Roll-on machine

Abstract

To provide a hoist capable of easily performing maintenance and replacing works than before.SOLUTION: A hoist comprises a traction sheave to wind and rewind a rope, a shaft arranged along the rotational axis of the traction sheave and to rotate the traction sheave, and a rotor attached to one end of the shaft and rotating by magnetic force to stator magnetic field. The rotor has a boss part forming a first engaging part and multiple second engaging parts between the shaft and the boss part. The boss part has a cylindrical body into which one end of the shaft is inserted, and a flange part protruding to the inner circumference of the cylindrical body and facing the end face on one end side of the shaft. The inner circumferential surface of the cylindrical body and the outer circumferential surface of the shaft are engaged in the first engaging part. The flange part and the shaft are engaged via a pin by the pin inserted through the flange part and engaged axially to the shaft in each of the second engaging parts.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a hoist. [Background technology]

[0002] Conventionally, elevator hoists have been known, which use an electric motor to rotate a drive sheave to move a car. In recent years, there has been a demand for larger capacity and faster hoists to improve the transport capacity of elevators, while there has also been a demand for lower noise and vibration hoists to improve environmental performance. There is also a demand for smaller and lighter hoists to facilitate elevator installation work.

[0003] To meet the above demands, for example, Patent Document 1 discloses a hoist including a rotating shaft to which a sheave is fixed and a spider that fits onto the tip of the rotating shaft from the outer periphery and fits onto the inner periphery of a rotor core. In the hoist of Patent Document 1, the tip of the rotating shaft is formed with a tip outer periphery for fitting and a fitting convexity that extends axially from the tip. The spider is formed with a convexity fitting portion that fits onto the outer periphery of the convexity and a rear end extension that fits onto the tip outer periphery. According to Patent Document 1, the rigidity of the spider that fits onto the rotating shaft is improved, resulting in a significant effect of suppressing spider deflection, and it is said that noise and vibration during operation can be suppressed without compromising assembly. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 5955563 Summary of the Invention [Problem to be solved by the invention]

[0005] In recent years, from the perspective of building a sustainable society, the ease of maintenance and replacement of a traction machine is becoming increasingly important as one of the performance indicators of a traction machine. For example, it is extremely desirable for a traction machine to be easy to disassemble and assemble in a machine room with limited space, such as on the top floor of a high-rise building.

[0006] On the other hand, for example, in the case of Patent Document 1, when performing maintenance or replacement in the machine room, it is necessary to bring in large hydraulic equipment and the like, and it is also necessary to secure a relatively large work space on-site. This makes it difficult to perform maintenance or replacement of the hoisting machine, and there is room for improvement in that, for example, the elevator may be stopped for a long period of time due to maintenance or replacement.

[0007] The present invention has been made in consideration of the above circumstances, and provides a hoist that allows maintenance and replacement work to be performed more easily than before. [Means for solving the problem]

[0008] A hoist according to one aspect of the present invention includes a drive sheave that winds and unwinds a rope, a shaft arranged along the rotation axis of the drive sheave and rotating the drive sheave, and a rotor attached to one end of the shaft and rotating due to magnetic force generated by the magnetic field of the stator. The rotor has a boss portion that forms a first fitting portion and multiple second fitting portions with the shaft. The boss portion has a cylindrical body into which one end of the shaft is inserted and a flange portion that protrudes from the inner circumference of the cylindrical body and faces the end face of the one end of the shaft. At the first fitting portion, the inner circumferential surface of the cylindrical body and the outer circumferential surface of the shaft are fitted together, and at each second fitting portion, a pin is inserted through the flange portion and fitted axially into the shaft, thereby fitting the flange portion and the shaft together via a pin. One end of the shaft is formed with a first joint surface perpendicular to the rotation axis, and the flange portion is formed with a second joint surface perpendicular to the rotation axis facing the first joint surface. The flange and the shaft are fixed to each other with a fixing bolt at a joint portion where the first joint surface and the second joint surface are in contact with each other. The first fitting portion has a first region provided on the tip side of the shaft and a second region provided axially spaced from the first region, where the inner circumferential surface of the cylindrical body and the outer circumferential surface of the shaft are fitted together. The outer diameter of the shaft is smaller at the corresponding portion of the first region than at the corresponding portion of the second region, and the inner diameter of the cylindrical body is smaller at the corresponding portion of the first region than at the corresponding portion of the second region.

[0011] The pin may have a tapered shape with a diameter decreasing toward the tip end in the fitting direction, and when the second fitting portion is fitted, the pin may be fastened to the shaft by a bolt inserted into the pin. The flange portion may have a threaded hole into which a pull-out screw can be screwed, the pull-out screw pressing one end of the shaft when the rotor and the shaft are disassembled. [Effects of the Invention]

[0012] The hoist of one aspect of the present invention allows maintenance and replacement work to be performed more easily than in the past. [Brief explanation of the drawings]

[0013] [Figure 1] FIG. 2 is a front view of the hoisting machine of the first embodiment. [Figure 2] FIG. 2 is a left side view of the hoisting machine of the first embodiment. [Figure 3] FIG. 2 is an exploded view of the shaft and rotor in FIG. 1. [Figure 4] FIG. 10 is a front view of a hoisting machine according to a second embodiment. [Figure 5] 10 is an enlarged view showing a fitting step of a first fitting portion in the second embodiment. FIG. [Figure 6] FIG. 10 is a front view of a hoisting machine according to a third embodiment. [Figure 7] FIG. 10 is a left side view of the hoisting machine of the third embodiment. [Figure 8] FIG. 10 is a front view of a hoisting machine according to a fourth embodiment. [Figure 9] FIG. 10 is a left side view of a hoisting machine according to a fourth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0014] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the embodiments, in order to make the explanation easier to understand, the structures and elements other than the main parts of the present invention will be explained in a simplified or omitted manner. Furthermore, the same elements will be given the same reference numerals in the drawings. Note that the shapes, dimensions, etc. of the elements shown in the drawings are shown schematically and do not represent the actual shapes, dimensions, etc.

