Work assistance device

Abstract

This work assistance device comprises: an attachment portion 10 that can be attached to a trunk Pm; a connection tool 20 that can be attached to and detached from a connection portion 101 provided on a heavy object W and can be gripped by a worker P with a hand Ph; a belt 40 to one end 40a of which the connection tool 20 is connected; and a winding device R that is connected to the attachment portion 10 and can wind up the other end side of the belt 40. The winding device R includes a lock mechanism 30 that can lock the pull-out position of the belt 40 so as to restrict further drawing when the one end 40a of the belt 40 is pulled out by a certain pull-out length.

Description

Work Support Device

[0001] The present invention relates to a work support device, and more particularly to a work support device that assists a worker in lifting or holding a heavy object.

[0002] The above-mentioned work support devices are well known in the art, as shown in, for example, Patent Documents 1 to 3. In these patent documents, one end of an auxiliary cable (e.g., a harness, a string-like member, a wire, etc.) is attached to the arm or hand of a worker, and an assisting force for work assistance can be applied from the auxiliary cable to the arm or hand of the worker.

[0003] JP-T-2015-524752 A JP-A-2018-149624 JP-A-2016-129916

[0004] In the work support device of Patent Document 1, the base of the harness serving as an auxiliary cable is supported by a sturdy metal frame fixed to the back, and the harness is not structured to be wound up and stored, so the entire harness is always exposed even when not working. As a result, there is a possibility that the harness may interfere with normal movements when not working, and the use of a sturdy metal frame increases the weight of the device, which increases the burden on the worker.

[0005] In the work support device of Patent Document 2, the bases of the string-like members 161, 162 serving as auxiliary cables are supported by sturdy metal frames (i.e., the back member 110 and the support member 140) attached to the back. Rotating the metal frames with an actuator 151 assists the worker in raising their upper body, thereby lifting a heavy load by pulling up the worker's hands via the string-like members. In this case, the string-like members are not structured to be wound up and stored, and the string-like members and the metal frame extending above the shoulders are always exposed, even when not working. Therefore, there is a possibility that normal movements when not working may be hindered by the string-like members and the rigid frame. Furthermore, rotating the sturdy rigid frame with an actuator for lifting luggage increases the weight of the device, which increases the burden on the worker.

[0006] Furthermore, the work support device of Patent Document 3 has a structure in which the base of a wire 31 serving as an auxiliary cable is wound up by a hoisting motor 13 fixed to the back via the upper end of a sturdy rigid arm unit 11 that is fixed to the back and extends high above the head, and the worker is assisted in lifting a heavy load by attaching one end of the wire 31 hanging down from the upper end of the rigid arm unit 11. Therefore, normal movements when not working are hindered by the wire 31 that hangs down longer than the upper end of the rigid arm unit 11, and for example, the worker must work carefully to avoid getting surrounding objects tangled in the wire, and also there are problems in that the worker must work while supporting heavy loads such as the large rigid arm unit 11, the load-lifting motor 13, and the battery 40, which increases the burden on the worker.

[0007] The present invention has been made in view of the above circumstances, and has as its object to provide a work support device that can solve the above problems of conventional devices with a simple structure.

[0008] In order to achieve the above-mentioned object, the present invention is a work support device that assists a worker in lifting and holding a heavy object, and is characterized in that it comprises an attachment part that can be attached to the worker's torso, a connecting device that can be attached and detached to a connected part provided on the heavy object and can be held by the worker's hand, a belt to which the connecting device is connected at one end, and a winding device that is connected to the attachment part and can wind up the other end of the belt, and the winding device is characterized in that it comprises a biasing mechanism that applies a biasing force to the belt in the winding direction, and a locking mechanism that can lock the pull-out position of the belt when the one end of the belt has been pulled out to an arbitrary pull-out length to restrict further pull-out.

[0009] In addition to the first feature, the present invention has a second feature in that the connecting device is a fastening device that can be fastened to and released from a fastened portion serving as the connected portion provided on the heavy object.

[0010] In addition to the second feature, the present invention has a third feature in that the engaged portion is an engagement hole provided in the heavy object, the engagement device is a hook having a hook portion at its tip that can be hooked into the engagement hole, and the one end of the belt is connected to the base of the hook.

[0011] In addition to the first or second feature, the present invention has a fourth feature in that the retracting device is attached to the worker's waist via the attachment portion so that the middle portion of the belt pulled out from the retracting device is slidably hung on the worker's shoulders.

[0012] In addition to the first feature, the present invention has a fifth feature in that the locking mechanism is connected to an unlocking command device for unlocking the locking mechanism before the start of the work and after the end of the work.

[0013] In addition to the fifth feature, the present invention has a sixth feature in that the release command device includes at least one of an automatic release command device that automatically unlocks the locking mechanism before the start and after the end of the work based on the detection results of a detection device that can detect changes in the contact surface pressure or relative distance between the connector and the heavy object before and after the start and end of the work, or a manual release command device that unlocks the locking mechanism at any time based on an operation input to a release operation device that can be manually operated at will.

[0014] In addition to the first or second feature, the present invention has a seventh feature in that the connector can be held by an operator's hand and its posture controlled while connected to the connected portion.

[0015] Furthermore, in addition to the first or second feature, the present invention has an eighth feature in that the attachment portion includes a waist belt that goes around the worker's waist and is held on the waist, and the retracting device is connected to the waist belt.

[0016] In addition to the eighth feature, the present invention has a ninth feature in that a leg belt is connected to the waist belt so that it can be worn around at least one of the worker's thighs.

[0017] In addition to the first or second feature, the present invention has a tenth feature in that the belt has a bifurcated portion that branches into two midway from the other end side toward the one end side.

[0018] Furthermore, in addition to the first or second feature, the present invention has an eleventh feature in that it further comprises a work jacket that can be worn by the worker so as to cover at least the upper part of the worker's shoulders, and the jacket is provided with a belt guide through which the belt can slide so as to maintain the middle portion of the belt resting on the worker's shoulders.

[0019] According to a first aspect of the present invention, there is provided a device for lifting or holding a heavy object, the device comprising: an attachment portion attachable to a torso of a worker; a coupler detachable from a connected portion of a heavy object and capable of being held by the hand of the worker; a belt connected to one end of the coupler; and a reeling device connected to the attachment portion and capable of reeling in the other end of the belt, the reeling device including a biasing mechanism that applies a biasing force to the belt in a reeling direction and a locking mechanism that locks the reeled-out position of the belt so as to restrict further reeling when one end of the belt has been reeled out to a desired length. As a result, when one end of the belt is reeled out to an appropriate length from the reeling device fixed to the torso of the worker and the coupler is connected to the connected portion of the heavy object, and in this state, further reeling of the belt is restricted by the locking mechanism, at least a portion of the load on the worker's arms or hands can be transferred to the torso through the belt and the reeling device, thereby reducing the burden on the worker and providing a work support effect.

[0003] Furthermore, since the connecting device and the connected part remain connected during the support work, there is no risk of the heavy object coming off the belt, and the worker does not need to continue to tightly grip the heavy object with his or her hand to prevent it from coming off. This effectively reduces hand fatigue even during long work periods and eliminates the risk of the heavy object falling due to a weakened grip. Furthermore, the retractor has a lightweight and simple structure that simply regulates the belt's withdrawn length with a locking mechanism, and is capable of achieving the above-mentioned work support effect. This eliminates the need for a large rigid frame or load-lifting actuator connected to the retractor, contributing to cost savings and a lighter burden on the worker. Furthermore, since the retractor is used exclusively to regulate the belt's withdrawal during work and can retract the belt at any time during work, as well as before and after work, there is no risk of the belt interfering with normal operations when not working or of other objects being inadvertently entangled in the belt. Furthermore, the belt length can be easily adjusted before and during work. Furthermore, since the connector is connected to one end of the belt, it can be placed in a standby state together with the belt when not in use, so it does not get in the way and is easy to store and manage.

