JP7230737B2 - construction machinery - Google Patents

Description

TECHNICAL FIELD The present invention relates to construction machines, and more particularly to construction machines having treads on the sides of an upper revolving structure.

2. Description of the Related Art Conventionally, there is known a large hydraulic excavator having a catwalk (footboard) on the side of an upper revolving structure (for example, Patent Document 1). Specifically, as shown in FIG. 1 of Patent Document 1, a catwalk (16) is installed along the side surface (6a) of the upper swing body (6). The catwalk (16) has a movable part (18) that rotates around an axis (Y) located on the side (6a) at the rear end of the upper swing body (6). When the bumper (26) of the movable part (18) comes into contact with the obstacle (S), the movable part (18) moves upward as indicated by an arrow (Z2) (see FIG. 3 of Patent Document 1) centering on the axis (Y). rotates (is flipped up).

JP 2015-21272 A

In Patent Document 1 described above, a configuration is adopted in which a reaction force from an obstacle such as earth and sand or rocks is used to push up a footboard, and it is assumed that the footboard collides with the obstacle. However, even if the footboard collides with an obstacle, there is no guarantee that the footboard will spring up, and there is a risk that the footboard will be damaged depending on the degree of collision.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a construction machine capable of operating a footboard provided on the side surface of an upper revolving body without contacting an obstacle.

In order to achieve the above object, the present invention provides a construction machine having an upper revolving body including an upper frame, a machine body mounted on the upper frame, and a counterweight provided at the rear of the machine body, A tread plate is attached to a side surface of the upper frame and is rotatable between a horizontal state and a vertical state lifted upward from the horizontal state about an axis located on the side of the upper frame. A cutout region is formed in the front side end to be concave to the rear, and a drive mechanism for rotating the footboard is arranged in the cutout region, and the longitudinal direction of the drive mechanism is vertical. A drive link including a direct-acting actuator arranged to match the direction, and one end and the other end with a rotation shaft interposed therebetween, the one end being rotatable with respect to the lower end of the actuator and a driving link connected to the treadplate so that the other end is rotatably connected to the treadplate. rotates from the horizontal state to the vertical state, and when the lower end portion of the actuator contracts, the drive link rotates in a direction opposite to the predetermined direction, and the footboard moves from the vertical state to the horizontal state. To provide a construction machine characterized by rotating toward.

Here, the actuator is a direct-acting hydraulic actuator, and it is preferable that the rod of the hydraulic actuator is arranged on the upper side and the cylinder tube is arranged on the lower side.

In addition, the drive mechanism further includes a support member that rotatably supports the drive link, the support member is fixed to the counterweight in the notch region, and is fixed to the counterweight in the notch region of the support member. It is preferable that the rotation shaft of the drive link is provided in a portion projecting from the area to the side of the machine.

According to the present invention, a notch region that is recessed rearward is formed at the front side end of the counterweight, and the footboard provided on the side surface of the upper swing body is turned from the horizontal state to the vertical state or from the vertical state to the horizontal state. A drive mechanism for rotating is arranged in the notch area. Therefore, it is possible to reliably operate the footboard without contacting an obstacle, thereby preventing damage to the footboard.

1 is a side view showing a hydraulic excavator (construction machine) according to an embodiment of the present invention; FIG. II arrow view of FIG. 1 (plan view of the hydraulic excavator). The figure which looked at the front right edge (notch area|region) of counterweight from the machine front side. IV arrow directional view of FIG. FIG. 3 is a cross-sectional view taken along the line VV in FIG. 2; FIG. 6 is a cross-sectional view taken along line VI-VI of FIG. 5; Schematic diagram showing a tread in a horizontal state. Schematic diagram showing a tread in a vertical state. The figure which shows the state which the lower end part of the hydraulic actuator extended from the state of FIG.

<1. embodiment>
A construction machine according to an embodiment of the present invention will be described with reference to FIGS. 1 to 9. FIG. Below, the hydraulic excavator 1 shown in FIG. 1 is illustrated as an example of a construction machine.