[0015] In the drawings, the direction parallel to the extension direction of the rotation axis AX of the hoisting machine is referred to as the "axial direction." In the following description, the circumferential direction centered on the rotation axis AX is simply referred to as the "circumferential direction," and the radial direction centered on the rotation axis AX is simply referred to as the "radial direction."

[0016] First Embodiment Fig. 1 is a front view of a hoisting machine 1 of the first embodiment, and Fig. 2 is a left side view of the hoisting machine 1 of the first embodiment. The hoisting machine 1 of the first embodiment is applied to a hoisting machine for an elevator, for example.

[0017] The hoist 1 comprises a cylindrical drive sheave 2, a shaft 3, a first bearing stand 4, a second bearing stand 5, a rotor 6, and a stator 7. The drive sheave 2 has a rope winding surface 2a on its outer circumferential surface, and functions to wind up or unwind a rope (not shown) that connects the car and the weight. The shaft 3 passes through the drive sheave 2 in the axial direction and is attached concentrically to the drive sheave 2.

[0018] The first bearing pedestal 4 and the second bearing pedestal 5 are each erected on a mounting pedestal 8. The mounting pedestal 8 is fixed to the floor of the elevator machine room, for example. The first bearing pedestal 4 is disposed on one side (the left side in FIG. 1) of the drive sheave 2 and has a first bearing 4a that receives the shaft 3. The second bearing pedestal 5 is disposed on the other side (the right side in FIG. 1) of the drive sheave 2 and has a second bearing 5a that receives the shaft 3. For the first bearing 4a and the second bearing 5a, for example, a self-aligning roller bearing can be used. As a result, the shaft 3 and the drive sheave 2 are rotatably supported by the first bearing 4a of the first bearing pedestal 4 and the second bearing 5a of the second bearing pedestal 5.

[0019] One end of the shaft 3 penetrates the first bearing stand 4 and protrudes to one side. Hereinafter, the part of the shaft 3 that protrudes to one side beyond the first bearing stand 4 will also be referred to as a cantilever shaft part 10. The rotor 6 and the stator 7 are arranged on one side of the first bearing stand 4. In addition, the second bearing stand 5 is provided with a brake device (not shown) that stops the rotation of the drive sheave 2.

[0020] The rotor 6 has a cylindrical boss 11 fitted onto the cantilever shaft 10 of the shaft 3, and a cylindrical magnetic pole 12 arranged concentrically around the outer periphery of the boss 11. A plurality of magnets 12a are attached to the outer periphery of the magnetic pole 12 so that different magnetic poles are arranged periodically in the circumferential direction. The boss 11 and the magnetic pole 12 are connected in the radial direction by a plurality of support posts 13 arranged in the circumferential direction. In addition, a plurality of ventilation holes 14 are formed between each support post 13 of the rotor 6 in a ring shape in the circumferential direction.

[0021] A cylindrical stator 7 is disposed on the outer periphery of the rotor 6 so as to face the magnetic pole portions 12 of the rotor 6 across an air gap. As shown in FIG. 2, the underside of the stator 7 is fixed to a mounting base 8. A coil (not shown) is wound around the stator 7. By controlling the current in the coils to sequentially switch the magnetic field of the stator 7, an attractive force or a repulsive force is generated in the stator 7 relative to the magnetic field of the rotor 6. This causes the drive sheave 2 to rotate via the shaft 3 to which the rotor 6 is attached.

[0022] Next, the fitting structure of the shaft 3 and the rotor 6 in the first embodiment will be described in detail. Here, the partial cross section of the shaft 3 and the rotor 6 in Fig. 1 is a cross section taken along the line BOCDE in Fig. 2. Also, Fig. 3 is an exploded view of the shaft 3 and the rotor 6 in Fig. 1.

[0023] The cantilever shaft portion 10 of the shaft 3 is cylindrical, and the outer peripheral surface of the cantilever shaft portion 10 forms an outer peripheral fitting surface 10a that fits onto the boss portion 11 of the rotor 6. The outer peripheral fitting surface 10a is concentric with the rotation axis AX of the shaft 3. One end face of the cantilever shaft portion 10 forms a first joint surface 10b. The first joint surface 10b of the cantilever shaft portion 10 is a plane perpendicular to the outer peripheral fitting surface 10a, and is provided with a plurality of pin holes 15 and bolt holes 16 that extend in the axial direction. The pin holes 15 are cylindrical recesses with a bottom. The bolt holes 16 have female threads engraved on the inner circumference into which a fixing bolt 19 can be screwed.

[0024] The pin holes 15 and the bolt holes 16 are arranged at regular intervals in the circumferential direction on a circle concentric with the rotation axis AX. In the first embodiment, four pin holes 15 and four bolt holes 16 are opened in the first joint surface 10b at 90-degree intervals, and the positions of the pin holes 15 and the bolt holes 16 are shifted in phase by 45 degrees.

[0025] The boss portion 11 of the rotor 6 has a cylindrical boss body 11a and an annular flange portion 11b formed on one side of the boss body 11a. The inner diameter of the boss body 11a is dimensioned to provide a tight fit with the outer diameter of the cantilever shaft portion 10, and the inner peripheral surface of the boss body 11a forms an inner peripheral fitting surface 11a1 that fits onto the outer peripheral fitting surface 10a of the cantilever shaft portion 10.

[0026] The flange portion 11b of the boss portion 11 is a flat plate that protrudes toward the inner periphery of the boss body 11a and has a circular opening in the center. The other surface of the flange portion 11b forms a second joint surface 11b1 that faces the first joint surface 10b of the cantilever shaft portion 10. The second joint surface 11b1 of the flange portion 11b is a plane that is perpendicular to the inner periphery fitting surface 11a1 of the boss body 11a.

