Drum operator and electric chain hoist

Abstract

The present invention provides a cylinder operating device and an electric chain hoist, which can effectively prevent the occurrence of shaking of goods and stabilize the speed when the goods are lifted or lowered; the cylinder operating device (60) is a cylinder operating device (60) for operating the drive of an electric motor (40) that provides a driving force for winding and unwinding a load chain (C1), and comprises: a cylindrical member (64) in a cylindrical shape, a movable handle (70) that can slide axially relative to the cylindrical member (64), a detection unit (80) for detecting the sliding amount of the movable handle (70), a hook connecting rod (90) arranged inside the cylindrical member (64) and connected to a hook (200) for hanging goods, and a spring body (100) housed inside the cylindrical member (64) and applying a force to make the hook connecting rod (90) move upward.

Description

Technical Field

[0001] The present invention relates to a cylindrical operation device and an electric chain hoist. Background Art

[0002] For example, in an electric chain hoist, there is a cylindrical (cylindrical) operating device (hereinafter referred to as a "cylindrical operating device") that is operated by a portion held by an operator. In the cylinder operating device, the load chain is wound up and unwound by driving the motor, thereby enabling the cargo mounted on the lower hook to be raised or lowered. As such a cylinder operating device, for example, there is a structure shown in Patent Document 1.

[0003] Patent Document 1 discloses a structure and control for relieving the impact when a drum handling device of the type that lifts and lowers a load at a predetermined speed leaves the ground or falls to the ground.

[0004] [Prior art literature]

[0005] [Patent Literature]

[0006] Patent Document 1: Japanese Patent No. 5065724 Summary of the invention

[0007] (Problems to be solved by the invention)

[0008] However, unlike the drum operating device disclosed in Patent Document 1, which raises and lowers cargo at a predetermined speed, a drum operating device with fast response and stepless speed change is conceived to improve work efficiency. During the development of such a drum operating device, it was found that cargo swaying is a problem.

[0009] That is, if the handle, which is the operating part of the cylinder operating device, is held by the hand and the handle is slid upward relative to the cylindrical part, the motor is driven to rotate the load pulley, and the load chain is wound up, so that the cargo is lifted. At this time, the load chain between the load pulley and the hook is extended. After that, the cargo starts to rise, and the cylindrical part also rises with the rise of the cargo. During this rise, the cylindrical part starts to rise later than the handle held by the hand, and then rises faster than the winding speed, so the position of the handle relative to the cylindrical part reaches the initial position.

[0010] Furthermore, due to the inertia of the cargo and the contraction force of the extended load chain, the cargo and the tubular member rise relative to the handle, and the handle is located below the initial position relative to the tubular portion. Therefore, the motor rotates the load pulley in the direction of lowering the cargo against the operator's will.

[0011] Thus, in the setting that emphasizes responsiveness, the inertia of the cargo and the cylindrical portion during lifting and lowering and the relative position change with the handle cause the cargo to repeatedly rise and fall (cargo pitching), which is a phenomenon that is amplified and difficult to control. This cargo swaying becomes more noticeable in a cylindrical operating device that emphasizes operability that can change speed linearly and can change speed infinitesimally, even with a small amount of sliding.

[0012] In addition, the drum for winding the rope is cylindrical, but the meshing part of the load pulley for winding up the load chain is polygonal. During winding and unwinding, the load chain will have speed changes caused by the polygon effect (influence). The influence of this speed change is also transmitted to the cylindrical part, causing subtle changes in the relative position between the cylindrical part and the handle. As a result, the speed of the cargo is unstable when lifting and lowering, which amplifies the shaking of the cargo.

[0013] The present invention has been completed in view of the above situation, and its purpose is to provide a cylinder operating device and an electric chain hoist that can effectively prevent the shaking of goods in a high-speed, highly responsive and excellently operable electric chain hoist, can adjust the speed through subtle operations, and can stabilize the speed when the goods are lifted or lowered.

[0014] (Solutions to solve problems)

[0015] In order to solve the above-mentioned problems, according to a first aspect of the present invention, there is provided a drum operating device which operates the driving of a motor which applies a driving force to wind up and unwind a load chain, and the drum operating device has the following characteristics. The drum operating device comprises: a cylindrical member, a movable handle, a detection unit, a hook connecting rod, and a spring body, wherein the cylindrical member is provided in a cylindrical shape, the movable handle can slide in the axial direction relative to the cylindrical member, the detection unit detects the sliding amount of the movable handle, the hook connecting rod is arranged inside the cylindrical member and connected to a hook for hanging cargo, and the spring body is housed inside the cylindrical member and applies an upward force to the hook connecting rod.

