JP2004052250A - Self propelled revolving work vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a propelled revolving work vehicle capable of fixedly bearing and supporting a work load without bringing about enlargement of the revolving superstructure and complication of the structure. <P>SOLUTION: The work vehicle has a lower traveling body 2, an upper revolving body 3 turnably mounted on the lower traveling body 2, a revolving frame 4 provided with a working machine support 29A substantially erected at the front end, a lift arm 14 turnably connected vertically to the support 29A, a bucket 15 turnably connected vertically to the lift arm 14 and arranged so that an opening turns forward in a grounded work condition, a hydraulic cylinder 18 for an arm turnably connected to the support 29A at one side and turnably connected to the lift arm 14 at the other side, and a hydraulic cylinder 26 for the bucket turnably connected to the support 29A at one side and to the bucket 15 through a link structure 16 at the other side. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a so-called loader-type self-propelled revolving work vehicle having an upper revolving structure provided above a lower traveling structure.
[0002]
[Prior art]
A conventional example of a so-called loader-type self-propelled revolving work vehicle in which an upper revolving structure is provided above a lower traveling structure, and a front work machine including a bucket and an arm is connected to the upper revolving structure is, for example, There is one described in JP-A-49-12704.
[0003]
In this self-propelled turning work vehicle according to the prior art, an upper turning body (upper turning section) is turnably mounted on an upper part of a lower running body (traveling device), and an arm is vertically arranged on an upper front side of the upper turning body. Pivotally connected, a bucket (shovel device) is connected to this arm so as to be vertically rotatable (so that the opening faces forward in the grounding work state), and the front end is connected to the arm. The rear end of the arm hydraulic cylinder for driving the arm is connected to a substantially central portion in the front-rear direction of the upper swing body (in other words, the arm hydraulic cylinder is arranged to enter the upper swing body).
[0004]
[Problems to be solved by the invention]
However, the above-mentioned prior art has the following problems.
[0005]
That is, in the loader-type self-propelled revolving work vehicle as described above, it is normal to carry out the work of picking up the front-side charge with a bucket and transporting or putting it into a truck or the like. A large work load (reaction force) is applied to the arm. This work load is finally transmitted to the upper revolving superstructure through the rear end of the arm and the rear end of the hydraulic cylinder for the arm, and is supported by the upper revolving superstructure. Therefore, at least a portion of the upper revolving structure to which the work load is transmitted must be a strength member having sufficient strength and capable of strongly supporting and supporting the work load.
[0006]
Here, in the prior art, as described above, the rear end of the arm is connected to the upper front side of the upper swing body, while the rear end of the hydraulic cylinder for the arm is substantially at the center of the upper swing body in the front-rear direction. Connected to That is, the portion of the upper revolving structure to which the work load (reaction force) is transmitted as described above is distributed to the front side and the substantially central portion side of the upper revolving structure. For this reason, it is necessary to provide a strength member having sufficient strength in each region, or to provide one strength member covering a wide range, for example, from a front side to a substantially central portion side so as to cover both regions. As a result, an increase in the size of the upper swing body and a complicated structure are caused.
[0007]
In particular, in the case of a relatively small self-propelled turning work vehicle corresponding to a self-weight several ton class called a so-called mini excavator in the field of self-propelled turning work vehicle, there is no room in the space of the upper revolving body itself, For example, the layout of the equipment arrangement is often extremely restricted from the beginning, for example, in which a hydraulic device (control valve device, hydraulic tank, or the like) has to be disposed in the revolving frame of the upper revolving unit. In a configuration in which the arm hydraulic cylinder itself is inserted into the upper turning body as in the above-described prior art, space makes it difficult to apply this small self-propelled turning work vehicle. Alternatively, if it is applied in a forcible manner, some of the upper revolving internal devices must be arranged in a vertically stacked manner, and the height of the vehicle increases and the stability deteriorates.
