JP2009179216A - Cab structure of construction machinery - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cab structure of construction machinery improving strength and reducing a manufacturing cost. <P>SOLUTION: The cab structure 1 of the construction machinery is equipped with the right and left front peeler parts 3 which are provided at the front part of the cab of the construction machinery and vertically extend, a front header part 4 installed between the upper end parts of the front peeler parts 3, and a front cross member part 5 installed between the lower end parts of the front peeler parts 3. The right and left front peeler parts 3, the front header part 4, and the front cross member part 5 are integrally formed with a front pipe member 21 having a hollow shape cross section bent in a rectangular shape. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a cab structure for a construction machine having a pillar portion extending vertically, a header portion spanned over an upper end portion of the pillar portion, and a cross member portion spanned over a lower end portion.

  Conventionally, as a structure of a cab of a construction machine, for example, those shown in Patent Document 1 and FIG. 8 are known.

  As shown in FIG. 8, a pair of left and right front pillar portions 82 extending in the vertical direction are provided at the front portion of the cab 81. A front header 83 is bridged between the upper ends of the pair of front pillars 82, and a front cross member 86 is bridged between the lower ends.

  A pair of left and right rear pillar portions 84 extending vertically are provided at the rear portion of the cab 81, and a pair of left and right roof rail portions 85 extending between the rear pillar portion 84 and the front pillar portion 82 are bridged between the rear pillar portion 84 and the front pillar portion 82.

  The front pillar portion 82 has a non-circular irregular cross section, and the front pillar portion 82 is formed integrally with the roof rail portion 85. As described above, the front pillar portion 82 of a modified steel pipe is generally integrated with the roof rail portion 85 extending rearward.

  The front pillar portion 82 and the roof rail portion 85 are formed, for example, by subjecting a round pipe to roll forming or drawing to form a deformed steel pipe having a predetermined cross-sectional shape, and bending the deformed steel pipe into an L shape. Is done.

JP 2002-115268 A

  However, in the cab structure described above, the front header portion 83 is a separate member from the front pillar portion 82, and the front header portion 83 is joined to the front pillar portion 82 by arc welding. There is a problem that the strength of the joint portion between 83 and the front pillar portion 82 is weak.

  For this reason, there is a possibility that the joint portion between the front header portion 83 and the front pillar portion 82 is greatly deformed due to a load input at the time of rollover of the construction machine, and the worker's safety is not satisfied.

  In addition, stress due to vibration during traveling of the construction machine is concentrated on the welded portion (corner portion) Wu between the front header portion 83 and the front pillar portion 82 and the welded portion Wl between the front cross member portion 86 and the front pillar portion 82. In some cases, this may lead to cracks and breaks in the weld.

  As described above, in the conventional cab structure, it is necessary to reinforce the joint portion between the front header portion 83 and the front pillar portion 82. However, in the case of the conventional cab structure, a deformed steel pipe formed in advance in a predetermined cross section is used. For this reason, since the cross section cannot be changed, it is necessary to reinforce it with ribs or the like of another member, leading to an increase in the number of parts and an increase in weld locations, leading to an increase in cost.

  Accordingly, an object of the present invention is to provide a construction machine cab structure that solves the above-described problems and that improves strength and reduces manufacturing costs.

  In order to achieve the above object, the present invention provides a left and right front pillar portion provided at the front portion of a cab of a construction machine and extending vertically, and a front header portion spanned between upper end portions of the front pillar portions, In the construction machine cab structure including a front cross member portion spanned between lower ends of the front pillar portion, the left and right front pillar portions, the front header portion, and the front cross member portion are rectangular. It is formed integrally with a front pipe member having a hollow cross-section bent into the shape.

  Preferably, the front pillar portion, the front header portion, and the front cross member portion are formed by hydroforming a front pipe member bent into the rectangular shape.