[0016] Furthermore, another aspect of the present invention is preferably that a fixed handle that can be grasped by hand is installed in the tubular component at a position axially closer to the hook side than the movable handle so as to not move axially relative to the tubular component, and the spring body is accommodated inside the fixed handle.

[0017] In another aspect of the present invention, it is preferable that the detection means is a magnetic sensor that magnetically detects relative movement of the movable handle with respect to the tubular member.

[0018] Furthermore, in another aspect of the present invention, it is preferable that the spring body is configured in a state where a plurality of disc springs are stacked.

[0019] Furthermore, according to a second aspect of the present invention, an electric chain hoist is provided, which has the following characteristics: it has the cylinder operating device involved in each of the above inventions, and also has: a control unit that controls the driving speed of the motor to three or more steps or no step according to the sliding amount of the movable handle detected by the detection unit; a motor whose driving is controlled by the control unit; and a load pulley that is rotated by the motor and performs winding and unwinding of the load chain.

[0020] (Effects of the Invention)

[0021] According to the present invention, it is possible to provide a drum operating device and an electric chain hoist having excellent operability, which can effectively prevent the occurrence of shaking of cargo and stabilize the speed when the cargo is raised or lowered. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a side view showing the overall structure of an electric chain hoist according to one embodiment of the present invention.

[0023] Figure 2 Yes means Figure 1 , which shows the structure of the cylinder operating device of the electric chain hoist, and is a cross-sectional view showing a state viewed from the side.

[0024] Figure 3 Yes means Figure 2 A perspective view of the structure of a disc spring provided in the cylinder operating device shown in FIG.

[0025] Figure 4 The figures schematically show a situation in which cargo shakes in an electric chain hoist and a cylinder operating device in a stage before the electric chain hoist of the present embodiment is implemented, wherein (a) shows an initial state, (b) shows a state in which the movable handle is slid upward, (c) shows a state in which the neutral position is reached by the rise of the cargo and the cylindrical member, and (d) shows a state in which the movable handle is located below the cylindrical member by the rise of the cargo and the cylindrical member.

[0026] Figure 5 is with Figure 4 Similarly, the figures schematically show situations in which the cargo is swayed, wherein (a) shows a state in which the cargo and the tubular member are lowered to reach the neutral position, (b) shows a state in which the cargo and the tubular member are lowered and the movable handle is located above the tubular member, (c) shows a state in which the cargo and the tubular member are raised to reach the neutral position, and (d) shows a state in which the cargo and the tubular member are raised and the movable handle is located below the tubular member.

[0027] Figure 6The figures schematically show the situation of suppressing the shaking of the cargo in the electric chain hoist and the cylinder operating device of the present embodiment, wherein (a) shows the initial state, (b) shows the state in which the movable handle is slid upward, (c) shows the state in which the movable handle reaches the neutral position due to the rise of the cargo and the cylindrical part, and (d) is a figure showing the situation in which the cargo rises with a delay.

[0028] Figure 7 is with Figure 6 Similarly, the following diagrams schematically show the situation where the cargo is swaying, wherein (a) shows the state where the spring body is contracted due to the rise of the cargo and the tubular member, and (b) shows the length of the spring body and the Figure 6 (a) shows the same state, (c) shows the state where the spring body is extended, and (d) shows the state where the cargo is lifted and the spring body is contracted. DETAILED DESCRIPTION

[0029] Hereinafter, a cylindrical operation device 60 according to one embodiment of the present invention and an electric chain hoist 10 having the cylindrical operation device 60 will be described with reference to the accompanying drawings. In the following description, the Z direction refers to the axial direction of the cylindrical operation device 60 (the direction in which the load chain C1 is suspended), the Z1 side refers to the upper side, and the Z2 side refers to the lower side opposite thereto.

[0030] <About the overall structure of the electric chain hoist>

[0031] Figure 1 1 is a side view showing the overall structure of the electric chain hoist 10 having the cylinder operating device 60. Figure 1 As shown in the figure, the electric chain hoist 10 of this embodiment includes: an upper hook 20, a chain hoist body 30, a cylinder operating device 60, a load chain C1, and a lower hook 200. The chain hoist body 30 has a motor 40, and the load chain C1 can be rolled up and unwound by the drive of the motor 40. In addition, the electric chain hoist 10 also includes a chain bucket 50 for storing the load chain C1.

