JP6742261B2 - Construction machinery - Google Patents

Description

The present invention relates to a construction machine having a pair of left and right side frames.

Generally, a crawler type construction machine such as a crawler crane or a hydraulic excavator includes a lower traveling body having a pair of left and right side frames, and an upper revolving body provided above the lower traveling body so as to be rotatable. Some of such crawler type construction machines are provided with a lower weight between the side frames in order to stabilize the machine body. Further, some construction machines of this type have a function of expanding or contracting the interval between the left and right side frames in order to suit the application or further improve the stability of the machine body (for example, refer to Patent Document 1).

FIG. 15 is a perspective view showing an example of a lower traveling body of a construction machine according to a conventional technique. As shown in the figure, the lower weight 101 of the lower traveling body 1 in the prior art is positioned below the first and second pair of upper weights 103A and 103B and the first and second upper weights 103A and 103B. However, the lower weight 105, which is connected to these by a bolt, is provided, and these are provided as a pair in front of and behind the car body 21.

FIG. 15 shows a state in which the side frame 32 of the lower traveling body 1 is most expanded. In this state, the first and second upper weights 103A and 103B are bolted to both ends of the lower weight 105 by large-diameter bolts. Also, in the drawings of the first and second upper weights 103A and 103B, the front corners are cut diagonally to avoid interference with the lower boom 5A when the lower boom 5A (FIG. 1) is stored during assembly/disassembly. Missing. That is, in the drawings of the first and second upper weights 103A and 103B, the central portions of the corners on the front side are the first and second cutout portions 103A1 and 103B1. The length dimension in the direction orthogonal to the side frame 32 including the first and second cutout portions 103A1 and 103B1 and the space portion therebetween is set according to the width dimension of the lower boom 5A.

In the lower weight 101 according to the related art, as shown in FIG. 15, each of the front side and the rear side is composed of three members. When the width of the side frame 32 is reduced, the first and second upper weights 103A and 103B are formed. It is necessary to lift each of them by a crane, remove the bolt to change the position to the inside, and then retighten the bolt by aligning the bolt with the bolt hole of the lower weight 105. When changing from the contracted position to the expanded position, the reverse operation is performed. It is necessary to carry out this reduction and expansion work at two locations before and after.

Japanese Patent No. 4619147

As described above, conventionally, when the width of the side frame is reduced or expanded, it is necessary to perform the contraction and expansion work of the first and second upper weights 103A and 103B at the front and rear two places each time. Was incurring a decline. This reduction in work efficiency leads to a longer assembly time on site, and therefore a construction machine equipped with a lower weight that can be assembled and disassembled in a short time has been desired.

Therefore, the problem to be solved by the present invention is to provide a construction machine equipped with a lower weight that can be assembled and disassembled in a short time without the need to remove and attach the lower weight when reducing and expanding the side frame. is there.

In order to solve the above-mentioned problems, one aspect of the present invention has a pair of side frames provided on both sides in the width direction of a car body so as to be capable of reducing and expanding the width direction interval, and arranged between the pair of side frames. and a lower weights are includes upper weights the lower weights are mounted on the lower weight and the lower weight, a construction machine to which the lower weights are supported by the front Symbol carbody, the width of the upper weight on both sides of the direction, the a pair of open use state when the side frame is extended, the be obtained Bei each side step set in closed storage state along the side face of the upper weight when reduced Is characterized by.

According to one aspect of the present invention, it is possible to provide a construction machine provided with a lower weight that can be assembled and disassembled in a short time without removing and attaching the lower weight when the side frame is contracted and expanded. In addition, problems, configurations, and effects other than the above will be clarified in the following description of the embodiments.

