JP7230733B2 - construction machinery - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a construction machine, and more particularly to a construction machine having a pair of left and right footboards on the left and right 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 cab (8). 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 the above-mentioned Patent Document 1, 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 tread, and it is assumed that the tread will collide with the obstacle. However, there is no guarantee that the footboard will bounce up as expected in response to collision with the obstacle, and there is a risk that the footboard itself will be damaged depending on the degree of collision with the obstacle.

In order to avoid damage to the treads, it is preferable to be able to operate the treads without contacting the treads with an obstacle. Further, when footboards are provided on the left and right sides of the upper revolving body, it is preferable that the left and right footboards can be operated simultaneously.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a construction machine capable of simultaneously operating left and right footboards provided on left and right side surfaces 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, Left and right footboards are provided on the left and right side surfaces of the upper frame, respectively, and are rotatable between a horizontal state and a vertical state lifted upward from the horizontal state about axes positioned on the left and right side surfaces. A drive mechanism is arranged in a gap between the rear end of the machine body and the front surface of the counterweight for simultaneously operating the left tread and the right tread, and the drive mechanism is centered around a rotation shaft. a driving device for rotating the driving link; a left connecting link connecting the driving link and the left tread; and a driving link and the right tread. a connecting right connecting link, the drive link including a first arm extending in a first direction from the pivot shaft and a second arm extending in a second direction from the pivot shaft; Of the links, the end on the center side of the machine is rotatably connected to the tip of the first arm, while the end on the left side of the machine is rotatably connected to the left tread plate. Of these, the end on the center side of the machine is rotatably connected to the distal end of the second arm, while the end on the right side of the machine is rotatably connected to the right footboard. is in the horizontal state, when the drive link rotates in a predetermined direction due to the drive of the drive device, the left connection link connected to the tip of the first arm moves to the right side of the machine and When the right connecting link connected to the distal end of the second arm moves to the left side of the machine, the left footboard and the right footboard rotate toward the vertical state, and the left footboard and the right footboard move toward the vertical position. In the vertical state, when the drive link rotates in a direction opposite to the predetermined direction as the drive device is driven, the left connection link connected to the tip of the first arm moves to the left side of the machine. A construction machine characterized in that the right connecting link that moves and is connected to the tip of the second arm moves to the right side of the machine, thereby rotating the left footboard and the right footboard toward the horizontal state. offers.

Here, the drive device is configured as a direct-acting hydraulic actuator, the drive link further includes a third arm extending in a third direction from the rotation shaft, and the third arm of the drive link is An end portion of the hydraulic actuator is rotatably connected to the distal end side, and the drive link is configured to rotate about the rotation shaft as the hydraulic actuator expands and contracts. preferable.

Further, the hydraulic actuator is arranged above the drive link so that its longitudinal direction is aligned with the vertical direction, and the lower end of the hydraulic actuator is rotatably connected to the tip of the third arm, and the The drive link rotates in the predetermined direction when the lower end of the hydraulic actuator expands, and rotates in a direction opposite to the predetermined direction when the lower end of the hydraulic actuator contracts. preferably configured.

Moreover, it is preferable that the rod is arranged on the upper side and the cylinder tube is arranged on the lower side among the hydraulic actuators.

Further, the left tread is provided with a left connecting member that extends upward from the tread in the horizontal state and is connectable to the machine left end of the left connecting link, and the right tread is provided with the left connecting member in the horizontal state. It is preferable that a right connecting member is provided that extends upward from the tread surface and is connectable to the end of the right connecting link on the right side of the machine.

According to the present invention, the drive mechanism for simultaneously actuating the left tread and the right tread is arranged in the gap between the rear end of the machine body and the front face of the counterweight. Therefore, the left and right footboards provided on the left and right side surfaces of the upper revolving body can be operated simultaneously without contacting an obstacle.

