Electric chain block

Abstract

To provide an electric chain block capable of using a small-sized and high-efficient motor, and reduced in size by placing a friction clutch mechanism and a brake mechanism adjacently.SOLUTION: An electric chain block 10 comprises: a load sheave 80, a motor 30 to rotate the load sheave 80; a drive transmission shaft 60 to transmit the driving force from the motor 30 to the load sheave 80; a brake mechanism 50 to apply the brake force for stopping the rotation of the drive transmission shaft 60; and a friction clutch mechanism 40 comprising an input side disc 41 disposed on the edge side in the axial direction of a motor shaft 34, an output side disc 42 disposed in a brake hub 52 to transmit the driving force to the drive transmission shaft 60, a friction plate 43 sandwiched between the input side disc 41 and the output side disc 42, and a disc spring 45 to apply the energizing force that presses the friction place 43 (friction member) against the input side disc 41 and the output side disc 42.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to an electric chain hoist. [Background technology]

[0002] In an electric chain block that uses the driving force of a motor to raise and lower a load, as shown in Patent Document 1, for example, there is a configuration that includes a motor (22), a friction clutch mechanism (30), a drive transmission shaft (40), a load sheave (60), a brake mechanism (70), and a control circuit (80).

[0003] In this configuration, a driving force is transmitted from the motor (22) to the speed reduction mechanism (50) and the brake mechanism (70) via the friction mechanism (30). The components are arranged such that the speed reduction mechanism (50), the brake mechanism (70), and the control circuit (80) are arranged on one side (the left side in FIG. 2) of the load sheave (60), and the motor (22) and the friction clutch mechanism (30) are arranged on the other side (the right side in FIG. 2).

[0004] Furthermore, electric chain hoists are generally of the type that are powered by a power source, but there are also battery-powered electric chain hoists, as shown in Patent Document 2. The configuration shown in Patent Document 2 includes a battery pack (1), a control device (2), a motor (4), a brake (5), and a reduction mechanism (6). The arrangement of the components is disclosed as follows: the control device (2), motor (4), and reduction mechanism (6) are arranged on one side of the load sheave (the portion around which the link chain (7) is wound), and the battery pack (1) and brake (5) are arranged on the other side. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] WO2022 / 085629 publication [Patent Document 2] Publication number CN201068378Y Summary of the Invention [Problem to be solved by the invention]

[0006] Incidentally, the electric chain hoist as disclosed in Patent Document 1 has a structure in which a bearing is disposed inside the rotor of the motor, and therefore the motor inevitably becomes large in size.

[0007] In addition, the battery-powered electric chain hoist shown in Patent Document 2 has a motor (4) and a speed reducer (6) arranged on the same side, and has a vertically long frame structure.

[0008] The present invention has been made in consideration of the above circumstances, and has as its object to provide an electric chain hoist that can use a small, highly efficient motor, has a friction clutch mechanism and a brake mechanism arranged adjacent to each other to reduce its size, and is preferably highly productive and has a reduced number of parts. [Means for solving the problem]

[0009] In order to solve the above problems, according to a first aspect of the present invention, there is provided an electric chain hoist that winds up or lowers a load chain connected to a hook for hanging a load, comprising: a load sheave that winds up or lowers the load chain by rotating; a motor that provides driving force to rotate the load sheave; a drive transmission shaft that transmits the driving force from the motor to the load sheave; a brake mechanism that applies braking force to stop the rotation of the drive transmission shaft; an input side disc arranged on the axial end side of the motor shaft of the motor; an output side disc that transmits the driving force to the drive transmission shaft; a friction clutch mechanism that includes: an input side disc arranged on the axial end side of the motor shaft;

[0010] In the above-mentioned invention, it is preferable that the motor, the brake mechanism, and the friction clutch mechanism constitute a single drive unit.

[0011] Furthermore, in the above-described invention, it is preferable that the motor includes a motor frame for fixing a stator of the motor, the brake mechanism includes a brake stator facing a brake rotor, the motor frame and the brake stator are fixed to each other, and an internal space is formed between them by this fixing, and the input side disc, output side disc, friction plate and biasing member that constitute the friction clutch mechanism are arranged in the internal space.

[0012] Furthermore, in the above-described invention, it is preferable that the motor shaft has a hollow portion along the axial direction of the motor shaft, a rod-shaped adjustment rod is inserted into the hollow portion, the friction clutch mechanism has a spring bearing member that presses the biasing member toward the input side disc, a male threaded portion that is screwed into the female threaded portion provided in the hollow portion is disposed on one axial end side of the adjustment rod, and the spring bearing member is disposed in abutting contact with the other axial end side of the adjustment rod, and the biasing force of the biasing member can be adjusted by screwing in the male threaded portion and pressing the spring bearing member via the adjustment rod,

[0013] In the above-mentioned invention, the motor is preferably a PM motor.