As shown in FIG. 1 , the hydraulic excavator 1 includes a crawler-type lower running body 2 and an upper revolving body 3 mounted on the lower running body 2 so as to be capable of turning.

The upper revolving structure 3 includes an upper frame 30, a cab (cab) 31 mounted on the upper frame 30, a machine body 33 also mounted on the upper frame 30, and a counterweight 4 provided at the rear of the machine body 33. and

As shown in FIGS. 1 and 2, on the left and right side surfaces of the upper frame 30, footboards 5L and 5R (also called catwalks) are installed as passages for inspection work.

The footboard 5L has three footboards 51, 53, and 55 arranged side by side from the front to the rear. The two front treads 51 and 53 are configured as fixed treads and are always fixed in a horizontal state (used state). On the other hand, the rearmost footboard 55 is configured as a movable footboard, and is switched between a horizontal state (footboard use state) and a vertical state (footboard retracted state) using a drive mechanism 6 (see FIG. 5), which will be described later. configured as possible.

The footboard 5R has three footboards 52, 54, and 56 arranged from the front to the rear. The two front treads 52 and 54 are configured as fixed treads and are always fixed in a horizontal state (used state). On the other hand, the rearmost footboard 56 is configured as a movable footboard, and can be switched between a horizontal state (footboard use state) and a vertical state (footboard retracted state) by a drive mechanism 6 (see FIG. 5), which will be described later. It is configured.

As shown in FIG. 2, cutout areas 40 are formed at the left and right ends of the counterweight front surface 41 so as to be recessed toward the rear of the machine. Note that the notch region 40 and the drive mechanism 6 (see FIG. 5) arranged therein are configured symmetrically. Therefore, the right side of the machine will be described below, and the description of the left side of the machine will be omitted.

In FIGS. 3 and 4, the cutout area 40 is shown without the drive mechanism 6 attached. As shown in FIGS. 3 and 4, a bracket 42 is welded to the front side of the cutout region 40 . A pin 43 is welded to the front surface of the bracket 42 for rotatably connecting the upper end (the rod tip) of the hydraulic actuator 63 .

Two vertically arranged bosses 44 with female threads are welded to the front side of the notch region 40 . A drive link support member 61 (see FIG. 5), which will be described later, is attached to the female threaded boss 44 .

As shown in FIG. 5, the drive mechanism 6 for rotating the footboard 56 is arranged in the notch region 40 described above.

The drive mechanism 6 includes a drive link support member 61 , a drive link 62 , and a linear hydraulic actuator 63 .

The drive link support member 61 is a triangular plate member for rotatably supporting the drive link 62 . As shown in FIGS. 5 and 6 , the drive link support member 61 is attached to the counterweight 4 via a female threaded boss 44 provided at the lower front face of the cutout area 40 . Further, the drive link support member 61 has a rotation axis RA1 of the drive link 62 in a portion projecting from the notch area 40 to the right side of the machine.

The drive link 62 is rotatably attached to the rotation axis RA1 of the drive link support member 61, and has a dogleg shape extending to the machine center side and the machine right side with the rotation axis RA1 interposed therebetween. It is a member.

As shown in FIGS. 5 and 6 , the end of the drive link 62 on the machine center side is rotatably connected to the lower end (cylinder tube side end) of the hydraulic actuator 63 . The end of the drive link 62 on the right side of the machine is rotatably connected to the rear end side surface of the footboard 56 . A long hole 62H is formed in the end portion of the drive link 62 on the right side of the machine, and a pin PN1 provided on the rear end side surface of the tread plate 56 is rotatably inserted into the long hole 62H.

The hydraulic actuator 63 is a hydraulic cylinder for rotating the drive link 62, and is arranged so that its longitudinal direction (stretching direction) coincides with the vertical direction. Specifically, of the hydraulic actuator 63, the rod (rod distal end) is arranged on the upper side, and the cylinder tube (head proximal end) is arranged on the lower side. It should be noted that the hydraulic actuator 63 is arranged so as to always fit within the notch region 40 even when it is extended and retracted.