  Preferably, a protrusion for fitting a front end of a roof rail portion having a hollow cross section extending forward and backward along the ceiling of the cab is formed at an upper end portion of the front pipe member.

  Preferably, a corner portion where the front pillar portion and the front header portion intersect and a corner portion where the front pillar portion and the front cross member portion intersect are each expanded by hydroforming the front pipe member. Is.

  In order to achieve the above object, the present invention provides a left and right rear pillar portion provided at a rear portion of a cab of a construction machine and extending vertically, a rear header portion spanned between upper ends of the rear pillar portions, and the rear pillar portion. In the construction machine cab structure including a rear cross member portion spanned between the lower end portions of the left and right rear pillar portions, the rear header portion, and the rear cross member portion, a hollow section having a rectangular shape. It is formed integrally with a rear pipe member.

  Preferably, the rear pillar portion, the rear header portion, and the rear cross member portion are formed by hydroforming a rear pipe member bent into the rectangular shape.

  Preferably, a protrusion for fitting a rear end of a roof rail portion having a hollow cross section extending forward and backward along the ceiling of the cab is formed at an upper end portion of the rear pipe member.

  Preferably, a corner portion where the rear pillar portion and the rear header portion intersect and a corner portion where the rear pillar portion and the rear cross member portion intersect are each expanded by hydroforming the rear pipe member. is there.

  ADVANTAGE OF THE INVENTION According to this invention, the outstanding effect that the intensity | strength of the cab of a construction machine can be improved and manufacturing cost can be reduced is exhibited.

  Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

  The construction machine cab structure of the present embodiment is applied to a cab (cabin, cab) of a construction machine such as a power shovel, for example.

  The construction machine cab structure is formed by combining a plurality of members (for example, steel pipes) having a closed cross-sectional shape (hollow cross-section) and covering the members with panels, doors, windows, and the like.

  A schematic structure of the construction machine cab structure will be described with reference to FIG. In the following description, front and rear, left and right, and top and bottom refer to directions viewed from the occupant in the cab.

  As shown in FIG. 1, the construction machine cab structure 1 includes a left and right front pillar portion 3 provided at the front portion of the cab and extending vertically, and a front header portion bridged between upper end portions of the front pillar portions 3. 4, a front cross member portion 5 spanned between the lower end portions of the front pillar portion 3, left and right rear pillar portions 6 provided at the rear portion of the cab and extending vertically, and an upper end portion of these rear pillar portions 6. The rear header portion 7 spanned, the rear cross member portion 8 (see FIG. 5) spanned between the lower end portions of the rear pillar portion 6, the upper end portion of the front pillar portion 3, and the upper end portion of the rear pillar portion 6. Left and right roof rail portions 9 spanned between the left and right sides, and left and right side member portions 10 (see FIG. 5) spanned between the lower end portion of the front pillar portion 3 and the lower end portion of the rear pillar portion 6, respectively. The Obtain.

  A front window 11 that covers the front surface of the cab is provided between the left and right front pillar portions 3, and a rear panel (not shown) that covers the rear surface is provided between the rear pillar portions 6.

  A side pillar portion 12 extending vertically is provided between the front pillar portion 3 and the rear pillar portion 6 on either the left or right side (left side in the figure). A door 13 is provided in front of the side pillar 12, and a left side panel 14 having a quarter window glass 41 is provided in the rear.

  A right side panel (not shown) is provided between the other front pillar portion 3 and the rear pillar portion 6 (right side in the figure).

  A roof panel 15 is provided between the left and right roof rail portions 9 to cover the ceiling surface of the cab.

  The construction machine cab structure 1 is attached by a cab mounting member 72 on a turning frame 71 (see FIG. 7) of the construction machine. The swivel frame 71 covers the floor of the cab.

  The construction machine cab structure 1, the upper part of the turning frame 71, the operation levers, and the like constitute a cab.

  The front side of the construction machine cab structure 1 will be described with reference to FIGS. 1 to 3.

