JPH0447188Y2 - - Google Patents

Description

[Detailed description of the invention] [Purpose of the invention] (Field of industrial application) This invention relates to a counterweight attachment/detachment device for work machines such as truck cranes and shovels that have a removable counterweight.

(Prior Art) Generally, in a truck crane (work machine) having a swivel base, a counterweight is attached to the rear of the swivel base to increase the lifting capacity (by increasing the anti-overturning moment).

Incidentally, such truck cranes have conventionally adopted a structure in which a counterweight can be attached to and detached from a swivel base in order to limit the total weight during traveling or to appropriately distribute weight.

Specifically, as shown in Japanese Unexamined Patent Publication No. 47-44657, a suspension structure using a link mechanism is provided at the rear of the swivel base, and this link is used to rotate the boom mounted on the swivel base. A structure is used in which the counterweight is lifted to the rear of the swivel table by being driven in the vertical direction, and then the counterweight is removably fixed using a fixing means.

(Problems to be Solved by the Invention) However, in a structure in which such a link mechanism is mounted at the rear of the swivel base, there is a risk that the link may jump out rearward due to the rotational movement of the swivel base.

This invention was made with attention to such problems, and its purpose is to provide a counterweight attachment/detachment device for a working machine in which the links of the linkage mechanism do not protrude.

[Structure of the invention] (Means and operations for solving the problems) This counterweight attachment/detachment device includes an extendable arm 33 having engaging portions 34, 41 at its tips, at least on the top of the counterweight 7; 4
0 is provided rotatably along the vertical direction, and engagement receiving parts 19 and 2 are provided on the swivel base 2 and are engageable and detachable from the engagement parts 34 and 41.
1 will be provided. Furthermore, an extendable weight moving member 13 having a weight moving engagement portion 15 at its tip is provided on the swivel base 2 so as to be rotatable in the vertical direction, and a drive source for rotationally driving the weight moving member 13. The device 10 is provided, and the arms 33, 40
In addition to providing link members 36, 36a constituting parallel links that change vertical displacement into rotational displacement of the arms 33, 40 at the base end of the link member 3,
Each arm 33, 40 is driven in the engagement direction by receiving the weight moving engagement part 15 at 6, 36a, and each arm end is connected to each engagement receiving part 19, 21.
By providing a weight moving receiving portion 44 that lifts and fixes the counterweight 7 while engaging with the counterweight 7, the counterweight 7 can be attached and detached using a link mechanism provided on the counterweight 7.

(Example) This invention will be described below based on an example shown in FIGS. 1 to 7. Figure 7 shows a truck crane, where 1 is the vehicle body, 2 is the swivel base, 3 is the telescopic boom, 4 is the hoisting cylinder, 5 is the lifting hook, 6... is the outrigger, and 7 is the counter attached to the rear of the swivel base 2. It's a weight. The counterweight 7 is removably fixed to the swivel base 2 by an attachment/detachment device 8. This invention is adopted in this attachment/detachment device 8, and the structure of its main parts is shown in FIGS. 1 to 6.