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). FIG. 3 is a cross-sectional view taken along line III-III in FIG. 2; FIG. 4 is a cross-sectional view taken along line IV-IV of FIG. 3; FIG. 4 is an enlarged view of the periphery of the left footboard shown in FIG. 3; VI Arrow directional view of FIG. The figure which shows the hydraulic actuator and drive link which are in the most retracted state. The figure which shows the hydraulic actuator and drive link extended from the most retracted state. FIG. 9 is a view showing the hydraulic actuator and drive link further extended from the state shown in FIG. 8; The figure which shows the footboard in a vertical state (storage state). The figure which shows the drive mechanism which concerns on a modification.

<1. embodiment>
A construction machine according to an embodiment of the present invention will be described with reference to FIGS. 1 to 10. 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. 3), 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. 3) described later. It is configured.

As shown in FIG. 2, a gap SP exists between the rear end 33E of the machine body 33 and the front surface 41 of the counterweight 4. As shown in FIG. The gap SP penetrates in the machine width direction (horizontal direction) above a pair of left and right vertical plates 32L and 33R (see FIG. 3) erected on the bottom plate of the upper frame 30. As shown in FIG. In the gap SP, as shown in FIGS. 3 and 4, a drive mechanism 6 is arranged for simultaneously operating the left and right footboards 55 and 56 described above. Specifically, the drive mechanism 6 is arranged substantially in the center of the front surface 41 of the counterweight 4 in the machine width direction (between the pair of left and right vertical plates 32L and 33R).

The drive mechanism 6 includes a drive link 61, a direct acting hydraulic actuator 63 arranged above the drive link 61, and a left connection link 65 and a right connection link 67 connected to the drive link 61. Configured.

The drive link 61 is configured to be rotatable about a rotation axis RA1 and has three arms 611, 612, 613 extending in three directions from the rotation axis RA1.

As shown in FIG. 4, the arm 611 is composed of two plate members facing each other in the front-rear direction and welded to the outer periphery of the rotation shaft RA1. As shown in FIGS. 3 and 4, the distal end of the arm 611 is rotatably connected to the lower end (the head-side end) of the hydraulic actuator 63 . Arm 611 is an example of a third arm according to the present invention.

As shown in FIG. 4, the arms 612 and 613 are made of a single plate member and are welded to the outer periphery of the rotation shaft RA1 like the arm 611. As shown in FIG. As shown in FIGS. 3 and 4, the arms 612 and 613 extend in opposite directions across the rotation axis RA1. The tip of the arm 612 is rotatably connected to the end of the left connecting link 65 on the machine center side. The tip of the arm 613 is rotatably connected to the end of the right connecting link 67 on the machine center side. The arm 612 is an example of the first arm according to the invention, and the arm 613 is an example of the second arm according to the invention.

Since the three arms 611 to 613 described above are all welded and fixed to the outer circumference of the rotation axis RA1, they can rotate about the rotation axis RA1 while maintaining the arrangement relationship shown in FIG. do.

The hydraulic actuator 63 is a hydraulic cylinder for rotating the drive link 61, and is an example of the drive device according to the present invention. The hydraulic actuator 63 is arranged above the drive link 61 such that its longitudinal direction (stretching direction) coincides with the vertical direction. Specifically, the rod of the hydraulic actuator 63 is arranged on the upper side, and the cylinder tube is arranged on the lower side.

As shown in FIG. 4, a rotation axis RA2 is provided on the upper portion of the front surface 41 of the counterweight 4, and the end portion of the hydraulic actuator 63 on the rod side (the upper end portion of the hydraulic actuator 63) is provided with respect to the rotation axis RA2. ) are rotatably connected. On the other hand, the end of the hydraulic actuator 63 on the cylinder tube side (the lower end of the hydraulic actuator 63) is rotatably connected to the tip of the arm 611 described above.