[0027] Furthermore, a pin hole 17 and a bolt hole 18 are formed in the flange portion 11b at positions corresponding to the pin hole 15 and the bolt hole 16 of the cantilever shaft portion 10, respectively. The pin hole 17 of the flange portion 11b is a circular hole of the same diameter as the pin hole 15 of the cantilever shaft portion 10, and passes through the flange portion 11b. When the shaft 3 and the rotor 6 are assembled, the pin hole 17 of the flange portion 11b is integrated with the pin hole 15 of the cantilever shaft portion 10 and becomes flush with it. The bolt hole 18 of the flange portion 11b is a circular hole through which, for example, a fixing bolt 19 can be inserted.

[0028] The cantilever shaft portion 10 of the shaft 3 is inserted into the boss portion 11 of the rotor 6 from the other side. When the shaft 3 and the rotor 6 are assembled, the outer peripheral fitting surface 10a of the cantilever shaft portion 10 and the inner peripheral fitting surface 11a1 of the boss body 11a are fitted together and come into surface contact with each other, forming a first fitting portion 22.

[0029] The first fitting portion 22 fixes the rotor 6 to the cantilever shaft portion 10 and also functions to suppress the eccentricity of the rotor 6. The specifications of the first fitting portion 22, such as the diameter, length, and interference, can be appropriately set under conditions that allow it to support radial forces acting on the rotor 6 (for example, load due to the mass of the rotor 6, centrifugal force during rotation due to eccentricity, magnetic attraction force, etc.) and to fix the rotor 6 concentrically to the cantilever shaft portion 10 with high precision.

[0030] Furthermore, when the shaft 3 and rotor 6 are assembled, the second joint surface 11b1 of the flange portion 11b faces the first joint surface 10b of the cantilever shaft portion 10. The fixing bolt 19 is inserted through the bolt hole 18 of the flange portion 11b and screwed into the bolt hole 16 of the cantilever shaft portion 10. As a result, the first joint surface 10b and the second joint surface 11b1 are mechanically joined together by the fixing bolt 19, and a joint 24 is formed on a plane intersecting the axial direction.

[0031] Both the first joint surface 10b and the second joint surface 11b1 are perpendicular to the fitting surface of the first fitting portion 22, and the axial position of the rotor 6 is determined by the joining of the first joint surface 10b and the second joint surface 11b1. Furthermore, when the first joint surface 10b and the second joint surface 11b1 are brought into close contact with each other and fastened with the fixing bolt 19, no tilting of the components occurs due to tightening. As described above, the joint portion 24 determines the axial position of the rotor 6 relative to the shaft 3, and also functions to maintain a state in which the rotor 6 is fixed concentrically to the cantilever shaft portion 10 with precision.

[0032] Furthermore, when the shaft 3 and rotor 6 are assembled, pins 26 are fitted into the pin holes 15, 17 of the cantilever shaft portion 10 and the flange portion 11b. As a result, the pins 26 are fitted into the pin holes 15 of the cantilever shaft portion 10 and the pin holes 17 of the flange portion 11b, and a plurality of second fitting portions 28 are formed on a plane intersecting the axial direction.

[0033] The multiple second fitting portions 28 function to transmit torque from the rotor 6 to the shaft 3. The second fitting portions 28 also function to firmly fix the rotor 6 to the cantilever shaft portion 10 against the movement of the rotor 6 in the rotational and radial directions.

[0034] Here, the shape of the pin 26 is cylindrical with dimensions such that the outer diameter is a tight fit with the pin holes 15, 17. An air vent hole 26a is formed in the center of the pin 26, penetrating the pin 26 in the axial direction. The air vent hole 26a of the pin 26 functions to release air remaining at the bottom of the pin hole 15 during assembly to the outside, thereby suppressing an increase in the insertion resistance of the pin 26 due to air pressure. In addition, a female thread 26b is engraved on one side of the inner periphery of the air vent hole 26a, for fastening a jig (not shown) when pulling the pin 26 out of the cantilever shaft portion 10 and the flange portion 11b.

[0035] Furthermore, since the multiple second fitting portions 28 distribute and transmit the torque between the rotor 6 and the shaft 3, the fitting force of the pin 26 required at each second fitting portion 28 decreases as the number of second fitting portions 28 increases. Therefore, according to the first embodiment, the fitting force at each second fitting portion 28 can be kept to a level that allows for easy disassembly and assembly by manual labor of an operator, without the need for large-scale hydraulic equipment.

[0036] As an example, in designing the second fitting portions 28, the specifications such as the dimensions and interference of the pin 26 and pin holes 15, 17 may be determined so that the fitting force of each second fitting portion 28 is such that it can be easily disassembled and assembled by hand. The number of second fitting portions 28 can be calculated by dividing the fitting force per second fitting portion 28 by the total fitting force required to reliably transmit torque in forward and reverse rotations without play, and rounding up the quotient to an integer.

[0037] In the first embodiment, the rotor 6 is supported concentrically on the cantilever shaft portion 10 with high precision by the three elements of the first fitting portion 22, the second fitting portion 28, and the joint portion 24, and the shaft 3 and the rotor 6 are firmly fixed in all directions, including the rotational, radial, and axial directions. The shaft 3 and the rotor 6 can then reliably transmit torque in both forward and reverse directions without any backlash. This reduces vibration and noise from the hoisting machine 1, improves the characteristics of the rotating electric machine, and contributes to making the hoisting machine 1 more compact.

[0038] Next, the assembly and disassembly of the shaft 3 and the rotor 6 in the first embodiment will be described.