[0032] In addition, the electric chain hoist 10 is further provided with a control unit 45 for controlling the driving of the motor 40. The control unit 45 controls the driving of the motor 40 based on a detection signal from a detection sensor 80 described later. In addition, the control unit 45 can change the driving speed of the motor 40 steplessly (without step difference) according to the sliding amount of the movable handle 70 detected by the detection sensor 80 described later. However, the control unit 45 can also control the driving speed of the motor 40 to a predetermined step difference such as three or more steps.

[0033] In addition, the lower hook 200 (corresponding to the hook) is a part for hanging the cargo W, and in order to prevent the hung cargo W from falling off, a hook lock 202 that can rotate around the rotation axis 201 is also installed. In addition, the lower hook 200 can be a structural element of the cylinder operating device 60, or a component that is independent of the structural element of the cylinder operating device 60.

[0034] <About the structure of the cylinder operating device>

[0035] Figure 2 2 is a cross-sectional view showing the structure of the cylinder operating device 60 and showing a state viewed from the side. Figure 1 as well as Figure 2 As shown in , the electric chain hoist 10 is provided with a cylinder operating device 60, which is electrically connected to the chain hoist body 30 via a cable 61 (winding wire). In addition, the cylinder operating device 60 has a cylinder housing portion 62, and an upper shell 63, a cylindrical member 64, and a fixed handle 65 are provided in the cylinder housing portion 62. In addition, these upper shell 63, cylindrical member 64, and fixed handle 65 are components with strength capable of bearing the suspension of cargo W, for example, steel materials are used as materials.

[0036] The upper housing 63 is a portion located on the upper side (Z1 side) of the cylinder housing portion 62, and is also a portion in which electric wires and the like are stored. In addition, a switch (not shown) such as a power button of the cylinder operating device 60 is mounted on a predetermined portion of the outer wall surface of the upper housing 63, and a circuit board corresponding to the switch is stored inside the upper housing 63. A chain connection portion 63a is provided on the upper side (Z1 side) of the upper housing 63, and the chain connection portion 63a is connected to the load chain C1. In addition, the lower side (Z2 side) of the upper housing 63 is connected to the cylindrical member 64 by, for example, a threaded portion 63b.

[0037] The cylindrical member 64 is a tubular member located between the upper housing 63 and the fixed handle 65. The cylindrical member 64 is a straight tube having a constant diameter. Therefore, a movable handle 70 described later can be slid along the cylindrical member 64.

[0038] A fixed handle 65 is firmly attached to the lower side (Z2 side) of the tubular member 64 through a threaded portion 64b. The fixed handle 65 is also a tubular member like the tubular member 64, but unlike the above-mentioned tubular member 64, a lower bottom 65a that closes the opening of the lower end side (Z2 side) thereof is provided integrally with the outer peripheral portion 65b. Here, the lower bottom 65a is a portion that bears the load when the cargo W is hung on the lower hook 200, and is provided to be thicker than the outer peripheral portion 65b so as to have sufficient strength and guide the hook connecting rod 90. However, if the strength of the lower bottom 65a is sufficient, and if the outer periphery of the flange portion 92 and the inner periphery of the fixed handle 65 are used to guide the tilting of the hook connecting rod 90, the thickness may be provided to be thinner than the outer peripheral portion 65b, or may be provided to be of the same degree of thickness.

[0039] In addition, the lower bottom portion 65a may be configured as a separate body from the outer peripheral portion 65b and fixed to the outer peripheral portion 65b via screws or the like.

[0040] In addition, the outer peripheral portion 65b of the fixed handle 65 is not a straight tube with a constant diameter, but is set so that the diameter changes to the outer periphery (has concave and convex). The outer peripheral portion 65b is set to a concave and convex shape so that the operator's fingers are located in the concave part and the convex part is located between the fingers. In the following description, the part with the concave and convex shape is referred to as the gripping portion 65c. That is, the gripping portion 65c is a portion that the operator can grip with his hand.

[0041] In addition, the movable handle 70 is slidably mounted on the cylindrical member 64. The movable handle 70 is a portion that slides relative to the cylindrical member 64 or the fixed handle 65 when the operator presses it with his thumb or holds it with his hand. That is, the movable handle 70 is a portion that slides relative to the cylindrical member 64 or the fixed handle 65, and a switch operation can be performed by this sliding.

[0042] In order to enable such sliding, the movable handle 70 is provided with an insertion hole 70a, and the fixing screw 71 is inserted into the insertion hole 70a. In addition, the cylindrical member 64 is provided with a long hole 64a that is long in the axial direction (Z direction), and the fixing screw 71 is inserted into the long hole 64a. Therefore, the movable handle 70 can slide in the axial direction (Z direction) by a distance corresponding to the axial direction (Z direction) length of the long hole 64a.

