Overload detection device and water gate opening / closing facility comprising the same

Abstract

To provide an overload detection device in which a deflection amount of a spring is proportional to a rotation angle of a rotary member, and a water gate opening / closing facility comprising the same.SOLUTION: An overload detection device 10 provided on a power transmission path for transmitting a rotational force of a motor to an external mechanism, comprises: a rotary member 12 that has teeth 26 formed along an outer edge of an imaginary circle, and rotates when a load is applied to the external mechanism, causing the teeth 26 to move along the outer edge of the imaginary circle; a movable member 13 that has a locking part 39, which engages with the teeth 26 and is provided linearly, and moves linearly along the locking part 39 when a force is applied from the moving teeth 26; a spring member 14 that bends in accordance with the movement of the movable member 13, and applies an elastic force to the movable member 13 in an opposite direction to the movement direction of the movable member 13; and detection means that detects the occurrence of an overload in the external mechanism based on a movement distance of the movable member 13. The locking part 39 is provided along a tangent of the imaginary circle.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to an overload detection device that detects an overload and a floodgate opening and closing facility equipped with the same. [Background technology]

[0002] In a watergate opening and closing facility that opens and closes a waterway by raising and lowering a gate body through the operation of a motor, if a load (hereinafter referred to as "overload") greater than a predetermined level occurs on the watergate opening and closing facility while the gate body is rising or falling, an overload detection device detects the occurrence of the overload and stops the operation of the motor to prevent damage to various components, etc. A conventional overload detection device, a specific example of which is disclosed in Cited Document 1, has a rotatable rotating member (swinging arm 7) provided between an input section (input sun gear 4) to which the rotational force of the motor is applied, and an output section (output sun gear 5) that outputs the rotational force toward a member, etc., that is moving the gate body upward.

[0003] The overload detection device is designed so that when a load occurs beyond the output section, the rotating member rotates against the elastic force of the springs (compression coil springs 25, 26), linearly moving the movable member (spring seats 22, 23). As the load occurring beyond the output section increases, the force applied from the rotating member to the spring via the movable member increases, and the rotation angle of the rotating member increases. In contrast, the force applied from the spring to the rotating member via the movable member increases with the increase in the amount of spring deflection (the amount of contraction in the case of a coil spring) due to the increase in the rotation angle of the rotating member.

[0004] Here, the detection means (limit switch 27) provided in the overload detection device detects the occurrence of an overload beyond the output part based on the amount of deflection of the spring that flexes with the rotation of the rotating member (actually, the moving distance of the movable member equal to the amount of deflection of the spring) reaching a predetermined amount. Therefore, in order to enable the overload detection device to detect the occurrence of an overload, it is necessary to find the amount of deflection of the spring when the load occurring beyond the output part reaches a predetermined size. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Jitszen No. 56-062457 Summary of the Invention [Problem to be solved by the invention]

[0006] However, in the overload detection device described in the cited document 1, the position of the point of application where the rotating member applies force to the spring via the movable member moves with the rotation of the rotating member, and the distance from the rotation center of the rotating member to the point of application changes. In other words, the amount of deflection of the spring is not proportional to the rotation angle of the rotating member. Therefore, in order to calculate the amount of spring deflection when the load generated beyond the output part reaches a certain level, a formula that takes into account the change in the distance from the center of rotation of the rotating member to the point of application is required, which is not easy to derive. Furthermore, this leads to a problem of low accuracy in overload detection.

[0007] The present invention has been made in consideration of the above circumstances, and has an object to provide an overload detection device in which the amount of spring deflection is proportional to the rotation angle of a rotating member, and a floodgate opening and closing facility equipped with the same. [Means for solving the problem]

[0008] An overload detection device according to a first invention which meets the above-mentioned objective is an overload detection device provided on a power transmission path which transmits the rotational force of a motor to an external mechanism, and comprises: a rotating member having teeth formed along the outer edge of an imaginary circle, which rotates when a load is applied to the external mechanism, so that the teeth move along the outer edge of the imaginary circle; a movable member having a linearly-arranged locking portion which engages with the teeth, and which moves linearly along the locking portion when force is applied from the moving teeth; a spring member which bends with the movement of the movable member and applies an elastic force to the movable member in a direction opposite to the movement direction of the movable member; and detection means which detects the occurrence of an overload in the external mechanism based on the movement distance of the movable member, and the locking portion is provided along a tangent to the imaginary circle.

