JP3974159B1 - Lifting aid - Google Patents

Abstract

An object of the present invention is to provide a lifting assist device capable of reducing the burden on an operator when moving an object greatly and having excellent durability.
SOLUTION: It becomes a stationary node of a four-bar linkage mechanism set up in a vertical direction, one connecting point P is in the upper vertical direction, and the other connecting point Q is in the lower vertical direction, and has a stable posture on the horizontal plane. A leg 2 that can be taken, a waist 3 that forms a pair that turns around the leg at the connection point P, a first lever 7 that forms a pair that turns around the leg at the connection point Q, and the link mechanism The second lever 8 serving as an intermediate node between the waist and the first lever, and the first lever is driven to rotate around the connection point Q by being fixed to the leg, or the waist and the second are fixed to the waist. A motor 4 that rotationally drives the second lever around a connection point S with the lever, a spine that extends upward from the waist, and an arm 6 that is rotatably connected to the upper end of the spine in a vertical plane. It is characterized by.
[Selection] Figure 1

Description

  The present invention relates to a lifting assist device for assisting an operator in lifting an object, and can be suitably used as a nursing assist device particularly when a caregiver lifts a cared person.

  When caring for a bedridden elderly person or patient (hereinafter referred to as a cared person), the cared person may need to be lifted, which places a great physical burden on the carer. Moreover, not only such a nursing care site but the work which lifts a heavy object will cause injury, such as a waist member pain. Therefore, various devices for assisting such lifting work have been proposed. Of these types, the type that assists the operator's movement following the posture of the operator is generally smaller in installation area and easier to operate than the type that suspends from the frame provided above the bed. Moreover, it is preferable in that it gives a sense of security to the care recipient.

Conventionally, as a lifting assist device such as a care assist device, Patent Document 1 discloses a structure using an elastic body or a fluid pressure cylinder that contracts by applying pressurized fluid to a drive source for returning from a forward tilt posture to an upright posture. is doing. Patent Document 2 discloses a structure that raises and lowers an arm with rotation of a screw shaft driven by a motor. Patent Document 3 discloses a structure in which a motor is connected to the original section of two sets of parallel links connected vertically. Patent Document 4 discloses a structure in which an arm is swung by the tension of a winding wire driven by a motor.
Japanese Patent Laid-Open No. 03-165765 Japanese Patent Laid-Open No. 11-309184 JP 2000-84012 A JP 2000-70312 A

However, in spite of the main movement of the operator during the lifting operation being the rotation of the spine member around the waist member, the device described in Patent Document 1 is such that the output of the drive source moves linearly. For this reason, the forward tilt range of the spine member is limited, and the object cannot be moved greatly, and the drive source is overpowered and is prone to failure at an early stage. Apparatus according to Patent Document 2, the first place does not correspond to the anteversion posture of the spine member. Those devices described in Patent Document 3, to reduce the burden on any motor also merely driving source for bending and stretching the parallel link following the bending of the leg member, the spine member in returning to the upright from anteversion Not. The device described in Patent Document 4 is unrealistic because the winding wire is likely to break.
Therefore, an object of the present invention is to provide a lifting assist device that can reduce the burden on an operator when moving an object greatly and is excellent in durability.

In order to solve the problem, the lifting assist device of the present invention includes:
A lifting assist device for assisting an operator in lifting an object,
A leg member that becomes a stationary node of a four-link mechanism standing in the vertical direction, and has one connecting point P in the upper vertical direction and the other connecting point Q in the lower vertical direction, and can take a stable posture on the horizontal plane. When,
A waist member which is one node that turns around the leg member at the connection point P;
A first lever, which is another node that turns around the leg member at the connection point Q;
A second lever serving as an intermediate node between the waist member and the first lever in the link mechanism;
Or a first lever rotatably driven around the connecting point Q is fixed to the leg member, or a motor of the second lever is driven to rotate is fixed to the waist member around the connecting point S between the waist member and the second lever When,
A spine member that extends upward and continues to the waist member ;
And an arm member rotatably connected to the upper end of the spine member in a vertical plane.

That is, as schematically shown in FIG. 1, the leg member L has an appropriate shape that can take a stable posture on a horizontal plane, and has a connecting point P at an appropriate upper position and a connecting point Q at a lower position. A waist member W is connected to the connection point P, a first lever F is rotatably connected to the connection point Q, and the second lever M is connected to the other connection point S of the waist member W and the other connection point R of the first lever F. Tied. This constitutes a four-joint link mechanism in which the PQRS is a stationary joint between the PQRS, and the other two joints are constant according to the movement of any one of the waist member W, the first lever F, and the second lever M. Make a move. An unillustrated motor is fixed to the waist member W, and the second lever M rotates around the connection point S by the output thereof, and the waist member W and the first lever F are accompanied by the rotation.