[0020] According to the second feature, the connecting device is a fastener that can be fastened to and detached from a fastened portion provided on a heavy object, so that one end of the belt can be easily fastened and connected to the heavy object by simply hooking the fastener onto the fastened portion on the heavy object. Therefore, handling of the connecting device during support work can be performed more quickly and easily, contributing to improved work efficiency.

[0021] According to a third feature, in the second feature, the to-be-locked portion is a locking hole provided in the heavy object, and the locking device is a hook having a hook portion at its tip that can be hooked into the locking hole, and one end of the belt is connected to the base of the hook. As a result, if the heavy object is, for example, a heavy object stored in a container with a locking hole such as cardboard, or if the heavy object itself originally has a locking hole, the locking hole originally present on the heavy object can also be used as the to-be-locked portion, thereby further simplifying the locking structure between the belt and the heavy object, contributing to cost reduction and further improving workability.

[0022] According to a fourth feature, the reeling device is attached to the worker's waist via the attachment part so that the intermediate portion of the belt pulled out from the reeling device is slidably hung around the worker's shoulders, so that while the reeling device is supported by the worker's waist when assisting with work, the intermediate portion of the belt pulled out from the reeling device passes over the worker's shoulders and supports a heavy object via the connecting device or fastening device at one end of the belt. This not only prevents the reeling device from interfering with work by being located near the waist, but also allows the weight of the heavy object acting on the belt when assisting with work to be received in a balanced manner, not only by the worker's hands and arms holding the connecting device or fastening device, but also by the worker's waist, shoulders, and the surrounding areas, thereby further contributing to reducing the burden on the worker.

[0023] According to the fifth feature, the locking mechanism is connected to an unlock command device for unlocking the locking mechanism before and after work, so that the length of the belt pulled out from the retractor can be easily adjusted to any length by unlocking the locking mechanism with the unlock command device before and after work. As a result, before and after work, the work of attaching and detaching the connector at one end of the belt to the connected part on the heavy object, and the work of holding the heavy object with the connector connected to the connected part can be easily and accurately performed without being hindered by the retractor.

[0024] According to the sixth feature, when the release command device includes an automatic release command device, the automatic release command device can automatically unlock the locking mechanism before the start and end of work, and lock the locking mechanism from the start to the end of work, based on the detection results of a detection device that can detect changes in the contact pressure or relative distance between the connector and the heavy object before and after the start and end of work. When the release command device includes a manual release command device, the locking mechanism can be unlocked at any time based on an operation input to a release operation device that can be manually operated at will, so that the locking mechanism can be unlocked before the start and end of work, and locked from the start to the end of work, depending on whether or not there is an operation input to the release operation device.

[0025] According to the seventh feature, since the connector can be held by the worker's hand and controlled in position while connected to the connected part of the heavy load, the worker can easily pull out the belt by holding the connector by hand at the start of the support work. After pulling out the connector, the worker can support the heavy load while holding the connector by hand in the desired position while connecting the connector to the connected part of the heavy load.

[0026] According to an eighth feature, the attachment part includes a waist belt that goes around the waist of the worker and is held on the waist, and the reeling device is connected to the waist belt, so that the reaction force applied to the reeling device when assisting in lifting or holding a heavy object can be dispersed over a wide area from the waist belt to the waist and its surroundings, reducing the load on the waist. Moreover, the waist belt applies a moderate compressive force to the abdomen, increasing intra-abdominal pressure and contributing to reducing the load on the lumbar vertebrae.

[0027] According to the ninth feature, a leg belt is connected to the waist belt, which can be worn around at least one of the worker's thighs, thereby preventing the winding device itself from slipping up when lifting a heavy object, and allowing the device to be used effectively in an appropriate position.

[0028] According to the tenth feature, the belt has a branched portion where it splits into two on the way from the other end to one end, so that the number of belts used at the other end of the belt can be reduced, and in turn the number of winding devices that need to be installed can be reduced, thereby contributing to cost savings.

[0029] According to the eleventh feature, the apparatus further includes a work jacket that can be worn by the worker so as to cover at least the upper part of the worker's shoulders, and the jacket is provided with a belt guide through which the belt can slide so as to maintain the middle part of the belt resting on the worker's shoulders. This belt guide allows the belt to be smoothly pulled out while accurately maintaining the middle part of the belt resting on the worker's shoulders, thereby improving work efficiency.

[0030] a front view showing a state in which a worker lifts a heavy object while using the work support device according to the first embodiment; a side view showing the state (view taken along an arrow 2X in FIG. 1); a rear view showing the state (view taken along an arrow 3X in FIG. 2); a plan view of the reeling device (a cross-sectional view of 4X-4X in FIG. 3 and a cross-sectional view of 4X in FIG. 5); a partially cutaway perspective view of the reeling device (a partially cutaway perspective view taken along an arrow 5X in FIGS. 3 and 4); a cross-sectional view showing the main parts of the locking mechanism and release command device in the reeling device (a cross-sectional view of 6X-6X in FIG. 4); and a view showing a connection structure between a hook to which a surface pressure sensor is joined and one end of a belt. 1A shows a perspective view of the main part, (b) shows a side view, and (c) shows a side view schematically illustrating a state in which the hook is hooked into a locking hole on the heavy object to support the heavy object, with the hands omitted. The figure shows a connection structure between a hook to which a proximity sensor is attached and one end of a belt, where (a) shows a perspective view of the main part, (b) shows a side view, and (c) shows a side view schematically illustrating a state in which the hook is hooked into a locking hole on the heavy object to support the heavy object, with the hands omitted. The figure shows a standby state before the start of the work to be supported (the hook is not held by the hand). 2 ) standing by with the belt) side view from the same side as FIG. 9 ) showing the preparation state for the work to be supported (the worker holds the waiting hook with his hand and pulls out the belt but has not yet hooked it onto the heavy object) side view corresponding to FIG. 9 ) showing the state immediately after the start of the work to be supported (the worker holds the hook that has been hooked onto the heavy object with his hand and supports the heavy object via the hook and belt) side view corresponding to FIG. 9 ) showing the state immediately after the worker has adjusted the belt length by lifting the heavy object via the hook he is holding during the work to be supported 9 (a) shows the state immediately after the work to be supported is completed (immediately after the hook is released from the heavy object and released from the heavy object); FIG. 14 (b) shows the main part of the locking mechanism and manual release command device in the reeling device according to the second embodiment (a), (b) shows the first example of the manual release command device, and FIG. 14 (c) shows the connecting structure between the hook and one end of the belt in the second example of the manual release command device shown in FIG. 14 (b), (a) is a perspective view of the main part (i.e., a view corresponding to FIG. 7 (a)),and (b) is a side view (i.e., a view corresponding to FIG. 7(b)). Front views corresponding to FIG. 1 and back views corresponding to FIG. 3, showing a state in use of a work support device according to a third embodiment. Front views corresponding to FIG. 1 and back views corresponding to FIG. 3, showing a state in use of a work support device according to a fourth embodiment. These figures show variations of leg belts, with (A) showing a leg belt (first and second embodiments) that wraps diagonally around the thigh, and (B) showing a leg belt that wraps approximately horizontally around the thigh. Diagonal rear perspective view showing a first modified example of the first and second embodiments in which a reeling device is placed on the side of the worker's waist. Diagonal rear perspective view showing a second modified example of the first and second embodiments in which a reeling device is placed in front of the worker's waist. Schematic diagrams showing main parts of a connecting structure that detachably connects one end of the belt to a heavy object, with (A) showing the first modified example, (B) showing the second modified example, (C) showing the third modified example, and (D) showing the fourth modified example.