[0008]
Further, as described above, the rear end of the arm is connected to the upper front side of the upper swing body (in other words, the pivot point of the arm enters the inside of the upper swing body, and the center of rotation of the upper swing body is changed. At a position substantially close to the ground), it is impossible to turn the bucket with the bucket relatively lowered to a position close to the ground contact state (for example, it interferes with the crawler of the undercarriage). For this reason, the bucket must be lifted to a certain extent (up to a level higher than the crawler) every time the vehicle is turned, which causes a problem that the working efficiency is reduced.
[0009]
SUMMARY OF THE INVENTION An object of the present invention is to provide a self-propelled turning work vehicle that can strongly support and support a work load without increasing the size of the upper turning body and complicating the structure.
[0010]
[Means for Solving the Problems]
(1) In order to achieve the above object, a self-propelled turning work vehicle according to the present invention includes a lower traveling body, an upper revolving body rotatably mounted on an upper portion of the lower traveling body, and an upper revolving body. A revolving frame provided at a lower portion and having a work machine support portion substantially upright at a front end thereof; an arm connected to the work machine support portion so as to be vertically rotatable; And a bucket arranged such that the opening faces forward in the grounding work state, one side is rotatably connected to the work machine support, and the other side is rotatably connected to the arm. Arm hydraulic cylinder, and a bucket hydraulic cylinder, one side of which is rotatably connected to the work machine support portion and the other side of which is connected to the bucket via a link mechanism.
[0011]
In the present invention, both the arm and the arm hydraulic cylinder are both connected to the working machine support at the front end of the turning frame. As a result, a large work load (reaction force) applied to the bucket or the arm at the time of work such as picking up and loading with a bucket is finally concentrated on the working machine support portion via the rear end of the arm and the hydraulic cylinder for the arm. , And are centrally supported by the working machine support portion. With such a concentrated load support structure on the front end side of the revolving frame, it is sufficient that only the work implement support portion of the upper revolving structure be a strength member that strongly bears and supports the work load, so that the front revolving body is substantially at the center of the upper revolving structure. The revolving superstructure can be made smaller and the structure can be simplified, as compared with the conventional structure in which the upper revolving structure is divided and supported by the parts.
[0012]
In addition, as described above, the concentrated load supporting structure on the front end side of the revolving frame has no effect on the equipment arrangement space in other parts of the upper revolving superstructure (for example, in the revolving frame). Therefore, unlike the above-described conventional structure, the present invention can be reliably applied to a small self-propelled turning work vehicle in which the layout of the equipment arrangement is often extremely restricted.
[0013]
In addition, since the working machine supporting portion for supporting the rotation of the arm is disposed at the front end of the turning frame as described above, unlike the above-described conventional structure, the lower portion of the bucket or arm may be in any state. Interference with the traveling body, for example, a crawler can be prevented.
[0014]
(2) In order to achieve the above object, a self-propelled turning work vehicle according to the present invention is provided with a lower traveling body and an upper part which is rotatably mounted on an upper part of the lower traveling body and has a revolving frame below the lower traveling body. A revolving superstructure, a work implement supporting portion that is erected on a front side portion of the revolving frame, and is substantially upright at a front end of the revolving frame, and a frame reinforcing portion that is continuously provided in a front-rear direction on a rear side of the working machine support portion. A main beam, an arm vertically rotatably connected to the work machine support, and an arm vertically rotatably connected to the arm so that the opening faces forward in the grounding work state. An arranged bucket, an arm hydraulic cylinder one side of which is rotatably connected to the work machine support, and the other side of which is rotatably connected to the arm, and one side of which is rotatable with the work machine support. Connected to And a bucket hydraulic cylinder connected to the bucket via a link mechanism.
[0015]
(3) In the above (1) or (2), preferably, a seat provided on the revolving frame for an operator to board is provided, and a height of an upper end portion of the working machine support portion is set to the height of the seat. Height is approximately equal to
[0016]
As described in the above (1), when the work implement support is provided substantially vertically at the front end of the revolving frame and the connecting portion of the arm is provided at the work implement support, securing and supporting the operator's forward view. From the viewpoint of stability and strength assurance, if the height of the working machine support portion is too high, the visibility is blocked and deteriorated, the stability in the support state becomes difficult to improve, or the strength is easily secured. It becomes difficult. On the other hand, considering the convenience of loading work on a truck, for example, by a bucket, if the height of the upper end of the work implement support is too low, even if the arm connection position is arranged near the upper end of the work implement support, It is difficult to ensure a sufficient input height (damping clearance) by the bucket.