The spine member B is connected to the waist member W, and a large load is applied. However, the spine member B can be tilted forward as shown by an imaginary line with a small torque using the connecting point P as a fulcrum. The same applies when returning from the forward leaning posture to the upright posture. The output of the motor may be directly connected to the connection point S or via a gear. In any case, the movement of each element from the drive source to the arm member as the action point is all rotational movement. Therefore, there is little friction between the power transmission mechanism and the joint, and the whole is sturdy. If the distance between the PSs is increased, the rotation angle of the waist member is reduced and the operating range of the arm member is narrowed, but a larger load can be supported. On the other hand, if the distance between the PSs is shortened, the load that can be supported is reduced, but the operating range of the arm member can be further expanded.

The motor may be fixed to the leg member L and rotationally drive the first lever around the connection point Q. However, the fixed volume to the waist member W as shown in FIG. This is preferable because the motor position is high, and contamination of the motor with dust can be suppressed. When fixed to the waist member W, it is preferable that the first lever F has a length that is at least twice that of the second lever M because each node moves smoothly.

One preferred configuration for the arm member is:
A shoulder member connected to the upper end of the spine member and extending rearward;
The upper arm portion extending downward from the end portion of the shoulder member , and the forearm portion that is hinged to the lower end of the upper arm portion and extends forward longer than the shoulder member ,
The forearm is restricted by the ratchet wheel mechanism in the direction in which the angle with the upper arm increases.
Extending shoulder member rearward, since the forearm extends forwardly longer than the shoulder member, whole arm member is dynamically balanced with the upper end of a rear portion and a front portion of the spine member, before if there in an upright position regardless to be inclined posture, forearms keeping the substantially horizontal, it is possible to place the object. Since the arm member is rotatable with respect to the spine member , the center of the combined weight of the object and the arm member as the user tries to return to the upright position to lift after placing the object in the forward leaning posture. Also move backwards. Therefore, it will not fall down.

Another preferred structure for the arm member is
A shoulder member connected to the upper end of the spine member and extending rearward;
An upper arm portion that is fixed to the end of the shoulder member so as to be rotatable about an axis that is in a torsional position relative to the rotation axis of the shoulder member , and extends downward;
The forearm portion is hinged to the lower end of the upper arm portion and extends forward longer than the shoulder member , and is fixed to the upper arm portion, and includes a power source that rotates the forearm portion relative to the upper arm portion.
Since the forearm portion is rotated by a power source with respect to the upper arm portion, the forearm portion can be fixed at an angle at which an object can be easily placed.

In any case, it is more preferable that the forearm portion has one or more joints. This is because the object can be stabilized by bringing the forearm along the shape of the object to be lifted.
In the latter of the two preferable configurations of the arm member , it is particularly preferable to connect the appropriate position of the shoulder member and the appropriate position of the leg member with a single support rod.

  As described above, the device of the present invention can extract a large force from a small driving source by the action of the link mechanism, and all the movements of the elements are rotational movements, and the friction of the power transmission mechanism and the joint is small. The whole is sturdy. Therefore, it has the advantages of both the hanging type and the lifting type, and the burden on the operator can be reduced when moving a heavy object greatly.

Embodiment 1
A lifting assist device according to a first embodiment of the present invention will be described with reference to the drawings. 2 is a front view showing an embodiment of the lifting assist device, FIG. 3 is a right side view, and FIG. 4 is a front view showing the operating state. The rear view appears almost symmetrically with the front view.

The lift assisting device 1 (hereinafter referred to as “device 1”) assists the caregiver's lifting force when the caregiver lifts the cared person. Be behind. Hereinafter, unless otherwise specified, the left side is the front and the right side is the rear.
The apparatus 1 includes a leg member 2 composed of a right-angled opposite side of a non-isosceles right-angled triangle and the other side of the shorter side, a waist member 3 rotatably fixed to the leg member 2, a motor 4, and a waist member 3. The spine member 5 and the two arm members 6 and 6 which are connected integrally are provided.

The leg member 2 includes a rear leg portion 2a that is vertically formed in a rectangular shape when viewed from the right side, and front leg portions 2b and 2b that land while extending forward from the upper ends on both sides in the width direction of the rear leg portion 2a. Become. The front leg 2b corresponds to the opposite side of the right triangle and the rear leg 2a corresponds to the other side. Casters 2c are attached to the lower ends of both sides in the width direction of the rear leg 2a and the lower ends of the front legs 2b. In addition, first levers 7 and 7 are attached to the center of the lower side (connection point Q) of the rear leg 2a so as to be rotatable in a vertical plane with a space therebetween.

