JP7692800B2 - Hoisting machine shaft fixing jig - Google Patents

Description

This disclosure relates to a shaft fixing jig for an elevator hoist.

During elevator maintenance and inspection, the backlash of each shaft gear on the hoist is measured. To measure backlash, it is necessary to fix the shaft of the gear that meshes with the gear being measured so that it does not move. However, in conventional backlash measurements, there is no dedicated shaft fixing jig, and a method is used in which a fixed part such as a corner of the hoist frame is used as a fulcrum, and a metal rod made of brass, iron, etc. is pressed against the side of the gear of the fixed shaft to fix the shaft so that it does not move.

Patent document 1 describes a backlash measuring device for elevator drive reducers.

Japanese Unexamined Patent Publication No. 7-172727

The backlash measuring device described in Patent Document 1 is equipped with a rotary encoder on the outer periphery of the sheave, and measures the rotational displacement of the sheave that reverses due to an imbalance between the car and the counterweight that occurs when passengers get on and off, but does not directly measure the gear backlash. Also, if the hoist has multiple axles, it is not possible to measure the backlash for each axle.

Conventional backlash measurements require the operator to hold the rod with one hand while fixing the shaft. This means that the force applied to the rod can change depending on the operator's body movements during measurement, which can cause the gear to move, making the measurement time-consuming. In particular, if the gear diameter of the fixed shaft is small and there is no hoisting machine frame facing the side of the gear, the rod must be inserted at an angle, which means fixing the shaft takes time and there is a risk of not being able to measure accurately.

The objective of this disclosure is to provide a shaft fixing jig for a hoist that can easily fix the fixed shaft when measuring the backlash of each shaft gear of the hoist.

The shaft fixing jig for a hoisting machine according to the present disclosure is characterized by having a rod-shaped main body, a fulcrum recess provided in the middle of the main body and engaging with the frame of the hoisting machine, an application point end at one end of the main body that abuts against the gear side of the fixed shaft, and a protruding screw that engages with a nut provided at the other end of the main body, changes the amount of protrusion of the tip, and abuts against a fixing part around the fixed shaft at a force point.

According to the shaft fixing jig of the hoisting machine disclosed herein, the main body is inserted between the hoisting machine frame and the gear side of the fixed shaft, and the amount of protrusion of the protruding screw is adjusted, so that the shaft fixing jig can be fixed while the fixed shaft is fixed, eliminating the need to hold the shaft fixing jig with one hand and allowing backlash to be easily measured.

FIG. FIG. 2 is a top view of the hoist with the upper cover removed. 1A and 1B are diagrams showing a shaft fixing jig according to an embodiment, in which FIG. 1A to 1C are diagrams illustrating a method for fixing a shaft using a shaft fixing jig according to an embodiment. 13A to 13C are diagrams illustrating other directions in which the shaft is fixed using the shaft fixing jig of the embodiment.

Embodiments of the present disclosure will be described in detail below with reference to the drawings. In the following description, specific shapes, materials, directions, values, etc. are merely examples to facilitate understanding of the present disclosure, and may be modified as appropriate according to the application, purpose, specifications, etc. In addition, it is anticipated from the beginning that the components of the embodiments and modified examples described below will be selectively combined.

First, the configuration of the hoist will be explained with reference to Figures 1 and 2. Figure 1 shows the exterior of an elevator hoist 1, and Figure 2 shows the hoist 1 from above with the top cover 2 removed. The hoist 1 is a device for raising and lowering the elevator car, and is installed on the ceiling of the elevator shaft or in the pit on the lowest floor.

The hoist 1 has a motor 4 (see Figure 2) that generates power, and multiple reduction gear shafts that transmit the rotation from the motor 4 to the sheave 5. A wire rope is wound around the sheave 5, and the elevator cab and a weight are suspended from both ends of the wire rope. The sheave 5 rotates in conjunction with the rotation of the motor 4, raising and lowering the elevator cab.

The hoist 1 has a frame consisting of an upper cover 2 and a bottom frame 3. The upper cover 2 of the hoist 1 is removable. Inspection of the hoist 1 is performed in the state shown in Figure 2 with the upper cover 2 removed.

The motor 4 and sheave 5 are located at the rear of the hoist 1. Four shafts are installed in the left-right direction on the bottom frame 3, which is the frame of the hoist 1. Each of the four shafts is fixed to the bottom frame 3 by a bearing so that it can rotate freely around its axis.

In the hoist 1 in Figure 2, from the right, a first shaft 6, a second shaft 7, a third shaft 8, and a fourth shaft 9 are arranged. The axial direction of each shaft is arranged in parallel. The first shaft 6 can rotate together with the shaft of the motor 4. The rotation of the motor 4 causes the first shaft 6 to rotate, which is transmitted in turn to the adjacent shaft, causing the sheave 5 connected to the fourth shaft 9 to rotate. Note that the number of shafts is just an example and is not limited to four.