[0014] In addition, in the above-described embodiment, it is preferable that a drive unit or a motor is arranged on one side of the load sheave in the axial direction, and a battery that supplies power to the motor is arranged on the other side of the load sheave in the axial direction. [Effects of the Invention]

[0015] According to the present invention, it is possible to provide an electric chain hoist that can use a small, highly efficient motor, can be made compact by arranging the friction clutch mechanism and brake mechanism adjacent to each other, and preferably has excellent productivity and allows for a reduced number of parts. [Brief explanation of the drawings]

[0016] [Figure 1] 1 is a perspective view showing a configuration of an electric chain block according to an embodiment of the present invention. [Figure 2] 2 is a cross-sectional view showing the electric chain hoist shown in FIG. 1 cut along an XY plane passing through the center of a motor shaft. [Figure 3] 2 is a perspective view showing a cross section of the drive unit in the electric chain hoist shown in FIG. 1 taken along an XZ plane along the axial direction (X direction). FIG. [Figure 4]FIG. 2 is an exploded perspective view showing the configuration of a friction clutch mechanism and a motor shaft in the electric chain block shown in FIG. [Figure 5] 10 is a view showing a state in which a protrusion for preventing displacement of a friction plate is present on the inner diameter side according to a modified example of the present invention. FIG. [Figure 6] FIG. 10 is a view showing a modified example of the present invention, in which a cylindrical displacement prevention member for preventing displacement of the friction plate is arranged on the outer periphery. [Figure 7] 3 is a cross-sectional view showing a modified example of the electric chain block according to the present invention, which has a different configuration from that shown in FIG. 2. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0017] An electric chain hoist 10 according to one embodiment of the present invention will be described below with reference to the drawings. In the following description, the Z direction refers to the direction in which the load chain C1 is lifted or lowered, the Z1 side refers to the side where the upper hook 13 is located, and the Z2 side refers to the opposite side where the lower hook 14 is located.

[0018] The X direction refers to the longitudinal direction (axial direction) of the motor shaft 34, the X1 side refers to the right side in Fig. 2, and the X2 side refers to the opposite, left side. The Y direction refers to the direction perpendicular to the Z direction and the X direction, the Y1 side refers to the lower right side in Fig. 1, and the Y2 side refers to the opposite, upper left side.

[0019] <Overall structure of the chain block> Fig. 1 is a perspective view showing the configuration of an electric chain hoist 10 according to one embodiment of the present invention. Fig. 2 is a cross-sectional view showing the electric chain hoist 10 shown in Fig. 1 cut along the XY plane at the center of the motor shaft 34. As shown in Figs. 1 and 2, the electric chain hoist 10 includes, as components that can be seen from the outside, a housing 11, a battery unit 12, an upper hook 13, a lower hook 14, a chain bucket 15, and a load chain C1.

[0020] The housing 11 is a box-shaped part made of aluminum alloy that has an internal space for accommodating each component part, and constitutes most of the exterior of the electric chain hoist 10. Note that the housing 11 may be made of a material other than aluminum alloy.

[0021] The electric chain hoist 10 of this embodiment is battery-powered, and a battery unit 12 is disposed on the other side (X2 side) of the housing 11 in the axial direction (X direction). The battery unit 12 has a battery body 12a (corresponding to the battery) and a case 12b. The battery body 12a supplies power to a motor 30 (described later) via a control circuit 90. The case 12b houses the battery body 12a and has a lid (reference numeral omitted) that can be opened and closed.

[0022] 1 and 2, in this embodiment, the battery unit 12 has a case 12b that has a design that is consistent with the housing 11 and that functions to protect the battery main body 12a. However, the battery unit 12 may not have such a case 12b, and may instead be a general-purpose battery that is widely used in power tools and is directly attached to the housing 11.

[0023] The upper hook 13 is a hook that can be hung on a beam or wire rope that has enough strength to withstand the load of the load that the electric chain hoist 10 is suspended from.

[0024] The lower hook 14 is a part that is hooked onto a load or the like, and is connected to the end of the load chain C1. With a load hooked onto the lower hook 14, the electric chain hoist 10 can raise and lower the load by winding up and lowering the load chain C1.

[0025] In this embodiment, the load chain C1 hangs down from an opening (not shown) provided in the lower part of the housing 11.

[0026] The chain bucket 15 is a fabric bucket that is connected in a suspended state via a metal fitting 15a provided on the side surface 11a of the housing 11 and a connection link 15c connected to the metal fitting, and that houses the wound-up load chain C1. When the load chain C1 is wound down by the load sheave 80, which will be described later, the load chain C1 is paid out into the chain bucket 15 from an opening (not shown) provided in the side surface 11a of the housing 11.

[0027] Next, we will explain the components of the electric chain hoist 10 housed inside the housing 11. As shown in Fig. 2, the housing 11 contains a drive unit 20, a drive transmission shaft 60, a speed reduction mechanism 70, a load sheave 80, a control circuit 90, and an antenna 100.

[0028] 3 is a perspective view showing a cross section of the drive unit 20 taken along an XZ plane along the axial direction (X direction). As shown in FIGS. 2 and 3, the drive unit 20 includes a motor 30, a friction clutch mechanism 40, and a brake mechanism 50. Of these, the motor 30 is, for example, a PM (Permanent Magnet) motor, which is a type of synchronous motor, and provides driving force to a load sheave 80 (described later). The motor 30 includes a motor frame 33 that covers a rotor 31 having a permanent magnet and a stator 32 having a coil. The motor frame 33 includes a cylindrical motor frame outer periphery 33a that covers the outer periphery of the stator 32, a motor frame side end 33b that covers the other axial side (output side) of the outer periphery 33a, and a motor frame cover 33c that covers one side (non-output side).

[0029] A motor shaft 34 that rotates integrally with the rotor 31 is provided at the radial center of the rotor 31. A bearing B1 supported by a motor frame cover 33c of the motor frame 33 is disposed on one axial side (X direction) (X1 side) of the motor shaft 34, and a bearing B2 supported by a side end wall 33b1 of the motor frame side end 33b is disposed on the other axial side (X2 side), and the motor shaft 34 is journaled to the motor frame 33 via the bearings B1 and B2. The motor frame outer peripheral portion 33a and the motor frame side end 33b may be integrally molded.