The waist member 3 has a plate shape, and its rear end is fixed to a rotating shaft 3a (connection point P) that crosses between the front leg portions 2b and 2b in the vicinity of the upper end of the front leg portion 2b. The motor 4 is fixed at the center of the lower surface of the waist member 3. The output of the motor 4 is equally divided on both sides of the motor 4 by gears (not shown) mounted on the output shaft and bevel gears 4a and 4a meshing with the gears. And the 2nd levers 8 and 8 are attached on the rotating shafts 3a and 3a (connection point S) of the bevel gears 4a and 4a. The free end (connection point R) of each second lever 8 is connected to the free end (connection point R) of the first lever 7. The first lever 7 has a length 2.5 times that of the second lever 8. The spine member 5 has two pillars 5a and 5a that are erected on both sides of the upper surface of the waist member 3, and a U-shaped frame 5b that is fixed upward at the upper end and has a width wider than the distance between the pillars 5a and 5a. It consists of.

Arm members 6,6 are each mounted rotatably about an axis parallel to the rotation shaft 3a on both sides of the upper end of the frame 5b, a shoulder member 6a extending backward from point of attachment to the frame 5b, the shoulder member 6a An upper arm portion 6b extending downward from the end portion of the upper arm portion 6b and a forearm portion 6c hinged to the lower end of the upper arm portion 6b and extending forward. The forearm 6c has three joints from the connection point with the upper arm 6b to the wrist 6d at the tip, and each joint has a small angle with the upper arm 6b as shown in FIG. The rotation in the direction to be free is allowed, and the rotation in the direction to increase is allowed only when the pawl (not shown) of the ratchet wheel mechanism is released. The length of the forearm portion 6c is 3 to 4 times that of the shoulder member 6a.

In the device 1, the leg member 2, the waist member 3, the second lever 8, and the first lever 7 constitute a four-joint link mechanism in a vertical plane. That is, a stationary node is formed between the connection points PQ in the leg member 2, a node that rotates between the connection point PS in the waist member 3 and the motor 4 integrated therewith and a stationary node, and a first lever 7 is rotated with the stationary node to form a pair. Another lever, a four-bar lever crank mechanism having the second lever 8 as an intermediate bar, is constructed.

When the caregiver lifts a bedridden person who is bedridden, for example, using the apparatus 1, the caregiver stands between the front legs 2 b and 2 b and turns on the motor 4. Then, as shown by an imaginary line in FIG. 4, the second lever 8 rotates around the connection point S by the output of the motor 4, and the waist member 3 and the first lever 7 are accompanied by it. At the same time, the spine member 5 tilts forward, and the arm member 6 is displaced downward. After inserting the hand 6d under the cared person and placing the cared person on the hand 6d, the motor 4 is reversed. The spine member 5 tries to return to the upright posture, and accordingly the forearm portion 6c horizontally moves backward. Therefore, the center of gravity of the entire arm member 6 on which the cared person is placed also moves rearward and does not fall down. When the spine member 5 further rises, the forearm 6c rises and lifts the cared person.

Since the spine member 5 is swung on the principle of the lever with the rotating shaft 3a as a fulcrum, the torque of the motor 4 is sufficient. In addition, the movement of each element from the motor 4 to the arm member 6 is all rotational movement. Therefore, there is little friction between the power transmission mechanism and the joint, and the whole is sturdy. Further, since the motor 4 is fixed to the lower surface of the waist member 3, the motor 4 is almost contained in a space surrounded by the front legs 2 b and 2 b and the rear leg 2 a, and the occupied volume of the entire apparatus 1 is increased due to the presence of the motor 4. It is not necessary, and the motor position is high, so that contamination of the motor with dust can be suppressed.

Embodiment 2
6 is a front view showing a second embodiment of the lifting assist device, FIG. 7 is a right side view, and FIG. 8 is a front view showing the operating state. The rear view appears almost symmetrically with the front view. In the lifting assist device 11 of this embodiment, the structure and movement of the arm member 16 are different from those of the arm member 6 in the first embodiment. Since the other points are the same as those of the first embodiment, the description is omitted and only the same reference numerals are used. Hereinafter, differences from the first embodiment will be described in detail.

The arm members 16, 16 are respectively attached to the upper ends on both sides of the frame 5b so as to be rotatable about an axis T parallel to the rotation shaft 3a, and have a shoulder member 16a, an upper arm portion 16b, and a forearm portion 16c. The shoulder member 16a extends rearward from the connection point with the frame 5b, and has a plate shape that becomes wider in the vertical direction toward the rear. Upper arm 16b is rotatably secured to the end of the collar member 16a about an axis 16e in a positional relationship twisted between the rotation axis T of the shoulder member 16a, and extends downward. A motor 9 having an output shaft substantially parallel to the shaft 16e is fixed to the upper arm portion 16b. The forearm portion 16c is hinged to the lower end of the upper arm portion 16b and extends forward. The forearm portion 16c has the same shape as the forearm portion 6c of the first embodiment except that the worm gear 16f is provided at the joint portion with the upper arm portion 16b. The worm gear 16 f meshes with the worm 16 g on the output shaft of the motor 9.