As shown in FIG. 3 , the left connection link 65 is arranged on the left side of the drive link 61 and connects the arm 612 and the footboard 55 . Specifically, the end of the left connection link 65 on the machine center side is rotatably connected to the tip of the arm 612 . The end of the left connection link 65 on the left side of the machine is rotatably connected to a connection bracket 551 provided on the tread surface of the tread plate 55 via a turnbuckle 71 and a bifurcated bolt 73 .

Similarly, the right connecting link 67 is arranged on the right side of the drive link 61 and connects the arm 613 and the footboard 56 (see FIG. 2). Since the rest of the configuration is bilaterally symmetrical to the left connecting link 65 described above, detailed description thereof will be omitted.

Next, the configuration of the left footboard 55 and its surroundings will be described in detail with reference to FIGS. 5 and 6. FIG. Note that the configuration of the right footboard 56 and its surroundings is bilaterally symmetrical to the configuration of the left footboard 55 and its surroundings, so the description thereof will be omitted below.

As shown in FIGS. 5 and 6, the tread 55 includes a tread 550, a plate-shaped connection bracket 551 extending upward from the tread 550, a hinge 553 positioned on the left side of the upper frame 30, a lower and a stopper 555 .

The tread surface 550 is a horizontal surface that faces upward when the tread plate 55 is lowered, and is a portion that functions as a passage for inspection work.

The connection bracket 551 is a plate member to which the mechanical left end of the left connection link 65 is connected via the turnbuckle 71 and the bifurcated bolt 73, and is an example of the left connection member according to the present invention.

An upper portion of the connection bracket 551 is formed with an insertion hole for a connecting pin that rotatably connects the bifurcated bolt 73 . The connecting pin is inserted through the insertion hole while the bifurcated bolt 73 clamps the upper portion of the connection bracket 551 , and the bifurcated bolt 73 is rotatably connected to the connection bracket 551 . A turnbuckle 71 is arranged between the machine left end of the left connecting link 65 and the bifurcated bolt 73 so that the length of the left connecting link 65 in the longitudinal direction can be finely adjusted.

The hinge 553 is a rotating shaft that rotates around an axis located on the left side of the upper frame 30 . The tread plate 55 can rotate between a horizontal state (state shown in FIG. 5) and a vertical state (state shown in FIG. 10) with a hinge 553 as a rotational axis.

The lowering stopper 555 is a rubber-like member that contacts the left side surface of the upper frame 30 when the tread plate 55 is in the horizontal state (see FIG. 5). A rubber-like raising stopper 331 (see FIG. 5) is provided on the left side surface of the machine body 33, and when the tread plate 55 is in a vertical state (see FIG. 10), the tread surface 550 of the tread plate 55 touches the raising stopper 331. abuts.

Next, a switching operation for switching the left and right footboards 55 and 56 between the horizontal state (FIG. 5) and the vertical state (FIG. 10) using the drive mechanism 6 will be described with reference to FIGS. 7 to 9. FIG.

In this embodiment, the tread plate 55 is configured to be in a horizontal state (state shown in FIG. 5) when the hydraulic actuator 63 is most contracted (state shown in FIG. 7, hereinafter simply referred to as the most contracted state). there is

As shown in FIG. 8, when the hydraulic actuator 63 is operated to extend the lower end of the hydraulic actuator 63 from the most contracted state, the drive link 61 rotates rightward (clockwise) in front view. When the drive link 61 rotates clockwise, the tip of the arm 612 and the left connecting link 65 move to the right side of the machine, and the tip of the arm 613 and the right connecting link 67 move to the left side of the machine. Since the machine left end of the left connecting link 65 and the machine right end of the right connecting link 67 are connected to the left and right footboards 55 and 56, respectively, the left and right footboards 55 and 56 that were in the horizontal state At the same time, it starts rotating toward the vertical state.