[0030] The stator 32 or the motor frame outer peripheral portion 33a is attached to the housing 11 by a flange portion 20f formed on the motor frame lid 33c with mounting screws (not shown). Therefore, the drive unit 20 can be removed as a unit by removing the screw parts (not shown) that secure the flange portion 20f to the housing 11.

[0031] Additionally, a side end cylindrical portion 33b2 is provided at the motor frame side end 33b. The side end cylindrical portion 33b2 is provided to protrude from the side end wall 33b1 to the other side (X2 side) in the axial direction (X direction), and the end of the protruding side abuts against and positions a stator 51a (described later) of the brake mechanism 50. The presence of this side end cylindrical portion 33b2 forms an internal space SP1 between the side end wall 33b1 and the stator 51a, in which the friction clutch mechanism 40 can be disposed.

[0032] The motor shaft 34 is hollow and has a hollow portion 34a that penetrates the motor shaft 34 in the axial direction (X direction). An adjustment rod 35 is inserted into the hollow portion 34a. A female thread portion 34b is provided at one end (X1 side) of the hollow portion 34a in the axial direction (X direction). An adjustment screw 36 is screwed into the female thread portion 34b. A rotation prevention portion 34e is formed on the outer periphery of the motor shaft 34 where the female thread portion 34b is located, with part of the outer periphery, such as a flat width face, being flat. The rotation prevention portion 34e has a non-circular outer shape so that a spanner wrench or the like can be fitted to prevent rotation of the motor shaft 34 when screwing in the adjustment screw 36.

[0033] The adjustment rod 35 is a long, rod-shaped member. One end (X1 side) of the adjustment rod 35 abuts against the adjustment screw 36, and the other end (X2 side) abuts against a spring bearing member 44 (described later). Therefore, by adjusting the amount that the adjustment screw 36 is screwed into the female thread portion 34b, the adjustment rod 35 moves forward and backward in the axial direction (X direction), thereby making it possible to adjust the amount by which the adjustment rod 35 presses against the disc spring body 45 via the spring bearing member 44 in the axial direction (X direction). In this embodiment, the adjustment rod 35 and the adjustment screw 36 are provided separately, but a male screw may be provided integrally with one end (X1 side) of the adjustment rod 35.

[0034] The adjusting screw 36 may be, for example, a set screw having a male thread 36a formed on its outer periphery, which can be screwed into the female thread 34b. A nut 37 for preventing loosening is screwed into the male thread 36a.

[0035] 4 is an exploded perspective view showing the configuration of friction clutch mechanism 40 and motor shaft 34. As shown in Fig. 4, friction clutch mechanism 40 is a mechanism for preventing an overload caused by the drive torque of motor 30 from being transmitted from motor shaft 34 to drive transmission shaft 60. This friction clutch mechanism 40 has an input side disc 41, an output side disc 42, a friction plate 43, a spring bearing member 44, and a disc spring body 45.

[0036] The input-side disk 41 is a member coupled to the motor shaft 34 so as to rotate and transmit torque with the motor shaft 34. In the configuration shown in FIG. 4, an engagement hole 41a is provided in the radial center of the input-side disk 41, and this engagement hole 41a is provided in a hole shape other than circular (generally low barrel-shaped in FIG. 4). Meanwhile, a shaft engagement portion 34d is provided on the other end (X2 side) of the motor shaft 34 in the axial direction (X direction). The shaft engagement portion 34d is provided in a shaft shape (generally low barrel-shaped with two branches in FIG. 4) that is inserted into the engagement hole 41a of the input-side disk 41 and coupled so as to transmit torque. Therefore, when the shaft engagement portion 34d is inserted into the engagement hole 41a, the motor shaft 34 and the input-side disk 41 rotate slidably in the axial direction and are capable of transmitting torque. In this embodiment, the engagement hole 41a of the input side disk 41 is low and barrel-shaped, but it may be, for example, approximately elliptical, hourglass-shaped, or rectangular, and the shaft engagement portion that engages with the engagement hole may have an outer circumferential appearance that fits non-rotatably into the engagement hole. Alternatively, the engagement hole and the shaft engagement portion may be circular and spline-connected.

[0037] The input-side disc 41 also has an outer circumferential ring portion 41c that protrudes from the outer circumferential edge of its surface 41b (the surface facing the output-side disc 42). The outer circumferential ring portion 41c is a portion that prevents the friction plate 43, which is in contact with the surface 41b, from moving in the radial direction. The protruding height of the outer circumferential ring portion 41c is sufficient to prevent radial movement, and is, for example, less than half the thickness of the friction plate 43.

[0038] The output side disc 42 is a member connected to the brake hub 52 of the brake mechanism 50 (described later) so as to rotate integrally with the brake hub 52. In addition, the output side disc 42 is a member to which driving force is transmitted via a friction plate 43 when the input side disc 41 is driven by the motor 30 via the motor shaft 34. The output side disc 42 has an engagement hole 42a formed on the radial center side thereof, and is connected to the brake hub 52 via this engagement hole 42a.

[0039] Here, the engagement hole 42a and the brake hub 52 are configured to rotate and transmit torque, for example, by a spline connection. In the configuration shown in Fig. 4, the engagement hole 42a is splined, but a connection method other than spline processing may also be used. Furthermore, the engagement hole 42a and the brake hub 52 are preferably fixed by press-fitting, but may also be fitted together to allow sliding in the axial direction.

