JP2010174448A - Earth removing device of construction machinery - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To increase the strength of a joint between right and left arms and a cylinder mounting beam. <P>SOLUTION: Both rightward and leftward ends of the cylinder mounting beam 27 are formed as right and left flare portions 30 and 29 which are diameter-enlarged in an oval cross-sectional shape. Thus, the length of a weld bead 31 formed on the periphery of the outer peripheral edge 29A of the left flare portion 29 can be secured in a large dimension when the outer peripheral edge 29A is circumferentially welded to a lateral surface 22C of the left arm 22; and the length of the weld bead 31 formed on the periphery of the outer peripheral edge 30A of the right flare portion 30 can be secured in a large dimension when the outer peripheral edge 30A is circumferentially welded to a lateral surface 23C of the right arm 23. Consequently, the jointing strength of the joint between the right and left arms 23 and 22 and the cylinder mounting beam 27 can be increased, and the reliability of the earth removing device 21 can be enhanced. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a soil removal device for a construction machine that is mounted on a construction machine such as a hydraulic excavator or a wheel loader and is preferably used for soil removal work such as earth and sand.

  In general, a hydraulic excavator as a construction machine has a vehicle body that includes a self-propelled lower traveling body and an upper revolving body that is rotatably mounted on the lower traveling body. A working device for excavating earth and sand is provided on the front side of the upper swing body so as to be able to move up and down, and an earth removing device for removing earth and sand is provided on the lower traveling body. Yes.

  Here, the excavator soil removal device is usually composed of a hollow cylinder extending in the front and rear directions, and a left and right arm having a proximal end rotatably attached to the lower traveling body, and the left and right arms. The left and right arms are arranged between the left and right arms, located on the rear side of the blade, extending left and right on the tip side of the arm. A cylinder mounting beam joined to each of the arms and a blade cylinder located between the left and right arms and between the vehicle body and the cylinder mounting beam. The blade can be turned up and down through the left and right arms.

  When performing earth removal work such as earth and sand, for example, the left and right arms are rotated downward and the blades are grounded by running the hydraulic excavator with the blades in contact with the ground. The earth and sand are pushed out by the blade in the running direction and discharged. Thereby, the ground of the work site can be smoothed and leveled.

JP 2004-353301 A

  By the way, at the time of earth removing work using the earth removing device, for example, when one of the left end side and the right end side of the blade rides on a rock on the ground, a load in an oblique direction from the ground to the blade is applied. In this case, stress concentrates on the joint between the left and right arms and the cylinder mounting beam.

  On the other hand, in the earth removal device according to the prior art, for example, it is necessary to increase the strength of the joint portion by performing multilayer welding on the joint portion between the left and right arms and the cylinder mounting beam. There is a problem that workability when joining the arm and the cylinder mounting beam by welding is lowered.

  In addition, since one end of the blade cylinder is connected to the left and right intermediate portions of the cylinder mounting beam via a cylinder mounting bracket, when the blade cylinder is extended or contracted, the left and right of the cylinder mounting beam A large out-of-plane load acts on the intermediate part in the direction.

  For this reason, in order to increase the rigidity of the cylinder mounting beam, when the thickness of the cylinder mounting beam made of a pipe body is increased, there is a problem that the weight of the cylinder mounting beam increases.

  In addition, when the thickness of the cylinder mounting beam is increased, the cylinder mounting beam is used to compensate for the difference (rigidity difference) between the rigidity of the cylinder mounting beam and the rigidity of the left and right arms. It is necessary to join a reinforcing plate to the inner surface of the left and right arms to be joined by means of welding or the like, and the work to join this reinforcing plate is added, so the cylinders on the left and right arms There exists a problem that workability | operativity at the time of joining a beam for attachment will fall.

  The present invention has been made in view of the above-described problems of the prior art, and can increase the strength of the joint between the left and right arms and the cylinder mounting beam, and increase the rigidity of the cylinder mounting beam. An object of the present invention is to provide a soil removal device for a construction machine that can be used.

  In order to solve the above-described problems, the present invention includes a left and right arm, which is composed of a hollow cylindrical body extending in the front and rear directions, and whose base end side is rotatably attached to the vehicle body of the construction machine. A blade for earth removal work provided extending left and right on the tip side of the arm, and both left and right ends located between the left and right arms located behind the blade Is provided between the left and right arms and between the vehicle body and the cylinder mounting beam. The present invention is applied to a soil removal device for a construction machine that includes a blade cylinder that is pivoted to the right.