[0009] A second invention relating to a floodgate opening and closing equipment that meets the above-mentioned objective is an overload detection device provided on a power transmission path that transmits the rotational force of a motor to a gate body, and in which the gate body is moved or rotated by operating the motor to open and close a floodgate, the overload detection device comprises a rotating member having teeth formed along the outer edge of a virtual circle, which rotates when a load is applied to the external mechanism, so that the teeth move along the outer edge of the virtual circle, a movable member having a linearly arranged locking portion that engages with the teeth and moves linearly along the locking portion when force is applied from the moving teeth, a spring member that bends as the movable member moves and applies an elastic force to the movable member in the opposite direction to the movement direction of the movable member, and a detection means for detecting an overload in the external mechanism based on the movement distance of the movable member, and the locking portion is provided along a tangent to the virtual circle. Effect of the Invention

[0010] The overload detection device of the first invention comprises a rotating member having teeth formed along the outer edge of an imaginary circle, and which rotates when a load is applied to the external mechanism, causing the teeth to move along the outer edge of the imaginary circle; a movable member having a linear engagement portion that engages with the teeth, and which moves linearly along the engagement portion when force is applied from the moving teeth; a spring member that deflects as the movable member moves, applying an elastic force to the movable member in the opposite direction to the movement direction of the movable member; and detection means for detecting an overload in the external mechanism based on the distance moved by the movable member, wherein the engagement portion is arranged along a tangent to the imaginary circle, and the amount of deflection of the spring is proportional to the rotation angle of the rotating member.

[0011] The second invention relates to a floodgate opening and closing equipment, and the overload detection device comprises a rotating member having teeth formed along the outer edge of a virtual circle and rotating when a load is applied to the external mechanism, so that the teeth move along the outer edge of the virtual circle; a movable member having a linear engagement portion that engages with the teeth and moves linearly along the engagement portion when force is applied from the moving teeth; a spring member that deflects as the movable member moves and applies an elastic force to the movable member in the opposite direction to the movement direction of the movable member; and detection means for detecting an overload in the external mechanism based on the distance moved by the movable member, and since the engagement portion is arranged along a tangent to the virtual circle, the amount of deflection of the spring is proportional to the rotation angle of the rotating member. [Brief description of the drawings]

[0012] [Figure 1] 1 is an explanatory diagram of an overload detection device according to an embodiment of the present invention; [Diagram 2] FIG. [Diagram 3] FIG. 2 is a block diagram showing the connection of a control means of the overload detection device. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Next, with reference to the attached drawings, an embodiment of the present invention will be described for understanding the present invention. 1 to 3, an overload detection device 10 according to an embodiment of the present invention is a device provided on a power transmission path that transmits the rotational force of a motor 11 to an external mechanism (not shown), and includes a rotating member 12 that rotates when a load is applied to the external mechanism, a movable member 13 that moves linearly with the rotation of the rotating member 12, a spring member 14 that applies an elastic force (restoring force) to the movable member 13 that is generated by bending with the movement of the movable member 13, and a detection means 15 that detects the occurrence of an overload in the external mechanism based on the moving distance of the movable member 13. These will be described in detail below.

[0014] 1 and 2, the overload detection device 10 comprises a gear 17 to which the rotational force of the motor 11 is applied via an input shaft 16, a sun gear 19 rotatably attached to a sun shaft 18 and meshing with the gear 17, and a planetary gear 21 rotatably attached to a planetary shaft 20. The gear 17 is fixed at its center to the input shaft 16, the sun gear 19 is rotatably attached to the sun shaft 18 via a bearing 22, and the gear 21 is keyed to the planetary shaft 20.

[0015] The input shaft 16, sun shaft 18 and planetary shaft 20 are arranged in parallel, and the gear 17, sun gear 19 and planetary gear 21 are arranged on the same plane. Note that in Figures 1 and 2, the positions of the input shaft 16, gear 17, output shaft 31 and gear 32 (described later) are depicted differently in Figures 1 and 2, but this is to make it easier to understand the meshing of the gears from the drawings, and in reality, they are arranged as shown in Figure 1.

[0016] Moreover, both ends of the sun shaft 18 are fitted and fixed in the supports 24 and 25, respectively. Therefore, in this embodiment, the axial center position of the sun shaft 18 is fixed. In contrast, the axial center position of the planetary shaft 20 is not fixed and is movable. The rotating member 12 is plate-like and formed in a sector shape when viewed along the axis of the sun shaft 18. The rotating member 12 has a tooth portion 26 made up of a plurality of teeth in a circular arc region on the front side (the entire circular arc region in this embodiment).

