JP2015039414A - Back muscle motion assisting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a back muscle motion assisting device capable of reliably assisting a motion of user's back muscle when the user lifts up a heavy object and allowing the user to walk while assisting the back muscle, thereby facilitating conveyance work of heavy objects.SOLUTION: A back muscle motion assisting device includes: a shoulder member 12 to be attached to the back of an operator 11; and a fixed link 28 to be attached along the back of the operator 11 in a vertical direction. The back muscle motion assisting device also includes: a lumbar member 42 attached in the middle of the fixed link 28 for contacting the lumbar of the operator 11; and a belt 44 attached to the lumbar member 42, wound around the torso of the operator 11, and fixed to the torso. The back muscle motion assisting device further includes: a connection member 38 attached to the lower end of the fixed link 28 for maintaining a prescribed length and passing through beneath the crotch of the operator to reach the front side of the body; and a holding member 40 attached to the top end of the connection member 38 and contacting the groin of the operator 11. The shoulder member 12 is connected to the fixed link 28 so as to be relatively moveable by a first linear actuator 16 and a second linear actuator 32, each using a ball screw.

Description

  The present invention relates to a back muscle movement assisting device that is attached to a worker's back and assists the back muscles.

  In recent years, moving to transport heavy objects in confined spaces, civil engineering work and disaster recovery work in places where it is difficult to enter heavy machinery can be transferred and transported. 2. Description of the Related Art A muscle force assisting device that is worn by an operator and assists in the movement of a body when transporting a heavy transported object in a field such as a nursing care work has been proposed.

  For example, as a device that reduces fatigue of posture maintenance in a crooked posture or middle waist work in farm work or the like, the muscle force assisting device disclosed in Patent Document 1 has one end in the longitudinal direction at the shoulder of the operator An elastic body that is attached to the lower body of the worker and extends along the back of the worker, a bending sensor that detects a bending state of the upper body of the worker, and an elastic body And a control unit for controlling the amount of expansion of the elastic body by the electric wire winder according to the detection result of the bending sensor.

  Further, as disclosed in Patent Document 2 and Patent Document 3, a back frame that is attached to the worker's back and is movable to follow the operator's forward tilt, and a trunk of the worker attached to the back frame. A shoulder belt that extends forward and supports the user's trunk front side, a thigh plate that is worn on the front side of the operator's lower limb, one end connected to the thigh plate, and the other end Lumbar assist provided with a connecting frame that is connected to the back frame at a joint so as to be relatively movable and can maintain an unbent shape during relative movement, and an actuator that stops the user from tilting the back frame forward in the operating state. Devices have also been proposed. This waist assist device drives a pneumatic actuator carried on the back, rotates a pulley on the waist, pushes a pad placed on the knee, and creates a force at the time of standing up. This is to assist the force that rises by pressing the pad installed on the thigh when the pneumatic actuator expands and contracts.

JP 2008-67662 A JP 2011-87926 A WO2011-036906

  In the case of Patent Document 1 of the background art described above, in order to maintain a bent posture or a middle waist posture, power must be continuously supplied to the electric wire winder, which is costly. In addition, force is applied in the direction of contraction to the back, the burden on the body is large, and the force is not used to lift the luggage.

  In addition, in the case of the devices disclosed in Patent Document 2 and Patent Document 3, it assists the force to rise by pressing the thigh plate installed on the thigh, and although it can assist up to lifting heavy objects, Since subsequent walking is impossible, it becomes a fundamental problem as an assist system for carrying heavy objects. In addition, since the thigh is forcibly pressed by the air pressure and forcedly driven from the bent state to the standing state, there is a problem that heavy objects cannot be maintained in the middle waist posture. Moreover, the pneumatic actuator cannot be finely controlled, and is difficult to stop while maintaining the middle waist posture while standing up, and consumes power while it is stopped in the middle waist posture. For example, it is necessary to keep a middle waist posture during a transfer operation from a bed to a wheelchair at a nursing care site, but it is difficult to use at a nursing care site because this cannot be done. In addition, a compressor is required and the apparatus is large. Further, similarly to the device disclosed in Patent Document 1, it is necessary to continue to supply electric power in order to maintain a bent posture or a middle / lower back posture, which is costly.