  The left and right end portions of the cylinder mounting beam are formed as left and right flare portions that expand in a morning glory shape, and the left and right flare portions are In a state where the upper surface and the upper surfaces of the left and right arms are smoothly continuous and the lower surfaces of the left and right flare portions and the lower surfaces of the left and right arms are smoothly continuous, the flare portions and the The configuration is such that each arm is welded.

  According to a second aspect of the present invention, the left and right flares have an elliptical, oval or rectangular cross-sectional shape extending in the length direction of the left and right arms, and the left and right arms are The left and right flare portions are formed by a rectangular tube having a square cross-sectional shape, and the upper end portions of the left and right flare portions are welded to the upper corners of the left and right arms, respectively. The lower end of each is welded to the corners on the lower end side of the left and right arms.

  According to a third aspect of the present invention, the cylinder mounting beam is formed in a cylindrical portion that is located in an intermediate portion in the left and right directions, and the left and right portions that are formed on both left and right ends. A right flare portion is provided, and a pair of cylinder mounting brackets for mounting the blade cylinder is provided on the outer peripheral side of the cylindrical portion.

  According to a fourth aspect of the present invention, a reinforcing rib is provided on the inner peripheral side of the cylindrical portion at a position corresponding to the pair of cylinder mounting brackets.

  According to a fifth aspect of the present invention, the cylinder mounting beam is configured such that the cylindrical portion, the flare portion, and the reinforcing rib are integrally formed by casting means.

  According to the first aspect of the present invention, both left and right ends of the cylinder mounting beam are formed as flare portions having a morning glory-like diameter, and between the left and right flare portions and the left and right arms. By welding, it is possible to secure a large length of the welded portion formed around the flared portion, so that the joint strength of the joint portion between the left and right arms and the cylinder mounting beam can be increased. .

  In addition, the upper surface of each flare and the upper surface of each arm are smoothly continuous, and the lower surface of each flare and the lower surface of each arm are smoothly continuous, so that the left and right arms and the cylinder mounting beam are connected. It is possible to suppress the concentration of stress at the joint, and the joint strength of the joint can be further increased. Furthermore, since it is not necessary to perform multi-layer welding on the joint between the left and right arms and the cylinder mounting beam, it is possible to improve workability when joining the left and right arms and the cylinder mounting beam by welding. it can.

  According to the second aspect of the present invention, the left and right arms are constituted by square cylinders, and the upper ends of the left and right flare portions are formed at the upper corners of the left and right arms, which have high rigidity. Welding and welding the lower end of the left and right flares to the corner of the lower end with high rigidity can increase the joint strength of the joint between the left and right arms and the cylinder mounting beam. it can.

  According to the invention of claim 3, the cylinder mounting beam is constituted by the cylindrical portion located at the middle portion in the left and right directions and the left and right flare portions located at both the left and right direction sides. In addition, it is possible to suppress dirt and the like from adhering to the upper surface side of the cylinder mounting beam, and it is possible to simplify the cleaning operation and the like. Further, by providing a pair of cylinder mounting brackets on the outer peripheral side of the cylindrical portion, external force acting from the blade cylinder can be received by the highly rigid cylindrical portion.

  According to the invention of claim 4, by providing the reinforcing rib at a position corresponding to the cylinder mounting bracket on the inner peripheral side of the cylindrical portion, the rigidity of the cylindrical portion receiving the external force from the blade cylinder is increased, and the cylinder mounting The rigidity of the entire beam can be increased. In addition, by increasing the rigidity of the cylinder mounting beam by means of the reinforcing rib, it is not necessary to increase the thickness of the entire cylindrical cylinder mounting beam, so that the weight of the cylinder mounting beam can be reduced while ensuring the rigidity of the cylinder mounting beam. It is possible to improve workability when the cylinder mounting beam is joined to the left and right arms.

  According to the fifth aspect of the present invention, the cylindrical portion, the left and right flare portions, and the reinforcing rib constituting the cylinder mounting beam are integrally formed by the casting means, so that the cylindrical portion and the left and right flare portions are The boundary portion can be formed as a smooth continuous surface, and the rigidity of the entire cylinder mounting beam can be increased.