[0017]
Therefore, in the present invention, the height of the upper end portion of the working machine support portion is made substantially equal to the height of the seat, thereby achieving both of the above-mentioned contradictory factors and ensuring the forward visibility of the operator, support stability, and strength. It is possible to maintain a relatively high securing height while maintaining a relatively favorable securing property.
[0018]
(4) In any one of the above (1) to (3), preferably, the rear end of the upper revolving unit is turned within the vehicle width of the lower traveling unit or within a diameter close to the vehicle width. Form as large as possible.
[0019]
In the case where at least the rear end of the upper revolving structure is formed to have a size capable of turning within the vehicle width of the lower traveling structure or within a diameter close to the vehicle width (= so-called small rearward revolving type), the upper revolving structure has Space will be further constrained. Therefore, the effect of securing the equipment arrangement space by the concentrated load supporting structure at the front end of the turning frame as described in the above (1) becomes more effective.
[0020]
(5) In any one of the above (1) to (4), and preferably, a rotation center position of a connecting portion between the arm and the working machine support portion, and one side of the arm hydraulic cylinder. The rotation center position of the connection portion with the work machine support portion is disposed so as to be on or near the common substantially vertical axis.
[0021]
This makes it possible to further strengthen the load supporting structure in the working machine support portion, and to make the working machine support portion more compact if the strength is the same.
[0022]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
[0023]
FIG. 1 is a side view showing the entire structure of the self-propelled turning work vehicle according to the present embodiment, FIG. 2 is a top view thereof, and FIG. 3 is a front view seen from the direction A in FIG.
[0024]
In FIGS. 1 to 3, the self-propelled turning work vehicle according to the present embodiment includes, for example, snow removal work in parking lots of various stores and business facilities (restaurants, convenience stores, guesthouses, pachinko parlors, ski resorts, and the like). It is suitable for compost and animal dung processing in livestock and dairy farming, light civil works for general farmers, and the like, and a lower traveling body (traveling device) 2 having left and right infinite start-up crawlers (crawlers) 1 as traveling means. An upper revolving unit 3 rotatably mounted on the upper part of the lower traveling unit 2, a revolving frame 4 provided on the upper revolving unit 3, and forming a foundation lower structure of the upper revolving unit 3, and a front end of the revolving frame (Details will be described later), a work machine (loader device) 5 rotatably mounted in the up-down direction, a cab 7 provided on the upper swing body 3 and having a seat 6, and driving on the upper swing body 3 Large except room 7 And an upper cover 8 covering the minute.
[0025]
The lower traveling body 2 has, for example, a substantially H-shaped track frame 9, a driving wheel 10 rotatably supported near the rear ends on both the left and right sides of the track frame 9, and a left wheel for driving the driving wheel 10. A right running motor 11 and rotating wheels (idlers) 12 rotatably supported near the left and right front ends of the track frame 9 and rotated by the driving force of the driving wheels 10 via the crawler belt 1. ing. A swivel bearing (slewing bearing) 13 is disposed at the center of the lower traveling body 2, and the upper revolving superstructure 3 is rotated 360 ° with respect to the lower traveling body 2 by a driving force of a hydraulic motor for rotation (not shown). It can be turned freely. At this time, as shown in FIG. 1, the upper revolving structure 3 is configured such that the rear end thereof can turn within a diameter close to the vehicle width of the lower traveling structure 2 (= a diameter slightly larger than the vehicle width). (So-called small backward turning type). Note that the loader device 5 is configured to be able to turn within a range somewhat larger than the turning radius of the upper turning body 3.
[0026]
The loader device 5 includes a pair of left and right arms (lift arms) 14 that are bent in a substantially “U” shape, a work tool (bucket) 15 rotatably coupled to the lift arms 14, This is a so-called loader-type working machine that includes a link mechanism 16 including a link body 16a and a connection bar 16b, and is arranged so that the opening of the bucket 15 faces forward in the grounding work state illustrated in FIG.