[0039] In assembling the shaft 3 and the rotor 6, a worker inserts the cantilever shaft portion 10 of the shaft 3 into the boss portion 11 of the rotor 6 from the other side. The cantilever shaft portion 10 can be inserted into the boss portion 11 manually using, for example, a jig or the like configured to pull the rotor 6 toward the cantilever shaft portion 10 by utilizing the bolt holes 16 of the cantilever shaft portion 10.

[0040] Thereafter, fixing bolts 19 are threaded into bolt holes 16 of the cantilever shaft portion 10 through bolt holes 18 of the flange portion 11b. At this stage, the outer peripheral fitting surface 10a of the cantilever shaft portion 10 and the inner peripheral fitting surface 11a1 of the boss body 11a are fitted together to form a first fitting portion 22. In addition, the first joint surface 10b of the cantilever shaft portion 10 and the second joint surface 11b1 of the flange portion 11b are brought into close contact to form a joint portion 24. The fitting force of the first fitting portion 22 is sufficient to fix the rotor 6 concentrically to the cantilever shaft portion 10 with high precision, so an operator can easily insert the cantilever shaft portion 10 into the boss portion 11 of the rotor 6 by hand.

[0041] Then, a worker inserts pins 26 into the pin holes 15, 17 of the flange portion 11b and the cantilever shaft portion 10. The pins 26 are inserted manually using, for example, a hammer or an insertion jig. This forms multiple second fitting portions 28, firmly fixing the shaft 3 and the rotor 6 together. The fitting force per second fitting portion 28 is small enough to allow the worker to manually insert the pins without requiring large-scale hydraulic equipment. In addition, an air vent hole 26a is formed in the pin 26 in the axial direction, so that the air pressure in the pin hole 15 does not increase insertion resistance. Therefore, the worker can easily manually insert the pins 26 into the pin holes 15, 17.

[0042] On the other hand, when disassembling the shaft 3 and the rotor 6, a worker first uses a removal tool having a jack or the like to remove the pin 26 from the pin holes 15, 17. The pin 26 can be easily removed by screwing the jig onto the internal threads 26b of the pin 26.

[0043] Then, after removing the fixing bolts 19, the rotor 6 is pulled out from the cantilever shaft portion 10, thereby separating the shaft 3 and the rotor 6. For example, when pulling out the rotor 6 from the cantilever shaft portion 10, a worker can insert a jig through the ventilation hole 14, hook the jig onto the end face of the boss body 11a, and separate the jig from the cantilever shaft portion 10 using a screw mechanism or the like. Even in such disassembly work, the worker can manually separate the shaft 3 and the rotor 6 without the need for hydraulic equipment.

[0044] An example of calculating the fitting force in the first embodiment will be specifically described below in comparison with a comparative example. The comparative example is similar to the above-mentioned Patent Document 1 (Japanese Patent No. 5955563), and has a configuration in which torque is transmitted by a mating portion, which is mainly composed of the rear end extension of the spider and the outer periphery of the front end of the rotating shaft. The configuration of the comparative example firmly fixes the rotor to the rotating shaft while holding it with precision by the force pressing the surfaces with the interference of the mating portion (fitting force) and the friction force of the mating portion (fitting friction force). Furthermore, in the configuration of the comparative example, torque is transmitted from the spider, which is integrated with the rotor, to the rotating shaft by the friction torque of the mating portion (also called fitting friction torque).

[0045] The relationships among the fitting force, fitting friction force, fitting friction torque, friction coefficient, and working radius (radius of the fitting portion) in the comparative example are as shown in the following formulas (1) to (4), where F is the fitting friction force, W is the fitting force, μ is the friction coefficient, T is the fitting friction torque, and r is the working radius. F=W×μ…Equation (1) W=F / μ…Equation (2) T=F×r…Equation (3) F=T / r…Equation (4)

[0046] The engagement friction force is the force required for disassembling and assembling the hoist, and the engagement friction torque is the force required for torque transmission. Therefore, the actual values ​​of these parameters can be used to determine the difficulty of disassembling and assembling the hoist.

[0047] For example, in the case of a typical model of a large-capacity, high-speed hoist, the fitting friction force in the configuration of the comparative example is as follows: Note that since the value of the friction coefficient varies depending on the lubrication state, surface roughness, deterioration over time, etc., the minimum friction coefficient μa is used in torque transmission calculations, and the maximum friction coefficient μb is used in disassembly and assembly calculations.

[0048] The calculation conditions for the comparative example are as follows: The hoist requires a fitting friction torque with the same value as the transmission torque Tm. Transmission torque Tm: 45 kN m (design value including safety factor) Friction torque T1 in the comparative example: 45 kN m (value required for torque transmission) Radius of action r1 in the comparative example: 0.2 m Friction coefficient μ: 0.15 (when transmitting torque μa) to 0.40 (when disassembling and assembling μb)

[0049] In the configuration of the comparative example, the fitting friction force F1a required for torque transmission was calculated based on the formula (4), and the result is shown in the following formula (5). F1a=T1 / r1=45 / 0.2=225(kN)...Equation (5)

[0050] Furthermore, in the configuration of the comparative example, the fitting force W1 required for torque transmission was calculated based on equation (2), and the result is shown in the following equation (6). Note that the friction coefficient used is μa=0.15 during torque transmission. W1=F1a / μa=225 / 0.15=1500(kN)...Formula (6)

[0051] Furthermore, in the configuration of the comparative example, the fitting friction force F1b during disassembly and assembly was calculated based on formula (1), and the result is shown in formula (7) below, where the fitting force W1 = 1500 (kN), and the friction coefficient during disassembly and assembly μb = 0.40 is used. F1b=W1×μb=1500×0.4=600(kN) …Equation (7)

[0052] The above-mentioned frictional engagement force F1b during disassembly and assembly is the force required to pull out and insert the rotor when disassembling and assembling the traction machine in the comparative example. In the configuration of the comparative example, the frictional engagement force F1b is 600 kN as shown in Equation (7), making it virtually impossible to disassemble and assemble the traction machine by hand. In other words, in the configuration of the comparative example, the actual disassembly and assembly work of the traction machine requires the preparation in advance of hydraulic equipment capable of generating a force exceeding 600 kN, as well as equipment including jigs and tools corresponding to the hydraulic equipment, and the transport of this equipment into the machine room on the top floor of a high-rise building. However, since it is practically difficult to transport the equipment into the machine room and to secure work space in the machine room, the comparative example has the problem of longer maintenance and replacement times, resulting in prolonged elevator outages.