[0031] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings.

[0032] First, a first embodiment of a work support device according to the present invention will be described with reference to FIGS.

[0033] The work support device A is intended to assist and support a worker P in lifting or holding a heavy object W with his or her hands Ph, and is equipped with an attachment part 10 that can be attached to the torso Pm (in this embodiment, the waist Pw) of the worker P, a connecting device 20 that can be attached and detached to a connected part provided on the heavy object W and can be held by the worker P's hand, a belt 40 to which one end 40a of the connecting device 20 is connected, and a winding device R that is connected to the attachment part 10 and can wind up the other end of the belt 40.

[0034] In this embodiment, the heavy load W includes a heavy load body (not shown) and a container, such as a cardboard box 100, for storing the heavy load body inside. A worker P grasps the cardboard box 100 containing the heavy load body with his or her hands to lift or hold it. In this case, a conventional cardboard box 100 has a pair of opposing side walls each provided with a horizontally elongated locking hole 101 through which the worker's fingers can be hooked. The worker P hooks his or her fingers into the locking hole 101 and grasps the cardboard box 100 as if embracing it, thereby lifting or holding the heavy load W (i.e., the assembly of the heavy load body and the cardboard box 100). The locking hole 101 is an example of a lockable portion (and therefore a connected portion).

[0035] In this embodiment, the connecting device is a hook 20 that can be engaged with and disengaged from the engaging hole 101 of the cardboard box 100. As is clear from Figures 7 and 8, this hook 20 is integrally provided with a base 20b to which the one end 40a of the belt 40 is connected, and a tip 20a that extends downward approximately vertically from the base 20b.

[0036] The base 20b of the hook 20 has a bearing sleeve portion 20bc that is formed in a substantially cylindrical shape and extends substantially horizontally, a horizontal plate portion 20bh that is integrally connected to the bearing sleeve portion 20bc and extends substantially horizontally to the side, and a vertical plate portion 20bv that is also integrally connected to the bearing sleeve portion 20bc and extends substantially vertically downward and continues to the tip portion 20a. Note that the bearing sleeve portion 20bc may be a separate part from the base 20b of the hook 20 and fixed to the base 20b later.

[0037] The tip portion 20a also has an integral hook portion 20at that can be hooked onto the locking hole 101 from below and outside, and the hook portion 20at is formed so that its tip is inverted from the bottom of the tip portion 20a and points diagonally upward toward the cardboard box 100.

[0038] A surface pressure sensor 51A (see FIG. 7) for detecting contact surface pressure, which is a first example of the detection device 51 of the automatic release command device 50 described later, is joined to the inner surface of the hook portion 20at of the tip portion 20a, and a proximity sensor 51B (see FIG. 8) for detecting relative distance, which is a second example of the detection device 51 of the automatic release command device 50, is used on the inner surface of the middle portion near the base portion 20b of the hook 20. The connection cords 28 connected to the sensors 51A and 51B are arranged along the belt 40 and connected to a control device 55 described later.

[0039] In the first embodiment, either the surface pressure sensor 51A or the proximity sensor 51B is provided on the hook 20, but both the sensors 51A and 51B may be provided on the hook 20.

[0040] 7 and 8, in this embodiment, a triangular connecting fitting 25 is used as the means for connecting the base 20b of the hook 20 to the belt 40. The upper vertex 25a of the connecting fitting 25 is fitted into and connected to a mounting fixture 26 that is rotatably supported on the tip of one end 40a of the belt 40, and the mounting fixture 26 can be used to attach and detach the connecting fitting 25 as needed using a conventionally known opening and closing mechanism.

[0041] The aforementioned bearing sleeve 20bc of the base 20b of the hook 20 is rotatably fitted and connected to the linear lower long side 25b of the connecting fitting 25. Thus, the hook 20 is suspended such that its base 20b can rotate about the axis of the lower long side 25b relative to the connecting fitting 25.

[0042] Thus, the hook 20 as a connecting device (locking device) can be held by the hand Ph of the worker P and controlled to the desired position when it is locked (i.e., connected) to the locking hole 101 as the connected part.

[0043] At the start of the support work described below, the worker P can grasp the hook 20 with his / her hand Ph and pull out one end 40a of the belt 40, which makes it easy to pull out the belt 40. After pulling out the belt 40, if the hook portion 20at of the hook 20 is hooked into the locking hole 101 of the cardboard box 100 (i.e., the connected portion on the heavy object W side), the one end 40a of the belt 40 can be quickly and easily connected to the cardboard box 100 via the hook 20, which improves workability.

[0044] Furthermore, when the hook 20 is locked, i.e., connected, to the locking hole 101 of the cardboard box 100 in this manner, the weight of the cardboard box 100 is primarily supported by the waist Pw and shoulders Ps via the belt 40 that extends from the reeling device R fixed to the waist Pw and suspends the hook 20 over the shoulders Ps. This allows the worker P to accurately hold the hook 20 with the hands Ph in a desired posture and accurately support the cardboard box 100 with relatively little effort, and since the worker P does not need to continue to tightly grip the hook 20 or the cardboard box 100 with the hands Ph to support it, fatigue in the hands Ph and arms Pa is effectively reduced.

[0045] The reeling device R is detachably attached to the waist Pw of the worker P via an attachment part 10, and in the first embodiment in particular, a pair of left and right reeling devices R are attached and fixed at a distance from each other to the rear surface of a waist belt 71 that is wrapped around the waist Pw of the worker P. In this case, the attachment part 10 includes the waist belt 71 that is wrapped around the waist Pw of the worker P so as to go around it once and is held at the waist Pw, and a device main body Rm of the reeling device R (a connecting member 13, which will be described later in this embodiment) is connected to the waist belt 71.

[0046] In addition, since the method of wrapping a waist belt around the waist and securing it is generally well known, illustrations and descriptions of the structure of the embodiment in which the waist belt 71 is wrapped around the waist Pw in a detachable manner and secured thereto will be omitted.

[0047] Furthermore, a leg belt 75 that can be attached to at least one (in this embodiment, both) thighs P1 of the worker P is connected to the waist belt 71 via a connection belt 76 and a connector 77. The connection structure may be detachable or non-detachable.

[0048] The work support device A of the embodiment further includes a vest 80 as work outerwear that can be worn by the worker P so as to cover at least the upper part of the shoulders Ps of the worker P. A front belt guide 81f and a rear belt guide 81r are provided on the front and back of the vest 80, respectively, through which the belt 40 slidably passes so as to maintain the intermediate portion of the belt 40 hanging over the shoulders Ps of the worker P. Furthermore, it is desirable that the portions of the vest 80 that cover the left and right shoulders Ps (i.e., the portions on which the belt 40 directly slides when unwinding or retracting) be covered with a durable material that allows the belt 40 to slide easily, as necessary.