It is a side view showing the whole composition of a crawler crane as a work device with a crawler concerning an embodiment of the present invention. It is a principal part perspective view which shows the lower traveling body and the upper revolving superstructure part of the crawler crane of FIG. FIG. 2 is a perspective view of a lower traveling body from which the upper swing body of the crawler crane of FIG. 1 has been removed. It is the perspective view which looked at the lower weight of the crawler crane of Drawing 1 from the car body side. It is a figure which shows the side step of the lower weight of FIG. 4, the figure (a) shows the state at the time of using the side step, and the figure (b) shows the state at the time of storing the side step. FIG. 6 is a perspective view showing a relationship between a lock pin to be mounted when the side step of FIG. 5A is used and the side step, as viewed from the lower right side of the side step. It is a perspective view which shows the relationship between the lock pin attached when using the side step of FIG.5(a), and a side step, and is the figure seen from the lower left side with respect to the side step. FIG. 5 is a perspective view of an essential part showing a mounting part of the lower weight of FIG. 4 to the jack-up device. FIG. 5 is a side view of a cross section of a main part showing a state when the attachment of the lower weight of FIG. 4 to the jackup device is completed. FIG. 5 is a side view showing a cross section of a main part showing a relationship between the lower weight and the jackup device when the lower weight of FIG. 4 is attached to the jackup device. FIG. 2 is a side view in which a main part is shown in a cross-sectional view showing an assembled/disassembled state in which a lower boom of the crawler crane shown in FIG. 1 is folded. It is a top view which compares and shows the state at the time of reduction of the side frame at the time of using the lower weight manufactured by the conventional casting, and the lower weight manufactured by the can manufacturing which concerns on this embodiment. 12A and 12B are front views showing a comparison between the conventional configuration shown in FIG. 12 and the configuration of the present embodiment. FIG. 12A shows the conventional configuration and FIG. 12B shows the configuration of the present embodiment. It is a perspective view which shows an example of the lower traveling body of the construction machine in a prior art.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a side view showing the overall configuration of a crawler crane as a construction machine according to an embodiment of the present invention. The crawler crane 100 basically includes a lower traveling structure 1, an upper revolving structure 3, a boom 5, and a counterweight 7. The upper-part turning body 3 is rotatably provided on the lower-part traveling body 1 via turning wheels 9. The boom 5 includes a lower boom 5A, an intermediate boom 5B and an upper boom 5C, and is pivotally supported by the upper revolving structure 3 so as to be capable of hoisting. A cab (driver's cab) 11 is installed at an end of the upper swing body 3 opposite to the side where the counterweight 7 is installed, and a swing frame 13 is provided between the cab 11 and the counterweight 7.

The revolving frame 13 is equipped with a hoisting drum which is a winch drum for hoisting, and a hoisting drum which is a winch drum for hoisting. A hoisting rope is wound around the hoisting drum, and the hoisting rope is wound or unwound by driving the hoisting drum, and a hook hung at the tip of the boom 5 moves up and down. A hoisting rope 15 is wound around the hoisting drum, and the hoisting rope 15 is wound or unwound on the hoisting drum by driving the hoisting drum, and the boom 5 connected via the mast 14 and the pendant rope 16 is hoisted.

Further, a front winch wire rope 17A and a rear winch wire rope 18A respectively hang from the tip of the upper boom 5C, and a boom hook 17 and an auxiliary sheave hook 18 hang downwardly from the lower ends thereof. A hydraulic motor for a front winch drum, a hydraulic motor for a rear winch drum, and a hydraulic motor for ups and downs are installed in the revolving frame 13. The front winch drum is driven by a front winch drum hydraulic motor. The rear winch drum is driven by a hydraulic motor for the rear winch drum. The hoisting drum is driven by a hoisting hydraulic motor. In addition, a hydraulic motor for the front winch drum, a hydraulic motor for the rear winch drum, a hydraulic motor for undulation, and a brake device for braking the hydraulic motor for undulation are provided for each hydraulic motor.

FIG. 2 is a perspective view of essential parts showing the lower traveling body 1 and the upper revolving structure 3 of the crawler crane 100, and FIG. 3 is a perspective view of the lower traveling structure 1 with the upper revolving structure 3 removed. 2 and 3, the lower traveling body 1 includes a car body 21 also called a lower frame and a pair of crawlers 31. A total of four adapters 22 are provided on the left and right sides of the front and rear portions of the car body 21, respectively. By attaching and detaching each adapter 22, the space between the side frames 32 can be reduced and expanded. A pair of jack-up devices 38 for jacking up the lower traveling body 1 are provided at the front and rear of the car body 21.

The crawler (traveling device) 31 is of a so-called crawler type and is attached to the right front and right rear adapters 22 and the left front and left rear adapters 22, respectively. The crawler 31 is wound around a side frame (crawler side frame) 32, a drive wheel 33 and a driven wheel 34 of a driving device for traveling, an upper roller, a lower roller 36, and the drive wheel 33 and the driven wheel 34. A crawler belt (crawler belt) 37 is provided. The traveling drive device includes drive wheels (sprocket) rotatably supported near the rear ends of the side frames 32, and a traveling hydraulic motor that drives the drive wheels.