  In the present embodiment, the left and right front pillar portions 3, the front header portion 4, and the front cross member portion 5 are integrally formed by a front pipe member 21 having a hollow cross section bent in a rectangular shape when viewed from the front-rear direction. .

  The front pipe member 21 has a vertically long rectangular shape, the long sides of the rectangle form the front pillar portion 3, the upper short side forms the front header portion 4, and the lower short side forms the front cross member portion. Make a 5.

  The front pipe member 21 is disposed such that the upper end side is inclined rearward, and the front pillar portion 3 extends upward while being inclined obliquely rearward.

  The front pipe member 21 is formed by press-bending (pre-bending) a pipe material (hereinafter referred to as a blank pipe material) such as a round pipe (steel pipe) into a rectangular shape, and joining both ends of the bent blank pipe material. The

  The bending process is performed by pressing or the like so that both end portions of the blank pipe material are abutted by rectangular side portions (straight line portions). In the illustrated example, both ends of the blank pipe material are abutted at an intermediate portion of the front cross member portion 5 and welded (the joint portion is indicated by a symbol J in FIG. 1).

  Although details will be described later, in the present embodiment, after the blank pipe material is bent, the blank pipe material (front pipe member 21) is hydroformed (hydraulic pressing) before joining both ends.

  The front pipe member 21 has cross-sectional shapes different from each other in the front pillar portion 3, the front header portion 4, and the front cross member portion 5, and according to necessary functions (attachment and strength of the front window 11 and the like) of each portion. It is formed into a shape.

  That is, the cross section of the front header portion 4 is formed in a structure that can ensure rigidity with respect to an input at the time of falling while minimizing the blind spot. Moreover, the change part of each functional cross section has a shape that avoids stress concentration.

  Specifically, as shown in FIGS. 2 and 3, the front edge of the inner peripheral surface of the front pipe member 21 (the lower surface of the front header portion 4, the inner surface of the front pillar portion 3, and the upper surface of the front cross member portion 5). Further, a frame portion 22 that protrudes inward of the cab and forms a sash of the front window 11 is formed over the entire circumference.

  In addition, a roof panel mounting step 23 is formed on the rear edge of the upper surface of the front header 4 so that the recessed roof panel 15 is fitted on the inner side (lower side) of the cab. A side panel attachment stepped portion 24 into which the recessed door 13 (or the right side panel) is fitted on the inner side of the cab is formed at the edge.

  The cross-sectional shapes of the front pillar portion 3, the front header portion 4, and the front cross member portion 5 are formed, for example, by hydroforming the above-described bent blank pipe material (front pipe member 21).

  That is, the bent blank pipe material is accommodated in a mold, and fluid pressure is applied to the blank pipe material, so that the cross sections of the front pillar portion 3, the front header portion 4, and the front cross member portion 5 are simultaneously ( Mold at once).

  The corner portion (front upper corner portion) 25 where the front pillar portion 3 and the front header portion 4 intersect, and the corner portion (front lower corner portion) 26 where the front pillar portion 3 and the front cross member portion 5 intersect, The pipe is expanded to prevent deformation, and has a larger cross-sectional area (section modulus) than the side (straight line).

  More specifically, a tube expansion portion D (see FIG. 2) protruding inward is formed on the inner surfaces of the front upper corner portion 25 and the front lower corner portion 26, and the tube expansion portion is a gusset material. Will work as.

  The expansion of the front upper corner portion 25 and the front lower corner portion 26 is performed, for example, by hydroforming of the front pipe member 21 described above.

  At the upper end portion of the front pipe member 21, a protruding portion (hereinafter referred to as a front protruding portion) 31 in which the front end of the roof rail portion 9 is fitted is formed.

  The front protruding portion 31 protrudes rearward from the rear surface of the front upper corner portion 25 and has a shape that is similar to the cross-sectional shape (the shape of the hollow portion) of the roof rail portion 9 and slightly reduced.

