JPH10218588A - Working arm balancer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a working arm balancer capable of suppressing fluctuation of its auxiliary force to swing an associated working arm up or down and of controlling the auxiliary force with a simple structure. SOLUTION: A working arm balancer comprises a derricking arm 34, a roller 39 arranged in the arm 34 so as to freely slide thereon in the same direction where the arm 34 extends, a link member 37, and a gas spring 38 for applying auxiliary force to the arm 34 to swing it up. The link member 37 is pivoted at its tip on the roller 39 and at its base on a base member 31. The gas spring 38 is also pivoted at its tip on the roller 39 and at its base on the base member 31 so as to apply auxiliary force to the arm 34 to swing it up against the load acting on the arm 34 to fall it down.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a work arm balance device used for a work arm for assisting a worker by attaching a work device to a distal end.

[0002]

2. Description of the Related Art When power distribution work is carried out on an upper part of a power pole, a boom is provided on a vehicle body so that the boom can be moved up and down and extended, and a worktable on which a worker can ride is provided at a tip of the boom. Work vehicles are used. Further, a work arm is often provided on the work table for the purpose of safely performing construction (so-called “hot-line construction”) in a state where power is supplied to the power distribution equipment and reducing the labor of the operator.

The working arm has a detachable working device such as a hot stick at the tip. Further, formed by a plurality of arm members so that these working devices can be moved to a desired working position,
Each arm member is configured to be able to freely move up and down and rotate horizontally.

When the arm member is configured to be able to move up and down with respect to the work table and other arm members, the arm is raised and lowered so that the operation of raising and lowering the arm and holding at a desired position can be easily performed. Provide a balancer (balance device). The undulating balancer is a gas spring (gas cylinder)
Alternatively, an auxiliary force applying means such as a coil spring is provided, and an auxiliary force for raising the undulating arm against a load acting in a direction in which the undulating arm is lowered is applied.

[0005]

Here, when the assisting force applying means for applying the assisting force is arranged so as to push up the arm from below, the assisting force applying means generates a repulsive force in accordance with the expansion and contraction operation. Change. That is, when the gas spring or the like is compressed and contracted (the arm is lying down), the force for raising the arm acts greatly,
In a state where the arm is extended (the arm is raised), the force for raising the arm acts small, and there is a problem that the assisting force becomes uneven.

[0006] The weight of the working device attached to the tip of the working arm varies depending on its type. For this reason, when the assisting force in the undulating balancer is constant, there is also a problem that the assisting force becomes excessive or insufficient depending on the working device to be mounted.

SUMMARY OF THE INVENTION The present invention has been made in view of such a problem, and it is possible to reduce the change of the assisting force at the time of the undulating operation, and to adjust the assisting force with a simple configuration. It is an object of the present invention to provide a balance device for an arm for use.

[0008]

In order to achieve the above object, a working arm according to the present invention comprises an up-and-down arm and an up-and-down arm slidably in an axial direction which is the same as the direction in which the up-and-down arm extends. , A link member, and an auxiliary force applying means for applying an auxiliary force for raising the raising / lowering arm.

The working device is attached to the tip of the undulating arm, and the base is pivotally supported on the base so as to be able to undulate. The link member has a distal end pivotally supported by the slide member and a base end pivotally supported by the base so as to be able to move up and down. The assisting force applying means includes an assisting force for raising the undulating arm against a load acting in a direction in which the undulating arm is tilted, the distal end portion being pivotally supported by the slide member and the base end portion being pivotally supported by the base. Is given. That is, the expansion and contraction operation is performed by the undulation of the link member, and a reaction force is generated by the expansion and contraction according to the undulation.

[0010] According to the work arm balance device thus constructed, a triangular link is formed by the base, the link member, and the auxiliary force applying means. Then, the slide member where the apex of the triangular link is located slides with respect to the undulating arm. Therefore, when the raising / lowering arm performs the raising / lowering operation with respect to the base, the position of the slide member with respect to the raising / lowering arm changes, and the application position of the auxiliary force by the auxiliary force applying means in the raising / lowering arm changes.