  In addition, a muscle force assisting device in which a DC motor is provided in a joint such as a shoulder, an elbow, or a knee has been proposed. This is because the motors of each joint are driven for a certain period of time when the load is lifted or when walking, because the motors of each joint are driven in a manner that “gives a specific torque for a specific time” against changes in myoelectricity and center of gravity. It provides a certain amount of exercise assistance. The movement desired by the worker is programmed in advance and various movements are made possible by switching and responding each time. However, the speed and posture maintenance cannot be arbitrarily changed during the movement of the worker. Therefore, it is only a patterned movement, and it cannot follow the movement of the worker and stop in a forward-bending state at an arbitrary angle. Will occur. Moreover, when maintaining a heavy object, it is necessary to keep a huge current flowing through the motor, and the operating time cannot be extended. Since a DC motor is used, when torque is generated, the load on the motor increases as the weight of the transported luggage increases, which not only increases the amount of current but also makes it difficult to control the torque. Further, similarly to the muscular strength assisting device using the pneumatic actuator described above, power is consumed while the vehicle is stopped in a mid-lumbar posture while standing up, and costs are increased.

  Further, there is a muscle strength assisting device that attaches a wire to a belt stretched on the back, winds the wire by a motor installed on the waist, and pulls the back up. This is because the device does not become large because it has a drive mechanism along the body, but the assistable force is weak, it is impossible to maintain heavy objects, etc., and only the effect of reducing fatigue and burden can be obtained. . Further, when the back is pulled with a wire, a compressive force acts strongly on the back and a load is applied to the body, and the force from the motor is not used to effectively lift the load.

  The present invention has been made in view of the problems of the background art described above, and has a simple structure and can reliably assist the movement of the back muscles when lifting heavy objects and can walk while assisting the back muscles. An object of the present invention is to provide a back muscle movement assisting device capable of facilitating the work of transporting heavy objects.

  The present invention includes a shoulder member that is attached between a pair of shoulder blades on a worker's back, a pair of shoulder straps that are attached to the shoulder member and locked to the shoulder of the worker, and a vertical movement along the operator's spine. A fixed link attached in a direction, a waist member attached in the middle of the fixed link, abutting against an operator's waist, a belt attached to the waist member and wound around the operator's torso, and the fixed link A long member that is attached to the lower end and maintains a predetermined length, passes through the operator's crotch and reaches the front side of the body, and a connecting member that is attached to the tip of the connecting member and contacts the groin of the worker There is provided a holding member in contact with each other, and the shoulder member and the fixed link are relatively relative to each other on two axes of a first linear actuator that moves the shoulder member and a second linear actuator that changes an angle of the first linear actuator. Rotatably to be connected, the first linear actuator and the second linear actuator is a spine operation assisting device that uses a ball screw. An intermediate portion of the first linear actuator is attached to an upper end portion of the fixed link so as to be rotatable on a virtual circle parallel to an operator's spine, and one end portion of the first linear actuator is connected to the shoulder member. And the other end is rotatably connected to one end of the second linear actuator. The other end of the second linear actuator is pivotally connected to the lower end of the fixed link. In the back muscle movement assist device, when the operator changes from an upright posture to a forward bending posture, the first linear actuator extends to push the shoulder member forward, and at this time, the second linear actuator also extends, When the end of the first linear actuator opposite to the shoulder member is raised and the operator changes from a forward bent posture to an upright posture, the first linear actuator contracts to cause the shoulder member, The two linear actuators are also contracted to gradually lower the end portion of the first linear actuator opposite to the shoulder member, and the two linear actuators are compactly drawn near the back of the operator.

  In addition, a first rod can be extended and contracted at one end of the first linear actuator, the first rod is attached to the shoulder member, and a second rod can be expanded and contracted at one end of the second linear actuator. The second rod is attached to the first linear actuator.

  In addition, a movable link arranged substantially parallel to the expansion / contraction direction of the first rod is attached to the side of the first linear actuator, and one end of the movable link is rotatable to the upper end of the fixed link. The other end is rotatably attached to the end of the second linear actuator.

  In addition, an operation button may be provided near the shoulder strap. The connecting member is a flexible member such as a string body that does not have elasticity. Further, the holding member is a rod-shaped member formed by winding an elastic body around a side peripheral surface of a hard rod body, and is set so that the longitudinal direction of the hard rod body is positioned horizontally and parallel to the inguinal portion. To do.