[0053] Next, the fitting force in the hoisting machine 1 of the first embodiment will be described. The shaft 3 and rotor 6 in the first embodiment have two types of fitting portions: a first fitting portion 22 formed by the fitting of the outer peripheral fitting surface 10a of the cantilever shaft portion 10 with the inner peripheral fitting surface 11a1 of the boss body 11a, and a plurality of second fitting portions 28 formed by pins 26 fitted into the cantilever shaft portion 10 and the flange portion 11b.

[0054] The first fitting portion 22 is a cylindrical interference fit that can be machined and assembled with high precision, and serves to reduce the eccentricity of the rotor 6 relative to the shaft 3 and to fix the rotor 6 to the cantilever shaft portion 10 with high precision. The first fitting portion 22 mainly functions to support the radial force acting on the rotor 6. As described above, the torque transmission between the shaft 3 and the rotor 6 is mainly carried out by the second fitting portion 28, and the first fitting portion 22 is not expected to have a torque transmission function, so the fitting force required by the first fitting portion 22 is significantly reduced.

[0055] For example, in the specifications of a typical model of a large-capacity, high-speed hoist, the radial force acting on the rotor 6 is 100 kN. Since the first fitting portion 22 supports the above radial force, the fitting force W2 required for the first fitting portion 22 is 100 kN. As can be seen, the fitting force of the first fitting portion 22 is much smaller than in the comparative example. Therefore, in the first embodiment, the dimensions of the first fitting portion 22 can be made smaller than in the comparative example, thereby making it possible to reduce the size and weight of the boss portion 11.

[0056] The mating friction force F2b during disassembly and assembly of the first mating portion 22 can be calculated as the product of the mating force W2 and the friction coefficient μ. Therefore, the mating friction force F2b during disassembly and assembly of the first mating portion 22 is 40 kN, which is the product of the mating force W2 = 100 kN and the friction coefficient μb during disassembly and assembly = 0.40.

[0057] Furthermore, in the first embodiment, each second fitting portion 28 is set to a size that can be manually disassembled and assembled, and the plurality of second fitting portions 28 are responsible for torque transmission between the shaft 3 and the rotor 6. As an example, in the first embodiment, the fitting friction force at each second fitting portion 28 and the sum of the fitting friction torque at the plurality of second fitting portions 28 are as follows:

[0058] First, when the mating friction force per location of the second mating portion 28 is set to a value that allows manual disassembly and assembly, the mating force per location of the second mating portion 28 is also determined at the same time. Furthermore, when the second mating portion 28 transmits torque, the tangential force of the torque, with the axial center distance between the second mating portion 28 and the cantilever shaft portion 10 as the acting radius, is transmitted from the mating portion between the pin 26 and the rotor 6 to the mating portion between the pin 26 and the cantilever shaft portion 10. Therefore, in order to reliably transmit torque for forward and reverse rotation without backlash, a total mating force equivalent to the tangential force of the torque is required for each of the mating portions between the pin 26 and the rotor 6 and between the pin 26 and the cantilever shaft portion 10.

[0059] The total mating force of the multiple second mating portions 28 is the sum of the total mating force of the mating portions between the pin 26 and the rotor 6 and the total mating force of the mating portion between the pin 26 and the cantilever shaft portion 10. Typically, the total mating force is the same at the mating portion between the pin 26 and the rotor 6 and at the mating portion between the pin 26 and the cantilever shaft portion 10, so the total mating force of the second mating portions 28 needs to be twice the tangential force of the torque. Furthermore, if the required total mating force is greater than the mating force of a single second mating portion 28, it is necessary to provide a number of second mating portions 28 that can bear the total mating force. Specifically, it is sufficient to provide an integer or more number of second mating portions 28 by dividing the mating force per portion by the total mating force and rounding up the quotient.

[0060] Here, the relationship between the torque tangential force, total mating force, mating force per location, and mating friction force at the second mating portion 28 is as shown in the following equations (8) to (11). Here, R3 is the torque tangential force, T3 is the design value of the transmitted torque, and r3 is the acting radius. Also, W3 is the total mating force of the second mating portion 28, w3 is the mating force per location of the second mating portion 28, and n is the number of second mating portions 28. Also, F3b is the mating friction force, and μb is the friction coefficient during disassembly and assembly. R3=T3 / r3…Equation (8) W3=2×R3…Equation (9) w3=W3 / n=2×R3 / n=2×T3 / r3 / n…Equation (10) F3b=w3×μb=2×T3 / r3 / n×μb…Equation (11)

[0061] In the following, we will assume a case where the number of second fitting portions 28 is four in accordance with the specifications of a typical model of a large-capacity, high-speed hoist. The calculation conditions in this case are as follows: Transmission torque T3: 45 kN m (design value including safety factor) Radius of action r3: 0.16m (r2=0.8×r1=0.8×0.2=0.16) Number of second fitting portions 28 n: 4 Friction coefficient μb: 0.40 (friction coefficient during disassembly and assembly)

[0062] The fitting force w3 per location of the second fitting portion 28 is calculated based on the formula (10) and is shown in the following formula (12). w3=2×T3 / r3 / n=2×45 / 0.16 / 4=141(kN) …Formula (12)

[0063] Furthermore, the result of calculating the fitting friction force F3b of the second fitting portion 28 based on the formula (11) is shown in the following formula (13). F3b=w3×μb=141×0.4=56(kN) …Equation (13)

[0064] As is clear from the above calculation examples, in the first embodiment, the mating friction force F2b of the first mating portion 22 is 40 kN, and the mating friction force F3b per location of the second mating portion 28 is 56 kN. Therefore, in the configuration of the first embodiment, the mating friction force during disassembly and assembly is extremely small compared to the comparative example, and it can be seen that disassembly and assembly of the hoist 1 by hand is fully possible. Therefore, in the configuration of the first embodiment, there is no need to carry large hydraulic equipment, etc. into the machine room during disassembly and assembly, making maintenance and replacement work easy to perform.