It is a front view which shows the hydraulic excavator provided with the earth discharging apparatus by embodiment of this invention. It is a top view which shows the lower traveling body and soil removal apparatus in FIG. It is a top view which shows a left and right arm, a blade, a cylinder mounting beam, and the like. It is a perspective view which expands and shows the junction part of the right flare part of a beam for cylinder attachment, and a right arm. It is sectional drawing which looked at the junction part of a right flare part and a right arm from the arrow VV direction in FIG. It is sectional drawing which looked at the right arm, the blade, the right flare part, etc. from the arrow VI-VI direction in FIG. It is a perspective view which shows a cylinder mounting beam alone. It is the left view which looked at the beam for cylinder attachment from the arrow VIII-VIII direction in FIG. It is sectional drawing which looked at the beam for cylinder attachment from the arrow IX-IX direction in FIG. It is sectional drawing which looked at the state which earth | grounded the braid | blade to the ground from the arrow XX direction in FIG. It is sectional drawing similar to FIG. 10 which shows the state which rotated the braid | blade to the upper limit position. It is sectional drawing similar to FIG. 10 which shows the state which rotated the braid | blade to the minimum position. It is sectional drawing similar to FIG. 6 which shows the 1st modification of a flare part. It is sectional drawing similar to FIG. 6 which shows the 2nd modification of a flare part.

  Hereinafter, the soil removal apparatus for construction machines according to the present invention will be described in detail with reference to the accompanying drawings, taking as an example the case of application to a soil removal apparatus for a hydraulic excavator.

  In the figure, reference numeral 1 denotes a hydraulic excavator as a typical example of a construction machine. A body of the hydraulic excavator 1 includes a self-propelled crawler-type lower traveling body 2 and a swiveling wheel 3 on the lower traveling body 2. The upper revolving unit 4 is mounted so as to be capable of swiveling. A swing type working device 5 is provided on the front side of the upper swing body 4 so as to be swingable leftward and rightward, and capable of being lifted up and down. For excavation work.

  Here, the lower traveling body 2 of the excavator 1 has a track frame 6 serving as a base, and as shown in FIGS. 1 and 2, the track frame 6 is a center frame located at the center in the left and right directions. 6A, the left and right side frames 6B arranged on the left and right sides of the center frame 6A and extending in the front and rear directions, and the center frame 6A and the left and right side frames 6B are connected to each other. The front and rear legs 6C and 6C are generally configured.

  Further, on the front end side of the center frame 6A that constitutes the track frame 6, a traveling body side cylinder bracket 6D that is disposed in a central portion in the left and right directions and to which a blade cylinder 34 described later is attached is sandwiched between the traveling body side cylinder bracket 6D. The left and right arm brackets 6E and 6F, which are arranged on both the left and right sides and to which the base ends of the left and right arms 22 and 23, which will be described later, are attached, are provided so as to protrude forward. A swivel wheel 3 is attached to the upper surface side of the center frame 6A.

  Further, the left and right side frames 6B constituting the track frame 6 are provided with driving wheels 7 located on one end side in the front and rear directions and idler wheels 8 located on the other end side. A crawler belt 9 is wound around the idler wheel 8.

  On the other hand, the upper swing body 4 of the excavator 1 is disposed on the left side of the swing frame 10 and the swing frame 10 as a base mounted on the track frame 6 (center frame 6A) via the swing wheel 3. Is substantially constituted by a driver seat 11 on which is seated, a counterweight 12 disposed on the rear end side of the revolving frame 10 to balance the weight with the work device 5, and a canopy 13 covering the upper side of the driver seat 11.

  Next, reference numeral 21 denotes a soil removal apparatus according to the present embodiment. This earth removing device 21 is provided on one side (for example, the front side) of the lower traveling body 2 in the front and rear directions, and for example, earth removing work for removing earth and sand excavated by using the working device 5 and snow removal. The work is performed. The earth removal device 21 includes left and right arms 22 and 23, a blade 25, a cylinder mounting beam 27, a blade cylinder 34, and the like, which will be described later.

  22 and 23 are a pair of left and right arms attached to the center frame 6A of the track frame 6. These left and right arms 22 and 23 extend forward from the center frame 6A, and the left and right tracks 9 It protrudes further forward than the front end. As shown in FIG. 3 and the like, the left and right arms 22 and 23 are integrally connected by a cylinder mounting beam 27 which will be described later. 25 is attached.

  Here, as shown in FIGS. 4 and 5, the right arm 23 is formed of a rectangular cylinder having a rectangular or rectangular cross-sectional shape surrounded by an upper surface 23A, a lower surface 23B, and left and right side surfaces 23C and 23C. ing. Further, a mounting bracket 23D is fixed to the base end side of the right arm 23 by means of welding or the like, and this mounting bracket 23D is attached to the right arm bracket 6F provided on the track frame 6 (center frame 6A). It is pin-coupled via a connecting pin 24 so as to be rotatable upward and downward (see FIG. 2).