[0027]
One side (rear side) of the lift arms 14, 14 is rotatably connected to and supported by a main beam 29 (described later) of the revolving frame 4 via a pin 17. Further, the lift arm 14 includes a bracket portion (cylinder connection portion) 14a provided at a lower portion of the intermediate portion having the above-mentioned substantially "V" shape. A front end side (rod portion in this example) of the arm hydraulic cylinder 18 is rotatably connected to the bracket portion 14a via a pin 19, and a rear end side (in this example) of the arm hydraulic cylinder 18 is provided. The bottom portion) is rotatably connected to and supported by a main beam 29 (described later) of the revolving frame 4 via a pin 20. With such a structure, the lift arms 14, 14 are raised and lowered in response to the expansion and contraction driving of the corresponding arm hydraulic cylinders 18, 18.
[0028]
One side of the bucket 15 (the base side, the side opposite to the opening side) is rotatably connected to and supported by the tip of the lift arm 14 via a pin 21. The bucket 15 includes a bracket (cylinder connection) 15a near the pin 21. The front end of the connection bar 16b is rotatably connected to the bracket portion 15a via a pin 22. The rear end of the connection bar 16b is connected to the front end of the link body 16a via a pin 23. .
[0029]
At this time, the lift arm 14 also includes a bracket portion (link support portion) 14b provided on the upper portion of the intermediate portion having the above-mentioned substantially "V-shape", and a substantially central portion of the link main body 16a is pinned to the bracket portion 14b. It is rotatably supported via 24. The rear end side of the link body 16 is rotatably connected to the front end side (in this example, the rod portion 26 a) of the bucket hydraulic cylinder 26 via a pin 25, and the rear end side of the bucket hydraulic cylinder 26. The bottom portion 26 b in this example is rotatably connected to and supported by a main beam 29 (described later) of the revolving frame 4 via a pin 27. With such a structure, the angle between the bucket 15 and the lift arm 14 of the bucket 15 changes according to the expansion and contraction drive of the bucket hydraulic cylinder 26. In other words, the direction in which the opening side of the bucket 15 faces from the ground side. (See FIG. 8 described later).
[0030]
FIG. 4 is a side view showing the detailed structure of the revolving frame 4, and FIG. FIG. 6 is a front view as viewed from the direction B in FIG. 4, and FIG. 7 is a top view of the revolving frame 4.
[0031]
4 to 7, the revolving frame 4 has a structure corresponding to the revolving load of the upper revolving unit 3 and the work load (work load) of the loader device 5, and has a substantially plate-like shape provided at the lowermost portion. A base portion 28, a pair of left and right main beams 29, 29 erected in a substantially vertical direction in a front region of the base portion 28 as a strength member, and further left and right of the left and right main beams 29, 29. Left and right reinforcing members 30, 30 erected on both sides, a substantially cylindrical member 31 fixed so as to bridge between the left and right main beams 29, 29, and a forward direction from the substantially cylindrical member 31. Left and right mounting brackets 32, 32 fixed so as to protrude.
[0032]
The base portion 28 conforms to the rear shape of the upper cover 8, and the rear end portion is a substantially arc-shaped (or a shape close thereto) portion 28a.
[0033]
The main beam 29 is a strength member having a structure in which a fulcrum member for mounting the loader device and a beam for securing the turning frame strength are integrated, and is functionally substantially upright at the front end of the base portion 28 corresponding to the former. And a frame reinforcement region (frame reinforcement portion) 29B continuously provided in the front-rear direction on the rear side of the work machine support portion 29A corresponding to the latter.
[0034]
The work machine support portion 29A has a height position at the upper end thereof substantially equal to the height of a seat surface of the seat 6 described later, and an arm mounting through hole for rotatably connecting the lift arm 14. 33, and an arm cylinder mounting through hole 34 for rotatably connecting the arm hydraulic cylinder 18. The left and right reinforcing members 30 are also provided with the arm mounting through holes 34. A hole 35 and an arm cylinder mounting through hole 36 are provided. These through holes 33, 34, 35, and 36 are substantially located on (or in the vicinity of) a substantially vertical axis common to each other, and the arm cylinder mounting through holes 34, 36 are provided with the arm mounting through holes 33. , 35 substantially vertically below.