Here, when the assisting force applying means is arranged to push up the arm from below, when the assisting force applying means is compressed, the assisting force for raising the arm is increased, and the assisting force is increased. When the force applying means is extended, the assisting force decreases. When the slide member is located on the tip side of the undulating arm (the distance from the fulcrum of undulation to the position where the auxiliary force is applied is long), the auxiliary force for raising the undulating arm by the auxiliary force applying means is small. Good,
When the slide member is located on the base end side (the distance from the fulcrum of undulation to the position where the auxiliary force is applied is short), a large force is required to raise the undulating arm by the auxiliary force applying means. Even if the repulsive force changes in accordance with the expansion / contraction operation of the auxiliary force applying means, it is possible to suppress a change in the force for raising and lowering the undulating arm.

It is preferable that the work arm balance device be configured to adjust the assist force by changing the distance between the pivot portion of the assist force applying means and the pivot portion of the link member. With such a configuration, when the distance between the pivot portion of the assisting force applying means and the pivot portion of the link member is reduced, the angle formed between the assisting force applying means and the link member becomes small, so that the angle acts on the up-and-down arm. The reaction force of the assisting force applying means is reduced, and as a result, the assisting force acting in the direction in which the raising and lowering arms are raised can be reduced. Conversely, if the distance between the pivot portion of the assisting force applying means and the pivot portion of the link member is increased, the angle between the assisting force applying means and the link member increases, so that the auxiliary force acting in the direction of raising the raising / lowering arm is increased. Power can be increased.

In the above-mentioned work arm balance device, it is preferable to provide an up-and-down restricting means for restricting the operation of the slide member with respect to the up-and-down arm to restrict the up-and-down operation of the up-and-down arm. With such a configuration, the undulating arm can be easily held at a desired undulating angle.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. First, a working arm provided with a balance device according to the present invention will be described with reference to FIG. This work arm 1 is
It is attached to 0. The work table 90 includes a work table main body 91 formed in a box shape with a bottom, and a liner 92 disposed so as to cover the inside of the work table main body 91, and is configured such that an operator can board.

The work table 90 is provided on an aerial work vehicle (not shown). This aerial work vehicle has a swivel base that can be swiveled on a vehicle body, and a boom that can freely move up and down and expand and contract is mounted on the swivel base. A work table 90 is attached to the end of the boom so as to be able to swing horizontally in a horizontal direction while always maintaining a horizontal state irrespective of the elevation angle of the boom. Thereby, the worker who boarded the work table 90 can move to an arbitrary height through each operation of the swivel table and the boom.

The work arm 90 is attached to the work table 90. The work arm 1 includes a mounting device 10 that is configured to be detachable from a work table 90, and the mounting device 1.
0, a horizontal arm 20 extending in the horizontal direction so as to be horizontally pivotable, and an up-and-down balancer (work arm balance device) 30 which is horizontally rotatable with respect to this horizontal arm 20 and is arranged so as to be able to move up and down. And is configured.
The undulation balancer 30 is configured to be undulated at the same angle (for example, 40 °) from the horizontal state.

An undulating arm 60 is provided at the tip of the undulating balancer 30. In FIG.
Since 0 represents a state extending in the front-back direction of the figure,
Although the up / down operation direction and the like are not clearly shown, the up / down arm 60 is configured to freely move horizontally and up / down with respect to the up / down balancer 30. A hot stick holder 70 is provided at the tip of the undulating arm 60, and a hot stick (working device) H is held in the hot stick holder 70.

The mounting device 10 includes a main body 11 disposed inside the work table 90 and supporting the horizontal arm 20, and the main body 11 extends over the upper part of the side plate of the work table 90 from the work table 9.
A gripping arm 12 extending outside the main body 11 and gripping the side plate of the worktable 90 between itself and the main body 11, a detachable mechanism 14 for gripping / opening the gripping arm 12 with respect to the main body 11 by operating the lever 13. It is composed of

The mounting device 10 thus configured is firmly fixed to the upper side of the work table 90. Workbench 90
A base end portion 21 of a horizontal arm 20 is pivotally supported by the mounting device 10 fixed to the base member so that the base end portion 22 of the horizontal arm 20 can pivot freely.
1 is pivotally supported so as to be horizontally swingable.

Hereinafter, the undulating balancer 30 will be described with reference to FIGS. 1, 3 and 4. FIG. An upper arm 33 and a lower arm 34 are pivotally supported on the proximal member 31 by pivot pins 32a and 32b. A distal end member 35 is pivotally supported by distal end side pivot pins 36a, 36b at the distal ends of the arms 33, 34.
That is, a so-called parallel link is formed by the base member 31, the arms 33 and 34, and the tip member 35, and the tip member 3 is independent of the undulation angle of the arms 33 and 34.
5 is always kept vertical. The lower arm 34 is formed in a hollow square pipe shape so as to cover the outer periphery of the upper arm 33 and a gas spring (auxiliary force applying means) 38 described in detail later.