[0043] In addition, a recessed portion 70b for the operator's fingertips to enter is provided on the outer peripheral side of the movable handle 70. By moving the finger with the fingertips positioned in the recessed portion 70b, the movable handle 70 can be slid well.

[0044] Here, the fixing screw 71 is screwed into the threaded hole 72a of the inner movable member 72. The inner movable member 72 is a member disposed inside the cylindrical member 64, and is a member that slides integrally with the movable handle 70 by being fixed by the fixing screw 71. In addition, there is a threaded hole 72a for screwing the fixing screw 71. In addition, a sensor movable portion 81 (magnetic element) of the detection sensor 80 described later is mounted on the inner movable member 72.

[0045] In addition, an upper biasing spring 73 for applying downward force to the inner movable member 72 is disposed at the upper portion of the inner movable member 72 in the inner cylinder portion of the cylindrical member 64. On the other hand, a lower biasing spring 74 for applying upward force to the inner movable member 72 is disposed at the lower portion of the inner movable member 72 in the inner cylinder portion of the cylindrical member 64. By the biasing forces of the upper biasing spring 73 and the lower biasing spring 74, when the operator does not operate the movable handle 70, the movable handle 70 and the inner movable member 72 are maintained in a neutral position.

[0046] In order to abut the lower end of the lower biasing spring 74, a spring support portion 75 is disposed in the inner tube portion of the tubular member 64 at a position below the inner movable member 72. On the other hand, the upper end of the upper biasing spring 73 is abutted by an upper flange portion (not shown) of the tubular member 64.

[0047] In addition, a detection sensor 80 (corresponding to the detection unit) is arranged on the upper side of the inner movable part 72. The detection sensor 80 has a sensor movable part 81 and a sensor fixed part 82. The detection sensor 80 is a magnetic sensor that magnetically detects the relative movement of the movable handle 70 relative to the cylindrical part 64. As such a magnetic sensor, a representative one is a Hall sensor. In the case where the detection sensor 80 is a Hall sensor, the sensor movable part 81 is, for example, a magnetic element, which is mounted on the upper end of the inner movable part 72. On the other hand, the sensor fixed part 82 is a detection circuit that uses the Hall effect to detect, for example, the contact or separation of the sensor movable part 81 as a magnetic element. The sensor fixed part 82 is mounted on the upper end side of the cylindrical part 64.

[0048] In addition, the sensor fixing portion 82 may be set as, for example, a magnetic element, and the sensor movable portion 81 may be set as, for example, a detection circuit. In addition, the detection sensor 80 is not limited to a Hall sensor. As a magnetic sensor other than the Hall sensor, for example, the detection sensor 80 may be a differential transformer using, for example, a coil, and an MR sensor using a magnetoresistive effect element may also be cited. However, the detection sensor 80 may also be a sensor other than a magnetic sensor such as an electrostatic capacitive sensor.

[0049] In addition, a hook connecting rod 90, a spring body 100, and a thrust bearing 110 are arranged in the inner cylinder of the fixed handle 65. The hook connecting rod 90 is a rod-shaped (shaft-shaped) member whose lower side protrudes downward through the shaft hole 65a1 formed in the lower bottom 65a. A threaded portion 91 is provided on the lower end side of the hook connecting rod 90, and the threaded portion 91 is screwed into the threaded hole 200a of the lower hook 200, thereby firmly connecting the two. In addition, a flange portion 92 with a larger diameter than other portions is provided on the upper end side of the hook connecting rod 90, and the flange portion 92 presses the spring body 100 from the upper side.

[0050] In addition, the spring body 100 is formed by stacking a plurality of disc springs 101. Figure 2 as well as Figure 3 As shown in , adjacent disc springs 101 are arranged in such a manner that their vertical directions are opposite to each other. As a result, when cargo W is hung on the lower hook 200 and the cargo W is raised or lowered, the lower hook 200 and the cargo W can be elastically swung (vibrated) in the vertical direction. Although the spring body 100 can suppress the pitch of the cylindrical housing portion 62 when it is soft (small spring constant), if it is too soft, the length of the cylindrical housing portion 62 needs to be extended to accommodate the spring body 100, but the operation becomes difficult. Therefore, it is preferable to select a spring body 100 with the same degree of deflection (expansion) as the load chain C1 and to accommodate it in the fixed handle 65.