[0017] The sun shaft 18 penetrates the base side of the rotating member 12, and the rotating member 12 is rotatable around the axis of the sun shaft 18. The toothed portion 26 (the plurality of teeth of the toothed portion 26) is formed along the outer edge of a virtual circle (hereinafter referred to as "virtual circle T") centered on the rotation center of the rotating member 12 (axis of the sun shaft 18). The planetary shaft 20, to which the planetary gear 21 is keyed at one end, has a center portion (a position having a distance from the rotation center of the rotating member 12) penetrating the tip side of the rotating member 12, and the other end inserted into the center of the planetary gear 28. In this embodiment, the rotating member 12 is rotatably attached to the planetary shaft 20 via a bearing 27, and the planetary gear 28 is keyed to the planetary shaft 20.

[0018] A sun gear 29 meshing with a planetary gear 28 is rotatably attached to the sun shaft 18 via a bearing 30. A gear 32 meshing with the sun gear 29 is fixed to an output shaft 31 that transmits a rotational force to an external mechanism. In this embodiment, the respective axial center positions of the input shaft 16 and the output shaft 31 are fixed.

[0019] As shown in FIG. 1, the planetary gear 28, the sun gear 29 and the gear 32 are arranged on the opposite side of the planetary gear 21, the sun gear 19 and the gear 17 in the axial direction of the sun shaft 18 with the rotating member 12 as the reference. The planetary shaft 20 does not have a fixed axial position, and the planetary gears 21, 28 are meshed with the sun gears 19, 29, respectively. Therefore, the planetary gears 21, 28 can revolve around the sun gears 19, 29 together with the planetary shaft 20 while rotating around the planetary shaft 20, and the rotating member 12 rotates around the axial center of the sun shaft 18 as the planetary gears 21, 28 and the planetary shaft 20 revolve (move) around the sun gears 19, 29.

[0020] In this embodiment, the movable member 13 is rod-shaped as shown in Figures 1 and 2, and is rotatably supported by bearings 35 fixed to the support 34 and bearings 37, 38 attached to a support 36 arranged at a position some distance from the support 34 (in this embodiment, to the left of the support 34), and is arranged so as to form an angle of 90 degrees with respect to the sun axis 18 and the planetary axis 20.

[0021] Bearing 37 is disposed to the left of bearing 38 with a gap therebetween. In this embodiment, spring member 14 is a coil spring, and is attached to movable member 13 with its left end in contact with bearing 37 and its right end in contact with bearing 38. The spring member 14 is disposed so that its axis is aligned with the axis of movable member 13.

[0022] While the bearing 35 is fixed to the support 34, the bearings 37, 38 are movable left and right relative to the support 36. The support 36 is provided with a left limit position where the bearing 37 can move left and a right limit position where the bearing 38 can move right. The movable member 13 is attached to the bearings 35, 37, 38 so as to be movable left and right (towards one side and the other side in the axial direction of the movable member 13) relative to the supports 34, 36.

[0023] The bearing 37 moves left and right together with the movable member 13 in an area to the right of the left limit position, and the bearing 38 moves left and right together with the movable member 13 in an area to the left of the right limit position. With the movable member 13 in the standard position, the bearing 37 is located at the left limit position, and the bearing 38 is located at the right limit position. As shown in FIG. 2, the movable member 13 has a locking portion 39 that engages with the teeth portion 26 of the rotating member 12 between a portion supported by bearing 38 and a portion supported by bearing 35, and the tip end of an arm 40, the base end of which is rotatably connected to the detection means 15, is hooked between the locking portion 39 and the portion supported by bearing 35.

[0024] In this embodiment, the movable member 13 is in the shape of a round bar (cylinder) and is disposed along a tangent line (hereinafter referred to as "tangent line S") of the imaginary circle T. The locking portion 39 is formed of a plurality of disk-shaped protruding pieces formed on the movable member 13 at equal pitches in the axial direction of the movable member 13, and the locking portion 39 is provided along the tangent line S as a whole (the plurality of protruding pieces constituting the locking portion 39 are disposed along the tangent line S).

[0025] The position of the rotating member 12 when the movable member 13 is disposed at the standard position is taken as the standard position of the rotating member 12. When the rotating member 12 rotates clockwise from the standard position around the axis of the sun shaft 18, the movable member 13 is given a force from the teeth portion 26 moving clockwise, and moves linearly to the right together with the bearing 37 along the tangent line S (locking portion 39). As a result, the bearing 37 moving to the right contracts the spring member 14, and the contracted spring member 14 applies a leftward force to the movable member 13 via the bearing 37, and the movable member 13 applies a counterclockwise force to the rotating member 12.