The parallel link constructed as described above is held by a triangular link which is also pivotally supported by the base member 31. The triangular link includes a base member 31, an upper link member 37, and a gas spring 38 serving as a lower link member.
It is composed of The base end of the upper link member 37 is pivotally supported by the elevating member 42 by a base-side pivot pin 32c. Since the elevating member 42 is attached to the base member 31 as described later in detail, the upper link member 37 is pivotally supported on the base member 31 so as to be able to move up and down.
The tip of the upper link member 37 is a roller support shaft 36.
By c, it is pivotally supported by two rollers 39,39.

The gas spring 38 has a bottom end 38b of a tube 38a and a tip end of an upper link member 37, which are pivotally supported by a roller 39 by a roller support shaft 36c. The end 38d of the rod 38c is moved by the proximal pivot pin 32d to a position near the proximal pivot pin 32b in the direction in which the lower arm 34 extends.
4 is pivoted. The end 38d of the rod 38c
May be pivotally supported by the base end member 31.

The roller 39 is held in long holes 34a, 34a formed on the left and right side surfaces of the lower arm 34 with an inner diameter slightly larger than the outer diameter of the roller 39. This long hole 34a
The roller 39 is formed to extend in the same direction (the front-rear direction) as the direction in which the lower arm 34 extends, and the roller 39 is rotatable in the elongated hole 34a (movable in the front-rear direction with respect to the lower arm 34). It is configured. The rollers 39 constitute a slide member described in the claims.

With such a configuration, the arms 33 and 34 in the horizontal state as shown in FIG.
When the roller 39 is raised, the roller 39 moves in the elongated hole 34a in the distal direction to extend the gas spring 38. Conversely, when the arms 33 and 34 are folded down, the roller 39 is elongated.
The gas spring 38 moves in the proximal direction in 4a and contracts.

The gas spring 38 generates a reaction force by being compressed. Since the bottom end 38b is locked to the lower arm 34 via the roller 39, the reaction force of the gas spring 38 causes the parallel link to resist the load acting in the direction in which the parallel link falls down. It will act as an auxiliary force to raise. Thus, the raising and lowering operation of the tip member 35 can be performed with a small force.

Here, in the gas spring 38,
When it is reduced (when the arm is folded down), its reaction force is large, and as it is extended (the arm is raised), the reaction force becomes smaller. For this reason, in the balance device according to the present invention, even if the reaction force changes due to the expansion and contraction of the gas spring 38, the force required to raise and lower the tip member 35 is not changed much.

The holding force of the gas spring 38 in the upright direction of the arm 34 will be described below with reference to FIG.
FIG. 6 is a schematic diagram of the undulating balancer 30. For convenience, the same reference numerals as those of the undulating balancer 30 will be used. As described above, the gas spring 38 contracts when the arm 34 falls down, and extends when the arm 34 is raised. That is, when the arm 34 falls down, the proximal-side pivot pin 32b
The distance K1 from the roller support shaft 36c to the arm 34
Is shorter than the distance K2 from the base-side pivot pin 32b to the roller support shaft 36c at the time of raising.

Here, if the moment M in the direction in which the arm 34 falls down is constant, the shorter the distance K,
4 requires a large assisting force (reaction force of the gas spring 38). In the above-described undulation balancer 30, the amount of increase in the auxiliary force required as the arm 34 is lowered and the amount of increase in the reaction force as the gas spring 38 is reduced are set to be substantially equal. . As a result, the force required for raising and lowering the arm 34 (elevating the tip member 35) is kept substantially constant.

In the undulating balancer 30, the upper link member holding device 40 pivotally supports the proximal-side pivot pin 32c to thereby provide a distance L between the proximal-side pivot pin 32c and the proximal-side pivot pin 32d. Can be changed. The upper link member holding device 40 includes a base 41 attached to the base end member 31, an elevating member 42 configured to be able to move up and down with respect to the base 41, and an elevating member for performing an elevating operation of the elevating member 42 with respect to the base 41. Screw 43
And a knob 44 for rotating the lifting screw 43.