FIG. 4 is a perspective view of the lower weight 40 as viewed from the car body 21 side. Lower weights 40 as shown in FIG. 4 are attached to the car body 21 via a jack-up device 38 on the front side and the rear side of the crawler crane 100, respectively. The lower weight 40 includes an upper stage weight 42 and a lower stage weight 44. That is, the lower weight 40 has a structure in which the upper weight 42 and the lower weight 44 are vertically stacked. The upper weight 42 and the lower weight 44 are can-made products, which are manufactured by cutting a steel material, welding it, and plastically deforming it.

As shown in FIG. 3, the upper weight 42 has a stepped notch 42A formed in the central portion thereof, and the front side of the lower weight 44 projects from the front surface 42B of the upper weight 42 to form a three-step staircase. There is. Further, a flip-up step 44B is attached to the front surface 44A of the lower weight 44, and the step 44B can easily go up from the step 44B to the upper surface 42F of the upper weight 42 through the upper surface 44J of the lower weight 44. The lower weight 40 shown in FIG. 3 and the lower weight 40 on the rear side are also arranged symmetrically with the car body 21 interposed therebetween, and are attached to the jack-up device 38. The cutout portion 42A is set to have a width that will not interfere with the upper weight 42 when the lower boom 5A is tilted forward, which will be described later. Further, the depth of the cutout portion 42A is set to a height that does not interfere with the upper weight 42 when the tip portion of the lower boom 5A is at the same height as the ground. The upper end 44H on the front side of the lower weight 44 is also set to a height and a protruding dimension that do not interfere with each other when the height and the protruding dimension on the front side of the lower boom 5A are equal to the ground. The front side of the front-side upper end portion 44H means the side of the lower weight 44 away from the car body 21.

The lower weight 44 of the lower weight 40 is provided with a mounting portion 46 to the jackup device 38, a link 48 for connecting to the upper weight 42, and a lower ladder 50. The mounting portion 46 includes a mounting bracket 46A, a support pin 46B, and a disengagement prevention pin 46C. The mounting bracket 46A is integrally provided by welding a pair of parallel plate members 46A1 to the inner surface 44C of the lower weight 44. The mounting brackets 46</b>A are respectively provided at the left and right end portions of the inner surface 44</b>C of the lower weight 44 at positions facing the jackup devices 38. The support pin 46B is installed on the upper part of the mounting bracket 46A between the pair of parallel plate members 46A1 so as not to be retained by, for example, a retaining ring 46E. The inner surface 44C means the surface on the car body 21 side.

An insertion hole 46D for the retaining pin 46C is formed below the support pin 46B. The support pin 46B is fitted into the insertion hole 46D at a predetermined position of the guide groove 38B of the jack-up device 38. At this time, the lower weight 40 tries to rotate counterclockwise with the support pin 46B as the center of rotation. By supporting this with the contact bolt 38E, it matches with the retaining hole 38C formed on the jack-up device 38 side. Then, the retaining pin 46C is inserted from the side portion of the insertion hole 46D to the insertion hole 46D of the pair of parallel plate members 46A1. As a result, the lower weight 40 is attached to the jackup device 38. The lower ladder 50 is provided substantially at the center of the inner surface 44C of the lower weight 44.

The outer edge shapes of the inner surface 42C, the slope 42D and the side surface 42E of the upper weight 42 and the inner surface 44C, the slope 44D and the side surface 44E of the lower weight 44 are the protrusions of the front surface 42B of the upper weight 42 forming the steps of the lower weight 44. Except for the part, they are formed almost the same. As a result, the inner surfaces 42C and 44C, the inclined surfaces 42D and 44D, and the side surfaces 42E and 44E are substantially flush with each other when superposed. Foldable side steps 43 are provided on the side surfaces 42E on both sides of the upper weight 42. The side step 43 functions as a bridge between the side frame 32 and the upper surface of the crawler belt 37 when the side frame 32 is expanded. In addition, when the upper weight 42 is overlapped with the lower weight 44, at least both width dimensions (dimensions in the direction orthogonal to the side frame) are set to the same width dimension in consideration of a manufacturing error. ing.