[0035]
The aforementioned pins 17 and 20 are inserted and arranged in the through holes 33 and 35 for mounting the arm and the through holes 34 and 36 for mounting the arm cylinder, whereby one side (rear side) of the lift arm 14 and the hydraulic pressure for the arm are provided. The rear end side of the cylinder 18 is rotatably connected to and supported by the work implement support portion 29A.
[0036]
In other words, both the rotation fulcrum of the lift arm 14 and the rotation fulcrum of the arm hydraulic cylinder 18 have a common longitudinal axis whose front-rear position is located forward of the center of rotation of the upper revolving unit 3. The rotation fulcrum of the arm hydraulic cylinder 18 is located substantially vertically below the rotation fulcrum of the lift arm 14.
[0037]
On the other hand, as shown in FIG. 4, the mounting bracket 32 is fixed so as to project obliquely upward from the substantially cylindrical member 31 at an angle of, for example, 45 °, so as to rotatably connect the bucket hydraulic cylinder 26. The bucket cylinder mounting through hole 37 is provided. At this time, as shown in FIG. 4, the height direction position of the bucket cylinder mounting through-hole 37 is substantially the same as the height of the above-described arm mounting through-holes 33 and 35, and the front-rear direction position is the arm position. It is located substantially forward of the mounting through holes 33 and 35 in the horizontal direction.
[0038]
The aforementioned pin 27 is inserted and arranged in the bucket cylinder mounting through hole 37, whereby the rear end side of the bucket hydraulic cylinder 26 is rotatably connected to and supported by the work machine support portion 29A.
[0039]
In other words, the rotation fulcrum of the bucket hydraulic cylinder 26 has its front-rear position in front of the center of rotation of the upper swing body 3 and substantially in front of the rotation fulcrum of the lift arm 14 in the horizontal direction, and The position in the height direction is substantially at the same height as the pivot of the lift arm 14. As a result, when viewed in the relationship between the height direction and the front-back direction position, the pivot of the bucket hydraulic cylinder 26, the pivot of the lift arm 14, and the pivot of the arm hydraulic cylinder 18 are each a right triangle ( The distance between the pivot point of the bucket hydraulic cylinder 26 and the pivot point of the arm hydraulic cylinder 18 is defined as a hypotenuse, and the distance between the pivot point of the bucket hydraulic cylinder 26 and the pivot point of the lift arm 14. , And the distance between the rotation fulcrum of the lift arm 14 and the rotation fulcrum of the arm hydraulic cylinder 18 is two sides forming a right angle).
[0040]
Reference numeral 38 denotes a front cover provided so as to connect the left and right reinforcing members 30, 30; 39, a mounting portion of the hydraulic motor for turning; 40, a mounting portion of the above-described swivel bearing 13; 41, a mounting portion of the engine. It is.
[0041]
Further, a turning frame cover 42 is provided on the outer peripheral side of the turning frame 4 having the above structure, as shown in FIG.
[0042]
Returning to FIGS. 1 to 3, the cab 7 is provided on the upper revolving unit 3 on the left side. In front of the seat 6 in the driver's cab 7, left and right running levers 43 for driving the left and right running hydraulic motors 11 of the lower running body 2, respectively, and a front for preventing the operator from falling forward. The left and right working levers 45L. For driving the stay 44 and the arm hydraulic cylinder 18 and the bucket hydraulic cylinder 26 to operate the lift arm 14 and the bucket 15, respectively. 45R are provided. At this time, the right working lever 45R can operate the scooping / dumping operation of the bucket 15 and the raising / lowering operation of the lift arm 14. The left working lever 45L can operate a turning operation. The left and right working levers 45L, 45R may be provided not only on the front side of the seat 6 but also on both left and right sides of the seat 6.
[0043]
A side stay 46 is provided on the left side of the seat 6 to prevent the operator from falling to the left side, and a roof 48 is provided above the seat 6 via a support member 47.