  The back muscle motion assisting device of the present invention has a simple structure, reliably assists the motion of the back muscles when lifting heavy objects, and can walk while assisting the lifting operation by the back muscles, thereby carrying heavy objects. Can be easily. It can be stopped and maintained in various postures, and while it is maintained, it does not consume power even at high loads, and the energy cost is low. When lifting heavy objects, it is possible to apply a force to lift the upper body at an angle close to the direction of raising the upper body. it can. The waist angle can be bent as much as necessary when the operator needs it, and free movement is possible.

It is the schematic which shows the state which the worker of the back muscle movement assistance apparatus of one Embodiment of this invention was in a forward bending posture. It is the schematic which shows the state in the middle of the operator of the back muscle movement assistance apparatus of this embodiment changing from a forward bending posture to an upright posture. It is the schematic which shows the state by which the operator of the back muscle movement assistance apparatus of this embodiment became an upright posture. It is a front view of the back muscle movement auxiliary device of this embodiment. In the lifting operation and the lifting operation of the back muscle movement assist device of this embodiment, the order of operation and the synchronization timing of the first linear actuator 16 and the second linear actuator 32 are set in three patterns, and are described in the schematic diagram It is. Fig. 5 shows the graph showing the electromyogram of the spine standing muscles when lifting and lifting heavy objects with and without using the back muscle movement assist device of this embodiment with pattern 1 in Fig. 5 It is. The same experiment as FIG. 6 was conducted with three other subjects and represented in a graph. With respect to patterns 1 to 3 in FIG. 5, when the back muscle movement assisting device of this embodiment is used and when it is not used, the weight lifting and lifting operations are performed, the myoelectricity of the spine standing muscle is measured, and the graph is displayed. It is a representation. The same experiment as FIG. 8 was conducted with the other three subjects and represented in a graph. For the pattern 2 in FIG. 5, when the back muscle movement assisting device of this embodiment is used or not, the weight of two different weights is lifted and lowered, and the myoelectricity of the spine standing muscle is measured. And represented in a graph.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. 1 to 4 show an embodiment of the present invention, and a back muscle movement assisting device 10 of this embodiment is provided with a shoulder member 12 to be attached in the vicinity of a pair of shoulder blades on the back of an operator 11, The shoulder member 12 is made of a material having flexibility and elasticity so as not to damage the muscle, bone and skin of the worker 11. A pair of shoulder straps 14 that are placed on the shoulder of the operator 11 are attached to the shoulder member 12. The pair of shoulder straps 14 passes from the top of the shoulder of the operator 11 to the front of the chest, crosses each other, passes through the armpit on the opposite side, turns around the back, and reaches the shoulder member 12. The shoulder strap 14 is provided with a detachable buckle (not shown), and the buckle is provided with a length adjusting means (not shown). In the vicinity of the shoulder strap 14, an operation button (not shown) to be described later is provided.

  A first linear actuator 16 is connected to the shoulder member 12. The first linear actuator 16 uses a ball screw, and the first linear actuator 16 is provided with a first rod 18, and the first rod 18 has a male screw portion and is not shown with a ball (not shown) interposed therebetween. Screwed onto the nut. The first rod 18 is provided so as to protrude outward from one end 16a of the main body of the first linear actuator 16, and the first rod 18 is rotated around an axis by a motor (not shown) to change the protrusion amount. The distal end portion 18a of the first rod 18 is fixed to the shoulder member 12, and can be rotated in the vertical direction.

  The main body of the first linear actuator 16 is fixed to the movable link 22 via the mounting member 20 at the end 16b opposite to the end 16a. The movable link 22 is substantially parallel to the expansion / contraction direction of the first rod 18 and is disposed below the side peripheral surface 16c of the main body of the first linear actuator 16, and the side peripheral surface 16c of the first linear actuator 16 is also a fixing member. 24 are connected and fixed. A fixed link 28 is connected to the end of the movable link 22 opposite to the attachment member 20 attached to the first linear actuator 16 via a rotation shaft portion 26. The fixed link 28 is fixed to the movable link 22 so as to be able to rotate in the vertical direction. The fixed link 28 is attached along the spine of the worker 11 and extends substantially vertically downward to reach the crotch of the worker 11.

  A waist member 42 that contacts the waist of the operator 11 is provided slightly above the lower end of the fixed link 28. The waist member 42 is provided with a belt 44 that is wound around and fixed to the trunk of the worker 11. A removable buckle (not shown) is provided in the middle of the belt 44, and a length adjusting means is provided on the buckle.