As shown in FIG. 2, one gear is connected to each of the first shaft 6 and the fourth shaft 9. Two gears, one large and one small, are connected to each of the second shaft 7 and the third shaft 8 in the axial direction. All of the gears on the first shaft 6 to the fourth shaft 9 are formed as helical gears inclined obliquely to the axial direction. Helical gears are strong and quiet, making them ideal for hoists. However, the gears do not necessarily have to be helical gears, and may be formed as spur gears.

Each of the first shaft 6 to the fourth shaft 9 has a bearing at one end of the shaft and at the middle or other end of the shaft, and the bearings are fixed to the bottom frame 3 of the hoist 1.

The first shaft 6 is supported by a bearing 6a provided at one end of the shaft and a bearing 6b provided in the middle of the shaft, in front of the motor 4. Bearings 6a and 6b are fixed to the end of the bottom frame 3. A gear 6d is provided on the first shaft 6 between bearings 6a and 6b, closer to bearing 6b.

The second shaft 7 is supported by bearings 7a and 7b provided at one end and the other end of the shaft. The second shaft 7 is provided with a small diameter gear 7c at one axial end and a large diameter gear 7d at the other axial end. The gear 7d of the second shaft 7 is arranged to mesh with the gear 6d of the first shaft 6.

The third shaft 8 is supported by bearings 8a and 8b provided at one and the other ends of the shaft. The third shaft 8 is provided with a large-diameter gear 8c at one axial end and a small-diameter gear 8d at the other axial end. The gear 8c of the third shaft 8 is arranged to mesh with the gear 7c of the second shaft 7.

The fourth shaft 9 is supported by a bearing 9a provided at one end of the shaft and a bearing 9b provided in the middle of the shaft, in front of the sheave 5. A gear 9d is provided on the fourth shaft 9 near the bearing 9b. The gear 9d of the fourth shaft 9 is arranged to mesh with the gear 8d of the third shaft 8.

In the hoist 1, the rotation of the motor 4 is input as the rotation of the first shaft 6, and the rotation of the gear 6d of the first shaft 6 is transmitted to the gear 7d of the second shaft 7. The rotation is also transmitted to the third shaft 8 and the fourth shaft 9 via their respective meshing gears, and finally to the fourth shaft 9. The rotational motion of the fourth shaft 9 rotates the sheave 5, which winds up the wire rope and raises and lowers the elevator car.

Next, we will explain how to measure gear backlash. In the following explanation, when two gears mesh with each other, the shaft that transmits the rotation may be called the input shaft, and the shaft that receives the rotation may be called the output shaft.

Backlash is measured by fixing the output shaft, moving the input shaft by hand, and measuring the displacement with a measuring device such as a dial gauge. Therefore, the output shaft is the fixed shaft. The shaft is fixed by placing the middle of a metal rod against the corner of the bottom frame 3 of the hoist as a fulcrum, and pressing the tip of the rod against the side of the gear of the fixed shaft.

When measuring the backlash of the gear 7c of the second shaft 7 of the hoist 1 in Figure 2, with the third shaft 8 as the output shaft and the second shaft 7 as the input shaft, the third shaft 8 is fixed by pressing a metal rod against the side of the gear facing the bearing 8a of the gear 8c of the third shaft 8, using a corner of the bottom frame 3 of the hoist 1 as a fulcrum. The same procedure is carried out when fixing the other shafts of the hoist 1.

In the conventional shaft fixing method, the fixing rod is pressed with one hand while measuring, making accurate measurement difficult. In particular, in the case of the hoist 1 in FIG. 2, it is difficult to measure the backlash of the first shaft 6. The reason for this is that when measuring the backlash of the first shaft 6, the second shaft 7 needs to be fixed, but the diameter of the gear 7c of the second shaft 7 is small, so the bottom frame 3 does not face the gear side of the gear 7c. Therefore, to fix the second shaft 7, it is necessary to place the middle part of the rod against the corner of the bottom frame 3 diagonally forward of the gear 7c and insert the rod diagonally toward the gear side of the gear 7c. Since the rod inserted diagonally is held down with one hand while measuring the backlash of the first shaft 6, the shaft is not fixed stably, which takes time and may result in inaccurate measurement.

The shaft fixing jig 30 of this embodiment solves the above problem.