[0065] Second Embodiment Fig. 4 is a front view of the hoist 1 of the second embodiment, and Fig. 5 is an enlarged view showing the fitting process of the first fitting portion 22 in the second embodiment. In the following description of each embodiment, redundant description of elements common to the first embodiment will be omitted as appropriate.

[0066] The second embodiment is an example in which the inner and outer peripheral fitting surfaces of the first fitting portion 22 are divided in the axial direction. The first fitting portion 22 is subjected to a bending moment due to a radial load. Therefore, it is more rational to design the total axial length of the first fitting portion 22 to be longer than the dimensions of the fitting portion determined from the required fitting force.

[0067] In the second embodiment, the length of the first fitting portion 22, which is determined from the required fitting force, is divided into two regions, one region (first region) is positioned on the tip side of the cantilever shaft portion 10, and the other region (second region) is positioned on the base side of the cantilever shaft portion 10.

[0068] 5, a cylindrical first region 31 and a second region 32, each of which constitutes part of the outer peripheral fitting surface 10a, are formed on the outer peripheral surface of the cantilever shaft portion 10 of the shaft 3. The first region 31 of the outer peripheral fitting surface 10a is formed on the tip side of the cantilever shaft portion 10. The second region 32 of the outer peripheral fitting surface 10a is formed on the base side of the cantilever shaft portion 10, spaced apart from the first region 31 in the axial direction.

[0069] The first region 31 and the second region 32 of the cantilever shaft portion 10 are each cylindrical and concentric with the rotation axis AX. The outer diameter of the first region 31 of the cantilever shaft portion 10 is set to be slightly smaller than the outer diameter of the second region 32 of the cantilever shaft portion 10. The axial fitting lengths of the first region 31 and the second region 32 are determined in proportion to the magnitude of the force acting thereon. Note that the fitting length of the first region 31 may be set to be shorter by utilizing the effect of the second fitting portion 28 to support the radial force.

[0070] In addition, between the first region 31 and the second region 32 of the cantilever shaft portion 10, an annular shaft side recess 33 is formed which is recessed radially inward compared to the first region 31 and the second region 32.

[0071] Meanwhile, a cylindrical first region 34 and a cylindrical second region 35, each constituting part of the inner peripheral fitting surface 11a1, are formed on the inner peripheral surface of the boss body 11a of the boss portion 11. The first region 34 of the inner peripheral fitting surface 11a1 is formed on one side of the boss body 11a (closer to the flange portion) and receives the first region 31 of the cantilever shaft portion 10. The second region 35 of the inner peripheral fitting surface 11a1 is formed on the other side of the boss body 11a, spaced axially from the first region 34, and receives the second region 32 of the cantilever shaft portion 10.

[0072] The first region 34 and the second region 35 of the boss body 11a are each cylindrical and concentric with the rotation axis AX. The inner diameter of the first region 34 of the boss body 11a is set slightly smaller than the inner diameter of the second region 35 of the boss body 11a. The difference in inner diameter between the first region 34 and the second region 35 of the boss body 11a corresponds to the difference in outer diameter between the first region 31 and the second region 32 of the cantilever shaft portion 10. The inner diameter of the first region 34 of the boss body 11a is a dimension that provides an interference fit with the first region 31 of the cantilever shaft portion 10, and the inner diameter of the second region 35 of the boss body 11a is a dimension that provides an interference fit with the second region 32 of the cantilever shaft portion 10.

[0073] Between the first region 34 and the second region 35 of the boss body 11a, an annular boss-side recess 36 is formed, which is recessed radially outward compared to the first region 34 and the second region 35.

[0074] When fitting the shaft 3 into the rotor 6, the cantilever shaft portion 10 is inserted into the boss portion 11 from the other side. At this time, as shown in FIGS. 5(a) and 5(b), the first region 31 of the cantilever shaft portion 10 passes through the second region 35 and the boss-side relief 36 of the boss body 11a and is inserted up to just before the first region 34. The second region 35 and the boss-side relief 36 of the boss body 11a both have larger inner diameters than the first region 34 of the boss body 11a. Therefore, the first region 31 of the cantilever shaft portion 10 can be inserted up to just before the first region 34 without interfering with the second region 35 and the boss-side relief 36 of the boss body 11a.

[0075] In the state shown in Figure 5(b), the first region 31 of the cantilever shaft portion 10 is located on the other side of the first region 34 of the boss body 11a and faces the boss-side relief 36 of the boss body 11a in the radial direction. The second region 32 of the cantilever shaft portion 10 is located on the other side of the second region 35 of the boss body 11a and is not inserted into the boss body 11a. Note that in the state shown in Figure 5(b), the second region 35 of the boss body 11a faces the shaft-side relief 33 of the cantilever shaft portion 10 in the radial direction.

[0076] 5(b), when the boss body 11a is pushed to the other side, the first region 31 of the cantilever shaft portion 10 and the first region 34 of the boss body 11a begin to fit together, and the second region 32 of the cantilever shaft portion 10 and the second region 35 of the boss body 11a begin to fit together almost simultaneously. Then, as shown in FIG. 5(c), the cantilever shaft portion 10 is pushed into the boss portion 11 until the first joint surface 10b of the cantilever shaft portion 10 comes into contact with the second joint surface 11b1 of the flange portion 11b.