An upper ladder 54 is provided at a position of the upper weight 42 that abuts the upper portion of the lower ladder 50. The upper ladder 54 is divided into the upper ladder 42 and the lower weight 44 because a series of the lower ladder 50 and the lower ladder 50 are divided and fixed to the inner surfaces 42C and 44C of the upper weight 42 and the lower weight 44, respectively. It was done. By providing the lower ladder 50 and the upper ladder 54 in this way, it is possible to use both of them to move between the ground and the upper surface 42F of the upper weight 42. It is also possible to move from the ground to the upper surface of the car body 21, the crawler belt 37, etc. through the upper surface 42F of the upper weight 42.

A pair of hanging lug storage spaces 42G are formed on the upper surface 42F of the upper weight 42. The suspension lug storage space 42G is formed by further notching in the direction of the inner surface 42C from both side surfaces of the notch portion 42A. A pair of first suspension lugs 42H1 are provided on the surface located inside the suspension lug storage space 42G along the vertical surface of the cutout portion 42A. Further, a pair of second suspension lugs 42H2 are provided on a surface located outside the suspension lug storage space 42G at a position further inward from the vertical surface of the cutout portion 42A in the inner surface 42C direction. .. The first suspension lug 42H1 and the second suspension lug 42H2 are arranged in parallel with each other. The first suspension lug 42H1 is used when lifting the lower weight 40 in a state where the upper weight 42 and the lower weight 44 are connected. The second suspension lug 42H2 is used when only the upper weight 42 is suspended. When the first suspension lug 42H1 is used, the connected upper and lower weights 42 and 44 are hung while maintaining a predetermined angle at which the lower and upper ladders 50 and 54 are lowered, for example, around 3 degrees. .. When using the second suspension lug 42H2, the upper weight 42 is suspended in a horizontal state. The first and second suspension lugs 42H1 and 42H2 are respectively provided at positions that are in the state of the predetermined angle and in the horizontal state in consideration of the center of gravity.

5A and 5B are views showing the side step 43. FIG. 5A shows a state when the side step is used, and FIG. 5B shows a state when the side step is stored. 6 and 7 are perspective views showing the relationship between the lock pin 43A and the side step 43 to be mounted when the side step 43 of FIG. 5(a) is used. In FIG. 6, the link 48 shows a state in which the upper weight 42 and the lower weight 44 are connected. In FIG. 5, the side step 43 is rotatably supported by a support shaft 42K on a side step mounting bracket 42J protruding from the upper end of the side surface 42E of the upper weight 42. The side step mounting bracket 42J is formed with a storage insertion hole 42L through which the lock pin 43A is inserted when the side step 43 is stored. The end surface of the side step mounting bracket 42J with which the lock pin 43A abuts when the side step 43 is used functions as a support portion 42M that supports the weight of the side step 43 and the operator who uses the side step 43.

A rib 43B as a reinforcing portion is provided on the back surface of the side step 43, and a side step supporting bracket 43C is provided at a position of the rib 43B corresponding to the side step mounting bracket 42J. The side step support bracket 43C is provided with a support shaft mounting hole 43D in which the support shaft 42K is mounted, a lock pin insertion hole 43E in which the lock pin 43A is inserted, and a positioning pin 43F for positioning the lock pin 43A. ing. The lock pin 43A includes a pin body 43A1 and a flange 43A2 provided at one end of the pin body 43A1, and the flange 43A2 is formed with a positioning hole 43A3 to be inserted into the positioning pin 43F. The positioning pin 43F has a retaining pin insertion hole 43F1 into which the retaining pin 43G is inserted.

When the side step 43 is used, the pin body 43A1 of the lock pin 43A is inserted into the lock pin insertion hole 43E in the state shown in FIGS. 6 and 7 in which the side step 43 is raised. At that time, the positioning hole 43A3 formed in the flange 43A2 is externally fitted to the positioning pin 43F. When the flange 43A2 is positioned closer to the side step support bracket 43C than the retaining pin insertion hole 43F1, the retaining pin 43G is inserted into the retaining pin insertion hole 43F1. As a result, as shown in FIG. 5A, the lock pin 43A is positioned and prevented from coming off when the side step 43 is used. At this time, the lock pin 43A contacts the support portion 42M on the end surface of the side step mounting bracket 42J, and holds the side step 43 in use.