As shown in FIG. 5, the rod tip of the hydraulic actuator 63 is rotatably connected to the pin 43 described above. As shown in FIG. 6, the cylinder tube base end of the hydraulic actuator 63 is rotatably connected to the end of the drive link 62 on the machine center side.

Next, the configuration of the right footboard 56 and its surroundings will be described in detail with reference to FIGS. 7 and 8. FIG.

As shown in FIGS. 7 and 8 , the footboard 56 includes a footboard 560 , a hinge 563 located on the right side surface of the upper frame 30 , and a downward stopper 565 .

The tread surface 560 is a horizontal surface that faces upward when the tread plate 56 is lowered (the state shown in FIG. 7), and functions as a passage for inspection work.

The hinge 563 is a rotating shaft that rotates around an axis located on the right side surface of the upper frame 30 . The tread plate 56 can rotate between a horizontal state (state shown in FIG. 7) and a vertical state (state shown in FIG. 8) with a hinge 563 as a rotational axis.

The lowering stopper 565 is a rubber-like member that contacts the right side surface of the upper frame 30 when the tread plate 56 is in the horizontal state (the state shown in FIG. 7). A rubber-like lifting stopper 331 (see FIGS. 7 and 8) is provided on the right side surface of the machine body 33, and when the tread plate 56 is in a vertical state (the state shown in FIG. 8), the tread plate 56 is pressed against the lifting stopper 331. tread surface 560 abuts.

Next, referring to FIGS. 5 and 9, the switching operation of switching the footboard 56 between the horizontal state (FIG. 5) and the vertical state (FIG. 9) via the drive mechanism 6 will be described.

In this embodiment, the tread plate 56 is configured to be in a horizontal state (the state shown in FIG. 5) when the hydraulic actuator 63 is most contracted.

As shown in FIG. 9, when the hydraulic actuator 63 is operated to extend the lower end of the hydraulic actuator 63 (the end on the cylinder tube side), the driving link 62 rotates counterclockwise ( counterclockwise). When the drive link 62 rotates counterclockwise, the tread plate 56 connected to the machine right end of the drive link 62 rotates from the horizontal state (FIG. 5) to the vertical state (FIG. 9).

On the other hand, when the tread plate 56 is in the vertical state (state shown in FIG. 9), the hydraulic actuator 63 is actuated to contract the lower end of the hydraulic actuator 63 (the end on the cylinder tube side). , the drive link 62 rotates rightward (clockwise) when viewed from the front. When the drive link 62 rotates clockwise, the tread plate 56 connected to the machine right end of the drive link 62 rotates from the vertical position (FIG. 9) to the horizontal position (FIG. 5).

Although the description is omitted, the left footboard 55 also has the same structure as the footboard 56 described above, and can be switched between the horizontal state and the vertical state.

According to the above-described embodiment, the notch regions 40 are formed at the left and right side ends of the front counterweight front surface 41 so that the treads 55 and 56 provided on the left and right side surfaces of the upper frame 30 can be moved from the horizontal state to the vertical state. Alternatively, the driving mechanism 6 for rotating from the vertical state to the horizontal state is arranged in the notch region 40 . Therefore, during normal operation (during work), the driving mechanism 6 is used to rotate the treads 55 and 56 to a vertical state, thereby avoiding contact of the treads 55 and 56 with obstacles such as sand and rocks. It is possible. That is, it is possible to reliably operate the footboards 55 and 56 without coming into contact with obstacles, thereby preventing damage to the footboards.

In particular, in this embodiment, since the drive mechanism 6 is arranged in the notch area 40, it is possible to avoid damage to the hydraulic actuator 63 and its piping due to collision with an object during work.