[0040] Similar to the outer ring portion 41c, the output side disc 42 has an outer ring portion 42c protruding from the outer periphery of its surface 42b (the surface facing the input side disc 41) to prevent the friction plates 43 from moving in the radial direction. The protruding height of the outer ring portion 42c is set higher than that of the outer ring portion 41c, but it may also be set to the same height. The outer ring portions 41c, 42c are protrusions that prevent the friction plates 43 from shifting position when adjusting the upper limit torque transmission (set load) of the friction clutch mechanism 40.

[0041] Furthermore, protrusions may be provided on the inner diameter side of at least one of the surfaces 41b and 42b. Such protrusions on the inner diameter side may prevent the friction plate 43 from shifting position. Fig. 5 is a diagram showing such a state. Note that Fig. 5 shows a configuration in which the protrusion 42d protrudes from the inner diameter side of the surface 42b, but a configuration in which the protrusion protrudes from the inner diameter side of the surface 41b may also be employed, or a configuration in which the protrusions protrude from both the inner diameter side of the surface 41b and the inner diameter side of the surface 42b may also be employed.

[0042] Furthermore, although it has been described that the misalignment prevention portion that prevents the friction plate 43 from shifting position is integrally molded with the input side disc 41 or the output side disc 42, a cylindrical misalignment prevention member may be provided on the outer periphery of the input side disc 41 or the output side disc 42, or both.

[0043] Fig. 6 is a diagram showing an example of such a configuration. In Fig. 6, a cylindrical displacement prevention member 46 is disposed on the outer periphery of the input side disc 41, the output side disc 42, and the friction plate 43. In the configuration shown in Fig. 6, the displacement prevention member 46 is fixed integrally to the input side disc 41, but is not fixed to the output side disc 42. However, a configuration may also be employed in which the displacement prevention member 46 is fixed integrally to the output side disc 42, but is not fixed to the input side disc 41.

[0044] The friction plate 43 is a ring-shaped member formed into a disk shape from a predetermined friction material (such as a woven friction material, a resin-molded friction material, or a sintered material made by sintering a material containing metal). The friction plate 43 corresponds to a friction member. When a rotational driving force greater than the friction force between the friction plate 43 and the surface 41b of the input-side disc 41 acts, slippage occurs between the friction plate 43 and the surface 41b. Similarly, when a rotational torque greater than the torque (upper limit transmission torque) caused by the friction force between the friction plate 43 and the surface 42b of the output-side disc 42 acts, slippage occurs between the friction plate 43 and the surface 42b. This prevents an overload exceeding the upper limit transmission torque (set load) from acting on components of the electric chain hoist 10, such as the load chain C1, and parts connected to the electric chain hoist 10, thereby preventing damage.

[0045] The spring bearing member 44 is a portion that engages with the shaft engaging portion 34d located on the other end (X2 side) of the motor shaft 34 in the axial direction (X direction). As shown in FIG. 4, in this embodiment, the spring bearing member 44 engages with the shaft engaging portion 34d and is provided in a substantially θ-shape. Specifically, the spring bearing member 44 is provided with an annular spring bearing portion 44a and a pressing force receiving portion 44b. One end and the other end of the pressing force receiving portion 44b are connected to the spring bearing portion 44a, thereby forming a bridge-like portion that divides the center hole of the spring bearing portion 44a into two. The shaft engaging portion 34d is bifurcated and has a groove portion 34d1 for accommodating the pressing force receiving portion 44b of the spring bearing member 44. The groove 34d1 communicates with the hollow portion 34a, and the other end of the adjustment rod 35d is disposed in the hollow portion 34a and is positioned in the groove 34d1.

[0046] Although the spring receiving portion 44a in this embodiment has an annular shape, it may have any shape as long as it extends from both ends of the pressure receiving portion 44b in the centrifugal direction and can press the disc spring body 45 toward the input-side disc 41. Furthermore, it is preferable that the spring receiving member 44 has the spring receiving portion 44a wider than the groove width of the groove portion 34d1, such as a substantially θ-shaped, substantially I-shaped, or substantially H-shaped, and is provided with a position displacement prevention portion 44a1. Furthermore, the shaft engaging portion 34d may have any shape other than a bifurcated shape as long as it can accommodate the pressure receiving portion 44b of the spring receiving member 44 in accordance with the shape of the spring receiving member 44.

[0047] 3 and 4, the adjustment rod 35 abuts against the pressure receiving portion 44b. Therefore, when the amount of screwing of the adjustment screw 36 is adjusted, the pressing position of the pressure receiving portion 44b is also adjusted via the adjustment rod 35. Here, the spring receiving member 44 presses the disc spring body 45, and the disc spring body 45 presses the input-side disc 41. Therefore, when the amount of screwing of the adjustment screw 36 is adjusted, the friction force of the friction plate 43 between the input-side disc 41 and the output-side disc 42 can be adjusted via the adjustment rod 35 and the spring receiving member 44, thereby making it possible to adjust the upper limit torque transmission limit.

[0048] The disc spring body 45 corresponds to the biasing member. The disc spring body 45 is a member made up of a plurality of disc springs 45a, but a single disc spring or a member other than the disc spring 45a may be used as the biasing member. An example of such a member is a coil spring.