[0049] Next, the winding device R will be described in detail mainly with reference to Figures 4 to 6. The device body Rm of each winding device R is formed in a generally U-shape in a plan view, and includes first and second cases 11 and 12 arranged side by side at a distance slightly wider than the width of the belt 40, and a plate-like connecting member 13 that integrally connects one end of the first and second cases 11 and 12. The first and second cases 11 and 12 are each formed as a hollow body, with parallel inner walls 11i and 12i formed as flat plates, and flat-plate-like covers 11c and 12c that are detachably connected to the inner walls 11i and 12i via connecting means (not shown).

[0050] The upper and lower ends of the connecting member 13 extend outward in the vertical direction beyond the first and second cases 11 and 12, and the extending portions 13a and 13b are provided with connection holes 13h for connecting to the waist belt 71. A connecting shaft 18 (e.g., a connecting rivet or a connecting bolt) is inserted into the connection hole 13h, and the connecting shaft 18 connects the waist belt 71 to the extending portions 13a and 13b. Instead of such a connecting structure, the lower extending portion 13b may be detachably connected to the waist belt 71 using a detachable fastener (e.g., a structure similar to that of a seat belt fastener for an automobile). The connecting member 13 and the waist belt 71 thus constitute the attachment portion 10.

[0051] In the embodiment, the upper extension portion 13 is bent sideways, and the bent portion is provided with a slit-shaped belt guide hole 13ah through which the belt 40 pulled out from the reel device R can slidably pass.

[0052] The other end 40b of the belt 40 is coupled to and both ends of the drum shaft 14 around which the belt 40 can be wound rotatably pass through and are supported by the opposing inner walls 11i and 12i of the first and second cases 11 and 12. A biasing mechanism 31 that applies a biasing force to the belt 40 in the winding direction is disposed within the first case 11, and the belt 40 can be pulled out to any desired length by pulling one end 40a against the biasing force with the middle portion of the belt 40 slidably hung on the shoulder Ps of the worker P.

[0053] The urging mechanism 31 mainly comprises a spiral spring 32 whose center is connected to one end of the drum shaft 14, and the other end of the spiral spring 32 is connected to the inner wall of the outer periphery of the first case 11. The resilience of the spiral spring 32 exerts a rotational urging force on the belt 40 in the winding direction (clockwise in FIG. 5, counterclockwise in FIG. 6).

[0054] The retractor R also includes a locking mechanism 30 in the second case 12 that can lock the pull-out position of the belt 40 when one end 40a of the belt 40 has been pulled out to a desired pull-out length, thereby preventing further pull-out. As will be described later, the locking mechanism 30 is connected to an unlocking command device C that unlocks the locking mechanism 30 before and after the start and end of the work to be assisted (for example, lifting or holding a heavy load W). Next, the locking mechanism 30 and the unlocking command device C will be described in order. In the following description, the term "work" simply refers to the work to be assisted, unless otherwise specified.

[0055] The locking mechanism 30 has the same structure as a conventionally known ratchet mechanism and includes a ratchet gear 35 having a large number of ratchet teeth 35t equally spaced on its outer periphery and concentrically connected to the other end of the drum shaft 14, a locking member 36 having a locking claw portion 36t at its tip that can be engaged with and disengaged from the ratchet teeth 35t, a ratchet spring 37 that resiliently urges the locking member 36 in the direction of engagement with the ratchet teeth 35t (upward in Figure 6), and a bearing member 38 fixed to the inner wall 12i of the second case 12 to slidably fit and support the shaft portion 36a of the locking member 36 in the direction of engagement with and disengagement from the ratchet teeth 35t (up and down in Figure 6).

[0056] Thus, the locking member 36 is normally held in an engagement position with the ratchet teeth 35t by the elastic force of the ratchet spring 37. In this state, rotation of the drum shaft 14 in the belt winding direction (counterclockwise in FIG. 6) is permitted, but rotation in the belt withdrawing direction (clockwise in FIG. 6) is restricted, and further withdrawal of the belt 40 is restricted (i.e., the locking mechanism 30 is locked).

[0057] On the other hand, when the release command device C pulls the locking member 36 in the unlocking direction (downward in FIG. 6) away from the ratchet teeth 35t, the locking claw 36t is unlocked from the ratchet teeth 35t (i.e., the locking mechanism 30 is unlocked), and with this release, the ratchet gear 35, and therefore the drum shaft 14, becomes free to rotate in the unwinding direction. This allows the belt 40 to be unwound to any desired unwinding position against the winding biasing force of the biasing mechanism 31.

[0058] Furthermore, even when the locking member 36 is held in the locking position, when one end 40a of the belt 40 is operated in the winding direction and the drum shaft 14 rotates counterclockwise in Figure 6, the ratchet teeth 35t are formed into a tooth shape that allows smooth winding by causing the locking claw portion 36t to slide on the ratchet teeth 35t.

[0059] The release command device C is intended to unlock the locking mechanism 30 before the start and after the completion of the work to be supported, and in the first embodiment, it is configured as an automatic release command device 50 that automatically unlocks the locking mechanism 30 before the start and after the completion of the work based on the detection results of a detection device 51 that can detect changes in the contact pressure or relative distance between the hook 20 (i.e., the locking device / connecting device) and the cardboard box 100 (i.e., the heavy object W) before and after the start and end of the work.

[0060] When the detection device 51 detects a change in the contact surface pressure, a surface pressure sensor 51A joined to the inner surface of the hook portion 20at of the tip 20a of the hook 20 is used, and when the detection device 51 detects a change in the relative distance, a conventionally known non-contact proximity sensor 51B joined to the inner surface of the middle portion closer to the base 20b of the hook 20 is used. The surface pressure sensor 51A can output a detection signal to the control device 55 described below when the hook 20 is engaged with the engaging hole 101 and the weight of the heavy load W acts on the surface pressure sensor 51A (i.e., when the surface pressure sensor 51A detects an increase in the contact surface pressure against the heavy load W when the worker P tries to pick up the heavy load W using the hook 20 held by the hand Ph).

[0061] Furthermore, the proximity sensor 51B can detect changes in the relative distance in cooperation with the detectable body 29, which is made of a magnetic material or magnet and fixed to the heavy object W side (for example, the wall surface of the cardboard box 100 near the locking hole 101). That is, when the worker P tries to hook the hook 20 held in his hand Ph onto the heavy object W, the proximity sensor 51B moves toward the heavy object W together with the hook 20, and when it approaches the detectable body 29 within a predetermined distance, it can output a detection signal to the control device 55 by sensing, for example, a change in the surrounding electrostatic capacitance or magnetic flux.

[0062] As is clear from FIG. 6 , the automatic release command device 50 comprises the above-mentioned detection device 51; an operating cable 52 made of a Bowden cable with one end of an inner wire connected to the shaft 36 a of the locking member 36; an electric actuator 53 which is interlockingly connected to the other end of the inner wire of the operating cable 52 and which can pull and drive the locking member 36 in the lock release direction (i.e., the unlocking direction of the lock mechanism 30) when current is applied; a normally open open / close switch 54 which opens and closes the current circuit of the actuator 53; and a control device 55 which controls the opening and closing of the open / close switch 54 based on the detection result of the detection device 51.

[0063] The actuator 53, the open / close switch 54 and the control device 55 may be integrated into a unit and attached to the winding device R, or may be attached to the clothing of the worker P or the like.