The side step 43 is housed at a position along the side surface 42E of the upper weight 42 when not in use, as shown in FIG. 5B. At that time, the lock pin 43A is pulled out from the lock pin insertion hole 43E and inserted into the lock pin insertion hole 43E that matches the storage insertion hole 42L at the storage position. Then, the positioning hole 43A3 is inserted in alignment with the positioning pin 43F, and when the flange 43A2 is positioned closer to the side step support bracket 43C than the retaining pin inserting hole 43F1, the retaining pin 43G is inserted into the retaining pin inserting hole 43F1. insert. As a result, as shown in FIG. 5B, the lock pin 43A is positioned and prevented from coming off when the side step 43 is stored.

As shown in FIG. 6, the link 48 includes first and second protrusions 48A and 48B erected on the lower weight 44, a third protrusion 48C erected on the upper weight 42, and first and second protrusions 48C. A protrusion 48A, 48B, or a connecting member 48D hung between the first and third protrusions 48A, 48C, and first to third rings formed on the first to third protrusions 48A, 48B, 48C, respectively. The first and second ring pins 48E1 and 48E2 that can be inserted into the pin insertion holes 48A1, 48B1 and 48C1. A projection 44F for relative positioning and a projection insertion hole 42N are formed between the upper weight 42 and the lower weight 44 (FIG. 9), and the upper weight 42 is attached to the lower weight 44 and the projection 44F. When the protrusion insertion holes 42N are aligned and overlapped, the link 48 is positioned at the connecting position shown in FIG. Note that FIG. 4 shows the state of the link 48 when not connected.

In the unconnected state immediately after the upper weight 42 is overlaid on the lower weight 44, the connecting member 48D is mounted between the first protrusion 48A and the second protrusion 48B of the lower weight 44 as shown in FIG. ing. To change from the non-connected state to the connected state, the first and second ring pins 48E1 and 48E2 are pulled out from the first and second ring pin insertion holes 48A1 and 48B1, and the connecting member 48D is moved to the first and second. The protrusions 48A and 48B are removed. Next, the connecting member 48D is attached to the first protrusion 48A on the lower weight 44 side and the third protrusion 48C on the upper weight 42 side, and the first ring pin 48E1 is inserted into the first ring pin insertion hole 48A1. The second ring pin 48E2 is inserted into the third link pin insertion hole 48C1. This is done for the four links 48. As a result, the upper weight 42 is superposed on the lower weight 44, and is connected at four points and can be handled integrally.

FIG. 8 is a perspective view of an essential part showing a mounting portion 46 of the lower weight 40 to the jackup device 38. An attachment portion 46 is provided on the inner surface 44C of the lower weight 44 as shown in FIG. In the mounting portion 46, the support pin 46B is fitted into and supported by the guide groove 38B formed in the guide plate 38A on the jack-up device 38 side. At this time, the lower weight 40 tries to rotate counterclockwise with the support pin 46B as the center of rotation. By supporting this with the contact bolt 38E, the retaining hole 38C and the insertion hole 46D of the mounting bracket 46A are aligned. Then, the retaining pin 46C is inserted into the insertion hole 46D formed in the pair of parallel plate members 46A1 of the mounting bracket 46A and the retaining hole 38C formed in the guide plate 38A. Next, when the retaining pin 46C reaches the holding completion position, the retaining pin 46C1 is inserted into the retaining pin insertion hole formed in the retaining pin 46C, so that the lower weight 40 is attached to the jack-up device 38. Complete.

FIG. 9 is a side view showing a state in which the lower weight 40 is completely attached to the jack-up device 38, and is a cross-sectional view of a main part. In this state, the support pin 46B is fitted in the guide groove 38B formed in the guide plate 38A, and the retaining pin 46C is inserted in the retaining hole 38C. In this state, the retaining pin 46C1 is inserted into the retaining pin insertion hole to perform retaining treatment, and the lower weight 40 can be securely attached to the jack-up device 38.

