Power transmission gear unit of wearable robot

Abstract

The present invention relates to a power transmission gear unit for a wearable robot capable of fixing a wire without consuming separate power when lifting or moving heavy objects. In addition, the present invention is a power transmission gear unit that is mounted on a wearable robot that provides auxiliary force for lifting or moving a heavy object using a wire connected to a handle, and transmits power from a motor to a pulley that winds or unwinds the wire, and comprises an input gear section having a worm gear that rotates by meshing in a direction perpendicular to a worm inserted and installed on the rotational shaft of the motor, and an input gear that rotates integrally on the same shaft as the worm gear. The input gear section prevents reverse rotation caused by the heavy object and fixes the wire based on the reduction ratio of the worm gear, thereby eliminating the need to mount a separate brake device or worry about power consumption, and can provide a more efficient braking function.

Description

Technology Field

[0001] The present invention relates to a power transmission gear unit for a wearable robot capable of fixing a wire without consuming separate power when lifting or moving heavy objects. Background Technology

[0003] Generally, tasks in industrial or agricultural environments that require essential human labor include not only repetitive strenuous work but also the work of moving heavy loads.

[0004] For example, musculoskeletal disorders, particularly shoulder and joint diseases, occur frequently because repetitive tasks are performed in poor posture, such as lifting arms to harvest crops or moving objects at high positions.

[0005] Wearable robot or wearable robot technology is being developed to facilitate work by being worn on the user's body in such a work environment and providing assistive power.

[0006] For example, looking at a use example of a conventional wearable robot illustrated in FIG. 1, the user can fix a handle connected to a wire to a heavy object while wearing the wearable robot (1), move the heavy object while receiving assistance through the wire, and at the destination where the heavy object is to be stacked, the user can stack the heavy object more easily by using a motor mounted on the wearable robot (1) to rotate a pulley and wind the wire.

[0007] However, if the wire of the wearable robot (1) comes loose during the process of lifting or moving a heavy object, the load of the heavy object may be applied to the user, and there is a risk of the user being injured as a result, so it is necessary to provide a brake device or brake function that can fix the wire.

[0008] However, when a brake device is installed in a conventional wearable robot (1), the design becomes complex and manufacturing costs increase, and maintenance costs may increase. Also, if a brake function is implemented using a motor, there is a problem that the usable time of the wearable robot is shortened due to power consumption.

[0009] Therefore, it is necessary to devise a method to secure the wire without consuming power and without installing a separate braking device.

[0010] Meanwhile, the technology forming the background of the present invention is disclosed in Registered Patent Publication No. 10-2580724, Registered Patent Publication No. 10-1490885, and Published Patent Publication No. 10-2023-0028988. Prior art literature

[0012] Registered Patent Publication No. 10-2580724 (Registered Sep. 15, 2023) Registered Patent Publication No. 10-1490885 (Registered Feb. 2, 2015) Published Patent Publication No. 10-2023-0028988 (Published Mar. 3, 2023) The problem to be solved

[0013] The present invention has been devised in consideration of the above-mentioned problems, and aims to provide a power transmission gear unit for a wearable robot that can receive auxiliary force from a wire by fixing the wire connected to the heavy object without a separate brake device or power consumption when lifting or moving the heavy object.

[0014] The objectives of the present invention are not limited to those mentioned above, and other unmentioned objectives will be clearly understood by those skilled in the art from the description below. means of solving the problem

[0016] The present invention, for achieving the above-mentioned purpose, provides a power transmission gear unit for a wearable robot that is mounted on a wire connected to a handle to provide an auxiliary force for lifting or moving a heavy object, and transmits power from a motor to a pulley that winds or unwinds the wire, comprising: an input gear unit having a worm gear that rotates by meshing in a direction perpendicular to a worm inserted and installed on the rotational shaft of the motor, and an input gear that rotates integrally on the same shaft as the worm gear; wherein the input gear unit prevents reverse rotation by the heavy object and fixes the wire based on the reduction ratio of the worm gear.

[0017] In a preferred embodiment, the input gear portion has a reduction ratio of the worm gear of 1:50 or higher.

[0018] In a preferred embodiment, the transmission gear section further comprises a first transmission gear that meshes with and rotates with the input gear, and a second transmission gear that is provided on the same axis as the first transmission gear and rotates integrally on the axis.

[0019] In a preferred embodiment, it further includes an output gear portion having an output gear that rotates by meshing with the second transmission gear, and the pulley connected on the same axis as the output gear.