  A second linear actuator 32 is connected to the lower end of the fixed link 28. The second linear actuator 32 uses a ball screw. The second linear actuator 32 is provided with a second rod 34. The second rod 34 has a male screw portion and a nut (not shown) via a ball (not shown). Are screwed together. The second rod 34 is provided so as to protrude laterally from one end 32a of the main body of the second linear actuator 32, and the second rod 34 is rotated around an axis by a motor (not shown) to change the protruding amount. The distal end portion 34a of the second rod 34 is connected to the position of the movable link 22 attached to the first linear actuator 16 at a position close to the attachment member 20 via the rotation shaft portion 36, so that the shaft can be rotated in the vertical direction. It has been stopped. An end portion 32b of the second linear actuator 32 opposite to the end portion 32a is connected to the fixed link 28 via the rotation shaft portion 30, and is fixed so as to be able to rotate in the vertical direction.

  The movable link 22, the fixed link 28, and the second linear actuator 32 form a triangle on the back surface of the worker 11, and the first linear actuator 16 is supported by the triangle. Rotating shaft portions 26, 30, and 36 are provided at the respective corner portions of the triangle, and each angle of the triangle can be changed by the second linear actuator 32, whereby the angle of the first linear actuator 16 can be changed. .

  A connecting member 38 that passes under the crotch of the worker 11 and reaches the front side of the body is provided at the lower end of the fixed link 28, and a holding member that abuts on the groin portion of the worker 11 at the tip of the connecting member 38. 40 is provided. The connecting member 38 may be a member that does not have elasticity, and may be, for example, a string or a rod. The connecting member 38 is provided with a length adjusting means (not shown) and adjusts the length so that the holding member 40 is in close contact with the groin portion of the worker 11 when the back muscle movement assisting device 10 is mounted. The holding member 40 is only required to be able to engage with the inguinal portion by a member that does not easily deform. For example, the holding member 40 is a rod-shaped member that is formed by winding a sponge 43 that is an elastic body around a side peripheral surface of an iron pipe 41 that is a hard rod. Is. The holding member 40 is set so that the longitudinal direction of the iron pipe 41 is positioned horizontally and parallel to the groin portion.

  In this embodiment, the operation buttons of the first linear actuator 16 and the second linear actuator 32 are provided at positions that can be operated on a body part other than the hand, such as around the chin of the shoulder strap 14. A remote controller operated by a third party may be provided.

  Here, the characteristics of the linear actuator will be described. Linear actuators use ball screws and are used in electric beds, power shovels, etc. When maintaining a specific arm angle, power is not consumed even at high loads, and it is easy to maintain a certain position. It is. Even when a high load is applied, the position does not change unless the motor is commanded due to the principle of the ball screw, and all loads can be applied to the actuator even when lifting heavy objects. However, there is a problem that the degree of freedom to bend the joints is reduced instead of having a high angle maintenance capability for high loads. In this respect, humans are more powerful than muscular assist devices using DC motors or pneumatic actuators. Hinders the movement of joints such as knees and elbows. However, this back muscle movement assisting device 10 is intended for assisting only the lower back, and the hip joint has fewer scenes that need to move faster than other knee and elbow joints, especially when carrying heavy objects. Since the load almost comes to the waist, there is no problem because the purpose is to assist the waist.

  Here, the fixing at the groin portion by the holding member 40 will be described. An inguinal part means the part before the base of the left and right thighs. If the holding member 40 is not fixed at the groin, the back muscle movement assisting device 10 operates to lift the load with the belt 44 connected to the waist, and the weight of the load 46 even if the belt 44 is installed on the waist. The back muscle movement assisting device 10 itself is shifted forward or tilted forward, and the lower end of the fixed link 28 is separated from the operator 11, so that a certain degree of assistance is felt, but the weight of the heavy load is securely deposited. Will not be possible. By fixing the holding member 40 at the groin portion, when lifting a heavy object, a force that pulls in the reverse direction by the groin portion is generated with respect to the force that the back muscle movement assisting device 10 is displaced or tilted forward, and the fixed link The lower end portion of 28 is firmly attached without leaving the operator 11, and the weight 46 can be lifted by leaving all the weight of the heavy load in the back muscle movement assisting device 10.