FIG. 10 is a cross-sectional side view of a main part showing the relationship between the lower weight 40 and the jackup device 38 when the lower weight 40 is attached to the jackup device 38. In this state, the lower weight 40 is lifted to the position where the support pin 46B is higher than the portion where the guide groove 38B is formed by the first hanging lug 42H1, and the lower side and the upper side of the lower weight 40 on which the ladders 50 and 54 are attached are set in advance. It is hung down and attached in a tilted state so that it is inclined at a predetermined angle, for example, about 3 degrees. At that time, the support pin 46B contacts the guide surface 38D formed on the end surface of the guide plate 38A, and is guided to the guide groove 38B along the guide surface 38D when the lower weight 40 is suspended. Then, when the support pin 46B is fitted into the deepest portion of the guide groove 38B and further hung, the lower weight 40 rotates counterclockwise around the support pin 46B in FIG. By this rotation, when the stopper 44G of the lower weight 44 comes into contact with the contact bolt 38E on the jack-up device 38 side, the positions of the disengagement prevention hole 38C and the insertion hole 46D are aligned, as shown in FIG. At this position, the stopper pin 46C is inserted from the stopper hole 38C side, and when the stopper pin 46C is inserted beyond the insertion hole 46D to the stopper hole 38C on the opposite side, the lower weight 40 is jacked up as described with reference to FIG. It will be attached to the device 38.

FIG. 11 is a side view in which a main part of the crawler crane 100 is shown in an assembled and disassembled state. This figure is for explaining that there is no interference with the lower weight 40 when the lower boom 5A is folded to the transportation state. That is, as shown in FIGS. 2 and 3, the upper weight 42 of the lower weight 40 is formed with a stepped notch 42A in the central portion, and the front side of the lower weight 44 projects from the front surface 42B of the upper weight 42. The three steps are stacked to form a staircase. The front upper end portion 44H on the lower weight 44 side of the stairs, the front upper end portion 42P of the cutout portion 42A of the upper step weight 42, and the front upper end portion 42Q of the upper surface 42F of the upper step weight 42 support the lower boom 5A on the ground (the crawler belt 37). It is set so that it will not interfere when it is tilted to the same level. As a result, even when the lower boom 5A is tilted to be assembled/disassembled, the lower boom 5A and the lower weight 40 do not interfere with each other, as in the case of the conventional technique shown in FIG.

FIG. 12 shows a state in which the side frame 32 is contracted and expanded when the lower weight 101 manufactured by conventional casting and the lower weight 40 manufactured by the can making according to the present embodiment are used. It is a top view. In the same figure, from the line L1 indicating the center in the horizontal direction, the lower side is the state when the side frame is contracted and the upper side is the state when the side frame is expanded. The configuration of the form is shown. Conventionally, at the time of reduction, the bolts of the first and second upper weights 103A and 103B are removed, the first and second upper weights 103A and 103B are respectively lifted and moved to the inside of the lower weight 105, and the lower weight 105 The positions of the first and second upper weights 103A and 103B are changed by inserting and tightening bolts into the inner bolt holes. Then, after this position change, the work of reducing the side frame 32 to, for example, the transportation width is performed.

On the other hand, in the present embodiment, the upper weight 42 and the lower weight 44 of the lower weight 40 are each configured by one can-making product, and the upper weight 42 is superposed on the lower weight 44 and the link 48 is used to both Are integrated by connecting. When the side frame 32 is contracted, the side step 43 is folded as shown in the lower right part of FIG. 12, and when expanded, the side step 43 is set in the use position as shown in the upper right part of the figure. The lock pin 43A may be used to lock the position. Therefore, in the present embodiment, it is not necessary to remove the first and second upper weights 103A and 103B that are divided as in the conventional case, nor to move the inner weights or the outer weights to attach them. That is, when the side frame 32 is contracted and expanded, in this embodiment, only the opening and closing of the side step 43 is required. On the other hand, in the case of using the conventional two-divided first and second upper weights 103A and 103B, it is necessary to rearrange the first and second upper weights 103A and 103B when the side frame 32 is reduced and expanded. There is. As a result, in the present embodiment, the work efficiency can be greatly improved as compared with the related art.