[0049] Next, the brake mechanism 50 will be described. The brake mechanism 50 is, for example, a non-excitation actuation type electromagnetic brake, which is a mechanism that stops the rotation of a brake hub 52 when not excited. This brake mechanism 50 has an electromagnetic brake unit 51 and a brake hub 52. The electromagnetic brake unit 51 has a stator 51a that incorporates an electromagnetic coil (not shown), an armature 51b, a plate 51c, a rotor 51d, and a brake spring (compression coil spring) (not shown) embedded in the stator 51a. The stator 51a corresponds to the brake stator, and the rotor (friction plate) 51d corresponds to the brake rotor.

[0050] The stator 51a, armature 51b, and plate 51c are all non-rotating components, but the rotor 51d is axially slidable relative to the brake hub 52 and coaxially rotates to transmit torque. Of these components, the stator 51a and armature 51b are made of a magnetic material, such as an iron-based metal, that forms a magnetic circuit. The armature 51b is guided by a support shaft (not shown) and is slidable along the support shaft but not rotatable relative to the stator 51a. A brake spring (not shown) applies a biasing force to the armature 51b in a direction pressing the rotor 51d against the rotor 51d. The plate 51c is fixed to the stator 51a by a support shaft (not shown) so as to maintain a predetermined distance, and the armature 51b and rotor 51d are coaxially arranged within the predetermined distance, starting from the stator 51a. A square hole 51d1 is formed in the center of the rotor 51d, and the rotor 51d is slidably engaged with a square shaft portion (outer peripheral connecting portion) 52b of the brake hub 52 by the square hole 51d1.

[0051] Therefore, when the electromagnetic coil is de-energized, the armature 51b is pressed by the biasing force of a brake spring (not shown), and the armature 51b presses and sandwiches the rotor 51d against the plate 51c, so that a braking force acts on the rotor 51d and the rotor 51d and the brake hub 52 become unrotatable. However, when the electromagnetic coil is energized, the stator 51a pulls the armature 51b toward one side (X1 side) in the axial direction (X direction) against the biasing force of the brake spring, and the sandwiching (pressure) of the rotor 51d between the armature 51b and the plate 51c is released. This allows the rotor 51d and the brake hub 52 to rotate.

[0052] A bearing B3 that supports the rotation of the brake hub 52 is attached by press fitting to the brake hub 52. The bearing B3 is embedded in the surface of the stator 51a facing the output-side disc 42, and the bearing B3 press-fitted into the brake hub 52 prevents the brake hub 52 from moving away from the stator 51a toward the load sheave 80. Preferably, the output-side disc 42 is press-fitted into the outer peripheral connecting portion 52b that protrudes from the bearing B3 of the brake hub 52 toward the friction clutch mechanism 40 (one side) while the brake hub 52 is assembled to the bearing B3 arranged on the stator 51a. Alternatively, a stopper member such as a snap ring may be provided to prevent axial displacement of the brake hub 52 and the output-side disc 42. The press-fitting of the bearing B3, the press-fitting of the output-side disc 42, or the provision of a snap ring into the brake hub 52 constitutes a means for preventing axial displacement of the brake hub 52, and it is preferable to provide at least one of these.

[0053] The brake hub 52 is a member that is connected to the rotor 51d and the output-side disc 42 so as to be able to transmit torque and that rotates coaxially. An inner periphery connecting portion 52a formed by splining or the like is provided on the inner periphery of the other axial side (X direction) (X2 side) of the brake hub 52. An outer periphery connecting portion 61 formed by splining or the like on one axial side (X direction) (X1 side) of the drive transmission shaft 60 is connected to the inner periphery connecting portion 52a. This allows the brake hub 52 to rotate together with the output-side disc 42 and the drive transmission shaft 60 so as to be able to transmit torque.

[0054] In this embodiment, the motor 30, the friction clutch mechanism 40, and the brake mechanism 50 are provided integrally to form the integrated drive unit 20. Therefore, in the stage of manufacturing the electric chain hoist 10, the drive unit 20 is assembled as a single unit, and then the integrated drive unit 20 is attached to a predetermined position inside the housing 11. Furthermore, when performing maintenance on the electric chain hoist 10, the integrated drive unit 20 is removed from inside the housing 11.

[0055] The battery unit 12 is disposed on the other side (X2 side) in the axial direction (X direction) of the load sheave 80. The capacity of the battery body 12a in the battery unit 12 is determined in consideration of the balance of the center of gravity of the entire electric chain hoist 10. In the embodiment of Fig. 2, the motor 30, friction clutch mechanism 40, brake mechanism 50, and control circuit 90 are disposed on one side of the load sheave 80, making it possible to mount a large-capacity battery.

[0056] Next, the drive transmission shaft 60 will be described. The drive transmission shaft 60 is a rotating shaft for transmitting the driving force from the drive unit 20 to the load sheave 80 via the speed reduction mechanism 70. This drive transmission shaft 60 is provided with an outer circumferential coupling portion 61 that is splined or the like on its outer periphery. Therefore, when the inner circumferential coupling portion 52a of the brake hub 52 meshes with this outer circumferential coupling portion 61, the drive transmission shaft 60 transmits torque coaxially with the brake hub 52.

[0057] The drive transmission shaft 60 is inserted through a central hole 81 of the load sheave 80, and is provided with a pinion gear 62 on the other end side (X2 side) in the axial direction (X direction) of the drive transmission shaft 60. The pinion gear 62 is in mesh with a large diameter gear 71a of a driven gear member 71 that constitutes the reduction mechanism 70.