[0044]
Although not shown in detail, the upper cover 8 includes therein an engine, a hydraulic pump driven by the engine, a fuel tank for storing fuel of the engine, and a hydraulic oil tank serving as a hydraulic oil source for the hydraulic pump. And other equipment.
In the self-propelled revolving work vehicle of the present embodiment configured as described above, the snow removal work in the parking lots of the various stores and business facilities described above, the compost and livestock disposal work in livestock and dairy farms, and the light civil engineering work of general farmers When performing general loader work (such as scooping, transporting, unloading / discharging or loading) in a work, etc., unlike the excavation work of a hydraulic excavator that stops running and operates the front work machine, the loader device moves forward. Work by inserting 5. For this reason, during this work, a large work load (reaction force) is applied to the bucket 15 and the lift arm 14, and this work load is eventually applied to the rear end of the lift arm 14 and the rear end of the arm hydraulic cylinder 18. Is transmitted to the upper swing body 3 via the upper swing body 3 and is supported by the upper swing body 3.
[0045]
Here, in the self-propelled revolving work vehicle of the present embodiment, both the lift arm 14 and the arm hydraulic cylinder 18 are connected to the main beam working machine support portion 29A at the front end of the revolving frame 4, and in particular, The connection position (rotation fulcrum position) is close. As a result, the work load is finally intensively transmitted to the work implement support 29A via the rear end of the lift arm 14 and the arm hydraulic cylinder 18, and the work implement support 29A (in other words, the main The beam 29 is intensively supported on the front side of the beam 29). As a result of such a concentrated load supporting structure on the front end side of the revolving frame 4, a strength member that strongly supports and supports only the main beam 29 only with the main beam 29 in combination with the frame reinforcing area 29B that performs the original strength securing function of the upper revolving body 3. Is enough. Therefore, the size of the upper swing body 3 can be reduced, and the structure can be particularly simplified, as compared with the above-described conventional structure in which the upper swing body is divided and supported by the front side and the substantially central portion side.
[0046]
Further, as described above, both the rotation fulcrum of the lift arm 14 and the rotation fulcrum of the arm hydraulic cylinder 18 are located at the front and rear positions on the front side with respect to the center of rotation of the upper swing body 3 and have a common substantially It is positioned substantially on the vertical axis, and the pivot point of the arm hydraulic cylinder 18 is located substantially vertically below the pivot point of the lift arm 14. With such a configuration, the load supporting structure in the working machine support portion 29A can be made stronger, and if the strength is the same, the working machine support portion 29A can be made more compact.
[0047]
Further, by providing the concentrated load supporting structure on the front end side of the revolving frame 4 as described above, the other portion of the upper revolving superstructure 3 (for example, the upper part of the main beam frame reinforcing area 29, in other words, in the so-called revolving frame in the normal structure). It has no effect on the equipment placement space. Therefore, unlike the above-described conventional structure, the layout of the equipment arrangement can be applied to a small self-propelled turning work vehicle in which the layout of the equipment arrangement is often extremely limited. The degree of freedom can be ensured, and the driver's seat 7 space can be ensured to ensure good livability.
[0048]
In addition, in the self-propelled turning work vehicle of the present embodiment, the upper revolving unit 3 is able to make a full 360 ° turn regardless of the orientation of the lower traveling unit 2, thereby changing the position and changing the direction of the lower traveling unit 2. The direction of the bucket 15 containing the goods can be changed to itself without the need to carry out. Therefore, for example, even in the work in a narrow place, the conveyed goods scooped by the bucket 15 can be easily discharged to a position other than the scooped position (any position in all directions of 360 °) irrespective of the position and direction of the lower traveling body 2. Soil and discharge can be performed, and convenience can be greatly improved, and work efficiency can be improved.
[0049]
FIG. 8 is an explanatory diagram illustrating the operation state of the lift arm 14 and the bucket of the self-propelled turning work vehicle according to the present embodiment. The self-propelled revolving work vehicle of the present embodiment has a structure in which the work implement supporting portion 29A for rotatably supporting the lift arm 14 is provided at the front end of the revolving frame 4 as described above, and as shown in FIG. Unlike the above-described conventional structure, regardless of the position of the bucket 15 or the lift arm 14 (in other words, even when the bucket 15 is at the lowest state where the bucket 15 is in contact with the ground), it can be rotated 360 ° in any direction. Interference with the crawler belt 1 of the undercarriage 2 can be prevented.