  The front protrusion 31 is formed by, for example, hydroforming of the front pipe member 21 described above.

  Returning to FIG. 1, the front window 11 is disposed on the front surface of the front pipe member 21.

  The front window 11 is divided into two parts in the vertical direction, and includes an upper window 32 on the upper side, a lower window 33 on the lower side, and a seal member 34 between the upper window 32 and the lower window 33.

  The upper window 32 is a flip-up type movable window that can move from the front of the cab to the inside of the ceiling. And attached to the inner surface of each.

  Here, when the construction machine cab structure 1 of the present embodiment is applied to a power shovel, the mounting surface of the rail is flush with the integrated front pipe member 21 and the roof rail portion 9 in order to make the front window 11 movable. It is preferable to determine the shape so that

  Next, the rear side of the construction machine cab structure 1 will be described with reference to FIGS.

  The rear side has a structure that is substantially the same structure as that of the front side but is reversed with respect to the front and rear.

  That is, the left and right rear pillar portions 6, the rear header portion 7, and the rear cross member portion 8 are integrally formed by a rear pipe member 35 having a hollow cross section bent into a rectangular shape.

  The rear pillar portion 6, the rear header portion 7 and the rear cross member portion 8 have different cross-sectional shapes, and the cross-sectional shapes of the respective portions are formed according to necessary functions (strength and the like).

  Specifically, as shown in FIGS. 4 and 5, the rear edge of the rear header portion 7 and the inner edge portion of the rear surface of the rear pillar portion 6 are recessed on the inner side (front side) of the cab. A rear glass attachment step portion 36 to which a not-shown member is bonded is formed.

  In addition, a quarter window glass mounting step portion 38 is formed at the front edge of the outer side surface of the rear pillar portion 6, and a recessed quarter window glass 41 is bonded to the inner side of the cab.

  The rear upper corner portion 27 where the rear pillar portion 6 and the rear header portion 7 intersect and the rear lower corner portion 28 where the rear pillar portion 6 and the rear cross member portion 8 intersect are each expanded to form an expanded portion that functions as a gusset material. At the same time, it has a larger cross-sectional area (section modulus) than the side (straight line).

  As shown in FIG. 6, a protrusion (rear protrusion) 39 for fitting the rear end of the roof rail portion 9 is formed on the front surface of the upper end portion of the rear pipe member 35. The rear projecting portion 39 projects forward from the rear upper corner portion 27 and is inserted into the rear end of the roof rail portion 9.

  As with the front pipe member 21, the rear pipe member 35 is formed by bending a blank pipe material such as a round pipe (steel pipe) into a rectangular shape, then hydroforming, and then joining both ends.

  That is, the formation of the cross-sectional shapes of the rear pillar portion 6, the rear header portion 7 and the rear cross member portion 8, the expansion of the rear upper corner portion 27 and the rear lower corner portion 28, and the formation of the rear protrusion 39 are the front side Similarly, the rear pipe member 35 is formed by hydroforming.

  Returning to FIG. 1, the roof rail portion 9 extends back and forth from the front pipe member 21 to the rear pipe member 35 along the ceiling of the cab (the left and right outer edges of the roof panel 15).

  The roof rail portion 9 is formed to have a hollow cross section, and the front end is fitted to the front protruding portion 31 of the front pipe member 21 and the rear end is fitted to the rear protruding portion 39 of the rear pipe member 35.

  The roof rail portion 9 is joined to the front pipe member 21 and the rear pipe member 35 by welding or the like, and the front projecting portion 31 and the rear projecting portion 39 serve as backings during the welding.

  Next, the operation of the construction machine cab structure 1 of the present embodiment will be described based on FIG.

  When the construction machine falls, a load due to the weight of the construction machine or the impact of the fall is applied to the construction machine cab structure 1.