[0077] 5(c), the first region 31 of the cantilever shaft portion 10 and the first region 34 of the boss body 11a are tightly fitted together, and the second region 32 of the cantilever shaft portion 10 and the second region 35 of the boss body 11a are tightly fitted together. As a result, as in the first embodiment, the outer mating surface 10a of the cantilever shaft portion 10 and the inner mating surface 11a1 of the boss body 11a are fitted together and come into surface contact, thereby forming the first mating portion 22. Therefore, in the second embodiment as well, the same effects as in the first embodiment can be obtained with respect to the first mating portion 22.

[0078] Furthermore, in the second embodiment, the fitting of the first region 31 of the cantilever shaft portion 10 into the first region 34 of the boss body 11a and the fitting of the second region 32 of the cantilever shaft portion 10 into the second region 35 of the boss body 11a proceeds almost simultaneously, significantly shortening the insertion allowance from the start of fitting to the end of fitting. For example, if the fitting portion of the first fitting portion 22 is equally divided into the first region (31, 34) and the second region (32, 35), the insertion allowance during fitting is reduced to 1 / 2.

[0079] When the insertion allowance from the start of insertion to the end of insertion is shortened, the stroke of the jig used for disassembly and assembly is also shortened, so in the second embodiment, it is possible to disassemble and assemble the hoist 1 in a smaller space than in the first embodiment. Also, in the second embodiment, the insertion allowance from the start of insertion to the end of insertion is shortened, so that the time required for disassembly and assembly of the hoist 1 can also be shortened.

[0080] <Third embodiment> FIG. 6 is a front view of the hoist 1 of the third embodiment, and FIG. 7 is a left side view of the hoist 1 of the third embodiment.

[0081] The third embodiment is an example in which the pin of the second fitting portion 28 is formed in a tapered shape. In the third embodiment, a tapered pin 40 having a smaller diameter at the front end than at the rear end is used as the pin of the second fitting portion 28. In addition, the pin holes 15, 17 of the cantilever shaft portion 10 and the flange portion 11b are formed in a tapered shape corresponding to the tapered pin 40.

[0082] Furthermore, a through hole 40a, which also serves as an air vent hole, is formed in the center of the tapered pin 40 along the axial direction, and a fastening bolt 41 is inserted into the through hole 40a. The fastening bolt 41 screws into a female threaded hole 42 formed in the bottom of the pin hole 15 of the cantilever shaft portion 10, and serves to fasten and fix the tapered pin 40 to the cantilever shaft portion 10.

[0083] To fit the tapered pin 40 in the third embodiment, the tapered pin 40 is inserted into the pin holes 15, 17 of the flange portion 11b and the cantilever shaft portion 10. Then, a tightening bolt 41 is inserted into the through hole 40a of the tapered pin 40, and the tightening bolt 41 is screwed into the female threaded hole 42 in the pin hole 15. As a result, the tapered pin 40 is fitted into the pin holes 15, 17 up to the interference, and the second fitting portion 28 is formed.

[0084] In the third embodiment, as shown in the following equations (14) and (15), the insertion allowance of the tapered pin 40 and the interference of the second fitting portion 28 can be determined with high precision. However, the insertion allowance of the tapered pin 40 and the interference of the second fitting portion 28 are set to zero at the moment when the tapered pin 40 and the pin holes 15, 17 come into contact. Insertion allowance of tapered pin 40 = Number of turns of fastening bolt 41 × Thread pitch ... Equation (14) Interference of the second fitting portion 28 = insertion allowance of the tapered pin 40 × taper ratio ... Equation (15)

[0085] In addition, when inserting the tapered pin 40 in the third embodiment, the insertion allowance from the start of insertion to the end of insertion is the value obtained by dividing the interference of the second fitting portion 28 by the taper ratio, as shown in formula (16). Insertion allowance of tapered pin 40 = Interference of second fitting portion 28 / Taper ratio ... Equation (16)

[0086] In the third embodiment, the moment when the tapered pin 40 contacts the pin hole 15 is set to zero, and the insertion amount of the tapered pin 40 can be precisely adjusted by rotating the tightening bolt 41. Also, in the third embodiment, the interference of the second fitting portion 28 can be precisely controlled by the insertion amount of the tapered pin 40, so that variations in the interference among the multiple second fitting portions 28 can be suppressed.

[0087] For example, if the taper ratio in equation (15) is 1 / 50, the interference of the second fitting portion 28 in the third embodiment is 1 / 50 in diameter of the insertion amount of the tapered pin 40, and the precision of the interference (radius) is 100 times the insertion amount. Therefore, it can be seen that in the case of the third embodiment, the variation in interference can be reduced compared to the case of the first embodiment, where the machining tolerances of the cylindrical pin and pin hole are controlled.

[0088] In this way, in the third embodiment, the variation in the fitting friction force proportional to the interference is reduced, so the maximum fitting friction force of the second fitting portion 28 can be designed to be small, taking the variation into consideration. For the above reasons, in the third embodiment, the fitting friction force at the second fitting portion 28 can be reduced compared to the first embodiment.

[0089] Furthermore, in the third embodiment, the insertion allowance from the start to the end of insertion of the tapered pin 40 is significantly shortened when disassembling and assembling the second fitting portion 28. Therefore, in the third embodiment, the disassembly and assembly work of the second fitting portion 28 is easier than in the first embodiment, and the work time can also be reduced.

[0090] For example, the required interference for the second fitting portion 28 is assumed to be a diameter of 20 μm and a taper ratio of 1 / 50. In this case, from equation (16), the insertion allowance of the tapered pin 40 is 1 mm. On the other hand, if a cylindrical pin is used as in the first embodiment, the pin insertion allowance will be several tens of mm or more, so it can be seen that the pin insertion allowance in the third embodiment is significantly shorter than that in the first embodiment.