That is, the attachment/detachment device 8 includes a link mechanism 9 provided on the counterweight 7 side, and a hydraulic cylinder 10 (corresponding to a drive source device) provided at the rear of the swivel base 2.
The counterweight 7 is attached and detached by the expansion and contraction movement of the hydraulic cylinder 10. In detail, regarding the swivel base 2 side, 11 is an equipment storage part formed in the center of the rear part of the swivel base 2 in the left-right direction and opened in the rear part, and 12 is the equipment storage part 11.
A pair of plate-shaped brackets 13 protruding from the upper opening end of the bracket 13 are rotatably supported via a support pin 14 pivotally supported between the brackets 12, 12, as shown in FIG. This is a weight moving member. The weight moving member 13 includes a pair of spaced apart opposing plate members 13 having a substantially isosceles triangular shape.
a, 13b, with the central apex corner on the lower side, and the apex corner of one side on the previous bracket 12, 12.
It has a structure in which an engaging pin 15 (corresponding to the engaging part for weight movement) is installed between the remaining apex portion on one side, with the support pin 14 serving as a fulcrum. The engagement pin 15 can be extended to the rear of the swivel base 2 or retracted by the vertical rotation. Of course, the length between the pins is determined to be greater than the height of the bracket 12. And, between the apex corner disposed on the lower side of the weight moving member 13 and a point 14a on the bottom side of the equipment housing section 11, which is retracted from the support pin 14 (in the direction toward the front of the swivel base 2). The rod end and cylinder end of the hydraulic cylinder 10 are rotatably connected via a connecting pin 16, and the weight moving member 13 is moved by using the expansion and contraction movement of the hydraulic cylinder 10.
It has a structure that allows it to be rotated. Further, on the left and right sides of the rear upper stage of the swivel base 2, there is provided a support bracket 18 projecting from a pair of spaced apart opposing plate parts, as also shown by the two-dot chain line in FIG. An engagement pin 19 (corresponding to an engagement receiving part) is installed horizontally between the protruding ends of these support brackets 18, 18, so that the upper side of the counterweight 7 can be supported by the exposed pin portion. I have to. In addition, as shown in FIG. 4, a support seat 20 is provided at the center of the bottom open end of the equipment housing portion 11, and is formed by, for example, a pair of plate portions 20a and 20b standing at a predetermined distance. There is. Note that the tip of the support seat 20 slightly protrudes from the rear of the swivel base 2. Approximately semicircular grooves 21 (corresponding to engagement receiving portions) are provided on the upper surfaces of the distal ends of the plate portions 20a and 20b, respectively, so that the lower side of the counterweight 7 can be supported by each of the grooves 21 and 21. I have to.

On the other hand, to explain the structure of the counterweight 7 side, 30 is a weight attachment member attached to the counterweight 7. As shown in FIG. 5, on the side surface of this weight attachment member 30, a pair of ribs 31 (a pair of closely spaced and opposing plate portions 31) are symmetrical and extend vertically on both sides in the width direction.
1a and 31b) are provided in a protruding manner. Then, each rib 3 corresponds to the position of the previous engagement pin 19.
Plate-shaped arms 33 are rotatably supported on the upper portions of 1 and 31 via support pins 32, respectively.
The tip of the arm can be extended to the front side of the weight attachment part 30. In detail, plate parts 31a, 31b
A support pin 32 is pivotally supported between them, and the intermediate portion of the arm 33 is rotatably supported on the exposed pin portion. And each arm 33, 33
A substantially semicircular engagement groove 34 (corresponding to an engagement part) corresponding to the outer shape of the engagement pin 19 is provided at the lower end of the arm 3 with the support pin 32 as a fulcrum.
2, the tip portion where the engagement groove 34 is located can be extended or retracted. In addition,
In order for each arm 33 to operate synchronously, a transmission pin 3 is provided at both ends between the base ends of the arms 33, 33.
5 is rotatably connected by a belt-shaped connecting member 36 that is provided protrudingly. However, each transmission pin 35 passes through a window 37 that has a shape that follows the pin rotation locus (trajectory determined by the predetermined maximum and minimum rotation ranges of the arm 33) provided on the inner plate portion 31b. and is rotatably connected to the arm 34.

On the other hand, at the center of the lower part of the side surface of the weight attachment part 30, ribs 38, 38 which are opposed to each other and spaced from each other are provided to protrude in the vertical direction, as shown in FIG. Further, a fulcrum pin 39 is pivotally supported between the lower portions of the ribs 38, 38, passing through the ribs 38, 38. At the center of this fulcrum pin 39, two plate members 40 each having a substantially isosceles triangle shape are attached.
An arm 40 consisting of a and 40b is rotatably supported, and the end of the arm can extend toward the front side of the weight attachment member 30. In other words, the plate members 40a and 40b are arranged with the central apex portion on the lower side.
The center thereof is rotatably supported by a pin portion between the ribs 38, 38. And this plate member 40a,
An engagement pin 41 (corresponding to an engagement part) is installed between the apex portions of the tips of 40b, and the engagement pin 41 is pulled forward of the weight attachment member 30 by vertical rotation about the fulcrum pin 39. It allows people to come out and evacuate. Of course, the length between the pins is set to be longer than the height of the ribs 38. Further, an auxiliary arm 42 is rotatably connected between the ends of each engagement pin 41 and the fulcrum pin 39, and the pin portion exposed between the auxiliary arm 42 and the arm 40 is engaged with and disengaged from the groove 21. It is specified in the section.