  Next, a biaxial structure using the first linear actuator 16 and the second linear actuator 32 will be described. In the forward bending posture and the upright posture of the worker 11, the distance from the waist to the shoulder varies greatly by bending or stretching the spine. To absorb this variation, the first linear actuator 16 and the second linear actuator 32 are used. The two-axis structure corresponds to the bending of the spine. When trying to lift a heavy object by bending the waist firmly, the waist is bent and the spine bends greatly, so it is difficult to generate the force to lift the back only by rotating the waist. If there is no first linear actuator 16 and only the expansion and contraction of the second linear actuator 32 is used, the second linear actuator 32 exerts a force that shrinks the rounded back and lifts the back rather than lifting the load. The pressure and pressure led to pain, and no sense of assistance was born.

  Next, the usage method of the back muscle movement assistance apparatus 10 of this embodiment is demonstrated. The shoulder member 12 of the back muscle movement assisting device 10 is abutted between a pair of scapulas on the back of the worker 11, the pair of shoulder straps 14 are crossed on the shoulders and crossed on the front side of the body, and locked with a buckle, thereby adjusting the length. Close contact with the body by means. The belt 44 is wound around the body and locked with a buckle, and the waist member 42 is brought into close contact with the waist by the length adjusting means. The holding member 40 is brought into contact with the inguinal portion through the connecting member 38 under the crotch, and the length of the connecting member 38 is adjusted by the length adjusting means so as to be in close contact with the body. Thereby, as shown to FIG. 3, FIG. 4, installation of the back muscle movement assistance apparatus 10 is completed. The fixed link 28 is attached substantially vertically along the back of the worker 11 in the upright posture, and the triangle formed by the movable link 22, the fixed link 28, and the second linear actuator 32 is attached. At this time, the first linear actuator 16 and the second linear actuator 32 are in a contracted state, and the first linear actuator 16 has a position where the tip end portion 18a of the first rod 18 is higher than the end portion 16b of the first linear actuator 16. It is supported by the inclination which leaves | separates from the worker 11 and reaches a low position near the waist as it approaches the end 16b. Since the first linear actuator 16 is tilted and supported, the angle α of the first rod 18 with respect to the back of the worker 11 is increased, and the contracting force of the first rod 18 is efficiently transmitted to the operation of the worker 11.

  Then, a power source is connected to the first linear actuator 16 and the second linear actuator 32. As shown in FIG. 1, when the worker 11 bends forward to lift the load 46 placed on the floor, the first rod 18 of the first linear actuator 16 and the second rod 34 of the second linear actuator 32 are moved. It stretches along with the body's forward bending action and holds the luggage 46 by hand. At this time, the end 16b of the first linear actuator 16 is pushed up by the second linear actuator 32, passes through the horizontal direction, and the end 16b is set at a higher angle than the tip 18a of the first rod 18 than the horizontal. The end 16b comes to a position away from the operator 11.

  Next, when raising the upper body while holding the load 46 by hand and returning to the upright posture, the first rod 18 of the first linear actuator 16 and the second rod 34 of the second linear actuator 32 as shown in FIG. Is gradually reduced according to the movement of the body. When the worker 11 approaches an upright posture, the first linear actuator 16 passes through the horizontal direction and returns to the state shown in FIG. 3, and the second linear actuator 32 is also contracted, so that the first linear actuator 16 is relatively close to the vertical angle. Therefore, the operator 11 is drawn close to the back of the worker 11 and becomes compact. When the first linear actuator 16 and the second linear actuator 32 are contracted when the worker returns from the forward bending posture to the upright posture, the lower end portion in the vicinity of the rotation shaft portion 30 of the back muscle movement assisting device 10 in FIG. Although the upper end portion of the drawing rotates clockwise in the center of the drawing and tries to fall forward, the holding member 40 is supported by the groin portion so that the rotation is suppressed and the upper body can be surely raised, and the weight of the load 46 All of the above can be stored in the back movement assisting device 10 and the load 46 can be lifted. Then, the user walks upright with the load 46 and carries it to the target location, stretches the first linear actuator 16 and the second linear actuator 32, bends forward, and lowers the load 46 to an arbitrary height such as a floor. . Note that the first linear actuator 16 and the second linear actuator 32 can keep the length constant with a ball screw so that the posture can be accurately maintained regardless of whether the worker 11 is in the upright posture or the forward bending posture. An arbitrary posture between an upright posture and a forward bending posture can be kept.