[0058] The reduction gear mechanism 70 also has a driven gear member 71 and a load gear 72. The driven gear member 71 has a large-diameter gear 71a that meshes with the pinion gear 62, and further has a small-diameter gear 71b that is coaxial with the large-diameter gear 71a and rotates integrally with the large-diameter gear 71a. The small-diameter gear 71b meshes with the load gear 72. The load gear 72 is a gear attached to the other end (X2 side) in the axial direction (X direction) of a load sheave shaft 80a, which is the shaft portion of the load sheave 80.

[0059] Next, the load sheave 80 will be described. The load sheave 80 is integrally provided with a load sheave shaft 80a, which is the shaft portion of the load sheave 80. Both ends of this load sheave shaft 80a are journaled to the housing 11 by bearings (reference numeral omitted). The load sheave 80 also has a center hole 81 along its axis. Therefore, the load sheave shaft 80a is also a hollow shaft member. The drive transmission shaft 60 is coaxially disposed to pass through the center hole 81. The load sheave 80 has a plurality of chain pockets (reference numeral omitted), into which the metal rings of the load chain C1 can fit.

[0060] A chain guide 11b is provided on the outer periphery of the load sheave 80, which guides the load chain C1 from the two openings of the housing 11 to the outer periphery of the load sheave 80 and also guides the meshing of the load chain C1 with the load sheave. Therefore, by driving the motor 30, it is possible to wind up and down the load chain C1.

[0061] The electric chain hoist 10 is also provided with a control circuit 90. The control circuit 90 is a circuit for controlling the operation of the motor 30, and in Fig. 2, it is provided inside the housing 11 on one side (X1 side) in the axial direction (X direction) of the motor shaft 34. The control circuit 90 includes a memory (not shown), which stores programs and data for executing desired control.

[0062] The electric chain hoist 10 also includes an antenna 100. The antenna 100 is provided separately from the main body of the electric chain hoist 10 and receives signals from the operating device 110. The signal received by the operating device 110 is transmitted to the control circuit 90, which then controls the operation of the motor 30 based on this signal (operation command).

[0063] The operation device 110 includes a control unit 111 and an operation switch 112. The control unit 111 receives an input signal from the operation switch 112 and wirelessly transmits a predetermined signal to the antenna 100. The operation device 110 is preferably provided outside the housing 11 and configured to be portable by the user or configured to be held integrally with the operation switch 112. Alternatively, the operation device 110 may be configured to transmit an operation signal from the operation switch 112 to the control circuit 90 via a wired connection.

[0064] <About the action> In the electric chain hoist 10 configured as described above, when the motor 30 is driven, the drive torque of the motor shaft 34 is transmitted to the brake hub 52 via the friction clutch mechanism 40. The drive torque is then transmitted to the drive transmission shaft 60 via the brake hub 52, and the drive torque is reduced in the speed reduction mechanism 70 before being transmitted to the load sheave 80, enabling the load chain C1 to be wound up or down.

[0065] In a situation where an overload may occur, such as when the weight of the suspended load exceeds the rated load of the electric chain hoist 10 or when earth suspension occurs, slippage occurs at least between the input side disc 41 and the friction plate 43 and between the output side disc 42 and the friction plate 43, preventing an overload from acting on each part of the electric chain hoist 10.

[0066] Furthermore, when power is not supplied to the electromagnetic coil in the stator 51a of the brake mechanism 50, the rotor 51d and the brake hub 52 connected to the rotor 51d are braked, and the drive transmission shaft 60 connected to the brake hub 52 is also braked. The load sheave 80, to which driving force is transmitted to the drive transmission shaft 60 via the speed reduction mechanism 70, is also braked. Therefore, even if a problem occurs in the friction clutch mechanism 40, the load lifted by the lower hook 14 can still be held.

[0067] The upper limit torque transmission capacity of the friction clutch mechanism 40 is adjusted by the amount of tightening of the adjustment screw 36. To adjust the upper limit torque transmission capacity, the motor 30 of the electric chain hoist 10 is driven and the tension of the load chain C1 is measured using a load cell or similar device. The friction clutch mechanism 40 does not have a through-hole shaft. Specifically, the input disc 41 is located at the shaft engaging portion 34d of the motor shaft 34, and the output disc 42 is located at the outer peripheral connecting portion 52b of the brake hub 52 of the brake mechanism 50. Even if the adjustment screw 36 is accidentally loosened too much to lower the upper limit torque transmission capacity, the friction plate 43 will not shift due to friction plate misalignment prevention mechanisms such as the outer peripheral rings 41c and 42c.

[0068] <About the effects> The electric chain hoist 10 configured as described above includes a load sheave 80 that winds up or down the load chain C1 by rotation, a motor 30 that provides a driving force to rotate the load sheave 80, a drive transmission shaft 60 that transmits the driving force from the motor 30 to the load sheave 80, a brake mechanism 50 that provides a braking force to stop the rotation of the drive transmission shaft 60, an input side disc 41 that is arranged on the end side (X2 side) of the motor shaft 34 of the motor 30 in the axial direction (X direction) of the motor shaft 34, an output side disc 42 that transmits the driving force to the drive transmission shaft 60, a friction clutch mechanism 40 that includes a friction plate 43 (friction member) that is sandwiched between the input side disc 41 and the output side disc 42 and applies a friction force thereto, and a disc spring body 45 (biasing member) that applies a biasing force to the friction plate 43 (friction member) against the input side disc 41 and the output side disc 42.