[0064] Although not shown, the control device 55 has a power switch that can be turned on at any time (for example, when the work support device A is in use) and is connected to a power source (for example, a battery), and the control device 55 is activated by turning on the power switch. Thus, before and after the start and end of the work to be supported in this activated state, the control device 55 turns on the open / close switch 54 (and therefore energizes the actuator 53) based on the detection result of the detection device 51 at that time, thereby unlocking the lock mechanism 30. Meanwhile, between the start and end of the work, the control device 55 locks the lock mechanism 30 by turning off the open / close switch 54 (and therefore de-energizes the actuator 53) based on the detection result of the detection device 51 at that time.

[0065] Next, the operation of the first embodiment will be described mainly with reference to FIGS.

[0066] 9 shows the work support device A in a pre-operation state immediately after it has been set on the worker P. That is, the waist belt 71 and leg belts 75 are wrapped around and held by the worker P's waist Pw and thighs Pl, respectively, and the worker P is wearing a vest 80 around his or her upper body. The belt 40 extending from the reeling device R passes over the worker P's shoulders Ps, turns around there, and extends downward and forward, with the middle portion of the belt 40 passing through a rear belt guide 81r and a front belt guide 81f of the vest 80. At this time, the belt 40 is held in the initial withdrawn position, i.e., the standby position, and therefore the hook 20 (i.e., the fastener / connector) coupled to one end 40a of the belt 40 is also waiting in the initial position (the position in FIG. 9).

[0067] When the control device 55 of the automatic release command device 50 is activated from this standby state, the open / close switch 54 is turned on (therefore, the actuator 53 is energized) based on the detection result of the detection device 51 (for example, the mutual contact surface pressure and relative distance between the heavy load W and the hook 20 are not detected), thereby unlocking the locking mechanism 30, and in this state the retraction device R is free to both retract and pull out the belt 40 (see Figure 9). Then, as shown in Figure 10, the worker P grasps the base 20b or middle part of the hook 20 with his hand Ph and pulls out one end 40a of the belt 40 by an appropriate length.

[0068] Thus, with the middle portion of the belt 40 draped over the shoulder Ps, the worker P can grasp the hook 20 and pull out the belt 40 to the desired pull-out length that is optimal for engaging the heavy object W (the engaging hole 101 of the cardboard box 100), and in that pulled-out state, the hook portion 20at of the hook 20 held by the hand Ph can be easily and accurately engaged with the engaging hole 101 of the cardboard box 100, as is clear from Fig. 11. In this case, when the detector 51 detects a change in the relative distance before and after engagement, or a change in the contact surface pressure when the hand Ph of the worker P tries to grab and lift the heavy object W via the hook 20 after engagement, the controller 55 switches the open / close switch 54 to the OFF state (i.e., the actuator 53 to the non-energized state) based on the detection result, thereby causing the locking mechanism 30 to perform a locking operation.

[0069] 11, all that the worker P has to do is grasp the heavy load W with his / her hand Ph via the hook 20, and the heavy load W is suspended by the belt 40 hanging over his / her shoulder Ps, with the weight being borne not only by his / her arm Pa but also by his / her shoulder Ps and waist Pw. Therefore, by simply raising or moving his / her upper body while in this suspended state, the worker P can lift or hold the heavy load W more easily, which is to say, a work support effect can be expected.

[0070] Note that even during the above-described support work, the retraction of the belt 40 by the retractor R continues to be free (i.e., the locking mechanism 30 is locked only in the pull-out direction). For this reason, for example, if the worker P raises his / her hand Ph to a desired height while holding the heavy load W with the hand Ph as illustrated in Fig. 12, the belt 40 is automatically retracted by the retractor R by the amount of lift (i.e., the pull-out length of the belt 40 is adjusted to the shortened side), but because the locking mechanism 30 remains in the locked state, the pull-out of the belt 40 continues to be restricted.

[0071] Next, when the support work is completed and the worker P places the heavy load W at the destination, and at the same time, as shown in Figure 13, the hook 20 held by the hand Ph is released from the heavy load W (locking hole 101) and moved away from the heavy load W, the contact pressure between the heavy load W and the hook 20 suddenly decreases and the relative distance also changes suddenly. At this time, the detector 51 detects either of these changes and based on the detection result, the open / close switch 54 is turned on again (therefore, the actuator 53 is energized), thereby unlocking the locking mechanism 30, and the retraction device R becomes free to retract and pull out the belt 40.

[0072] Thus, when the worker P removes the hook 20 from the heavy load W by hand Ph, the belt 40 is automatically retracted to the standby position shown in Figure 9 by the retracting device R, and the hook 20 also returns to the standby position. When the control device 55 is deactivated, the operation of the work support device A is stopped.

[0073] As described above, the work support device A of this embodiment comprises an attachment part 10 that can be attached to the torso Pw of the worker P, a hook 20 (i.e., a locking device / connecting device) that can be attached to and detached from a heavy object W (more specifically, the locking hole 101 of the locked part / connected part) and that can be held by the worker P with his / her hand Ph, a belt 40 to which one end 40a of the hook 20 is connected, and a winding device R that is connected to the attachment part 10 and can wind up the other end of the belt 40, and the winding device R comprises a biasing mechanism 31 that applies a biasing force to the belt 40 in the winding direction, and a locking mechanism 30 that can lock the pull-out position of the belt 40 when one end of the belt 40 has been pulled out to an arbitrary pull-out length to restrict further pull-out.

[0074] As a result, by pulling out an appropriate length of one end of the belt 40 from the reeling device R fixed to the torso Pw side of the worker P and connecting the hook 20 to the heavy load W, and restricting further pulling of the belt 40 in this connected state with the locking mechanism 30, the worker P can transfer at least a portion of the load acting on the arm Pa or hand Ph to the torso Pw side through the belt 40 and the reeling device R when lifting or holding and moving the heavy load W, thereby reducing the burden on the worker P and effectively assisting and supporting the work. Moreover, since the hook 20 and the heavy load W are connected during the assisting work, there is no need for the worker P to continue to tightly grip the heavy load W with the hand Ph to prevent it from coming off. Therefore, fatigue in the hand Ph can be effectively reduced even during long hours of work, and there is no need to worry about the heavy load W dropping due to a decrease in grip strength.

[0075] Furthermore, the retractor R has a lightweight and simple structure that simply regulates the withdrawn length of the belt 40 with the locking mechanism 30, and thus achieves the above-mentioned work support effect, eliminating the need for a large rigid frame or an actuator for lifting luggage to be connected to the retractor R, thereby reducing costs and the burden on the worker P. Moreover, the retractor R is used exclusively to regulate the withdrawal of the belt during work, and can retract the belt 40 at any time during work, as well as before work begins and after work is completed. Therefore, there is no need to worry about the belt 40 interfering with normal operations when not working, or about other objects being inadvertently entangled in or wrapped around the belt 40, and the belt length can be adjusted without hindrance before work begins and during work.

[0076] Furthermore, since the hook 20 is connected to one end 40a of the belt 40, it can be placed in a standby state together with the belt 40 when not in use, so it does not get in the way and is easy to store and manage.

[0077] In another embodiment, the connecting device is a locking device (i.e., hook 20) ​​that can be locked to and released from a locking portion (i.e., locking hole 101) that serves as a connected portion provided on the heavy object W. This makes it possible to easily lock one end 40a of the belt to the heavy object W by simply hooking the hook 20 as a locking device onto the locking portion (locking hole 101) on the heavy object W side, which allows the connecting device to be handled more quickly and easily during support work, contributing to improved work efficiency.