[0051] In addition, the hook connecting rod 90 and the lower hook 200 are connected by the screw portion 91, but it is preferably configured so that the initial spring pressure of the disc spring 101 of the spring body 100 can be adjusted to a predetermined amount according to the tightening amount of the screw portion 91, for example, even if the cylindrical housing portion 62 is tilted under no load, the lower hook 200 does not rotate around the axis of the hook connecting rod 90 due to the influence of the self-weight of the lower hook 200. When the load of the cargo W is applied to the lower hook 200, the spring body 100 is bent, thereby releasing the contact between the upper end of the lower hook 200 and the lower surface of the lower bottom portion 65a of the fixed handle 65, and the thrust bearing 110 also functions, so that the lower hook 200 can be easily rotated.

[0052] If the spring constant of the load chain C1 in the use length is K1 and the spring constant of the spring body 100 is K2, K1 and K2 are set to be substantially the same. Even if the spring constant is set to this, the pitching of the cargo W when the cargo W is lifted or lowered is mainly absorbed by the expansion and contraction of the spring body 100. In addition, since the load chain C1 is wound up, the length of the unwinding becomes shorter and the spring constant becomes larger (changes according to the unwinding length), but it is preferable to determine the spring constant of the spring body 100 based on the load chain C1 in the length with high frequency of use.

[0053] In addition, the thrust bearing 110 is a bearing that abuts against the lower end side of the spring body 100. Due to the presence of the thrust bearing 110, the hook connecting rod 90, the spring body 100, and the lower hook 200 can be easily rotated relative to the fixed handle 65. The length of the fixed handle 65 is about the width of a human palm, and the spring body 100 is stored so as to fall within the length of the fixed handle 65. When the longest length of the load chain C1 is, for example, 3m, if a 150kg cargo W is hung, the load chain C1 is extended by, for example, about 6mm, and the spring body 100 is selected: when the cargo W is hung, for example, it is bent by about 5mm to 6mm.

[0054] <About the function>

[0055] The following describes the functions of the electric chain hoist 10 and the drum operating device 60 having the above-mentioned structure. First, the functions of the existing electric chain hoist 10A and the drum operating device 60A (parts related to the shaking of the cargo) are described. In addition, in the following description, the load chain C1 is described as a spring.

[0056] Figure 4 and Figure 5 1 is a diagram schematically showing a situation where the goods are shaken in the electric chain hoist 10A and the drum operating device 60A before the electric chain hoist 10 of the present embodiment is implemented. Figure 4 and Figure 5 In the figure, regarding the configuration related to the electric chain hoist 10A, the letter "A" is attached to the symbol.

[0057] like Figure 4 As shown in (a), in the initial state (pre-operation state) of the electric chain hoist 10A, the movable handle 70A is in a neutral position. At this time, since the motor 40 is not driven, the load pulley 41 does not rotate either.

[0058] From this state, Figure 4 As shown in (b), the operator holds the movable handle 70A and slides the movable handle 70A upward. Then, based on the detection signal from the detection sensor 80 corresponding to the amount of upward sliding of the movable handle 70A, the motor 40 is driven to rotate the load pulley 41 (forward rotation) to wind up the load chain C1. Figure 4 The state shown in (b) shows a state in which the load chain C1 is rolled up but the cargo W has not started to rise. Therefore, the load chain C1 is extended.

[0059] Then, if the load chain C1 is rolled up, Figure 4As shown in (c), the cargo W and the tubular member 64A also rise as the load chain C1 is rolled up and contracted. Here, the movable handle 70A is the part that the operator holds, and when the operator holds the handle continuously, the height position is almost unchanged. Figure 4 In the state shown in (c), the movable handle 70A reaches the neutral position (initial position) of the cylindrical member 64A. In addition, due to the rise of the cargo W, the cargo W generates upward inertia. Therefore, the cargo W wants to move further upward.

[0060] Then, if the cargo W and the tubular member 64A continue to rise, Figure 4 The state shown in (d). Figure 4 In (d), the movable handle 70A is located relatively downward relative to the tubular member 64A, and the load chain C1 is in a state of maximum contraction. Therefore, this time, based on the detection signal from the detection sensor 80 based on the sliding of the movable handle 70A toward the downward position relative to the tubular member 64A, the motor 40 is driven in the direction of unwinding the load chain C1. As a result, the load chain C1 begins to unwind with the rotation (reverse rotation) of the load pulley 41 against the operator's will.

[0061] Then, if the unwinding of the load chain C1 is continued, Figure 5 As shown in (a), the tubular member 64A descends together with the cargo W. Figure 5 As shown in (a), the movable handle 70A reaches the neutral position (initial position) of the tubular member 64A. At this time, due to the descent of the cargo W, the cargo W also generates downward inertia. Therefore, the cargo W wants to move further downward.