[0020] In a preferred embodiment, the worm gear, the input gear, and the first transmission gear are divided into a first group with identical modules, and the second transmission gear and the output gear are divided into a second group with identical modules, and the modules of the second group are formed to be relatively larger than those of the first group. Effects of the invention

[0022] By means of the aforementioned problem-solving means, the present invention prevents reverse rotation caused by a heavy object due to the worm gear and fixes the wire, so there is no need to install a separate brake device or worry about power consumption, and has the effect of providing a more efficient braking function. Brief explanation of the drawing

[0024] FIG. 1 is a drawing showing an example of use of a conventional wearable robot. FIG. 2 is a perspective view of a power transmission gear unit of a wearable robot according to the present invention. FIG. 3 is a drawing showing the meshed state of a gear applied to a power transmission gear unit of a wearable robot according to the present invention. Figure 4 is a torque graph showing the load applied to the pulley of a wearable robot by a heavy object. FIG. 5 is an angular velocity graph for explaining the self-locking function of a power transmission gear unit of a wearable robot according to the present invention. Specific details for implementing the invention

[0025] In the following description, specific details of the invention are provided to provide an overall understanding of the invention, but it will be obvious to those skilled in the art that the invention can be easily practiced without these specific details and by variations thereof.

[0026] Hereinafter, preferred embodiments according to the present invention will be described in detail with reference to the attached FIGS. 2 to 5, focusing on the parts necessary to understand the operation and function according to the present invention.

[0028] FIG. 2 is a perspective view of a power transmission gear unit of a wearable robot according to the present invention, and FIG. 3 is a drawing showing the meshed state of a gear applied to the power transmission gear unit of a wearable robot according to the present invention.

[0029] Referring to FIGS. 2 and 3, a power transmission gear unit (100) of a wearable robot according to one embodiment of the present invention may be configured to include an input gear section (110), a transmission gear section (120), and an output gear section (133) (130).

[0030] The power transmission gear unit (100) of a wearable robot according to one embodiment of the present invention can be mounted on a wearable robot and can be positioned between a pulley (10) that winds or unwinds a wire and a motor (20) to transmit power (rotational force) of the motor (20) to the pulley (10).

[0031] Here, the aforementioned wearable robot can provide assistive force for lifting or moving heavy objects using a wire connected to a handle, and can prevent injury to the worker by supporting or assisting various postures of the worker when performing various tasks in industrial or agricultural environments, such as harvesting or transporting crops.

[0032] In addition, the aforementioned pulley (10) can rotate in a forward or reverse direction by the rotational force generated by the motor (20) to perform the operation of winding or unwinding a pair of wires connected to the handle with the same force and direction.

[0033] In addition, the aforementioned motor (20) can generate rotational force by receiving power, and a worm (25) connected to the input gear part (110) can be inserted and installed in the rotation shaft.

[0034] The input gear unit (110) is configured to include an input shaft (111), a worm gear (113), and an input gear (115). The input shaft (111) is positioned in a direction perpendicular to the rotation axis of the motor (20), and the worm gear (113) is installed on the input shaft (111) and meshes with the worm (25) in a direction perpendicular to it and rotates in a specific direction by the worm (25). The input gear (115) is installed spaced apart on the same axis as the worm gear (113). That is, the input gear (115) is provided on the input shaft (111) and rotates axially in conjunction with the worm gear (113).

[0035] In addition, the worm gear (113) can be formed with a gear tooth count of 30 and a tip diameter of 22.4 mm, and can be provided in the form of a helical gear, and by means of a self-locking function according to structural characteristics, reverse rotation by a heavy object is prevented so that the wire can be maintained in a fixed state.

[0036] Therefore, the handle of the wearable robot can be fixed to a heavy object, and when lifting or moving the heavy object, the wire connected to the handle can be fixed while providing a predetermined assistive force.

[0037] For this purpose, the worm gear (113) can be formed to have a reduction ratio of at least 1:50, and the worm (25) can be designed to have a friction coefficient and screw angle capable of self-locking.

[0038] Additionally, the input gear (115) can be formed with a gear tooth count of 14 and a tooth tip diameter of 11.2 mm, and can be formed in the shape of a spur gear, but is not limited thereto.

[0039] The above transmission gear unit (120) is configured to include a transmission shaft (121), a first transmission gear (123), and a second transmission gear (125). The transmission shaft (121) is installed parallel to the input shaft (111) at a predetermined distance apart, and the first transmission gear (123) is installed on the transmission shaft (121) and rotates by meshing with the input gear (115). The second transmission gear (125) is installed on the same axis as the first transmission gear (123) at a distance apart. That is, the second transmission gear (125) is provided on the transmission shaft (121) and rotates axially as a unit with the first transmission gear (123).

[0040] Additionally, the first transmission gear (123) may be formed with a gear tooth count of 42 and a tip diameter of 30.8 mm, and the second transmission gear (125) may be formed with a gear tooth count of 23 and a tip diameter of 25 mm, and both the first transmission gear (123) and the second transmission gear (125) may be formed in the form of spur gears, but are not limited thereto.