Next, the shaft fixing jig 30 of this embodiment will be described. Figure 3 shows the shaft fixing jig 30 of this embodiment, with (a) being a front view and (b) being a side view. The shaft fixing jig 30 has a rod-shaped main body 31. As described below, the main body 31 is preferably made of a metal that is difficult to deform because a force is applied to fix the shaft. In addition, because a force is also applied to the side of the gear, brass, which has moderate ductility, is preferable to prevent damage to the gear.

The main body 31 has a recess (fulcrum recess 32) in the middle of the rod in the longitudinal direction. As described below, the fulcrum recess 32 is placed against the frame of the hoist 1 to form a fulcrum for the shaft fixing jig 30.

One end of the main body 31 in the longitudinal direction has a load end 33 for contacting the gear side of the fixed shaft. The load end 33 is brought into contact with the gear side of the fixed shaft and presses the gear side to fix the shaft.

A nut 34 is provided at the other end in the longitudinal direction of the main body 31. A protruding screw 35 is engaged with the nut 34 of the main body 31, and is configured so that the amount of protrusion of the tip can be changed.

The nut 34 is inserted into a through hole 36 provided at the other end of the main body 31, and its side is supported by a support shaft 37. The nut 34 is configured so that the angle can be adjusted with respect to the main body 31, centered on the support shaft 37.

By configuring the angle of the nut 34 to be adjustable, the tip of the protruding screw 35 can be brought into contact with the fixed part perpendicularly, as described below, and the shaft fixing jig 30 can be fixed with a strong force. Note that the angle adjustment function of the nut 34 is not essential. The nut 34 may also be configured with a screw hole that penetrates the main body 31.

One end of the protruding screw 35 protrudes from the nut 34. A rotating handle 38 is provided at the other end of the protruding screw 35. By turning the rotating handle 38, the amount of tightening of the protruding screw 35 into the nut 34 can be changed. Note that the rotating handle 38 is just one example, and for example, a hexagonal head may be provided on the protruding screw 35, and the amount of tightening of the nut 34 may be adjusted by rotating the head.

The main body 31 has a first side 39 and an opposing second side 40. The first side 39 is the surface from which the protruding screw 35 protrudes. As described below, when using the shaft fixing jig 30, the first side 39 is positioned toward the gear side of the fixed shaft.

The second side surface 40 of the main body portion 31 is provided with a fulcrum recess 32. The second side surface 40 has an inclined portion 41 toward the application point end portion 33 of the main body portion 31, and the thickness of the main body portion 31 is reduced. This is to allow the shaft fixing jig 30 to be inserted even if the front gap of the gear side surface of the fixed shaft is small.

The tip of the first side surface 39 may have a protective sheet 42. The protective sheet 42 is preferably made of a resin sheet such as silicone. When fixing the shaft, the load point end portion 33 of the main body portion 31 is pressed against the gear side surface of the fixed shaft, so the protective sheet 42 is provided so as not to damage the gear side surface.

Next, a method for fixing a shaft using the shaft fixing jig 30 of this embodiment will be described with reference to Figure 4. Figure 4 shows a partial cross section taken along line X-X in Figure 2, and shows the arrangement of the shaft fixing jig 30 when measuring the backlash of the second shaft 7 with the third shaft 8 of the hoist 1 as the fixed shaft.

As shown in FIG. 4, insert the main body 31 of the shaft fixing jig 30 between the bottom frame 3 of the hoist 1 and the side of the gear 8c of the third shaft 8.

The third shaft 8 is fixed as follows: The load point end 33 at the tip of the shaft fixing jig 30 is inserted between the bottom frame 3 and the side of the gear 8c of the third shaft 8, and the fulcrum recess 32 on the second side 40 of the main body 31 is positioned so that it abuts the corner (point A) of the bottom frame 3.

Next, in this state, tilt the main body 31 so that the load point end 33 touches the side (point C) of the gear 8c of the fixed shaft.

Next, turn the rotating handle 38 of the protruding screw 35 to adjust the amount of protrusion so that the tip of the protruding screw 35 abuts against the side of the gear 8c of the fixed shaft. The tip of the protruding screw 35 presses against point B on the side of the gear 8c, and as a reaction, the tip of the main body 31 receives a force in the direction of the arrow Y in the figure.

When a force acts in the direction of arrow Y at point B, a force acts on the side of the gear in the direction of arrow Z in the figure, with point A as the fulcrum and point C as the point of application, due to the principle of leverage. The third shaft 8 is fixed in place by the force acting in the direction of arrow Z at point C.

By pressing point B with sufficient force using the protruding screw 35, the shaft fixing jig 30 can be fixed at three points: fulcrum A, force point B, and action point C. Therefore, there is no need to hold the shaft fixing jig 30 by hand.

The shaft fixing jig 30 of this embodiment allows the user to keep both hands free, so the user can measure the backlash stably without losing their balance when measuring the backlash.