[0062] Then, if the cargo W and the tubular member 64A continue to descend, Figure 5 The state shown in (b). Figure 5 In (b), the movable handle 70A is located relatively above the cylindrical member 64A. In addition, the load chain C1 is also in an extended state. That is, it can be said that Figure 5 (b) Transfer to Figure 4 After that, the same state as (b) is reached. Figure 4 (c) the same Figure 5 The state transition of (c) is the same as that of Figure (4d). Figure 5 (d) State transition.

[0063] In this way, when the movable handle 70A is slid upward relative to the tubular member 64A in an attempt to raise the cargo W, the cargo W is lowered after being raised, and the movable handle 70A moves up and down relative to the tubular member 64A, thereby causing and amplifying the cargo shaking (pitch shaking of the cargo W) such as the repeated up and down movement of the cargo W. Therefore, it is impossible to perform fine speed adjustment, or to improve speed and responsiveness, especially responsiveness.

[0064] In contrast, in the electric chain hoist 10 and the drum operating device 60 of the present embodiment, the shaking of the cargo is effectively prevented. Figure 6 and Figure 7 , the role of the electric chain hoist 10 and the cylinder operating device 60 of this embodiment in preventing the goods from shaking will be described. In addition, the spring body 100 is a compression spring formed by overlapping the disc springs 101, but the spring body 100 can also be a tension spring. Figure 6 and Figure 7 , a tension spring is shown as the spring body 100, but the extension and compression of the spring body 100 formed by the tension spring are replaced by the compression and extension of the spring body 100 formed by the compression spring. When the spring body 100 formed by the tension spring is stretched or the spring body 100 formed by the compression spring is compressed, the lower hook 200 is displaced downward (moved away) relative to the cylindrical member 64, and when the spring body 100 formed by the tension spring is compressed or the spring body 100 formed by the compression spring is stretched, the lower hook 200 is displaced upward (moved closer) relative to the cylindrical member 64.

[0065] like Figure 6 As shown in (a), in the initial state (pre-operation state) of the electric chain hoist 10 of this embodiment, Figure 4 In (a), the movable handle 70 is in the neutral position. In addition, the spring body 100 is bent by the load of the cargo W and the lower hook 200, and the lower hook 200 is in a state of being located below the tubular member 64 by a predetermined amount.

[0066] From this Figure 6 The state shown in (a) is as follows: Figure 6 As shown in (b), the operator holds the movable handle 70 and slides the movable handle 70 upward. Then, based on the detection signal from the detection sensor 80 corresponding to the amount of upward sliding of the movable handle 70, the motor 40 is driven to rotate the load pulley 41 (forward rotation) to wind up the load chain C1. Figure 6 (b) shows the state immediately after the load chain C1 has just been rolled up.

[0067] Then, in Figure 6After the state (b) in the figure, the load chain C1 starts to be rolled up. Figure 6 The state shown in (b) is Figure 6 The state transition shown in (c) is shown in Figure 6 In the state shown in (c), the cargo W continues to rise at a speed at which the spring body 100 is deflected and stabilized. At this time, the movable handle 70 is operated by placing the movable handle 70 at a speed position desired by the operator relative to the tubular member 64.

[0068] In this Figure 6 After the state shown in (c), even if the operator returns the movable handle 70 to the neutral position, the upward force accumulated in the spring body 100 causes the cargo W to rise and become Figure 6 The state shown in (d) above does not cause the cylindrical member 64 to be displaced relative to the movable handle 70 held by the operator.

[0069] Then, if Figure 7 As shown in (a) , the spring body 100 further contracts, thereby preventing the upward movement of the cargo W from being transmitted to the tubular member 64 .

[0070] Moreover, in Figure 7 After (a), the contraction of the spring body 100 is released and the cargo W descends. Figure 7 As shown in (b), the length of the spring body 100 is Figure 6 At this time, due to the descent of the cargo W, downward inertia is generated in the cargo W. Therefore, the cargo W wants to move further downward.

[0071] Then, the cargo W and the tubular member 64 continue to descend, becoming Figure 7 The state shown in (c). Figure 7 In (c), the spring body 100 is extended. In addition, after the spring body 100 is extended, Figure 7 As shown in (d), the cargo W rises. After that, as described above, although the spring body 100 is repeatedly extended and contracted, its vibration gradually decays. By making the spring body 100 a compression spring composed of a plurality of disc springs 101, the decay is faster than that of a coil spring, so it is preferred.