The base 41 is formed in an inverted L-shape from a lifting member supporting portion 41a and a screw holding portion 41b.
The inner side surface 41c of the elevating member support portion 41a is formed in a so-called "groove" shape, and is configured to be able to move up and down without the elevating member 42 coming off. A rod-side end 38d is pivotally supported by the elevating member 42 by a proximal-side pivot pin 32c.

By rotating the knob 44, the upper link member holding device 40 having the above-described structure moves the proximal pivot pin 32c between the upper position shown by the solid line and the lower position shown by the chain line in FIG. Can be raised and lowered between Thus, the auxiliary force by the gas spring 38 can be adjusted by changing the distance L between the two base end pivot pins 32c and 32d.

The change in the assisting force by the gas spring 38 when the distance L is changed in this manner will be described with reference to FIGS. Here, assuming that the reaction force of the gas spring 38 is R and the angle θ1 between the upper link member 37 and the gas spring 38 is,
The force P capable of holding the upper link member 37 against the moment M acting in the direction in which the upper link member 37 falls (a force in a direction extending perpendicularly to the upper link member 37, hereinafter referred to as an "assisting force") is Equation 1

P = R · sin θ1 Equation 1

Accordingly, the two pivot pins 32c and 32d on the proximal side are provided.
When the distance L of the gas spring 38 is the same as that shown in FIG. 8 (by moving the proximal pivot pin 32c downward) as shown in FIG. And the gas spring 38 make an angle θ1 ′ smaller, so that the auxiliary force P ′ also becomes smaller. In other words, when the weight of the working device such as the hot stick H, which will be described in detail later, is light, the auxiliary force P is reduced by rotating the knob 44 and moving the proximal pivot pin 32c downward. Just do it. Conversely, when the weight of the working device 50 is heavy, the base end side pivot pin 32c may be moved upward to increase θ1 and increase the assisting force P.

The up-down balancer 30 is provided with a brake device (up-down control means) 50 so as not to perform up-down operation even when an external force is applied during operation. The brake device 50 includes a brake plate 51 fixed to the side surface of the lower arm 34, a brake holding member 52 disposed on the outer periphery of the roller support shaft 36c, and a brake plate 51 held by the brake holding member 52. An inner brake pad 53 located between the lower arm 34 and the brake holding member 5
2, an outer brake pad 54 positioned outside the brake plate 51, a push plate 55 disposed outside the outer brake pad 54, and a male screw 52 b formed on the outer periphery of the brake holding member 52. Handle 56 to be screwed
It is composed of

The brake plate 51 has an elongated hole 51a having the same length as the elongated hole 34a. A brake holding member 52 is inserted into the elongated hole 51a, but the brake holding member 52 is chamfered with a width slightly smaller than the width of the elongated hole 51a. The holding member 52 does not rotate. The lower arm 34 of the roller support shaft 36c is inserted into a through hole 52a formed through the brake holding member 52.
The part protruding from is inserted.

In the brake device 50 configured as described above, when the handle 56 is moved in the direction of the brake plate 51 by rotating the handle 56, the direction in which the brake pads 53 and 54 are pressed against the brake plate 51. Go to That is, by tightening the handle 56, the brake plate 51 is moved to the brake pads 53, 54.
The brake holding member 5
2 is fixed to the brake plate 51.

Since the roller support shaft 36c is inserted into the brake holding member 52 as described above, the roller support shaft 36c is
It is held without moving inside. Therefore, since the upper link member 37 and the gas spring 38 do not perform the undulating operation, and the triangular link is fixed,
The undulation balancer 30 is held at the undulation angle at which the brake is applied by the brake device 50.

The structure of the brake device is not limited to the above structure, and it is sufficient to prevent the movement of the roller 39 with respect to the lower arm 34.
Various configurations are possible. For example, the roller 39 may be fixed using a lock pin or the like.

Further, the configuration of the entire undulation balancer 30 is not limited to the above configuration. For example, depending on the spring constant of the gas spring 38, when the roller 39 moves not in a straight line but in an arc shape, the assisting force at the time of the undulating operation may be constant. In such a case, as shown in FIG. The slot 13 in which the roller 139 moves
4a may be formed in an arc shape.