  For example, when the construction machine rolls over to the left, the upper part of the left side surface of the construction machine cab structure 1 (the roof rail portion 9 and the upper corner portions 25 and 27) is grounded, and the lateral load P from the upper side of the left side surface is built. Input to the machine cab structure 1.

  The lateral load P acts to shear and deform the front pipe member 21 and the rear pipe member 35 of the construction machine cab structure 1.

  That is, the lateral load P causes the front pillar portions 3 to be inclined and the front header portion 4 to move in parallel with the front cross member portion 5 on the front pipe member 21 side, as indicated by an imaginary line F in FIG. The same operation is performed on the rear pipe member 35 side.

  Thus, the lateral load P input to the construction equipment cab structure 1 mainly works to cause deformation at the corner portions 27-29 of the front pipe member 21 and the rear pipe member 35.

  Here, in the present embodiment, the corner portions 27-29 of the construction machine cab structure 1 are continuously formed by the front pipe member 21 and the rear pipe member 35, so that the strength is increased and the construction machine cab is increased. The above-described shear deformation of the structure 1 is suppressed.

  That is, in the conventional cab structure of FIG. 8, the corner portions Wu and Wl of the cab 81 are formed by welding, so that the corner portions Wu and Wl are weaker than other portions of the cab 81. Therefore, when the construction machine falls down, the above-described deformation (refer to F in FIG. 7) is likely to occur, and when the cab 81 (corner portions Wu, Wl) is deformed, the deformation further triggers the deformation, As a result, the load (stress) is concentrated on the corner portion.

  On the other hand, in the present embodiment, the corner portions 27-29 have sufficient strength because there are no welded portions, and are unlikely to be deformed as described above when the construction machine falls, and the corner portions 27-29. Stress does not concentrate on the surface.

  In particular, in this embodiment, the corner 27-29 of the construction machine cab structure 1 is expanded to reinforce the corner 27-29, and this also suppresses deformation of the construction machine cab structure 1 during a fall. , Stress concentration is relaxed.

  As described above, according to the construction machine cab structure 1 of the present embodiment, the stress concentration applied to the corner portions 27-29 and the joint portion J at the time of falling can be relaxed, and the rigidity and strength against the load at the time of falling can be improved. .

  Furthermore, in this embodiment, by expanding the corner portion 27-29, an effect similar to that provided with the reinforcing rib in the corner portion 27-29 is produced, and this can also improve the rigidity. As a result, reinforcing ribs and the like are not necessary, the number of parts and the number of welds can be reduced, and the manufacturing cost can be reduced.

  In addition, since the strength of the corner portion 27-29 is high, fatigue damage at the corner portion 27-29 due to vibration transmitted from the ground to the construction machine cab structure 1 through the turning frame 71 when the construction machine is traveling is prevented. it can.

  In addition, since the front pipe member 21 has a small number of parts, the sum of variations in precision of each part is reduced, and the precision around the front window 11 can be improved. In particular, when the upper window 32 can be opened and closed, high precision is required for the front pipe member 21 in order to ensure the sealing performance of the gap between the upper window 32 and the front pipe member 21. In the embodiment, the sealing property of the upper window 32 can be easily ensured.

  Further, since the amount of heat input by welding is reduced by reducing the amount of welding of the front pipe member 21, the thermal distortion is reduced, and this also improves the accuracy around the front window 11.

  By using hydroform molding to form the cross-sectional shapes of the front pipe member 21 and the rear pipe member 35, compared to the case of using roll forming or pultrusion molding, the local extension is reduced, the residual stress is reduced, and the accuracy is improved. Can do.

  That is, in the conventional cab structure of FIG. 8, when the front pillar portion 82 and the roof rail portion 85 are integrally formed, the deformed steel pipe formed in a predetermined cross-sectional shape is bent into an L shape in advance. The bending process caused local extension of the deformed steel pipe, and residual stress was generated in the front pillar portion 82 and the roof rail portion 85.