[0072] Thus, in the electric chain hoist 10 and the cylinder operating device 60 of the present embodiment, after the cargo W is lifted, the spring body 100 is extended and retracted, thereby suppressing the movement of the cylindrical member 64 in the up-down direction. Therefore, even if a detection sensor that is sensitive to the sliding of the movable handle 70 is used, it is possible to eliminate the state in which the motor is driven to wind up and unwind against the operator's will due to the relative up-down movement of the movable handle 70 relative to the cylindrical member 64. Thus, the cargo can be prevented from shaking, and the lifting and lowering of the cargo W can be operated according to the operator's will.

[0073] <About the effect>

[0074] The cylinder operating device 60 structured as above comprises: a cylindrical part 64 configured to be cylindrical, a movable handle 70 capable of sliding axially relative to the cylindrical part 64, a detection sensor 80 (detection unit) for detecting the sliding amount of the movable handle 70, a hook connecting rod 90 arranged inside the cylindrical part 64 and connected to the lower hook 200 (hook) for hanging cargo W, and a spring body 100 housed inside the cylindrical part 64 and applying an upward force to the hook connecting rod 90.

[0075] By configuring in this way, even if the cargo W moves in the vertical direction with a delay after the movable handle 70 is slid relative to the tubular member 64, the vibration caused by the movement of the cargo W can be absorbed by the expansion and contraction of the spring body 100. Therefore, it is possible to suppress the tubular member 64 from moving in the vertical direction against the operator's will. Therefore, since it is possible to suppress the movable handle 70 that the operator holds and operates from moving up and down relative to the tubular member 64, it is possible to prevent the motor 40 from accidentally rotating forward and reversely. Therefore, it is possible to suppress the cargo from shaking.

[0076] In addition, the load pulley 41 is different from the cylindrical drum for winding the rope, and the meshing part with the load chain C1 is polygonal, so the speed change caused by the polygon effect (influence) occurs in the load chain C1, and the speed of the up and down movement of the cargo W becomes unstable. However, the spring body 100 is provided in the cylinder operation device 60 of the present embodiment. Therefore, by the expansion and contraction of the spring body 100, the speed change of the cargo W when the load pulley 41 rotates can be suppressed, so that the speed of the cargo W when it is raised and lowered can be stabilized. In addition, by appropriately combining the spring constant of the load chain C1 and the spring constant of the spring body 100, the resonance frequency can be changed to be inconsistent with the frequency generated by the rotation of the polygonal load pulley 41.

[0077] In addition, in the present embodiment, a fixed handle 65 that can be grasped by hand is installed in the cylindrical part 64 at a position axially closer to the lower hook 200 (hook) side than the movable handle 70 in a state that does not move axially relative to the cylindrical part 64, and the spring body 100 is accommodated and arranged inside the fixed handle 65.

[0078] Therefore, the operator can move the thumb while holding the fixed handle 65 with the hand other than the thumb, for example, while pressing the thumb against the movable handle 70, thereby performing an operation of moving the cargo W up and down. In this case, the fingers other than the thumb are located on the fixed handle 65, and the thumb is located on the movable handle 70. Therefore, even if the cylindrical member 64 moves up and down due to the up and down movement of the cargo W, the distance between the movable handle 70 and the fixed handle 65 can be maintained at a certain distance. Therefore, by driving the motor 40 by the unintentional operation of the movable handle 70, it is possible to more reliably prevent the cargo W from moving up and down (swaying of the cargo). In addition, although it is effective to prevent the cargo from shaking when the spring constant of the spring body 100 is reduced, the length of the spring body 100 is required to be able to maintain the load of the cargo W when the spring constant is reduced. By accommodating the spring body 100 in the fixed handle 65, it is easy to operate the cylinder operating device 60, and the interval between the movable handle 70 and the lower hook 200 is not increased, so that a small cylinder operating device can be realized.

[0079] In addition, in the present embodiment, the detection sensor 80 (detection unit) is preferably a magnetic sensor that magnetically detects the relative movement of the movable handle 70 with respect to the tubular member 64. When the detection sensor 80 (detection unit) is a magnetic sensor, even if the movable handle 70 is slightly slid, the sliding amount can be detected. Therefore, without sliding the movable handle 70 greatly, the speed can be finely adjusted by a small operation, so that the movement amount of the cargo W in the up and down direction can be accurately controlled.

[0080] In addition, in the present embodiment, the spring body 100 is formed in a state where a plurality of disc springs 101 are stacked. Therefore, the spring body 100 can be easily formed by simply stacking disc springs 101 of a number corresponding to a desired stroke amount (spring constant) inside the fixed handle 65. In addition, the spring body 100 in which a plurality of disc springs 101 are stacked has more attenuation during expansion and contraction than a coil spring, and is therefore preferred in preventing the pitching of the cargo W.