[0069] The brake mechanism 50 comprises a rotatable rotor 51d (brake rotor) and a brake hub 52 that is arranged at the radial center of the rotor 51d (brake rotor) and rotates coaxially with the rotor 51d (brake rotor) so as to transmit torque, and the drive transmission shaft 60 and the output side disc 42 are attached to the brake hub 52 so as not to rotate relative to each other.

[0070] In this configuration, the brake hub 52 of the brake mechanism 50 and the output side disc 42 of the friction clutch mechanism 40 are attached so as to be unable to rotate relative to each other, which reduces the number of parts compared to a configuration in which they are not fixed integrally, thereby improving ease of assembly and maintenance.

[0071] In this embodiment, the motor 30, the brake mechanism 50, and the friction clutch mechanism 40 constitute a drive unit 20, which is one unit.

[0072] In this configuration, the motor 30, the brake mechanism 50, and the friction clutch mechanism 40 are integrated to form the drive unit 20. This allows the drive unit 20 to be assembled as a single unit outside the housing 11. Furthermore, the friction surface of the friction clutch mechanism 40 can be worn in simply by supplying drive power to the motor 30. During maintenance of the electric chain hoist 10, the drive unit 20 can be removed as a single unit from the housing 11. This improves assembly within the housing 11 compared to a configuration in which the motor 30, the brake mechanism 50, and the friction clutch mechanism 40 are not integrated. Furthermore, the upper transmission torque limit of the friction clutch mechanism 40 can be replaced with a drive unit 20 already set. This allows the electric chain hoist 10 of this embodiment to be easily assembled and maintained.

[0073] In this embodiment, the motor 30 includes a motor frame 33 to which a stator 32 of the motor 30 is fixed, and the brake mechanism 50 includes a stator 51a (brake stator) facing a rotor 51d (brake rotor). The motor frame 33 and the stator 51a (brake stator) are fixed to each other, and this fixation forms an internal space SP1 between them. The input side disc 41, the output side disc 42, the friction plates 43 (friction members), and the disc spring bodies 45 (biasing members) that constitute the friction clutch mechanism 40 are arranged in the internal space SP1.

[0074] As shown in FIG. 2, the motor frame 33 and the stator 51a (brake stator) are fixed to each other in this manner, forming an internal space SP1. This allows the main components of the friction clutch mechanism 40 to be located in this internal space SP1, facilitating the integration of the drive unit 20 as a single unit. Furthermore, by utilizing the internal space SP1 to locate the main components of the friction clutch mechanism 40, the drive unit 20 can be made more compact. Furthermore, a bearing B2 is located in the side end wall 33b1 of the motor frame 33, supporting the motor shaft 34 to which the input-side disc 41 is fitted. The stator 51a is coaxially fixed from the side end wall 33b1 to the side end cylindrical portion 33b2. A bearing B3 supporting the brake hub 52 is located at the center of the stator 51a. Therefore, even though the stator 51a and the output-side disc 42 fitted to the brake hub 52 are fixed to different shafts, they can rotate coaxially without wobble.

[0075] In this embodiment, the motor shaft 34 is provided with a hollow portion 34a that is aligned with the axial direction (X direction) of the motor shaft 34, and a rod-shaped adjustment rod 35 is inserted into the hollow portion 34a. The friction clutch mechanism 40 is provided with a spring bearing member 44 that presses a disc spring body 45 (biasing member) toward the input-side disc 41, and a male thread portion 36a that screws into a female thread portion 34b provided in the hollow portion 34a is disposed at one end (X1 side) of the adjustment rod 35 in the axial direction (X direction). The spring bearing member 44 is disposed in contact with the other end (X2 side) of the adjustment rod 35 in the axial direction (X direction), and the male thread portion 36a is screwed into the spring bearing member 44 to press the spring bearing member 44 via the adjustment rod 35, thereby making it possible to adjust the biasing force of the disc spring body 45 (biasing member).

[0076] With this configuration, the adjustment rod 35 can be advanced or retreated in the axial direction (X direction) of the motor shaft 34 simply by adjusting the amount by which the adjustment screw 36, which partially protrudes from the hollow portion 34a, is screwed into the female thread portion 34b. This allows the amount by which the adjustment rod 35 presses the disc spring body 45 (biasing member) in the axial direction (X direction) via the spring bearing member 44 to be adjusted. This allows the friction torque of the friction clutch mechanism 40, based on the spring force of the disc spring body 45 (biasing member), to be adjusted from outside the motor frame 33. Furthermore, one end of the motor shaft 34 has a rotation prevention portion 34e, which easily prevents the motor shaft 34 from rotating when the adjustment screw 36 is screwed in. Furthermore, this configuration allows the friction clutch mechanism 40 and the brake mechanism 50 to be disposed adjacent to each other without complicating the structure, improving assembly and maintenance.

[0077] In the above-described invention, the motor 30 is a PM motor. Here, the electric chain hoist 10 of this embodiment is a battery-powered electric chain hoist equipped with a battery unit 12. Therefore, the motor 30 can be easily driven in situations where three-phase AC power is not available. Furthermore, because the motor 30 is a PM motor, it can be made more efficient and smaller than a three-phase induction motor or the like, and can also regenerate power. Furthermore, when a compact, highly efficient PM motor is used, the PM motor, the friction clutch mechanism 40, and the brake mechanism 50 can be arranged on one side of the load sheave 80, and the battery unit 12 equipped with a large-capacity battery can be arranged on the other side.