As shown in FIG. 10, the upper link member 237 and the gas spring 23 with respect to the arm 234 are provided.
The movement of 8 does not necessarily need to be performed by the roller and the long hole as described above, and may be configured to be performed by the slider 239 configured to be capable of linear movement.
Further, a pivot pin for pivotally supporting the distal end of the upper link member 237 and a bottom end 238b of the gas spring 238 are provided.
It is not always necessary to integrate the pivot pins with the pivot pins for pivoting, and separate pivot pins 236a and 236b may be used.

An up-and-down arm 60 is provided at the end member 35 of the up-and-down balancer 30 having the above-described configuration so that the up-and-down balancer 30 can freely turn horizontally and up and down. Since the undulating arm 60 is known in various configurations, a detailed description thereof will be omitted.

A hot stick holder 70 is provided at the tip of the up / down arm 60 so as to be freely pivotable with respect to the up / down arm 60. The hot stick holder 70 shown in FIGS. 11 and 12 includes a column 71 supported at the tip of the up-and-down arm 60 so as to be horizontally pivotable, a lower support member 72 fixed to the upper end of the column 71, The upper support member 73 disposed on the support member 72, and the upper support member 73 attached to the lower support member 72 and the upper support member 73 so that the upper support member 73 can swing with respect to the lower support member 72 (openable and closable). ) And a hinge 74 to be held.

A lever holding plate 75 is fixed to the lower support member 72 so as to extend in the horizontal direction, and a receiving plate 76 is fixed to the upper support member 73. The lever holding plate 75 includes
An opening / closing lever 78 is provided via a lock plunger receiving plate 77. A lock plunger 79 is attached to the opening / closing lever 78. The contact portion 78a of the opening / closing lever 78 with the receiving plate 76 is formed in a tapered shape tapering outward. Then, when the open / close lever 78 is rotated from the open position shown by the chain line to the lock position shown by the solid line in FIG. 12, the locking portion 7 of the receiving plate 76 moves from the distal end portion 78b to the base end portion 78c in the contact portion 78a.
6a.

When the opening / closing lever 78 is rotated in this manner, the outer side of the abutting portion 78a (the side where the taper is narrowed) abuts on the locking portion 76a at the distal end portion 78b, and at the base end portion 78c. The inside of the contact portion 78a (the side where the taper is thicker) contacts the locking portion 76a. Accordingly, as the opening / closing lever 78 is rotated, the receiving plate 76 moves in the direction indicated by the arrow S (downward), so that the upper support member 73 approaches the lower support member 72 side.

The hot stick holder 70 thus configured has a sleeve 80 shown in FIGS.
, A hot stick H, which is a kind of a working device, is held. The sleeve 80 includes a first member 81 and a second member 82 formed of a metal material such as iron. The sleeve 80 has a cylindrical shape having an inner diameter slightly larger than the outer diameter of the hot stick H by combining the two members. The outer diameter of the sleeve 80 is substantially equal to the inner diameter of the hot stick holder 70 when the upper member 72 and the lower member 73 are combined (the open / close lever 78 is rotated to the open position).

Then, after the protective member 83 is wound around the outer periphery of the hot stick H so that the hot stick H is not damaged, the first member 8 is sandwiched by the protective member 83.
The first member and the second member 82 are combined, and both members 81 and 82 are firmly attached to the hot stick H with the fixing screws 84. The hot stick H to which the sleeve 80 is attached in this manner is attached to the hot stick holder 70 via the sleeve 80.

When attaching the hot stick H to the hot stick holder 70, first, FIG.
2, the upper support member 73 is rotated upward with the opening / closing lever 78 being rotated to the open position. Then, after placing the sleeve 80 on the lower support member 72, the upper support member 73 is rotated so as to cover the sleeve 80, and the opening / closing lever 78 is rotated to the lock position, so that the upper and lower support members 72, At 73, the sleeve 80 is securely held.

A lock plunger 79 is attached to the opening / closing lever 78, and a first plunger holding hole 77a and a second plunger holding hole into which the tip 79a of the lock plunger 79 is inserted are inserted into the plunger receiving plate 77. 77b is formed. First plunger holding hole 7
7a is an opening / closing lever 7 as shown by a solid line in FIG.
The second plunger holding hole 77b is capable of receiving the tip 79a of the lock plunger 79 when the open / close lever 78 is at the half-lock position when the lock lever 8 is at the lock position. It is formed in a suitable position.