As shown in FIG. 9, when the lower end of the hydraulic actuator 63 further extends from the state shown in FIG. 8, the drive link 61 rotates further clockwise. Along with this, the tip of the arm 612 and the left connecting link 65 move further to the right side of the machine, the tip of the arm 613 and the right connecting link 67 move further to the left side of the machine, and the left and right footboards 55 and 56 move further upward. Lift to.

As described above, when the hydraulic actuator 63 extends and the drive link 61 rotates clockwise, the left and right treads 55 and 56 are finally vertical (the treads are facing the inside of the machine).

Further, as shown in FIG. 10, when the left and right footboards 55 and 56 are in a vertical state, the hydraulic actuator 63 is actuated and the lower end of the hydraulic actuator 63 is contracted. (counterclockwise). When the drive link 61 rotates counterclockwise, the tip of the arm 612 and the left connecting link 65 move to the left side of the machine, and the tip of the arm 613 and the right connecting link 67 move to the right side of the machine. Along with this, the left and right footboards 55 and 56 simultaneously rotate from the vertical state toward the horizontal state.

According to the above-described embodiment, the drive mechanism 6 for simultaneously operating the left and right footboards 55 and 56 is arranged in the gap between the rear end 33E of the machine body 33 and the front surface 41 of the counterweight 4. As shown in FIG. The drive mechanism 6 includes a drive link 61 , a hydraulic actuator 63 , a left connection link 65 and a right connection link 67 . The expansion and contraction motion of the hydraulic actuator 63 is transmitted to both the left connecting link 65 and the right connecting link 67 via the drive link 61, and the left and right footboards 55, 56 operate simultaneously.

Therefore, during normal operation, the left and right footboards 55 and 56 are rotated from the horizontal state to the vertical state by using the drive mechanism 6 to avoid contacting the left and right footboards 55 and 56 with obstacles such as sand and rocks. It is possible to In addition, since one hydraulic actuator 63 can be used to simultaneously drive the left and right footboards 55 and 56, a simple configuration can be realized, and costs can be reduced. Furthermore, since the hydraulic actuator 63 is arranged inside the fuselage, it is possible to avoid damage to the hydraulic actuator 63 and its pipes due to collision with an object during operation.

Further, according to the above-described embodiment, the drive link 61 is composed of three arms 611, 612, 613 extending in three directions from the rotation axis RA1. The tip of the arm 611 serves as the driving fulcrum of the hydraulic actuator 63 . Also, the tip of the arm 612 serves as a driving fulcrum for the left connecting link 65 , and the tip of the arm 613 serves as a driving fulcrum for the right connecting link 67 . That is, it is possible to configure the driving fulcrum of the hydraulic actuator 63, the driving fulcrum of the left connecting link 65, and the driving fulcrum of the right connecting link 67 in a rational integrated structure.

In the above-described embodiment, the hydraulic actuator 63 is arranged above the drive link 61, and the left and right footboards 55 and 56 rotate vertically as the hydraulic actuator 63 extends. Therefore, even if the hydraulic actuator 63 leaks oil and the hydraulic actuator 63 unintentionally expands, the left and right footboards 55 and 56 rotate to a vertical state, that is, to avoid contact with obstacles. Therefore, free fall 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) in the moving direction.

Further, according to the above-described embodiment, since the connection bracket 551 extends upward from the tread 550, the connection bracket 551 is arranged in the gap SP in the vertical state (the tread stored state) (FIG. 10). can avoid object collision in

<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 hydraulic actuator 63 is used to rotate the drive link 61. However, the present invention is not limited to this, and the stepping motor MT (see FIG. 11) is used to rotate the drive link 61. You can let it run.

Specifically, as shown in FIG. 11, the stepping motor MT may be arranged on the rotation axis RA1 of the drive link 61. As shown in FIG. According to this modification, the drive link 61 only needs to have arms 612 and 613 extending in two directions, and the arm 611 for connecting the lower end of the hydraulic actuator 63 as in the above-described embodiment is unnecessary. be.