[0078] In addition, in the above-described embodiment, the motor 30 constituting the drive unit 20 is arranged on one side (X1 side) of the load sheave 80 in the axial direction (X direction) of the motor shaft 34, and the battery main body 12a (battery) that supplies power to the motor 30 is arranged on the other side (X2 side) of the load sheave 80 in the above-described axial direction (X direction).

[0079] By adopting such a configuration, a large-capacity battery can be mounted without disrupting the weight balance of the entire electric chain hoist 10, including the components inside the housing 11.

[0080] <Modification> Although one embodiment of the present invention has been described above, the present invention can be modified in other ways, which will be described below.

[0081] In the above-described embodiment, a configuration including one brake mechanism 50 has been described. However, if it is deemed that one brake mechanism 50 alone is insufficient from the standpoint of safety, a configuration including two brake mechanisms 50, as shown in FIG. 7, may be employed. In the configuration shown in FIG. 7, brake mechanism 50B is disposed on the other side (X2 side) of load sheave 80 in the axial direction (X direction), and this brake mechanism 50B brakes the rotation of drive transmission shaft 60. Therefore, in the configuration shown in FIG. 7, even if either brake mechanism 50, 50B loses its braking function, braking force can be obtained from the other brake mechanism, braking drive transmission shaft 60 and braking the rotation of load sheave 80.

[0082] Furthermore, in the above-described embodiment, the electric chain hoist 10 is battery-powered, but it may be configured so that power is supplied from a power source instead of being battery-powered. In that case, for example, in FIG. 2, a configuration may be adopted in which a contactor or the like is disposed in the portion corresponding to the battery section 12 (not shown). [Explanation of symbols]

[0083] 10...electric chain hoist, 11...housing, 11a...side portion, 11b...opening portion, 12...battery portion, 12a...battery body, 12b...case, 13...upper hook, 14...lower hook, 15...chain bucket, 20...drive unit, 30...motor, 31...rotor, 32...stator, 33...motor frame, 33a...cylindrical portion, 33b1...side end wall, 33b2...side end cylindrical portion, 34...motor shaft, 34a...hollow portion, 34b...female thread portion, 34d...shaft engagement portion, 35...adjusting rod, 36...adjusting screw, 36a...male thread portion, 37...nut, 40...friction clutch mechanism, 41...input side disc, 42...output side disc, 43...friction plate (friction member) , 44...spring receiving member, 45...disc spring body (corresponding to biasing member), 45a...disc spring, 50...brake mechanism, 51...electromagnetic brake portion, 51a...stator, 51b...armature, 51c...plate, 51d...rotor, 52...brake hub, 52a...inner peripheral connecting portion, 60...drive transmission shaft, 61...outer peripheral connecting portion, 62...pinion gear, 70...reduction mechanism, 71...driven gear member, 71a...large diameter gear, 71b...small diameter gear, 72...load gear, 80...load sheave, 81...center hole, 90...control circuit, 100...antenna, 110...operating device, 111...operating panel, 112...operating switch, B1, B2...bearing, C1...load chain, SP1...internal space

Claims

1. An electric chain hoist that hoists or lowers a load chain connected to a hook for hanging a load, a load sheave that rotates to wind up or down the load chain; a motor that provides a driving force to rotate the load sheave; a drive transmission shaft that transmits the driving force from the motor to the load sheave; a brake mechanism that applies a braking force to stop the rotation of the drive transmission shaft; a friction clutch mechanism including an input side disc arranged on an axial end side of a motor shaft of the motor, an output side disc that transmits driving force to the drive transmission shaft, a friction member that is sandwiched between the input side disc and the output side disc and applies a friction force thereto, and an urging member that applies a urging force to the input side disc and the output side disc by pressing the friction member against the input side disc and the output side disc; Equipped with the brake mechanism includes a rotatable brake rotor and a brake hub that is disposed at the radial center of the brake rotor and rotates coaxially with the brake rotor so as to be able to transmit torque; The drive transmission shaft and the output side disc are attached to the brake hub so as not to rotate relative to each other. An electric chain hoist characterized by:

2. The electric chain block according to claim 1, The motor, the brake mechanism, and the friction clutch mechanism constitute a single drive unit. An electric chain hoist characterized by:

3. The electric chain block according to claim 2, the motor includes a motor frame that fixes a stator of the motor; the brake mechanism includes a brake stator facing the brake rotor, the motor frame and the brake stator are fixed to each other, and an internal space is formed therebetween by the fixing; The input side disc, the output side disc, the friction member, and the biasing member that constitute the friction clutch mechanism are arranged in the internal space. An electric chain hoist characterized by:

4. The electric chain block according to claim 1, The motor shaft is provided with a hollow portion along the axial direction of the motor shaft, A rod-shaped adjustment rod is inserted into the hollow portion, The friction clutch mechanism is provided with a spring bearing member that presses the biasing member toward the input side disc, a male screw portion that is screwed into a female screw portion provided in the hollow portion is disposed on one end side of the axial direction of the adjustment rod, The spring bearing member is disposed in contact with the other end of the adjustment rod in the axial direction, The biasing force of the biasing member can be adjusted by pressing the spring bearing member via the adjustment rod by screwing in the male screw portion. An electric chain hoist characterized by:

5. The electric chain block according to claim 2, The motor is a PM motor. An electric chain hoist characterized by:

6. The electric chain block according to claim 3 or 5, On one side of the load sheave in the axial direction, A drive unit is configured as one unit. The drive unit or the motor is arranged, A battery that supplies power to the motor is disposed on the other side of the load sheave in the axial direction. An electric chain hoist characterized by:

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