[0026] On the other hand, when the rotating member 12 rotates counterclockwise from the standard position around the axis of the sun shaft 18, the movable member 13 is given a force from the teeth portion 26 moving counterclockwise, and moves linearly to the left together with the bearing 38 along the tangent line S (locking portion 39). As a result, the bearing 38 moving to the left contracts the spring member 14, and the contracted spring member 14 applies a rightward force to the movable member 13 via the bearing 38, and the movable member 13 applies a clockwise force to the rotating member 12. Therefore, the spring member 14 bends as the movable member 13 moves, and applies an elastic force to the movable member 13 in the opposite direction to the moving direction of the movable member 13, and the rotating member 12 rotates against the elastic force of the spring member 14 when rotating clockwise or counterclockwise.

[0027] In this embodiment, the tooth portion 26 is arranged along the outer edge of the imaginary circle T, and the locking portion 39 is arranged along the tangent line S, so that the multiple protruding pieces of the locking portion 39 and the multiple teeth of the tooth portion 26 can stably mesh with each other regardless of the rotation angle of the movable member 13. A movable member having teeth provided along the outer edge of a virtual circle whose center is different from the center of rotation of the movable member may be used, in which case the locking portion of the movable member is provided along a tangent to the virtual circle, and the overload detection device may be designed so that the movable member moves along the tangent. Also, a movable member made of a rack gear may be used instead of the movable member 13, in which case the locking portion is formed by multiple teeth of the rack gear.

[0028] The arm 40 rotates clockwise or counterclockwise as the movable member 13 moves left or right. In this embodiment, the detection means 15 is a limit switch, and as shown in Fig. 3, is connected to a control means 41 that controls the operation of the motor. The detection means 15 can detect the direction and distance of movement of the movable member 13 based on the rotation of the arm 40, and when it detects that the movable member 13 has moved to a preset position, it outputs a predetermined signal to the control means 41. The control means 41 receives the signal output from the movable member 13 and performs control such as stopping the motor 11 during operation.

[0029] In this embodiment, the overload detection device 10 is a device provided in a water gate opening and closing facility that opens and closes a water gate by raising and lowering (one example of movement) a gate body by operation of a motor 11, and the external mechanism is mainly composed of the gate body and a support member (such as a chain or a pin rack) that supports the gate body. When the gate body is raised or lowered by operation of the motor 11 (and also when the gate body is raised or lowered by manually operating a manual handle, if there is one), a load is generated in the external mechanism.

[0030] In this embodiment, when a load is applied to the external mechanism, the rotating member 12 rotates (spins) clockwise from the standard position around the axis of the sun shaft 18, causing the tooth portion 26 to move clockwise along the outer edge of the imaginary circle T, and the movable member 13 to move rightward from the standard position along the tangent line S. At this time, the sun gears 19, 29 rotate around the sun shaft 18, and the planetary gears 21, 28 revolve clockwise around the sun gears 19, 29. Therefore, the operation of the motor 11 causes the sun gears 19, 29 to rotate around the sun shaft 18.

[0031] When an obstacle comes into contact with the door body during ascent, and a load of a predetermined magnitude or more is applied to the external mechanism, that is, an overload occurs, the movable member 13 moves a predetermined distance to the right from the standard position. The detection means 15 detects the movement of the movable member 13 and detects that an overload has occurred in the external mechanism, and the control means 41 detects the detection of the overload by the detection means 15 and stops the operation of the motor 11.

[0032] In this embodiment, the distance from the center of rotation of the rotating member 12 to the point of application (the position where the teeth 26 of the rotating member 12 and the locking portion 39 of the movable member 13 mesh) at which the rotating member 12 applies force to the movable member 13 does not substantially change with the rotation of the rotating member 12. In other words, the amount of deflection of the spring member 14 is substantially proportional to the rotation angle of the rotating member 12. Therefore, it is easy to derive the amount of deflection of the spring when an overload occurs in an external mechanism. Furthermore, the accuracy of overload detection is higher than that of an overload detection device in which the amount of deflection of the spring member is not proportional to the rotation angle of the rotating member.

[0033] In addition, in Figures 1 and 2, the planetary gears 21, 28 and the rotating member 12, etc. are shown as being supported mainly by the sun gears 19, 29 and the movable member 13 only, but in reality, it goes without saying that a known guide mechanism is provided to limit the movable range of the movable member 13 so that the teeth portion 26 of the rotating member 12 and the engagement portion 39 of the movable member 13 do not disengage from each other.