[0081] In addition, the electric chain hoist 10 of the present embodiment has the above-mentioned cylinder operating device 60, and is provided with a control unit 45, a motor 40 and a load pulley 41, wherein the control unit 45 controls the driving speed of the motor 40 to more than three steps or no steps according to the sliding amount of the movable handle 70 detected by the detection sensor 80 (detection unit), the driving of the motor 40 is controlled by the control unit 45, and the load pulley 41 is rotated by the motor 40 and the load chain C1 is wound up and unwound.

[0082] Therefore, the movable handle 70 can be suppressed from moving up and down relative to the cylindrical member 64, so that the motor 40 can be prevented from accidentally rotating forward and reversely. Therefore, the occurrence of shaking of the cargo can be suppressed.

[0083] Furthermore, by the expansion and contraction of the spring body 100, the speed fluctuation when the load pulley 41 rotates can be suppressed, and the speed when the cargo W is raised and lowered can be stabilized.

[0084] <Modification>

[0085] Although the embodiments of the present invention have been described above, the present invention can be modified in various other ways. These will be described below.

[0086] In the above embodiment, the spring body 100 is formed by stacking a plurality of disc springs 101. However, the spring body is not limited to this structure. For example, a coil spring may be used as the spring body.

[0087] In addition, in the above-mentioned embodiment, the lower hook 200 is connected to the hook connection rod 90. However, the lower hook 200 may not be connected to the hook connection rod 90. For example, a chain ring may be attached to the hook connection rod 90.

[0088] (Explanation of symbols)

[0089] 10…Electric chain hoist, 20…Upper hook, 30…Chain hoist body, 40…Motor, 41…Load pulley, 45…Control unit, 50…Chain bucket, 60…Drum operating device, 61…Cable, 62…Drum housing, 63…Upper housing, 63a…Chain connecting portion, 64…Cylinder-shaped member, 64a…Slotted hole, 65…Fixed handle, 65a…Lower bottom, 65a1…Axial hole, 65b…Outer periphery, 65c…Grip, 70…Movable handle, 70a…Through hole, 70b…Concave portion , 71…fixing screw, 72…inner movable component, 72a…threaded hole, 73…upper force spring, 74…lower force spring, 75…spring bracket part, 80…detection sensor (corresponding to the detection unit), 81…sensor movable part, 82…sensor fixing part, 90…hook connecting rod, 91…threaded part, 92…flange part, 100…spring body, 101…disc spring, 110…thrust bearing, 200…lower hook, 201…rotating shaft, 202…hook lock, C1…load chain.

Claims

1. A drum operating device that operates the drive of an electric motor that imparts a driving force for winding and unwinding a load chain, The drum operating device is characterized in that: It has: a tubular member, a movable handle, a detection unit, a hook connecting rod and a spring body, The tubular member is provided in a cylindrical shape and has a chain connection portion on its upper side. When cargo is hung, the load of the cargo acts on the tubular member. The movable handle can slide in the axial direction relative to the tubular member. The detection unit detects the sliding amount of the movable handle. The hook connecting rod is arranged inside the tubular member, can slide relative to the tubular member, and is connected to a hook for hanging the cargo. The spring body is accommodated in the tubular member and applies a force to move the hook connecting rod upward, and the spring body absorbs vertical vibrations of the hook and the cargo by elastically expanding and contracting. The spring body can suppress speed fluctuations caused by a polygonal effect of the load pulley, which occurs when the load chain is engaged with the polygonal load pulley.

2. The drum operating device according to claim 1, characterized in that: The tubular component includes a cylindrical component and a fixed handle, The fixed handle that can be grasped by hand is mounted on the cylindrical member at a position closer to the hook side than the movable handle in the axial direction in a state that the fixed handle does not move in the axial direction relative to the cylindrical member. The spring body is accommodated in the fixed handle.

3. The drum operating device according to claim 1, characterized in that: The detection unit is a magnetic sensor that magnetically detects relative movement of the movable handle with respect to the tubular member.

4. The drum operating device according to claim 2, characterized in that: The detection unit is a magnetic sensor that magnetically detects relative movement of the movable handle with respect to the tubular member.

5. The drum operating device according to any one of claims 1 to 4, characterized in that: The spring body is formed by overlapping a plurality of disc springs.

6. An electric chain hoist, characterized in that: A drum operating device according to any one of claims 1 to 5; In addition, it has: a control unit configured to control the driving speed of the motor to have three or more steps or no step according to the sliding amount of the movable handle detected by the detection unit; The motor is driven by the control unit; as well as The load pulley is rotated by the motor and winds up and unwinds the load chain.

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