[0078] In this case, the locked portion is a locking hole 101 provided in the heavy load W, and the locking device is a hook 20 having a hook portion 20at at its tip 20a that can be hooked into the locking hole 101, and one end 40a of the belt 40 is connected to the base 20b of the hook 20. As a result, in an embodiment in which the heavy load W is a heavy load body stored in a container with a locking hole 101, such as a cardboard box 100, or in a case in which the heavy load W itself originally has a locking hole 101 (not shown), the locking hole 101 that is originally present on the heavy load W side can also be used as the locked portion, which has the effect of further simplifying the locking structure between the belt 40 and the heavy load W, contributing to cost reduction and further improvement in workability.

[0079] Furthermore, in particular, the reeling device R of this embodiment is attached to the waist Pw of the worker P via the attachment portion 10 so that the middle portion of the belt 40 pulled out from the reeling device R can be slidably hung on the shoulders of the worker P, so that during the aforementioned work assistance, the reeling device R is connected and supported to the waist Pw of the worker P, while the middle portion of the belt 40 pulled out from the reeling device R passes over the shoulders Ps of the worker P, resulting in a unique support form in which a heavy load W is suspended via the hook 20 on one end of the belt 40. As a result, the reeling device R is located near the waist Pw, so that it does not get in the way of work, and furthermore, the gravity acting on the belt 40 during work assistance is received in a balanced manner, not only by the arms Pa of the worker P but also by the waist Pw, shoulders Ps, and the surrounding areas, thereby reducing the burden on the worker P.

[0080] Furthermore, since the locking mechanism 30 of the embodiment is connected to an unlock command device C for unlocking the locking mechanism 30 before and after work is started, the length of the belt 40 pulled out from the reeling device can be easily adjusted to any length by unlocking the locking mechanism 30 with the unlock command device before and after work is started. As a result, before and after work, the hook 20 at one end 40a of the belt 40 can be easily and accurately engaged with and disengaged from the heavy object W (retaining hole 101) and the hand Ph can support the heavy object W via the hook 20 held by the hand Ph without being hindered by the reeling device R.

[0081] In addition, the release command device C of the embodiment is an automatic release command device 50, which automatically unlocks the locking mechanism 30 before the start and after the end of the work based on the detection results of a detection device 51 that can detect changes in the contact pressure or relative distance between the hook 20 and the heavy object W before and after the start and end of the work to be supported, and also locks the locking mechanism 30 from the start to the end of the work.

[0082] The mounting unit 10 of the embodiment also includes a waist belt 71 that goes around the waist Pw of the worker P and is held at the waist Pw, and the reeling device R is connected to the waist belt 71. This allows the reaction force acting on the reeling device R when assisting with work such as lifting or holding a heavy load W to be dispersed over a wide area from the waist belt 71 to the waist Pw and its surroundings, thereby reducing the load on the waist Pw. Furthermore, the waist belt 71 applies an appropriate pressure to the abdomen, which increases intraperitoneal pressure and contributes to reducing the burden on the lumbar vertebrae.

[0083] Furthermore, in this embodiment, a leg belt 75 is connected to the waist belt 71, which can be attached to at least one of the thighs Pl of the worker P, so that the reeling device R itself can be prevented from slipping up when lifting a heavy object W, and the device R can be used effectively in an appropriate position.

[0084] Furthermore, the work support device A of the embodiment is provided with a vest 80 as work outerwear that can be worn by the worker P so as to cover at least the upper part of the shoulders Ps of the worker P, and the vest 80 is provided with belt guides 81f, 81r through which the belt 40 slidably passes so as to maintain the intermediate portion of the belt 40 in a state where it is hung on the shoulders Ps of the worker P. These belt guides 81f, 81r allow the belt 40 to be smoothly pulled out while accurately maintaining the intermediate portion of the belt 40 in a state where it is hung on the shoulders Ps of the worker P, thereby improving work efficiency.

[0085] 14 and 15 show essential parts of the second embodiment. In the first embodiment, the release command device C for unlocking the locking mechanism 30 is the automatic release command device 50 (i.e., the locking mechanism 30 is automatically unlocked before the start and after the end of the work to be supported based on the detection results of the detection device 51 capable of detecting changes in the contact surface pressure or relative distance between the hook 20 and the heavy load W before and after the start and end of the work to be supported), but in the second embodiment, the release command device C is a manual release command device 50' (i.e., the locking mechanism 30 is unlocked at any time based on an operation input to a release operation device that can be manually operated at will).

[0086] More specifically, the first example of the manual release command device 50' according to the second embodiment shown in Figure 14 (A) is similar to the automatic release command device 50 in that it comprises an operating cable 52 made of a Bowden cable with one end of an inner wire connected to the shaft 36a of the locking member 36, an electric actuator 53 which is interlocked and connected to the other end of the inner wire of the operating cable 52 and which can pull and drive the locking member 36 in the lock release direction (i.e., the unlocking direction of the lock mechanism 30) when current is applied, a normally open open / close switch 54 which opens and closes the current circuit of the actuator 53, and a control device 55 which controls the opening and closing of the open / close switch 54, but the control device 55 is designed to be able to link with a remote control device 56 which serves as a release operation device instead of the detection device 51 of the first embodiment.

[0087] The remote control device 56 can be easily operated by placing its operation unit in a location where it can be operated at any time by the worker P during work, or by carrying it with the worker P. The remote control device 56 may be configured to be linked to the control device 55 by wired or wireless communication means.

[0088] Thus, with this manual release command device 50', before the start and after the end of the work to be assisted, the worker P can release the remote control device 56 to turn on the open / close switch 54 (thus energizing the actuator 53), thereby unlocking the lock mechanism 30. On the other hand, from the start to the end of the work, the worker P can lock the lock mechanism 30 by releasing and turning off the remote control device 56 to turn off the open / close switch 54 (thus de-energizing the actuator 53).

[0089] 14(B) and 15 show a second example of a manual release command device 50'. In this second example, the remote control device 56 of the first example is omitted. Instead, as is clear from FIG. 15, an operation switch 58 that can be manually operated by the worker P while working is attached to the base 20b of the hook 20, and the operation switch 58 is connected to the control device 55 via the connection cord 28. The operation switch 58 controls the opening and closing of the opening / closing switch 54 based on an operation signal output to the control device 55 in response to an operation input to the operation switch 58, thereby opening and closing the current-carrying circuit of the actuator 53 as needed, thereby selectively unlocking and locking the locking mechanism 30. In this second example, the manually openable operation switch 58 constitutes the release operation device.

[0090] As can be seen in FIG. 15, an operation switch 58 is provided on the upper surface of the base 20b of the hook 20 (specifically, the horizontal plate portion 20bh), so that the worker P holding the hook 20 during work can easily operate the operation switch 58 with his / her hand Ph (for example, his / her thumb), thereby improving the operability of locking and unlocking the locking mechanism 30.

[0091] Although not shown, as a third example of the manual release command device 50' according to the second embodiment, it is also possible to implement a device in which the inner wire of the operating cable 52 is mechanically and directly pulled in the unlocking direction by a manually operable release operating lever at any time, thereby unlocking the lock mechanism 30. In this third example, not only can the control device 55, actuator 53, operating switch 58, and open / close switch 54 be omitted, but also the power supply can be omitted. Furthermore, the release operating lever functions as the release operating device.

[0092] In this third example, if a holding mechanism is attached to the release operating lever, which can hold the release operating lever at any time in the tractive drive position relative to the inner wire of the operating cable 52 (and therefore the lock mechanism 30 in the unlocked position), the release operating lever can be held in the tractive drive position for any period of time even when the release operating lever is released after tractive drive. In this case, the lock mechanism 30 can be switched to the locked operating position by releasing the operation of the holding mechanism at any time.