On the other hand, one end of each of support rods 10 and 10 is rotatably connected to the vicinity of both ends U and U on the upper side of the rear leg 2a. The other end of the support bar 10 is connected to the rear upper end V of the shoulder member 16a. Therefore, the support bar 10 constitutes another four-bar linkage mechanism with the leg member 2, the waist member 3, the spine member 5, and the shoulder member 16 a as a stationary node between the UPs in the leg member 2. For this reason, the shoulder member 16a draws a trajectory determined by the angles of the spine member 5 and the support bar 10 regardless of whether the object to be lifted is placed on the hand 16d. However, the forearm portion 16 c can swing in the vertical direction as shown in FIG. 9 according to the output of the motor 9.

Even when a caregiver using a device 11 for lifting the bedridden person cared for example the bed, as in the embodiment 1, and inclined forward is the spine member 5 at the output of the motor 4 as shown in phantom in FIG. 8, the arm The member 16 is displaced downward. The hand 16d is inserted under the cared person and the cared person is placed on the hand 16d. The forearms 16c and 16c are expanded or narrowed with the shaft 16e as a fulcrum according to the height of the cared person, and then the motor 4 is reversed. The spine member 5 tries to return to the upright posture, and accordingly the forearm portion 6c horizontally moves backward. Therefore, the center of gravity of the entire arm member 6 on which the cared person is placed also moves rearward and does not fall down. When the spine member 5 further rises, the forearm portion 16c rises and lifts the cared person. In the middle, the motor 9 is turned on according to the weight and body shape of the cared person, and the forearm portion 16c is swung with respect to the upper arm portion 16b to keep the forearm portion 16c horizontal.

  According to the device 11, in addition to producing the same effects as in the first embodiment, the weight of the care recipient is supported at two points of the connection point P and the connection point U. Person can be lifted.

It is a schematic diagram which shows the effect | action of a lifting assistance apparatus. It is a front view showing an embodiment of a lifting auxiliary device. Same right side view It is a front view which similarly shows an operation state. It is a front view which shows the motion of the joint of the arm member of the apparatus. It is a front view which shows 2nd embodiment of a lifting assistance apparatus. Similarly, it is a right side view. It is a front view which similarly shows an operation state. It is a front view which shows the motion of the forearm part of the apparatus.

Explanation of symbols

1, 11 Lifting auxiliary device 2 Leg member 3 Waist member 4 Motor 5 Spine member 6, 16 Arm member

Claims (7)

A lifting assist device for assisting an operator in lifting an object,
A leg member that becomes a stationary node of a four-link mechanism standing in the vertical direction, and has one connecting point P in the upper vertical direction and the other connecting point Q in the lower vertical direction, and can take a stable posture on the horizontal plane. When,
A waist member which is one node that turns around the leg member at the connection point P;
A first lever, which is another node that turns around the leg member at the connection point Q;
A second lever serving as an intermediate node between the waist member and the first lever in the link mechanism;
Or a first lever rotatably driven around the connecting point Q is fixed to the leg member, or a motor of the second lever is driven to rotate is fixed to the waist member around the connecting point S between the waist member and the second lever When,
A spine member that extends upward and continues to the waist member ;
A lifting assist device comprising: an arm member rotatably connected to an upper end of a spine member in a vertical plane. The motor, raising assist device according to claim 1 for rotating the second lever as a rotation center connecting point S between the waist member and the second lever is fixed to the waist member.   The lifting assist device according to claim 2, wherein the first lever has a length twice or more that of the second lever. The arm member is
A shoulder member connected to the upper end of the spine member and extending rearward;
The upper arm portion extending downward from the end portion of the shoulder member , and the forearm portion that is hinged to the lower end of the upper arm portion and extends forward longer than the shoulder member ,
The lifting assist device according to claim 1, wherein the forearm portion is restricted from moving in a direction in which an angle with the upper arm portion is increased by a ratchet wheel mechanism. The arm member is
A shoulder member connected to the upper end of the spine member and extending rearward;
An upper arm portion that is fixed to the end of the shoulder member so as to be rotatable about an axis that is in a torsional position relative to the rotation axis of the shoulder member , and extends downward;
The lifting assist according to claim 1, comprising a forearm portion that is hinged to the lower end of the upper arm portion and extends forward longer than the shoulder member , and a power source that is fixed to the upper arm portion and that rotationally drives the forearm portion relative to the upper arm portion. apparatus.   The lifting assist device according to claim 4 or 5, wherein the forearm portion has one or more joints. The lifting assist device according to claim 5, further comprising a support bar connected between the shoulder member and the leg member .

Images