  On the other hand, similarly to the left arm 23, the left arm 22 is also formed of a rectangular cylinder having a square or rectangular cross-sectional shape surrounded by an upper surface 22A, a lower surface 22B, and left and right side surfaces 22C and 22C. A mounting bracket 22D is fixed to the base end side of the left arm 22, and the mounting bracket 22D is rotated upward and downward via a connecting pin 24 to a left arm bracket 6E provided on the track frame 6. It is movably pinned.

  Reference numeral 25 denotes a blade (soil discharging board) provided on the front end side of the left and right arms 22 and 23, and the blade 25 is forward of the front end portions of the left and right crawler belts 9 as shown in FIG. It is arranged and extends in the left and right directions with a width dimension substantially equal to the width dimension (vehicle width) of the left and right crawler belts 9. And the blade 25 pushes the earth and sand piled up on the ground in the running direction by running the excavator 1 and discharges it.

  Here, as shown in FIGS. 3 and 6, etc., the blade 25 is formed using a plate body such as a steel plate material, and has a gentle concave curved cross-sectional shape and extends upward and downward with a front plate 25A. A rear plate 25B having an inverted L-shaped cross-section and fixed to the rear surface side of the front plate 25A, and a thick plate extending in the left and right directions, and fixed to the lower end side of the front plate 25A. A cutting edge 25C projecting obliquely downward, and a front plate 25A, a rear plate 25B, and left and right side plates 25D and 25D fixed to both left and right ends of the cutting edge 25C are roughly constituted.

  And the front-end | tip part of the left and right arms 22 and 23 is being fixed to the rear surface board 25B of the braid | blade 25 using means, such as welding. Further, a plurality of reinforcing plates 26 each having a substantially triangular shape are fixed between the rear plate 25B and the left arm 22 and between the rear plate 25B and the right arm 23, respectively.

  Reference numeral 27 denotes a cylinder mounting beam positioned between the left and right arms 22 and 23 located behind the blade 25. The cylinder mounting beam 27 is composed of a cylindrical body extending in the left and right directions, and both left and right ends are joined to intermediate portions in the length direction of the left and right arms 22 and 23, respectively. It has become. The cylinder mounting beam 27 integrally connects the left and right arms 22 and 23 and a blade cylinder 34 to be described later. Here, as shown in FIGS. 7 to 9, the cylinder mounting beam 27 extends in the left and right directions as a whole by a cylindrical portion 28, left and right flare portions 29 and 30, reinforcing ribs 32 and the like, which will be described later. The cylindrical portion 28, the left and right flare portions 29 and 30, and the reinforcing rib 32 are integrally formed using casting means.

  Reference numeral 28 denotes a cylindrical portion that constitutes an intermediate portion in the left and right directions of the cylinder mounting beam 27. The cylindrical portion 28 is a cylinder having an outer diameter smaller than the distance between the upper surface 22A and the lower surface 22B of the left arm 22, for example. It has a shape. Further, left and right flare portions 29 and 30 to be described later are provided smoothly and continuously on both left and right ends of the cylindrical portion 28, and reinforcing ribs to be described later are provided on the inner peripheral side of the cylindrical portion 28. 32 is provided. Further, a cylinder mounting bracket 33 described later is mounted on the outer peripheral side of the cylindrical portion 28.

  Reference numerals 29 and 30 denote left and right flare portions constituting both left and right ends of the cylinder mounting beam 27. These left and right flare portions 29 and 30 are located at both ends of the cylinder mounting beam 27. The diameter is expanded in a morning glory shape, and is joined to the side surfaces 22C and 23C of the left and right arms 22 and 23 using welding means.

  Here, the right flare portion 30 extends toward the right arm 23 while gradually expanding the diameter from the right end side of the cylindrical portion 28, and the outer peripheral edge portion 30A of the right flare portion 30 extends to the side surface of the right arm 23 over the entire circumference. 23C is welded. The cross-sectional shape of the right flare portion 30 is formed in an elliptical shape in which the length direction (front and rear directions) of the right arm 23 is the major axis, and the outer peripheral edge 30A of the right flare portion 30 is connected to the right arm 23. When the entire circumference is welded to the side surface 23C, the length of the weld bead 31 formed around the outer peripheral edge 30A can be ensured to be large.