[0093] In the above description of each example of the second embodiment, only the characteristic parts that are different from the first embodiment have been described, but the other configurations of the second embodiment are basically the same as those of the first embodiment. Therefore, the components of the second embodiment are simply given the same reference numerals as the corresponding components of the first embodiment, and further specific description will be omitted.

[0094] Therefore, in this second embodiment, it is possible to achieve basically the same effects as those of the first embodiment, except that the switching of the release command device C for unlocking the lock mechanism 30 is performed based on manual operation of the release operation device (i.e., the remote control device 56).

[0095] In particular, in the first to third examples of the manual release command device 50' according to the second embodiment, the lock mechanism 30 can be unlocked at any time based on an operation input to a manually operable release operation device (remote control device 56, operation switch 58, release operation lever). Therefore, for example, before the start or after the end of the work to be assisted, the worker P can unlock the lock mechanism 30 by operating the release operation device, and on the other hand, between the start and end of the work, the lock mechanism 30 can be locked by operating the release operation device to release / off.

[0096] 16 shows a front view and a rear view illustrating a state in which a work support device A according to the third embodiment is in use. That is, in the first and second embodiments, a pair of left and right reeling devices R, R are arranged in parallel at a distance from each other on the back side of the worker P, and a belt 40 is pulled out from each of the reeling devices R, and a hook 20 serving as a connector / locking device is connected to each end 40a of the belt 40, whereas in the third embodiment, only one reeling device R is provided on either the left or right side, and the belt 40 pulled out from that reeling device is also hung around the shoulder Ps on that side of the worker P and connected to the hook 20 on that side.

[0097] The other configurations of the third embodiment are similar to those of the first and second embodiments, so each component of the third embodiment is simply given the same reference numeral as the corresponding component of the first and second embodiments, and further explanation will be omitted.

[0098] The third embodiment also achieves basically the same effects as the first and second embodiments, but in the second embodiment in particular, a single winding device R is used, which reduces costs. However, on the other hand, the assisting force exerted by the work support device A on the worker P when lifting a heavy object is halved, so the worker P must directly support the other side of the heavy object W to be lifted with his or her hand Ph. Therefore, this is effective when the weight is relatively small (for example, when lifting a small package with one hand).

[0099] 17 shows a front view and a rear view illustrating a usage state of a work support device A according to a fourth embodiment. In this fourth embodiment, a single reeling device R is used, but the belt 40 pulled out from it has a bifurcated portion 40j that branches into two midway (particularly on the back side). As in the first embodiment, a pair of left and right belts 40 branching and extending from the bifurcated portion 40j are hung on the left and right shoulders Ps of the worker P, and a hook 20 is further connected to each end 40a of the left and right belts 40.

[0100] The other configurations of the fourth embodiment are similar to those of the first and second embodiments, so each component of the fourth embodiment will be given the same reference numeral as the corresponding component of the first and second embodiments, and further explanation will be omitted.

[0101] The fourth embodiment also achieves basically the same effects as the first and second embodiments, but in particular, the fourth embodiment not only requires a single winding device R, but also reduces the amount of belt 40 used from the winding device R to the branch portion 40j, thereby achieving cost savings.

[0102] 18 shows variations of the leg belt 75, in particular (A) showing a leg belt that wraps around the thigh diagonally (corresponding to the first and second embodiments), and (B) showing a leg belt 75 that wraps around the thigh approximately horizontally. The leg belt 75 of (B) differs from the leg belt 75 of the first and second embodiments only in the way it wraps around the thigh P1, but can basically achieve the same effects as the first and second embodiments.

[0103] Furthermore, Fig. 19 shows a first modified example of the first and second embodiments in which the reeling device R is disposed on the side of the waist region Pw, and Fig. 20 shows a second modified example of the first and second embodiments in which the reeling device R is disposed in front of the waist region Pw. These modified examples can also basically achieve the same effects as the first and second embodiments.

[0104] In the above-described embodiments and their modified examples, an example of a connecting structure for detachably connecting one end 40a of the belt 40 to the heavy object W is given, in which the hook 20 on the belt 40 side is hooked into the engaging hole 101 (engaged portion / connected portion) on the heavy object W side, but the connecting structure is not limited to the embodiments and their modified examples.

[0105] For example, in the first modified example of the connecting structure illustrated in Figure 21 (A), a structure is shown in which the relationship between the hook 20 and the locking hole 101 (locked portion) is reversed, that is, a hook-shaped member Wf with a downward hook portion that serves as the locked portion / connected portion is arranged on the heavy object W side, and an engaging member 201 with a locking hole 201h that serves as the locking device / connecting device is arranged on one end 40a side of the belt 40, and the engaging member 201 is detachably locked to the hook-shaped member Wf, i.e., connected, and this variation also shows a variation in which the same effect as the above embodiment can be achieved.

[0106] In addition, in the second modified example of the connecting structure illustrated in Figure 21 (B), the shaft portion 202j of the connecting member 202 as a connecting device connected to one end 40a of the belt 40 is detachably secured to a connected portion fixed on the heavy load W side (for example, a bracket 120 with an engagement hole 120h into which the shaft portion 202j is inserted) by a stopper (for example, a snap pin 130 that can be engaged with the shaft portion 202j to prevent it from coming loose) that engages the shaft portion 202j and the bracket 120 with each other, i.e., a variation is shown in which the shaft portion 202j is detachably secured to, i.e., connected to, a connected portion fixed on the heavy load W side (for example, a bracket 120 with an engagement hole 120h into which the shaft portion 202j is inserted) by a stopper (for example,

[0107] The fastener is not limited to the snap pin 130, but may be, for example, a circlip that can be engaged with the outer periphery of the shaft portion 202j.

[0108] In addition, in the third modified example of the connecting structure illustrated in Figure 21 (C), the shaft portion 202j of the connecting member 202 serving as a connecting device joined to one end 40a of the belt 40 is detachably screwed, i.e., connected, to a connected portion fixed to the heavy load W side (for example, a bracket 120 with an engagement hole 120h into which the shaft portion 202j is inserted) with a butterfly nut 140 threaded onto the shaft portion 202j, and this variation can also achieve basically the same effects as the above embodiment.

[0109] In addition, in a fourth modified example of the connecting structure illustrated in Figure 21 (D), a connecting device 203 connected to one end 40a of the belt 40 has a powerful permanent magnet 203m fixed to the bottom, and this variation shows a variation in which the connecting device 203 is detachably attracted to, i.e., connected to, a connected part (e.g., magnetic member 150) fixed on the heavy object W side by the magnetic force of the permanent magnet 203m, and this variation also achieves basically the same effect as the above embodiment.

[0110] Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various design modifications can be made without departing from the present invention as set forth in the claims.

[0111] For example, in the above embodiment, the worker P himself performs the operation of pulling out the belt 40 from the reeling device R, but a person other than the worker P may perform the pulling operation and assist in engaging the hook 20 connected to one end 40a of the belt 40 with the engaging hole 101 of the heavy object W.

[0112] In particular, in the first embodiment, the release command device C is shown to be an automatic release command device 50 that automatically unlocks the locking mechanism 30 in response to a determination that work has not yet started or has finished based on the detection result of the detection device 51, and in the second embodiment, the release command device C is shown to be a manual release command device 50' that manually unlocks the locking mechanism 30 in response to an operation input to any manually operable release operation device (remote control device 56, operation switch 58, release operation lever, etc.), but the present invention may also be a work support device that includes both the automatic release command device 50 and the manual release command device 50' as the release command device C.