  According to the back muscle movement assisting device 10 of this embodiment, the back muscle can be reliably assisted during lifting of heavy objects, and walking can be performed while assisting the back muscles, thereby making it easy to carry heavy objects. Can be. Because it uses a ball screw, it can be stopped and accurately maintained in various postures, and while it is being maintained, it does not consume power even at high loads, and there is no energy cost consumption, saving energy. is there. When lifting heavy objects, it is possible to apply a force to lift the upper body at an angle α close to the direction in which the upper body is raised, so that there is no load on the waist and spine, energy efficiency is ensured, and back muscle assistance is ensured It can be carried out. It is possible to bend forward as much as necessary when the operator needs it, and free movement is possible. Moreover, it is possible to absorb the fluctuation of the distance from the waist to the shoulder that occurs when the back is bent or stretched, and the burden on the body is reduced.

  Further, since the back muscle motion assisting device 10 is supported from the front of the body by the holding member 40 at the groin portion, the back muscle motion assisting device 10 does not fall down and the force does not escape, and the lifting motion can be assisted with a large force. Since the holding member 40 has a rod shape and is attached substantially horizontally and parallel to the groin, the degree of freedom of the foot is ensured and the user can walk freely with the luggage 46. Since the back motion assisting device 10 is relatively lightweight, the burden on the operator 11 is small and the attachment / detachment is easy. Therefore, the back motion assisting device 10 can be easily used in a nursing facility, a disaster site, a construction site, etc. for efficient transportation work. Can assist. In addition, when an operation button is provided in the vicinity of the shoulder strap 14, the operator 11 can operate with the jaw or the like with the luggage 46 in both hands. The posture of the worker 11 can be changed when necessary, and free movement is possible. It is convenient because a remote controller can be operated remotely by a remote controller.

  Next, an experiment was conducted in which the back muscle movement assisting device 10 of the present invention was worn and the load 46 was lifted, and the myoelectricity generated at that time was measured to examine the effect. Physiologically, when lifting the load 46, it is known that myoelectricity appears in two places, the standing muscle of the spine and the psoas major. Here, the myoelectricity of the standing muscle of the spine is measured and evaluated. did. The experiment was performed by changing the operation timing of the first linear actuator 16 and the second linear actuator 32 of the back muscle movement assist device 10. FIG. 5 is a schematic diagram illustrating the operation timing of the first linear actuator 16 (1 in the figure) and the second linear actuator 32 (2 in the figure) in three patterns during the lifting operation and the lowering operation. Is. Pattern 1 assists the first linear actuator 16 and the second linear actuator 32 to operate synchronously after 5 seconds as a preparation for lifting, and continuously lift for 8 seconds. It assists the operation and the lowering operation continuously for 8 seconds. In pattern 2, at the start of the lifting operation and the lowering operation, the first linear actuator 16 operates with a delay of 1 second from the second linear actuator 32 and continues for 8 seconds each, and assists for a total of 9 seconds. In pattern 3, at the start of the lifting operation and the lowering operation, the first linear actuator 16 operates 3 seconds behind the second linear actuator 32 and continues for 8 seconds each, and assists for a total of 11 seconds. Although it has not yet been agile, it does not seem necessary to be so fast when moving heavy objects. Furthermore, since the speed can be controlled by selecting the actuator and selecting the voltage, it is possible to determine what performance is required at which site and cope with it.

  FIG. 6 shows the measurement of the myoelectricity of the erector spine by performing the lifting and lowering operations of the 10 kg load 46 in the pattern 1 of FIG. 5 with and without the assist by the back muscle movement assist device 10. It is represented in a graph. The vertical axis represents a value obtained by plotting a time average value for 200 ms of a waveform obtained by subjecting myoelectricity to full-wave rectification. According to this, it can be seen that the myoelectricity is reduced when the back muscle operation assisting device 10 is used, and the back muscle assisting effect of the back muscle operation assisting device 10 is higher than when it is not.

  FIG. 7 is a graph showing the same experiment as FIG. 6 performed by the other three test subjects. The waveforms of FIG. 6 are shown with and without assistance by the back muscle movement assisting device 10. Indicates the value obtained by time integration in the “lifting” and “lowering” sections. In any subject, it can be seen that the myoelectricity is reduced when the back muscle movement assisting device 10 is used, compared with the case where it is not used, there is almost no individual difference, and the back muscle assisting effect of the back muscle motion assisting device 10 is high. .