FIG. 13 is a front view showing a comparison between the conventional configuration shown in FIG. 12 and the configuration of the present embodiment. FIG. 13 shows a state in which the side frame 32 is expanded. FIG. 13A shows the conventional configuration, and FIG. 13B shows the configuration of the present embodiment. As shown in FIG. 13, in the conventional configuration, when the side frame 32 is expanded, a space portion 107 is formed in the central portion, and the first and second cutout portions 103A1, which are slopes, are formed on both sides of the space portion 107. 103B1 is formed. Therefore, when the worker moves on the upper surface of the lower weight 101, he/she may step out of the foot in the space 107, and may be slipped by the foot of the slopes of the first and second cutouts 103A1 and 103B1. There is. However, in the present embodiment, the one side step 43 to the other side step 43 are formed in a plane, and the stepped notch 42A is present in the central portion, but the notch 42A is a plane and There is no risk of being taken and slipping. Therefore, the safety for the worker can be improved.

In addition, since the lower weight 40 according to the present embodiment is a can-making product and has a space formed therein, heavy materials such as steel materials and slag are stored in the space and the weight is added to add weight. Function as. Since each part of the lower weight 40 is a can-made product, a steel plate can be molded and welded as a whole to be inexpensively manufactured as an integrated product without using a mold unlike a cast product. On the other hand, in the prior art, since the lower weight 101 is a cast product, the protrusions, the attachment portions, etc. attached to the main body are attached by bolting, and are configured as one body. Therefore, there are problems that it takes a long time to attach the bolts, the bolts may be loosened, and a mold is required, which makes the bolt expensive. However, if the lower weight 40 is made of a can-made product as in the present embodiment, these problems can be solved.

As described above, according to this embodiment, the following effects are obtained. In the following description, correspondence is made between each component in the claims and each part of the present embodiment, and when the terms of the two are different, the former is shown in parentheses and the corresponding reference numerals are given. The relationship between the two was clarified.

In the present embodiment, a pair of side frames 32 that are provided on both sides in the width direction of the car body 21 so as to be able to reduce and expand the interval in the width direction, and a lower weight 40 that is arranged between the pair of side frames 32. , The lower weight 40 includes a lower stage weight 44 and an upper stage weight 42 mounted on the lower stage weight 44, and the lower weight 40 is supported by the car body 21 via the lower stage weight 44. In the (construction machine) 100, each of the lower weight 44 and the upper weight 42 is made of a single member having the same dimension in the width direction, and the pair of side surfaces 42E (both side surfaces in the width direction) of the pair of the upper weight 42 and the pair of Each side frame 32 is opened when the side frame 32 is expanded to be used, and is closed when the side frame 32 is contracted to be set to the retracted state. The upper weight 42 is connected to the lower weight 44 by a connecting member 48D. It is configured to be connected by.

With such a configuration, it is not necessary to remove the upper weight 42 and adjust the position when the width of the side frame 32 is narrowed or expanded, so that the upper weight 42 need not be removed and reattached. Becomes As a result, work efficiency can be improved. That is, it is only necessary to fold the side step 43 to be in the stored state at the time of contraction and to open it at the time of expansion to be in the use state, which enables efficient work. Further, it is possible to reduce a gap generated between the lower weight 40 and the crawler 31 when the side frame 32 is expanded. As a result, the worker can easily move between the lower weight 40 and the crawler 31 and can contribute to the improvement of safety during work.

In the present embodiment, the connecting member 48D is fitted into the first and third protrusions (protrusions) 48A, 48C protruding from the side surfaces 42E, 44E of the lower weight 44 and the upper weight 42, respectively, and The third protrusions 48A and 48C are connected to each other.

According to this structure, the work of attaching the upper weight 42 to the lower weight 44 only needs to be performed by stacking the upper weight 42 and the lower weight 44 on top of each other and connecting them by the connecting member 4D. Therefore, the upper weight 42 and the lower weight 44 can be integrated.

In the present embodiment, the first and second suspension lugs are provided with the first and second suspension lugs (suspension members) 42H1 and 42H2 arranged in the suspension lug storage space (position) 42G retracted from the upper surface 42F of the upper weight 42. The (hanging member) 42H1 is provided at a position inclined at a preset angle when the upper weight 42 is connected to the lower weight 44 and attached to the car body 21 side, and the second hanging lug (hanging member) 42H2 is the upper stage. When the weight 42 is attached to the lower weight 44, the weight 42 is provided at a horizontal position.