[0091] <Fourth embodiment> Fig. 8 is a front view of the hoist 1 of the fourth embodiment, and Fig. 9 is a left side view of the hoist 1 of the fourth embodiment. The partial cross section of the shaft 3 and the rotor 6 in Fig. 8 is a cross section taken along line BOJDE in Fig. 9.

[0092] In the fourth embodiment, extraction screw holes 43 into which extraction screws (not shown) are screwed are formed in the flange portion 11b. The number of extraction screw holes 43 is set so that the product of the axial force of the extraction screws and the number of the extraction screws is greater than the engagement friction force of the first fit-up portion 22. Fig. 9 shows an example in which four extraction screw holes 43 are formed at equal intervals in the circumferential direction of the flange portion 11b.

[0093] In the fourth embodiment, when disassembling the shaft 3 and rotor 6, a pull-out screw is threaded into the pull-out screw hole 43. The pull-out screw then comes into contact with the first joint surface 10b of the cantilever shaft portion 10, generating a force that pulls the rotor 6 out of the cantilever shaft portion 10. The rotor 6 then moves away from the cantilever shaft portion 10 in proportion to the amount of threading of the pull-out screw, thereby allowing the shaft 3 and rotor 6 to be disassembled. According to the fourth embodiment, the shaft 3 and rotor 6 can be disassembled by threading the pull-out screw into the flange portion 11b, which makes it possible to simplify the pull-out jig and reduce the effort required for disassembly.

[0094] <Supplementary information on the embodiment> The present invention is not limited to the above-described embodiments, and various improvements and design changes may be made without departing from the spirit of the present invention. For example, any combination of the configurations of the first to fourth embodiments may be applied.

[0095] In the above embodiment, the outer peripheral fitting surface 10a and the inner peripheral fitting surface 11a1 that constitute the first fitting portion 22 may be formed in a tapered shape that reduces in diameter from the other side to one side.

[0096] Furthermore, the shape of the mating surface of the first mating portion 22 in the second embodiment is not limited to the above-described shape as long as interference between the inner peripheral surface of the boss and the outer peripheral surface of the shaft can be avoided. For example, the portion of the cantilever shaft portion 10 distal to the second region 32 may be formed in a cylindrical shape flush with the outer diameter of the first region 31, eliminating the need for a groove-like relief. Alternatively, the portion of the boss body 11a on the other side of the first region 34 may be formed in a cylindrical shape flush with the inner diameter of the second region 35, eliminating the need for a groove-like relief. Note that, as long as interference between the inner peripheral surface of the boss and the outer peripheral surface of the shaft can be avoided, the first region 31 and the second region 32 of the cantilever shaft portion 10 may be connected in a tapered shape, or the first region 34 and the second region 35 of the boss body 11a may be connected in a tapered shape.

[0097] In the above embodiment, a configuration example in which the present invention is applied to an elevator hoist has been described. However, the present invention can be applied to any hoist that hoists a rope.

[0098] Furthermore, the embodiments disclosed herein should be considered to be illustrative and not restrictive in all respects. The scope of the present invention is defined by the claims, not by the above description, and is intended to include all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0099] DESCRIPTION OF SYMBOLS 1...hoisting machine, 2...driving sheave, 3...shaft, 6...rotor, 7...stator, 10...cantilever shaft portion, 10a...outer peripheral fitting surface, 10b...first joint surface, 11...boss portion, 11a...boss body, 11a1...inner peripheral fitting surface, 11b...flange portion, 11b1...second joint surface, 15, 17...pin hole, 16, 18...bolt hole, 19...fixing bolt, 22...first fitting portion, 24...joint portion, 26...pin, 28...second fitting portion, 31, 34...first region, 32, 35...second region, 40...tapered pin, 41...fastening bolt, 42...female threaded hole, 43...withdrawal screw hole

Claims

1. a drive sheave for winding and unwinding the rope; a shaft disposed along the rotation axis of the traction sheave and rotating the traction sheave; a rotor attached to one end of the shaft and rotated by a magnetic force acting against the magnetic field of the stator; the rotor has a boss portion that forms a first fitting portion and a plurality of second fitting portions between the rotor and the shaft; the boss portion has a cylindrical main body into which one end of the shaft is inserted, and a flange portion that protrudes from the inner periphery of the cylindrical main body and faces an end surface on the one end side of the shaft, In the first fitting portion, an inner peripheral surface of the cylindrical main body and an outer peripheral surface of the shaft are fitted together, In each of the second fitting portions, a pin is inserted through the flange portion and fitted axially onto the shaft, and the flange portion and the shaft are fitted together via the pin, a first joint surface perpendicular to the rotation axis is formed at one end of the shaft; a second joint surface perpendicular to the rotation axis is formed on the flange portion so as to face the first joint surface; The shaft further includes a joint portion to which the flange portion and the shaft are fixed with a fixing bolt while the first joint surface and the second joint surface are in contact with each other, The first fitting portion has a first region provided on the tip side of the shaft and a second region provided at a distance from the first region in the axial direction, and the inner peripheral surface of the cylindrical main body and the outer peripheral surface of the shaft are fitted together, an outer diameter of the shaft is smaller at a portion corresponding to the first region than at a portion corresponding to the second region; The inner diameter of the cylindrical body is smaller in a portion corresponding to the first region than in a portion corresponding to the second region. Hoisting machine.

2. The pin has a tapered shape in which the diameter decreases toward the tip end in the insertion direction, When the second fitting portion is fitted, the pin is fastened to the shaft by a bolt inserted into the pin. The hoist according to claim 1.

3. The flange portion has a screw hole into which a pull-out screw can be screwed, which presses one end of the shaft when the rotor and the shaft are disassembled. The hoist according to claim 1 or 2.

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