A band-shaped connecting member 3 is provided between the remaining rear apex corners of the plate members 40a and 40b, protruding from the lower part of the widthwise center of the connecting member 36 in the vertical direction.
6a (which constitutes the link member together with the connecting member 36) is rotatably connected via the connecting pin 43, and the mutual members (arm 3
3. The connecting member 36a and the arm 40) constitute a parallel link (link mechanism). In other words,
When a force is applied to the connecting member 36a to move it upward, the parallel arms 33 and 40 rotate clockwise as shown in FIG. The weight of the member causes it to rotate counterclockwise and retreat.

In addition, as shown in FIGS. 1 and 6, an engagement pin is provided on the middle front part of the connecting member 36a along a diagonally downward direction corresponding to the rotation locus of the engagement pin 15 on the swivel base 2 side. 15 is provided with an engagement groove 44 (corresponding to a weight moving receiving part) that can be freely engaged and disengaged. The depth of the engagement groove 44 is set to a predetermined value, and after placing the counterweight 7 adjacent to the rear part of the swivel base 2, the hydraulic cylinder 10 is extended and the engagement pin 15a is inserted into the engagement groove 44. By engaging the engagement pin 41 with the groove 21 and the engagement groove 34 with the engagement pin 19, the counterweight 7 can be lifted and fixed to the rear of the swivel base 2. I have to. Note that the plate members 13a, which constitute the weight moving member 13,
A hole 49a for inserting a stopper pin is provided in the central plate portion of the plate 13b, and after the counterweight 7 is placed in the desired position on the swivel base 2, the hole 49a provided in advance at the fixed position of the brackets 12, 12 is inserted. Part 49
By inserting the stopper pin 45 into the hole 49a, the counterweight 7 is fixed.

In addition, the attachment/detachment device 8 is configured to move the weight attachment member 30 from the position of the support pin 14 as shown in FIG.
The engagement groove 44 and the engagement pin 15 are made to engage with each other at a point as far away as possible. Specifically, as shown in FIG.
is set at a point on the counterweight 7 side that is l away from the support pin 14, so that the acting force is increased by the principle of leverage (l>0).

Note that a recess 46 is formed on the rear lower surface of the swivel base 2, and the weight attachment member 30 is fitted into the recess 46 of the swivel base 2 when the weight attachment member 30 is connected to the swivel base 2. A protrusion 47 is provided.

Therefore, when attaching the counterweight 7 to the swivel base 2 using such an attachment/detachment device 8, the counterweight 7 is placed at a predetermined position on the vehicle body 1 as shown in FIG. The swivel base 2 is rotated and positioned so that the rear part faces the weight attachment member 30. At this time, each arm 33, 40 is in a retracted state in which it is rotated upward by the weight of the connecting members 36, 36a, as shown in FIG. More specifically, the connecting member 36
The lower surface of the weight mounting member 30 comes into contact with the upper surface of the horizontal rib 48 protruding from the middle of the side surface of the weight mounting member 30, thereby maintaining the stored state.

After this, the contracted hydraulic cylinder 10 is expanded. As a result, the weight moving member 13 rotates clockwise about the support pin 14 and engages with the engagement groove 44. Then, in conjunction with this, the connecting member 36a rises, causing both the upper and lower arms 33, 40 to rotate clockwise. In other words, the arms 33 and 40 are extended toward the swivel base 2 side. Due to this overhang, the engagement groove 34 at the tip of the arm on the upper stage gradually engages with the engagement pin 19 on the upper stage of the swivel base 2, and the engagement pin 41 at the end of the arm on the lower stage gradually engages with the engagement pin 19 on the upper stage of the swivel base 2.
becomes involved. At this time, the protrusion 47
The weight mounting member 30 is then positioned.