[0034] In addition, a floodgate opening and closing equipment is provided with an overload detection device 10 and opens and closes a floodgate by moving a gate body by operating a motor, the overload detection device 10 comprising a rotating member 12 having teeth 26 formed along the outer edge of an imaginary circle T and rotating when a load is applied to the external mechanism, so that the teeth 26 moves along the outer edge of the imaginary circle T, a movable member 13 having a linearly arranged locking portion 39 that engages with the teeth 26 and moves linearly along the locking portion 39 when force is applied from the moving teeth 26, a spring member 14 that bends as the movable member 13 moves and applies an elastic force to the movable member 13 in the opposite direction to the movement direction of the movable member 13, and a detection means 15 that detects an overload occurring in the external mechanism based on the movement distance of the movable member 13, and the locking portion 39 is arranged along a tangent S of the imaginary circle T.

[0035] Although the embodiment of the present invention has been described above, the present invention is not limited to the above-mentioned embodiment, and all changes in conditions that do not depart from the gist of the present invention are within the scope of application of the present invention. For example, a water gate opening and closing system equipped with an overload detection device may be a system that opens and closes a water gate by rotating a door body. Furthermore, the overload detection device does not have to be provided in the water gate opening and closing equipment. For example, the overload detection device may be provided in equipment for opening and closing land gates or equipment for lifting heavy objects.

[0036] Furthermore, the rotating member does not have to be sector-shaped, but may be, for example, semicircular or circular. Also, the rotating member does not have to be plate-shaped. It is not necessary to provide two sun gears and two planetary gears. For example, there may be only one sun gear and one planetary gear. [Explanation of symbols]

[0037] 10: overload detection device, 11: motor, 12: rotating member, 13: movable member, 14: spring member, 15: detection means, 16: input shaft, 17: gear, 18: sun shaft, 19: sun gear, 20: planet shaft, 21: planet gear, 22: bearing, 24, 25: support, 26: teeth portion, 27: bearing, 28: planet gear, 29: sun gear, 30: bearing, 31: output shaft, 32: gear, 34: support, 35: bearing, 36: support, 37, 38: bearing, 39: engaging portion, 40: arm, 41: control means

Claims

1. An overload detection device provided on a power transmission path that transmits the rotational force of a motor to an external mechanism, a rotating member having teeth formed along an outer edge of an imaginary circle, the rotating member rotating when a load is applied to the external mechanism, the teeth moving along the outer edge of the imaginary circle; a movable member having a locking portion that is linearly arranged to mesh with the toothed portion, the movable member being moved linearly along the locking portion when a force is applied from the moving toothed portion; a spring member that bends with the movement of the movable member to apply an elastic force to the movable member in a direction opposite to the direction of movement of the movable member; a detection means for detecting an occurrence of an overload in the external mechanism based on a moving distance of the movable member, An overload detection device, characterized in that the engaging portion is provided along a tangent to the imaginary circle.

2. 2. The overload detection device according to claim 1, further comprising: a sun gear that rotates about a sun axis, the axis of which is fixed, due to operation of the motor; and a planetary gear that meshes with the sun gear and revolves around the sun gear together with the planetary shaft while rotating about its own axis due to the rotation of the sun gear, wherein the planetary shaft penetrates the rotating member at a position having a distance to the center of rotation of the rotating member, and the rotating member rotates as the planetary shaft moves around the sun gear.

3. 3. The overload detection device according to claim 1 or 2, wherein the overload detection device is provided in a gate opening and closing equipment which opens and closes a gate by moving or rotating a door body, and the external mechanism is configured to have the door body and a support member which supports the door body.

4. In a water gate opening and closing system, an overload detection device is provided on a power transmission path that transmits the rotational force of a motor to a gate body, and the gate body is moved or rotated by the operation of the motor to open or close a water gate, The overload detection device comprises a rotating member having teeth formed along the outer edge of a virtual circle and rotating when a load is applied to the external mechanism, so that the teeth move along the outer edge of the virtual circle; a movable member having a linearly arranged locking portion that engages with the teeth and moves linearly along the locking portion when force is applied from the moving teeth; a spring member that bends with the movement of the movable member and applies an elastic force to the movable member in the opposite direction to the movement direction of the movable member; and detection means for detecting an overload in the external mechanism based on the distance moved by the movable member, wherein the locking portion is arranged along a tangent to the virtual circle.

5. In the floodgate opening and closing equipment described in claim 4, the overload detection device comprises a sun gear that rotates around a sun axis whose axis position is fixed by operation of the motor, and a planetary gear that meshes with the sun gear and revolves around the sun gear together with the planetary shaft while rotating around the planetary shaft by the rotation of the sun gear, the planetary shaft penetrates the rotating member at a position having a distance to the rotation center of the rotating member, and the rotating member rotates as the planetary shaft moves around the sun gear.

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