24). The car 7 and the pit floor 14 are connected in the same manner as in step S3 at the time of initial adjustment, but differs from step S3 in that no adjustment load cell is interposed in the connection chain 16.

  Next, as a third reading step, the braking force of the brake 3 is released and the output voltage V2 of the load cell after releasing the braking force is read (S25, S26).

  Next, the offset value O and the gain coefficient G of the load cell 10 are obtained in the same manner as the steps S9 and S10 at the time of initial adjustment using the traction force ΔP measured at the time of initial adjustment as the writing step (S27, S28). The gain coefficient G is written and stored in the output characteristic storage unit 11a, and the offset value O and the gain coefficient G stored in the output characteristic storage unit 11a are updated to the current one (S29).

  Therefore, by adjusting the scale device 12 as described above, the load load calculating unit 11b calculates the load load of the car 7 based on the offset value O and the gain coefficient G of the load cell 10 at the present time.

  Further, when the balance device 12 needs to be further adjusted after the balance device 12 is adjusted, the scale device 12 is similarly adjusted.

  Therefore, according to the adjustment method of the scale device 12 as described above, the braking force of the brake 3 is released in a state where the car 7 and the pit floor surface 14 are connected, and the traction force ΔP is utilized using the weight on the counterweight 8 side. Therefore, there is an advantage that the traction force ΔP is measured in advance, so that a special device is not required when adjusting the weighing device 12, and the adjustment of the weighing device 12 is facilitated and the cost can be reduced.

  Further, since the load is applied to the load cell 10 using the weight on the counterweight side, there is a merit that the reproducibility of the load condition on the load cell 10 is good.

  Furthermore, since the car 7 is connected to the pit floor 14 at the lower end of the hoistway, the connecting work can be safely performed in the pit.

  In this embodiment, the connection chains 15 and 16 are used as the first and second connection members. However, instead of the connection chains 15 and 16, a connection rope, a connection rod, or the like may be used.

Schematic which shows the structure of the elevator with which suitable embodiment of this invention is applied. The graph which shows the output characteristic of the load cell in FIG. The flowchart which shows the initial adjustment procedure of the balance apparatus shown in FIG. Schematic which shows the elevator in initial stage adjustment of the scale apparatus shown in FIG. The flowchart which shows the adjustment procedure of the balance apparatus shown in FIG. 1 as suitable embodiment of this invention. It is the schematic which shows the elevator which is adjusting the balance apparatus shown in FIG. 1 as suitable embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Hoisting machine 3 ... Brake 6 ... Main rope 7 ... Car 8 ... Balance weight 10 ... Load cell 11 ... Scale control part 12 ... Weighing device 14 ... Pit floor surface (building frame)
15 ... Connection chain (first connection member)
15a ... Load cell for adjustment 16 ... Connection chain (second connection member)

Claims (4)

In an elevator in which a main rope is wound around a hoisting machine equipped with a brake that stops the car, a car is suspended on one side of the main rope, and a counterweight is suspended on the other side. A method of adjusting a load cell that generates an output in accordance with a loaded load and a scale device including a control unit that performs predetermined control based on an output value from the load cell,
A load cell for adjustment is prepared separately from the above load cell, and the car and the building frame are connected to each other by the first connecting member having the load cell for adjustment interposed in the middle with the brake stopping the car. A pre-measurement step in which the braking force of the brake is released and the traction force by which the car is pulled upward by the weight of the counterweight is measured in advance with an adjustment load cell.
An adjustment process for adjusting the scale device based on the traction force measured in the preliminary measurement process;
Including
The adjustment step comprises the following steps (1) to (4): A method for adjusting an elevator scale device, characterized in that:
(1) A first reading step of reading the output value of the load cell in a state where the car is stopped with no load.
(2) In a state where the car is stopping the car, the car and the building frame are connected by the second connecting member, the car is fixed at the predetermined position of the hoistway, and the output value of the load cell is read. 2 reading step.
(3) After the second reading step, the braking force of the brake is released to pull the car upward with the traction force to load the load cell, and to read the output value of the load cell. Process.
(4) A writing step of obtaining an output characteristic of the load cell based on the output value of the load cell and the traction force in the first to third reading processes and storing the output characteristic in the control unit.   The output characteristic is a gain coefficient and an offset value of the load cell. The output value of the load cell in the first reading step is set as the offset value, and the output value of the load cell in the second reading step and the third value 2. The method of adjusting an elevator scale device according to claim 1, wherein the gain coefficient is calculated based on a difference with an output value of a load cell in the reading step and the traction force.   The method of adjusting an elevator scale device according to claim 1 or 2, wherein the first connecting member and the second connecting member connect the lower part of the car and the pit floor surface. The method of adjusting an elevator scale device according to any one of claims 1 to 3, wherein the preliminary measurement step is performed at the time of initial adjustment of the scale device.

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