  On the other hand, in the present embodiment, after bending (pre-bending) the round pipe, hydroforming is performed to form a predetermined cross-sectional shape, so that local extension due to bending is small, and residual stress is generated. It is suppressed.

  Moreover, since the front pipe member 21 and the rear pipe member 35 have continuous hollow shapes, the cross-sectional shapes of the pillar portions 3 and 6, the header portions 4 and 8, and the cross member portions 5 and 9 can be simultaneously formed by hydroforming. And the process and time required for manufacturing the cab can be reduced.

  In addition, this invention is not limited to the above-mentioned embodiment, Various modifications and application examples can be considered.

FIG. 1 is a schematic perspective view of a construction machine cab structure according to an embodiment of the present invention. FIG. 2 is a perspective view of the upper left front viewed from the inside of the cab, and shows a front pillar portion, a front header portion, and a left roof rail portion. FIG. 3 is a perspective view of the lower left front viewed from the inside of the cab, and shows a front pillar portion and a front cross member portion. FIG. 4 is a perspective view of the upper left rear from the inside of the cab, and shows a rear pillar portion and a rear header portion. FIG. 5 is a perspective view of the lower left rear when viewed from the inside of the cab, and shows a rear pillar portion, a rear cross member portion, and a left side member portion. FIG. 6 is a perspective view of the upper left rear as viewed from the inside of the cab, similar to FIG. 4, and shows only the rear pillar portion and the rear header portion. FIG. 7 is a view for explaining the action at the time of rollover of the construction machine cab structure according to the present embodiment. FIG. 8 is a schematic perspective view of a conventional construction machine cab structure.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Construction machinery cab structure 3 Front pillar part 4 Front header part 5 Front cross member part 6 Rear pillar part 7 Rear header part 8 Rear cross member part 9 Roof rail part 10 Side member part 21 Front pipe member 35 Rear pipe member

Claims (8)

A left and right front pillar provided at the front of a cab of a construction machine and extending vertically, a front header spanned between the upper ends of the front pillars, and a lower end of the front pillar. In the construction machine cab structure with the passed front cross member part,
A construction machine cab structure in which the left and right front pillar portions, the front header portion, and the front cross member portion are integrally formed of a front pipe member having a hollow cross section bent into a rectangular shape.   The construction machine cab structure according to claim 1, wherein the front pillar portion, the front header portion, and the front cross member portion are formed by hydroforming a front pipe member bent into the rectangular shape.   The construction machine cab structure according to claim 1 or 2, wherein a projecting portion for fitting a front end of a roof rail portion having a hollow cross section extending forward and backward along the ceiling of the cab is formed at an upper end portion of the front pipe member.   The corner portion where the front pillar portion and the front header portion intersect and the corner portion where the front pillar portion and the front cross member portion intersect are each expanded by hydroforming the front pipe member. The construction machine cab structure according to any one of 3 to 3. Left and right rear pillars provided at the rear of the cab of the construction machine and extending vertically, a rear header spanned between the upper ends of the rear pillars, and a rear spanned between the lower ends of the rear pillars In construction machinery cab structure with cross member part,
A construction machine cab structure in which the left and right rear pillar portions, the rear header portion, and the rear cross member portion are integrally formed by a rear pipe member having a hollow cross section bent into a rectangular shape.   The construction machine cab structure according to claim 5, wherein the rear pillar part, the rear header part, and the rear cross member part are formed by hydroforming a rear pipe member bent into the rectangular shape.   The construction machine cab structure according to claim 5 or 6, wherein a projecting portion for fitting a rear end of a roof rail portion having a hollow cross section extending forward and backward along the ceiling of the cab is formed at an upper end portion of the rear pipe member.   The corner portion where the rear pillar portion and the rear header portion intersect and the corner portion where the rear pillar portion and the rear cross member portion intersect are each expanded by hydroforming the rear pipe member. Construction machinery cab structure described in any one.

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