  Further, as shown in FIG. 5 and the like, an upper side chamfered portion 30B1 is provided on the upper end side of the outer peripheral edge portion 30A of the right flare portion 30 so as to form a reed groove with the side surface 23C of the right arm 23. On the lower end side of the outer peripheral edge portion 30 </ b> A of the right flare portion 30, there is provided a lower side surface chamfering portion 30 </ b> C <b> 1 that forms a ledge-shaped groove with the side surface 23 </ b> C of the right arm 23.

  Then, by welding the outer peripheral edge portion 30A of the right flare portion 30 to the side surface 23C of the right arm 23 over the entire circumference, the upper end portion of the right flare portion 30 has an upper surface 23A and a side surface 23C of the right arm 23. The lower end portion of the right flare 30 is joined to the lower corner portion 23B1 where the lower surface 23B and the side surface 23C of the right arm 23 intersect.

  As a result, the upper surface 30B of the right flare part 30 smoothly continues to the upper surface 23A of the right arm 23, and the lower surface 30C of the right flare part 30 continues smoothly to the lower surface 23B of the right arm 23, so that the right flare part 30 The stress can be prevented from concentrating on the joint between the right arm 23 and the right arm 23.

  On the other hand, the left flare portion 29 extends toward the left arm 22 while gradually increasing in diameter from the left end side of the cylindrical portion 28, and the outer peripheral edge portion 29A of the left flare portion 29 extends to the side surface 22C of the left arm 22 over the entire circumference. It is welded to. Here, the cross-sectional shape of the left flare portion 29 is formed in an elliptical shape in which the length direction of the left arm 22 is the long axis, like the right flare portion 30, and the outer peripheral edge portion 29A of the left flare portion 29 is When the entire circumference is welded to the side surface 22C of the left arm 22, the length of the weld bead 31 formed around the outer peripheral edge portion 29A can be secured.

  Further, as shown in FIG. 9 and the like, an upper side chamfered portion 29B1 is provided on the upper end side of the outer peripheral edge portion 29A of the left flare portion 29 so as to form a re-shaped groove with the side surface 22C of the left arm 22. On the lower end side of the outer peripheral edge portion 29 </ b> A of the left flare portion 29, there is provided a lower side chamfer portion 29 </ b> C <b> 1 that forms a re-shaped groove with the side surface 22 </ b> C of the left arm 22.

  Then, by welding the outer peripheral edge portion 29A of the left flare portion 29 to the side surface 22C of the left arm 22 over the entire circumference, the upper end portion of the left flare portion 29 has an upper surface 22A and a side surface 22C of the left arm 22. The lower end of the left flare portion 29 is joined to the lower corner portion (not shown) where the lower surface 22B and the side surface 22C of the left arm 22 intersect with the upper corner portion 22A1 (see FIG. 3). Be joined.

  As a result, like the right flare portion 30, the upper surface 29B of the left flare portion 29 is smoothly continuous with the upper surface 22A of the left arm 22, and the lower surface 29C of the left flare portion 29 is smooth on the lower surface 22B of the left arm 22. It is the structure which can suppress that stress concentrates on the junction part of the left flare part 29 and the left arm 22 continuously.

  Reference numeral 32 denotes a reinforcing rib provided on the inner peripheral side of the cylindrical portion 28 constituting the cylinder mounting beam 27. The reinforcing rib 32 reinforces a cylindrical portion 28 that receives a load from a blade cylinder 34 described later from the inside thereof. To do. Here, the reinforcing rib 32 is provided at a position corresponding to a cylinder mounting bracket 33 to be described later on the inner peripheral side of the cylindrical portion 28, and as shown in FIG. It is formed in the shape of a flat plate extending along the radial direction of the cylindrical portion 28.

  The reinforcing rib 32 is slightly below the axial center line OO of the blade cylinder 34 when the blade cylinder 34 is contracted and the blade 25 is rotated to the upper limit position (the state shown in FIG. 11). In the state where the blade cylinder 34 is extended and the blade 25 is rotated to the lower limit position (the state shown in FIG. 12), the blade cylinder 34 is positioned slightly above the axial center line OO. It has become.

  As described above, the reinforcing rib 32 is located at a position extending in the radial direction of the cylindrical portion 28 along the axial center line OO of the blade cylinder 34 when the blade 25 is rotated between the upper limit position and the lower limit position. It arrange | positions and reinforces the cylindrical part 28 from an inner peripheral side. Thereby, when the blade 25 is rotated, an out-of-plane load acting on the cylindrical portion 28 of the cylinder mounting beam 27 from the blade cylinder 34 can be reliably received by the cylindrical portion 28 reinforced by the reinforcing rib 32. It has become.

  The cylinder mounting beam 27 according to the present embodiment is formed by integrally forming the above-described cylindrical portion 28, left and right flare portions 29, 30 and reinforcing ribs 32 using casting means. 28 and the left and right flare portions 29 and 30 can be formed as a smooth continuous surface, and the overall rigidity of the cylinder mounting beam 27 can be increased.

  Reference numeral 33 denotes a pair of left and right cylinder mounting brackets provided on the outer peripheral side of the cylindrical portion 28 constituting the cylinder mounting beam 27. The pair of cylinder mounting brackets 33 are mounted on the bottom side of a blade cylinder 34 described later. It is what Here, each cylinder mounting bracket 33 is formed, for example, as a plate having a substantially triangular shape using a steel plate material or the like, and is arranged on the outer peripheral surface of the cylindrical portion 28 in a state of facing the left and right directions with a certain interval. It is fixed integrally using welding means.

  A blade cylinder 34 is provided between the left and right arms 22 and 23 and is provided between the track frame 6 of the lower traveling body 2 and the cylinder mounting beam 27. The blade cylinder 34 includes the left and right arms. The blade 25 provided on the tip side of the arms 22 and 23 is rotated upward and downward.

  Here, the bottom side of the blade cylinder 34 is rotatably connected to the cylinder mounting bracket 33 of the cylinder mounting beam 27 via a connecting pin 35, and the rod side of the blade cylinder 34 is driven by the track frame 6. The body side cylinder bracket 6 </ b> D is rotatably connected via a connection pin 36.

  Accordingly, when the blade cylinder 34 is expanded and contracted, the blade 25 is centered on the connecting pin 24 that connects the left and right arms 22 and 23 and the left and right arm brackets 6E and 6F of the track frame 6 as shown in FIG. Is configured to rotate upward and downward between an upper limit position shown in FIG. 12 and a lower limit position shown in FIG.

  The earth excavator 21 of the hydraulic excavator 1 according to the present embodiment has the above-described configuration. The hydraulic excavator 1 is self-propelled to the work site by the lower traveling body 2 and then, for example, rotates the upper revolving body 4. While the working device 5 is moved upside down, excavation work such as earth and sand can be performed.

  On the other hand, when the earth and sand excavated and piled up on the ground is discharged, the blade 25 is moved through the left and right arms 22 and 23 by extending the blade cylinder 34, for example, as shown in FIG. By rotating downward, the cutting edge 25C of the blade 25 is grounded to the ground. By running the excavator 1 in this state, the earth and sand accumulated on the ground can be discharged so as to be pushed out in the running direction by the blade 25, and the leveling work at the work site and the earth backfilling work. Etc. can be performed.

  Here, at the time of the above earth removal work, for example, when either one of the left end side and the right end side of the blade 25 rides on a rock on the ground, a load in an oblique direction is applied to the blade 25 from the ground. As a result, stress concentrates on the joint between the left and right arms 22 and 23 and the cylinder mounting beam 27.

  On the other hand, the earth removing device 21 according to the present embodiment has an elliptical shape in which both the left and right ends of the cylinder mounting beam 27 are the major axes of the length directions of the left and right arms 22 and 23. Since the left and right flare portions 29 and 30 are enlarged in diameter with a cross-sectional shape, when the outer peripheral edge portion 29A of the left flare portion 29 is welded to the side surface 22C of the left arm 22, the outer peripheral edge portion 29A The length of the weld bead 31 formed in the periphery can be secured large, and when the outer peripheral edge 30A of the right flare part 30 is welded to the side surface 23C of the right arm 23 all around, the periphery of the outer peripheral edge 30A It is possible to ensure a large length of the weld bead 31 formed on the surface.

  As described above, the left and right flared portions 29 and 30 having a morning glory-like diameter are provided on both ends of the cylinder mounting beam 27 so that the left and right arms 22 and 23 are joined to the cylinder mounting beam 27. The joint strength of the part can be increased, and the reliability of the earth removing device 21 can be increased. In addition, for example, it is not necessary to apply multilayer welding to the joints between the left and right flare portions 29 and 30 of the cylinder mounting beam 27 and the left and right arms 22 and 23, and the left and right arms 22 and 23 and the cylinder Workability when joining the mounting beam 27 by welding can be improved.

  Further, the upper end of the left flare 29 is welded to the upper corner 22A1 where the upper surface 22A and the side 22C of the left arm 22 intersect, and the lower end of the left flare 29 is connected to the lower 22B and side 22C of the left arm 22. Is welded to the lower corner of the left flared portion 29 so that the upper surface 29B of the left flare portion 29 is smoothly continuous with the upper surface 22A of the left arm 22, and the lower surface 29C of the left flare portion 29 is Smoothly continues to the lower surface 22B. As a result, it is possible to suppress stress concentration at the joint between the left flare 29 and the left arm 22, and the joint strength at the joint between the left flare 29 and the left arm 22 can be further increased.

  Similarly, the upper end portion of the right flare portion 30 is welded to the corner portion 23A1 on the upper end side where the upper surface 23A and the side surface 23C of the right arm 23 intersect, and the lower end portion of the right flare portion 30 is connected to the right arm 23. By welding to the corner portion 23B1 on the lower end side where the lower surface 23B and the side surface 23C intersect, the upper surface 30B of the right flare portion 30 continues smoothly to the upper surface 23A of the right arm 23, and the lower surface 30C of the right flare portion 30. Is smoothly continuous with the lower surface 23B of the right arm 23. As a result, it is possible to suppress stress concentration at the joint between the right flare portion 30 and the right arm 23, and the joint strength at the joint between the right flare portion 30 and the right arm 23 can be further increased.

  Further, the left arm 22 made of a rectangular cylinder has high strength at the corners 22A1 on the upper end side and the corners on the lower end side, and the right arm 23 also has the corners 23A1 on the upper end side and the corners on the lower end side. The strength of 23B1 is high. Therefore, the upper end portion of the left flare portion 29 is welded to the corner portion 22A1 on the upper end side of the left arm 22, and the upper end portion of the right flare portion 30 is welded to the corner portion 23A1 on the upper end side of the right arm 23, By welding the lower end of the left flare 29 to the corner on the lower end of the left arm 22 and welding the lower end of the right flare 30 to the corner 23B1 on the lower end of the right arm 23, The bonding strength between the right arms 22 and 23 and the cylinder mounting beam 27 can be increased.

  Further, by providing an upper side chamfered portion 29B1 on the upper surface 29B of the left flare portion 29 and a lower side chamfered portion 29C1 on the lower surface 29C, the upper and lower chamfered portions 29B1, 29C1 and the side surface 22C of the left arm 22 are connected. Re-shaped grooves can be formed between them, and the left flare portion 29 can be reliably welded to the side surface 22C of the left arm 22. Similarly, by providing the upper side chamfered portion 30B1 on the upper surface 30B of the right flare portion 30 and the lower side chamfered portion 30C1 on the lower surface 30C, the side surfaces of the upper and lower chamfered portions 30B1 and 30C1 and the right arm 23 are provided. Re-shaped grooves can be formed between the right flared portion 30 and the side surface 23 </ b> C of the right arm 23.

  Further, the radial direction of the cylindrical portion 28 along the axial center line OO of the blade cylinder 34 is located at a position corresponding to the cylinder mounting bracket 33 on the inner peripheral side of the cylindrical portion 28 constituting the cylinder mounting beam 27. Accordingly, the rigidity of the cylindrical portion 28 that receives an external force (out-of-plane load) from the blade cylinder 34 can be increased, and the rigidity of the entire cylinder mounting beam 27 can be increased.

  In addition, by increasing the rigidity of the cylinder mounting beam 27 by the reinforcing rib 32, it is not necessary to increase the thickness of the entire cylinder mounting beam 27, and the weight of the cylinder mounting beam 27 can be reduced while securing the rigidity. be able to. As a result, the workability when the cylinder mounting beam 27 is joined to the left and right arms 22 and 23 by welding can be improved.

  Further, the cylindrical portion 28, the left and right flare portions 29 and 30, and the reinforcing rib 32 constituting the cylinder mounting beam 27 are integrally formed by using casting means, so that the cylindrical portion 28 and the left and right left and right portions are formed. A boundary portion between the flare portions 29 and 30 can be formed as a smooth continuous surface. Thereby, stress does not concentrate on the boundary part between the cylindrical part 28 and each flare part 29, 30, and the rigidity of the cylinder mounting beam 27 as a whole can be increased.

  Further, the cylinder mounting beam 27 has a hollow cylindrical shape as a whole by the cylindrical portion 28 and the left and right flare portions 29 and 30. For this reason, it is possible to suppress dirt and the like from adhering to the upper surface side of the cylinder mounting beam 27, and to simplify the cleaning operation and the like.

  In the above-described embodiment, the left and right flare portions 29 and 30 constituting the left and right both ends of the cylinder mounting beam 27 are used, and the length direction of the left and right arms 22 and 23 is the long axis. The case where it forms in the elliptical cross-sectional shape which becomes is illustrated.

  However, the present invention is not limited to this. For example, as in the first modification shown in FIG. 13, the right flare portion 30 ′ having an oval cross-sectional shape extending in the length direction of the right arm 23, It may be formed as a cylinder mounting beam 27 ′ having a left flare portion (not shown) having an elliptical cross-sectional shape similar to this.

  Further, for example, as in the second modification shown in FIG. 14, the right flare portion 30 ″ having a rectangular cross-sectional shape extending in the length direction of the right arm 23, and a rectangular cross-sectional shape similar to the right flare portion 30 ″. It may be formed as a cylinder mounting beam 27 ″ having a left flare portion (not shown).

  Further, in the above-described embodiment, the cylindrical portion 28, the left and right flare portions 29 and 30, and the reinforcing rib 32 constituting the cylinder mounting beam 27 are integrally formed using casting means, and this cylinder mounting beam is formed. A case where a cylinder mounting bracket 33 made of a different member is integrally fixed to the cylindrical portion 28 of the beam 27 by welding means is illustrated.

  However, the present invention is not limited to this. For example, the cylindrical portion 28, the left and right flare portions 29, 30, the reinforcing rib 32, and the cylinder mounting bracket 33 may be integrally formed using casting means. .

1 Excavator (construction machine)
2 Lower traveling body (car body)
4 Upper swing body (car body)
21 Earth removing device 22 Left arm 22A, 23A Upper surface 22B, 23B Lower surface 22C, 23C Side surface 22A1, 23A1, 23B1 Corner portion 23 Right arm 25 Blade 27, 27 ', 27 "Cylinder mounting beam 28 Cylindrical portion 29 Left flare portion 29B, 30B Upper surface 29C, 30C Lower surface 30, 30 ', 30 "Right flare portion 32 Reinforcement rib 33 Cylinder mounting bracket 34 Blade cylinder

Claims (5)

Left and right arms consisting of hollow cylinders extending in the front and rear directions, with the base end pivotably attached to the body of the construction machine;
A blade for earth removal work provided extending in the left and right directions on the front end side of the left and right arms;
A cylinder mounting beam located between the left and right arms located behind the blade and having left and right ends joined to the left and right arms respectively;
In a soil removal device for a construction machine, comprising a blade cylinder positioned between the left and right arms and provided between the vehicle body and the cylinder mounting beam to rotate the blade upward and downward. ,
The left and right ends of the cylinder mounting beam are formed as left and right flares that expand in a morning glory shape,
The upper surface of the left and right flare portions and the upper surface of the left and right arms are smoothly continuous, and the lower surface of the left and right flare portions and the lower surface of the left and right arms are smoothly continuous. A soil removal device for a construction machine, wherein each flare portion and each arm are welded to each other. The left and right flare portions have an elliptical shape, an elliptical shape, or a rectangular cross-sectional shape extending in the length direction of the left and right arms,
The left and right arms are constituted by square cylinders having a square cross-sectional shape,
The upper ends of the left and right flares are welded to the corners on the upper ends of the left and right arms, respectively, and the lower ends of the left and right flares are on the lower ends of the left and right arms. The soil removal apparatus for a construction machine according to claim 1, wherein the earthing device is constructed so as to be welded to each corner. The cylinder mounting beam is composed of a cylindrical part located in the middle of the left and right directions and a left and right flare part formed on both ends of the left and right directions. And
The soil removal apparatus for a construction machine according to claim 1 or 2, wherein a pair of cylinder mounting brackets for mounting the blade cylinder is provided on an outer peripheral side of the cylindrical portion.   The soil removal device for a construction machine according to claim 3, wherein a reinforcing rib is provided at a position corresponding to the pair of cylinder mounting brackets on an inner peripheral side of the cylindrical portion.   The earthing device for a construction machine according to claim 4, wherein the cylinder mounting beam is configured such that a cylindrical portion, a flare portion, and a reinforcing rib are integrally formed by casting means.

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