Here, due to such engagement, a force is applied to the link mechanism in the upward direction using the respective engagement pins 19 and the grooves 21 as fulcrums, so that the counterweight 7 is lifted from the vehicle body 1 together with the weight attachment member 30, 2, approaching the rear. of course,
The tip of each arm slides around the engagement pin 19 and the groove 21. Then, when the arms 33 and 40 pass through the horizontal state and reach a predetermined state thereafter, the weight attachment member 30 is fixed to the rear part of the swivel base 2. Thereafter, the counterweight 7 is fixed by inserting the stopper pin 45 into the hole 49a of the weight moving member 13 to prevent accidental movement, and the installation of the counterweight 7 is completed. In addition, when removing the counterweight 7, the stopper pin 45 may be pulled out and the hydraulic cylinder 10 may be contracted.

Thus, in the structure for attaching and detaching the counterweight 7 to and from the swivel base 2, the link mechanism is connected to the swivel base 2.
Therefore, if the members constituting the link mechanism fly out due to the rotation of the swivel base 2, there will be no damage. Furthermore, since the link mechanism is eliminated from the swivel base 2, the overhang of the rear portion of the swivel base 2 can be reduced accordingly, bringing about the advantage that the turning radius can be reduced. Moreover, the weight of the swivel base 2 can be reduced by the weight of the link mechanism.

In addition, in one embodiment, two (plural) arms 33, 4 which also serve as part of the parallel link of the lower arm.
0, but the lower arm may function only as a link (does not engage), and the counterweight may be attached or detached by rotating only the upper arm.

Further, in one embodiment, this invention is applied to a truck crane, but the invention is not limited to this, and may be applied to a working machine having a swivel base, such as a shovel. Of course, the present invention is not limited to self-propelled machines, and may be applied to non-self-propelled working machines that require disassembly and assembly.

[Effects of the invention] As explained above, according to this invention, the counterweight can be attached and detached using a link mechanism provided on the counterweight.

Therefore, since the link mechanism is removed from the swivel base, it is possible to prevent the link from popping out from the swivel base. Furthermore, since the overhang at the rear of the turning table can be reduced by that much, the turning radius can be reduced. Moreover, there is an advantage that the weight of the swivel base can be reduced by the weight of the link.

[Brief explanation of the drawing]

Figures 1 to 7 show one embodiment of this invention, Figure 1 is a side sectional view showing the main part of the counterweight attachment/detachment structure together with the state in which the weight is fixed, and Figure 2 is the first embodiment of the invention. - A cross-sectional plan view of the upper arm along line A, Figure 3 is a cross-sectional view of the weight moving member around line B-B in Figure 1, and Figure 4 is a cross-sectional view of the area around the weight moving member along line C-C in Figure 1. A cross-sectional plan view of the lower arm area, Fig. 5 is a side view showing the link mechanism provided on the counterweight, Fig. 6 is a side view showing the state in which the counterweight is removed, and Fig. 7 is a vehicle to which this invention is applied. FIG. 3 is a side view of the crane. 2...Swivel base, 7...Counterweight, 8
... Attachment/detaching device, 10... Hydraulic cylinder (drive source device), 13... Weight moving member, 15... Engagement pin (weight moving engagement part), 19, 21...
...Engagement pin, groove (engagement receiving part), 30... Weight mounting member, 33, 40... Arm, 34, 41...
...Engagement groove, engagement pin (engagement part), 36, 36a...
...Connecting member (link member), 44... Engagement groove (weight movement receiving part).

Claims (1)

[Scope of utility model registration request] A work machine having a swivel base on which a work machine device is mounted, a counterweight disposed on the swivel base, and an engaging portion at the tip of the counterweight provided at least in an upper part thereof so as to be rotatable along a vertical direction. an arm that can be extended; an engagement receiving part that can be engaged with and disengaged from the engagement part provided on the swivel base in correspondence with the arm; an extendable weight moving member having a weight moving engagement portion at its distal end; a drive source device provided on a rotating base for rotationally driving the weight moving member; and a drive source device connected to the base end of the arm. a link member that forms a parallel link and changes vertical displacement into rotational displacement of the arm; and an arm end that drives the arm in the engaging direction by receiving the weight moving engagement portion provided on the link member. A counterweight attaching/detaching device for a working machine, comprising: a weight moving receiving part that engages with the engaging receiving part to lift the counterweight and fix it to a swivel base.