The backlash is measured by manually moving the gear 7c of the second shaft 7, which is the input shaft, using a dial gauge to read the displacement. How to use a dial gauge is well known, so details will be omitted.

The shaft fixing jig 30 of this embodiment is configured so that the angle of the nut 34 is adjusted around the support shaft 37. When the tip of the protruding screw 35 abuts against the gear side of the fixed shaft, the angle of the nut 34 is automatically adjusted, and the tip of the protruding screw 35 can be abutted perpendicularly against the gear side of the fixed shaft. The tip of the protruding screw 35 can press the gear side of the fixed shaft perpendicularly, allowing a large force to be applied.

Next, referring to FIG. 5, another method of fixing a shaft using the shaft fixing jig 30 of this embodiment will be described. The case where the fixed shaft in the hoist 1 of FIG. 2 is the second shaft 7 and the backlash of the first shaft 6 is measured will be described.

Since the diameter of the gear 7c of the second shaft 7 is small, there is no bottom frame 3 in a position facing the side of the gear 7c. Therefore, it is necessary to select a fixed surface to which force is applied as the fulcrum and force point of the lever. In this case, as shown in Figure 5, the bottom frame 3 located diagonally forward of the second shaft 7 is used as the fulcrum, and the side of the gear 8c adjacent to the second shaft 7, which is the fixed shaft, is used as the fixed surface.

Specifically, the fulcrum recess 32 of the main body 31 is placed against the corner (point A) of the bottom frame 3 diagonally in front of the second shaft 7, and the load end 33 is inserted at an angle so that it is placed against the gear side (point C) of the gear 7c of the second shaft 7. At this time, the main body 31 is inserted at an angle so that the load end 33 faces downward and the protruding screw 35 at the other end faces upward. Then, with the side of the gear 8c of the third shaft 8 as the fixed surface, the tip of the protruding screw 35 is placed against the side of the gear 8c (point B).

In this state, the rotation handle 38 of the protruding screw 35 is turned so that the tip of the protruding screw 35 abuts the side of the gear 8c (point B) as a force point to adjust the amount of protrusion. As a result, the tip of the protruding screw 35 presses against point B on the side of the gear 8c, and as a reaction, one end of the main body 31 receives a force in a direction away from the side of the gear 8c. In this way, by using the principle of leverage, the second shaft 7 can be fixed by pressing the side of the gear 7c with point A as the fulcrum and point C as the point of application.

In the method shown in Figure 5, the second shaft 7 is fixed by pressing point B with sufficient force using the protruding screw 35, and the shaft fixing jig 30 can be fixed at three points: the bottom frame 3 (point A), the side of the gear 8c of the third shaft 8 (point B), and the side of the gear 7c of the second shaft 7 (point C).

When inserting the jig at an angle like this, it is difficult to fix the shaft using conventional methods, and it is difficult to measure backlash while holding it down with one hand. With the shaft fixing jig 30 of this embodiment, it is possible to perform stable measurements even in such cases.

In this embodiment, the hoist 1 has a helical gear, but it can also be applied to measuring the backlash of the gear of a hoist that has a spur gear.

The present invention is not limited to the above-described embodiment and its variations, and various modifications and improvements are possible within the scope of the claims of this application.

REFERENCE SIGNS LIST 1 hoist, 2 upper cover, 3 bottom frame, 4 motor, 5 sheave, 6 first shaft, 6a, 6b bearing, 6d gear, 7 second shaft, 7a, 7b bearing, 7c, 7d gear, 8 third shaft, 8a, 8b bearing, 8c, 8d gear, 9 fourth shaft, 9a, 9b bearing, 9d gear, 30 shaft fixing jig, 31 main body, 32 fulcrum recess, 33 application point end, 34 nut, 35 protruding screw, 36 through hole, 37 support shaft, 38 rotating handle, 39 first side, 40 second side, 41 inclined surface, 42 protective sheet

Claims (3)

A rod-shaped main body portion is provided,
A fulcrum recess provided in an intermediate portion of the main body and adapted to engage with a frame of a hoist;
a load point end portion which is one end portion of the main body portion and which abuts against a gear side surface of the fixed shaft;
a protruding screw that engages with a nut provided at the other end of the main body and changes the amount of protrusion of the tip thereof to come into force contact with a fixed portion around the fixed shaft;
having
A shaft fixing jig for a hoisting machine. The nut of the main body is inserted into a hole penetrating the main body provided at the other end and is supported from a side surface of the hole so as to be angle adjustable.
A shaft fixing jig for a hoisting machine according to claim 1. The main body portion has a thickness that decreases toward the application point end.
A shaft fixing jig for a hoisting machine according to claim 1 or 2.

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