In the above-described embodiment, the hydraulic actuator 63 is arranged above the drive link 62, and the tread plate 56 rotates vertically as the hydraulic actuator 63 extends. Therefore, even if the hydraulic actuator 63 leaks oil and the hydraulic actuator 63 unintentionally expands, the tread plate 56 rotates to a vertical state, that is, to the side to avoid contact with an obstacle, so that a free fall occurs. and rattling can be suppressed.

In the above-described embodiment, of the hydraulic actuator 63, the rod is arranged on the upper side and the cylinder tube is arranged on the lower side. It is possible to apply the load of the cylinder tube (body side).

Further, according to the above-described embodiment, since the female threaded boss 44 is provided in the notch region 40 , collision of the female threaded boss 44 with an object during operation can be avoided, and the drive link support member 61 can be attached to the counterweight 4 . It is possible to fix it more reliably.

<2. Variation>
The construction machine according to the present invention is not limited to the above-described embodiments, and various modifications and improvements are possible within the scope of the claims.

For example, in the above-described embodiment, the rod is arranged on the upper side of the hydraulic actuator 63, and the cylinder tube is arranged on the lower side. may be arranged on the lower side.

Further, in the above-described embodiment, the case where the hydraulic actuator 63 is used as the linear actuator is illustrated, but the present invention is not limited to this, and the linear actuator may use an electric actuator.

Further, in the above-described embodiment, only the rearmost footboards 55 and 56 of the left and right footboards 5L and 5R are rotatable, but the present invention is not limited to this. For example, the left and right footboards 5L and 5R may be configured as one long footboard in the front-rear direction, and the entire left and right footboards 5L and 5R may be configured to be rotatable.

In the above-described embodiment, the footboards 5L and 5R are provided on the left and right sides of the upper frame 30 as an example. may In that case, the drive mechanism 6 may be arranged only in the notch area 40 on the side where the footboard is provided.

As described above, the construction machine according to the present invention is suitable for a hydraulic excavator or the like having footboards on the sides of the upper revolving structure.

1 hydraulic excavator, 2 lower running body, 3 upper revolving body, 4 counterweight,
5L, 5R treads, 6 drive mechanism, 30 upper frame, 33 machine body,
40 notch area, 41 counterweight front surface, 42 bracket,
43 pin, 44 boss, 51,53,55 footboard, 52,54,56 footboard,
61 drive link support member, 62 drive link, 62H long hole,
63 hydraulic actuator, 331 stopper, 560 tread, 563 hinge,
565 stopper, PN1 pin, RA1 rotation shaft

Claims (3)

A construction machine comprising an upper revolving body including an upper frame, a machine body mounted on the upper frame, and a counterweight provided at the rear of the machine body,
A tread plate is attached to a side surface of the upper frame and is rotatable between a horizontal state and a vertical state lifted upward from the horizontal state about an axis located on the side of the upper frame,
A notch area recessed rearward is formed at the front side end of the counterweight,
A drive mechanism for rotating the footboard is arranged in the notch area,
The drive mechanism is
a direct-acting actuator arranged such that its longitudinal direction coincides with the vertical direction;
A driving link including one end and the other end with a rotation shaft interposed therebetween, the one end being rotatably connected to the lower end of the actuator, and the other end being rotatable relative to the footboard a drive link operably coupled;
with
When the lower end of the actuator extends, the drive link rotates in a predetermined direction, and the footboard rotates from the horizontal state toward the vertical state,
The construction machine according to claim 1, wherein when the lower end of the actuator contracts, the drive link rotates in a direction opposite to the predetermined direction, and the tread plate rotates from the vertical state toward the horizontal state. The actuator is a direct-acting hydraulic actuator,
The construction machine according to claim 1, wherein the rod is arranged on the upper side and the cylinder tube is arranged on the lower side of the hydraulic actuator. The drive mechanism further includes a support member that rotatably supports the drive link,
the support member is secured to the counterweight at the cutout area;
3. The construction machine according to claim 1, wherein the rotation shaft of the drive link is provided in a portion of the support member that protrudes from the notch area toward the side of the machine.

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