[0041] The output gear (133) section (130) is configured to include an output shaft (131) and an output gear (133), the output shaft (131) is installed parallel to the transmission shaft (121) at a predetermined distance and has a pulley (10) connected to one end, and the output gear (133) is installed on the output shaft (131) and rotates by meshing with the second transmission gear (125).

[0042] Additionally, the output gear (133) can be formed with a gear tooth count of 26 and a tip diameter of 28 mm, and can be formed in the shape of a spur gear, but is not limited thereto.

[0043] Meanwhile, the aforementioned worm gear (113), input gear (115), and first transmission gear (123) may be divided into a first group with the same module, and the second transmission gear (125) and output gear (133) may be divided into a second group with the same module.

[0044] In addition, the modules may be formed differently for each group, and preferably, the module of the second group may be formed relatively larger than that of the first group, for example, the module of the first group may be set to 0.7 and the module of the second group may be set to 1.

[0045] The power transmission gear unit (100) of a wearable robot according to one embodiment of the present invention is mounted on the wearable robot and transmits the rotational force generated from the motor (20) to the input gear unit (110), the transmission gear unit (120), and the output gear unit (133) (130), thereby enabling the pulley (10) connected to the output gear unit (133) (130) to rotate.

[0046] Hereinafter, a self-locking function performed by a power transmission gear unit (100) of a wearable robot according to an embodiment of the present invention will be described.

[0048] FIG. 4 is a torque graph showing the load applied to the pulley of a wearable robot by a heavy object, and FIG. 5 is an angular velocity graph to explain the self-locking function of the power transmission gear unit of a wearable robot according to the present invention.

[0049] First, referring to FIG. 4, when calculating the torque acting on the pulley (10) through the wire fixed to the heavy object, a torque of 6.86 Nm is applied to the pulley (10) with a diameter of 3.5 cm when lifting a heavy object of 20 kg. This indicates that such a torque of 6.86 Nm is applied to the power transmission gear unit (100) of the wearable robot according to the present invention for a certain period of time.

[0050] Referring to FIG. 5, when a torque of 6.86 Nm is applied to the power transmission gear unit (100) of the wearable robot according to the present invention so that the torque is transmitted to the worm (25) through the worm gear (113), the angular velocity measured from the rotation axis on which the worm (25) is installed is shown, and it can be seen that a change in angular velocity occurs only during a short time of 0.1 seconds or less when the worm (25) and the worm gear (113) mesh with each other, and thereafter no change in angular velocity occurs and the system maintains a nearly stationary state.

[0051] That is, since reverse rotation caused by a heavy object is prevented and the wire is fixed by the self-locking function performed by the power transmission gear unit (100) of the wearable robot according to one embodiment of the present invention, there is no need to install a separate brake device or worry about power consumption, and a more efficient braking function can be provided.

[0052] Although preferred embodiments of the present invention have been described illustratively above, the scope of the present invention is not limited to such specific embodiments and can be appropriately modified within the scope described in the claims. Explanation of the symbols

[0054] 100: Power transmission gear unit of a wearable robot 110: Input gear section 111: Input shaft 113: Worm gear 115: Input gear 120: Transmission gear section 121: Transmission shaft 123: 1st transmission gear 125: 2nd transmission gear 130: Output gear section 131: Output shaft 133 : Output gear

Claims

Claim 1 A power transmission gear unit is mounted on a wearable robot that provides auxiliary force for lifting or moving a heavy object using a wire connected to a handle, and transmits power from a motor to a pulley that winds or unwinds the wire, comprising: an input gear section having a worm gear that rotates by meshing in a direction perpendicular to a worm inserted and installed on the rotational shaft of the motor, and an input gear provided on the same axis as the worm gear and rotating integrally on the axis; a transmission gear section having a first transmission gear that rotates by meshing with the input gear, and a second transmission gear provided on the same axis as the first transmission gear and rotating integrally on the axis; and an output gear section having an output gear that rotates by meshing with the second transmission gear, wherein the pulley is connected on the same axis as the output gear, wherein the input gear section prevents reverse rotation caused by the heavy object and fixes the wire based on the reduction ratio of the worm gear, and the worm gear, the input gear, and the first transmission gear are divided into a first group with identical modules, and the second transmission gear and the output A power transmission gear unit of a wearable robot, characterized in that the gear is divided into a second group of identical modules, and the modules of the second group are formed to be relatively larger than those of the first group. Claim 2 A power transmission gear unit of a wearable robot according to claim 1, wherein the input gear part is characterized in that the reduction ratio of the worm gear is 1:50 or higher. Claim 3 delete Claim 4 delete Claim 5 delete

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