[0113] In addition, in the first embodiment, the detection device 51 (i.e., the surface pressure sensor 51A, the proximity sensor 51B) linked to the automatic release command device 50 is capable of detecting changes in the contact surface pressure or relative distance between the hook 20 and the heavy object W before and after the start and before and after the end of work, and based on the detection results, the control device 55 determines that the work has started or ended and unlocks the locking mechanism 30. However, the detection device 51 is not limited to the embodiment and can be applied as long as it can detect any change in the work state before and after the start and before and after the end of work.

[0114] In addition, in the above embodiment, the power source of the biasing mechanism 31 of the retractor R is the spiral spring 32, and the spring force is used as the retraction biasing force, but an electric motor may be used as the power source of the biasing mechanism 31. However, even in this case, the retractor R is used only to retract the belt 40, and there is no need to rotate or pull up a sturdy, heavy rigid frame as in the above patent document, so a motor with a relatively small output can be used, and cost increases can be suppressed.

[0115] In the above embodiment, a vest 80 is used as work outerwear that can be worn by the worker P so as to cover at least the upper part of the shoulders Ps of the worker P, and the vest 80 is provided with belt guides 81f, 81r through which the belt 40 slidably passes to maintain the intermediate portion of the belt 40 hanging over the shoulders Ps of the worker P. However, the vest 80 as work outerwear is not essential to the work support device A of the present invention. For example, a worker P wearing ordinary clothes without wearing the vest 80 may have the intermediate portion of the belt 40 slidably hang directly over the shoulders Ps. Alternatively, an outerwear style other than the vest 80 (e.g., a blazer or a shirt) may be used as the work outerwear of the present invention, and the belt guides 81f, 81r may be provided on the front and back of the outerwear.

[0116] In addition, in the above embodiment, the retracting device R is shown as being attached to the waist Pw of the worker P via the attachment part 10 including the waist belt 71, but the attachment location of the retracting device R is not limited to the embodiment, and the retracting device R may be attached to a part of the torso Pm other than the waist Pw (for example, the shoulder Ps, the back, etc.). In particular, when the retracting device R is attached to the shoulder Ps, it is not necessary to hang the middle part of the belt 40 pulled out from the retracting device R around the shoulder Ps of the worker P.

[0117] In the above embodiment, the heavy load W is shown as an assembly of a heavy load main body (not shown) and a container (i.e., cardboard box 100) that houses it, but the configuration of the heavy load W is not limited to the embodiment, and for example, the heavy load W may be a heavy load main body that is not housed in a container (and therefore exposed to the outside). In this case, the outer wall of the heavy load main body is provided with something that functions as a locked portion or a connected portion (something that can perform the same function as the locking hole 101, hook-shaped member Wf, bracket 120, and magnetic member 150 described in the above embodiment or modified example).

[0118] A... Work support device C... Release command device P... Worker Pa, Pf, Ph, Pl... Worker's arms, fingers, hands, thighs Pm, Ps, Pw... Worker's torso, shoulders, waist R... Winding device W... Heavy object Wf... Hook-shaped member as locked part 10... Mounting part 20... Hook as locking device / connector 30... Locking mechanism 31... Urging mechanism 40... Belt 40a... One end part 40j... Branch part 50... Automatic release command device 50'... Manual release command device 51... Detection device 51A... Surface pressure sensor which is a first example of a detection device 51B... Proximity sensor which is a second example of a detection device 56... Remote control device as a release operation device 58... Operation switch as a release operation device 71... Waist belt 75... Leg belt 80... Vest as work outerwear 81f, 81r... Front and rear belt guides as belt guides 100... Cardboard box as a container for accommodating a heavy object body 101... Locking hole as a locked portion / connected portion 120... Bracket as a connected portion 150... Magnetic member as a connected portion 201... Engaging member with locking hole as a connecting tool 202... Connecting member as a connecting tool 203... Connecting tool with permanent magnet

Claims

1. A work support device that assists a worker (P) in lifting and holding a heavy object (W), comprising: an attachment part (10) that can be attached to the torso (Pm) of the worker (P); connectors (20, 201-203) that can be attached to and detached from connected parts (101, Wf, 120, 150) provided on the heavy object (W) and that can be held by the hand of the worker (P); a belt (40) to one end (40a) of which the connectors (20, 201-203) are connected; and a winding device (R) that is connected to the attachment part (10) and can wind up the other end of the belt (40); The winding device (R) is a work support device characterized in that it is equipped with a biasing mechanism (31) that applies a biasing force in the winding direction to the belt (40), and a locking mechanism (30) that can lock the pull-out position of the belt (40) when the one end (40a) of the belt (40) is pulled out to an arbitrary pull-out length so as to restrict further pull-out.

2. The work support device as described in claim 1, characterized in that the connecting device is a locking device (20) that can be locked to and released from a locking portion (101, Wf) serving as the connected portion provided on the heavy object (W).

3. The work support device according to claim 2, characterized in that the engaged portion is a locking hole (101) provided in the heavy object (W), the locking device is a hook (20) having a hook portion (20at) at a tip portion (20a) capable of being hooked into the locking hole (101), and the one end portion (40a) of the belt (40) is connected to a base portion (20b) of the hook (20).

4. A work support device as described in claim 1 or 2, characterized in that the winding device (R) is attached to the waist (Pw) of the worker (P) via the mounting portion (10) so that the middle portion of the belt (40) pulled out from the winding device (R) is slidably hung on the shoulder (Ps) of the worker (P).

5. A work support device as described in claim 1, characterized in that the locking mechanism (30) is connected to an unlocking command device (C) for unlocking the locking mechanism (30) before the start of the work and after the end of the work.

6. The work support device according to claim 5, characterized in that the release command device (C) includes at least one of an automatic release command device (50) which automatically releases the locking mechanism (30) before the start and after the end of the work based on the detection results of a detection device (51) capable of detecting changes in contact pressure or relative distance between the connector (20, 201-203) and the heavy load (W) before and after the start and after the end of the work, or a manual release command device (50') which releases the locking mechanism (30) as needed based on an operation input to a release operation device (56, 58) which can be manually operated at will.

7. The work support device according to claim 1 or 2, characterized in that the connector (20, 201-203) can be held in the hand (Ph) of a worker (P) and its posture can be controlled while the connector (20, 201-203) is connected to the connected portion (101, Wf, 120, 150).

8. A work support device as described in claim 1 or 2, characterized in that the attachment portion (10) includes a waist belt (71) that goes around the waist (Pw) of the worker (P) and is held at the waist (Pw), and the winding device (R) is connected to the waist belt (71).

9. A work support device as described in claim 8, characterized in that a leg belt (75) that can be attached to at least one of the thighs (Pl) of the worker (P) is connected to the waist belt (71) and passed around the thigh (Pl).

10. A work support device as described in claim 1 or 2, characterized in that the belt (40) has a branched portion (40j) that branches into two midway from the other end side toward the one end (40a).

11. A work support device as described in claim 1 or 2, further comprising a work jacket (80) that can be worn by the worker (P) so as to cover at least the upper part of the shoulders (Ps) of the worker (P), the jacket (80) being provided with belt guides (81f, 81r) through which the belt (40) can slide so as to maintain the middle portion of the belt (40) hanging over the shoulders (Ps) of the worker (P).

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