According to this structure, when the upper weight 42 is connected to the lower weight 44 and is attached to the car body 21 side, the lower weight 40 can be attached with an angle suitable for attachment to the car body 21 side. On the other hand, when the upper weight 42 is mounted on the lower weight 44, the upper weight 42 can be mounted in a horizontal state suitable for mounting on the lower weight 44 side.

In the present embodiment, when the lower boom (boom) 5A of the crawler crane (construction machine) 100 is folded onto the front upper end portion (upper end portion on the side away from the car body 21) 42Q of the upper weight 42, A stepped notch 42A for preventing interference with the lower boom (boom) 5A is provided.

With this configuration, the stepped notch portion 42A is constant regardless of the width of the side frame 32 being reduced or expanded, and there is no risk of the operator getting caught on the slope unlike in the conventional case. In addition to being able to prevent interference when folding, the worker can move on the lower weight 40 in a certain environment, and the safety at the time of work can be improved.

In the present embodiment, the front upper end portion (upper end portion on the side away from the car body 21) 44H of the lower weight 44 is provided when the lower boom (boom) 5A of the crawler crane (construction machine) 100 is folded. It is configured to prevent interference with the lower boom (boom) 5A, and the upper surface 44J of the lower weight 44 is set to a position that functions as a stairway following the stepped notch portion 42A. ..

With this structure, it is possible to prevent interference when the lower boom 5A is folded, and in addition, the operator can move the entire upper surface 44J where the upper weight 42 of the lower weight 44 does not overlap. , The safety at work can be improved.

The present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the gist of the present invention, and all the technical matters included in the technical idea described in the claims are included. It is the subject of the present invention. Although the above-described embodiment shows a suitable example, those skilled in the art can realize various alternatives, modifications, variations, or improvements from the contents disclosed in the specification. These are included in the technical scope described in the appended claims.

5A Lower boom (boom)
21 Car Body 32 Side Frame 40 Lower Weight 42 Upper Weight 42A Stepped Notch 42E Side of Upper Weight 42F Upper Surface of Upper Weight 42G Hanging Lug Storage Space (Position Retracted from Upper Surface of Upper Weight)
42H1 First suspension lug (suspension member)
42H2 Second suspension lug (suspension member)
42Q Upper weight front end (upper end away from car body)
43 Side step 44 Lower weight 44E Side of upper weight 44H Upper front end of lower weight (upper end away from car body)
44J Upper surface of lower weight 48A First projection (projection)
48B Second projection (projection)
48C Third projection (projection)
48D connecting member 100 crawler crane (construction machinery)

Claims (5)

A pair of side frames provided on both sides in the width direction of the car body so that the space in the width direction can be reduced and expanded,
A lower weight arranged between the pair of side frames,
The provided includes upper weights the Lower weights are mounted on the lower weight and the lower weight, a construction machine to which the Lower weights are supported by the front Symbol carbody,
A side step in which both side surfaces in the width direction of the upper stage weight are opened when the pair of side frames is expanded to be in a use state, and when the pair of side frames is contracted, the side steps are closed to be along the side faces of the upper stage weight and set to a retracted state. construction machinery, characterized in that to obtain Bei, respectively. The construction machine according to claim 1,
The upper weight is connected to the lower weight by a connecting member,
A construction machine, wherein the connecting member is fitted into protrusions protruding from the both side surfaces of the lower stage weight and the upper stage weight, respectively, and connects the upper stage weight to the lower stage weight via the protrusions. The construction machine according to claim 1,
A first suspension member and a second suspension member arranged at a position retracted from the upper surface of the upper weight,
The first suspension member is provided at a position inclined at a preset angle when the upper weight is connected to the lower weight and attached to the car body,
The construction machine, wherein the second suspending member is provided at a horizontal position when the upper weight is attached to the lower weight. The construction machine according to claim 1,
A construction machine having a stepped notch for preventing interference with the boom of the construction machine when the boom of the construction machine is folded, is provided at an upper end of the upper weight on a side away from the car body. .. The construction machine according to claim 1 ,
A bracket for pivotally supporting the side step with respect to the upper weight,
The side step has a first hole through which a fixing pin is inserted and removed,
The bracket is
A support portion that contacts the fixing pin inserted into the first hole when the side step is in the use state to hold the side step in the use state;
A second hole that communicates with the first hole when the side step is in the stored state, receives the fixing pin inserted in the first hole, and restricts rotation of the side step to the used state. A construction machine having: