JP6211344B2 - Excavator - Google Patents

Description

The present invention relates to an excavator having a handrail.

  For example, a construction machine such as an excavator is hand-operated so that an operator can safely move up and down when getting on and off a cab (operator's cab) or when moving up and down the upper revolving structure for maintenance of an engine or hydraulic equipment. Rails are provided.

  The handrail has a vertical pipe that is fixed to the upper swing body and extends in the vertical direction, and a horizontal pipe that extends in a horizontal direction (a direction perpendicular to the vertical pipe) with respect to the upper swing body. doing. The vertical pipe and the horizontal pipe are arranged in a lattice pattern and are joined at the intersection.

  Conventionally, in order to join the vertical pipe and the horizontal pipe at the crossing position, either the vertical pipe or the horizontal pipe (here, the horizontal pipe) is cut, and the other pipe (here, the vertical pipe is not cut). The horizontal pipe was directly butted and welded to the joining position of the

  As another joining method, a connecting pipe and a locking member are separately provided, a horizontal pipe is welded to the connecting pipe, the connecting pipe is inserted into the vertical pipe, and the connecting pipe is locked with the locking member at the crossing position. By doing so, joining a vertical pipe and a horizontal pipe in the crossing position was performed (patent document 1).

JP-A-10-102539

  However, in the method in which the vertical pipe and the horizontal pipe are directly welded at the crossing position, the welding position has a complicated shape, and there is a problem that stress concentration is likely to occur at the welding position. This problem also occurs when a horizontal pipe is welded to a connecting pipe.

  In addition, it is conceivable that the pipe diameter is increased or ribs are added at the intersections in order to alleviate stress concentration, but this configuration increases the weight.

  An exemplary object of an aspect of the present invention is to provide a construction machine having a handrail that can suppress the occurrence of stress concentration at a joint position.

According to one aspect of the invention,
A lower traveling body,
An upper swing body that is rotatably mounted on the lower traveling body;
A cab mounted on the upper swing body,
An engine room mounted at the rear of the upper swing body;
A handrail that is provided in the upper swing body and has a structure in which a vertical member extending in a vertical direction and a horizontal member extending in a horizontal direction intersect at an intersection ;
An excavator having
The handrail has a pipe joint member at the intersection,
The pipe joining member includes a first mounting portion that holds the vertical member when the vertical member is mounted, and a second mounting portion that holds the horizontal member when the horizontal member is mounted , have a, integral with the curved portion of the second mounting portion and the first mounting portion is formed at the intersection,
Welding is performed between the first mounting portion and the vertical member, and between the second mounting portion and the horizontal member, and the shape of the welded position is circular. A featured excavator .

  According to an aspect of the present invention, since it is not necessary to weld the vertical member and the horizontal member directly, the occurrence of stress concentration at the joining position between the vertical member and the horizontal member can be suppressed.

FIG. 1 is a side view showing a hydraulic excavator as an example of a construction machine according to an embodiment. FIG. 2 is a plan view schematically showing the upper swing body of the construction machine. FIG. 3 is an enlarged perspective view showing the vicinity of the handrail of the construction machine. 4A and 4B show the handrail, where FIG. 4A is a plan view, FIG. 4B is a front view, and FIG. 4C is a side view. FIG. 5 is a perspective view of the cross-shaped connecting member. FIG. 6 shows a cross-shaped connecting member, where (A) is a plan view, (B) is a front view, and (C) is a side view. FIG. 7 shows a T-shaped connecting member, (A) is a front view, (B) is a bottom view, and (C) is a side view. 8 is an enlarged cross-sectional view of the area indicated by arrow A in FIG. FIG. 9 is an enlarged cross-sectional view showing a region indicated by an arrow B in FIG. FIG. 10 is an enlarged cross-sectional view of the area indicated by arrow C in FIG.

  Reference will now be made to non-limiting exemplary embodiments of the invention with reference to the accompanying drawings.

  In the description of all attached drawings, the same or corresponding members or parts are denoted by the same or corresponding reference numerals, and redundant description is omitted. Also, the drawings are not intended to show relative ratios between members or parts unless otherwise specified. Accordingly, specific dimensions can be determined by one skilled in the art in light of the following non-limiting embodiments.

  In addition, the embodiments described below are examples rather than limiting the invention, and all features and combinations thereof described in the embodiments are not necessarily essential to the invention.

  FIG. 1 shows a construction machine according to an embodiment of the present invention. In the present embodiment, a hydraulic excavator will be described as an example of a construction machine. However, the present invention can be applied to other construction machines as long as they have handrails.

  In the construction machine, an upper swing body 2 is swingably mounted on an upper portion of the lower traveling body 1, and a cab 3 is provided on one front side of the upper swing body 2.

  A boom 4 is pivotally attached to the front center portion of the upper swing body 2 so as to be able to be raised and lowered. Further, a bucket 6 is attached to the tip of the arm 5 so as to be rotatable up and down.

  FIG. 2 is a plan view schematically showing a rear portion of the upper swing body.

  As shown in FIG. 2, an engine room 7 is formed at the rear of the upper swing body 2, and a diesel engine 8 is installed in the engine room 7. An engine hood 11 that is opened during maintenance or the like is provided on the upper part of the upper swing body 2.

  A cooling fan 8b is provided in front of the diesel engine 8, and a heat exchanger unit 13 including a radiator or the like is installed in front of the cooling fan 8b. Further, an exhaust pipe 8a is connected to the diesel engine 8, and nitrogen oxide (hereinafter referred to as NOx) in the engine exhaust gas is purified on the downstream side of the exhaust pipe 8a in order to comply with higher-order exhaust gas regulations. An exhaust gas treatment device 9 is installed.

  As the exhaust gas treatment device 9, a urea selective reduction type NOx treatment device using urea water as a liquid reducing agent is adopted. This exhaust gas treatment device 9 injects urea water upstream of a reduction catalyst (not shown) provided in the exhaust pipe 8a to reduce NOx in the exhaust gas, and promotes this reduction reaction by the reduction catalyst to reduce NOx. It is configured to detoxify.

  By the way, in the construction machine, when the operator (operator) gets in and out of the cab, or when moving up and down to the upper part of the upper swing body 2 for maintenance of the engine or hydraulic equipment, the hand can be safely moved by the operator. Rails are provided. FIG. 3 is an enlarged view of the vicinity of the position where the handrails 30 and 31 are disposed.

  As shown in the figure, a pair of left and right boom mounting support brackets 17L and 17R are erected on the front portion of the swing frame 14 of the upper swing body 2. Boom foot pins (not shown) are inserted into and removed from holes 172L and 172R formed in the support brackets 17L and 17R.

  A plurality of steps are provided on the outer side of the support bracket 17L for the operator to move up and down to the upper part of the upper swing body 2 and the like during maintenance. In the present embodiment, a configuration example in which three steps 20 to 22 are provided is shown. The first step 20 arranged at the bottom is provided on the revolving frame 14 of the upper revolving structure 2 so as to extend forward (in the direction of arrow Y1).

  Further, the second step 21 is provided on the upper part of the turning frame 14 so as to have a predetermined height. Although a space is formed in the lower part of the second step 21, the lower space of the second step 21 may be used as a tool box for storing a tool or the like, for example. In this case, the tread plate 21a of the second step 21 is configured to be openable and closable.

  The third step 22 is provided to form a step with respect to the second step 21. The height of the third step 22 is substantially equal to the height of the upper surface of the upper swing body 2. Although a space is also formed in the lower part of the third step 22, for example, a urea tank may be accommodated in the lower space of the third step 22.

  The handrails 30 and 31 are disposed in the vicinity of the first steps 20 to 22. The handrails 30 and 31 shown in FIG. 3 are used when the operator moves up and down above the upper swing body 2. However, although not shown, the handrail is provided at a position where the operator gets on and off the cab 3 or at a position where the operator or the like performs maintenance or the like on the upper swing body 2 to ensure the safety of the operator.

  Next, the handrail will be described. In the following description, the handrail 30 will be described with reference to FIGS.

  For convenience of explanation, in FIGS. 4 to 10, the arrow X1 direction in the figure is the backward direction, the arrow X2 direction in the figure is the forward direction, the arrow Y1 direction in the figure is the right direction, the arrow Y2 direction in the figure is the left direction, The arrow Z1 direction may be referred to as the upward direction and the arrow Z2 direction may be referred to as the downward direction. In addition, the arrow Y1 and Y2 directions in the figure may be referred to as the horizontal direction, and the arrow Z1 and Z2 directions in the figure may be referred to as the vertical direction.

  These directions are used for convenience of description of the handrail 30 and do not necessarily coincide with the front-rear direction and the left-right direction of the construction machine.

  FIG. 4 shows the overall structure of the handrail 30. The handrail 30 includes a first support 35, a second support 36, a first handrail pipe 40, a second handrail pipe 50, a third handrail pipe 60, a cross-shaped connecting member 70, and a T-shape. It has connecting members 80A, 80B and the like.

  In the present embodiment, a high-strength and lightweight pipe material (hollow material) is used as the metal material of the handrail portion constituting the handrail 30. However, the material of the handrail portion of the handrail 30 is not limited to this, and other materials such as a solid material can be used.

  The first support column 35 and the second support column 36 support the first handrail pipe 40, the second handrail pipe 50, and the third handrail pipe 60 that are handrails on the third step 22.

  Bases 37 and 38 are provided at the lower ends of the columns 35 and 36, respectively. When the bases 37 and 38 are bolted to the third step 22, the first and second support columns 35 and 36 are fixed in a state of being erected on the third step 22 (upper swing body 2). . In addition, in order to raise attachment strength, it is good also as a structure which provides the rib 39 in a support | pillar part like the 2nd support | pillar 36. FIG.

  The first handrail pipe 40 has an upper horizontal pipe 41 and a lower horizontal pipe 43 arranged in parallel, and a vertical pipe 42 extending in the vertical direction connecting the horizontal pipes 41, 43. . Each of the pipes 41, 42, 43 has an integral structure.

  The upper horizontal pipe 41 has a shape extending in the horizontal direction (arrow Y1, Y2 direction) and the left end extending rearward (arrow X1 direction). Therefore, as shown in FIG. 4A, the upper horizontal pipe 41 is substantially L-shaped in plan view (see FIG. 4A).

  The upper horizontal pipe 41 and the lower horizontal pipe 43 are substantially L-shaped in plan view. The horizontal length of the upper horizontal pipe 41 is shorter than the horizontal length of the vertical pipe 42 (this will be described later).

  The second handrail pipe 50 includes a horizontal pipe 51 extending in the horizontal direction and a vertical pipe 52 extending in the vertical direction, and the pipes 51 and 52 are configured integrally. The second handrail pipe 50 is substantially L-shaped when viewed from the front (see FIG. 4B).

  The third handrail pipe 60 is a straight pipe extending in the vertical direction. The third handrail pipe 60 is disposed between the horizontal pipes 41 and 51 and the lower horizontal pipe 43.

  In addition, the shape of the 1st thru | or 3rd handrail pipe 40, 50, 60 is not limited to the shape shown by this embodiment. That is, the shape of the first to third handrail pipes 40, 50, 60 can be arbitrarily set to a shape that allows the operator to safely move up and down to the upper portion of the cab 3 and the upper swing body 2 or the like. . Further, the number of handrail pipes is not limited to three as in the present embodiment, and can be appropriately selected in consideration of operator safety as described above.

  The first to third handrail pipes 40, 50, 60 are joined at predetermined positions to form a lattice shape as shown in FIG. In the present embodiment, there are three joint positions indicated by arrows A to C in FIG.

  At the joining position A, the first support column 35, the lower horizontal pipe 43, and the third handrail pipe 60 are joined using the cross-shaped connecting member 70. At the joining position B, the upper horizontal pipe 41, the horizontal pipe 51, and the third handrail pipe 60 are joined using the T-shaped connecting member 80A. Further, at the joining position C, the second support column 36, the lower horizontal pipe 43, and the vertical pipe 52 are joined using the T-shaped connecting member 80B.

  5 and 6 show the cross-shaped connecting member 70. FIG. 5 is a perspective view of the cross-shaped connecting member 70, and FIG. 6 shows a plane, a front surface, and a side surface of the cross-shaped connecting member 70, respectively.

  The cross-shaped connecting member 70 is made of metal and has a structure in which a pair of connecting member halves 71 and 72 are joined. Each of the connecting member halves 71 and 72 can be manufactured by, for example, pressing. Then, the cross-shaped connecting member 70 is formed by welding the pair of connecting member halves 71 and 72.

  Thus, the cross-shaped connecting member 70 has a structure in which half connecting member halves 71 and 72 are manufactured and joined. Therefore, the cross-shaped connecting member 70 can be easily manufactured as compared with a method in which the cross-shaped connecting member 70 is integrally formed using bulge processing or the like, and the cost of the cross-shaped connecting member 70 can be reduced.

  The cross-shaped connecting member 70 has a cross shape as a whole. The cross-shaped connecting member 70 has a vertical upper mounting portion 74 in the upper direction and a vertical lower mounting portion 75 in the lower direction. Further, it has a horizontal right mounting portion 76 in the right direction, and further has a horizontal left mounting portion 77 in the left direction.

  The vertical upper mounting portion 74 is provided with a mounting port 74a into which the lower end portion 60b of the third handrail pipe 60 is inserted. The vertical lower mounting portion 75 is provided with a mounting port 75a with which the upper end portion 35a of the first support column 35 abuts.

  Further, the horizontal right mounting portion 76 is provided with a mounting port 76a in which the lower horizontal pipe 43 is mounted. Further, the horizontal left mounting portion 77 is provided with a mounting port 77a in which the lower horizontal pipe 43 is mounted.

  Next, a structure for joining the first support column 35, the lower horizontal pipe 43, and the third handrail pipe 60 at the joining position A using the cross-shaped connecting member 70 having the above-described configuration will be described with reference to FIG. I will explain.

  As described above, in the first handrail pipe 40, the lower horizontal pipe 43 is set longer than the upper horizontal pipe 41. Specifically, the length of the upper horizontal pipe 41 is such that the right end portion 41a of the upper horizontal pipe 41 is located at the joining position B in a state where the first handrail pipe 40 is attached to a predetermined mounting position. On the other hand, the right end 43a of the lower horizontal pipe 43 is configured to be located at the joining position C in the shooting state.

  As shown in FIG. 4B, the joining position A is a midway position of the lower horizontal pipe 43. Therefore, the lower horizontal pipe 43 is configured to penetrate through the cross-shaped connecting member 70. Specifically, as shown in FIG. 8, the lower horizontal pipe 43 is horizontally oriented from the horizontal left mounting portion 77 (mounting port 77a) of the cross-shaped connecting member 70 to the horizontal right mounting portion 76 (mounting port 76a). It is the structure which penetrated to.

  As described above, the lower horizontal pipe 43 is mounted so as to penetrate through the cross-shaped connecting member 70, whereby the lower horizontal pipe 43 is held by the mounting portions 76 and 77 of the cross-shaped connecting member 70.

  Further, the lower end portion 60 a of the third handrail pipe 60 is inserted into the cross-shaped connecting member 70 from the mounting opening 74 a of the vertical upper mounting portion 74. As described above, the lower horizontal pipe 43 penetrates in the cross-shaped connecting member 70 in the horizontal direction (arrow Y1, Y2 direction).

  Therefore, when the third handrail pipe 60 is inserted into the vertical upper mounting portion 74 from the mounting port 74 a, the lower end portion 60 a of the third handrail pipe 60 comes into contact with the lower horizontal pipe 43. In this way, the lower end portion 60a contacts the lower horizontal pipe 43, whereby the third handrail pipe 60 is positioned downward. Further, in this positioned state, the third handrail pipe 60 is held by the vertical upper mounting portion 74.

  On the other hand, the upper end portion 35 a of the first support column 35 is in contact with the lower end surface 75 b of the vertical lower mounting portion 75 so as to be associated with each other.

  As described above, when the lower horizontal pipe 43, the third handrail pipe 60, and the first support column 35 are attached to the cross-shaped connecting member 70, each pie 43, 60 and the cross-shaped connecting member 70 are And between the column 35 and the cross-shaped connecting member 70 are welded and joined (specific welding positions are indicated by WE1 to WE4 in FIG. 8).

At the welding position WE1, welding is performed between the outer peripheral position of the end of the horizontal right mounting portion 76, the lower horizontal pipe 43, and the outer peripheral surface. Further, at the welding position WE2, welding is performed between the outer peripheral position of the end of the horizontal left mounting portion 77 and the outer peripheral surface of the lower horizontal pipe 43. Also, at the welding position WE3, the outer periphery of the end of the vertical upper mounting portion 74 is performed. Welding is performed between the position and the third handrail pipe 60. Further, at the welding position WE4, welding is performed at the outer peripheral position where the vertically lower mounting portion 75 and the end portion 35a of the first support column 35 are brought into contact with each other.

  Here, each of the welding positions WE1 to WE4 has a circular shape, and fillet welding or butt welding is performed at each of the welding positions WE1 to WE4. Therefore, unlike the conventional complicated welding, the welding operation can be easily performed.

  In the present embodiment, the first support column 35, the lower horizontal pipe 43, and the third handrail pipe 60 are not directly welded but are joined via the cross-shaped connecting members 70 at the respective welding positions WE1 to WE4. It is configured. For this reason, the welding shape in each welding position WE1-WE4 can be made into smooth shapes, such as a circle, and it can suppress that stress concentration generate | occur | produces.

  Further, by suppressing the stress concentration, reinforcement is provided at the welding positions WE1 to WE4, and the diameters of the first support column 35, the lower horizontal pipe 43, and the third handrail pipe 60 are increased to increase the strength. There is no need to go or Thereby, weight reduction can be achieved, raising the intensity | strength of the handrail 30. FIG.

  Further, the cross-shaped connecting member 70 has a curved portion 78 at a position where the mounting portions 74 to 77 intersect. Therefore, even if an external force is applied to the mounting portions 74 to 77 via the first support column 35, the lower horizontal pipe 43, and the third handrail pipe 60, the mounting portions 74 to 77 intersect by the bending portion 78. It is possible to prevent stress from being concentrated on the position.

  Next, the T-shaped connecting members 80A and 80B disposed at the joining positions B and C will be described. The T-shaped connecting member 80A and the T-shaped connecting member 80B have the same configuration, and only the mounting directions at the joining positions B and C are different. Therefore, the description of the T-shaped connecting members 80A and 80B is performed collectively.

  FIG. 7 shows T-shaped connecting members 80A and 80B. The T-shaped connecting members 80A and 80B are made of metal. The T-shaped connecting members 80A and 80B can be manufactured by, for example, manufacturing the connecting member halves 85 and 86 using press working or the like in the same manner as the above-described cross-shaped connecting member 70 and welding them. .

  The T-shaped connecting members 80A and 80B have a horizontal right mounting portion 81 in the right direction, a horizontal left mounting portion 82 in the left direction, and a vertical lower mounting portion 83 in the lower direction. . The horizontal right mounting portion 81 is provided with a mounting port 81a, the horizontal left mounting portion 82 is provided with a mounting port 82a, and the vertical lower mounting portion 83 is provided with a mounting port 83a.

  A horizontal pipe 51 and a vertical pipe 52 are inserted into the mounting opening 81a. Further, the upper horizontal pipe 41 and the vertical pipe 52 are inserted into the mounting opening 82a. Furthermore, the lower horizontal pipe 43 and the third handrail pipe 60 are configured to be inserted into the mounting port 83a.

  Next, the upper horizontal pipe 41, the horizontal pipe 51, the third handrail pipe 60, and the second column 36 are joined at the joining positions B and C using the T-shaped connecting members 80A and 80B having the above-described configuration. A structure to be joined will be described.

  First, a structure for joining the upper horizontal pipe 41, the horizontal pipe 51, and the third handrail pipe 60 at the joining position B using the T-shaped connecting member 80A will be described with reference to FIG.

  The end 51 a of the horizontal pipe 51 is mounted in the mounting port 81 a of the horizontal right mounting unit 81. Thereby, the horizontal pipe 51 is held by the horizontal right mounting portion 81 of the T-shaped connecting member 80A.

  The end portion 41 a of the upper horizontal pipe 41 is mounted in the mounting port 82 a of the horizontal left mounting portion 82. Thereby, the upper horizontal pipe 41 is held by the horizontal left mounting portion 82 of the T-shaped connecting member 80A.

  Furthermore, the upper end portion 60 b of the third handrail pipe 60 is mounted in the mounting port 83 a of the vertical lower mounting portion 83. As a result, the third handrail pipe 60 is held by the vertically downward mounting portion 83 of the T-shaped connecting member 80A.

  The upper horizontal pipe 41 and the horizontal pipe 51 are linear when attached to the T-shaped connecting member 80A and extend in the horizontal direction. Further, in the T-shaped connecting member 80A, the end portion 41a of the upper horizontal pipe 41 and the end portion 51a of the horizontal pipe 51 are configured to face each other. Furthermore, each end 41a, 51a is configured to face the mounting opening 83a of the vertical lower mounting portion 83.

  On the other hand, the end portion 60a of the third handrail pipe 60 is inserted into the T-shaped connecting member 80A from the mounting opening 83a of the vertical lower mounting portion 83, whereby the third handrail pipe 60 is inserted into the vertical lower mounting portion. 83. At this time, the third handrail pipe 60 is inserted to a position where the end portion 60 a contacts the upper horizontal pipe 41 and the end portions 41 a and 51 a of the horizontal pipe 51.

  As described above, the upper end portion 60b of the third handrail pipe 60 comes into contact with the end portions 41a and 51a of the upper horizontal pipe 41 and the horizontal pipe 51, thereby positioning the third handrail pipe 60 in the upward direction. Done. As described above, the lower end portion 60a of the third handrail pipe 60 is positioned by contacting the lower horizontal pipe 43 in the cross-shaped connecting member 70 (joining position A).

  Therefore, the third handrail pipe 60 has a lower end 60a abutting on the lower horizontal pipe 43 in the cross-shaped connecting member 70, and an upper end 60b in the T-shaped connecting member 80A and the upper horizontal pipe 41 and Positioning in the vertical direction is performed by contacting the horizontal pipe 51.

  As described above, when the upper horizontal pipe 41, the horizontal pipe 51, and the third handrail pipe 60 are attached to the T-shaped connecting member 80A, the pipes 41, 51, 60 and the T-shaped connecting member are connected. 80A is joined by welding (specific welding positions are indicated by WE5 to WE7 in FIG. 9).

At the welding position WE5, welding is performed between the outer peripheral position of the end portion of the horizontal right mounting portion 81 and the outer peripheral surface of the horizontal pipe 51. Further, at the welding position WE6, welding is performed between the outer peripheral position of the end of the horizontal left mounting portion 82 and the outer peripheral surface of the upper horizontal pipe 41. Further, at the welding position WE7, welding is performed between the outer peripheral position of the end portion of the vertical lower mounting portion 83 and the outer peripheral surface of the third handrail pipe 60. Next, referring to FIG. A structure in which the pipe 43, the vertical pipe 52, and the second support column 36 are joined using the T-shaped connecting member 80B will be described.

  The end 52a of the vertical pipe 52 is mounted in the mounting opening 82a of the horizontal left mounting portion 82 of the T-shaped connecting member 80B. At this time, the vertical pipe 52 is inserted through the T-shaped connecting member 80A in the vertical direction (arrow Z1, Z2 direction). Therefore, in a state where the vertical pipe 52 is mounted on the T-shaped connecting member 80B, the end 52a of the vertical pipe 52 has a predetermined amount downward from the mounting port 81a of the horizontal right mounting portion 81 (the arrow ΔL in FIG. 10). It has a configuration that protrudes only.

  The end 43 a of the lower horizontal pipe 43 is mounted in the mounting port 83 a of the vertical lower mounting portion 83. Thereby, the lower horizontal pipe 43 is held by the vertical lower mounting portion 83 of the T-shaped connecting member 80B.

  As described above, the vertical pipe 52 is disposed so as to penetrate the horizontal left mounting portions 81 and 82 in the T-shaped connecting member 80B. Therefore, when the lower horizontal pipe 43 is inserted into the vertical lower mounting portion 83, the end portion 43 a of the lower horizontal pipe 43 comes into contact with the vertical pipe 52. Thus, the end 43a of the lower horizontal pipe 43 abuts on the vertical pipe 52, whereby the lower horizontal pipe 43 is positioned in the horizontal direction.

  The end portion 36a of the second support column 36 is inserted into a portion (end portion 52a) protruding downward from the horizontal right mounting portion 81 of the vertical pipe 52 described above. The shape of the end portion 36 a of the second support column 36 is set to be equal to the shape of the lower end portion of the bending portion 84. Therefore, when the end portion 36 a of the second support column 36 is inserted into the end portion 52 a of the vertical pipe 52, the upper end portion thereof is brought into contact with the lower end portion of the horizontal right mounting portion 81. Thereby, positioning with respect to the vertical direction of the T-shaped connecting member 80 </ b> B is performed with respect to the second support column 36.

  As described above, when the second support column 36, the lower horizontal pipe 43, and the vertical pipe 52 are attached to the T-shaped connection member 80B, the support column 36 and the pipes 43, 52 and the T-shaped connection member 80B. Are joined by welding (specific welding positions are indicated by WE8 to WE10 in FIG. 10).

At the welding position WE8, welding is performed between the outer peripheral position of the end of the horizontal left mounting portion 82 and the outer peripheral surface of the vertical pipe 52. Further, at the welding position WE <b> 9, welding is performed between the outer peripheral position of the end portion of the vertical lower mounting portion 83 and the outer peripheral surface of the lower horizontal pipe 43. Further, at the welding position WE10, welding is performed at the outer periphery of the abutting position between the horizontal right mounting portion 81 and the end portion 36a of the second support column 36. Here, the T-shaped connecting member 80A, Paying attention to the welding positions WE5 to WE10 where 80B, the pipes 41, 43, 51, 52 and the second support column 36 are welded, the shapes of the welding positions WE5 to WE10 at the joining positions B and C are all circular. Therefore, fillet welding or butt welding can be used for welding at each of the welding positions WE5 to WE10. Therefore, it is not necessary to use a complicated welding method as in the prior art at the joining positions B and C, and the welding work can be simplified.

  Further, at the joining positions B and C, the pipes 41, 43, 51, 52 and the second support column 36 are joined not by direct welding but by welding to the T-shaped connecting members 80A and 80B. For this reason, the welding shape in each welding position WE5-WE10 can be made into smooth shapes, such as a circle | round | yen, and it can suppress that stress concentration generate | occur | produces.

  Further, by suppressing the stress concentration, it is not necessary to increase the strength by providing reinforcement or increasing the pipe diameter at the welding positions WE5 to WE10, and to reduce the weight while increasing the strength of the handrail 30. Can do.

  Further, in the T-shaped connecting members 80A and 80B, similarly to the cross-shaped connecting member 70, a curved portion 84 is formed at a position where the mounting portions 81 to 83 intersect with each other, and the mounting portions 74 to 77 intersect with each other. It prevents the stress from concentrating.

  The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the specific embodiments described above, and various modifications are possible within the scope of the gist of the present invention described in the claims. It can be modified and changed.

  For example, in the above-described embodiment, the lower horizontal pipe 43 is disposed so as to penetrate the cross-shaped connecting member 70 in the horizontal direction (arrow Y1, Y2 direction) at the joining position A, and the third handrail pipe 60 is connected to the lower portion. The example in which the vertical positioning is performed by contacting the horizontal pipe 43 is shown. However, the pipe extending in the vertical direction is disposed so as to pass through the cross-shaped connecting member 70, and the pipe extending in the horizontal direction contacts the pipe extending in the vertical direction in the cross-shaped connecting member 70. Therefore, the horizontal positioning may be performed.

  In the above-described embodiment, the handrail 30 has been described as an example. However, the T-shaped connecting members 80 </ b> A and 80 </ b> B can be applied to the handrail 31. Further, the cross-shaped connecting member 70 and the T-shaped connecting members 80A and 80B can be applied to handrails having various shapes having portions where a horizontal pipe and a vertical pipe intersect.

DESCRIPTION OF SYMBOLS 1 Lower traveling body 2 Upper turning body 4 Boom 5 Arm 6 Bucket 7 Engine room 8 Diesel engine 9 Exhaust gas treatment device 13 Heat exchange unit 14 Turning frame 20 1st step 21 2nd step 22 3rd step 30, 31 Handrail 35 1st First support 36 Second support 40 First hand rail pipe 41 Upper horizontal pipe 42 Vertical pipe 43 Lower horizontal pipe 50 Second hand rail pipe 51 Horizontal pipe 52 Vertical pipe 60 Third hand rail pipe 70 Cross-shaped connecting member 71 Connecting member half 72 Connecting member half 74 Vertical upper mounting portion 75 Vertical lower mounting portion 76 Horizontal right mounting portion 77 Horizontal left mounting portions 78, 84 Curved portion 80A T-shaped connecting member 80B T-shaped connecting member 81 Horizontal right mounting part 82 Horizontal left mounting part 83 Vertical downward mounting part

Claims (3)

A lower traveling body,
An upper swing body that is rotatably mounted on the lower traveling body;
A cab mounted on the upper swing body,
An engine room mounted at the rear of the upper swing body;
A handrail that is provided in the upper swing body and has a structure in which a vertical member extending in a vertical direction and a horizontal member extending in a horizontal direction intersect at an intersection ;
An excavator having
The handrail has a pipe joint member at the intersection,
The pipe joining member includes a first mounting portion that holds the vertical member when the vertical member is mounted, and a second mounting portion that holds the horizontal member when the horizontal member is mounted , have a, integral with the curved portion of the second mounting portion and the first mounting portion is formed at the intersection,
Welding is performed between the first mounting portion and the vertical member, and between the second mounting portion and the horizontal member, and the shape of the welded position is circular. A featured excavator . The shovel according to claim 1, wherein either one of the vertical member and the horizontal member passes through the pipe joining member. 2. The pipe member according to claim 1, wherein the other of the vertical member and the horizontal member is positioned by coming into contact with either the vertical member or the horizontal member. Item 2. The excavator according to Item 2.

Images