Further, according to the above-described embodiment, only the rearmost stepboards 55, 56 of the left and right stepboards 5L, 5R are configured to be 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.

Further, according to the above-described embodiment, the case where the drive mechanism 6 is provided on the front surface 41 of the counterweight 4 has been exemplified, but the present invention is not limited to this. If the drive mechanism 6 is arranged in the gap SP, it may be provided on the upper frame 30 side.

As described above, the construction machine according to the present invention is suitable for a hydraulic excavator or the like having a pair of left and right footboards on the left and right 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, 32L, 33R vertical plate,
33 machine body, 51, 53, 55 treads, 52, 54, 56 treads,
61 drive link, 63 hydraulic actuator, 65 left connecting link,
67 right connecting link, 71 turnbuckle, 73 bifurcated bolt, 331 stopper,
550 tread, 551 connection bracket, 553 hinge, 555 stopper,
611, 612, 613 arm, MT stepping motor,
RA1 rotation axis, RA2 rotation axis, SP gap

Claims (5)

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,
Left and right footboards are provided on the left and right side surfaces of the upper frame, respectively, and are rotatable between a horizontal state and a vertical state lifted upward from the horizontal state about axes positioned on the left and right side surfaces. attached,
A drive mechanism for simultaneously operating the left footboard and the right footboard is arranged in a gap between the rear end of the machine body and the front surface of the counterweight,
The drive mechanism is
a drive link configured to be rotatable about a rotation axis;
a driving device for rotating the driving link;
a left connection link that connects the drive link and the left tread plate;
a right connection link that connects the drive link and the right tread plate;
with
the drive link includes a first arm extending in a first direction from the rotation shaft and a second arm extending in a second direction from the rotation shaft;
Of the left connection link, an end on the machine center side is rotatably connected to the tip of the first arm, while an end on the left side of the machine is rotatably connected to the left footboard,
Of the right connection link, the end on the machine center side is rotatably connected to the distal end of the second arm, while the machine right end is rotatably connected to the right tread,
When the left footboard and the right footboard are in the horizontal state, the left connection link connected to the tip of the first arm rotates in a predetermined direction as the driving device is driven. moves to the right side of the machine and the right connecting link connected to the tip of the second arm moves to the left side of the machine, so that the left footboard and the right footboard rotate toward the vertical state,
When the left footboard and the right footboard are in the vertical state, the drive link rotates in a direction opposite to the predetermined direction due to the driving of the drive device. The left connecting link moves to the left side of the machine and the right connecting link connected to the tip of the second arm moves to the right side of the machine, so that the left footboard and the right footboard rotate toward the horizontal state. A construction machine characterized by moving. The driving device is configured as a direct-acting hydraulic actuator,
the drive link further includes a third arm extending in a third direction from the pivot shaft;
An end portion of the hydraulic actuator is rotatably connected to a tip end side of the third arm of the drive link,
2. The construction machine according to claim 1, wherein said driving link is configured to rotate about said rotating shaft as said hydraulic actuator expands and contracts. The hydraulic actuator is arranged above the drive link so that its longitudinal direction is aligned with the vertical direction,
a lower end of the hydraulic actuator is rotatably connected to a tip of the third arm;
The drive link rotates in the predetermined direction when the lower end of the hydraulic actuator expands, and rotates in a direction opposite to the predetermined direction when the lower end of the hydraulic actuator contracts. 3. The construction machine according to claim 2, characterized in that it is constructed as follows. 4. The construction machine according to claim 3, wherein the rod is arranged on the upper side and the cylinder tube is arranged on the lower side of the hydraulic actuator. The left tread is provided with a left connecting member that extends upward from the tread in the horizontal state and is connectable to the machine left end of the left connecting link,
5. The right tread plate is provided with a right connecting member that extends upward from the tread surface in the horizontal state and is connectable to an end portion of the right connecting link on the right side of the machine. The construction machine according to any one of

Images