[0050]
At this time, the main beam 29 also serves as the concentrated load support at the front end side of the revolving frame 4 and the function of securing the original strength of the revolving superstructure 3 as described above, so that the upper revolving superstructure 3 has a 360 ° angle. Even when the vehicle is turned in the direction, the strength of the turning frame 4 can be ensured and the stability of the vehicle body can be ensured. As a result, safe driving becomes possible. In particular, even when the loader work is performed by the forward plunging in a state where the front-rear direction of the lower traveling unit 2 and the front-rear direction of the upper revolving unit 3 are shifted, the durability of the revolving frame 4 is reliably prevented and local damage is prevented. it can.
[0051]
Furthermore, at this time, from the viewpoint of securing the operator's front view, supporting stability, and securing strength, if the height of the work implement support portion 29A is too high, the view is blocked and deteriorated, or the stability in the support state is deteriorated. It is difficult to improve the properties and it is difficult to easily secure the strength. On the other hand, considering the convenience at the time of loading work, for example, on a truck by the bucket 15, if the height of the upper end portion of the work implement support portion 29A is too low, the rotation of the lift arm 14 near the upper end portion of the work implement support portion 29A Even if the fulcrum is arranged, it is difficult to sufficiently secure the throwing height (damping clearance) H1 (see FIG. 8) by the bucket 15.
[0052]
Therefore, in the self-propelled turning work vehicle of the present embodiment, the height H2 (see FIG. 8) of the upper end portion of the work implement supporting portion 29A is made substantially equal to the height H3 (see FIG. 8) of the seat 6. In addition, it is necessary to ensure the operator's forward visibility, support stability, and strength assurance relatively well, and also ensure a relatively large throwing height (damping clearance) H while balancing the conflicting two. Can be.
[0053]
In particular, in the present embodiment, the loader device 5 is configured to connect the bucket 15 and the upper swing body 3 with one bent lift arm 14, so that the so-called bucket is connected and arranged via the boom and the arm. Compared with a loader type excavator, the front reach can be reduced, so that a large bucket capacity can be secured. Further, there is an effect that the above-described damping clearance H can be more easily secured by the compact loader device 5.
[0054]
Further, in the self-propelled turning work vehicle according to the present embodiment, by using the crawler track 1 as the traveling means, the contact pressure can be reduced, and the grip force and the frictional resistance can be increased. As a result, unlike the case where the wheels are used as a traveling means, the general loader work (slipping, transporting, discharging / discharging, Loading, etc.) and snow removal work. In addition, since the traveling hydraulic motor 11 is provided on each of the left and right sides, a pivot turn (pivot turn) or a spin turn is possible, and there is an effect that the turnability is good and the work efficiency can be improved particularly in a narrow place.
[0055]
In the above embodiment, the rear end of the upper revolving unit 3 is configured to be able to turn within a diameter close to the vehicle width of the lower traveling unit 2 (a diameter slightly larger than the vehicle width). However, it is not limited to this. That is, a self-propelled turning work vehicle in which the rear end of the upper revolving unit 3 turns within a diameter somewhat larger than the lower traveling unit 2, and conversely, the rear end of the upper revolving unit 3 is within the vehicle width of the lower traveling unit 2. A self-propelled turning vehicle that can turn, or a self-propelled turning vehicle that allows the loader device 5 to turn in a range slightly larger (closer to the turning radius) than the turning radius of the upper turning body 3; The present invention is also applicable to a self-propelled turning work vehicle in which all of the wheels 3 can turn within the vehicle width of the lower traveling body 2. Also in these cases, the original effects of the present invention such as downsizing of the upper swing body 3 and simplification of the structure can be obtained. However, the self-propelled turning work vehicle in which the upper turning body 3 turns with a narrower diameter has a more limited space in the upper cover 8, so the concentrated load supporting structure at the front end of the turning frame 4 described above. Thus, the effect of securing the device arrangement space is more effective.