Thus, when the opening / closing lever 78 is turned, the turning operation of the opening / closing lever 78 is temporarily restricted at the half-lock position and the locked position. The half-lock position of the opening / closing lever 78 is a state in which the contact portion 78a and the locking portion 76a are locked, but the upper support member 73 is completely pressed against the lower support member 72 side. This is a state in which the sleeve 80 does not come off, but the sleeve 80 can rotate with respect to the hot stick holder 70.

When the open / close lever 78 at the lock position and the half lock position is rotated, the lock plunger 79 is pulled in the direction indicated by the arrow T (downward).
The engagement between the first or second plunger holding holes 77a and 77b and the tip portion 79a of the lock plunger 79 is released.

According to the hot stick holder 70 thus configured, the hot stick H can be firmly held via the sleeve 80 by rotating the opening / closing lever 78 to the lock position. Then, when it is necessary to rotate the hot stick H while performing the operation using the hot stick H, it is only necessary to rotate the opening / closing lever 78 to the half lock position, and it is necessary to remove the hot stick H. There is no.

It should be noted that the sleeve is not limited to the above configuration, but may be configured as shown in FIG. The sleeve 180 includes a first member 181 and a second member 182 formed of a metal material similarly to the sleeve 80 described above. , 1
82 is fixed.

Furthermore, the hot stick holder is not limited to the above-described configuration, but may be configured as shown in FIG. This hot stick holder 17
Numeral 0 denotes a column 171 supported at the tip of the up-and-down arm 60 so as to be freely rotatable horizontally, a lower support member 172 fixed to the upper end of the column 171, and a support member 172 disposed on the lower support member 172. Upper support member 173 and lower support member 172
Lock 174,1 for fixing the upper support member 173 and the
74.

Lower support member 172 and upper support member 1
73 has a U-shaped cross section, and a lower fastening member 175 is attached inside the lower support member 172. A female screw is formed on the upper surface of the upper support member 173, and an elevating screw 176 is screwed to the female screw. A fastening member holding member 17 is provided at the lower end of the lifting screw 176.
The upper fastening member 178 is fixed to the fastening member holding member 178. In addition, lifting screw 1
A tightening force adjusting knob 179 is attached to the upper end of 76.

According to the hot stick holder 170 configured as described above, the locking of the snap locks 174 and 174 is released, and the sleeve 80 and the like attached to the hot stick H are provided between the fastening members 175 and 178. After being positioned, the snap locks 174 and 174 are locked. Then, by rotating the tightening force adjusting knob 179, the holding force of the sleeve 80 and the like (holding force by the hot stick holder 170) by the two tightening members 175 and 178 is adjusted.

That is, the hot stick holder 170
When firmly holding the hot stick H, the tightening force adjustment knob 179 is fully tightened. When fine adjustment of the rotation direction of the hot stick H is desired, the tightening force adjustment knob 179 may be slightly loosened to bring the same state as the half-lock state.

When the hot stick H is held by the hot stick holder 70 or the like, the sleeve 80
Are not always necessary. That is, if the configuration is such that the hot stick H is not damaged, the sleeve 80 and the like are unnecessary, and the hot stick holder 70 is half-locked, so that not only the rotation of the hot stick H but also the direction in which the hot stick H extends. (Movement in the front-back direction) is also possible.

In the above embodiment, the case where the hot stick H is used as the working device has been described. However, as the working device, a crimping machine for connecting electric wires and a device for attaching and detaching bolts are used. There are also torque wrenches, cable cutters, peeling tools, etc., which are replaced according to the work content. Here, since the weight of the working device varies depending on its type, when the working device is replaced or when a hot stick having a different length is used, the lifting screw 43 is rotated to rotate the proximal-side pivot pin 32c and the proximal-side pivot pin 32c. The auxiliary force of the undulating balancer 30 is adjusted by changing the distance L from the pivot pin 32d. Accordingly, the undulating operation of the undulating balancer 30 is performed in a state where the weight is balanced by the gas spring 38. Therefore, when the undulating operation is performed manually, the operator does not require a large amount of labor, and is performed by a cylinder or the like. Even in this case, the thrust of the cylinder can be reduced.

In the working arm 1 described above,
Although the gas spring 38 is used to apply the holding force in the undulating balancer 30, the present invention is not limited to this, and the holding force may be applied using a compression spring. Each of these springs does not necessarily need to be used for compression, but may be used for tension.