  FIG. 8 measures the myoelectricity of the erector spine by performing the lifting and lowering operations of the 10 kg load 46 with and without using the back muscle movement assisting device 10 for patterns 1 to 3 in FIG. And represented in a graph. According to this, it is understood that myoelectricity is large when there is no assist. When the back muscle movement assisting device 10 is used in pattern 1, it can be seen that the myoelectricity is smaller than in the case without assist, but the myoelectricity is slightly higher during the lifting operation than in other operations, and the assist is It turns out that it is not enough. It can be seen that when the back muscle movement assisting device 10 is used in the pattern 2 (shift of the actuator 1 second) and the pattern 3 (shift of the actuator 3 seconds), the myoelectricity is dramatically lowered. First, the second linear actuator 32 operates and the waist begins to bend. After 1 second or 3 seconds, the first linear actuator 16 operates and the back bends, so that the operator 11 is naturally holding the back. It can be seen that all the weight of the load 46 is stored in the back movement assisting device 10 and is fully assisted.

  FIG. 9 is a graph showing values obtained by performing time integration in the “lifting” and “lowering” sections in the same manner as in FIG. In any subject, myoelectricity decreases with assist than without assist, but it can be seen that the effect of patterns 1 to 3 with assist is different depending on the subject. It seems that there is an influence such as the difference in the height of the subject, and it is necessary to search in the future.

  FIG. 10 is a graph showing a case where the back muscle movement assisting device 10 is used and a case where the back muscle movement assisting device 10 is used and a case where the load 46 having a different weight of 10 kg and 20 kg is lifted and lowered, respectively. It is shown in The operations of the actuators of the back movement assisting device 10 are performed by shifting one second as in pattern 2. According to this, if the weight of the load increases, the myoelectric amount naturally increases without assistance, but with the assistance using the back muscle movement assisting device 10, the load is hardly applied to the back, and the assist is sufficiently assisted. It can be seen that the back muscle assist effect of 10 is high.

DESCRIPTION OF SYMBOLS 10 Back muscle movement auxiliary | assistance apparatus 11 Worker 12 Shoulder member 14 Shoulder strap 16 1st linear actuator 18 1st rod 20 Attachment member 22 Movable link 24 Fixed member 26,30,36 Rotating shaft part 28 Fixed link 32 2nd linear actuator 34 Second rod 38 Connecting member 40 Holding member 41 Iron pipe 42 Lumbar member 43 Sponge 44 Belt 46 Luggage

Claims (6)

  A shoulder member attached between the pair of shoulder blades on the operator's back, a pair of shoulder straps attached to the shoulder member and locked to the operator's shoulder, and attached in the vertical direction along the operator's spine A fixed link, a waist member attached in the middle of the fixed link, abutting against the operator's waist, a belt attached to the waist member and wound around the operator's trunk, and attached to the lower end of the fixed link A connecting member that is a long object that maintains a predetermined length and passes under the operator's crotch and reaches the front side of the body, and a holding member that is attached to the distal end of the connecting member and contacts the groin of the operator The shoulder member and the fixed link are relatively movable on two axes of a first linear actuator that moves the shoulder member and a second linear actuator that changes an angle of the first linear actuator. The first linear actuator and the second linear actuator use ball screws, and an intermediate portion of the first linear actuator is parallel to the operator's spine at the upper end of the fixed link. It is rotatably mounted on a virtual circle, one end of the first linear actuator is connected to the shoulder member, and the other end is rotatably connected to one end of the second linear actuator, The other end portion of the second linear actuator is rotatably connected to the lower end portion of the fixed link.   A first rod is extendably provided at one end of the first linear actuator, the first rod is attached to the shoulder member, and a second rod is provided to be extendable at one end of the second linear actuator. The back muscle movement assisting device according to claim 1, wherein the second rod is attached to the first linear actuator.   A movable link arranged substantially parallel to the direction of expansion and contraction of the first rod is attached to the side of the first linear actuator, and one end of the movable link is rotatably attached to the upper end of the fixed link. The back muscle movement assisting device according to claim 1, wherein the other end portion is rotatably attached to an end portion of the second linear actuator.   The back muscle movement assisting device according to claim 1, wherein an operation button is provided in the vicinity of the shoulder strap.   The back muscle movement assisting device according to claim 1, wherein the connecting member is a flexible member having no stretchability. The holding member is a rod-shaped member formed by winding an elastic body around a side peripheral surface of a hard rod body, and is set so that the longitudinal direction of the hard rod body is positioned horizontally and parallel to the groin portion. Item 10. A back muscle movement assist device.