[0056]
【The invention's effect】
According to the present invention, since the concentrated load supporting structure is provided on the front end side of the revolving frame, it is sufficient that only the work implement supporting portion of the upper revolving body is a strength member that strongly supports and supports the work load, and the front of the upper revolving body is sufficient. The revolving superstructure can be made smaller and the structure can be simplified, as compared with the conventional structure in which the upper and lower revolving bodies are supported by being distributed on the side and the substantially central part.
[Brief description of the drawings]
FIG. 1 is a side view showing the entire structure of a self-propelled turning work vehicle according to an embodiment of the present invention.
FIG. 2 is a top view showing the entire structure of the self-propelled turning work vehicle according to one embodiment of the present invention.
FIG. 3 is a front view as viewed from a direction A in FIG. 1;
FIG. 4 is a side view showing a detailed structure of the revolving frame shown in FIG.
5 is an extracted perspective view of a main part of the turning frame structure shown in FIG. 4;
FIG. 6 is a front view as viewed in the direction of arrow B in FIG. 4;
FIG. 7 is a top view of the turning frame shown in FIG. 4;
FIG. 8 is an explanatory diagram showing an operation state of a lift arm and a bucket of the self-propelled turning work vehicle shown in FIG.
[Explanation of symbols]
2 Undercarriage
3 Upper revolving superstructure
4 Swivel frame
6 seats
14 lift arm (arm)
15 buckets
16 Link mechanism
17 pin
18 Hydraulic cylinder for arm
20 pins
26 Hydraulic cylinder for bucket
27 pin
29A Work machine support
H1 Bucket input height (dumping clearance)
H2 Height of work machine support upper end
H3 Seat height

Claims (5)

An undercarriage,
An upper revolving structure rotatably mounted above the lower traveling structure,
A revolving frame provided at a lower portion of the upper revolving structure and having a work machine support portion substantially upright at a front end thereof;
An arm connected to the work machine support portion so as to be vertically rotatable,
A bucket connected to the arm so as to be rotatable in a vertical direction, and arranged such that an opening thereof faces forward in a grounding work state;
An arm hydraulic cylinder one side of which is rotatably connected to the work machine support portion and the other side of which is rotatably connected to the arm,
A self-propelled turning work vehicle, comprising: a hydraulic cylinder for a bucket connected on one side to the work machine support portion so as to be rotatable and the other side connected to the bucket via a link mechanism. An undercarriage,
An upper revolving structure that is rotatably mounted on an upper portion of the lower traveling structure and includes a revolving frame at a lower portion thereof;
A main beam comprising a working machine support portion which is erected on a front side portion of the turning frame, and which is substantially upright at a front end portion of the turning frame, and a frame reinforcing portion continuously provided in the front-rear direction on the rear side of the working machine support portion; ,
An arm connected to the work machine support portion so as to be vertically rotatable,
A bucket connected to the arm so as to be rotatable in a vertical direction, and arranged such that an opening thereof faces forward in a grounding work state;
An arm hydraulic cylinder one side of which is rotatably connected to the work machine support portion and the other side of which is rotatably connected to the arm,
A self-propelled turning work vehicle, comprising: a hydraulic cylinder for a bucket connected on one side to the work machine support portion so as to be rotatable and the other side connected to the bucket via a link mechanism. In the self-propelled revolving work vehicle according to claim 1 or 2, preferably, the vehicle has a seat provided on the revolving frame for an operator to board, and a height of an upper end portion of the work machine support portion, A self-propelled turning vehicle having a height substantially equal to the height of the seat. The self-propelled turning work vehicle according to any one of claims 1 to 3, wherein a rear end of the upper turning body can turn within a vehicle width of the lower traveling body or a diameter close to the vehicle width. A self-propelled turning work vehicle characterized by being formed in dimensions. The self-propelled turning work vehicle according to any one of claims 1 to 4, wherein a rotation center position of a connection portion between the arm and the work machine support portion, and one side of the arm hydraulic cylinder and the work. A self-propelled turning work vehicle, wherein a rotation center position of a connection portion with a machine support portion is disposed on or near a common substantially vertical axis.

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