Further, in the working arm 1, the distance L between the proximal-side pivot pin 32c and the proximal-side pivot pin 32d of the up-and-down balancer 30 is adjustable, but the present invention is not limited to this. The configuration is not limited to this, and the positions of both pivot pins 32c and 32d may be fixed. Further, a shaft 32e connecting both pins 32a and 45 is provided.
Need not necessarily be inclined.

[0062]

As described above, the work arm balance device of the present invention is large in raising and lowering the raising and lowering arm when the auxiliary force by the auxiliary force applying means is increased by the raising and lowering of the raising and lowering arm. When a force is required and the assisting force provided by the assisting force applying means is reduced, the force required to raise the raising / lowering arm is reduced. Therefore, the force required to raise and lower the undulating arm can be made substantially uniform regardless of the change in the undulating angle of the undulating arm.

In the above-mentioned work arm balance device, the auxiliary force can be reduced by changing the distance between the pivot of the auxiliary force applying means for applying the auxiliary force for raising the raising and lowering arm and the pivot of the link member. Adjustments can be made. When the distance between the pivot portion of the auxiliary force applying means and the pivot portion of the link member is reduced, the auxiliary force can be reduced, and when the distance is increased, the auxiliary force can be increased. For this reason, if the distance is adjusted according to the weight of the working device, it is possible to always bring the up-and-down operation force of the arm into an appropriate state.

Further, in the work arm balance device according to the present invention, it is preferable to provide an up-and-down restricting means for restricting the operation of the slide member with respect to the up-and-down arm to restrict the up-and-down operation of the up-and-down arm. With such a configuration, the undulating arm can be easily held at a desired undulating angle with a simple configuration.

[Brief description of the drawings]

1 is a sectional view showing a balance device for a working arm according to the present invention, and is a sectional view taken along the line II in FIG. 3;

FIG. 2 is a side view of a working arm provided with the balance device.

FIG. 3 is a side view showing an operation state of the balance device.

FIG. 4 is a sectional view of the balance device taken along line IV-IV in FIG. 1;

FIG. 5 is a sectional view of the balance device taken along line VV in FIG. 4;

FIG. 6 is a schematic view showing the balance device.

FIG. 7 is a schematic view showing the balance device.

FIG. 8 is a schematic view showing the balance device.

FIG. 9 is a side view showing a work arm balance device having a different configuration according to the present invention.

FIG. 10 is a side view showing a work arm balance device having a different configuration according to the present invention.

FIG. 11 is a front view of a hot stick holder used for the working arm.

FIG. 12 is a cross-sectional view of the hot stick holder taken along the line XII-XII in FIG. 11;

13A is a side view of a sleeve used for the hot stick holder, and FIG.
The cross section is shown in (B).

FIG. 14 is a side view of another sleeve used in the hot stick holder, and FIG.
The -D section is shown in (D).

FIG. 15 is a front view of a hot stick holder having a different configuration used for the working arm.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Working arm 10 Mounting device 20 Horizontal arm 30 Unbalanced balancer (balanced device of work arm) 31 Base member (base) 34 Lower arm (undulated arm) 37 Upper link member (link member) 38 Gas spring (assisted) 39) Roller (slide member) 40 Upper link member holding device 50 Brake device (undulation regulating device) 60 Undulation arm 70 Hot stick holder 80 Sleeve H Hot stick (working device)

Claims (3)

[Claims] An operating arm is attached to a distal end of the arm, and a base end is pivotally supported on the base so as to be able to move up and down, and is provided on the arm so as to extend in the same direction as the axial direction of the arm. A slide member slidable; a link member having a distal end pivotally supported by the slide member and a base end pivotally supported by the base so as to be able to undulate; a distal end pivotally supported by the slide member; A work arm balancing device, wherein a base end portion is pivotally supported on the base end side of the base or the up-and-down arm, and auxiliary force applying means for applying an auxiliary force to raise the up-and-down arm. . 2. The adjustment of the assisting force by changing a distance between a pivoting portion between the assisting force applying means and the base and a pivoting portion between the link member and the base. 2. The work arm balance device according to claim 1. 3. An up-and-down restricting means for restricting the operation of the slide member with respect to the up-and-down arm, thereby restricting the up-and-down operation of the up-and-down arm.
Alternatively, the work arm balance device according to claim 2.